Call built-in blkid conditionaly (udev version >= 176), call standard blkid

with full path otherwise.

COPYING

@@ -0,0 +1,340 @@
+		    GNU GENERAL PUBLIC LICENSE
+		       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+     59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+			    Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Library General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have.  You must make sure that they, too, receive or can get the
+source code.  And you must show them these terms so they know their
+rights.
+
+  We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+  Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software.  If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, so
+that any problems introduced by others will not reflect on the original
+authors' reputations.
+
+  Finally, any free program is threatened constantly by software
+patents.  We wish to avoid the danger that redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary.  To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+		    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
+that is to say, a work containing the Program or a portion of it,
+either verbatim or with modifications and/or translated into another
+language.  (Hereinafter, translation is included without limitation in
+the term "modification".)  Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+  1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
+and give any other recipients of the Program a copy of this License
+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+  2. You may modify your copy or copies of the Program or any portion
+of it, thus forming a work based on the Program, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+    a) You must cause the modified files to carry prominent notices
+    stating that you changed the files and the date of any change.
+
+    b) You must cause any work that you distribute or publish, that in
+    whole or in part contains or is derived from the Program or any
+    part thereof, to be licensed as a whole at no charge to all third
+    parties under the terms of this License.
+
+    c) If the modified program normally reads commands interactively
+    when run, you must cause it, when started running for such
+    interactive use in the most ordinary way, to print or display an
+    announcement including an appropriate copyright notice and a
+    notice that there is no warranty (or else, saying that you provide
+    a warranty) and that users may redistribute the program under
+    these conditions, and telling the user how to view a copy of this
+    License.  (Exception: if the Program itself is interactive but
+    does not normally print such an announcement, your work based on
+    the Program is not required to print an announcement.)
+
+These requirements apply to the modified work as a whole.  If
+identifiable sections of that work are not derived from the Program,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works.  But when you
+distribute the same sections as part of a whole which is a work based
+on the Program, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program
+with the Program (or with a work based on the Program) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+  3. You may copy and distribute the Program (or a work based on it,
+under Section 2) in object code or executable form under the terms of
+Sections 1 and 2 above provided that you also do one of the following:
+
+    a) Accompany it with the complete corresponding machine-readable
+    source code, which must be distributed under the terms of Sections
+    1 and 2 above on a medium customarily used for software interchange; or,
+
+    b) Accompany it with a written offer, valid for at least three
+    years, to give any third party, for a charge no more than your
+    cost of physically performing source distribution, a complete
+    machine-readable copy of the corresponding source code, to be
+    distributed under the terms of Sections 1 and 2 above on a medium
+    customarily used for software interchange; or,
+
+    c) Accompany it with the information you received as to the offer
+    to distribute corresponding source code.  (This alternative is
+    allowed only for noncommercial distribution and only if you
+    received the program in object code or executable form with such
+    an offer, in accord with Subsection b above.)
+
+The source code for a work means the preferred form of the work for
+making modifications to it.  For an executable work, complete source
+code means all the source code for all modules it contains, plus any
+associated interface definition files, plus the scripts used to
+control compilation and installation of the executable.  However, as a
+special exception, the source code distributed need not include
+anything that is normally distributed (in either source or binary
+form) with the major components (compiler, kernel, and so on) of the
+operating system on which the executable runs, unless that component
+itself accompanies the executable.
+
+If distribution of executable or object code is made by offering
+access to copy from a designated place, then offering equivalent
+access to copy the source code from the same place counts as
+distribution of the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+  4. You may not copy, modify, sublicense, or distribute the Program
+except as expressly provided under this License.  Any attempt
+otherwise to copy, modify, sublicense or distribute the Program is
+void, and will automatically terminate your rights under this License.
+However, parties who have received copies, or rights, from you under
+this License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+  5. You are not required to accept this License, since you have not
+signed it.  However, nothing else grants you permission to modify or
+distribute the Program or its derivative works.  These actions are
+prohibited by law if you do not accept this License.  Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+  6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program subject to
+these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties to
+this License.
+
+  7. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Program at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Program by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
+apply and the section as a whole is intended to apply in other
+circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system, which is
+implemented by public license practices.  Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+  10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
+to ask for permission.  For software which is copyrighted by the Free
+Software Foundation, write to the Free Software Foundation; we sometimes
+make exceptions for this.  Our decision will be guided by the two goals
+of preserving the free status of all derivatives of our free software and
+of promoting the sharing and reuse of software generally.
+
+			    NO WARRANTY
+
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+		     END OF TERMS AND CONDITIONS
+
+	    How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) year  name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.

COPYING.LIB

@@ -0,0 +1,504 @@
+		  GNU LESSER GENERAL PUBLIC LICENSE
+		       Version 2.1, February 1999
+
+ Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+ 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+[This is the first released version of the Lesser GPL.  It also counts
+ as the successor of the GNU Library Public License, version 2, hence
+ the version number 2.1.]
+
+			    Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+Licenses are intended to guarantee your freedom to share and change
+free software--to make sure the software is free for all its users.
+
+  This license, the Lesser General Public License, applies to some
+specially designated software packages--typically libraries--of the
+Free Software Foundation and other authors who decide to use it.  You
+can use it too, but we suggest you first think carefully about whether
+this license or the ordinary General Public License is the better
+strategy to use in any particular case, based on the explanations below.
+
+  When we speak of free software, we are referring to freedom of use,
+not price.  Our General Public Licenses are designed to make sure that
+you have the freedom to distribute copies of free software (and charge
+for this service if you wish); that you receive source code or can get
+it if you want it; that you can change the software and use pieces of
+it in new free programs; and that you are informed that you can do
+these things.
+
+  To protect your rights, we need to make restrictions that forbid
+distributors to deny you these rights or to ask you to surrender these
+rights.  These restrictions translate to certain responsibilities for
+you if you distribute copies of the library or if you modify it.
+
+  For example, if you distribute copies of the library, whether gratis
+or for a fee, you must give the recipients all the rights that we gave
+you.  You must make sure that they, too, receive or can get the source
+code.  If you link other code with the library, you must provide
+complete object files to the recipients, so that they can relink them
+with the library after making changes to the library and recompiling
+it.  And you must show them these terms so they know their rights.
+
+  We protect your rights with a two-step method: (1) we copyright the
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+
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+modified by someone else and passed on, the recipients should know
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+author's reputation will not be affected by problems that might be
+introduced by others.
+
+  Finally, software patents pose a constant threat to the existence of
+any free program.  We wish to make sure that a company cannot
+effectively restrict the users of a free program by obtaining a
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+  Most GNU software, including some libraries, is covered by the
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+General Public License, applies to certain designated libraries, and
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+
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+
+  We call this license the "Lesser" General Public License because it
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+Public License.  It also provides other free software developers Less
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+
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+
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+
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+former contains code derived from the library, whereas the latter must
+be combined with the library in order to run.
+
+		  GNU LESSER GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
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+  
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+
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+
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+  This option is useful when you wish to copy part of the code of
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+
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+
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+
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+
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+
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+possible use to the public, we recommend making it free software that
+everyone can redistribute and change.  You can do so by permitting
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+
+  To apply these terms, attach the following notices to the library.  It is
+safest to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least the
+"copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the library's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+Also add information on how to contact you by electronic and paper mail.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the library, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the
+  library `Frob' (a library for tweaking knobs) written by James Random Hacker.
+
+  <signature of Ty Coon>, 1 April 1990
+  Ty Coon, President of Vice
+
+That's all there is to it!
+
+

INSTALL

@@ -0,0 +1,31 @@
+Installation
+============
+
+1) Generate custom makefiles.
+
+   Run the 'configure' script from the top directory.
+
+   If you don't want to include the LVM1 backwards-compatibility code use:
+     ./configure --with-lvm1=none 
+
+   To separate the LVM1 support into a shared library loaded by lvm.conf use:
+     ./configure --with-lvm1=shared
+
+   Use ./configure --help to see other options.
+
+2) Build and install.
+
+   Run 'make' from the top directory to build everything you configured.
+   Run 'make install' to build and install everything you configured.
+
+   If you only want the device-mapper libraries and tools use
+   'make device-mapper' or 'make install_device-mapper'.
+
+3) If using LVM2, create a configuration file.
+
+   The tools will work fine without a configuration file being
+   present, but you ought to review the example file in doc/example.conf.
+
+Please also refer to the WHATS_NEW file and the manual pages for the 
+individual commands.
+

Makefile.in

@@ -0,0 +1,162 @@
+#
+# Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
+# Copyright (C) 2004-2010 Red Hat, Inc. All rights reserved.
+#
+# This file is part of LVM2.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU General Public License v.2.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+SUBDIRS = doc include man scripts
+
+ifeq ("@UDEV_RULES@", "yes")
+  SUBDIRS += udev
+endif
+
+ifeq ("@INTL@", "yes")
+  SUBDIRS += po
+endif
+
+SUBDIRS += lib tools daemons libdm
+
+ifeq ("@APPLIB@", "yes")
+  SUBDIRS += liblvm
+endif
+
+# FIXME Should use intermediate Makefiles here!
+ifeq ($(MAKECMDGOALS),distclean)
+  SUBDIRS = doc include man scripts \
+    lib tools daemons libdm \
+    udev po liblvm test \
+    unit-tests/datastruct unit-tests/mm unit-tests/regex
+endif
+DISTCLEAN_DIRS += lcov_reports*
+DISTCLEAN_TARGETS += config.cache config.log config.status make.tmpl
+
+include make.tmpl
+
+libdm: include
+lib: libdm
+liblvm: lib
+daemons: lib tools
+tools: lib device-mapper
+po: tools daemons
+
+lib.device-mapper: include.device-mapper
+libdm.device-mapper: include.device-mapper
+liblvm.device-mapper: include.device-mapper
+daemons.device-mapper: libdm.device-mapper
+tools.device-mapper: libdm.device-mapper
+device-mapper: tools.device-mapper daemons.device-mapper man.device-mapper
+
+ifeq ("@INTL@", "yes")
+lib.pofile: include.pofile
+tools.pofile: lib.pofile
+daemons.pofile: lib.pofile
+po.pofile: tools.pofile daemons.pofile
+pofile: po.pofile
+endif
+
+ifneq ("$(CFLOW_CMD)", "")
+tools.cflow: libdm.cflow lib.cflow
+daemons.cflow: tools.cflow
+cflow: include.cflow
+endif
+
+ifneq ("@CSCOPE_CMD@", "")
+cscope.out:
+	@CSCOPE_CMD@ -b -R -s$(top_srcdir)
+all: cscope.out
+endif
+DISTCLEAN_TARGETS += cscope.out
+
+check check_cluster check_local unit: all
+	$(MAKE) -C test $(@)
+
+install_system_dirs:
+	$(INSTALL_DIR) $(DESTDIR)$(DEFAULT_SYS_DIR)
+	$(INSTALL_ROOT_DIR) $(DESTDIR)$(DEFAULT_ARCHIVE_DIR)
+	$(INSTALL_ROOT_DIR) $(DESTDIR)$(DEFAULT_BACKUP_DIR)
+	$(INSTALL_ROOT_DIR) $(DESTDIR)$(DEFAULT_CACHE_DIR)
+	$(INSTALL_ROOT_DIR) $(DESTDIR)$(DEFAULT_LOCK_DIR)
+	$(INSTALL_ROOT_DIR) $(DESTDIR)$(DEFAULT_RUN_DIR)
+	$(INSTALL_ROOT_DATA) /dev/null $(DESTDIR)$(DEFAULT_CACHE_DIR)/.cache
+
+install_initscripts: 
+	$(MAKE) -C scripts install_initscripts
+
+install_systemd_units:
+	$(MAKE) -C scripts install_systemd_units
+
+LCOV_TRACES = libdm.info lib.info tools.info \
+	daemons/dmeventd.info daemons/clvmd.info
+CLEAN_TARGETS += $(LCOV_TRACES)
+
+ifneq ("$(LCOV)", "")
+.PHONY: lcov-reset lcov lcov-dated $(LCOV_TRACES)
+
+ifeq ($(MAKECMDGOALS),lcov-dated)
+LCOV_REPORTS_DIR := lcov_reports-$(shell date +%Y%m%d%k%M%S)
+lcov-dated: lcov
+else
+LCOV_REPORTS_DIR := lcov_reports
+endif
+
+lcov-reset:
+	$(LCOV) --zerocounters $(addprefix -d , $(basename $(LCOV_TRACES)))
+
+# maybe use subdirs processing to create tracefiles...
+$(LCOV_TRACES):
+	$(LCOV) -b $(basename $@) \
+		-d $(basename $@) -c -o - | $(SED) \
+		-e "s/\(dmeventd_lvm.[ch]\)/plugins\/lvm2\/\1/" \
+		-e "s/\(dmeventd_mirror.c\)/plugins\/mirror\/\1/" \
+		-e "s/\(dmeventd_snapshot.c\)/plugins\/snapshot\/\1/" \
+		>$@
+
+ifneq ("$(GENHTML)", "")
+lcov: $(LCOV_TRACES)
+	$(RM) -r $(LCOV_REPORTS_DIR)
+	$(MKDIR_P) $(LCOV_REPORTS_DIR)
+	for i in $(LCOV_TRACES); do \
+		test -s $$i && lc="$$lc $$i"; \
+	done; \
+	test -z "$$lc" || $(GENHTML) -p @abs_top_builddir@ \
+		-o $(LCOV_REPORTS_DIR) $$lc
+endif
+
+endif
+
+ifeq ("$(TESTING)", "yes")
+# testing and report generation
+RUBY=ruby1.9 -Ireport-generators/lib -Ireport-generators/test
+
+.PHONEY: unit-test ruby-test test-programs
+
+# FIXME: put dependencies on libdm and liblvm
+# FIXME: Should be handled by Makefiles in subdirs, not here at top level.
+test-programs:
+	cd unit-tests/regex && $(MAKE)
+	cd unit-tests/datastruct && $(MAKE)
+	cd unit-tests/mm && $(MAKE)
+
+unit-test: test-programs
+	$(RUBY) report-generators/unit_test.rb $(shell find . -name TESTS)
+	$(RUBY) report-generators/title_page.rb
+
+memcheck: test-programs
+	$(RUBY) report-generators/memcheck.rb $(shell find . -name TESTS)
+	$(RUBY) report-generators/title_page.rb
+
+ruby-test:
+	$(RUBY) report-generators/test/ts.rb
+endif

README

@@ -1,2 +1,27 @@
-This is pretty much empty so far...if you can't see subdirectories,
-try 'cvs -f update'
+This tree contains the LVM2 and device-mapper tools and libraries.
+
+For more information about LVM2 read the changelog in the WHATS_NEW file.
+Installation instructions are in INSTALL.
+
+There is no warranty - see COPYING and COPYING.LIB.
+
+Tarballs are available from:
+  ftp://sources.redhat.com/pub/lvm2/
+
+To access the CVS tree use:
+  cvs -d :pserver:cvs@sources.redhat.com:/cvs/lvm2 login
+  CVS password: cvs
+  cvs -d :pserver:cvs@sources.redhat.com:/cvs/lvm2 co LVM2
+
+Mailing list for general discussion related to LVM2:
+  linux-lvm@redhat.com
+  Subscribe from https://www.redhat.com/mailman/listinfo/linux-lvm
+
+Mailing list for LVM2 development, patches and commits:
+  lvm-devel@redhat.com
+  Subscribe from https://www.redhat.com/mailman/listinfo/linux-lvm
+
+Mailing list for device-mapper development, including kernel patches
+and multipath-tools:
+  dm-devel@redhat.com
+  Subscribe from https://www.redhat.com/mailman/listinfo/dm-devel

VERSION

@@ -0,0 +1 @@
+2.02.92(2)-cvs (2012-02-20)

VERSION_DM

@@ -0,0 +1 @@
+1.02.71-cvs (2012-02-20)

WHATS_NEW_DM

@@ -0,0 +1,757 @@
+Version 1.02.71 - 20th February 2012
+====================================
+  Switch to using built-in blkid in 13-dm-disk.rules.
+  Add "watch" rule to 13-dm-disk.rules.
+  Detect failing fifo and skip 20s retry communication period.
+  Add DM_DEFAULT_NAME_MANGLING_MODE environment variable as an override.
+  Add dm_lib_init to automatically initialise device-mapper library on load.
+  Replace any '\' char with '\\' in table specification on input.
+  Add mangle command to dmsetup to provide renaming to correct mangled form.
+  Add 'mangled_name' and 'unmangled_name' fields to dmsetup info -c -o.
+  Add --manglename option to dmsetup to select the name mangling mode.
+  Add dm_task_get_name_mangled/unmangled to libdevmapper.
+  Mangle device name on dm_task_set_name/newname call if necessary.
+  Add dm_set/get_name_mangling_mode to set/get name mangling in libdevmapper.
+  Add configure --with-default-name-mangling for udev-friendly dev name charset.
+  Test for parsed words in _umount() dmeventd snapshot plugin.
+  Fix memory leak in fail path of parse_loop_device_name() in dmsetup.
+  Check for missing reply_uuid in dm_event_get_registered_device().
+  Check for allocation failure in dmeventd restart().
+  Add few missing allocation failures tests in dmsetup.
+  Fix potential risk of writing in front of buffer in _sysfs_get_dm_name().
+
+Version 1.02.70 - 12th February 2012
+====================================
+  Fix dm_event_get_version() check.
+  Add pointer test for dependency check in _add_dev().
+  Validate name and uuid params of dm_tree_add_new_dev_with_udev_flags().
+  Do not crash for dm_report_init() sort_key == NULL and behave like "".
+  Return error for failing allocation in dm_asprintf().
+  Add missing test for failing allocation in dm_realloc() code.
+  Add test for memory allocation failures in regex matcher code.
+  Simplify dm_task_set_geometry() and use dm_asprintf().
+  Set all parameters to 0 for dm_get_next_target() for NULL return.
+  Fix fd resource leak in error path for _udev_notify_sem_create().
+  Leave space for '\0' for readline() call in _sysfs_get_kernel_name().
+
+Version 1.02.69 - 1st February 2012
+===================================
+  Clean up dmeventd systemd unit ordering and requirements.
+
+Version 1.02.68 - 26th January 2012
+===================================
+  Reset all members of info struct in dm_tree_add_new_dev_with_udev_flags.
+  Add dmsetup wipe_table to replace table with one that uses error target.
+  Add 'blkdevname' and 'blkdevs_used' fields to dmsetup info -c -o.
+  Add 'blkdevname' option to dmsetup ls --tree to see block device names.
+  Add -o devno/blkdevname/devname to dmsetup deps and ls.
+  Add dm_device_get_name to get map name or block device name for given devno.
+  Remove empty devices when clearing left-over inactive tables in deptree.
+  Add dm_uuid_prefix/dm_set_uuid_prefix to override hard-coded LVM- prefix.
+  Improve dmsetup man page description of readahead parameter.
+  Use sysfs to set/get readahead if possible.
+  Fix lvm2-monitor init script to use normalized output when using vgs.
+  Add test for max length (DM_MAX_TYPE_NAME) of target type name.
+  Include a copy of kernel DM documentation in doc/kernel.
+  Improve man page style for dmsetup and mention more targets.
+  Fix _get_proc_number to be tolerant of malformed /proc/misc entries.
+  Fix missing thread list manipulation protection in dmeventd.
+  Add ExecReload to dm-event.service for systemd to reload dmeventd properly.
+  Add dm_config_tree_find_str_allow_empty and dm_config_find_str_allow_empty.
+  Fix compile-time pool memory locking with DEBUG_MEM.
+  Fix valgrind error reports in free of pool chunks with DEBUG_MEM.
+  Align size of structure chunk for fast pool allocator to 8 bytes.
+  Simplify some pointer operations in dm_free_aux() debug code.
+  Remove unused dbg_malloc.h file from source tree.
+  Cleanup backtraces for _create_and_load_v4().
+  Fix alignment warning in bitcount calculation for raid segment.
+  Allocate dm_tree structure from dm_tree pool.
+  Update debug logging for _resume_node.
+  Add functions to support thin provisioning target.
+  Improve libdm-config error path reporting.
+  Update dmsetup resume man with --addnodeonresume/create options.
+  Add dependency for dm man pages to man subdirectory make all target.
+  Add dm_tree_retry_remove to use retry logic for device removal in a dm_tree.
+  Add dm_device_has_mounted_fs fn to check mounted filesystem on a device.
+  Add dm_device_has_holders fn to to check use of the device by another device.
+  Add dm_sysfs_dir to libdevmapper to retrieve sysfs location set.
+  Add dm_set_sysfs_dir to libdevmapper to set sysfs location.
+  Add --retry option for dmsetup remove to retry removal if not successful.
+  Add dm_task_retry_remove fn to use retry logic for device removal.
+  Remove unused passed parameters for _mirror_emit_segment_line().
+  Add dm_config and string character escaping functions to libdevmapper.
+  Mark unreleased memory pools as internal error.
+
+Version 1.02.67 - 19th August 2011
+==================================
+  Add dm_tree_node_add_null_area for temporarily-missing raid devs tracked.
+
+Version 1.02.66 - 12th August 2011
+==================================
+  Release geometry buffer in dm_task_destroy.
+  Update udev rules to skip DM flags decoding for removed devices.
+  Add compile-time pool memory locking options (to debug shared VG structs).
+  Remove device name prefix from dmsetup line output if -j & -m or -u supplied.
+  Remove support for the original version 1 dm ioctls.
+  Add missing check for allocation failure _create_dir_recursive().
+  Add support for systemd file descriptor handover in dmeventd.
+  Fix memory leak in dmsetup _message() memory allocation error path.
+  Use new oom killer adjustment interface (oom_score_adj) when available.
+  Add systemd unit files for dmeventd.
+  Fix read-only identical table reload supression.
+
+Version 1.02.65 - 8th July 2011
+===============================
+  Remove dev name prefix from dmsetup line output if exactly one dev requested.
+  Report internal error if suspending a device using an already-suspended dev.
+  Report error if a table load requiring target parameters has none supplied.
+  Add dmsetup --checks and dm_task_enable_checks framework to validate ioctls.
+  Add age_in_minutes parameter to dmsetup udevcomplete_all.
+  Return immediately from dm_lib_exit() if called more than once.
+  Disable udev fallback by default and add --verifyudev option to dmsetup.
+  Report internal error if any table is loaded while any dev is known suspended.
+  Add dm_get_suspended_counter() for number of devs in suspended state by lib.
+  Fix "all" report field prefix matching to include label fields with pv_all.
+  Delay resuming new preloaded mirror devices with core logs in deptree code.
+  Accept new kernel version 3 uname formats in initialisation.
+
+Version 1.02.64 - 29th April 2011
+==================================
+  Require libudev >= 143 when compiling with udev support.
+  Use word alignment for dm_pool_strdup() and dm_pool_strndup().
+  Use dm_snprintf() to fix signedness warning in dm_set_dev_dir().
+  Use unsigned loop counter to fix signedness warning in _other_node_ops().
+  Fix const cast in dmsetup calls of dm_report_field_string().
+  Streamline /dev/mapper/control node code for common cases.
+  Use hard-coded dm control node device number for 2.6.36 kernels and above.
+  Improve stack debug reporting in dm_task_create().
+  Fallback to control node creation only if node doesn't exist yet.
+  Change dm_hash binary functions to take void *key instead of char *.
+  Fix uninitialised memory use with empty params in _reload_with_suppression_v4.
+  Lower severity of selabel_lookup and matchpathcon failure to log_debug.
+  Add test for failed allocation from dm_task_set_uuid() in dmeventd.
+  Add dm_event_get_version to dmeventd for use with -R.
+  Avoid dmeventd core dumps when handling request with unknown command ID.
+  Have dmeventd -R start up even when no existing copy is running.
+  Accept multiple mapped device names on many dmsetup command lines.
+  Fix dm_udev_wait calls in dmsetup to occur before readahead display not after.
+  Include an implicit dm_task_update_nodes() within dm_udev_wait().
+  Fix _create_and_load_v4 not to lose the --addnodeoncreate setting (1.02.62).
+  Add inactive table query support for kernel driver >= 4.11.6 (RHEL 5.7).
+  Log debug open_count in _node_has_closed_parents().
+  Add a const to dm_report_field_string() data parameter.
+
+Version 1.02.63 - 9th February 2011
+===================================
+  Reinstate DEBUG_MEM as it's part of the API. (1.02.62)
+
+Version 1.02.62 - 4th February 2011
+===================================
+  Add configure --with-device-nodes-on=create for previous behaviour.
+  Move creation of device nodes from 'create' to 'resume'.
+  Add --addnodeonresume and --addnodeoncreate options to dmsetup.
+  Add dm_task_set_add_node to libdevmapper to control dev node creation time.
+  Add dm_task_secure_data to libdevmapper to wipe ioctl buffers in kernel.
+  Log debug message when expected uevent is not generated.
+  Only compile memory debugging code when DEBUG_MEM is set.
+  Set DM_UDEV_DISABLE_OTHER_RULES_FLAG for suspended DM devices in udev rules.
+  Begin a new pool object for each row in _output_as_rows() correctly.
+
+Version 1.02.61 - 10th January 2011
+===================================
+  Add DM_COOKIE_AUTO_CREATE to libdevmapper.h.
+  Export DM_CONTROL_NODE_UMASK and use it while creating /dev/mapper/control.
+
+Version 1.02.60 - 20th December 2010
+====================================
+  Check for unlink failure in remove_lockfile() in dmeventd.
+  Use dm_free for dm_malloc-ed areas in _clog_ctr/_clog_dtr in cmirrord.
+  Use char* arithmetic in _process_all() & _targets() in dmsetup.
+  Change dm_regex_create() API to accept const char * const *patterns.
+  Add new dm_prepare_selinux_context fn to libdevmapper and use it throughout.
+  Detect existence of new SELinux selabel interface during configure.
+
+Version 1.02.59 - 6th December 2010
+===================================
+  Add backtraces to _process_mapper_dir and  _create_and_load_v4 error paths.
+  Remove superfluous checks for NULL before calling dm_free.
+
+Version 1.02.58 - 22nd November 2010
+====================================
+  Fix _output_field crash from field_id free with DEBUG_MEM. (1.02.57)
+
+Version 1.02.57 - 8th November 2010
+===================================
+  Fix regex optimiser not to ignore RHS of OR nodes in _find_leftmost_common.
+  Add dmeventd -R to restart dmeventd without losing monitoring state. (1.02.56)
+  Fix memory leak of field_id in _output_field function.
+  Allocate buffer for reporting functions dynamically to support long outputs.
+
+Version 1.02.56 - 25th October 2010
+===================================
+  Return const pointer from dm_basename() in libdevmapper.
+  Implement dmeventd -R to restart without state loss.
+  Add dm_zalloc and use it and dm_pool_zalloc throughout.
+  Add --setuuid to dmsetup rename.
+  Add dm_task_set_newuuid to set uuid of mapped device post-creation.
+
+Version 1.02.55 - 24th September 2010
+=====================================
+  Fix the way regions are marked complete to avoid slow --nosync cmirror I/O.
+  Add DM_REPORT_FIELD_TYPE_ID_LEN to libdevmapper.h.
+
+Version 1.02.54 - 18th August 2010
+==================================
+  Fix dm-mod autoloading logic to not assume control node is set correctly.
+  Add dmeventd/executable to lvm.conf to test alternative dmeventd.
+  Export dm_event_handler_set_dmeventd_path to override built-in dmeventd path.
+  Generate libdevmapper-event exported symbols.
+  Remove superfluous NULL pointer tests before dm_free from dmeventd.
+  Assume dm-mod autoloading support is in kernel 2.6.36 and higher, not 2.6.35.
+  Fix udev rules to support udev database content generated by older rules.
+  Reinstate detection of inappropriate uevent with DISK_RO set and suppress it.
+  Fix regex ttree off-by-one error.
+  Add --enable-valgrind-pool to configure.
+  Fix segfault in regex matcher with characters of ordinal value > 127.
+  Fix 'void*' arithmetic warnings in dbg_malloc.c and libdm-iface.c.
+  Wait for node creation before displaying debug info in dmsetup.
+  Fix return status 0 for "dmsetup info -c -o help".
+  Add check for kernel semaphore support and disable udev_sync if not available.
+
+Version 1.02.53 - 28th July 2010
+================================
+  Revert failed table load preparation after "create, load and resume".
+  Switch dmeventd to use dm_create_lockfile and drop duplicate code.
+  Add dm_create_lockfile to libdm to handle pidfiles for all daemons.
+  Replace lookup with next in struct dfa_state & calculate states on demand.
+  Improve the regex matcher, reducing the number of charset nodes used.
+  Add dm_regex_fingerprint to facilitate regex testing.
+  Skip ffs(0) in _test_word in bitset functions.
+  Use "nowatch" udev rule for inappropriate devices.
+
+Version 1.02.52 - 6th July 2010
+===============================
+  Fix dmlosetup snprintf %llu compiler warning.
+  Add parentheses to some libdevmapper.h macro arguments.
+  Add printf format attributes to dm_{sn,as}printf and fix a caller.
+  Move dmeventd man page from install_lvm2 to install_device-mapper. (1.02.50)
+
+Version 1.02.51 - 30th June 2010
+================================
+  Generate libdevmapper exported symbols from header file.
+
+Version 1.02.50 - 23rd June 2010
+================================
+  Fix INTERNAL_ERROR typo in ioctl iface unknown task message.
+  Fix udev rules to handle spurious events properly.
+  Use C99 [] not [0] in dm_ulog_request struct to avoid abort when fortified.
+  Allow use of devmapper header file in C++ mode (extern "C" and __typeof__).
+  Add dmeventd man page.
+
+Version 1.02.49 - 4th June 2010
+===============================
+  Support autoloading of dm-mod module for kernels from 2.6.35.
+  Document 'clear' in dmsetup man page.
+  Fix semctl parameter (union) to avoid misaligned parameter on some arches.
+  Add dm_tree_node_set_presuspend_node() to presuspend child when deactivating.
+  Initial support for replicator target.
+
+Version 1.02.48 - 17th May 2010
+================================
+  Use -d to control level of messages sent to syslog by dmeventd.
+  Change -d to -f to run dmeventd in foreground.
+  Do not print encryption key in message debug output (cryptsetup luksResume).
+  Fix dmeventd static build library dependencies.
+  Fix udev flags on remove in create_and_load error path.
+
+Version 1.02.47 - 30th April 2010
+=================================
+  Add support for new IMPORT{db} udev rule.
+  Add DM_UDEV_PRIMARY_SOURCE_FLAG udev flag to recognize proper DM events.
+  Also include udev libs in libdevmapper.pc when udev_sync is enabled.
+  Cache bitset locations to speed up _calc_states.
+  Add a regex optimisation pass for shared prefixes and suffixes.
+  Add dm_bit_and and dm_bitset_equal to libdevmapper.
+  Simplify dm_bitset_create.
+  Speed up dm_bit_get_next with ffs().
+
+Version 1.02.46 - 14th April 2010
+=================================
+  Change dm_tree_deactivate_children to fail if device is open.
+  Wipe memory buffers for dm-ioctl parameters before releasing.
+  Strictly require libudev if udev_sync is used.
+  Add support for ioctl's DM_UEVENT_GENERATED_FLAG.
+
+Version 1.02.45 - 9th March 2010
+================================
+  Add --showkeys parameter description to dmsetup man page.
+  Add --help option as synonym for help command.
+
+Version 1.02.44 - 15th February 2010
+====================================
+  Add DM_UDEV_DISABLE_LIBRARY_FALLBACK udev flag to rely on udev only.
+  Export dm_udev_create_cookie function to create new cookies on demand.
+  Add --udevcookie, udevcreatecookie and udevreleasecookie to dmsetup.
+  Set udev state automatically instead of using DM_UDEV_DISABLE_CHECKING.
+
+Version 1.02.43 - 21st January 2010
+===================================
+  Remove bitset, hash and pool headers superceded by libdevmapper.h.
+  Fix off-by-one error causing bad cluster mirror table construction.
+
+Version 1.02.42 - 14th January 2010
+===================================
+  Add support for the "snapshot-merge" kernel target (2.6.33-rc1).
+  Introduce a third activation_priority level in dm_tree_activate_children.
+
+Version 1.02.41 - 12th January 2010
+===================================
+  If DM_UDEV_DISABLE_CHECKING is set in environment, disable udev warnings.
+  Add dm_tree_add_dev_with_udev_flags to provide wider support for udev flags.
+  Add --noudevrules option for dmsetup to disable /dev node management by udev.
+  Fix 'dmsetup info -c -o all' to show all fields.
+  Return errors if dm_tree_*_children functions fail.
+  Fix coredump and memory leak for 'dmsetup help -c'.
+  Disable udev rules for change events with DISK_RO set.
+
+Version 1.02.40 - 19th November 2009
+====================================
+  Fix install_device-mapper Makefile target to not build dmeventd plugins.
+  Support udev flags even when udev_sync is disabled or not compiled in.
+  Remove 'last_rule' from udev rules: honour DM_UDEV_DISABLE_OTHER_RULES_FLAG.
+  Add dmsetup --inactive support.
+  Add dm_task_query_inactive_table to libdevmapper for kernel driver >= 4.16.
+  Fix hash lookup segfault when keys compared are different lengths.
+
+Version 1.02.39 - 26th October 2009
+===================================
+  Remove strict default permissions for DM devices from 95-dm-notify.rules.
+  Add dmsetup udevflags command to decode udev flags in given cookie value.
+  Support udev flags in libdevmapper incl. dm_tree_add_new_dev_with_udev_flags.
+  Make libdm ABI consistent when built with/without selinux support.
+
+Version 1.02.38 - 25th September 2009
+=====================================
+  Export DM_DEV_DIR_UMASK, the default umask for /dev directories created.
+  Handle any path supplied to dm_task_set_name by looking up in /dev/mapper.
+  Add several examples to 12-dm-permissions.rules.
+  Add splitname and --yes to dmsetup man page.
+  Fix _mirror_emit_segment_line return code.
+  Fix dmeventd _temporary_log_fn parameters. (2.02.50)
+
+Version 1.02.37 - 15th September 2009
+=====================================
+  Add dmsetup manpage entries for udevcomplete_all and udevcookies.
+  Check udev is running when processing cookies and retain state internally.
+  Add y|--yes option to dmsetup for default 'yes' answer to prompts.
+  Fix tools Makefile to process dmsetup sources separately.
+  Restore umask when device node creation fails.
+  Check kernel vsn to use 'block_on_error' or 'handle_errors' in mirror table.
+  Add dm-log-userspace.h to tree for cmirrord builds.
+
+Version 1.02.36 - 6th August 2009
+=================================
+  Add udevcookies, udevcomplete, udevcomplete_all and --noudevwait to dmsetup.
+  Add libdevmapper functions to support synchronisation with udev.
+
+Version 1.02.35 - 28th July 2009
+================================
+  Add LOG_LINE_WITH_ERRNO macro.
+  Use log_error macro consistently throughout in place of log_err.
+
+Version 1.02.34 - 15th July 2009
+================================
+  Use _exit() not exit() after forking to avoid flushing libc buffers twice.
+  Rename plog macro to LOG_LINE & add LOG_MESG variant for dm_dump_memory_debug.
+  Change plog to use dm_log_with_errno unless deprecated dm_log_init was used.
+  Add dm_log_with_errno and dm_log_with_errno_init, deprecating the old fns.
+  Fix whitespace in linear target line to fix identical table line detection.
+  Add device number to more log messages during activation.
+
+Version 1.02.33 - 30th June 2009
+================================
+  Don't fallback to default major number: use dm_task_set_major_minor. (1.02.31)
+  Do not fork daemon when dmeventd cannot be found.
+  Add crypt target handling to libdevmapper tree nodes.
+  Add splitname command to dmsetup.
+  Add subsystem, vg_name, lv_name, lv_layer fields to dmsetup reports.
+  Make mempool optional in dm_split_lvm_name().
+
+Version 1.02.32 - 21st May 2009
+===============================
+  Only generate libdevmapper.a when configured to link statically.
+  Export dm_tree_node_size_changed() from libdevmapper.
+  Propagate the table size_changed property up the dm device tree.
+  Detect failure to free memory pools when releasing the library.
+  Fix segfault when getopt processes dmsetup -U, -G and -M options.
+
+Version 1.02.31 - 3rd March 2009
+================================
+  If kernel supports only one dm major number, use in place of any supplied.
+
+Version 1.02.30 - 26th January 2009
+====================================
+  Add "all" field to reports expanding to all fields of report type.
+  Enforce device name length and character limitations in libdm.
+  Replace _dm_snprintf with EMIT_PARAMS macro for creating target lines.
+
+Version 1.02.29 - 10th November 2008
+====================================
+  Merge device-mapper into the LVM2 tree.
+  Split out dm-logging.h from log.h.
+  Use lvm-types.h.
+  Add usrsbindir to configure.
+
+Version 1.02.28 - 18th September 2008
+=====================================
+  Only resume devices in dm_tree_preload_children if size changes.
+  Extend deptree buffers so the largest possible device numbers fit.
+  Generate versioned libdevmapper-event.so.
+  Underline longer report help text headings.
+
+Version 1.02.27 - 25th June 2008
+================================
+  Align struct memblock in dbg_malloc for sparc.
+  Add --unquoted and --rows to dmsetup.
+  Avoid compiler warning about cast in dmsetup.c's OFFSET_OF macro.
+  Fix inverted no_flush debug message.
+  Remove --enable-jobs from configure. (Set at runtime instead.)
+  Bring configure.in and list.h into line with the lvm2 versions.
+
+Version 1.02.26 - 6th June 2008
+===============================
+  Initialise params buffer to empty string in _emit_segment.
+  Skip add_dev_node when ioctls disabled.
+  Make dm_hash_iter safe against deletion.
+  Accept a NULL pointer to dm_free silently.
+  Add tables_loaded, readonly and suspended columns to reports.
+  Add --nameprefixes to dmsetup.
+  Add field name prefix option to reporting functions.
+  Calculate string size within dm_pool_grow_object.
+
+Version 1.02.25 - 10th April 2008
+=================================
+  Remove redundant if-before-free tests.
+  Use log_warn for reporting field help text instead of log_print.
+  Change cluster mirror log type name (s/clustered_/clustered-/)
+
+Version 1.02.24 - 20th December 2007
+====================================
+  Fix deptree to pass new name to _resume_node after a rename.
+  Suppress other node operations if node is deleted.
+  Add node operation stack debug messages.
+  Report error when empty device name passed to readahead functions.
+  Fix minimum readahead debug message.
+
+Version 1.02.23 - 5th December 2007
+===================================
+  Update dm-ioctl.h after removal of compat code.
+  Add readahead support to libdevmapper and dmsetup.
+  Fix double free in a libdevmapper-event error path.
+  Fix configure --with-dmeventd-path substitution.
+  Allow a DM_DEV_DIR environment variable to override /dev in dmsetup.
+  Create a libdevmapper.so.$LIB_VERSION symlink within the build tree.
+  Avoid static link failure with some SELinux libraries that require libpthread.
+  Remove obsolete dmfs code from tree and update INSTALL.
+
+Version 1.02.22 - 21st August 2007
+==================================
+  Fix inconsistent licence notices: executables are GPLv2; libraries LGPLv2.1.
+  Update to use autoconf 2.61, while still supporting 2.57.
+  Avoid repeated dm_task free on some dm_event_get_registered_device errors.
+  Introduce log_sys_* macros from LVM2.
+  Export dm_fclose and dm_create_dir; remove libdm-file.h.
+  Don't log EROFS mkdir failures in _create_dir_recursive (for LVM2).
+  Add fclose wrapper dm_fclose that catches write failures (using ferror).
+
+Version 1.02.21 - 13th July 2007
+================================
+  Introduce _LOG_STDERR to send log_warn() messages to stderr not stdout.
+  Fix dmsetup -o devno string termination. (1.02.20)
+
+Version 1.02.20 - 15th June 2007
+================================
+  Fix default dmsetup report buffering and add --unbuffered.
+  Add tree-based and dependency fields to dmsetup reports.
+
+Version 1.02.19 - 27th April 2007
+=================================
+  Standardise protective include file #defines.
+  Add regex functions to library.
+  Avoid trailing separator in reports when there are hidden sort fields.
+  Fix segfault in 'dmsetup status' without --showkeys against crypt target.
+  Deal with some more compiler warnings.
+  Introduce _add_field() and _is_same_field() to libdm-report.c.
+  Fix some libdevmapper-event and dmeventd memory leaks.
+  Remove unnecessary memset() return value checks.
+  Fix a few leaks in reporting error paths. [1.02.15+]
+
+Version 1.02.18 - 13th February 2007
+====================================
+  Improve dmeventd messaging protocol: drain pipe and tag messages.
+
+Version 1.02.17 - 29th January 2007
+===================================
+  Add recent reporting options to dmsetup man page.
+  Revise some report fields names.
+  Add dmsetup 'help' command and update usage text.
+  Use fixed-size fields in report interface and reorder.
+
+Version 1.02.16 - 25th January 2007
+===================================
+  Add some missing close() and fclose() return value checks.
+  Migrate dmsetup column-based output over to new libdevmapper report framework.
+  Add descriptions to reporting field definitions.
+  Add a dso-private variable to dmeventd dso interface.
+  Add dm_event_handler_[gs]et_timeout functions.
+  Streamline dm_report_field_* interface.
+  Add cmdline debug & version options to dmeventd.
+  Add DM_LIB_VERSION definition to configure.h.
+  Suppress 'Unrecognised field' error if report field is 'help'.
+  Add --separator and --sort to dmsetup (unused).
+  Make alignment flag optional when specifying report fields.
+
+Version 1.02.15 - 17th January 2007
+===================================
+  Add basic reporting functions to libdevmapper.
+  Fix a malloc error path in dmsetup message.
+  More libdevmapper-event interface changes and fixes.
+  Rename dm_saprintf() to dm_asprintf().
+  Report error if NULL pointer is supplied to dm_strdup_aux().
+  Reinstate dm_event_get_registered_device.
+
+Version 1.02.14 - 11th January 2007
+===================================
+  Add dm_saprintf().
+  Use CFLAGS when linking so mixed sparc builds can supply -m64.
+  Add dm_tree_use_no_flush_suspend().
+  Lots of dmevent changes including revised interface.
+  Export dm_basename().
+  Cope with a trailing space when comparing tables prior to possible reload.
+  Fix dmeventd to cope if monitored device disappears.
+
+Version 1.02.13 - 28 Nov 2006
+=============================
+  Update dmsetup man page (setgeometry & message).
+  Fix dmsetup free after getline with debug.
+  Suppress encryption key in 'dmsetup table' output unless --showkeys supplied.
+
+Version 1.02.12 - 13 Oct 2006
+=============================
+  Avoid deptree attempting to suspend a device that's already suspended.
+
+Version 1.02.11 -  12 Oct 2006
+==============================
+  Add suspend noflush support.
+  Add basic dmsetup loop support.
+  Switch dmsetup to use dm_malloc and dm_free.
+
+Version 1.02.10 - 19 Sep 2006
+=============================
+  Add dm_snprintf(), dm_split_words() and dm_split_lvm_name() to libdevmapper.
+  Reorder mm bounds_check code to reduce window for a dmeventd race.
+
+Version 1.02.09 - 15 Aug 2006
+=============================
+  Add --table argument to dmsetup for a one-line table.
+  Abort if errors are found during cmdline option processing.
+  Add lockfs indicator to debug output.
+
+Version 1.02.08 - 17 July 2006
+==============================
+  Append full patch to check in emails.
+  Avoid duplicate dmeventd subdir with 'make distclean'.
+  Update dmsetup man page.
+  Add --force to dmsetup remove* to load error target.
+  dmsetup remove_all also performs mknodes.
+  Don't suppress identical table reloads if permission changes.
+  Fix corelog segment line.
+  Suppress some compiler warnings.
+
+Version 1.02.07 - 11 May 2006
+=============================
+  Add DM_CORELOG flag to dm_tree_node_add_mirror_target().
+  Avoid a dmeventd compiler warning.
+
+Version 1.02.06 - 10 May 2006
+=============================
+  Move DEFS into configure.h.
+  Fix leaks in error paths found by coverity.
+  Remove dmsetup line buffer limitation.
+
+Version 1.02.05 - 19 Apr 2006
+=============================
+  Separate install_include target in makefiles.
+  Separate out DEFS from CFLAGS.
+  Support pkg-config.
+  Check for libsepol.
+
+Version 1.02.04 - 14 Apr 2006
+=============================
+  Bring dmsetup man page up-to-date.
+  Use name-based device refs if kernel doesn't support device number refs.
+  Fix memory leak (struct dm_ioctl) when struct dm_task is reused.
+  If _create_and_load_v4 fails part way through, revert the creation.
+  dmeventd thread/fifo fixes.
+  Add file & line to dm_strdup_aux().
+  Add setgeometry.
+
+Version 1.02.03 - 7 Feb 2006
+============================
+  Add exported functions to set uid, gid and mode.
+  Rename _log to dm_log and export.
+  Add dm_tree_skip_lockfs.
+  Fix dm_strdup debug definition.
+  Fix hash function to avoid using a negative array offset.
+  Don't inline _find in hash.c and tidy signed/unsigned etc.
+  Fix libdevmapper.h #endif.
+  Fix dmsetup version driver version.
+  Add sync, nosync and block_on_error mirror log parameters.
+  Add hweight32.
+  Fix dmeventd build.
+
+Version 1.02.02 - 2 Dec 2005
+============================
+  dmeventd added.
+  Export dm_task_update_nodes.
+  Use names instead of numbers in messages when ioctls fail.
+
+Version 1.02.01 - 23 Nov 2005
+=============================
+  Resume snapshot-origins last.
+  Drop leading zeros from dm_format_dev.
+  Suppress attempt to reload identical table.
+  Additional LVM- prefix matching for transitional period.
+
+Version 1.02.00 - 10 Nov 2005
+=============================
+  Added activation functions to library.
+  Added return macros.
+  Also suppress error if device doesn't exist with DM_DEVICE_STATUS.
+  Export dm_set_selinux_context().
+  Add dm_driver_version().
+  Added dependency tree functions to library.
+  Added hash, bitset, pool, dbg_malloc to library.
+  Added ls --tree to dmsetup.
+  Added dmsetup --nolockfs support for suspend/reload.
+
+Version 1.01.05 - 26 Sep 2005
+=============================
+  Resync list.h with LVM2.
+  Remember increased buffer size and use for subsequent calls.
+  On 'buffer full' condition, double buffer size and repeat ioctl.
+  Fix termination of getopt_long() option array.
+  Report 'buffer full' condition with v4 ioctl as well as with v1.
+
+Version 1.01.04 - 2 Aug 2005
+============================
+  Fix dmsetup ls -j and status --target with empty table.
+
+Version 1.01.03 - 13 Jun 2005
+=============================
+  Use matchpathcon mode parameter.
+  Fix configure script to re-enable selinux.
+
+Version 1.01.02 - 17 May 2005
+=============================
+  Call dm_lib_exit() and dm_lib_release() automatically now.
+  Add --target <target_type> filter to dmsetup table/status/ls.
+  Add --exec <command> to dmsetup ls.
+  Fix dmsetup getopt_long usage.
+
+Version 1.01.01 - 29 Mar 2005
+=============================
+  Update dmsetup man page.
+  Drop-in devmap_name replacement.
+  Add option to compile without ioctl for testing.
+  Fix DM_LIB_VERSION sed.
+
+Version 1.01.00 - 17 Jan 2005
+=============================
+  Add dm_task_no_open_count() to skip getting open_count.
+
+Version 1.00.21 - 7 Jan 2005
+============================
+  Fix /proc/devices parsing.
+
+Version 1.00.20 - 6 Jan 2005
+============================
+  Attempt to fix /dev/mapper/control transparently if it's wrong.
+  Configuration-time option for setting uid/gid/mode for /dev/mapper nodes.
+  Update kernel patches for 2.4.27/2.4.28-pre-4 (includes minor fixes).
+  Add --noheadings columns option for colon-separated dmsetup output.
+  Support device referencing by uuid or major/minor.
+  Warn if kernel data didn't fit in buffer.
+  Fix a printf.
+
+Version 1.00.19 - 3 July 2004
+=============================
+  More autoconf fixes.
+  Fix a dmsetup newline.
+  Fix device number handling for 2.6 kernels.
+
+Version 1.00.18 - 20 Jun 2004
+=============================
+  Fix a uuid free in libdm-iface.
+  Fix a targets string size calc in driver.
+  Add -c to dmsetup for column-based output.
+  Add target message-passing ioctl.
+
+Version 1.00.17 - 17 Apr 2004
+=============================
+  configure --with-owner= --with-group= to avoid -o and -g args to 'install'
+  Fix library selinux linking.
+
+Version 1.00.16 - 16 Apr 2004
+=============================
+  Ignore error setting selinux file context if fs doesn't support it.
+
+Version 1.00.15 - 7 Apr 2004
+============================
+  Fix status overflow check in kernel patches.
+
+Version 1.00.14 - 6 Apr 2004
+============================
+  Fix static selinux build.
+
+Version 1.00.13 - 6 Apr 2004
+============================
+  Add some basic selinux support.
+
+Version 1.00.12 - 6 Apr 2004
+============================
+  Fix dmsetup.static install.
+
+Version 1.00.11 - 5 Apr 2004
+============================
+  configure --enable-static_link does static build in addition to dynamic.
+  Moved Makefile library targets definition into template.
+
+Version 1.00.10 - 2 Apr 2004
+============================
+  Fix DESTDIR handling.
+  Static build installs to dmsetup.static.
+  Basic support for internationalisation.
+  Minor Makefile tidy-ups/fixes.
+
+Version 1.00.09 - 31 Mar 2004
+=============================
+  Update copyright notices to Red Hat.
+  Move full mknodes functionality from dmsetup into libdevmapper.
+  Avoid sscanf %as for uClibc compatibility.
+  Cope if DM_LIST_VERSIONS is not defined.
+  Add DM_LIST_VERSIONS functionality to kernel patches.
+  Generate new kernel patches for 2.4.26-rc1.
+
+Version 1.00.08 - 27 Feb 2004
+=============================
+  Added 'dmsetup targets'.
+  Added event_nr support to 'dmsetup wait'.
+  Updated dmsetup man page.
+  Allow logging function to be reset to use internal one.
+  Bring log macros in line with LVM2 ones.
+  Added 'make install_static_lib' which installs libdevmapper.a.
+  Made configure/makefiles closer to LVM2 versions.
+  Fixed DESTDIR for make install/install_static_lib.
+  Updated README/INSTALL to reflect move to sources.redhat.com.
+  Updated autoconf files to 2003-06-17.

aclocal.m4

@@ -0,0 +1,171 @@
+# generated automatically by aclocal 1.11.1 -*- Autoconf -*-
+
+# Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
+# 2005, 2006, 2007, 2008, 2009  Free Software Foundation, Inc.
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY, to the extent permitted by law; without
+# even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+# PARTICULAR PURPOSE.
+
+# pkg.m4 - Macros to locate and utilise pkg-config.            -*- Autoconf -*-
+# serial 1 (pkg-config-0.24)
+# 
+# Copyright © 2004 Scott James Remnant <scott@netsplit.com>.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+#
+# As a special exception to the GNU General Public License, if you
+# distribute this file as part of a program that contains a
+# configuration script generated by Autoconf, you may include it under
+# the same distribution terms that you use for the rest of that program.
+
+# PKG_PROG_PKG_CONFIG([MIN-VERSION])
+# ----------------------------------
+AC_DEFUN([PKG_PROG_PKG_CONFIG],
+[m4_pattern_forbid([^_?PKG_[A-Z_]+$])
+m4_pattern_allow([^PKG_CONFIG(_PATH)?$])
+AC_ARG_VAR([PKG_CONFIG], [path to pkg-config utility])
+AC_ARG_VAR([PKG_CONFIG_PATH], [directories to add to pkg-config's search path])
+AC_ARG_VAR([PKG_CONFIG_LIBDIR], [path overriding pkg-config's built-in search path])
+
+if test "x$ac_cv_env_PKG_CONFIG_set" != "xset"; then
+	AC_PATH_TOOL([PKG_CONFIG], [pkg-config])
+fi
+if test -n "$PKG_CONFIG"; then
+	_pkg_min_version=m4_default([$1], [0.9.0])
+	AC_MSG_CHECKING([pkg-config is at least version $_pkg_min_version])
+	if $PKG_CONFIG --atleast-pkgconfig-version $_pkg_min_version; then
+		AC_MSG_RESULT([yes])
+	else
+		AC_MSG_RESULT([no])
+		PKG_CONFIG=""
+	fi
+fi[]dnl
+])# PKG_PROG_PKG_CONFIG
+
+# PKG_CHECK_EXISTS(MODULES, [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])
+#
+# Check to see whether a particular set of modules exists.  Similar
+# to PKG_CHECK_MODULES(), but does not set variables or print errors.
+#
+# Please remember that m4 expands AC_REQUIRE([PKG_PROG_PKG_CONFIG])
+# only at the first occurence in configure.ac, so if the first place
+# it's called might be skipped (such as if it is within an "if", you
+# have to call PKG_CHECK_EXISTS manually
+# --------------------------------------------------------------
+AC_DEFUN([PKG_CHECK_EXISTS],
+[AC_REQUIRE([PKG_PROG_PKG_CONFIG])dnl
+if test -n "$PKG_CONFIG" && \
+    AC_RUN_LOG([$PKG_CONFIG --exists --print-errors "$1"]); then
+  m4_default([$2], [:])
+m4_ifvaln([$3], [else
+  $3])dnl
+fi])
+
+# _PKG_CONFIG([VARIABLE], [COMMAND], [MODULES])
+# ---------------------------------------------
+m4_define([_PKG_CONFIG],
+[if test -n "$$1"; then
+    pkg_cv_[]$1="$$1"
+ elif test -n "$PKG_CONFIG"; then
+    PKG_CHECK_EXISTS([$3],
+                     [pkg_cv_[]$1=`$PKG_CONFIG --[]$2 "$3" 2>/dev/null`],
+		     [pkg_failed=yes])
+ else
+    pkg_failed=untried
+fi[]dnl
+])# _PKG_CONFIG
+
+# _PKG_SHORT_ERRORS_SUPPORTED
+# -----------------------------
+AC_DEFUN([_PKG_SHORT_ERRORS_SUPPORTED],
+[AC_REQUIRE([PKG_PROG_PKG_CONFIG])
+if $PKG_CONFIG --atleast-pkgconfig-version 0.20; then
+        _pkg_short_errors_supported=yes
+else
+        _pkg_short_errors_supported=no
+fi[]dnl
+])# _PKG_SHORT_ERRORS_SUPPORTED
+
+
+# PKG_CHECK_MODULES(VARIABLE-PREFIX, MODULES, [ACTION-IF-FOUND],
+# [ACTION-IF-NOT-FOUND])
+#
+#
+# Note that if there is a possibility the first call to
+# PKG_CHECK_MODULES might not happen, you should be sure to include an
+# explicit call to PKG_PROG_PKG_CONFIG in your configure.ac
+#
+#
+# --------------------------------------------------------------
+AC_DEFUN([PKG_CHECK_MODULES],
+[AC_REQUIRE([PKG_PROG_PKG_CONFIG])dnl
+AC_ARG_VAR([$1][_CFLAGS], [C compiler flags for $1, overriding pkg-config])dnl
+AC_ARG_VAR([$1][_LIBS], [linker flags for $1, overriding pkg-config])dnl
+
+pkg_failed=no
+AC_MSG_CHECKING([for $1])
+
+_PKG_CONFIG([$1][_CFLAGS], [cflags], [$2])
+_PKG_CONFIG([$1][_LIBS], [libs], [$2])
+
+m4_define([_PKG_TEXT], [Alternatively, you may set the environment variables $1[]_CFLAGS
+and $1[]_LIBS to avoid the need to call pkg-config.
+See the pkg-config man page for more details.])
+
+if test $pkg_failed = yes; then
+   	AC_MSG_RESULT([no])
+        _PKG_SHORT_ERRORS_SUPPORTED
+        if test $_pkg_short_errors_supported = yes; then
+	        $1[]_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors "$2" 2>&1`
+        else 
+	        $1[]_PKG_ERRORS=`$PKG_CONFIG --print-errors "$2" 2>&1`
+        fi
+	# Put the nasty error message in config.log where it belongs
+	echo "$$1[]_PKG_ERRORS" >&AS_MESSAGE_LOG_FD
+
+	m4_default([$4], [AC_MSG_ERROR(
+[Package requirements ($2) were not met:
+
+$$1_PKG_ERRORS
+
+Consider adjusting the PKG_CONFIG_PATH environment variable if you
+installed software in a non-standard prefix.
+
+_PKG_TEXT])
+        ])
+elif test $pkg_failed = untried; then
+     	AC_MSG_RESULT([no])
+	m4_default([$4], [AC_MSG_FAILURE(
+[The pkg-config script could not be found or is too old.  Make sure it
+is in your PATH or set the PKG_CONFIG environment variable to the full
+path to pkg-config.
+
+_PKG_TEXT
+
+To get pkg-config, see <http://pkg-config.freedesktop.org/>.])
+        ])
+else
+	$1[]_CFLAGS=$pkg_cv_[]$1[]_CFLAGS
+	$1[]_LIBS=$pkg_cv_[]$1[]_LIBS
+        AC_MSG_RESULT([yes])
+	$3
+fi[]dnl
+])# PKG_CHECK_MODULES
+

autoconf/install-sh

@@ -1,36 +1,62 @@
 #!/bin/sh
-#
 # install - install a program, script, or datafile
-# This comes from X11R5 (mit/util/scripts/install.sh).
+
+scriptversion=2006-10-14.15
+
+# This originates from X11R5 (mit/util/scripts/install.sh), which was
+# later released in X11R6 (xc/config/util/install.sh) with the
+# following copyright and license.
 #
-# Copyright 1991 by the Massachusetts Institute of Technology
+# Copyright (C) 1994 X Consortium
 #
-# Permission to use, copy, modify, distribute, and sell this software and its
-# documentation for any purpose is hereby granted without fee, provided that
-# the above copyright notice appear in all copies and that both that
-# copyright notice and this permission notice appear in supporting
-# documentation, and that the name of M.I.T. not be used in advertising or
-# publicity pertaining to distribution of the software without specific,
-# written prior permission.  M.I.T. makes no representations about the
-# suitability of this software for any purpose.  It is provided "as is"
-# without express or implied warranty.
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to
+# deal in the Software without restriction, including without limitation the
+# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+# sell copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+# X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+# AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNEC-
+# TION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+# Except as contained in this notice, the name of the X Consortium shall not
+# be used in advertising or otherwise to promote the sale, use or other deal-
+# ings in this Software without prior written authorization from the X Consor-
+# tium.
+#
+#
+# FSF changes to this file are in the public domain.
 #
 # Calling this script install-sh is preferred over install.sh, to prevent
 # `make' implicit rules from creating a file called install from it
 # when there is no Makefile.
 #
 # This script is compatible with the BSD install script, but was written
-# from scratch.  It can only install one file at a time, a restriction
-# shared with many OS's install programs.
+# from scratch.
 
+nl='
+'
+IFS=" ""	$nl"
 
 # set DOITPROG to echo to test this script
 
 # Don't use :- since 4.3BSD and earlier shells don't like it.
 doit="${DOITPROG-}"
+if test -z "$doit"; then
+  doit_exec=exec
+else
+  doit_exec=$doit
+fi
 
-
-# put in absolute paths if you don't have them in your path; or use env. vars.
+# Put in absolute file names if you don't have them in your path;
+# or use environment vars.
 
 mvprog="${MVPROG-mv}"
 cpprog="${CPPROG-cp}"
@@ -41,211 +67,441 @@ stripprog="${STRIPPROG-strip}"
 rmprog="${RMPROG-rm}"
 mkdirprog="${MKDIRPROG-mkdir}"
 
-transformbasename=""
-transform_arg=""
-instcmd="$mvprog"
-chmodcmd="$chmodprog 0755"
-chowncmd=""
-chgrpcmd=""
-stripcmd=""
+posix_glob=
+posix_mkdir=
+
+# Desired mode of installed file.
+mode=0755
+
+chmodcmd=$chmodprog
+chowncmd=
+chgrpcmd=
+stripcmd=
 rmcmd="$rmprog -f"
 mvcmd="$mvprog"
-src=""
-dst=""
-dir_arg=""
+src=
+dst=
+dir_arg=
+dstarg=
+no_target_directory=
 
-while [ x"$1" != x ]; do
-    case $1 in
-	-c) instcmd="$cpprog"
-	    shift
-	    continue;;
+usage="Usage: $0 [OPTION]... [-T] SRCFILE DSTFILE
+   or: $0 [OPTION]... SRCFILES... DIRECTORY
+   or: $0 [OPTION]... -t DIRECTORY SRCFILES...
+   or: $0 [OPTION]... -d DIRECTORIES...
 
-	-d) dir_arg=true
-	    shift
-	    continue;;
+In the 1st form, copy SRCFILE to DSTFILE.
+In the 2nd and 3rd, copy all SRCFILES to DIRECTORY.
+In the 4th, create DIRECTORIES.
 
-	-m) chmodcmd="$chmodprog $2"
-	    shift
-	    shift
-	    continue;;
+Options:
+-c         (ignored)
+-d         create directories instead of installing files.
+-g GROUP   $chgrpprog installed files to GROUP.
+-m MODE    $chmodprog installed files to MODE.
+-o USER    $chownprog installed files to USER.
+-s         $stripprog installed files.
+-t DIRECTORY  install into DIRECTORY.
+-T         report an error if DSTFILE is a directory.
+--help     display this help and exit.
+--version  display version info and exit.
 
-	-o) chowncmd="$chownprog $2"
-	    shift
-	    shift
-	    continue;;
+Environment variables override the default commands:
+  CHGRPPROG CHMODPROG CHOWNPROG CPPROG MKDIRPROG MVPROG RMPROG STRIPPROG
+"
 
-	-g) chgrpcmd="$chgrpprog $2"
-	    shift
-	    shift
-	    continue;;
+while test $# -ne 0; do
+  case $1 in
+    -c) shift
+        continue;;
 
-	-s) stripcmd="$stripprog"
-	    shift
-	    continue;;
+    -d) dir_arg=true
+        shift
+        continue;;
 
-	-t=*) transformarg=`echo $1 | sed 's/-t=//'`
-	    shift
-	    continue;;
+    -g) chgrpcmd="$chgrpprog $2"
+        shift
+        shift
+        continue;;
 
-	-b=*) transformbasename=`echo $1 | sed 's/-b=//'`
-	    shift
-	    continue;;
+    --help) echo "$usage"; exit $?;;
 
-	*)  if [ x"$src" = x ]
-	    then
-		src=$1
-	    else
-		# this colon is to work around a 386BSD /bin/sh bug
-		:
-		dst=$1
-	    fi
-	    shift
-	    continue;;
-    esac
-done
+    -m) mode=$2
+        shift
+        shift
+	case $mode in
+	  *' '* | *'	'* | *'
+'*	  | *'*'* | *'?'* | *'['*)
+	    echo "$0: invalid mode: $mode" >&2
+	    exit 1;;
+	esac
+        continue;;
 
-if [ x"$src" = x ]
-then
-	echo "install:	no input file specified"
-	exit 1
-else
-	true
-fi
+    -o) chowncmd="$chownprog $2"
+        shift
+        shift
+        continue;;
 
-if [ x"$dir_arg" != x ]; then
-	dst=$src
-	src=""
-	
-	if [ -d $dst ]; then
-		instcmd=:
-		chmodcmd=""
-	else
-		instcmd=mkdir
-	fi
-else
+    -s) stripcmd=$stripprog
+        shift
+        continue;;
 
-# Waiting for this to be detected by the "$instcmd $src $dsttmp" command
-# might cause directories to be created, which would be especially bad 
-# if $src (and thus $dsttmp) contains '*'.
-
-	if [ -f $src -o -d $src ]
-	then
-		true
-	else
-		echo "install:  $src does not exist"
-		exit 1
-	fi
-	
-	if [ x"$dst" = x ]
-	then
-		echo "install:	no destination specified"
-		exit 1
-	else
-		true
-	fi
-
-# If destination is a directory, append the input filename; if your system
-# does not like double slashes in filenames, you may need to add some logic
-
-	if [ -d $dst ]
-	then
-		dst="$dst"/`basename $src`
-	else
-		true
-	fi
-fi
-
-## this sed command emulates the dirname command
-dstdir=`echo $dst | sed -e 's,[^/]*$,,;s,/$,,;s,^$,.,'`
-
-# Make sure that the destination directory exists.
-#  this part is taken from Noah Friedman's mkinstalldirs script
-
-# Skip lots of stat calls in the usual case.
-if [ ! -d "$dstdir" ]; then
-defaultIFS='	
-'
-IFS="${IFS-${defaultIFS}}"
-
-oIFS="${IFS}"
-# Some sh's can't handle IFS=/ for some reason.
-IFS='%'
-set - `echo ${dstdir} | sed -e 's@/@%@g' -e 's@^%@/@'`
-IFS="${oIFS}"
-
-pathcomp=''
-
-while [ $# -ne 0 ] ; do
-	pathcomp="${pathcomp}${1}"
+    -t) dstarg=$2
 	shift
+	shift
+	continue;;
 
-	if [ ! -d "${pathcomp}" ] ;
-        then
-		$mkdirprog "${pathcomp}"
-	else
-		true
-	fi
+    -T) no_target_directory=true
+	shift
+	continue;;
 
-	pathcomp="${pathcomp}/"
+    --version) echo "$0 $scriptversion"; exit $?;;
+
+    --)	shift
+	break;;
+
+    -*)	echo "$0: invalid option: $1" >&2
+	exit 1;;
+
+    *)  break;;
+  esac
 done
+
+if test $# -ne 0 && test -z "$dir_arg$dstarg"; then
+  # When -d is used, all remaining arguments are directories to create.
+  # When -t is used, the destination is already specified.
+  # Otherwise, the last argument is the destination.  Remove it from $@.
+  for arg
+  do
+    if test -n "$dstarg"; then
+      # $@ is not empty: it contains at least $arg.
+      set fnord "$@" "$dstarg"
+      shift # fnord
+    fi
+    shift # arg
+    dstarg=$arg
+  done
 fi
 
-if [ x"$dir_arg" != x ]
-then
-	$doit $instcmd $dst &&
+if test $# -eq 0; then
+  if test -z "$dir_arg"; then
+    echo "$0: no input file specified." >&2
+    exit 1
+  fi
+  # It's OK to call `install-sh -d' without argument.
+  # This can happen when creating conditional directories.
+  exit 0
+fi
 
-	if [ x"$chowncmd" != x ]; then $doit $chowncmd $dst; else true ; fi &&
-	if [ x"$chgrpcmd" != x ]; then $doit $chgrpcmd $dst; else true ; fi &&
-	if [ x"$stripcmd" != x ]; then $doit $stripcmd $dst; else true ; fi &&
-	if [ x"$chmodcmd" != x ]; then $doit $chmodcmd $dst; else true ; fi
-else
+if test -z "$dir_arg"; then
+  trap '(exit $?); exit' 1 2 13 15
 
-# If we're going to rename the final executable, determine the name now.
+  # Set umask so as not to create temps with too-generous modes.
+  # However, 'strip' requires both read and write access to temps.
+  case $mode in
+    # Optimize common cases.
+    *644) cp_umask=133;;
+    *755) cp_umask=22;;
 
-	if [ x"$transformarg" = x ] 
-	then
-		dstfile=`basename $dst`
+    *[0-7])
+      if test -z "$stripcmd"; then
+	u_plus_rw=
+      else
+	u_plus_rw='% 200'
+      fi
+      cp_umask=`expr '(' 777 - $mode % 1000 ')' $u_plus_rw`;;
+    *)
+      if test -z "$stripcmd"; then
+	u_plus_rw=
+      else
+	u_plus_rw=,u+rw
+      fi
+      cp_umask=$mode$u_plus_rw;;
+  esac
+fi
+
+for src
+do
+  # Protect names starting with `-'.
+  case $src in
+    -*) src=./$src ;;
+  esac
+
+  if test -n "$dir_arg"; then
+    dst=$src
+    dstdir=$dst
+    test -d "$dstdir"
+    dstdir_status=$?
+  else
+
+    # Waiting for this to be detected by the "$cpprog $src $dsttmp" command
+    # might cause directories to be created, which would be especially bad
+    # if $src (and thus $dsttmp) contains '*'.
+    if test ! -f "$src" && test ! -d "$src"; then
+      echo "$0: $src does not exist." >&2
+      exit 1
+    fi
+
+    if test -z "$dstarg"; then
+      echo "$0: no destination specified." >&2
+      exit 1
+    fi
+
+    dst=$dstarg
+    # Protect names starting with `-'.
+    case $dst in
+      -*) dst=./$dst ;;
+    esac
+
+    # If destination is a directory, append the input filename; won't work
+    # if double slashes aren't ignored.
+    if test -d "$dst"; then
+      if test -n "$no_target_directory"; then
+	echo "$0: $dstarg: Is a directory" >&2
+	exit 1
+      fi
+      dstdir=$dst
+      dst=$dstdir/`basename "$src"`
+      dstdir_status=0
+    else
+      # Prefer dirname, but fall back on a substitute if dirname fails.
+      dstdir=`
+	(dirname "$dst") 2>/dev/null ||
+	expr X"$dst" : 'X\(.*[^/]\)//*[^/][^/]*/*$' \| \
+	     X"$dst" : 'X\(//\)[^/]' \| \
+	     X"$dst" : 'X\(//\)$' \| \
+	     X"$dst" : 'X\(/\)' \| . 2>/dev/null ||
+	echo X"$dst" |
+	    sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
+		   s//\1/
+		   q
+		 }
+		 /^X\(\/\/\)[^/].*/{
+		   s//\1/
+		   q
+		 }
+		 /^X\(\/\/\)$/{
+		   s//\1/
+		   q
+		 }
+		 /^X\(\/\).*/{
+		   s//\1/
+		   q
+		 }
+		 s/.*/./; q'
+      `
+
+      test -d "$dstdir"
+      dstdir_status=$?
+    fi
+  fi
+
+  obsolete_mkdir_used=false
+
+  if test $dstdir_status != 0; then
+    case $posix_mkdir in
+      '')
+	# Create intermediate dirs using mode 755 as modified by the umask.
+	# This is like FreeBSD 'install' as of 1997-10-28.
+	umask=`umask`
+	case $stripcmd.$umask in
+	  # Optimize common cases.
+	  *[2367][2367]) mkdir_umask=$umask;;
+	  .*0[02][02] | .[02][02] | .[02]) mkdir_umask=22;;
+
+	  *[0-7])
+	    mkdir_umask=`expr $umask + 22 \
+	      - $umask % 100 % 40 + $umask % 20 \
+	      - $umask % 10 % 4 + $umask % 2
+	    `;;
+	  *) mkdir_umask=$umask,go-w;;
+	esac
+
+	# With -d, create the new directory with the user-specified mode.
+	# Otherwise, rely on $mkdir_umask.
+	if test -n "$dir_arg"; then
+	  mkdir_mode=-m$mode
 	else
-		dstfile=`basename $dst $transformbasename | 
-			sed $transformarg`$transformbasename
+	  mkdir_mode=
 	fi
 
-# don't allow the sed command to completely eliminate the filename
+	posix_mkdir=false
+	case $umask in
+	  *[123567][0-7][0-7])
+	    # POSIX mkdir -p sets u+wx bits regardless of umask, which
+	    # is incompatible with FreeBSD 'install' when (umask & 300) != 0.
+	    ;;
+	  *)
+	    tmpdir=${TMPDIR-/tmp}/ins$RANDOM-$$
+	    trap 'ret=$?; rmdir "$tmpdir/d" "$tmpdir" 2>/dev/null; exit $ret' 0
 
-	if [ x"$dstfile" = x ] 
-	then
-		dstfile=`basename $dst`
+	    if (umask $mkdir_umask &&
+		exec $mkdirprog $mkdir_mode -p -- "$tmpdir/d") >/dev/null 2>&1
+	    then
+	      if test -z "$dir_arg" || {
+		   # Check for POSIX incompatibilities with -m.
+		   # HP-UX 11.23 and IRIX 6.5 mkdir -m -p sets group- or
+		   # other-writeable bit of parent directory when it shouldn't.
+		   # FreeBSD 6.1 mkdir -m -p sets mode of existing directory.
+		   ls_ld_tmpdir=`ls -ld "$tmpdir"`
+		   case $ls_ld_tmpdir in
+		     d????-?r-*) different_mode=700;;
+		     d????-?--*) different_mode=755;;
+		     *) false;;
+		   esac &&
+		   $mkdirprog -m$different_mode -p -- "$tmpdir" && {
+		     ls_ld_tmpdir_1=`ls -ld "$tmpdir"`
+		     test "$ls_ld_tmpdir" = "$ls_ld_tmpdir_1"
+		   }
+		 }
+	      then posix_mkdir=:
+	      fi
+	      rmdir "$tmpdir/d" "$tmpdir"
+	    else
+	      # Remove any dirs left behind by ancient mkdir implementations.
+	      rmdir ./$mkdir_mode ./-p ./-- 2>/dev/null
+	    fi
+	    trap '' 0;;
+	esac;;
+    esac
+
+    if
+      $posix_mkdir && (
+	umask $mkdir_umask &&
+	$doit_exec $mkdirprog $mkdir_mode -p -- "$dstdir"
+      )
+    then :
+    else
+
+      # The umask is ridiculous, or mkdir does not conform to POSIX,
+      # or it failed possibly due to a race condition.  Create the
+      # directory the slow way, step by step, checking for races as we go.
+
+      case $dstdir in
+	/*) prefix=/ ;;
+	-*) prefix=./ ;;
+	*)  prefix= ;;
+      esac
+
+      case $posix_glob in
+        '')
+	  if (set -f) 2>/dev/null; then
+	    posix_glob=true
+	  else
+	    posix_glob=false
+	  fi ;;
+      esac
+
+      oIFS=$IFS
+      IFS=/
+      $posix_glob && set -f
+      set fnord $dstdir
+      shift
+      $posix_glob && set +f
+      IFS=$oIFS
+
+      prefixes=
+
+      for d
+      do
+	test -z "$d" && continue
+
+	prefix=$prefix$d
+	if test -d "$prefix"; then
+	  prefixes=
 	else
-		true
+	  if $posix_mkdir; then
+	    (umask=$mkdir_umask &&
+	     $doit_exec $mkdirprog $mkdir_mode -p -- "$dstdir") && break
+	    # Don't fail if two instances are running concurrently.
+	    test -d "$prefix" || exit 1
+	  else
+	    case $prefix in
+	      *\'*) qprefix=`echo "$prefix" | sed "s/'/'\\\\\\\\''/g"`;;
+	      *) qprefix=$prefix;;
+	    esac
+	    prefixes="$prefixes '$qprefix'"
+	  fi
 	fi
+	prefix=$prefix/
+      done
 
-# Make a temp file name in the proper directory.
+      if test -n "$prefixes"; then
+	# Don't fail if two instances are running concurrently.
+	(umask $mkdir_umask &&
+	 eval "\$doit_exec \$mkdirprog $prefixes") ||
+	  test -d "$dstdir" || exit 1
+	obsolete_mkdir_used=true
+      fi
+    fi
+  fi
 
-	dsttmp=$dstdir/#inst.$$#
+  if test -n "$dir_arg"; then
+    { test -z "$chowncmd" || $doit $chowncmd "$dst"; } &&
+    { test -z "$chgrpcmd" || $doit $chgrpcmd "$dst"; } &&
+    { test "$obsolete_mkdir_used$chowncmd$chgrpcmd" = false ||
+      test -z "$chmodcmd" || $doit $chmodcmd $mode "$dst"; } || exit 1
+  else
 
-# Move or copy the file name to the temp name
+    # Make a couple of temp file names in the proper directory.
+    dsttmp=$dstdir/_inst.$$_
+    rmtmp=$dstdir/_rm.$$_
 
-	$doit $instcmd $src $dsttmp &&
+    # Trap to clean up those temp files at exit.
+    trap 'ret=$?; rm -f "$dsttmp" "$rmtmp" && exit $ret' 0
 
-	trap "rm -f ${dsttmp}" 0 &&
+    # Copy the file name to the temp name.
+    (umask $cp_umask && $doit_exec $cpprog "$src" "$dsttmp") &&
 
-# and set any options; do chmod last to preserve setuid bits
+    # and set any options; do chmod last to preserve setuid bits.
+    #
+    # If any of these fail, we abort the whole thing.  If we want to
+    # ignore errors from any of these, just make sure not to ignore
+    # errors from the above "$doit $cpprog $src $dsttmp" command.
+    #
+    { test -z "$chowncmd" || $doit $chowncmd "$dsttmp"; } \
+      && { test -z "$chgrpcmd" || $doit $chgrpcmd "$dsttmp"; } \
+      && { test -z "$stripcmd" || $doit $stripcmd "$dsttmp"; } \
+      && { test -z "$chmodcmd" || $doit $chmodcmd $mode "$dsttmp"; } &&
 
-# If any of these fail, we abort the whole thing.  If we want to
-# ignore errors from any of these, just make sure not to ignore
-# errors from the above "$doit $instcmd $src $dsttmp" command.
+    # Now rename the file to the real destination.
+    { $doit $mvcmd -f "$dsttmp" "$dst" 2>/dev/null \
+      || {
+	   # The rename failed, perhaps because mv can't rename something else
+	   # to itself, or perhaps because mv is so ancient that it does not
+	   # support -f.
 
-	if [ x"$chowncmd" != x ]; then $doit $chowncmd $dsttmp; else true;fi &&
-	if [ x"$chgrpcmd" != x ]; then $doit $chgrpcmd $dsttmp; else true;fi &&
-	if [ x"$stripcmd" != x ]; then $doit $stripcmd $dsttmp; else true;fi &&
-	if [ x"$chmodcmd" != x ]; then $doit $chmodcmd $dsttmp; else true;fi &&
+	   # Now remove or move aside any old file at destination location.
+	   # We try this two ways since rm can't unlink itself on some
+	   # systems and the destination file might be busy for other
+	   # reasons.  In this case, the final cleanup might fail but the new
+	   # file should still install successfully.
+	   {
+	     if test -f "$dst"; then
+	       $doit $rmcmd -f "$dst" 2>/dev/null \
+	       || { $doit $mvcmd -f "$dst" "$rmtmp" 2>/dev/null \
+		     && { $doit $rmcmd -f "$rmtmp" 2>/dev/null; :; }; }\
+	       || {
+		 echo "$0: cannot unlink or rename $dst" >&2
+		 (exit 1); exit 1
+	       }
+	     else
+	       :
+	     fi
+	   } &&
 
-# Now rename the file to the real destination.
+	   # Now rename the file to the real destination.
+	   $doit $mvcmd "$dsttmp" "$dst"
+	 }
+    } || exit 1
 
-	$doit $rmcmd -f $dstdir/$dstfile &&
-	$doit $mvcmd $dsttmp $dstdir/$dstfile 
+    trap '' 0
+  fi
+done
 
-fi &&
-
-
-exit 0
+# Local variables:
+# eval: (add-hook 'write-file-hooks 'time-stamp)
+# time-stamp-start: "scriptversion="
+# time-stamp-format: "%:y-%02m-%02d.%02H"
+# time-stamp-end: "$"
+# End:

daemons/Makefile.in

@@ -0,0 +1,52 @@
+#
+# Copyright (C) 2004-2011 Red Hat, Inc. All rights reserved.
+#
+# This file is part of LVM2.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU General Public License v.2.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+ifeq ("@BUILD_LVMETAD@", "yes")
+  SUBDIRS += common lvmetad
+endif
+
+.PHONY: dmeventd clvmd common cmirrord lvmetad
+
+ifneq ("@CLVMD@", "none")
+  SUBDIRS += clvmd
+endif
+
+ifeq ("@BUILD_CMIRRORD@", "yes")
+  SUBDIRS += cmirrord
+endif
+
+ifeq ("@BUILD_DMEVENTD@", "yes")
+  SUBDIRS += dmeventd
+ifneq ("$(CFLOW_CMD)", "")
+daemons.cflow: dmeventd.cflow
+endif
+endif
+
+ifeq ($(MAKECMDGOALS),distclean)
+  SUBDIRS = clvmd cmirrord common dmeventd lvmetad
+endif
+
+include $(top_builddir)/make.tmpl
+
+ifeq ("@BUILD_DMEVENTD@", "yes")
+device-mapper: dmeventd.device-mapper
+endif
+
+ifeq ("@BUILD_LVMETAD@", "yes")
+lvmetad: common.device-mapper
+endif
+

daemons/clvmd/Makefile.in

@@ -0,0 +1,107 @@
+#
+# Copyright (C) 2004 Red Hat, Inc. All rights reserved.
+#
+# This file is part of LVM2.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU General Public License v.2.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+CMAN_LIBS = @CMAN_LIBS@
+CMAN_CFLAGS = @CMAN_CFLAGS@
+CMAP_LIBS = @CMAP_LIBS@
+CMAP_CFLAGS = @CMAP_CFLAGS@
+CONFDB_LIBS = @CONFDB_LIBS@
+CONFDB_CFLAGS = @CONFDB_CFLAGS@
+CPG_LIBS = @CPG_LIBS@
+CPG_CFLAGS = @CPG_CFLAGS@
+DLM_LIBS = @DLM_LIBS@
+DLM_CFLAGS = @DLM_CFLAGS@
+QUORUM_LIBS = @QUORUM_LIBS@
+QUORUM_CFLAGS = @QUORUM_CFLAGS@
+SALCK_LIBS = @SALCK_LIBS@
+SALCK_CFLAGS = @SALCK_CFLAGS@
+
+SOURCES = \
+	clvmd-command.c  \
+	clvmd.c          \
+	lvm-functions.c  \
+	refresh_clvmd.c
+
+ifeq ("@DEBUG@", "yes")
+	DEFS += -DDEBUG
+endif
+
+ifneq (,$(findstring cman,, "@CLVMD@,"))
+	SOURCES += clvmd-cman.c
+	LMLIBS += $(CMAN_LIBS) $(CONFDB_LIBS) $(DLM_LIBS)
+	CFLAGS += $(CMAN_CFLAGS) $(CONFDB_CFLAGS) $(DLM_CFLAGS)
+	DEFS += -DUSE_CMAN
+endif
+
+ifneq (,$(findstring openais,, "@CLVMD@,"))
+	SOURCES += clvmd-openais.c
+	LMLIBS += $(CONFDB_LIBS) $(CPG_LIBS) $(SALCK_LIBS)
+	CFLAGS += $(CONFDB_CFLAGS) $(CPG_CFLAGS) $(SALCK_CFLAGS)
+	DEFS += -DUSE_OPENAIS
+endif
+
+ifneq (,$(findstring corosync,, "@CLVMD@,"))
+	SOURCES += clvmd-corosync.c
+	LMLIBS += $(CMAP_LIBS) $(CONFDB_LIBS) $(CPG_LIBS) $(DLM_LIBS) $(QUORUM_LIBS)
+	CFLAGS += $(CMAP_CFLAGS) $(CONFDB_CFLAGS) $(CPG_CFLAGS) $(DLM_CFLAGS) $(QUORUM_CFLAGS)
+	DEFS += -DUSE_COROSYNC
+endif
+
+ifneq (,$(findstring singlenode,, "@CLVMD@,"))
+	SOURCES += clvmd-singlenode.c
+	DEFS += -DUSE_SINGLENODE
+endif
+
+ifeq ($(MAKECMDGOALS),distclean)
+	SOURCES += clvmd-cman.c
+	SOURCES += clvmd-openais.c
+	SOURCES += clvmd-corosync.c
+	SOURCES += clvmd-singlenode.c
+endif
+
+TARGETS = \
+	clvmd
+
+LVMLIBS = $(LVMINTERNAL_LIBS)
+
+ifeq ("@DMEVENTD@", "yes")
+	LVMLIBS += -ldevmapper-event
+endif
+ 
+include $(top_builddir)/make.tmpl
+
+LVMLIBS += -ldevmapper
+LIBS += $(PTHREAD_LIBS)
+
+DEFS += -D_REENTRANT
+CFLAGS += -fno-strict-aliasing
+
+INSTALL_TARGETS = \
+	install_clvmd
+
+clvmd: $(OBJECTS) $(top_builddir)/lib/liblvm-internal.a
+	$(CC) $(CFLAGS) $(LDFLAGS) -o clvmd $(OBJECTS) \
+		$(LVMLIBS) $(LMLIBS) $(LIBS)
+
+.PHONY: install_clvmd
+
+install_clvmd: $(TARGETS)
+	$(INSTALL_PROGRAM) -D clvmd $(usrsbindir)/clvmd
+
+install: $(INSTALL_TARGETS)
+
+install_cluster: $(INSTALL_TARGETS)

daemons/clvmd/clvm.h

@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) 2002-2004 Sistina Software, Inc. All rights reserved.
+ * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/* Definitions for CLVMD server and clients */
+
+/*
+ * The protocol spoken over the cluster and across the local socket.
+ */
+
+#ifndef _CLVM_H
+#define _CLVM_H
+
+#include "configure.h"
+
+struct clvm_header {
+	uint8_t  cmd;	        /* See below */
+	uint8_t  flags;	        /* See below */
+	uint16_t xid;	        /* Transaction ID */
+	uint32_t clientid;	/* Only used in Daemon->Daemon comms */
+	int32_t  status;	/* For replies, whether request succeeded */
+	uint32_t arglen;	/* Length of argument below. 
+				   If >1500 then it will be passed 
+				   around the cluster in the system LV */
+	char node[1];		/* Actually a NUL-terminated string, node name.
+				   If this is empty then the command is 
+				   forwarded to all cluster nodes unless 
+				   FLAG_LOCAL or FLAG_REMOTE is also set. */
+	char args[1];		/* Arguments for the command follow the 
+				   node name, This member is only
+				   valid if the node name is empty */
+} __attribute__ ((packed));
+
+/* Flags */
+#define CLVMD_FLAG_LOCAL	1	/* Only do this on the local node */
+#define CLVMD_FLAG_SYSTEMLV	2	/* Data in system LV under my node name */
+#define CLVMD_FLAG_NODEERRS	4	/* Reply has errors in node-specific portion */
+#define CLVMD_FLAG_REMOTE	8	/* Do this on all nodes except for the local node */
+
+/* Name of the local socket to communicate between lvm and clvmd */
+static const char CLVMD_SOCKNAME[]= DEFAULT_RUN_DIR "/clvmd.sock";
+
+/* Internal commands & replies */
+#define CLVMD_CMD_REPLY    1
+#define CLVMD_CMD_VERSION  2	/* Send version around cluster when we start */
+#define CLVMD_CMD_GOAWAY   3	/* Die if received this - we are running 
+				   an incompatible version */
+#define CLVMD_CMD_TEST     4	/* Just for mucking about */
+
+#define CLVMD_CMD_LOCK              30
+#define CLVMD_CMD_UNLOCK            31
+
+/* Lock/Unlock commands */
+#define CLVMD_CMD_LOCK_LV           50
+#define CLVMD_CMD_LOCK_VG           51
+#define CLVMD_CMD_LOCK_QUERY	    52
+
+/* Misc functions */
+#define CLVMD_CMD_REFRESH	    40
+#define CLVMD_CMD_GET_CLUSTERNAME   41
+#define CLVMD_CMD_SET_DEBUG	    42
+#define CLVMD_CMD_VG_BACKUP	    43
+#define CLVMD_CMD_RESTART	    44
+#define CLVMD_CMD_SYNC_NAMES	    45
+
+/* Used internally by some callers, but not part of the protocol.*/
+#define NODE_ALL	"*"
+#define NODE_LOCAL	"."
+#define NODE_REMOTE	"^"
+
+#endif

daemons/clvmd/clvmd-cman.c

@@ -0,0 +1,506 @@
+/*
+ * Copyright (C) 2002-2004 Sistina Software, Inc. All rights reserved.
+ * Copyright (C) 2004 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/*
+ * CMAN communication layer for clvmd.
+ */
+
+#include "clvmd-common.h"
+
+#include <pthread.h>
+
+#include "clvmd-comms.h"
+#include "clvm.h"
+#include "clvmd.h"
+#include "lvm-functions.h"
+
+#include <libdlm.h>
+
+#include <syslog.h>
+
+#define LOCKSPACE_NAME "clvmd"
+
+struct clvmd_node
+{
+	struct cman_node *node;
+	int clvmd_up;
+};
+
+static int num_nodes;
+static struct cman_node *nodes = NULL;
+static struct cman_node this_node;
+static int count_nodes; /* size of allocated nodes array */
+static struct dm_hash_table *node_updown_hash;
+static dlm_lshandle_t *lockspace;
+static cman_handle_t c_handle;
+
+static void count_clvmds_running(void);
+static void get_members(void);
+static int nodeid_from_csid(const char *csid);
+static int name_from_nodeid(int nodeid, char *name);
+static void event_callback(cman_handle_t handle, void *private, int reason, int arg);
+static void data_callback(cman_handle_t handle, void *private,
+			  char *buf, int len, uint8_t port, int nodeid);
+
+struct lock_wait {
+	pthread_cond_t cond;
+	pthread_mutex_t mutex;
+	struct dlm_lksb lksb;
+};
+
+static int _init_cluster(void)
+{
+	node_updown_hash = dm_hash_create(100);
+
+	/* Open the cluster communication socket */
+	c_handle = cman_init(NULL);
+	if (!c_handle) {
+		syslog(LOG_ERR, "Can't open cluster manager socket: %m");
+		return -1;
+	}
+	DEBUGLOG("Connected to CMAN\n");
+
+	if (cman_start_recv_data(c_handle, data_callback, CLUSTER_PORT_CLVMD)) {
+		syslog(LOG_ERR, "Can't bind cluster socket: %m");
+		return -1;
+	}
+
+	if (cman_start_notification(c_handle, event_callback)) {
+		syslog(LOG_ERR, "Can't start cluster event listening");
+		return -1;
+	}
+
+	/* Get the cluster members list */
+	get_members();
+	count_clvmds_running();
+
+	DEBUGLOG("CMAN initialisation complete\n");
+
+	/* Create a lockspace for LV & VG locks to live in */
+	lockspace = dlm_open_lockspace(LOCKSPACE_NAME);
+	if (!lockspace) {
+		lockspace = dlm_create_lockspace(LOCKSPACE_NAME, 0600);
+		if (!lockspace) {
+			syslog(LOG_ERR, "Unable to create DLM lockspace for CLVM: %m");
+			return -1;
+		}
+		DEBUGLOG("Created DLM lockspace for CLVMD.\n");
+	} else
+		DEBUGLOG("Opened existing DLM lockspace for CLVMD.\n");
+
+	dlm_ls_pthread_init(lockspace);
+	DEBUGLOG("DLM initialisation complete\n");
+	return 0;
+}
+
+static void _cluster_init_completed(void)
+{
+	clvmd_cluster_init_completed();
+}
+
+static int _get_main_cluster_fd()
+{
+	return cman_get_fd(c_handle);
+}
+
+static int _get_num_nodes()
+{
+	int i;
+	int nnodes = 0;
+
+	/* return number of ACTIVE nodes */
+	for (i=0; i<num_nodes; i++) {
+		if (nodes[i].cn_member && nodes[i].cn_nodeid)
+			nnodes++;
+	}
+	return nnodes;
+}
+
+/* send_message with the fd check removed */
+static int _cluster_send_message(const void *buf, int msglen, const char *csid,
+				 const char *errtext)
+{
+	int nodeid = 0;
+
+	if (csid)
+		memcpy(&nodeid, csid, CMAN_MAX_CSID_LEN);
+
+	if (cman_send_data(c_handle, buf, msglen, 0, CLUSTER_PORT_CLVMD, nodeid) <= 0)
+	{
+		log_error("%s", errtext);
+	}
+	return msglen;
+}
+
+static void _get_our_csid(char *csid)
+{
+	if (this_node.cn_nodeid == 0) {
+		cman_get_node(c_handle, 0, &this_node);
+	}
+	memcpy(csid, &this_node.cn_nodeid, CMAN_MAX_CSID_LEN);
+}
+
+/* Call a callback routine for each node is that known (down means not running a clvmd) */
+static int _cluster_do_node_callback(struct local_client *client,
+				     void (*callback) (struct local_client *,
+						       const char *,
+						       int))
+{
+	int i;
+	int somedown = 0;
+
+	for (i = 0; i < _get_num_nodes(); i++) {
+		if (nodes[i].cn_member && nodes[i].cn_nodeid) {
+			int up = (int)(long)dm_hash_lookup_binary(node_updown_hash, (char *)&nodes[i].cn_nodeid, sizeof(int));
+
+			callback(client, (char *)&nodes[i].cn_nodeid, up);
+			if (!up)
+				somedown = -1;
+		}
+	}
+	return somedown;
+}
+
+/* Process OOB messages from the cluster socket */
+static void event_callback(cman_handle_t handle, void *private, int reason, int arg)
+{
+	char namebuf[MAX_CLUSTER_MEMBER_NAME_LEN];
+
+	switch (reason) {
+        case CMAN_REASON_PORTCLOSED:
+		name_from_nodeid(arg, namebuf);
+		log_notice("clvmd on node %s has died\n", namebuf);
+		DEBUGLOG("Got port closed message, removing node %s\n", namebuf);
+
+		dm_hash_insert_binary(node_updown_hash, (char *)&arg, sizeof(int), (void *)0);
+		break;
+
+	case CMAN_REASON_STATECHANGE:
+		DEBUGLOG("Got state change message, re-reading members list\n");
+		get_members();
+		break;
+
+#if defined(LIBCMAN_VERSION) && LIBCMAN_VERSION >= 2
+	case CMAN_REASON_PORTOPENED:
+		/* Ignore this, wait for startup message from clvmd itself */
+		break;
+
+	case CMAN_REASON_TRY_SHUTDOWN:
+		DEBUGLOG("Got try shutdown, sending OK\n");
+		cman_replyto_shutdown(c_handle, 1);
+		break;
+#endif
+	default:
+		/* ERROR */
+		DEBUGLOG("Got unknown event callback message: %d\n", reason);
+		break;
+	}
+}
+
+static struct local_client *cman_client;
+static int _cluster_fd_callback(struct local_client *fd, char *buf, int len,
+				const char *csid,
+				struct local_client **new_client)
+{
+
+	/* Save this for data_callback */
+	cman_client = fd;
+
+	/* We never return a new client */
+	*new_client = NULL;
+
+	return cman_dispatch(c_handle, 0);
+}
+
+
+static void data_callback(cman_handle_t handle, void *private,
+			  char *buf, int len, uint8_t port, int nodeid)
+{
+	/* Ignore looped back messages */
+	if (nodeid == this_node.cn_nodeid)
+		return;
+	process_message(cman_client, buf, len, (char *)&nodeid);
+}
+
+static void _add_up_node(const char *csid)
+{
+	/* It's up ! */
+	int nodeid = nodeid_from_csid(csid);
+
+	dm_hash_insert_binary(node_updown_hash, (char *)&nodeid, sizeof(int), (void *)1);
+	DEBUGLOG("Added new node %d to updown list\n", nodeid);
+}
+
+static void _cluster_closedown()
+{
+	destroy_lvhash();
+	dlm_release_lockspace(LOCKSPACE_NAME, lockspace, 1);
+	cman_finish(c_handle);
+}
+
+static int is_listening(int nodeid)
+{
+	int status;
+
+	do {
+		status = cman_is_listening(c_handle, nodeid, CLUSTER_PORT_CLVMD);
+		if (status < 0 && errno == EBUSY) {	/* Don't busywait */
+			sleep(1);
+			errno = EBUSY;	/* In case sleep trashes it */
+		}
+	}
+	while (status < 0 && errno == EBUSY);
+
+	return status;
+}
+
+/* Populate the list of CLVMDs running.
+   called only at startup time */
+static void count_clvmds_running(void)
+{
+	int i;
+
+	for (i = 0; i < num_nodes; i++) {
+		int nodeid = nodes[i].cn_nodeid;
+
+		if (is_listening(nodeid) == 1)
+			dm_hash_insert_binary(node_updown_hash, (void *)&nodeid, sizeof(int), (void*)1);
+		else
+			dm_hash_insert_binary(node_updown_hash, (void *)&nodeid, sizeof(int), (void*)0);
+	}
+}
+
+/* Get a list of active cluster members */
+static void get_members()
+{
+	int retnodes;
+	int status;
+	int i;
+	int high_nodeid = 0;
+
+	num_nodes = cman_get_node_count(c_handle);
+	if (num_nodes == -1) {
+		log_error("Unable to get node count");
+		return;
+	}
+
+	/* Not enough room for new nodes list ? */
+	if (num_nodes > count_nodes && nodes) {
+		free(nodes);
+		nodes = NULL;
+	}
+
+	if (nodes == NULL) {
+		count_nodes = num_nodes + 10; /* Overallocate a little */
+		nodes = malloc(count_nodes * sizeof(struct cman_node));
+		if (!nodes) {
+			log_error("Unable to allocate nodes array\n");
+			exit(5);
+		}
+	}
+
+	status = cman_get_nodes(c_handle, count_nodes, &retnodes, nodes);
+	if (status < 0) {
+		log_error("Unable to get node details");
+		exit(6);
+	}
+
+	/* Get the highest nodeid */
+	for (i=0; i<retnodes; i++) {
+		if (nodes[i].cn_nodeid > high_nodeid)
+			high_nodeid = nodes[i].cn_nodeid;
+	}
+}
+
+
+/* Convert a node name to a CSID */
+static int _csid_from_name(char *csid, const char *name)
+{
+	int i;
+
+	for (i = 0; i < num_nodes; i++) {
+		if (strcmp(name, nodes[i].cn_name) == 0) {
+			memcpy(csid, &nodes[i].cn_nodeid, CMAN_MAX_CSID_LEN);
+			return 0;
+		}
+	}
+	return -1;
+}
+
+/* Convert a CSID to a node name */
+static int _name_from_csid(const char *csid, char *name)
+{
+	int i;
+
+	for (i = 0; i < num_nodes; i++) {
+		if (memcmp(csid, &nodes[i].cn_nodeid, CMAN_MAX_CSID_LEN) == 0) {
+			strcpy(name, nodes[i].cn_name);
+			return 0;
+		}
+	}
+	/* Who?? */
+	strcpy(name, "Unknown");
+	return -1;
+}
+
+/* Convert a node ID to a node name */
+static int name_from_nodeid(int nodeid, char *name)
+{
+	int i;
+
+	for (i = 0; i < num_nodes; i++) {
+		if (nodeid == nodes[i].cn_nodeid) {
+			strcpy(name, nodes[i].cn_name);
+			return 0;
+		}
+	}
+	/* Who?? */
+	strcpy(name, "Unknown");
+	return -1;
+}
+
+/* Convert a CSID to a node ID */
+static int nodeid_from_csid(const char *csid)
+{
+        int nodeid;
+
+	memcpy(&nodeid, csid, CMAN_MAX_CSID_LEN);
+
+	return nodeid;
+}
+
+static int _is_quorate()
+{
+	return cman_is_quorate(c_handle);
+}
+
+static void sync_ast_routine(void *arg)
+{
+	struct lock_wait *lwait = arg;
+
+	pthread_mutex_lock(&lwait->mutex);
+	pthread_cond_signal(&lwait->cond);
+	pthread_mutex_unlock(&lwait->mutex);
+}
+
+static int _sync_lock(const char *resource, int mode, int flags, int *lockid)
+{
+	int status;
+	struct lock_wait lwait;
+
+	if (!lockid) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	DEBUGLOG("sync_lock: '%s' mode:%d flags=%d\n", resource,mode,flags);
+	/* Conversions need the lockid in the LKSB */
+	if (flags & LKF_CONVERT)
+		lwait.lksb.sb_lkid = *lockid;
+
+	pthread_cond_init(&lwait.cond, NULL);
+	pthread_mutex_init(&lwait.mutex, NULL);
+	pthread_mutex_lock(&lwait.mutex);
+
+	status = dlm_ls_lock(lockspace,
+			     mode,
+			     &lwait.lksb,
+			     flags,
+			     resource,
+			     strlen(resource),
+			     0, sync_ast_routine, &lwait, NULL, NULL);
+	if (status)
+		return status;
+
+	/* Wait for it to complete */
+	pthread_cond_wait(&lwait.cond, &lwait.mutex);
+	pthread_mutex_unlock(&lwait.mutex);
+
+	*lockid = lwait.lksb.sb_lkid;
+
+	errno = lwait.lksb.sb_status;
+	DEBUGLOG("sync_lock: returning lkid %x\n", *lockid);
+	if (lwait.lksb.sb_status)
+		return -1;
+	else
+		return 0;
+}
+
+static int _sync_unlock(const char *resource /* UNUSED */, int lockid)
+{
+	int status;
+	struct lock_wait lwait;
+
+	DEBUGLOG("sync_unlock: '%s' lkid:%x\n", resource, lockid);
+
+	pthread_cond_init(&lwait.cond, NULL);
+	pthread_mutex_init(&lwait.mutex, NULL);
+	pthread_mutex_lock(&lwait.mutex);
+
+	status = dlm_ls_unlock(lockspace, lockid, 0, &lwait.lksb, &lwait);
+
+	if (status)
+		return status;
+
+	/* Wait for it to complete */
+	pthread_cond_wait(&lwait.cond, &lwait.mutex);
+	pthread_mutex_unlock(&lwait.mutex);
+
+	errno = lwait.lksb.sb_status;
+	if (lwait.lksb.sb_status != EUNLOCK)
+		return -1;
+	else
+		return 0;
+
+}
+
+static int _get_cluster_name(char *buf, int buflen)
+{
+	cman_cluster_t cluster_info;
+	int status;
+
+	status = cman_get_cluster(c_handle, &cluster_info);
+	if (!status) {
+		strncpy(buf, cluster_info.ci_name, buflen);
+	}
+	return status;
+}
+
+static struct cluster_ops _cluster_cman_ops = {
+	.name                     = "cman",
+	.cluster_init_completed   = _cluster_init_completed,
+	.cluster_send_message     = _cluster_send_message,
+	.name_from_csid           = _name_from_csid,
+	.csid_from_name           = _csid_from_name,
+	.get_num_nodes            = _get_num_nodes,
+	.cluster_fd_callback      = _cluster_fd_callback,
+	.get_main_cluster_fd      = _get_main_cluster_fd,
+	.cluster_do_node_callback = _cluster_do_node_callback,
+	.is_quorate               = _is_quorate,
+	.get_our_csid             = _get_our_csid,
+	.add_up_node              = _add_up_node,
+	.cluster_closedown        = _cluster_closedown,
+	.get_cluster_name         = _get_cluster_name,
+	.sync_lock                = _sync_lock,
+	.sync_unlock              = _sync_unlock,
+};
+
+struct cluster_ops *init_cman_cluster(void)
+{
+	if (!_init_cluster())
+		return &_cluster_cman_ops;
+	else
+		return NULL;
+}

daemons/clvmd/clvmd-command.c

@@ -0,0 +1,431 @@
+/*
+ * Copyright (C) 2002-2004 Sistina Software, Inc. All rights reserved.
+ * Copyright (C) 2004-2011 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/*
+
+  CLVMD Cluster LVM daemon command processor.
+
+  To add commands to the daemon simply add a processor in do_command and return
+  and messages back in buf and the length in *retlen. The initial value of
+  buflen is the maximum size of the buffer. if buf is not large enough then it
+  may be reallocated by the functions in here to a suitable size bearing in
+  mind that anything larger than the passed-in size will have to be returned
+  using the system LV and so performance will suffer.
+
+  The status return will be negated and passed back to the originating node.
+
+  pre- and post- command routines are called only on the local node. The
+  purpose is primarily to get and release locks, though the pre- routine should
+  also do any other local setups required by the command (if any) and can
+  return a failure code that prevents the command from being distributed around
+  the cluster
+
+  The pre- and post- routines are run in their own thread so can block as long
+  they like, do_command is run in the main clvmd thread so should not block for
+  too long. If the pre-command returns an error code (!=0) then the command
+  will not be propogated around the cluster but the post-command WILL be called
+
+  Also note that the pre and post routine are *always* called on the local
+  node, even if the command to be executed was only requested to run on a
+  remote node. It may peek inside the client structure to check the status of
+  the command.
+
+  The clients of the daemon must, naturally, understand the return messages and
+  codes.
+
+  Routines in here may only READ the values in the client structure passed in
+  apart from client->private which they are free to do what they like with.
+
+*/
+
+#include "clvmd-common.h"
+
+#include <pthread.h>
+
+#include "clvmd-comms.h"
+#include "clvm.h"
+#include "clvmd.h"
+#include "lvm-globals.h"
+#include "lvm-functions.h"
+
+#include "locking.h"
+
+#include <sys/utsname.h>
+
+extern struct cluster_ops *clops;
+static int restart_clvmd(void);
+
+/* This is where all the real work happens:
+   NOTE: client will be NULL when this is executed on a remote node */
+int do_command(struct local_client *client, struct clvm_header *msg, int msglen,
+	       char **buf, int buflen, int *retlen)
+{
+	char *args = msg->node + strlen(msg->node) + 1;
+	int arglen = msglen - sizeof(struct clvm_header) - strlen(msg->node);
+	int status = 0;
+	char *lockname;
+	const char *locktype;
+	struct utsname nodeinfo;
+	unsigned char lock_cmd;
+	unsigned char lock_flags;
+
+	/* Reset test mode before we start */
+	init_test(0);
+
+	/* Do the command */
+	switch (msg->cmd) {
+		/* Just a test message */
+	case CLVMD_CMD_TEST:
+		if (arglen > buflen) {
+			char *new_buf;
+			buflen = arglen + 200;
+			new_buf = realloc(*buf, buflen);
+			if (new_buf == NULL) {
+				status = errno;
+				free (*buf);
+			}
+			*buf = new_buf;
+		}
+		if (*buf) {
+			if (uname(&nodeinfo))
+				memset(&nodeinfo, 0, sizeof(nodeinfo));
+
+			*retlen = 1 + dm_snprintf(*buf, buflen,
+						  "TEST from %s: %s v%s",
+						  nodeinfo.nodename, args,
+						  nodeinfo.release);
+		}
+		break;
+
+	case CLVMD_CMD_LOCK_VG:
+		lock_cmd = args[0];
+		lock_flags = args[1];
+		lockname = &args[2];
+		/* Check to see if the VG is in use by LVM1 */
+		status = do_check_lvm1(lockname);
+		if (lock_flags & LCK_TEST_MODE)
+			init_test(1);
+		do_lock_vg(lock_cmd, lock_flags, lockname);
+		break;
+
+	case CLVMD_CMD_LOCK_LV:
+		/* This is the biggie */
+		lock_cmd = args[0];
+		lock_flags = args[1];
+		lockname = &args[2];
+		if (lock_flags & LCK_TEST_MODE)
+			init_test(1);
+		status = do_lock_lv(lock_cmd, lock_flags, lockname);
+		/* Replace EIO with something less scary */
+		if (status == EIO) {
+			*retlen = 1 + dm_snprintf(*buf, buflen, "%s",
+						  get_last_lvm_error());
+			return EIO;
+		}
+		break;
+
+	case CLVMD_CMD_LOCK_QUERY:
+		lockname = &args[2];
+		if (buflen < 3)
+			return EIO;
+		if ((locktype = do_lock_query(lockname)))
+			*retlen = 1 + dm_snprintf(*buf, buflen, "%s", locktype);
+		break;
+
+	case CLVMD_CMD_REFRESH:
+		do_refresh_cache();
+		break;
+
+	case CLVMD_CMD_SYNC_NAMES:
+		lvm_do_fs_unlock();
+		break;
+
+	case CLVMD_CMD_SET_DEBUG:
+		clvmd_set_debug(args[0]);
+		break;
+
+	case CLVMD_CMD_RESTART:
+		status = restart_clvmd();
+		break;
+
+	case CLVMD_CMD_GET_CLUSTERNAME:
+		status = clops->get_cluster_name(*buf, buflen);
+		if (!status)
+			*retlen = strlen(*buf)+1;
+		break;
+
+	case CLVMD_CMD_VG_BACKUP:
+		/*
+		 * Do not run backup on local node, caller should do that.
+		 */
+		if (!client)
+			lvm_do_backup(&args[2]);
+		break;
+
+	default:
+		/* Won't get here because command is validated in pre_command */
+		break;
+	}
+
+	/* Check the status of the command and return the error text */
+	if (status) {
+		*retlen = 1 + ((*buf) ? dm_snprintf(*buf, buflen, "%s",
+						    strerror(status)) : -1);
+	}
+
+	return status;
+
+}
+
+static int lock_vg(struct local_client *client)
+{
+    struct dm_hash_table *lock_hash;
+    struct clvm_header *header =
+	(struct clvm_header *) client->bits.localsock.cmd;
+    unsigned char lock_cmd;
+    int lock_mode;
+    char *args = header->node + strlen(header->node) + 1;
+    int lkid;
+    int status = 0;
+    char *lockname;
+
+    /* Keep a track of VG locks in our own hash table. In current
+       practice there should only ever be more than two VGs locked
+       if a user tries to merge lots of them at once */
+    if (client->bits.localsock.private) {
+	lock_hash = (struct dm_hash_table *)client->bits.localsock.private;
+    }
+    else {
+	lock_hash = dm_hash_create(3);
+	if (!lock_hash)
+	    return ENOMEM;
+	client->bits.localsock.private = (void *)lock_hash;
+    }
+
+    lock_cmd = args[0] & (LCK_NONBLOCK | LCK_HOLD | LCK_SCOPE_MASK | LCK_TYPE_MASK);
+    lock_mode = ((int)lock_cmd & LCK_TYPE_MASK);
+    /* lock_flags = args[1]; */
+    lockname = &args[2];
+    DEBUGLOG("doing PRE command LOCK_VG '%s' at %x (client=%p)\n", lockname, lock_cmd, client);
+
+    if (lock_mode == LCK_UNLOCK) {
+
+	lkid = (int)(long)dm_hash_lookup(lock_hash, lockname);
+	if (lkid == 0)
+	    return EINVAL;
+
+	status = sync_unlock(lockname, lkid);
+	if (status)
+	    status = errno;
+	else
+	    dm_hash_remove(lock_hash, lockname);
+    }
+    else {
+	/* Read locks need to be PR; other modes get passed through */
+	if (lock_mode == LCK_READ)
+	    lock_mode = LCK_PREAD;
+	status = sync_lock(lockname, lock_mode, (lock_cmd & LCK_NONBLOCK) ? LCKF_NOQUEUE : 0, &lkid);
+	if (status)
+	    status = errno;
+	else
+	    dm_hash_insert(lock_hash, lockname, (void *)(long)lkid);
+    }
+
+    return status;
+}
+
+
+/* Pre-command is a good place to get locks that are needed only for the duration
+   of the commands around the cluster (don't forget to free them in post-command),
+   and to sanity check the command arguments */
+int do_pre_command(struct local_client *client)
+{
+	struct clvm_header *header =
+	    (struct clvm_header *) client->bits.localsock.cmd;
+	unsigned char lock_cmd;
+	unsigned char lock_flags;
+	char *args = header->node + strlen(header->node) + 1;
+	int lockid = 0;
+	int status = 0;
+	char *lockname;
+
+	init_test(0);
+	switch (header->cmd) {
+	case CLVMD_CMD_TEST:
+		status = sync_lock("CLVMD_TEST", LCK_EXCL, 0, &lockid);
+		client->bits.localsock.private = (void *)(long)lockid;
+		break;
+
+	case CLVMD_CMD_LOCK_VG:
+		lockname = &args[2];
+		/* We take out a real lock unless LCK_CACHE was set */
+		if (!strncmp(lockname, "V_", 2) ||
+		    !strncmp(lockname, "P_#", 3))
+			status = lock_vg(client);
+		break;
+
+	case CLVMD_CMD_LOCK_LV:
+		lock_cmd = args[0];
+		lock_flags = args[1];
+		lockname = &args[2];
+		if (lock_flags & LCK_TEST_MODE)
+			init_test(1);
+		status = pre_lock_lv(lock_cmd, lock_flags, lockname);
+		break;
+
+	case CLVMD_CMD_REFRESH:
+	case CLVMD_CMD_GET_CLUSTERNAME:
+	case CLVMD_CMD_SET_DEBUG:
+	case CLVMD_CMD_VG_BACKUP:
+	case CLVMD_CMD_SYNC_NAMES:
+	case CLVMD_CMD_LOCK_QUERY:
+	case CLVMD_CMD_RESTART:
+		break;
+
+	default:
+		log_error("Unknown command %d received\n", header->cmd);
+		status = EINVAL;
+	}
+	return status;
+}
+
+/* Note that the post-command routine is called even if the pre-command or the real command
+   failed */
+int do_post_command(struct local_client *client)
+{
+	struct clvm_header *header =
+	    (struct clvm_header *) client->bits.localsock.cmd;
+	int status = 0;
+	unsigned char lock_cmd;
+	unsigned char lock_flags;
+	char *args = header->node + strlen(header->node) + 1;
+	char *lockname;
+
+	init_test(0);
+	switch (header->cmd) {
+	case CLVMD_CMD_TEST:
+		status =
+		    sync_unlock("CLVMD_TEST", (int) (long) client->bits.localsock.private);
+		client->bits.localsock.private = 0;
+		break;
+
+	case CLVMD_CMD_LOCK_LV:
+		lock_cmd = args[0];
+		lock_flags = args[1];
+		lockname = &args[2];
+		if (lock_flags & LCK_TEST_MODE)
+			init_test(1);
+		status = post_lock_lv(lock_cmd, lock_flags, lockname);
+		break;
+
+	default:
+		/* Nothing to do here */
+		break;
+	}
+	return status;
+}
+
+
+/* Called when the client is about to be deleted */
+void cmd_client_cleanup(struct local_client *client)
+{
+    if (client->bits.localsock.private) {
+
+	struct dm_hash_node *v;
+	struct dm_hash_table *lock_hash =
+	    (struct dm_hash_table *)client->bits.localsock.private;
+
+	dm_hash_iterate(v, lock_hash) {
+		int lkid = (int)(long)dm_hash_get_data(lock_hash, v);
+		char *lockname = dm_hash_get_key(lock_hash, v);
+
+		DEBUGLOG("cleanup: Unlocking lock %s %x\n", lockname, lkid);
+		sync_unlock(lockname, lkid);
+	}
+
+	dm_hash_destroy(lock_hash);
+	client->bits.localsock.private = 0;
+    }
+}
+
+
+static int restart_clvmd(void)
+{
+	const char **argv;
+	char *lv_name;
+	int argc = 0, max_locks = 0;
+	struct dm_hash_node *hn = NULL;
+	char debug_arg[16];
+	const char *clvmd = getenv("LVM_CLVMD_BINARY") ? : CLVMD_PATH;
+
+	DEBUGLOG("clvmd restart requested\n");
+
+	/* Count exclusively-open LVs */
+	do {
+		hn = get_next_excl_lock(hn, &lv_name);
+		if (lv_name) {
+			max_locks++;
+			if (!*lv_name)
+				break; /* FIXME: Is this error ? */
+		}
+	} while (hn);
+
+	/* clvmd + locks (-E uuid) + debug (-d X) + NULL */
+	if (!(argv = malloc((max_locks * 2 + 5) * sizeof(*argv))))
+		goto_out;
+
+	/*
+	 * Build the command-line
+	 */
+	argv[argc++] = "clvmd";
+
+	/* Propogate debug options */
+	if (clvmd_get_debug()) {
+		if (dm_snprintf(debug_arg, sizeof(debug_arg), "-d%u", clvmd_get_debug()) < 0)
+			goto_out;
+		argv[argc++] = debug_arg;
+	}
+
+	argv[argc++] = "-I";
+	argv[argc++] = clops->name;
+
+	/* Now add the exclusively-open LVs */
+	hn = NULL;
+	do {
+		hn = get_next_excl_lock(hn, &lv_name);
+		if (lv_name) {
+			if (!*lv_name)
+				break; /* FIXME: Is this error ? */
+			argv[argc++] = "-E";
+			argv[argc++] = lv_name;
+			DEBUGLOG("excl lock: %s\n", lv_name);
+		}
+	} while (hn);
+	argv[argc] = NULL;
+
+	/* Exec new clvmd */
+	DEBUGLOG("--- Restarting %s ---\n", clvmd);
+	for (argc = 1; argv[argc]; argc++) DEBUGLOG("--- %d: %s\n", argc, argv[argc]);
+
+	/* NOTE: This will fail when downgrading! */
+	execvp(clvmd, (char **)argv);
+out:
+	/* We failed */
+	DEBUGLOG("Restart of clvmd failed.\n");
+
+	free(argv);
+
+	return EIO;
+}

daemons/clvmd/clvmd-common.h

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2010 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/*
+ * This file must be included first by every clvmd source file.
+ */
+#ifndef _LVM_CLVMD_COMMON_H
+#define _LVM_CLVMD_COMMON_H
+
+#include "configure.h"
+
+#define _GNU_SOURCE
+#define _FILE_OFFSET_BITS 64
+
+#include "libdevmapper.h"
+
+#include "lvm-logging.h"
+
+#include <unistd.h>
+#include <sys/stat.h>
+
+#endif

daemons/clvmd/clvmd-comms.h

@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 2002-2004 Sistina Software, Inc. All rights reserved.
+ * Copyright (C) 2004-2011 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/*
+ * Abstraction layer for clvmd cluster communications
+ */
+
+#ifndef _CLVMD_COMMS_H
+#define _CLVMD_COMMS_H
+
+struct local_client;
+
+struct cluster_ops {
+	const char *name;
+	void (*cluster_init_completed) (void);
+
+	int (*cluster_send_message) (const void *buf, int msglen,
+				     const char *csid,
+				     const char *errtext);
+	int (*name_from_csid) (const char *csid, char *name);
+	int (*csid_from_name) (char *csid, const char *name);
+	int (*get_num_nodes) (void);
+	int (*cluster_fd_callback) (struct local_client *fd, char *buf, int len,
+				    const char *csid,
+				    struct local_client **new_client);
+	int (*get_main_cluster_fd) (void);	/* gets accept FD or cman cluster socket */
+	int (*cluster_do_node_callback) (struct local_client *client,
+					 void (*callback) (struct local_client *,
+							   const char *csid,
+							   int node_up));
+	int (*is_quorate) (void);
+
+	void (*get_our_csid) (char *csid);
+	void (*add_up_node) (const char *csid);
+	void (*reread_config) (void);
+	void (*cluster_closedown) (void);
+
+	int (*get_cluster_name)(char *buf, int buflen);
+
+	int (*sync_lock) (const char *resource, int mode,
+			  int flags, int *lockid);
+	int (*sync_unlock) (const char *resource, int lockid);
+
+};
+
+#ifdef USE_CMAN
+#  include <netinet/in.h>
+#  include "libcman.h"
+#  define CMAN_MAX_CSID_LEN 4
+#  ifndef MAX_CSID_LEN
+#    define MAX_CSID_LEN CMAN_MAX_CSID_LEN
+#  endif
+#  undef MAX_CLUSTER_MEMBER_NAME_LEN
+#  define MAX_CLUSTER_MEMBER_NAME_LEN   CMAN_MAX_NODENAME_LEN
+#  define CMAN_MAX_CLUSTER_MESSAGE 1500
+#  define CLUSTER_PORT_CLVMD 11
+struct cluster_ops *init_cman_cluster(void);
+#endif
+
+#ifdef USE_OPENAIS
+#  include <openais/saAis.h>
+#  include <corosync/totem/totem.h>
+#  define OPENAIS_CSID_LEN (sizeof(int))
+#  define OPENAIS_MAX_CLUSTER_MESSAGE         MESSAGE_SIZE_MAX
+#  define OPENAIS_MAX_CLUSTER_MEMBER_NAME_LEN SA_MAX_NAME_LENGTH
+#  ifndef MAX_CLUSTER_MEMBER_NAME_LEN
+#    define MAX_CLUSTER_MEMBER_NAME_LEN       SA_MAX_NAME_LENGTH
+#  endif
+#  ifndef CMAN_MAX_CLUSTER_MESSAGE
+#    define CMAN_MAX_CLUSTER_MESSAGE          MESSAGE_SIZE_MAX
+#  endif
+#  ifndef MAX_CSID_LEN
+#    define MAX_CSID_LEN sizeof(int)
+#  endif
+struct cluster_ops *init_openais_cluster(void);
+#endif
+
+#ifdef USE_COROSYNC
+#  include <corosync/corotypes.h>
+#  define COROSYNC_CSID_LEN (sizeof(int))
+#  define COROSYNC_MAX_CLUSTER_MESSAGE         65535
+#  define COROSYNC_MAX_CLUSTER_MEMBER_NAME_LEN CS_MAX_NAME_LENGTH
+#  ifndef MAX_CLUSTER_MEMBER_NAME_LEN
+#    define MAX_CLUSTER_MEMBER_NAME_LEN       CS_MAX_NAME_LENGTH
+#  endif
+#  ifndef CMAN_MAX_CLUSTER_MESSAGE
+#    define CMAN_MAX_CLUSTER_MESSAGE          65535
+#  endif
+#  ifndef MAX_CSID_LEN
+#    define MAX_CSID_LEN sizeof(int)
+#  endif
+struct cluster_ops *init_corosync_cluster(void);
+#endif
+
+#ifdef USE_SINGLENODE
+#  define SINGLENODE_CSID_LEN (sizeof(int))
+#  ifndef MAX_CLUSTER_MEMBER_NAME_LEN
+#    define MAX_CLUSTER_MEMBER_NAME_LEN       64
+#  endif
+#  define SINGLENODE_MAX_CLUSTER_MESSAGE          65535
+#  ifndef MAX_CSID_LEN
+#    define MAX_CSID_LEN sizeof(int)
+#  endif
+struct cluster_ops *init_singlenode_cluster(void);
+#endif
+
+#endif

daemons/clvmd/clvmd-corosync.c

@@ -0,0 +1,684 @@
+/*
+ * Copyright (C) 2009-2012 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/*
+ * This provides the interface between clvmd and corosync/DLM as the cluster
+ * and lock manager.
+ */
+
+#include "clvmd-common.h"
+
+#include <pthread.h>
+
+#include "clvm.h"
+#include "clvmd-comms.h"
+#include "clvmd.h"
+#include "lvm-functions.h"
+
+#include "locking.h"
+
+#include <corosync/cpg.h>
+#include <corosync/quorum.h>
+
+#ifdef HAVE_COROSYNC_CONFDB_H
+#  include <corosync/confdb.h>
+#elif defined HAVE_COROSYNC_CMAP_H
+#  include <corosync/cmap.h>
+#else
+#  error "Either HAVE_COROSYNC_CONFDB_H or HAVE_COROSYNC_CMAP_H must be defined."
+#endif
+
+#include <libdlm.h>
+
+#include <syslog.h>
+
+/* Timeout value for several corosync calls */
+#define LOCKSPACE_NAME "clvmd"
+
+static void corosync_cpg_deliver_callback (cpg_handle_t handle,
+				  const struct cpg_name *groupName,
+				  uint32_t nodeid,
+				  uint32_t pid,
+				  void *msg,
+				  size_t msg_len);
+static void corosync_cpg_confchg_callback(cpg_handle_t handle,
+				 const struct cpg_name *groupName,
+				 const struct cpg_address *member_list, size_t member_list_entries,
+				 const struct cpg_address *left_list, size_t left_list_entries,
+				 const struct cpg_address *joined_list, size_t joined_list_entries);
+static void _cluster_closedown(void);
+
+/* Hash list of nodes in the cluster */
+static struct dm_hash_table *node_hash;
+
+/* Number of active nodes */
+static int num_nodes;
+static unsigned int our_nodeid;
+
+static struct local_client *cluster_client;
+
+/* Corosync handles */
+static cpg_handle_t cpg_handle;
+static quorum_handle_t quorum_handle;
+
+/* DLM Handle */
+static dlm_lshandle_t *lockspace;
+
+static struct cpg_name cpg_group_name;
+
+/* Corosync callback structs */
+cpg_callbacks_t corosync_cpg_callbacks = {
+	.cpg_deliver_fn =            corosync_cpg_deliver_callback,
+	.cpg_confchg_fn =            corosync_cpg_confchg_callback,
+};
+
+quorum_callbacks_t quorum_callbacks = {
+	.quorum_notify_fn = NULL,
+};
+
+struct node_info
+{
+	enum {NODE_UNKNOWN, NODE_DOWN, NODE_UP, NODE_CLVMD} state;
+	int nodeid;
+};
+
+
+/* Set errno to something approximating the right value and return 0 or -1 */
+static int cs_to_errno(cs_error_t err)
+{
+	switch(err)
+	{
+	case CS_OK:
+		return 0;
+        case CS_ERR_LIBRARY:
+		errno = EINVAL;
+		break;
+        case CS_ERR_VERSION:
+		errno = EINVAL;
+		break;
+        case CS_ERR_INIT:
+		errno = EINVAL;
+		break;
+        case CS_ERR_TIMEOUT:
+		errno = ETIME;
+		break;
+        case CS_ERR_TRY_AGAIN:
+		errno = EAGAIN;
+		break;
+        case CS_ERR_INVALID_PARAM:
+		errno = EINVAL;
+		break;
+        case CS_ERR_NO_MEMORY:
+		errno = ENOMEM;
+		break;
+        case CS_ERR_BAD_HANDLE:
+		errno = EINVAL;
+		break;
+        case CS_ERR_BUSY:
+		errno = EBUSY;
+		break;
+        case CS_ERR_ACCESS:
+		errno = EPERM;
+		break;
+        case CS_ERR_NOT_EXIST:
+		errno = ENOENT;
+		break;
+        case CS_ERR_NAME_TOO_LONG:
+		errno = ENAMETOOLONG;
+		break;
+        case CS_ERR_EXIST:
+		errno = EEXIST;
+		break;
+        case CS_ERR_NO_SPACE:
+		errno = ENOSPC;
+		break;
+        case CS_ERR_INTERRUPT:
+		errno = EINTR;
+		break;
+	case CS_ERR_NAME_NOT_FOUND:
+		errno = ENOENT;
+		break;
+        case CS_ERR_NO_RESOURCES:
+		errno = ENOMEM;
+		break;
+        case CS_ERR_NOT_SUPPORTED:
+		errno = EOPNOTSUPP;
+		break;
+        case CS_ERR_BAD_OPERATION:
+		errno = EINVAL;
+		break;
+        case CS_ERR_FAILED_OPERATION:
+		errno = EIO;
+		break;
+        case CS_ERR_MESSAGE_ERROR:
+		errno = EIO;
+		break;
+        case CS_ERR_QUEUE_FULL:
+		errno = EXFULL;
+		break;
+        case CS_ERR_QUEUE_NOT_AVAILABLE:
+		errno = EINVAL;
+		break;
+        case CS_ERR_BAD_FLAGS:
+		errno = EINVAL;
+		break;
+        case CS_ERR_TOO_BIG:
+		errno = E2BIG;
+		break;
+        case CS_ERR_NO_SECTIONS:
+		errno = ENOMEM;
+		break;
+	default:
+		errno = EINVAL;
+		break;
+	}
+	return -1;
+}
+
+static char *print_corosync_csid(const char *csid)
+{
+	static char buf[128];
+	int id;
+
+	memcpy(&id, csid, sizeof(int));
+	sprintf(buf, "%d", id);
+	return buf;
+}
+
+static void corosync_cpg_deliver_callback (cpg_handle_t handle,
+				  const struct cpg_name *groupName,
+				  uint32_t nodeid,
+				  uint32_t pid,
+				  void *msg,
+				  size_t msg_len)
+{
+	int target_nodeid;
+
+	memcpy(&target_nodeid, msg, COROSYNC_CSID_LEN);
+
+	DEBUGLOG("%u got message from nodeid %d for %d. len %zd\n",
+		 our_nodeid, nodeid, target_nodeid, msg_len-4);
+
+	if (nodeid != our_nodeid)
+		if (target_nodeid == our_nodeid || target_nodeid == 0)
+			process_message(cluster_client, (char *)msg+COROSYNC_CSID_LEN,
+					msg_len-COROSYNC_CSID_LEN, (char*)&nodeid);
+}
+
+static void corosync_cpg_confchg_callback(cpg_handle_t handle,
+				 const struct cpg_name *groupName,
+				 const struct cpg_address *member_list, size_t member_list_entries,
+				 const struct cpg_address *left_list, size_t left_list_entries,
+				 const struct cpg_address *joined_list, size_t joined_list_entries)
+{
+	int i;
+	struct node_info *ninfo;
+
+	DEBUGLOG("confchg callback. %zd joined, %zd left, %zd members\n",
+		 joined_list_entries, left_list_entries, member_list_entries);
+
+	for (i=0; i<joined_list_entries; i++) {
+		ninfo = dm_hash_lookup_binary(node_hash,
+					      (char *)&joined_list[i].nodeid,
+					      COROSYNC_CSID_LEN);
+		if (!ninfo) {
+			ninfo = malloc(sizeof(struct node_info));
+			if (!ninfo) {
+				break;
+			}
+			else {
+				ninfo->nodeid = joined_list[i].nodeid;
+				dm_hash_insert_binary(node_hash,
+						      (char *)&ninfo->nodeid,
+						      COROSYNC_CSID_LEN, ninfo);
+			}
+		}
+		ninfo->state = NODE_CLVMD;
+	}
+
+	for (i=0; i<left_list_entries; i++) {
+		ninfo = dm_hash_lookup_binary(node_hash,
+					      (char *)&left_list[i].nodeid,
+					      COROSYNC_CSID_LEN);
+		if (ninfo)
+			ninfo->state = NODE_DOWN;
+	}
+
+	for (i=0; i<member_list_entries; i++) {
+		if (member_list[i].nodeid == 0) continue;
+		ninfo = dm_hash_lookup_binary(node_hash,
+				(char *)&member_list[i].nodeid,
+				COROSYNC_CSID_LEN);
+		if (!ninfo) {
+			ninfo = malloc(sizeof(struct node_info));
+			if (!ninfo) {
+				break;
+			}
+			else {
+				ninfo->nodeid = member_list[i].nodeid;
+				dm_hash_insert_binary(node_hash,
+						(char *)&ninfo->nodeid,
+						COROSYNC_CSID_LEN, ninfo);
+			}
+		}
+		ninfo->state = NODE_CLVMD;
+	}
+
+	num_nodes = member_list_entries;
+}
+
+static int _init_cluster(void)
+{
+	cs_error_t err;
+
+#ifdef QUORUM_SET	/* corosync/quorum.h */
+	uint32_t quorum_type;
+#endif
+
+	node_hash = dm_hash_create(100);
+
+	err = cpg_initialize(&cpg_handle,
+			     &corosync_cpg_callbacks);
+	if (err != CS_OK) {
+		syslog(LOG_ERR, "Cannot initialise Corosync CPG service: %d",
+		       err);
+		DEBUGLOG("Cannot initialise Corosync CPG service: %d", err);
+		return cs_to_errno(err);
+	}
+
+#ifdef QUORUM_SET
+	err = quorum_initialize(&quorum_handle,
+				&quorum_callbacks,
+				&quorum_type);
+
+	if (quorum_type != QUORUM_SET) {
+		syslog(LOG_ERR, "Corosync quorum service is not configured");
+		DEBUGLOG("Corosync quorum service is not configured");
+		return EINVAL;
+	}
+#else
+	err = quorum_initialize(&quorum_handle,
+				&quorum_callbacks);
+#endif
+
+	if (err != CS_OK) {
+		syslog(LOG_ERR, "Cannot initialise Corosync quorum service: %d",
+		       err);
+		DEBUGLOG("Cannot initialise Corosync quorum service: %d", err);
+		return cs_to_errno(err);
+	}
+
+	/* Create a lockspace for LV & VG locks to live in */
+	lockspace = dlm_open_lockspace(LOCKSPACE_NAME);
+	if (!lockspace) {
+		lockspace = dlm_create_lockspace(LOCKSPACE_NAME, 0600);
+		if (!lockspace) {
+			syslog(LOG_ERR, "Unable to create DLM lockspace for CLVM: %m");
+			return -1;
+		}
+		DEBUGLOG("Created DLM lockspace for CLVMD.\n");
+	} else
+		DEBUGLOG("Opened existing DLM lockspace for CLVMD.\n");
+
+	dlm_ls_pthread_init(lockspace);
+	DEBUGLOG("DLM initialisation complete\n");
+
+	/* Connect to the clvmd group */
+	strcpy((char *)cpg_group_name.value, "clvmd");
+	cpg_group_name.length = strlen((char *)cpg_group_name.value);
+	err = cpg_join(cpg_handle, &cpg_group_name);
+	if (err != CS_OK) {
+		cpg_finalize(cpg_handle);
+		quorum_finalize(quorum_handle);
+		dlm_release_lockspace(LOCKSPACE_NAME, lockspace, 1);
+		syslog(LOG_ERR, "Cannot join clvmd process group");
+		DEBUGLOG("Cannot join clvmd process group: %d\n", err);
+		return cs_to_errno(err);
+	}
+
+	err = cpg_local_get(cpg_handle,
+			    &our_nodeid);
+	if (err != CS_OK) {
+		cpg_finalize(cpg_handle);
+		quorum_finalize(quorum_handle);
+		dlm_release_lockspace(LOCKSPACE_NAME, lockspace, 1);
+		syslog(LOG_ERR, "Cannot get local node id\n");
+		return cs_to_errno(err);
+	}
+	DEBUGLOG("Our local node id is %d\n", our_nodeid);
+
+	DEBUGLOG("Connected to Corosync\n");
+
+	return 0;
+}
+
+static void _cluster_closedown(void)
+{
+	DEBUGLOG("cluster_closedown\n");
+	destroy_lvhash();
+
+	dlm_release_lockspace(LOCKSPACE_NAME, lockspace, 1);
+	cpg_finalize(cpg_handle);
+	quorum_finalize(quorum_handle);
+}
+
+static void _get_our_csid(char *csid)
+{
+	memcpy(csid, &our_nodeid, sizeof(int));
+}
+
+/* Corosync doesn't really have nmode names so we
+   just use the node ID in hex instead */
+static int _csid_from_name(char *csid, const char *name)
+{
+	int nodeid;
+	struct node_info *ninfo;
+
+	if (sscanf(name, "%x", &nodeid) == 1) {
+		ninfo = dm_hash_lookup_binary(node_hash, csid, COROSYNC_CSID_LEN);
+		if (ninfo)
+			return nodeid;
+	}
+	return -1;
+}
+
+static int _name_from_csid(const char *csid, char *name)
+{
+	struct node_info *ninfo;
+
+	ninfo = dm_hash_lookup_binary(node_hash, csid, COROSYNC_CSID_LEN);
+	if (!ninfo)
+	{
+		sprintf(name, "UNKNOWN %s", print_corosync_csid(csid));
+		return -1;
+	}
+
+	sprintf(name, "%x", ninfo->nodeid);
+	return 0;
+}
+
+static int _get_num_nodes()
+{
+	DEBUGLOG("num_nodes = %d\n", num_nodes);
+	return num_nodes;
+}
+
+/* Node is now known to be running a clvmd */
+static void _add_up_node(const char *csid)
+{
+	struct node_info *ninfo;
+
+	ninfo = dm_hash_lookup_binary(node_hash, csid, COROSYNC_CSID_LEN);
+	if (!ninfo) {
+		DEBUGLOG("corosync_add_up_node no node_hash entry for csid %s\n",
+			 print_corosync_csid(csid));
+		return;
+	}
+
+	DEBUGLOG("corosync_add_up_node %d\n", ninfo->nodeid);
+
+	ninfo->state = NODE_CLVMD;
+
+	return;
+}
+
+/* Call a callback for each node, so the caller knows whether it's up or down */
+static int _cluster_do_node_callback(struct local_client *master_client,
+				     void (*callback)(struct local_client *,
+						      const char *csid, int node_up))
+{
+	struct dm_hash_node *hn;
+	struct node_info *ninfo;
+	int somedown = 0;
+
+	dm_hash_iterate(hn, node_hash)
+	{
+		char csid[COROSYNC_CSID_LEN];
+
+		ninfo = dm_hash_get_data(node_hash, hn);
+		memcpy(csid, dm_hash_get_key(node_hash, hn), COROSYNC_CSID_LEN);
+
+		DEBUGLOG("down_callback. node %d, state = %d\n", ninfo->nodeid,
+			 ninfo->state);
+
+		if (ninfo->state != NODE_DOWN)
+			callback(master_client, csid, ninfo->state == NODE_CLVMD);
+		if (ninfo->state != NODE_CLVMD)
+			somedown = -1;
+	}
+	return somedown;
+}
+
+/* Real locking */
+static int _lock_resource(const char *resource, int mode, int flags, int *lockid)
+{
+	struct dlm_lksb lksb;
+	int err;
+
+	DEBUGLOG("lock_resource '%s', flags=%d, mode=%d\n", resource, flags, mode);
+
+	if (flags & LKF_CONVERT)
+		lksb.sb_lkid = *lockid;
+
+	err = dlm_ls_lock_wait(lockspace,
+			       mode,
+			       &lksb,
+			       flags,
+			       resource,
+			       strlen(resource),
+			       0,
+			       NULL, NULL, NULL);
+
+	if (err != 0)
+	{
+		DEBUGLOG("dlm_ls_lock returned %d\n", errno);
+		return err;
+	}
+	if (lksb.sb_status != 0)
+	{
+		DEBUGLOG("dlm_ls_lock returns lksb.sb_status %d\n", lksb.sb_status);
+		errno = lksb.sb_status;
+		return -1;
+	}
+
+	DEBUGLOG("lock_resource returning %d, lock_id=%x\n", err, lksb.sb_lkid);
+
+	*lockid = lksb.sb_lkid;
+
+	return 0;
+}
+
+
+static int _unlock_resource(const char *resource, int lockid)
+{
+	struct dlm_lksb lksb;
+	int err;
+
+	DEBUGLOG("unlock_resource: %s lockid: %x\n", resource, lockid);
+	lksb.sb_lkid = lockid;
+
+	err = dlm_ls_unlock_wait(lockspace,
+				 lockid,
+				 0,
+				 &lksb);
+	if (err != 0)
+	{
+		DEBUGLOG("Unlock returned %d\n", err);
+		return err;
+	}
+	if (lksb.sb_status != EUNLOCK)
+	{
+		DEBUGLOG("dlm_ls_unlock_wait returns lksb.sb_status: %d\n", lksb.sb_status);
+		errno = lksb.sb_status;
+		return -1;
+	}   
+
+
+	return 0;
+}
+
+static int _is_quorate()
+{
+	int quorate;
+	if (quorum_getquorate(quorum_handle, &quorate) == CS_OK)
+		return quorate;
+	else
+		return 0;
+}
+
+static int _get_main_cluster_fd(void)
+{
+	int select_fd;
+
+	cpg_fd_get(cpg_handle, &select_fd);
+	return select_fd;
+}
+
+static int _cluster_fd_callback(struct local_client *fd, char *buf, int len,
+				const char *csid,
+				struct local_client **new_client)
+{
+	cluster_client = fd;
+	*new_client = NULL;
+	cpg_dispatch(cpg_handle, CS_DISPATCH_ONE);
+	return 1;
+}
+
+static int _cluster_send_message(const void *buf, int msglen, const char *csid,
+				 const char *errtext)
+{
+	struct iovec iov[2];
+	cs_error_t err;
+	int target_node;
+
+	if (csid)
+		memcpy(&target_node, csid, COROSYNC_CSID_LEN);
+	else
+		target_node = 0;
+
+	iov[0].iov_base = &target_node;
+	iov[0].iov_len = sizeof(int);
+	iov[1].iov_base = (char *)buf;
+	iov[1].iov_len = msglen;
+
+	err = cpg_mcast_joined(cpg_handle, CPG_TYPE_AGREED, iov, 2);
+	return cs_to_errno(err);
+}
+
+#ifdef HAVE_COROSYNC_CONFDB_H
+/*
+ * We are not necessarily connected to a Red Hat Cluster system,
+ * but if we are, this returns the cluster name from cluster.conf.
+ * I've used confdb rather than ccs to reduce the inter-package
+ * dependancies as well as to allow people to set a cluster name
+ * for themselves even if they are not running on RH cluster.
+ */
+static int _get_cluster_name(char *buf, int buflen)
+{
+	confdb_handle_t handle;
+	int result;
+	size_t namelen = buflen;
+	hdb_handle_t cluster_handle;
+	confdb_callbacks_t callbacks = {
+		.confdb_key_change_notify_fn = NULL,
+		.confdb_object_create_change_notify_fn = NULL,
+		.confdb_object_delete_change_notify_fn = NULL
+	};
+
+	/* This is a default in case everything else fails */
+	strncpy(buf, "Corosync", buflen);
+
+	/* Look for a cluster name in confdb */
+	result = confdb_initialize (&handle, &callbacks);
+        if (result != CS_OK)
+		return 0;
+
+        result = confdb_object_find_start(handle, OBJECT_PARENT_HANDLE);
+	if (result != CS_OK)
+		goto out;
+
+        result = confdb_object_find(handle, OBJECT_PARENT_HANDLE, (void *)"cluster", strlen("cluster"), &cluster_handle);
+        if (result != CS_OK)
+		goto out;
+
+        result = confdb_key_get(handle, cluster_handle, (void *)"name", strlen("name"), buf, &namelen);
+        if (result != CS_OK)
+		goto out;
+
+	buf[namelen] = '\0';
+
+out:
+	confdb_finalize(handle);
+	return 0;
+}
+
+#elif defined HAVE_COROSYNC_CMAP_H
+
+static int _get_cluster_name(char *buf, int buflen)
+{
+	cmap_handle_t cmap_handle = 0;
+	int result;
+	char *name = NULL;
+
+	/* This is a default in case everything else fails */
+	strncpy(buf, "Corosync", buflen);
+
+	/* Look for a cluster name in cmap */
+	result = cmap_initialize(&cmap_handle);
+	if (result != CS_OK)
+		return 0;
+
+	result = cmap_get_string(cmap_handle, "totem.cluster_name", &name);
+	if (result != CS_OK)
+		goto out;
+
+	memset(buf, 0, buflen);
+	strncpy(buf, name, buflen - 1);
+
+out:
+	if (name)
+		free(name);
+	cmap_finalize(cmap_handle);
+	return 0;
+}
+
+#endif
+
+static struct cluster_ops _cluster_corosync_ops = {
+	.name                     = "corosync",
+	.cluster_init_completed   = NULL,
+	.cluster_send_message     = _cluster_send_message,
+	.name_from_csid           = _name_from_csid,
+	.csid_from_name           = _csid_from_name,
+	.get_num_nodes            = _get_num_nodes,
+	.cluster_fd_callback      = _cluster_fd_callback,
+	.get_main_cluster_fd      = _get_main_cluster_fd,
+	.cluster_do_node_callback = _cluster_do_node_callback,
+	.is_quorate               = _is_quorate,
+	.get_our_csid             = _get_our_csid,
+	.add_up_node              = _add_up_node,
+	.reread_config            = NULL,
+	.cluster_closedown        = _cluster_closedown,
+	.get_cluster_name         = _get_cluster_name,
+	.sync_lock                = _lock_resource,
+	.sync_unlock              = _unlock_resource,
+};
+
+struct cluster_ops *init_corosync_cluster(void)
+{
+	if (!_init_cluster())
+		return &_cluster_corosync_ops;
+	else
+		return NULL;
+}

daemons/clvmd/clvmd-openais.c

@@ -0,0 +1,695 @@
+/*
+ * Copyright (C) 2007-2009 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/*
+ * This provides the interface between clvmd and OpenAIS as the cluster
+ * and lock manager.
+ */
+
+#include "clvmd-common.h"
+
+#include <pthread.h>
+#include <fcntl.h>
+#include <syslog.h>
+
+#include <openais/saAis.h>
+#include <openais/saLck.h>
+
+#include <corosync/corotypes.h>
+#include <corosync/cpg.h>
+
+#include "locking.h"
+#include "clvm.h"
+#include "clvmd-comms.h"
+#include "lvm-functions.h"
+#include "clvmd.h"
+
+/* Timeout value for several openais calls */
+#define TIMEOUT 10
+
+static void openais_cpg_deliver_callback (cpg_handle_t handle,
+				  const struct cpg_name *groupName,
+				  uint32_t nodeid,
+				  uint32_t pid,
+				  void *msg,
+				  size_t msg_len);
+static void openais_cpg_confchg_callback(cpg_handle_t handle,
+				 const struct cpg_name *groupName,
+				 const struct cpg_address *member_list, size_t member_list_entries,
+				 const struct cpg_address *left_list, size_t left_list_entries,
+				 const struct cpg_address *joined_list, size_t joined_list_entries);
+
+static void _cluster_closedown(void);
+
+/* Hash list of nodes in the cluster */
+static struct dm_hash_table *node_hash;
+
+/* For associating lock IDs & resource handles */
+static struct dm_hash_table *lock_hash;
+
+/* Number of active nodes */
+static int num_nodes;
+static unsigned int our_nodeid;
+
+static struct local_client *cluster_client;
+
+/* OpenAIS handles */
+static cpg_handle_t cpg_handle;
+static SaLckHandleT lck_handle;
+
+static struct cpg_name cpg_group_name;
+
+/* Openais callback structs */
+cpg_callbacks_t openais_cpg_callbacks = {
+	.cpg_deliver_fn =            openais_cpg_deliver_callback,
+	.cpg_confchg_fn =            openais_cpg_confchg_callback,
+};
+
+struct node_info
+{
+	enum {NODE_UNKNOWN, NODE_DOWN, NODE_UP, NODE_CLVMD} state;
+	int nodeid;
+};
+
+struct lock_info
+{
+	SaLckResourceHandleT res_handle;
+	SaLckLockIdT         lock_id;
+	SaNameT              lock_name;
+};
+
+/* Set errno to something approximating the right value and return 0 or -1 */
+static int ais_to_errno(SaAisErrorT err)
+{
+	switch(err)
+	{
+	case SA_AIS_OK:
+		return 0;
+        case SA_AIS_ERR_LIBRARY:
+		errno = EINVAL;
+		break;
+        case SA_AIS_ERR_VERSION:
+		errno = EINVAL;
+		break;
+        case SA_AIS_ERR_INIT:
+		errno = EINVAL;
+		break;
+        case SA_AIS_ERR_TIMEOUT:
+		errno = ETIME;
+		break;
+        case SA_AIS_ERR_TRY_AGAIN:
+		errno = EAGAIN;
+		break;
+        case SA_AIS_ERR_INVALID_PARAM:
+		errno = EINVAL;
+		break;
+        case SA_AIS_ERR_NO_MEMORY:
+		errno = ENOMEM;
+		break;
+        case SA_AIS_ERR_BAD_HANDLE:
+		errno = EINVAL;
+		break;
+        case SA_AIS_ERR_BUSY:
+		errno = EBUSY;
+		break;
+        case SA_AIS_ERR_ACCESS:
+		errno = EPERM;
+		break;
+        case SA_AIS_ERR_NOT_EXIST:
+		errno = ENOENT;
+		break;
+        case SA_AIS_ERR_NAME_TOO_LONG:
+		errno = ENAMETOOLONG;
+		break;
+        case SA_AIS_ERR_EXIST:
+		errno = EEXIST;
+		break;
+        case SA_AIS_ERR_NO_SPACE:
+		errno = ENOSPC;
+		break;
+        case SA_AIS_ERR_INTERRUPT:
+		errno = EINTR;
+		break;
+	case SA_AIS_ERR_NAME_NOT_FOUND:
+		errno = ENOENT;
+		break;
+        case SA_AIS_ERR_NO_RESOURCES:
+		errno = ENOMEM;
+		break;
+        case SA_AIS_ERR_NOT_SUPPORTED:
+		errno = EOPNOTSUPP;
+		break;
+        case SA_AIS_ERR_BAD_OPERATION:
+		errno = EINVAL;
+		break;
+        case SA_AIS_ERR_FAILED_OPERATION:
+		errno = EIO;
+		break;
+        case SA_AIS_ERR_MESSAGE_ERROR:
+		errno = EIO;
+		break;
+        case SA_AIS_ERR_QUEUE_FULL:
+		errno = EXFULL;
+		break;
+        case SA_AIS_ERR_QUEUE_NOT_AVAILABLE:
+		errno = EINVAL;
+		break;
+        case SA_AIS_ERR_BAD_FLAGS:
+		errno = EINVAL;
+		break;
+        case SA_AIS_ERR_TOO_BIG:
+		errno = E2BIG;
+		break;
+        case SA_AIS_ERR_NO_SECTIONS:
+		errno = ENOMEM;
+		break;
+	default:
+		errno = EINVAL;
+		break;
+	}
+	return -1;
+}
+
+static char *print_openais_csid(const char *csid)
+{
+	static char buf[128];
+	int id;
+
+	memcpy(&id, csid, sizeof(int));
+	sprintf(buf, "%d", id);
+	return buf;
+}
+
+static int add_internal_client(int fd, fd_callback_t callback)
+{
+	struct local_client *client;
+
+	DEBUGLOG("Add_internal_client, fd = %d\n", fd);
+
+	client = malloc(sizeof(struct local_client));
+	if (!client)
+	{
+		DEBUGLOG("malloc failed\n");
+		return -1;
+	}
+
+	memset(client, 0, sizeof(struct local_client));
+	client->fd = fd;
+	client->type = CLUSTER_INTERNAL;
+	client->callback = callback;
+	add_client(client);
+
+	/* Set Close-on-exec */
+	fcntl(fd, F_SETFD, 1);
+
+	return 0;
+}
+
+static void openais_cpg_deliver_callback (cpg_handle_t handle,
+				  const struct cpg_name *groupName,
+				  uint32_t nodeid,
+				  uint32_t pid,
+				  void *msg,
+				  size_t msg_len)
+{
+	int target_nodeid;
+
+	memcpy(&target_nodeid, msg, OPENAIS_CSID_LEN);
+
+	DEBUGLOG("%u got message from nodeid %d for %d. len %" PRIsize_t "\n",
+		 our_nodeid, nodeid, target_nodeid, msg_len-4);
+
+	if (nodeid != our_nodeid)
+		if (target_nodeid == our_nodeid || target_nodeid == 0)
+			process_message(cluster_client, (char *)msg+OPENAIS_CSID_LEN,
+					msg_len-OPENAIS_CSID_LEN, (char*)&nodeid);
+}
+
+static void openais_cpg_confchg_callback(cpg_handle_t handle,
+				 const struct cpg_name *groupName,
+				 const struct cpg_address *member_list, size_t member_list_entries,
+				 const struct cpg_address *left_list, size_t left_list_entries,
+				 const struct cpg_address *joined_list, size_t joined_list_entries)
+{
+	int i;
+	struct node_info *ninfo;
+
+	DEBUGLOG("confchg callback. %" PRIsize_t " joined, "
+		 "%" PRIsize_t " left, %" PRIsize_t " members\n",
+		 joined_list_entries, left_list_entries, member_list_entries);
+
+	for (i=0; i<joined_list_entries; i++) {
+		ninfo = dm_hash_lookup_binary(node_hash,
+					      (char *)&joined_list[i].nodeid,
+					      OPENAIS_CSID_LEN);
+		if (!ninfo) {
+			ninfo = malloc(sizeof(struct node_info));
+			if (!ninfo) {
+				break;
+			}
+			else {
+				ninfo->nodeid = joined_list[i].nodeid;
+				dm_hash_insert_binary(node_hash,
+						      (char *)&ninfo->nodeid,
+						      OPENAIS_CSID_LEN, ninfo);
+			}
+		}
+		ninfo->state = NODE_CLVMD;
+	}
+
+	for (i=0; i<left_list_entries; i++) {
+		ninfo = dm_hash_lookup_binary(node_hash,
+					      (char *)&left_list[i].nodeid,
+					      OPENAIS_CSID_LEN);
+		if (ninfo)
+			ninfo->state = NODE_DOWN;
+	}
+
+	for (i=0; i<member_list_entries; i++) {
+		if (member_list[i].nodeid == 0) continue;
+		ninfo = dm_hash_lookup_binary(node_hash,
+				(char *)&member_list[i].nodeid,
+				OPENAIS_CSID_LEN);
+		if (!ninfo) {
+			ninfo = malloc(sizeof(struct node_info));
+			if (!ninfo) {
+				break;
+			}
+			else {
+				ninfo->nodeid = member_list[i].nodeid;
+				dm_hash_insert_binary(node_hash,
+						(char *)&ninfo->nodeid,
+						OPENAIS_CSID_LEN, ninfo);
+			}
+		}
+		ninfo->state = NODE_CLVMD;
+	}
+
+	num_nodes = member_list_entries;
+}
+
+static int lck_dispatch(struct local_client *client, char *buf, int len,
+			const char *csid, struct local_client **new_client)
+{
+	*new_client = NULL;
+	saLckDispatch(lck_handle, SA_DISPATCH_ONE);
+	return 1;
+}
+
+static int _init_cluster(void)
+{
+	SaAisErrorT err;
+	SaVersionT  ver = { 'B', 1, 1 };
+	int select_fd;
+
+	node_hash = dm_hash_create(100);
+	lock_hash = dm_hash_create(10);
+
+	err = cpg_initialize(&cpg_handle,
+			     &openais_cpg_callbacks);
+	if (err != SA_AIS_OK) {
+		syslog(LOG_ERR, "Cannot initialise OpenAIS CPG service: %d",
+		       err);
+		DEBUGLOG("Cannot initialise OpenAIS CPG service: %d", err);
+		return ais_to_errno(err);
+	}
+
+	err = saLckInitialize(&lck_handle,
+					NULL,
+			      &ver);
+	if (err != SA_AIS_OK) {
+		cpg_initialize(&cpg_handle, &openais_cpg_callbacks);
+		syslog(LOG_ERR, "Cannot initialise OpenAIS lock service: %d",
+		       err);
+		DEBUGLOG("Cannot initialise OpenAIS lock service: %d\n\n", err);
+		return ais_to_errno(err);
+	}
+
+	/* Connect to the clvmd group */
+	strcpy((char *)cpg_group_name.value, "clvmd");
+	cpg_group_name.length = strlen((char *)cpg_group_name.value);
+	err = cpg_join(cpg_handle, &cpg_group_name);
+	if (err != SA_AIS_OK) {
+		cpg_finalize(cpg_handle);
+		saLckFinalize(lck_handle);
+		syslog(LOG_ERR, "Cannot join clvmd process group");
+		DEBUGLOG("Cannot join clvmd process group: %d\n", err);
+		return ais_to_errno(err);
+	}
+
+	err = cpg_local_get(cpg_handle,
+			    &our_nodeid);
+	if (err != SA_AIS_OK) {
+		cpg_finalize(cpg_handle);
+		saLckFinalize(lck_handle);
+		syslog(LOG_ERR, "Cannot get local node id\n");
+		return ais_to_errno(err);
+	}
+	DEBUGLOG("Our local node id is %d\n", our_nodeid);
+
+	saLckSelectionObjectGet(lck_handle, (SaSelectionObjectT *)&select_fd);
+	add_internal_client(select_fd, lck_dispatch);
+
+	DEBUGLOG("Connected to OpenAIS\n");
+
+	return 0;
+}
+
+static void _cluster_closedown(void)
+{
+	DEBUGLOG("cluster_closedown\n");
+	destroy_lvhash();
+
+	saLckFinalize(lck_handle);
+	cpg_finalize(cpg_handle);
+}
+
+static void _get_our_csid(char *csid)
+{
+	memcpy(csid, &our_nodeid, sizeof(int));
+}
+
+/* OpenAIS doesn't really have nmode names so we
+   just use the node ID in hex instead */
+static int _csid_from_name(char *csid, const char *name)
+{
+	int nodeid;
+	struct node_info *ninfo;
+
+	if (sscanf(name, "%x", &nodeid) == 1) {
+		ninfo = dm_hash_lookup_binary(node_hash, csid, OPENAIS_CSID_LEN);
+		if (ninfo)
+			return nodeid;
+	}
+	return -1;
+}
+
+static int _name_from_csid(const char *csid, char *name)
+{
+	struct node_info *ninfo;
+
+	ninfo = dm_hash_lookup_binary(node_hash, csid, OPENAIS_CSID_LEN);
+	if (!ninfo)
+	{
+		sprintf(name, "UNKNOWN %s", print_openais_csid(csid));
+		return -1;
+	}
+
+	sprintf(name, "%x", ninfo->nodeid);
+	return 0;
+}
+
+static int _get_num_nodes()
+{
+	DEBUGLOG("num_nodes = %d\n", num_nodes);
+	return num_nodes;
+}
+
+/* Node is now known to be running a clvmd */
+static void _add_up_node(const char *csid)
+{
+	struct node_info *ninfo;
+
+	ninfo = dm_hash_lookup_binary(node_hash, csid, OPENAIS_CSID_LEN);
+	if (!ninfo) {
+		DEBUGLOG("openais_add_up_node no node_hash entry for csid %s\n",
+			 print_openais_csid(csid));
+		return;
+	}
+
+	DEBUGLOG("openais_add_up_node %d\n", ninfo->nodeid);
+
+	ninfo->state = NODE_CLVMD;
+
+	return;
+}
+
+/* Call a callback for each node, so the caller knows whether it's up or down */
+static int _cluster_do_node_callback(struct local_client *master_client,
+				     void (*callback)(struct local_client *,
+						      const char *csid, int node_up))
+{
+	struct dm_hash_node *hn;
+	struct node_info *ninfo;
+	int somedown = 0;
+
+	dm_hash_iterate(hn, node_hash)
+	{
+		char csid[OPENAIS_CSID_LEN];
+
+		ninfo = dm_hash_get_data(node_hash, hn);
+		memcpy(csid, dm_hash_get_key(node_hash, hn), OPENAIS_CSID_LEN);
+
+		DEBUGLOG("down_callback. node %d, state = %d\n", ninfo->nodeid,
+			 ninfo->state);
+
+		if (ninfo->state != NODE_DOWN)
+			callback(master_client, csid, ninfo->state == NODE_CLVMD);
+		if (ninfo->state != NODE_CLVMD)
+			somedown = -1;
+	}
+	return somedown;
+}
+
+/* Real locking */
+static int _lock_resource(char *resource, int mode, int flags, int *lockid)
+{
+	struct lock_info *linfo;
+	SaLckResourceHandleT res_handle;
+	SaAisErrorT err;
+	SaLckLockIdT lock_id;
+	SaLckLockStatusT lockStatus;
+
+	/* This needs to be converted from DLM/LVM2 value for OpenAIS LCK */
+	if (flags & LCK_NONBLOCK) flags = SA_LCK_LOCK_NO_QUEUE;
+
+	linfo = malloc(sizeof(struct lock_info));
+	if (!linfo)
+		return -1;
+
+	DEBUGLOG("lock_resource '%s', flags=%d, mode=%d\n", resource, flags, mode);
+
+	linfo->lock_name.length = strlen(resource)+1;
+	strcpy((char *)linfo->lock_name.value, resource);
+
+	err = saLckResourceOpen(lck_handle, &linfo->lock_name,
+				SA_LCK_RESOURCE_CREATE, TIMEOUT, &res_handle);
+	if (err != SA_AIS_OK)
+	{
+		DEBUGLOG("ResourceOpen returned %d\n", err);
+		free(linfo);
+		return ais_to_errno(err);
+	}
+
+	err = saLckResourceLock(
+			res_handle,
+			&lock_id,
+			mode,
+			flags,
+			0,
+			SA_TIME_END,
+			&lockStatus);
+	if (err != SA_AIS_OK && lockStatus != SA_LCK_LOCK_GRANTED)
+	{
+		free(linfo);
+		saLckResourceClose(res_handle);
+		return ais_to_errno(err);
+	}
+			
+	/* Wait for it to complete */
+
+	DEBUGLOG("lock_resource returning %d, lock_id=%" PRIx64 "\n",
+		 err, lock_id);
+
+	linfo->lock_id = lock_id;
+	linfo->res_handle = res_handle;
+
+	dm_hash_insert(lock_hash, resource, linfo);
+
+	return ais_to_errno(err);
+}
+
+
+static int _unlock_resource(char *resource, int lockid)
+{
+	SaAisErrorT err;
+	struct lock_info *linfo;
+
+	DEBUGLOG("unlock_resource %s\n", resource);
+	linfo = dm_hash_lookup(lock_hash, resource);
+	if (!linfo)
+		return 0;
+
+	DEBUGLOG("unlock_resource: lockid: %" PRIx64 "\n", linfo->lock_id);
+	err = saLckResourceUnlock(linfo->lock_id, SA_TIME_END);
+	if (err != SA_AIS_OK)
+	{
+		DEBUGLOG("Unlock returned %d\n", err);
+		return ais_to_errno(err);
+	}
+
+	/* Release the resource */
+	dm_hash_remove(lock_hash, resource);
+	saLckResourceClose(linfo->res_handle);
+	free(linfo);
+
+	return ais_to_errno(err);
+}
+
+static int _sync_lock(const char *resource, int mode, int flags, int *lockid)
+{
+	int status;
+	char lock1[strlen(resource)+3];
+	char lock2[strlen(resource)+3];
+
+	snprintf(lock1, sizeof(lock1), "%s-1", resource);
+	snprintf(lock2, sizeof(lock2), "%s-2", resource);
+
+	switch (mode)
+	{
+	case LCK_EXCL:
+		status = _lock_resource(lock1, SA_LCK_EX_LOCK_MODE, flags, lockid);
+		if (status)
+			goto out;
+
+		/* If we can't get this lock too then bail out */
+		status = _lock_resource(lock2, SA_LCK_EX_LOCK_MODE, LCK_NONBLOCK,
+					lockid);
+		if (status == SA_LCK_LOCK_NOT_QUEUED)
+		{
+			_unlock_resource(lock1, *lockid);
+			status = -1;
+			errno = EAGAIN;
+		}
+		break;
+
+	case LCK_PREAD:
+	case LCK_READ:
+		status = _lock_resource(lock1, SA_LCK_PR_LOCK_MODE, flags, lockid);
+		if (status)
+			goto out;
+		_unlock_resource(lock2, *lockid);
+		break;
+
+	case LCK_WRITE:
+		status = _lock_resource(lock2, SA_LCK_EX_LOCK_MODE, flags, lockid);
+		if (status)
+			goto out;
+		_unlock_resource(lock1, *lockid);
+		break;
+
+	default:
+		status = -1;
+		errno = EINVAL;
+		break;
+	}
+out:
+	*lockid = mode;
+	return status;
+}
+
+static int _sync_unlock(const char *resource, int lockid)
+{
+	int status = 0;
+	char lock1[strlen(resource)+3];
+	char lock2[strlen(resource)+3];
+
+	snprintf(lock1, sizeof(lock1), "%s-1", resource);
+	snprintf(lock2, sizeof(lock2), "%s-2", resource);
+
+	_unlock_resource(lock1, lockid);
+	_unlock_resource(lock2, lockid);
+
+	return status;
+}
+
+/* We are always quorate ! */
+static int _is_quorate()
+{
+	return 1;
+}
+
+static int _get_main_cluster_fd(void)
+{
+	int select_fd;
+
+	cpg_fd_get(cpg_handle, &select_fd);
+	return select_fd;
+}
+
+static int _cluster_fd_callback(struct local_client *fd, char *buf, int len,
+				const char *csid,
+				struct local_client **new_client)
+{
+	cluster_client = fd;
+	*new_client = NULL;
+	cpg_dispatch(cpg_handle, SA_DISPATCH_ONE);
+	return 1;
+}
+
+static int _cluster_send_message(const void *buf, int msglen, const char *csid,
+				 const char *errtext)
+{
+	struct iovec iov[2];
+	SaAisErrorT err;
+	int target_node;
+
+	if (csid)
+		memcpy(&target_node, csid, OPENAIS_CSID_LEN);
+	else
+		target_node = 0;
+
+	iov[0].iov_base = &target_node;
+	iov[0].iov_len = sizeof(int);
+	iov[1].iov_base = (char *)buf;
+	iov[1].iov_len = msglen;
+
+	err = cpg_mcast_joined(cpg_handle, CPG_TYPE_AGREED, iov, 2);
+	return ais_to_errno(err);
+}
+
+/* We don't have a cluster name to report here */
+static int _get_cluster_name(char *buf, int buflen)
+{
+	strncpy(buf, "OpenAIS", buflen);
+	return 0;
+}
+
+static struct cluster_ops _cluster_openais_ops = {
+	.name                     = "openais",
+	.cluster_init_completed   = NULL,
+	.cluster_send_message     = _cluster_send_message,
+	.name_from_csid           = _name_from_csid,
+	.csid_from_name           = _csid_from_name,
+	.get_num_nodes            = _get_num_nodes,
+	.cluster_fd_callback      = _cluster_fd_callback,
+	.get_main_cluster_fd      = _get_main_cluster_fd,
+	.cluster_do_node_callback = _cluster_do_node_callback,
+	.is_quorate               = _is_quorate,
+	.get_our_csid             = _get_our_csid,
+	.add_up_node              = _add_up_node,
+	.reread_config            = NULL,
+	.cluster_closedown        = _cluster_closedown,
+	.get_cluster_name         = _get_cluster_name,
+	.sync_lock                = _sync_lock,
+	.sync_unlock              = _sync_unlock,
+};
+
+struct cluster_ops *init_openais_cluster(void)
+{
+	if (!_init_cluster())
+		return &_cluster_openais_ops;
+	else
+		return NULL;
+}

daemons/clvmd/clvmd-singlenode.c

@@ -0,0 +1,321 @@
+/*
+ * Copyright (C) 2009 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "clvmd-common.h"
+
+#include <pthread.h>
+
+#include "locking.h"
+#include "clvm.h"
+#include "clvmd-comms.h"
+#include "lvm-functions.h"
+#include "clvmd.h"
+
+#include <sys/un.h>
+#include <sys/socket.h>
+#include <fcntl.h>
+
+static const char SINGLENODE_CLVMD_SOCKNAME[] = DEFAULT_RUN_DIR "/clvmd_singlenode.sock";
+static int listen_fd = -1;
+static int *_locks = NULL;
+static char **_resources = NULL;
+
+static void close_comms(void)
+{
+	if (listen_fd != -1 && close(listen_fd))
+		stack;
+	(void)unlink(SINGLENODE_CLVMD_SOCKNAME);
+	listen_fd = -1;
+}
+
+static int init_comms(void)
+{
+	struct sockaddr_un addr;
+	mode_t old_mask;
+
+	close_comms();
+
+	(void) dm_prepare_selinux_context(SINGLENODE_CLVMD_SOCKNAME, S_IFSOCK);
+	old_mask = umask(0077);
+
+	listen_fd = socket(PF_UNIX, SOCK_STREAM, 0);
+	if (listen_fd < 0) {
+		DEBUGLOG("Can't create local socket: %s\n", strerror(errno));
+		goto error;
+	}
+	/* Set Close-on-exec */
+	if (fcntl(listen_fd, F_SETFD, 1)) {
+		DEBUGLOG("Setting CLOEXEC on client fd failed: %s\n", strerror(errno));
+		goto error;
+	}
+
+	memset(&addr, 0, sizeof(addr));
+	memcpy(addr.sun_path, SINGLENODE_CLVMD_SOCKNAME,
+	       sizeof(SINGLENODE_CLVMD_SOCKNAME));
+	addr.sun_family = AF_UNIX;
+
+	if (bind(listen_fd, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
+		DEBUGLOG("Can't bind local socket: %s\n", strerror(errno));
+		goto error;
+	}
+	if (listen(listen_fd, 10) < 0) {
+		DEBUGLOG("Can't listen local socket: %s\n", strerror(errno));
+		goto error;
+	}
+
+	umask(old_mask);
+	(void) dm_prepare_selinux_context(NULL, 0);
+	return 0;
+error:
+	umask(old_mask);
+	(void) dm_prepare_selinux_context(NULL, 0);
+	close_comms();
+	return -1;
+}
+
+static int _init_cluster(void)
+{
+	int r;
+
+	r = init_comms();
+	if (r)
+		return r;
+
+	DEBUGLOG("Single-node cluster initialised.\n");
+	return 0;
+}
+
+static void _cluster_closedown(void)
+{
+	close_comms();
+
+	DEBUGLOG("cluster_closedown\n");
+	destroy_lvhash();
+	dm_free(_locks);
+	dm_free(_resources);
+	_locks = NULL;
+	_resources = NULL;
+}
+
+static void _get_our_csid(char *csid)
+{
+	int nodeid = 1;
+	memcpy(csid, &nodeid, sizeof(int));
+}
+
+static int _csid_from_name(char *csid, const char *name)
+{
+	return 1;
+}
+
+static int _name_from_csid(const char *csid, char *name)
+{
+	sprintf(name, "SINGLENODE");
+	return 0;
+}
+
+static int _get_num_nodes(void)
+{
+	return 1;
+}
+
+/* Node is now known to be running a clvmd */
+static void _add_up_node(const char *csid)
+{
+}
+
+/* Call a callback for each node, so the caller knows whether it's up or down */
+static int _cluster_do_node_callback(struct local_client *master_client,
+				     void (*callback)(struct local_client *,
+				     const char *csid, int node_up))
+{
+	return 0;
+}
+
+int _lock_file(const char *file, uint32_t flags);
+
+static int _lock_max = 1;
+static pthread_mutex_t _lock_mutex = PTHREAD_MUTEX_INITIALIZER;
+/* Using one common condition for all locks for simplicity */
+static pthread_cond_t _lock_cond = PTHREAD_COND_INITIALIZER;
+
+/* Real locking */
+static int _lock_resource(const char *resource, int mode, int flags, int *lockid)
+{
+	int *_locks_1;
+	char **_resources_1;
+	int i, j;
+
+	if (mode == LCK_READ) { /* only track PREAD, aka PROTECTED READ */
+		DEBUGLOG("Not tracking CONCURRENT READ lock: %s, flags=%d, mode=%d\n",
+			 resource, flags, mode);
+		*lockid = -1;
+		return 0;
+	}
+
+	DEBUGLOG("Locking resource %s, flags=%d, mode=%d\n",
+		 resource, flags, mode);
+
+	pthread_mutex_lock(&_lock_mutex);
+retry:
+
+	/* look for an existing lock for this resource */
+	for (i = 1; i < _lock_max; ++i) {
+		if (!_resources[i])
+			break;
+		if (!strcmp(_resources[i], resource)) {
+			if ((_locks[i] & LCK_TYPE_MASK) == LCK_WRITE ||
+			    (_locks[i] & LCK_TYPE_MASK) == LCK_EXCL) {
+				DEBUGLOG("Resource %s already write/exclusively locked...\n", resource);
+				goto maybe_retry;
+			}
+			if ((mode & LCK_TYPE_MASK) == LCK_WRITE ||
+			    (mode & LCK_TYPE_MASK) == LCK_EXCL) {
+				DEBUGLOG("Resource %s already locked and WRITE/EXCL lock requested...\n",
+					 resource);
+				goto maybe_retry;
+			}
+		}
+	}
+
+	if (i == _lock_max) { /* out of lock slots, extend */
+		if (!(_locks_1 = dm_realloc(_locks, 2 * _lock_max * sizeof(int))))
+			goto_bad;
+
+		_locks = _locks_1;
+		if (!(_resources_1 = dm_realloc(_resources, 2 * _lock_max * sizeof(char *))))
+			/* _locks may get realloc'd twice, but that should be safe */
+			goto_bad;
+
+		_resources = _resources_1;
+		/* clear the new resource entries */
+		for (j = _lock_max; j < 2 * _lock_max; ++j)
+			_resources[j] = NULL;
+		_lock_max = 2 * _lock_max;
+	}
+
+	/* resource is not currently locked, grab it */
+	if (!(_resources[i] = dm_strdup(resource)))
+		goto_bad;
+
+	*lockid = i;
+	_locks[i] = mode;
+
+	DEBUGLOG("Locked resource %s, lockid=%d\n", resource, i);
+	pthread_mutex_unlock(&_lock_mutex);
+
+	return 0;
+
+maybe_retry:
+	if (!(flags & LCK_NONBLOCK)) {
+		pthread_cond_wait(&_lock_cond, &_lock_mutex);
+		goto retry;
+	}
+bad:
+	DEBUGLOG("Failed to lock resource %s\n", resource);
+	pthread_mutex_unlock(&_lock_mutex);
+
+	return 1; /* fail */
+}
+
+static int _unlock_resource(const char *resource, int lockid)
+{
+	if (lockid < 0) {
+		DEBUGLOG("Not tracking unlock of lockid -1: %s, lockid=%d\n",
+			 resource, lockid);
+		return 0;
+	}
+
+	DEBUGLOG("Unlocking resource %s, lockid=%d\n", resource, lockid);
+	pthread_mutex_lock(&_lock_mutex);
+
+	if (!_resources[lockid]) {
+		pthread_mutex_unlock(&_lock_mutex);
+		DEBUGLOG("Resource %s, lockid=%d is not locked\n", resource, lockid);
+		return 1;
+	}
+
+	if (strcmp(_resources[lockid], resource)) {
+		pthread_mutex_unlock(&_lock_mutex);
+		DEBUGLOG("Resource %d has wrong resource (requested %s, got %s)\n",
+			 lockid, resource, _resources[lockid]);
+		return 1;
+	}
+
+	dm_free(_resources[lockid]);
+	_resources[lockid] = 0;
+	pthread_cond_broadcast(&_lock_cond); /* wakeup waiters */
+	pthread_mutex_unlock(&_lock_mutex);
+
+	return 0;
+}
+
+static int _is_quorate(void)
+{
+	return 1;
+}
+
+static int _get_main_cluster_fd(void)
+{
+	return listen_fd;
+}
+
+static int _cluster_fd_callback(struct local_client *fd, char *buf, int len,
+				const char *csid,
+				struct local_client **new_client)
+{
+	return 1;
+}
+
+static int _cluster_send_message(const void *buf, int msglen,
+				 const char *csid,
+				 const char *errtext)
+{
+	return 0;
+}
+
+static int _get_cluster_name(char *buf, int buflen)
+{
+	strncpy(buf, "localcluster", buflen);
+	buf[buflen - 1] = 0;
+	return 0;
+}
+
+static struct cluster_ops _cluster_singlenode_ops = {
+	.name                     = "singlenode",
+	.cluster_init_completed   = NULL,
+	.cluster_send_message     = _cluster_send_message,
+	.name_from_csid           = _name_from_csid,
+	.csid_from_name           = _csid_from_name,
+	.get_num_nodes            = _get_num_nodes,
+	.cluster_fd_callback      = _cluster_fd_callback,
+	.get_main_cluster_fd      = _get_main_cluster_fd,
+	.cluster_do_node_callback = _cluster_do_node_callback,
+	.is_quorate               = _is_quorate,
+	.get_our_csid             = _get_our_csid,
+	.add_up_node              = _add_up_node,
+	.reread_config            = NULL,
+	.cluster_closedown        = _cluster_closedown,
+	.get_cluster_name         = _get_cluster_name,
+	.sync_lock                = _lock_resource,
+	.sync_unlock              = _unlock_resource,
+};
+
+struct cluster_ops *init_singlenode_cluster(void)
+{
+	if (!_init_cluster())
+		return &_cluster_singlenode_ops;
+	else
+		return NULL;
+}

daemons/clvmd/clvmd.h

@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2002-2004 Sistina Software, Inc. All rights reserved.
+ * Copyright (C) 2004 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _CLVMD_H
+#define _CLVMD_H
+
+#define CLVMD_MAJOR_VERSION 0
+#define CLVMD_MINOR_VERSION 2
+#define CLVMD_PATCH_VERSION 1
+
+/* Default time (in seconds) we will wait for all remote commands to execute
+   before declaring them dead */
+#define DEFAULT_CMD_TIMEOUT 60
+
+/* One of these for each reply we get from command execution on a node */
+struct node_reply {
+	char node[MAX_CLUSTER_MEMBER_NAME_LEN];
+	char *replymsg;
+	int status;
+	struct node_reply *next;
+};
+
+typedef enum {DEBUG_OFF, DEBUG_STDERR, DEBUG_SYSLOG} debug_t;
+
+/*
+ * These exist for the use of local sockets only when we are
+ * collecting responses from all cluster nodes
+ */
+struct localsock_bits {
+	struct node_reply *replies;
+	int num_replies;
+	int expected_replies;
+	time_t sent_time;	/* So we can check for timeouts */
+	int in_progress;	/* Only execute one cmd at a time per client */
+	int sent_out;		/* Flag to indicate that a command was sent
+				   to remote nodes */
+	void *private;		/* Private area for command processor use */
+	void *cmd;		/* Whole command as passed down local socket */
+	int cmd_len;		/* Length of above */
+	int pipe;		/* Pipe to send PRE completion status down */
+	int finished;		/* Flag to tell subthread to exit */
+	int all_success;	/* Set to 0 if any node (or the pre_command)
+				   failed */
+	struct local_client *pipe_client;
+	pthread_t threadid;
+	enum { PRE_COMMAND, POST_COMMAND, QUIT } state;
+	pthread_mutex_t mutex;	/* Main thread and worker synchronisation */
+	pthread_cond_t cond;
+
+	pthread_mutex_t reply_mutex;	/* Protect reply structure */
+};
+
+/* Entries for PIPE clients */
+struct pipe_bits {
+	struct local_client *client;	/* Actual (localsock) client */
+	pthread_t threadid;		/* Our own copy of the thread id */
+};
+
+/* Entries for Network socket clients */
+struct netsock_bits {
+	void *private;
+	int flags;
+};
+
+typedef int (*fd_callback_t) (struct local_client * fd, char *buf, int len,
+			      const char *csid,
+			      struct local_client ** new_client);
+
+/* One of these for each fd we are listening on */
+struct local_client {
+	int fd;
+	enum { CLUSTER_MAIN_SOCK, CLUSTER_DATA_SOCK, LOCAL_RENDEZVOUS,
+		    LOCAL_SOCK, THREAD_PIPE, CLUSTER_INTERNAL } type;
+	struct local_client *next;
+	unsigned short xid;
+	fd_callback_t callback;
+	uint8_t removeme;
+
+	union {
+		struct localsock_bits localsock;
+		struct pipe_bits pipe;
+		struct netsock_bits net;
+	} bits;
+};
+
+#define DEBUGLOG(fmt, args...) debuglog(fmt, ## args);
+
+#ifndef max
+#define max(a,b) ((a)>(b)?(a):(b))
+#endif
+
+/* The real command processor is in clvmd-command.c */
+extern int do_command(struct local_client *client, struct clvm_header *msg,
+		      int msglen, char **buf, int buflen, int *retlen);
+
+/* Pre and post command routines are called only on the local node */
+extern int do_pre_command(struct local_client *client);
+extern int do_post_command(struct local_client *client);
+extern void cmd_client_cleanup(struct local_client *client);
+extern int add_client(struct local_client *new_client);
+
+extern void clvmd_cluster_init_completed(void);
+extern void process_message(struct local_client *client, char *buf,
+			    int len, const char *csid);
+extern void debuglog(const char *fmt, ... )
+  __attribute__ ((format(printf, 1, 2)));
+
+void clvmd_set_debug(debug_t new_de);
+debug_t clvmd_get_debug(void);
+
+int sync_lock(const char *resource, int mode, int flags, int *lockid);
+int sync_unlock(const char *resource, int lockid);
+
+#endif

daemons/clvmd/lvm-functions.c

@@ -0,0 +1,917 @@
+/*
+ * Copyright (C) 2002-2004 Sistina Software, Inc. All rights reserved.
+ * Copyright (C) 2004-2011 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "clvmd-common.h"
+
+#include <pthread.h>
+
+#include "lvm-types.h"
+#include "clvm.h"
+#include "clvmd-comms.h"
+#include "clvmd.h"
+#include "lvm-functions.h"
+
+/* LVM2 headers */
+#include "toolcontext.h"
+#include "lvmcache.h"
+#include "lvm-globals.h"
+#include "activate.h"
+#include "archiver.h"
+#include "memlock.h"
+
+#include <syslog.h>
+
+static struct cmd_context *cmd = NULL;
+static struct dm_hash_table *lv_hash = NULL;
+static pthread_mutex_t lv_hash_lock;
+static pthread_mutex_t lvm_lock;
+static char last_error[1024];
+
+struct lv_info {
+	int lock_id;
+	int lock_mode;
+};
+
+static const char *decode_full_locking_cmd(uint32_t cmdl)
+{
+	static char buf[128];
+	const char *type;
+	const char *scope;
+	const char *command;
+
+	switch (cmdl & LCK_TYPE_MASK) {
+	case LCK_NULL:
+		type = "NULL";
+		break;
+	case LCK_READ:
+		type = "READ";
+		break;
+	case LCK_PREAD:
+		type = "PREAD";
+		break;
+	case LCK_WRITE:
+		type = "WRITE";
+		break;
+	case LCK_EXCL:
+		type = "EXCL";
+		break;
+	case LCK_UNLOCK:
+		type = "UNLOCK";
+		break;
+	default:
+		type = "unknown";
+		break;
+	}
+
+	switch (cmdl & LCK_SCOPE_MASK) {
+	case LCK_VG:
+		scope = "VG";
+		command = "LCK_VG";
+		break;
+	case LCK_LV:
+		scope = "LV";
+		switch (cmdl & LCK_MASK) {
+		case LCK_LV_EXCLUSIVE & LCK_MASK:
+			command = "LCK_LV_EXCLUSIVE";
+			break;
+		case LCK_LV_SUSPEND & LCK_MASK:
+			command = "LCK_LV_SUSPEND";
+			break;
+		case LCK_LV_RESUME & LCK_MASK:
+			command = "LCK_LV_RESUME";
+			break;
+		case LCK_LV_ACTIVATE & LCK_MASK:
+			command = "LCK_LV_ACTIVATE";
+			break;
+		case LCK_LV_DEACTIVATE & LCK_MASK:
+			command = "LCK_LV_DEACTIVATE";
+			break;
+		default:
+			command = "unknown";
+			break;
+		}
+		break;
+	default:
+		scope = "unknown";
+		command = "unknown";
+		break;
+	}
+
+	sprintf(buf, "0x%x %s (%s|%s%s%s%s%s)", cmdl, command, type, scope,
+		cmdl & LCK_NONBLOCK   ? "|NONBLOCK" : "",
+		cmdl & LCK_HOLD       ? "|HOLD" : "",
+		cmdl & LCK_CLUSTER_VG ? "|CLUSTER_VG" : "",
+		cmdl & LCK_CACHE      ? "|CACHE" : "");
+
+	return buf;
+}
+
+/*
+ * Only processes 8 bits: excludes LCK_CACHE.
+ */
+static const char *decode_locking_cmd(unsigned char cmdl)
+{
+	return decode_full_locking_cmd((uint32_t) cmdl);
+}
+
+static const char *decode_flags(unsigned char flags)
+{
+	static char buf[128];
+	int len;
+
+	len = sprintf(buf, "0x%x ( %s%s%s%s%s%s%s)", flags,
+		flags & LCK_PARTIAL_MODE	  ? "PARTIAL_MODE|" : "",
+		flags & LCK_MIRROR_NOSYNC_MODE	  ? "MIRROR_NOSYNC|" : "",
+		flags & LCK_DMEVENTD_MONITOR_MODE ? "DMEVENTD_MONITOR|" : "",
+		flags & LCK_ORIGIN_ONLY_MODE ? "ORIGIN_ONLY|" : "",
+		flags & LCK_TEST_MODE ? "TEST|" : "",
+		flags & LCK_CONVERT ? "CONVERT|" : "",
+		flags & LCK_DMEVENTD_MONITOR_IGNORE ? "DMEVENTD_MONITOR_IGNORE|" : "");
+
+	if (len > 1)
+		buf[len - 2] = ' ';
+	else
+		buf[0] = '\0';
+
+	return buf;
+}
+
+char *get_last_lvm_error(void)
+{
+	return last_error;
+}
+
+/*
+ * Hash lock info helpers
+ */
+static struct lv_info *lookup_info(const char *resource)
+{
+	struct lv_info *lvi;
+
+	pthread_mutex_lock(&lv_hash_lock);
+	lvi = dm_hash_lookup(lv_hash, resource);
+	pthread_mutex_unlock(&lv_hash_lock);
+
+	return lvi;
+}
+
+static void insert_info(const char *resource, struct lv_info *lvi)
+{
+	pthread_mutex_lock(&lv_hash_lock);
+	dm_hash_insert(lv_hash, resource, lvi);
+	pthread_mutex_unlock(&lv_hash_lock);
+}
+
+static void remove_info(const char *resource)
+{
+	pthread_mutex_lock(&lv_hash_lock);
+	dm_hash_remove(lv_hash, resource);
+	pthread_mutex_unlock(&lv_hash_lock);
+}
+
+/*
+ * Return the mode a lock is currently held at (or -1 if not held)
+ */
+static int get_current_lock(char *resource)
+{
+	struct lv_info *lvi;
+
+	if ((lvi = lookup_info(resource)))
+		return lvi->lock_mode;
+
+	return -1;
+}
+
+
+void init_lvhash(void)
+{
+	/* Create hash table for keeping LV locks & status */
+	lv_hash = dm_hash_create(1024);
+	pthread_mutex_init(&lv_hash_lock, NULL);
+	pthread_mutex_init(&lvm_lock, NULL);
+}
+
+/* Called at shutdown to tidy the lockspace */
+void destroy_lvhash(void)
+{
+	struct dm_hash_node *v;
+	struct lv_info *lvi;
+	char *resource;
+	int status;
+
+	pthread_mutex_lock(&lv_hash_lock);
+
+	dm_hash_iterate(v, lv_hash) {
+		lvi = dm_hash_get_data(lv_hash, v);
+		resource = dm_hash_get_key(lv_hash, v);
+
+		if ((status = sync_unlock(resource, lvi->lock_id)))
+			DEBUGLOG("unlock_all. unlock failed(%d): %s\n",
+				 status,  strerror(errno));
+		free(lvi);
+	}
+
+	dm_hash_destroy(lv_hash);
+	lv_hash = NULL;
+
+	pthread_mutex_unlock(&lv_hash_lock);
+}
+
+/* Gets a real lock and keeps the info in the hash table */
+static int hold_lock(char *resource, int mode, int flags)
+{
+	int status;
+	int saved_errno;
+	struct lv_info *lvi;
+
+	if (test_mode())
+		return 0;
+
+	/* Mask off invalid options */
+	flags &= LCKF_NOQUEUE | LCKF_CONVERT;
+
+	lvi = lookup_info(resource);
+
+	if (lvi) {
+		if (lvi->lock_mode == mode) {
+			DEBUGLOG("hold_lock, lock mode %d already held\n",
+				 mode);
+			return 0;
+		}
+		if ((lvi->lock_mode == LCK_EXCL) && (mode == LCK_WRITE)) {
+			DEBUGLOG("hold_lock, lock already held LCK_EXCL, "
+				 "ignoring LCK_WRITE request");
+			return 0;
+		}
+	}
+
+	/* Only allow explicit conversions */
+	if (lvi && !(flags & LCKF_CONVERT)) {
+		errno = EBUSY;
+		return -1;
+	}
+	if (lvi) {
+		/* Already exists - convert it */
+		status =
+		    sync_lock(resource, mode, flags, &lvi->lock_id);
+		saved_errno = errno;
+		if (!status)
+			lvi->lock_mode = mode;
+
+		if (status) {
+			DEBUGLOG("hold_lock. convert to %d failed: %s\n", mode,
+				 strerror(errno));
+		}
+		errno = saved_errno;
+	} else {
+		lvi = malloc(sizeof(struct lv_info));
+		if (!lvi)
+			return -1;
+
+		lvi->lock_mode = mode;
+		status = sync_lock(resource, mode, flags & ~LCKF_CONVERT, &lvi->lock_id);
+		saved_errno = errno;
+		if (status) {
+			free(lvi);
+			DEBUGLOG("hold_lock. lock at %d failed: %s\n", mode,
+				 strerror(errno));
+		} else
+			insert_info(resource, lvi);
+
+		errno = saved_errno;
+	}
+	return status;
+}
+
+/* Unlock and remove it from the hash table */
+static int hold_unlock(char *resource)
+{
+	struct lv_info *lvi;
+	int status;
+	int saved_errno;
+
+	if (test_mode())
+		return 0;
+
+	if (!(lvi = lookup_info(resource))) {
+		DEBUGLOG("hold_unlock, lock not already held\n");
+		return 0;
+	}
+
+	status = sync_unlock(resource, lvi->lock_id);
+	saved_errno = errno;
+	if (!status) {
+		remove_info(resource);
+		free(lvi);
+	} else {
+		DEBUGLOG("hold_unlock. unlock failed(%d): %s\n", status,
+			 strerror(errno));
+	}
+
+	errno = saved_errno;
+	return status;
+}
+
+/* Watch the return codes here.
+   liblvm API functions return 1(true) for success, 0(false) for failure and don't set errno.
+   libdlm API functions return 0 for success, -1 for failure and do set errno.
+   These functions here return 0 for success or >0 for failure (where the retcode is errno)
+*/
+
+/* Activate LV exclusive or non-exclusive */
+static int do_activate_lv(char *resource, unsigned char command, unsigned char lock_flags, int mode)
+{
+	int oldmode;
+	int status;
+	int activate_lv;
+	int exclusive = 0;
+	struct lvinfo lvi;
+
+	/* Is it already open ? */
+	oldmode = get_current_lock(resource);
+	if (oldmode == mode && (command & LCK_CLUSTER_VG)) {
+		DEBUGLOG("do_activate_lv, lock already held at %d\n", oldmode);
+		return 0;	/* Nothing to do */
+	}
+
+	/* Does the config file want us to activate this LV ? */
+	if (!lv_activation_filter(cmd, resource, &activate_lv))
+		return EIO;
+
+	if (!activate_lv)
+		return 0;	/* Success, we did nothing! */
+
+	/* Do we need to activate exclusively? */
+	if ((activate_lv == 2) || (mode == LCK_EXCL)) {
+		exclusive = 1;
+		mode = LCK_EXCL;
+	}
+
+	/*
+	 * Try to get the lock if it's a clustered volume group.
+	 * Use lock conversion only if requested, to prevent implicit conversion
+	 * of exclusive lock to shared one during activation.
+	 */
+	if (command & LCK_CLUSTER_VG) {
+		status = hold_lock(resource, mode, LCKF_NOQUEUE | (lock_flags & LCK_CONVERT ? LCKF_CONVERT:0));
+		if (status) {
+			/* Return an LVM-sensible error for this.
+			 * Forcing EIO makes the upper level return this text
+			 * rather than the strerror text for EAGAIN.
+			 */
+			if (errno == EAGAIN) {
+				sprintf(last_error, "Volume is busy on another node");
+				errno = EIO;
+			}
+			return errno;
+		}
+	}
+
+	/* If it's suspended then resume it */
+	if (!lv_info_by_lvid(cmd, resource, 0, &lvi, 0, 0))
+		goto error;
+
+	if (lvi.suspended) {
+		critical_section_inc(cmd, "resuming");
+		if (!lv_resume(cmd, resource, 0)) {
+			critical_section_dec(cmd, "resumed");
+			goto error;
+		}
+	}
+
+	/* Now activate it */
+	if (!lv_activate(cmd, resource, exclusive))
+		goto error;
+
+	return 0;
+
+error:
+	if (oldmode == -1 || oldmode != mode)
+		(void)hold_unlock(resource);
+	return EIO;
+}
+
+/* Resume the LV if it was active */
+static int do_resume_lv(char *resource, unsigned char command, unsigned char lock_flags)
+{
+	int oldmode, origin_only, exclusive, revert;
+
+	/* Is it open ? */
+	oldmode = get_current_lock(resource);
+	if (oldmode == -1 && (command & LCK_CLUSTER_VG)) {
+		DEBUGLOG("do_resume_lv, lock not already held\n");
+		return 0;	/* We don't need to do anything */
+	}
+	origin_only = (lock_flags & LCK_ORIGIN_ONLY_MODE) ? 1 : 0;
+	exclusive = (oldmode == LCK_EXCL) ? 1 : 0;
+	revert = (lock_flags & LCK_REVERT_MODE) ? 1 : 0;
+
+	if (!lv_resume_if_active(cmd, resource, origin_only, exclusive, revert))
+		return EIO;
+
+	return 0;
+}
+
+/* Suspend the device if active */
+static int do_suspend_lv(char *resource, unsigned char command, unsigned char lock_flags)
+{
+	int oldmode;
+	struct lvinfo lvi;
+	unsigned origin_only = (lock_flags & LCK_ORIGIN_ONLY_MODE) ? 1 : 0;
+	unsigned exclusive;
+
+	/* Is it open ? */
+	oldmode = get_current_lock(resource);
+	if (oldmode == -1 && (command & LCK_CLUSTER_VG)) {
+		DEBUGLOG("do_suspend_lv, lock not already held\n");
+		return 0; /* Not active, so it's OK */
+	}
+
+	exclusive = (oldmode == LCK_EXCL) ? 1 : 0;
+
+	/* Only suspend it if it exists */
+	if (!lv_info_by_lvid(cmd, resource, origin_only, &lvi, 0, 0))
+		return EIO;
+
+	if (lvi.exists &&
+	    !lv_suspend_if_active(cmd, resource, origin_only, exclusive))
+		return EIO;
+
+	return 0;
+}
+
+static int do_deactivate_lv(char *resource, unsigned char command, unsigned char lock_flags)
+{
+	int oldmode;
+	int status;
+
+	/* Is it open ? */
+	oldmode = get_current_lock(resource);
+	if (oldmode == -1 && (command & LCK_CLUSTER_VG)) {
+		DEBUGLOG("do_deactivate_lock, lock not already held\n");
+		return 0;	/* We don't need to do anything */
+	}
+
+	if (!lv_deactivate(cmd, resource))
+		return EIO;
+
+	if (command & LCK_CLUSTER_VG) {
+		status = hold_unlock(resource);
+		if (status)
+			return errno;
+	}
+
+	return 0;
+}
+
+const char *do_lock_query(char *resource)
+{
+	int mode;
+	const char *type = NULL;
+
+	mode = get_current_lock(resource);
+	switch (mode) {
+		case LCK_NULL: type = "NL"; break;
+		case LCK_READ: type = "CR"; break;
+		case LCK_PREAD:type = "PR"; break;
+		case LCK_WRITE:type = "PW"; break;
+		case LCK_EXCL: type = "EX"; break;
+	}
+
+	DEBUGLOG("do_lock_query: resource '%s', mode %i (%s)\n", resource, mode, type ?: "?");
+
+	return type;
+}
+
+/* This is the LOCK_LV part that happens on all nodes in the cluster -
+   it is responsible for the interaction with device-mapper and LVM */
+int do_lock_lv(unsigned char command, unsigned char lock_flags, char *resource)
+{
+	int status = 0;
+
+	DEBUGLOG("do_lock_lv: resource '%s', cmd = %s, flags = %s, critical_section = %d\n",
+		 resource, decode_locking_cmd(command), decode_flags(lock_flags), critical_section());
+
+	if (!cmd->config_valid || config_files_changed(cmd)) {
+		/* Reinitialise various settings inc. logging, filters */
+		if (do_refresh_cache()) {
+			log_error("Updated config file invalid. Aborting.");
+			return EINVAL;
+		}
+	}
+
+	pthread_mutex_lock(&lvm_lock);
+	if (lock_flags & LCK_MIRROR_NOSYNC_MODE)
+		init_mirror_in_sync(1);
+
+	if (lock_flags & LCK_DMEVENTD_MONITOR_IGNORE)
+		init_dmeventd_monitor(DMEVENTD_MONITOR_IGNORE);
+	else {
+		if (lock_flags & LCK_DMEVENTD_MONITOR_MODE)
+			init_dmeventd_monitor(1);
+		else
+			init_dmeventd_monitor(0);
+	}
+
+	cmd->partial_activation = (lock_flags & LCK_PARTIAL_MODE) ? 1 : 0;
+
+	/* clvmd should never try to read suspended device */
+	init_ignore_suspended_devices(1);
+
+	switch (command & LCK_MASK) {
+	case LCK_LV_EXCLUSIVE:
+		status = do_activate_lv(resource, command, lock_flags, LCK_EXCL);
+		break;
+
+	case LCK_LV_SUSPEND:
+		status = do_suspend_lv(resource, command, lock_flags);
+		break;
+
+	case LCK_UNLOCK:
+	case LCK_LV_RESUME:	/* if active */
+		status = do_resume_lv(resource, command, lock_flags);
+		break;
+
+	case LCK_LV_ACTIVATE:
+		status = do_activate_lv(resource, command, lock_flags, LCK_READ);
+		break;
+
+	case LCK_LV_DEACTIVATE:
+		status = do_deactivate_lv(resource, command, lock_flags);
+		break;
+
+	default:
+		DEBUGLOG("Invalid LV command 0x%x\n", command);
+		status = EINVAL;
+		break;
+	}
+
+	if (lock_flags & LCK_MIRROR_NOSYNC_MODE)
+		init_mirror_in_sync(0);
+
+	cmd->partial_activation = 0;
+
+	/* clean the pool for another command */
+	dm_pool_empty(cmd->mem);
+	pthread_mutex_unlock(&lvm_lock);
+
+	DEBUGLOG("Command return is %d, critical_section is %d\n", status, critical_section());
+	return status;
+}
+
+/* Functions to do on the local node only BEFORE the cluster-wide stuff above happens */
+int pre_lock_lv(unsigned char command, unsigned char lock_flags, char *resource)
+{
+	/* Nearly all the stuff happens cluster-wide. Apart from SUSPEND. Here we get the
+	   lock out on this node (because we are the node modifying the metadata)
+	   before suspending cluster-wide.
+	   LCKF_CONVERT is used always, local node is going to modify metadata
+	 */
+	if ((command & (LCK_SCOPE_MASK | LCK_TYPE_MASK)) == LCK_LV_SUSPEND &&
+	    (command & LCK_CLUSTER_VG)) {
+		DEBUGLOG("pre_lock_lv: resource '%s', cmd = %s, flags = %s\n",
+			 resource, decode_locking_cmd(command), decode_flags(lock_flags));
+
+		if (hold_lock(resource, LCK_WRITE, LCKF_NOQUEUE | LCKF_CONVERT))
+			return errno;
+	}
+	return 0;
+}
+
+/* Functions to do on the local node only AFTER the cluster-wide stuff above happens */
+int post_lock_lv(unsigned char command, unsigned char lock_flags,
+		 char *resource)
+{
+	int status;
+	unsigned origin_only = (lock_flags & LCK_ORIGIN_ONLY_MODE) ? 1 : 0;
+
+	/* Opposite of above, done on resume after a metadata update */
+	if ((command & (LCK_SCOPE_MASK | LCK_TYPE_MASK)) == LCK_LV_RESUME &&
+	    (command & LCK_CLUSTER_VG)) {
+		int oldmode;
+
+		DEBUGLOG
+		    ("post_lock_lv: resource '%s', cmd = %s, flags = %s\n",
+		     resource, decode_locking_cmd(command), decode_flags(lock_flags));
+
+		/* If the lock state is PW then restore it to what it was */
+		oldmode = get_current_lock(resource);
+		if (oldmode == LCK_WRITE) {
+			struct lvinfo lvi;
+
+			pthread_mutex_lock(&lvm_lock);
+			status = lv_info_by_lvid(cmd, resource, origin_only, &lvi, 0, 0);
+			pthread_mutex_unlock(&lvm_lock);
+			if (!status)
+				return EIO;
+
+			if (lvi.exists) {
+				if (hold_lock(resource, LCK_READ, LCKF_CONVERT))
+					return errno;
+			} else if (hold_unlock(resource))
+				return errno;
+		}
+	}
+	return 0;
+}
+
+/* Check if a VG is in use by LVM1 so we don't stomp on it */
+int do_check_lvm1(const char *vgname)
+{
+	int status;
+
+	status = check_lvm1_vg_inactive(cmd, vgname);
+
+	return status == 1 ? 0 : EBUSY;
+}
+
+int do_refresh_cache(void)
+{
+	DEBUGLOG("Refreshing context\n");
+	log_notice("Refreshing context");
+
+	pthread_mutex_lock(&lvm_lock);
+
+	if (!refresh_toolcontext(cmd)) {
+		pthread_mutex_unlock(&lvm_lock);
+		return -1;
+	}
+
+	init_full_scan_done(0);
+	init_ignore_suspended_devices(1);
+	lvmcache_label_scan(cmd, 2);
+	dm_pool_empty(cmd->mem);
+
+	pthread_mutex_unlock(&lvm_lock);
+
+	return 0;
+}
+
+/*
+ * Handle VG lock - drop metadata or update lvmcache state
+ */
+void do_lock_vg(unsigned char command, unsigned char lock_flags, char *resource)
+{
+	uint32_t lock_cmd = command;
+	char *vgname = resource + 2;
+
+	lock_cmd &= (LCK_SCOPE_MASK | LCK_TYPE_MASK | LCK_HOLD);
+
+	/*
+	 * Check if LCK_CACHE should be set. All P_ locks except # are cache related.
+	 */
+	if (strncmp(resource, "P_#", 3) && !strncmp(resource, "P_", 2))
+		lock_cmd |= LCK_CACHE;
+
+	DEBUGLOG("do_lock_vg: resource '%s', cmd = %s, flags = %s, critical_section = %d\n",
+		 resource, decode_full_locking_cmd(lock_cmd), decode_flags(lock_flags), critical_section());
+
+	/* P_#global causes a full cache refresh */
+	if (!strcmp(resource, "P_" VG_GLOBAL)) {
+		do_refresh_cache();
+		return;
+	}
+
+	pthread_mutex_lock(&lvm_lock);
+	switch (lock_cmd) {
+		case LCK_VG_COMMIT:
+			DEBUGLOG("vg_commit notification for VG %s\n", vgname);
+			lvmcache_commit_metadata(vgname);
+			break;
+		case LCK_VG_REVERT:
+			DEBUGLOG("vg_revert notification for VG %s\n", vgname);
+			lvmcache_drop_metadata(vgname, 1);
+			break;
+		case LCK_VG_DROP_CACHE:
+		default:
+			DEBUGLOG("Invalidating cached metadata for VG %s\n", vgname);
+			lvmcache_drop_metadata(vgname, 0);
+	}
+	pthread_mutex_unlock(&lvm_lock);
+}
+
+/*
+ * Ideally, clvmd should be started before any LVs are active
+ * but this may not be the case...
+ * I suppose this also comes in handy if clvmd crashes, not that it would!
+ */
+static int get_initial_state(struct dm_hash_table *excl_uuid)
+{
+	int lock_mode;
+	char lv[64], vg[64], flags[25], vg_flags[25];
+	char uuid[65];
+	char line[255];
+	char *lvs_cmd;
+	const char *lvm_binary = getenv("LVM_BINARY") ? : LVM_PATH;
+	FILE *lvs;
+
+	if (dm_asprintf(&lvs_cmd, "%s lvs  --config 'log{command_names=0 prefix=\"\"}' "
+			"--nolocking --noheadings -o vg_uuid,lv_uuid,lv_attr,vg_attr",
+			lvm_binary) < 0)
+		return 0;
+
+	/* FIXME: Maybe link and use liblvm2cmd directly instead of fork */
+	if (!(lvs = popen(lvs_cmd, "r"))) {
+		dm_free(lvs_cmd);
+		return 0;
+	}
+
+	while (fgets(line, sizeof(line), lvs)) {
+	        if (sscanf(line, "%s %s %s %s\n", vg, lv, flags, vg_flags) == 4) {
+
+			/* States: s:suspended a:active S:dropped snapshot I:invalid snapshot */
+		        if (strlen(vg) == 38 &&                         /* is is a valid UUID ? */
+			    (flags[4] == 'a' || flags[4] == 's') &&	/* is it active or suspended? */
+			    vg_flags[5] == 'c') {			/* is it clustered ? */
+				/* Convert hyphen-separated UUIDs into one */
+				memcpy(&uuid[0], &vg[0], 6);
+				memcpy(&uuid[6], &vg[7], 4);
+				memcpy(&uuid[10], &vg[12], 4);
+				memcpy(&uuid[14], &vg[17], 4);
+				memcpy(&uuid[18], &vg[22], 4);
+				memcpy(&uuid[22], &vg[27], 4);
+				memcpy(&uuid[26], &vg[32], 6);
+				memcpy(&uuid[32], &lv[0], 6);
+				memcpy(&uuid[38], &lv[7], 4);
+				memcpy(&uuid[42], &lv[12], 4);
+				memcpy(&uuid[46], &lv[17], 4);
+				memcpy(&uuid[50], &lv[22], 4);
+				memcpy(&uuid[54], &lv[27], 4);
+				memcpy(&uuid[58], &lv[32], 6);
+				uuid[64] = '\0';
+
+				/* Look for this lock in the list of EX locks
+				   we were passed on the command-line */
+				lock_mode = (dm_hash_lookup(excl_uuid, uuid)) ?
+					LCK_EXCL : LCK_READ;
+
+				DEBUGLOG("getting initial lock for %s\n", uuid);
+				hold_lock(uuid, lock_mode, LCKF_NOQUEUE);
+			}
+		}
+	}
+	if (fclose(lvs))
+		DEBUGLOG("lvs fclose failed: %s\n", strerror(errno));
+
+	dm_free(lvs_cmd);
+
+	return 1;
+}
+
+static void lvm2_log_fn(int level, const char *file, int line, int dm_errno,
+			const char *message)
+{
+
+	/* Send messages to the normal LVM2 logging system too,
+	   so we get debug output when it's asked for.
+ 	   We need to NULL the function ptr otherwise it will just call
+	   back into here! */
+	init_log_fn(NULL);
+	print_log(level, file, line, dm_errno, "%s", message);
+	init_log_fn(lvm2_log_fn);
+
+	/*
+	 * Ignore non-error messages, but store the latest one for returning
+	 * to the user.
+	 */
+	if (level != _LOG_ERR && level != _LOG_FATAL)
+		return;
+
+	strncpy(last_error, message, sizeof(last_error));
+	last_error[sizeof(last_error)-1] = '\0';
+}
+
+/* This checks some basic cluster-LVM configuration stuff */
+static void check_config(void)
+{
+	int locking_type;
+
+	locking_type = find_config_tree_int(cmd, "global/locking_type", 1);
+
+	if (locking_type == 3) /* compiled-in cluster support */
+		return;
+
+	if (locking_type == 2) { /* External library, check name */
+		const char *libname;
+
+		libname = find_config_tree_str(cmd, "global/locking_library",
+					  "");
+		if (strstr(libname, "liblvm2clusterlock.so"))
+			return;
+
+		log_error("Incorrect LVM locking library specified in lvm.conf, cluster operations may not work.");
+		return;
+	}
+	log_error("locking_type not set correctly in lvm.conf, cluster operations will not work.");
+}
+
+/* Backups up the LVM metadata if it's changed */
+void lvm_do_backup(const char *vgname)
+{
+	struct volume_group * vg;
+	int consistent = 0;
+
+	DEBUGLOG("Triggering backup of VG metadata for %s.\n", vgname);
+
+	pthread_mutex_lock(&lvm_lock);
+
+	vg = vg_read_internal(cmd, vgname, NULL /*vgid*/, 1, &consistent);
+
+	if (vg && consistent)
+		check_current_backup(vg);
+	else
+		log_error("Error backing up metadata, can't find VG for group %s", vgname);
+
+	release_vg(vg);
+	dm_pool_empty(cmd->mem);
+
+	pthread_mutex_unlock(&lvm_lock);
+}
+
+struct dm_hash_node *get_next_excl_lock(struct dm_hash_node *v, char **name)
+{
+	struct lv_info *lvi;
+
+	*name = NULL;
+	if (!v)
+		v = dm_hash_get_first(lv_hash);
+
+	do {
+		if (v) {
+			lvi = dm_hash_get_data(lv_hash, v);
+			DEBUGLOG("Looking for EX locks. found %x mode %d\n", lvi->lock_id, lvi->lock_mode);
+
+			if (lvi->lock_mode == LCK_EXCL) {
+				*name = dm_hash_get_key(lv_hash, v);
+			}
+			v = dm_hash_get_next(lv_hash, v);
+		}
+	} while (v && !*name);
+
+	if (*name)
+		DEBUGLOG("returning EXclusive UUID %s\n", *name);
+	return v;
+}
+
+void lvm_do_fs_unlock(void)
+{
+	pthread_mutex_lock(&lvm_lock);
+	DEBUGLOG("Syncing device names\n");
+	fs_unlock();
+	pthread_mutex_unlock(&lvm_lock);
+}
+
+/* Called to initialise the LVM context of the daemon */
+int init_clvm(struct dm_hash_table *excl_uuid)
+{
+	/* Use LOG_DAEMON for syslog messages instead of LOG_USER */
+	init_syslog(LOG_DAEMON);
+	openlog("clvmd", LOG_PID, LOG_DAEMON);
+
+	/* Initialise already held locks */
+	if (!get_initial_state(excl_uuid))
+		log_error("Cannot load initial lock states.");
+
+	if (!(cmd = create_toolcontext(1, NULL, 0, 1))) {
+		log_error("Failed to allocate command context");
+		return 0;
+	}
+
+	if (stored_errno()) {
+		destroy_toolcontext(cmd);
+		return 0;
+	}
+
+	cmd->cmd_line = "clvmd";
+
+	/* Check lvm.conf is setup for cluster-LVM */
+	check_config();
+	init_ignore_suspended_devices(1);
+
+	/* Trap log messages so we can pass them back to the user */
+	init_log_fn(lvm2_log_fn);
+	memlock_inc_daemon(cmd);
+
+	return 1;
+}
+
+void destroy_lvm(void)
+{
+	if (cmd) {
+		memlock_dec_daemon(cmd);
+		destroy_toolcontext(cmd);
+	}
+	cmd = NULL;
+}

daemons/clvmd/lvm-functions.h

@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2002-2004 Sistina Software, Inc. All rights reserved.
+ * Copyright (C) 2004-2010 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/* Functions in lvm-functions.c */
+
+#ifndef _LVM_FUNCTIONS_H
+#define _LVM_FUNCTIONS_H
+
+extern int pre_lock_lv(unsigned char lock_cmd, unsigned char lock_flags,
+		       char *resource);
+extern int do_lock_lv(unsigned char lock_cmd, unsigned char lock_flags,
+		      char *resource);
+extern const char *do_lock_query(char *resource);
+extern int post_lock_lv(unsigned char lock_cmd, unsigned char lock_flags,
+			char *resource);
+extern int do_check_lvm1(const char *vgname);
+extern int do_refresh_cache(void);
+extern int init_clvm(struct dm_hash_table *excl_uuid);
+extern void destroy_lvm(void);
+extern void init_lvhash(void);
+extern void destroy_lvhash(void);
+extern void lvm_do_backup(const char *vgname);
+extern char *get_last_lvm_error(void);
+extern void do_lock_vg(unsigned char command, unsigned char lock_flags,
+		      char *resource);
+extern struct dm_hash_node *get_next_excl_lock(struct dm_hash_node *v, char **name);
+void lvm_do_fs_unlock(void);
+
+#endif

daemons/clvmd/refresh_clvmd.c

@@ -0,0 +1,385 @@
+/*
+ * Copyright (C) 2002-2004 Sistina Software, Inc. All rights reserved.
+ * Copyright (C) 2004-2010 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/* FIXME Remove duplicated functions from this file. */
+
+/*
+ * Send a command to a running clvmd from the command-line
+ */
+
+#include "clvmd-common.h"
+
+#include "clvm.h"
+#include "refresh_clvmd.h"
+
+#include <stddef.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+typedef struct lvm_response {
+	char node[255];
+	char *response;
+	int status;
+	int len;
+} lvm_response_t;
+
+/*
+ * This gets stuck at the start of memory we allocate so we
+ * can sanity-check it at deallocation time
+ */
+#define LVM_SIGNATURE 0x434C564D
+
+static int _clvmd_sock = -1;
+
+/* Open connection to the clvm daemon */
+static int _open_local_sock(void)
+{
+	int local_socket;
+	struct sockaddr_un sockaddr;
+
+	/* Open local socket */
+	if ((local_socket = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
+		fprintf(stderr, "Local socket creation failed: %s", strerror(errno));
+		return -1;
+	}
+
+	memset(&sockaddr, 0, sizeof(sockaddr));
+	memcpy(sockaddr.sun_path, CLVMD_SOCKNAME, sizeof(CLVMD_SOCKNAME));
+
+	sockaddr.sun_family = AF_UNIX;
+
+	if (connect(local_socket,(struct sockaddr *) &sockaddr,
+		    sizeof(sockaddr))) {
+		int saved_errno = errno;
+
+		fprintf(stderr, "connect() failed on local socket: %s\n",
+			  strerror(errno));
+		if (close(local_socket))
+			return -1;
+
+		errno = saved_errno;
+		return -1;
+	}
+
+	return local_socket;
+}
+
+/* Send a request and return the status */
+static int _send_request(const char *inbuf, int inlen, char **retbuf, int no_response)
+{
+	char outbuf[PIPE_BUF];
+	struct clvm_header *outheader = (struct clvm_header *) outbuf;
+	int len;
+	unsigned off;
+	int buflen;
+	int err;
+
+	/* Send it to CLVMD */
+ rewrite:
+	if ( (err = write(_clvmd_sock, inbuf, inlen)) != inlen) {
+	        if (err == -1 && errno == EINTR)
+		        goto rewrite;
+		fprintf(stderr, "Error writing data to clvmd: %s", strerror(errno));
+		return 0;
+	}
+	if (no_response)
+		return 1;
+
+	/* Get the response */
+ reread:
+	if ((len = read(_clvmd_sock, outbuf, sizeof(struct clvm_header))) < 0) {
+	        if (errno == EINTR)
+		        goto reread;
+		fprintf(stderr, "Error reading data from clvmd: %s", strerror(errno));
+		return 0;
+	}
+
+	if (len == 0) {
+		fprintf(stderr, "EOF reading CLVMD");
+		errno = ENOTCONN;
+		return 0;
+	}
+
+	/* Allocate buffer */
+	buflen = len + outheader->arglen;
+	*retbuf = dm_malloc(buflen);
+	if (!*retbuf) {
+		errno = ENOMEM;
+		return 0;
+	}
+
+	/* Copy the header */
+	memcpy(*retbuf, outbuf, len);
+	outheader = (struct clvm_header *) *retbuf;
+
+	/* Read the returned values */
+	off = 1;		/* we've already read the first byte */
+	while (off <= outheader->arglen && len > 0) {
+		len = read(_clvmd_sock, outheader->args + off,
+			   buflen - off - offsetof(struct clvm_header, args));
+		if (len > 0)
+			off += len;
+	}
+
+	/* Was it an error ? */
+	if (outheader->status != 0) {
+		errno = outheader->status;
+
+		/* Only return an error here if there are no node-specific
+		   errors present in the message that might have more detail */
+		if (!(outheader->flags & CLVMD_FLAG_NODEERRS)) {
+			fprintf(stderr, "cluster request failed: %s\n", strerror(errno));
+			return 0;
+		}
+
+	}
+
+	return 1;
+}
+
+/* Build the structure header and parse-out wildcard node names */
+static void _build_header(struct clvm_header *head, int cmd, const char *node,
+			  unsigned int len)
+{
+	head->cmd = cmd;
+	head->status = 0;
+	head->flags = 0;
+	head->xid = 0;
+	head->clientid = 0;
+	if (len)
+		/* 1 byte is used from struct clvm_header.args[1], so -> len - 1 */
+		head->arglen = len - 1;
+	else {
+		head->arglen = 0;
+		*head->args = '\0';
+	}
+
+	/*
+	 * Translate special node names.
+	 */
+	if (!node || !strcmp(node, NODE_ALL))
+		head->node[0] = '\0';
+	else if (!strcmp(node, NODE_LOCAL)) {
+		head->node[0] = '\0';
+		head->flags = CLVMD_FLAG_LOCAL;
+	} else
+		strcpy(head->node, node);
+}
+
+/*
+ * Send a message to a(or all) node(s) in the cluster and wait for replies
+ */
+static int _cluster_request(char cmd, const char *node, void *data, int len,
+			    lvm_response_t ** response, int *num, int no_response)
+{
+	char outbuf[sizeof(struct clvm_header) + len + strlen(node) + 1];
+	char *inptr;
+	char *retbuf = NULL;
+	int status;
+	int i;
+	int num_responses = 0;
+	struct clvm_header *head = (struct clvm_header *) outbuf;
+	lvm_response_t *rarray;
+
+	*num = 0;
+
+	if (_clvmd_sock == -1)
+		_clvmd_sock = _open_local_sock();
+
+	if (_clvmd_sock == -1)
+		return 0;
+
+	_build_header(head, cmd, node, len);
+	if (len)
+		memcpy(head->node + strlen(head->node) + 1, data, len);
+
+	status = _send_request(outbuf, sizeof(struct clvm_header) +
+			       strlen(head->node) + len, &retbuf, no_response);
+	if (!status || no_response)
+		goto out;
+
+	/* Count the number of responses we got */
+	head = (struct clvm_header *) retbuf;
+	inptr = head->args;
+	while (inptr[0]) {
+		num_responses++;
+		inptr += strlen(inptr) + 1;
+		inptr += sizeof(int);
+		inptr += strlen(inptr) + 1;
+	}
+
+	/*
+	 * Allocate response array.
+	 * With an extra pair of INTs on the front to sanity
+	 * check the pointer when we are given it back to free
+	 */
+	*response = dm_malloc(sizeof(lvm_response_t) * num_responses +
+			    sizeof(int) * 2);
+	if (!*response) {
+		errno = ENOMEM;
+		status = 0;
+		goto out;
+	}
+
+	rarray = *response;
+
+	/* Unpack the response into an lvm_response_t array */
+	inptr = head->args;
+	i = 0;
+	while (inptr[0]) {
+		strcpy(rarray[i].node, inptr);
+		inptr += strlen(inptr) + 1;
+
+		memcpy(&rarray[i].status, inptr, sizeof(int));
+		inptr += sizeof(int);
+
+		rarray[i].response = dm_malloc(strlen(inptr) + 1);
+		if (rarray[i].response == NULL) {
+			/* Free up everything else and return error */
+			int j;
+			for (j = 0; j < i; j++)
+				dm_free(rarray[i].response);
+			free(*response);
+			errno = ENOMEM;
+			status = -1;
+			goto out;
+		}
+
+		strcpy(rarray[i].response, inptr);
+		rarray[i].len = strlen(inptr);
+		inptr += strlen(inptr) + 1;
+		i++;
+	}
+	*num = num_responses;
+	*response = rarray;
+
+      out:
+	if (retbuf)
+		dm_free(retbuf);
+
+	return status;
+}
+
+/* Free reply array */
+static int _cluster_free_request(lvm_response_t * response, int num)
+{
+	int i;
+
+	for (i = 0; i < num; i++) {
+		dm_free(response[i].response);
+	}
+
+	dm_free(response);
+
+	return 1;
+}
+
+int refresh_clvmd(int all_nodes)
+{
+	int num_responses;
+	char args[1]; // No args really.
+	lvm_response_t *response = NULL;
+	int saved_errno;
+	int status;
+	int i;
+
+	status = _cluster_request(CLVMD_CMD_REFRESH, all_nodes ? NODE_ALL : NODE_LOCAL, args, 0, &response, &num_responses, 0);
+
+	/* If any nodes were down then display them and return an error */
+	for (i = 0; i < num_responses; i++) {
+		if (response[i].status == EHOSTDOWN) {
+			fprintf(stderr, "clvmd not running on node %s",
+				  response[i].node);
+			status = 0;
+			errno = response[i].status;
+		} else if (response[i].status) {
+			fprintf(stderr, "Error resetting node %s: %s",
+				  response[i].node,
+				  response[i].response[0] ?
+				  	response[i].response :
+				  	strerror(response[i].status));
+			status = 0;
+			errno = response[i].status;
+		}
+	}
+
+	saved_errno = errno;
+	_cluster_free_request(response, num_responses);
+	errno = saved_errno;
+
+	return status;
+}
+
+int restart_clvmd(int all_nodes)
+{
+	int dummy, status;
+
+	status = _cluster_request(CLVMD_CMD_RESTART, all_nodes ? NODE_ALL : NODE_LOCAL, NULL, 0, NULL, &dummy, 1);
+
+	/*
+	 * FIXME: we cannot receive response, clvmd re-exec before it.
+	 *        but also should not close socket too early (the whole rq is dropped then).
+	 * FIXME: This should be handled this way:
+	 *  - client waits for RESTART ack (and socket close)
+	 *  - server restarts
+	 *  - client checks that server is ready again (VERSION command?)
+	 */
+	usleep(500000);
+
+	return status;
+}
+
+int debug_clvmd(int level, int clusterwide)
+{
+	int num_responses;
+	char args[1];
+	const char *nodes;
+	lvm_response_t *response = NULL;
+	int saved_errno;
+	int status;
+	int i;
+
+	args[0] = level;
+	if (clusterwide)
+		nodes = NODE_ALL;
+	else
+		nodes = NODE_LOCAL;
+
+	status = _cluster_request(CLVMD_CMD_SET_DEBUG, nodes, args, 1, &response, &num_responses, 0);
+
+	/* If any nodes were down then display them and return an error */
+	for (i = 0; i < num_responses; i++) {
+		if (response[i].status == EHOSTDOWN) {
+			fprintf(stderr, "clvmd not running on node %s",
+				  response[i].node);
+			status = 0;
+			errno = response[i].status;
+		} else if (response[i].status) {
+			fprintf(stderr, "Error setting debug on node %s: %s",
+				  response[i].node,
+				  response[i].response[0] ?
+				  	response[i].response :
+				  	strerror(response[i].status));
+			status = 0;
+			errno = response[i].status;
+		}
+	}
+
+	saved_errno = errno;
+	_cluster_free_request(response, num_responses);
+	errno = saved_errno;
+
+	return status;
+}

daemons/clvmd/refresh_clvmd.h

@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2007 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+
+int refresh_clvmd(int all_nodes);
+int restart_clvmd(int all_nodes);
+int debug_clvmd(int level, int clusterwide);
+

daemons/cmirrord/Makefile.in

@@ -0,0 +1,38 @@
+#
+# Copyright (C) 2009-2010 Red Hat, Inc. All rights reserved.
+#
+# This file is part of LVM2.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU General Public License v.2.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+CPG_LIBS = @CPG_LIBS@
+CPG_CFLAGS = @CPG_CFLAGS@
+SACKPT_LIBS = @SACKPT_LIBS@
+SACKPT_CFLAGS = @SACKPT_CFLAGS@
+
+SOURCES = clogd.c cluster.c compat.c functions.c link_mon.c local.c logging.c
+
+TARGETS = cmirrord
+
+include $(top_builddir)/make.tmpl
+
+LIBS += -ldevmapper
+LMLIBS += $(CPG_LIBS) $(SACKPT_LIBS)
+CFLAGS += $(CPG_CFLAGS) $(SACKPT_CFLAGS)
+
+cmirrord: $(OBJECTS) $(top_builddir)/lib/liblvm-internal.a
+	$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $(OBJECTS) \
+		$(LVMLIBS) $(LMLIBS) $(LIBS)
+
+install: $(TARGETS)
+	$(INSTALL_PROGRAM) -D cmirrord $(usrsbindir)/cmirrord

daemons/cmirrord/clogd.c

@@ -0,0 +1,246 @@
+/*
+ * Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#include "logging.h"
+#include "common.h"
+#include "functions.h"
+#include "link_mon.h"
+#include "local.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+static volatile sig_atomic_t exit_now = 0;
+/* FIXME Review signal handling.  Should be volatile sig_atomic_t */
+static sigset_t signal_mask;
+static volatile sig_atomic_t signal_received;
+
+static void process_signals(void);
+static void daemonize(void);
+static void init_all(void);
+static void cleanup_all(void);
+
+int main(int argc __attribute__((unused)), char *argv[] __attribute__((unused)))
+{
+	daemonize();
+
+	init_all();
+
+	/* Parent can now exit, we're ready to handle requests */
+	kill(getppid(), SIGTERM);
+
+	LOG_PRINT("Starting cmirrord:");
+	LOG_PRINT(" Built: "__DATE__" "__TIME__"\n");
+	LOG_DBG(" Compiled with debugging.");
+
+	while (!exit_now) {
+		links_monitor();
+
+		links_issue_callbacks();
+
+		process_signals();
+	}
+	exit(EXIT_SUCCESS);
+}
+
+/*
+ * parent_exit_handler: exit the parent
+ * @sig: the signal
+ *
+ */
+static void parent_exit_handler(int sig __attribute__((unused)))
+{
+	exit_now = 1;
+}
+
+static void sig_handler(int sig)
+{
+	/* FIXME Races - don't touch signal_mask here. */
+	sigaddset(&signal_mask, sig);
+	signal_received = 1;
+}
+
+static void process_signal(int sig){
+	int r = 0;
+
+	switch(sig) {
+	case SIGINT:
+	case SIGQUIT:
+	case SIGTERM:
+	case SIGHUP:
+		r += log_status();
+		break;
+	case SIGUSR1:
+	case SIGUSR2:
+		log_debug();
+		/*local_debug();*/
+		cluster_debug();
+		return;
+	default:
+		LOG_PRINT("Unknown signal received... ignoring");
+		return;
+	}
+
+	if (!r) {
+		LOG_DBG("No current cluster logs... safe to exit.");
+		cleanup_all();
+		exit(EXIT_SUCCESS);
+	}
+
+	LOG_ERROR("Cluster logs exist.  Refusing to exit.");
+}
+
+static void process_signals(void)
+{
+	int x;
+
+	if (!signal_received)
+		return;
+
+	signal_received = 0;
+
+	for (x = 1; x < _NSIG; x++) {
+		if (sigismember(&signal_mask, x)) {
+			sigdelset(&signal_mask, x);
+			process_signal(x);
+		}
+	}
+}
+
+static void remove_lockfile(void)
+{
+	if (unlink(CMIRRORD_PIDFILE))
+		LOG_ERROR("Unable to remove \"" CMIRRORD_PIDFILE "\" %s", strerror(errno));
+}
+
+/*
+ * daemonize
+ *
+ * Performs the steps necessary to become a daemon.
+ */
+static void daemonize(void)
+{
+	int pid;
+	int status;
+	int devnull;
+
+	if ((devnull = open("/dev/null", O_RDWR)) == -1) {
+		LOG_ERROR("Can't open /dev/null: %s", strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	signal(SIGTERM, &parent_exit_handler);
+
+	pid = fork();
+
+	if (pid < 0) {
+		LOG_ERROR("Unable to fork()");
+		exit(EXIT_FAILURE);
+	}
+
+	if (pid) {
+		/* Parent waits here for child to get going */
+		while (!waitpid(pid, &status, WNOHANG) && !exit_now);
+		if (exit_now)
+			exit(EXIT_SUCCESS);
+
+		switch (WEXITSTATUS(status)) {
+		case EXIT_LOCKFILE:
+			LOG_ERROR("Failed to create lockfile");
+			LOG_ERROR("Process already running?");
+			break;
+		case EXIT_KERNEL_SOCKET:
+			LOG_ERROR("Unable to create netlink socket");
+			break;
+		case EXIT_KERNEL_BIND:
+			LOG_ERROR("Unable to bind to netlink socket");
+			break;
+		case EXIT_KERNEL_SETSOCKOPT:
+			LOG_ERROR("Unable to setsockopt on netlink socket");
+			break;
+		case EXIT_CLUSTER_CKPT_INIT:
+			LOG_ERROR("Unable to initialize checkpoint service");
+			LOG_ERROR("Has the cluster infrastructure been started?");
+			break;
+		case EXIT_FAILURE:
+			LOG_ERROR("Failed to start: Generic error");
+			break;
+		default:
+			LOG_ERROR("Failed to start: Unknown error");
+			break;
+		}
+		exit(EXIT_FAILURE);
+	}
+
+	setsid();
+	chdir("/");
+	umask(0);
+
+	if (close(0) || close(1) || close(2)) {
+		LOG_ERROR("Failed to close terminal FDs");
+		exit(EXIT_FAILURE);
+	}
+
+	if ((dup2(devnull, 0) < 0) || /* reopen stdin */
+	    (dup2(devnull, 1) < 0) || /* reopen stdout */
+	    (dup2(devnull, 2) < 0))   /* reopen stderr */
+		exit(EXIT_FAILURE);
+
+	LOG_OPEN("cmirrord", LOG_PID, LOG_DAEMON);
+
+	(void) dm_prepare_selinux_context(CMIRRORD_PIDFILE, S_IFREG);
+	if (dm_create_lockfile(CMIRRORD_PIDFILE) == 0)
+		exit(EXIT_LOCKFILE);
+	(void) dm_prepare_selinux_context(NULL, 0);
+
+	atexit(remove_lockfile);
+
+	/* FIXME Replace with sigaction. (deprecated) */
+	signal(SIGINT, &sig_handler);
+	signal(SIGQUIT, &sig_handler);
+	signal(SIGTERM, &sig_handler);
+	signal(SIGHUP, &sig_handler);
+	signal(SIGPIPE, SIG_IGN);
+	signal(SIGUSR1, &sig_handler);
+	signal(SIGUSR2, &sig_handler);
+	sigemptyset(&signal_mask);
+	signal_received = 0;
+}
+
+/*
+ * init_all
+ *
+ * Initialize modules.  Exit on failure.
+ */
+static void init_all(void)
+{
+	int r;
+
+	if ((r = init_local()) ||
+	    (r = init_cluster())) {
+		exit(r);
+	}
+}
+
+/*
+ * cleanup_all
+ *
+ * Clean up before exiting
+ */
+static void cleanup_all(void)
+{
+	cleanup_local();
+	cleanup_cluster();
+}

daemons/cmirrord/cluster.h

@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#ifndef _LVM_CLOG_CLUSTER_H
+#define _LVM_CLOG_CLUSTER_H
+
+#include "dm-log-userspace.h"
+#include "libdevmapper.h"
+
+#define DM_ULOG_RESPONSE 0x1000U /* in last byte of 32-bit value */
+#define DM_ULOG_CHECKPOINT_READY 21
+#define DM_ULOG_MEMBER_JOIN      22
+
+/*
+ * There is other information in addition to what can
+ * be found in the dm_ulog_request structure that we
+ * need for processing.  'clog_request' is the wrapping
+ * structure we use to make the additional fields
+ * available.
+ */
+struct clog_request {
+	/*
+	 * If we don't use a union, the structure size will
+	 * vary between 32-bit and 64-bit machines.  So, we
+	 * pack two 64-bit version numbers in there to force
+	 * the size of the structure to be the same.
+	 *
+	 * The two version numbers also help us with endian
+	 * issues.  The first is always little endian, while
+	 * the second is in native format of the sending
+	 * machine.  If the two are equal, there is no need
+	 * to do endian conversions.
+	 */
+	union {
+		uint64_t version[2]; /* LE version and native version */
+		struct dm_list list;
+	} u;
+
+	/*
+	 * 'originator' is the machine from which the requests
+	 * was made.
+	 */
+	uint32_t originator;
+
+	/*
+	 * 'pit_server' is the "point-in-time" server for the
+	 * request.  (I.e.  The machine that was the server at
+	 * the time the request was issued - only important during
+	 * startup.
+	 */
+	uint32_t pit_server;
+
+	/*
+	 * The request from the kernel that is being processed
+	 */
+	struct dm_ulog_request u_rq;
+};
+
+int init_cluster(void);
+void cleanup_cluster(void);
+void cluster_debug(void);
+
+int create_cluster_cpg(char *uuid, uint64_t luid);
+int destroy_cluster_cpg(char *uuid);
+
+int cluster_send(struct clog_request *rq);
+
+#endif /* _LVM_CLOG_CLUSTER_H */

daemons/cmirrord/common.h

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#ifndef _LVM_CLOG_COMMON_H
+#define _LVM_CLOG_COMMON_H
+
+/*
+ * If there are problems when forking off to become a daemon,
+ * the child will exist with one of these codes.  This allows
+ * the parent to know the reason for the failure and print it
+ * to the launching terminal.
+ *
+ * #define EXIT_SUCCESS 0 (from stdlib.h)
+ * #define EXIT_FAILURE 1 (from stdlib.h)
+ */
+#define EXIT_LOCKFILE              2
+#define EXIT_KERNEL_SOCKET         3 /* Failed netlink socket create */
+#define EXIT_KERNEL_BIND           4
+#define EXIT_KERNEL_SETSOCKOPT     5
+#define EXIT_CLUSTER_CKPT_INIT     6 /* Failed to init checkpoint */
+#define EXIT_QUEUE_NOMEM           7
+
+#define DM_ULOG_REQUEST_SIZE 1024
+
+#endif /* _LVM_CLOG_COMMON_H */

daemons/cmirrord/compat.c

@@ -0,0 +1,210 @@
+/*
+ * Copyright (C) 2010 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ */
+#include "logging.h"
+#include "cluster.h"
+#include "compat.h"
+#include "xlate.h"
+
+#include <errno.h>
+
+/*
+ * Older versions of the log daemon communicate with different
+ * versions of the inter-machine communication structure, which
+ * varies in size and fields.  The older versions append the
+ * standard upstream version of the structure to every request.
+ * COMPAT_OFFSET is where the upstream structure starts.
+ */
+#define COMPAT_OFFSET 256
+
+static void v5_data_endian_switch(struct clog_request *rq, int to_network __attribute__((unused)))
+{
+	int i, end;
+	int64_t *pi64;
+	uint64_t *pu64;
+	uint32_t rq_type = rq->u_rq.request_type & ~DM_ULOG_RESPONSE;
+
+	if (rq->u_rq.request_type & DM_ULOG_RESPONSE) {
+		switch (rq_type) {
+		case DM_ULOG_CTR:
+		case DM_ULOG_DTR:
+			LOG_ERROR("Invalid response type in endian switch");
+			exit(EXIT_FAILURE);
+
+		case DM_ULOG_PRESUSPEND:
+		case DM_ULOG_POSTSUSPEND:
+		case DM_ULOG_RESUME:
+		case DM_ULOG_FLUSH:
+		case DM_ULOG_MARK_REGION:
+		case DM_ULOG_CLEAR_REGION:
+		case DM_ULOG_SET_REGION_SYNC:
+		case DM_ULOG_CHECKPOINT_READY:
+		case DM_ULOG_MEMBER_JOIN:
+		case DM_ULOG_STATUS_INFO:
+		case DM_ULOG_STATUS_TABLE:
+			/* No outbound data */
+			break;
+
+		case DM_ULOG_GET_REGION_SIZE:
+		case DM_ULOG_GET_SYNC_COUNT:
+			pu64 = (uint64_t *)rq->u_rq.data;
+			*pu64 = xlate64(*pu64);
+			break;
+		case DM_ULOG_IS_CLEAN:
+		case DM_ULOG_IN_SYNC:
+			pi64 = (int64_t *)rq->u_rq.data;
+			*pi64 = xlate64(*pi64);
+			break;
+		case DM_ULOG_GET_RESYNC_WORK:
+		case DM_ULOG_IS_REMOTE_RECOVERING:
+			pi64 = (int64_t *)rq->u_rq.data;
+			pu64 = ((uint64_t *)rq->u_rq.data) + 1;
+			*pi64 = xlate64(*pi64);
+			*pu64 = xlate64(*pu64);
+			break;
+		default:
+			LOG_ERROR("Unknown request type, %u", rq_type);
+			return;
+		}
+	} else {
+		switch (rq_type) {
+		case DM_ULOG_CTR:
+		case DM_ULOG_DTR:
+			LOG_ERROR("Invalid request type in endian switch");
+			exit(EXIT_FAILURE);
+
+		case DM_ULOG_PRESUSPEND:
+		case DM_ULOG_POSTSUSPEND:
+		case DM_ULOG_RESUME:
+		case DM_ULOG_GET_REGION_SIZE:
+		case DM_ULOG_FLUSH:
+		case DM_ULOG_GET_RESYNC_WORK:
+		case DM_ULOG_GET_SYNC_COUNT:
+		case DM_ULOG_STATUS_INFO:
+		case DM_ULOG_STATUS_TABLE:
+		case DM_ULOG_CHECKPOINT_READY:
+		case DM_ULOG_MEMBER_JOIN:
+			/* No incoming data */
+			break;
+		case DM_ULOG_IS_CLEAN:
+		case DM_ULOG_IN_SYNC:
+		case DM_ULOG_IS_REMOTE_RECOVERING:
+			pu64 = (uint64_t *)rq->u_rq.data;
+			*pu64 = xlate64(*pu64);
+			break;
+		case DM_ULOG_MARK_REGION:
+		case DM_ULOG_CLEAR_REGION:
+			end = rq->u_rq.data_size/sizeof(uint64_t);
+
+			pu64 = (uint64_t *)rq->u_rq.data;
+			for (i = 0; i < end; i++)
+				pu64[i] = xlate64(pu64[i]);
+			break;
+		case DM_ULOG_SET_REGION_SYNC:
+			pu64 = (uint64_t *)rq->u_rq.data;
+			pi64 = ((int64_t *)rq->u_rq.data) + 1;
+			*pu64 = xlate64(*pu64);
+			*pi64 = xlate64(*pi64);
+			break;
+		default:
+			LOG_ERROR("Unknown request type, %u", rq_type);
+			exit(EXIT_FAILURE);
+		}
+	}
+}
+
+static int v5_endian_to_network(struct clog_request *rq)
+{
+	int size;
+	struct dm_ulog_request *u_rq = &rq->u_rq;
+
+	size = sizeof(*rq) + u_rq->data_size;
+
+	u_rq->error = xlate32(u_rq->error);
+	u_rq->seq = xlate32(u_rq->seq);
+	u_rq->request_type = xlate32(u_rq->request_type);
+	u_rq->data_size = xlate64(u_rq->data_size);
+
+	rq->originator = xlate32(rq->originator);
+
+	v5_data_endian_switch(rq, 1);
+
+	return size;
+}
+
+int clog_request_to_network(struct clog_request *rq)
+{
+	int r;
+
+	/* FIXME: Remove this safety check */
+	if (rq->u.version[0] != xlate64(rq->u.version[1])) {
+		LOG_ERROR("Programmer error:  version[0] must be LE");
+		exit(EXIT_FAILURE);
+	}
+
+	/*
+	 * Are we already running in the endian mode we send
+	 * over the wire?
+	 */
+	if (rq->u.version[0] == rq->u.version[1])
+		return 0;
+
+	r = v5_endian_to_network(rq);
+	if (r < 0)
+		return r;
+	return 0;
+}
+
+static int v5_endian_from_network(struct clog_request *rq)
+{
+	int size;
+	struct dm_ulog_request *u_rq = &rq->u_rq;
+
+	u_rq->error = xlate32(u_rq->error);
+	u_rq->seq = xlate32(u_rq->seq);
+	u_rq->request_type = xlate32(u_rq->request_type);
+	u_rq->data_size = xlate64(u_rq->data_size);
+
+	rq->originator = xlate32(rq->originator);
+
+	size = sizeof(*rq) + u_rq->data_size;
+
+	v5_data_endian_switch(rq, 0);
+
+	return size;
+}
+
+int clog_request_from_network(void *data, size_t data_len)
+{
+	uint64_t *vp = data;
+	uint64_t version = xlate64(vp[0]);
+	uint64_t unconverted_version = vp[1];
+	struct clog_request *rq = data;
+
+	switch (version) {
+	case 5: /* Upstream */
+		if (version == unconverted_version)
+			return 0;
+		break;
+	case 4: /* RHEL 5.[45] */
+	case 3: /* RHEL 5.3 */
+	case 2: /* RHEL 5.2 */
+		/* FIXME: still need to account for payload */
+		if (data_len < (COMPAT_OFFSET + sizeof(*rq)))
+			return -ENOSPC;
+
+		rq = (struct clog_request *)((char *)data + COMPAT_OFFSET);
+		break;
+	default:
+		LOG_ERROR("Unable to process cluster message: "
+			  "Incompatible version");
+		return -EINVAL;
+	}
+
+	v5_endian_from_network(rq);
+	return 0;
+}

daemons/cmirrord/compat.h

@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2010 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ */
+#ifndef _LVM_CLOG_COMPAT_H
+#define _LVM_CLOG_COMPAT_H
+
+/*
+ * The intermachine communication structure version are:
+ *	0: Unused
+ *	1: Never in the wild
+ *	2: RHEL 5.2
+ *	3: RHEL 5.3
+ *	4: RHEL 5.4, RHEL 5.5
+ *	5: RHEL 6, Current Upstream Format
+ */
+#define CLOG_TFR_VERSION 5
+
+int clog_request_to_network(struct clog_request *rq);
+int clog_request_from_network(void *data, size_t data_len);
+
+#endif /* _LVM_CLOG_COMPAT_H */

daemons/cmirrord/functions.h

@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#ifndef _LVM_CLOG_FUNCTIONS_H
+#define _LVM_CLOG_FUNCTIONS_H
+
+#include "dm-log-userspace.h"
+#include "cluster.h"
+
+#define LOG_RESUMED   1
+#define LOG_SUSPENDED 2
+
+int local_resume(struct dm_ulog_request *rq);
+int cluster_postsuspend(char *, uint64_t);
+
+int do_request(struct clog_request *rq, int server);
+int push_state(const char *uuid, uint64_t luid,
+	       const char *which, char **buf, uint32_t debug_who);
+int pull_state(const char *uuid, uint64_t luid,
+	       const char *which, char *buf, int size);
+
+int log_get_state(struct dm_ulog_request *rq);
+int log_status(void);
+void log_debug(void);
+
+#endif /* _LVM_CLOG_FUNCTIONS_H */

daemons/cmirrord/link_mon.c

@@ -0,0 +1,151 @@
+/*
+ * Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#include "logging.h"
+#include "link_mon.h"
+
+#include <errno.h>
+#include <poll.h>
+#include <stdlib.h>
+
+struct link_callback {
+	int fd;
+	const char *name;
+	void *data;
+	int (*callback)(void *data);
+
+	struct link_callback *next;
+};
+
+static unsigned used_pfds = 0;
+static unsigned free_pfds = 0;
+static struct pollfd *pfds = NULL;
+static struct link_callback *callbacks = NULL;
+
+int links_register(int fd, const char *name, int (*callback)(void *data), void *data)
+{
+	unsigned i;
+	struct link_callback *lc;
+
+	for (i = 0; i < used_pfds; i++) {
+		if (fd == pfds[i].fd) {
+			LOG_ERROR("links_register: Duplicate file descriptor");
+			return -EINVAL;
+		}
+	}
+
+	lc = malloc(sizeof(*lc));
+	if (!lc)
+		return -ENOMEM;
+
+	lc->fd = fd;
+	lc->name = name;
+	lc->data = data;
+	lc->callback = callback;
+
+	if (!free_pfds) {
+		struct pollfd *tmp;
+		tmp = realloc(pfds, sizeof(struct pollfd) * ((used_pfds*2) + 1));
+		if (!tmp) {
+			free(lc);
+			return -ENOMEM;
+		}
+		
+		pfds = tmp;
+		free_pfds = used_pfds + 1;
+	}
+
+	free_pfds--;
+	pfds[used_pfds].fd = fd;
+	pfds[used_pfds].events = POLLIN;
+	pfds[used_pfds].revents = 0;
+	used_pfds++;
+
+	lc->next = callbacks;
+	callbacks = lc;
+	LOG_DBG("Adding %s/%d", lc->name, lc->fd);
+	LOG_DBG(" used_pfds = %u, free_pfds = %u",
+		used_pfds, free_pfds);
+
+	return 0;
+}
+
+int links_unregister(int fd)
+{
+	unsigned i;
+	struct link_callback *p, *c;
+
+	for (i = 0; i < used_pfds; i++)
+		if (fd == pfds[i].fd) {
+			/* entire struct is copied (overwritten) */
+			pfds[i] = pfds[used_pfds - 1];
+			used_pfds--;
+			free_pfds++;
+		}
+
+	for (p = NULL, c = callbacks; c; p = c, c = c->next)
+		if (fd == c->fd) {
+			LOG_DBG("Freeing up %s/%d", c->name, c->fd);
+			LOG_DBG(" used_pfds = %u, free_pfds = %u",
+				used_pfds, free_pfds);
+			if (p)
+				p->next = c->next;
+			else
+				callbacks = c->next;
+			free(c);
+			break;
+		}
+
+	return 0;
+}
+
+int links_monitor(void)
+{
+	unsigned i;
+	int r;
+
+	for (i = 0; i < used_pfds; i++) {
+		pfds[i].revents = 0;
+	}
+
+	r = poll(pfds, used_pfds, -1);
+	if (r <= 0)
+		return r;
+
+	r = 0;
+	/* FIXME: handle POLLHUP */
+	for (i = 0; i < used_pfds; i++)
+		if (pfds[i].revents & POLLIN) {
+			LOG_DBG("Data ready on %d", pfds[i].fd);
+				
+			/* FIXME: Add this back return 1;*/
+			r++;
+		}
+
+	return r;
+}
+
+int links_issue_callbacks(void)
+{
+	unsigned i;
+	struct link_callback *lc;
+
+	for (i = 0; i < used_pfds; i++)
+		if (pfds[i].revents & POLLIN)
+			for (lc = callbacks; lc; lc = lc->next)
+				if (pfds[i].fd == lc->fd) {
+					LOG_DBG("Issuing callback on %s/%d",
+						lc->name, lc->fd);
+					lc->callback(lc->data);
+					break;
+				}
+	return 0;
+}

daemons/cmirrord/link_mon.h

@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#ifndef _LVM_CLOG_LINK_MON_H
+#define _LVM_CLOG_LINK_MON_H
+
+int links_register(int fd, const char *name, int (*callback)(void *data), void *data);
+int links_unregister(int fd);
+int links_monitor(void);
+int links_issue_callbacks(void);
+
+#endif /* _LVM_CLOG_LINK_MON_H */

daemons/cmirrord/local.c

@@ -0,0 +1,416 @@
+/*
+ * Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#include "logging.h"
+#include "common.h"
+#include "functions.h"
+#include "link_mon.h"
+#include "local.h"
+
+#include <errno.h>
+#include <sys/socket.h>
+#include <linux/connector.h>
+#include <linux/netlink.h>
+#include <unistd.h>
+
+#ifndef CN_IDX_DM
+/* Kernel 2.6.31 is required to run this code */
+#define CN_IDX_DM                       0x7     /* Device Mapper */
+#define CN_VAL_DM_USERSPACE_LOG         0x1
+#endif
+
+static int cn_fd;  /* Connector (netlink) socket fd */
+static char recv_buf[2048];
+static char send_buf[2048];
+
+
+/* FIXME: merge this function with kernel_send_helper */
+static int kernel_ack(uint32_t seq, int error)
+{
+	int r;
+	struct nlmsghdr *nlh = (struct nlmsghdr *)send_buf;
+	struct cn_msg *msg = NLMSG_DATA(nlh);
+
+	if (error < 0) {
+		LOG_ERROR("Programmer error: error codes must be positive");
+		return -EINVAL;
+	}
+
+	memset(send_buf, 0, sizeof(send_buf));
+
+	nlh->nlmsg_seq = 0;
+	nlh->nlmsg_pid = getpid();
+	nlh->nlmsg_type = NLMSG_DONE;
+	nlh->nlmsg_len = NLMSG_LENGTH(sizeof(struct cn_msg));
+	nlh->nlmsg_flags = 0;
+
+	msg->len = 0;
+	msg->id.idx = CN_IDX_DM;
+	msg->id.val = CN_VAL_DM_USERSPACE_LOG;
+	msg->seq = seq;
+	msg->ack = error;
+
+	r = send(cn_fd, nlh, NLMSG_LENGTH(sizeof(struct cn_msg)), 0);
+	/* FIXME: do better error processing */
+	if (r <= 0)
+		return -EBADE;
+
+	return 0;
+}
+
+
+/*
+ * kernel_recv
+ * @rq: the newly allocated request from kernel
+ *
+ * Read requests from the kernel and allocate space for the new request.
+ * If there is no request from the kernel, *rq is NULL.
+ *
+ * This function is not thread safe due to returned stack pointer.  In fact,
+ * the returned pointer must not be in-use when this function is called again.
+ *
+ * Returns: 0 on success, -EXXX on error
+ */
+static int kernel_recv(struct clog_request **rq)
+{
+	int r = 0;
+	ssize_t len;
+	char *foo;
+	struct cn_msg *msg;
+	struct dm_ulog_request *u_rq;
+	struct nlmsghdr *nlmsg_h;
+
+	*rq = NULL;
+	memset(recv_buf, 0, sizeof(recv_buf));
+
+	len = recv(cn_fd, recv_buf, sizeof(recv_buf), 0);
+	if (len < 0) {
+		LOG_ERROR("Failed to recv message from kernel");
+		r = -errno;
+		goto fail;
+	}
+
+	nlmsg_h = (struct nlmsghdr *)recv_buf;
+	switch (nlmsg_h->nlmsg_type) {
+	case NLMSG_ERROR:
+		LOG_ERROR("Unable to recv message from kernel: NLMSG_ERROR");
+		r = -EBADE;
+		goto fail;
+	case NLMSG_DONE:
+		msg = (struct cn_msg *)NLMSG_DATA((struct nlmsghdr *)recv_buf);
+		len -= (ssize_t)sizeof(struct nlmsghdr);
+
+		if (len < (ssize_t)sizeof(struct cn_msg)) {
+			LOG_ERROR("Incomplete request from kernel received");
+			r = -EBADE;
+			goto fail;
+		}
+
+		if (msg->len > DM_ULOG_REQUEST_SIZE) {
+			LOG_ERROR("Not enough space to receive kernel request (%d/%d)",
+				  msg->len, DM_ULOG_REQUEST_SIZE);
+			r = -EBADE;
+			goto fail;
+		}
+
+		if (!msg->len)
+			LOG_ERROR("Zero length message received");
+
+		len -= (ssize_t)sizeof(struct cn_msg);
+
+		if (len < msg->len)
+			LOG_ERROR("len = %zd, msg->len = %" PRIu16, len, msg->len);
+
+		msg->data[msg->len] = '\0'; /* Cleaner way to ensure this? */
+		u_rq = (struct dm_ulog_request *)msg->data;
+
+		if (!u_rq->request_type) {
+			LOG_DBG("Bad transmission, requesting resend [%u]",
+				msg->seq);
+			r = -EAGAIN;
+
+			if (kernel_ack(msg->seq, EAGAIN)) {
+				LOG_ERROR("Failed to NACK kernel transmission [%u]",
+					  msg->seq);
+				r = -EBADE;
+			}
+		}
+
+		/*
+		 * Now we've got sizeof(struct cn_msg) + sizeof(struct nlmsghdr)
+		 * worth of space that precede the request structure from the
+		 * kernel.  Since that space isn't going to be used again, we
+		 * can take it for our purposes; rather than allocating a whole
+		 * new structure and doing a memcpy.
+		 *
+		 * We should really make sure 'clog_request' doesn't grow
+		 * beyond what is available to us, but we need only check it
+		 * once... perhaps at compile time?
+		 */
+		foo = (char *)u_rq;
+		foo -= (sizeof(struct clog_request) - sizeof(struct dm_ulog_request));
+		*rq = (struct clog_request *) foo;
+
+		/* Clear the wrapper container fields */
+		memset(*rq, 0, (size_t)((char *)u_rq - (char *)(*rq)));
+		break;
+	default:
+		LOG_ERROR("Unknown nlmsg_type");
+		r = -EBADE;
+	}
+
+fail:
+	if (r)
+		*rq = NULL;
+
+	return (r == -EAGAIN) ? 0 : r;
+}
+
+static int kernel_send_helper(void *data, uint16_t out_size)
+{
+	int r;
+	struct nlmsghdr *nlh;
+	struct cn_msg *msg;
+
+	memset(send_buf, 0, sizeof(send_buf));
+
+	nlh = (struct nlmsghdr *)send_buf;
+	nlh->nlmsg_seq = 0;  /* FIXME: Is this used? */
+	nlh->nlmsg_pid = getpid();
+	nlh->nlmsg_type = NLMSG_DONE;
+	nlh->nlmsg_len = NLMSG_LENGTH(out_size + sizeof(struct cn_msg));
+	nlh->nlmsg_flags = 0;
+
+	msg = NLMSG_DATA(nlh);
+	memcpy(msg->data, data, out_size);
+	msg->len = out_size;
+	msg->id.idx = CN_IDX_DM;
+	msg->id.val = CN_VAL_DM_USERSPACE_LOG;
+	msg->seq = 0;
+
+	r = send(cn_fd, nlh, NLMSG_LENGTH(out_size + sizeof(struct cn_msg)), 0);
+	/* FIXME: do better error processing */
+	if (r <= 0)
+		return -EBADE;
+
+	return 0;
+}
+
+/*
+ * do_local_work
+ *
+ * Any processing errors are placed in the 'rq'
+ * structure to be reported back to the kernel.
+ * It may be pointless for this function to
+ * return an int.
+ *
+ * Returns: 0 on success, -EXXX on failure
+ */
+static int do_local_work(void *data __attribute__((unused)))
+{
+	int r;
+	struct clog_request *rq;
+	struct dm_ulog_request *u_rq = NULL;
+
+	r = kernel_recv(&rq);
+	if (r)
+		return r;
+
+	if (!rq)
+		return 0;
+
+	u_rq = &rq->u_rq;
+	LOG_DBG("[%s]  Request from kernel received: [%s/%u]",
+		SHORT_UUID(u_rq->uuid), RQ_TYPE(u_rq->request_type),
+		u_rq->seq);
+	switch (u_rq->request_type) {
+	case DM_ULOG_CTR:
+	case DM_ULOG_DTR:
+	case DM_ULOG_GET_REGION_SIZE:
+	case DM_ULOG_IN_SYNC:
+	case DM_ULOG_GET_SYNC_COUNT:
+	case DM_ULOG_STATUS_INFO:
+	case DM_ULOG_STATUS_TABLE:
+	case DM_ULOG_PRESUSPEND:
+		/* We do not specify ourselves as server here */
+		r = do_request(rq, 0);
+		if (r)
+			LOG_DBG("Returning failed request to kernel [%s]",
+				RQ_TYPE(u_rq->request_type));
+		r = kernel_send(u_rq);
+		if (r)
+			LOG_ERROR("Failed to respond to kernel [%s]",
+				  RQ_TYPE(u_rq->request_type));
+			
+		break;
+	case DM_ULOG_RESUME:
+		/*
+		 * Resume is a special case that requires a local
+		 * component to join the CPG, and a cluster component
+		 * to handle the request.
+		 */
+		r = local_resume(u_rq);
+		if (r) {
+			LOG_DBG("Returning failed request to kernel [%s]",
+				RQ_TYPE(u_rq->request_type));
+			r = kernel_send(u_rq);
+			if (r)
+				LOG_ERROR("Failed to respond to kernel [%s]",
+					  RQ_TYPE(u_rq->request_type));
+			break;
+		}
+		/* ELSE, fall through */
+	case DM_ULOG_IS_CLEAN:
+	case DM_ULOG_FLUSH:
+	case DM_ULOG_MARK_REGION:
+	case DM_ULOG_GET_RESYNC_WORK:
+	case DM_ULOG_SET_REGION_SYNC:
+	case DM_ULOG_IS_REMOTE_RECOVERING:
+	case DM_ULOG_POSTSUSPEND:
+		r = cluster_send(rq);
+		if (r) {
+			u_rq->data_size = 0;
+			u_rq->error = r;
+			kernel_send(u_rq);
+		}
+
+		break;
+	case DM_ULOG_CLEAR_REGION:
+		r = kernel_ack(u_rq->seq, 0);
+
+		r = cluster_send(rq);
+		if (r) {
+			/*
+			 * FIXME: store error for delivery on flush
+			 *        This would allow us to optimize MARK_REGION
+			 *        too.
+			 */
+		}
+
+		break;
+	default:
+		LOG_ERROR("Invalid log request received (%u), ignoring.",
+			  u_rq->request_type);
+
+		return 0;
+	}
+
+	if (r && !u_rq->error)
+		u_rq->error = r;
+
+	return r;
+}
+
+/*
+ * kernel_send
+ * @u_rq: result to pass back to kernel
+ *
+ * This function returns the u_rq structure
+ * (containing the results) to the kernel.
+ * It then frees the structure.
+ *
+ * WARNING: should the structure be freed if
+ * there is an error?  I vote 'yes'.  If the
+ * kernel doesn't get the response, it should
+ * resend the request.
+ *
+ * Returns: 0 on success, -EXXX on failure
+ */
+int kernel_send(struct dm_ulog_request *u_rq)
+{
+	int r;
+	uint16_t size;
+
+	if (!u_rq)
+		return -EINVAL;
+
+	size = (uint16_t)(sizeof(struct dm_ulog_request) + u_rq->data_size);
+
+	if (!u_rq->data_size && !u_rq->error) {
+		/* An ACK is all that is needed */
+
+		/* FIXME: add ACK code */
+	} else if (size > DM_ULOG_REQUEST_SIZE) {
+		/*
+		 * If we gotten here, we've already overrun
+		 * our allotted space somewhere.
+		 *
+		 * We must do something, because the kernel
+		 * is waiting for a response.
+		 */
+		LOG_ERROR("Not enough space to respond to server");
+		u_rq->error = -ENOSPC;
+		size = sizeof(struct dm_ulog_request);
+	}
+
+	r = kernel_send_helper(u_rq, size);
+	if (r)
+		LOG_ERROR("Failed to send msg to kernel.");
+
+	return r;
+}
+
+/*
+ * init_local
+ *
+ * Initialize kernel communication socket (netlink)
+ *
+ * Returns: 0 on success, values from common.h on failure
+ */
+int init_local(void)
+{
+	int r = 0;
+	unsigned opt;
+	struct sockaddr_nl addr;
+
+	cn_fd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_CONNECTOR);
+	if (cn_fd < 0)
+		return EXIT_KERNEL_SOCKET;
+
+	/* memset to fix valgrind complaint */
+	memset(&addr, 0, sizeof(struct sockaddr_nl));
+
+	addr.nl_family = AF_NETLINK;
+	addr.nl_groups = CN_IDX_DM;
+	addr.nl_pid = 0;
+
+	r = bind(cn_fd, (struct sockaddr *) &addr, sizeof(addr));
+	if (r < 0) {
+		close(cn_fd);
+		return EXIT_KERNEL_BIND;
+	}
+
+	opt = addr.nl_groups;
+	r = setsockopt(cn_fd, 270, NETLINK_ADD_MEMBERSHIP, &opt, sizeof(opt));
+	if (r) {
+		close(cn_fd);
+		return EXIT_KERNEL_SETSOCKOPT;
+	}
+
+	/*
+	r = fcntl(cn_fd, F_SETFL, FNDELAY);
+	*/
+
+	links_register(cn_fd, "local", do_local_work, NULL);
+
+	return 0;
+}
+
+/*
+ * cleanup_local
+ *
+ * Clean up before exiting
+ */
+void cleanup_local(void)
+{
+	links_unregister(cn_fd);
+	close(cn_fd);
+}

daemons/cmirrord/local.h

@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#ifndef _LVM_CLOG_LOCAL_H
+#define _LVM_CLOG_LOCAL_H
+
+int init_local(void);
+void cleanup_local(void);
+
+int kernel_send(struct dm_ulog_request *rq);
+
+#endif /* _LVM_CLOG_LOCAL_H */

daemons/cmirrord/logging.c

@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#include "logging.h"
+
+const char *__rq_types_off_by_one[] = {
+	"DM_ULOG_CTR",
+	"DM_ULOG_DTR",
+	"DM_ULOG_PRESUSPEND",
+	"DM_ULOG_POSTSUSPEND",
+	"DM_ULOG_RESUME",
+	"DM_ULOG_GET_REGION_SIZE",
+	"DM_ULOG_IS_CLEAN",
+	"DM_ULOG_IN_SYNC",
+	"DM_ULOG_FLUSH",
+	"DM_ULOG_MARK_REGION",
+	"DM_ULOG_CLEAR_REGION",
+	"DM_ULOG_GET_RESYNC_WORK",
+	"DM_ULOG_SET_REGION_SYNC",
+	"DM_ULOG_GET_SYNC_COUNT",
+	"DM_ULOG_STATUS_INFO",
+	"DM_ULOG_STATUS_TABLE",
+	"DM_ULOG_IS_REMOTE_RECOVERING",
+	NULL
+};
+
+int log_tabbing = 0;
+int log_is_open = 0;
+
+/*
+ * Variables for various conditional logging
+ */
+#ifdef MEMB
+int log_membership_change = 1;
+#else
+int log_membership_change = 0;
+#endif
+
+#ifdef CKPT
+int log_checkpoint = 1;
+#else
+int log_checkpoint = 0;
+#endif
+
+#ifdef RESEND
+int log_resend_requests = 1;
+#else
+int log_resend_requests = 0;
+#endif

daemons/cmirrord/logging.h

@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _LVM_CLOG_LOGGING_H
+#define _LVM_CLOG_LOGGING_H
+
+#define _GNU_SOURCE
+#define _FILE_OFFSET_BITS 64
+
+#include "configure.h"
+#include <stdio.h>
+#include <stdint.h>
+#include <syslog.h>
+
+/* SHORT_UUID - print last 8 chars of a string */
+#define SHORT_UUID(x) (strlen(x) > 8) ? ((x) + (strlen(x) - 8)) : (x)
+
+extern const char *__rq_types_off_by_one[];
+#define RQ_TYPE(x) __rq_types_off_by_one[(x) - 1]
+
+extern int log_tabbing;
+extern int log_is_open;
+extern int log_membership_change;
+extern int log_checkpoint;
+extern int log_resend_requests;
+
+#define LOG_OPEN(ident, option, facility) do { \
+		openlog(ident, option, facility); \
+		log_is_open = 1;		  \
+	} while (0)
+
+#define LOG_CLOSE(void) do { \
+		log_is_open = 0; \
+		closelog();	 \
+	} while (0)
+
+#define LOG_OUTPUT(level, f, arg...) do {				\
+		int __i;						\
+		char __buffer[16];					\
+		FILE *fp = (level > LOG_NOTICE) ? stderr : stdout;	\
+		if (log_is_open) {					\
+			for (__i = 0; (__i < log_tabbing) && (__i < 15); __i++) \
+				__buffer[__i] = '\t';			\
+			__buffer[__i] = '\0';				\
+			syslog(level, "%s" f "\n", __buffer, ## arg);	\
+		} else {						\
+			for (__i = 0; __i < log_tabbing; __i++)		\
+				fprintf(fp, "\t");			\
+			fprintf(fp, f "\n", ## arg);			\
+		}							\
+	} while (0)
+
+
+#ifdef DEBUG
+#define LOG_DBG(f, arg...) LOG_OUTPUT(LOG_DEBUG, f, ## arg)
+#else /* DEBUG */
+#define LOG_DBG(f, arg...)
+#endif /* DEBUG */
+
+#define LOG_COND(__X, f, arg...) do {\
+		if (__X) { 	     \
+			LOG_OUTPUT(LOG_NOTICE, f, ## arg); \
+		} \
+	} while (0)
+#define LOG_PRINT(f, arg...) LOG_OUTPUT(LOG_NOTICE, f, ## arg)
+#define LOG_ERROR(f, arg...) LOG_OUTPUT(LOG_ERR, f, ## arg)
+
+#endif /* _LVM_CLOG_LOGGING_H */

daemons/common/Makefile.in

@@ -0,0 +1,22 @@
+# Copyright (C) 2011 Red Hat, Inc. All rights reserved.
+#
+# This file is part of the device-mapper userspace tools.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU Lesser General Public License v.2.1.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+LIB_STATIC = libdaemon.a
+SOURCES = daemon-shared.c daemon-server.c daemon-client.c
+
+include $(top_builddir)/make.tmpl
+
+device-mapper: $(LIB_STATIC)

daemons/common/daemon-client.c

@@ -0,0 +1,81 @@
+#include "daemon-client.h"
+#include "daemon-shared.h"
+#include <sys/un.h>
+#include <sys/socket.h>
+#include <string.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <assert.h>
+#include <errno.h> // ENOMEM
+
+daemon_handle daemon_open(daemon_info i) {
+	daemon_handle h = { .protocol = 0 };
+	struct sockaddr_un sockaddr;
+
+	if ((h.socket_fd = socket(PF_UNIX, SOCK_STREAM /* | SOCK_NONBLOCK */, 0)) < 0) {
+		perror("socket");
+		goto error;
+	}
+	memset(&sockaddr, 0, sizeof(sockaddr));
+	fprintf(stderr, "[C] connecting to %s\n", i.socket);
+	strcpy(sockaddr.sun_path, i.socket);
+	sockaddr.sun_family = AF_UNIX;
+	if (connect(h.socket_fd,(struct sockaddr *) &sockaddr, sizeof(sockaddr))) {
+		perror("connect");
+		goto error;
+	}
+	return h;
+error:
+	if (h.socket_fd >= 0)
+		close(h.socket_fd);
+	h.socket_fd = -1;
+	return h;
+}
+
+daemon_reply daemon_send(daemon_handle h, daemon_request rq)
+{
+	daemon_reply reply = { .cft = NULL, .error = 0 };
+	assert(h.socket_fd >= 0);
+
+	if (!rq.buffer) {
+		/* TODO: build the buffer from rq.cft */
+	}
+
+	assert(rq.buffer);
+	write_buffer(h.socket_fd, rq.buffer, strlen(rq.buffer));
+
+	if (read_buffer(h.socket_fd, &reply.buffer)) {
+		reply.cft = dm_config_from_string(reply.buffer);
+	} else
+		reply.error = 1;
+
+	return reply;
+}
+
+void daemon_reply_destroy(daemon_reply r) {
+	if (r.cft)
+		dm_config_destroy(r.cft);
+}
+
+daemon_reply daemon_send_simple(daemon_handle h, const char *id, ...)
+{
+	static const daemon_reply err = { .error = ENOMEM, .buffer = NULL, .cft = NULL };
+	daemon_request rq = { .cft = NULL };
+	daemon_reply repl;
+	va_list ap;
+
+	va_start(ap, id);
+	rq.buffer = format_buffer("request", id, ap);
+	va_end(ap);
+
+	if (!rq.buffer)
+		return err;
+
+	repl = daemon_send(h, rq);
+	dm_free(rq.buffer);
+	return repl;
+}
+
+void daemon_close(daemon_handle h)
+{
+}

daemons/common/daemon-client.h

@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2011 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "libdevmapper.h" // for dm_list, needed by config.h
+
+#ifndef _LVM_DAEMON_COMMON_CLIENT_H
+#define _LVM_DAEMON_COMMON_CLIENT_H
+
+typedef struct {
+	int socket_fd; /* the fd we use to talk to the daemon */
+	int protocol;  /* version of the protocol the daemon uses */
+} daemon_handle;
+
+typedef struct {
+	const char *path; /* the binary of the daemon */
+	const char *socket; /* path to the comms socket */
+	unsigned autostart:1; /* start the daemon if not running? */
+} daemon_info;
+
+typedef struct {
+	char *buffer;
+	/*
+	 * The request looks like this:
+	 *    request = "id"
+	 *    arg_foo = "something"
+	 *    arg_bar = 3
+	 *    arg_wibble {
+	 *        something_special = "here"
+	 *        amount = 75
+	 *        knobs = [ "twiddle", "tweak" ]
+	 *    }
+	 */
+	struct dm_config_tree *cft;
+} daemon_request;
+
+typedef struct {
+	int error; /* 0 for success */
+	char *buffer; /* textual reply */
+	struct dm_config_tree *cft; /* parsed reply, if available */
+} daemon_reply;
+
+/*
+ * Open the communication channel to the daemon. If the daemon is not running,
+ * it may be autostarted based on the binary path provided in the info (this
+ * will only happen if autostart is set to true). If the call fails for any
+ * reason, daemon_handle_valid(h) for the response will return false. Otherwise,
+ * the connection is good to start serving requests.
+ */
+daemon_handle daemon_open(daemon_info i);
+
+/*
+ * Send a request to the daemon, waiting for the reply. All communication with
+ * the daemon is synchronous. The function handles the IO details and parses the
+ * response, handling common error conditions. See "daemon_reply" for details.
+ *
+ * In case the request contains a non-NULL buffer pointer, this buffer is sent
+ * *verbatim* to the server. In this case, the cft pointer may be NULL (but will
+ * be ignored even if non-NULL). If the buffer is NULL, the cft is required to
+ * be a valid pointer, and is used to build up the request.
+ */
+daemon_reply daemon_send(daemon_handle h, daemon_request r);
+
+/*
+ * A simple interface to daemon_send. This function just takes the command id
+ * and possibly a list of parameters (of the form "name = %?", "value"). The
+ * type (string, integer) of the value is indicated by a character substituted
+ * for ? in %?: d for integer, s for string.
+ */
+daemon_reply daemon_send_simple(daemon_handle h, const char *id, ...);
+
+void daemon_reply_destroy(daemon_reply r);
+
+static inline int daemon_reply_int(daemon_reply r, const char *path, int def) {
+	return dm_config_find_int(r.cft->root, path, def);
+}
+
+static inline const char *daemon_reply_str(daemon_reply r, const char *path, const char *def) {
+	return dm_config_find_str(r.cft->root, path, def);
+}
+
+
+/* Shut down the communication to the daemon. Compulsory. */
+void daemon_close(daemon_handle h);
+
+#endif

daemons/common/daemon-server.c

@@ -0,0 +1,380 @@
+/*
+ * Copyright (C) 2011 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <dlfcn.h>
+#include <errno.h>
+#include <pthread.h>
+#include <sys/file.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <netinet/in.h>
+#include <sys/un.h>
+#include <unistd.h>
+#include <signal.h>
+
+#include <syslog.h>
+#include "daemon-server.h"
+#include "daemon-shared.h"
+#include "libdevmapper.h"
+
+#if 0
+/* Create a device monitoring thread. */
+static int _pthread_create(pthread_t *t, void *(*fun)(void *), void *arg, int stacksize)
+{
+	pthread_attr_t attr;
+	pthread_attr_init(&attr);
+	/*
+	 * We use a smaller stack since it gets preallocated in its entirety
+	 */
+	pthread_attr_setstacksize(&attr, stacksize);
+	return pthread_create(t, &attr, fun, arg);
+}
+#endif
+
+static volatile sig_atomic_t _shutdown_requested = 0;
+
+static void _exit_handler(int sig __attribute__((unused)))
+{
+	_shutdown_requested = 1;
+}
+
+#ifdef linux
+#  define OOM_ADJ_FILE "/proc/self/oom_adj"
+#  include <stdio.h>
+
+/* From linux/oom.h */
+#  define OOM_DISABLE (-17)
+#  define OOM_ADJUST_MIN (-16)
+
+/*
+ * Protection against OOM killer if kernel supports it
+ */
+static int _set_oom_adj(int val)
+{
+	FILE *fp;
+
+	struct stat st;
+
+	if (stat(OOM_ADJ_FILE, &st) == -1) {
+		if (errno == ENOENT)
+			perror(OOM_ADJ_FILE " not found");
+		else
+			perror(OOM_ADJ_FILE ": stat failed");
+		return 1;
+	}
+
+	if (!(fp = fopen(OOM_ADJ_FILE, "w"))) {
+		perror(OOM_ADJ_FILE ": fopen failed");
+		return 0;
+	}
+
+	fprintf(fp, "%i", val);
+	if (fclose(fp))
+		perror(OOM_ADJ_FILE ": fclose failed");
+
+	return 1;
+}
+#endif
+
+static int _open_socket(daemon_state s)
+{
+	int fd = -1;
+	struct sockaddr_un sockaddr;
+	mode_t old_mask;
+
+	(void) dm_prepare_selinux_context(s.socket_path, S_IFSOCK);
+	old_mask = umask(0077);
+
+	/* Open local socket */
+	fd = socket(PF_UNIX, SOCK_STREAM, 0);
+	if (fd < 0) {
+		perror("Can't create local socket.");
+		goto error;
+	}
+
+	/* Set Close-on-exec & non-blocking */
+	if (fcntl(fd, F_SETFD, 1))
+		fprintf(stderr, "setting CLOEXEC on socket fd %d failed: %s\n", fd, strerror(errno));
+	fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) | O_NONBLOCK);
+
+	fprintf(stderr, "[D] creating %s\n", s.socket_path);
+	memset(&sockaddr, 0, sizeof(sockaddr));
+	strcpy(sockaddr.sun_path, s.socket_path);
+	sockaddr.sun_family = AF_UNIX;
+
+	if (bind(fd, (struct sockaddr *) &sockaddr, sizeof(sockaddr))) {
+		perror("can't bind local socket.");
+		goto error;
+	}
+	if (listen(fd, 1) != 0) {
+		perror("listen local");
+		goto error;
+	}
+
+out:
+	umask(old_mask);
+	(void) dm_prepare_selinux_context(NULL, 0);
+	return fd;
+
+error:
+	if (fd >= 0) {
+		if (close(fd))
+			perror("close failed");
+		if (unlink(s.socket_path))
+			perror("unlink failed");
+		fd = -1;
+	}
+	goto out;
+}
+
+static void remove_lockfile(const char *file)
+{
+	if (unlink(file))
+		perror("unlink failed");
+}
+
+static void _daemonise(void)
+{
+	int child_status;
+	int fd;
+	pid_t pid;
+	struct rlimit rlim;
+	struct timeval tval;
+	sigset_t my_sigset;
+
+	sigemptyset(&my_sigset);
+	if (sigprocmask(SIG_SETMASK, &my_sigset, NULL) < 0) {
+		fprintf(stderr, "Unable to restore signals.\n");
+		exit(EXIT_FAILURE);
+	}
+	signal(SIGTERM, &_exit_handler);
+
+	switch (pid = fork()) {
+	case -1:
+		perror("fork failed:");
+		exit(EXIT_FAILURE);
+
+	case 0:		/* Child */
+		break;
+
+	default:
+		/* Wait for response from child */
+		while (!waitpid(pid, &child_status, WNOHANG) && !_shutdown_requested) {
+			tval.tv_sec = 0;
+			tval.tv_usec = 250000;	/* .25 sec */
+			select(0, NULL, NULL, NULL, &tval);
+		}
+
+		if (_shutdown_requested) /* Child has signaled it is ok - we can exit now */
+			exit(0);
+
+		/* Problem with child.  Determine what it is by exit code */
+		fprintf(stderr, "Child exited with code %d\n", WEXITSTATUS(child_status));
+		exit(WEXITSTATUS(child_status));
+	}
+
+	if (chdir("/"))
+		exit(1);
+
+	if (getrlimit(RLIMIT_NOFILE, &rlim) < 0)
+		fd = 256; /* just have to guess */
+	else
+		fd = rlim.rlim_cur;
+
+	for (--fd; fd >= 0; fd--)
+		close(fd);
+
+	if ((open("/dev/null", O_RDONLY) < 0) ||
+	    (open("/dev/null", O_WRONLY) < 0) ||
+	    (open("/dev/null", O_WRONLY) < 0))
+		exit(1);
+
+	setsid();
+}
+
+response daemon_reply_simple(const char *id, ...)
+{
+	va_list ap;
+	response res = { .cft = NULL };
+
+	va_start(ap, id);
+
+	if (!(res.buffer = format_buffer("response", id, ap)))
+		res.error = ENOMEM;
+
+	va_end(ap);
+
+	return res;
+}
+
+struct thread_baton {
+	daemon_state s;
+	client_handle client;
+};
+
+static int buffer_rewrite(char **buf, const char *format, const char *string) {
+	char *old = *buf;
+	dm_asprintf(buf, format, *buf, string);
+	dm_free(old);
+	return 0;
+}
+
+static int buffer_line(const char *line, void *baton) {
+	response *r = baton;
+	if (r->buffer)
+		buffer_rewrite(&r->buffer, "%s\n%s", line);
+	else
+		dm_asprintf(&r->buffer, "%s\n", line);
+	return 0;
+}
+
+static void *client_thread(void *baton)
+{
+	struct thread_baton *b = baton;
+	request req;
+	response res;
+
+	while (1) {
+		if (!read_buffer(b->client.socket_fd, &req.buffer))
+			goto fail;
+
+		req.cft = dm_config_from_string(req.buffer);
+		if (!req.cft)
+			fprintf(stderr, "error parsing request:\n %s\n", req.buffer);
+		res = b->s.handler(b->s, b->client, req);
+
+		if (!res.buffer) {
+			dm_config_write_node(res.cft->root, buffer_line, &res);
+			buffer_rewrite(&res.buffer, "%s\n\n", NULL);
+			dm_config_destroy(res.cft);
+		}
+
+		if (req.cft)
+			dm_config_destroy(req.cft);
+		dm_free(req.buffer);
+
+		write_buffer(b->client.socket_fd, res.buffer, strlen(res.buffer));
+
+		free(res.buffer);
+	}
+fail:
+	/* TODO what should we really do here? */
+	close(b->client.socket_fd);
+	free(baton);
+	return NULL;
+}
+
+static int handle_connect(daemon_state s)
+{
+	struct thread_baton *baton;
+	struct sockaddr_un sockaddr;
+	client_handle client = { .thread_id = 0 };
+	socklen_t sl = sizeof(sockaddr);
+
+	client.socket_fd = accept(s.socket_fd, (struct sockaddr *) &sockaddr, &sl);
+	if (client.socket_fd < 0)
+		return 0;
+
+	if (!(baton = malloc(sizeof(struct thread_baton))))
+		return 0;
+
+	baton->s = s;
+	baton->client = client;
+
+	if (pthread_create(&baton->client.thread_id, NULL, client_thread, baton))
+		return 0;
+
+	pthread_detach(baton->client.thread_id);
+
+	return 1;
+}
+
+void daemon_start(daemon_state s)
+{
+	int failed = 0;
+	/*
+	 * Switch to C locale to avoid reading large locale-archive file used by
+	 * some glibc (on some distributions it takes over 100MB). Some daemons
+	 * need to use mlockall().
+	 */
+	if (setenv("LANG", "C", 1))
+		perror("Cannot set LANG to C");
+
+	if (!s.foreground)
+		_daemonise();
+
+	/* TODO logging interface should be somewhat more elaborate */
+	openlog(s.name, LOG_PID, LOG_DAEMON);
+
+	(void) dm_prepare_selinux_context(s.pidfile, S_IFREG);
+
+	/*
+	 * NB. Take care to not keep stale locks around. Best not exit(...)
+	 * after this point.
+	 */
+	if (dm_create_lockfile(s.pidfile) == 0)
+		exit(1);
+
+	(void) dm_prepare_selinux_context(NULL, 0);
+
+	/* Set normal exit signals to request shutdown instead of dying. */
+	signal(SIGINT, &_exit_handler);
+	signal(SIGHUP, &_exit_handler);
+	signal(SIGQUIT, &_exit_handler);
+	signal(SIGTERM, &_exit_handler);
+	signal(SIGALRM, &_exit_handler);
+	signal(SIGPIPE, SIG_IGN);
+
+#ifdef linux
+	if (s.avoid_oom && !_set_oom_adj(OOM_DISABLE) && !_set_oom_adj(OOM_ADJUST_MIN))
+		syslog(LOG_ERR, "Failed to set oom_adj to protect against OOM killer");
+#endif
+
+	if (s.socket_path) {
+		s.socket_fd = _open_socket(s);
+		if (s.socket_fd < 0)
+			failed = 1;
+	}
+
+	/* Signal parent, letting them know we are ready to go. */
+	if (!s.foreground)
+		kill(getppid(), SIGTERM);
+
+	if (s.daemon_init)
+		s.daemon_init(&s);
+
+	while (!_shutdown_requested && !failed) {
+		fd_set in;
+		FD_ZERO(&in);
+		FD_SET(s.socket_fd, &in);
+		if (select(FD_SETSIZE, &in, NULL, NULL, NULL) < 0 && errno != EINTR)
+			perror("select error");
+		if (FD_ISSET(s.socket_fd, &in))
+			if (!handle_connect(s))
+				syslog(LOG_ERR, "Failed to handle a client connection.");
+	}
+
+	if (s.socket_fd >= 0)
+		if (unlink(s.socket_path))
+			perror("unlink error");
+
+	if (s.daemon_fini)
+		s.daemon_fini(&s);
+
+	syslog(LOG_NOTICE, "%s shutting down", s.name);
+	closelog();
+	remove_lockfile(s.pidfile);
+	if (failed)
+		exit(1);
+}

daemons/common/daemon-server.h

@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 2011 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "daemon-client.h"
+
+#ifndef _LVM_DAEMON_COMMON_SERVER_H
+#define _LVM_DAEMON_COMMON_SERVER_H
+
+typedef struct {
+	int socket_fd; /* the fd we use to talk to the client */
+	pthread_t thread_id;
+	char *read_buf;
+	void *private; /* this holds per-client state */
+} client_handle;
+
+typedef struct {
+	struct dm_config_tree *cft;
+	char *buffer;
+} request;
+
+typedef struct {
+	int error;
+	struct dm_config_tree *cft;
+	char *buffer;
+} response;
+
+struct daemon_state;
+
+/*
+ * Craft a simple reply, without the need to construct a config_tree. See
+ * daemon_send_simple in daemon-client.h for the description of the parameters.
+ */
+response daemon_reply_simple(const char *id, ...);
+
+static inline int daemon_request_int(request r, const char *path, int def) {
+	if (!r.cft)
+		return def;
+	return dm_config_find_int(r.cft->root, path, def);
+}
+
+static inline const char *daemon_request_str(request r, const char *path, const char *def) {
+	if (!r.cft)
+		return def;
+	return dm_config_find_str(r.cft->root, path, def);
+}
+
+/*
+ * The callback. Called once per request issued, in the respective client's
+ * thread. It is presented by a parsed request (in the form of a config tree).
+ * The output is a new config tree that is serialised and sent back to the
+ * client. The client blocks until the request processing is done and reply is
+ * sent.
+ */
+typedef response (*handle_request)(struct daemon_state s, client_handle h, request r);
+
+typedef struct daemon_state {
+	/*
+	 * The maximal stack size for individual daemon threads. This is
+	 * essential for daemons that need to be locked into memory, since
+	 * pthread's default is 10M per thread.
+	 */
+	int thread_stack_size;
+
+	/* Flags & attributes affecting the behaviour of the daemon. */
+	unsigned avoid_oom:1;
+	unsigned foreground:1;
+	const char *name;
+	const char *pidfile;
+	const char *socket_path;
+	int log_level;
+	handle_request handler;
+	int (*daemon_init)(struct daemon_state *st);
+	int (*daemon_fini)(struct daemon_state *st);
+
+	/* Global runtime info maintained by the framework. */
+	int socket_fd;
+
+	void *private; /* the global daemon state */
+} daemon_state;
+
+/*
+ * Start serving the requests. This does all the daemonisation, socket setup
+ * work and so on. This function takes over the process, and upon failure, it
+ * will terminate execution. It may be called at most once.
+ */
+void daemon_start(daemon_state s);
+
+/*
+ * Take over from an already running daemon. This function handles connecting
+ * to the running daemon and telling it we are going to take over. The takeover
+ * request may be customised by passing in a non-NULL request.
+ *
+ * The takeover sequence: the old daemon stops accepting new clients, then it
+ * waits until all current client connections are closed. When that happens, it
+ * serializes its current state and sends that as a reply, which is then
+ * returned by this function (therefore, this function won't return until the
+ * previous instance has shut down).
+ *
+ * The daemon, after calling daemon_takeover is expected to set up its
+ * daemon_state using the reply from this function and call daemon_start as
+ * usual.
+ */
+daemon_reply daemon_takeover(daemon_info i, daemon_request r);
+
+/* Call this to request a clean shutdown of the daemon. Async safe. */
+void daemon_stop(void);
+
+#endif

daemons/common/daemon-shared.c

@@ -0,0 +1,123 @@
+#include <errno.h>
+#include <stdio.h>
+#include <malloc.h>
+#include <string.h>
+#include <unistd.h>
+#include <assert.h>
+#include "daemon-shared.h"
+
+/*
+ * Read a single message from a (socket) filedescriptor. Messages are delimited
+ * by blank lines. This call will block until all of a message is received. The
+ * memory will be allocated from heap. Upon error, all memory is freed and the
+ * buffer pointer is set to NULL.
+ *
+ * See also write_buffer about blocking (read_buffer has identical behaviour).
+ */
+int read_buffer(int fd, char **buffer) {
+	int bytes = 0;
+	int buffersize = 32;
+	char *new;
+	*buffer = malloc(buffersize + 1);
+
+	while (1) {
+		int result = read(fd, (*buffer) + bytes, buffersize - bytes);
+		if (result > 0)
+			bytes += result;
+		if (result == 0)
+			goto fail; /* we should never encounter EOF here */
+		if (result < 0 && errno != EAGAIN && errno != EWOULDBLOCK)
+			goto fail;
+
+		if ((!strncmp((*buffer) + bytes - 4, "\n##\n", 4))) {
+			*(*buffer + bytes - 4) = 0;
+			break; /* success, we have the full message now */
+		}
+
+		if (bytes == buffersize) {
+			buffersize += 1024;
+			if (!(new = realloc(*buffer, buffersize + 1)))
+				goto fail;
+
+			*buffer = new;
+		}
+		/* TODO call select here if we encountered EAGAIN/EWOULDBLOCK */
+	}
+	return 1;
+fail:
+	free(*buffer);
+	*buffer = NULL;
+	return 0;
+}
+
+/*
+ * Write a buffer to a filedescriptor. Keep trying. Blocks (even on
+ * SOCK_NONBLOCK) until all of the write went through.
+ *
+ * TODO use select on EWOULDBLOCK/EAGAIN to avoid useless spinning
+ */
+int write_buffer(int fd, const char *buffer, int length) {
+	static const char terminate[] = "\n##\n";
+	int done = 0;
+	int written = 0;
+write:
+	while (1) {
+		int result = write(fd, buffer + written, length - written);
+		if (result > 0)
+			written += result;
+		if (result < 0 && errno != EWOULDBLOCK && errno != EAGAIN)
+			return 0; /* too bad */
+		if (written == length) {
+			if (done)
+				return 1;
+			else
+				break; /* done */
+		}
+	}
+
+	buffer = terminate;
+	length = 4;
+	written = 0;
+	done = 1;
+	goto write;
+}
+
+char *format_buffer(const char *what, const char *id, va_list ap)
+{
+	char *buffer, *old;
+	char *next;
+	int keylen;
+
+	dm_asprintf(&buffer, "%s = \"%s\"\n", what, id);
+	if (!buffer) goto fail;
+
+	while ((next = va_arg(ap, char *))) {
+		old = buffer;
+		assert(strchr(next, '='));
+		keylen = strchr(next, '=') - next;
+		if (strstr(next, "%d")) {
+			int value = va_arg(ap, int);
+			dm_asprintf(&buffer, "%s%.*s= %d\n", buffer, keylen, next, value);
+			dm_free(old);
+		} else if (strstr(next, "%s")) {
+			char *value = va_arg(ap, char *);
+			dm_asprintf(&buffer, "%s%.*s= \"%s\"\n", buffer, keylen, next, value);
+			dm_free(old);
+		} else if (strstr(next, "%b")) {
+			char *block = va_arg(ap, char *);
+			if (!block)
+				continue;
+			dm_asprintf(&buffer, "%s%.*s%s", buffer, keylen, next, block);
+			dm_free(old);
+		} else {
+			dm_asprintf(&buffer, "%s%s", buffer, next);
+			dm_free(old);
+		}
+		if (!buffer) goto fail;
+	}
+
+	return buffer;
+fail:
+	dm_free(buffer);
+	return NULL;
+}

daemons/common/daemon-shared.h

@@ -0,0 +1,6 @@
+#include <stdarg.h>
+#include <libdevmapper.h>
+
+int read_buffer(int fd, char **buffer);
+int write_buffer(int fd, const char *buffer, int length);
+char *format_buffer(const char *what, const char *id, va_list ap);

daemons/dmeventd/.exported_symbols

@@ -0,0 +1,4 @@
+init_fifos
+fini_fifos
+daemon_talk
+dm_event_get_version

daemons/dmeventd/Makefile.in

@@ -0,0 +1,108 @@
+#
+# Copyright (C) 2005-2011 Red Hat, Inc. All rights reserved.
+#
+# This file is part of the device-mapper userspace tools.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU Lesser General Public License v.2.1.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+SOURCES = libdevmapper-event.c
+SOURCES2 = dmeventd.c
+
+TARGETS = dmeventd
+
+.PHONY: install_lib_dynamic install_lib_static install_include \
+	install_pkgconfig install_dmeventd_dynamic install_dmeventd_static \
+	install_lib install_dmeventd
+
+INSTALL_DMEVENTD_TARGETS = install_dmeventd_dynamic
+INSTALL_LIB_TARGETS = install_lib_dynamic
+
+LIB_NAME = libdevmapper-event
+ifeq ("@STATIC_LINK@", "yes")
+  LIB_STATIC = $(LIB_NAME).a
+  TARGETS += $(LIB_STATIC) dmeventd.static
+  INSTALL_DMEVENTD_TARGETS += install_dmeventd_static
+  INSTALL_LIB_TARGETS += install_lib_static
+endif
+
+LIB_VERSION = $(LIB_VERSION_DM)
+LIB_SHARED = $(LIB_NAME).$(LIB_SUFFIX)
+
+CLEAN_TARGETS = dmeventd.static $(LIB_NAME).a
+
+ifneq ($(MAKECMDGOALS),device-mapper)
+  SUBDIRS+=plugins
+endif
+
+CFLOW_LIST = $(SOURCES)
+CFLOW_LIST_TARGET = $(LIB_NAME).cflow
+CFLOW_TARGET = dmeventd
+
+EXPORTED_HEADER = $(srcdir)/libdevmapper-event.h
+EXPORTED_FN_PREFIX = dm_event
+
+include $(top_builddir)/make.tmpl
+
+all: device-mapper
+device-mapper: $(TARGETS)
+
+LIBS += -ldevmapper
+LVMLIBS += -ldevmapper-event $(PTHREAD_LIBS)
+
+dmeventd: $(LIB_SHARED) dmeventd.o
+	$(CC) $(CFLAGS) $(LDFLAGS) $(ELDFLAGS) -L. -o $@ dmeventd.o \
+	$(DL_LIBS) $(LVMLIBS) $(LIBS) -rdynamic
+
+dmeventd.static: $(LIB_STATIC) dmeventd.o $(interfacebuilddir)/libdevmapper.a
+	$(CC) $(CFLAGS) $(LDFLAGS) $(ELDFLAGS) -static -L. -L$(interfacebuilddir) -o $@ \
+	dmeventd.o $(DL_LIBS) $(LVMLIBS) $(LIBS) $(STATIC_LIBS)
+
+ifeq ("@PKGCONFIG@", "yes")
+  INSTALL_LIB_TARGETS += install_pkgconfig
+endif
+
+ifneq ("$(CFLOW_CMD)", "")
+CFLOW_SOURCES = $(addprefix $(srcdir)/, $(SOURCES))
+-include $(top_builddir)/libdm/libdevmapper.cflow
+-include $(top_builddir)/lib/liblvm-internal.cflow
+-include $(top_builddir)/lib/liblvm2cmd.cflow
+-include $(top_builddir)/daemons/dmeventd/$(LIB_NAME).cflow
+-include $(top_builddir)/daemons/dmeventd/plugins/mirror/$(LIB_NAME)-lvm2mirror.cflow
+endif
+
+install_include: $(srcdir)/libdevmapper-event.h
+	$(INSTALL_DATA) -D $< $(includedir)/$(<F)
+
+install_pkgconfig: libdevmapper-event.pc
+	$(INSTALL_DATA) -D $< $(pkgconfigdir)/devmapper-event.pc
+
+install_lib_dynamic: install_lib_shared
+
+install_lib_static: $(LIB_STATIC)
+	$(INSTALL_DATA) -D $< $(usrlibdir)/$(<F)
+
+install_lib: $(INSTALL_LIB_TARGETS)
+
+install_dmeventd_dynamic: dmeventd
+	$(INSTALL_PROGRAM) -D $< $(sbindir)/$(<F)
+
+install_dmeventd_static: dmeventd.static
+	$(INSTALL_PROGRAM) -D $< $(staticdir)/$(<F)
+
+install_dmeventd: $(INSTALL_DMEVENTD_TARGETS)
+
+install: install_include install_lib install_dmeventd
+
+install_device-mapper: install_include install_lib install_dmeventd
+
+DISTCLEAN_TARGETS += libdevmapper-event.pc

daemons/dmeventd/dmeventd.h

@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2005-2007 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of the device-mapper userspace tools.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef __DMEVENTD_DOT_H__
+#define __DMEVENTD_DOT_H__
+
+/* FIXME This stuff must be configurable. */
+
+#define	DM_EVENT_FIFO_CLIENT	"/var/run/dmeventd-client"
+#define	DM_EVENT_FIFO_SERVER	"/var/run/dmeventd-server"
+
+#define DM_EVENT_DEFAULT_TIMEOUT 10
+
+/* Commands for the daemon passed in the message below. */
+enum dm_event_command {
+	DM_EVENT_CMD_ACTIVE = 1,
+	DM_EVENT_CMD_REGISTER_FOR_EVENT,
+	DM_EVENT_CMD_UNREGISTER_FOR_EVENT,
+	DM_EVENT_CMD_GET_REGISTERED_DEVICE,
+	DM_EVENT_CMD_GET_NEXT_REGISTERED_DEVICE,
+	DM_EVENT_CMD_SET_TIMEOUT,
+	DM_EVENT_CMD_GET_TIMEOUT,
+	DM_EVENT_CMD_HELLO,
+	DM_EVENT_CMD_DIE,
+	DM_EVENT_CMD_GET_STATUS,
+};
+
+/* Message passed between client and daemon. */
+struct dm_event_daemon_message {
+	uint32_t cmd;
+	uint32_t size;
+	char *data;
+};
+
+/* FIXME Is this meant to be exported?  I can't see where the
+   interface uses it. */
+/* Fifos for client/daemon communication. */
+struct dm_event_fifos {
+	int client;
+	int server;
+	const char *client_path;
+	const char *server_path;
+};
+
+/*      EXIT_SUCCESS             0 -- stdlib.h */
+/*      EXIT_FAILURE             1 -- stdlib.h */
+/*      EXIT_LOCKFILE_INUSE      2 -- obsoleted */
+#define EXIT_DESC_CLOSE_FAILURE  3
+#define EXIT_DESC_OPEN_FAILURE   4
+/*      EXIT_OPEN_PID_FAILURE    5 -- obsoleted */
+#define EXIT_FIFO_FAILURE        6
+#define EXIT_CHDIR_FAILURE       7
+
+/* Implemented in libdevmapper-event.c, but not part of public API. */
+int daemon_talk(struct dm_event_fifos *fifos,
+		struct dm_event_daemon_message *msg, int cmd,
+		const char *dso_name, const char *dev_name,
+		enum dm_event_mask evmask, uint32_t timeout);
+int init_fifos(struct dm_event_fifos *fifos);
+void fini_fifos(struct dm_event_fifos *fifos);
+int dm_event_get_version(struct dm_event_fifos *fifos, int *version);
+
+#endif /* __DMEVENTD_DOT_H__ */

daemons/dmeventd/libdevmapper-event.c

@@ -0,0 +1,878 @@
+/*
+ * Copyright (C) 2005-2007 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of the device-mapper userspace tools.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "dmlib.h"
+#include "libdevmapper-event.h"
+//#include "libmultilog.h"
+#include "dmeventd.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/file.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <sys/wait.h>
+#include <arpa/inet.h>		/* for htonl, ntohl */
+
+static int _sequence_nr = 0;
+
+struct dm_event_handler {
+	char *dso;
+
+	char *dmeventd_path;
+
+	char *dev_name;
+
+	char *uuid;
+	int major;
+	int minor;
+	uint32_t timeout;
+
+	enum dm_event_mask mask;
+};
+
+static void _dm_event_handler_clear_dev_info(struct dm_event_handler *dmevh)
+{
+	dm_free(dmevh->dev_name);
+	dm_free(dmevh->uuid);
+	dmevh->dev_name = dmevh->uuid = NULL;
+	dmevh->major = dmevh->minor = 0;
+}
+
+struct dm_event_handler *dm_event_handler_create(void)
+{
+	struct dm_event_handler *dmevh = NULL;
+
+	if (!(dmevh = dm_malloc(sizeof(*dmevh))))
+		return NULL;
+
+	dmevh->dmeventd_path = NULL;
+	dmevh->dso = dmevh->dev_name = dmevh->uuid = NULL;
+	dmevh->major = dmevh->minor = 0;
+	dmevh->mask = 0;
+	dmevh->timeout = 0;
+
+	return dmevh;
+}
+
+void dm_event_handler_destroy(struct dm_event_handler *dmevh)
+{
+	_dm_event_handler_clear_dev_info(dmevh);
+	dm_free(dmevh->dso);
+	dm_free(dmevh->dmeventd_path);
+	dm_free(dmevh);
+}
+
+int dm_event_handler_set_dmeventd_path(struct dm_event_handler *dmevh, const char *dmeventd_path)
+{
+	if (!dmeventd_path) /* noop */
+		return 0;
+
+	dm_free(dmevh->dmeventd_path);
+
+	dmevh->dmeventd_path = dm_strdup(dmeventd_path);
+	if (!dmevh->dmeventd_path)
+		return -ENOMEM;
+
+	return 0;
+}
+
+int dm_event_handler_set_dso(struct dm_event_handler *dmevh, const char *path)
+{
+	if (!path) /* noop */
+		return 0;
+	dm_free(dmevh->dso);
+
+	dmevh->dso = dm_strdup(path);
+	if (!dmevh->dso)
+		return -ENOMEM;
+
+	return 0;
+}
+
+int dm_event_handler_set_dev_name(struct dm_event_handler *dmevh, const char *dev_name)
+{
+	if (!dev_name)
+		return 0;
+
+	_dm_event_handler_clear_dev_info(dmevh);
+
+	dmevh->dev_name = dm_strdup(dev_name);
+	if (!dmevh->dev_name)
+		return -ENOMEM;
+	return 0;
+}
+
+int dm_event_handler_set_uuid(struct dm_event_handler *dmevh, const char *uuid)
+{
+	if (!uuid)
+		return 0;
+
+	_dm_event_handler_clear_dev_info(dmevh);
+
+	dmevh->uuid = dm_strdup(uuid);
+	if (!dmevh->uuid)
+		return -ENOMEM;
+	return 0;
+}
+
+void dm_event_handler_set_major(struct dm_event_handler *dmevh, int major)
+{
+	int minor = dmevh->minor;
+
+	_dm_event_handler_clear_dev_info(dmevh);
+
+	dmevh->major = major;
+	dmevh->minor = minor;
+}
+
+void dm_event_handler_set_minor(struct dm_event_handler *dmevh, int minor)
+{
+	int major = dmevh->major;
+
+	_dm_event_handler_clear_dev_info(dmevh);
+
+	dmevh->major = major;
+	dmevh->minor = minor;
+}
+
+void dm_event_handler_set_event_mask(struct dm_event_handler *dmevh,
+				     enum dm_event_mask evmask)
+{
+	dmevh->mask = evmask;
+}
+
+void dm_event_handler_set_timeout(struct dm_event_handler *dmevh, int timeout)
+{
+	dmevh->timeout = timeout;
+}
+
+const char *dm_event_handler_get_dso(const struct dm_event_handler *dmevh)
+{
+	return dmevh->dso;
+}
+
+const char *dm_event_handler_get_dev_name(const struct dm_event_handler *dmevh)
+{
+	return dmevh->dev_name;
+}
+
+const char *dm_event_handler_get_uuid(const struct dm_event_handler *dmevh)
+{
+	return dmevh->uuid;
+}
+
+int dm_event_handler_get_major(const struct dm_event_handler *dmevh)
+{
+	return dmevh->major;
+}
+
+int dm_event_handler_get_minor(const struct dm_event_handler *dmevh)
+{
+	return dmevh->minor;
+}
+
+int dm_event_handler_get_timeout(const struct dm_event_handler *dmevh)
+{
+	return dmevh->timeout;
+}
+
+enum dm_event_mask dm_event_handler_get_event_mask(const struct dm_event_handler *dmevh)
+{
+	return dmevh->mask;
+}
+
+static int _check_message_id(struct dm_event_daemon_message *msg)
+{
+	int pid, seq_nr;
+
+	if ((sscanf(msg->data, "%d:%d", &pid, &seq_nr) != 2) ||
+	    (pid != getpid()) || (seq_nr != _sequence_nr)) {
+		log_error("Ignoring out-of-sequence reply from dmeventd. "
+			  "Expected %d:%d but received %s", getpid(),
+			  _sequence_nr, msg->data);
+		return 0;
+	}
+
+	return 1;
+}
+
+/*
+ * daemon_read
+ * @fifos
+ * @msg
+ *
+ * Read message from daemon.
+ *
+ * Returns: 0 on failure, 1 on success
+ */
+static int _daemon_read(struct dm_event_fifos *fifos,
+			struct dm_event_daemon_message *msg)
+{
+	unsigned bytes = 0;
+	int ret, i;
+	fd_set fds;
+	struct timeval tval = { 0, 0 };
+	size_t size = 2 * sizeof(uint32_t);	/* status + size */
+	uint32_t *header = alloca(size);
+	char *buf = (char *)header;
+	struct stat fstatbuf;
+
+	while (bytes < size) {
+		for (i = 0, ret = 0; (i < 20) && (ret < 1); i++) {
+			/* Watch daemon read FIFO for input. */
+			FD_ZERO(&fds);
+			FD_SET(fifos->server, &fds);
+			tval.tv_sec = 1;
+			ret = select(fifos->server + 1, &fds, NULL, NULL,
+				     &tval);
+			if (ret < 0 && errno != EINTR) {
+				log_error("Unable to read from event server");
+				return 0;
+			}
+			/* Check whether fifo is still alive */
+			if ((ret == 0) &&
+			    fstat(fifos->server + 1, &fstatbuf) &&
+			    (errno == EBADF)) {
+				log_error("Fifo fd is bad for event server.");
+				return 0;
+			}
+		}
+		if (ret < 1) {
+			log_error("Unable to read from event server.");
+			return 0;
+		}
+
+		ret = read(fifos->server, buf + bytes, size);
+		if (ret < 0) {
+			if ((errno == EINTR) || (errno == EAGAIN))
+				continue;
+			else {
+				log_error("Unable to read from event server.");
+				return 0;
+			}
+		}
+
+		bytes += ret;
+		if (header && (bytes == 2 * sizeof(uint32_t))) {
+			msg->cmd = ntohl(header[0]);
+			msg->size = ntohl(header[1]);
+			buf = msg->data = dm_malloc(msg->size);
+			size = msg->size;
+			bytes = 0;
+			header = 0;
+		}
+	}
+
+	if (bytes != size) {
+		dm_free(msg->data);
+		msg->data = NULL;
+	}
+	return bytes == size;
+}
+
+/* Write message to daemon. */
+static int _daemon_write(struct dm_event_fifos *fifos,
+			 struct dm_event_daemon_message *msg)
+{
+	unsigned bytes = 0;
+	int ret = 0;
+	fd_set fds;
+
+	size_t size = 2 * sizeof(uint32_t) + msg->size;
+	uint32_t *header = alloca(size);
+	char *buf = (char *)header;
+	char drainbuf[128];
+	struct timeval tval = { 0, 0 };
+
+	header[0] = htonl(msg->cmd);
+	header[1] = htonl(msg->size);
+	memcpy(buf + 2 * sizeof(uint32_t), msg->data, msg->size);
+
+	/* drain the answer fifo */
+	while (1) {
+		FD_ZERO(&fds);
+		FD_SET(fifos->server, &fds);
+		tval.tv_usec = 100;
+		ret = select(fifos->server + 1, &fds, NULL, NULL, &tval);
+		if ((ret < 0) && (errno != EINTR)) {
+			log_error("Unable to talk to event daemon");
+			return 0;
+		}
+		if (ret == 0)
+			break;
+		ret = read(fifos->server, drainbuf, 127);
+	}
+
+	while (bytes < size) {
+		do {
+			/* Watch daemon write FIFO to be ready for output. */
+			FD_ZERO(&fds);
+			FD_SET(fifos->client, &fds);
+			ret = select(fifos->client + 1, NULL, &fds, NULL, NULL);
+			if ((ret < 0) && (errno != EINTR)) {
+				log_error("Unable to talk to event daemon");
+				return 0;
+			}
+		} while (ret < 1);
+
+		ret = write(fifos->client, buf + bytes, size - bytes);
+		if (ret < 0) {
+			if ((errno == EINTR) || (errno == EAGAIN))
+				continue;
+			else {
+				log_error("Unable to talk to event daemon");
+				return 0;
+			}
+		}
+
+		bytes += ret;
+	}
+
+	return bytes == size;
+}
+
+int daemon_talk(struct dm_event_fifos *fifos,
+		struct dm_event_daemon_message *msg, int cmd,
+		const char *dso_name, const char *dev_name,
+		enum dm_event_mask evmask, uint32_t timeout)
+{
+	const char *dso = dso_name ? dso_name : "-";
+	const char *dev = dev_name ? dev_name : "-";
+	const char *fmt = "%d:%d %s %s %u %" PRIu32;
+	int msg_size;
+	memset(msg, 0, sizeof(*msg));
+
+	/*
+	 * Set command and pack the arguments
+	 * into ASCII message string.
+	 */
+	msg->cmd = cmd;
+	if (cmd == DM_EVENT_CMD_HELLO)
+		fmt = "%d:%d HELLO";
+	if ((msg_size = dm_asprintf(&(msg->data), fmt, getpid(), _sequence_nr,
+				    dso, dev, evmask, timeout)) < 0) {
+		log_error("_daemon_talk: message allocation failed");
+		return -ENOMEM;
+	}
+	msg->size = msg_size;
+
+	/*
+	 * Write command and message to and
+	 * read status return code from daemon.
+	 */
+	if (!_daemon_write(fifos, msg)) {
+		stack;
+		dm_free(msg->data);
+		msg->data = 0;
+		return -EIO;
+	}
+
+	do {
+
+		dm_free(msg->data);
+		msg->data = 0;
+
+		if (!_daemon_read(fifos, msg)) {
+			stack;
+			return -EIO;
+		}
+	} while (!_check_message_id(msg));
+
+	_sequence_nr++;
+
+	return (int32_t) msg->cmd;
+}
+
+/*
+ * start_daemon
+ *
+ * This function forks off a process (dmeventd) that will handle
+ * the events.  I am currently test opening one of the fifos to
+ * ensure that the daemon is running and listening...  I thought
+ * this would be less expensive than fork/exec'ing every time.
+ * Perhaps there is an even quicker/better way (no, checking the
+ * lock file is _not_ a better way).
+ *
+ * Returns: 1 on success, 0 otherwise
+ */
+static int _start_daemon(char *dmeventd_path, struct dm_event_fifos *fifos)
+{
+	int pid, ret = 0;
+	int status;
+	struct stat statbuf;
+	char default_dmeventd_path[] = DMEVENTD_PATH;
+	char *args[] = { dmeventd_path ? : default_dmeventd_path, NULL };
+
+	if (stat(fifos->client_path, &statbuf))
+		goto start_server;
+
+	if (!S_ISFIFO(statbuf.st_mode)) {
+		log_error("%s is not a fifo.", fifos->client_path);
+		return 0;
+	}
+
+	/* Anyone listening?  If not, errno will be ENXIO */
+	fifos->client = open(fifos->client_path, O_WRONLY | O_NONBLOCK);
+	if (fifos->client >= 0) {
+		/* server is running and listening */
+
+		close(fifos->client);
+		return 1;
+	} else if (errno != ENXIO) {
+		/* problem */
+
+		log_error("%s: Can't open client fifo %s: %s",
+			  __func__, fifos->client_path, strerror(errno));
+		return 0;
+	}
+
+      start_server:
+	/* server is not running */
+
+	if (!strncmp(DMEVENTD_PATH, "/", 1) && stat(DMEVENTD_PATH, &statbuf)) {
+		log_error("Unable to find dmeventd.");
+		return 0;
+	}
+
+	pid = fork();
+
+	if (pid < 0)
+		log_error("Unable to fork.");
+
+	else if (!pid) {
+		execvp(args[0], args);
+		log_error("Unable to exec dmeventd: %s", strerror(errno));
+		_exit(EXIT_FAILURE);
+	} else {
+		if (waitpid(pid, &status, 0) < 0)
+			log_error("Unable to start dmeventd: %s",
+				  strerror(errno));
+		else if (WEXITSTATUS(status))
+			log_error("Unable to start dmeventd.");
+		else
+			ret = 1;
+	}
+
+	return ret;
+}
+
+int init_fifos(struct dm_event_fifos *fifos)
+{
+	/* FIXME? Is fifo the most suitable method? Why not share
+	   comms/daemon code with something else e.g. multipath? */
+
+	/* FIXME Make these either configurable or depend directly on dmeventd_path */
+	fifos->client_path = DM_EVENT_FIFO_CLIENT;
+	fifos->server_path = DM_EVENT_FIFO_SERVER;
+
+	/* Open the fifo used to read from the daemon. */
+	if ((fifos->server = open(fifos->server_path, O_RDWR)) < 0) {
+		log_error("%s: open server fifo %s",
+			  __func__, fifos->server_path);
+		return 0;
+	}
+
+	/* Lock out anyone else trying to do communication with the daemon. */
+	if (flock(fifos->server, LOCK_EX) < 0) {
+		log_error("%s: flock %s", __func__, fifos->server_path);
+		close(fifos->server);
+		return 0;
+	}
+
+/*	if ((fifos->client = open(fifos->client_path, O_WRONLY | O_NONBLOCK)) < 0) {*/
+	if ((fifos->client = open(fifos->client_path, O_RDWR | O_NONBLOCK)) < 0) {
+		log_error("%s: Can't open client fifo %s: %s",
+			  __func__, fifos->client_path, strerror(errno));
+		close(fifos->server);
+		return 0;
+	}
+
+	return 1;
+}
+
+/* Initialize client. */
+static int _init_client(char *dmeventd_path, struct dm_event_fifos *fifos)
+{
+	/* init fifos */
+	memset(fifos, 0, sizeof(*fifos));
+
+	/* FIXME Make these either configurable or depend directly on dmeventd_path */
+	fifos->client_path = DM_EVENT_FIFO_CLIENT;
+	fifos->server_path = DM_EVENT_FIFO_SERVER;
+
+	if (!_start_daemon(dmeventd_path, fifos))
+		return_0;
+
+	return init_fifos(fifos);
+}
+
+void fini_fifos(struct dm_event_fifos *fifos)
+{
+	if (flock(fifos->server, LOCK_UN))
+		log_error("flock unlock %s", fifos->server_path);
+
+	close(fifos->client);
+	close(fifos->server);
+}
+
+/* Get uuid of a device */
+static struct dm_task *_get_device_info(const struct dm_event_handler *dmevh)
+{
+	struct dm_task *dmt;
+	struct dm_info info;
+
+	if (!(dmt = dm_task_create(DM_DEVICE_INFO))) {
+		log_error("_get_device_info: dm_task creation for info failed");
+		return NULL;
+	}
+
+	if (dmevh->uuid) {
+		if (!dm_task_set_uuid(dmt, dmevh->uuid))
+			goto_bad;
+	} else if (dmevh->dev_name) {
+		if (!dm_task_set_name(dmt, dmevh->dev_name))
+			goto_bad;
+	} else if (dmevh->major && dmevh->minor) {
+		if (!dm_task_set_major(dmt, dmevh->major) ||
+		    !dm_task_set_minor(dmt, dmevh->minor))
+			goto_bad;
+	}
+
+	/* FIXME Add name or uuid or devno to messages */
+	if (!dm_task_run(dmt)) {
+		log_error("_get_device_info: dm_task_run() failed");
+		goto bad;
+	}
+
+	if (!dm_task_get_info(dmt, &info)) {
+		log_error("_get_device_info: failed to get info for device");
+		goto bad;
+	}
+
+	if (!info.exists) {
+		log_error("_get_device_info: %s%s%s%.0d%s%.0d%s%s: device not found",
+			  dmevh->uuid ? : "", 
+			  (!dmevh->uuid && dmevh->dev_name) ? dmevh->dev_name : "", 
+			  (!dmevh->uuid && !dmevh->dev_name && dmevh->major > 0) ? "(" : "",
+			  (!dmevh->uuid && !dmevh->dev_name && dmevh->major > 0) ? dmevh->major : 0,
+			  (!dmevh->uuid && !dmevh->dev_name && dmevh->major > 0) ? ":" : "",
+			  (!dmevh->uuid && !dmevh->dev_name && dmevh->minor > 0) ? dmevh->minor : 0,
+			  (!dmevh->uuid && !dmevh->dev_name && dmevh->major > 0) && dmevh->minor == 0 ? "0" : "",
+			  (!dmevh->uuid && !dmevh->dev_name && dmevh->major > 0) ? ") " : "");
+		goto bad;
+	}
+
+		  
+	return dmt;
+
+      bad:
+	dm_task_destroy(dmt);
+	return NULL;
+}
+
+/* Handle the event (de)registration call and return negative error codes. */
+static int _do_event(int cmd, char *dmeventd_path, struct dm_event_daemon_message *msg,
+		     const char *dso_name, const char *dev_name,
+		     enum dm_event_mask evmask, uint32_t timeout)
+{
+	int ret;
+	struct dm_event_fifos fifos;
+
+	if (!_init_client(dmeventd_path, &fifos)) {
+		stack;
+		return -ESRCH;
+	}
+
+	ret = daemon_talk(&fifos, msg, DM_EVENT_CMD_HELLO, NULL, NULL, 0, 0);
+
+	dm_free(msg->data);
+	msg->data = 0;
+
+	if (!ret)
+		ret = daemon_talk(&fifos, msg, cmd, dso_name, dev_name, evmask, timeout);
+
+	/* what is the opposite of init? */
+	fini_fifos(&fifos);
+
+	return ret;
+}
+
+/* External library interface. */
+int dm_event_register_handler(const struct dm_event_handler *dmevh)
+{
+	int ret = 1, err;
+	const char *uuid;
+	struct dm_task *dmt;
+	struct dm_event_daemon_message msg = { 0, 0, NULL };
+
+	if (!(dmt = _get_device_info(dmevh))) {
+		stack;
+		return 0;
+	}
+
+	uuid = dm_task_get_uuid(dmt);
+
+	if ((err = _do_event(DM_EVENT_CMD_REGISTER_FOR_EVENT, dmevh->dmeventd_path, &msg,
+			     dmevh->dso, uuid, dmevh->mask, dmevh->timeout)) < 0) {
+		log_error("%s: event registration failed: %s",
+			  dm_task_get_name(dmt),
+			  msg.data ? msg.data : strerror(-err));
+		ret = 0;
+	}
+
+	dm_free(msg.data);
+
+	dm_task_destroy(dmt);
+
+	return ret;
+}
+
+int dm_event_unregister_handler(const struct dm_event_handler *dmevh)
+{
+	int ret = 1, err;
+	const char *uuid;
+	struct dm_task *dmt;
+	struct dm_event_daemon_message msg = { 0, 0, NULL };
+
+	if (!(dmt = _get_device_info(dmevh))) {
+		stack;
+		return 0;
+	}
+
+	uuid = dm_task_get_uuid(dmt);
+
+	if ((err = _do_event(DM_EVENT_CMD_UNREGISTER_FOR_EVENT, dmevh->dmeventd_path, &msg,
+			    dmevh->dso, uuid, dmevh->mask, dmevh->timeout)) < 0) {
+		log_error("%s: event deregistration failed: %s",
+			  dm_task_get_name(dmt),
+			  msg.data ? msg.data : strerror(-err));
+		ret = 0;
+	}
+
+	dm_free(msg.data);
+
+	dm_task_destroy(dmt);
+
+	return ret;
+}
+
+/* Fetch a string off src and duplicate it into *dest. */
+/* FIXME: move to separate module to share with the daemon. */
+static char *_fetch_string(char **src, const int delimiter)
+{
+	char *p, *ret;
+
+	if ((p = strchr(*src, delimiter)))
+		*p = 0;
+
+	if ((ret = dm_strdup(*src)))
+		*src += strlen(ret) + 1;
+
+	if (p)
+		*p = delimiter;
+
+	return ret;
+}
+
+/* Parse a device message from the daemon. */
+static int _parse_message(struct dm_event_daemon_message *msg, char **dso_name,
+			 char **uuid, enum dm_event_mask *evmask)
+{
+	char *id = NULL;
+	char *p = msg->data;
+
+	if ((id = _fetch_string(&p, ' ')) &&
+	    (*dso_name = _fetch_string(&p, ' ')) &&
+	    (*uuid = _fetch_string(&p, ' '))) {
+		*evmask = atoi(p);
+
+		dm_free(id);
+		return 0;
+	}
+
+	if (id)
+		dm_free(id);
+	return -ENOMEM;
+}
+
+/*
+ * Returns 0 if handler found; error (-ENOMEM, -ENOENT) otherwise.
+ */
+int dm_event_get_registered_device(struct dm_event_handler *dmevh, int next)
+{
+	int ret = 0;
+	const char *uuid = NULL;
+	char *reply_dso = NULL, *reply_uuid = NULL;
+	enum dm_event_mask reply_mask = 0;
+	struct dm_task *dmt = NULL;
+	struct dm_event_daemon_message msg = { 0, 0, NULL };
+	struct dm_info info;
+
+	if (!(dmt = _get_device_info(dmevh))) {
+		stack;
+		return 0;
+	}
+
+	uuid = dm_task_get_uuid(dmt);
+
+	if (_do_event(next ? DM_EVENT_CMD_GET_NEXT_REGISTERED_DEVICE :
+		      DM_EVENT_CMD_GET_REGISTERED_DEVICE, dmevh->dmeventd_path,
+		      &msg, dmevh->dso, uuid, dmevh->mask, 0)) {
+		ret = -ENOENT;
+		stack;
+		goto fail;
+	}
+
+	/* FIXME this will probably horribly break if we get
+	   ill-formatted reply */
+	ret = _parse_message(&msg, &reply_dso, &reply_uuid, &reply_mask);
+
+	dm_task_destroy(dmt);
+	dmt = NULL;
+
+	dm_free(msg.data);
+	msg.data = NULL;
+
+	_dm_event_handler_clear_dev_info(dmevh);
+	if (!reply_uuid) {
+		ret = -ENXIO; /* dmeventd probably gave us bogus uuid back */
+		goto fail;
+	}
+	dmevh->uuid = dm_strdup(reply_uuid);
+	if (!dmevh->uuid) {
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	if (!(dmt = _get_device_info(dmevh))) {
+		ret = -ENXIO; /* dmeventd probably gave us bogus uuid back */
+		goto fail;
+	}
+
+	dm_event_handler_set_dso(dmevh, reply_dso);
+	dm_event_handler_set_event_mask(dmevh, reply_mask);
+
+	dm_free(reply_dso);
+	reply_dso = NULL;
+
+	dm_free(reply_uuid);
+	reply_uuid = NULL;
+
+	dmevh->dev_name = dm_strdup(dm_task_get_name(dmt));
+	if (!dmevh->dev_name) {
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	if (!dm_task_get_info(dmt, &info)) {
+		ret = -1;
+		goto fail;
+	}
+
+	dmevh->major = info.major;
+	dmevh->minor = info.minor;
+
+	dm_task_destroy(dmt);
+
+	return ret;
+
+ fail:
+	dm_free(msg.data);
+	dm_free(reply_dso);
+	dm_free(reply_uuid);
+	_dm_event_handler_clear_dev_info(dmevh);
+	if (dmt)
+		dm_task_destroy(dmt);
+	return ret;
+}
+
+/*
+ * You can (and have to) call this at the stage of the protocol where
+ *     daemon_talk(fifos, &msg, DM_EVENT_CMD_HELLO, NULL, NULL, 0, 0)
+ *
+ * would be normally sent. This call will parse the version reply from
+ * dmeventd, in addition to above call. It is not safe to call this at any
+ * other place in the protocol.
+ *
+ * This is an internal function, not exposed in the public API.
+ */
+
+int dm_event_get_version(struct dm_event_fifos *fifos, int *version) {
+	char *p;
+	struct dm_event_daemon_message msg = { 0, 0, NULL };
+
+	if (daemon_talk(fifos, &msg, DM_EVENT_CMD_HELLO, NULL, NULL, 0, 0))
+		return 0;
+	p = msg.data;
+	*version = 0;
+
+	p = strchr(p, ' '); /* Message ID */
+        if (!p) return 0;
+	p = strchr(p + 1, ' '); /* HELLO */
+        if (!p) return 0;
+	p = strchr(p + 1, ' '); /* HELLO, once more */
+	if (p)
+		*version = atoi(p);
+	return 1;
+}
+
+#if 0				/* left out for now */
+
+static char *_skip_string(char *src, const int delimiter)
+{
+	src = srtchr(src, delimiter);
+	if (src && *(src + 1))
+		return src + 1;
+	return NULL;
+}
+
+int dm_event_set_timeout(const char *device_path, uint32_t timeout)
+{
+	struct dm_event_daemon_message msg = { 0, 0, NULL };
+
+	if (!device_exists(device_path))
+		return -ENODEV;
+
+	return _do_event(DM_EVENT_CMD_SET_TIMEOUT, &msg,
+			 NULL, device_path, 0, timeout);
+}
+
+int dm_event_get_timeout(const char *device_path, uint32_t *timeout)
+{
+	int ret;
+	struct dm_event_daemon_message msg = { 0, 0, NULL };
+
+	if (!device_exists(device_path))
+		return -ENODEV;
+	if (!(ret = _do_event(DM_EVENT_CMD_GET_TIMEOUT, &msg, NULL, device_path,
+			     0, 0))) {
+		char *p = _skip_string(msg.data, ' ');
+		if (!p) {
+			log_error("malformed reply from dmeventd '%s'\n",
+				  msg.data);
+			return -EIO;
+		}
+		*timeout = atoi(p);
+	}
+	if (msg.data)
+		dm_free(msg.data);
+	return ret;
+}
+#endif

daemons/dmeventd/libdevmapper-event.h

@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2005-2007 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of the device-mapper userspace tools.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/*
+ * Note that this file is released only as part of a technology preview
+ * and its contents may change in future updates in ways that do not
+ * preserve compatibility.
+ */
+
+#ifndef LIB_DMEVENT_H
+#define LIB_DMEVENT_H
+
+#include <stdint.h>
+
+/*
+ * Event library interface.
+ */
+
+enum dm_event_mask {
+	DM_EVENT_SETTINGS_MASK  = 0x0000FF,
+	DM_EVENT_SINGLE		= 0x000001, /* Report multiple errors just once. */
+	DM_EVENT_MULTI		= 0x000002, /* Report all of them. */
+
+	DM_EVENT_ERROR_MASK     = 0x00FF00,
+	DM_EVENT_SECTOR_ERROR	= 0x000100, /* Failure on a particular sector. */
+	DM_EVENT_DEVICE_ERROR	= 0x000200, /* Device failure. */
+	DM_EVENT_PATH_ERROR	= 0x000400, /* Failure on an io path. */
+	DM_EVENT_ADAPTOR_ERROR	= 0x000800, /* Failure of a host adaptor. */
+
+	DM_EVENT_STATUS_MASK    = 0xFF0000,
+	DM_EVENT_SYNC_STATUS	= 0x010000, /* Mirror synchronization completed/failed. */
+	DM_EVENT_TIMEOUT	= 0x020000, /* Timeout has occured */
+
+	DM_EVENT_REGISTRATION_PENDING = 0x1000000, /* Monitor thread is setting-up/shutting-down */
+};
+
+#define DM_EVENT_ALL_ERRORS DM_EVENT_ERROR_MASK
+#define DM_EVENT_PROTOCOL_VERSION 1
+
+struct dm_event_handler;
+
+struct dm_event_handler *dm_event_handler_create(void);
+void dm_event_handler_destroy(struct dm_event_handler *dmevh);
+
+/*
+ * Path of shared library to handle events.
+ *
+ * All of dmeventd, dso, device_name and uuid strings are duplicated so
+ * you do not need to keep the pointers valid after the call succeeds.
+ * They may return -ENOMEM though.
+ */
+int dm_event_handler_set_dso(struct dm_event_handler *dmevh, const char *path);
+
+/*
+ * Path of dmeventd binary.
+ */
+int dm_event_handler_set_dmeventd_path(struct dm_event_handler *dmevh, const char *dmeventd_path);
+
+/*
+ * Identify the device to monitor by exactly one of device_name, uuid or
+ * device number. String arguments are duplicated, see above.
+ */
+int dm_event_handler_set_dev_name(struct dm_event_handler *dmevh, const char *device_name);
+
+int dm_event_handler_set_uuid(struct dm_event_handler *dmevh, const char *uuid);
+
+void dm_event_handler_set_major(struct dm_event_handler *dmevh, int major);
+void dm_event_handler_set_minor(struct dm_event_handler *dmevh, int minor);
+void dm_event_handler_set_timeout(struct dm_event_handler *dmevh, int timeout);
+
+/*
+ * Specify mask for events to monitor.
+ */
+void dm_event_handler_set_event_mask(struct dm_event_handler *dmevh,
+				     enum dm_event_mask evmask);
+
+const char *dm_event_handler_get_dso(const struct dm_event_handler *dmevh);
+const char *dm_event_handler_get_dev_name(const struct dm_event_handler *dmevh);
+const char *dm_event_handler_get_uuid(const struct dm_event_handler *dmevh);
+int dm_event_handler_get_major(const struct dm_event_handler *dmevh);
+int dm_event_handler_get_minor(const struct dm_event_handler *dmevh);
+int dm_event_handler_get_timeout(const struct dm_event_handler *dmevh);
+enum dm_event_mask dm_event_handler_get_event_mask(const struct dm_event_handler *dmevh);
+
+/* FIXME Review interface (what about this next thing?) */
+int dm_event_get_registered_device(struct dm_event_handler *dmevh, int next);
+
+/*
+ * Initiate monitoring using dmeventd.
+ */
+int dm_event_register_handler(const struct dm_event_handler *dmevh);
+int dm_event_unregister_handler(const struct dm_event_handler *dmevh);
+
+/* Prototypes for DSO interface, see dmeventd.c, struct dso_data for
+   detailed descriptions. */
+void process_event(struct dm_task *dmt, enum dm_event_mask evmask, void **user);
+int register_device(const char *device_name, const char *uuid, int major, int minor, void **user);
+int unregister_device(const char *device_name, const char *uuid, int major,
+		      int minor, void **user);
+
+#endif

daemons/dmeventd/libdevmapper-event.pc.in

@@ -0,0 +1,11 @@
+prefix=@prefix@
+exec_prefix=@exec_prefix@
+libdir=@libdir@
+includedir=@includedir@
+
+Name: devmapper-event
+Description: device-mapper event library
+Version: @DM_LIB_PATCHLEVEL@
+Cflags: -I${includedir}
+Libs: -L${libdir} -ldevmapper-event
+Requires.private: devmapper

daemons/dmeventd/plugins/Makefile.in

@@ -0,0 +1,46 @@
+#
+# Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
+# Copyright (C) 2004-2005, 2011 Red Hat, Inc. All rights reserved.
+#
+# This file is part of LVM2.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU General Public License v.2.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+SUBDIRS += lvm2
+
+ifneq ("@MIRRORS@", "none")
+  SUBDIRS += mirror
+endif
+
+ifneq ("@SNAPSHOTS@", "none")
+  SUBDIRS += snapshot
+endif
+
+ifneq ("@RAID@", "none")
+  SUBDIRS += raid
+endif
+
+ifneq ("@THIN@", "none")
+  SUBDIRS += thin
+endif
+
+ifeq ($(MAKECMDGOALS),distclean)
+  SUBDIRS = lvm2 mirror snapshot raid thin
+endif
+
+include $(top_builddir)/make.tmpl
+
+snapshot: lvm2
+mirror: lvm2
+raid: lvm2
+thin: lvm2

daemons/dmeventd/plugins/lvm2/.exported_symbols

@@ -0,0 +1,7 @@
+dmeventd_lvm2_init
+dmeventd_lvm2_exit
+dmeventd_lvm2_lock
+dmeventd_lvm2_unlock
+dmeventd_lvm2_pool
+dmeventd_lvm2_run
+dmeventd_lvm2_command

daemons/dmeventd/plugins/lvm2/Makefile.in

@@ -0,0 +1,31 @@
+#
+# Copyright (C) 2010-2011 Red Hat, Inc. All rights reserved.
+#
+# This file is part of LVM2.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU General Public License v.2.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+CLDFLAGS += -L$(top_builddir)/tools
+
+SOURCES = dmeventd_lvm.c
+
+LIB_SHARED = libdevmapper-event-lvm2.$(LIB_SUFFIX)
+LIB_VERSION = $(LIB_VERSION_LVM)
+
+include $(top_builddir)/make.tmpl
+
+LIBS += @LVM2CMD_LIB@ -ldevmapper $(PTHREAD_LIBS)
+
+install_lvm2: install_lib_shared
+
+install: install_lvm2

daemons/dmeventd/plugins/lvm2/dmeventd_lvm.c

@@ -0,0 +1,173 @@
+/*
+ * Copyright (C) 2010 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "lib.h"
+#include "log.h"
+
+#include "lvm2cmd.h"
+#include "errors.h"
+#include "libdevmapper-event.h"
+#include "dmeventd_lvm.h"
+
+#include <pthread.h>
+#include <syslog.h>
+
+extern int dmeventd_debug;
+
+/*
+ * register_device() is called first and performs initialisation.
+ * Only one device may be registered or unregistered at a time.
+ */
+static pthread_mutex_t _register_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+/*
+ * Number of active registrations.
+ */
+static int _register_count = 0;
+static struct dm_pool *_mem_pool = NULL;
+static void *_lvm_handle = NULL;
+
+/*
+ * Currently only one event can be processed at a time.
+ */
+static pthread_mutex_t _event_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+/*
+ * FIXME Do not pass things directly to syslog, rather use the existing logging
+ * facilities to sort logging ... however that mechanism needs to be somehow
+ * configurable and we don't have that option yet
+ */
+static void _temporary_log_fn(int level,
+			      const char *file __attribute__((unused)),
+			      int line __attribute__((unused)),
+			      int dm_errno __attribute__((unused)),
+			      const char *message)
+{
+	level &= ~(_LOG_STDERR | _LOG_ONCE);
+
+	switch (level) {
+	case _LOG_DEBUG:
+		if (dmeventd_debug >= 3)
+			syslog(LOG_DEBUG, "%s", message);
+		break;
+	case _LOG_INFO:
+		if (dmeventd_debug >= 2)
+			syslog(LOG_INFO, "%s", message);
+		break;
+	case _LOG_NOTICE:
+		if (dmeventd_debug >= 1)
+			syslog(LOG_NOTICE, "%s", message);
+		break;
+	case _LOG_WARN:
+		syslog(LOG_WARNING, "%s", message);
+		break;
+	case _LOG_ERR:
+		syslog(LOG_ERR, "%s", message);
+		break;
+	default:
+		syslog(LOG_CRIT, "%s", message);
+	}
+}
+
+void dmeventd_lvm2_lock(void)
+{
+	pthread_mutex_lock(&_event_mutex);
+}
+
+void dmeventd_lvm2_unlock(void)
+{
+	pthread_mutex_unlock(&_event_mutex);
+}
+
+int dmeventd_lvm2_init(void)
+{
+	int r = 0;
+
+	pthread_mutex_lock(&_register_mutex);
+
+	/*
+	 * Need some space for allocations.  1024 should be more
+	 * than enough for what we need (device mapper name splitting)
+	 */
+	if (!_mem_pool && !(_mem_pool = dm_pool_create("mirror_dso", 1024)))
+		goto out;
+
+	if (!_lvm_handle) {
+		lvm2_log_fn(_temporary_log_fn);
+		if (!(_lvm_handle = lvm2_init())) {
+			dm_pool_destroy(_mem_pool);
+			_mem_pool = NULL;
+			goto out;
+		}
+		lvm2_disable_dmeventd_monitoring(_lvm_handle);
+		/* FIXME Temporary: move to dmeventd core */
+		lvm2_run(_lvm_handle, "_memlock_inc");
+	}
+
+	_register_count++;
+	r = 1;
+
+out:
+	pthread_mutex_unlock(&_register_mutex);
+	return r;
+}
+
+void dmeventd_lvm2_exit(void)
+{
+	pthread_mutex_lock(&_register_mutex);
+
+	if (!--_register_count) {
+		lvm2_run(_lvm_handle, "_memlock_dec");
+		dm_pool_destroy(_mem_pool);
+		_mem_pool = NULL;
+		lvm2_exit(_lvm_handle);
+		_lvm_handle = NULL;
+	}
+
+	pthread_mutex_unlock(&_register_mutex);
+}
+
+struct dm_pool *dmeventd_lvm2_pool(void)
+{
+	return _mem_pool;
+}
+
+int dmeventd_lvm2_run(const char *cmdline)
+{
+	return lvm2_run(_lvm_handle, cmdline);
+}
+
+int dmeventd_lvm2_command(struct dm_pool *mem, char *buffer, size_t size,
+			  const char *cmd, const char *device)
+{
+	char *vg = NULL, *lv = NULL, *layer;
+	int r;
+
+	if (!dm_split_lvm_name(mem, device, &vg, &lv, &layer)) {
+		syslog(LOG_ERR, "Unable to determine VG name from %s.\n",
+		       device);
+		return 0;
+	}
+
+	r = dm_snprintf(buffer, size, "%s %s/%s", cmd, vg, lv);
+
+	dm_pool_free(mem, vg);
+
+	if (r < 0) {
+		syslog(LOG_ERR, "Unable to form LVM command. (too long).\n");
+		return 0;
+	}
+
+	return 1;
+}

daemons/dmeventd/plugins/lvm2/dmeventd_lvm.h

@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2010 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/*
+ * Wrappers around liblvm2cmd functions for dmeventd plug-ins.
+ *
+ * liblvm2cmd is not thread-safe so the locking in this library helps dmeventd
+ * threads to co-operate in sharing a single instance.
+ *
+ * FIXME Either support this properly as a generic liblvm2cmd wrapper or make
+ * liblvm2cmd thread-safe so this can go away.
+ */
+
+#include "libdevmapper.h"
+
+#ifndef _DMEVENTD_LVMWRAP_H
+#define _DMEVENTD_LVMWRAP_H
+
+int dmeventd_lvm2_init(void);
+void dmeventd_lvm2_exit(void);
+int dmeventd_lvm2_run(const char *cmdline);
+
+void dmeventd_lvm2_lock(void);
+void dmeventd_lvm2_unlock(void);
+
+struct dm_pool *dmeventd_lvm2_pool(void);
+
+int dmeventd_lvm2_command(struct dm_pool *mem, char *buffer, size_t size,
+			  const char *cmd, const char *device);
+
+#endif /* _DMEVENTD_LVMWRAP_H */

daemons/dmeventd/plugins/mirror/.exported_symbols

@@ -0,0 +1,3 @@
+process_event
+register_device
+unregister_device

daemons/dmeventd/plugins/mirror/Makefile.in

@@ -0,0 +1,37 @@
+#
+# Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
+# Copyright (C) 2004-2005, 2008-2011 Red Hat, Inc. All rights reserved.
+#
+# This file is part of LVM2.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU General Public License v.2.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+INCLUDES += -I$(top_srcdir)/tools -I$(top_srcdir)/daemons/dmeventd/plugins/lvm2
+CLDFLAGS += -L$(top_builddir)/tools -L$(top_builddir)/daemons/dmeventd/plugins/lvm2
+
+SOURCES = dmeventd_mirror.c
+
+LIB_NAME = libdevmapper-event-lvm2mirror
+LIB_SHARED = $(LIB_NAME).$(LIB_SUFFIX)
+LIB_VERSION = $(LIB_VERSION_LVM)
+
+CFLOW_LIST = $(SOURCES)
+CFLOW_LIST_TARGET = $(LIB_NAME).cflow
+
+include $(top_builddir)/make.tmpl
+
+LIBS += -ldevmapper-event-lvm2 -ldevmapper
+
+install_lvm2: install_dm_plugin
+
+install: install_lvm2

daemons/dmeventd/plugins/mirror/dmeventd_mirror.c

@@ -0,0 +1,235 @@
+/*
+ * Copyright (C) 2005-2012 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "lib.h"
+
+#include "lvm2cmd.h"
+#include "errors.h"
+#include "libdevmapper-event.h"
+#include "dmeventd_lvm.h"
+#include "defaults.h"
+
+#include <syslog.h> /* FIXME Replace syslog with multilog */
+/* FIXME Missing openlog? */
+/* FIXME Replace most syslogs with log_error() style messages and add complete context. */
+/* FIXME Reformat to 80 char lines. */
+
+#define ME_IGNORE    0
+#define ME_INSYNC    1
+#define ME_FAILURE   2
+
+static int _process_status_code(const char status_code, const char *dev_name,
+				const char *dev_type, int r)
+{
+	/*
+	 *    A => Alive - No failures
+	 *    D => Dead - A write failure occurred leaving mirror out-of-sync
+	 *    F => Flush failed.
+	 *    S => Sync - A sychronization failure occurred, mirror out-of-sync
+	 *    R => Read - A read failure occurred, mirror data unaffected
+	 *    U => Unclassified failure (bug)
+	 */ 
+	if (status_code == 'F') {
+		syslog(LOG_ERR, "%s device %s flush failed.",
+		       dev_type, dev_name);
+		r = ME_FAILURE;
+	} else if (status_code == 'S')
+		syslog(LOG_ERR, "%s device %s sync failed.",
+		       dev_type, dev_name);
+	else if (status_code == 'R')
+		syslog(LOG_ERR, "%s device %s read failed.",
+		       dev_type, dev_name);
+	else if (status_code != 'A') {
+		syslog(LOG_ERR, "%s device %s has failed (%c).",
+		       dev_type, dev_name, status_code);
+		r = ME_FAILURE;
+	}
+
+	return r;
+}
+
+static int _get_mirror_event(char *params)
+{
+	int i, r = ME_INSYNC;
+	char **args = NULL;
+	char *dev_status_str;
+	char *log_status_str;
+	char *sync_str;
+	char *p = NULL;
+	int log_argc, num_devs;
+
+	/*
+	 * dm core parms:	     0 409600 mirror
+	 * Mirror core parms:	     2 253:4 253:5 400/400
+	 * New-style failure params: 1 AA
+	 * New-style log params:     3 cluster 253:3 A
+	 *			 or  3 disk 253:3 A
+	 *			 or  1 core
+	 */
+
+	/* number of devices */
+	if (!dm_split_words(params, 1, 0, &p))
+		goto out_parse;
+
+	if (!(num_devs = atoi(p)) ||
+	    (num_devs > DEFAULT_MIRROR_MAX_IMAGES) || (num_devs < 0))
+		goto out_parse;
+	p += strlen(p) + 1;
+
+	/* devices names + "400/400" + "1 AA" + 1 or 3 log parms + NULL */
+	args = dm_malloc((num_devs + 7) * sizeof(char *));
+	if (!args || dm_split_words(p, num_devs + 7, 0, args) < num_devs + 5)
+		goto out_parse;
+
+	/* FIXME: Code differs from lib/mirror/mirrored.c */
+	dev_status_str = args[2 + num_devs];
+	log_argc = atoi(args[3 + num_devs]);
+	log_status_str = args[3 + num_devs + log_argc];
+	sync_str = args[num_devs];
+
+	/* Check for bad mirror devices */
+	for (i = 0; i < num_devs; i++)
+		r = _process_status_code(dev_status_str[i], args[i],
+			i ? "Secondary mirror" : "Primary mirror", r);
+
+	/* Check for bad disk log device */
+	if (log_argc > 1)
+		r = _process_status_code(log_status_str[0],
+					 args[2 + num_devs + log_argc],
+					 "Log", r);
+
+	if (r == ME_FAILURE)
+		goto out;
+
+	p = strstr(sync_str, "/");
+	if (p) {
+		p[0] = '\0';
+		if (strcmp(sync_str, p+1))
+			r = ME_IGNORE;
+		p[0] = '/';
+	} else
+		goto out_parse;
+
+out:
+	dm_free(args);
+	return r;
+	
+out_parse:
+	dm_free(args);
+	syslog(LOG_ERR, "Unable to parse mirror status string.");
+	return ME_IGNORE;
+}
+
+static int _remove_failed_devices(const char *device)
+{
+	int r;
+#define CMD_SIZE 256	/* FIXME Use system restriction */
+	char cmd_str[CMD_SIZE];
+
+	if (!dmeventd_lvm2_command(dmeventd_lvm2_pool(), cmd_str, sizeof(cmd_str),
+				  "lvconvert --config devices{ignore_suspended_devices=1} "
+				  "--repair --use-policies", device))
+		return -ENAMETOOLONG; /* FIXME Replace with generic error return - reason for failure has already got logged */
+
+	r = dmeventd_lvm2_run(cmd_str);
+
+	syslog(LOG_INFO, "Repair of mirrored device %s %s.", device,
+	       (r == ECMD_PROCESSED) ? "finished successfully" : "failed");
+
+	return (r == ECMD_PROCESSED) ? 0 : -1;
+}
+
+void process_event(struct dm_task *dmt,
+		   enum dm_event_mask event __attribute__((unused)),
+		   void **unused __attribute__((unused)))
+{
+	void *next = NULL;
+	uint64_t start, length;
+	char *target_type = NULL;
+	char *params;
+	const char *device = dm_task_get_name(dmt);
+
+	dmeventd_lvm2_lock();
+
+	do {
+		next = dm_get_next_target(dmt, next, &start, &length,
+					  &target_type, &params);
+
+		if (!target_type) {
+			syslog(LOG_INFO, "%s mapping lost.", device);
+			continue;
+		}
+
+		if (strcmp(target_type, "mirror")) {
+			syslog(LOG_INFO, "%s has unmirrored portion.", device);
+			continue;
+		}
+
+		switch(_get_mirror_event(params)) {
+		case ME_INSYNC:
+			/* FIXME: all we really know is that this
+			   _part_ of the device is in sync
+			   Also, this is not an error
+			*/
+			syslog(LOG_NOTICE, "%s is now in-sync.", device);
+			break;
+		case ME_FAILURE:
+			syslog(LOG_ERR, "Device failure in %s.", device);
+			if (_remove_failed_devices(device))
+				/* FIXME Why are all the error return codes unused? Get rid of them? */
+				syslog(LOG_ERR, "Failed to remove faulty devices in %s.",
+				       device);
+			/* Should check before warning user that device is now linear
+			else
+				syslog(LOG_NOTICE, "%s is now a linear device.\n",
+					device);
+			*/
+			break;
+		case ME_IGNORE:
+			break;
+		default:
+			/* FIXME Provide value then! */
+			syslog(LOG_INFO, "Unknown event received.");
+		}
+	} while (next);
+
+	dmeventd_lvm2_unlock();
+}
+
+int register_device(const char *device,
+		    const char *uuid __attribute__((unused)),
+		    int major __attribute__((unused)),
+		    int minor __attribute__((unused)),
+		    void **unused __attribute__((unused)))
+{
+	if (!dmeventd_lvm2_init())
+		return 0;
+
+	syslog(LOG_INFO, "Monitoring mirror device %s for events.", device);
+
+	return 1;
+}
+
+int unregister_device(const char *device,
+		      const char *uuid __attribute__((unused)),
+		      int major __attribute__((unused)),
+		      int minor __attribute__((unused)),
+		      void **unused __attribute__((unused)))
+{
+	syslog(LOG_INFO, "No longer monitoring mirror device %s for events.",
+	       device);
+	dmeventd_lvm2_exit();
+
+	return 1;
+}

daemons/dmeventd/plugins/raid/.exported_symbols

@@ -0,0 +1,3 @@
+process_event
+register_device
+unregister_device

daemons/dmeventd/plugins/raid/Makefile.in

@@ -0,0 +1,36 @@
+#
+# Copyright (C) 2011 Red Hat, Inc. All rights reserved.
+#
+# This file is part of LVM2.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU General Public License v.2.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+INCLUDES += -I$(top_srcdir)/tools -I$(top_srcdir)/daemons/dmeventd/plugins/lvm2
+CLDFLAGS += -L$(top_builddir)/tools -L$(top_builddir)/daemons/dmeventd/plugins/lvm2
+
+SOURCES = dmeventd_raid.c
+
+LIB_NAME = libdevmapper-event-lvm2raid
+LIB_SHARED = $(LIB_NAME).$(LIB_SUFFIX)
+LIB_VERSION = $(LIB_VERSION_LVM)
+
+CFLOW_LIST = $(SOURCES)
+CFLOW_LIST_TARGET = $(LIB_NAME).cflow
+
+include $(top_builddir)/make.tmpl
+
+LIBS += -ldevmapper-event-lvm2 -ldevmapper
+
+install_lvm2: install_dm_plugin
+
+install: install_lvm2

daemons/dmeventd/plugins/raid/dmeventd_raid.c

@@ -0,0 +1,172 @@
+/*
+ * Copyright (C) 2005-2011 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "lib.h"
+
+#include "lvm2cmd.h"
+#include "errors.h"
+#include "libdevmapper-event.h"
+#include "dmeventd_lvm.h"
+
+#include <syslog.h> /* FIXME Replace syslog with multilog */
+/* FIXME Missing openlog? */
+/* FIXME Replace most syslogs with log_error() style messages and add complete context. */
+/* FIXME Reformat to 80 char lines. */
+
+/*
+ * run_repair is a close copy to
+ * plugins/mirror/dmeventd_mirror.c:_remove_failed_devices()
+ */
+static int run_repair(const char *device)
+{
+	int r;
+#define CMD_SIZE 256	/* FIXME Use system restriction */
+	char cmd_str[CMD_SIZE];
+
+	if (!dmeventd_lvm2_command(dmeventd_lvm2_pool(), cmd_str, sizeof(cmd_str),
+				  "lvconvert --config devices{ignore_suspended_devices=1} "
+				  "--repair --use-policies", device))
+		return -1;
+
+	r = dmeventd_lvm2_run(cmd_str);
+
+	if (r != ECMD_PROCESSED)
+		syslog(LOG_INFO, "Repair of RAID device %s failed.", device);
+
+	return (r == ECMD_PROCESSED) ? 0 : -1;
+}
+
+static int _process_raid_event(char *params, const char *device)
+{
+	int i, n, failure = 0;
+	char *p, *a[4];
+	char *raid_type;
+	char *num_devices;
+	char *health_chars;
+	char *resync_ratio;
+
+	/*
+	 * RAID parms:     <raid_type> <#raid_disks> \
+	 *                 <health chars> <resync ratio>
+	 */
+	if (!dm_split_words(params, 4, 0, a)) {
+		syslog(LOG_ERR, "Failed to process status line for %s\n",
+		       device);
+		return -EINVAL;
+	}
+	raid_type = a[0];
+	num_devices = a[1];
+	health_chars = a[2];
+	resync_ratio = a[3];
+
+	if (!(n = atoi(num_devices))) {
+		syslog(LOG_ERR, "Failed to parse number of devices for %s: %s",
+		       device, num_devices);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < n; i++) {
+		switch (health_chars[i]) {
+		case 'A':
+			/* Device is 'A'live and well */
+		case 'a':
+			/* Device is 'a'live, but not yet in-sync */
+			break;
+		case 'D':
+			syslog(LOG_ERR,
+			       "Device #%d of %s array, %s, has failed.",
+			       i, raid_type, device);
+			failure++;
+			break;
+		default:
+			/* Unhandled character returned from kernel */
+			break;
+		}
+		if (failure)
+			return run_repair(device);
+	}
+
+	p = strstr(resync_ratio, "/");
+	if (!p) {
+		syslog(LOG_ERR, "Failed to parse resync_ratio for %s: %s",
+		       device, resync_ratio);
+		return -EINVAL;
+	}
+	p[0] = '\0';
+	syslog(LOG_INFO, "%s array, %s, is %s in-sync.",
+	       raid_type, device, strcmp(resync_ratio, p+1) ? "not" : "now");
+
+	return 0;
+}
+
+void process_event(struct dm_task *dmt,
+		   enum dm_event_mask event __attribute__((unused)),
+		   void **unused __attribute__((unused)))
+{
+	void *next = NULL;
+	uint64_t start, length;
+	char *target_type = NULL;
+	char *params;
+	const char *device = dm_task_get_name(dmt);
+
+	dmeventd_lvm2_lock();
+
+	do {
+		next = dm_get_next_target(dmt, next, &start, &length,
+					  &target_type, &params);
+
+		if (!target_type) {
+			syslog(LOG_INFO, "%s mapping lost.", device);
+			continue;
+		}
+
+		if (strcmp(target_type, "raid")) {
+			syslog(LOG_INFO, "%s has non-raid portion.", device);
+			continue;
+		}
+
+		if (_process_raid_event(params, device))
+			syslog(LOG_ERR, "Failed to process event for %s",
+			       device);
+	} while (next);
+
+	dmeventd_lvm2_unlock();
+}
+
+int register_device(const char *device,
+		    const char *uuid __attribute__((unused)),
+		    int major __attribute__((unused)),
+		    int minor __attribute__((unused)),
+		    void **unused __attribute__((unused)))
+{
+	if (!dmeventd_lvm2_init())
+		return 0;
+
+	syslog(LOG_INFO, "Monitoring RAID device %s for events.", device);
+
+	return 1;
+}
+
+int unregister_device(const char *device,
+		      const char *uuid __attribute__((unused)),
+		      int major __attribute__((unused)),
+		      int minor __attribute__((unused)),
+		      void **unused __attribute__((unused)))
+{
+	syslog(LOG_INFO, "No longer monitoring RAID device %s for events.",
+	       device);
+	dmeventd_lvm2_exit();
+
+	return 1;
+}

daemons/dmeventd/plugins/snapshot/.exported_symbols

@@ -0,0 +1,3 @@
+process_event
+register_device
+unregister_device

daemons/dmeventd/plugins/snapshot/Makefile.in

@@ -0,0 +1,33 @@
+#
+# Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
+# Copyright (C) 2004-2011 Red Hat, Inc. All rights reserved.
+#
+# This file is part of the LVM2.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU General Public License v.2.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+INCLUDES += -I$(top_srcdir)/tools -I$(top_srcdir)/daemons/dmeventd/plugins/lvm2
+CLDFLAGS += -L$(top_builddir)/tools -L$(top_builddir)/daemons/dmeventd/plugins/lvm2
+
+SOURCES = dmeventd_snapshot.c
+
+LIB_SHARED = libdevmapper-event-lvm2snapshot.$(LIB_SUFFIX)
+LIB_VERSION = $(LIB_VERSION_LVM)
+
+include $(top_builddir)/make.tmpl
+
+LIBS += -ldevmapper-event-lvm2 -ldevmapper
+
+install_lvm2: install_dm_plugin
+
+install: install_lvm2

daemons/dmeventd/plugins/snapshot/dmeventd_snapshot.c

@@ -0,0 +1,283 @@
+/*
+ * Copyright (C) 2007-2011 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "lib.h"
+
+#include "lvm2cmd.h"
+#include "errors.h"
+#include "libdevmapper-event.h"
+#include "dmeventd_lvm.h"
+
+#include "lvm-string.h"
+
+#include <sys/wait.h>
+#include <syslog.h> /* FIXME Replace syslog with multilog */
+/* FIXME Missing openlog? */
+
+/* First warning when snapshot is 80% full. */
+#define WARNING_THRESH 80
+/* Run a check every 5%. */
+#define CHECK_STEP 5
+/* Do not bother checking snapshots less than 50% full. */
+#define CHECK_MINIMUM 50
+
+#define UMOUNT_COMMAND "/bin/umount"
+
+struct snap_status {
+	int invalid;
+	int used;
+	int max;
+};
+
+struct dso_state {
+	int percent_check;
+	int known_size;
+	char cmd_str[1024];
+};
+
+/* FIXME possibly reconcile this with target_percent when we gain
+   access to regular LVM library here. */
+static void _parse_snapshot_params(char *params, struct snap_status *status)
+{
+	char *p;
+	/*
+	 * xx/xx	-- fractions used/max
+	 * Invalid	-- snapshot invalidated
+	 * Unknown	-- status unknown
+	 */
+	status->used = status->max = 0;
+
+	if (!strncmp(params, "Invalid", 7)) {
+		status->invalid = 1;
+		return;
+	}
+
+	/*
+	 * When we return without setting non-zero max, the parent is
+	 * responsible for reporting errors.
+	 */
+	if (!strncmp(params, "Unknown", 7))
+		return;
+
+	if (!(p = strstr(params, "/")))
+		return;
+
+	*p = '\0';
+	p++;
+
+	status->used = atoi(params);
+	status->max = atoi(p);
+}
+
+static int _run(const char *cmd, ...)
+{
+        va_list ap;
+        int argc = 1; /* for argv[0], i.e. cmd */
+        int i = 0;
+        const char **argv;
+        pid_t pid = fork();
+        int status;
+
+        if (pid == 0) { /* child */
+                va_start(ap, cmd);
+                while (va_arg(ap, const char *))
+                        ++ argc;
+                va_end(ap);
+
+                /* + 1 for the terminating NULL */
+                argv = alloca(sizeof(const char *) * (argc + 1));
+
+                argv[0] = cmd;
+                va_start(ap, cmd);
+                while ((argv[++i] = va_arg(ap, const char *)));
+                va_end(ap);
+
+                execvp(cmd, (char **)argv);
+                syslog(LOG_ERR, "Failed to execute %s: %s.\n", cmd, strerror(errno));
+                exit(127);
+        }
+
+        if (pid > 0) { /* parent */
+                if (waitpid(pid, &status, 0) != pid)
+                        return 0; /* waitpid failed */
+                if (!WIFEXITED(status) || WEXITSTATUS(status))
+                        return 0; /* the child failed */
+        }
+
+        if (pid < 0)
+                return 0; /* fork failed */
+
+        return 1; /* all good */
+}
+
+static int _extend(const char *cmd)
+{
+	return dmeventd_lvm2_run(cmd) == ECMD_PROCESSED;
+}
+
+static void _umount(const char *device, int major, int minor)
+{
+	FILE *mounts;
+	char buffer[4096];
+	char *words[3];
+	struct stat st;
+
+	if (!(mounts = fopen("/proc/mounts", "r"))) {
+		syslog(LOG_ERR, "Could not read /proc/mounts. Not umounting %s.\n", device);
+		return;
+	}
+
+	while (!feof(mounts)) {
+		/* read a line of /proc/mounts */
+		if (!fgets(buffer, sizeof(buffer), mounts))
+			break; /* eof, likely */
+
+		/* words[0] is the mount point and words[1] is the device path */
+		if (dm_split_words(buffer, 3, 0, words) < 2)
+			continue;
+
+		/* find the major/minor of the device */
+		if (stat(words[0], &st))
+			continue; /* can't stat, skip this one */
+
+		if (S_ISBLK(st.st_mode) &&
+		    major(st.st_rdev) == major &&
+		    minor(st.st_rdev) == minor) {
+			syslog(LOG_ERR, "Unmounting invalid snapshot %s from %s.\n", device, words[1]);
+                        if (!_run(UMOUNT_COMMAND, "-fl", words[1], NULL))
+                                syslog(LOG_ERR, "Failed to umount snapshot %s from %s: %s.\n",
+                                       device, words[1], strerror(errno));
+		}
+	}
+
+	if (fclose(mounts))
+		syslog(LOG_ERR, "Failed to close /proc/mounts.\n");
+}
+
+void process_event(struct dm_task *dmt,
+		   enum dm_event_mask event __attribute__((unused)),
+		   void **private)
+{
+	void *next = NULL;
+	uint64_t start, length;
+	char *target_type = NULL;
+	char *params;
+	struct snap_status status = { 0 };
+	const char *device = dm_task_get_name(dmt);
+	int percent;
+	struct dso_state *state = *private;
+
+	/* No longer monitoring, waiting for remove */
+	if (!state->percent_check)
+		return;
+
+	dmeventd_lvm2_lock();
+
+	dm_get_next_target(dmt, next, &start, &length, &target_type, &params);
+	if (!target_type)
+		goto out;
+
+	_parse_snapshot_params(params, &status);
+
+	if (status.invalid) {
+		struct dm_info info;
+		if (dm_task_get_info(dmt, &info)) {
+			dmeventd_lvm2_unlock();
+			_umount(device, info.major, info.minor);
+                        return;
+		} /* else; too bad, but this is best-effort thing... */
+	}
+
+	/* Snapshot size had changed. Clear the threshold. */
+	if (state->known_size != status.max) {
+		state->percent_check = CHECK_MINIMUM;
+		state->known_size = status.max;
+	}
+
+	/*
+	 * If the snapshot has been invalidated or we failed to parse
+	 * the status string. Report the full status string to syslog.
+	 */
+	if (status.invalid || !status.max) {
+		syslog(LOG_ERR, "Snapshot %s changed state to: %s\n", device, params);
+		state->percent_check = 0;
+		goto out;
+	}
+
+	percent = 100 * status.used / status.max;
+	if (percent >= state->percent_check) {
+		/* Usage has raised more than CHECK_STEP since the last
+		   time. Run actions. */
+		state->percent_check = (percent / CHECK_STEP) * CHECK_STEP + CHECK_STEP;
+
+		if (percent >= WARNING_THRESH) /* Print a warning to syslog. */
+			syslog(LOG_WARNING, "Snapshot %s is now %i%% full.\n", device, percent);
+		/* Try to extend the snapshot, in accord with user-set policies */
+		if (!_extend(state->cmd_str))
+			syslog(LOG_ERR, "Failed to extend snapshot %s.\n", device);
+	}
+
+out:
+	dmeventd_lvm2_unlock();
+}
+
+int register_device(const char *device,
+		    const char *uuid __attribute__((unused)),
+		    int major __attribute__((unused)),
+		    int minor __attribute__((unused)),
+		    void **private)
+{
+	struct dso_state *state;
+
+	if (!dmeventd_lvm2_init())
+		goto out;
+
+	if (!(state = dm_zalloc(sizeof(*state))))
+		goto bad;
+
+	if (!dmeventd_lvm2_command(dmeventd_lvm2_pool(),
+                                   state->cmd_str, sizeof(state->cmd_str),
+				   "lvextend --use-policies", device))
+		goto bad;
+
+	state->percent_check = CHECK_MINIMUM;
+	state->known_size = 0;
+	*private = state;
+
+	syslog(LOG_INFO, "Monitoring snapshot %s\n", device);
+
+	return 1;
+bad:
+	dm_free(state);
+	dmeventd_lvm2_exit();
+out:
+	syslog(LOG_ERR, "Failed to monitor snapshot %s.\n", device);
+
+	return 0;
+}
+
+int unregister_device(const char *device,
+		      const char *uuid __attribute__((unused)),
+		      int major __attribute__((unused)),
+		      int minor __attribute__((unused)),
+		      void **private)
+{
+	struct dso_state *state = *private;
+
+	syslog(LOG_INFO, "No longer monitoring snapshot %s\n", device);
+	dm_free(state);
+	dmeventd_lvm2_exit();
+
+	return 1;
+}

daemons/dmeventd/plugins/thin/.exported_symbols

@@ -0,0 +1,3 @@
+process_event
+register_device
+unregister_device

daemons/dmeventd/plugins/thin/Makefile.in

@@ -0,0 +1,36 @@
+#
+# Copyright (C) 2011 Red Hat, Inc. All rights reserved.
+#
+# This file is part of LVM2.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU General Public License v.2.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+INCLUDES += -I$(top_srcdir)/tools -I$(top_srcdir)/daemons/dmeventd/plugins/lvm2
+CLDFLAGS += -L$(top_builddir)/tools -L$(top_builddir)/daemons/dmeventd/plugins/lvm2
+
+SOURCES = dmeventd_thin.c
+
+LIB_NAME = libdevmapper-event-lvm2thin
+LIB_SHARED = $(LIB_NAME).$(LIB_SUFFIX)
+LIB_VERSION = $(LIB_VERSION_LVM)
+
+CFLOW_LIST = $(SOURCES)
+CFLOW_LIST_TARGET = $(LIB_NAME).cflow
+
+include $(top_builddir)/make.tmpl
+
+LIBS += -ldevmapper-event-lvm2 -ldevmapper
+
+install_lvm2: install_dm_plugin
+
+install: install_lvm2

daemons/dmeventd/plugins/thin/dmeventd_thin.c

@@ -0,0 +1,288 @@
+/*
+ * Copyright (C) 2011 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "lib.h"
+
+#include "lvm2cmd.h"
+#include "errors.h"
+#include "libdevmapper-event.h"
+#include "dmeventd_lvm.h"
+
+#include "lvm-string.h"
+
+#include <sys/wait.h>
+#include <syslog.h> /* FIXME Replace syslog with multilog */
+/* FIXME Missing openlog? */
+
+/* First warning when thin is 80% full. */
+#define WARNING_THRESH 80
+/* Run a check every 5%. */
+#define CHECK_STEP 5
+/* Do not bother checking thins less than 50% full. */
+#define CHECK_MINIMUM 50
+
+#define UMOUNT_COMMAND "/bin/umount"
+
+#define THIN_DEBUG 0
+
+struct dso_state {
+	struct dm_pool *mem;
+	int metadata_percent_check;
+	int data_percent_check;
+	uint64_t known_metadata_size;
+	uint64_t known_data_size;
+	char cmd_str[1024];
+};
+
+static int _extend(struct dso_state *state)
+{
+#if THIN_DEBUG
+	syslog(LOG_INFO, "dmeventd executes: %s.\n", state->cmd_str);
+#endif
+	return (dmeventd_lvm2_run(state->cmd_str) == ECMD_PROCESSED);
+}
+
+#if 0
+static int _run(const char *cmd, ...)
+{
+        va_list ap;
+        int argc = 1; /* for argv[0], i.e. cmd */
+        int i = 0;
+        const char **argv;
+        pid_t pid = fork();
+        int status;
+
+        if (pid == 0) { /* child */
+                va_start(ap, cmd);
+                while (va_arg(ap, const char *))
+                        ++argc;
+                va_end(ap);
+
+                /* + 1 for the terminating NULL */
+                argv = alloca(sizeof(const char *) * (argc + 1));
+
+                argv[0] = cmd;
+                va_start(ap, cmd);
+                while ((argv[++i] = va_arg(ap, const char *)));
+                va_end(ap);
+
+                execvp(cmd, (char **)argv);
+                syslog(LOG_ERR, "Failed to execute %s: %s.\n", cmd, strerror(errno));
+                exit(127);
+        }
+
+        if (pid > 0) { /* parent */
+                if (waitpid(pid, &status, 0) != pid)
+                        return 0; /* waitpid failed */
+                if (!WIFEXITED(status) || WEXITSTATUS(status))
+                        return 0; /* the child failed */
+        }
+
+        if (pid < 0)
+                return 0; /* fork failed */
+
+        return 1; /* all good */
+}
+
+/* FIXME: all thin pool users needs to be here */
+static void _umount(const char *device, int major, int minor)
+{
+	FILE *mounts;
+	char buffer[4096];
+	char *words[3];
+	struct stat st;
+
+	if (!(mounts = fopen("/proc/mounts", "r"))) {
+		syslog(LOG_ERR, "Could not read /proc/mounts. Not umounting %s.\n", device);
+		return;
+	}
+
+	while (!feof(mounts)) {
+		/* read a line of /proc/mounts */
+		if (!fgets(buffer, sizeof(buffer), mounts))
+			break; /* eof, likely */
+
+		/* words[0] is the mount point and words[1] is the device path */
+		dm_split_words(buffer, 3, 0, words);
+
+		/* find the major/minor of the device */
+		if (stat(words[0], &st))
+			continue; /* can't stat, skip this one */
+
+		if (S_ISBLK(st.st_mode) &&
+		    (int) major(st.st_rdev) == major &&
+		    (int) minor(st.st_rdev) == minor) {
+			syslog(LOG_ERR, "Unmounting invalid thin %s from %s.\n", device, words[1]);
+			if (!_run(UMOUNT_COMMAND, "-fl", words[1], NULL))
+				syslog(LOG_ERR, "Failed to umount thin %s from %s: %s.\n",
+				       device, words[1], strerror(errno));
+		}
+	}
+
+	if (fclose(mounts))
+		syslog(LOG_ERR, "Failed to close /proc/mounts.\n");
+}
+#endif
+
+void process_event(struct dm_task *dmt,
+		   enum dm_event_mask event __attribute__((unused)),
+		   void **private)
+{
+	const char *device = dm_task_get_name(dmt);
+	int percent;
+	struct dso_state *state = *private;
+	struct dm_status_thin_pool *tps = NULL;
+	void *next = NULL;
+	uint64_t start, length;
+	char *target_type = NULL;
+	char *params;
+
+#if 0
+	/* No longer monitoring, waiting for remove */
+	if (!state->meta_percent_check && !state->data_percent_check)
+		return;
+#endif
+	dmeventd_lvm2_lock();
+
+	dm_get_next_target(dmt, next, &start, &length, &target_type, &params);
+
+	if (!target_type || (strcmp(target_type, "thin-pool") != 0)) {
+		syslog(LOG_ERR, "Invalid target type.\n");
+		goto out;
+	}
+
+	if (!dm_get_status_thin_pool(state->mem, params, &tps)) {
+		syslog(LOG_ERR, "Failed to parse status.\n");
+#if 0
+		/* FIXME hmm what we should do? */
+		struct dm_info info;
+		if (dm_task_get_info(dmt, &info)) {
+			dmeventd_lvm2_unlock();
+			_umount(device, info.major, info.minor);
+		} /* else; too bad, but this is best-effort thing... */
+#endif
+		goto out;
+	}
+
+#if THIN_DEBUG
+	syslog(LOG_INFO, "%p: Got status %" PRIu64 " / %" PRIu64
+	       " %" PRIu64  " / %" PRIu64 ".\n", state,
+	       tps->used_meta_blocks, tps->total_meta_blocks,
+	       tps->used_data_blocks, tps->total_data_blocks);
+#endif
+
+	/* Thin pool size had changed. Clear the threshold. */
+	if (state->known_metadata_size != tps->total_metadata_blocks) {
+		state->metadata_percent_check = CHECK_MINIMUM;
+		state->known_metadata_size = tps->total_metadata_blocks;
+	}
+
+	if (state->known_data_size != tps->total_data_blocks) {
+		state->data_percent_check = CHECK_MINIMUM;
+		state->known_data_size = tps->total_data_blocks;
+	}
+
+	percent = 100 * tps->used_metadata_blocks / tps->total_metadata_blocks;
+	if (percent >= state->metadata_percent_check) {
+		/*
+		 * Usage has raised more than CHECK_STEP since the last
+		 * time. Run actions.
+		 */
+		state->metadata_percent_check = (percent / CHECK_STEP) * CHECK_STEP + CHECK_STEP;
+
+		/* FIXME: extension of metadata needs to be written! */
+		if (percent >= WARNING_THRESH) /* Print a warning to syslog. */
+			syslog(LOG_WARNING, "Thin metadata %s is now %i%% full.\n",
+			       device, percent);
+		 /* Try to extend the metadata, in accord with user-set policies */
+		if (!_extend(state))
+			syslog(LOG_ERR, "Failed to extend thin metadata %s.\n",
+			       device);
+		/* FIXME: hmm READ-ONLY switch should happen in error path */
+	}
+
+	percent = 100 * tps->used_data_blocks / tps->total_data_blocks;
+	if (percent >= state->data_percent_check) {
+		/*
+		 * Usage has raised more than CHECK_STEP since
+		 * the last time. Run actions.
+		 */
+		state->data_percent_check = (percent / CHECK_STEP) * CHECK_STEP + CHECK_STEP;
+
+		if (percent >= WARNING_THRESH) /* Print a warning to syslog. */
+			syslog(LOG_WARNING, "Thin %s is now %i%% full.\n", device, percent);
+		/* Try to extend the thin data, in accord with user-set policies */
+		if (!_extend(state))
+			syslog(LOG_ERR, "Failed to extend thin %s.\n", device);
+		/* FIXME: hmm READ-ONLY switch should happen in error path */
+	}
+out:
+	if (tps)
+		dm_pool_free(state->mem, tps);
+
+	dmeventd_lvm2_unlock();
+}
+
+int register_device(const char *device,
+		    const char *uuid __attribute__((unused)),
+		    int major __attribute__((unused)),
+		    int minor __attribute__((unused)),
+		    void **private)
+{
+	struct dm_pool *statemem = NULL;
+	struct dso_state *state;
+
+	if (!dmeventd_lvm2_init())
+		goto bad;
+
+	if (!(statemem = dm_pool_create("thin_pool_state", 2048)) ||
+	    !(state = dm_pool_zalloc(statemem, sizeof(*state))) ||
+	    !dmeventd_lvm2_command(statemem, state->cmd_str,
+				   sizeof(state->cmd_str),
+				   "lvextend --use-policies",
+				   device)) {
+		if (statemem)
+			dm_pool_destroy(statemem);
+		dmeventd_lvm2_exit();
+		goto bad;
+	}
+
+	state->mem = statemem;
+	state->metadata_percent_check = CHECK_MINIMUM;
+	state->data_percent_check = CHECK_MINIMUM;
+	*private = state;
+
+	syslog(LOG_INFO, "Monitoring thin %s.\n", device);
+
+	return 1;
+bad:
+	syslog(LOG_ERR, "Failed to monitor thin %s.\n", device);
+
+	return 0;
+}
+
+int unregister_device(const char *device,
+		      const char *uuid __attribute__((unused)),
+		      int major __attribute__((unused)),
+		      int minor __attribute__((unused)),
+		      void **private)
+{
+	struct dso_state *state = *private;
+
+	syslog(LOG_INFO, "No longer monitoring thin %s.\n", device);
+	dm_pool_destroy(state->mem);
+	dmeventd_lvm2_exit();
+
+	return 1;
+}

daemons/lvmetad/Makefile.in

@@ -0,0 +1,53 @@
+# Copyright (C) 2011 Red Hat, Inc. All rights reserved.
+#
+# This file is part of the device-mapper userspace tools.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU Lesser General Public License v.2.1.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+SOURCES = lvmetad-core.c
+SOURCES2 = testclient.c
+
+TARGETS = lvmetad lvmetad-testclient
+
+.PHONY: install_lvmetad
+
+INCLUDES += -I$(top_srcdir)/daemons/common
+
+CFLOW_LIST = $(SOURCES)
+CFLOW_LIST_TARGET = $(LIB_NAME).cflow
+CFLOW_TARGET = lvmetad
+
+include $(top_builddir)/make.tmpl
+
+LIBS += -ldevmapper -ldaemon $(PTHREAD_LIBS)
+
+lvmetad: lvmetad-core.o
+	$(CC) $(CFLAGS) $(LDFLAGS) -L$(top_builddir)/daemons/common -o $@ lvmetad-core.o \
+	$(DL_LIBS) $(LVMLIBS) $(LIBS) -rdynamic
+
+# TODO: No idea. No idea how to test either.
+#ifneq ("$(CFLOW_CMD)", "")
+#CFLOW_SOURCES = $(addprefix $(srcdir)/, $(SOURCES))
+#-include $(top_builddir)/libdm/libdevmapper.cflow
+#-include $(top_builddir)/lib/liblvm-internal.cflow
+#-include $(top_builddir)/lib/liblvm2cmd.cflow
+#-include $(top_builddir)/daemons/dmeventd/$(LIB_NAME).cflow
+#-include $(top_builddir)/daemons/dmeventd/plugins/mirror/$(LIB_NAME)-lvm2mirror.cflow
+#endif
+
+install_lvmetad: lvmetad
+	$(INSTALL_PROGRAM) -D $< $(sbindir)/$(<F)
+
+install_lvm2: install_lvmetad
+
+install: install_lvm2

daemons/lvmetad/lvmetad-client.h

@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) 2011 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _LVM_LVMETAD_CLIENT_H
+#define _LVM_LVMETAD_CLIENT_H
+
+#include "daemon-client.h"
+#include "metadata-exported.h"
+
+/* Different types of replies we may get from lvmetad. */
+
+typedef struct {
+	daemon_reply r;
+	const char **uuids; /* NULL terminated array */
+} lvmetad_uuidlist;
+
+typedef struct {
+	daemon_reply r;
+	struct dm_config_tree *cft;
+} lvmetad_vg;
+
+static inline daemon_handle lvmetad_open();
+static inline void lvmetad_close(daemon_handle h);
+
+/* Get a list of VG UUIDs that match a given VG name. */
+lvmetad_uuidlist lvmetad_lookup_vgname(daemon_handle h, const char *name);
+
+/* Get the metadata of a single VG, identified by UUID. */
+lvmetad_vg lvmetad_get_vg(daemon_handle h, const char *uuid);
+
+/*
+ * Add and remove PVs on demand. Udev-driven systems will use this interface
+ * instead of scanning.
+ */
+daemon_reply lvmetad_add_pv(daemon_handle h, const char *pv_uuid, const char *mda_content);
+daemon_reply lvmetad_remove_pv(daemon_handle h, const char *pv_uuid);
+
+/* Trigger a full disk scan, throwing away all caches. XXX do we eventually want
+ * this? Probalby not yet, anyway.
+ *     daemon_reply lvmetad_rescan(daemon_handle h);
+ */
+
+/*
+ * Update the version of metadata of a volume group. The VG has to be locked for
+ * writing for this, and the VG metadata here has to match whatever has been
+ * written to the disk (under this lock). This initially avoids the requirement
+ * for lvmetad to write to disk (in later revisions, lvmetad_supersede_vg may
+ * also do the writing, or we probably add another function to do that).
+ */
+daemon_reply lvmetad_supersede_vg(daemon_handle h, struct volume_group *vg);
+
+/* Implementation of inline functions */
+
+static inline daemon_handle lvmetad_open(const char *socket)
+{
+	/* TODO configurable */
+	daemon_info lvmetad_info = {
+		.path = "lvmetad",
+		.socket = socket ?: "/var/run/lvm/lvmetad.socket",
+		.autostart = 1
+	};
+
+	return daemon_open(lvmetad_info);
+}
+
+static inline void lvmetad_close(daemon_handle h)
+{
+	return daemon_close(h);
+}
+
+#endif

daemons/lvmetad/lvmetad-core.c

@@ -0,0 +1,984 @@
+#define _GNU_SOURCE
+#define _XOPEN_SOURCE 500  /* pthread */
+
+#include <assert.h>
+#include <pthread.h>
+#include <malloc.h>
+#include <stdint.h>
+#include <unistd.h>
+
+#include "configure.h"
+#include "libdevmapper.h"
+#include "daemon-server.h"
+
+typedef struct {
+	struct dm_hash_table *pvid_to_pvmeta;
+	struct dm_hash_table *device_to_pvid; /* shares locks with above */
+
+	struct dm_hash_table *vgid_to_metadata;
+	struct dm_hash_table *vgid_to_vgname;
+	struct dm_hash_table *vgname_to_vgid;
+	struct dm_hash_table *pvid_to_vgid;
+	struct {
+		struct dm_hash_table *vg;
+		pthread_mutex_t pvid_to_pvmeta;
+		pthread_mutex_t vgid_to_metadata;
+		pthread_mutex_t pvid_to_vgid;
+	} lock;
+} lvmetad_state;
+
+__attribute__ ((format(printf, 1, 2)))
+static void debug(const char *fmt, ...) {
+	va_list ap;
+	va_start(ap, fmt);
+	fprintf(stderr, "[D %lu] ", pthread_self());
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+}
+
+static int debug_cft_line(const char *line, void *baton) {
+	fprintf(stderr, "| %s\n", line);
+	return 0;
+}
+
+static void debug_cft(const char *id, struct dm_config_node *n) {
+	debug("%s\n", id);
+	dm_config_write_node(n, &debug_cft_line, NULL);
+}
+
+static void lock_pvid_to_pvmeta(lvmetad_state *s) {
+	pthread_mutex_lock(&s->lock.pvid_to_pvmeta); }
+static void unlock_pvid_to_pvmeta(lvmetad_state *s) {
+	pthread_mutex_unlock(&s->lock.pvid_to_pvmeta); }
+
+static void lock_vgid_to_metadata(lvmetad_state *s) {
+	pthread_mutex_lock(&s->lock.vgid_to_metadata); }
+static void unlock_vgid_to_metadata(lvmetad_state *s) {
+	pthread_mutex_unlock(&s->lock.vgid_to_metadata); }
+
+static void lock_pvid_to_vgid(lvmetad_state *s) {
+	pthread_mutex_lock(&s->lock.pvid_to_vgid); }
+static void unlock_pvid_to_vgid(lvmetad_state *s) {
+	pthread_mutex_unlock(&s->lock.pvid_to_vgid); }
+
+/*
+ * TODO: It may be beneficial to clean up the vg lock hash from time to time,
+ * since if we have many "rogue" requests for nonexistent things, we will keep
+ * allocating memory that we never release. Not good.
+ */
+static struct dm_config_tree *lock_vg(lvmetad_state *s, const char *id) {
+	pthread_mutex_t *vg;
+	struct dm_config_tree *cft;
+
+	lock_vgid_to_metadata(s);
+	vg = dm_hash_lookup(s->lock.vg, id);
+	if (!vg) {
+		pthread_mutexattr_t rec;
+		pthread_mutexattr_init(&rec);
+		pthread_mutexattr_settype(&rec, PTHREAD_MUTEX_RECURSIVE_NP);
+		vg = malloc(sizeof(pthread_mutex_t));
+		pthread_mutex_init(vg, &rec);
+		dm_hash_insert(s->lock.vg, id, vg);
+	}
+	// debug("lock VG %s\n", id);
+	pthread_mutex_lock(vg);
+	cft = dm_hash_lookup(s->vgid_to_metadata, id);
+	unlock_vgid_to_metadata(s);
+	return cft;
+}
+
+static void unlock_vg(lvmetad_state *s, const char *id) {
+	// debug("unlock VG %s\n", id);
+	lock_vgid_to_metadata(s); /* someone might be changing the s->lock.vg structure right
+				   * now, so avoid stepping on each other's toes */
+	pthread_mutex_unlock(dm_hash_lookup(s->lock.vg, id));
+	unlock_vgid_to_metadata(s);
+}
+
+static struct dm_config_node *pvs(struct dm_config_node *vg)
+{
+	struct dm_config_node *pv = dm_config_find_node(vg, "metadata/physical_volumes");
+	if (pv)
+		pv = pv->child;
+	return pv;
+}
+
+/*
+ * TODO: This set_flag function is pretty generic and might make sense in a
+ * library here or there.
+ */
+static int set_flag(struct dm_config_tree *cft, struct dm_config_node *parent,
+		     const char *field, const char *flag, int want) {
+	struct dm_config_value *value = NULL, *pred = NULL;
+	struct dm_config_node *node = dm_config_find_node(parent->child, field);
+	struct dm_config_value *new;
+
+	if (node)
+		value = node->v;
+
+	while (value && value->type != DM_CFG_EMPTY_ARRAY && strcmp(value->v.str, flag)) {
+		pred = value;
+		value = value->next;
+	}
+
+	if (value && want)
+		return 1;
+
+	if (!value && !want)
+		return 1;
+
+	if (value && !want) {
+		if (pred) {
+			pred->next = value->next;
+		} else if (value == node->v && value->next) {
+			node->v = value->next;
+		} else {
+			node->v->type = DM_CFG_EMPTY_ARRAY;
+		}
+	}
+
+	if (!value && want) {
+		if (!node) {
+			node = dm_config_create_node(cft, field);
+			node->sib = parent->child;
+			node->v = dm_config_create_value(cft);
+			node->v->type = DM_CFG_EMPTY_ARRAY;
+			node->parent = parent;
+			parent->child = node;
+		}
+		if (!(new = dm_config_create_value(cft))) {
+			/* FIXME error reporting */
+			return 0;
+		}
+		new->type = DM_CFG_STRING;
+		new->v.str = flag;
+		new->next = node->v;
+		node->v = new;
+	}
+
+	return 1;
+}
+
+static struct dm_config_node *make_config_node(struct dm_config_tree *cft,
+					       const char *key,
+					       struct dm_config_node *parent,
+					       struct dm_config_node *pre_sib)
+{
+	struct dm_config_node *cn = dm_config_create_node(cft, key);
+	cn->parent = parent;
+	cn->sib = NULL;
+	cn->v = NULL;
+	cn->child = NULL;
+
+	if (parent && parent->child && !pre_sib) { /* find the last one */
+		pre_sib = parent->child;
+		while (pre_sib && pre_sib->sib) pre_sib = pre_sib->sib;
+	}
+
+	if (parent && !parent->child)
+		parent->child = cn;
+	if (pre_sib)
+		pre_sib->sib = cn;
+
+	return cn;
+}
+
+static struct dm_config_node *make_text_node(struct dm_config_tree *cft,
+					     const char *key,
+					     const char *value,
+					     struct dm_config_node *parent,
+					     struct dm_config_node *pre_sib)
+{
+	struct dm_config_node *cn = make_config_node(cft, key, parent, pre_sib);
+	cn->v = dm_config_create_value(cft);
+	cn->v->type = DM_CFG_STRING;
+	cn->v->v.str = value;
+	return cn;
+}
+
+static struct dm_config_node *make_int_node(struct dm_config_tree *cft,
+					    const char *key,
+					    int64_t value,
+					    struct dm_config_node *parent,
+					    struct dm_config_node *pre_sib)
+{
+	struct dm_config_node *cn = make_config_node(cft, key, parent, pre_sib);
+	cn->v = dm_config_create_value(cft);
+	cn->v->type = DM_CFG_INT;
+	cn->v->v.i = value;
+	return cn;
+}
+
+static void filter_metadata(struct dm_config_node *vg) {
+	struct dm_config_node *pv = pvs(vg);
+	while (pv) {
+		struct dm_config_node *item = pv->child;
+		while (item) {
+			/* Remove the advisory device nodes. */
+			if (item->sib && !strcmp(item->sib->key, "device"))
+				item->sib = item->sib->sib;
+			item = item->sib;
+		}
+		pv = pv->sib;
+	}
+	vg->sib = NULL; /* Drop any trailing garbage. */
+}
+
+/* Either the "big" vgs lock, or a per-vg lock needs to be held before entering
+ * this function. */
+static int update_pv_status(lvmetad_state *s,
+			    struct dm_config_tree *cft,
+			    struct dm_config_node *vg, int act)
+{
+	struct dm_config_node *pv;
+	int complete = 1;
+
+	lock_pvid_to_pvmeta(s);
+	pv = pvs(vg);
+	while (pv) {
+		const char *uuid = dm_config_find_str(pv->child, "id", NULL);
+		struct dm_config_tree *pvmeta = dm_hash_lookup(s->pvid_to_pvmeta, uuid);
+		if (act) {
+			set_flag(cft, pv, "status", "MISSING", !pvmeta);
+			if (pvmeta) {
+				// debug_cft("PV META", pvmeta->root);
+				make_int_node(cft, "device",
+					      dm_config_find_int(pvmeta->root, "pvmeta/device", 0),
+					      pv, NULL);
+			}
+		}
+		if (!pvmeta) {
+			complete = 0;
+			if (!act) { /* optimisation */
+				unlock_pvid_to_pvmeta(s);
+				return complete;
+			}
+		}
+		pv = pv->sib;
+	}
+	unlock_pvid_to_pvmeta(s);
+
+	return complete;
+}
+
+static struct dm_config_node *make_pv_node(lvmetad_state *s, const char *pvid,
+					   struct dm_config_tree *cft,
+					   struct dm_config_node *parent,
+					   struct dm_config_node *pre_sib)
+{
+	struct dm_config_tree *pvmeta = dm_hash_lookup(s->pvid_to_pvmeta, pvid);
+	const char *vgid = dm_hash_lookup(s->pvid_to_vgid, pvid), *vgname = NULL;
+
+	if (!pvmeta)
+		return NULL;
+
+	if (vgid) {
+		lock_vgid_to_metadata(s); // XXX
+		vgname = dm_hash_lookup(s->vgid_to_vgname, vgid);
+		unlock_vgid_to_metadata(s);
+	}
+
+	/* Nick the pvmeta config tree. */
+	struct dm_config_node *pv = dm_config_clone_node(cft, pvmeta->root, 0);
+	if (pre_sib)
+		pre_sib->sib = pv;
+	if (parent && !parent->child)
+		parent->child = pv;
+	pv->parent = parent;
+
+	/* Add the "variable" bits to it. */
+	struct dm_config_node *cn = NULL;
+
+	if (vgid && strcmp(vgid, "#orphan"))
+		cn = make_text_node(cft, "vgid", vgid, pv, cn);
+	if (vgname)
+		cn = make_text_node(cft, "vgname", vgname, pv, cn);
+
+	return pv;
+}
+
+static response pv_list(lvmetad_state *s, request r)
+{
+	struct dm_config_node *cn = NULL, *cn_pvs;
+	response res = { .buffer = NULL };
+	res.cft = dm_config_create();
+
+	/* The response field */
+	res.cft->root = make_text_node(res.cft, "response", "OK", NULL, NULL);
+	cn_pvs = make_config_node(res.cft, "physical_volumes", NULL, res.cft->root);
+
+	lock_pvid_to_pvmeta(s);
+
+	struct dm_hash_node *n = dm_hash_get_first(s->pvid_to_pvmeta);
+	while (n) {
+		const char *id = dm_hash_get_key(s->pvid_to_pvmeta, n);
+		cn = make_pv_node(s, id, res.cft, cn_pvs, cn);
+		n = dm_hash_get_next(s->pvid_to_pvmeta, n);
+	}
+
+	unlock_pvid_to_pvmeta(s);
+
+	// debug_cft("PV LIST", res.cft->root);
+
+	return res;
+}
+
+static response pv_lookup(lvmetad_state *s, request r)
+{
+	const char *pvid = daemon_request_str(r, "uuid", NULL);
+	if (!pvid)
+		return daemon_reply_simple("failed", "reason = %s", "need PVID", NULL);
+
+	response res = { .buffer = NULL };
+	res.cft = dm_config_create();
+	res.cft->root = make_text_node(res.cft, "response", "OK", NULL, NULL);
+
+	struct dm_config_node *pv;
+
+	lock_pvid_to_pvmeta(s);
+	pv = make_pv_node(s, pvid, res.cft, NULL, res.cft->root);
+	if (!pv) {
+		unlock_pvid_to_pvmeta(s);
+		return daemon_reply_simple("failed", "reason = %s", "PV not found", NULL);
+	}
+
+	pv->key = "physical_volume";
+	unlock_pvid_to_pvmeta(s);
+
+	// debug_cft("PV LOOKUP", res.cft->root);
+
+	return res;
+}
+
+static response vg_list(lvmetad_state *s, request r)
+{
+	struct dm_config_node *cn, *cn_vgs, *cn_last = NULL;
+	response res = { .buffer = NULL };
+	res.cft = dm_config_create();
+
+	/* The response field */
+	res.cft->root = cn = dm_config_create_node(res.cft, "response");
+	cn->parent = res.cft->root;
+	cn->v = dm_config_create_value(res.cft);
+	cn->v->type = DM_CFG_STRING;
+	cn->v->v.str = "OK";
+
+	cn_vgs = cn = cn->sib = dm_config_create_node(res.cft, "volume_groups");
+	cn->parent = res.cft->root;
+	cn->v = NULL;
+	cn->child = NULL;
+
+	lock_vgid_to_metadata(s);
+
+	struct dm_hash_node *n = dm_hash_get_first(s->vgid_to_vgname);
+	while (n) {
+		const char *id = dm_hash_get_key(s->vgid_to_vgname, n),
+			 *name = dm_hash_get_data(s->vgid_to_vgname, n);
+
+		cn = dm_config_create_node(res.cft, id);
+		if (cn_last)
+			cn_last->sib = cn;
+
+		cn->parent = cn_vgs;
+		cn->sib = NULL;
+		cn->v = NULL;
+
+		cn->child = dm_config_create_node(res.cft, "name");
+		cn->child->parent = cn;
+		cn->child->sib = 0;
+		cn->child->v = dm_config_create_value(res.cft);
+		cn->child->v->type = DM_CFG_STRING;
+		cn->child->v->v.str = name;
+
+		if (!cn_vgs->child)
+			cn_vgs->child = cn;
+		cn_last = cn;
+
+		n = dm_hash_get_next(s->vgid_to_vgname, n);
+	}
+
+	unlock_vgid_to_metadata(s);
+
+	return res;
+}
+
+static response vg_lookup(lvmetad_state *s, request r)
+{
+	struct dm_config_tree *cft;
+	struct dm_config_node *metadata, *n;
+	response res = { .buffer = NULL };
+
+	const char *uuid = daemon_request_str(r, "uuid", NULL),
+		   *name = daemon_request_str(r, "name", NULL);
+
+	debug("vg_lookup: uuid = %s, name = %s\n", uuid, name);
+
+	if (!uuid || !name) {
+		lock_vgid_to_metadata(s);
+		if (name && !uuid)
+			uuid = dm_hash_lookup(s->vgname_to_vgid, (void *)name);
+		if (uuid && !name)
+			name = dm_hash_lookup(s->vgid_to_vgname, (void *)uuid);
+		unlock_vgid_to_metadata(s);
+	}
+
+	debug("vg_lookup: updated uuid = %s, name = %s\n", uuid, name);
+
+	if (!uuid)
+		return daemon_reply_simple("failed", "reason = %s", "VG not found", NULL);
+
+	cft = lock_vg(s, uuid);
+	if (!cft || !cft->root) {
+		unlock_vg(s, uuid);
+		return daemon_reply_simple("failed", "reason = %s", "UUID not found", NULL);
+	}
+
+	metadata = cft->root;
+	res.cft = dm_config_create();
+
+	/* The response field */
+	res.cft->root = n = dm_config_create_node(res.cft, "response");
+	n->parent = res.cft->root;
+	n->v->type = DM_CFG_STRING;
+	n->v->v.str = "OK";
+
+	n = n->sib = dm_config_create_node(res.cft, "name");
+	n->parent = res.cft->root;
+	n->v->type = DM_CFG_STRING;
+	n->v->v.str = name;
+
+	/* The metadata section */
+	n = n->sib = dm_config_clone_node(res.cft, metadata, 1);
+	n->parent = res.cft->root;
+	res.error = 0;
+	unlock_vg(s, uuid);
+
+	update_pv_status(s, res.cft, n, 1); /* FIXME report errors */
+
+	// debug_cft("METADATA", n);
+
+	return res;
+}
+
+static int compare_value(struct dm_config_value *a, struct dm_config_value *b)
+{
+	int r = 0;
+
+	if (a->type > b->type)
+		return 1;
+	if (a->type < b->type)
+		return -1;
+
+	switch (a->type) {
+	case DM_CFG_STRING: r = strcmp(a->v.str, b->v.str); break;
+	case DM_CFG_FLOAT: r = (a->v.f == b->v.f) ? 0 : (a->v.f > b->v.f) ? 1 : -1; break;
+	case DM_CFG_INT: r = (a->v.i == b->v.i) ? 0 : (a->v.i > b->v.i) ? 1 : -1; break;
+	case DM_CFG_EMPTY_ARRAY: return 0;
+	}
+
+	if (r == 0 && a->next && b->next)
+		r = compare_value(a->next, b->next);
+	return r;
+}
+
+static int compare_config(struct dm_config_node *a, struct dm_config_node *b)
+{
+	int result = 0;
+	if (a->v && b->v)
+		result = compare_value(a->v, b->v);
+	if (a->v && !b->v)
+		result = 1;
+	if (!a->v && b->v)
+		result = -1;
+	if (a->child && b->child)
+		result = compare_config(a->child, b->child);
+
+	if (result) {
+		debug("config inequality at %s / %s\n", a->key, b->key);
+		return result;
+	}
+
+	if (a->sib && b->sib)
+		result = compare_config(a->sib, b->sib);
+	if (a->sib && !b->sib)
+		result = 1;
+	if (!a->sib && b->sib)
+		result = -1;
+
+	return result;
+}
+
+static int vg_remove_if_missing(lvmetad_state *s, const char *vgid);
+
+/* You need to be holding the pvid_to_vgid lock already to call this. */
+static int update_pvid_to_vgid(lvmetad_state *s, struct dm_config_tree *vg,
+			       const char *vgid, int nuke_empty)
+{
+	struct dm_config_node *pv = pvs(vg->root);
+	struct dm_hash_table *to_check = dm_hash_create(32);
+
+	if (!vgid)
+		return 0;
+
+	while (pv) {
+		const char *pvid = dm_config_find_str(pv->child, "id", NULL);
+		const char *vgid_old = dm_hash_lookup(s->pvid_to_vgid, pvid);
+		if (vgid_old && nuke_empty)
+			dm_hash_insert(to_check, vgid_old, (void*) 1);
+		dm_hash_insert(s->pvid_to_vgid, pvid, (void *) vgid);
+		debug("remap PV %s to VG %s\n", pvid, vgid);
+		pv = pv->sib;
+	}
+
+	struct dm_hash_node *n = dm_hash_get_first(to_check);
+
+	while (n) {
+		const char *check_vgid = dm_hash_get_key(to_check, n);
+		lock_vg(s, check_vgid);
+		vg_remove_if_missing(s, check_vgid);
+		unlock_vg(s, check_vgid);
+		n = dm_hash_get_next(to_check, n);
+	}
+
+	dm_hash_destroy(to_check);
+
+	return 1;
+}
+
+/* A pvid map lock needs to be held if update_pvids = 1. */
+static int remove_metadata(lvmetad_state *s, const char *vgid, int update_pvids)
+{
+	struct dm_config_tree *old;
+	const char *oldname;
+	lock_vgid_to_metadata(s);
+	old = dm_hash_lookup(s->vgid_to_metadata, vgid);
+	oldname = dm_hash_lookup(s->vgid_to_vgname, vgid);
+	unlock_vgid_to_metadata(s);
+
+	if (!old)
+		return 0;
+
+	if (update_pvids)
+		update_pvid_to_vgid(s, old, "#orphan", 0);
+	/* need to update what we have since we found a newer version */
+	dm_hash_remove(s->vgid_to_metadata, vgid);
+	dm_hash_remove(s->vgid_to_vgname, vgid);
+	dm_hash_remove(s->vgname_to_vgid, oldname);
+	dm_config_destroy(old);
+	return 1;
+}
+
+/* The VG must be locked. */
+static int vg_remove_if_missing(lvmetad_state *s, const char *vgid)
+{
+	if (!vgid)
+		return 0;
+
+	struct dm_config_tree *vg = dm_hash_lookup(s->vgid_to_metadata, vgid);
+	if (!vg)
+		return 1;
+
+	struct dm_config_node *pv = pvs(vg->root);
+
+	int missing = 1;
+
+	lock_pvid_to_pvmeta(s);
+
+	while (pv) {
+		const char *pvid = dm_config_find_str(pv->child, "id", NULL);
+		const char *vgid_check = dm_hash_lookup(s->pvid_to_vgid, pvid);
+		if (dm_hash_lookup(s->pvid_to_pvmeta, pvid) &&
+		    vgid_check && !strcmp(vgid, vgid_check))
+			missing = 0; /* at least one PV is around */
+		pv = pv->sib;
+	}
+
+	if (missing) {
+		debug("nuking VG %s\n", vgid);
+		remove_metadata(s, vgid, 0);
+	}
+
+	unlock_pvid_to_pvmeta(s);
+
+	return 1;
+}
+
+/* No locks need to be held. The pointers are never used outside of the scope of
+ * this function, so they can be safely destroyed after update_metadata returns
+ * (anything that might have been retained is copied). */
+static int update_metadata(lvmetad_state *s, const char *name, const char *_vgid,
+			   struct dm_config_node *metadata)
+{
+	struct dm_config_tree *cft;
+	struct dm_config_tree *old;
+	int retval = 0;
+	int seq;
+	int haveseq = -1;
+	const char *oldname = NULL;
+	const char *vgid;
+
+	lock_vgid_to_metadata(s);
+	old = dm_hash_lookup(s->vgid_to_metadata, _vgid);
+	lock_vg(s, _vgid);
+	unlock_vgid_to_metadata(s);
+
+	seq = dm_config_find_int(metadata, "metadata/seqno", -1);
+
+	if (old) {
+		haveseq = dm_config_find_int(old->root, "metadata/seqno", -1);
+		oldname = dm_hash_lookup(s->vgid_to_vgname, _vgid);
+		assert(oldname);
+	}
+
+	if (seq < 0)
+		goto out;
+
+	filter_metadata(metadata); /* sanitize */
+
+	if (seq == haveseq) {
+		retval = 1;
+		if (compare_config(metadata, old->root))
+			retval = 0;
+		debug("Not updating metadata for %s at %d (%s)\n", _vgid, haveseq,
+		      retval ? "ok" : "MISMATCH");
+		if (!retval) {
+			debug_cft("OLD: ", old->root);
+			debug_cft("NEW: ", metadata);
+		}
+		goto out;
+	}
+
+	if (seq < haveseq) {
+		debug("Refusing to update metadata for %s at %d to %d\n", _vgid, haveseq, seq);
+		/* TODO: notify the client that their metadata is out of date? */
+		retval = 1;
+		goto out;
+	}
+
+	cft = dm_config_create();
+	cft->root = dm_config_clone_node(cft, metadata, 0);
+
+	vgid = dm_config_find_str(cft->root, "metadata/id", NULL);
+
+	if (!vgid || !name) {
+		debug("Name '%s' or uuid '%s' missing!\n", name, vgid);
+		goto out;
+	}
+
+	lock_pvid_to_vgid(s);
+
+	if (haveseq >= 0 && haveseq < seq) {
+		debug("Updating metadata for %s at %d to %d\n", _vgid, haveseq, seq);
+		/* temporarily orphan all of our PVs */
+		remove_metadata(s, vgid, 1);
+	}
+
+	// debug_cft("METADATA", metadata);
+	lock_vgid_to_metadata(s);
+	dm_hash_insert(s->vgid_to_metadata, vgid, cft);
+	debug("Mapping %s to %s\n", vgid, name);
+	dm_hash_insert(s->vgid_to_vgname, vgid, dm_pool_strdup(dm_config_memory(cft), name));
+	dm_hash_insert(s->vgname_to_vgid, name, (void *)vgid);
+	unlock_vgid_to_metadata(s);
+
+	update_pvid_to_vgid(s, cft, vgid, 1);
+
+	unlock_pvid_to_vgid(s);
+	retval = 1;
+out:
+	unlock_vg(s, _vgid);
+	return retval;
+}
+
+static response pv_gone(lvmetad_state *s, request r)
+{
+	int found = 0;
+	const char *pvid = daemon_request_str(r, "uuid", NULL);
+	int64_t device = daemon_request_int(r, "device", 0);
+
+	debug("pv_gone: %s / %lld\n", pvid, device);
+	debug_cft("PV_GONE", r.cft->root);
+
+	lock_pvid_to_pvmeta(s);
+	if (!pvid && device > 0)
+		pvid = dm_hash_lookup_binary(s->device_to_pvid, &device, sizeof(device));
+	if (!pvid) {
+		unlock_pvid_to_pvmeta(s);
+		return daemon_reply_simple("failed", "reason = %s", "device not in cache", NULL);
+	}
+
+	debug("pv_gone (updated): %s / %lld\n", pvid, device);
+
+	struct dm_config_tree *pvmeta = dm_hash_lookup(s->pvid_to_pvmeta, pvid);
+	dm_hash_remove_binary(s->device_to_pvid, &device, sizeof(device));
+	dm_hash_remove(s->pvid_to_pvmeta, pvid);
+	vg_remove_if_missing(s, dm_hash_lookup(s->pvid_to_vgid, pvid));
+	unlock_pvid_to_pvmeta(s);
+
+	if (pvmeta) {
+		dm_config_destroy(pvmeta);
+		return daemon_reply_simple("OK", NULL);
+	} else
+		return daemon_reply_simple("failed", "reason = %s", "PVID does not exist", NULL);
+}
+
+static response pv_found(lvmetad_state *s, request r)
+{
+	struct dm_config_node *metadata = dm_config_find_node(r.cft->root, "metadata");
+	const char *pvid = daemon_request_str(r, "pvmeta/id", NULL);
+	const char *vgname = daemon_request_str(r, "vgname", NULL);
+	const char *vgid = daemon_request_str(r, "metadata/id", NULL);
+	struct dm_config_node *pvmeta = dm_config_find_node(r.cft->root, "pvmeta");
+	uint64_t device;
+
+	int complete = 0, orphan = 0;
+
+	// debug_cft("INCOMING PV", r.cft->root);
+
+	if (!pvid)
+		return daemon_reply_simple("failed", "reason = %s", "need PV UUID", NULL);
+	if (!pvmeta)
+		return daemon_reply_simple("failed", "reason = %s", "need PV metadata", NULL);
+
+	if (!dm_config_get_uint64(pvmeta, "pvmeta/device", &device))
+		return daemon_reply_simple("failed", "reason = %s", "need PV device number", NULL);
+
+	debug("pv_found %s, vgid = %s, device = %lld\n", pvid, vgid, device);
+
+	lock_pvid_to_pvmeta(s);
+	{
+		struct dm_config_tree *cft = dm_config_create();
+		cft->root = dm_config_clone_node(cft, pvmeta, 0);
+		const char *pvid_dup = dm_config_find_str(cft->root, "pvmeta/id", NULL);
+		dm_hash_insert(s->pvid_to_pvmeta, pvid, cft);
+		dm_hash_insert_binary(s->device_to_pvid, &device, sizeof(device), (void*)pvid_dup);
+	}
+	unlock_pvid_to_pvmeta(s);
+
+	if (metadata) {
+		if (!vgid)
+			return daemon_reply_simple("failed", "reason = %s", "need VG UUID", NULL);
+		debug("obtained vgid = %s, vgname = %s", vgid, vgname);
+		if (!vgname)
+			return daemon_reply_simple("failed", "reason = %s", "need VG name", NULL);
+		if (daemon_request_int(r, "metadata/seqno", -1) < 0)
+			return daemon_reply_simple("failed", "reason = %s", "need VG seqno", NULL);
+
+		if (!update_metadata(s, vgname, vgid, metadata))
+			return daemon_reply_simple("failed", "reason = %s",
+						   "metadata update failed", NULL);
+	} else {
+		lock_pvid_to_vgid(s);
+		vgid = dm_hash_lookup(s->pvid_to_vgid, pvid);
+		unlock_pvid_to_vgid(s);
+	}
+
+	if (vgid) {
+		struct dm_config_tree *cft = lock_vg(s, vgid);
+		if (cft) {
+			complete = update_pv_status(s, cft, cft->root, 0);
+		} else if (!strcmp(vgid, "#orphan")) {
+			orphan = 1;
+		} else {
+			unlock_vg(s, vgid);
+			return daemon_reply_simple("failed", "reason = %s",
+						   "internal treason!", NULL);
+		}
+		unlock_vg(s, vgid);
+	}
+
+	return daemon_reply_simple("OK",
+				   "status = %s", orphan ? "orphan" :
+				                     (complete ? "complete" : "partial"),
+				   "vgid = %s", vgid ? vgid : "#orphan",
+				   NULL);
+}
+
+static response vg_update(lvmetad_state *s, request r)
+{
+	struct dm_config_node *metadata = dm_config_find_node(r.cft->root, "metadata");
+	const char *vgid = daemon_request_str(r, "metadata/id", NULL);
+	const char *vgname = daemon_request_str(r, "vgname", NULL);
+	if (metadata) {
+		if (!vgid)
+			return daemon_reply_simple("failed", "reason = %s", "need VG UUID", NULL);
+		if (!vgname)
+			return daemon_reply_simple("failed", "reason = %s", "need VG name", NULL);
+		if (daemon_request_int(r, "metadata/seqno", -1) < 0)
+			return daemon_reply_simple("failed", "reason = %s", "need VG seqno", NULL);
+
+		/* TODO defer metadata update here; add a separate vg_commit
+		 * call; if client does not commit, die */
+		if (!update_metadata(s, vgname, vgid, metadata))
+			return daemon_reply_simple("failed", "reason = %s",
+						   "metadata update failed", NULL);
+	}
+	return daemon_reply_simple("OK", NULL);
+}
+
+static response vg_remove(lvmetad_state *s, request r)
+{
+	const char *vgid = daemon_request_str(r, "uuid", NULL);
+
+	if (!vgid)
+		return daemon_reply_simple("failed", "reason = %s", "need VG UUID", NULL);
+
+	fprintf(stderr, "vg_remove: %s\n", vgid);
+
+	lock_pvid_to_vgid(s);
+	remove_metadata(s, vgid, 1);
+	unlock_pvid_to_vgid(s);
+
+	return daemon_reply_simple("OK", NULL);
+}
+
+static response handler(daemon_state s, client_handle h, request r)
+{
+	lvmetad_state *state = s.private;
+	const char *rq = daemon_request_str(r, "request", "NONE");
+
+	/*
+	 * TODO Add a stats call, with transaction count/rate, time since last
+	 * update &c.
+	 */
+	if (!strcmp(rq, "pv_found"))
+		return pv_found(state, r);
+
+	if (!strcmp(rq, "pv_gone"))
+		return pv_gone(state, r);
+
+	if (!strcmp(rq, "pv_lookup"))
+		return pv_lookup(state, r);
+
+	if (!strcmp(rq, "vg_update"))
+		return vg_update(state, r);
+
+	if (!strcmp(rq, "vg_remove"))
+		return vg_remove(state, r);
+
+	if (!strcmp(rq, "vg_lookup"))
+		return vg_lookup(state, r);
+
+	if (!strcmp(rq, "pv_list")) {
+		return pv_list(state, r);
+	}
+
+	if (!strcmp(rq, "vg_list"))
+		return vg_list(state, r);
+
+	return daemon_reply_simple("failed", "reason = %s", "no such request", NULL);
+}
+
+static int init(daemon_state *s)
+{
+	pthread_mutexattr_t rec;
+	lvmetad_state *ls = s->private;
+
+	ls->pvid_to_pvmeta = dm_hash_create(32);
+	ls->device_to_pvid = dm_hash_create(32);
+	ls->vgid_to_metadata = dm_hash_create(32);
+	ls->vgid_to_vgname = dm_hash_create(32);
+	ls->pvid_to_vgid = dm_hash_create(32);
+	ls->vgname_to_vgid = dm_hash_create(32);
+	ls->lock.vg = dm_hash_create(32);
+	pthread_mutexattr_init(&rec);
+	pthread_mutexattr_settype(&rec, PTHREAD_MUTEX_RECURSIVE_NP);
+	pthread_mutex_init(&ls->lock.pvid_to_pvmeta, &rec);
+	pthread_mutex_init(&ls->lock.vgid_to_metadata, &rec);
+	pthread_mutex_init(&ls->lock.pvid_to_vgid, NULL);
+
+	debug("initialised state: vgid_to_metadata = %p\n", ls->vgid_to_metadata);
+	if (!ls->pvid_to_vgid || !ls->vgid_to_metadata)
+		return 0;
+
+	/* if (ls->initial_registrations)
+	   _process_initial_registrations(ds->initial_registrations); */
+
+	return 1;
+}
+
+static int fini(daemon_state *s)
+{
+	lvmetad_state *ls = s->private;
+	struct dm_hash_node *n = dm_hash_get_first(ls->vgid_to_metadata);
+
+	debug("fini\n");
+	while (n) {
+		dm_config_destroy(dm_hash_get_data(ls->vgid_to_metadata, n));
+		n = dm_hash_get_next(ls->vgid_to_metadata, n);
+	}
+
+	n = dm_hash_get_first(ls->lock.vg);
+	while (n) {
+		pthread_mutex_destroy(dm_hash_get_data(ls->lock.vg, n));
+		free(dm_hash_get_data(ls->lock.vg, n));
+		n = dm_hash_get_next(ls->lock.vg, n);
+	}
+
+	dm_hash_destroy(ls->lock.vg);
+	dm_hash_destroy(ls->pvid_to_pvmeta);
+	dm_hash_destroy(ls->device_to_pvid);
+	dm_hash_destroy(ls->vgid_to_metadata);
+	dm_hash_destroy(ls->pvid_to_vgid);
+	return 1;
+}
+
+static void usage(char *prog, FILE *file)
+{
+	fprintf(file, "Usage:\n"
+		"%s [-V] [-h] [-d] [-d] [-d] [-f]\n\n"
+		"   -V       Show version of lvmetad\n"
+		"   -h       Show this help information\n"
+		"   -d       Log debug messages to syslog (-d, -dd, -ddd)\n"
+		"   -R       Replace a running lvmetad instance, loading its data\n"
+		"   -f       Don't fork, run in the foreground\n\n", prog);
+}
+
+int main(int argc, char *argv[])
+{
+	signed char opt;
+	daemon_state s = { .private = NULL };
+	lvmetad_state ls;
+	int _restart = 0;
+
+	s.name = "lvmetad";
+	s.private = &ls;
+	s.daemon_init = init;
+	s.daemon_fini = fini;
+	s.handler = handler;
+	s.socket_path = getenv("LVM_LVMETAD_SOCKET");
+	if (!s.socket_path)
+		s.socket_path = DEFAULT_RUN_DIR "/lvmetad.socket";
+	s.pidfile = DEFAULT_RUN_DIR "/lvmetad.pid";
+        s.log_level = 0;
+
+	// use getopt_long
+	while ((opt = getopt(argc, argv, "?fhVdRs:")) != EOF) {
+		switch (opt) {
+		case 'h':
+			usage(argv[0], stdout);
+			exit(0);
+		case '?':
+			usage(argv[0], stderr);
+			exit(0);
+		case 'R':
+			_restart++;
+			break;
+		case 'f':
+			s.foreground = 1;
+			break;
+		case 'd':
+			s.log_level++;
+			break;
+		case 's': // --socket
+			s.socket_path = optarg;
+			break;
+		case 'V':
+			printf("lvmetad version 0\n");
+			exit(1);
+		}
+	}
+
+	daemon_start(s);
+	return 0;
+}

daemons/lvmetad/test.sh

@@ -0,0 +1,16 @@
+#!/bin/bash
+
+export LD_LIBRARY_PATH="$1"
+
+test -n "$2" && {
+    rm -f /var/run/lvmetad.{socket,pid}
+    chmod +rx lvmetad
+    valgrind ./lvmetad -f &
+    PID=$!
+    sleep 1
+    ./testclient
+    kill $PID
+    exit 0
+}
+
+sudo ./test.sh "$1" .

daemons/lvmetad/testclient.c

@@ -0,0 +1,127 @@
+#include "lvmetad-client.h"
+#include "label.h"
+#include "lvmcache.h"
+#include "metadata.h"
+
+const char *uuid1 = "abcd-efgh";
+const char *uuid2 = "bbcd-efgh";
+const char *vgid = "yada-yada";
+const char *uuid3 = "cbcd-efgh";
+
+const char *metadata2 = "{\n"
+	"id = \"yada-yada\"\n"
+	"seqno = 15\n"
+	"status = [\"READ\", \"WRITE\"]\n"
+	"flags = []\n"
+	"extent_size = 8192\n"
+	"physical_volumes {\n"
+	"    pv0 {\n"
+	"        id = \"abcd-efgh\"\n"
+	"    }\n"
+	"    pv1 {\n"
+	"        id = \"bbcd-efgh\"\n"
+	"    }\n"
+	"    pv2 {\n"
+	"        id = \"cbcd-efgh\"\n"
+	"    }\n"
+	"}\n"
+	"}\n";
+
+void _handle_reply(daemon_reply reply) {
+	const char *repl = daemon_reply_str(reply, "response", NULL);
+	const char *status = daemon_reply_str(reply, "status", NULL);
+	const char *vgid = daemon_reply_str(reply, "vgid", NULL);
+
+	fprintf(stderr, "[C] REPLY: %s\n", repl);
+	if (!strcmp(repl, "failed"))
+		fprintf(stderr, "[C] REASON: %s\n", daemon_reply_str(reply, "reason", "unknown"));
+	if (vgid)
+		fprintf(stderr, "[C] VGID: %s\n", vgid);
+	if (status)
+		fprintf(stderr, "[C] STATUS: %s\n", status);
+	daemon_reply_destroy(reply);
+}
+
+void _pv_add(daemon_handle h, const char *uuid, const char *metadata)
+{
+	daemon_reply reply = daemon_send_simple(h, "pv_add", "uuid = %s", uuid,
+						             "metadata = %b", metadata,
+						             NULL);
+	_handle_reply(reply);
+}
+
+int scan(daemon_handle h, char *fn) {
+	struct device *dev = dev_cache_get(fn, NULL);
+
+	struct label *label;
+	if (!label_read(dev, &label, 0)) {
+		fprintf(stderr, "[C] no label found on %s\n", fn);
+		return;
+	}
+
+	char uuid[64];
+	id_write_format(dev->pvid, uuid, 64);
+	fprintf(stderr, "[C] found PV: %s\n", uuid);
+	struct lvmcache_info *info = (struct lvmcache_info *) label->info;
+	struct physical_volume pv = { 0, };
+
+	if (!(info->fmt->ops->pv_read(info->fmt, dev_name(dev), &pv, 0))) {
+		fprintf(stderr, "[C] Failed to read PV %s", dev_name(dev));
+		return;
+	}
+
+	struct format_instance_ctx fic;
+	struct format_instance *fid = info->fmt->ops->create_instance(info->fmt, &fic);
+	struct metadata_area *mda;
+	struct volume_group *vg = NULL;
+	dm_list_iterate_items(mda, &info->mdas) {
+		struct volume_group *this = mda->ops->vg_read(fid, "", mda);
+		if (this && !vg || this->seqno > vg->seqno)
+			vg = this;
+	}
+	if (vg) {
+		char *buf = NULL;
+		/* TODO. This is not entirely correct, since export_vg_to_buffer
+		 * adds trailing garbage to the buffer. We may need to use
+		 * export_vg_to_config_tree and format the buffer ourselves. It
+		 * does, however, work for now, since the garbage is well
+		 * formatted and has no conflicting keys with the rest of the
+		 * request.  */
+		export_vg_to_buffer(vg, &buf);
+		daemon_reply reply =
+			daemon_send_simple(h, "pv_add", "uuid = %s", uuid,
+					      "metadata = %b", strchr(buf, '{'),
+					      NULL);
+		_handle_reply(reply);
+	}
+}
+
+void _dump_vg(daemon_handle h, const char *uuid)
+{
+	daemon_reply reply = daemon_send_simple(h, "vg_by_uuid", "uuid = %s", uuid, NULL);
+	fprintf(stderr, "[C] reply buffer: %s\n", reply.buffer);
+	daemon_reply_destroy(reply);
+}
+
+int main(int argc, char **argv) {
+	daemon_handle h = lvmetad_open();
+
+	if (argc > 1) {
+		int i;
+		struct cmd_context *cmd = create_toolcontext(0, NULL, 0, 0);
+		for (i = 1; i < argc; ++i) {
+			const char *uuid = NULL;
+			scan(h, argv[i]);
+		}
+		destroy_toolcontext(cmd);
+		return 0;
+	}
+
+	_pv_add(h, uuid1, NULL);
+	_pv_add(h, uuid2, metadata2);
+	_dump_vg(h, vgid);
+	_pv_add(h, uuid3, NULL);
+
+	daemon_close(h);
+	return 0;
+}

doc/Makefile.in

@@ -0,0 +1,31 @@
+#
+# Copyright (C) 2004-2010 Red Hat, Inc. All rights reserved.
+#
+# This file is part of LVM2.
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions
+# of the GNU General Public License v.2.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software Foundation,
+# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+top_builddir = @top_builddir@
+
+CONFSRC=example.conf
+CONFDEST=lvm.conf
+
+include $(top_builddir)/make.tmpl
+
+install_lvm2: $(CONFSRC)
+	@if [ ! -e $(confdir)/$(CONFDEST) ]; then \
+		echo "$(INSTALL_WDATA) -D $< $(confdir)/$(CONFDEST)"; \
+		$(INSTALL_WDATA) -D $< $(confdir)/$(CONFDEST); \
+	fi
+
+install: install_lvm2
+
+DISTCLEAN_TARGETS += $(CONFSRC)

doc/README

@@ -1 +0,0 @@
-Wow!  This is really incredible documentation!

doc/example.conf.in

@@ -0,0 +1,753 @@
+# This is an example configuration file for the LVM2 system.
+# It contains the default settings that would be used if there was no
+# @DEFAULT_SYS_DIR@/lvm.conf file.
+#
+# Refer to 'man lvm.conf' for further information including the file layout.
+#
+# To put this file in a different directory and override @DEFAULT_SYS_DIR@ set
+# the environment variable LVM_SYSTEM_DIR before running the tools.
+#
+# N.B. Take care that each setting only appears once if uncommenting
+# example settings in this file.
+
+
+# This section allows you to configure which block devices should
+# be used by the LVM system.
+devices {
+
+    # Where do you want your volume groups to appear ?
+    dir = "/dev"
+
+    # An array of directories that contain the device nodes you wish
+    # to use with LVM2.
+    scan = [ "/dev" ]
+
+    # If set, the cache of block device nodes with all associated symlinks
+    # will be constructed out of the existing udev database content.
+    # This avoids using and opening any inapplicable non-block devices or
+    # subdirectories found in the device directory. This setting is applied
+    # to udev-managed device directory only, other directories will be scanned
+    # fully. LVM2 needs to be compiled with udev support for this setting to
+    # take effect. N.B. Any device node or symlink not managed by udev in
+    # udev directory will be ignored with this setting on.
+    obtain_device_list_from_udev = 1
+
+    # If several entries in the scanned directories correspond to the
+    # same block device and the tools need to display a name for device,
+    # all the pathnames are matched against each item in the following
+    # list of regular expressions in turn and the first match is used.
+    preferred_names = [ ]
+
+    # Try to avoid using undescriptive /dev/dm-N names, if present.
+    # preferred_names = [ "^/dev/mpath/", "^/dev/mapper/mpath", "^/dev/[hs]d" ]
+
+    # A filter that tells LVM2 to only use a restricted set of devices.
+    # The filter consists of an array of regular expressions.  These
+    # expressions can be delimited by a character of your choice, and
+    # prefixed with either an 'a' (for accept) or 'r' (for reject).
+    # The first expression found to match a device name determines if
+    # the device will be accepted or rejected (ignored).  Devices that
+    # don't match any patterns are accepted.
+
+    # Be careful if there there are symbolic links or multiple filesystem 
+    # entries for the same device as each name is checked separately against
+    # the list of patterns.  The effect is that if the first pattern in the 
+    # list to match a name is an 'a' pattern for any of the names, the device
+    # is accepted; otherwise if the first pattern in the list to match a name
+    # is an 'r' pattern for any of the names it is rejected; otherwise it is
+    # accepted.
+
+    # Don't have more than one filter line active at once: only one gets used.
+
+    # Run vgscan after you change this parameter to ensure that
+    # the cache file gets regenerated (see below).
+    # If it doesn't do what you expect, check the output of 'vgscan -vvvv'.
+
+
+    # By default we accept every block device:
+    filter = [ "a/.*/" ]
+
+    # Exclude the cdrom drive
+    # filter = [ "r|/dev/cdrom|" ]
+
+    # When testing I like to work with just loopback devices:
+    # filter = [ "a/loop/", "r/.*/" ]
+
+    # Or maybe all loops and ide drives except hdc:
+    # filter =[ "a|loop|", "r|/dev/hdc|", "a|/dev/ide|", "r|.*|" ]
+
+    # Use anchors if you want to be really specific
+    # filter = [ "a|^/dev/hda8$|", "r/.*/" ]
+
+    # The results of the filtering are cached on disk to avoid
+    # rescanning dud devices (which can take a very long time).
+    # By default this cache is stored in the @DEFAULT_SYS_DIR@/@DEFAULT_CACHE_SUBDIR@ directory
+    # in a file called '.cache'.
+    # It is safe to delete the contents: the tools regenerate it.
+    # (The old setting 'cache' is still respected if neither of
+    # these new ones is present.)
+    cache_dir = "@DEFAULT_SYS_DIR@/@DEFAULT_CACHE_SUBDIR@"
+    cache_file_prefix = ""
+
+    # You can turn off writing this cache file by setting this to 0.
+    write_cache_state = 1
+
+    # Advanced settings.
+
+    # List of pairs of additional acceptable block device types found 
+    # in /proc/devices with maximum (non-zero) number of partitions.
+    # types = [ "fd", 16 ]
+
+    # If sysfs is mounted (2.6 kernels) restrict device scanning to 
+    # the block devices it believes are valid.
+    # 1 enables; 0 disables.
+    sysfs_scan = 1
+
+    # By default, LVM2 will ignore devices used as component paths
+    # of device-mapper multipath devices.
+    # 1 enables; 0 disables.
+    multipath_component_detection = 1
+
+    # By default, LVM2 will ignore devices used as components of
+    # software RAID (md) devices by looking for md superblocks.
+    # 1 enables; 0 disables.
+    md_component_detection = 1
+
+    # By default, if a PV is placed directly upon an md device, LVM2
+    # will align its data blocks with the md device's stripe-width.
+    # 1 enables; 0 disables.
+    md_chunk_alignment = 1
+
+    # Default alignment of the start of a data area in MB.  If set to 0,
+    # a value of 64KB will be used.  Set to 1 for 1MiB, 2 for 2MiB, etc.
+    # default_data_alignment = @DEFAULT_DATA_ALIGNMENT@
+
+    # By default, the start of a PV's data area will be a multiple of
+    # the 'minimum_io_size' or 'optimal_io_size' exposed in sysfs.
+    # - minimum_io_size - the smallest request the device can perform
+    #   w/o incurring a read-modify-write penalty (e.g. MD's chunk size)
+    # - optimal_io_size - the device's preferred unit of receiving I/O
+    #   (e.g. MD's stripe width)
+    # minimum_io_size is used if optimal_io_size is undefined (0).
+    # If md_chunk_alignment is enabled, that detects the optimal_io_size.
+    # This setting takes precedence over md_chunk_alignment.
+    # 1 enables; 0 disables.
+    data_alignment_detection = 1
+
+    # Alignment (in KB) of start of data area when creating a new PV.
+    # md_chunk_alignment and data_alignment_detection are disabled if set.
+    # Set to 0 for the default alignment (see: data_alignment_default)
+    # or page size, if larger.
+    data_alignment = 0
+
+    # By default, the start of the PV's aligned data area will be shifted by
+    # the 'alignment_offset' exposed in sysfs.  This offset is often 0 but
+    # may be non-zero; e.g.: certain 4KB sector drives that compensate for
+    # windows partitioning will have an alignment_offset of 3584 bytes
+    # (sector 7 is the lowest aligned logical block, the 4KB sectors start
+    # at LBA -1, and consequently sector 63 is aligned on a 4KB boundary).
+    # But note that pvcreate --dataalignmentoffset will skip this detection.
+    # 1 enables; 0 disables.
+    data_alignment_offset_detection = 1
+
+    # If, while scanning the system for PVs, LVM2 encounters a device-mapper
+    # device that has its I/O suspended, it waits for it to become accessible.
+    # Set this to 1 to skip such devices.  This should only be needed
+    # in recovery situations.
+    ignore_suspended_devices = 0
+
+    # During each LVM operation errors received from each device are counted.
+    # If the counter of a particular device exceeds the limit set here, no
+    # further I/O is sent to that device for the remainder of the respective
+    # operation. Setting the parameter to 0 disables the counters altogether.
+    disable_after_error_count = 0
+
+    # Allow use of pvcreate --uuid without requiring --restorefile.
+    require_restorefile_with_uuid = 1
+
+    # Minimum size (in KB) of block devices which can be used as PVs.
+    # In a clustered environment all nodes must use the same value.
+    # Any value smaller than 512KB is ignored.
+
+    # Ignore devices smaller than 2MB such as floppy drives.
+    pv_min_size = 2048
+
+    # The original built-in setting was 512 up to and including version 2.02.84.
+    # pv_min_size = 512
+
+    # Issue discards to a logical volumes's underlying physical volume(s) when
+    # the logical volume is no longer using the physical volumes' space (e.g.
+    # lvremove, lvreduce, etc).  Discards inform the storage that a region is
+    # no longer in use.  Storage that supports discards advertise the protocol
+    # specific way discards should be issued by the kernel (TRIM, UNMAP, or
+    # WRITE SAME with UNMAP bit set).  Not all storage will support or benefit
+    # from discards but SSDs and thinly provisioned LUNs generally do.  If set
+    # to 1, discards will only be issued if both the storage and kernel provide
+    # support.
+    # 1 enables; 0 disables.
+    issue_discards = 0
+}
+
+# This section allows you to configure the way in which LVM selects
+# free space for its Logical Volumes.
+#allocation {
+#    When searching for free space to extend an LV, the "cling"
+#    allocation policy will choose space on the same PVs as the last
+#    segment of the existing LV.  If there is insufficient space and a
+#    list of tags is defined here, it will check whether any of them are
+#    attached to the PVs concerned and then seek to match those PV tags
+#    between existing extents and new extents.
+#    Use the special tag "@*" as a wildcard to match any PV tag.
+#    
+#    Example: LVs are mirrored between two sites within a single VG.
+#    PVs are tagged with either @site1 or @site2 to indicate where
+#    they are situated.
+#
+#    cling_tag_list = [ "@site1", "@site2" ]
+#    cling_tag_list = [ "@*" ]
+#
+#    Changes made in version 2.02.85 extended the reach of the 'cling'
+#    policies to detect more situations where data can be grouped
+#    onto the same disks.  Set this to 0 to revert to the previous
+#    algorithm.
+#
+#    maximise_cling = 1
+#
+#    Set to 1 to guarantee that mirror logs will always be placed on 
+#    different PVs from the mirror images.  This was the default
+#    until version 2.02.85.
+#
+#    mirror_logs_require_separate_pvs = 0
+#
+#    Set to 1 to guarantee that thin pool metadata will always
+#    be placed on different PVs from the pool data.
+#
+#    thin_pool_metadata_require_separate_pvs = 0
+#}
+
+# This section that allows you to configure the nature of the
+# information that LVM2 reports.
+log {
+
+    # Controls the messages sent to stdout or stderr.
+    # There are three levels of verbosity, 3 being the most verbose.
+    verbose = 0
+
+    # Should we send log messages through syslog?
+    # 1 is yes; 0 is no.
+    syslog = 1
+
+    # Should we log error and debug messages to a file?
+    # By default there is no log file.
+    #file = "/var/log/lvm2.log"
+
+    # Should we overwrite the log file each time the program is run?
+    # By default we append.
+    overwrite = 0
+
+    # What level of log messages should we send to the log file and/or syslog?
+    # There are 6 syslog-like log levels currently in use - 2 to 7 inclusive.
+    # 7 is the most verbose (LOG_DEBUG).
+    level = 0
+
+    # Format of output messages
+    # Whether or not (1 or 0) to indent messages according to their severity
+    indent = 1
+
+    # Whether or not (1 or 0) to display the command name on each line output
+    command_names = 0
+
+    # A prefix to use before the message text (but after the command name,
+    # if selected).  Default is two spaces, so you can see/grep the severity
+    # of each message.
+    prefix = "  "
+
+    # To make the messages look similar to the original LVM tools use:
+    #   indent = 0
+    #   command_names = 1
+    #   prefix = " -- "
+
+    # Set this if you want log messages during activation.
+    # Don't use this in low memory situations (can deadlock).
+    # activation = 0
+}
+
+# Configuration of metadata backups and archiving.  In LVM2 when we
+# talk about a 'backup' we mean making a copy of the metadata for the
+# *current* system.  The 'archive' contains old metadata configurations.
+# Backups are stored in a human readeable text format.
+backup {
+
+    # Should we maintain a backup of the current metadata configuration ?
+    # Use 1 for Yes; 0 for No.
+    # Think very hard before turning this off!
+    backup = 1
+
+    # Where shall we keep it ?
+    # Remember to back up this directory regularly!
+    backup_dir = "@DEFAULT_SYS_DIR@/@DEFAULT_BACKUP_SUBDIR@"
+
+    # Should we maintain an archive of old metadata configurations.
+    # Use 1 for Yes; 0 for No.
+    # On by default.  Think very hard before turning this off.
+    archive = 1
+
+    # Where should archived files go ?
+    # Remember to back up this directory regularly!
+    archive_dir = "@DEFAULT_SYS_DIR@/@DEFAULT_ARCHIVE_SUBDIR@"
+
+    # What is the minimum number of archive files you wish to keep ?
+    retain_min = 10
+
+    # What is the minimum time you wish to keep an archive file for ?
+    retain_days = 30
+}
+
+# Settings for the running LVM2 in shell (readline) mode.
+shell {
+
+    # Number of lines of history to store in ~/.lvm_history
+    history_size = 100
+}
+
+
+# Miscellaneous global LVM2 settings
+global {
+
+    # The file creation mask for any files and directories created.
+    # Interpreted as octal if the first digit is zero.
+    umask = 077
+
+    # Allow other users to read the files
+    #umask = 022
+
+    # Enabling test mode means that no changes to the on disk metadata
+    # will be made.  Equivalent to having the -t option on every
+    # command.  Defaults to off.
+    test = 0
+
+    # Default value for --units argument
+    units = "h"
+
+    # Since version 2.02.54, the tools distinguish between powers of
+    # 1024 bytes (e.g. KiB, MiB, GiB) and powers of 1000 bytes (e.g.
+    # KB, MB, GB).
+    # If you have scripts that depend on the old behaviour, set this to 0
+    # temporarily until you update them.
+    si_unit_consistency = 1
+
+    # Whether or not to communicate with the kernel device-mapper.
+    # Set to 0 if you want to use the tools to manipulate LVM metadata 
+    # without activating any logical volumes.
+    # If the device-mapper kernel driver is not present in your kernel
+    # setting this to 0 should suppress the error messages.
+    activation = 1
+
+    # If we can't communicate with device-mapper, should we try running 
+    # the LVM1 tools?
+    # This option only applies to 2.4 kernels and is provided to help you
+    # switch between device-mapper kernels and LVM1 kernels.
+    # The LVM1 tools need to be installed with .lvm1 suffices
+    # e.g. vgscan.lvm1 and they will stop working after you start using
+    # the new lvm2 on-disk metadata format.
+    # The default value is set when the tools are built.
+    # fallback_to_lvm1 = 0
+
+    # The default metadata format that commands should use - "lvm1" or "lvm2".
+    # The command line override is -M1 or -M2.
+    # Defaults to "lvm2".
+    # format = "lvm2"
+
+    # Location of proc filesystem
+    proc = "/proc"
+
+    # Type of locking to use. Defaults to local file-based locking (1).
+    # Turn locking off by setting to 0 (dangerous: risks metadata corruption
+    # if LVM2 commands get run concurrently).
+    # Type 2 uses the external shared library locking_library.
+    # Type 3 uses built-in clustered locking.
+    # Type 4 uses read-only locking which forbids any operations that might 
+    # change metadata.
+    locking_type = 1
+
+    # Set to 0 to fail when a lock request cannot be satisfied immediately.
+    wait_for_locks = 1
+
+    # If using external locking (type 2) and initialisation fails,
+    # with this set to 1 an attempt will be made to use the built-in
+    # clustered locking.
+    # If you are using a customised locking_library you should set this to 0.
+    fallback_to_clustered_locking = 1
+
+    # If an attempt to initialise type 2 or type 3 locking failed, perhaps
+    # because cluster components such as clvmd are not running, with this set
+    # to 1 an attempt will be made to use local file-based locking (type 1).
+    # If this succeeds, only commands against local volume groups will proceed.
+    # Volume Groups marked as clustered will be ignored.
+    fallback_to_local_locking = 1
+
+    # Local non-LV directory that holds file-based locks while commands are
+    # in progress.  A directory like /tmp that may get wiped on reboot is OK.
+    locking_dir = "@DEFAULT_LOCK_DIR@"
+
+    # Whenever there are competing read-only and read-write access requests for
+    # a volume group's metadata, instead of always granting the read-only
+    # requests immediately, delay them to allow the read-write requests to be
+    # serviced.  Without this setting, write access may be stalled by a high
+    # volume of read-only requests.
+    # NB. This option only affects locking_type = 1 viz. local file-based
+    # locking.
+    prioritise_write_locks = 1
+
+    # Other entries can go here to allow you to load shared libraries
+    # e.g. if support for LVM1 metadata was compiled as a shared library use
+    #   format_libraries = "liblvm2format1.so" 
+    # Full pathnames can be given.
+
+    # Search this directory first for shared libraries.
+    #   library_dir = "/lib"
+
+    # The external locking library to load if locking_type is set to 2.
+    #   locking_library = "liblvm2clusterlock.so"
+
+    # Treat any internal errors as fatal errors, aborting the process that
+    # encountered the internal error. Please only enable for debugging.
+    abort_on_internal_errors = 0
+
+    # Check whether CRC is matching when parsed VG is used multiple times.
+    # This is useful to catch unexpected internal cached volume group
+    # structure modification. Please only enable for debugging.
+    detect_internal_vg_cache_corruption = 0
+
+    # If set to 1, no operations that change on-disk metadata will be permitted.
+    # Additionally, read-only commands that encounter metadata in need of repair
+    # will still be allowed to proceed exactly as if the repair had been 
+    # performed (except for the unchanged vg_seqno).
+    # Inappropriate use could mess up your system, so seek advice first!
+    metadata_read_only = 0
+
+    # 'mirror_segtype_default' defines which segtype will be used when the
+    # shorthand '-m' option is used for mirroring.  The possible options are:
+    #
+    # "mirror" - The original RAID1 implementation provided by LVM2/DM.  It is
+    # 	         characterized by a flexible log solution (core, disk, mirrored)
+    #		 and by the necessity to block I/O while reconfiguring in the
+    #		 event of a failure.  Snapshots of this type of RAID1 can be
+    #		 problematic.
+    #
+    # "raid1"  - This implementation leverages MD's RAID1 personality through
+    # 	       	 device-mapper.  It is characterized by a lack of log options.
+    #		 (A log is always allocated for every device and they are placed
+    #		 on the same device as the image - no separate devices are
+    #		 required.)  This mirror implementation does not require I/O
+    #		 to be blocked in the kernel in the event of a failure.
+    #
+    # Specify the '--type <mirror|raid1>' option to override this default
+    # setting.
+    mirror_segtype_default = "mirror"
+
+    # The default format for displaying LV names in lvdisplay was changed 
+    # in version 2.02.89 to show the LV name and path separately.
+    # Previously this was always shown as /dev/vgname/lvname even when that
+    # was never a valid path in the /dev filesystem.
+    # Set to 1 to reinstate the previous format.
+    #
+    # lvdisplay_shows_full_device_path = 0
+}
+
+activation {
+    # Set to 1 to perform internal checks on the operations issued to
+    # libdevmapper.  Useful for debugging problems with activation.
+    # Some of the checks may be expensive, so it's best to use this
+    # only when there seems to be a problem.
+    checks = 0
+
+    # Set to 0 to disable udev synchronisation (if compiled into the binaries).
+    # Processes will not wait for notification from udev.
+    # They will continue irrespective of any possible udev processing
+    # in the background.  You should only use this if udev is not running
+    # or has rules that ignore the devices LVM2 creates.
+    # The command line argument --nodevsync takes precedence over this setting.
+    # If set to 1 when udev is not running, and there are LVM2 processes
+    # waiting for udev, run 'dmsetup udevcomplete_all' manually to wake them up.
+    udev_sync = 1
+
+    # Set to 0 to disable the udev rules installed by LVM2 (if built with
+    # --enable-udev_rules). LVM2 will then manage the /dev nodes and symlinks
+    # for active logical volumes directly itself.
+    # N.B. Manual intervention may be required if this setting is changed
+    # while any logical volumes are active.
+    udev_rules = 1
+
+    # Set to 1 for LVM2 to verify operations performed by udev. This turns on
+    # additional checks (and if necessary, repairs) on entries in the device
+    # directory after udev has completed processing its events. 
+    # Useful for diagnosing problems with LVM2/udev interactions.
+    verify_udev_operations = 0
+
+    # If set to 1 and if deactivation of an LV fails, perhaps because
+    # a process run from a quick udev rule temporarily opened the device,
+    # retry the operation for a few seconds before failing.
+    retry_deactivation = 1
+
+    # How to fill in missing stripes if activating an incomplete volume.
+    # Using "error" will make inaccessible parts of the device return
+    # I/O errors on access.  You can instead use a device path, in which 
+    # case, that device will be used to in place of missing stripes.
+    # But note that using anything other than "error" with mirrored 
+    # or snapshotted volumes is likely to result in data corruption.
+    missing_stripe_filler = "error"
+
+    # The linear target is an optimised version of the striped target
+    # that only handles a single stripe.  Set this to 0 to disable this
+    # optimisation and always use the striped target.
+    use_linear_target = 1
+
+    # How much stack (in KB) to reserve for use while devices suspended
+    # Prior to version 2.02.89 this used to be set to 256KB
+    reserved_stack = 64
+
+    # How much memory (in KB) to reserve for use while devices suspended
+    reserved_memory = 8192
+
+    # Nice value used while devices suspended
+    process_priority = -18
+
+    # If volume_list is defined, each LV is only activated if there is a
+    # match against the list.
+    #   "vgname" and "vgname/lvname" are matched exactly.
+    #   "@tag" matches any tag set in the LV or VG.
+    #   "@*" matches if any tag defined on the host is also set in the LV or VG
+    #
+    # volume_list = [ "vg1", "vg2/lvol1", "@tag1", "@*" ]
+
+    # If read_only_volume_list is defined, each LV that is to be activated 
+    # is checked against the list, and if it matches, it as activated
+    # in read-only mode.  (This overrides '--permission rw' stored in the
+    # metadata.)
+    #   "vgname" and "vgname/lvname" are matched exactly.
+    #   "@tag" matches any tag set in the LV or VG.
+    #   "@*" matches if any tag defined on the host is also set in the LV or VG
+    #
+    # read_only_volume_list = [ "vg1", "vg2/lvol1", "@tag1", "@*" ]
+
+    # Size (in KB) of each copy operation when mirroring
+    mirror_region_size = 512
+
+    # Setting to use when there is no readahead value stored in the metadata.
+    #
+    # "none" - Disable readahead.
+    # "auto" - Use default value chosen by kernel.
+    readahead = "auto"
+
+    # 'raid_fault_policy' defines how a device failure in a RAID logical
+    # volume is handled.  This includes logical volumes that have the following
+    # segment types: raid1, raid4, raid5*, and raid6*.
+    #
+    # In the event of a failure, the following policies will determine what
+    # actions are performed during the automated response to failures (when
+    # dmeventd is monitoring the RAID logical volume) and when 'lvconvert' is
+    # called manually with the options '--repair' and '--use-policies'.
+    #
+    # "warn"	- Use the system log to warn the user that a device in the RAID
+    # 		  logical volume has failed.  It is left to the user to run
+    #		  'lvconvert --repair' manually to remove or replace the failed
+    #		  device.  As long as the number of failed devices does not
+    #		  exceed the redundancy of the logical volume (1 device for
+    #		  raid4/5, 2 for raid6, etc) the logical volume will remain
+    #		  usable.
+    #
+    # "allocate" - Attempt to use any extra physical volumes in the volume
+    # 		  group as spares and replace faulty devices.
+    #
+    raid_fault_policy = "warn"
+
+    # 'mirror_image_fault_policy' and 'mirror_log_fault_policy' define
+    # how a device failure affecting a mirror (of "mirror" segment type) is
+    # handled.  A mirror is composed of mirror images (copies) and a log.
+    # A disk log ensures that a mirror does not need to be re-synced
+    # (all copies made the same) every time a machine reboots or crashes.
+    #
+    # In the event of a failure, the specified policy will be used to determine
+    # what happens. This applies to automatic repairs (when the mirror is being
+    # monitored by dmeventd) and to manual lvconvert --repair when
+    # --use-policies is given.
+    #
+    # "remove" - Simply remove the faulty device and run without it.  If
+    #            the log device fails, the mirror would convert to using
+    #            an in-memory log.  This means the mirror will not
+    #            remember its sync status across crashes/reboots and
+    #            the entire mirror will be re-synced.  If a
+    #            mirror image fails, the mirror will convert to a
+    #            non-mirrored device if there is only one remaining good
+    #            copy.
+    #
+    # "allocate" - Remove the faulty device and try to allocate space on
+    #            a new device to be a replacement for the failed device.
+    #            Using this policy for the log is fast and maintains the
+    #            ability to remember sync state through crashes/reboots.
+    #            Using this policy for a mirror device is slow, as it
+    #            requires the mirror to resynchronize the devices, but it
+    #            will preserve the mirror characteristic of the device.
+    #            This policy acts like "remove" if no suitable device and
+    #            space can be allocated for the replacement.
+    #
+    # "allocate_anywhere" - Not yet implemented. Useful to place the log device
+    #            temporarily on same physical volume as one of the mirror
+    #            images. This policy is not recommended for mirror devices
+    #            since it would break the redundant nature of the mirror. This
+    #            policy acts like "remove" if no suitable device and space can
+    #            be allocated for the replacement.
+
+    mirror_log_fault_policy = "allocate"
+    mirror_image_fault_policy = "remove"
+
+    # 'snapshot_autoextend_threshold' and 'snapshot_autoextend_percent' define
+    # how to handle automatic snapshot extension. The former defines when the
+    # snapshot should be extended: when its space usage exceeds this many
+    # percent. The latter defines how much extra space should be allocated for
+    # the snapshot, in percent of its current size.
+    #
+    # For example, if you set snapshot_autoextend_threshold to 70 and
+    # snapshot_autoextend_percent to 20, whenever a snapshot exceeds 70% usage,
+    # it will be extended by another 20%. For a 1G snapshot, using up 700M will
+    # trigger a resize to 1.2G. When the usage exceeds 840M, the snapshot will
+    # be extended to 1.44G, and so on.
+    #
+    # Setting snapshot_autoextend_threshold to 100 disables automatic
+    # extensions. The minimum value is 50 (A setting below 50 will be treated
+    # as 50).
+
+    snapshot_autoextend_threshold = 100
+    snapshot_autoextend_percent = 20
+
+    # 'thin_pool_autoextend_threshold' and 'thin_pool_autoextend_percent' define
+    # how to handle automatic pool extension. The former defines when the
+    # pool should be extended: when its space usage exceeds this many
+    # percent. The latter defines how much extra space should be allocated for
+    # the pool, in percent of its current size.
+    #
+    # For example, if you set thin_pool_autoextend_threshold to 70 and
+    # thin_pool_autoextend_percent to 20, whenever a pool exceeds 70% usage,
+    # it will be extended by another 20%. For a 1G pool, using up 700M will
+    # trigger a resize to 1.2G. When the usage exceeds 840M, the pool will
+    # be extended to 1.44G, and so on.
+    #
+    # Setting thin_pool_autoextend_threshold to 100 disables automatic
+    # extensions. The minimum value is 50 (A setting below 50 will be treated
+    # as 50).
+
+    thin_pool_autoextend_threshold = 100
+    thin_pool_autoextend_percent = 20
+
+    # While activating devices, I/O to devices being (re)configured is
+    # suspended, and as a precaution against deadlocks, LVM2 needs to pin
+    # any memory it is using so it is not paged out.  Groups of pages that
+    # are known not to be accessed during activation need not be pinned
+    # into memory.  Each string listed in this setting is compared against
+    # each line in /proc/self/maps, and the pages corresponding to any
+    # lines that match are not pinned.  On some systems locale-archive was
+    # found to make up over 80% of the memory used by the process.
+    # mlock_filter = [ "locale/locale-archive", "gconv/gconv-modules.cache" ]
+
+    # Set to 1 to revert to the default behaviour prior to version 2.02.62
+    # which used mlockall() to pin the whole process's memory while activating
+    # devices.
+    use_mlockall = 0
+
+    # Monitoring is enabled by default when activating logical volumes.
+    # Set to 0 to disable monitoring or use the --ignoremonitoring option.
+    monitoring = 1
+
+    # When pvmove or lvconvert must wait for the kernel to finish
+    # synchronising or merging data, they check and report progress
+    # at intervals of this number of seconds.  The default is 15 seconds.
+    # If this is set to 0 and there is only one thing to wait for, there
+    # are no progress reports, but the process is awoken immediately the
+    # operation is complete.
+    polling_interval = 15
+}
+
+
+####################
+# Advanced section #
+####################
+
+# Metadata settings
+#
+# metadata {
+    # Default number of copies of metadata to hold on each PV.  0, 1 or 2.
+    # You might want to override it from the command line with 0 
+    # when running pvcreate on new PVs which are to be added to large VGs.
+
+    # pvmetadatacopies = 1
+
+    # Default number of copies of metadata to maintain for each VG.
+    # If set to a non-zero value, LVM automatically chooses which of
+    # the available metadata areas to use to achieve the requested
+    # number of copies of the VG metadata.  If you set a value larger
+    # than the the total number of metadata areas available then
+    # metadata is stored in them all.
+    # The default value of 0 ("unmanaged") disables this automatic
+    # management and allows you to control which metadata areas
+    # are used at the individual PV level using 'pvchange
+    # --metadataignore y/n'.
+
+    # vgmetadatacopies = 0
+
+    # Approximate default size of on-disk metadata areas in sectors.
+    # You should increase this if you have large volume groups or
+    # you want to retain a large on-disk history of your metadata changes.
+
+    # pvmetadatasize = 255
+
+    # List of directories holding live copies of text format metadata.
+    # These directories must not be on logical volumes!
+    # It's possible to use LVM2 with a couple of directories here,
+    # preferably on different (non-LV) filesystems, and with no other 
+    # on-disk metadata (pvmetadatacopies = 0). Or this can be in
+    # addition to on-disk metadata areas.
+    # The feature was originally added to simplify testing and is not
+    # supported under low memory situations - the machine could lock up.
+    #
+    # Never edit any files in these directories by hand unless you
+    # you are absolutely sure you know what you are doing! Use
+    # the supplied toolset to make changes (e.g. vgcfgrestore).
+
+    # dirs = [ "/etc/lvm/metadata", "/mnt/disk2/lvm/metadata2" ]
+#}
+
+# Event daemon
+#
+dmeventd {
+    # mirror_library is the library used when monitoring a mirror device.
+    #
+    # "libdevmapper-event-lvm2mirror.so" attempts to recover from
+    # failures.  It removes failed devices from a volume group and
+    # reconfigures a mirror as necessary. If no mirror library is
+    # provided, mirrors are not monitored through dmeventd.
+
+    mirror_library = "libdevmapper-event-lvm2mirror.so"
+
+    # snapshot_library is the library used when monitoring a snapshot device.
+    #
+    # "libdevmapper-event-lvm2snapshot.so" monitors the filling of
+    # snapshots and emits a warning through syslog when the use of
+    # the snapshot exceeds 80%. The warning is repeated when 85%, 90% and
+    # 95% of the snapshot is filled.
+
+    snapshot_library = "libdevmapper-event-lvm2snapshot.so"
+
+    # thin_library is the library used when monitoring a thin device.
+    #
+    # "libdevmapper-event-lvm2thin.so" monitors the filling of
+    # pool and emits a warning through syslog when the use of
+    # the pool exceeds 80%. The warning is repeated when 85%, 90% and
+    # 95% of the pool is filled.
+
+    thin_library = "libdevmapper-event-lvm2thin.so"
+
+    # Full path of the dmeventd binary.
+    #
+    # executable = "@DMEVENTD_PATH@"
+}

doc/example_cmdlib.c

@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2004 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "lvm2cmd.h"
+#include <stdio.h>
+
+/* All output gets passed to this function line-by-line */
+void test_log_fn(int level, const char *file, int line,
+		 int dm_errno, const char *format)
+{
+	/* Extract and process output here rather than printing it */
+
+	if (level != 4)
+		return;
+
+	printf("%s\n", format);
+	return;
+}
+
+int main(int argc, char **argv)
+{
+	void *handle;
+	int r;
+
+	lvm2_log_fn(test_log_fn);
+
+	handle = lvm2_init();
+
+	lvm2_log_level(handle, 1);
+	r = lvm2_run(handle, "vgs --noheadings vg1");
+
+	/* More commands here */
+
+	lvm2_exit(handle);
+
+	return r;
+}
+

doc/kernel/crypt.txt

@@ -0,0 +1,76 @@
+dm-crypt
+=========
+
+Device-Mapper's "crypt" target provides transparent encryption of block devices
+using the kernel crypto API.
+
+Parameters: <cipher> <key> <iv_offset> <device path> \
+	      <offset> [<#opt_params> <opt_params>]
+
+<cipher>
+    Encryption cipher and an optional IV generation mode.
+    (In format cipher[:keycount]-chainmode-ivopts:ivmode).
+    Examples:
+       des
+       aes-cbc-essiv:sha256
+       twofish-ecb
+
+    /proc/crypto contains supported crypto modes
+
+<key>
+    Key used for encryption. It is encoded as a hexadecimal number.
+    You can only use key sizes that are valid for the selected cipher.
+
+<keycount>
+    Multi-key compatibility mode. You can define <keycount> keys and
+    then sectors are encrypted according to their offsets (sector 0 uses key0;
+    sector 1 uses key1 etc.).  <keycount> must be a power of two.
+
+<iv_offset>
+    The IV offset is a sector count that is added to the sector number
+    before creating the IV.
+
+<device path>
+    This is the device that is going to be used as backend and contains the
+    encrypted data.  You can specify it as a path like /dev/xxx or a device
+    number <major>:<minor>.
+
+<offset>
+    Starting sector within the device where the encrypted data begins.
+
+<#opt_params>
+    Number of optional parameters. If there are no optional parameters,
+    the optional paramaters section can be skipped or #opt_params can be zero.
+    Otherwise #opt_params is the number of following arguments.
+
+    Example of optional parameters section:
+        1 allow_discards
+
+allow_discards
+    Block discard requests (a.k.a. TRIM) are passed through the crypt device.
+    The default is to ignore discard requests.
+
+    WARNING: Assess the specific security risks carefully before enabling this
+    option.  For example, allowing discards on encrypted devices may lead to
+    the leak of information about the ciphertext device (filesystem type,
+    used space etc.) if the discarded blocks can be located easily on the
+    device later.
+
+Example scripts
+===============
+LUKS (Linux Unified Key Setup) is now the preferred way to set up disk
+encryption with dm-crypt using the 'cryptsetup' utility, see
+http://code.google.com/p/cryptsetup/
+
+[[
+#!/bin/sh
+# Create a crypt device using dmsetup
+dmsetup create crypt1 --table "0 `blockdev --getsize $1` crypt aes-cbc-essiv:sha256 babebabebabebabebabebabebabebabe 0 $1 0"
+]]
+
+[[
+#!/bin/sh
+# Create a crypt device using cryptsetup and LUKS header with default cipher
+cryptsetup luksFormat $1
+cryptsetup luksOpen $1 crypt1
+]]

doc/kernel/delay.txt

@@ -0,0 +1,26 @@
+dm-delay
+========
+
+Device-Mapper's "delay" target delays reads and/or writes
+and maps them to different devices.
+
+Parameters:
+    <device> <offset> <delay> [<write_device> <write_offset> <write_delay>]
+
+With separate write parameters, the first set is only used for reads.
+Delays are specified in milliseconds.
+
+Example scripts
+===============
+[[
+#!/bin/sh
+# Create device delaying rw operation for 500ms
+echo "0 `blockdev --getsize $1` delay $1 0 500" | dmsetup create delayed
+]]
+
+[[
+#!/bin/sh
+# Create device delaying only write operation for 500ms and
+# splitting reads and writes to different devices $1 $2
+echo "0 `blockdev --getsize $1` delay $1 0 0 $2 0 500" | dmsetup create delayed
+]]

doc/kernel/flakey.txt

@@ -0,0 +1,53 @@
+dm-flakey
+=========
+
+This target is the same as the linear target except that it exhibits
+unreliable behaviour periodically.  It's been found useful in simulating
+failing devices for testing purposes.
+
+Starting from the time the table is loaded, the device is available for
+<up interval> seconds, then exhibits unreliable behaviour for <down
+interval> seconds, and then this cycle repeats.
+
+Also, consider using this in combination with the dm-delay target too,
+which can delay reads and writes and/or send them to different
+underlying devices.
+
+Table parameters
+----------------
+  <dev path> <offset> <up interval> <down interval> \
+    [<num_features> [<feature arguments>]]
+
+Mandatory parameters:
+    <dev path>: Full pathname to the underlying block-device, or a
+                "major:minor" device-number.
+    <offset>: Starting sector within the device.
+    <up interval>: Number of seconds device is available.
+    <down interval>: Number of seconds device returns errors.
+
+Optional feature parameters:
+  If no feature parameters are present, during the periods of
+  unreliability, all I/O returns errors.
+
+  drop_writes:
+	All write I/O is silently ignored.
+	Read I/O is handled correctly.
+
+  corrupt_bio_byte <Nth_byte> <direction> <value> <flags>:
+	During <down interval>, replace <Nth_byte> of the data of
+	each matching bio with <value>.
+
+    <Nth_byte>: The offset of the byte to replace.
+		Counting starts at 1, to replace the first byte.
+    <direction>: Either 'r' to corrupt reads or 'w' to corrupt writes.
+		 'w' is incompatible with drop_writes.
+    <value>: The value (from 0-255) to write.
+    <flags>: Perform the replacement only if bio->bi_rw has all the
+	     selected flags set.
+
+Examples:
+  corrupt_bio_byte 32 r 1 0
+	- replaces the 32nd byte of READ bios with the value 1
+
+  corrupt_bio_byte 224 w 0 32
+	- replaces the 224th byte of REQ_META (=32) bios with the value 0

doc/kernel/io.txt

@@ -0,0 +1,75 @@
+dm-io
+=====
+
+Dm-io provides synchronous and asynchronous I/O services. There are three
+types of I/O services available, and each type has a sync and an async
+version.
+
+The user must set up an io_region structure to describe the desired location
+of the I/O. Each io_region indicates a block-device along with the starting
+sector and size of the region.
+
+   struct io_region {
+      struct block_device *bdev;
+      sector_t sector;
+      sector_t count;
+   };
+
+Dm-io can read from one io_region or write to one or more io_regions. Writes
+to multiple regions are specified by an array of io_region structures.
+
+The first I/O service type takes a list of memory pages as the data buffer for
+the I/O, along with an offset into the first page.
+
+   struct page_list {
+      struct page_list *next;
+      struct page *page;
+   };
+
+   int dm_io_sync(unsigned int num_regions, struct io_region *where, int rw,
+                  struct page_list *pl, unsigned int offset,
+                  unsigned long *error_bits);
+   int dm_io_async(unsigned int num_regions, struct io_region *where, int rw,
+                   struct page_list *pl, unsigned int offset,
+                   io_notify_fn fn, void *context);
+
+The second I/O service type takes an array of bio vectors as the data buffer
+for the I/O. This service can be handy if the caller has a pre-assembled bio,
+but wants to direct different portions of the bio to different devices.
+
+   int dm_io_sync_bvec(unsigned int num_regions, struct io_region *where,
+                       int rw, struct bio_vec *bvec,
+                       unsigned long *error_bits);
+   int dm_io_async_bvec(unsigned int num_regions, struct io_region *where,
+                        int rw, struct bio_vec *bvec,
+                        io_notify_fn fn, void *context);
+
+The third I/O service type takes a pointer to a vmalloc'd memory buffer as the
+data buffer for the I/O. This service can be handy if the caller needs to do
+I/O to a large region but doesn't want to allocate a large number of individual
+memory pages.
+
+   int dm_io_sync_vm(unsigned int num_regions, struct io_region *where, int rw,
+                     void *data, unsigned long *error_bits);
+   int dm_io_async_vm(unsigned int num_regions, struct io_region *where, int rw,
+                      void *data, io_notify_fn fn, void *context);
+
+Callers of the asynchronous I/O services must include the name of a completion
+callback routine and a pointer to some context data for the I/O.
+
+   typedef void (*io_notify_fn)(unsigned long error, void *context);
+
+The "error" parameter in this callback, as well as the "*error" parameter in
+all of the synchronous versions, is a bitset (instead of a simple error value).
+In the case of an write-I/O to multiple regions, this bitset allows dm-io to
+indicate success or failure on each individual region.
+
+Before using any of the dm-io services, the user should call dm_io_get()
+and specify the number of pages they expect to perform I/O on concurrently.
+Dm-io will attempt to resize its mempool to make sure enough pages are
+always available in order to avoid unnecessary waiting while performing I/O.
+
+When the user is finished using the dm-io services, they should call
+dm_io_put() and specify the same number of pages that were given on the
+dm_io_get() call.
+

doc/kernel/kcopyd.txt

@@ -0,0 +1,47 @@
+kcopyd
+======
+
+Kcopyd provides the ability to copy a range of sectors from one block-device
+to one or more other block-devices, with an asynchronous completion
+notification. It is used by dm-snapshot and dm-mirror.
+
+Users of kcopyd must first create a client and indicate how many memory pages
+to set aside for their copy jobs. This is done with a call to
+kcopyd_client_create().
+
+   int kcopyd_client_create(unsigned int num_pages,
+                            struct kcopyd_client **result);
+
+To start a copy job, the user must set up io_region structures to describe
+the source and destinations of the copy. Each io_region indicates a
+block-device along with the starting sector and size of the region. The source
+of the copy is given as one io_region structure, and the destinations of the
+copy are given as an array of io_region structures.
+
+   struct io_region {
+      struct block_device *bdev;
+      sector_t sector;
+      sector_t count;
+   };
+
+To start the copy, the user calls kcopyd_copy(), passing in the client
+pointer, pointers to the source and destination io_regions, the name of a
+completion callback routine, and a pointer to some context data for the copy.
+
+   int kcopyd_copy(struct kcopyd_client *kc, struct io_region *from,
+                   unsigned int num_dests, struct io_region *dests,
+                   unsigned int flags, kcopyd_notify_fn fn, void *context);
+
+   typedef void (*kcopyd_notify_fn)(int read_err, unsigned int write_err,
+				    void *context);
+
+When the copy completes, kcopyd will call the user's completion routine,
+passing back the user's context pointer. It will also indicate if a read or
+write error occurred during the copy.
+
+When a user is done with all their copy jobs, they should call
+kcopyd_client_destroy() to delete the kcopyd client, which will release the
+associated memory pages.
+
+   void kcopyd_client_destroy(struct kcopyd_client *kc);
+

doc/kernel/linear.txt

@@ -0,0 +1,61 @@
+dm-linear
+=========
+
+Device-Mapper's "linear" target maps a linear range of the Device-Mapper
+device onto a linear range of another device.  This is the basic building
+block of logical volume managers.
+
+Parameters: <dev path> <offset>
+    <dev path>: Full pathname to the underlying block-device, or a
+                "major:minor" device-number.
+    <offset>: Starting sector within the device.
+
+
+Example scripts
+===============
+[[
+#!/bin/sh
+# Create an identity mapping for a device
+echo "0 `blockdev --getsize $1` linear $1 0" | dmsetup create identity
+]]
+
+
+[[
+#!/bin/sh
+# Join 2 devices together
+size1=`blockdev --getsize $1`
+size2=`blockdev --getsize $2`
+echo "0 $size1 linear $1 0
+$size1 $size2 linear $2 0" | dmsetup create joined
+]]
+
+
+[[
+#!/usr/bin/perl -w
+# Split a device into 4M chunks and then join them together in reverse order.
+
+my $name = "reverse";
+my $extent_size = 4 * 1024 * 2;
+my $dev = $ARGV[0];
+my $table = "";
+my $count = 0;
+
+if (!defined($dev)) {
+        die("Please specify a device.\n");
+}
+
+my $dev_size = `blockdev --getsize $dev`;
+my $extents = int($dev_size / $extent_size) -
+              (($dev_size % $extent_size) ? 1 : 0);
+
+while ($extents > 0) {
+        my $this_start = $count * $extent_size;
+        $extents--;
+        $count++;
+        my $this_offset = $extents * $extent_size;
+
+        $table .= "$this_start $extent_size linear $dev $this_offset\n";
+}
+
+`echo \"$table\" | dmsetup create $name`;
+]]

doc/kernel/log.txt

@@ -0,0 +1,54 @@
+Device-Mapper Logging
+=====================
+The device-mapper logging code is used by some of the device-mapper
+RAID targets to track regions of the disk that are not consistent.
+A region (or portion of the address space) of the disk may be
+inconsistent because a RAID stripe is currently being operated on or
+a machine died while the region was being altered.  In the case of
+mirrors, a region would be considered dirty/inconsistent while you
+are writing to it because the writes need to be replicated for all
+the legs of the mirror and may not reach the legs at the same time.
+Once all writes are complete, the region is considered clean again.
+
+There is a generic logging interface that the device-mapper RAID
+implementations use to perform logging operations (see
+dm_dirty_log_type in include/linux/dm-dirty-log.h).  Various different
+logging implementations are available and provide different
+capabilities.  The list includes:
+
+Type		Files
+====		=====
+disk		drivers/md/dm-log.c
+core		drivers/md/dm-log.c
+userspace	drivers/md/dm-log-userspace* include/linux/dm-log-userspace.h
+
+The "disk" log type
+-------------------
+This log implementation commits the log state to disk.  This way, the
+logging state survives reboots/crashes.
+
+The "core" log type
+-------------------
+This log implementation keeps the log state in memory.  The log state
+will not survive a reboot or crash, but there may be a small boost in
+performance.  This method can also be used if no storage device is
+available for storing log state.
+
+The "userspace" log type
+------------------------
+This log type simply provides a way to export the log API to userspace,
+so log implementations can be done there.  This is done by forwarding most
+logging requests to userspace, where a daemon receives and processes the
+request.
+
+The structure used for communication between kernel and userspace are
+located in include/linux/dm-log-userspace.h.  Due to the frequency,
+diversity, and 2-way communication nature of the exchanges between
+kernel and userspace, 'connector' is used as the interface for
+communication.
+
+There are currently two userspace log implementations that leverage this
+framework - "clustered-disk" and "clustered-core".  These implementations
+provide a cluster-coherent log for shared-storage.  Device-mapper mirroring
+can be used in a shared-storage environment when the cluster log implementations
+are employed.

doc/kernel/persistent-data.txt

@@ -0,0 +1,84 @@
+Introduction
+============
+
+The more-sophisticated device-mapper targets require complex metadata
+that is managed in kernel.  In late 2010 we were seeing that various
+different targets were rolling their own data strutures, for example:
+
+- Mikulas Patocka's multisnap implementation
+- Heinz Mauelshagen's thin provisioning target
+- Another btree-based caching target posted to dm-devel
+- Another multi-snapshot target based on a design of Daniel Phillips
+
+Maintaining these data structures takes a lot of work, so if possible
+we'd like to reduce the number.
+
+The persistent-data library is an attempt to provide a re-usable
+framework for people who want to store metadata in device-mapper
+targets.  It's currently used by the thin-provisioning target and an
+upcoming hierarchical storage target.
+
+Overview
+========
+
+The main documentation is in the header files which can all be found
+under drivers/md/persistent-data.
+
+The block manager
+-----------------
+
+dm-block-manager.[hc]
+
+This provides access to the data on disk in fixed sized-blocks.  There
+is a read/write locking interface to prevent concurrent accesses, and
+keep data that is being used in the cache.
+
+Clients of persistent-data are unlikely to use this directly.
+
+The transaction manager
+-----------------------
+
+dm-transaction-manager.[hc]
+
+This restricts access to blocks and enforces copy-on-write semantics.
+The only way you can get hold of a writable block through the
+transaction manager is by shadowing an existing block (ie. doing
+copy-on-write) or allocating a fresh one.  Shadowing is elided within
+the same transaction so performance is reasonable.  The commit method
+ensures that all data is flushed before it writes the superblock.
+On power failure your metadata will be as it was when last committed.
+
+The Space Maps
+--------------
+
+dm-space-map.h
+dm-space-map-metadata.[hc]
+dm-space-map-disk.[hc]
+
+On-disk data structures that keep track of reference counts of blocks.
+Also acts as the allocator of new blocks.  Currently two
+implementations: a simpler one for managing blocks on a different
+device (eg. thinly-provisioned data blocks); and one for managing
+the metadata space.  The latter is complicated by the need to store
+its own data within the space it's managing.
+
+The data structures
+-------------------
+
+dm-btree.[hc]
+dm-btree-remove.c
+dm-btree-spine.c
+dm-btree-internal.h
+
+Currently there is only one data structure, a hierarchical btree.
+There are plans to add more.  For example, something with an
+array-like interface would see a lot of use.
+
+The btree is 'hierarchical' in that you can define it to be composed
+of nested btrees, and take multiple keys.  For example, the
+thin-provisioning target uses a btree with two levels of nesting.
+The first maps a device id to a mapping tree, and that in turn maps a
+virtual block to a physical block.
+
+Values stored in the btrees can have arbitrary size.  Keys are always
+64bits, although nesting allows you to use multiple keys.

doc/kernel/queue-length.txt

@@ -0,0 +1,39 @@
+dm-queue-length
+===============
+
+dm-queue-length is a path selector module for device-mapper targets,
+which selects a path with the least number of in-flight I/Os.
+The path selector name is 'queue-length'.
+
+Table parameters for each path: [<repeat_count>]
+	<repeat_count>: The number of I/Os to dispatch using the selected
+			path before switching to the next path.
+			If not given, internal default is used. To check
+			the default value, see the activated table.
+
+Status for each path: <status> <fail-count> <in-flight>
+	<status>: 'A' if the path is active, 'F' if the path is failed.
+	<fail-count>: The number of path failures.
+	<in-flight>: The number of in-flight I/Os on the path.
+
+
+Algorithm
+=========
+
+dm-queue-length increments/decrements 'in-flight' when an I/O is
+dispatched/completed respectively.
+dm-queue-length selects a path with the minimum 'in-flight'.
+
+
+Examples
+========
+In case that 2 paths (sda and sdb) are used with repeat_count == 128.
+
+# echo "0 10 multipath 0 0 1 1 queue-length 0 2 1 8:0 128 8:16 128" \
+  dmsetup create test
+#
+# dmsetup table
+test: 0 10 multipath 0 0 1 1 queue-length 0 2 1 8:0 128 8:16 128
+#
+# dmsetup status
+test: 0 10 multipath 2 0 0 0 1 1 E 0 2 1 8:0 A 0 0 8:16 A 0 0

doc/kernel/raid.txt

@@ -0,0 +1,108 @@
+dm-raid
+-------
+
+The device-mapper RAID (dm-raid) target provides a bridge from DM to MD.
+It allows the MD RAID drivers to be accessed using a device-mapper
+interface.
+
+The target is named "raid" and it accepts the following parameters:
+
+  <raid_type> <#raid_params> <raid_params> \
+    <#raid_devs> <metadata_dev0> <dev0> [.. <metadata_devN> <devN>]
+
+<raid_type>:
+  raid1		RAID1 mirroring
+  raid4		RAID4 dedicated parity disk
+  raid5_la	RAID5 left asymmetric
+		- rotating parity 0 with data continuation
+  raid5_ra	RAID5 right asymmetric
+		- rotating parity N with data continuation
+  raid5_ls	RAID5 left symmetric
+		- rotating parity 0 with data restart
+  raid5_rs 	RAID5 right symmetric
+		- rotating parity N with data restart
+  raid6_zr	RAID6 zero restart
+		- rotating parity zero (left-to-right) with data restart
+  raid6_nr	RAID6 N restart
+		- rotating parity N (right-to-left) with data restart
+  raid6_nc	RAID6 N continue
+		- rotating parity N (right-to-left) with data continuation
+
+  Refererence: Chapter 4 of
+  http://www.snia.org/sites/default/files/SNIA_DDF_Technical_Position_v2.0.pdf
+
+<#raid_params>: The number of parameters that follow.
+
+<raid_params> consists of
+    Mandatory parameters:
+        <chunk_size>: Chunk size in sectors.  This parameter is often known as
+		      "stripe size".  It is the only mandatory parameter and
+		      is placed first.
+
+    followed by optional parameters (in any order):
+	[sync|nosync]   Force or prevent RAID initialization.
+
+	[rebuild <idx>]	Rebuild drive number idx (first drive is 0).
+
+	[daemon_sleep <ms>]
+		Interval between runs of the bitmap daemon that
+		clear bits.  A longer interval means less bitmap I/O but
+		resyncing after a failure is likely to take longer.
+
+	[min_recovery_rate <kB/sec/disk>]  Throttle RAID initialization
+	[max_recovery_rate <kB/sec/disk>]  Throttle RAID initialization
+	[write_mostly <idx>]		   Drive index is write-mostly
+	[max_write_behind <sectors>]       See '-write-behind=' (man mdadm)
+	[stripe_cache <sectors>]           Stripe cache size (higher RAIDs only)
+	[region_size <sectors>]
+		The region_size multiplied by the number of regions is the
+		logical size of the array.  The bitmap records the device
+		synchronisation state for each region.
+
+<#raid_devs>: The number of devices composing the array.
+	Each device consists of two entries.  The first is the device
+	containing the metadata (if any); the second is the one containing the
+	data.
+
+	If a drive has failed or is missing at creation time, a '-' can be
+	given for both the metadata and data drives for a given position.
+
+
+Example tables
+--------------
+# RAID4 - 4 data drives, 1 parity (no metadata devices)
+# No metadata devices specified to hold superblock/bitmap info
+# Chunk size of 1MiB
+# (Lines separated for easy reading)
+
+0 1960893648 raid \
+        raid4 1 2048 \
+        5 - 8:17 - 8:33 - 8:49 - 8:65 - 8:81
+
+# RAID4 - 4 data drives, 1 parity (with metadata devices)
+# Chunk size of 1MiB, force RAID initialization,
+#       min recovery rate at 20 kiB/sec/disk
+
+0 1960893648 raid \
+        raid4 4 2048 sync min_recovery_rate 20 \
+        5 8:17 8:18 8:33 8:34 8:49 8:50 8:65 8:66 8:81 8:82
+
+'dmsetup table' displays the table used to construct the mapping.
+The optional parameters are always printed in the order listed
+above with "sync" or "nosync" always output ahead of the other
+arguments, regardless of the order used when originally loading the table.
+Arguments that can be repeated are ordered by value.
+
+'dmsetup status' yields information on the state and health of the
+array.
+The output is as follows:
+1: <s> <l> raid \
+2:      <raid_type> <#devices> <1 health char for each dev> <resync_ratio>
+
+Line 1 is the standard output produced by device-mapper.
+Line 2 is produced by the raid target, and best explained by example:
+        0 1960893648 raid raid4 5 AAAAA 2/490221568
+Here we can see the RAID type is raid4, there are 5 devices - all of
+which are 'A'live, and the array is 2/490221568 complete with recovery.
+Faulty or missing devices are marked 'D'.  Devices that are out-of-sync
+are marked 'a'.

doc/kernel/service-time.txt

@@ -0,0 +1,91 @@
+dm-service-time
+===============
+
+dm-service-time is a path selector module for device-mapper targets,
+which selects a path with the shortest estimated service time for
+the incoming I/O.
+
+The service time for each path is estimated by dividing the total size
+of in-flight I/Os on a path with the performance value of the path.
+The performance value is a relative throughput value among all paths
+in a path-group, and it can be specified as a table argument.
+
+The path selector name is 'service-time'.
+
+Table parameters for each path: [<repeat_count> [<relative_throughput>]]
+	<repeat_count>: The number of I/Os to dispatch using the selected
+			path before switching to the next path.
+			If not given, internal default is used.  To check
+			the default value, see the activated table.
+	<relative_throughput>: The relative throughput value of the path
+			among all paths in the path-group.
+			The valid range is 0-100.
+			If not given, minimum value '1' is used.
+			If '0' is given, the path isn't selected while
+			other paths having a positive value are available.
+
+Status for each path: <status> <fail-count> <in-flight-size> \
+		      <relative_throughput>
+	<status>: 'A' if the path is active, 'F' if the path is failed.
+	<fail-count>: The number of path failures.
+	<in-flight-size>: The size of in-flight I/Os on the path.
+	<relative_throughput>: The relative throughput value of the path
+			among all paths in the path-group.
+
+
+Algorithm
+=========
+
+dm-service-time adds the I/O size to 'in-flight-size' when the I/O is
+dispatched and subtracts when completed.
+Basically, dm-service-time selects a path having minimum service time
+which is calculated by:
+
+	('in-flight-size' + 'size-of-incoming-io') / 'relative_throughput'
+
+However, some optimizations below are used to reduce the calculation
+as much as possible.
+
+	1. If the paths have the same 'relative_throughput', skip
+	   the division and just compare the 'in-flight-size'.
+
+	2. If the paths have the same 'in-flight-size', skip the division
+	   and just compare the 'relative_throughput'.
+
+	3. If some paths have non-zero 'relative_throughput' and others
+	   have zero 'relative_throughput', ignore those paths with zero
+	   'relative_throughput'.
+
+If such optimizations can't be applied, calculate service time, and
+compare service time.
+If calculated service time is equal, the path having maximum
+'relative_throughput' may be better.  So compare 'relative_throughput'
+then.
+
+
+Examples
+========
+In case that 2 paths (sda and sdb) are used with repeat_count == 128
+and sda has an average throughput 1GB/s and sdb has 4GB/s,
+'relative_throughput' value may be '1' for sda and '4' for sdb.
+
+# echo "0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 1 8:16 128 4" \
+  dmsetup create test
+#
+# dmsetup table
+test: 0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 1 8:16 128 4
+#
+# dmsetup status
+test: 0 10 multipath 2 0 0 0 1 1 E 0 2 2 8:0 A 0 0 1 8:16 A 0 0 4
+
+
+Or '2' for sda and '8' for sdb would be also true.
+
+# echo "0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 2 8:16 128 8" \
+  dmsetup create test
+#
+# dmsetup table
+test: 0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 2 8:16 128 8
+#
+# dmsetup status
+test: 0 10 multipath 2 0 0 0 1 1 E 0 2 2 8:0 A 0 0 2 8:16 A 0 0 8

doc/kernel/snapshot.txt

@@ -0,0 +1,168 @@
+Device-mapper snapshot support
+==============================
+
+Device-mapper allows you, without massive data copying:
+
+*) To create snapshots of any block device i.e. mountable, saved states of
+the block device which are also writable without interfering with the
+original content;
+*) To create device "forks", i.e. multiple different versions of the
+same data stream.
+*) To merge a snapshot of a block device back into the snapshot's origin
+device.
+
+In the first two cases, dm copies only the chunks of data that get
+changed and uses a separate copy-on-write (COW) block device for
+storage.
+
+For snapshot merge the contents of the COW storage are merged back into
+the origin device.
+
+
+There are three dm targets available:
+snapshot, snapshot-origin, and snapshot-merge.
+
+*) snapshot-origin <origin>
+
+which will normally have one or more snapshots based on it.
+Reads will be mapped directly to the backing device. For each write, the
+original data will be saved in the <COW device> of each snapshot to keep
+its visible content unchanged, at least until the <COW device> fills up.
+
+
+*) snapshot <origin> <COW device> <persistent?> <chunksize>
+
+A snapshot of the <origin> block device is created. Changed chunks of
+<chunksize> sectors will be stored on the <COW device>.  Writes will
+only go to the <COW device>.  Reads will come from the <COW device> or
+from <origin> for unchanged data.  <COW device> will often be
+smaller than the origin and if it fills up the snapshot will become
+useless and be disabled, returning errors.  So it is important to monitor
+the amount of free space and expand the <COW device> before it fills up.
+
+<persistent?> is P (Persistent) or N (Not persistent - will not survive
+after reboot).
+The difference is that for transient snapshots less metadata must be
+saved on disk - they can be kept in memory by the kernel.
+
+
+* snapshot-merge <origin> <COW device> <persistent> <chunksize>
+
+takes the same table arguments as the snapshot target except it only
+works with persistent snapshots.  This target assumes the role of the
+"snapshot-origin" target and must not be loaded if the "snapshot-origin"
+is still present for <origin>.
+
+Creates a merging snapshot that takes control of the changed chunks
+stored in the <COW device> of an existing snapshot, through a handover
+procedure, and merges these chunks back into the <origin>.  Once merging
+has started (in the background) the <origin> may be opened and the merge
+will continue while I/O is flowing to it.  Changes to the <origin> are
+deferred until the merging snapshot's corresponding chunk(s) have been
+merged.  Once merging has started the snapshot device, associated with
+the "snapshot" target, will return -EIO when accessed.
+
+
+How snapshot is used by LVM2
+============================
+When you create the first LVM2 snapshot of a volume, four dm devices are used:
+
+1) a device containing the original mapping table of the source volume;
+2) a device used as the <COW device>;
+3) a "snapshot" device, combining #1 and #2, which is the visible snapshot
+   volume;
+4) the "original" volume (which uses the device number used by the original
+   source volume), whose table is replaced by a "snapshot-origin" mapping
+   from device #1.
+
+A fixed naming scheme is used, so with the following commands:
+
+lvcreate -L 1G -n base volumeGroup
+lvcreate -L 100M --snapshot -n snap volumeGroup/base
+
+we'll have this situation (with volumes in above order):
+
+# dmsetup table|grep volumeGroup
+
+volumeGroup-base-real: 0 2097152 linear 8:19 384
+volumeGroup-snap-cow: 0 204800 linear 8:19 2097536
+volumeGroup-snap: 0 2097152 snapshot 254:11 254:12 P 16
+volumeGroup-base: 0 2097152 snapshot-origin 254:11
+
+# ls -lL /dev/mapper/volumeGroup-*
+brw-------  1 root root 254, 11 29 ago 18:15 /dev/mapper/volumeGroup-base-real
+brw-------  1 root root 254, 12 29 ago 18:15 /dev/mapper/volumeGroup-snap-cow
+brw-------  1 root root 254, 13 29 ago 18:15 /dev/mapper/volumeGroup-snap
+brw-------  1 root root 254, 10 29 ago 18:14 /dev/mapper/volumeGroup-base
+
+
+How snapshot-merge is used by LVM2
+==================================
+A merging snapshot assumes the role of the "snapshot-origin" while
+merging.  As such the "snapshot-origin" is replaced with
+"snapshot-merge".  The "-real" device is not changed and the "-cow"
+device is renamed to <origin name>-cow to aid LVM2's cleanup of the
+merging snapshot after it completes.  The "snapshot" that hands over its
+COW device to the "snapshot-merge" is deactivated (unless using lvchange
+--refresh); but if it is left active it will simply return I/O errors.
+
+A snapshot will merge into its origin with the following command:
+
+lvconvert --merge volumeGroup/snap
+
+we'll now have this situation:
+
+# dmsetup table|grep volumeGroup
+
+volumeGroup-base-real: 0 2097152 linear 8:19 384
+volumeGroup-base-cow: 0 204800 linear 8:19 2097536
+volumeGroup-base: 0 2097152 snapshot-merge 254:11 254:12 P 16
+
+# ls -lL /dev/mapper/volumeGroup-*
+brw-------  1 root root 254, 11 29 ago 18:15 /dev/mapper/volumeGroup-base-real
+brw-------  1 root root 254, 12 29 ago 18:16 /dev/mapper/volumeGroup-base-cow
+brw-------  1 root root 254, 10 29 ago 18:16 /dev/mapper/volumeGroup-base
+
+
+How to determine when a merging is complete
+===========================================
+The snapshot-merge and snapshot status lines end with:
+  <sectors_allocated>/<total_sectors> <metadata_sectors>
+
+Both <sectors_allocated> and <total_sectors> include both data and metadata.
+During merging, the number of sectors allocated gets smaller and
+smaller.  Merging has finished when the number of sectors holding data
+is zero, in other words <sectors_allocated> == <metadata_sectors>.
+
+Here is a practical example (using a hybrid of lvm and dmsetup commands):
+
+# lvs
+  LV      VG          Attr   LSize Origin  Snap%  Move Log Copy%  Convert
+  base    volumeGroup owi-a- 4.00g
+  snap    volumeGroup swi-a- 1.00g base  18.97
+
+# dmsetup status volumeGroup-snap
+0 8388608 snapshot 397896/2097152 1560
+                                  ^^^^ metadata sectors
+
+# lvconvert --merge -b volumeGroup/snap
+  Merging of volume snap started.
+
+# lvs volumeGroup/snap
+  LV      VG          Attr   LSize Origin  Snap%  Move Log Copy%  Convert
+  base    volumeGroup Owi-a- 4.00g          17.23
+
+# dmsetup status volumeGroup-base
+0 8388608 snapshot-merge 281688/2097152 1104
+
+# dmsetup status volumeGroup-base
+0 8388608 snapshot-merge 180480/2097152 712
+
+# dmsetup status volumeGroup-base
+0 8388608 snapshot-merge 16/2097152 16
+
+Merging has finished.
+
+# lvs
+  LV      VG          Attr   LSize Origin  Snap%  Move Log Copy%  Convert
+  base    volumeGroup owi-a- 4.00g

doc/kernel/striped.txt

@@ -0,0 +1,58 @@
+dm-stripe
+=========
+
+Device-Mapper's "striped" target is used to create a striped (i.e. RAID-0)
+device across one or more underlying devices. Data is written in "chunks",
+with consecutive chunks rotating among the underlying devices. This can
+potentially provide improved I/O throughput by utilizing several physical
+devices in parallel.
+
+Parameters: <num devs> <chunk size> [<dev path> <offset>]+
+    <num devs>: Number of underlying devices.
+    <chunk size>: Size of each chunk of data. Must be a power-of-2 and at
+                  least as large as the system's PAGE_SIZE.
+    <dev path>: Full pathname to the underlying block-device, or a
+                "major:minor" device-number.
+    <offset>: Starting sector within the device.
+
+One or more underlying devices can be specified. The striped device size must
+be a multiple of the chunk size and a multiple of the number of underlying
+devices.
+
+
+Example scripts
+===============
+
+[[
+#!/usr/bin/perl -w
+# Create a striped device across any number of underlying devices. The device
+# will be called "stripe_dev" and have a chunk-size of 128k.
+
+my $chunk_size = 128 * 2;
+my $dev_name = "stripe_dev";
+my $num_devs = @ARGV;
+my @devs = @ARGV;
+my ($min_dev_size, $stripe_dev_size, $i);
+
+if (!$num_devs) {
+        die("Specify at least one device\n");
+}
+
+$min_dev_size = `blockdev --getsize $devs[0]`;
+for ($i = 1; $i < $num_devs; $i++) {
+        my $this_size = `blockdev --getsize $devs[$i]`;
+        $min_dev_size = ($min_dev_size < $this_size) ?
+                        $min_dev_size : $this_size;
+}
+
+$stripe_dev_size = $min_dev_size * $num_devs;
+$stripe_dev_size -= $stripe_dev_size % ($chunk_size * $num_devs);
+
+$table = "0 $stripe_dev_size striped $num_devs $chunk_size";
+for ($i = 0; $i < $num_devs; $i++) {
+        $table .= " $devs[$i] 0";
+}
+
+`echo $table | dmsetup create $dev_name`;
+]]
+

doc/kernel/thin-provisioning.txt

@@ -0,0 +1,285 @@
+Introduction
+============
+
+This document descibes a collection of device-mapper targets that
+between them implement thin-provisioning and snapshots.
+
+The main highlight of this implementation, compared to the previous
+implementation of snapshots, is that it allows many virtual devices to
+be stored on the same data volume.  This simplifies administration and
+allows the sharing of data between volumes, thus reducing disk usage.
+
+Another significant feature is support for an arbitrary depth of
+recursive snapshots (snapshots of snapshots of snapshots ...).  The
+previous implementation of snapshots did this by chaining together
+lookup tables, and so performance was O(depth).  This new
+implementation uses a single data structure to avoid this degradation
+with depth.  Fragmentation may still be an issue, however, in some
+scenarios.
+
+Metadata is stored on a separate device from data, giving the
+administrator some freedom, for example to:
+
+- Improve metadata resilience by storing metadata on a mirrored volume
+  but data on a non-mirrored one.
+
+- Improve performance by storing the metadata on SSD.
+
+Status
+======
+
+These targets are very much still in the EXPERIMENTAL state.  Please
+do not yet rely on them in production.  But do experiment and offer us
+feedback.  Different use cases will have different performance
+characteristics, for example due to fragmentation of the data volume.
+
+If you find this software is not performing as expected please mail
+dm-devel@redhat.com with details and we'll try our best to improve
+things for you.
+
+Userspace tools for checking and repairing the metadata are under
+development.
+
+Cookbook
+========
+
+This section describes some quick recipes for using thin provisioning.
+They use the dmsetup program to control the device-mapper driver
+directly.  End users will be advised to use a higher-level volume
+manager such as LVM2 once support has been added.
+
+Pool device
+-----------
+
+The pool device ties together the metadata volume and the data volume.
+It maps I/O linearly to the data volume and updates the metadata via
+two mechanisms:
+
+- Function calls from the thin targets
+
+- Device-mapper 'messages' from userspace which control the creation of new
+  virtual devices amongst other things.
+
+Setting up a fresh pool device
+------------------------------
+
+Setting up a pool device requires a valid metadata device, and a
+data device.  If you do not have an existing metadata device you can
+make one by zeroing the first 4k to indicate empty metadata.
+
+    dd if=/dev/zero of=$metadata_dev bs=4096 count=1
+
+The amount of metadata you need will vary according to how many blocks
+are shared between thin devices (i.e. through snapshots).  If you have
+less sharing than average you'll need a larger-than-average metadata device.
+
+As a guide, we suggest you calculate the number of bytes to use in the
+metadata device as 48 * $data_dev_size / $data_block_size but round it up
+to 2MB if the answer is smaller.  The largest size supported is 16GB.
+
+If you're creating large numbers of snapshots which are recording large
+amounts of change, you may need find you need to increase this.
+
+Reloading a pool table
+----------------------
+
+You may reload a pool's table, indeed this is how the pool is resized
+if it runs out of space.  (N.B. While specifying a different metadata
+device when reloading is not forbidden at the moment, things will go
+wrong if it does not route I/O to exactly the same on-disk location as
+previously.)
+
+Using an existing pool device
+-----------------------------
+
+    dmsetup create pool \
+	--table "0 20971520 thin-pool $metadata_dev $data_dev \
+		 $data_block_size $low_water_mark"
+
+$data_block_size gives the smallest unit of disk space that can be
+allocated at a time expressed in units of 512-byte sectors.  People
+primarily interested in thin provisioning may want to use a value such
+as 1024 (512KB).  People doing lots of snapshotting may want a smaller value
+such as 128 (64KB).  If you are not zeroing newly-allocated data,
+a larger $data_block_size in the region of 256000 (128MB) is suggested.
+$data_block_size must be the same for the lifetime of the
+metadata device.
+
+$low_water_mark is expressed in blocks of size $data_block_size.  If
+free space on the data device drops below this level then a dm event
+will be triggered which a userspace daemon should catch allowing it to
+extend the pool device.  Only one such event will be sent.
+Resuming a device with a new table itself triggers an event so the
+userspace daemon can use this to detect a situation where a new table
+already exceeds the threshold.
+
+Thin provisioning
+-----------------
+
+i) Creating a new thinly-provisioned volume.
+
+  To create a new thinly- provisioned volume you must send a message to an
+  active pool device, /dev/mapper/pool in this example.
+
+    dmsetup message /dev/mapper/pool 0 "create_thin 0"
+
+  Here '0' is an identifier for the volume, a 24-bit number.  It's up
+  to the caller to allocate and manage these identifiers.  If the
+  identifier is already in use, the message will fail with -EEXIST.
+
+ii) Using a thinly-provisioned volume.
+
+  Thinly-provisioned volumes are activated using the 'thin' target:
+
+    dmsetup create thin --table "0 2097152 thin /dev/mapper/pool 0"
+
+  The last parameter is the identifier for the thinp device.
+
+Internal snapshots
+------------------
+
+i) Creating an internal snapshot.
+
+  Snapshots are created with another message to the pool.
+
+  N.B.  If the origin device that you wish to snapshot is active, you
+  must suspend it before creating the snapshot to avoid corruption.
+  This is NOT enforced at the moment, so please be careful!
+
+    dmsetup suspend /dev/mapper/thin
+    dmsetup message /dev/mapper/pool 0 "create_snap 1 0"
+    dmsetup resume /dev/mapper/thin
+
+  Here '1' is the identifier for the volume, a 24-bit number.  '0' is the
+  identifier for the origin device.
+
+ii) Using an internal snapshot.
+
+  Once created, the user doesn't have to worry about any connection
+  between the origin and the snapshot.  Indeed the snapshot is no
+  different from any other thinly-provisioned device and can be
+  snapshotted itself via the same method.  It's perfectly legal to
+  have only one of them active, and there's no ordering requirement on
+  activating or removing them both.  (This differs from conventional
+  device-mapper snapshots.)
+
+  Activate it exactly the same way as any other thinly-provisioned volume:
+
+    dmsetup create snap --table "0 2097152 thin /dev/mapper/pool 1"
+
+Deactivation
+------------
+
+All devices using a pool must be deactivated before the pool itself
+can be.
+
+    dmsetup remove thin
+    dmsetup remove snap
+    dmsetup remove pool
+
+Reference
+=========
+
+'thin-pool' target
+------------------
+
+i) Constructor
+
+    thin-pool <metadata dev> <data dev> <data block size (sectors)> \
+	      <low water mark (blocks)> [<number of feature args> [<arg>]*]
+
+    Optional feature arguments:
+    - 'skip_block_zeroing': skips the zeroing of newly-provisioned blocks.
+
+    Data block size must be between 64KB (128 sectors) and 1GB
+    (2097152 sectors) inclusive.
+
+
+ii) Status
+
+    <transaction id> <used metadata blocks>/<total metadata blocks>
+    <used data blocks>/<total data blocks> <held metadata root>
+
+
+    transaction id:
+	A 64-bit number used by userspace to help synchronise with metadata
+	from volume managers.
+
+    used data blocks / total data blocks
+	If the number of free blocks drops below the pool's low water mark a
+	dm event will be sent to userspace.  This event is edge-triggered and
+	it will occur only once after each resume so volume manager writers
+	should register for the event and then check the target's status.
+
+    held metadata root:
+	The location, in sectors, of the metadata root that has been
+	'held' for userspace read access.  '-' indicates there is no
+	held root.  This feature is not yet implemented so '-' is
+	always returned.
+
+iii) Messages
+
+    create_thin <dev id>
+
+	Create a new thinly-provisioned device.
+	<dev id> is an arbitrary unique 24-bit identifier chosen by
+	the caller.
+
+    create_snap <dev id> <origin id>
+
+	Create a new snapshot of another thinly-provisioned device.
+	<dev id> is an arbitrary unique 24-bit identifier chosen by
+	the caller.
+	<origin id> is the identifier of the thinly-provisioned device
+	of which the new device will be a snapshot.
+
+    delete <dev id>
+
+	Deletes a thin device.  Irreversible.
+
+    trim <dev id> <new size in sectors>
+
+	Delete mappings from the end of a thin device.  Irreversible.
+	You might want to use this if you're reducing the size of
+	your thinly-provisioned device.  In many cases, due to the
+	sharing of blocks between devices, it is not possible to
+	determine in advance how much space 'trim' will release.  (In
+	future a userspace tool might be able to perform this
+	calculation.)
+
+    set_transaction_id <current id> <new id>
+
+	Userland volume managers, such as LVM, need a way to
+	synchronise their external metadata with the internal metadata of the
+	pool target.  The thin-pool target offers to store an
+	arbitrary 64-bit transaction id and return it on the target's
+	status line.  To avoid races you must provide what you think
+	the current transaction id is when you change it with this
+	compare-and-swap message.
+
+'thin' target
+-------------
+
+i) Constructor
+
+    thin <pool dev> <dev id>
+
+    pool dev:
+	the thin-pool device, e.g. /dev/mapper/my_pool or 253:0
+
+    dev id:
+	the internal device identifier of the device to be
+	activated.
+
+The pool doesn't store any size against the thin devices.  If you
+load a thin target that is smaller than you've been using previously,
+then you'll have no access to blocks mapped beyond the end.  If you
+load a target that is bigger than before, then extra blocks will be
+provisioned as and when needed.
+
+If you wish to reduce the size of your thin device and potentially
+regain some space then send the 'trim' message to the pool.
+
+ii) Status
+
+     <nr mapped sectors> <highest mapped sector>