IF YOU WOULD LIKE TO GET AN ACCOUNT, please write an
email to Administrator. User accounts are meant only to access repo
and report issues and/or generate pull requests.
This is a purpose-specific Git hosting for
BaseALT
projects. Thank you for your understanding!
Только зарегистрированные пользователи имеют доступ к сервису!
Для получения аккаунта, обратитесь к администратору.
There have been two file locks used to protect lvm
"global state": "ORPHANS" and "GLOBAL".
Commands that used the ORPHAN flock in exclusive mode:
pvcreate, pvremove, vgcreate, vgextend, vgremove,
vgcfgrestore
Commands that used the ORPHAN flock in shared mode:
vgimportclone, pvs, pvscan, pvresize, pvmove,
pvdisplay, pvchange, fullreport
Commands that used the GLOBAL flock in exclusive mode:
pvchange, pvscan, vgimportclone, vgscan
Commands that used the GLOBAL flock in shared mode:
pvscan --cache, pvs
The ORPHAN lock covers the important cases of serializing
the use of orphan PVs. It also partially covers the
reporting of orphan PVs (although not correctly as
explained below.)
The GLOBAL lock doesn't seem to have a clear purpose
(it may have eroded over time.)
Neither lock correctly protects the VG namespace, or
orphan PV properties.
To simplify and correct these issues, the two separate
flocks are combined into the one GLOBAL flock, and this flock
is used from the locking sites that are in place for the
lvmlockd global lock.
The logic behind the lvmlockd (distributed) global lock is
that any command that changes "global state" needs to take
the global lock in ex mode. Global state in lvm is: the list
of VG names, the set of orphan PVs, and any properties of
orphan PVs. Reading this global state can use the global lock
in sh mode to ensure it doesn't change while being reported.
The locking of global state now looks like:
lockd_global()
previously named lockd_gl(), acquires the distributed
global lock through lvmlockd. This is unchanged.
It serializes distributed lvm commands that are changing
global state. This is a no-op when lvmlockd is not in use.
lockf_global()
acquires an flock on a local file. It serializes local lvm
commands that are changing global state.
lock_global()
first calls lockf_global() to acquire the local flock for
global state, and if this succeeds, it calls lockd_global()
to acquire the distributed lock for global state.
Replace instances of lockd_gl() with lock_global(), so that the
existing sites for lvmlockd global state locking are now also
used for local file locking of global state. Remove the previous
file locking calls lock_vol(GLOBAL) and lock_vol(ORPHAN).
The following commands which change global state are now
serialized with the exclusive global flock:
pvchange (of orphan), pvresize (of orphan), pvcreate, pvremove,
vgcreate, vgextend, vgremove, vgreduce, vgrename,
vgcfgrestore, vgimportclone, vgmerge, vgsplit
Commands that use a shared flock to read global state (and will
be serialized against the prior list) are those that use
process_each functions that are based on processing a list of
all VG names, or all PVs. The list of all VGs or all PVs is
global state and the shared lock prevents those lists from
changing while the command is processing them.
The ORPHAN lock previously attempted to produce an accurate
listing of orphan PVs, but it was only acquired at the end of
the command during the fake vg_read of the fake orphan vg.
This is not when orphan PVs were determined; they were
determined by elimination beforehand by processing all real
VGs, and subtracting the PVs in the real VGs from the list
of all PVs that had been identified during the initial scan.
This is fixed by holding the single global lock in shared mode
while processing all VGs to determine the list of orphan PVs.
Native disk scanning is now both reduced and
async/parallel, which makes it comparable in
performance (and often faster) when compared
to lvm using lvmetad.
Autoactivation now uses local temp files to record
online PVs, and no longer requires lvmetad.
There should be no apparent command-level change
in behavior.
There are likely more bits of code that can be removed,
e.g. lvm1/pool-specific bits of code that were identified
using FMT flags.
The vgconvert command can likely be reduced further.
The lvm1-specific config settings should probably have
some other fields set for proper deprecation.
Previously, a command sent lvmetad new VG metadata in vg_commit().
In vg_commit(), devices are suspended, so any memory allocation
done by the command while sending to lvmetad, or by lvmetad while
updating its cache could deadlock if memory reclaim was triggered.
Now lvmetad is updated in unlock_vg(), after devices are resumed.
The new method for updating VG metadata in lvmetad is in two phases:
1. In vg_write(), before devices are suspended, the command sends
lvmetad a short message ("set_vg_info") telling it what the new
VG seqno will be. lvmetad sees that the seqno is newer than
the seqno of its cached VG, so it sets the INVALID flag for the
cached VG. If sending the message to lvmetad fails, the command
fails before the metadata is committed and the change is not made.
If sending the message succeeds, vg_commit() is called.
2. In unlock_vg(), after devices are resumed, the command sends
lvmetad the standard vg_update message with the new metadata.
lvmetad sees that the seqno in the new metadata matches the
seqno it saved from set_vg_info, and knows it has the latest
copy, so it clears the INVALID flag for the cached VG.
If a command fails between 1 and 2 (after committing the VG on disk,
but before sending lvmetad the new metadata), the cached VG retains
the INVALID flag in lvmetad. A subsequent command will read the
cached VG from lvmetad, see the INVALID flag, ignore the cached
copy, read the VG from disk instead, update the lvmetad copy
with the latest copy from disk, (this clears the INVALID flag
in lvmetad), and use the correct VG metadata for the command.
(This INVALID mechanism already existed for use by lvmlockd.)
The lvm fullreport works per VG and as such, the vg, lv, pv, seg and
pvseg subreport is done for each VG. However, if the PV is not part of
any VG yet, we still want to display pv and pvseg subreports for these
"orphan" PVs - so enable this for lvm fullreport's process_each_vg call.
This refactors the code for autoactivation. Previously,
as each PV was found, it would be sent to lvmetad, and
the VG would be autoactivated using a non-standard VG
processing function (the "activation_handler") called via
a function pointer from within the lvmetad notification path.
Now, any scanning that the command needs to do (scanning
only the named device args, or scanning all devices when
there are no args), is done first, before any activation
is attempted. During the scans, the VG names are saved.
After scanning is complete, process_each_vg is used to do
autoactivation of the saved VG names. This makes pvscan
activation much more similar to activation done with
vgchange or lvchange.
The separate autoactivate phase also means that if lvmetad
is disabled (either before or during the scan), the command
can continue with the activation step by simply not using
lvmetad and reverting to disk scanning to do the
activation.
The lvmetad connection is created within the
init_connections() path during command startup,
rather than via the old lvmetad_active() check.
The old lvmetad_active() checks are replaced
with lvmetad_used() which is a simple check that
tests if the command is using/connected to lvmetad.
The old lvmetad_set_active(cmd, 0) calls, which
stopped the command from using lvmetad (to revert to
disk scanning), are replaced with lvmetad_make_unused(cmd).
Commands already check if the lvmetad token is valid,
and if not, they rescan devices to repopulate lvmetad
before running. Now, in addition to checking the
lvmetad token, they also check if the lvmetad disabled
flag is set. If so, they do not use the lvmetad cache
and revert to disk scanning.
Move checking the lvmetad state, and the possible rescan,
out of lvmetad_send() to the start of the command.
Previously, the token mismatch and rescan would occur
within lvmetad_send() for some other request. Now,
the token mismatch is detected earlier, so the
rescan can be done before the main command is in
progress. Rescanning deep within the processing of
another command will disturb the lvmcache state of
that other command.
A rescan already exists at the start of the command
for the case where foreign VGs are going to be read.
This same rescan is now also performed when there is
an lvmetad token mismatch (from a changed global_filter).
The commands pvscan/vgscan/lvscan/vgimport are excluded
from this preemptive checking/rescanning for lvmetad
because they want to do rescanning themselves explicitly.
If rescanning devices fails, then lvmetad has not been
correctly repopulated and should not be used, so make
the command revert to not using lvmetad.
This command option can be used to trigger a D-Bus
notification independent of the usual notifications
that are sent from other commands as an effect of
changes to PV/VG/LV state. If lvm is not built with
dbus notification support or if notify_dbus is disabled
in the config, this command will exit with an error.
Pass the single vgname as a new process_each_vg arg
instead of setting a cmd flag to tell process_each_vg
to take only the first vgname arg from argv.
Other commands with different argv formats will be
able to use it this way.
This patch replaces "void *handle" with "struct processing_handle *handle"
in process_each_*, process_single_* and related functions.
The struct processing_handle consists of two handles inside now:
- the "struct selection_handle *selection_handle" used for
applying selection criteria while processing process_each_*,
process_single_* and related functions (patches using this
logic will follow)
- the "void* custom_handle" (this is actually the original handle
used before this patch - a pointer to custom data passed into
process_each_*, process_single_* and related functions).
Since commit f12ee43f2e call destroy,
it start to check all VGs are unlocked. However when we become_daemon,
we simply reset locking (since lock is still kept by parent process).
So implement a simple 'reset' flag.
Previously, we have relied on UUIDs alone, and on lvmcache to make getting a
"new copy" of VG metadata fast. If the code which triggers the activation has
the correct VG metadata at hand (the version which is currently on disk), it can
now hand it to the activation code directly.
Accept -q as the short form of --quiet.
Suppress non-essential standard output if -q is given twice.
Treat log/silent in lvm.conf as equivalent to -qq.
Review all log_print messages and change some to
log_print_unless_silent.
When silent, the following commands still produce output:
dumpconfig, lvdisplay, lvmdiskscan, lvs, pvck, pvdisplay,
pvs, version, vgcfgrestore -l, vgdisplay, vgs.
[Needs checking.]
Non-essential messages are shifted from log level 4 to log level 5
for syslog and lvm2_log_fn purposes.
Calling vgscan alone should reuse information from the lvmetad (if running).
The --cache option should initiate direct device scan and update lvmetad
appropriately (if running).
This is mainly for vgscan to behave consistently compared to pvscan.
Remove the checks for vg_read_error() in most of the tools callback
functions and instead make the check in _process_one_vg() more general.
In all but vgcfgbackup, we do not want to proceed if we get any error
from vg_read(). In vgcfgbackup's case, we may proceed if the backup
is to proceed with inconsistent VGs. This is a special case though,
and we mark it with the READ_ALLOW_INCONSISTENT flag passed to
process_each_vg (and subsequently to _process_one_vg).
NOTE: More cleanup is needed in the vg_read_error() path cases.
This patch is a start.
This patch is all just cleanup and no other patch depends on it.
Replace explicit dereference and check with vg_is_exported().
Update a few copyrights and remove unnecessary whitespace.
Should be no functional change.
Sun May 3 12:32:30 CEST 2009 Petr Rockai <me@mornfall.net>
* Rework the toollib interface (process_each_*) on top of new vg_read.
Rebased 6/26/09 by Dave W.
- Add skipping message to process_each_lv
- Remove inconsistent_t.
Several commands calls process_each_vg() and in provided
callback it explicitly recovers VG if inconsistent.
(vgchange, vgconvert, vgscan)
It means that old VG is released and reread but the function
above (process_one_vg) tries to unlock and release old VG.
Patch moves the repair logic into _process_one_vg() function.
It always tries to read vg (even inconsistent) and then decides
what to do according new defined parameter.
Also patch unifies inconsistent error messages.
The only slight change if for vgremove command, where
it now tries to repair VG before it removes if force arg is given.
(It works similar way before, just the order of operation changed).
Fix some memory leaks in error paths found by coverity.
Use C99 struct initialisers.
Move DEFS into configure.h.
Clean-ups to remove miscellaneous compiler warnings.
