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Implementation described in doc/lvm2-raid.txt.
Basic support includes:
- ability to create RAID 1/4/5/6 arrays
- ability to delete RAID arrays
- ability to display RAID arrays
Notable missing features (not included in this patch):
- ability to clean-up/repair failures
- ability to convert RAID segment types
- ability to monitor RAID segment types
The conditional is not just unnecessary, it would have been wrong. The code
is suppose to be checking if the 'splitmirrors_ARG' is negative, but it
instead is checking 'mirrors_ARG'. Rather than changing the argument being
checked, I've pulled the check entirely because 'splitmirrors_ARG' is already
guarenteed to not be negative by virtue of the fact that it is a 'int_arg'.
Negative values will be caught in _process_command_line().
We've used udev fallback code till now to check whether udev
created/removed the entries in /dev correctly and if not,
a repair was done (giving a warning messagea about that).
This patch adds a possibility to enable this additional check
and subsequent fallback only when required (debugging purposes
mostly) and trust udev completely.
So let's disable the fallback code by default and add a new
configuration option "activation/udev_fallback".
(The original code for creating the nodes will still be used
in case the device directory that is set in lvm.conf differs
from the one that udev uses and also when activation/udev_rules
is set to 0 - otherwise we would end up with no nodes/symlinks
at all)
are affected by the move. (Currently it's possible for I/O to become
trapped between suspended devices amongst other problems.
The current fix was selected so as to minimise the testing surface. I
hope eventually to replace it with a cleaner one that extends the
deptree code.
Some lvconvert scenarios still suffer from related problems.
Patch adds check for stripe not only in direct
LV segment but also in mirror image segment.
This prevents bugs like:
# lvcreate -i2 -l10 -n lv vg_test
# lvconvert -m1 -i1 vg_test/lv
# lvreduce -f -l1 vg_test/lv
WARNING: Reducing active logical volume to 4.00 MiB
THIS MAY DESTROY YOUR DATA (filesystem etc.)
Reducing logical volume lv to 4.00 MiB
Segment extent reduction 9 not divisible by #stripes 2
Logical volume lv successfully resized
# lvremove -f vg_test
Segment extent reduction 1 not divisible by #stripes 2
LV segment lv:0-4294967295 is incorrectly listed as being used by LV lv_mimage_0
Internal error: LV segments corrupted in lv_mimage_0.
We should never remove more extents than requested by user,
so round up to next stripe boundary during lvreduce.
Also this fixes round to zero sized LV bug:
# lvcreate -i2 -I 64k -l10 -n lvs vg_test
# lvreduce -f -l1 vg_test/lvs
Rounding size (1 extents) down to stripe boundary size for segment (0 extents)
WARNING: Reducing active logical volume to 0
THIS MAY DESTROY YOUR DATA (filesystem etc.)
Reducing logical volume lvs to 0
Failed to suspend lvs
Before, we used vg_write_lock_held call to determnine the way a device is
opened. Unfortunately, this opened many devices in RW mode when it was not
really necessary. With the OPTIONS+="watch" rule used in the udev rules,
this could fire numerous events while closing such devices (and it caused
useless scans from within udev rules in return).
A common bug we hit with this was with the lvremove command which was unable
to remove the LV since it was being opened from within the udev rules. This
patch should minimize such situations (at least with respect to LVM handling
of devices).
Though there's still a possibility someone will open a device 'outside' in
parallel and fire the event based on the watch rule when closing a device
once opened for RW.
allocates these buffers in such way it adds memory page for each such buffer
and size of unlock memory check will mismatch by 1 or 2 pages.
This happens when we print or read lines without '\n' so these buffers are
used. To avoid this extra allocation, use setvbuf to set these bufffers ahead.
Signed-off-by: Zdenek Kabelac <zkabelac@redhat.com>
Reviewed-by: Milan Broz <mbroz@redhat.com>
Reviewed-by: Petr Rockai <prockai@redhat.com>
Also, add a new 'obtain_device_list_from_udev' setting to lvm.conf with which
we can turn this feature on or off if needed.
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.
allows us to allocate all images of a mirror (or RAID array) at one
time during create.
The current mirror implementation still requires a separate allocation
for the log, however.
As now the FID management is more complex, the code inside free_vg needs
to access some parts of memory pools which were not needed before.
For this - makes the order of unlock_and_free_vg() unconditional.
Keek using unlock_and_free_vg() API function.
For properly working VG locking mechanism only the alphabeting locking
orderer needs to be preserved.
TODO: there could be few more code parts simplified when we 'officially'
support of referencies between different memory pools.
With recent update of dm_report_field_string() API call to accept
completely const objects - we no longer need loose constness here
and keep it forwarding.
When I see 'seg_is_mirrored', I expect the argument to be an lv_segment.
In this case, it is lvcreate_params. Both structures, have a 'segtype'
entry which the macro dereferences. However, it just seems easier to
understand if we do 'segtype_is_mirrored' instead.
Since format instances will use own memory pool, it's necessary to properly
deallocate it. For now, only fid is deallocated. The PV structure itself
still uses cmd mempool mostly, but anytime we'd like to add a mempool
in the struct physical_volume, we can just rename this fn to free_pv and
add the code (like we have free_vg fn for VGs).
While STRIPE_SIZE_LIMIT * 2 is basically UINT_MAX, 32bit integer
value can already overflow durin arg size parsing.
(This really happens in test where --stripesize 4294967291 is used,
in s390x uint overflow and this test is ineffective.)
We allow writing non-orphan PVs only for resize now. The "orphan PV" assert
in pv_write fn uses the "allow_non_orphan" parameter to control this assert.
However, we should find a more elaborate solution so we can remove this
restriction altogether (pv_write together with vg_write is not atomic, we
need to find a safe mechanism so there's an easy revert possible in case of
an error).
Fixing some const warnings - with API change in:
int vg_extend(struct volume_group *vg, int pv_count, const char *const *pv_names,
Change is needed - as lvm2api expects const behaviour here.
So vg_extend() is doing local strdup for unescaping.
skip_dev_dir return const char* from const char* vg_name.
Rest of the patch is cleanup of related warnings.
Also using dm_report_filed_string() API change to simplify
casting in _string_disp and _lvname_disp.
Add configurable option to define minimal size of
of block device usable as a PV.
pv_min_size() is added to lvm-globals and it's being
initialized through _process_config.
Macro PV_MIN_SIZE is unused and removed.
New define DEFAULT_PV_MIN_SIZE_KB is added to lvm-global
and unlike PV_MIN_SIZE it uses KB units.
Should help users with various slow devices attached to the system,
which cannot be easily filtered out (like FDD on /dev/sdX):
https://bugzilla.redhat.com/show_bug.cgi?id=644578
Make configurable default behaviour how to deal with device node creates.
With udev system natural options should be 'resume'.
For older systems where user expect there is node in /dev/mapper immediately
after dmsetup create --notable - use 'create'
FIXME:
Code needs fixing passing this flag through udev cookie.
activated.
In order to achieve this, we need to be able to query whether
the origin is active exclusively (a condition of being able to
add an exclusive snapshot).
Once we are able to query the exclusive activation of an LV, we
can safely create/activate the snapshot.
A change to 'hold_lock' was also made so that a request to aquire
a WRITE lock did not replace an EX lock, which is already a form
of write lock.
Add new function dm_task_set_add_node() to select between 2 types
of node creation in device directory.
DM_ADD_NODE_ON_RESUME is now default and ensures node is created on
resume. Old original behavior is accessible with DM_ADD_NODE_ON_CREATE.
In this case node would be created during dmsetup create --notable.
For the user 2 new options for dmsetup create are added:
[{--addnodeonresume | --addnodeoncreate }]
Properly working node creation on resume is needed for proper operation
stacking and ability to correctly check in which state the device should
after whole udev transation.
As sync_local_dev_names() cannot be called within activation context,
add new parametr which allows to select if the sync call is needed
before executing new command.
a mirror image (or removing a log while adding a mirror). Advise the
user to use two separate commands instead.
This issue become especially problematic when PVs are specified, as they
tend to mean different things when adding vs removing. In a command that
mixes adding and removing, it is impossible to decern exactly what the
user wants.
This change prevents bug 603912.
Patch adds extra check for lv_name not being NULL.
Test avoids unneeded strlen call for this case.
Otherwise there is no functional change as test would fail on
size_t comparation even for NULL lv_name (thus there is no risk
of NULL dereference when taking 'true' if branch.
Add test for NULL before passing uuid as src argument to memcpy.
As memcpy function is declared as function not accepting NULL.
Though we pass NULL only with zero length so this patch presents
no functional change to the code.
was lacking the (vgmem) pool. We now create that pool. There is at least one
more such VG (_dummy_vg) which is pool-less. I am not sure what is the right
way to go about this, but this is currently necessary to fix a segfault
introduced by using vgmem in the reporter in Dave's lvseg lvm2app patches.
Signed-off-by: Petr Rockai <prockai@redhat.com>
Patch updates exec_cmd() and adds 3rd parameter with pointer for
status value, so caller might examine returned status code.
If the passed pointer is NULL, behavior is unmodified.
Patch allows to confinue with lvresize if the failure from fsadm check is
caused by mounted filesystem as many of filesystem resize tools do support
online filesystem resize. (originally user had to use flag '-n' to bypass
this filesystem check)
Simultaneous -a and --refresh is not valid.
poll+monitor are valid together with or without -ay* (but not with -an*)
No longer print polling results summary if no LVs in the VG were polled.
Makes clang happier as it covers all code paths and avoids NULL pointer
dereference through the 'com' pointer (which is NULL by default static
initialisation).
Reported by clang as: Argument with 'nonnull' attribute passed null
Reuse the result of the last strchr() call - make sure, 'st' point is not
null for the next strchr() call.
to lvm.conf in the activation section: 'snapshot_autoextend_threshold' and
'snapshot_autoextend_percent', that 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.
Reorder linked libraries so we better support --as-needed linker flag used
by some distributions (i.e. Gentoo).
Patch suggested by Diego Elio Pettenò <flameeyes <at> gmail.com>
page.
Add ->target_name to segtype_handler to allow a more specific target
name to be returned based on the state of the segment.
Result of trying to merge a snapshot using a kernel that doesn't have
the snapshot-merge target:
Before:
# lvconvert --merge vg/snap
Can't expand LV lv: snapshot target support missing from kernel?
Failed to suspend origin lv
After:
# lvconvert --merge vg/snap
Can't process LV lv: snapshot-merge target support missing from kernel?
Failed to suspend origin lv
Unable to merge LV "snap" into it's origin.
re-add a physical volume that has gone missing previously, due to a transient
device failure, without re-initialising it.
Signed-off-by: Petr Rockai <prockai@redhat.com>
Reviewed-by: Alasdair Kergon <agk@redhat.com>
may never complete.
If you convert from a linear to a mirror and then convert that
mirror back to linear /while/ the previous (up)convert is
taking place, the mirror polling process will never complete.
This is because the function that polls the mirror for
completion doesn't check if it is still polling a mirror and
the copy_percent that it gets back from the linear device is
certainly never 100%.
The fix is simply to check if the daemon is still looking at
a mirror device - if not, return PROGRESS_CHECK_FAILED.
The user sees the following output from the first (up)convert
if someone else sneaks in and does a down-convert shortly
after their convert:
[root@bp-01 ~]# lvconvert -m1 vg/lv
vg/lv: Converted: 43.4%
ABORTING: Mirror percentage check failed.
If pvmove crashed and metadata contains pvmove LV
but without miorrored segments, pvmove --abort
will not repair the situation (and finish wth success!).
Fix it by allowing metadata update if aborting
(thus removing pvmove LV) even if no moved LVs detected.
(Tested on real metadata provided by an lvm user:-)
This is not only undocumented but is is also in violation with --help
documentation.
Using --yes without --force is useful in pvcreate when it detects
old signature.
Ignore snapshots when performing mirror recovery beneath an origin.
Pass LCK_ORIGIN_ONLY flag around cluster.
Add suspend_lv_origin and resume_lv_origin using LCK_ORIGIN_ONLY.
Introduce --norestorefile to allow user to override the new requirement.
This can also be overridden with "devices/require_restorefile_with_uuid"
in lvm.conf -- however the default is 1.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
An incorrect fix on July 13, 2010 for an annoyance has caused a regression.
The offending check-in was part of the 2.02.71 release of LVM. That
check-in caused any PVs specified on the command line to be ignored when
performing a mirror split.
This patch reverses the aforementioned check-in (solving the regressions)
and posits a new solution to the list reversal problem. The original
problem was that we would always take the lowest mimage LVs from a mirror
when performing a split, but what we really want is to take the highest
mimage LVs. This patch accomplishes that by working through the list in
reverse order - choosing the higher numbered mimages first. (This also
reduces the amount of processing necessary.)
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Reviewed-by: Takahiro Yasui <takahiro.yasui@hds.com>
all but one mirror leg.
<patch header>
To handle a double failure of a mirrored log, Jon's two patches are
commited, however, lvconvert command can't still handle an error
when mirror leg and mirrored log got failure at the same time.
[Patch]: Handle both devices of a mirrored log failing (bug 607347)
posted: https://www.redhat.com/archives/lvm-devel/2010-July/msg00009.html
commit: https://www.redhat.com/archives/lvm-devel/2010-July/msg00027.html
[Patch]: Handle both devices of a mirrored log failing (bug 607347) -
additional fix
posted: https://www.redhat.com/archives/lvm-devel/2010-July/msg00093.html
commit: https://www.redhat.com/archives/lvm-devel/2010-July/msg00101.html
In the second patch, the target type of mirrored log is replaced with
error target when remove_log is set to 1, but this procedure should be
also used in other cases such as the number of mirror leg is 1. This
patch relocates the procedure to the main path.
In addition, I added following three changes.
- Removed tmp_orphan_lvs handling procedure
It seems that _delete_lv() can handle detached_log_lv properly
without adding mirror legs in mirrored log to tmp_orphan_lvs.
Therefore, I removed the procedure.
- Removed vg_write()/vg_commit()
Metadata is saved by vg_write()/vg_commit() just after detached_log_lv
is handled. Therefore, I removed vg_write()/vg_commit().
- With Jon's second patch, we think that we don't have to call
remove_mirror_log() in _lv_update_mirrored_log() because will be
handled remove_mirror_images() in _lvconvert_mirrors_repaire().
</patch header>
Signed-off-by: Takahiro Yasui <takahiro.yasui@hds.com>
Reviewed-by: Petr Rockai <prockai@redhat.com>
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
The cluster log daemon (cmirrord) is not multi-threaded and
can handle only one request at a time. When a log is stacked
on top of a mirror (which itself contains a 'core' log), it
creates a situation that cannot be solved without threading.
When the top level mirror issues a "resume", the log daemon
attempts to read from the log device to retrieve the log
state. However, the log is a mirror which, before issuing
the read, attempts to determine the 'sync' status of the
region of the mirror which is to be read. This sync status
request cannot be completed by the daemon because it is
blocked on a read I/O to the very mirror requesting the
sync status.
With mirror_log_fault_policy of 'remove' and mirror_image_fault_policy
of 'allocate', the log type of the mirror volume is converted from
'disk' or 'mirrored' to 'core' when all mirror legs but one in a mirror
volume broke.
Keep new_log_count as a number of valid log devices by using log_count
variable for a temporary usage in the first phase of error recovery
in _lvconvert_mirrors_repair().
Signed-off-by: Takahiro Yasui <takahiro.yasui@hds.com>
Reviewed-by: Petr Rockai <prockai@redhat.com>
When splitting off mirror images from a mirror, we always take
LVs from the end of a list. For example, if the mirror sub-devices
are lv_mimage_[012], we should select lv_mimage_2 if splitting off
one image. However, lv_mimage_0 was being selected instead.
The problem came from calling '_move_removable_mimages_to_end'
when it was unnecessary to do so. When the user /does/ specify
specific devices to be removed, this function properly moved the
appropriate LVs to the end of the list for extraction. However,
if the user /doesn't/ give any specific PVs, the function should
do nothing. '_move_removable_mimages_to_end' was keying off of
whether 'removable_pvs' was NULL or not and this value was
improperly being populated with the set of all available PVs.
This was causing '_move_removable_mimages_to_end' to completely
reverse the list, which in turn caused us to extract the
hithertofore front-of-the-list LVs.
An unhandled condition allowed the command to terminate
cleanly without a warning. Added a check for the
'--splitmirrors' argument to allow execution to the lower
level function that has the check to see if the user is
trying to split a linear device. You should now see a
message if you try to use --splitmirrors on a linear device.
Pass metadataignore through PV creation / setup paths.
As a result of this cleanup, we can remove the unnecessary setting
of mda_ignore bits inside pvcreate_single(), after call to pv_create.
For now, just set metadataignore to '0' in some places. This is
equivalent to the prior functionality, although the 0 is given
by the caller not hardcoded in _mda_setup() call.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
When using vgmetadatacopies value other than "umanaged" (0), prompt
the user if the usage of --metadataignore would change the value of
vgmetadatacopies. The main 2 cases are:
1) pvchange --metadataignore
2) vgextend --metadataignore
We leave the prompt check in the tools, and do not change anything
if the user says 'n'.
Examples:
vgextend --metadataignore y vgtest /dev/loop0
Setting metadataignore will override preferred number of copies of VG vgtest metadata.
Are you sure? [y/n]: y
No physical volume label read from /dev/loop0
Physical volume "/dev/loop0" successfully created
Volume group "vgtest" successfully extended
pvchange --metadataignore y /dev/loop3
Setting metadataignore on /dev/loop3 will override preferred number of copies of VG vgtest metadata.
Are you sure? [y/n]: y
WARNING: Changing preferred number of copies of VG vgtest metadata from 3 to 2
Physical volume "/dev/loop3" changed
1 physical volume changed / 0 physical volumes not changed
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Rather than attempting to remove all the images of a mirrored
log volume via remove_mirror_images, simply remove the log
if all its devices have failed.
Taka was the first to report that there is still an outstanding
issue with handling this case. I've managed to reproduce it
only very rarely, and am still working on identifying the problem.
Failing to handle the problem rarely is better than not handling
the scenario at all, so I'm checking this in.
Allow metadataignore flag to be passed in to pvcreate.
Ideally, more refactoring of the mda allocation / initialization
is warranted, but for now, we just add another parameter to 'add_mda'
to take an existing mda ignored flag. We need to do this or pv_write
loses the state of the mda 'ignored' flag before copying and writing
to disk.
In preparation to call this from both pvcreate as well as pvchange,
move the guts of metadataignore into a library function.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Allowing an 'all' and 'unmanaged' value is more intuitive, and
provides a simple way for users to get back to original LVM behavior
of metadata written to all PVs in the volume group.
If the user requests "--vgmetadatacopies unmanaged", this instructs
LVM not to manage the ignore bits to achieve a specific number of
metadata copies in the volume group. The user is free to use
"pvchange --metadataignore" to control the mdas on a per-PV basis.
If the user requests "--vgmetadatacopies all", this instructs LVM
to do 2 things: 1) clear all ignore bits, and 2) set the "unmanaged"
policy going forward.
Internally, we use the special MAX_UINT32 value to indicate 'all'.
This 'just' works since it's the largest value possible for the
field and so all 'ignore' bits on all mdas in the VG will get
cleared inside _vg_metadata_balance(). However, after we've
called the _vg_metadata_balance function, we check for the special
'all' value, and if set, we write the "unmanaged" value into the
metadata. As such, the 'all' value is never written to disk.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Now that we have both --pvmetadatacopies and --vgmetadatacopies,
we need to make sure --metadatacopies gets interpreted correctly.
For pv commands, --metadatacopies should imply --pvmetadatacopies,
and for vg commands, --vgmetadatacopies.
Note: this will change the behavior of vgcreate with --metadatacopies
to be a synonym for --vgmetadatacopies. Previously, --metadatacopies
would apply to any PVs given with vgcreate that needed an implicit
pvcreate. As a result, one small change is needed to one of the nightly
tests - t-vgcreate-usage.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
When vgmerge is called we move the mdas from the source to the
destination. With metadata balancing we now have another mda
list, fid->metadata_areas_ignored, so move the mdas on this list
as well.
This patch should not matter as the code is written today. However
we include it for completeness in the case that _vgmerge_single()
is refactored and/or moved into a library function.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Allow parsing of --vgmetadatacopies for vgcreate. Accept
--metadatacopies as a synonym for --vgmetadatacopies.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
When a user explicitly sets a new mda ignore value for a PV, we
should update vg_mda_copies accordingly. When the VG is written
out, the user would not want the new ignore state to get lost as
a result of the vg_mda_copies value and logic in the vg_write
path.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Update logic in vgchange to handle --vgmetadatacopies, allow
--metadatacopies as a synonym to --vgmetadatacopies,
and add these parameters to args.h and commands.h
Forbit both --vgmetadatacopies and --metadatacopies as only
one allowed.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Add a field to struct volume_group to later implement metadata
balancing:
- mda_copies: target # of non-ignored mdas in the VG; default 0 (do
not control pv 'ignore mdas' bit.
This patch just adds the parameter to the structures with the default
values but does not modify any commands. Should be no functional change.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
This patch just modifies pvchange to call the underlying ignore
functions for mdas. Ensure special cases do not reflect changes
in metadata (PVs with 0 mdas, setting ignored when already ignored,
clearing ignored when not ignored).
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
the failure of a device that contained both a image of
a mirror and an image of the mirrored log. The order
of the handling of those faults was important (and
wrong), this patch corrects that.
Patch-From: Takahiro Yasui <tyasui@redhat.com>
Activate only the first replicator-dev LV, that activates all other
related LVs from Replicator. In case of error during this activation,
it will not retry again for other heads (less confusing error log).
As for _process_one_vg() we need similar retry loop for
process_each_lv_in_vg(). This patch retries to process
failed LVs with reopened VGs.
Patch does not add any extra repeated invocations if there is not
found any missing VG during LV processing.
Patch modifes behavior of _process_one_vg().
In the first pass vg_read() collectis for replicator sorted list of
additional VGs during lock_vol().
If any other VG is needed by the replicator and it is not yet opened
then next iteration loop is taken with all collected VGs.
Flag vg->cmd_missing_vgs detects missing VGs.
Patch adds failed_lvnames to the list of parameters for process_each_lv_in_vg().
If the list is not NULL it will be filled with LV names of failing LVs
during function execution.
Application could later reiterate only on failed LVs.
Earlier patches added some infrastructure to lookup a vgname from
a pvname. We now can cleanup some of the pvchange and other code
by requiring callers that want to modify some pv property:
1) lookup the vgname by the pvname
2) use the vgname to obtain a vg handle
3) get the pv handle from the vg handle
This should work going forward and be a much cleaner interface,
as we move away from pvs as standalone objects.
A shortcut for --ignorelockingfailure, --ignoremonitoring, --poll n options
and LVM_SUPPRESS_LOCKING_FAILURE_MESSAGES environment variable used all at
once in initialisation scripts (e.g. rc.sysinit or initrd).
We can use it even in read-only environment where a try to initialise
file-based locking fails (not to mention other processing related with
lvm2 init). Simply, we want to output the version only, nothing else.
And this should always work.
