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LVM has restricter character set that is allowed for VG-LV names
and the dm names constructed do not contain any blacklisted characters
that would require name mangling.
Also, when any other device-mapper device is scanned that could
possibly contain such blacklisted characters, we reference the
device by its major:minor instead of dm name (e.g. _device_is_usable fn).
The "default.profile" name was misleading. It's actually a helper
*template* that can be used for copying and further editing to create
a new profile.
Also, we have separate command and metadata profiles now so the templates
are separated as well - we can't mix profile settings from one group with
another - such profile is rejected by lvm tools.
Warn user before converting volume to different type.
WARNING: Converting vg/lvol0 logical volume to pool's meta/data volume.
THIS WILL DESTROY CONTENT OF LOGICAL VOLUME (filesystem etc.)
Since the content of volume is lost we have to query user to confirm
such operation. If user is 100% sure, he may use '--yes' to avoid prompts.
The dumpconfig now understands --commandprofile/--profile/--metadataprofile
The --commandprofile and --profile functionality is almost the same
with only one difference and that is that the --profile is just used
for dumping the content, it's not applied for the command itself
(while the --commandprofile profile is applied like it is done for
any other LVM command).
We also allow --metadataprofile for dumpconfig - dumpconfig *does not*
touch VG/LV and metadata in any way so it's OK to use it here (just for
dumping the content, checking the profile validity etc.).
The validity of the profile can be checked with:
dumpconfig --commandprofile/--profile/--metadataprofile --validate
...depending on the profile type.
Also, mention --config in the dumpconfig help string so users know
that dumpconfig handles this too (it did even before, but it was not
documented in the help string).
- When defining configuration source, the code now uses separate
CONFIG_PROFILE_COMMAND and CONFIG_PROFILE_METADATA markers
(before, it was just CONFIG_PROFILE that did not make the
difference between the two). This helps when checking the
configuration if it contains correct set of options which
are all in either command-profilable or metadata-profilable
group without mixing these groups together - so it's a firm
distinction. The "command profile" can't contain
"metadata profile" and vice versa! This is strictly checked
and if the settings are mixed, such profile is rejected and
it's not used. So in the end, the CONFIG_PROFILE_COMMAND
set of options and CONFIG_PROFILE_METADATA are mutually exclusive
sets.
- Marking configuration with one or the other marker will also
determine the way these configuration sources are positioned
in the configuration cascade which is now:
CONFIG_STRING -> CONFIG_PROFILE_COMMAND -> CONFIG_PROFILE_METADATA -> CONFIG_FILE/CONFIG_MERGED_FILES
- Marking configuration with one or the other marker will also make
it possible to issue a command context refresh (will be probably
a part of a future patch) if needed for settings in global profile
set. For settings in metadata profile set this is impossible since
we can't refresh cmd context in the middle of reading VG/LV metadata
and for each VG/LV separately because each VG/LV can have a different
metadata profile assinged and it's not possible to change these
settings at this level.
- When command profile is incorrect, it's rejected *and also* the
command exits immediately - the profile *must* be correct for the
command that was run with a profile to be executed. Before this
patch, when the profile was found incorrect, there was just the
warning message and the command continued without profile applied.
But it's more correct to exit immediately in this case.
- When metadata profile is incorrect, we reject it during command
runtime (as we know the profile name from metadata and not early
from command line as it is in case of command profiles) and we
*do continue* with the command as we're in the middle of operation.
Also, the metadata profile is applied directly and on the fly on
find_config_tree_* fn call and even if the metadata profile is
found incorrect, we still need to return the non-profiled value
as found in the other configuration provided or default value.
To exit immediately even in this case, we'd need to refactor
existing find_config_tree_* fns so they can return error. Currently,
these fns return only config values (which end up with default
values in the end if the config is not found).
- To check the profile validity before use to be sure it's correct,
one can use :
lvm dumpconfig --commandprofile/--metadataprofile ProfileName --validate
(the --commandprofile/--metadataprofile for dumpconfig will come
as part of the subsequent patch)
- This patch also adds a reference to --commandprofile and
--metadataprofile in the cmd help string (which was missing before
for the --profile for some commands). We do not mention --profile
now as people should use --commandprofile or --metadataprofile
directly. However, the --profile is still supported for backward
compatibility and it's translated as:
--profile == --metadataprofile for lvcreate, vgcreate, lvchange and vgchange
(as these commands are able to attach profile to metadata)
--profile == --commandprofile for all the other commands
(--metadataprofile is not allowed there as it makes no sense)
- This patch also contains some cleanups to make the code handling
the profiles more readable...
The dumpconfig reuses existing config_def_check results in case
the check is done during general lvm command context initialization
(when enabled by config/checks=1) so dumpconfig does not need to run
the same check again during its execution, hence saving some time.
However, we don't check for differences from defaults during general
lvm command initialization as it's useless at that time. It makes
sense only in case when such a check is directly requested (like in
the case of lvm dumpconfig --type diff). We need to take care that
the reused information was already produced with this "diff" checking
before and if not, we need to force the check so the check status also
gathers the new "diff" info now.
Also, do not do diff checking for any other dumpconfig command that
is run after dumpconfig --type diff.
When cmd refresh is called, we need to move any already loaded profiles
to profiles_to_load list which will cause their reload on subsequent
use. In addition to that, we need to take into account any change
in config/profile configuration setting on cmd context refresh
since this setting could be overriden with --config.
Also, when running commands in the shell, we need to remove the
global profile used from the configuration cascade so the profile
is not incorrectly reused next time when the --profile option is
not specified anymore for the next command in the shell.
This bug only affected profile specified by --profile cmd line
arg, not profiles referenced from LVM metadata.
Since decisions in the silent mode may not be always obvious,
print skipped prompt with answer 'n'.
Also document '-qq' behaviour (single -q only shuts
logging, while -qq sets silent mode).
Share DM_REPORT_FIELD_RESERVED_NAME_{HELP,HELP_ALT} between libdm and
any libdm user to handle reserved field names, in this case the virtual
field name to show help instead of failing on unrecognized field.
The libdm user also needs to check the field name so it can fire
proper code in this case (cleanup, exit etc.).
Support upto 3 levels os nesting signal blocking.
As of today - code blocks signals immediatelly when it opens
VG in read-write mode - this however makes current prompt usage
then partially unusable since user may not 'break' command
during prompt (something most user would expect).
Until a better fix for prompting is implemented, put in support
for signal nesting - thus when prompt enables signal acceptance,
make it possible to really break command at this point.
When quering for dmeventd monitoring status, check first
if lvm2 is configured to monitor to avoid unwanted start
of dmeventd process for answering monitoring status.
When showing ACTIVE status for snapshot's origin,
avoid testing all its snapshot - it's not useful
to tell user origin is inactivate, while it's clearly
available and running - just one of its snapshot leg
is invalid...
Relocate info from thin pool and thin volume segments
to proper code section for segments.
Add discards and thin count status info.
Info is shown with 'lvdisplay --maps' (like for other segments).
For percentage display we need -tpool - so check for layered
device presence here instead of plain pool device.
Also update 'info' - so when pool is 'available' we
display open count for -tpool device instead of mostly
irrelevant pool.
TODO: Maybe we should actually display this open info always?
(even when just -tpool is available, but pool is not)
Emphesize virtual extents for virtual LVs and for
those use 'Virtual extents' instead of 'Logical extents',
so it's immeditatelly visible, which extents do have
straighforward physical backend.
While the 'raid1/10' segment types were being handled inadvertently
by '_move_mirrors()', the parity RAIDs were not being properly checked
to ensure that the user had specified all necessary PVs when moving
them. Thus, internal errors were being triggered when only part of
a RAID LV was moved to the new VG. I've added a new function,
'_move_raid()', which properly checks over any affected RAID LVs and
ensures that all the necessary PVs are being moved.
ignore_suspended_devices=0 is already used in lvm.conf we distribute,
but it was still "1" in the code (so it was used when lvm.conf value
was not defined). It should be "0" too.
Config variables that are processed during setup prior to calling into
particular tools must not be accessed directly afterwards in case the
values already got overridden.
_process_config() already used the tests I'm removing here to call
lvmetad_set_active() and set up lvmetad_used().
This should be the preferred way of configuring lvm2 for udev/systemd
since otherwise one can end up with the processes run from udev (the
pvscan we run for lvmetad update on events) to be killed prematurely
and this can end up with LVM volumes not activated in the end.
This is sort of info we always ask people to retrieve when
inspecting problems in systemd environment so let's have this
as part of lvmdump directly.
The -s option does not need to be bound to systemd only. We could
add support for initscripts or any other system-wide/service tracking
info that can help us with debugging problems.
Set A_POSITIONAL_FILL if the array of areas is being filled
positionally (with a slot corresponding to each 'leg') rather
than sequentially (with all suitable areas found, to be sorted
and selected from).
Prior adding new reply to the list, check
if the reply thread is not already finished.
In that case discard adding message
(which would otherwise be leaked).
Use mutex to access localsock values, so check
num_replies when the thread is not yet finished.
Check for threadid prior the mutex taking
(though this check is probably not really needed)
Added complexity with extra reply mutex is not worth the troubles.
The only place which may slightly benefit from this mutex is timeout
and since this is rather error case - let's convert it to
localsock.mutex and keep it simple.
Move the pthread mutex and condition creation and destroy
to correct place right after client memory is allocatedd
or is going to be released.
In the original place it's been in race with lvm thread
which could have still unlock mutex while it's been already
destroyed.
When TEST_MODE flag is passed around the cluster,
it's been use in thread unprotected way, so it may have
influenced behaviour of other running parallel lvm commands
(activation/deactivation/suspend/resume).
Fix it by set/query function only under lvm mutex.
For hold_un/lock function calls check lock_flags bits directly.
When pvmove0 is finished, it replaces temporarily pvmove0
with error segment, however in this case, pvmove0 remains
unremovable in case pvmove --abort is interrupted in this
moment - since it's not a pvmove anymore and normal
lvremove can't be used to remove LOCKED lv.
There were two bugs before when using pvcreate --restorefile together
with data alignment and its offset specified:
- the --dataalignment was always ignored due to missing braces in the
code when validating the divisibility of supplied --dataalignment
argument with pe_start which we're just restoring:
if (pp->rp.pe_start % pp->data_alignment)
log_warn("WARNING: Ignoring data alignment %" PRIu64
" incompatible with --restorefile value (%"
PRIu64").", pp->data_alignment, pp->rp.pe_start);
pp->data_alignment = 0
The pp->data_alignment should be zeroed only if the pe_start is not
divisible with data_alignment.
- the check for compatibility of restored pe_start was incorrect too
since it did not properly count with the dataalignmentoffset that
could be supplied together with dataalignment
The proper formula is:
X * dataalignment + dataalignmentoffset == pe_start
So it should be:
if ((pp->rp.pe_start % pp->data_alignment) != pp->data_alignment_offset) {
...ignore supplied dataalignment and dataalignment offset...
}
This test for LV name restriction check name of device is below 128
chars (which is enforced by dm target).
Thus it should not count with device name.
(Though the test for PATH_MAX size should be probably also added,
but this is runtime test, since theoretically devpath might differ in cluster)
It's unclear why we should prohibit use of -v output.
So reenable (like with other 'display' tools)
But -c -m is really unsupported - return invalid cmd.
Sort order for -C|--columns as with other options,
and use short capital name as the first (as with other options).
Also drop multiple reference for pvs/lvs/vgs, since now
the text for -C is really close to referrence of lvm anyway.
Drop unused passed cmd pointer from function.
TODO:
We have two similar functions (though not identical)
lv_manip.c: for_each_sub_lv()
metadata.c: _lv_each_dependency()
They seem to not always match - we should probably convert
to use only a single function.
Use proper vgmem memory pool for allocation of LV name in the vg
and check if new renamed LV is a valid name.
TODO: validation should really use also VG name, othewise we are not
able to tell "vgname-lvname" will be valid.
Commit 1a832398a7 moved
some code from _pvchange_single() to main pvchange() and
introduced exit code regression as return codes have not
been properly changed, thus pvchange command exited
with '0' exit code, even though it has reported error.
Also there is a missing vg unlock in error path.
Fix it by counting the total number of expected calls before
checking for pvname and also unlock and relase vg when
pv is not found.
For a quick overview of config when debugging and to quickly check
which values are different from defaults and which are not defined
in the config and for which defaults are used.
When lvm2 command works with clvmd and uses locking in wrong way,
it may 'leak' certain file descriptors in opened (incorrect) state.
dev_cache_exit then destroys memory pool of cached devices, while
_open_devices list in dev-io.c was still referencing them if they
were still opened.
Patch properly calls _close() function to 'self-heal' from this
invalid state, but it will report internal error (so execution
with abort_on_internal_error causes immediate death). On the
normal 'execution', error is only reported, but memory state is
corrected, and linked list is not referencing devices from
released mempool.
For crash see: https://bugzilla.redhat.com/show_bug.cgi?id=1073886
Smallest supported size for swap device is 40KB, however current
test skipped devices smaller then 4096 sectors (2MB).
Since page is in bytes, convert it to sectors before comparing
with device size (in sectors).
pvscan --uuid was broken since it was using only 128 char buffers
without checking any write size, so any longer device path leads to
crash.
Also ansure format is properly aligned into columns with this option.
The PV size is displayed in sectors, not kilobytes
for 'pvdisplay -c'
Signed-off-by: Thomas Fehr <fehr@suse.de>
Acked-by: Hannes Reinecke <hare@suse.de>
Instead of sending repeatedly LOCAL_SYNC commands to clvmds
like 'lvs', rememeber the last sent commmand, and if there was no other
clvmd command, drop this redundant SYNC call message.
The problem has started with commit:
56cab8cc03
This introduced correct synchronisation of name, when user requests to know
open_count (needs to wait for udev), however it is also executed for
read-only cases like 'lvs' command.
For now implement very simple solution, which is only monitoring
outgoing clvmd command, and when sequence of LOCAL sync names are
recognized, they are skipped automatically.
TODO:
Future solution might move this variable info 'cmd_context' and
use 'needs_sync' flag also i.e. in file locking code.
When the backup is disabled, avoid testing backup presence.
This only leads to errors being logged in debug trace and the missing
backup can't be fixed, since it's disabled.
Check whether lvm dumpconfig --mergedconfig is used only
with --type current (where we're merging current config and
the config supplied on command line). With other types
the config was merged, but it was thrown away since we're
generating other type of config anyway. This lead to a memleak.
Error out if --mergedconfig is used with anything else than
--type current (or without specifying --type in which case
the --type current is used by default).
Do not allow conversion of too small LV into a COW snapshot device.
Without this patch snapshot target is generating these kernel
messages before creation fails:
attempt to access beyond end of device
dm-9: rw=16, want=8, limit=2
attempt to access beyond end of device
...
device-mapper: table: 253:11: snapshot: Failed to read snapshot metadata
device-mapper: ioctl: error adding target to table
device-mapper: reload ioctl on failed: Input/output error
Usage of origin as a snapshot 'COW' volume is unsupported.
Without this test lvm2 is able to generate this ugly internal error message.
To test this:
lvcreate -L1 -n lv1 vg
lvcreate -L1 -n lv2 -s vg/lv1
lvcreate -L1 -n lv3 vg
lvconvert -s vg/lv3 vg/lv1
Internal error: LVs (5) != visible LVs (1) + snapshots (1) + internal LVs (0) in VG vg
Users can create several profiles for how the tools report
the output very easily and then just use
<lvm reporting command> --profile <report_profile_name>
This prevents numerous VG refreshes on each "pvscan --cache -aay" call
if the VG is found complete. We need to issue the refresh only if the PV:
- is new
- was gone before and now it reappears (device "unplug/plug back" scenario)
- the metadata has changed
Let's do this the other way round - this makes more logic than commit b995f06.
So let's allow empty values for global/thin_disabled_features where
such an empty value now means "none of this features are disabled".
The empty pool is also the pool which has yet queued list of messages
and transaction_id == 1.
Problem is exposed when pool is created inactive.
lvcreate -L10 -T vg/pool -an
lvcreate -V10 -T vg/pool
When pool_has_message() is queried with NULL lv and 0 device_id
it should just return 'true' when there is any message queued.
So it needs to return negative value dm_list_empty().
Since there is no user for this code path in code currently,
this bug has not been triggered.
This patch will releases allocated private resources from
startup. Needs previous dm_zalloc patch to ensure unset
private pointer is NULL.
TODO: check on real cluster.
Based on patch:
https://www.redhat.com/archives/lvm-devel/2014-March/msg00015.html
The CPPFunction typedef (among others) have been deprecated in favour of
specific prototyped typedefs since readline 4.2 (circa 2001).
It's been working since because compatibility typedefs have been in
place until they where removed in the recent readline 6.3 release.
Switch to the new style to avoid build breakage.
But also add full backward compatibility with define.
Signed-off-by: Gustavo Zacarias <gustavo zacarias com ar>
If the PV label is lost (e.g. by doing a dd on the device), call
"systemd-run pvscan --cache <major>:<minor>" in 69-dm-lvm-metad.rules
to inform lvmetad about this state.
The reason for this is that ENV{SYSTEMD_WANTS}="lvm2-pvscan@<major>:<minor>"
logic will not cause the pvscan to be fired in this case since this works
only on proper device addition/removal cycle - the lvm2-pvscan service's
ExecStop is called only on proper REMOVE event - the service is bound to
device existence. Hence we need pvscan call via systemd-run (that
instantiates a quick transient service just to call the command).
See also https://bugzilla.redhat.com/show_bug.cgi?id=1063813.
Code uses target driver version for better estimation of
max size of COW device for snapshot.
The bug can be tested with this script:
VG=vg1
lvremove -f $VG/origin
set -e
lvcreate -L 2143289344b -n origin $VG
lvcreate -n snap -c 8k -L 2304M -s $VG/origin
dd if=/dev/zero of=/dev/$VG/snap bs=1M count=2044 oflag=direct
The bug happens when these two conditions are met
* origin size is divisible by (chunk_size/16) - so that the last
metadata area is filled completely
* the miscalculated snapshot metadata size is divisible by extent size -
so that there is no padding to extent boundary which would otherwise
save us
Signed-off-by:Mikulas Patocka <mpatocka@redhat.com>
While stripe size is twice the physical extent size,
the original code will not reduce stripe size to maximum
(physical extent size).
Signed-off-by: Zhiqing Zhang <zhangzq.fnst@cn.fujitsu.com>
When read-only snapshot was created, tool was skipping header
initialization of cow device. If it happened device has been
already containing header from some previous snapshot, it's
been 'reused' for a newly created snapshot instead of being cleared.
To make "lvm dumpconfig --type default" output to be usable like any
other config, we need to comment out lines that have no default value
defined. Otherwise, we'd have the output with config options
with blank or zero values which is not the same as when the value
is not defined! And such configuration can't be feed into lvm again
without further edits. So let's fix this.
Currently this covers these configuration options exactly:
devices/loopfiles
devices/preferred_names
devices/filter
devices/global_filter
devices/types
allocation/cling_tag_list
global/format_libraries
global/segment_libraries
activation/volume_list
activation/auto_activation_volume_list
activation/read_only_volume_list
activation/mlock_filter
metadata/dirs
metadata/disk_areas
metadata/disk_areas/<disk_area>
metadata/disk_areas/<disk_area>/start_sector
metadata/disk_areas/<disk_area>/size
metadata/disk_areas/<disk_area>/id
tags/<tag>
tags/<tag>/host_list
Reorder detection of cmirrord. Now if cmirrord is not
running, target will not try to load kernel log module,
for communication with cmirrord.
Whole check for attrs now also happens just once.
Test raid10 availability as a target feature (instead of doing
it in all the places where raid10 should be checked).
TODO: activation needs runtime validation - so metadata with raid10
are skipped from activation in user-friendly way in lvm2.
Parsing vg structure during supend/commit/resume may require a lot of
memory - so move this into vg_write.
FIXME: there are now multiple cache layers which our doing some thing
multiple times at different levels. Moreover there is now different
caching path with and without lvmetad - this should be unified
and both path should use same mechanism.
Remove 'skip' argument passed into the function.
We always used '0' - as this is the only supported
option (-K) and there is no complementary option.
Also add some testing for behaviour of skipping.
We already have /dev/disk/by-id/dm-uuid-... (which encompasses the
VG UUID and LV UUID in case of LVs since the mapping's UUID is
VG+LV UUID together) and /dev/disk/by-id/dm-name-... (which encompasses
the VG and LV name in case of LVs).
This patch addds /dev/disk/by-id/lvm-pv-uuid-<PV_UUID> that completes
this scheme and makes navigation a bit easier using PV UUIDs since
one can navigate using PV UUIDs only and there's no need to do extra
PV UUID <--> kernel name matching (the PV UUID is stable across reboots).
This may come in handy in various scripts.
Since we already have the PV UUID stored in udev database (as a result
of blkid call - returned in ID_FS_UUID blkid's variable), this operation
is very cheap indeed, just creating the extra one symlink.
There are typically 2 functions for the more advanced segment types that
deal with parameters in lvcreate.c: _get_*_params() and _check_*_params().
(Not all segment types name their functions according to this scheme.)
The former function is responsible for reading parameters before the VG
has been read. The latter is for sanity checking and possibly setting
parameters after the VG has been read.
This patch adds a _check_raid_parameters() function that will determine
if the user has specified 'stripe' or 'mirror' parameters. If not, the
proper number is computed from the list of PVs the user has supplied or
the number that are available in the VG. Now that _check_raid_parameters()
is available, we move the check for proper number of stripes from
_get_* to _check_*.
This gives the user the ability to create RAID LVs as follows:
# 5-device RAID5, 4-data, 1-parity (i.e. implicit '-i 4')
~> lvcreate --type raid5 -L 100G -n lv vg /dev/sd[abcde]1
# 5-device RAID6, 3-data, 2-parity (i.e. implicit '-i 3')
~> lvcreate --type raid6 -L 100G -n lv vg /dev/sd[abcde]1
# If 5 PVs in VG, 4-data, 1-parity RAID5
~> lvcreate --type raid5 -L 100G -n lv vg
Considerations:
This patch only affects RAID. It might also be useful to apply this to
the 'stripe' segment type. LVM RAID may include RAID0 at some point in
the future and the implicit stripes would apply there. It would be odd
to have RAID0 be able to auto-determine the stripe count while 'stripe'
could not.
The only draw-back of this patch that I can see is that there might be
less error checking. Rather than informing the user that they forgot
to supply an argument (e.g. '-i'), the value would be computed and it
may differ from what the user actually wanted. I don't see this as a
problem, because the user can check the device count after creation
and remove the LV if they have made an error.
When clustered VG is available in the system but we don't have
clustering set up for whatever reason, the lvm2-monitor scripts should
not fail completely just because these clustered VGs are skipped during
vgs/vgchange calls in lvm2-monitor initscript/systemd unit.
When the activation units are generated if use_lvmetad=0 (no
autoactivation), use --ignoreskippedcluster option for vgchange calls
since the cluster with cLVM is set up by separate units.
This avoids a situation in which the generated activation units are
improperly in failed state just because of the vgchange return value
when clustered VGs are encountered while the activation of non-clustered
VGs does proceed normally.
lv_active_change will enforce proper activation.
Modification of activation was wrong and lead to misuse of
autoactivation. Fix allows to use proper local exclusive activation,
while the removed code turned this into just exclusive
activation (losing required local property).
lvm2_cluster_activation_red_hat.service.in -> lvm2_cluster_activation_systemd_red_hat.service.in
lvm2_clvmd_red_hat.service.in -> lvm2_clvmd_red_hat.service.in
Edit lvm2-cluster-activation reference on cmirror - take new
lvm2-cmirrord.service, it was just cmirrord(.service) before
as the old initscript was used in compatibility mode.
Also, use WantedBy=multi-user.target instead of sysinit.target
in lvm2-cluster-activation.service.
The commit splits original clvmd service in two new native services
for systemd enabled systems while original init scripts remain unaltered.
New systemd native services:
1) clvmd daemon itself (lvm2_clvmd_red_hat.service.in)
2) (de)activation of clustered VGs (lvm2_cluster_activation_red_hat.service.in)
There're several reasons to split it. First, there's no support for conditional
stop in systemd and AFAIK they don't plan to support it. In other words:
if the deactivation fails for some reason, systemd doesn't care and will simply
kill all remaining processes in original cgroup (by default). Killing the
remaining procs can be suppressed however it doesn't solve the following problem:
You can't repeat the stop command of a failed service. The repeated stop command
is simply not propagated to the service in a failed state. You would have to start
and then try to stop the service again. Unfortunately, this can't be done while
the daemon is still running (and we need the daemon to stay active until all
clustered VGs are deactivated properly).
In a separated setup we need only to restart the failed activation service and
that's fine.
No need to fork lvmetad when running under systemd.
Also, the "lvmetad -R" support has been removed in lvm2 v2.02.98
so remove the ExecReload line that called it on "systemctl reload".
The libblkid can detect DM_snapshot_cow signature and when creating
new LVs with blkid wiping used (allocation/use_blkid_wiping=1 lvm.conf
setting and --wipe y used at the same time - which it is by default).
Do not issue any prompts about this signature when new LV is created
and just wipe it right away without asking questions. Still keep the
log in verbose mode though.
Avoid use of external origin with size unaligned/incompatible with
thin pool chunk size, since the last chunk is not correctly provisioned
when it is overwritten.
Avoid starting conversion of the LV to the thin pool and thin volume
at the same time. Since this is mostly a user mistake, do not try
to just convert to one of those type, since we cannot assume if the
user wanted LV to become thin volume or thin pool.
Before the fix tool reported pretty strange internal error:
Internal error: Referenced LV lvol1_tdata not listed in VG mvg.
Fixed output:
lvconvert --thinpool lvol0 -T mvg/lvol0
Can't use same LV mvg/lvol0 for thin pool and thin volume.
When lvm2 command forks, it calls reset_locking(),
which as an unwanted side effect unlinked lock file from filesystem.
Patch changes the behavior to just close locked file descriptor
in children - so the lock is being still properly hold in the parent.
Test LVM_LVMETAD_PIDFILE for pid for lvm command.
Fix WHATS_NEW envvar name usage
Fix init order in prepare_lvmetad to respect set vars
and avoid clash with system settings.
Update test to really test the 'is running' message.
Comparing for available feature missed the code path, when
maj is already bigger.
The bug would be only hit in the case, thin pool target would have
increased major version.
When thin volume is using external origin, current thin target
is not able to supply 'extended' size with empty pages.
lvm2 detects version and disables extension of LV past the external
origin size in this case.
Thin LV could be however still reduced and extended freely bellow
this size.
We need both offset and length when trying to wipe detected signatures.
The libblkid can fail so it's good to have an error message issued for
this state instead of being silent (libblkid does not issue any error
messages here). We just issued "stack" here before but that was not
quite useful if some error occurs...
Only flag thin LV for no scanning in udev if this LV is about
to be wiped. This happens only in case the thin LV's pool was not
created with zeroing of the new blocks enabled.
DO NOT USE LVMETAD IF YOU HAVE ANY LVM1-FORMATTED PVS.
You may continue to use it without lvmetad, but do please schedule
an upgrade to the lvm2 format (with 'vgconvert').
Sending the original LVM1 formatted metadata to lvmetad is breaking
assumptions made by the code, so I am marking the format as obsolete for
now and no longer sending it to lvmetad.
This means that if you are using lvmetad, lvm1 volumes will usually
appear invisible - though not always: it depends on exactly what
sequence of commands you run!
The current situation is not satisfactory.
We'll either fix lvmetad and reenable this or we'll fix the code to
issue appropriate warning messages when lvm1 PVs are encountered
to avoid accidents.
(The latest unfixed problem is that lvmetad assumes metadata sequence
numbers exist and always increase - but the lvm1 format does not define
or store any sequence number, confusing both the daemon and client
when default values get passed to-and-fro.)
If a PV in an existing VG becomes orphaned (with 'pvcreate -ff', for
example) the VG struct cached against its vginfo must be invalidated.
This is because the struct device it references no longer contains
the PV label so becomes incorrect.
This triggers the error:
Internal error: PV $dev unexpectedly not in cache.
when the PV from the cached VG metadata is subsequently looked up
in the cache.
Bug introduced in 2.02.87 by commit 7ad0d47c3c
("Cache and share generated VG structs").
Before:
lvm> pvs
PV VG Fmt Attr PSize PFree
/dev/loop3 vg12 lvm2 a-- 28.00m 28.00m
/dev/loop4 vg12 lvm2 a-- 28.00m 28.00m
lvm> pvcreate -ff /dev/loop3
Really INITIALIZE physical volume "/dev/loop3" of volume group "vg12" [y/n]? y
WARNING: Forcing physical volume creation on /dev/loop3 of volume group "vg12"
Physical volume "/dev/loop3" successfully created
lvm> pvs
Internal error: PV /dev/loop3 unexpectedly not in cache.
PV VG Fmt Attr PSize PFree
/dev/loop3 vg12 lvm2 a-- 28.00m 28.00m
/dev/loop3 lvm2 a-- 32.00m 32.00m
/dev/loop4 vg12 lvm2 a-- 28.00m 28.00m
After:
lvm> pvs
PV VG Fmt Attr PSize PFree
/dev/loop3 vg12 lvm2 a-- 28.00m 28.00m
/dev/loop4 vg12 lvm2 a-- 28.00m 28.00m
lvm> pvcreate -ff /dev/loop3
Really INITIALIZE physical volume "/dev/loop3" of volume group "vg12" [y/n]? y
WARNING: Forcing physical volume creation on /dev/loop3 of volume group "vg12"
Physical volume "/dev/loop3" successfully created
lvm> pvs
PV VG Fmt Attr PSize PFree
/dev/loop3 lvm2 a-- 32.00m 32.00m
/dev/loop4 vg12 lvm2 a-- 28.00m 28.00m
unknown device vg12 lvm2 a-m 28.00m 28.00m
When using filters for the pvscan --cache (the global_filter),
there's a difference between:
pvscan --cache -aay /dev/block/<major>:<minor>
and
pvscan --cache -aay <major>:<minor> (or --major <major> --minor <minor>)
In the first case, we need to be sure to have an exact matching line
in the filter for the device to be used, no aliases are considered
So for example even if we have accept rule for "/dev/sda" present,
this won't apply for "/dev/block/8:0" even though it's the same device!
This is because we're comparing the path used on command line directly
with the path written in the rule.
For the second one, any alias mentioned in the filter will apply
as we're comparing the major and minor pair, not looking at actual
device names - so any alias mentioned in the rules will suffice for
the filtering rule to apply.
For the global_filter to be properly used, we need to call the
second one in the lvm2-pvscan@.service - nobody is able to tell
what value of major:minor the kernel assignes next time, hence
this bug makes the use of global_filter quite unusable!
This reverts commit 24639be558.
Ok - seems we could be here a bit too active - and we
may remove devices which are unsuable for reasons we are not
aware of - thus taking down whole device could be way to big hammer.
So we still need some solution to recover from failing preload
and activation - but it needs more tunning.
When activation fails - we may leak large tree of partially loaded
devices in the dm table (i.e. failure in snapshot activation)
The best we can do here is try to deactivate whole device and
remove as much inactive table entries as we can.
When LV is scanned for its dependencies - scan also origin's snapshots,
and thin external origins.
So if any PV from snapshot or external origin device is missing - lvm2 will
avoid trying to activate such device.
When the device is inserted in dev_name_confirmed() stat() is
called twice as _insert() has it's own stat() call.
Extend _insert() parameter with struct stat* - which could be used
if it has been just obtained. When NULL is passed code is
doing its own stat() call as before.
Use internal type by default for thin provisioning.
If user is not interested in thin provisiong and doesn't
have thin provisining supporting tools installed,
configure will just print warning at the end of configure
process about limited support.
Boolean algebra changes for process_each_lv_in_vg().
1st.
Drop process_lv variable since it's not needed.
2nd.
process_lv was always initilized to 0 - so the condition was always true.
It the condition (!tags_supplied && !lvargs_supplied) evaluates as "true",
process_all is already set to 1, so skip vg tags evaluation.
3rd.
Move check for matching lv name in the front of lv tags check
since this check can't be skipped for lvargs_matched counter.
If this filter evaluates to true, skip lv tags evaluation.
Thin kernel target 1.9 still does not support online resize of
thin pool metadata properly - so disable it with expectation
for much higher version - and reenable after fixing kernel.
Since activation takes only read-lock, there could be
multiple activation running in parallel.
So instead of checking before taking any real lock,
let the locking resolve the problem and just
detect if the reason for failure has been remote
exlusive activation.
It should be also faster, since each activation does
not need to do explicit lock query.
The PIE and RELRO compiler/linker options can be used to produce a code
some techniques applied that makes the code more immune to some attacks:
- PIE (Position Independent Executable). It can make use of the ASLR
(Address Space Layout Randomization) provided by kernel to avoid
static locations for .text regions of executables (this is the 'pie'
compiler and linker option)
- RELRO (Relocation Read-Only). This prevents overwrite attacks of
the GOT (Global Offset Table) and PLT (Procedure Lookup Table)
used for relocations by making it read-only after all relocations
are resolved (these are the 'relro' and 'now' linker options) -
hence all symbols are resolved at the very start so there's no
need for those tables to be writeable later.
These compiler/linker options are now used by default for daemons
if the compiler/linker supports it.
In the case we have a dir with multiple objects and for
an individual object file we need special define -
allow to define it without adding extra rules.
To ensure dmeventd.o compilation will use EXTRA_FLAGS:
CFLAGS_dmeventd.o += $(EXTRA_FLAGS)
Then it's better to use:
dmeventd.o: CFLAGS += $(EXTRA_FLAGS)
At the end of lvconvert --snapshot with an active origin, the origin
gets reloaded.
Commit 57c0f72b1d ("lvconvert: use
_reload_lv on more places") accidentally replaced this with a snapshot
LV reload (which does nothing because only the origin is active).
Make it easier to run a live lvmetad in debugging mode and
to avoid conflicts if multiple test instances need to be run
alongside a live one.
No longer require -s when -f is used: use built-in default.
Add -p to lvmetad to specify the pid file.
No longer disable pidfile if -f used to run in foreground.
If specified socket file appears to be genuine but stale, remove it
before use.
On error, only remove lvmetad socket file if created by the same
process. (Previous code removes socket even while a running instance
is using it!)
If using lv/vgchange --sysinit -aay and lvmetad is enabled, we'd like to
avoid the direct activation and rely on autoactivation instead so
it fits system initialization scripts.
But if we're calling lv/vgchange --sysinit -aay too early when even
lvmetad service is not started yet, we just need to do the direct
activation instead without printing any error messages (while
trying to connect to lvmetad and not finding its socket).
This patch adds two helper functions - "lvmetad_socket_present" and
"lvmetad_used" which can be used to check for this condition properly
and avoid these lvmetad connections when the socket is not present
(and hence lvmetad is not yet running).
Revert 4777eb6872 which put
target_present check into init_snapshot_merge(). However
this function is also used when parsing metadata. So we would
get this present test performed even when target is not really
needed. So move this target_present test directly into lvconvert.
Fix buggy usage of "" (empty string) as a numerical string
value used for sorting.
On intel 64b platform this was typically resolve
as 0xffffff0000000000 - which is already 'close' to
UINT64_MAX which is used for _minusone64.
On other platforms it might have been giving
different numbers depends on aligment of strings.
Use proper &_minusone64 for sorting value when the reported
value is NUM.
Note: each numerical value needs to be thought about if it needs
default value &_zero64 or &_minusone64 since for cases, were
value of zero is valid, sorting should not be mixing entries
together.
Add wrapper function for dm_report_field_set_value() which returns void
and return 1, so the code could be shorter.
Add wrapper function for percent display _field_set_percent().
There's a tiny race when suspending the device which is part
of the refresh because when suspend ioctl is performed, the
dm kernel driver executes (do_suspend and dm_suspend kernel fn):
step 1: a check whether the dev is already suspended and
if yes it returns success immediately as there's
nothing to do
step 2: it grabs the suspend lock
step 3: another check whether the dev is already suspended
and if found suspended, it exits with -EINVAL now
The race can occur in between step 1 and step 2. To prevent
premature autoactivation failure, we're using a simple retry
logic here before we fail completely. For a complete solution,
we need to fix the locking so there's no possibility for suspend
calls to interleave each other to cause this kind of race.
This is just a workaround. Remove it and replace it with proper
locking once we have that in!
Failures in the temporary mirror used when up-converting cause dmeventd
to issue 'lvconvert --repair' on the sub-LV, <lv_name>_mimagetmp_?. The
'lvconvert' command refuses to deal with this sub-LV outright - it
expects to be given the name of the top-level LV. So, just like we do
with mirrored logs, we strip-off the portion of the name that is not
the top-level LV and issue the command on the top-level LV instead.
This patch fixes mostly cluster behavior but also updates
non-cluster reaction where calls like 'lvchange -aln'
lead to incorrect errors for some segment types.
Fix the implicit activation rules where some segment types could
be activated only in exclusive mode in cluster.
lvm2 command was not preserver 'local' property and incorrectly
converted local activations in to plain exclusive, so the local
activation could have activate volumes exclusively, but remotely.
If the volume_list filters out volume from activation,
it is still success result for this function.
Change the error message back to verbose level.
Detect if the volume is active localy before zeroing,
so we report error a bit later for cases, where volume
could not be activated because it doesn't pass through volume
list (but user still could create volume when he disables
zeroing)
Correct return code of activate_lv_excl().
Function is not supposed to return activation state of
activated volume, but return code of the operation.
Since i.e. when activation filter is allowing to activate
volume on current system, it is still success even though
no volume is activated.
MD can directly create partition devices without a need to run
an extra kpartx or partprobe call. We need to react to this event in
a different way as for bare MD devices - we need to handle the ADD event
for KERNEL=="md[0-9]*p[0-9]*" kernel name and trigger the LVM scanning
to update lvmetad to trigger autoactivation and so on...
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1023250
There is a problem with the way mirrors have been designed to handle
failures that is resulting in stuck LVM processes and hung I/O. When
mirrors encounter a write failure, they block I/O and notify userspace
to reconfigure the mirror to remove failed devices. This process is
open to a couple races:
1) Any LVM process other than the one that is meant to deal with the
mirror failure can attempt to read the mirror, fail, and block other
LVM commands (including the repair command) from proceeding due to
holding a lock on the volume group.
2) If there are multiple mirrors that suffer a failure in the same
volume group, a repair can block while attempting to read the LVM
label from one mirror while trying to repair the other.
Mitigation of these races has been attempted by disallowing label reading
of mirrors that are either suspended or are indicated as blocking by
the kernel. While this has closed the window of opportunity for hitting
the above problems considerably, it hasn't closed it completely. This is
because it is still possible to start an LVM command, read the status of
the mirror as healthy, and then perform the read for the label at the
moment after a the failure is discovered by the kernel.
I can see two solutions to this problem:
1) Allow users to configure whether mirrors can be candidates for LVM
labels (i.e. whether PVs can be created on mirror LVs). If the user
chooses to allow label scanning of mirror LVs, it will be at the expense
of a possible hang in I/O or LVM processes.
2) Instrument a way to allow asynchronous label reading - allowing
blocked label reads to be ignored while continuing to process the LVM
command. This would action would allow LVM commands to continue even
though they would have otherwise blocked trying to read a mirror. They
can then release their lock and allow a repair command to commence. In
the event of #2 above, the repair command already in progress can continue
and repair the failed mirror.
This patch brings solution #1. If solution #2 is developed later on, the
configuration option created in #1 can be negated - allowing mirrors to
be scanned for labels by default once again.
Add LV_TEMPORARY flag for LVs with limited existence during command
execution. Such LVs are temporary in way that they need to be activated,
some action done and then removed immediately. Such LVs are just like
any normal LV - the only difference is that they are removed during
LVM command execution. This is also the case for LVs representing
future pool metadata spare LVs which we need to initialize by using
the usual LV before they are declared as pool metadata spare.
We can optimize some other parts like udev to do a better job if
it knows that the LV is temporary and any processing on it is just
useless.
This flag is orthogonal to LV_NOSCAN flag introduced recently
as LV_NOSCAN flag is primarily used to mark an LV for the scanning
to be avoided before the zeroing of the device happens. The LV_TEMPORARY
flag makes a difference between a full-fledged LV visible in the system
and the LV just used as a temporary overlay for some action that needs to
be done on underlying PVs.
For example: lvcreate --thinpool POOL --zero n -L 1G vg
- first, the usual LV is created to do a clean up for pool metadata
spare. The LV is activated, zeroed, deactivated.
- between "activated" and "zeroed" stage, the LV_NOSCAN flag is used
to avoid any scanning in udev
- betwen "zeroed" and "deactivated" stage, we need to avoid the WATCH
udev rule, but since the LV is just a usual LV, we can't make a
difference. The LV_TEMPORARY internal LV flag helps here. If we
create the LV with this flag, the DM_UDEV_DISABLE_DISK_RULES
and DM_UDEV_DISABLE_OTHER_RULES flag are set (just like as it is
with "invisible" and non-top-level LVs) - udev is directed to
skip WATCH rule use.
- if the LV_TEMPORARY flag was not used, there would normally be
a WATCH event generated once the LV is closed after "zeroed"
stage. This will make problems with immediated deactivation that
follows.
The blkdeactivate script iterates over the list of devices if they're
given as an argument and it tries to umount/deactivate them one by one.
This iteration failed to proceed if any of the umount/deactivation
was unsuccessful - there was a missing "shift" call to move to the
next argument (device) for processing. As a result of this, the same
device was tried again and again, causing an endless loop, never
proceeding to the next device given.
When using ENV{SYSTEMD_WANTS}=lvm2-pvscan@... to instantiate a service
for lvmetad scan when the new PV appears in the system, the service
is started and executed. However, to track device removal, we need
to bind it (the "BindsTo" systemd directive) to a certain .device
systemd unit.
In default systemd setup, the device is tracked by it's name and
sysfs path (there's normally a sysfs path .device systemd unit for
a device and then the device name .device unit as an alias for it).
Neither of these two is useful for lvmetad update as we need to bind
it to device's <major>:<minor> pair.
The /dev/block/<major>:<minor> is the essential symlink under /dev
that exists for each block device (created by default udev rules
provided by udev directly). So let's use this as an alias for
the device's .device unit as well by means of "ENV{SYSTEMD_ALIAS}"
declaration within udev rules which systemd understands (this will
create a new alias "dev-block-<major>:<minor>.device".
Then we can easily bind the "dev-block-<major>:<minor>" device
systemd unit with instantiated lvm2-pvscan@<major>:<minor>.service.
So once the device is removed from the systemd, the
lvm-pvscan@<major>:<minor>.service executes it's ExecStop action
(which in turn notifies lvmetad about the device being gone).
This completes the udev-systemd-lvmetad interaction then.
Before, pvscan recognized either:
pvscan --cache --major <major> --minor <minor>
or
pvscan --cache <DevicePath>
When the device is gone and we need to notify lvmetad about device
removal, only --major/--minor works as we can't translate DevicePath
into major/minor pair anymore. The device does not exist in the system
and we don't keep DevicePath index in lvmetad cache to make the
translation internally into original major/minor pair. It would be
useless to keep this index just for this one exact case.
There's nothing bad about using "--major <major> --minor <minor>",
but it makes our life a bit harder when trying to make an
interconnection with systemd units, mainly with instantiated services
where only one and only one arg can be passed (which is encoded in the
service name).
This patch tries to make this easier by adding support for recognizing
the "<major>:<minor>" as a shortcut for the longer form
"--major <major> --minor <minor>". The rule here is simple: if the argument
starts with "/", it's a DevicePath, otherwise it's a <major>:<minor> pair.
There is no point eating stderr for these commands. In fact the
redirect causes confusion and hurts dubugging.
Also reword an error message if the pvs command fails so as not be
certain that a device is not a PV. Coupled with removing the stderr
redirect this will improve the user experience in the face of errors.
The new lvm2-pvscan@.service is responsible for on-demand execution
of "pvscan --cache --activate ay" which causes lvmetad to be
updated and LVM activation done if the VG is complete.
Also, use udev-systemd mechanism to instantiate the job as the
lvm2-pvscan@$devnode.service on each newly appeared PV in the system.
This prevents the background job to be killed (that would happen
if it was directly forked from udev rule - this behaviour is seen
in recent versions of udev with the help of systemd that can track
detached processes - the detached process would still be in the same
cgroup).
To enable this official udev-systemd protocol for instantiating
background jobs, use new --enable-udev-systemd-background-jobs
configure switch (it's disabled by default). This option is highly
recommended wherever systemd is used!
Prohibit conversion of pool device with active thin volumes.
Properly restore active states only for active thin pool volume.
Use new LV_NOSCAN when converting volume into thin pool's metadata.
This patch reinstates the lv_info call to check for open count of
the LV we're removing/deactivating - this was changed with commit 125712b
some time ago and we relied on the ioctl retry logic deeper in the libdm
while calling the exact 'remove' ioctl.
However, there are still some situations in which it's still required to
check for open count before we do any 'remove' actions - this mainly
applies to LVs which consist of several sub LVs, like it is for
virtual snapshot devices.
The commit 1146691 fixed the issue with ordering of actions during
virtual snapshot removal while the snapshot is still open. But
the check for the open status of the snapshot is still prone to
marking the snapshot as in use with an immediate exit even though
this could be a temporary asynchronous open only, most notably
because of udev and its WATCH udev rule with accompanying scans
for the event which is asynchronous. The situation where this crops
up most often is when we're closing the LV that was open for read-write
and then calling lvremove immediately.
This patch reinstates the original lv_info call for the open status
of the LV in the lv_check_not_in_use fn that gets called before
we do any LV removal/deactivation. In addition to original logic,
this patch adds its own retry loop with a delay (25x0.2 seconds)
besides the existing ioctl retry loop.
Split image should have an out-of-sync attr ('I') - always. Even if
the RAID LV has not been written to since the LV was split off, it is
still not part of the group that makes up the RAID and is therefore
"out-of-sync".
Since the virtual snapshot has no reason to stay alive once we
detach related snapshot - deactivate whole thing in front of
snapshot removal - otherwice the code would get tricky for
support in cluster.
The correct full solution would require to have transactions
for libdm operations.
Also enable to the check for snapshot being opened prior
the origin deactivation, otherwise we could easily end
with the origin being deactivate, but snapshot still kept
active, desynchronizing locking state in cluster.
Recognize DM_SUBSYSTEM_UDEV_FLAG0 which for LVM is the "LVM_NOSCAN"
flag that causes the scanning to be skipped (mainly blkid) and
also directs all the foreign rules to be skipped as well.
Important thing here is that the "watch" udev rules is still set
as well as the /dev/disk/by-id content created (which does not
require any scanning to be done). Also, the flag is dropped on
any subsequent event and scanning done...
A common scenario is during new LV creation when we need to wipe the
newly created LV and avoid any udev scanning before this stage otherwise
it could cause the device (the LV) to be claimed by some other subsystem
for which there were stale metadata within LV data.
This patch adds possibility to mark the LV we're just about to wipe with
a flag that gets passed to udev via DM_COOKIE as a subsystem specific
flag - DM_SUBSYSTEM_UDEV_FLAG0 (in this case the subsystem is "LVM")
so LVM udev rules will take care of handling that.
Patch 562ad293fd introduced code regression
when LV was converted to a thin LV with external origin and at the same time,
conversion of LV to a thin pool has been requested.
(RHBZ: #997704)
data_lv needs to be assigned after test for external conversion find pool.
Accept --ignoreskippedcluster with pvs, vgs, lvs, pvdisplay, vgdisplay,
lvdisplay, vgchange and lvchange to avoid the 'Skipping clustered
VG' errors when requesting information about a clustered VG
without using clustered locking and still exit with success.
The messages can still be seen with -v.
lib/metadata/lv_manip.c:_sufficient_pes_free() was calculating the
required space for RAID allocations incorrectly due to double
accounting. This resulted in failure to allocate when available
space was tight.
When RAID data and metadata areas are allocated together, the total
amount is stored in ah->new_extents and ah->alloc_and_split_meta is
set. '_sufficient_pes_free' was adding the necessary metadata extents
to ah->new_extents without ever checking ah->alloc_and_split_meta.
This often led to double accounting of the metadata extents. This
patch checks 'ah->alloc_and_split_meta' to perform proper calculations
for RAID.
This error is only present in the function that checks for the needed
space, not in the functions that do the actual allocation.
Add allocation/thin_pool_chunk_size_calculation lvm.conf
option to select a method for calculating thin pool chunk
sizes and define two possible values - "default" and "performance".
A previous commit (b6bfddcd0a) which
was designed to prevent segfaults during lvextend when trying to
extend striped logical volumes forgot to include calculations for
RAID4/5/6 parity devices. This was causing the 'contiguous' and
'cling_by_tags' allocation policies to fail for RAID 4/5/6.
The solution is to remember that while we can compare
ah->area_count == prev_lvseg->area_count
for non-RAID, we should compare
(ah->area_count + ah->parity_count) == prev_lvseg->area_count
for a general solution.
lvmetad is not yet supported in clustered environment so
disable it automatically if using lvmconf --enable-cluster
and reset it to default value if using lvmconf --disable-cluster.
Also, add a few comments in lvm.conf about locking_type vs. use_lvmetad
if setting it for clustered environment.
