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Use lv_is_* macros throughout the code base, introducing
lv_is_pvmove, lv_is_locked, lv_is_converting and lv_is_merging.
lv_is_mirror_type no longer includes pvmove.
Fix rename operation for snapshot (cow) LV.
Only the snapshot's origin has the lock and by mistake suspend
and resume has been called for the snapshot LV.
This further made volumes unusable in cluster.
So instead of suspend and resuming list of LVs,
we need to just suspend and resume origin.
As the sequence write/suspend/commit/resume
is widely used in lvm2 code base - move it to
new lv_update_and_reload function.
Fixing problem, when user sets volume_list and excludes thin pools
from activation. In this case pool return 'success' for skipped activation.
We need to really check the volume it is actually active to properly
to remove queued pool messages. Otherwise the lvm2 and kernel
metadata started to go async since lvm2 believed, messages were submitted.
Add also better check for threshold when create a new thin volume.
In this case we require local activation of thin pool so we are able
to check pool fullness.
The 'lv_type' field name was a bit misleading. Better one is 'lv_role'
since this fields describes what's the actual use of the LV currently -
its 'role'.
Sort out the lvresize calculation code to handle size changes
specified as physical extents as well as logical extents
and to process mirror resizing and raid extensions correctly.
The 'approx alloc' option was masking the underlying problem.
When testing conversion sanity, we checked lv->status & MIRRORED
which encompasses both old mirrors and raid1 mirrors. But we need to
ban only the old mirrors here hence allow raid1 mirrors.
The maximum stripe size is equal to the volume group PE size. If that
size falls below the STRIPE_SIZE_MIN, the creation of RAID 4/5/6 volumes
becomes impossible. (The kernel will fail to load a RAID 4/5/6 mapping
table with a stripe size less than STRIPE_SIZE_MIN.) So, we report an
error if it is attempted.
This is very rare because reducing the PE size down that far limits the
size of the PV below that of modern devices.
The lv_layout and lv_type fields together help with LV identification.
We can do basic identification using the lv_attr field which provides
very condensed view. In contrast to that, the new lv_layout and lv_type
fields provide more detialed information on exact layout and type used
for LVs.
For top-level LVs which are pure types not combined with any
other LV types, the lv_layout value is equal to lv_type value.
For non-top-level LVs which may be combined with other types,
the lv_layout describes the underlying layout used, while the
lv_type describes the use/type/usage of the LV.
These two new fields are both string lists so selection (-S/--select)
criteria can be defined using the list operators easily:
[] for strict matching
{} for subset matching.
For example, let's consider this:
$ lvs -a -o name,vg_name,lv_attr,layout,type
LV VG Attr Layout Type
[lvol1_pmspare] vg ewi------- linear metadata,pool,spare
pool vg twi-a-tz-- pool,thin pool,thin
[pool_tdata] vg rwi-aor--- level10,raid data,pool,thin
[pool_tdata_rimage_0] vg iwi-aor--- linear image,raid
[pool_tdata_rimage_1] vg iwi-aor--- linear image,raid
[pool_tdata_rimage_2] vg iwi-aor--- linear image,raid
[pool_tdata_rimage_3] vg iwi-aor--- linear image,raid
[pool_tdata_rmeta_0] vg ewi-aor--- linear metadata,raid
[pool_tdata_rmeta_1] vg ewi-aor--- linear metadata,raid
[pool_tdata_rmeta_2] vg ewi-aor--- linear metadata,raid
[pool_tdata_rmeta_3] vg ewi-aor--- linear metadata,raid
[pool_tmeta] vg ewi-aor--- level1,raid metadata,pool,thin
[pool_tmeta_rimage_0] vg iwi-aor--- linear image,raid
[pool_tmeta_rimage_1] vg iwi-aor--- linear image,raid
[pool_tmeta_rmeta_0] vg ewi-aor--- linear metadata,raid
[pool_tmeta_rmeta_1] vg ewi-aor--- linear metadata,raid
thin_snap1 vg Vwi---tz-k thin snapshot,thin
thin_snap2 vg Vwi---tz-k thin snapshot,thin
thin_vol1 vg Vwi-a-tz-- thin thin
thin_vol2 vg Vwi-a-tz-- thin multiple,origin,thin
Which is a situation with thin pool, thin volumes and thin snapshots.
We can see internal 'pool_tdata' volume that makes up thin pool has
actually a level10 raid layout and the internal 'pool_tmeta' has
level1 raid layout. Also, we can see that 'thin_snap1' and 'thin_snap2'
are both thin snapshots while 'thin_vol1' is thin origin (having
multiple snapshots).
Such reporting scheme provides much better base for selection criteria
in addition to providing more detailed information, for example:
$ lvs -a -o name,vg_name,lv_attr,layout,type -S 'type=metadata'
LV VG Attr Layout Type
[lvol1_pmspare] vg ewi------- linear metadata,pool,spare
[pool_tdata_rmeta_0] vg ewi-aor--- linear metadata,raid
[pool_tdata_rmeta_1] vg ewi-aor--- linear metadata,raid
[pool_tdata_rmeta_2] vg ewi-aor--- linear metadata,raid
[pool_tdata_rmeta_3] vg ewi-aor--- linear metadata,raid
[pool_tmeta] vg ewi-aor--- level1,raid metadata,pool,thin
[pool_tmeta_rmeta_0] vg ewi-aor--- linear metadata,raid
[pool_tmeta_rmeta_1] vg ewi-aor--- linear metadata,raid
(selected all LVs which are related to metadata of any type)
lvs -a -o name,vg_name,lv_attr,layout,type -S 'type={metadata,thin}'
LV VG Attr Layout Type
[pool_tmeta] vg ewi-aor--- level1,raid metadata,pool,thin
(selected all LVs which hold metadata related to thin)
lvs -a -o name,vg_name,lv_attr,layout,type -S 'type={thin,snapshot}'
LV VG Attr Layout Type
thin_snap1 vg Vwi---tz-k thin snapshot,thin
thin_snap2 vg Vwi---tz-k thin snapshot,thin
(selected all LVs which are thin snapshots)
lvs -a -o name,vg_name,lv_attr,layout,type -S 'layout=raid'
LV VG Attr Layout Type
[pool_tdata] vg rwi-aor--- level10,raid data,pool,thin
[pool_tmeta] vg ewi-aor--- level1,raid metadata,pool,thin
(selected all LVs with raid layout, any raid layout)
lvs -a -o name,vg_name,lv_attr,layout,type -S 'layout={raid,level1}'
LV VG Attr Layout Type
[pool_tmeta] vg ewi-aor--- level1,raid metadata,pool,thin
(selected all LVs with raid level1 layout exactly)
And so on...
_pvcreate_check() has two missing requirements:
After refreshing filters there must be a rescan.
(Otherwise the persistent filter may remain empty.)
After wiping a signature, the filters must be refreshed.
(A device that was previously excluded by the filter due to
its signature might now need to be included.)
If several devices are added at once, the repeated scanning isn't
strictly needed, but we can address that later as part of the command
processing restructuring (by grouping the devices).
Replace the new pvcreate code added by commit
54685c20fc "filters: fix regression caused
by commit e80884cd080cad7e10be4588e3493b9000649426"
with this change to _pvcreate_check().
The filter refresh problem dates back to commit
acb4b5e4de "Fix pvcreate device check."
If using persistent filter and we're refreshing filters (just like we
do for pvcreate now after commit 54685c20fc),
we can't rely on getting the primary device of the partition from the cache
as such device could be already filtered by persistent filter and we get
a device cache lookup failure for such device.
For example:
$ lvm dumpconfig --type diff
devices {
obtain_device_list_from_udev=0
}
$lsblk /dev/sda
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 128M 0 disk
`-sda1 8:1 0 127M 0 part
$cat /etc/lvm/cache/.cache | grep sda
"/dev/sda1",
$pvcreate /dev/sda1
dev_is_mpath: failed to get device for 8:1
Physical volume "/dev/sda1" successfully created
The problematic part of the code called dev_cache_get_by_devt
to get the device for the device number supplied. Then the code
used dev_name(dev) to get the name which is then used in check
whether there's any mpath on top of this dev...
This patch uses sysfs to get the base name for the partition
instead, hence avoiding the device cache which is a correct
approach here.
The message "Cannot deactivate remotely exclusive device locally." makes
sense only for clustered LV. If the LV is non-clustered, then it's
always exclusive by definition and if it's already deactivated, this
message pops up inappropriately as those two conditions are met.
So issue the message only if the conditions are met AND we have clustered VG.
With cmirrord, we can do pvmove of clustered mirror. The code checking
suitability of LVs on the PV being moved issued a message if a mirror
LV was found and the VG was clustered. However, the actual pvmove did
work correctly.
The top-level mirror LV is actually skipped in the code since it's
always layered on top of internal LVs making up the mirror LV and for pvmove
we consider these internal devices only as they're actually layered on
top of concrete PVs then. But we don't need to issue any message here
about skipping the top-level mirror LV - it's misleading here.
Commit e80884cd08 tried to dump filters
for them to be reevaluated when creating a PV to avoid overwriting
any existing signature that may have been created after last
scan/filtering.
However, we need to call refresh_filters instead of
persistent_filter->dump since dump requires proper rescannig to fill
up the persistent filter again. However, this is true only for pvcreate
but not for vgcreate with PV creation where the scanning happens before
this PV creation and hence the next rescan (if not full scan), does not
fill the persistent filter.
Also, move refresh_filters so that it's called sooner and only for
pvcreate, vgcreate already calls lvmcache_label_scan(cmd, 2) which
then calls refresh_filters itself, so no need to reevaluate this again.
This caused the persistent filter (/etc/lvm/cache/.cache file) to be
wrong and contain only the PV just being processed with
vgcreate <vg_name> <pv_name_to_create>.
This regression caused other block devices to be filtered out in case
the vgcreate with PV creation was used and then the persistent filter
is used by any other LVM command afterwards.
Make lvresize -l+%FREE support approximate allocation.
Move existing "Reducing/Extending' message to verbose level
and change it to say 'up to' if approximate allocation is being used.
Replace it with a new message that gives the actual old and new size or
says 'unchanged'.
This is addendum to commit 2e82a070f3
which fixed these spurious messages that appeared after commit
651d5093ed ("avoid pv_read in
find_pv_by_name").
There was one more "not found" message issued in case the device
could not be found in device cache (commit 2e82a07 fixed this only
for PV lookup itself). But if we "allow_unformatted" for
find_pv_by_name, we should not issue this message even in case
the device can't be found in dev cache as we just need to know
whether there's a PV or not for the code to decide on next steps
and we don't want to issue any messages if either device itself
is not found or PV is not found.
For example, when we were creating a new PV (and so allow_unformatted = 1)
and the device had a signature on it which caused it to be filtered
by device filter (e.g. MD signature if md filtering is enabled),
or it was part of some other subsystem (e.g. multipath), this message
was issued on find_pv_by_name call which was misleading.
Also, remove misleading "stack" call in case find_pv_by_name
returns NULL in pvcreate_check - any error state is reported
later by pvcreate_check code so no need to "stack" here.
There's one more and proper check to issue "not found" message if
the device can't be found in device cache within pvcreate_check fn
so this situation is still covered properly later in the code.
Before this patch (/dev/sda contains MD signature and is therefore filtered):
$ pvcreate /dev/sda
Physical volume /dev/sda not found
WARNING: linux_raid_member signature detected on /dev/sda at offset 4096. Wipe it? [y/n]:
With this patch applied:
$ pvcreate /dev/sda
WARNING: linux_raid_member signature detected on /dev/sda at offset 4096. Wipe it? [y/n]:
Non-existent devices are still caught properly:
$ pvcreate /dev/sdx
Device /dev/sdx not found (or ignored by filtering).
2.02.106 added suffixes to some LV uuids in the kernel.
If any of these LVs is activated with 2.02.105 or earlier,
and then a later version is used, the LVs appear invisible and
activation commands fail.
The code now has to check the kernel for both old and new uuids.
Fix get_pool_params to only read params.
Add poolmetadataspare option to get_pool_params.
Move all profile code into update_pool_params.
Move recalculate code into pool_manip.c
Major update of lvconvert code to handle cache and thin.
related targets.
Code tries to unify handling of cache and thin pools.
Better supports lvm2 syntax:
lvconvert --type cache --cachepool vg/pool vg/cache
lvconvert --type thin --thinpool vg/pool vg/extorg
lvconvert --type cache-pool vg/pool
lvconvert --type thin-pool vg/pool
as well as:
lvconvert --cache --cachepool vg/pool vg/cache
lvconvert --thin --thinpool vg/pool vg/extorg
lvconvert --cachepool vg/pool
lvconvert --thinpool vg/pool
While catching much more command line errors.
(Yet couple paths still needs more tests)
Detects as much cmdline errors prior opening VG.
Uses single lvconvert_name_params to convert LV names.
Detects as much incompatibilies in VG prior prompting.
Uses single prompt to confirm whole conversion.
TODO: still the code needs fixes...
Since the type passed LV is changed and content of data detroyed,
query user with prompt to confirm this operation.
Also add a proper wiping of header.
Using '--yes' will skip this prompt:
lvconvert -s --yes vg/lv vg/lvcow
Currently, we have two modes of activation, an unnamed nominal mode
(which I will refer to as "complete") and "partial" mode. The
"complete" mode requires that a volume group be 'complete' - that
is, no missing PVs. If there are any missing PVs, no affected LVs
are allowed to activate - even RAID LVs which might be able to
tolerate a failure. The "partial" mode allows anything to be
activated (or at least attempted). If a non-redundant LV is
missing a portion of its addressable space due to a device failure,
it will be replaced with an error target. RAID LVs will either
activate or fail to activate depending on how badly their
redundancy is compromised.
This patch adds a third option, "degraded" mode. This mode can
be selected via the '--activationmode {complete|degraded|partial}'
option to lvchange/vgchange. It can also be set in lvm.conf.
The "degraded" activation mode allows RAID LVs with a sufficient
level of redundancy to activate (e.g. a RAID5 LV with one device
failure, a RAID6 with two device failures, or RAID1 with n-1
failures). RAID LVs with too many device failures are not allowed
to activate - nor are any non-redundant LVs that may have been
affected. This patch also makes the "degraded" mode the default
activation mode.
The degraded activation mode does not yet work in a cluster. A
new cluster lock flag (LCK_DEGRADED_MODE) will need to be created
to make that work. Currently, there is limited space for this
extra flag and I am looking for possible solutions. One possible
solution is to usurp LCK_CONVERT, as it is not used. When the
locking_type is 3, the degraded mode flag simply gets dropped and
the old ("complete") behavior is exhibited.
lv_active_{locally,remotely,exclusively} display the original
"lv_active" field in a more separate way so that we can create
selection criteria in a binary-based form (yes/no).
Support remove of thin volumes With --force --force
when thin pools is damaged.
This way it's possible to remove thin pool with
unrepairable metadata without requiring to
manually edit lvm2 metadata.
lvremove -ff vg/pool
removes all thin volumes and pool even when
thin pool cannot be activated (to accept
removal of thin volumes in kernel metadata)
Use builddir not srcdir with make pofile.
Append 'incfile:' lines to %.d files to handle newly-missing dependencies
without 'make clean' after a file is moved or deleted.
Use suffixes for easier detection of private volumes.
This commit makes older volume UUIDs incompatible and
it most probably needs machine reboot after upgrade.
When creating pool's metadata - create initial LV for clearing with some
generic name and after the volume is create & cleared - rename it to
reserved name '_tmeta/_cmeta'.
We should not expose 'reserved' names for public LVs.
When repairing RAID LVs that have multiple PVs per image, allow
replacement images to be reallocated from the PVs that have not
failed in the image if there is sufficient space.
This allows for scenarios where a 2-way RAID1 is spread across 4 PVs,
where each image lives on two PVs but doesn't use the entire space
on any of them. If one PV fails and there is sufficient space on the
remaining PV in the image, the image can be reallocated on just the
remaining PV.
I've changed build_parallel_areas_from_lv to take a new parameter
that allows the caller to build parallel areas by LV vs by segment.
Previously, the function created a list of parallel areas for each
segment in the given LV. When it came time for allocation, the
parallel areas were honored on a segment basis. This was problematic
for RAID because any new RAID image must avoid being placed on any
PVs used by other images in the RAID. For example, if we have a
linear LV that has half its space on one PV and half on another, we
do not want an up-convert to use either of those PVs. It should
especially not wind up with the following, where the first portion
of one LV is paired up with the second portion of the other:
------PV1------- ------PV2-------
[ 2of2 image_1 ] [ 1of2 image_1 ]
[ 1of2 image_0 ] [ 2of2 image_0 ]
---------------- ----------------
Previously, it was possible for this to happen. The change makes
it so that the returned parallel areas list contains one "super"
segment (seg_pvs) with a list of all the PVs from every actual
segment in the given LV and covering the entire logical extent range.
This change allows RAID conversions to function properly when there
are existing images that contain multiple segments that span more
than one PV.
...to avoid using cached value (persistent filter) and therefore
not noticing any change made after last scan/filtering - the state
of the device may have changed, for example new signatures added.
$ lvm dumpconfig --type diff
allocation {
use_blkid_wiping=0
}
devices {
obtain_device_list_from_udev=0
}
$ cat /etc/lvm/cache/.cache | grep sda
$ vgscan
Reading all physical volumes. This may take a while...
Found volume group "fedora" using metadata type lvm2
$ cat /etc/lvm/cache/.cache | grep sda
"/dev/sda",
$ parted /dev/sda mklabel gpt
Information: You may need to update /etc/fstab.
$ parted /dev/sda print
Model: QEMU QEMU HARDDISK (scsi)
Disk /dev/sda: 134MB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags:
Number Start End Size File system Name Flags
$ cat /etc/lvm/cache/.cache | grep sda
"/dev/sda",
====
Before this patch:
$ pvcreate /dev/sda
Physical volume "/dev/sda" successfully created
With this patch applied:
$ pvcreate /dev/sda
Physical volume /dev/sda not found
Device /dev/sda not found (or ignored by filtering).
Take a local file lock to prevent concurrent activation/deactivation of LVs.
Thin/cache types and an extension for cluster support are excluded for
now.
'lvchange -ay $lv' and 'lvchange -an $lv' should no longer cause trouble
if issued concurrently: the new lock should make sure they
activate/deactivate $lv one-after-the-other, instead of overlapping.
(If anyone wants to experiment with the cluster patch, please get in touch.)
pvmove can be used to move single LVs by name or multiple LVs that
lie within the specified PV range (e.g. /dev/sdb1:0-1000). When
moving more than one LV, the portions of those LVs that are in the
range to be moved are added to a new temporary pvmove LV. The LVs
then point to the range in the pvmove LV, rather than the PV
range.
Example 1:
We have two LVs in this example. After they were
created, the first LV was grown, yeilding two segments
in LV1. So, there are two LVs with a total of three
segments.
Before pvmove:
--------- --------- ---------
| LV1s0 | | LV2s0 | | LV1s1 |
--------- --------- ---------
| | |
-------------------------------------
PV | 000 - 255 | 256 - 511 | 512 - 767 |
-------------------------------------
After pvmove inserts the temporary pvmove LV:
--------- --------- ---------
| LV1s0 | | LV2s0 | | LV1s1 |
--------- --------- ---------
| | |
-------------------------------------
pvmove0 | seg 0 | seg 1 | seg 2 |
-------------------------------------
| | |
-------------------------------------
PV | 000 - 255 | 256 - 511 | 512 - 767 |
-------------------------------------
Each of the affected LV segments now point to a
range of blocks in the pvmove LV, which purposefully
corresponds to the segments moved from the original
LVs into the temporary pvmove LV.
The current implementation goes on from here to mirror the temporary
pvmove LV by segment. Further, as the pvmove LV is activated, only
one of its segments is actually mirrored (i.e. "moving") at a time.
The rest are either complete or not addressed yet. If the pvmove
is aborted, those segments that are completed will remain on the
destination and those that are not yet addressed or in the process
of moving will stay on the source PV. Thus, it is possible to have
a partially completed move - some LVs (or certain segments of LVs)
on the source PV and some on the destination.
Example 2:
What 'example 1' might look if it was half-way
through the move.
--------- --------- ---------
| LV1s0 | | LV2s0 | | LV1s1 |
--------- --------- ---------
| | |
-------------------------------------
pvmove0 | seg 0 | seg 1 | seg 2 |
-------------------------------------
| | |
| -------------------------
source PV | | 256 - 511 | 512 - 767 |
| -------------------------
| ||
-------------------------
dest PV | 000 - 255 | 256 - 511 |
-------------------------
This update allows the user to specify that they would like the
pvmove mirror created "by LV" rather than "by segment". That is,
the pvmove LV becomes an image in an encapsulating mirror along
with the allocated copy image.
Example 3:
A pvmove that is performed "by LV" rather than "by segment".
--------- ---------
| LV1s0 | | LV2s0 |
--------- ---------
| |
-------------------------
pvmove0 | * LV-level mirror * |
-------------------------
/ \
pvmove_mimage0 / pvmove_mimage1
------------------------- -------------------------
| seg 0 | seg 1 | | seg 0 | seg 1 |
------------------------- -------------------------
| | | |
------------------------- -------------------------
| 000 - 255 | 256 - 511 | | 000 - 255 | 256 - 511 |
------------------------- -------------------------
source PV dest PV
The thing that differentiates a pvmove done in this way and a simple
"up-convert" from linear to mirror is the preservation of the
distinct segments. A normal up-convert would simply allocate the
necessary space with no regard for segment boundaries. The pvmove
operation must preserve the segments because they are the critical
boundary between the segments of the LVs being moved. So, when the
pvmove copy image is allocated, all corresponding segments must be
allocated. The code that merges ajoining segments that are part of
the same LV when the metadata is written must also be avoided in
this case. This method of mirroring is unique enough to warrant its
own definitional macro, MIRROR_BY_SEGMENTED_LV. This joins the two
existing macros: MIRROR_BY_SEG (for original pvmove) and MIRROR_BY_LV
(for user created mirrors).
The advantages of performing pvmove in this way is that all of the
LVs affected can be moved together. It is an all-or-nothing approach
that leaves all LV segments on the source PV if the move is aborted.
Additionally, a mirror log can be used (in the future) to provide tracking
of progress; allowing the copy to continue where it left off in the event
there is a deactivation.
Let's use the size of origin as the real base for percenta calculation,
and 'silenly' add needed metadata space for snapshot.
So now command 'lvcreate -s -l100%ORIGIN vg/lv' should always create a
snapshot to handle full device overwrite.
When creating a cache LV with a RAID origin, we need to ensure that
the sub-LVs of that origin properly change their names to include
the "_corig" extention of the top-level LV. We do this by first
performing a 'lv_rename_update' before making the call to
'insert_layer_for_lv'.
The thin-generic.profile contains settings for thin/thin pool volumes
suitable for generic environment/use containing default settings.
This allows users to change the global lvm.conf settings at will
and still keep the original settings for volumes that have this
thin profile assigned already.
Internal reporting function cannot handle NULL reporting value,
so ensure there is at least dummy label.
So move dummy_lable from tools/reporter.c and use it for all
report_object() calls in lib/report/report.c.
(Fixes RHBZ 1108394)
Simlify lvm_report_object initialization.
Enable 'retry' deactivation also in 'cleanup' phase.
It shouldn't be mostly needed - however udev now produces
more and more completelny non-synchronizable device opens,
so even for orphan devices we can't easily predict where
udevd opens devices.
So it's more preferable here to log error about device being open
and retry clean, but let the command proceed.
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.
The corosync cluster interface for clvmd did not correctly
deal with node up/down events so that when a node was removed
from the cluster clvmd would prevent remote operations
from happening, as it thought the node was up but not
running clvmd.
This patch fixes that code by simplifying the case to node
being up or down - which was the original intention
and is supported by pacemaker and CPG in the higher layers.
Signed-off-by: Christine Caulfield <ccaulfie@redhat.com>
When NULL info struct is passed in - function is usable
as a quick query for lv_is_active_locally() - with a bonus
we may query for layered device.
So it could be seen as a more efficient lv_is_active_locally().
Add internal devtypes reporting command to display built-in recognised
block device types. (The output does not include any additional
types added by a configuration file.)
> lvm devtypes -o help
Device Types Fields
-------------------
devtype_all - All fields in this section.
devtype_name - Name of Device Type exactly as it appears in /proc/devices.
devtype_max_partitions - Maximum number of partitions. (How many device minor numbers get reserved for each device.)
devtype_description - Description of Device Type.
> lvm devtypes
DevType MaxParts Description
aoe 16 ATA over Ethernet
ataraid 16 ATA Raid
bcache 1 bcache block device cache
blkext 1 Extended device partitions
...
The lvm2-activation-net.service was ordered only with respect to iscsi
and fcoe service before. In addition to that, we also need ordering
with respect to lvm2-activation.service to prevent parallel vgchange -aay
runs which may cause some problems during activation.
See also https://bugs.gentoo.org/show_bug.cgi?id=480066.
With this patch, the ordering is firmly set to:
lvm2-activation-early.service -> lvm2-activation.service -> lvm2-activation-net.service
Thanks to Alexander Tsoy for the original patch (modified a bit here):
https://www.redhat.com/archives/lvm-devel/2013-September/msg00049.html
Add more 'realistic' simulation of dlm locking.
Previous version was not capable to maintain multiple locks.
Current version doesn't handle multiqueues for locks,
so the ordering is different.
The same corner cases that exist for snapshots on mirrors exist for
any logical volume layered on top of mirror. (One example is when
a mirror image fails and a non-repair LVM command is the first to
detect it via label reading. In this case, the LVM command will hang
and prevent the necessary LVM repair command from running.) When
a better alternative exists, it makes no sense to allow a new target
to stack on mirrors as a new feature. Since, RAID is now capable of
running EX in a cluster and thin is not active-active aware, it makes
sense to pair these two rather than mirror+thinpool.
As further background, here are some additional comments that I made
when addressing a bug related to mirror+thinpool:
(https://bugzilla.redhat.com/show_bug.cgi?id=919604#c9)
I am going to disallow thin* on top of mirror logical volumes.
Users will have to use the "raid1" segment type if they want this.
This bug has come down to a choice between:
1) Disallowing thin-LVs from being used as PVs.
2) Disallowing thinpools on top of mirrors.
The problem is that the code in dev_manager.c:device_is_usable() is unable
to tell whether there is a mirror device lower in the stack from the device
being checked. Pretty much anything layered on top of a mirror will suffer
from this problem. (Snapshots are a good example of this; and option #1
above has been chosen to deal with them. This can also be seen in
dev_manager.c:device_is_usable().) When a mirror failure occurs, the
kernel blocks all I/O to it. If there is an LVM command that comes along
to do the repair (or a different operation that requires label reading), it
would normally avoid the mirror when it sees that it is blocked. However,
if there is a snapshot or a thin-LV that is on a mirror, the above code
will not detect the mirror underneath and will issue label reading I/O.
This causes the command to hang.
Choosing #1 would mean that thin-LVs could never be used as PVs - even if
they are stacked on something other than mirrors.
Choosing #2 means that thinpools can never be placed on mirrors. This is
probably better than we think, since it is preferred that people use the
"raid1" segment type in the first place. However, RAID* cannot currently
be used in a cluster volume group - even in EX-only mode. Thus, a complete
solution for option #2 must include the ability to activate RAID logical
volumes (and perform RAID operations) in a cluster volume group. I've
already begun working on this.
Creation, deletion, [de]activation, repair, conversion, scrubbing
and changing operations are all now available for RAID LVs in a
cluster - provided that they are activated exclusively.
The code has been changed to ensure that no LV or sub-LV activation
is attempted cluster-wide. This includes the often overlooked
operations of activating metadata areas for the brief time it takes
to clear them. Additionally, some 'resume_lv' operations were
replaced with 'activate_lv_excl_local' when sub-LVs were promoted
to top-level LVs for removal, clearing or extraction. This was
necessary because it forces the appropriate renaming actions the
occur via resume in the single-machine case, but won't happen in
a cluster due to the necessity of acquiring a lock first.
The *raid* tests have been updated to allow testing in a cluster.
For the most part, this meant creating devices with '-aey' if they
were to be converted to RAID. (RAID requires the converting LV to
be EX because it is a condition of activation for the RAID LV in
a cluster.)
Properly skip unmonitoring of thin pool volume in deactivation code
path. Code makes sure if there is just any thin pool user
it stays monitored with all its resources.
When the pool is created from non-linear target the more complex rules
have to be used and stacking needs to properly decode args for _tdata
LV. Also proper allocation policies are being used according to those
set in lvm2 metadata for data and metadata LVs.
Also properly check for active pool and extra code to active it
temporarily.
With this fix it's now possible to use:
lvcreate -L20 -m2 -n pool vg --alloc anywhere
lvcreate -L10 -m2 -n poolm vg --alloc anywhere
lvconvert --thinpool vg/pool --poolmetadata vg/poolm
lvresize -L+10 vg/pool
Udev daemon has recently introduced a limit on the number of udev
processes (there was no limit before). This causes a problem
when calling pvscan --cache -aay in lvmetad udev rules which
is supposed to activate the volumes. This activation is itself
synced with udev and so it waits for the activation to complete
before the pvscan finishes. The event processing can't continue
until this pvscan call is finished.
But if we're at the limit with the udev process count, we can't
instatiate any more udev processes, all such events are queued
and so we can't process the lvm activation event for which the
pvscan is waiting.
Then we're in a deadlock since the udev process with the
pvscan --cache -aay call waits for the lvm activation udev
processing to complete, but that will never happen as there's
this limit hit with the number of udev processes.
The process with pvscan --cache -aay actually times out eventually
(3min or 30sec, depends on the version of udev).
This patch makes it possible to run the pvscan --cache -aay
in the background so the udev processing can continue and hence
we can avoid the deadlock mentioned above.
The commit 82d83a01ce
"autoactivation: refresh existing VG before autoactivation"
causes problems (dangling udev_sync cookies, slow processing
of the pvscan --cache --major --minor call from udev rules)
when the autoactivation handler is run in parallel on
several PVs that belong to the same VG. Revert this patch
until the exact source of the problem is found and then
properly fixed and handled.
Remove default "/tmp" as destination directory if no args
specified for lvm2-activation-generator. Require all the
args to be specified directly for proper functionality.
The patch allows the user to also pvmove snapshots and origin logical
volumes. This means pvmove should be able to move all segment types.
I have, however, disallowed moving converting or merging logical volumes.
Top-level LVs (like RAID, mirror or thin) are ignored when determining which
portions of an LV to pvmove. If the user specified the name of an LV to
move and it was one of the above types, it would be skipped. The code would
never move on to check whether its sub-LVs needed moving because their names
did not match what the user specified.
The solution is to check whether a sub-LVs is part of the LV whose name was
specified by the user - not just if there was a name match.
This patch allows pvmove to operate on RAID, mirror and thin LVs.
The key component is the ability to avoid moving a RAID or mirror
sub-LV onto a PV that already has another RAID sub-LV on it.
(e.g. Avoid placing both images of a RAID1 LV on the same PV.)
Top-level LVs are processed to determine which PVs to avoid for
the sake of redundancy, while bottom-level LVs are processed
to determine which segments/extents to move.
This approach does have some drawbacks. By eliminating whole PVs
from the allocation list, we might miss the opportunity to perform
pvmove in some senarios. For example, if we have 3 devices and
a linear uses half of the first, a RAID1 uses half of the first and
half of the second, and a linear uses half of the third (FIGURE 1);
we should be able to pvmove the first device (FIGURE 2).
FIGURE 1:
[ linear ] [ -RAID- ] [ linear ]
[ -RAID- ] [ ] [ ]
FIGURE 2:
[ moved ] [ -RAID- ] [ linear ]
[ moved ] [ linear ] [ -RAID- ]
However, the approach we are using would eliminate the second
device from consideration and would leave us with too little space
for allocation. In these situations, the user does have the ability
to specify LVs and move them one at a time.
Do not print success status for lvm2-activation-generator:
"LVM: Activation generator successfully completed."
"LVM: Logical Volume autoactivation enabled." (if use_lvmetad=1)
Though this information is quite useful during boot, it may
be confusing for users if it happens anytime later and it
actually happens if systemd reloads. This is usually on package
update to update the systemd state and load any new units that are
newly installed in the system. The systemd reload is global and
so any existing generators are rerun at that moment too.
This is a regression caused by commit 3bd9048854.
The error message added with that commit "mpath major %d is not dm major %d" is
superfluous.
When scanning for mpath components, we're looking for a parent device.
But this parent device is not necessarily an mpath device (so the dm device)
if it exists - it can be any other device layered on top (e.g. an MD RAID device).
The bug addressed by this patch manifested itself during testing
by showing a mirror that never became 'in-sync' after creation.
The bug is isolated to distributions that do not have support
for openAIS checkpointing (i.e. > RHEL6, > F16).
When a node joins a group that is managing a mirror log, the other
machines in the group send it a checkpoint representing the current
state of the bitmap. More than one machine can send a checkpoint,
but only the initial one should be imported. Once the bitmap state
has been imported from the initial checkpoint, operations (such
as resync, mark, and clear operations) can begin. When subsequent
checkpoints are allowed to be imported, it has the effect of erasing
all the log operations between the initial checkpoint and the ones
that follow.
When cmirrord was updated to handle the absence of openAIS
checkpointing (commit 62e38da133),
the new import_checkpoint() function failed to honor the 'no_read'
parameter. This parameter was designed to avoid reading all but
the initial checkpoint. Honoring this parameter has solved the
issue of corrupting bitmap data with secondary checkpoints.
If loop device is first configured on systems where /dev/loop-control
is used to dynamically create the loop device itself, there's an
ADD+CHANGE even generated. But next time the existing /dev/loop[0-9]*
is reused, there's only a CHANGE event since the device representing
it is already present in kernel (so no ADD event in this case).
We can't ignore this CHANGE event for loop devices! This is a regression
caused by 756bcabbfe. We already had
a similar problem with MD devices which was fixed by
2ac217d408 (but that one was
only an intra-release fix).
When autoactivating a VG, there could be an existing VG with exactly
the same PV UUIDs. The PVs could be reappeared after previous
loss/disconnect (for example disconnecting and reconnecting iscsi).
Since there's no "autodeactivation" yet, the mappings for the LVs
from the VG were left in the system even if the device was disconnected.
These mappings also hold the major:minor of the underlying device.
So if the device reappears, it is assigned a different major:minor
pair (...and kernel name). We need to cope with this during
autoactivation so any existing mappings are corrected for any changes.
The VG refresh does that (the vgchange --refresh functionality) -
call this before VG autoactivation.
(If the VG does not exist yet, the VG refresh is NOP)
Split out the partitioned device filter that needs to open the device
and move the multipath filter in front of it.
When a device is multipathed, sending I/O to the underlying paths may
cause problems, the most obvious being I/O errors visible to lvm if a
path is down.
Revert the incorrect <backtrace> messages added when a device doesn't
pass a filter.
Log each filter initialisation to show sequence.
Avoid duplicate 'Using $device' debug messages.
Recent version of util-linux/umount (v2.23+) provides
umount --all-targets that can unmount all the mount targets of
the same device (the bind mounts). Use this if available when
calling the umount blkdeactivate.
Otherwise, for older versions of util-linux, use findmnt
(that is also a part of the util-linux) to iterate over all
mount targets of the same device - this is the manual way.
The blkdeactivate now suppresses error messages from external
tools that are called. Instead, only a summary message "done"
or "skipped" is issued by blkdeactivate as any error in calling
the external tool (e.g. unmounting or deactivating a device) causes
the device to be skipped and the blkdeactivate continues with the
next device in the tree.
Add new -e/--errors switch to display any error messages from
external tools.
Also, suppress any output given by the external tools and add
new -v/--verbose switch to display it including the verbose
output of the tools called (this will enable error reporting
as well).
Also add blkdeactivate -vv for even more debug (the script's debug).
84 files changed, 1540 insertions(+), 442 deletions(-)
Mostly bug fixes this time.
Also note:
md raid replaces dm mirroring as the default implementation.
Can call out to thin_repair to fix thin metadata.
Improved clvmd error detection/debugging information.
According to bug 995193, if a volume group
1) contains a mirror
2) is clustered
3) 'locking_type' = 0 is used
then it is not possible to remove the 'c'luster flag from the VG. This
is due to the way _lv_is_active behaves.
We shouldn't allow the cluster flag to be flipped unless the mirrors in
the cluster are not active. This is because different kernel modules
are used depending on whether a mirror is cluster or not. When we
attempt to see if the mirror is active, we first check locally. If it
is not, then we attempt to check for remotely active instances if the VG
is clustered. Since the no_lock locking type is LCK_CLUSTERED, but does
not implement 'query_resource', remote_lock_held will always return an
error in this case. An error from remove_lock_held is treated as though
the lock _is_ held (i.e. the LV is active remotely). This blocks the
cluster flag from changing.
The solution is to implement 'query_resource' for the no_lock type. It
will report a message and return 1. This will allow _lv_is_active to
function properly. The LV would be considered not active remotely and
the VG can change its flag.
1) Since the min|maxrecoveryrate args are size_kb_ARGs and they
are recorded (and sent to the kernel) in terms of kB/sec/disk,
we must back out the factor multiple done by size_kb_arg. This
is already performed by 'lvcreate' for these arguments.
2) Allow all RAID types, not just RAID1, to change these values.
3) Add min|maxrecoveryrate_ARG to the list of 'update_partial_unsafe'
commands so that lvchange will not complain about needing at
least one of a certain set of arguments and failing.
4) Add tests that check that these values can be set via lvchange
and lvcreate and that 'lvs' reports back the proper results.
gcc -O2 v4.8 on 32 bit architecture is causing a bug in parameter
passing. It does not happen with -01 nor -O0.
The problematic part of the code was strlen use in config.c in
the config_def_check fn and the call for _config_def_check_tree in it:
<snip>
rplen = strlen(rp);
if (!_config_def_check_tree(handle, vp, vp + strlen(vp), rp, rp + rplen, CFG_PATH_MAX_LEN - rplen, cn, cmd->cft_def_hash)) ...
</snip>
If compiled with -O0 (correct):
Breakpoint 1, config_def_check (cmd=0x819b050, handle=0x81a04f8) at config/config.c:775
(gdb) p vp
$1 = 0x8189ee0 <_cfg_path> "config"
(gdb) p strlen(vp)
$2 = 6
(gdb)
_config_def_check_tree (handle=0x81a04f8, vp=0x8189ee0 <_cfg_path>
"config", pvp=0x8189ee6 <_cfg_path+6> "", rp=0xbfffe1e8 "config",
prp=0xbfffe1ee "", buf_size=58, root=0x81a2568, ht=0x81a65
48) at config/config.c:680
(gdb) p vp
$4 = 0x8189ee0 <_cfg_path> "config"
(gdb) p pvp
$5 = 0x8189ee6 <_cfg_path+6> ""
If compiled with -O2 (incorrect):
Breakpoint 1, config_def_check (cmd=cmd@entry=0x8183050, handle=0x81884f8) at config/config.c:775
(gdb) p vp
$1 = 0x8172fc0 <_cfg_path> "config"
(gdb) p strlen(vp)
$2 = 6
(gdb) p vp + strlen(vp)
$3 = 0x8172fc6 <_cfg_path+6> ""
(gdb)
_config_def_check_tree (handle=handle@entry=0x81884f8, pvp=0x8172fc7
<_cfg_path+7> "host_list", rp=rp@entry=0xbffff190 "config",
prp=prp@entry=0xbffff196 "", buf_size=buf_size@entry=58, ht=0x
818e548, root=0x818a568, vp=0x8172fc0 <_cfg_path> "config") at
config/config.c:674
(gdb) p pvp
$4 = 0x8172fc7 <_cfg_path+7> "host_list"
The difference is in passing the "pvp" arg for _config_def_check_tree.
While in the correct case, the value of _cfg_path+6 is passed
(the result of vp + strlen(vp) - see the snippet of the code above),
in the incorrect case, this value is increased by 1 to _cfg_path+7,
hence totally malforming the string that is being processed.
This ends up with incorrect validation check and incorrect warning
messages are issued like:
"Configuration setting "config/checks" has invalid type. Found integer, expected section."
To workaround this issue, remove the "static" qualifier from the
"static char _cfg_path[CFG_PATH_MAX_LEN]". This causes the optimalizer
to be less aggressive (also shuffling the arg list for
_config_def_check_tree call helps).
If there is no RAID support in the kernel but the default mirror
segtype is "raid1", converting legacy mirrors can be problematic.
For example, changing the log type or converting a mirror to a linear
LV does not require the RAID modules to be present. However, because
lp->segtype is set to be RAID1 by the configuration file, the command
fails.
We should only be setting lp->segtype when converting mirrors if it is
going to change (e.g. to linear or between mirror types).
When creating a new thin pool and there's no profile requested
via "lvcreate --profile ...", inherit any VG profile if it's attached.
Currently this applies to these settings:
allocation/thin_pool_chunk_size
allocation/thin_pool_discards
allocation/thin_pool_zero
When creating a timeout thread for snapshots, the thread is not
tracked and thus never joined. This means that the exit status
of the timeout thread is held indefinitely. Saves a bit of
memory to set PTHREAD_CREATE_DETACHED when creating this thread.
I've also added pthread_attr_init|destroy to setup the creation
pthread_attr_t.
Reported-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Initial basic support for repair.
It currently takes pool metadata spare volume, which
is used for recovery. New spare is created if the volume
is successfuly repaired.
After the operation the previous _tmeta volume is moved
into _tmeta%d volume and if everything is ok, this volume
could be removed.
New _tmeta needs to be pvmoved to proper place and also
converted to i.e. mirror if it should be mirrored.
Later version will try to automate some steps here.
Add new configure lvm.conf options for binaries thin_repair
and thin_dump.
Those are part of device-mapper-persistent-data package
and will be used for recovery of thin_pool.
The PREFERRED allocation mechanism requires the number of areas in the
previous LV segment to match the number in the new segment being
allocated. If they do not match, the code may crash.
E.g. https://bugzilla.redhat.com/989347
Introduce A_AREA_COUNT_MATCHES and when not set avoid referring
to the previous segment with the contiguous and cling policies.
When using a global_filter and if this filter is incorrectly
specified, we ended up with a segfault:
raw/~ $ pvs
Invalid filter pattern "r|/dev/sda".
Segmentation fault (core dumped)
In the example above a closing '|' character is missing at the end
of the regex. The segfault itself was caused by trying to destroy
the same filter twice in _init_filters fn within the error path
(the "bad" goto target):
bad:
if (f3)
f3->destroy(f3);
if (f4)
f4->destroy(f4);
Where f3 is the composite filter (sysfs + regex + type + md + mpath filter)
and f4 is the persistent filter which encompasses this composite filter
within persistent filter's 'real' field in 'struct pfilter'.
So in the end, we need to destroy the persistent filter only as
this will also destroy any 'real' filter attached to it.
363 files changed, 19863 insertions(+), 9055 deletions(-)
This is a very large release - so expect bugs!
Please treat this release like a release candidate.
Changes to the external interfaces since 2.02.98 are not yet frozen.
Updated releases will follow quickly (days not weeks) as any problems
are handled.
The --type mirror requires -m/--mirrrors:
lvconvert --type mirror vg/lvol0
--type mirror requires -m/--mirrors
Run `lvconvert --help' for more information.
The --type raid* is allowed (the checks already existed):
lvconvert --type raid10 vg/lvol0
Converting the segment type for vg/lvol0 from linear to raid10 is not yet supported.
The --type snapshot is a synonym to -s/--snapshot:
lvconvert -s vg/lvol0 vg/lvol1
Logical volume lvol1 converted to snapshot.
lvconvert --type snapshot vg/lvol0 vg/lvol1
Logical volume lvol1 converted to snapshot.
All the other segment types are not supported, e.g.:
lvconvert --type zero vg/lvol0
Conversion using --type zero is not supported.
Run `lvconvert --help' for more information.
The status printed for dm-raid targets on older kernels does not include
the syncaction field. This is handled by dev_manager_raid_status() just
fine by populating the raid status structure with NULL for that field.
However, lv_raid_sync_action() does not properly handle that field being
NULL. So, check for it and return 0 if it is NULL.
Pool creation involves clearing of metadata device
which triggers udev watch rule we cannot udev synchronize with
in current code.
This metadata devices needs to be activated localy,
so in cluster mode deactivation and reactivation
is always needed.
However for non-clustered mode we may reload table
via suspend/resume path which avoids collision with
udev watch rule which was occasionaly triggering
retry deactivation loop.
Code has been also split into 2 separate code paths
for thin pools and thin volumes which improved readability
of the code as well.
Deactivation has been moved out of extend_pool() and
decision is now in _lv_create_an_lv() which knows
the change mode.
The new lvm2-activation-net.service activates LVM volumes
after network-attached devices are set up (iSCSI and FCoE)
if lvmetad is disabled and hence the autoactivation is not
used.
Created dlid for test is not needed afterward, so lower a memory
usage of this call is repeatedly used for building some large tree.
TODO: create function to use given buffer on stack as much cheaper.
Code needs to check if the layer origin device is suspended,
It's valid to create thinvolume snapshot of thinvolume which is also
used as an old-style snapshot. In this case we need to check -real
is suspended.
When adding origin_only - add only layer thin volume.
(in case it's also old-snapshot add only -real device)
Remove backup() call from update_pool_lv() as it's been there
duplicated and preperly order backup() call after lvresize,
so there is just one such call.
If the thin pool is known to be active, messages can be passed
to the pool even when the created thin volume is not going to be
activated.
So we do not need to stack large list of message and validate
and catch creation errors earlier in this case.
Replace the test for valid activation combination with simpler list of
deactivation combinations.
Normally, the lvm dumpconfig processes only the configuration tree
that is at the top of the cascade. Considering the cascade is:
CONFIG_STRING -> CONFIG_PROFILE -> CONFIG_MERGED_FILES/CONFIG_FILE
...then:
(dumpconfig of lvm.conf only)
raw/~ $ lvm dumpconfig allocation
allocation {
maximise_cling=1
mirror_logs_require_separate_pvs=0
thin_pool_metadata_require_separate_pvs=0
thin_pool_chunk_size=64
}
(dumpconfig of selected profile configuration only)
raw/~ $ lvm dumpconfig --profile test allocation
allocation {
thin_pool_chunk_size=8
thin_pool_discards="passdown"
thin_pool_zero=1
}
(dumpconfig of given --config configuration only)
raw/~ $ lvm dumpconfig --config 'allocation{thin_pool_chunk_size=16}' allocation
allocation {
thin_pool_chunk_size=16
}
The --mergedconfig option causes the configuration cascade to be
merged before processing it with dumpconfig:
(dumpconfig of merged selected profile and lvm.conf)
raw/~ $ lvm dumpconfig --profile test allocation --mergedconfig
allocation {
maximise_cling=1
thin_pool_zero=1
thin_pool_discards="passdown"
mirror_logs_require_separate_pvs=0
thin_pool_metadata_require_separate_pvs=0
thin_pool_chunk_size=8
}
(dumpconfig merged given --config and selected profile and lvm.conf)
raw/~ $ lvm dumpconfig --profile test --config 'allocation{thin_pool_chunk_size=16}' allocation --mergedconfig
allocation {
maximise_cling=1
thin_pool_zero=1
thin_pool_discards="passdown"
mirror_logs_require_separate_pvs=0
thin_pool_metadata_require_separate_pvs=0
thin_pool_chunk_size=16
}
Hence with the --mergedconfig, we are able to see the
configuration that is actually used when processing any
LVM command while using any combination of --config/--profile
options together with lvm.conf file.
Start separating the validation from the action in the basic lvresize
code moved to the library.
Remove incorrect use of command line error codes from lvresize library
functions. Move errors.h to tools directory to reinforce this,
exporting public versions of the error codes in lvm2cmd.h for dmeventd
plugins to use.
Document following items:
configuration cascade (man lvm.conf)
--profile ProfileName (man lvm)
--detachprofile (man vgchange/lvchange)
-o vg_profile/lv_profile (man vgs/lvs)
Also document --config a bit so we can see where it fits in the
configuration cascade - will be documented more in following commit...
Fix and improve handling on sigint.
Always check for signal presence *before* calling of command,
so it will not call the command when break was hit.
If the command has been finished succesfully there is
no problem to mark the command ok and not report interrupt at all.
Fix cuple related stack; reports and assignments.
Do not keep multiple archives for the executed command.
Reuse the ALLOCATABLE_PV from pv status for
ARCHIVED_VG vg status. Mark VG with the bit with the
first archivation.
If the user would upconvert a linear LV to a mirror without specifying
the segment type ("--type mirror" vs "--type raid1"), the "mirror"
segment type would be chosen without consulting the 'default_mirror_segtype'
setting in lvm.conf. This is now used as the basis for determining
which should be used if left unspecified.
Check for enough space in preallocated buffer.
Fixes problem, when lvm code started to suddenly allocate
too big memory chunks.
TODO: lvmetad protocol should announce needed size ahead,
so if metadata have 1MB we are not reallocating memory...
When vgname has not existed in metadata, it has crashed on double free
in format_instance destroy() - since VG was created, used FID and was
released - which also released FID, so further use was accessing bad
memory.
Fix it for this code path before release_vg() so FID will exists
when _vg_read_file_name() returns NULL.
