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Add A_PARTITION_BY_TAGS set when allocated areas should not share tags
with each other and allow _match_pv_tags to accept an alternative list
of tags. (Not used yet.)
Do not keep dangling LVs if they're removed from the vg->lvs list and
move them to vg->removed_lvs instead (this is actually similar to already
existing vg->removed_pvs list, just it's for LVs now).
Once we have this vg->removed_lvs list indexed so it's possible to
do lookups for LVs quickly, we can remove the LV_REMOVED flag as
that one won't be needed anymore - instead of checking the flag,
we can directly check the vg->removed_lvs list if the LV is present
there or not and to say if the LV is removed or not then. For now,
we don't have this index, but it may be implemented in the future.
This avoids a problem in which we're using selection on LV list - we
need to do the selection on initial state and not on any intermediary
state as we process LVs one by one - some of the relations among LVs
can be gone during this processing.
For example, processing one LV can cause the other LVs to lose the
relation to this LV and hence they're not selectable anymore with
the original selection criteria as it would be if we did selection
on inital state. A perfect example is with thin snapshots:
$ lvs -o lv_name,origin,layout,role vg
LV Origin Layout Role
lvol1 thin,sparse public,origin,thinorigin,multithinorigin
lvol2 lvol1 thin,sparse public,snapshot,thinsnapshot
lvol3 lvol1 thin,sparse public,snapshot,thinsnapshot
pool thin,pool private
$ lvremove -ff -S 'lv_name=lvol1 || origin=lvol1'
Logical volume "lvol1" successfully removed
The lvremove command above was supposed to remove lvol1 as well as
all its snapshots which have origin=lvol1. It failed to do so, because
once we removed the origin lvol1, the lvol2 and lvol3 which were
snapshots before are not snapshots anymore - the relations change
as we're processing these LVs one by one.
If we do the selection first and then execute any concrete actions on
these LVs (which is what this patch does), the behaviour is correct
then - the selection is done on the *initial state*:
$ lvremove -ff -S 'lv_name=lvol1 || origin=lvol1'
Logical volume "lvol1" successfully removed
Logical volume "lvol2" successfully removed
Logical volume "lvol3" successfully removed
Similarly for all the other situations in which relations among
LVs are being changed by processing the LVs one by one.
This patch also introduces LV_REMOVED internal LV status flag
to mark removed LVs so they're not processed further when we
iterate over collected list of LVs to be processed.
Previously, when we iterated directly over vg->lvs list to
process the LVs, we relied on the fact that once the LV is removed,
it is also removed from the vg->lvs list we're iterating over.
But that was incorrect as we shouldn't remove LVs from the list
during one iteration while we're iterating over that exact list
(dm_list_iterate_items safe can handle only one removal at
one iteration anyway, so it can't be used here).
cmirror uses the CPG library to pass messages around the cluster and maintain
its bitmaps. When a cluster mirror starts-up, it must send the current state
to any joining members - a checkpoint. When mirrors are large (or the region
size is small), the bitmap size can exceed the message limit of the CPG
library. When this happens, the CPG library returns CPG_ERR_TRY_AGAIN.
(This is also a bug in CPG, since the message will never be successfully sent.)
There is an outstanding bug (bug 682771) that is meant to lift this message
length restriction in CPG, but for now we work around the issue by increasing
the mirror region size. This limits the size of the bitmap and avoids any
issues we would otherwise have around checkpointing.
Since this issue only affects cluster mirrors, the region size adjustments
are only made on cluster mirrors. This patch handles cluster mirror issues
involving pvmove, lvconvert (from linear to mirror), and lvcreate. It also
ensures that when users convert a VG from single-machine to clustered, any
mirrors with too many regions (i.e. a bitmap that would be too large to
properly checkpoint) are trapped.
Dop unused value assignments.
Unknown is detected via other combination
(!linear && !striped).
Also change the log_error() message into a warning,
since the function is not really returning error,
but still keep the INTERNAL_ERROR.
Ret value is always set later.
Before, we refreshed filters and we did full rescan of devices if
we passed through wiping (wipe_known_signatures fn call). However,
this fn returns success even if no signatures were found and so
nothing was wiped. In this case, it's not necessary to do the
filter refresh/rescan of devices as nothing changed clearly.
This patch exports number of wiped signatures from all the
wiping functions below. The caller (_pvcreate_check) then checks
whether any wiping was done at all and if not, no refresh/rescan
is done, saving some time and resources.
for_each_sub_lv() now scans in depth also pools, however for
rename we actually do want to skip pools.
So add a new for_each_sub_lv_except_pools() to be used by rename,
every other user of for_each_sub_lv() scans every sub LV with pools
included.
This is i.e. necessary for properly working preload of pools
that are using raid arrays.
Support error_if_no_space feature for thin pools.
Report more info about thinpool status:
(out_of_data (D), metadata_read_only (M), failed (F) also as health
attribute.)
When creating cluster mirrors while they're not supposed to be activated
immediately after creation, we don't need to check for cmirrord availability.
We can just create these mirrors and let the check to be done on activation
later on. This is addendum for commit cba6186325.
When creating/activating clustered mirrors, we should have cmirrord
available and running. If it's not, we ended up with rather cryptic
errors like:
$ lvcreate -l1 -m1 --type mirror vg
Error locking on node 1: device-mapper: reload ioctl on failed: Invalid argument
Failed to activate new LV.
$ vgchange -ay vg
Error locking on node node 1: device-mapper: reload ioctl on failed: Invalid argument
This patch adds check for cmirror availability and it errors out
properly, also giving a more precise error messge so users are able
to identify the source of the problem easily:
$ lvcreate -l1 -m1 --type mirror vg
Shared cluster mirrors are not available.
$ vgchange -ay vg
Error locking on node 1: Shared cluster mirrors are not available.
Exclusively activated cluster mirror LVs are OK even without cmirrord:
$ vgchange -aey vg
1 logical volume(s) in volume group "vg" now active
Since we support device stack of pools over pool
(thin-pool with cache data volume) the existing code
is no longer able to detect orphan _pmspare.
So instead do a _pmspare check after volume removal,
and remove spare afterwards.
More efficient spare volume creation. Save 1 extra commit
and properly activate this volume according to our cluster
activation rules (using lv_active_change() for this).
Since we 'layer' for cache origin which and we support dropping
cache layer - we need to restore origin name in case
the origin LV is more complex target - i.e. raid.
Drop _corig from name
Cleanup and rename parent -> parent_lv.
Revert part of commit 51a29e6056,
it's probably bad idea to continue with any recovery, when
vg_write() or vg_commit() fail - so it's better to leave it as it is.
Let's use this function for more activations in the code.
'needs_exlusive' will enforce exlusive type for any given LV.
We may want to activate LV in exlusive mode, even when we know
the LV (as is) supports non-exlusive activation as well.
lvcreate -ay -> exclusive & local
lvcreate -aay -> exclusive & local
lvcreate -aly -> exclusive & local
lvcreate -aey -> exclusive (might be on any node).
Call check_new_thin_pool() to detect in-use thin-pool.
Save extra reactivation of thin-pool when thin pool is not active.
(it's now a bit more expensive to invoke thin_check for new pools.)
For new pools:
We now active locally exclusively thin-pool as 'public' LV.
Validate transaction_id is till 0.
Deactive.
Prepare create message for thin-pool and exclusively active pool.
Active new thin LV.
And deactivate thin pool if it used to be inactive.
Unlike with thin-pool - with cache we support all args also
directly when create cache volume.
So the result of 'separate' cache-pool creation and setting its
options should give same result as specifying those args
during cache creation.
Cache-pool values are used as defaults if the params are
not specified with cache creation.
Move code for creation of thin volume into a single place
out of lv_extend(). This allows to drop extra pool arg
for alloc_lv_segment() && lv_extend() and makes code
more easier to read and follow.
When we create volumes with chunk size bigger then extent size
we try to round up to some nearest chunk boundary.
Until now we did this for thins - use same logic for
cache volumes.
Refactor lvcreate code.
Prefer to use arg_outside_list_is_set() so we get automatic 'white-list'
validation of supported options with different segment types.
Drop used lp->cache, lp->cache and use seg_is_cache(), seg_is_thin()
Draw clear border where is the last moment we could change create
segment type.
When segment type is given with --type - do not allow it to be changed
later.
Put together tests related to individual segment types.
Finish cache conversion at proper part of lv_manip code after
the vg_metadata are written - so we could correcly clean-up created
stripe LV for cache volume.
We want to print smarter warning message only when
the zeroing was not provided on the first zeroable segment
of newly created LV.
Put warning within _should_wipe_lv function to avoid reevaluation
of same conditions twice.
Hide creation of temporary LVs and print them only in verbose mode.
e.g. hides confusing message about creation of _pmspare
device during creation of pool.
Instead of segtype->ops->name() introduce lvseg_name().
This also allows us to leave name() function 'empty' for default
return of segtype->name.
TODO: add functions for rest of ops->
When we are given an existing LV name - it needs to be allowed
to pass in even restricted name as the LV could have existed
long before we introduced some new restriction on prefix/suffix.i
Fix the regression on name limits and drop restriction to be applied
on any existing LVs - only the new created LV names have to be
complient with current name restrictions.
FIXME: we are currently using restricted names incorrectly in few
other places - device_is_usable() skips restricted names,
and udev flags are also incorrectly set for restricted names
so these LVs are not getting links properly.
Move code to better locations.
Improve test and remove invalid ones
(i.e. no reason to require cache size to be >= then origin).
Correctly comment where the code is doing actual conversion
of other existing volume - we do already a similar thing with
external origins.
Lots of new command line options and combinations is now supported.
Hopefully older syntax still works as well.
lvcreate --cache --cachepool vg/pool -l1
lvcreate --type cache --cachepool vg/pool -l1
lvcreate --type cache-pool vg/pool -l1
lvcreate --type cache-pool --name pool vg -l1
... and many many more ...
Since _pmspare is internal volume move it to
lv_remove_single - so it's automatically removed with
last remove thin-pool.
lv_remove_with_dependencies() is not always used for pool removal.
We are not using already defined segement type names where we could.
There is a lot of other places in device-mapper and LVM2 we have those
hardcoded so we should better finally have a common interface in
libdevmapper to avoid this.
Use of lv_info() internally in lv_check_not_in_use(),
so it always could use with_open_count properly.
Skip sysfs() testing in open_count == 0 case.
Accept just 'lv' pointer like other functions.
The function has 'built-in' lv_is_active_locally check,
which however is not what we need to check in many place.
For now at least remotely active snapshot merge is
detected and for this case merge on next activation is scheduled.
We use adjusted_mirror_region_size() in two different contexts.
Either on command line -
here we do want to inform user about reduction of size.
Or in pvmove activation context -
here we should only use 'verbose' info.
When requesting to reload an LV imrove this API to
automatically reload its lock holding LV as in cluster
only top-level LVs are addressable with lock.
Try to enforce consistent macro usage along these lines:
lv_is_mirror - mirror that uses the original dm-raid1 implementation
(segment type "mirror")
lv_is_mirror_type - also includes internal mirror image and log LVs
lv_is_raid - raid volume that uses the new dm-raid implementation
(segment type "raid")
lv_is_raid_type - also includes internal raid image / log / metadata LVs
lv_is_mirrored - LV is mirrored using either kernel implementation
(excludes non-mirror modes like raid5 etc.)
lv_is_pvmove - internal pvmove volume
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.
Use lv_update_and_reload() and lv_update_and_reload_origin()
to handle write/suspend/commit/resume sequence.
In few places this properly handle vg_revert() after suspend failure,
and also ensures there is metadata backup after successful vg_commit().
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.
This patch makes the keyword combinations found in "lv_layout" and
"lv_role" much more understandable - there were some ambiguities
for some of the combinations which lead to confusion before.
Now, the scheme used is:
LAYOUTS ("how the LV is laid out"):
===================================
[linear] (all segments have number of stripes = 1)
[striped] (all segments have number of stripes > 1)
[linear,striped] (mixed linear and striped)
raid (raid layout always reported together with raid level, raid layout == image + metadata LVs underneath that make up raid LV)
[raid,raid1]
[raid,raid10]
[raid,raid4]
[raid,raid5] (exact sublayout not specified during creation - default one used - raid5_ls)
[raid,raid5,raid5_ls]
[raid,raid5,raid6_rs]
[raid,raid5,raid5_la]
[raid,raid5,raid5_ra]
[raid6,raid] (exact sublayout not specified during creation - default one used - raid6_zr)
[raid,raid6,raid6_zr]
[raid,raid6,raid6_nc]
[raid,raid6,raid6_ns]
[mirror] (mirror layout == log + image LVs underneath that make up mirror LV)
thin (thin layout always reported together with sublayout)
[thin,sparse] (thin layout == allocated out of thin pool)
[thin,pool] (thin pool layout == data + metadata volumes underneath that make up thin pool LV, not supposed to be used for direct use!!!)
[cache] (cache layout == allocated out of cache pool in conjunction with cache origin)
[cache,pool] (cache pool layout == data + metadata volumes underneath that make up cache pool LV, not supposed to be used for direct use!!!)
[virtual] (virtual layout == not hitting disk underneath, currently this layout denotes only 'zero' device used for origin,thickorigin role)
[unknown] (either error state or missing recognition for such layout)
ROLES ("what's the purpose or use of the LV - what is its role"):
=================================================================
- each LV has either of these two roles at least: [public] (public LV that users may use freely to write their data to)
[public] (public LV that users may use freely to write their data to)
[private] (private LV that LVM maintains; not supposed to be directly used by user to write his data to)
- and then some special-purpose roles in addition to that:
[origin,thickorigin] (origin for thick-style snapshot; "thick" as opposed to "thin")
[origin,multithickorigin] (there are more than 2 thick-style snapshots for this origin)
[origin,thinorigin] (origin for thin snapshot)
[origin,multithinorigin] (there are more than 2 thin snapshots for this origin)
[origin,extorigin] (external origin for thin snapshot)
[origin,multiextoriginl (there are more than 2 thin snapshots using this external origin)
[origin,cacheorigin] (cache origin)
[snapshot,thicksnapshot] (thick-style snapshot; "thick" as opposed to "thin")
[snapshot,thinsnapshot] (thin-style snapshot)
[raid,metadata] (raid metadata LV)
[raid,image] (raid image LV)
[mirror,image] (mirror image LV)
[mirror,log] (mirror log LV)
[pvmove] (pvmove LV)
[thin,pool,data] (thin pool data LV)
[thin,pool,metadata] (thin pool metadata LV)
[cache,pool,data] (cache pool data LV)
[cache,pool,metadata] (cache pool metadata LV)
[pool,spare] (pool spare LV - common role of LV that makes it used for both thin and cache repairs)
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.
The lv_type_name function is remnant from old code that reported
only single string for the LV type. LV types are now reported
in a more extended way as keyword list that describe the type
precisely (using lv_layout_and_type fn).
The lv_type_name was used in some error messages to display the
type of the LV so just reinstate the old messages back referencing
the type directly with a string - this is enough for error messages.
They don't need to display the LV type as precisely as it's used
on lvs output (which is optimized for selection anyway).
$ lvs -a -o name,vg_name,attr,layout,type
LV VG Attr Layout Type
lvol0 vg -wI-a----- linear linear
[pvmove0] vg p-C-aom--- mirror mirror,pvmove
(added "mirror" for pvmove LV)
$ lvs -a -o name,vg_name,attr,layout,type
LV VG Attr Layout Type
lvol0 vg ori------- linear external,multiple,origin,thin
[lvol1_pmspare] vg ewi------- linear metadata,pool,spare
lvol2 vg Vwi-a-tz-- thin snapshot,thin
lvol3 vg Vwi-a-tz-- thin snapshot,thin
pool vg twi-a-tz-- pool,thin pool,thin
[pool_tdata] vg Twi-ao---- linear data,pool,thin
[pool_tmeta] vg ewi-ao---- linear metadata,pool,thin
(added "multiple" for external origin used for more than one
thin snapshot - lvol0 in the example above)
Thin snapshots having external origins missed the "snapshot" keyword for
lv_type field. Also, thin external origins which are thin devices (from
another pool) were not recognized properly.
For example, external origin itself can be either non-thin volume (lvol0
below) or it can be a thin volume from another pool (lvol3 below):
Before this patch:
$ lvs -o name,vg_name,attr,pool_lv,origin,layout,type
Internal error: Failed to properly detect layout and type for for LV vg/lvol3
Internal error: Failed to properly detect layout and type for for LV vg/lvol3
LV VG Attr Pool Origin Layout Type
lvol0 vg ori------- linear external,origin,thin
lvol2 vg Vwi-a-tz-- pool lvol0 thin thin
lvol3 vg ori---tz-- pool unknown external,origin,thin,thin
lvol4 vg Vwi-a-tz-- pool1 lvol3 thin thin
pool vg twi-a-tz-- pool,thin pool,thin
pool1 vg twi-a-tz-- pool,thin pool,thin
- lvol2 as well as lvol4 have missing "snapshot" in type field
- lvol3 has unrecognized layout (should be "thin"), but has double
"thin" in lv_type which is incorrect
- (also there's double "for" in the internal error message)
With this patch applied:
$ lvs -o name,vg_name,attr,pool_lv,origin,layout,type
LV VG Attr Pool Origin Layout Type
lvol0 vg ori------- linear external,origin,thin
lvol2 vg Vwi-a-tz-- pool lvol0 thin snapshot,thin
lvol3 vg ori---tz-- pool thin external,origin,thin
lvol4 vg Vwi-a-tz-- pool1 lvol3 thin snapshot,thin
pool vg twi-a-tz-- pool,thin pool,thin
pool1 vg twi-a-tz-- pool,thin pool,thin
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.
metadata/lv_manip.c:269: warning: declaration of "snapshot_count" shadows a global declaration
There's existing function called "snapshot_count" so rename the
variable to "snap_count".
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...
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'.
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
The get_lv_type_name helps with translating volume type
to human readable form (can be used in reports or
various messages if needed).
The lv_is_linear and lv_is_striped complete the set of
lv_is_* functions that identify exact volume types.
