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The same region size is used for both mirror volume and mirrored
log volume, but when the physical extent size is bigger than region size,
the size of mirror leg for mirrored log is smaller than the region size
and lvcreate command fails.
This patch adjusts a region size of mirrored log to a smaller value of
region size or physical extent size.
[This patch ensures that the region_size of the mirrored log does not
exceed the size of the mirrored log itself, which would violate the
kernel constraint: (region_size <= ti->len).]
Signed-off-by: Takahiro Yasui <takahiro.yasui@hds.com>
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
converting from 2-way to 3-way mirror (collapse_mirrored_lv)
was calling '_remove_mirror_images' with the 'remove_log'
parameter set. When the code was put in to fix 599898 to
honor log parameters during conversion, this argument was
suddenly being honored. Thus, when someone would convert from
a 2-way to 3-way mirror, the log would get removed.
'collapse_mirrored_lv' should not be calling '_remove_mirror_images'
with 'remove_log' set.
to 3-way mirror. When conversion operations are performed on
these types of mirrors, log options can be confused/ignored.
In the case of a converting 3-way mirror, we have a top-level
2-way corelog mirror whose legs are 1) a 2-way disk-log mirror
and 2) a linear device. If we wish to convert this 3-way mirror
to a 2-way mirror, the linear device is removed and the extra
top layer is eliminated. If we also wished to convert the disk
log to a core log in the same step, ambiguity creeps in. It is
somewhat obvious what the user wants - a 2-way mirror with a
corelog. However, looking at the top level mirror before
compression, it seems that the mirror already has a core log.
This is why the operation seemed to fail.
This patch simply re-evaluates what mirrored_seg points to after
a compression and then considers the log argument.
This is a fix for bug 599898.
Introduce struct cmd_vg to store information about needed
volume group name, vgid, flags and the pointer to opened VG.
Keep VGs list in alphabetical order for locking order.
Introduce functions:
cmd_vg_add() add new cmd_vg entry.
cmd_vg_lookup() search cmd_vgs for vg_name.
cmd_vg_read() open VGs in cmd_vgs list.
cmd_vg_release() close VGs in reversed order.
Add pointer to linked list of opened VGs. List temporarily keeps
the information about needed or locked and opened VGs for replicator target.
Also add cmd_missing_vgs flag information for quick check and
also for possible continuos process_each_lv() usage where we need
to detect whether failure has been caused by missing VG or
some other reason.
Adding configure.in support for Replicators.
Adding basic lib lvm support for Replicators.
Adding flags REPLICATOR and REPLICATOR_LOG.
Adding segments SEG_REPLICATOR and SEG_REPLICATOR_DEV.
Adding basic methods for handling replicator metadata.
Some commands start with a pvname, but we'd like to force users to
start with a vg handle to obtain a pv handle. Our best option seems
to be providing a way to look up the vgname from the pvname, and then
require them to use vg_read/vg_open.
In addition to the pvname lookup function, this patch also provides a
lookup by pvid. The lookup by pvid can be used in conjunction with
lvmcache_get_pvids to process all pvs in the system.
The pvid find function first calls lvmcache_vgname_from_pvid, which may
cause the label to be read if it is not in the cache. If the vgname is
returned is an orphan, we then check to see if there are metadata areas,
and if not, we scan every PV on the system by calling scan_vgs_for_pvs().
In most cases we should not need to do this, and by using the info->mdas
count, we avoid calling pv_read() as prior code did. So this patch is a
bit cleaner and should allow us to refactor more of the pv code.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
are active mirrors or snapshots.
We don't have the mechanisms in place to change the device-mapper
tables for those targets that have behavioral differences between
cluster and single machine instances. Allowing users to change
the attribute but not changing the target's behavior can lead to
data corruption.
The following bugs are fixed/avoided by this patch:
235123 - vgchange -c [ny] do not change target types when necessary
289331 - RFE: switching from cluster domain to local domain needs to deactivate volume somehow
289541 - when changing from local to cluster, volumes can not appear to be deactivated
being able to remove more images from a mirror than the
number of PVs directly specified for removal.
The effort to fix bug 581611 corrected a bug that was unnoticed
at the time. The loop in _remove_mirror_images that looks over
the specified PVs was allowing devices that were previously
counted and moved to the end of the list to be double-counted.
This resulted in the number of devices needed for removal always
being satisfied - even if the user did not specify enough PVs
for removal to satisfy the request. When 581611 was fixed, this
double-counting no longer took place and the result was to remove
only the minimum of the number of PVs specified or the number
that was asked to be removed.
By simply always setting 'new_area_count' (as used to be done
only in the else statement), we return to the previous behavior.
Indeed, this is exactly what the double-counting was allowing
to happen before the fix of 581611.
Allow lv_remove_with_dependencies() to know the top-level LV that was
requested to be removed (otherwise it recurses and we lose context).
A merging snapshot cannot be removed directly but the associated origin
can be. Disallow removal of a merging snapshot unless the associated
origin is also being removed.
We should write metadata into next position in the ring buffer while calling
vgrename and vgcfgrestore. At this code level (_vg_write_raw), we were not able
to determine if this is a rename or not. If yes, then accompanying VG structure
passed here has a new name set, not the old one.
When looking for a location where to put metadata next, we were given a NULL
value because of failed VG name comparison (in _find_vg_rlocn) between the
name in existing metadata and metadata we're just about to write.
This resets the position in the ring buffer, overwriting any existing metadata
(and also incorrectly updates the cache to "orphan" afterwards).
This patch just adds old_name item in struct volume_group that we can check and use
if necessary and detect renames at lower layers as well.
The same applies for vgcfgrestore, but here we're using a special value of
old_name, an empty string, to disable the check with existing metadata totally.
lvm2app needs a link back to the vg in order to use the vg handle for
memory allocations as well as other things. This patch adds the field
to struct physical_volume, and sets pv->vg when reading a vg from disk or
extending a vg by using the helper function previously added,
add_pvl_to_vgs(). Moves and renames are handled with separate code
inside move_pv() and vgmerge(). Add pv->vg check to vg_validate().
A NULL value in pv->vg signifies membership in the orphan VG.
Note though in the case of pv_read() on a device with metadatacopies == 0,
more devices may need to be read for an authoritative answer.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Now that we have library functions to add/delete a pv from the vg->pvs
list, call them from everywhere.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Add a delete function to manage the vg->pvs list.
NOTE: It may be possible to do further cleanup to these add/del functions
by passing a 'pv' as input instead of 'pv_list'. The pv_list is used for
functions which do allocations (lvcreate) while other places in the code
just manage a list of 'pv' (e.g. import functions, vgextend, etc).
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
A user specifying duplicate paths on the cmdline of vgcreate will
get a message similar to the following:
vgcreate vgtest2 /dev/loop3 /dev/loop5
Found duplicate PV jk1lXsKzwyOKlXq6bhaFFKMQQ06oPgu8: using /dev/loop5 not /dev/loop3
Found duplicate PV jk1lXsKzwyOKlXq6bhaFFKMQQ06oPgu8: using /dev/loop3 not /dev/loop5
Internal error: Duplicate PV id jk1lXs-Kzwy-OKlX-q6bh-aFFK-MQQ0-6oPgu8 detected for /dev/loop3 in vgtest2.
This is caught by vg_validate(), but it would be good to find
this condition earlier in the vgcreate code. add_pv_to_vg()
currently checks by pvname, but does not look for duplcate pvids.
This patch adds the check for duplicate pvids and results in new
error output as follows:
vgcreate vgtest2 /dev/loop3 /dev/loop5
Found duplicate PV jk1lXsKzwyOKlXq6bhaFFKMQQ06oPgu8: using /dev/loop5 not /dev/loop3
Found duplicate PV jk1lXsKzwyOKlXq6bhaFFKMQQ06oPgu8: using /dev/loop3 not /dev/loop5
Physical volume '/dev/loop5 (jk1lXs-Kzwy-OKlX-q6bh-aFFK-MQQ0-6oPgu8)' listed more than once.
Unable to add physical volume '/dev/loop5' to volume group 'vgtest2'.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
When moving parts of striped LVs, pvmove wouldn't care about leaving you with
two stripes on the same disk. Now --alloc anywhere is needed for that.
(Tried and gave up on two alternative approaches before the one committed here.)
Small refactor of main places in the code where a pv is added to a
vg into a small function which adds the pv to the list and updates
the vg counts.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
In add_pv_to_vg(), we should only add the pv to vg->pvs after all
internal checks have passed. The check for vg->extent_count exeeding
maximum was after we added the pv to the list, so this function could
return a state of vg->pvs that did not reflect other parameters such
as vg->pv_count.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Physical segments were still allocated from global
command context mempool.
This leads to very high memory usage when
activating large VG (vgchange).
(Memory usage was about 2G when >3000LVs).
Fix it by properly using vg->vgmem private pool,
so all the memory is released early.
New memory pool parameter is needed here for pv_split_segment
function.
Also fix the same problem in some minor allocations
(vg description, lv segment split).
In addition to previous patch, we really do not need
to search for segment which was just allocated in
split request.
Make pv_split_segment function return newly allocated
(split) segment also.
(So after this patch, there is only one user
of slow find_peg_by_pe).
The function find_peg_by_pe is incredibly inefficient
for Pvs with many segments.
In shiny future there should be binary (or interval) tree
instead of sorted linked list (volunteers?).
Anyway, for now, we can use dirty trick here to optimise this case:
- Allocations are usually applied from the beginning
of PV (we have no alloocation policy which allocates areas
"backwards")
- The only user of find_peg_by_pe is pv_split_segment()
call. In *most* cases it need to split *last* PV segment.
So if we search sorted pv segment list backwards, we
hit the requested segment immediatelly.
This patch applies this tiny change.
(and saves >30% of processing time when >3000LVs segments are on one PV!)
To discourage using this inefficient function from other code,
it is moved to pv_manip.c and used static for now:-)
This check-in enables the 'mirrored' log type. It can be specified
by using the '--mirrorlog' option as follows:
#> lvcreate -m1 --mirrorlog mirrored -L 5G -n lv vg
I've also included a couple updates to the testsuite. These updates
include tests for the new log type, and some fixes to some of the
*lvconvert* tests.
This is the next preparatory step towards better --alloc anywhere
support and is not intended to break anything that currently works so
please report any problems - segfaults, bogus data in the new debug
messages, or if the code now chooses bizarre allocation layouts.
. Add "monitoring" option to "activation" section of lvm.conf
. Have clvmd consult the lvm.conf "activation/monitoring" too.
. Introduce toollib.c:get_activation_monitoring_mode().
. Error out when both --monitor and --ignoremonitoring are provided.
. Add --monitor and --ignoremonitoring support to lvcreate. Update
lvcreate man page accordingly.
. Clarify that '--monitor' controls the start and stop of monitoring in
the {vg,lv}change man pages.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
When we pv_read() a device that has an orphan vgname, we might need to scan
the system to be sure this is true. However, if the PV has mdas, there's
no way possible for it to have an orphan vgname unless it is a true orphan.
Some areas of the code were optimized to take advantage of this fact, while
others were not (we would still do the expensive scan if a device had mdas
but had an orphan VG).
This patch unifies the code so that every place we are operating on such
a PV, we skip the expensive scan if there are mdas.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Acked-by: Petr Rockai <prockai@redhat.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
If user try to vgcreate or vgextend non-existent VG,
these messages appears:
# vgcreate xxx /dev/xxx
Internal error: Volume Group xxx was not unlocked
Device /dev/xxx not found (or ignored by filtering).
Unable to add physical volume '/dev/xxx' to volume group 'xxx'.
Internal error: Attempt to unlock unlocked VG xxx.
(the same with existing VG and non-existing PV & vgextend)
# vgextend vg_test /dev/xxx
...
It is caused because code tries to "refresh" cache if
md filter is switched on using cache destroy.
But we can change filters and rescan even without this
machinery now, just use refresh_filters
(and reset md filter afterwards).
(Patch also discovers cache alias bug in vgsplit test,
fix it by using better filter line.)
The kernel's blk_stack_limits() function may flag a device as
'misaligned'. If it does the alignment_offset will be -1.
Update set_pe_align_offset() to accommodate this corner case.
We need to allocate memory for the tag and copy the tag value before we
add it to the list of tags. We could put this inside lvm2app since the
tools keep their memory around until vg_write/vg_commit is called, but
we put it inside the internal library to minimize code in lvm2app.
We need to copy the tag passed in by the caller to ensure the lifetime of
the memory until the {vg|lv} handle is released.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Similar refactoring to vgchange - pull out common parts and put into
library function for reuse. Should be no functional change.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Pull out common code to be called from tools as well as lvm2app.
Leave archive() at tool level so we can use from vgcreate
as well as vgchange. Should be no functional change.
- add stack macro in vgchange
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Add a merging snapshot to the deptree, using the "error" target, rather
than avoid adding it entirely. This allows proper cleanup of the -cow
device without having to rename the -cow to use the origin's name as a
prefix.
Move the preloading of the origin LV, after a merge, from
lv_remove_single() to vg_remove_snapshot(). Having vg_remove_snapshot()
preload the origin allows the -cow device to be released so that it can
be removed via deactivate_lv(). lv_remove_single()'s deactivate_lv()
reliably removes the -cow device because the associated snapshot LV,
that is to be removed when a snapshot-merge completes, is always added
to the deptree (and kernel -- via "error" target).
Now when the snapshot LV is removed both the -cow and -real devices
get removed using uuid rather than device name. This paves the way
for us to switch over to info-by-uuid queries.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Internally we store sizes in sectors, but lvm2app exports sizes
in bytes. We could get fancier and allow units configuration but
this fix should do for now.
Fixes rhbz561422.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
where we should not expose internal VG names/uuids (the ones with "#" prefix )through the
interface. Otherwise, we could end up with library users opening internal VGs which will
initiate locking mechanism that won't be cleaned up properly.
"#orphans_{lvm1, lvm2, pool}" names are treated in a special way, they are truncated first
to "orphans" and this is used as a part of the lock name then (e.g. while calling lvm_vg_open()).
When library user calls lvm_vg_close(), the original name "orphans_{lvm1, lvm2, pool}"
is used directly and therefore no unlock occurs.
We should exclude internal VG names and uuids in the lists provided by lvmcache:
lvmcache_get_vgids() and lvmcache_get_vgnames().
All this seems to do is provide a memory leak so remove it.
The only caller of _alloc_pv() later explicitly sets
pv->vg_name = fmt->orphan_vg_name so clearly this allocation
should be removed. I also saw no where in the code where
strncpy was used to assign pv->vg_name - only direct assignments
and strdup's.
merge completes. This narrows the scope of this "hack" (which still
needs a proper fix within the deptree).
This stops dmeventd from trying to access snapshot devices that were
already removed.
Eliminate 'merging_snapshot' from 'struct logical_volume' and just use
'snapshot' for origin lv's reference to the merging snapshot; also set
MERGING in the origin lv's status.
snapshots are suspended, new origin is created, snapshots are resumed, new
origin is resumed. So it allocates memory while suspended.
To fix it, move vg_commit after suspend_lv, so that the suspend code will
treat it as precommitted vg and will preload new origin prior to suspend.
NOTE: agk doesn't like this "hack"; need to revisit and fix
Make 'merging_snapshot' pointer that points from the origin to the
segment that represents the merging snapshot.
Import/export 'merging_store' metadata.
Do not allow creating snapshots while another snapshot is merging.
Snapshot created in this state would certainly contain invalid data.
NOTE: patches at the end of this series will remove 'merging_snapshot'
and will introduce helpful wrappers and cleanups.
This spurious 'break' has been here since this code was first committed
in June 2005 and stopped the algorithm behaving as described in the
comment above it and rendered the variable 'already_found_one' useless.
1. Found bug in 'redundant log' implementation that caused
problems when converting a linear that spanned multiple
devices to a mirror (wasn't checking for NULL value of
provided parameter in _alloc_parallel_area)
2. Testsuite was failing to perform tests when 'not' modifier
was used. This allowed a couple issues to slip through.
Added a 'not_sh' modifier that negates tests performed by
functions defined in the shell source file.
3. Was initializing a variable to far down, which cause
previously set value to be overridden. (This was the
result of the collision of the "redundant log" and
lvconvert fix patches.)
It is pretty much the same as reducing the number of
mirror legs, but we just don't delete them afterwards.
The following command line interface is enforced:
prompt> lvconvert --splitmirror <n> -n <name> <VG>/<LV>
where 'n' is the number of images to split off, and
where 'name' is the name of the newly split off logical volume.
If more than one leg is split off, a new mirror will be the
result. The newly split off mirror will have a 'core' log.
Example:
[root@bp-01 LVM2]# !lvs
lvs -a -o name,copy_percent,devices
LV Copy% Devices
lv 100.00 lv_mimage_0(0),lv_mimage_1(0),lv_mimage_2(0),lv_mimage_3(0)
[lv_mimage_0] /dev/sdb1(0)
[lv_mimage_1] /dev/sdc1(0)
[lv_mimage_2] /dev/sdd1(0)
[lv_mimage_3] /dev/sde1(0)
[lv_mlog] /dev/sdi1(0)
[root@bp-01 LVM2]# lvconvert --splitmirrors 2 --name split vg/lv /dev/sd[ce]1
Logical volume lv converted.
[root@bp-01 LVM2]# !lvs
lvs -a -o name,copy_percent,devices
LV Copy% Devices
lv 100.00 lv_mimage_0(0),lv_mimage_2(0)
[lv_mimage_0] /dev/sdb1(0)
[lv_mimage_2] /dev/sdd1(0)
[lv_mlog] /dev/sdi1(0)
split 100.00 split_mimage_0(0),split_mimage_1(0)
[split_mimage_0] /dev/sde1(0)
[split_mimage_1] /dev/sdc1(0)
It can be seen that '--splitmirror <n>' is exactly the same
as '--mirrors -<n>' (note the minus sign), except there is the
additional notion to keep the image being detached from the
mirror instead of just throwing it away.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
This patch tries to correctly track changes in lvmcache related to commit/revert.
For vg_commit: if there is cached precommitted metadata, after successfull commit
these metadata must be tracked as committed.
For vg_revert: remote nodes must drop precommitted metadata and its flag in lvmcache.
(N.B. Patch do not touch LV locks here in any way.)
All this machinery is needed to properly solve remote node cache invalidaton which
cause several problems recently observed.
The use_precommitted flag indicates, that we want to use precommitted metadata
(used in suspend call to preload table with precommitted data).
But if there are no such data, committed metadata are read but the cache
still contains that precommitted flag.
(The problem is that later possible drop_metadata call will not invalidate
device in cache.)
The wrong precommitted state is stored in on remote nodes during normal
suspend/resume cycle _without_ vg_write/commit.
Use the PRECOMMITTED status flag here instead (which is always set if using
precommited metadata here).
If renaming snapshot with virtual origin, the origin is renamed too.
But the code must resume LVs in reverse order to properly
pair memlock (in cluster locking).
(The resume of snapshot resumes origin too and later resume
is ignored otherwise.)
When PV device reappears with old metadata, it is
always updated to new version byt atutomatic metadata
repair.
Remove missing flag if device is empty.
If device contains allocated extents, issue warning that
user must remove volumes and re-add this PV before
manipulating with this volume.
This partially solves bug 547842 when one PV (log) is failed,
dmeventd removes that device and later this device reappears and
is wrongly added into VG marked missing.
The memlock_inc() fix is wrong, memlock count is not
propagated to long living process (clvmd) and just
it underflow there.
Also suspend is needed to pre-load precommited metadata
on other nodes (remapping to error taget in this case).
With explicit suspend we generate lock request and code
can update memlock count.
(Infinitely "locked" memory caused that fs_unlock() was not
called properly and on cluster nodes remains
old links in /dev/mapper for not active devices.)
(N.B. failing of suspend call here is not handled as fatal
error - the LV is going to be removed later anyway.)
The new recovery code first tries to repair LV and then removes failed PV
from VG. It means that during operation there can be VG with PV missing,
and vg_read code handles it like not consistent VG.
We already allows returning "inconsistent" commited metadata,
for mirror repair we need this for precommited too.
(The suspend call prepares precommited metadata to inactive table on
other cluster nodes.)
"Inconsistent" here means - correct metadata, just with some metadata areas
not found (obviously on missing or failed PVs).
If there is problem deactivate LV and
_init_mirror_log is called with remove_on_failure = 1,
remove the newly created log LV from metadata.
(This can happen if there is active device with the same name
but different UUID.)
The main reason for this "workaround" patch is to
- do not keep _mlog volume in metadata, so user can repeat the action
- print better error message describing the real problem
# lvcreate -m 2 -n lv1 -l 1 --nosync vg_bar
WARNING: New mirror won't be synchronised. Don't read what you didn't write!
/dev/vg_bar/lv1_mlog: not found: device not cleared
Aborting. Failed to wipe mirror log.
Error locking on node bar-01: Input/output error
Unable to deactivate mirror log LV. Manual intervention required.
Failed to create mirror log.
# lvcreate -m 2 -n lv1 -l 1 --nosync vg_bar
WARNING: New mirror won't be synchronised. Don't read what you didn't write!
Aborting. Unable to deactivate mirror log.
Failed to initialise mirror log.
At this point they probably do not matter but going forward they
may - depends on future patches for replicator, etc. I think
these probably got missed because they were 'flags' so I changed
the name to 'status' to be consistent. So the on-disk
things 'flags' and the in structure 'status' (bits).
NOTE: WHATS_NEW already has entry for this in current release.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
The physical_volume, volume_group, logical_volume and lv_segment
structures' 'status' member is now uint64_t.
The alignment of these structures was also audited to remove holes. The
movement of some members in 'volume_group' and 'lv_segment' eliminates
holes. The 'physical_volume' structure still has one 4-byte hole after
'pe_size'; the other structures no longer have any holes. Each
structures' size has not changed.
Rename fill_default_pvcreate_params to pvcreate_params_set_defaults.
Rename pvcreate_validate_restore_params to pvcreate_restore_params_validate.
Rename pvcreate_validate_params to pvcreate_params_validate.
Similar to other vg_set_* functions, we create a vg_set_clustered() function
which does a few checks and sets a flag. This is where we check for
any limitations of clusters.
[root@xxxx-01 ~]# lvconvert -m 1 --corelog VG/cmirror
Unable to convert the log of inactive cluster mirror cmirror
I've tried to clean-up the message a little more, so the name
of the mirror stands out more while preserving the sense that
it's not a problem with the specific device, but the fact that
it is inactive that is causing the problem.
New msg:
Unable to convert the log of an inactive cluster mirror, cmirror
Split pvcreate_validate_params into recovery and non-recovery parameters.
This is necessary so we can call the non-recovery validate function from
vgextend / vgcreate. Note in the pvcreate tool case, we must call the
recovery validation function first (see treatment of pe_start and --zero),
and that we add a call to fill_default_pvcreate_params before the validation
functions.
We need defaults for pvcreate_params at a higher level - this will
allow us to use a common function from the tools to take defaults,
then fill in any non-defaults from the commandline.
Future patches will refactor vgcreate/vgextend to call this function
if one or more pvcreate parameters are given on the commandline.
Another refactoring for implicit pvcreate support. We need to get
the pvcreate parameters somehow to the vg_extend routine. Options
seemed to be:
1. Attach the parameters to struct volume_group. I personally
did not like this idea in most cases, though one could make an
agrument why it might be ok at least for some of the parameters
(e.g. metadatacopies).
2. Pass them in to the extend routine. This second route seemed
to be the best approach given the constraints.
Future patches will parse the command line and fill in the actual
values for the pvcreate_single call.
Should be no functional change.
Should be no functional change. If this parameter is set to NULL, just fail
the extend if the device is not already a PV. If non-NULL, try pvcreate_single
before failing. Note that pvcreate_single() handles the log_error in case
of failure so we just return 0 if pvcreate_single() fails.
Clean up VG_RESIZEABLE flag by creating vg_is_resizeable().
Update comment - we no longer have ALLOW_RESIZEABLE.
Also use vg_is_exported() in one place missed by earlier patch.
Should be no functional change.
Of the vgs field vg_attr, a few of the most likely to be used attributes
are clustered, exported, and partial. This patch adds the following 3
functions:
uint64_t lvm_vg_is_clustered(const vg_t vg)
uint64_t lvm_vg_is_exported(const vg_t vg)
uint64_t lvm_vg_is_partial(const vg_t vg)
Now that we've split vg_remove_single into two routines, in the first routine
that only manipulates memory, we move the PVs from the vg->pvs list to the
vg->removed_pvs list. Then later, we iterate through this list to write the
removed PVs to disk, which removes them from the volume group and places them
into the internal ORPHAN VG.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Author: Dave Wysochanski <dwysocha@redhat.com>
Split vg_remove_single into vg_remove_check (mandatory checks before
vgremove) and vg_remove (do actual remove by committing to disk).
In liblvm, we'd like to provide an consistent API that allows multiple
changes in memory, then let lvm_vg_write() control the commit to disk. In
some cases (for example, lvresize calls fsadm) this may not be possible.
However, since we are using an object model and dividing things into small
operations, the most logical model seems to be the lvm_vg_write model, and
handling the special cases as they arrive. So as best as possible
we move towards this end.
A possible optimization would be to consolidate vg_remove (committing)
code with vgreduce code. A second possible optimization is making vgreduce
of the last device equivalent to vgremove. Today, lvm_vg_reduce fails if
vgreduce is called with the last device, but from an object model perspective
we could view this as equivalent to vgremove and allow it. My gut feel is
we do not want to do this though.
Author: Dave Wysochanski <dwysocha@redhat.com>
Later patches should consolidate the vgremove / vgreduce functions but for
now let's clarify what vg_remove actually does by changing the name.
Author: Dave Wysochanski <dwysocha@redhat.com>
# pvcreate -u udwxr7-BoKY-EeKM-r033-xK6o-4og7-F13sGi /dev/sdc
uuid udwxr7BoKYEeKMr033xK6o4og7F13sGi|��� already in use on "/dev/sdb1"
is now
# pvcreate -u udwxr7-BoKY-EeKM-r033-xK6o-4og7-F13sGi /dev/sdc
uuid udwxr7-BoKY-EeKM-r033-xK6o-4og7-F13sGi already in use on "/dev/sdb1"
Adds 'data_alignment_detection' config option to the devices section of
lvm.conf. If your kernel provides topology information in sysfs (linux
>= 2.6.31) for the Physical Volume, the start of data area will be
aligned on a multiple of the ’minimum_io_size’ or ’optimal_io_size’
exposed in sysfs.
minimum_io_size is used if optimal_io_size is undefined (0). If both
md_chunk_alignment and data_alignment_detection are enabled the result
of data_alignment_detection is used.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If the pvcreate --dataalignmentoffset option is not specified the start
of a PV's aligned data area will be shifted by the associated
'alignment_offset' exposed in sysfs (unless
devices/data_alignment_offset_detection is disabled in lvm.conf).
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Adds pe_align_offset to 'struct physical_volume'; is initialized with
set_pe_align_offset(). After pe_start is established pe_align_offset is
added to it.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
For now, a simple way to enforce the read/write semantics is to just save the
open mode of the VG. If the caller uses lvm_vg_create, the mode is write.
The caller using lvm_vg_open can use either read or write to open the VG.
Once we have this, we enforce the permissions on each API call and don't allow
a caller to modify a VG that has not been opened properly.
This may be better combined with the locking mode, but I view that as future
cleanup, past this initial release. The intial release should enforce the
basic object semantics though, as described in the lvm.h file.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Adding the ability to get the seqno is important for an application to
determine if something has changed in a VG. Otherwise, the only way to
know is to open the VG with write permission and hold the handle.
This function behaves a little bit different than vg_reduce_single, because
it allowes to remove even the latest pv. This has been done to be consistent
to lvm_vg_create, which creates an empty vg.
removed_pvs has been added to the volume_group struct. vg_reduce adds remove
pvs to this list to be able to commit the changes for the pvs in lvm_vg_comm
in liblvm2app.
Initialize removed_pvs list in format-specific volume_group constructors.
Ideally, we should have a base constructor here that initializes the general
non-format specific members of struct volume_group. But until then, there
are multiple places to initialize these members. Maybe a better patch would
be a base constructor patch for struct volume_group. That is more work
though.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Thomas Woerner <twoerner@redhat.com>
Author: Dave Wysochanski <dwysocha@redhat.com>
For liblvm 'get' functions, we should share code with the reporting functions.
This means we need common code to return the values for the fields.
In this patch we refactor a few of the fields needed in liblvm.
Unfortunately, for the simple fields that do derefernces of structure
members (for example, vg_extent_count), we cannot call the common function
from the reporting infrastructure without more refactoring. The reason is
that the dereference of the simple fields is done deep inside the reporting
code (to get the generic "data" pointer), and the display function is a
generic 'size32' function. We can fix these issues later with more
refactoring.
Should be no functional change and the testsuite should cover any possible
regressions. The only fields in the report affected by this patch are:
vg_size, vg_free, and pv_mda_count.
Author: Dave Wysochanski <dwysocha@redhat.com>
After some refactorings, we can now move the bulk of _lvcreate into the
internal library, and we can call from liblvm. In the future, we should
refactor lv_create_single further, probably by segtype, to reduce the
size of struct lvcreate_params. For now this is a reasonable refactor
and allows us to re-use the function from liblvm.
Author: Dave Wysochanski <dwysocha@redhat.com>
The implicit pvcreate require either moving the ORPHAN_VG lock outside
pvcreate_single or somehow having the function know or detect whether
the ORPHAN_VG lock is already held.
Author: Dave Wysochanski <dwysocha@redhat.com>
Passing NULL for pvcreate parameters gives you default parameters for
pvcreate_single.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Author: Dave Wysochanski <dwysocha@redhat.com>
In preparation for implicit pvcreate during vgcreate / vgextend,
move bulk of pvcreate logic inside library.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Author: Dave Wysochanski <dwysocha@redhat.com>
We must hold the VG_ORPHAN lock until we commit to disk. Otherwise,
we risk a race condition on vgcreate / vgextend. Reverts the following
commit:
commit 72a41480ba
Author: Dave Wysochanski <dwysocha@redhat.com>
Date: Fri Jul 10 20:09:21 2009 +0000
Move orphan lock obtain/release inside vg_extend().
With this change we now have vgcreate/vgextend liblvm functions.
Note that this changes the lock order of the following functions as the
orphan lock is now obtained first. With our policy of non-blocking
second locks, this should not be a problem.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
These messages are unnecessary in the set functions. We check for this
condition and print a message in the vgchange tool but not the library
functions.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
When converting to the new liblvm functions, the vgcreate code path
changed to create a new vg, then set values. As a result of this
change, and the fact that we give a user a message if they try to
set the same value of a VG attribute (extent_size, alloc_policy, etc),
you'll see these 2 extraneous "is already" messages with vgcreate:
tools/lvm vgcreate vg2 /dev/loop2
Physical extent size of VG vg2 is already 4.00 MB
Volume group allocation policy is already normal
Volume group "vg2" successfully created
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Author: Dave Wysochanski <dwysocha@redhat.com>
We provide a lock type that behaves like no_locking, but is not
clustered. Moreover, it also forbids any write locks. This magically (and
consistently) prevents use of clustered VGs, or changing local VGs with
--ignorelockingfailure. As a bonus, we can remove the special hacks in a few
places. Of course, people looking for trouble can always set their locking_type
to 0 to override.
Define the 5 main liblvm objects to be the pv, vg, lv, lvseg, and pvseg.
We need handles defined to all these objects in order for liblvm to be
equivalent to the reporting commands pvs, vgs, and lvs.
- move vg_t, lv_t, and pv_t from metadata-exported.h into lvm.h
- move lv_segment and pv_segment forward declarations into lvm.h
- add lvseg_t and pvseg_t to lvm.h
NOTE: We currently have an inconsistency in handle definitions.
lvm_t is defined as a pointer, while these other handles are just
structures. We should pick one scheme and be consistent - perhaps
define all handles as pointers (this is what I've seen elsewhere).
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
The checks for RESIZEABLE_VG should now be inside the various functions that
have to do such operations.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Remove READ_REQUIRE_RESIZEABLE flag from vgsplit similar to the removal from
vgextend. Move the check inside the functions that actually move pvs from
one vg structure to another. Should be no functional change.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
In the future we may export these functions or something like them in liblvm
For now this helps in cleaning up the checks for RESIZEABLE since we can
use the internal library function vg_bad_status_bits.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Move the check for the RESIZEABLE flag inside the vg_extend function.
When we consolidated the vg locking, reading, and status flag checking,
we tied the check for the RESIZEABLE flag to the vg_read() call. The problem
with this is you cannot know what other APIs the application my or may not
call after a vg_read() call. Thus the READ_REQUIRE_RESIZEABLE flag is not
really ideal - ideally we should be checking for this flag on a specific
operation, not inside the vg_read() call. This patch moves one check inside
the library.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
With this change we now have vgcreate/vgextend liblvm functions.
Note that this changes the lock order of the following functions as the
orphan lock is now obtained first. With our policy of non-blocking
second locks, this should not be a problem.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Move the vg orphan lock inside vg_remove_single, now a complete liblvm
function. Note that this changes the order of the locks - originally
VG_ORPHAN was obtained first, then the vgname lock. With the current
policy of non-blocking second locks, this could mean we get a failure
obtaining the orphan lock. In the case of a vg with lvs being removed,
this could result in the lvs being removed but not the vg. Such a
scenario could have happened prior though with a different failure.
Other tools were examined for side-effects, and no major problems
were noted.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Move check for active LVs outside of library function. The vgremove
liblvm function function will fail if there are active LVs. It will
be the application's responsibility to check this condition and remove
the LVs individually before calling vgremove. Note also that we've
duplicated the EXPORTED_VG check in vgremove_single (tools) and
vg_remove_single (library). Duplication seemed the only option here
since we don't want to do the automatic removal of LVs (in the tools)
if the vg is exported, and we still need to protect the library call
from removal if the vg is exported.
We still need to deal with the ORPHAN lock but vg_remove_single is now
very close to our liblvm function.
TODO: Refactor lvremove in a similar way.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
vg_t *vg_create(struct cmd_context *cmd, const char *vg_name);
This is the first step towards the API called to create a VG.
Call vg_lock_newname() inside this function. Use _vg_make_handle()
where possible.
Now we have 2 ways to construct a volume group:
1) vg_read: Used when constructing an existing VG from disks
2) vg_create: Used when constructing a new VG
Both of these interfaces obtain a lock, and return a vg_t *.
The usage of _vg_make_handle() inside vg_create() doesn't fit
perfectly but it's ok for now. Needs some cleanup though and I've
noted "FIXME" in the code.
Add the new vg_create() plus vg 'set' functions for non-default
VG parameters in the following tools:
- vgcreate: Fairly straightforward refactoring. We just moved
vg_lock_newname inside vg_create so we check the return via
vg_read_error.
- vgsplit: The refactoring here is a bit more tricky. Originally
we called vg_lock_newname and depending on the error code, we either
read the existing vg or created the new one. Now vg_create()
calls vg_lock_newname, so we first try to create the VG. If this
fails with FAILED_EXIST, we can then do the vg_read. If the
create succeeds, we check the input parameters and set any new
values on the VG.
TODO in future patches:
1. The VG_ORPHAN lock needs some thought. We may want to treat
this as any other VG, and require the application to obtain a handle
and pass it to other API calls (for example, vg_extend). Or,
we may find that hiding the VG_ORPHAN lock inside other APIs is
the way to go. I thought of placing the VG_ORPHAN lock inside
vg_create() and tying it to the vg handle, but was not certain
this was the right approach.
2. Cleanup error paths. Integrate vg_read_error() with vg_create and
vg_read* error codes and/or the new error APIs.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
NOTE: vg_set_alloc_policy() returns success if you try to set a value that
is already stored. The behavior of vgchange is the same though - it fails.
There is a fixme noted in the code about this inconsistency, which should
be resolved if possible.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
In liblvm, we will reserve the word 'change' to mean an API that
both sets one or more values, and commits to disk. This will be
consistent with the LVM commandline. The existing vg_change_pesize()
function does not commit to disk, but just changes the extent_size
and ensures all internal structures are updated. This logic should
be contained in a function that sets the value.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
It would be nice to have one function that does all the validation
and setting of the VG's pesize. However, currently some checks
are in the higher-level function _vgchange_pesize(), and some
checks are in the lower function vg_change_pesize().
This patch moves most of the higher-level checks inside
vg_change_pesize. In one case a failure return code is
changed from ECMD_FAILED to EINVALID_CMD_LINE.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Remove unneeded LOCK_NONBLOCKING from vg_read() API and tools that
use it. We no longer need this flag anywhere since we now automatically
set LCK_NONBLOCK inside lock_vol() if vgs_locked().
For further details, see:
commit d52b3fd3fe
Author: Dave Wysochanski <dwysocha@redhat.com>
Date: Wed May 13 13:02:52 2009 +0000
Remove NON_BLOCKING lock flag from tools and set a policy to auto-set.
As a simplification to the tools and further liblvm, this patch pushes
the setting of NON_BLOCKING lock flag inside the lock_vol() call.
The policy we set is if any existing VGs are currently locked, we
set the NON_BLOCKING flag.
At some point it may make sense to add this flag back if we get an
RFE from a liblvm user, but for now let's keep it as simple as
possible.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Remove READ_CHECK_EXISTENCE and vg_might_exist().
This flag and API is no longer used now that we have a separate
API to check for existence.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Remove unneeded LOCK_KEEP from vg_read() interface.
Update comment to clarify cases where _vg_lock_and_read() may return
with an error but the lock held. Would be nice to make the vg_read()
interface consistent with regards to lock held and error behavior.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Sun May 3 13:06:14 CEST 2009 Petr Rockai <me@mornfall.net>
* Don't segfault in vg_release when vg->cmd is NULL.
Author: Petr Rockai <prockai@redhat.com>
Committer: Dave Wysochanski <dwysocha@redhat.com>
Sun May 3 12:32:30 CEST 2009 Petr Rockai <me@mornfall.net>
* Rework the toollib interface (process_each_*) on top of new vg_read.
Rebased 6/26/09 by Dave W.
- Add skipping message to process_each_lv
- Remove inconsistent_t.
status flag after reading the volume group. Thus, no need to set the flag
in vg_read() or clear it later before calling _vg_bad_status_bits().
Also, add back in the !lockingfailed() as part of the CLUSTERED flag check.
It's unclear why it was removed when the check was moved from
_vg_bad_status_bits() to inside _vg_lock_and_read().
There was an open question about the last check in the 'if' stmt for
lockingfailed() with a previous patch submitted. However, I would
defer that right now as it is a separate item and this patch should
be no functional change by including the !lockingfailed().
Petr acked this patch on 5/26 I just forgot to check it in.
Acked-by: Petr Rockai <prockai@redhat.com>
Various tools need to check for existence of a VG before doing something
(vgsplit, vgrename, vgcreate). Currently we don't have an interface to
check for existence, but the existence check is part of the vg_read* call(s).
This patch is an attempt to pull out some of that functionality into a
separate function, and hopefully simplify our vg_read interface, and
move those patches along.
vg_lock_newname() is only concerned about checking whether a vg exists in
the system. Unfortunately, we cannot just scan the system, but we must first
obtain a lock. Since we are reserving a vgname, we take a WRITE lock on
the vgname. Once obtained, we scan the system to ensure the name does
not exist. The return codes and behavior is in the function header.
You might think of this function as similar to an open() call with
O_CREAT and O_EXCL flags (returns failure with -EEXIST if file already
exists).
NOTE: I think including the word "lock" in the function name is important,
as it clearly states the function obtains a lock and makes the code more
readable, especially when it comes to cleanup / unlocking. The ultimate
function name is somewhat open for debate though so later we may rename.
Because preload of table for snapshot can produce snapshot
metadata (in kernel cow header) read.
Code should suspend origin first to avoid possible deadlock
when preloading (thus calling snapshot in-kernel constructor)
for origin with suspended cow device.
(fixes previous commit)
Several commands calls process_each_vg() and in provided
callback it explicitly recovers VG if inconsistent.
(vgchange, vgconvert, vgscan)
It means that old VG is released and reread but the function
above (process_one_vg) tries to unlock and release old VG.
Patch moves the repair logic into _process_one_vg() function.
It always tries to read vg (even inconsistent) and then decides
what to do according new defined parameter.
Also patch unifies inconsistent error messages.
The only slight change if for vgremove command, where
it now tries to repair VG before it removes if force arg is given.
(It works similar way before, just the order of operation changed).
When mirror convert polling is started (mainly as backgound process,
in lvchange -a y or in lvconvert itself) it tries to read VG
and LV identified by its name.
Unfortunatelly, the VG can have already different LV under the same name,
and various more or less funny things can happen (note that
_finish_lvconvert_mirror suspends the volume for example).
(the typical example is our testing script which continuously recreates
LVs under the same name in the same VG.)
This patch adds optional uuid parameter which helps to properly
select the monitoring object. For lvconvert polling it is set to LV UUID
and both _get_lvconvert_vg and _get_lvconvert_lv uses it to read proper VG/LV.
(In the pvmove case it is NULL, here we poll for physical volume name).
If there is no free area for log, code should break the loop.
(Otherwise it uses uninitializes areas later.)
Easily reproducible using lvconvert --repair
- kill device with log
- run lvconvert --repair vg/lv (with no PV usable for log)
During vgreduce is failed mirror image replaced with error segment,
this segmant type has always area_count == 0.
Current code expects that there is at least one area with device,
patch fixes it by additional check (fixes segfault during vgreduce).
Also do not calculate readahead in every lv_info call, we only need
to cache PV readahead before activation calls which locks memory.
When we are stacking LV over device, which has for some reason
increased read_ahead (e.g. MD RAID), the read_ahead hint
for libdevmapper is wrong (it is zero).
If the calculated read_ahead hint is zero, patch uses read_ahead of underlying device
(if first segment is PV) when setting DM_READ_AHEAD_MINIMUM_FLAG.
Because we are using dev-cache, it also store this value to cache for future use
(if several LVs are over one PV, BLKRAGET is called only once for underlying device.)
This should fix all the reamining problems with readahead mismatch reported
for DM over MD configurations (and similar cases).
We can temporarily violate max_lv during mirror conversion etc.
(If the operation fails, orphan mirror images are visible to administrator
for manual remove for example. Not that this should ever happen:-)
Force limit only for lvcreate (and vg merge) command.
Patch also adds simple max_lv tests into testsuite
The vg->lv_count parameter now includes always number of visible
logical volumes.
Note that virtual snapshot volume (snapshotX) is never visible,
but it is stored in metadata with visible flag.
link_lv_to_vg and unlink_lv_from_vg are the only functions
for adding/removing logical volume from volume group.
Only these function should manipulate with vg->lvs list.
The snapshot segment (snapshotX) is created twice
during the text metadata segment processing.
This can cause temporary violation of max_lv count.
Simplify the code, snapshot segment is properly initialized
in init_snapshot_seg function now and do not need to be replaced
by vg_add_snapshot call.
The vg_add_snapshot() is now usefull only for adding new
snapshot and it shares the same initialization function.
The snapshot name is always generated, name paramater can be
removed from function call.
The seg variable is temporary variable for list iterator,
code cannot expect that after iteration it remains NULL
(it contains non-NULL pointer here id list is empty).
Patch fixes first_seg function so it now correctly returns NULL
for empty segment list.
Add lvs origin_size field.
Fix linux configure --enable-debug to exclude -O2.
Still a few rough edges, but hopefully usable now:
lvcreate -s vg1 -L 100M --virtualoriginsize 1T
The backup() call store metadata from memory.
But in cluster backup() call performs
remote nodes metadata backup and it reads data from disk.
For metadata backup consistency,
patch moves all backup() calls after vg_commit.
(Moreover, some tools already do that this way.)
Since now, all code reading volume group is responsible for releasing
the memory allocated by calling vg_release(vg).
(For simplicity of use, vg_releae can be called for vg == NULL,
the same logic like free(NULL)).
Also providing simple macro for unlocking & releasing in one step,
tools usualy uses this approach.
The global memory pool (cmd->mem) should be used only for global
physical volume operations.
This patch have to be applied with all subsequent patches to complete
memory pool per vg logic.
Using separate memory pool has quite bit memory saving impact when
using large VGs, this is mainly needed when we have to use
preallocated and locked memory (and should not overflow from that
memory space).
The all_pvs list, used in vg_read, should make its own private
copy of pv structures, otherwise (when vg will use its own pool)
it will point to released memory pool.
The same applies for get_pvs() call.
Patch adds pv_list copy helper and adds explicit memory pool
parameter into _copy_pv.
(Please note that all these helper functions cannot guarantee that
vg related fields are valid - proper vg read & lock must be used
if it is requested.)
Patch fixes these problems:
- during the snapshot creation process, it needs create 2 LVs,
one is cow, second becomes snapshot.
If the code fails in vg_add_snapshot, code lvcreate will not remove
LV cow volume.
- if max_lv is set and VG contains snapshot, it can happen that
during the activation lv_count is temporarily increased over the limit
and VG metadata are not properly processed
see https://bugzilla.redhat.com/show_bug.cgi?id=490298
- vgcfgrestore alows restore with max_lv set to lower valuer that actual
LV count. This later leads to situation that max_lv is completely ignored.
- vgck doesn't call vg_validate(). It should at least try:-)
Signed-off-by: Milan Broz <mbroz@redhat.com>
This patch is not fully tested and leaves some related bugs unfixed.
Intended behaviour of the code now:
pe_start in the lvm2 format PV label header is set only by pvcreate (or
vgconvert -M2) and then preserved in *all* operations thereafter.
In some specialist cases, after the PV is added to a VG, the pe_start
field in the VG metadata may hold a different value and if so, it
overrides the other one for as long as the PV is in such a VG.
Currently, the field storing the size of the data area in the PV label
header always holds 0. As it only has meaning in the context of a
volume group, it is calculated whenever the PV is added to a VG (and can
be derived from extent_size and pe_count in the VG metadata).
