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There were no messages printed upon completiion of RAID device replacement.
This could cause confusion/concern during automated recovery, because the
user sees the failure messages but no other messages indicating correction.
Read lvm.conf setting for monitoring for each command. So we should not
activate monitoring if the default compilation is set to monitor during
lvconvert commnads.
Patch also removes check for clustered VG and allows to disable monitoring
for clustered VG with the assumption, the problem with monitoring and dmeventd
flag passing for INGNORE is already fixed.
s/Issue/Use/, otherwise it is easy to misread "Issue" as "Issuing" - causing
the user confusion as to whether the action was performed automatically or
whether they need to issue the command.
'_lv_update_log_type' takes a lvconvert_params argument so that it can pass
down the user's preference of 'region_size' and allocation_policy. When
'mirror_remove_missing' was introduced (commit ID
95986e42a1) it didn't make sense to pass down
user preferences - so NULL was given instead. While it may never happen in
practice, static analysis reveals that this argument could be dereferenced.
So, if the user preferences were not passed in, glean the necessary fields
from what is already set in the LV.
Reported-by: Zdenek Kabelac <zkabelac@redhat.com>
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
(Not updating WHATSNEW for this simple clean-up.)
Move commod code to destroy orphan VG into free_orphan_vg() function.
Use orphan vgmem for creation of PV lists.
Remove some free_pv_fid() calls (FIXME: check all of them)
FIXME: Check whether we could merge release_vg back again for all VGs.
Tested condition has been already evaluated before
For strlen() code has already excluded <ID_LEN.
For repairing, already tested (!argc && !repairing) before.
Add 'blkdevname' and 'blkdevs_used' field to dmsetup info -c -o.
Add 'blkdevname' option to dmsetup ls --tree to see block device names.
Add '-o options' to dmsetup deps and ls to select device name type on output.
We want to keep this logic -
when LV is extend - extend the LV by at least given amount,
when LV is reduced - reduce the LV by at most given amount.
So for this the rounding needs to be used.
Current logic which seems to satisfy give rule is to round up all
extent values for LV resize upward except for values with '-' sign
that are round downward.
This patch also fixes the problem when lvextend --use-polices tried
to extend LV the by i.e. 20% - but the resulting 20% were smaller
the extent size thus before this patch no extension happened.
The RAID plug-in for dmeventd now calls 'lvconvert --repair' to address failures
of devices in a RAID logical volume. The action taken can be either to "warn"
or "allocate" a new device from any spares that may be available in the
volume group. The action is designated by setting 'raid_fault_policy' in
lvm.conf - the default being "warn".
RAID is not like traditional LVM mirroring. LVM mirroring required failed
devices to be removed or the logical volume would simply hang. RAID arrays can
keep on running with failed devices. In fact, for RAID types other than RAID1,
removing a device would mean substituting an error target or converting to a
lower level RAID (e.g. RAID6 -> RAID5, or RAID4/5 to RAID0). Therefore, rather
than removing a failed device unconditionally and potentially allocating a
replacement, RAID allows the user to "replace" a device with a new one. This
approach is a 1-step solution vs the current 2-step solution.
example> lvconvert --replace <dev_to_remove> vg/lv [possible_replacement_PVs]
'--replace' can be specified more than once.
example> lvconvert --replace /dev/sdb1 --replace /dev/sdc1 vg/lv
udev may also need to be disabled if you didn't build it statically too.
dmeventd.static could be fixed with some more work but I don't really see the
point: without dlopen() it's useless, and if you have dlopen(), why not support
normal shared libraries too?
Remove DM_THIN_ERROR_DEVICE_ID from API.
Remove API warning.
Drop code that was using DM_THIN_ERROR_DEVICE_ID (already commented)
Remove debug message which slipped in through some previous commit.
Since we finaly recognize thin creation only after
_determine_snapshot_type() - move _read_activation_params()
after it - so we can support lvcreate -an thin snapshot.
Always make sure table gets reloaded.
For now activate and deactivate pool volume if it's not active.
FIXME: we could do this only if we are sure some thin volume is alive.
Since activation of pool is now independent on thin activation,
user may do whatever he needs - thought preferable thin should stay alive,
but it it will be found inactivate, update_pool will bring the pool up.
All thins are created with the next activation and VG is updated
without messages. Only some basic commands works.
(i.e. lvcreate -an -V10 -T mvg/pool)
There can be some combination to confuse this system.
This functionality for snapshots is going to be interesting.
To ensure we properly handle LV cluster locking - explicitely do
not allow to change the availability of the thin pool that is in use
for some thin LV.
As soon as the thin volume is created the only way to activate pool
is via implicit dependency.
Ignore thinpool open count for lv/vgchange operations.
monitoring state of the logical volumes they are currently acting on.
Until now, every time a logical volume has been changed by a dmeventd plugin,
this plugin would have called back to dmeventd through the external FIFO
mechanism. I am fairly sure this was superfluous, inefficient and possibly even
dangerous.
The '--merge' option to lvconvert works on snapshots and RAID1. The man
pages correctly reflect this, but the CLI help output still used the term,
'SnapshotLogicalVolume'.
Workaround for the current code with big FIXME,
since proper solution for pvmove needs to be developed.
Commiting this only for the purpose to get cluster testing covered.
Example:
~> lvconvert --type raid1 vg/mirror_lv
Steps to convert "mirror" to "raid1"
1) Allocate a RAID metadata LV for each mirror image from the same PVs
on which they are located.
2) Clear the metadata LVs. This involves writing LVM metadata, so we don't
change any aspects of the mirror LV before this so that the user can easily
remove LVs from the failed convert attempt while retaining the original
mirror.
3) Remove the mirror log, if it exists.
4) Add metadata LVs to mirror LV
5) Rename mirror sub-lvs (s/mimage/rimage/)
6) Change flags and segtype from mirror to raid1
Example:
~> lvconvert --type raid1 -m 1 vg/lv
The following steps are performed to convert linear to RAID1:
1) Allocate a metadata device from the same PV as the linear device
to provide the metadata/data LV pair required for all RAID components.
2) Allocate the required number of metadata/data LV pairs for the
remaining additional images.
3) Clear the metadata LVs. This performs a LVM metadata update.
4) Create the top-level RAID LV and add the component devices.
We want to make any failure easy to unwind. This is why we don't create the
top-level LV and add the components until the last step. Should anything
happen before that, the user could simply remove the unnecessary images. Also,
we want to ensure that the metadata LVs are cleared before forming the array to
prevent stale information from polluting the new array.
A new macro 'seg_is_linear' was added to allow us to distinguish linear LVs
from striped LVs.
This patch allows a mirror to be extended without an initial resync of the
extended portion. It compliments the existing '--nosync' option to lvcreate.
This action can be done implicitly if the mirror was created with the '--nosync'
option, or explicitly if the '--nosync' option is used when extending the device.
Here are the operational criteria:
1) A mirror created with '--nosync' should extend with 'nosync' implicitly
[EXAMPLE]# lvs vg; lvextend -L +5G vg/lv ; lvs vg
LV VG Attr LSize Pool Origin Snap% Move Log Copy% Convert
lv vg Mwi-a-m- 5.00g lv_mlog 100.00
Extending 2 mirror images.
Extending logical volume lv to 10.00 GiB
Logical volume lv successfully resized
LV VG Attr LSize Pool Origin Snap% Move Log Copy% Convert
lv vg Mwi-a-m- 10.00g lv_mlog 100.00
2) The 'M' attribute ('M' signifies a mirror created with '--nosync', while 'm'
signifies a mirror created w/o '--nosync') must be preserved when extending a
mirror created with '--nosync'. See #1 for example of 'M' attribute.
3) A mirror created without '--nosync' should extend with 'nosync' only when
'--nosync' is explicitly used when extending.
[EXAMPLE]# lvs vg; lvextend -L +5G vg/lv; lvs vg
LV VG Attr LSize Pool Origin Snap% Move Log Copy% Convert
lv vg mwi-a-m- 20.00m lv_mlog 100.00
Extending 2 mirror images.
Extending logical volume lv to 5.02 GiB
Logical volume lv successfully resized
LV VG Attr LSize Pool Origin Snap% Move Log Copy% Convert
lv vg mwi-a-m- 5.02g lv_mlog 0.39
vs.
[EXAMPLE]# lvs vg; lvextend -L +5G vg/lv --nosync; lvs vg
LV VG Attr LSize Pool Origin Snap% Move Log Copy% Convert
lv vg mwi-a-m- 20.00m lv_mlog 100.00
Extending 2 mirror images.
Extending logical volume lv to 5.02 GiB
Logical volume lv successfully resized
LV VG Attr LSize Pool Origin Snap% Move Log Copy% Convert
lv vg Mwi-a-m- 5.02g lv_mlog 100.00
4) The 'm' attribute must change to 'M' when extending a mirror created without
'--nosync' is extended with the '--nosync' option. (See #3 examples above.)
5) An inactive mirror's sync percent cannot be determined definitively, so it
must not be allowed to skip resync. Instead, the extend should ask the user if
they want to extend while performing a resync.
[EXAMPLE]# lvchange -an vg/lv
[EXAMPLE]# lvextend -L +5G vg/lv
Extending 2 mirror images.
Extending logical volume lv to 10.00 GiB
vg/lv is not active. Unable to get sync percent.
Do full resync of extended portion of vg/lv? [y/n]: y
Logical volume lv successfully resized
6) A mirror that is performing recovery (as opposed to an initial sync) - like
after a failure - is not allowed to extend with either an implicit or
explicit nosync option. [You can simulate this with a 'corelog' mirror because
when it is reactivated, it must be recovered every time.]
[EXAMPLE]# lvcreate -m1 -L 5G -n lv vg --nosync --corelog
WARNING: New mirror won't be synchronised. Don't read what you didn't write!
Logical volume "lv" created
[EXAMPLE]# lvs vg
LV VG Attr LSize Pool Origin Snap% Move Log Copy% Convert
lv vg Mwi-a-m- 5.00g 100.00
[EXAMPLE]# lvchange -an vg/lv; lvchange -ay vg/lv; lvs vg
LV VG Attr LSize Pool Origin Snap% Move Log Copy% Convert
lv vg Mwi-a-m- 5.00g 0.08
[EXAMPLE]# lvextend -L +5G vg/lv
Extending 2 mirror images.
Extending logical volume lv to 10.00 GiB
vg/lv cannot be extended while it is recovering.
7) If 'no' is selected in #5 or if the condition in #6 is hit, it should not
result in the mirror being resized or the 'm/M' attribute being changed.
NOTE: A mirror created with '--nosync' behaves differently than one created
without it when performing an extension. The former cannot be extended when
the mirror is recovering (unless in-active), while the latter can. This is
a reasonable thing to do since recovery of a mirror doesn't take long (at
least in the case of an on-disk log) and it would cause far more time in
degraded mode if the extension w/o '--nosync' was allowed. It might be
reasonable to add the ability to force the operation in the future. This
should /not/ force a nosync extension, but rather force a sync'ed extension.
IOW, the user would be saying, "Yes, yes... I know recovery won't take long
and that I'll be adding significantly to the time spent in degraded mode, but
I need the extra space right now!".
The problem as reported by "ben <benscott@nwlink.com>" on lvm-devel:
vgsplit fails with mirrored mirror log
#lvs --all -o lv_name,lv_attr,devices
LV Attr Devices
MyMirror mwi--
[MyMirror_mimage_0] Iwi--- /dev/sdq(0)
[MyMirror_mimage_1] Iwi--- /dev/sdo(0)
[MyMirror_mimage_2] Iwi--- /dev/sdi(0)
[MyMirror_mlog] mwi---
[MyMirror_mlog_mimage_0] Iwi--- /dev/sds(0)
[MyMirror_mlog_mimage_1] Iwi--- /dev/sde(0)
#vgsplit -v "TestA" "TestB" "/dev/sdq" "/dev/sdo" "/dev/sdi" "/dev/sds"
"/dev/sde"
Checking for volume group "TestA"
Checking for new volume group "TestB"
Archiving volume group "TestA" metadata (seqno 213).
Can't split mirror MyMirror between two Volume Groups
AFTER FIX:
[root@bp-01 ~]# lvs -a -o name,vg_name,devices vg new
Volume group "new" not found
Skipping volume group new
LV VG Devices
lv vg lv_mimage_0(0),lv_mimage_1(0)
[lv_mimage_0] vg /dev/sdb1(0)
[lv_mimage_1] vg /dev/sdc1(0)
[lv_mlog] vg lv_mlog_mimage_0(0),lv_mlog_mimage_1(0)
[lv_mlog_mimage_0] vg /dev/sdh1(0)
[lv_mlog_mimage_1] vg /dev/sdi1(0)
[root@bp-01 ~]# vgsplit vg new /dev/sd[bchi]1
New volume group "new" successfully split from "vg"
[root@bp-01 ~]# lvs -a -o name,vg_name,devices vg new
LV VG Devices
lv new lv_mimage_0(0),lv_mimage_1(0)
[lv_mimage_0] new /dev/sdb1(0)
[lv_mimage_1] new /dev/sdc1(0)
[lv_mlog] new lv_mlog_mimage_0(0),lv_mlog_mimage_1(0)
[lv_mlog_mimage_0] new /dev/sdh1(0)
[lv_mlog_mimage_1] new /dev/sdi1(0)
If you specify the segment type (e.g. --type mirror) and the mirrors argument
as zero, it would result in a mirrored LV with only one image. While the device
may be valid in theory, it should not be allowed in practice. It also makes it
difficult on the conversion tools, since they react badly to single-image
mirrors.
LVM has huge set of options now - it's approaching 60 short-arg less options
and we get interesting case of misdetection for 'merge' option which has been
put into the middle of options with 'short_arg' - thus certainly past 65. (ASCII 'A').
To avoid confusion of short_arg with long_opt number - add '128' to all such
non-short-arg options.
Makes dumpconfig whole-section output wrong in a different way from before,
but we should be able to merge cft_cmdline properly into cmd->cft now and
remove cascade.
leaving behind the LVM-specific parts of the code (convenience wrappers that
handle `struct device` and `struct cmd_context`, basically). A number of
functions have been renamed (in addition to getting a dm_ prefix) -- namely,
all of the config interface now has a dm_config_ prefix.
~> lvconvert --splitmirrors 1 --trackchanges vg/lv
The '--trackchanges' option allows a user the ability to use an image of
a RAID1 array for the purposes of temporary read-only access. The image
can be merged back into the array at a later time and only the blocks that
have changed in the array since the split will be resync'ed. This
operation can be thought of as a partial split. The image is never completely
extracted from the array, in that the array reserves the position the device
occupied and tracks the differences between the array and the split image via
a bitmap. The image itself is rendered read-only and the name (<LV>_rimage_*)
cannot be changed. The user can complete the split (permanently splitting the
image from the array) by re-issuing the 'lvconvert' command without the
'--trackchanges' argument and specifying the '--name' argument.
~> lvconvert --splitmirrors 1 --name my_split vg/lv
Merging the tracked image back into the array is done with the '--merge'
option (included in a follow-on patch).
~> lvconvert --merge vg/lv_rimage_<n>
The internal mechanics of this are relatively simple. The 'raid' device-
mapper target allows for the specification of an empty slot in an array
via '- -'. This is what will be used if a partial activation of an array
is ever required. (It would also be possible to use 'error' targets in
place of the '- -'.) If a RAID image is found to be both read-only and
visible, then it is considered separate from the array and '- -' is used
to hold it's position in the array. So, all that needs to be done to
temporarily split an image from the array /and/ cause the kernel target's
bitmap to track (aka "mark") changes made is to make the specified image
visible and read-only. To merge the device back into the array, the image
needs to be returned to the read/write state of the top-level LV and made
invisible.
Users already have the ability to split an image from an LV of "mirror"
segtype. This patch extends that ability to LVs of "raid1" segtype.
This patch only allows a single image to be split off, however. (The
"mirror" segtype allows an arbitrary number of images to be split off.
e.g. 4-way => 3-way/linear, 2-way/2-way, linear,3-way)
Move the free_vg() to vg.c and replace free_vg with release_vg
and make the _free_vg internal.
Patch is needed for sharing VG in vginfo cache so the release_vg function name
is a better fit here.
Defer the test of the function return value after the string memory is released.
Otherwise in this error path the string would present memory leak.
(Thought in this case we are already out of memory...)
Implementation described in doc/lvm2-raid.txt.
Basic support includes:
- ability to create RAID 1/4/5/6 arrays
- ability to delete RAID arrays
- ability to display RAID arrays
Notable missing features (not included in this patch):
- ability to clean-up/repair failures
- ability to convert RAID segment types
- ability to monitor RAID segment types
The conditional is not just unnecessary, it would have been wrong. The code
is suppose to be checking if the 'splitmirrors_ARG' is negative, but it
instead is checking 'mirrors_ARG'. Rather than changing the argument being
checked, I've pulled the check entirely because 'splitmirrors_ARG' is already
guarenteed to not be negative by virtue of the fact that it is a 'int_arg'.
Negative values will be caught in _process_command_line().
We've used udev fallback code till now to check whether udev
created/removed the entries in /dev correctly and if not,
a repair was done (giving a warning messagea about that).
This patch adds a possibility to enable this additional check
and subsequent fallback only when required (debugging purposes
mostly) and trust udev completely.
So let's disable the fallback code by default and add a new
configuration option "activation/udev_fallback".
(The original code for creating the nodes will still be used
in case the device directory that is set in lvm.conf differs
from the one that udev uses and also when activation/udev_rules
is set to 0 - otherwise we would end up with no nodes/symlinks
at all)
are affected by the move. (Currently it's possible for I/O to become
trapped between suspended devices amongst other problems.
The current fix was selected so as to minimise the testing surface. I
hope eventually to replace it with a cleaner one that extends the
deptree code.
Some lvconvert scenarios still suffer from related problems.
Patch adds check for stripe not only in direct
LV segment but also in mirror image segment.
This prevents bugs like:
# lvcreate -i2 -l10 -n lv vg_test
# lvconvert -m1 -i1 vg_test/lv
# lvreduce -f -l1 vg_test/lv
WARNING: Reducing active logical volume to 4.00 MiB
THIS MAY DESTROY YOUR DATA (filesystem etc.)
Reducing logical volume lv to 4.00 MiB
Segment extent reduction 9 not divisible by #stripes 2
Logical volume lv successfully resized
# lvremove -f vg_test
Segment extent reduction 1 not divisible by #stripes 2
LV segment lv:0-4294967295 is incorrectly listed as being used by LV lv_mimage_0
Internal error: LV segments corrupted in lv_mimage_0.
We should never remove more extents than requested by user,
so round up to next stripe boundary during lvreduce.
Also this fixes round to zero sized LV bug:
# lvcreate -i2 -I 64k -l10 -n lvs vg_test
# lvreduce -f -l1 vg_test/lvs
Rounding size (1 extents) down to stripe boundary size for segment (0 extents)
WARNING: Reducing active logical volume to 0
THIS MAY DESTROY YOUR DATA (filesystem etc.)
Reducing logical volume lvs to 0
Failed to suspend lvs
Before, we used vg_write_lock_held call to determnine the way a device is
opened. Unfortunately, this opened many devices in RW mode when it was not
really necessary. With the OPTIONS+="watch" rule used in the udev rules,
this could fire numerous events while closing such devices (and it caused
useless scans from within udev rules in return).
A common bug we hit with this was with the lvremove command which was unable
to remove the LV since it was being opened from within the udev rules. This
patch should minimize such situations (at least with respect to LVM handling
of devices).
Though there's still a possibility someone will open a device 'outside' in
parallel and fire the event based on the watch rule when closing a device
once opened for RW.
allocates these buffers in such way it adds memory page for each such buffer
and size of unlock memory check will mismatch by 1 or 2 pages.
This happens when we print or read lines without '\n' so these buffers are
used. To avoid this extra allocation, use setvbuf to set these bufffers ahead.
Signed-off-by: Zdenek Kabelac <zkabelac@redhat.com>
Reviewed-by: Milan Broz <mbroz@redhat.com>
Reviewed-by: Petr Rockai <prockai@redhat.com>
Also, add a new 'obtain_device_list_from_udev' setting to lvm.conf with which
we can turn this feature on or off if needed.
If set, the cache of block device nodes with all associated symlinks
will be constructed out of the existing udev database content.
This avoids using and opening any inapplicable non-block devices or
subdirectories found in the device directory. This setting is applied
to udev-managed device directory only, other directories will be scanned
fully. LVM2 needs to be compiled with udev support for this setting to
take effect. N.B. Any device node or symlink not managed by udev in
udev directory will be ignored with this setting on.
allows us to allocate all images of a mirror (or RAID array) at one
time during create.
The current mirror implementation still requires a separate allocation
for the log, however.
As now the FID management is more complex, the code inside free_vg needs
to access some parts of memory pools which were not needed before.
For this - makes the order of unlock_and_free_vg() unconditional.
Keek using unlock_and_free_vg() API function.
For properly working VG locking mechanism only the alphabeting locking
orderer needs to be preserved.
TODO: there could be few more code parts simplified when we 'officially'
support of referencies between different memory pools.
With recent update of dm_report_field_string() API call to accept
completely const objects - we no longer need loose constness here
and keep it forwarding.
When I see 'seg_is_mirrored', I expect the argument to be an lv_segment.
In this case, it is lvcreate_params. Both structures, have a 'segtype'
entry which the macro dereferences. However, it just seems easier to
understand if we do 'segtype_is_mirrored' instead.
Since format instances will use own memory pool, it's necessary to properly
deallocate it. For now, only fid is deallocated. The PV structure itself
still uses cmd mempool mostly, but anytime we'd like to add a mempool
in the struct physical_volume, we can just rename this fn to free_pv and
add the code (like we have free_vg fn for VGs).
While STRIPE_SIZE_LIMIT * 2 is basically UINT_MAX, 32bit integer
value can already overflow durin arg size parsing.
(This really happens in test where --stripesize 4294967291 is used,
in s390x uint overflow and this test is ineffective.)
We allow writing non-orphan PVs only for resize now. The "orphan PV" assert
in pv_write fn uses the "allow_non_orphan" parameter to control this assert.
However, we should find a more elaborate solution so we can remove this
restriction altogether (pv_write together with vg_write is not atomic, we
need to find a safe mechanism so there's an easy revert possible in case of
an error).
Fixing some const warnings - with API change in:
int vg_extend(struct volume_group *vg, int pv_count, const char *const *pv_names,
Change is needed - as lvm2api expects const behaviour here.
So vg_extend() is doing local strdup for unescaping.
skip_dev_dir return const char* from const char* vg_name.
Rest of the patch is cleanup of related warnings.
Also using dm_report_filed_string() API change to simplify
casting in _string_disp and _lvname_disp.
Add configurable option to define minimal size of
of block device usable as a PV.
pv_min_size() is added to lvm-globals and it's being
initialized through _process_config.
Macro PV_MIN_SIZE is unused and removed.
New define DEFAULT_PV_MIN_SIZE_KB is added to lvm-global
and unlike PV_MIN_SIZE it uses KB units.
Should help users with various slow devices attached to the system,
which cannot be easily filtered out (like FDD on /dev/sdX):
https://bugzilla.redhat.com/show_bug.cgi?id=644578
Make configurable default behaviour how to deal with device node creates.
With udev system natural options should be 'resume'.
For older systems where user expect there is node in /dev/mapper immediately
after dmsetup create --notable - use 'create'
FIXME:
Code needs fixing passing this flag through udev cookie.
activated.
In order to achieve this, we need to be able to query whether
the origin is active exclusively (a condition of being able to
add an exclusive snapshot).
Once we are able to query the exclusive activation of an LV, we
can safely create/activate the snapshot.
A change to 'hold_lock' was also made so that a request to aquire
a WRITE lock did not replace an EX lock, which is already a form
of write lock.
Add new function dm_task_set_add_node() to select between 2 types
of node creation in device directory.
DM_ADD_NODE_ON_RESUME is now default and ensures node is created on
resume. Old original behavior is accessible with DM_ADD_NODE_ON_CREATE.
In this case node would be created during dmsetup create --notable.
For the user 2 new options for dmsetup create are added:
[{--addnodeonresume | --addnodeoncreate }]
Properly working node creation on resume is needed for proper operation
stacking and ability to correctly check in which state the device should
after whole udev transation.
As sync_local_dev_names() cannot be called within activation context,
add new parametr which allows to select if the sync call is needed
before executing new command.
a mirror image (or removing a log while adding a mirror). Advise the
user to use two separate commands instead.
This issue become especially problematic when PVs are specified, as they
tend to mean different things when adding vs removing. In a command that
mixes adding and removing, it is impossible to decern exactly what the
user wants.
This change prevents bug 603912.
