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Commit Graph

2194 Commits

Author SHA1 Message Date
Petr Rockai
c2bd285160 More of WHATS_NEW. 2011-11-21 12:44:38 +00:00
Petr Rockai
c6856ef42b Update WHATS_NEW. 2011-11-21 12:33:56 +00:00
Alasdair Kergon
bf75c30493 Don't ignore configure --mandir and --infodir. 2011-11-20 20:52:09 +00:00
Zdenek Kabelac
647c8edf82 Drop pool memory allocated in lv_has_target_type
Remove FIXMES - there should not be any pool free call since
the memory pool is from device manager, and pool is detroyed
after the operation, so doing extra free here would not help here.

However lv_has_target_type() is using cmd mempool so here the extra
call for dm_pool_free makes sence.
2011-11-18 19:42:03 +00:00
Zdenek Kabelac
900f5f8187 Replace dynamic buffer allocations for PATH_MAX
Use static buffer instead of stack allocated buffer.
This reduces stack size usage of lvm tool and the
change is very simple.

Since the whole library is not thread safe - it should not
add any new problems - and if there will be some conversion
it's easy to convert this to use some preallocated buffer.
2011-11-18 19:31:09 +00:00
Zdenek Kabelac
8deeeb07ea Unlock memory for vg_write
For write we do not need to hold memory locked.
This relaxes many conditions and avoid problems when allocating
a lot of memory for writting metadata buffers.
(In case of huge MDA size this would lead to mismatch between
locked and unlocked memory region size).

Add also internal check we are not writing in critical section.
2011-11-18 19:28:00 +00:00
Zdenek Kabelac
37f274ced9 Query before removing inactive snapshots
Removal of an inactive origin removes also all related snapshots.

When we now support 'old' external snapshots with thin volumes,
removal of pool will not only drop all thin volumes, but as
a consequence also all snapshots - which might be seen a bit
unexpected for the user - so add a query to confirm such action.

lvremove -f will skip the prompt.
2011-11-18 19:25:20 +00:00
Zdenek Kabelac
e8a40f6571 Allow to activate snapshot
Add extra code to active and deactivate related
snapshots and origin when user specifies snapshot
logical volume as lvchange parameter.

Before patch:

$> lvs -a
  LV    VG   Attr     LSize  Pool Origin Snap%  Move Log Copy%  Convert
  lvol0 mvg  owi-a-s-  1.00k
  lvol1 mvg  swi-a-s- 16.00k      lvol0    0.00
  lvol2 mvg  swi-a-s- 16.00k      lvol0    0.00

$> lvchange -an mvg/lvol2; echo $?
  Can't change snapshot logical volume "lvol2".
5

After patch:

$> lvchange -an mvg/lvol2
Change of snapshot lvol2 will also change its origin lvol0 and 1 other
snapshot(s). Proceed? [y/n]: n
  Logical volume lvol2 not changed.

$> lvchange -y -an mvg/lvol2; echo $?
0

$> lvs -a
  LV    VG   Attr     LSize  Pool Origin Snap%  Move Log Copy%  Convert
  lvol0 mvg  owi---s-  1.00k
  lvol1 mvg  swi---s- 16.00k      lvol0
  lvol2 mvg  swi---s- 16.00k      lvol0
2011-11-18 19:22:49 +00:00
Zdenek Kabelac
e858ac1546 Skip non-virtual snapshots for availability
Change the behavior of availability change.
With this patch the lvgchange returns success
when VG is properly changed.

It skips non-virtual origins from being changes when
only 'vg' is specified as lvchange -a parameter.

Before this change we had this:

$> lvs -a
  LV    VG   Attr     LSize   Pool Origin
  lvol0 mvg  owi-a-s- 128.00k
  lvol1 mvg  owi-a-s- 128.00k
  lvol2 mvg  swi-a-s-   1.25m      lvol0
  lvol3 mvg  swi-a-s-   1.25m      lvol1

$> lvchange -an mvg ; echo $?
  Can't change snapshot logical volume "lvol2".
  Can't change snapshot logical volume "lvol3".
5

$> lvs -a
  LV    VG   Attr     LSize   Pool Origin
  lvol0 mvg  owi---s- 128.00k
  lvol1 mvg  owi---s- 128.00k
  lvol2 mvg  swi---s-   1.25m      lvol0
  lvol3 mvg  swi---s-   1.25m      lvol1

$> lvchange -ay mvg ; echo $?
  Can't change snapshot logical volume "lvol2".
  Can't change snapshot logical volume "lvol3".
5

$> lvs
  LV    VG   Attr     LSize   Pool Origin
  lvol0 mvg  owi-a-s- 128.00k
  lvol1 mvg  owi-a-s- 128.00k
  lvol2 mvg  swi-a-s-   1.25m      lvol0
  lvol3 mvg  swi-a-s-   1.25m      lvol1

After commit:

$> lvs -a
  LV    VG   Attr     LSize   Pool Origin
  lvol0 mvg  owi-a-s- 128.00k
  lvol1 mvg  owi-a-s- 128.00k
  lvol2 mvg  swi-a-s-   1.25m      lvol0
  lvol3 mvg  swi-a-s-   1.25m      lvol1

$> lvchange -an mvg ; echo $?
0

$> lvs -a
  LV    VG   Attr     LSize   Pool Origin
  lvol0 mvg  owi---s- 128.00k
  lvol1 mvg  owi---s- 128.00k
  lvol2 mvg  swi---s-   1.25m      lvol0
  lvol3 mvg  swi---s-   1.25m      lvol1

$> lvchange -ay mvg ; echo $?
0

$> lvs -a
  LV    VG   Attr     LSize   Pool Origin
  lvol0 mvg  owi-a-s- 128.00k
  lvol1 mvg  owi-a-s- 128.00k
  lvol2 mvg  swi-a-s-   1.25m      lvol0
  lvol3 mvg  swi-a-s-   1.25m      lvol1
2011-11-18 19:19:22 +00:00
Zdenek Kabelac
91e4512619 Adjusted mirror region size only for mirrors and raids
Update region_size only for mirror and raid targets.
This fixes warning messages when vg is using small
extent size like 1KiB and no mirror/raid is created,
but the user still got the message:

$> vgcreate -s 1K vg  <pvs>
$> lvcreate -L10K vg
Using reduced mirror region size of 4 sectors
2011-11-15 17:32:12 +00:00
Zdenek Kabelac
8542953f74 Reorder AND test condition
Take the easiest condition for checking first since they must
apply all together, check local conditions first before doing
more expensive tests.
2011-11-15 17:27:41 +00:00
Peter Rajnoha
5680d14ecd Avoid 'mda inconsistency' by properly registering UNLABELLED_PV flag (2.02.86).
When a PV label write is deferred to a vg_write call (as introduced by a patch
in 2.02.86), the PV is flagged with the internal UNLABELLED_PV flag. However,
when calling vg_archive before vg_write, we still have the PV labelled with the
UNLABELLED_PV flag which was not recognised as a proper flag while exporting
VG metadata:

  # vgcreate vg /dev/sda
  No physical volume label read from /dev/sda
  Metadata inconsistency: Not all flags successfully exported.
  Metadata inconsistency: Not all flags successfully exported.
  Writing physical volume data to disk "/dev/sda"
  Physical volume "/dev/sda" successfully created
  Volume group "vg" successfully created
2011-11-15 11:54:15 +00:00
Alasdair Kergon
bf09a32006 Make dmsetup.static and lvm.static build when dmeventd is disabled.
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?
2011-11-14 21:30:35 +00:00
Alasdair Kergon
630b4c2111 Move gentoo MAKEDEV to /sbin in lvm2create_initrd. (James Le Cuirot) 2011-11-12 17:03:53 +00:00
Milan Broz
07113beea3 Do not scan device if it is part of active multipath.
Add filter which tries to check if scanned device is part
of active multipath.

Firstly, only SCSI major number devices are handled in filter.

Then it checks if device has exactly one holder (in sysfs) and
if it is device-mapper device and DM-UUID is prefixed by "MPATH-".

If so, this device is filtered out.

The whole filter can be switched off by setting
mpath_component_detection in lvm.conf.

https://bugzilla.redhat.com/show_bug.cgi?id=597010

Signed-off-by: Milan Broz <mbroz@redhat.com>
2011-11-11 15:11:08 +00:00
Zdenek Kabelac
65b977f249 Update lvs man page style. 2011-11-08 12:16:53 +00:00
Zdenek Kabelac
e903e37d0a Add missing default LVM_VG_NAME
Add support for exported shell variable LVM_VG_NAME also
for thins and snapshots.
2011-11-07 11:01:53 +00:00
Zdenek Kabelac
4079a8f298 Avoid lvextend to overflow
Add extra check to extent_count overflow.
Use internal define MAX_EXTENT_COUNT instead UINT32_MAX.
2011-11-04 22:49:53 +00:00
Alasdair Kergon
13dc67cda7 Add missing lvrename mirrored log recursion in for_each_sub_lv. 2011-11-04 01:31:23 +00:00
Zdenek Kabelac
2b71bcd0cb Improve lv_extend stack reporting
and some code cleanup with setting return value.
2011-10-28 20:23:24 +00:00
Zdenek Kabelac
2fa836e843 Extend virtual segment instead of adding new one
Before adding a new virtual segment to LV, check first whether
the last segment isn't already of the same type. In this case
extend last segment instead of creating the new one.

Thin volumes should have always only 1 virtual segment, but it
helps also to virtual snapshot or error segtype..
2011-10-28 20:17:55 +00:00
Zdenek Kabelac
bd4b840879 Add last_seg
Implement a function to return the last segment in a LV.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2011-10-28 20:12:54 +00:00
Zdenek Kabelac
7ad1c43b48 Add find_config_tree_str_allow_empty
Add function to allow read of empty strings as valid arguments.
Add a warning message if string argument has ignored value.
2011-10-28 20:06:49 +00:00
Jonathan Earl Brassow
682309e0b8 Disallow 'mirrored' log for cluster mirrors.
Git commit ID 0864378250 was meant to disallow
'mirrored' logs for cluster mirrors.  However, when add_mirror_log is used
to create the log (as is now the case when using 'lvcreate' or converting only
the log) the check is bypassed.

This patch adds the check to add_mirror_log.
2011-10-25 13:17:04 +00:00
Zdenek Kabelac
eafbdf3029 Don't print char type[8] as a plain string
pvck prints 'extra' character from the label since there is no '\0'
after the struct label entry and just uint64_t follows directly.
So avoid it by limiting 8 chars to be printed.

https://www.redhat.com/archives/lvm-devel/2011-January/msg00109.html

Signed-off-by: Paul Bolle <pebolle tiscali nl>
2011-10-24 10:24:39 +00:00
Zdenek Kabelac
f2c56bc3b6 Drop mempool parameter from read functions
Use implicit vgmem pool.
2011-10-23 16:05:45 +00:00
Zdenek Kabelac
72ff89d279 Always use vg memory pool for allocated lv segment
Remove mem pool parameter from alloc_lv_segment()
Since we should always allocate LV segment from the vg mempool.
2011-10-23 16:02:01 +00:00
Zdenek Kabelac
9e453cab1c Reduce stack size usage in print_log
As the buf2[] and locn[] can't be used at the same time, safe 1 page from
stack memory.
2011-10-22 16:52:00 +00:00
Zdenek Kabelac
06b8248d63 Make move_lv_segment non-static
This function could be useful for other _manip source files.

Use dm_list manipulation function for provided functionality,
which make the code more readable and avoid touching list
internal details here.
2011-10-22 16:42:10 +00:00
Alasdair Kergon
dbd60cf576 Pass exclusive LV locks to all nodes in the cluster.
This was the intended behaviour, as described in the lvchange man page, so you
have complete control through volume_list in lvm.conf, but the code seems to
have been treating -ae as local-only for a very long time.
2011-10-21 15:49:45 +00:00
Zdenek Kabelac
4d83891a67 Make units for chunksize more obvious 2011-10-21 09:53:16 +00:00
Zdenek Kabelac
789fa12d62 Improve lvcreate man page
Split syntax for thin-pool since it cannot be fully matched with snapshot.
So to avoid more confusion - take thin support into separate line.

Though still significant updates are needed for thin provisioning.
2011-10-19 16:49:13 +00:00
Petr Rockai
c266d0611a New. 2011-10-19 09:01:03 +00:00
Jonathan Earl Brassow
3b032963d5 cmirrord now returns log name to kernel in CTR so it can be registered
Version 2 of the userspace log protocol accepts return information during the
DM_ULOG_CTR exchange.  The return information contains the name of the log
device that is being used (if there is one).  The kernel can then register the
device via 'dm_get_device'.  Amoung other things, this allows for userspace to
assemble a correct dependency tree of devices - critical for LVM handling of
suspend/resume calls.

Also, update dm-log-userspace.h to match the kernel header associated with
this protocol change.  (Includes a version inc.)
2011-10-14 14:18:49 +00:00
Zdenek Kabelac
7f815706ca Fix lv_info open_count test
When verify_udev_operations was disable, code for stacking fs operation for
lvm links was completely disable - but this code was also used for collecting
information, that a new node is being created.

Add a new flag which is set when a creation of lv symlinks is requested which
should restore old behaviour of lv_info function, that has called fs_sync()
before quere for open count on device.
2011-10-14 13:23:47 +00:00
Zdenek Kabelac
8a706f836d Simplify worker loop
Do not reacquire mutex several times without a real reason.
Code readability is also better.
2011-10-11 09:54:39 +00:00
Zdenek Kabelac
96de8adcc9 Use barrier instead of mutex
Barrier is supposed to be used in situation like this
and replace tricky mutex usage, where mutex has been unlocked
by a different thread than the locking thread.
2011-10-11 09:26:04 +00:00
Zdenek Kabelac
da0ec96159 Update 2011-10-11 09:20:17 +00:00
Zdenek Kabelac
dde1ca1ef1 Update whats new 2011-10-11 09:14:51 +00:00
Zdenek Kabelac
d4f134b8f6 Check for refresh_filter failure
Properly detect if the filters were refreshed properly.

(May needs few more fixes ??)

Filter refresh may fail because it may be out of free file descriptors
when clvmd gets overloaded.
2011-10-11 09:09:00 +00:00
Zdenek Kabelac
efe62a3411 Use condition instead of sleep
Replace usleep with pthread condition to increase speed testing
(for simplicity just 1 condition for all locks).

Use thread mutex also for unlock resource (so it wakes up awaiting
threads)

Better check some error states and return error in fail case with
unlocked mutex.
2011-10-11 09:05:20 +00:00
Zdenek Kabelac
de75bc6688 Improve backtrace reporting
Add <backtrace> so the function appears logged for the fail path.
2011-10-11 08:59:42 +00:00
Zdenek Kabelac
4007ac814f Change message severity
Using log_warn to report missing symlinks as warning, since the command
itself returns as successful, we should not produce log_error().
log_warn is better fit here.
2011-10-11 08:57:13 +00:00
Jonathan Earl Brassow
f60175c308 Add the ability to convert LVs of "mirror" segtype to "raid1" segtype.
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
2011-10-07 14:56:01 +00:00
Jonathan Earl Brassow
d3582e0252 Add the ability to convert linear LVs 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.
2011-10-07 14:52:26 +00:00
Jonathan Earl Brassow
a80192b6a7 Allow 'nosync' extension of mirrors.
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!".
2011-10-06 15:32:26 +00:00
Jonathan Earl Brassow
b19f01212e Fix splitmirror in cluster having different DM/LVM views of storage.
This patch also does some clean-up of the splitmirrors code.

I've attempted to clean-up the splitmirrors code to make it easier to
understand with fewer operations.  I've tried to reduce the number of
metadata operations without compromising the intermediate stages which
are necessary for easy clean-up in the even of failure.

These changes now correctly handle cluster situations - including exclusive
cluster mirrors.  Whereas before, a splitmirror operation would result in
remote nodes having LVM commands report the newly split LV with a proper
name while DM commands would report the old (pre-split) names of the device.
IOW, there was a kernel/userspace mismatch.
2011-10-06 14:55:39 +00:00
Jonathan Earl Brassow
6c0b0e5d9a Revert initial solution to bug 733114 - I/O error message during splitmirror
The original commit comments can be located via this git commit ID:
	7d8e615c0b

There were three possible solutions to the original problem proposed in the
initial check-in.  The one chosen was as follows:
    2) Do like _remove_mirror_images does and suspend the original, then suspend
    the sub-lv (the error target), then resume the sub-lv, and finally resume the
    original LV.  This seems like extra pointless operations to me, but it doesn't
    produce the error message (although, I'm not sure why) and it allows us to
    leave the visible flag in place.
Turns out, the cluster also views the extra suspend/resume operations as
pointless too and ignores them.  So, this solution doesn't work in a cluster.
Further, I've noticed that in addition to the remote cluster nodes still getting
I/O errors from scanning the error target, they also have a different LVM and
DM views of the same LV.  IOW, while the LVM level (gotten from the LVM metadata)
sees the correct name for the newly split LV, device-mapper still maintains the
old names.

Because the original fix failed to completely fix the problem (or work-around it)
and because a better solution must be found to address the additional cluster
issue of device renaming, I am reverting the above mentioned commit.
2011-10-06 14:49:16 +00:00
Jonathan Earl Brassow
83c606ae30 This patch fixes issues with improper udev flags on sub-LVs.
The current code does not always assign proper udev flags to sub-LVs (e.g.
mirror images and log LVs).  This shows up especially during a splitmirror
operation in which an image is split off from a mirror to form a new LV.

A mirror with a disk log is actually composed of 4 different LVs: the 2
mirror images, the log, and the top-level LV that "glues" them all together.
When a 2-way mirror is split into two linear LVs, two of those LVs must be
removed.  The segments of the image which is not split off to form the new
LV are transferred to the top-level LV.  This is done so that the original
LV can maintain its major/minor, UUID, and name.  The sub-lv from which the
segments were transferred gets an error segment as a transitory process
before it is eventually removed.  (Note that if the error target was not put
in place, a resume_lv would result in two LVs pointing to the same segment!
If the machine crashes before the eventual removal of the sub-LV, the result
would be a residual LV with the same mapping as the original (now linear) LV.)
So, the two LVs that need to be removed are now the log device and the sub-LV
with the error segment.  If udev_flags are not properly set, a resume will
cause the error LV to come up and be scanned by udev.  This causes I/O errors.
Additionally, when udev scans sub-LVs (or former sub-LVs), it can cause races
when we are trying to remove those LVs.  This is especially bad during failure
conditions.

When the mirror is suspended, the top-level along with its sub-LVs are
suspended.  The changes (now 2 linear devices and the yet-to-be-removed log
and error LV) are committed.  When the resume takes place on the original
LV, there are no longer links to the other sub-lvs through the LVM metadata.
The links are implicitly handled by querying the kernel for a list of
dependencies.  This is done in the '_add_dev' function (which is recursively
called for each dependency found) - called through the following chain:
	_add_dev
	dm_tree_add_dev_with_udev_flags
	<*** DM / LVM divide ***>
	_add_dev_to_dtree
	_add_lv_to_dtree
	_create_partial_dtree
	_tree_action
	dev_manager_activate
	_lv_activate_lv
	_lv_resume
	lv_resume_if_active
When udev flags are calculated by '_get_udev_flags', it is done by referencing
the 'logical_volume' structure.  Those flags are then passed down into
'dm_tree_add_dev_with_udev_flags', which in turn passes them to '_add_dev'.
Unfortunately, when '_add_dev' is finding the dependencies, it has no way to
calculate their proper udev_flags.  This is because it is below the DM/LVM
divide - it doesn't have access to the logical_volume structure.  In fact,
'_add_dev' simply reuses the udev_flags given for the initial device!  This
virtually guarentees the udev_flags are wrong for all the dependencies unless
they are reset by some other mechanism.  The current code provides no such
mechanism.  Even if '_add_new_lv_to_dtree' were called on the sub-devices -
which it isn't - entries already in the tree are simply passed over, failing
to reset any udev_flags.  The solution must retain its implicit nature of
discovering dependencies and be able to go back over the dependencies found
to properly set the udev_flags.

My solution simply calls a new function before leaving '_add_new_lv_to_dtree'
that iterates over the dtree nodes to properly reset the udev_flags of any
children.  It is important that this function occur after the '_add_dev' has
done its job of querying the kernel for a list of dependencies.  It is this
list of children that we use to look up their respective LVs and properly
calculate the udev_flags.

This solution has worked for single machine, cluster, and cluster w/ exclusive
activation.
2011-10-06 14:45:40 +00:00
Jonathan Earl Brassow
a391248427 Fix vgsplit when there are mirrors that have mirrored logs.
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)
2011-10-06 14:17:45 +00:00