linux.git/drivers/md, branch v3.4-rc5

md: fix possible corruption of array metadata on shutdown.

2012-04-24T00:23:16+00:00

commit c744a65c1e2d59acc54333ce8
  md: don't set md arrays to readonly on shutdown.

removed the possibility of a 'BUG' when data is written to an array
that has just been switched to read-only, but also introduced the
possibility that the array metadata could be corrupted.

If, when md_notify_reboot gets the mddev lock, the array is
in a state where it is assembled but hasn't been started (as can
happen if the personality module is not available, or in other unusual
situations), then incorrect metadata will be written out making it
impossible to re-assemble the array.

So only call __md_stop_writes() if the array has actually been
activated.

This patch is needed for any stable kernel which has had the above
commit applied.

Cc: stable@vger.kernel.org
Reported-by: Christoph Nelles 
Signed-off-by: NeilBrown

md: don't call ->add_disk unless there is good reason.

2012-04-24T00:23:14+00:00

Commit 7bfec5f35c68121e7b18

   md/raid5: If there is a spare and a want_replacement device, start replacement.

cause md_check_recovery to call ->add_disk much more often.
Instead of only when the array is degraded, it is now called whenever
md_check_recovery finds anything useful to do, which includes
updating the metadata for clean<->dirty transition.
This causes unnecessary work, and causes info messages from ->add_disk
to be reported much too often.

So refine md_check_recovery to only do any actual recovery checking
(including ->add_disk) if MD_RECOVERY_NEEDED is set.

This fix is suitable for 3.3.y:

Cc: stable@vger.kernel.org
Reported-by: Jan Ceuleers 
Signed-off-by: NeilBrown

DM RAID: Use safe version of rdev_for_each

2012-04-24T00:23:13+00:00

Fix segfault caused by using rdev_for_each instead of rdev_for_each_safe

Commit dafb20fa34320a472deb7442f25a0c086e0feb33 mistakenly replaced a safe
iterator with an unsafe one when making some macro changes.

Signed-off-by: Jonathan Brassow 
Signed-off-by: NeilBrown

md/bitmap: prevent bitmap_daemon_work running while initialising bitmap

2012-04-12T06:05:06+00:00

If a bitmap is added while the array is active, it is possible
for bitmap_daemon_work to run while the bitmap is being
initialised.
This is particularly a problem if bitmap_daemon_work sees
bitmap->filemap as non-NULL before it has been filled in properly.
So hold bitmap_info.mutex while filling in ->filemap
to prevent problems.

This patch is suitable for any -stable kernel, though it might not
apply cleanly before about 3.1.

Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown

md/raid1,raid10: Fix calculation of 'vcnt' when processing error recovery.

2012-04-12T06:04:47+00:00

If r1bio->sectors % 8 != 0,then the memcmp and a later
memcpy will omit the last bio_vec.

This is suitable for any stable kernel since 3.1 when bad-block
management was introduced.

Cc: stable@vger.kernel.org
Signed-off-by: majianpeng 
Signed-off-by: NeilBrown

MD: Bitmap version cleanup.

2012-04-12T05:55:21+00:00

bitmap_new_disk_sb() would still create V3 bitmap superblock
with host-endian layout.

Perhaps I'm confused, but shouldn't bitmap_new_disk_sb() be
creating a V4 bitmap superblock instead, that is portable,
as per comment in bitmap.h?

Signed-off-by: Andrei Warkentin 
Signed-off-by: NeilBrown

md/raid1,raid10: don't compare excess byte during consistency check.

2012-04-03T05:39:23+00:00

When comparing two pages read from different legs of a mirror, only
compare the bytes that were read, not the whole page.

In most cases we read a whole page, but in some cases with
bad blocks or odd sizes devices we might read fewer than that.

This bug has been present "forever" but at worst it might cause
a report of two many mismatches and generate a little bit
extra resync IO, so there is no need to back-port to -stable
kernels.

Reported-by: majianpeng 
Signed-off-by: NeilBrown

md/raid5: Fix a bug about judging if the operation is syncing or replacing

2012-04-03T05:37:38+00:00

When create a raid5 using assume-clean and echo check or repair to
sync_action.Then component disks did not operated IO but the raid
check/resync faster than normal.
Because the judgement in function analyse_stripe():
		if (do_recovery ||
		    sh->sector >= conf->mddev->recovery_cp)
			s->syncing = 1;
		else
			s->replacing = 1;
When check or repair,the recovery_cp == MaxSectore,so syncing equal zero
not one.

This bug was introduced by commit 9a3e1101b827
    md/raid5:  detect and handle replacements during recovery.
so this patch is suitable for 3.3-stable.

Cc: stable@vger.kernel.org
Signed-off-by: majianpeng 
Signed-off-by: NeilBrown

md/raid1:Remove unnecessary rcu_dereference(conf->mirrors[i].rdev).

2012-04-03T05:37:33+00:00

Because rde->nr_pending > 0,so can not remove this disk.
And in any case, we aren't holding rcu_read_lock()

Signed-off-by: majianpeng 
Signed-off-by: NeilBrown

md: Avoid OOPS when reshaping raid1 to raid0

2012-04-03T05:37:26+00:00

raid1 arrays do not have the notion of chunk size. Calculate the
largest chunk sector size we can use to avoid a divide by zero OOPS
when aligning the size of the new array to the chunk size.

Signed-off-by: Jes Sorensen 
Signed-off-by: NeilBrown