linux-toradex.git/drivers/md/raid1.c, branch v2.6.35.4

Merge commit '3ff195b011d7decf501a4d55aeed312731094796' into for-linus

2010-05-21T22:31:36+00:00

Conflicts:
	drivers/md/md.c

- Resolved conflict in md_update_sb
- Added extra 'NULL' arg to new instance of sysfs_get_dirent.

Signed-off-by: NeilBrown

md: Fix read balancing in RAID1 and RAID10 on drives > 2TB

2010-05-18T05:28:00+00:00

read_balance uses a "unsigned long" for a sector number which
will get truncated beyond 2TB.
This will cause read-balancing to be non-optimal, and can cause
data to be read from the 'wrong' branch during a resync.  This has a
very small chance of returning wrong data.

Reported-by: Jordan Russell 
Cc: stable@kernel.org
Signed-off-by: NeilBrown

md/raid1: improve printk messages

2010-05-18T05:27:59+00:00

Make sure the array name is included in a uniform way in all printk
messages.

Signed-off-by: NeilBrown

md/raid1: delay reads that could overtake behind-writes.

2010-05-18T05:27:57+00:00

When a raid1 array is configured to support write-behind
on some devices, it normally only reads from other devices.
If all devices are write-behind (because the rest have failed)
it is possible for a read request to be serviced before a
behind-write request, which would appear as data corruption.

So when forced to read from a WriteMostly device, wait for any
write-behind to complete, and don't start any more behind-writes.

Signed-off-by: NeilBrown

md/raid1: fix confusing 'redirect sector' message.

2010-05-18T05:27:56+00:00

This message seems to suggest the named device is the one on which a
read failed, however it is actually the device that the read will be
redirected to.
So make the message a little clearer.

Reported-by: Tim Burgess 
Signed-off-by: NeilBrown

md: pass mddev to make_request functions rather than request_queue

2010-05-18T05:27:55+00:00

We used to pass the personality make_request function direct
to the block layer so the first argument had to be a queue.
But now we have the intermediary md_make_request so it makes
at lot more sense to pass a struct mddev_s.
It makes it possible to have an mddev without its own queue too.

Signed-off-by: NeilBrown

md: remove ->changed and related code.

2010-05-18T05:27:53+00:00

We set ->changed to 1 and call check_disk_change at the end
of md_open so that bd_invalidated would be set and thus
partition rescan would happen appropriately.

Now that we call revalidate_disk directly, which sets bd_invalidates,
that indirection is no longer needed and can be removed.

Signed-off-by: NeilBrown

md: move io accounting out of personalities into md_make_request

2010-05-18T05:27:52+00:00

While I generally prefer letting personalities do as much as possible,
given that we have a central md_make_request anyway we may as well use
it to simplify code.
Also this centralises knowledge of ->gendisk which will help later.

Signed-off-by: NeilBrown

drivers/md: Remove unnecessary casts of void *

2010-05-18T05:27:46+00:00

void pointers do not need to be cast to other pointer types.

Signed-off-by: H Hartley Sweeten 
Signed-off-by: NeilBrown

md/raid1: fix counting of write targets.

2010-05-18T05:27:13+00:00

There is a very small race window when writing to a
RAID1 such that if a device is marked faulty at exactly the wrong
time, the write-in-progress will not be sent to the device,
but the bitmap (if present) will be updated to say that
the write was sent.

Then if the device turned out to still be usable as was re-added
to the array, the bitmap-based-resync would skip resyncing that
block, possibly leading to corruption.  This would only be a problem
if no further writes were issued to that area of the device (i.e.
that bitmap chunk).

Suitable for any pending -stable kernel.

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