litmus-rt.git/drivers/md, branch linux-tip

md: Call blk_queue_flush() to establish flush/fua support

2010-11-24T05:40:33+00:00

Before 2.6.37, the md layer had a mechanism for catching I/Os with the
barrier flag set, and translating the barrier into barriers for all
the underlying devices.  With 2.6.37, I/O barriers have become plain
old flushes, and the md code was updated to reflect this.  However,
one piece was left out -- the md layer does not tell the block layer
that it supports flushes or FUA access at all, which results in md
silently dropping flush requests.

Since the support already seems there, just add this one piece of
bookkeeping.

Signed-off-by: Darrick J. Wong 
Signed-off-by: NeilBrown

md/raid1: really fix recovery looping when single good device fails.

2010-11-24T05:39:46+00:00

Commit 4044ba58dd15cb01797c4fd034f39ef4a75f7cc3 supposedly fixed a
problem where if a raid1 with just one good device gets a read-error
during recovery, the recovery would abort and immediately restart in
an infinite loop.

However it depended on raid1_remove_disk removing the spare device
from the array.  But that does not happen in this case.  So add a test
so that in the 'recovery_disabled' case, the device will be removed.

This suitable for any kernel since 2.6.29 which is when
recovery_disabled was introduced.

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

md: fix return value of rdev_size_change()

2010-11-24T05:36:17+00:00

When trying to grow an array by enlarging component devices,
rdev_size_store() expects the return value of rdev_size_change() to be
in sectors, but the actual value is returned in KBs.

This functionality was broken by commit
     dd8ac336c13fd8afdb082ebacb1cddd5cf727889
so this patch is suitable for any kernel since 2.6.30.

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

block: read i_size with i_size_read()

2010-11-10T13:40:53+00:00

Convert direct reads of an inode's i_size to using i_size_read().

i_size_{read,write} use a seqcount to protect reads from accessing
incomple writes.  Concurrent i_size_write()s require mutual exclussion
to protect the seqcount that is used by i_size_{read,write}.  But
i_size_read() callers do not need to use additional locking.

Signed-off-by: Mike Snitzer 
Acked-by: NeilBrown 
Acked-by: Lars Ellenberg 
Signed-off-by: Jens Axboe

md: tidy up device searches in read_balance.

2010-10-29T05:40:33+00:00

The code for searching through the device list to read-balance in
raid1 is rather clumsy and hard to follow.  Try to simplify it a bit.

No important functionality change here.


Signed-off-by: NeilBrown

md/raid1: fix some typos in comments.

2010-10-29T05:40:33+00:00

Signed-off-by: NeilBrown

md/raid1: discard unused variable.

2010-10-29T05:40:33+00:00

This structure field (flushing_bio_list) is never used, so remove it.

Signed-off-by: NeilBrown

md: unplug writes to external bitmaps.

2010-10-29T05:40:32+00:00

When writing to an 'external' bitmap we don't currently unplug the
device before waiting, so we can get a 3msec delay each time;
So use REQ_UNPLUG to force and unplug.

Signed-off-by: NeilBrown

md: use separate bio pool for each md device.

2010-10-28T06:36:15+00:00

bio_clone and bio_alloc allocate from a common bio pool.
If an md device is stacked with other devices that use this pool, or under
something like swap which uses the pool, then the multiple calls on
the pool can cause deadlocks.

So allocate a local bio pool for each md array and use that rather
than the common pool.

This pool is used both for regular IO and metadata updates.

Signed-off-by: NeilBrown

md: change type of first arg to sync_page_io.

2010-10-28T06:36:11+00:00

Currently sync_page_io takes a 'bdev'.
Every caller passes 'rdev->bdev'.
We will soon want another field out of the rdev in sync_page_io,
So just pass the rdev instead of the bdev out of it.

Signed-off-by: NeilBrown