linux-toradex.git/drivers/md/raid10.c, branch v2.6.35.3

md/raid10: fix deadlock with unaligned read during resync

2010-08-13T20:30:49+00:00

commit 51e9ac77035a3dfcb6fc0a88a0d80b6f99b5edb1 upstream.

If the 'bio_split' path in raid10-read is used while
resync/recovery is happening it is possible to deadlock.
Fix this be elevating ->nr_waiting for the duration of both
parts of the split request.

This fixes a bug that has been present since 2.6.22
but has only started manifesting recently for unknown reasons.
It is suitable for and -stable since then.

Reported-by:  Justin Bronder 
Tested-by:  Justin Bronder 
Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

md: fix raid10 takeover: use new_layout for setup_conf

2010-06-24T03:33:51+00:00

Use mddev->new_layout in setup_conf.
Also use new_chunk, and don't set ->degraded in takeover().  That
gets set in run()

Signed-off-by: Maciej Trela 
Signed-off-by: NeilBrown

md: fix handling of array level takeover that re-arranges devices.

2010-06-24T03:33:24+00:00

Most array level changes leave the list of devices largely unchanged,
possibly causing one at the end to become redundant.
However conversions between RAID0 and RAID10 need to renumber
all devices (except 0).

This renumbering is currently being done in the ->run method when the
new personality takes over.  However this is too late as the common
code in md.c might already have invalidated some of the devices if
they had a ->raid_disk number that appeared to high.

Moving it into the ->takeover method is too early as the array is
still active at that time and wrong ->raid_disk numbers could cause
confusion.

So add a ->new_raid_disk field to mdk_rdev_s and use it to communicate
the new raid_disk number.
Now the common code knows exactly which devices need to be renumbered,
and which can be invalidated, and can do it all at a convenient time
when the array is suspend.
It can also update some symlinks in sysfs which previously were not be
updated correctly.

Reported-by: Maciej Trela 
Signed-off-by: NeilBrown

md: raid10: Fix null pointer dereference in fix_read_error()

2010-06-24T03:31:03+00:00

Such NULL pointer dereference can occur when the driver was fixing the
read errors/bad blocks and the disk was physically removed
causing a system crash. This patch check if the
rcu_dereference() returns valid rdev before accessing it in fix_read_error().

Cc: stable@kernel.org
Signed-off-by: Prasanna S. Panchamukhi 
Signed-off-by: Rob Becker 
Signed-off-by: NeilBrown

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/raid10: tidy up printk messages.

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

All raid10 printk messages now start
   md/raid10:md-device-name:

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: 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

md: Add support for Raid0->Raid10 takeover

2010-05-18T05:27:48+00:00

Signed-off-by: Maciej Trela 
Signed-off-by: NeilBrown