linux-toradex.git/drivers/md/md.c, branch v2.6.27.12

md: Fix rdev_size_store with size == 0

2008-10-22T21:21:08+00:00

commit 7d3c6f8717ee6c2bf6cba5fa0bda3b28fbda6015 upstream

Fix rdev_size_store with size == 0.
size == 0 means to use the largest size allowed by the
underlying device and is used when modifying an active array.

This fixes a regression introduced by
 commit d7027458d68b2f1752a28016dcf2ffd0a7e8f567

Signed-off-by: Chris Webb 
Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

md: Don't wait UNINTERRUPTIBLE for other resync to finish

2008-09-19T01:49:54+00:00

When two md arrays share some block device (e.g each uses different
partitions on the one device), a resync of one array will wait for
the resync on the other to finish.

This can be a long time and as it currently waits TASK_UNINTERRUPTIBLE,
the softlockup code notices and complains.

So use TASK_INTERRUPTIBLE instead and make sure to flush signals
before calling schedule.

Signed-off-by: NeilBrown

Remove invalidate_partition call from do_md_stop.

2008-09-01T02:32:52+00:00

When stopping an md array, or just switching to read-only, we
currently call invalidate_partition while holding the mddev lock.
The main reason for this is probably to ensure all dirty buffers
are flushed (invalidate_partition calls fsync_bdev).

However if any dirty buffers are found, it will almost certainly cause
a deadlock as starting writeout will require an update to the
superblock, and performing that updates requires taking the mddev
lock - which is already held.

This deadlock can be demonstrated by running "reboot -f -n" with
a root filesystem on md/raid, and some dirty buffers in memory.

All other calls to stop an array should already happen after a flush.
The normal sequence is to stop using the array (e.g. umount) which
will cause __blkdev_put to call sync_blockdev.  Then open the
array and issue the STOP_ARRAY ioctl while the buffers are all still
clean.

So this invalidate_partition is normally a no-op, except for one case
where it will cause a deadlock.

So remove it.

This patch possibly addresses the regression recored in
   http://bugzilla.kernel.org/show_bug.cgi?id=11460
and
   http://bugzilla.kernel.org/show_bug.cgi?id=11452

though it isn't yet clear how it ever worked.


Signed-off-by: NeilBrown

md: cancel check/repair requests when recovery is needed

2008-08-07T17:02:47+00:00

If a 'repair' is requested when an array is in a position to 'recover' raid1
will perform the repair while md believes a recovery is happening.  Address
this at both ends, i.e. cancel check/repair requests upon detecting a
recover condition and do not call ->spare_active after completing a
check/repair.

Signed-off-by: Dan Williams

Allow faulty devices to be removed from a readonly array.

2008-08-05T05:56:32+00:00

Removing faulty devices from an array is a two stage process.
First the device is moved from being a part of the active array
to being similar to a spare device.  Then it can be removed
by a request from user space.

The first step is currently not performed for read-only arrays,
so the second step can never succeed.

So allow readonly arrays to remove failed devices (which aren't
blocked).

Signed-off-by: NeilBrown

Fail safely when trying to grow an array with a write-intent bitmap.

2008-08-05T05:56:32+00:00

We cannot currently change the size of a write-intent bitmap.
So if we change the size of an array which has such a bitmap, it
tries to set bits beyond the end of the bitmap.

For now, simply reject any request to change the size of an array
which has a bitmap.  mdadm can remove the bitmap and add a new one
after the array has changed size.

Signed-off-by: NeilBrown

Restore force switch of md array to readonly at reboot time.

2008-08-05T05:56:31+00:00

A recent patch allowed do_md_stop to know whether it was being called
via an ioctl or not, and thus where to allow for an extra open file
descriptor when checking if it is in use.
This broke then switch to readonly performed by the shutdown notifier,
which needs to work even when the array is still (apparently) active
(as md doesn't get told when the filesystem becomes readonly).

So restore this feature by pretending that there can be lots of
file descriptors open, but we still want do_md_stop to switch to
readonly.

Signed-off-by: NeilBrown

Make writes to md/safe_mode_delay immediately effective.

2008-08-05T05:56:31+00:00

If we reduce the 'safe_mode_delay', it could still wait for the old
delay to completely expire before doing anything about safe_mode.
Thus the effect if the change is delayed.

To make the effect more immediate, run the timeout function
immediately if the delay was reduced.  This may cause it to run
slightly earlier that required, but that is the safer option.

Signed-off-by: NeilBrown

md: do not count blocked devices as spares

2008-07-29T00:52:44+00:00

remove_and_add_spares() assumes that failed devices have been hot-removed
from the array.  Removal is skipped in the 'blocked' case so do not count a
device in this state as 'spare'.

Signed-off-by: Dan Williams

md: delay notification of 'active_idle' to the recovery thread

2008-07-23T20:09:48+00:00

sysfs_notify might sleep, so do not call it from md_safemode_timeout.

Signed-off-by: Dan Williams