linux.git/drivers/md, branch v2.6.36

md: check return code of read_sb_page

2010-10-07T01:02:50+00:00

Function read_sb_page may return ERR_PTR(...). Check for it.

Signed-off-by: Vasiliy Kulikov 
Cc: Neil Brown 
Signed-off-by: Andrew Morton 
Signed-off-by: NeilBrown

md/raid1: minor bio initialisation improvements.

2010-10-07T01:00:50+00:00

When performing a resync we pre-allocate some bios and repeatedly use
them.  This requires us to re-initialise them each time.
One field (bi_comp_cpu) and some flags weren't being initiaised
reliably.

Signed-off-by: NeilBrown

md/raid1: avoid overflow in raid1 resync when bitmap is in use.

2010-10-07T00:54:46+00:00

bitmap_start_sync returns - via a pass-by-reference variable - the
number of sectors before we need to check with the bitmap again.
Since commit ef4256733506f245 this number can be substantially larger,
2^27 is a common value.

Unfortunately it is an 'int' and so when raid1.c:sync_request shifts
it 9 places to the left it becomes 0.  This results in a zero-length
read which the scsi layer justifiably complains about.

This patch just removes the shift so the common case becomes safe with
a trivially-correct patch.

In the next merge window we will convert this 'int' to a 'sector_t'

Reported-by: "George Spelvin" 
Signed-off-by: NeilBrown

md: fix v1.x metadata update when a disk is missing.

2010-09-17T03:53:28+00:00

If an array with 1.x metadata is assembled with the last disk missing,
md doesn't properly record the fact that the disk was missing.

This is unlikely to cause a real problem as the event count will be
different to the count on the missing disk so it won't be included in
the array.  However it could still cause confusion.

So make sure we clear all the relevant slots, not just the early ones.

Signed-off-by: NeilBrown

md: call md_update_sb even for 'external' metadata arrays.

2010-09-17T03:53:13+00:00

Now that we depend on md_update_sb to clear variable bits in
mddev->flags (rather than trying not to set them) it is important to
always call md_update_sb when appropriate.

md_check_recovery has this job but explicitly avoids it for ->external
metadata arrays.  This is not longer appropraite, or needed.

However we do want to avoid taking the mddev lock if only
MD_CHANGE_PENDING is set as that is not cleared by md_update_sb for
external-metadata arrays.

Reported-by:  "Kwolek, Adam" 
Signed-off-by: NeilBrown

md: resolve confusion of MD_CHANGE_CLEAN

2010-08-30T08:06:21+00:00

MD_CHANGE_CLEAN is used for two different purposes and this leads to
confusion.
One of the purposes is largely mirrored by MD_CHANGE_PENDING which is
not used for anything else, so have MD_CHANGE_PENDING take over that
purpose fully.

The two purposes are:
 1/ tell md_update_sb that an update is needed and that it is just a
   clean/dirty transition.
 2/ tell user-space that an transition from clean to dirty is pending
    (something wants to write), and tell te kernel (by clearin the
    flag) that the transition is OK.

The first purpose remains wit MD_CHANGE_CLEAN, the second is moved
fully to MD_CHANGE_PENDING.

This means that various places which conditionally set or cleared
MD_CHANGE_CLEAN no longer need to be conditional.

Signed-off-by: NeilBrown

md: don't clear MD_CHANGE_CLEAN in md_update_sb() for external arrays

2010-08-30T08:06:20+00:00

If this bit is cleared in md_update_sb() the kernel will allow writes to the
array if userspace triggers md_allow_write(), e.g. through stripe_cache_size,
when mdmon is not active.  When mdmon is active the array transitions to
active-idle bypassing write-pending, setting up a race for mdmon to set the
array clean before a write arrives.

Signed-off-by: Dan Williams 
Signed-off-by: NeilBrown

Move .gitignore from drivers/md to lib/raid6

2010-08-30T07:35:52+00:00

Another missing bit of the raid6 -> /lib move.

Reported-by: Andreas Schwab 
Signed-off-by: NeilBrown

md raid-1/10 Fix bio_rw bit manipulations again

2010-08-18T06:16:05+00:00

commit 7b6d91daee5cac6402186ff224c3af39d79f4a0e changed the behaviour
of a few variables in raid1 and raid10 from flags to bit-sets, but
left them as type 'bool' so they did not work.

Change them (back) to unsigned long.
(historical note: see 1ef04fefe2241087d9db7e9615c3f11b516e36cf)

Signed-off-by: NeilBrown 
Reported-by: Jiri Slaby  and many others

md: provide appropriate return value for spare_active functions.

2010-08-18T02:04:32+00:00

md_check_recovery expects ->spare_active to return 'true' if any
spares were activated, but none of them do, so the consequent change
in 'degraded' is not notified through sysfs.

So count the number of spares activated, subtract it from 'degraded'
just once, and return it.

Reported-by: Adrian Drzewiecki 
Signed-off-by: NeilBrown