linux-toradex.git/include/linux/raid/raid5.h, branch v2.6.16.2

[PATCH] md: tidy up raid5/6 hash table code

2006-01-06T16:34:06+00:00

- replace open-coded hash chain with hlist macros

- Fix hash-table size at one page - it is already quite generous, so there
  will never be a need to use multiple pages, so no need for __get_free_pages

No functional change.

Signed-off-by: Neil Brown 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] md: fix up some rdev rcu locking in raid5/6

2006-01-06T16:34:04+00:00

There is this "FIXME" comment with a typo in it!!  that been annoying me for
days, so I just had to remove it.

conf->disks[i].rdev should only be accessed if
  - we know we hold a reference or
  - the mddev->reconfig_sem is down or
  - we have a rcu_readlock

handle_stripe was referencing rdev in three places without any of these.  For
the first two, get an rcu_readlock.  For the last, the same access
(md_sync_acct call) is made a little later after the rdev has been claimed
under and rcu_readlock, if R5_Syncio is set.  So just use that access...
However R5_Syncio isn't really needed as the 'syncing' variable contains the
same information.  So use that instead.

Issues, comment, and fix are identical in raid5 and raid6.

Signed-off-by: Neil Brown 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] md: fix raid6 resync check/repair code

2006-01-06T16:34:03+00:00

raid6 currently does not check the P/Q syndromes when doing a resync, it just
calculates the correct value and writes it.  Doing the check can reduce writes
(often to 0) for a resync, and it is needed to properly implement the

  echo check > sync_action

operation.

This patch implements the appropriate checks and tidies up some related code.

It also allows raid6 user-requested resync to bypass the intent bitmap.

Signed-off-by: Neil Brown 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] md: change raid5 sysfs attribute to not create a new directory

2005-11-09T15:56:38+00:00

There isn't really a need for raid5 attributes to be an a subdirectory,
so this patch moves them from
  /sys/block/mdX/md/raid5/attribute
to
  /sys/block/mdX/md/attribute

This suggests that all md personalities should co-operate about
namespace usage, but that shouldn't be a problem.

Signed-off-by: Neil Brown 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] md: add kobject/sysfs support to raid5

2005-11-09T15:56:37+00:00

/sys/block/mdX/md/raid5/
contains raid5-related attributes.
Currently
  stripe_cache_size
is number of entries in stripe cache, and is settable.
  stripe_cache_active
is number of active entries, and in only readable.

Signed-off-by: Neil Brown 
Cc: Greg KH 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] md: better handling of readerrors with raid5.

2005-11-09T15:56:36+00:00

This patch changes the behaviour of raid5 when it gets a read error.
Instead of just failing the device, it tried to find out what should have
been there, and writes it over the bad block.  For some media-errors, this
has a reasonable chance of fixing the error.  If the write succeeds, and a
subsequent read succeeds as well, raid5 decided the address is OK and
conitnues.

Instead of failing a drive on read-error, we attempt to re-write the block,
and then re-read.  If that all works, we allow the device to remain in the
array.

Signed-off-by: Neil Brown 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] md: add write-intent-bitmap support to raid5

2005-09-09T23:39:12+00:00

Most awkward part of this is delaying write requests until bitmap updates have
been flushed.

To achieve this, we have a sequence number (seq_flush) which is incremented
each time the raid5 is unplugged.

If the raid thread notices that this has changed, it flushes bitmap changes,
and assigned the value of seq_flush to seq_write.

When a write request arrives, it is given the number from seq_write, and that
write request may not complete until seq_flush is larger than the saved seq
number.

We have a new queue for storing stripes which are waiting for a bitmap flush
and an extra flag for stripes to record if the write was 'degraded' and so
should not clear the a bit in the bitmap.

Signed-off-by: Neil Brown 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Linux-2.6.12-rc2

2005-04-16T22:20:36+00:00

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!