linux-stable.git/drivers/md/raid0.c, branch v4.12.2

md/md0: optimize raid0 discard handling

2017-05-09T04:18:03+00:00

There are complaints that raid0 discard handling is slow. Currently we
divide discard request into chunks and dispatch to underlayer disks. The
block layer will do merge to form big requests. This causes a lot of
request split/merge and uses significant CPU time.

A simple idea is to calculate the range for each raid disk for an IO
request and send a discard request to raid disks, which will avoid the
split/merge completely. Previously Coly tried the approach, but the
implementation was too complex because of raid0 zones. This patch always
split bio in zone boundary and handle bio within one zone. It simplifies
the implementation a lot.

Reviewed-by: NeilBrown 
Acked-by: Coly Li 
Signed-off-by: Shaohua Li

Merge branch 'md-next' into md-linus

2017-05-01T21:09:21+00:00

md/raid0: fix up bio splitting.

2017-04-11T17:18:09+00:00

raid0_make_request() should use a private bio_set rather than the
shared fs_bio_set, which is only meant for filesystems to use.

raid0_make_request() shouldn't loop around using the bio_set
multiple times as that can deadlock.

So use mddev->bio_set and pass the tail to generic_make_request()
instead of looping on it.

Signed-off-by: NeilBrown 
Signed-off-by: Shaohua Li

md: support REQ_OP_WRITE_ZEROES

2017-04-08T17:25:38+00:00

Copy & paste from the REQ_OP_WRITE_SAME code.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Jens Axboe

md: superblock changes for PPL

2017-03-16T23:55:53+00:00

Include information about PPL location and size into mdp_superblock_1
and copy it to/from rdev. Because PPL is mutually exclusive with bitmap,
put it in place of 'bitmap_offset'. Add a new flag MD_FEATURE_PPL for
'feature_map', analogically to MD_FEATURE_BITMAP_OFFSET. Add MD_HAS_PPL
to mddev->flags to indicate that PPL is enabled on an array.

Signed-off-by: Artur Paszkiewicz 
Signed-off-by: Shaohua Li

Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md

2017-02-24T22:42:19+00:00

Pull md updates from Shaohua Li:
 "Mainly fixes bugs and improves performance:

   - Improve scalability for raid1 from Coly

   - Improve raid5-cache read performance, disk efficiency and IO
     pattern from Song and me

   - Fix a race condition of disk hotplug for linear from Coly

   - A few cleanup patches from Ming and Byungchul

   - Fix a memory leak from Neil

   - Fix WRITE SAME IO failure from me

   - Add doc for raid5-cache from me"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md: (23 commits)
  md/raid1: fix write behind issues introduced by bio_clone_bioset_partial
  md/raid1: handle flush request correctly
  md/linear: shutup lockdep warnning
  md/raid1: fix a use-after-free bug
  RAID1: avoid unnecessary spin locks in I/O barrier code
  RAID1: a new I/O barrier implementation to remove resync window
  md/raid5: Don't reinvent the wheel but use existing llist API
  md: fast clone bio in bio_clone_mddev()
  md: remove unnecessary check on mddev
  md/raid1: use bio_clone_bioset_partial() in case of write behind
  md: fail if mddev->bio_set can't be created
  block: introduce bio_clone_bioset_partial()
  md: disable WRITE SAME if it fails in underlayer disks
  md/raid5-cache: exclude reclaiming stripes in reclaim check
  md/raid5-cache: stripe reclaim only counts valid stripes
  MD: add doc for raid5-cache
  Documentation: move MD related doc into a separate dir
  md: ensure md devices are freed before module is unloaded.
  md/r5cache: improve journal device efficiency
  md/r5cache: enable chunk_aligned_read with write back cache
  ...

md: disable WRITE SAME if it fails in underlayer disks

2017-02-14T03:24:16+00:00

This makes md do the same thing as dm for write same IO failure. Please
see 7eee4ae(dm: disable WRITE SAME if it fails) for details why we need
this.

We did a little bit different than dm. Instead of disabling writesame in
the first IO error, we disable it till next writesame IO coming after
the first IO error. This way we don't need to clone a bio.

Also reported here: https://bugzilla.kernel.org/show_bug.cgi?id=118581

Suggested-by: NeilBrown 
Acked-by: NeilBrown 
Signed-off-by: Shaohua Li

block: Use pointer to backing_dev_info from request_queue

2017-02-02T15:20:48+00:00

We will want to have struct backing_dev_info allocated separately from
struct request_queue. As the first step add pointer to backing_dev_info
to request_queue and convert all users touching it. No functional
changes in this patch.

Reviewed-by: Christoph Hellwig 
Signed-off-by: Jan Kara 
Signed-off-by: Jens Axboe

md: cleanup mddev flag clear for takeover

2017-01-05T19:45:18+00:00

Commit 6995f0b (md: takeover should clear unrelated bits) clear
unrelated bits, but it's quite fragile. To avoid error in the future,
define a macro for unsupported mddev flags for each raid type and use it
to clear unsupported mddev flags. This should be less error-prone.

Suggested-by: NeilBrown 
Signed-off-by: Shaohua Li

md: takeover should clear unrelated bits

2016-12-09T06:00:11+00:00

When we change level from raid1 to raid5, the MD_FAILFAST_SUPPORTED bit
will be accidentally set, but raid5 doesn't support it. The same is true
for the MD_HAS_JOURNAL bit.

Fix: 46533ff (md: Use REQ_FAILFAST_* on metadata writes where appropriate)
Reviewed-by: NeilBrown 
Signed-off-by: Shaohua Li