linux-stable.git/drivers/md/raid1.c, branch v4.13.2

md: simplify code with bio_io_error

2017-07-21T20:16:52+00:00

Since bio_io_error sets bi_status to BLK_STS_IOERR,
and calls bio_endio, so we can use it directly.

And as mentioned by Shaohua, there are also two
places in raid5.c can use bio_io_error either.

Signed-off-by: Guoqing Jiang 
Signed-off-by: Shaohua Li

md/raid1: fix writebehind bio clone

2017-07-21T19:47:20+00:00

After bio is submitted, we should not clone it as its bi_iter might be
invalid by driver. This is the case of behind_master_bio. In certain
situration, we could dispatch behind_master_bio immediately for the
first disk and then clone it for other disks.

https://bugzilla.kernel.org/show_bug.cgi?id=196383

Reported-and-tested-by: Markus 
Reviewed-by: Ming Lei 
Fix: 841c1316c7da(md: raid1: improve write behind)
Cc: stable@vger.kernel.org (4.12+)
Signed-off-by: Shaohua Li

md: raid1-10: move raid1/raid10 common code into raid1-10.c

2017-07-21T19:47:20+00:00

No function change, just move 'struct resync_pages' and related
helpers into raid1-10.c

Signed-off-by: Ming Lei 
Signed-off-by: Shaohua Li

md: raid1/raid10: initialize bvec table via bio_add_page()

2017-07-21T19:47:20+00:00

We will support multipage bvec soon, so initialize bvec
table using the standardy way instead of writing the
talbe directly. Otherwise it won't work any more once
multipage bvec is enabled.

Acked-by: Guoqing Jiang 
Signed-off-by: Ming Lei 
Signed-off-by: Shaohua Li

md: remove 'idx' from 'struct resync_pages'

2017-07-21T19:47:20+00:00

bio_add_page() won't fail for resync bio, and the page index for each
bio is same, so remove it.

More importantly the 'idx' of 'struct resync_pages' is initialized in
mempool allocator function, the current way is wrong since mempool is
only responsible for allocation, we can't use that for initialization.

Suggested-by: NeilBrown 
Reported-by: NeilBrown 
Reported-and-tested-by: Patrick 
Fixes: f0250618361d(md: raid10: don't use bio's vec table to manage resync pages)
Fixes: 98d30c5812c3(md: raid1: don't use bio's vec table to manage resync pages)
Cc: stable@vger.kernel.org (4.12+)
Signed-off-by: Ming Lei 
Signed-off-by: Shaohua Li

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

2017-07-08T19:50:18+00:00

Pull MD update from Shaohua Li:

 - fixed deadlock in MD suspend and a potential bug in bio allocation
   (Neil Brown)

 - fixed signal issue (Mikulas Patocka)

 - fixed typo in FailFast test (Guoqing Jiang)

 - other trival fixes

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  MD: fix sleep in atomic
  MD: fix a null dereference
  md: use a separate bio_set for synchronous IO.
  md: change the initialization value for a spare device spot to MD_DISK_ROLE_SPARE
  md/raid1: remove unused bio in sync_request_write
  md/raid10: fix FailFast test for wrong device
  md: don't use flush_signals in userspace processes
  md: fix deadlock between mddev_suspend() and md_write_start()

blk: replace bioset_create_nobvec() with a flags arg to bioset_create()

2017-06-18T18:40:59+00:00

"flags" arguments are often seen as good API design as they allow
easy extensibility.
bioset_create_nobvec() is implemented internally as a variation in
flags passed to __bioset_create().

To support future extension, make the internal structure part of the
API.
i.e. add a 'flags' argument to bioset_create() and discard
bioset_create_nobvec().

Note that the bio_split allocations in drivers/md/raid* do not need
the bvec mempool - they should have used bioset_create_nobvec().

Suggested-by: Christoph Hellwig 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Ming Lei 
Signed-off-by: NeilBrown 
Signed-off-by: Jens Axboe

md/raid1: remove unused bio in sync_request_write

2017-06-16T19:04:09+00:00

The "bio" is not used in sync_request_write after commit a68e58703575
("md/raid1: split out two sub-functions from sync_request_write").

Signed-off-by: Guoqing Jiang 
Signed-off-by: Shaohua Li

md: don't use flush_signals in userspace processes

2017-06-13T17:18:02+00:00

The function flush_signals clears all pending signals for the process. It
may be used by kernel threads when we need to prepare a kernel thread for
responding to signals. However using this function for an userspaces
processes is incorrect - clearing signals without the program expecting it
can cause misbehavior.

The raid1 and raid5 code uses flush_signals in its request routine because
it wants to prepare for an interruptible wait. This patch drops
flush_signals and uses sigprocmask instead to block all signals (including
SIGKILL) around the schedule() call. The signals are not lost, but the
schedule() call won't respond to them.

Signed-off-by: Mikulas Patocka 
Cc: stable@vger.kernel.org
Acked-by: NeilBrown 
Signed-off-by: Shaohua Li

md: fix deadlock between mddev_suspend() and md_write_start()

2017-06-13T17:18:01+00:00

If mddev_suspend() races with md_write_start() we can deadlock
with mddev_suspend() waiting for the request that is currently
in md_write_start() to complete the ->make_request() call,
and md_write_start() waiting for the metadata to be updated
to mark the array as 'dirty'.
As metadata updates done by md_check_recovery() only happen then
the mddev_lock() can be claimed, and as mddev_suspend() is often
called with the lock held, these threads wait indefinitely for each
other.

We fix this by having md_write_start() abort if mddev_suspend()
is happening, and ->make_request() aborts if md_write_start()
aborted.
md_make_request() can detect this abort, decrease the ->active_io
count, and wait for mddev_suspend().

Reported-by: Nix 
Fix: 68866e425be2(MD: no sync IO while suspended)
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown 
Signed-off-by: Shaohua Li