fix regression introduced in 8.3.3:
 commit a9b17323f2875f5d9b132c2b476a750bf44b10c7
 Author: Lars Ellenberg <lars.ellenberg@linbit.com>
 Date:   Wed Aug 12 15:18:33 2009 +0200

     out-of-spinlock completion of master bio

 : (bio_rw(bio) == READA)
    ? read_completed_with_error
    : read_ahead_completed_with_error;

is obviously not what was intended.

No one noticed because of
 * page-cache at work,
 * local RAIDs

Impact:
Failed local READs are not retried remotely,
but errored to upper layers, causing filesystems
to remount read-only, or worse.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

This is a race condition that existed for ages.
The previous commit reduces the window, this one closes it.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

This mitigates changes introduced with commit:
http://git.drbd.org/?p=drbd-8.3.git;a=commit;h=4b6803a3276652da3737

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

Depending on resync request size,
we need to account for more than one bit.

Impact: cosmetic

If SyncTarget reported correctly 100% equal checksums,
the SyncSource usually reported 12% equal checksums instead,
because it only counted requests, we typically do 32k resync requests,
and the bitmap granularity is still 4k.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

Remove unused #include <linux/version.h>('s) in
  drivers/block/drbd/drbd_main.c
  drivers/block/drbd/drbd_receiver.c
  drivers/block/drbd/drbd_worker.c

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>

Remove duplicated #include('s) in
  drivers/block/drbd/drbd_worker.c

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>

They should be reimplemented in the current scheme.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

It is force-included on the gcc command line since at least 2.6.15.
Explicit include lines seem to break compilation now in certain configurations.

Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>