LU-2642 osd-ldiskfs: Use __REQ_WRITE instead of BIO_RW.

Commit 7b6d91da removed BIO_RW and replaced it with __REQ_WRITE.
(v2.6.35)

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Change-Id: I33f87d1e7d8ffe90efcd8b173ad56d9ecf723d7a
Reviewed-on: http://review.whamcloud.com/5121
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
LU-2729 mgs: fix cleanup of nonexistant MGSSELF_NAME proc file

The mgs teardown code gets invoked in the failure case but assumes
that the MGSSELF_NAME proc file has been created. If it hasn't been
created, the proc code issues a WARN_ON.

The setup code clears the FSDB_MGS_SELF from &fsdb->fsdb_flags when it
creates the proc file, so we can key off of that to decide whether to
remove it.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Change-Id: Idf58d1fa572eeced5dbaa72f03e38ee46a708166
Reviewed-on: http://review.whamcloud.com/5122
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Niu Yawei <yawei.niu@intel.com>
Reviewed-by: James Simmons <uja.ornl@gmail.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>