md/raid5: writes should get directed to replacement as well as original.

When writing, we need to submit two writes, one to the original, and
one to the replacement - if there is a replacement.

If the write to the replacement results in a write error, we just fail
the device.  We only try to record write errors to the original.

When writing for recovery, we shouldn't write to the original.  This
will be addressed in a subsequent patch that generally addresses
recovery.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h
index 4cfd8016010e..f6faaa16a565 100644
--- a/drivers/md/raid5.h
+++ b/drivers/md/raid5.h
@@ -259,6 +259,7 @@ struct stripe_head_state {
 enum r5dev_flags {
         R5_UPTODATE,    /* page contains current data */
         R5_LOCKED,      /* IO has been submitted on "req" */
+        R5_DOUBLE_LOCKED,/* Cannot clear R5_LOCKED until 2 writes complete */
         R5_OVERWRITE,   /* towrite covers whole page */
 /* and some that are internal to handle_stripe */
         R5_Insync,      /* rdev && rdev->in_sync at start */