[PATCH] md: provide proper rcu_dereference / rcu_assign_pointer annotations in md

Acked-by: <paulmck@us.ibm.com>
Signed-off-by: Suzanne Wood <suzannew@cs.pdx.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/md/raid6main.c b/drivers/md/raid6main.c
index 7757869..84f3ee0 100644
--- a/drivers/md/raid6main.c
+++ b/drivers/md/raid6main.c
@@ -1464,7 +1464,7 @@
 			bi->bi_end_io = raid6_end_read_request;
 
 		rcu_read_lock();
-		rdev = conf->disks[i].rdev;
+		rdev = rcu_dereference(conf->disks[i].rdev);
 		if (rdev && rdev->faulty)
 			rdev = NULL;
 		if (rdev)
@@ -1538,7 +1538,7 @@
 
 	rcu_read_lock();
 	for (i=0; i<mddev->raid_disks; i++) {
-		mdk_rdev_t *rdev = conf->disks[i].rdev;
+		mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev);
 		if (rdev && !rdev->faulty && atomic_read(&rdev->nr_pending)) {
 			request_queue_t *r_queue = bdev_get_queue(rdev->bdev);
 
@@ -1583,7 +1583,7 @@
 
 	rcu_read_lock();
 	for (i=0; i<mddev->raid_disks && ret == 0; i++) {
-		mdk_rdev_t *rdev = conf->disks[i].rdev;
+		mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev);
 		if (rdev && !rdev->faulty) {
 			struct block_device *bdev = rdev->bdev;
 			request_queue_t *r_queue = bdev_get_queue(bdev);
@@ -2154,7 +2154,7 @@
 			found = 1;
 			if (rdev->saved_raid_disk != disk)
 				conf->fullsync = 1;
-			p->rdev = rdev;
+			rcu_assign_pointer(p->rdev, rdev);
 			break;
 		}
 	print_raid6_conf(conf);