[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>

1 files changed, 10 insertions, 10 deletions

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index e16f473bcf46..f12fc288f25d 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -416,10 +416,10 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio)
                 /* Choose the first operation device, for consistancy */
                 new_disk = 0;
 
-                for (rdev = conf->mirrors[new_disk].rdev;
+                for (rdev = rcu_dereference(conf->mirrors[new_disk].rdev);
                      !rdev || !rdev->in_sync
                              || test_bit(WriteMostly, &rdev->flags);
-                     rdev = conf->mirrors[++new_disk].rdev) {
+                     rdev = rcu_dereference(conf->mirrors[++new_disk].rdev)) {
 
                         if (rdev && rdev->in_sync)
                                 wonly_disk = new_disk;
@@ -434,10 +434,10 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio)
 
 
         /* make sure the disk is operational */
-        for (rdev = conf->mirrors[new_disk].rdev;
+        for (rdev = rcu_dereference(conf->mirrors[new_disk].rdev);
              !rdev || !rdev->in_sync ||
                      test_bit(WriteMostly, &rdev->flags);
-             rdev = conf->mirrors[new_disk].rdev) {
+             rdev = rcu_dereference(conf->mirrors[new_disk].rdev)) {
 
                 if (rdev && rdev->in_sync)
                         wonly_disk = new_disk;
@@ -474,7 +474,7 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio)
                         disk = conf->raid_disks;
                 disk--;
 
-                rdev = conf->mirrors[disk].rdev;
+                rdev = rcu_dereference(conf->mirrors[disk].rdev);
 
                 if (!rdev ||
                     !rdev->in_sync ||
@@ -496,7 +496,7 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio)
 
 
         if (new_disk >= 0) {
-                rdev = conf->mirrors[new_disk].rdev;
+                rdev = rcu_dereference(conf->mirrors[new_disk].rdev);
                 if (!rdev)
                         goto retry;
                 atomic_inc(&rdev->nr_pending);
@@ -522,7 +522,7 @@ static void unplug_slaves(mddev_t *mddev)
 
         rcu_read_lock();
         for (i=0; i<mddev->raid_disks; i++) {
-                mdk_rdev_t *rdev = conf->mirrors[i].rdev;
+                mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
                 if (rdev && !rdev->faulty && atomic_read(&rdev->nr_pending)) {
                         request_queue_t *r_queue = bdev_get_queue(rdev->bdev);
 
@@ -556,7 +556,7 @@ static int raid1_issue_flush(request_queue_t *q, struct gendisk *disk,
 
         rcu_read_lock();
         for (i=0; i<mddev->raid_disks && ret == 0; i++) {
-                mdk_rdev_t *rdev = conf->mirrors[i].rdev;
+                mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
                 if (rdev && !rdev->faulty) {
                         struct block_device *bdev = rdev->bdev;
                         request_queue_t *r_queue = bdev_get_queue(bdev);
@@ -728,7 +728,7 @@ static int make_request(request_queue_t *q, struct bio * bio)
 #endif
         rcu_read_lock();
         for (i = 0;  i < disks; i++) {
-                if ((rdev=conf->mirrors[i].rdev) != NULL &&
+                if ((rdev=rcu_dereference(conf->mirrors[i].rdev)) != NULL &&
                     !rdev->faulty) {
                         atomic_inc(&rdev->nr_pending);
                         if (rdev->faulty) {
@@ -954,7 +954,7 @@ static int raid1_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
                         found = 1;
                         if (rdev->saved_raid_disk != mirror)
                                 conf->fullsync = 1;
-                        p->rdev = rdev;
+                        rcu_assign_pointer(p->rdev, rdev);
                         break;
                 }