Merge branch 'mymd/for-next' into mymd/for-linus

[cascardo/linux.git] / drivers / md / raid5.c

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 6953d78..d189e89 100644 (file)
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -3080,7 +3080,8 @@ handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
                        struct md_rdev *rdev;
                        rcu_read_lock();
                        rdev = rcu_dereference(conf->disks[i].rdev);
-                       if (rdev && test_bit(In_sync, &rdev->flags))
+                       if (rdev && test_bit(In_sync, &rdev->flags) &&
+                           !test_bit(Faulty, &rdev->flags))
                                atomic_inc(&rdev->nr_pending);
                        else
                                rdev = NULL;
@@ -3210,15 +3211,16 @@ handle_failed_sync(struct r5conf *conf, struct stripe_head *sh,
                /* During recovery devices cannot be removed, so
                 * locking and refcounting of rdevs is not needed
                 */
+               rcu_read_lock();
                for (i = 0; i < conf->raid_disks; i++) {
-                       struct md_rdev *rdev = conf->disks[i].rdev;
+                       struct md_rdev *rdev = rcu_dereference(conf->disks[i].rdev);
                        if (rdev
                            && !test_bit(Faulty, &rdev->flags)
                            && !test_bit(In_sync, &rdev->flags)
                            && !rdev_set_badblocks(rdev, sh->sector,
                                                   STRIPE_SECTORS, 0))
                                abort = 1;
-                       rdev = conf->disks[i].replacement;
+                       rdev = rcu_dereference(conf->disks[i].replacement);
                        if (rdev
                            && !test_bit(Faulty, &rdev->flags)
                            && !test_bit(In_sync, &rdev->flags)
@@ -3226,6 +3228,7 @@ handle_failed_sync(struct r5conf *conf, struct stripe_head *sh,
                                                   STRIPE_SECTORS, 0))
                                abort = 1;
                }
+               rcu_read_unlock();
                if (abort)
                        conf->recovery_disabled =
                                conf->mddev->recovery_disabled;
@@ -3237,15 +3240,16 @@ static int want_replace(struct stripe_head *sh, int disk_idx)
 {
        struct md_rdev *rdev;
        int rv = 0;
-       /* Doing recovery so rcu locking not required */
-       rdev = sh->raid_conf->disks[disk_idx].replacement;
+
+       rcu_read_lock();
+       rdev = rcu_dereference(sh->raid_conf->disks[disk_idx].replacement);
        if (rdev
            && !test_bit(Faulty, &rdev->flags)
            && !test_bit(In_sync, &rdev->flags)
            && (rdev->recovery_offset <= sh->sector
                || rdev->mddev->recovery_cp <= sh->sector))
                rv = 1;
-
+       rcu_read_unlock();
        return rv;
 }
 
@@ -3600,7 +3604,7 @@ static void handle_stripe_dirtying(struct r5conf *conf,
        pr_debug("for sector %llu, rmw=%d rcw=%d\n",
                (unsigned long long)sh->sector, rmw, rcw);
        set_bit(STRIPE_HANDLE, &sh->state);
-       if ((rmw < rcw || (rmw == rcw && conf->rmw_level == PARITY_ENABLE_RMW)) && rmw > 0) {
+       if ((rmw < rcw || (rmw == rcw && conf->rmw_level == PARITY_PREFER_RMW)) && rmw > 0) {
                /* prefer read-modify-write, but need to get some data */
                if (conf->mddev->queue)
                        blk_add_trace_msg(conf->mddev->queue,
@@ -3627,7 +3631,7 @@ static void handle_stripe_dirtying(struct r5conf *conf,
                        }
                }
        }
-       if ((rcw < rmw || (rcw == rmw && conf->rmw_level != PARITY_ENABLE_RMW)) && rcw > 0) {
+       if ((rcw < rmw || (rcw == rmw && conf->rmw_level != PARITY_PREFER_RMW)) && rcw > 0) {
                /* want reconstruct write, but need to get some data */
                int qread =0;
                rcw = 0;
@@ -7066,10 +7070,12 @@ static void raid5_status(struct seq_file *seq, struct mddev *mddev)
        seq_printf(seq, " level %d, %dk chunk, algorithm %d", mddev->level,
                conf->chunk_sectors / 2, mddev->layout);
        seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->raid_disks - mddev->degraded);
-       for (i = 0; i < conf->raid_disks; i++)
-               seq_printf (seq, "%s",
-                              conf->disks[i].rdev &&
-                              test_bit(In_sync, &conf->disks[i].rdev->flags) ? "U" : "_");
+       rcu_read_lock();
+       for (i = 0; i < conf->raid_disks; i++) {
+               struct md_rdev *rdev = rcu_dereference(conf->disks[i].rdev);
+               seq_printf (seq, "%s", rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_");
+       }
+       rcu_read_unlock();
        seq_printf (seq, "]");
 }
 
@@ -7191,12 +7197,15 @@ static int raid5_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
                goto abort;
        }
        *rdevp = NULL;
-       synchronize_rcu();
-       if (atomic_read(&rdev->nr_pending)) {
-               /* lost the race, try later */
-               err = -EBUSY;
-               *rdevp = rdev;
-       } else if (p->replacement) {
+       if (!test_bit(RemoveSynchronized, &rdev->flags)) {
+               synchronize_rcu();
+               if (atomic_read(&rdev->nr_pending)) {
+                       /* lost the race, try later */
+                       err = -EBUSY;
+                       *rdevp = rdev;
+               }
+       }
+       if (p->replacement) {
                /* We must have just cleared 'rdev' */
                p->rdev = p->replacement;
                clear_bit(Replacement, &p->replacement->flags);