1 files changed, 33 insertions, 30 deletions

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index bbe40e9cf923..867f06ae33d9 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -496,6 +496,7 @@ static int read_balance(conf_t *conf, r10bio_t *r10_bio)
         int disk, slot, nslot;
         const int sectors = r10_bio->sectors;
         sector_t new_distance, current_distance;
+        mdk_rdev_t *rdev;
 
         raid10_find_phys(conf, r10_bio);
         rcu_read_lock();
@@ -510,8 +511,8 @@ static int read_balance(conf_t *conf, r10bio_t *r10_bio)
                 slot = 0;
                 disk = r10_bio->devs[slot].devnum;
 
-                while (!conf->mirrors[disk].rdev ||
-                       !conf->mirrors[disk].rdev->in_sync) {
+                while ((rdev = rcu_dereference(conf->mirrors[disk].rdev)) == NULL ||
+                       !test_bit(In_sync, &rdev->flags)) {
                         slot++;
                         if (slot == conf->copies) {
                                 slot = 0;
@@ -527,8 +528,8 @@ static int read_balance(conf_t *conf, r10bio_t *r10_bio)
         /* make sure the disk is operational */
         slot = 0;
         disk = r10_bio->devs[slot].devnum;
-        while (!conf->mirrors[disk].rdev ||
-               !conf->mirrors[disk].rdev->in_sync) {
+        while ((rdev=rcu_dereference(conf->mirrors[disk].rdev)) == NULL ||
+               !test_bit(In_sync, &rdev->flags)) {
                 slot ++;
                 if (slot == conf->copies) {
                         disk = -1;
@@ -547,11 +548,11 @@ static int read_balance(conf_t *conf, r10bio_t *r10_bio)
                 int ndisk = r10_bio->devs[nslot].devnum;
 
 
-                if (!conf->mirrors[ndisk].rdev ||
-                    !conf->mirrors[ndisk].rdev->in_sync)
+                if ((rdev=rcu_dereference(conf->mirrors[ndisk].rdev)) == NULL ||
+                    !test_bit(In_sync, &rdev->flags))
                         continue;
 
-                if (!atomic_read(&conf->mirrors[ndisk].rdev->nr_pending)) {
+                if (!atomic_read(&rdev->nr_pending)) {
                         disk = ndisk;
                         slot = nslot;
                         break;
@@ -569,7 +570,7 @@ rb_out:
         r10_bio->read_slot = slot;
 /*      conf->next_seq_sect = this_sector + sectors;*/
 
-        if (disk >= 0 && conf->mirrors[disk].rdev)
+        if (disk >= 0 && (rdev=rcu_dereference(conf->mirrors[disk].rdev))!= NULL)
                 atomic_inc(&conf->mirrors[disk].rdev->nr_pending);
         rcu_read_unlock();
 
@@ -583,8 +584,8 @@ 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;
-                if (rdev && !rdev->faulty && atomic_read(&rdev->nr_pending)) {
+                mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
+                if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) {
                         request_queue_t *r_queue = bdev_get_queue(rdev->bdev);
 
                         atomic_inc(&rdev->nr_pending);
@@ -614,8 +615,8 @@ static int raid10_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;
-                if (rdev && !rdev->faulty) {
+                mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
+                if (rdev && !test_bit(Faulty, &rdev->flags)) {
                         struct block_device *bdev = rdev->bdev;
                         request_queue_t *r_queue = bdev_get_queue(bdev);
 
@@ -768,9 +769,10 @@ static int make_request(request_queue_t *q, struct bio * bio)
         rcu_read_lock();
         for (i = 0;  i < conf->copies; i++) {
                 int d = r10_bio->devs[i].devnum;
-                if (conf->mirrors[d].rdev &&
-                    !conf->mirrors[d].rdev->faulty) {
-                        atomic_inc(&conf->mirrors[d].rdev->nr_pending);
+                mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[d].rdev);
+                if (rdev &&
+                    !test_bit(Faulty, &rdev->flags)) {
+                        atomic_inc(&rdev->nr_pending);
                         r10_bio->devs[i].bio = bio;
                 } else
                         r10_bio->devs[i].bio = NULL;
@@ -824,7 +826,7 @@ static void status(struct seq_file *seq, mddev_t *mddev)
         for (i = 0; i < conf->raid_disks; i++)
                 seq_printf(seq, "%s",
                               conf->mirrors[i].rdev &&
-                              conf->mirrors[i].rdev->in_sync ? "U" : "_");
+                              test_bit(In_sync, &conf->mirrors[i].rdev->flags) ? "U" : "_");
         seq_printf(seq, "]");
 }
 
@@ -839,7 +841,7 @@ static void error(mddev_t *mddev, mdk_rdev_t *rdev)
          * next level up know.
          * else mark the drive as failed
          */
-        if (rdev->in_sync
+        if (test_bit(In_sync, &rdev->flags)
             && conf->working_disks == 1)
                 /*
                  * Don't fail the drive, just return an IO error.
@@ -849,7 +851,7 @@ static void error(mddev_t *mddev, mdk_rdev_t *rdev)
                  * really dead" tests...
                  */
                 return;
-        if (rdev->in_sync) {
+        if (test_bit(In_sync, &rdev->flags)) {
                 mddev->degraded++;
                 conf->working_disks--;
                 /*
@@ -857,8 +859,8 @@ static void error(mddev_t *mddev, mdk_rdev_t *rdev)
                  */
                 set_bit(MD_RECOVERY_ERR, &mddev->recovery);
         }
-        rdev->in_sync = 0;
-        rdev->faulty = 1;
+        clear_bit(In_sync, &rdev->flags);
+        set_bit(Faulty, &rdev->flags);
         mddev->sb_dirty = 1;
         printk(KERN_ALERT "raid10: Disk failure on %s, disabling device. \n"
                 "       Operation continuing on %d devices\n",
@@ -883,7 +885,8 @@ static void print_conf(conf_t *conf)
                 tmp = conf->mirrors + i;
                 if (tmp->rdev)
                         printk(" disk %d, wo:%d, o:%d, dev:%s\n",
-                                i, !tmp->rdev->in_sync, !tmp->rdev->faulty,
+                                i, !test_bit(In_sync, &tmp->rdev->flags),
+                                !test_bit(Faulty, &tmp->rdev->flags),
                                 bdevname(tmp->rdev->bdev,b));
         }
 }
@@ -936,11 +939,11 @@ static int raid10_spare_active(mddev_t *mddev)
         for (i = 0; i < conf->raid_disks; i++) {
                 tmp = conf->mirrors + i;
                 if (tmp->rdev
-                    && !tmp->rdev->faulty
-                    && !tmp->rdev->in_sync) {
+                    && !test_bit(Faulty, &tmp->rdev->flags)
+                    && !test_bit(In_sync, &tmp->rdev->flags)) {
                         conf->working_disks++;
                         mddev->degraded--;
-                        tmp->rdev->in_sync = 1;
+                        set_bit(In_sync, &tmp->rdev->flags);
                 }
         }
 
@@ -980,7 +983,7 @@ static int raid10_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
                         p->head_position = 0;
                         rdev->raid_disk = mirror;
                         found = 1;
-                        p->rdev = rdev;
+                        rcu_assign_pointer(p->rdev, rdev);
                         break;
                 }
 
@@ -998,7 +1001,7 @@ static int raid10_remove_disk(mddev_t *mddev, int number)
         print_conf(conf);
         rdev = p->rdev;
         if (rdev) {
-                if (rdev->in_sync ||
+                if (test_bit(In_sync, &rdev->flags) ||
                     atomic_read(&rdev->nr_pending)) {
                         err = -EBUSY;
                         goto abort;
@@ -1414,7 +1417,7 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
 
                 for (i=0 ; i<conf->raid_disks; i++)
                         if (conf->mirrors[i].rdev &&
-                            !conf->mirrors[i].rdev->in_sync) {
+                            !test_bit(In_sync, &conf->mirrors[i].rdev->flags)) {
                                 /* want to reconstruct this device */
                                 r10bio_t *rb2 = r10_bio;
 
@@ -1435,7 +1438,7 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
                                 for (j=0; j<conf->copies;j++) {
                                         int d = r10_bio->devs[j].devnum;
                                         if (conf->mirrors[d].rdev &&
-                                            conf->mirrors[d].rdev->in_sync) {
+                                            test_bit(In_sync, &conf->mirrors[d].rdev->flags)) {
                                                 /* This is where we read from */
                                                 bio = r10_bio->devs[0].bio;
                                                 bio->bi_next = biolist;
@@ -1511,7 +1514,7 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
                         bio = r10_bio->devs[i].bio;
                         bio->bi_end_io = NULL;
                         if (conf->mirrors[d].rdev == NULL ||
-                            conf->mirrors[d].rdev->faulty)
+                            test_bit(Faulty, &conf->mirrors[d].rdev->flags))
                                 continue;
                         atomic_inc(&conf->mirrors[d].rdev->nr_pending);
                         atomic_inc(&r10_bio->remaining);
@@ -1697,7 +1700,7 @@ static int run(mddev_t *mddev)
                         mddev->queue->max_sectors = (PAGE_SIZE>>9);
 
                 disk->head_position = 0;
-                if (!rdev->faulty && rdev->in_sync)
+                if (!test_bit(Faulty, &rdev->flags) && test_bit(In_sync, &rdev->flags))
                         conf->working_disks++;
         }
         conf->raid_disks = mddev->raid_disks;