[PATCH] md: rationalise unplug functions in md

There are currently subtle differences in the different personalities
concerning when subdevices are unplugged (faulty?  nr_pending?).  This patch
makes them sll uniform.
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/md/multipath.c

@@ -140,7 +140,7 @@ static void unplug_slaves(mddev_t *mddev)
 	spin_lock_irqsave(&conf->device_lock, flags);
 	for (i=0; i<mddev->raid_disks; i++) {
 		mdk_rdev_t *rdev = conf->multipaths[i].rdev;
-		if (rdev && !rdev->faulty) {
+		if (rdev && !rdev->faulty && atomic_read(&rdev->nr_pending)) {
 			request_queue_t *r_queue = bdev_get_queue(rdev->bdev);
 
 			atomic_inc(&rdev->nr_pending);

drivers/md/raid1.c

@@ -430,7 +430,7 @@ static void unplug_slaves(mddev_t *mddev)
 	spin_lock_irqsave(&conf->device_lock, flags);
 	for (i=0; i<mddev->raid_disks; i++) {
 		mdk_rdev_t *rdev = conf->mirrors[i].rdev;
-		if (rdev && atomic_read(&rdev->nr_pending)) {
+		if (rdev && !rdev->faulty && atomic_read(&rdev->nr_pending)) {
 			request_queue_t *r_queue = bdev_get_queue(rdev->bdev);
 
 			atomic_inc(&rdev->nr_pending);

drivers/md/raid10.c

@@ -584,7 +584,7 @@ static void unplug_slaves(mddev_t *mddev)
 	spin_lock_irqsave(&conf->device_lock, flags);
 	for (i=0; i<mddev->raid_disks; i++) {
 		mdk_rdev_t *rdev = conf->mirrors[i].rdev;
-		if (rdev && atomic_read(&rdev->nr_pending)) {
+		if (rdev && !rdev->faulty && atomic_read(&rdev->nr_pending)) {
 			request_queue_t *r_queue = bdev_get_queue(rdev->bdev);
 
 			atomic_inc(&rdev->nr_pending);

drivers/md/raid5.c

@@ -1307,13 +1307,13 @@ static void unplug_slaves(mddev_t *mddev)
 	spin_lock_irqsave(&conf->device_lock, flags);
 	for (i=0; i<mddev->raid_disks; i++) {
 		mdk_rdev_t *rdev = conf->disks[i].rdev;
-		if (rdev && atomic_read(&rdev->nr_pending)) {
+		if (rdev && !rdev->faulty && atomic_read(&rdev->nr_pending)) {
 			request_queue_t *r_queue = bdev_get_queue(rdev->bdev);
 
 			atomic_inc(&rdev->nr_pending);
 			spin_unlock_irqrestore(&conf->device_lock, flags);
 
-			if (r_queue && r_queue->unplug_fn)
+			if (r_queue->unplug_fn)
 				r_queue->unplug_fn(r_queue);
 
 			spin_lock_irqsave(&conf->device_lock, flags);

drivers/md/raid6main.c

@@ -1469,13 +1469,13 @@ static void unplug_slaves(mddev_t *mddev)
 	spin_lock_irqsave(&conf->device_lock, flags);
 	for (i=0; i<mddev->raid_disks; i++) {
 		mdk_rdev_t *rdev = conf->disks[i].rdev;
-		if (rdev && atomic_read(&rdev->nr_pending)) {
+		if (rdev && !rdev->faulty && atomic_read(&rdev->nr_pending)) {
 			request_queue_t *r_queue = bdev_get_queue(rdev->bdev);
 
 			atomic_inc(&rdev->nr_pending);
 			spin_unlock_irqrestore(&conf->device_lock, flags);
 
-			if (r_queue && r_queue->unplug_fn)
+			if (r_queue->unplug_fn)
 				r_queue->unplug_fn(r_queue);
 
 			spin_lock_irqsave(&conf->device_lock, flags);