diff .prev/drivers/md/multipath.c ./drivers/md/multipath.c

--- .prev/drivers/md/multipath.c	2006-08-29 14:52:50.000000000 +1000
+++ ./drivers/md/multipath.c	2006-08-29 14:33:34.000000000 +1000

@@ -228,6 +228,28 @@ static int multipath_issue_flush(request

	rcu_read_unlock();
	return ret;
}
+static int multipath_congested(void *data, int bits)

diff .prev/drivers/md/raid1.c ./drivers/md/raid1.c

--- .prev/drivers/md/raid1.c	2006-08-29 14:52:50.000000000 +1000
+++ ./drivers/md/raid1.c	2006-08-29 14:26:59.000000000 +1000

@@ -601,6 +601,32 @@ static int raid1_issue_flush(request_que

	return ret;
}

+static int raid1_congested(void *data, int bits)
+{
+	mddev_t *mddev = data;
+	conf_t *conf = mddev_to_conf(mddev);
+	int i, ret = 0;
+
+	rcu_read_lock();
+	for (i = 0; i < mddev->raid_disks; i++) {
+		mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
+		if (rdev && !test_bit(Faulty, &rdev->flags)) {
+			request_queue_t *q = bdev_get_queue(rdev->bdev);
+
+			/* Note the '|| 1' - when read_balance prefers
+			 * non-congested targets, it can be removed
+			 */
+			if ((bits & (1<<BDI_write_congested)) || 1)
+				ret |= bdi_congested(&q->backing_dev_info, bits);
+			else
+				ret &= bdi_congested(&q->backing_dev_info, bits);
+		}
+	}
+	rcu_read_unlock();
+	return ret;
+}
+
+
/* Barriers....