block: add some comments around the bio read-write flags

[linux-2.6-omap-h63xx.git] / drivers / md / multipath.c

diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index e968116e0de9699d2bef0f114ae79f638506bf1c..8bb8794129b372c9fdd065d961437c54e774d110 100644 (file)
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -147,6 +147,7 @@ static int multipath_make_request (struct request_queue *q, struct bio * bio)
        struct multipath_bh * mp_bh;
        struct multipath_info *multipath;
        const int rw = bio_data_dir(bio);
+       int cpu;
 
        if (unlikely(bio_barrier(bio))) {
                bio_endio(bio, -EOPNOTSUPP);
@@ -158,8 +159,11 @@ static int multipath_make_request (struct request_queue *q, struct bio * bio)
        mp_bh->master_bio = bio;
        mp_bh->mddev = mddev;
 
-       disk_stat_inc(mddev->gendisk, ios[rw]);
-       disk_stat_add(mddev->gendisk, sectors[rw], bio_sectors(bio));
+       cpu = part_stat_lock();
+       part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]);
+       part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw],
+                     bio_sectors(bio));
+       part_stat_unlock();
 
        mp_bh->path = multipath_map(conf);
        if (mp_bh->path < 0) {
@@ -281,13 +285,18 @@ static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
 {
        multipath_conf_t *conf = mddev->private;
        struct request_queue *q;
-       int found = 0;
+       int err = -EEXIST;
        int path;
        struct multipath_info *p;
+       int first = 0;
+       int last = mddev->raid_disks - 1;
+
+       if (rdev->raid_disk >= 0)
+               first = last = rdev->raid_disk;
 
        print_multipath_conf(conf);
 
-       for (path=0; path<mddev->raid_disks; path++) 
+       for (path = first; path <= last; path++)
                if ((p=conf->multipaths+path)->rdev == NULL) {
                        q = rdev->bdev->bd_disk->queue;
                        blk_queue_stack_limits(mddev->queue, q);
@@ -307,11 +316,13 @@ static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
                        rdev->raid_disk = path;
                        set_bit(In_sync, &rdev->flags);
                        rcu_assign_pointer(p->rdev, rdev);
-                       found = 1;
+                       err = 0;
+                       break;
                }
 
        print_multipath_conf(conf);
-       return found;
+
+       return err;
 }
 
 static int multipath_remove_disk(mddev_t *mddev, int number)
@@ -497,7 +508,7 @@ static int multipath_run (mddev_t *mddev)
        /*
         * Ok, everything is just fine now
         */
-       mddev->array_size = mddev->size;
+       mddev->array_sectors = mddev->size * 2;
 
        mddev->queue->unplug_fn = multipath_unplug;
        mddev->queue->backing_dev_info.congested_fn = multipath_congested;