[PATCH] lockdep: use mutex_lock_nested for bd_mutex to avoid lockdep warning

Now that the nesting in blkdev_{get,put} is simpler, adding mutex_lock_nested
is trivial.

Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 19f5f15..846f32d 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -920,7 +920,7 @@ static int do_open(struct block_device *bdev, struct file *file, int for_part)
        }
        owner = disk->fops->owner;
 
-       mutex_lock(&bdev->bd_mutex);
+       mutex_lock_nested(&bdev->bd_mutex, for_part);
        if (!bdev->bd_openers) {
                bdev->bd_disk = disk;
                bdev->bd_contains = bdev;
@@ -1062,7 +1062,7 @@ static int __blkdev_put(struct block_device *bdev, int for_part)
        struct gendisk *disk = bdev->bd_disk;
        struct block_device *victim = NULL;
 
-       mutex_lock(&bdev->bd_mutex);
+       mutex_lock_nested(&bdev->bd_mutex, for_part);
        lock_kernel();
        if (for_part)
                bdev->bd_part_count--;