block: remove BKL from partition ioctls

The blkpg_ioctl and blkdev_reread_part access fields of
the bdev and gendisk structures, yet they always do so
under the protection of bdev->bd_mutex, which seems
sufficient.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
cked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/block/ioctl.c b/block/ioctl.c
index 60f477c..09fd7f1 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -296,14 +296,10 @@
 			bd_release(bdev);
 		return ret;
 	case BLKPG:
-		lock_kernel();
 		ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg);
-		unlock_kernel();
 		break;
 	case BLKRRPART:
-		lock_kernel();
 		ret = blkdev_reread_part(bdev);
-		unlock_kernel();
 		break;
 	case BLKGETSIZE:
 		size = bdev->bd_inode->i_size;