freeze_bdev: kill bd_mount_sem

[linux-2.6-block.git] / fs / block_dev.c

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 5d1ed50bd46c591c1ef63b312c4844d013f5239b..22506eb4a58e1523ba45dc497e6bde195e0b32f5 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -216,8 +216,6 @@ EXPORT_SYMBOL(fsync_bdev);
  * freeze_bdev  --  lock a filesystem and force it into a consistent state
  * @bdev:      blockdevice to lock
  *
- * This takes the block device bd_mount_sem to make sure no new mounts
- * happen on bdev until thaw_bdev() is called.
  * If a superblock is found on this device, we take the s_umount semaphore
  * on it to make sure nobody unmounts until the snapshot creation is done.
  * The reference counter (bd_fsfreeze_count) guarantees that only the last
@@ -240,7 +238,6 @@ struct super_block *freeze_bdev(struct block_device *bdev)
        }
        bdev->bd_fsfreeze_count++;
 
-       down(&bdev->bd_mount_sem);
        sb = get_super(bdev);
        if (sb && !(sb->s_flags & MS_RDONLY)) {
                sb->s_frozen = SB_FREEZE_WRITE;
@@ -260,7 +257,6 @@ struct super_block *freeze_bdev(struct block_device *bdev)
                                        "VFS:Filesystem freeze failed\n");
                                sb->s_frozen = SB_UNFROZEN;
                                drop_super(sb);
-                               up(&bdev->bd_mount_sem);
                                bdev->bd_fsfreeze_count--;
                                mutex_unlock(&bdev->bd_fsfreeze_mutex);
                                return ERR_PTR(error);
@@ -271,7 +267,7 @@ struct super_block *freeze_bdev(struct block_device *bdev)
        sync_blockdev(bdev);
        mutex_unlock(&bdev->bd_fsfreeze_mutex);
 
-       return sb;      /* thaw_bdev releases s->s_umount and bd_mount_sem */
+       return sb;      /* thaw_bdev releases s->s_umount */
 }
 EXPORT_SYMBOL(freeze_bdev);
 
@@ -321,7 +317,6 @@ int thaw_bdev(struct block_device *bdev, struct super_block *sb)
                drop_super(sb);
        }
 
-       up(&bdev->bd_mount_sem);
        mutex_unlock(&bdev->bd_fsfreeze_mutex);
        return 0;
 }
@@ -430,7 +425,6 @@ static void init_once(void *foo)
 
        memset(bdev, 0, sizeof(*bdev));
        mutex_init(&bdev->bd_mutex);
-       sema_init(&bdev->bd_mount_sem, 1);
        INIT_LIST_HEAD(&bdev->bd_inodes);
        INIT_LIST_HEAD(&bdev->bd_list);
 #ifdef CONFIG_SYSFS