diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 6500f9e23330..b4048c1b3d9b 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -859,7 +859,7 @@ static void btrfs_close_bdev(struct btrfs_device *device) blkdev_put(device->bdev, device->mode); } -static void btrfs_close_one_device(struct btrfs_device *device) +static void btrfs_prepare_close_one_device(struct btrfs_device *device) { struct btrfs_fs_devices *fs_devices = device->fs_devices; struct btrfs_device *new_device; @@ -877,8 +877,6 @@ static void btrfs_close_one_device(struct btrfs_device *device) if (device->missing) fs_devices->missing_devices--; - btrfs_close_bdev(device); - new_device = btrfs_alloc_device(NULL, &device->devid, device->uuid); BUG_ON(IS_ERR(new_device)); /* -ENOMEM */ @@ -892,23 +890,39 @@ static void btrfs_close_one_device(struct btrfs_device *device) list_replace_rcu(&device->dev_list, &new_device->dev_list); new_device->fs_devices = device->fs_devices; - - call_rcu(&device->rcu, free_device); } static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) { struct btrfs_device *device, *tmp; + struct list_head pending_put; + + INIT_LIST_HEAD(&pending_put); if (--fs_devices->opened > 0) return 0; mutex_lock(&fs_devices->device_list_mutex); list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list) { - btrfs_close_one_device(device); + btrfs_prepare_close_one_device(device); + list_add(&device->dev_list, &pending_put); } mutex_unlock(&fs_devices->device_list_mutex); + /* + * btrfs_show_devname() is using the device_list_mutex, + * sometimes call to blkdev_put() leads vfs calling + * into this func. So do put outside of device_list_mutex, + * as of now. + */ + while (!list_empty(&pending_put)) { + device = list_first_entry(&pending_put, + struct btrfs_device, dev_list); + list_del(&device->dev_list); + btrfs_close_bdev(device); + call_rcu(&device->rcu, free_device); + } + WARN_ON(fs_devices->open_devices); WARN_ON(fs_devices->rw_devices); fs_devices->opened = 0;