Btrfs: Add mount -o degraded to allow mounts to continue with missing devices

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 0f94a69e6eb6..454fe8103329 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -27,8 +27,10 @@ struct btrfs_device {
         struct list_head dev_alloc_list;
         struct btrfs_root *dev_root;
         struct buffer_head *pending_io;
+        u64 generation;
 
         int barriers;
+        int in_fs_metadata;
 
         spinlock_t io_lock;
 
@@ -122,6 +124,7 @@ int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
 int btrfs_scan_one_device(const char *path, int flags, void *holder,
                           struct btrfs_fs_devices **fs_devices_ret);
 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices);
+int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices);
 int btrfs_add_device(struct btrfs_trans_handle *trans,
                      struct btrfs_root *root,
                      struct btrfs_device *device);