Btrfs: Support for online FS resize (grow and shrink)

[linux-2.6-block.git] / fs / btrfs / disk-io.c

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index eebb4fb65c61cf414a96089b0ee587fc13d92cd9..de026d9d9b2b6c2013d47fafc639d5d74258e95b 100644 (file)
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -471,13 +471,17 @@ insert:
        return root;
 }
 
-struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
-                                     struct btrfs_key *location,
-                                     const char *name, int namelen)
+struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
+                                             struct btrfs_key *location)
 {
        struct btrfs_root *root;
        int ret;
 
+       if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
+               return fs_info->tree_root;
+       if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
+               return fs_info->extent_root;
+
        root = radix_tree_lookup(&fs_info->fs_roots_radix,
                                 (unsigned long)location->objectid);
        if (root)
@@ -494,6 +498,23 @@ struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
                kfree(root);
                return ERR_PTR(ret);
        }
+       ret = btrfs_find_dead_roots(fs_info->tree_root,
+                                   root->root_key.objectid, root);
+       BUG_ON(ret);
+
+       return root;
+}
+
+struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
+                                     struct btrfs_key *location,
+                                     const char *name, int namelen)
+{
+       struct btrfs_root *root;
+       int ret;
+
+       root = btrfs_read_fs_root_no_name(fs_info, location);
+       if (!root)
+               return NULL;
 
        ret = btrfs_set_root_name(root, name, namelen);
        if (ret) {
@@ -509,11 +530,6 @@ struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
                kfree(root);
                return ERR_PTR(ret);
        }
-
-       ret = btrfs_find_dead_roots(fs_info->tree_root,
-                                   root->root_key.objectid, root);
-       BUG_ON(ret);
-
        return root;
 }
 #if 0