btrfs: don't create or leak aliased root while cleaning up orphans

[cascardo/linux.git] / fs / btrfs / root-tree.c

diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c
index f1c3086..0912960 100644 (file)
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -150,7 +150,7 @@ int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root
 
        ret = btrfs_search_slot(trans, root, key, path, 0, 1);
        if (ret < 0) {
-               btrfs_abort_transaction(trans, root, ret);
+               btrfs_abort_transaction(trans, ret);
                goto out;
        }
 
@@ -176,20 +176,20 @@ int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root
                ret = btrfs_search_slot(trans, root, key, path,
                                -1, 1);
                if (ret < 0) {
-                       btrfs_abort_transaction(trans, root, ret);
+                       btrfs_abort_transaction(trans, ret);
                        goto out;
                }
 
                ret = btrfs_del_item(trans, root, path);
                if (ret < 0) {
-                       btrfs_abort_transaction(trans, root, ret);
+                       btrfs_abort_transaction(trans, ret);
                        goto out;
                }
                btrfs_release_path(path);
                ret = btrfs_insert_empty_item(trans, root, path,
                                key, sizeof(*item));
                if (ret < 0) {
-                       btrfs_abort_transaction(trans, root, ret);
+                       btrfs_abort_transaction(trans, ret);
                        goto out;
                }
                l = path->nodes[0];
@@ -272,6 +272,23 @@ int btrfs_find_orphan_roots(struct btrfs_root *tree_root)
                root_key.objectid = key.offset;
                key.offset++;
 
+               /*
+                * The root might have been inserted already, as before we look
+                * for orphan roots, log replay might have happened, which
+                * triggers a transaction commit and qgroup accounting, which
+                * in turn reads and inserts fs roots while doing backref
+                * walking.
+                */
+               root = btrfs_lookup_fs_root(tree_root->fs_info,
+                                           root_key.objectid);
+               if (root) {
+                       WARN_ON(!test_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED,
+                                         &root->state));
+                       if (btrfs_root_refs(&root->root_item) == 0)
+                               btrfs_add_dead_root(root);
+                       continue;
+               }
+
                root = btrfs_read_fs_root(tree_root, &root_key);
                err = PTR_ERR_OR_ZERO(root);
                if (err && err != -ENOENT) {
@@ -310,16 +327,8 @@ int btrfs_find_orphan_roots(struct btrfs_root *tree_root)
                set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state);
 
                err = btrfs_insert_fs_root(root->fs_info, root);
-               /*
-                * The root might have been inserted already, as before we look
-                * for orphan roots, log replay might have happened, which
-                * triggers a transaction commit and qgroup accounting, which
-                * in turn reads and inserts fs roots while doing backref
-                * walking.
-                */
-               if (err == -EEXIST)
-                       err = 0;
                if (err) {
+                       BUG_ON(err == -EEXIST);
                        btrfs_free_fs_root(root);
                        break;
                }
@@ -448,7 +457,7 @@ again:
        ret = btrfs_insert_empty_item(trans, tree_root, path, &key,
                                      sizeof(*ref) + name_len);
        if (ret) {
-               btrfs_abort_transaction(trans, tree_root, ret);
+               btrfs_abort_transaction(trans, ret);
                btrfs_free_path(path);
                return ret;
        }