Btrfs: Introduce global metadata reservation

Reserve metadata space for extent tree, checksum tree and root tree

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/fs/btrfs/tree-defrag.c b/fs/btrfs/tree-defrag.c
index b10eacdb1620..f7ac8e013ed7 100644
--- a/fs/btrfs/tree-defrag.c
+++ b/fs/btrfs/tree-defrag.c
@@ -117,13 +117,14 @@ int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
                                  path->nodes[1], 0,
                                  cache_only, &last_ret,
                                  &root->defrag_progress);
-        WARN_ON(ret && ret != -EAGAIN);
+        if (ret) {
+                WARN_ON(ret == -EAGAIN);
+                goto out;
+        }
         if (next_key_ret == 0) {
                 memcpy(&root->defrag_progress, &key, sizeof(key));
                 ret = -EAGAIN;
         }
-
-        btrfs_release_path(root, path);
 out:
         if (path)
                 btrfs_free_path(path);