btrfs: Streamline memory allocation failure handling in btrfs_add_delayed_tree_ref

Currently the function uses 2 goto labels to properly handle allocation
failures. This could be simplified by simply re-arranging the code so
that allocations are the in the beginning of the function. This allows
to use simple return statements. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index 6eb00eb..62ff545 100644 (file)
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -730,27 +730,33 @@ int btrfs_add_delayed_tree_ref(struct btrfs_trans_handle *trans,
        if (!ref)
                return -ENOMEM;
 
+       head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS);
+       if (!head_ref) {
+               kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref);
+               return -ENOMEM;
+       }
+
+       if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) &&
+           is_fstree(ref_root)) {
+               record = kmalloc(sizeof(*record), GFP_NOFS);
+               if (!record) {
+                       kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref);
+                       kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref);
+                       return -ENOMEM;
+               }
+       }
+
        if (parent)
                ref_type = BTRFS_SHARED_BLOCK_REF_KEY;
        else
                ref_type = BTRFS_TREE_BLOCK_REF_KEY;
+
        init_delayed_ref_common(fs_info, &ref->node, bytenr, num_bytes,
                                ref_root, action, ref_type);
        ref->root = ref_root;
        ref->parent = parent;
        ref->level = level;
 
-       head_ref = kmem_cache_alloc(btrfs_delayed_ref_head_cachep, GFP_NOFS);
-       if (!head_ref)
-               goto free_ref;
-
-       if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags) &&
-           is_fstree(ref_root)) {
-               record = kmalloc(sizeof(*record), GFP_NOFS);
-               if (!record)
-                       goto free_head_ref;
-       }
-
        init_delayed_ref_head(head_ref, record, bytenr, num_bytes,
                              ref_root, 0, action, false, is_system);
        head_ref->extent_op = extent_op;
@@ -779,13 +785,6 @@ int btrfs_add_delayed_tree_ref(struct btrfs_trans_handle *trans,
                btrfs_qgroup_trace_extent_post(fs_info, record);
 
        return 0;
-
-free_head_ref:
-       kmem_cache_free(btrfs_delayed_ref_head_cachep, head_ref);
-free_ref:
-       kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref);
-
-       return -ENOMEM;
 }
 
 /*