---

yaml
---
r: 360999
b: refs/heads/master
c: aec8030
h: refs/heads/master
i:
  360997: 40625db
  360995: 08925d3
  360991: 5ed3065
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9bf7a4890518186238d2579be16ecc5190a707c0
+refs/heads/master: aec8030a8745221c8658f2033b22c98528897b13

trunk/fs/btrfs/disk-io.c

@@ -62,7 +62,7 @@ static void btrfs_destroy_ordered_operations(struct btrfs_transaction *t,
 static void btrfs_destroy_ordered_extents(struct btrfs_root *root);
 static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
 				      struct btrfs_root *root);
-static void btrfs_destroy_pending_snapshots(struct btrfs_transaction *t);
+static void btrfs_evict_pending_snapshots(struct btrfs_transaction *t);
 static void btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
 static int btrfs_destroy_marked_extents(struct btrfs_root *root,
 					struct extent_io_tree *dirty_pages,
@@ -3687,7 +3687,7 @@ int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
 	return ret;
 }
 
-static void btrfs_destroy_pending_snapshots(struct btrfs_transaction *t)
+static void btrfs_evict_pending_snapshots(struct btrfs_transaction *t)
 {
 	struct btrfs_pending_snapshot *snapshot;
 	struct list_head splice;
@@ -3700,10 +3700,8 @@ static void btrfs_destroy_pending_snapshots(struct btrfs_transaction *t)
 		snapshot = list_entry(splice.next,
 				      struct btrfs_pending_snapshot,
 				      list);
-
+		snapshot->error = -ECANCELED;
 		list_del_init(&snapshot->list);
-
-		kfree(snapshot);
 	}
 }
 
@@ -3840,6 +3838,8 @@ void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
 	cur_trans->blocked = 1;
 	wake_up(&root->fs_info->transaction_blocked_wait);
 
+	btrfs_evict_pending_snapshots(cur_trans);
+
 	cur_trans->blocked = 0;
 	wake_up(&root->fs_info->transaction_wait);
 
@@ -3849,8 +3849,6 @@ void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
 	btrfs_destroy_delayed_inodes(root);
 	btrfs_assert_delayed_root_empty(root);
 
-	btrfs_destroy_pending_snapshots(cur_trans);
-
 	btrfs_destroy_marked_extents(root, &cur_trans->dirty_pages,
 				     EXTENT_DIRTY);
 	btrfs_destroy_pinned_extent(root,
@@ -3894,6 +3892,8 @@ int btrfs_cleanup_transaction(struct btrfs_root *root)
 		if (waitqueue_active(&root->fs_info->transaction_blocked_wait))
 			wake_up(&root->fs_info->transaction_blocked_wait);
 
+		btrfs_evict_pending_snapshots(t);
+
 		t->blocked = 0;
 		smp_mb();
 		if (waitqueue_active(&root->fs_info->transaction_wait))
@@ -3907,8 +3907,6 @@ int btrfs_cleanup_transaction(struct btrfs_root *root)
 		btrfs_destroy_delayed_inodes(root);
 		btrfs_assert_delayed_root_empty(root);
 
-		btrfs_destroy_pending_snapshots(t);
-
 		btrfs_destroy_delalloc_inodes(root);
 
 		spin_lock(&root->fs_info->trans_lock);

trunk/fs/btrfs/ioctl.c

@@ -596,12 +596,8 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir,
 		ret = btrfs_commit_transaction(trans,
 					       root->fs_info->extent_root);
 	}
-	if (ret) {
-		/* cleanup_transaction has freed this for us */
-		if (trans->aborted)
-			pending_snapshot = NULL;
+	if (ret)
 		goto fail;
-	}
 
 	ret = pending_snapshot->error;
 	if (ret)

trunk/fs/btrfs/transaction.c

@@ -1053,7 +1053,12 @@ int btrfs_defrag_root(struct btrfs_root *root)
 
 /*
  * new snapshots need to be created at a very specific time in the
- * transaction commit.  This does the actual creation
+ * transaction commit.  This does the actual creation.
+ *
+ * Note:
+ * If the error which may affect the commitment of the current transaction
+ * happens, we should return the error number. If the error which just affect
+ * the creation of the pending snapshots, just return 0.
  */
 static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
 				   struct btrfs_fs_info *fs_info,
@@ -1072,7 +1077,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
 	struct extent_buffer *tmp;
 	struct extent_buffer *old;
 	struct timespec cur_time = CURRENT_TIME;
-	int ret;
+	int ret = 0;
 	u64 to_reserve = 0;
 	u64 index = 0;
 	u64 objectid;
@@ -1081,40 +1086,36 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
 
 	path = btrfs_alloc_path();
 	if (!path) {
-		ret = pending->error = -ENOMEM;
-		return ret;
+		pending->error = -ENOMEM;
+		return 0;
 	}
 
 	new_root_item = kmalloc(sizeof(*new_root_item), GFP_NOFS);
 	if (!new_root_item) {
-		ret = pending->error = -ENOMEM;
+		pending->error = -ENOMEM;
 		goto root_item_alloc_fail;
 	}
 
-	ret = btrfs_find_free_objectid(tree_root, &objectid);
-	if (ret) {
-		pending->error = ret;
+	pending->error = btrfs_find_free_objectid(tree_root, &objectid);
+	if (pending->error)
 		goto no_free_objectid;
-	}
 
 	btrfs_reloc_pre_snapshot(trans, pending, &to_reserve);
 
 	if (to_reserve > 0) {
-		ret = btrfs_block_rsv_add(root, &pending->block_rsv,
-					  to_reserve,
-					  BTRFS_RESERVE_NO_FLUSH);
-		if (ret) {
-			pending->error = ret;
+		pending->error = btrfs_block_rsv_add(root,
+						     &pending->block_rsv,
+						     to_reserve,
+						     BTRFS_RESERVE_NO_FLUSH);
+		if (pending->error)
 			goto no_free_objectid;
-		}
 	}
 
-	ret = btrfs_qgroup_inherit(trans, fs_info, root->root_key.objectid,
-				   objectid, pending->inherit);
-	if (ret) {
-		pending->error = ret;
+	pending->error = btrfs_qgroup_inherit(trans, fs_info,
+					      root->root_key.objectid,
+					      objectid, pending->inherit);
+	if (pending->error)
 		goto no_free_objectid;
-	}
 
 	key.objectid = objectid;
 	key.offset = (u64)-1;
@@ -1142,7 +1143,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
 					 dentry->d_name.len, 0);
 	if (dir_item != NULL && !IS_ERR(dir_item)) {
 		pending->error = -EEXIST;
-		goto fail;
+		goto dir_item_existed;
 	} else if (IS_ERR(dir_item)) {
 		ret = PTR_ERR(dir_item);
 		btrfs_abort_transaction(trans, root, ret);
@@ -1273,6 +1274,8 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
 	if (ret)
 		btrfs_abort_transaction(trans, root, ret);
 fail:
+	pending->error = ret;
+dir_item_existed:
 	trans->block_rsv = rsv;
 	trans->bytes_reserved = 0;
 no_free_objectid:
@@ -1288,12 +1291,17 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
 static noinline int create_pending_snapshots(struct btrfs_trans_handle *trans,
 					     struct btrfs_fs_info *fs_info)
 {
-	struct btrfs_pending_snapshot *pending;
+	struct btrfs_pending_snapshot *pending, *next;
 	struct list_head *head = &trans->transaction->pending_snapshots;
+	int ret = 0;
 
-	list_for_each_entry(pending, head, list)
-		create_pending_snapshot(trans, fs_info, pending);
-	return 0;
+	list_for_each_entry_safe(pending, next, head, list) {
+		list_del(&pending->list);
+		ret = create_pending_snapshot(trans, fs_info, pending);
+		if (ret)
+			break;
+	}
+	return ret;
 }
 
 static void update_super_roots(struct btrfs_root *root)