Btrfs: remove transaction from btrfs send

Since daivd did the work that force us to use readonly snapshot,
we can safely remove transaction protection from btrfs send.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>

diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index 572e8c7..78a43b2 100644 (file)
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -4618,7 +4618,6 @@ out:
 static int full_send_tree(struct send_ctx *sctx)
 {
        int ret;
-       struct btrfs_trans_handle *trans = NULL;
        struct btrfs_root *send_root = sctx->send_root;
        struct btrfs_key key;
        struct btrfs_key found_key;
@@ -4640,19 +4639,6 @@ static int full_send_tree(struct send_ctx *sctx)
        key.type = BTRFS_INODE_ITEM_KEY;
        key.offset = 0;
 
-join_trans:
-       /*
-        * We need to make sure the transaction does not get committed
-        * while we do anything on commit roots. Join a transaction to prevent
-        * this.
-        */
-       trans = btrfs_join_transaction(send_root);
-       if (IS_ERR(trans)) {
-               ret = PTR_ERR(trans);
-               trans = NULL;
-               goto out;
-       }
-
        /*
         * Make sure the tree has not changed after re-joining. We detect this
         * by comparing start_ctransid and ctransid. They should always match.
@@ -4676,19 +4662,6 @@ join_trans:
                goto out_finish;
 
        while (1) {
-               /*
-                * When someone want to commit while we iterate, end the
-                * joined transaction and rejoin.
-                */
-               if (btrfs_should_end_transaction(trans, send_root)) {
-                       ret = btrfs_end_transaction(trans, send_root);
-                       trans = NULL;
-                       if (ret < 0)
-                               goto out;
-                       btrfs_release_path(path);
-                       goto join_trans;
-               }
-
                eb = path->nodes[0];
                slot = path->slots[0];
                btrfs_item_key_to_cpu(eb, &found_key, slot);
@@ -4716,12 +4689,6 @@ out_finish:
 
 out:
        btrfs_free_path(path);
-       if (trans) {
-               if (!ret)
-                       ret = btrfs_end_transaction(trans, send_root);
-               else
-                       btrfs_end_transaction(trans, send_root);
-       }
        return ret;
 }