1 files changed, 18 insertions, 1 deletions

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 84ecf3ab8511..58b329ddb426 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1061,7 +1061,9 @@ int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync)
         }
         mutex_unlock(&root->fs_info->trans_mutex);
 
+        root->fs_info->tree_log_batch++;
         filemap_fdatawait(inode->i_mapping);
+        root->fs_info->tree_log_batch++;
 
         /*
          * ok we haven't committed the transaction yet, lets do a commit
@@ -1076,14 +1078,29 @@ int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync)
         }
 
         ret = btrfs_log_dentry_safe(trans, root, file->f_dentry);
-        if (ret < 0)
+        if (ret < 0) {
                 goto out;
+        }
+
+        /* we've logged all the items and now have a consistent
+         * version of the file in the log.  It is possible that
+         * someone will come in and modify the file, but that's
+         * fine because the log is consistent on disk, and we
+         * have references to all of the file's extents
+         *
+         * It is possible that someone will come in and log the
+         * file again, but that will end up using the synchronization
+         * inside btrfs_sync_log to keep things safe.
+         */
+        mutex_unlock(&file->f_dentry->d_inode->i_mutex);
+
         if (ret > 0) {
                 ret = btrfs_commit_transaction(trans, root);
         } else {
                 btrfs_sync_log(trans, root);
                 ret = btrfs_end_transaction(trans, root);
         }
+        mutex_lock(&file->f_dentry->d_inode->i_mutex);
 out:
         return ret > 0 ? EIO : ret;
 }