Btrfs: hold trans_mutex when using btrfs_record_root_in_trans

btrfs_record_root_in_trans needs the trans_mutex held to make sure two
callers don't race to setup the root in a given transaction.  This adds
it to all the places that were missing it.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>

3 files changed, 6 insertions, 0 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index cd86bffbdc9f..0a5d796c9f7e 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -5658,7 +5658,9 @@ static noinline int relocate_one_extent(struct btrfs_root *extent_root,
                         prev_block = block_start;
                 }
 
+                mutex_lock(&extent_root->fs_info->trans_mutex);
                 btrfs_record_root_in_trans(found_root);
+                mutex_unlock(&extent_root->fs_info->trans_mutex);
                 if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
                         /*
                          * try to update data extent references while
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 919172de5c9a..4112d53d4f4d 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -688,7 +688,9 @@ static noinline int drop_dirty_roots(struct btrfs_root *tree_root,
                 num_bytes -= btrfs_root_used(&dirty->root->root_item);
                 bytes_used = btrfs_root_used(&root->root_item);
                 if (num_bytes) {
+                        mutex_lock(&root->fs_info->trans_mutex);
                         btrfs_record_root_in_trans(root);
+                        mutex_unlock(&root->fs_info->trans_mutex);
                         btrfs_set_root_used(&root->root_item,
                                             bytes_used - num_bytes);
                 }
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 20794290256b..9c462fbd60fa 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -2832,7 +2832,9 @@ again:
                 BUG_ON(!wc.replay_dest);
 
                 wc.replay_dest->log_root = log;
+                mutex_lock(&fs_info->trans_mutex);
                 btrfs_record_root_in_trans(wc.replay_dest);
+                mutex_unlock(&fs_info->trans_mutex);
                 ret = walk_log_tree(trans, log, &wc);
                 BUG_ON(ret);