diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index b9526f749049..afc3ac5e57d7 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3689,6 +3689,20 @@ static int can_overcommit(struct btrfs_root *root,
 	return 0;
 }
 
+static int writeback_inodes_sb_nr_if_idle_safe(struct super_block *sb,
+					       unsigned long nr_pages,
+					       enum wb_reason reason)
+{
+	if (!writeback_in_progress(sb->s_bdi) &&
+	    down_read_trylock(&sb->s_umount)) {
+		writeback_inodes_sb_nr(sb, nr_pages, reason);
+		up_read(&sb->s_umount);
+		return 1;
+	}
+
+	return 0;
+}
+
 /*
  * shrink metadata reservation for delalloc
  */
@@ -3721,8 +3735,9 @@ static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig,
 	while (delalloc_bytes && loops < 3) {
 		max_reclaim = min(delalloc_bytes, to_reclaim);
 		nr_pages = max_reclaim >> PAGE_CACHE_SHIFT;
-		writeback_inodes_sb_nr_if_idle(root->fs_info->sb, nr_pages,
-					       WB_REASON_FS_FREE_SPACE);
+		writeback_inodes_sb_nr_if_idle_safe(root->fs_info->sb,
+						    nr_pages,
+						    WB_REASON_FS_FREE_SPACE);
 
 		/*
 		 * We need to wait for the async pages to actually start before