mkfs.f2fs: avoid wrong discard of dnode

This can drop root inode, which can be caused by previous stale data.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/mkfs/f2fs_format.c b/mkfs/f2fs_format.c
index 2e9c19a..67965ed 100644 (file)
--- a/mkfs/f2fs_format.c
+++ b/mkfs/f2fs_format.c
@@ -847,6 +847,10 @@ static int f2fs_write_super_block(void)
 static int discard_obsolete_dnode(struct f2fs_node *raw_node, u_int64_t offset)
 {
        u_int64_t next_blkaddr = 0;
+       u_int64_t root_inode_pos = get_sb(main_blkaddr);
+
+       /* only root inode was written before truncating dnodes */
+       root_inode_pos += c.cur_seg[CURSEG_HOT_NODE] * c.blks_per_seg;
 
        if (c.zoned_mode)
                return 0;
@@ -869,6 +873,9 @@ static int discard_obsolete_dnode(struct f2fs_node *raw_node, u_int64_t offset)
                        return -1;
                }
                offset = next_blkaddr;
+               /* should avoid recursive chain due to stale data */
+               if (offset == root_inode_pos)
+                       break;
        } while (1);
 
        return 0;