diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 50c90bd03923..7b891b8f0a8d 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1504,8 +1504,8 @@ static bool f2fs_map_blocks_cached(struct inode *inode,
 		struct f2fs_dev_info *dev = &sbi->devs[bidx];
 
 		map->m_bdev = dev->bdev;
-		map->m_pblk -= dev->start_blk;
 		map->m_len = min(map->m_len, dev->end_blk + 1 - map->m_pblk);
+		map->m_pblk -= dev->start_blk;
 	} else {
 		map->m_bdev = inode->i_sb->s_bdev;
 	}