diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 8aef1abc910a..8780f3d737c4 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -2322,6 +2322,7 @@ static int prepare_write_begin(struct f2fs_sb_info *sbi,
 	bool locked = false;
 	struct extent_info ei = {0,0,0};
 	int err = 0;
+	int flag;
 
 	/*
 	 * we already allocated all the blocks, so we don't need to get
@@ -2331,9 +2332,15 @@ static int prepare_write_begin(struct f2fs_sb_info *sbi,
 			!is_inode_flag_set(inode, FI_NO_PREALLOC))
 		return 0;
 
+	/* f2fs_lock_op avoids race between write CP and convert_inline_page */
+	if (f2fs_has_inline_data(inode) && pos + len > MAX_INLINE_DATA(inode))
+		flag = F2FS_GET_BLOCK_DEFAULT;
+	else
+		flag = F2FS_GET_BLOCK_PRE_AIO;
+
 	if (f2fs_has_inline_data(inode) ||
 			(pos & PAGE_MASK) >= i_size_read(inode)) {
-		__do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, true);
+		__do_map_lock(sbi, flag, true);
 		locked = true;
 	}
 restart:
@@ -2371,6 +2378,7 @@ static int prepare_write_begin(struct f2fs_sb_info *sbi,
 				f2fs_put_dnode(&dn);
 				__do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO,
 								true);
+				WARN_ON(flag != F2FS_GET_BLOCK_PRE_AIO);
 				locked = true;
 				goto restart;
 			}
@@ -2384,7 +2392,7 @@ static int prepare_write_begin(struct f2fs_sb_info *sbi,
 	f2fs_put_dnode(&dn);
 unlock_out:
 	if (locked)
-		__do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, false);
+		__do_map_lock(sbi, flag, false);
 	return err;
 }