[PATCH v6 04/31] ext4: set EXT4_MAP_NEW flag for delayed allocated blocks

[Zhang Yi]

From: Zhang Yi <yi.zhang@xxxxxxxxxx>

Set EXT4_MAP_NEW in ext4_da_map_blocks() to properly indicate that a
new delayed allocation block has been inserted, allowing callers to
distinguish newly created delayed extents from existing ones.

Currently, the buffer_head caller, ext4_da_get_block_prep(), does not
consume this flag. It intercepts EXT4_MAP_DELAYED and returns early, and
unconditionally calls set_buffer_new(bh) so EXT4_MAP_NEW is not used.
The flag is prepared for the iomap buffered I/O path added later.

Reported-by: Ojaswin Mujoo <ojaswin@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/linux-ext4/cc05c17d-163e-4251-b2c9-aa3a6f9555d7@xxxxxxxxxxxxxxx/
Signed-off-by: Zhang Yi <yi.zhang@xxxxxxxxxx>
---
 fs/ext4/inode.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 4fc0d331c49d..84991fe99071 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1990,7 +1990,7 @@ static int ext4_da_map_blocks(struct inode *inode, struct ext4_map_blocks *map)
 		}
 	}
 
-	map->m_flags |= EXT4_MAP_DELAYED;
+	map->m_flags |= EXT4_MAP_DELAYED | EXT4_MAP_NEW;
 	retval = ext4_insert_delayed_blocks(inode, map->m_lblk, map->m_len);
 	if (!retval)
 		map->m_seq = READ_ONCE(EXT4_I(inode)->i_es_seq);
-- 
2.52.0