[RFC PATCH v3 11/26] ext4: also mark extent as delalloc if it's been unwritten

From: Zhang Yi
Date: Fri Jan 26 2024 - 21:07:09 EST


From: Zhang Yi <yi.zhang@xxxxxxxxxx>

Mark extent as delalloc if it's been unwritten, this delalloc flag will
last until write back. It would be useful to indicate the map length
when writing data back after converting regular file's buffered write
path to iomap.

Signed-off-by: Zhang Yi <yi.zhang@xxxxxxxxxx>
---
fs/ext4/inode.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 44033828db44..9ac9bb548a4c 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1742,7 +1742,11 @@ static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
#ifdef ES_AGGRESSIVE_TEST
ext4_map_blocks_es_recheck(NULL, inode, map, &orig_map, 0);
#endif
- return retval;
+ if (ext4_es_is_delayed(&es) || ext4_es_is_written(&es))
+ return retval;
+
+ down_read(&EXT4_I(inode)->i_data_sem);
+ goto insert_extent;
}

/*
@@ -1770,9 +1774,11 @@ static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
inode->i_ino, retval, map->m_len);
WARN_ON(1);
}
-
+insert_extent:
status = map->m_flags & EXT4_MAP_UNWRITTEN ?
EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
+ if (status == EXTENT_STATUS_UNWRITTEN)
+ status |= EXTENT_STATUS_DELAYED;
ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
map->m_pblk, status);
up_read(&EXT4_I(inode)->i_data_sem);
--
2.39.2