diff options
| author | Zhang Yi <yi.zhang@huawei.com> | 2026-01-05 09:45:21 +0800 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2026-01-19 22:28:30 -0500 |
| commit | 5ca28af074ad506c95a8f86a5d260562f3caa39b (patch) | |
| tree | 61d456d7075bc5da91eb8fa56bce53fcc7987520 | |
| parent | 8bd1f257af1c21d34f8758f4e36854970e1dc2f5 (diff) | |
ext4: simplify the mapping query logic in ext4_iomap_begin()
In the write path mapping check of ext4_iomap_begin(), the return value
'ret' should never greater than orig_mlen. If 'ret' equals 'orig_mlen',
it can be returned directly without checking IOMAP_ATOMIC.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/20260105014522.1937690-7-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
| -rw-r--r-- | fs/ext4/inode.c | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index f346302709b9..d914f612da10 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3812,17 +3812,19 @@ static int ext4_iomap_begin(struct inode *inode, loff_t offset, loff_t length, if (offset + length <= i_size_read(inode)) { ret = ext4_map_blocks(NULL, inode, &map, 0); /* - * For atomic writes the entire requested length should - * be mapped. For DAX we convert extents to initialized - * ones before copying the data, otherwise we do it - * after I/O so there's no need to call into - * ext4_iomap_alloc(). + * For DAX we convert extents to initialized ones before + * copying the data, otherwise we do it after I/O so + * there's no need to call into ext4_iomap_alloc(). */ if ((map.m_flags & EXT4_MAP_MAPPED) || (!(flags & IOMAP_DAX) && (map.m_flags & EXT4_MAP_UNWRITTEN))) { - if ((!(flags & IOMAP_ATOMIC) && ret > 0) || - (flags & IOMAP_ATOMIC && ret >= orig_mlen)) + /* + * For atomic writes the entire requested + * length should be mapped. + */ + if (ret == orig_mlen || + (!(flags & IOMAP_ATOMIC) && ret > 0)) goto out; } map.m_len = orig_mlen; |