On 2024/7/18 10:41, Gao Xiang wrote:
On 2024/7/17 14:34, Hongbo Li wrote:
On 2024/7/17 10:00, Gao Xiang wrote:
Hi,
On 2024/7/16 20:45, Hongbo Li wrote:
Add support for STATX_DIOALIGN to erofs, so that direct I/O
alignment restrictions are exposed to userspace in a generic
way.
[Before]
```
./statx_test /mnt/erofs/testfile
statx(/mnt/erofs/testfile) = 0
dio mem align:0
dio offset align:0
```
[After]
```
./statx_test /mnt/erofs/testfile
statx(/mnt/erofs/testfile) = 0
dio mem align:512
dio offset align:512
```
Signed-off-by: Hongbo Li <lihongb...@huawei.com>
---
fs/erofs/inode.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index 5f6439a63af7..9325a6f0058a 100644
--- a/fs/erofs/inode.c
+++ b/fs/erofs/inode.c
@@ -342,6 +342,25 @@ int erofs_getattr(struct mnt_idmap *idmap,
const struct path *path,
stat->attributes_mask |= (STATX_ATTR_COMPRESSED |
STATX_ATTR_IMMUTABLE);
+ /*
+ * Return the DIO alignment restrictions if requested.
+ *
+ * In erofs, STATX_DIOALIGN is not supported in ondemand mode and
+ * the compressed file, so in these cases we report no DIO
support.
+ */
+ if ((request_mask & STATX_DIOALIGN) && S_ISREG(inode->i_mode)) {
+ stat->result_mask |= STATX_DIOALIGN;
+ if (!erofs_is_fscache_mode(inode->i_sb) &&
+ !erofs_inode_is_data_compressed(EROFS_I(inode)->datalayout)) {
+ struct block_device *bdev = inode->i_sb->s_bdev;
+ unsigned int bsize = (bdev) ?
bdev_logical_block_size(bdev) :
+ i_blocksize(inode);
I guess in this way you could always use
stat->dio_mem_align = bdev_logical_block_size(bdev);
stat->dio_offset_align = stat->dio_mem_align;
? since bdev won't be NULL.
Yeah, only the EROFS_FS_ONDEMAND config is on, the s_bdev can be NULL.
Would you mind sending a v2 to fix this? At least, s_bdev is always
non-NULL currently.
I could apply this for this cycle.
I'm working on ondemand direct io mode. This will affect the
STATX_DIOALIGN result for erofs_is_fscache_mode case (.ie the
dio_mem_align is i_blocksize(inode) in erofs over fscache). Should we
apply this first and then modify it after the direct io is supported in
ondemand erofs?
Thanks,
Hongbo
Thanks,
Gao Xiang
Thanks,
Hongbo
Otherwise it looks good to me.
Thanks,
Gao Xiang
