Re: [PATCH 4/5] xfs: report the correct read/write dio alignment for reflinked inodes

Christoph Hellwig
2025-01-08T15:18:34Z

On Wed, Jan 08, 2025 at 10:13:02AM +0000, John Garry wrote:
> On 08/01/2025 08:55, Christoph Hellwig wrote:
>> @@ -580,9 +580,24 @@ xfs_report_dioalign(
>> struct xfs_buftarg *target = xfs_inode_buftarg(ip);
>> struct block_device *bdev = target->bt_bdev;
>> - stat->result_mask |= STATX_DIOALIGN;
>> + stat->result_mask |= STATX_DIOALIGN | STATX_DIO_READ_ALIGN;
>
> BTW, it would be a crappy userspace which can't handle fields which it did
> not ask for, e.g. asked for STATX_DIOALIGN, but got STATX_DIOALIGN and
> STATX_DIO_READ_ALIGN

Well, the space is marked for extension. I don't think there ever
was a requirement only fields asked for are reported, but if that
feels safer I could switch to that.