Re: [PATCH v14 11/21] xfs: don't report dio_mem_align and dio_offset_align for fsverity files

On Tue, Aug 04, 2026 at 07:43:47PM +0200, Christoph Hellwig wrote:
> On Mon, Aug 03, 2026 at 10:08:01PM +0200, Andrey Albershteyn wrote:
> > Sashiko.dev reported that while fsverity files falls back to the
> > buffered IO for Direct I/O, they should not report non-zero values in
> > dio_mem_align and dio_offset_align, meaning it's not supported.
> 
> This doesn't make much sense to me.  If we didn't want to report
> we'd also want to not set STATX_DIOALIGN | STATX_DIO_READ_ALIGN.
> But in the end there is very little upside of this while adding
> extra special cases.

Zero values in the alignments are defined to mean that DIO is
unsupported; see statx(2).  It's right to do that here and also set
STATX_DIOALIGN | STATX_DIO_READ_ALIGN, as that explicitly reports that
DIO is unsupported.

Leaving the attribute flags unset would mean not reporting anything at
all, which could mean DIO either supported or unsupported.

Acked-by: Eric Biggers <[email protected]>

- Eric