On Wed, Feb 19, 2025 at 02:33:44PM -0800, Darrick J. Wong wrote:
> On Wed, Feb 19, 2025 at 12:50:42PM -0500, Brian Foster wrote:
> > DAX reads and writes flow through dax_iomap_iter(), which has one or
> > more subtleties in terms of how it processes a range vs. what is
> > specified in the iomap_iter. To keep things simple and remove the
> > dependency on iomap_iter() advances, convert a positive return from
> > dax_iomap_iter() to the new advance and status return semantics. The
> > advance can be pushed further down in future patches.
> >
> > Signed-off-by: Brian Foster <bfoster@xxxxxxxxxx>
> > Reviewed-by: Christoph Hellwig <hch@xxxxxx>
>
> Not sure why this and the next patch are split up but it's fsdax so meh.
> Reviewed-by: "Darrick J. Wong" <djwong@xxxxxxxxxx>
>
Heh.. mainly just out of caution and bisectability. The subsequent patch
took a bit of fighting for me to get right and this patch served as a
nice baseline to isolate changes in the DAX I/O path from the functional
iomap change, since this patch is relatively trivial.
Thanks for the reviews..
Brian
> --D
>
> > ---
> > fs/dax.c | 6 +++++-
> > 1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/fs/dax.c b/fs/dax.c
> > index 21b47402b3dc..296f5aa18640 100644
> > --- a/fs/dax.c
> > +++ b/fs/dax.c
> > @@ -1585,8 +1585,12 @@ dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
> > if (iocb->ki_flags & IOCB_NOWAIT)
> > iomi.flags |= IOMAP_NOWAIT;
> >
> > - while ((ret = iomap_iter(&iomi, ops)) > 0)
> > + while ((ret = iomap_iter(&iomi, ops)) > 0) {
> > iomi.processed = dax_iomap_iter(&iomi, iter);
> > + if (iomi.processed > 0)
> > + iomi.processed = iomap_iter_advance(&iomi,
> > + &iomi.processed);
> > + }
> >
> > done = iomi.pos - iocb->ki_pos;
> > iocb->ki_pos = iomi.pos;
> > --
> > 2.48.1
> >
> >
>
