On Wed 05-02-20 14:15:58, Jeff Moyer wrote:
> fstests generic/471 reports a failure when run with MOUNT_OPTIONS="-o
> dax". The reason is that the initial pwrite to an empty file with the
> RWF_NOWAIT flag set does not return -EAGAIN. It turns out that
> dax_iomap_rw doesn't pass that flag through to iomap_apply.
>
> With this patch applied, generic/471 passes for me.
>
> Signed-off-by: Jeff Moyer <jmoyer@xxxxxxxxxx>
The patch looks good to me. You can add:
Reviewed-by: Jan Kara <jack@xxxxxxx>
BTW, I've just noticed ext4 seems to be buggy in this regard and even this
patch doesn't fix it. So I guess you've been using XFS for testing this?
Honza
> diff --git a/fs/dax.c b/fs/dax.c
> index 1f1f0201cad1..0b0d8819cb1b 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -1207,6 +1207,9 @@ dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
> lockdep_assert_held(&inode->i_rwsem);
> }
>
> + if (iocb->ki_flags & IOCB_NOWAIT)
> + flags |= IOMAP_NOWAIT;
> +
> while (iov_iter_count(iter)) {
> ret = iomap_apply(inode, pos, iov_iter_count(iter), flags, ops,
> iter, dax_iomap_actor);
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
