On Fri, 13 Jun 2025, Chuck Lever wrote:
> From: Chuck Lever <chuck.lever@xxxxxxxxxx>
>
> Refactor: Enable the use of RWF_ flags to control individual I/O
> operations.
RWF_ flags such as .... ???
I'm guessing RWF_DIRECT and maybe RWF_NOWAIT based on the earlier
conversation. Might be useful to provide this as explicit motivation.
But seeing they will be passed to kiocb_set_rw_flags(), shouldn't we be
talking about the IOCB_ versions of the flags? The only caller of
kiocb_set_rw_flags() I can find which doesn't pass zero is aio_prep_rw()
and it uses the IOCB_ versions.
And should we be changing the vfs_iter_write() to vfs_iocb_iter_write()
too, just for consistency?
>
> Suggested-by: Christoph Hellwig <hch@xxxxxxxxxxxxx>
> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Reviewed-by: NeilBrown <neil@xxxxxxxxxx>
3 more callers to go and vfs_iter_read() could be discarded.
NeilBrown
> ---
> fs/nfsd/vfs.c | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
> index cd689df2ca5d..f20bacd9b224 100644
> --- a/fs/nfsd/vfs.c
> +++ b/fs/nfsd/vfs.c
> @@ -1086,10 +1086,18 @@ __be32 nfsd_iter_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
> {
> unsigned long v, total;
> struct iov_iter iter;
> - loff_t ppos = offset;
> + struct kiocb kiocb;
> ssize_t host_err;
> size_t len;
>
> + init_sync_kiocb(&kiocb, file);
> + host_err = kiocb_set_rw_flags(&kiocb, 0, READ);
> + if (host_err) {
> + *count = 0;
> + goto out;
> + }
> + kiocb.ki_pos = offset;
> +
> v = 0;
> total = *count;
> while (total) {
> @@ -1104,7 +1112,8 @@ __be32 nfsd_iter_read(struct svc_rqst *rqstp, struct svc_fh *fhp,
>
> trace_nfsd_read_vector(rqstp, fhp, offset, *count);
> iov_iter_bvec(&iter, ITER_DEST, rqstp->rq_bvec, v, *count);
> - host_err = vfs_iter_read(file, &iter, &ppos, 0);
> + host_err = vfs_iocb_iter_read(file, &kiocb, &iter);
> +out:
> return nfsd_finish_read(rqstp, fhp, file, offset, count, eof, host_err);
> }
>
> --
> 2.49.0
>
>
