Re: [PATCH v7 12/15] io_uring/zcrx: add io_recvzc request

[Mina Almasry <almasrymina@google.com>]

On Fri, Nov 1, 2024 at 2:16 PM Pavel Begunkov <asml.silence@gmail.com> wrote:
>
> On 11/1/24 20:11, Mina Almasry wrote:
> > On Tue, Oct 29, 2024 at 4:06 PM David Wei <dw@davidwei.uk> wrote:
> >>
> > ...
> >> +static void io_zcrx_get_buf_uref(struct net_iov *niov)
> >> +{
> >> +       atomic_long_add(IO_ZC_RX_UREF, &niov->pp_ref_count);
> >> +}
> >> +
> >
> > This is not specific to io_rcrx I think. Please rename this and put it
> > somewhere generic, like netmem.h.
> >
> > Then tcp_recvmsg_dmabuf can use the same helper instead of the very
> > ugly call it currently does:
> >
> > - atomic_long_inc(&niov->pp_ref_count);
> > + net_iov_pp_ref_get(niov, 1);
> >
> > Or something.
> >
> > In general I think io_uring code can do whatever it wants with the
> > io_uring specific bits in net_iov (everything under net_area_owner I
> > think), but please lets try to keep any code touching the generic
> > net_iov fields (pp_pagic, pp_ref_count, and others) in generic
> > helpers.
>
> I'm getting confused, io_uring shouldn't be touching these
> fields, but on the other hand should export net/ private
> netmem_priv.h and page_pool_priv.h and directly hard code a bunch
> of low level setup io_uring that is currently in page_pool.c
>

The only thing requested from this patch is to turn
io_zcrx_get_buf_uref into something more generic. I'm guessing your
confusion is following my other comments in "[PATCH v7 06/15] net:
page pool: add helper creating area from pages". Let me take a closer
look at my feedback there.

-- 
Thanks,
Mina