Re: [PATCH 2/5] io_uring: bpf: add io_uring_ctx setup for BPF into one list

[Ming Lei <ming.lei@redhat.com>]

On Tue, Dec 30, 2025 at 08:13:51PM -0500, Caleb Sander Mateos wrote:
> On Tue, Nov 4, 2025 at 8:22 AM Ming Lei <ming.lei@redhat.com> wrote:
> >
> > Add io_uring_ctx setup for BPF into one list, and prepare for syncing
> > bpf struct_ops register and un-register.
> >
> > Signed-off-by: Ming Lei <ming.lei@redhat.com>
> > ---
> >  include/linux/io_uring_types.h |  5 +++++
> >  include/uapi/linux/io_uring.h  |  5 +++++
> >  io_uring/bpf.c                 | 15 +++++++++++++++
> >  io_uring/io_uring.c            |  7 +++++++
> >  io_uring/io_uring.h            |  3 ++-
> >  io_uring/uring_bpf.h           | 11 +++++++++++
> >  6 files changed, 45 insertions(+), 1 deletion(-)
> >
> > diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h
> > index 92780764d5fa..d2e098c3fd2c 100644
> > --- a/include/linux/io_uring_types.h
> > +++ b/include/linux/io_uring_types.h
> > @@ -465,6 +465,11 @@ struct io_ring_ctx {
> >         struct io_mapped_region         ring_region;
> >         /* used for optimised request parameter and wait argument passing  */
> >         struct io_mapped_region         param_region;
> > +
> > +#ifdef CONFIG_IO_URING_BPF
> > +       /* added to uring_bpf_ctx_list */
> > +       struct list_head                bpf_node;
> > +#endif
> >  };
> >
> >  /*
> > diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
> > index b167c1d4ce6e..b8c49813b4e5 100644
> > --- a/include/uapi/linux/io_uring.h
> > +++ b/include/uapi/linux/io_uring.h
> > @@ -237,6 +237,11 @@ enum io_uring_sqe_flags_bit {
> >   */
> >  #define IORING_SETUP_SQE_MIXED         (1U << 19)
> >
> > +/*
> > + * Allow to submit bpf IO
> > + */
> > +#define IORING_SETUP_BPF               (1U << 20)
> 
> Is the setup flag really necessary? It doesn't look like there's much
> overhead to allowing BPF programs to be used on any io_ring_ctx, so I
> would be inclined to avoid needing to set an additional flag to use
> it.

It is used for dealing with unregistering & registering bpf prog vs. handling IO.



Thanks,
Ming