bpf.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Toke Høiland-Jørgensen" <toke@redhat.com>
To: Lorenz Bauer <lmb@cloudflare.com>, Jakub Kicinski <kuba@kernel.org>
Cc: Lorenzo Bianconi <lorenzo@kernel.org>, bpf <bpf@vger.kernel.org>,
	Networking <netdev@vger.kernel.org>,
	Lorenzo Bianconi <lorenzo.bianconi@redhat.com>,
	"David S . Miller" <davem@davemloft.net>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	shayagr@amazon.com, John Fastabend <john.fastabend@gmail.com>,
	David Ahern <dsahern@kernel.org>,
	Jesper Dangaard Brouer <brouer@redhat.com>,
	Eelco Chaudron <echaudro@redhat.com>,
	Jason Wang <jasowang@redhat.com>,
	Alexander Duyck <alexander.duyck@gmail.com>,
	Saeed Mahameed <saeed@kernel.org>,
	Maciej Fijalkowski <maciej.fijalkowski@intel.com>,
	"Karlsson, Magnus" <magnus.karlsson@intel.com>,
	tirthendu.sarkar@intel.com
Subject: Re: [PATCH v14 bpf-next 00/18] mvneta: introduce XDP multi-buffer support
Date: Wed, 29 Sep 2021 14:10:20 +0200	[thread overview]
Message-ID: <87v92jinv7.fsf@toke.dk> (raw)
In-Reply-To: <CACAyw9-8t8RpJgJUTd7u6bOLnJ1xQsgK7z37QrL9T1FUaJ7WNQ@mail.gmail.com>

Lorenz Bauer <lmb@cloudflare.com> writes:

> On Thu, 16 Sept 2021 at 18:47, Jakub Kicinski <kuba@kernel.org> wrote:
>>
>> Won't applications end up building something like skb_header_pointer()
>> based on bpf_xdp_adjust_data(), anyway? In which case why don't we
>> provide them what they need?
>>
>> say:
>>
>> void *xdp_mb_pointer(struct xdp_buff *xdp_md, u32 flags,
>>                      u32 offset, u32 len, void *stack_buf)
>>
>> flags and offset can be squashed into one u64 as needed. Helper returns
>> pointer to packet data, either real one or stack_buf. Verifier has to
>> be taught that the return value is NULL or a pointer which is safe with
>> offsets up to @len.
>>
>> If the reason for access is write we'd also need:
>>
>> void *xdp_mb_pointer_flush(struct xdp_buff *xdp_md, u32 flags,
>>                            u32 offset, u32 len, void *stack_buf)
>
> Yes! This would be so much better than bpf_skb_load/store_bytes(),
> especially if we can use it for both XDP and skb contexts as stated
> elsewhere in this thread.

Alright. Let's see if we can go this route, then :)

-Toke


  reply	other threads:[~2021-09-29 12:10 UTC|newest]

Thread overview: 58+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-10 16:14 [PATCH v14 bpf-next 00/18] mvneta: introduce XDP multi-buffer support Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 01/18] net: skbuff: add size metadata to skb_shared_info for xdp Lorenzo Bianconi
2021-09-10 16:18   ` Jesper Dangaard Brouer
2021-09-10 16:14 ` [PATCH v14 bpf-next 02/18] xdp: introduce flags field in xdp_buff/xdp_frame Lorenzo Bianconi
2021-09-10 16:19   ` Jesper Dangaard Brouer
2021-09-10 16:14 ` [PATCH v14 bpf-next 03/18] net: mvneta: update mb bit before passing the xdp buffer to eBPF layer Lorenzo Bianconi
2021-09-20  8:25   ` Shay Agroskin
2021-09-20  8:37     ` Lorenzo Bianconi
2021-09-20  8:45       ` Shay Agroskin
2021-09-20  9:00         ` Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 04/18] net: mvneta: simplify mvneta_swbm_add_rx_fragment management Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 05/18] net: xdp: add xdp_update_skb_shared_info utility routine Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 06/18] net: marvell: rely on " Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 07/18] xdp: add multi-buff support to xdp_return_{buff/frame} Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 08/18] net: mvneta: add multi buffer support to XDP_TX Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 09/18] net: mvneta: enable jumbo frames for XDP Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 10/18] bpf: add multi-buff support to the bpf_xdp_adjust_tail() API Lorenzo Bianconi
2021-09-16 16:55   ` Jakub Kicinski
2021-09-17 10:02     ` Lorenzo Bianconi
2021-09-17 13:03       ` Jakub Kicinski
2021-09-10 16:14 ` [PATCH v14 bpf-next 11/18] bpf: introduce bpf_xdp_get_buff_len helper Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 12/18] bpf: add multi-buffer support to xdp copy helpers Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 13/18] bpf: move user_size out of bpf_test_init Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 14/18] bpf: introduce multibuff support to bpf_prog_test_run_xdp() Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 15/18] bpf: test_run: add xdp_shared_info pointer in bpf_test_finish signature Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 16/18] bpf: update xdp_adjust_tail selftest to include multi-buffer Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 17/18] net: xdp: introduce bpf_xdp_adjust_data helper Lorenzo Bianconi
2021-09-10 16:14 ` [PATCH v14 bpf-next 18/18] bpf: add bpf_xdp_adjust_data selftest Lorenzo Bianconi
2021-09-16 16:55 ` [PATCH v14 bpf-next 00/18] mvneta: introduce XDP multi-buffer support Jakub Kicinski
2021-09-17 14:51   ` Lorenzo Bianconi
2021-09-17 18:33     ` Jakub Kicinski
2021-09-17 18:43       ` Alexei Starovoitov
2021-09-17 19:00         ` Jakub Kicinski
2021-09-17 19:10           ` Alexei Starovoitov
2021-09-17 22:07             ` John Fastabend
2021-09-18 11:53               ` Toke Høiland-Jørgensen
2021-09-20 18:02                 ` Jakub Kicinski
2021-09-20 21:01                   ` Toke Høiland-Jørgensen
2021-09-20 21:25                     ` Jakub Kicinski
2021-09-20 22:44                       ` Toke Høiland-Jørgensen
2021-09-21 10:03                         ` Eelco Chaudron
2021-09-28 11:48                           ` Magnus Karlsson
2021-09-29 10:36                         ` Lorenz Bauer
2021-09-29 12:25                           ` Toke Høiland-Jørgensen
2021-09-29 12:32                             ` Lorenz Bauer
2021-09-29 17:48                             ` Jakub Kicinski
2021-09-29 17:46                           ` Jakub Kicinski
2021-09-29 10:41   ` Lorenz Bauer
2021-09-29 12:10     ` Toke Høiland-Jørgensen [this message]
2021-09-29 12:38       ` Lorenz Bauer
2021-09-29 18:54         ` Alexei Starovoitov
2021-09-29 19:22           ` Jakub Kicinski
2021-09-29 20:39             ` Toke Høiland-Jørgensen
2021-10-01  9:03               ` Lorenzo Bianconi
2021-10-01 18:35                 ` Jakub Kicinski
2021-10-06  9:32                   ` Lorenzo Bianconi
2021-10-06 10:08                     ` Eelco Chaudron
2021-10-06 12:15                       ` Lorenzo Bianconi

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=87v92jinv7.fsf@toke.dk \
    --to=toke@redhat.com \
    --cc=alexander.duyck@gmail.com \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=brouer@redhat.com \
    --cc=daniel@iogearbox.net \
    --cc=davem@davemloft.net \
    --cc=dsahern@kernel.org \
    --cc=echaudro@redhat.com \
    --cc=jasowang@redhat.com \
    --cc=john.fastabend@gmail.com \
    --cc=kuba@kernel.org \
    --cc=lmb@cloudflare.com \
    --cc=lorenzo.bianconi@redhat.com \
    --cc=lorenzo@kernel.org \
    --cc=maciej.fijalkowski@intel.com \
    --cc=magnus.karlsson@intel.com \
    --cc=netdev@vger.kernel.org \
    --cc=saeed@kernel.org \
    --cc=shayagr@amazon.com \
    --cc=tirthendu.sarkar@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).