get:
Show a patch.

patch:
Update a patch.

put:
Update a patch.

GET /api/patches/818023/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 818023,
    "url": "http://patchwork.ozlabs.org/api/patches/818023/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/netdev/patch/111d95035f7cee64abab545c98e56c3013cb4979.1506297988.git.daniel@iogearbox.net/",
    "project": {
        "id": 7,
        "url": "http://patchwork.ozlabs.org/api/projects/7/?format=api",
        "name": "Linux network development",
        "link_name": "netdev",
        "list_id": "netdev.vger.kernel.org",
        "list_email": "netdev@vger.kernel.org",
        "web_url": null,
        "scm_url": null,
        "webscm_url": null,
        "list_archive_url": "",
        "list_archive_url_format": "",
        "commit_url_format": ""
    },
    "msgid": "<111d95035f7cee64abab545c98e56c3013cb4979.1506297988.git.daniel@iogearbox.net>",
    "list_archive_url": null,
    "date": "2017-09-25T00:25:55",
    "name": "[net-next,6/6] bpf, ixgbe: add meta data support",
    "commit_ref": null,
    "pull_url": null,
    "state": "accepted",
    "archived": true,
    "hash": "d91fd27d670d4380c6972f2d85802a35e01868a3",
    "submitter": {
        "id": 65705,
        "url": "http://patchwork.ozlabs.org/api/people/65705/?format=api",
        "name": "Daniel Borkmann",
        "email": "daniel@iogearbox.net"
    },
    "delegate": {
        "id": 34,
        "url": "http://patchwork.ozlabs.org/api/users/34/?format=api",
        "username": "davem",
        "first_name": "David",
        "last_name": "Miller",
        "email": "davem@davemloft.net"
    },
    "mbox": "http://patchwork.ozlabs.org/project/netdev/patch/111d95035f7cee64abab545c98e56c3013cb4979.1506297988.git.daniel@iogearbox.net/mbox/",
    "series": [
        {
            "id": 4860,
            "url": "http://patchwork.ozlabs.org/api/series/4860/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/netdev/list/?series=4860",
            "date": "2017-09-25T00:25:49",
            "name": "BPF metadata for direct access",
            "version": 1,
            "mbox": "http://patchwork.ozlabs.org/series/4860/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/patches/818023/comments/",
    "check": "pending",
    "checks": "http://patchwork.ozlabs.org/api/patches/818023/checks/",
    "tags": {},
    "related": [],
    "headers": {
        "Return-Path": "<netdev-owner@vger.kernel.org>",
        "X-Original-To": "patchwork-incoming@ozlabs.org",
        "Delivered-To": "patchwork-incoming@ozlabs.org",
        "Authentication-Results": "ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=netdev-owner@vger.kernel.org;\n\treceiver=<UNKNOWN>)",
        "Received": [
            "from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3y0lKH37Nmz9s82\n\tfor <patchwork-incoming@ozlabs.org>;\n\tMon, 25 Sep 2017 10:27:31 +1000 (AEST)",
            "(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S933279AbdIYA1S (ORCPT <rfc822;patchwork-incoming@ozlabs.org>);\n\tSun, 24 Sep 2017 20:27:18 -0400",
            "from www62.your-server.de ([213.133.104.62]:37246 \"EHLO\n\twww62.your-server.de\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S933078AbdIYA1I (ORCPT\n\t<rfc822;netdev@vger.kernel.org>); Sun, 24 Sep 2017 20:27:08 -0400",
            "from [85.7.161.218] (helo=localhost)\n\tby www62.your-server.de with esmtpsa\n\t(TLSv1.2:DHE-RSA-AES128-GCM-SHA256:128) (Exim 4.85_2)\n\t(envelope-from <daniel@iogearbox.net>)\n\tid 1dwHEp-0000IX-60; Mon, 25 Sep 2017 02:27:07 +0200"
        ],
        "From": "Daniel Borkmann <daniel@iogearbox.net>",
        "To": "davem@davemloft.net",
        "Cc": "alexei.starovoitov@gmail.com, john.fastabend@gmail.com,\n\tpeter.waskiewicz.jr@intel.com, jakub.kicinski@netronome.com,\n\tnetdev@vger.kernel.org, Daniel Borkmann <daniel@iogearbox.net>",
        "Subject": "[PATCH net-next 6/6] bpf, ixgbe: add meta data support",
        "Date": "Mon, 25 Sep 2017 02:25:55 +0200",
        "Message-Id": "<111d95035f7cee64abab545c98e56c3013cb4979.1506297988.git.daniel@iogearbox.net>",
        "X-Mailer": "git-send-email 1.9.3",
        "In-Reply-To": [
            "<cover.1506297988.git.daniel@iogearbox.net>",
            "<cover.1506297988.git.daniel@iogearbox.net>"
        ],
        "References": [
            "<cover.1506297988.git.daniel@iogearbox.net>",
            "<cover.1506297988.git.daniel@iogearbox.net>"
        ],
        "X-Authenticated-Sender": "daniel@iogearbox.net",
        "X-Virus-Scanned": "Clear (ClamAV 0.99.2/23869/Sun Sep 24 18:45:57 2017)",
        "Sender": "netdev-owner@vger.kernel.org",
        "Precedence": "bulk",
        "List-ID": "<netdev.vger.kernel.org>",
        "X-Mailing-List": "netdev@vger.kernel.org"
    },
    "content": "Implement support for transferring XDP meta data into skb for\nixgbe driver; before calling into the program, xdp.data_meta points\nto xdp.data, where on program return with pass verdict, we call\ninto skb_metadata_set().\n\nWe implement this for the default ixgbe_build_skb() variant. For the\nixgbe_construct_skb() that is used when legacy-rx buffer mananagement\nmode is turned on via ethtool, I found that XDP gets 0 headroom, so\nneither xdp_adjust_head() nor xdp_adjust_meta() can be used with this.\nJust add a comment with explanation for this operating mode.\n\nSigned-off-by: Daniel Borkmann <daniel@iogearbox.net>\nAcked-by: Alexei Starovoitov <ast@kernel.org>\nAcked-by: John Fastabend <john.fastabend@gmail.com>\n---\n drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 30 +++++++++++++++++++++++----\n 1 file changed, 26 insertions(+), 4 deletions(-)",
    "diff": "diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c\nindex 04bb03b..3942c62 100644\n--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c\n+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c\n@@ -2133,6 +2133,21 @@ static struct sk_buff *ixgbe_construct_skb(struct ixgbe_ring *rx_ring,\n #if L1_CACHE_BYTES < 128\n \tprefetch(xdp->data + L1_CACHE_BYTES);\n #endif\n+\t/* Note, we get here by enabling legacy-rx via:\n+\t *\n+\t *    ethtool --set-priv-flags <dev> legacy-rx on\n+\t *\n+\t * In this mode, we currently get 0 extra XDP headroom as\n+\t * opposed to having legacy-rx off, where we process XDP\n+\t * packets going to stack via ixgbe_build_skb(). The latter\n+\t * provides us currently with 192 bytes of headroom.\n+\t *\n+\t * For ixgbe_construct_skb() mode it means that the\n+\t * xdp->data_meta will always point to xdp->data, since\n+\t * the helper cannot expand the head. Should this ever\n+\t * change in future for legacy-rx mode on, then lets also\n+\t * add xdp->data_meta handling here.\n+\t */\n \n \t/* allocate a skb to store the frags */\n \tskb = napi_alloc_skb(&rx_ring->q_vector->napi, IXGBE_RX_HDR_SIZE);\n@@ -2165,6 +2180,7 @@ static struct sk_buff *ixgbe_build_skb(struct ixgbe_ring *rx_ring,\n \t\t\t\t       struct xdp_buff *xdp,\n \t\t\t\t       union ixgbe_adv_rx_desc *rx_desc)\n {\n+\tunsigned int metasize = xdp->data - xdp->data_meta;\n #if (PAGE_SIZE < 8192)\n \tunsigned int truesize = ixgbe_rx_pg_size(rx_ring) / 2;\n #else\n@@ -2174,10 +2190,14 @@ static struct sk_buff *ixgbe_build_skb(struct ixgbe_ring *rx_ring,\n #endif\n \tstruct sk_buff *skb;\n \n-\t/* prefetch first cache line of first page */\n-\tprefetch(xdp->data);\n+\t/* Prefetch first cache line of first page. If xdp->data_meta\n+\t * is unused, this points extactly as xdp->data, otherwise we\n+\t * likely have a consumer accessing first few bytes of meta\n+\t * data, and then actual data.\n+\t */\n+\tprefetch(xdp->data_meta);\n #if L1_CACHE_BYTES < 128\n-\tprefetch(xdp->data + L1_CACHE_BYTES);\n+\tprefetch(xdp->data_meta + L1_CACHE_BYTES);\n #endif\n \n \t/* build an skb to around the page buffer */\n@@ -2188,6 +2208,8 @@ static struct sk_buff *ixgbe_build_skb(struct ixgbe_ring *rx_ring,\n \t/* update pointers within the skb to store the data */\n \tskb_reserve(skb, xdp->data - xdp->data_hard_start);\n \t__skb_put(skb, xdp->data_end - xdp->data);\n+\tif (metasize)\n+\t\tskb_metadata_set(skb, metasize);\n \n \t/* record DMA address if this is the start of a chain of buffers */\n \tif (!ixgbe_test_staterr(rx_desc, IXGBE_RXD_STAT_EOP))\n@@ -2326,7 +2348,7 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,\n \t\tif (!skb) {\n \t\t\txdp.data = page_address(rx_buffer->page) +\n \t\t\t\t   rx_buffer->page_offset;\n-\t\t\txdp_set_data_meta_invalid(&xdp);\n+\t\t\txdp.data_meta = xdp.data;\n \t\t\txdp.data_hard_start = xdp.data -\n \t\t\t\t\t      ixgbe_rx_offset(rx_ring);\n \t\t\txdp.data_end = xdp.data + size;\n",
    "prefixes": [
        "net-next",
        "6/6"
    ]
}