From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by mail.toke.dk (Postfix) with ESMTPS id 3035C982C48 for ; Tue, 28 Jun 2022 21:49:22 +0200 (CEST) Authentication-Results: mail.toke.dk; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=KHllPRaF DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1656445762; x=1687981762; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=SqWbOCdnhWLJ6BpjYS5/roLulPLkxRjJFV89S0QmGTs=; b=KHllPRaFLYswjOM/Ue7qTcY2wj7Pp9dBGVKCrA76vH/0EEIisH1FYeln vvpp+cALViecZjS5gnNrwh+2+uQZI/eVSG/1eMKpj2y+xAtAfxtJL2VtI jBOEZTXyhAxKhnsKjCBd1YW+q9nKZKX01hE54FWw3xN+pxpq81UbC3Kfs eVXrV6vavGsFwll1jbuYyQtXd87rniHUqUsxSN7d2MauYamrPedYQjydy Whg9lOARnnstz6lcbTyjVYoB6izvEzBEtTgK7EeZ/GKNP8z66eBT6nCDt 35KXckZtQonYOFvxsOxLNrlcpu+nqziiNyo+RTtSsVHeUR1zwp45h4AEC g==; X-IronPort-AV: E=McAfee;i="6400,9594,10392"; a="343523172" X-IronPort-AV: E=Sophos;i="5.92,229,1650956400"; d="scan'208";a="343523172" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Jun 2022 12:49:12 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.92,229,1650956400"; d="scan'208";a="693250944" Received: from irvmail001.ir.intel.com ([10.43.11.63]) by fmsmga002.fm.intel.com with ESMTP; 28 Jun 2022 12:49:07 -0700 Received: from newjersey.igk.intel.com (newjersey.igk.intel.com [10.102.20.203]) by irvmail001.ir.intel.com (8.14.3/8.13.6/MailSET/Hub) with ESMTP id 25SJmr99022013; Tue, 28 Jun 2022 20:49:06 +0100 From: Alexander Lobakin To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Date: Tue, 28 Jun 2022 21:47:29 +0200 Message-Id: <20220628194812.1453059-10-alexandr.lobakin@intel.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220628194812.1453059-1-alexandr.lobakin@intel.com> References: <20220628194812.1453059-1-alexandr.lobakin@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID-Hash: I545WQJ2PVUA3V2FCTBA3DNFW42ESSO7 X-Message-ID-Hash: I545WQJ2PVUA3V2FCTBA3DNFW42ESSO7 X-MailFrom: alexandr.lobakin@intel.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: Alexander Lobakin , Larysa Zaremba , Michal Swiatkowski , Jesper Dangaard Brouer , =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= , Magnus Karlsson , Maciej Fijalkowski , Jonathan Lemon , Toke Hoiland-Jorgensen , Lorenzo Bianconi , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Jesse Brandeburg , John Fastabend , Yajun Deng , Willem de Bruijn , bpf@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, xdp-hints@xdp-project.net X-Mailman-Version: 3.3.5 Precedence: list Subject: [xdp-hints] [PATCH RFC bpf-next 09/52] net, xdp: add ability to specify BTF ID for XDP metadata List-Id: XDP hardware hints design discussion Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: Add the UAPI and the corresponding kernel part to be able to specify the BTF ID of the format which the drivers should compose metadata in (if supported). A driver might be able to provide XDP metadata in different formats, e.g. the generic one and one or several custom (with some non-universal data from DMA descriptors etc.). In this case, a BPF loader program will specify the wanted BTF ID and then BPF and AF_XDP programs will be expecting this format in XDP metadata and will be comparing different BTF IDs against the one that will be put in front of a frame. The BTF ID can be set and updated via both BPF link and rtnetlink (the %IFLA_XDP_BTF_ID attribute) interfaces, got via &bpf_link_info and is being passed to the drivers inside &netdev_bpf. net_device_ops::ndo_bpf() is now being called not only when @new_prog != @old_prog, but also when @new_prog == @old_prog && @new_btf_id != @btf_id, so the drivers should be able to handle such cases. Signed-off-by: Alexander Lobakin --- include/linux/netdevice.h | 2 ++ include/net/xdp.h | 1 + include/uapi/linux/bpf.h | 12 ++++++++++++ include/uapi/linux/if_link.h | 1 + kernel/bpf/syscall.c | 2 +- net/bpf/core.c | 1 + net/bpf/dev.c | 26 +++++++++++++++++++++++--- net/core/rtnetlink.c | 6 ++++++ tools/include/uapi/linux/bpf.h | 12 ++++++++++++ tools/include/uapi/linux/if_link.h | 1 + 10 files changed, 60 insertions(+), 4 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 1e342c285f48..2218c1901daf 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -985,6 +985,7 @@ struct netdev_bpf { /* XDP_SETUP_PROG */ struct { u32 flags; + u64 btf_id; struct bpf_prog *prog; struct netlink_ext_ack *extack; }; @@ -3852,6 +3853,7 @@ struct xdp_install_args { struct net_device *dev; struct netlink_ext_ack *extack; u32 flags; + u64 btf_id; }; DECLARE_STATIC_KEY_FALSE(generic_xdp_needed_key); diff --git a/include/net/xdp.h b/include/net/xdp.h index 04c852c7a77f..13133c7493bc 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -400,6 +400,7 @@ static inline bool xdp_metalen_invalid(unsigned long metalen) struct xdp_attachment_info { struct bpf_prog *prog; + u64 btf_id; u32 flags; }; diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index e81362891596..c67ddb78915d 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1499,6 +1499,10 @@ union bpf_attr { */ __u64 cookie; } tracing; + struct { + /* target metadata BTF + type ID */ + __aligned_u64 btf_id; + } xdp; }; } link_create; @@ -1510,6 +1514,12 @@ union bpf_attr { /* expected link's program fd; is specified only if * BPF_F_REPLACE flag is set in flags */ __u32 old_prog_fd; + union { + struct { + /* new target metadata BTF + type ID */ + __aligned_u64 new_btf_id; + } xdp; + }; } link_update; struct { @@ -6138,6 +6148,8 @@ struct bpf_link_info { } netns; struct { __u32 ifindex; + __u32 :32; + __aligned_u64 btf_id; } xdp; }; } __attribute__((aligned(8))); diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index 5f58dcfe2787..73cdcc86875e 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -1307,6 +1307,7 @@ enum { IFLA_XDP_SKB_PROG_ID, IFLA_XDP_HW_PROG_ID, IFLA_XDP_EXPECTED_FD, + IFLA_XDP_BTF_ID, __IFLA_XDP_MAX, }; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index f7a674656067..2e86cfeae10f 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -4575,7 +4575,7 @@ static int link_create(union bpf_attr *attr, bpfptr_t uattr) return ret; } -#define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd +#define BPF_LINK_UPDATE_LAST_FIELD link_update.xdp.new_btf_id static int link_update(union bpf_attr *attr) { diff --git a/net/bpf/core.c b/net/bpf/core.c index fbb72792320a..e5abd5a64df7 100644 --- a/net/bpf/core.c +++ b/net/bpf/core.c @@ -552,6 +552,7 @@ void xdp_attachment_setup(struct xdp_attachment_info *info, if (info->prog) bpf_prog_put(info->prog); info->prog = bpf->prog; + info->btf_id = bpf->btf_id; info->flags = bpf->flags; } EXPORT_SYMBOL_GPL(xdp_attachment_setup); diff --git a/net/bpf/dev.c b/net/bpf/dev.c index 7df42bb886ad..e96986220126 100644 --- a/net/bpf/dev.c +++ b/net/bpf/dev.c @@ -273,6 +273,7 @@ struct bpf_xdp_link { struct bpf_link link; struct net_device *dev; /* protected by rtnl_lock, no refcnt held */ int flags; + u64 btf_id; }; typedef int (*bpf_op_t)(struct net_device *dev, struct netdev_bpf *bpf); @@ -357,8 +358,13 @@ static int dev_xdp_install(const struct xdp_install_args *args, struct netdev_bpf xdp; int err; + /* BTF ID must not be set when uninstalling the program */ + if (!prog && args->btf_id) + return -EINVAL; + memset(&xdp, 0, sizeof(xdp)); xdp.command = mode == XDP_MODE_HW ? XDP_SETUP_PROG_HW : XDP_SETUP_PROG; + xdp.btf_id = args->btf_id; xdp.extack = args->extack; xdp.flags = args->flags; xdp.prog = prog; @@ -517,8 +523,11 @@ static int dev_xdp_attach(const struct xdp_install_args *args, } } - /* don't call drivers if the effective program didn't change */ - if (new_prog != cur_prog) { + /* don't call drivers if the effective program or BTF ID didn't change. + * If @link == %NULL, we don't know the old value, so the only thing we + * can do is to call installing unconditionally + */ + if (new_prog != cur_prog || !link || args->btf_id != link->btf_id) { bpf_op = dev_xdp_bpf_op(dev, mode); if (!bpf_op) { NL_SET_ERR_MSG(extack, "Underlying driver does not support XDP in native mode"); @@ -545,6 +554,7 @@ static int dev_xdp_attach_link(struct bpf_xdp_link *link) struct xdp_install_args args = { .dev = link->dev, .flags = link->flags, + .btf_id = link->btf_id, }; return dev_xdp_attach(&args, link, NULL, NULL); @@ -606,13 +616,16 @@ static void bpf_xdp_link_show_fdinfo(const struct bpf_link *link, { struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); u32 ifindex = 0; + u64 btf_id; rtnl_lock(); if (xdp_link->dev) ifindex = xdp_link->dev->ifindex; + btf_id = xdp_link->btf_id; rtnl_unlock(); seq_printf(seq, "ifindex:\t%u\n", ifindex); + seq_printf(seq, "btf_id:\t0x%llx\n", btf_id); } static int bpf_xdp_link_fill_link_info(const struct bpf_link *link, @@ -620,13 +633,16 @@ static int bpf_xdp_link_fill_link_info(const struct bpf_link *link, { struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link); u32 ifindex = 0; + u64 btf_id; rtnl_lock(); if (xdp_link->dev) ifindex = xdp_link->dev->ifindex; + btf_id = xdp_link->btf_id; rtnl_unlock(); info->xdp.ifindex = ifindex; + info->xdp.btf_id = btf_id; return 0; } @@ -639,6 +655,7 @@ static int bpf_xdp_link_update(struct bpf_link *link, struct xdp_install_args args = { .dev = xdp_link->dev, .flags = xdp_link->flags, + .btf_id = attr->link_update.xdp.new_btf_id, }; enum bpf_xdp_mode mode; bpf_op_t bpf_op; @@ -663,7 +680,7 @@ static int bpf_xdp_link_update(struct bpf_link *link, goto out_unlock; } - if (old_prog == new_prog) { + if (old_prog == new_prog && args.btf_id == xdp_link->btf_id) { /* no-op, don't disturb drivers */ bpf_prog_put(new_prog); goto out_unlock; @@ -678,6 +695,8 @@ static int bpf_xdp_link_update(struct bpf_link *link, old_prog = xchg(&link->prog, new_prog); bpf_prog_put(old_prog); + xdp_link->btf_id = args.btf_id; + out_unlock: rtnl_unlock(); return err; @@ -716,6 +735,7 @@ int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog) bpf_link_init(&link->link, BPF_LINK_TYPE_XDP, &bpf_xdp_link_lops, prog); link->dev = dev; link->flags = attr->link_create.flags; + link->btf_id = attr->link_create.xdp.btf_id; err = bpf_link_prime(&link->link, &link_primer); if (err) { diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 5b06ded689b2..a30723b0e50c 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1979,6 +1979,7 @@ static const struct nla_policy ifla_xdp_policy[IFLA_XDP_MAX + 1] = { [IFLA_XDP_ATTACHED] = { .type = NLA_U8 }, [IFLA_XDP_FLAGS] = { .type = NLA_U32 }, [IFLA_XDP_PROG_ID] = { .type = NLA_U32 }, + [IFLA_XDP_BTF_ID] = { .type = NLA_U64 }, }; static const struct rtnl_link_ops *linkinfo_to_kind_ops(const struct nlattr *nla) @@ -2962,6 +2963,7 @@ static int do_setlink(const struct sk_buff *skb, if (tb[IFLA_XDP]) { struct nlattr *xdp[IFLA_XDP_MAX + 1]; u32 xdp_flags = 0; + u64 btf_id = 0; err = nla_parse_nested_deprecated(xdp, IFLA_XDP_MAX, tb[IFLA_XDP], @@ -2986,10 +2988,14 @@ static int do_setlink(const struct sk_buff *skb, } } + if (xdp[IFLA_XDP_BTF_ID]) + btf_id = nla_get_u64(xdp[IFLA_XDP_BTF_ID]); + if (xdp[IFLA_XDP_FD]) { struct xdp_install_args args = { .dev = dev, .extack = extack, + .btf_id = btf_id, .flags = xdp_flags, }; int expected_fd = -1; diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index e81362891596..c67ddb78915d 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1499,6 +1499,10 @@ union bpf_attr { */ __u64 cookie; } tracing; + struct { + /* target metadata BTF + type ID */ + __aligned_u64 btf_id; + } xdp; }; } link_create; @@ -1510,6 +1514,12 @@ union bpf_attr { /* expected link's program fd; is specified only if * BPF_F_REPLACE flag is set in flags */ __u32 old_prog_fd; + union { + struct { + /* new target metadata BTF + type ID */ + __aligned_u64 new_btf_id; + } xdp; + }; } link_update; struct { @@ -6138,6 +6148,8 @@ struct bpf_link_info { } netns; struct { __u32 ifindex; + __u32 :32; + __aligned_u64 btf_id; } xdp; }; } __attribute__((aligned(8))); diff --git a/tools/include/uapi/linux/if_link.h b/tools/include/uapi/linux/if_link.h index b339bf2196ca..68b126678dc8 100644 --- a/tools/include/uapi/linux/if_link.h +++ b/tools/include/uapi/linux/if_link.h @@ -1212,6 +1212,7 @@ enum { IFLA_XDP_SKB_PROG_ID, IFLA_XDP_HW_PROG_ID, IFLA_XDP_EXPECTED_FD, + IFLA_XDP_BTF_ID, __IFLA_XDP_MAX, }; -- 2.36.1