From nobody Mon Feb 9 04:15:24 2026 Received: from out-178.mta0.migadu.com (out-178.mta0.migadu.com [91.218.175.178]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 22E9239281A for ; Wed, 4 Feb 2026 08:58:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.178 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770195490; cv=none; b=uGbnLqlqI3Rlahv4e710RfS7bYcCw6C+Yfq9+LH0oRgeC9+FYoijvVpJEWv1Nk6u2mESIT9/95lMkDfmhTxONP/nvnyBd3PwRexYWTU//tPUQFwaxihD8zFYMgCtLw+k2UNgqTOh3lTepEbTA8CGTHeCzTetmC1P3T2p/YVeJwc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770195490; c=relaxed/simple; bh=OGLI1S2l0PmNr2S4bsYnKqfqSXB+2A+DsfQrV5CIDWU=; h=From:To:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Y6f7tVwOd5l+GjyXHt92L34JQ9thSL34PKUs4KYoDdYdvG5fyU9dwQZwgGDZySVTJCfRBfFAad5YoejqiZoBIoZgwsnzcBBXDXwal1/ZF+OVkSqLdTVygv6SeNd1FSZgD+H7Un7fG05+gat0j0Hrx3ZTIoTyVNKT/WP8GMei9OQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=mV3XNp/7; arc=none smtp.client-ip=91.218.175.178 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="mV3XNp/7" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1770195487; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=FOthmRQx1S9k8S+lynuRz8PEGmhPgopf4vkxZNGup6E=; b=mV3XNp/73bTVDtA9nTQzugSdDlG72262JLw+h4pV2qzdM4DgjA/yBGClRKkVprrgxaQ1Sw 7JeS7rsWaPNRPzIj8reSrlzFsZ22dzA9SpkP4Lg42lRkGDImXnDj9Y4VrKO9coVXlldD9G ZzK8mNhu6T0VeQozaTgcLOVvCMUz8C4= From: Hui Zhu To: Andrew Morton , Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Peter Zijlstra , Miguel Ojeda , Nathan Chancellor , Kees Cook , Tejun Heo , Jeff Xu , mkoutny@suse.com, Jan Hendrik Farr , Christian Brauner , Randy Dunlap , Brian Gerst , Masahiro Yamada , davem@davemloft.net, Jakub Kicinski , Jesper Dangaard Brouer , JP Kobryn , Willem de Bruijn , Jason Xing , Paul Chaignon , Anton Protopopov , Amery Hung , Chen Ridong , Lance Yang , Jiayuan Chen , linux-kernel@vger.kernel.org, linux-mm@kvack.org, cgroups@vger.kernel.org, bpf@vger.kernel.org, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: [RFC PATCH bpf-next v6 05/12] libbpf: introduce bpf_map__attach_struct_ops_opts() Date: Wed, 4 Feb 2026 16:56:26 +0800 Message-ID: <8b9d7d9485c627dc05cdeb6863abd5a1c81c95ec.1770194182.git.zhuhui@kylinos.cn> In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset="utf-8" From: Roman Gushchin Introduce bpf_map__attach_struct_ops_opts(), an extended version of bpf_map__attach_struct_ops(), which takes additional struct bpf_struct_ops_opts argument. struct bpf_struct_ops_opts has the relative_fd member, which allows to pass an additional file descriptor argument. It can be used to attach struct ops maps to cgroups. Signed-off-by: Roman Gushchin --- tools/lib/bpf/bpf.c | 8 ++++++++ tools/lib/bpf/libbpf.c | 18 ++++++++++++++++-- tools/lib/bpf/libbpf.h | 14 ++++++++++++++ tools/lib/bpf/libbpf.map | 1 + 4 files changed, 39 insertions(+), 2 deletions(-) diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 5846de364209..84a53c594f48 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -884,6 +884,14 @@ int bpf_link_create(int prog_fd, int target_fd, if (!OPTS_ZEROED(opts, cgroup)) return libbpf_err(-EINVAL); break; + case BPF_STRUCT_OPS: + relative_fd =3D OPTS_GET(opts, cgroup.relative_fd, 0); + attr.link_create.cgroup.relative_fd =3D relative_fd; + attr.link_create.cgroup.expected_revision =3D + OPTS_GET(opts, cgroup.expected_revision, 0); + if (!OPTS_ZEROED(opts, cgroup)) + return libbpf_err(-EINVAL); + break; default: if (!OPTS_ZEROED(opts, flags)) return libbpf_err(-EINVAL); diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 0c8bf0b5cce4..70a00da54ff5 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -13462,12 +13462,19 @@ static int bpf_link__detach_struct_ops(struct bpf= _link *link) return close(link->fd); } =20 -struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map) +struct bpf_link *bpf_map__attach_struct_ops_opts(const struct bpf_map *map, + const struct bpf_struct_ops_opts *opts) { + DECLARE_LIBBPF_OPTS(bpf_link_create_opts, link_opts); struct bpf_link_struct_ops *link; __u32 zero =3D 0; int err, fd; =20 + if (!OPTS_VALID(opts, bpf_struct_ops_opts)) { + pr_warn("map '%s': invalid opts\n", map->name); + return libbpf_err_ptr(-EINVAL); + } + if (!bpf_map__is_struct_ops(map)) { pr_warn("map '%s': can't attach non-struct_ops map\n", map->name); return libbpf_err_ptr(-EINVAL); @@ -13503,7 +13510,9 @@ struct bpf_link *bpf_map__attach_struct_ops(const s= truct bpf_map *map) return &link->link; } =20 - fd =3D bpf_link_create(map->fd, 0, BPF_STRUCT_OPS, NULL); + link_opts.cgroup.relative_fd =3D OPTS_GET(opts, relative_fd, 0); + + fd =3D bpf_link_create(map->fd, 0, BPF_STRUCT_OPS, &link_opts); if (fd < 0) { free(link); return libbpf_err_ptr(fd); @@ -13515,6 +13524,11 @@ struct bpf_link *bpf_map__attach_struct_ops(const = struct bpf_map *map) return &link->link; } =20 +struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map) +{ + return bpf_map__attach_struct_ops_opts(map, NULL); +} + /* * Swap the back struct_ops of a link with a new struct_ops map. */ diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index dfc37a615578..5aef44bcfcc2 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -920,6 +920,20 @@ bpf_program__attach_cgroup_opts(const struct bpf_progr= am *prog, int cgroup_fd, struct bpf_map; =20 LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_ma= p *map); + +struct bpf_struct_ops_opts { + /* size of this struct, for forward/backward compatibility */ + size_t sz; + __u32 flags; + __u32 relative_fd; + __u64 expected_revision; + size_t :0; +}; +#define bpf_struct_ops_opts__last_field expected_revision + +LIBBPF_API struct bpf_link * +bpf_map__attach_struct_ops_opts(const struct bpf_map *map, + const struct bpf_struct_ops_opts *opts); LIBBPF_API int bpf_link__update_map(struct bpf_link *link, const struct bp= f_map *map); =20 struct bpf_iter_attach_opts { diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index d18fbcea7578..4779190c97b6 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -454,4 +454,5 @@ LIBBPF_1.7.0 { bpf_prog_assoc_struct_ops; bpf_program__assoc_struct_ops; btf__permute; + bpf_map__attach_struct_ops_opts; } LIBBPF_1.6.0; --=20 2.43.0