From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo1-f41.google.com (mail-oo1-f41.google.com [209.85.161.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7EE3C38E5C5 for ; Tue, 23 Jun 2026 17:50:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.161.41 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782237015; cv=none; b=K2Yho4+90rkg5WUCCNNiY/HvMXVxTF0BGqIDqIopp4auv6X6aDoAQa5H9n+zOrGTALSNQC3OajBLxHKDtXLbWrIN9j6Ph8UB02xmK2SFkzmRbP5Cun8otpu/aw/S8qabVE8kflKrOpZLZwiQNvBlb3kXrNN6X6HK3k3lMLnHWg8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782237015; c=relaxed/simple; bh=gmLEo8Qxva12wQh7T7WKvyYkCRo+UtZhxyO4uYoxDck=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JSxPTAydbW8XRZyfUCac2LkOrwL+hbs9Ok8/nMGG9sjYGGshwC0GtnwRtWEztEEq+CaAxFgY4m7b/2aZfUHASyNamI0gPsT77zQcf4xDy1D3U1FXtGx1j/28usnHTlQD4KswGkAqjVaXzhAMnm21l4q4tdtrkFI4joJnlDYzHI0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=f23z+ISI; arc=none smtp.client-ip=209.85.161.41 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="f23z+ISI" Received: by mail-oo1-f41.google.com with SMTP id 006d021491bc7-6a11f19fcf6so88447eaf.3 for ; Tue, 23 Jun 2026 10:50:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1782237012; x=1782841812; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=TDpmIhKnKapld7EYbwQsM9K3Ane5eLzTjrBFUjiMOE8=; b=f23z+ISIBPgzqr7YlgKvwRRKA1HhvxzYQ04M4zFA95nNSB+PiTobo22qeCujsYaZq2 EFpx82BWwjvvtQUD/DnqpoK2/dvmzvJhVUEantSsLHW+Tcgw3zWmlzhgzg0Bio6cI8BQ lnF7FHtCtqkcbUiXAnIbwP7GuY4o2Q1PXVwanxZFalKgWr/cTrfzOd7/oYLqc04jAhLw DRQoyszSNEGVyhmlF4hgcc16xNDzC13r+wbwmbTW1YbDTSNevNs7Q08V9F3csSeUjiJD VOlvNAl50jGw0ALqubK2y1Is7a3rc5ZM0K6TvojU3XfgoCxKGQOedFtoCfMkr5UM4X4j mJHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782237012; x=1782841812; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=TDpmIhKnKapld7EYbwQsM9K3Ane5eLzTjrBFUjiMOE8=; b=pXGmltbePFlE1XOmkyfPO8Qb1OLyyvT8++2RC1GodAZ423zsp2HQWvWrHL55JmxqLm VxdBOoZoGXMeY0wPXfMuUSvM4WRAQevApHj8OkwKFAhV63Q7ivQYf3t+9L/ANZikokZE i5AgxJ341OvDt78iXrUZ9gcDlzH4p9HRiBhoUefObCQ799bQ4AH+ZD9Y0Z9x1Z8JqsTo 088CqmmEocvaIUwDdwYwKKXEahAVWfFQrcN4bb2t4UV2cdheMhmfMCR/XWS+tHOkOkZo 48RJzu51iKIbqiwIt0RW62YjCuSr/4HnF/1EEy4POoN7I21IiT/R8UqC3NhO6BnOcjAS GC2A== X-Gm-Message-State: AOJu0YwY6fDDgK3kgdVVsz3Fh8TsMxibLvaI6wVWKX9hVQmkcDirE7eN F4rAfHdZuCpkH5Hl6O3/oiCPDu3gBktXh0dzXKtPhlASUSCrzqiYazo1 X-Gm-Gg: AfdE7cm5753M2KGAfHHYAGRgisdklFV9NYHb6ajqjM4XFKlolwNa6bZidqvJ2zwNcsB c0+EdJ+L0hHYKXumPoexl9lZ/z2kFymcVtc6uf8+5sq2B/3o6+JykeW1wamG0XOxMrdFRmcgB99 l5W4WEq95GZWZw7V7M7ie2m++RgpjPODdqj4O0m0aQ7mX8BChY8NkXL2rU0N9B0WS5SVzzLj2vr WsFU0iLVBkX+HXuJIxUHrDw3nnqhM5QB9zKEAAQEuWCsrDl7TsXglRXw1IA/piAByDmUXk8p7lm uhYqbtMK/zJYOt7mmtSwn5dN2NeWRvC40WHz8iaZJCtUndpIVrbAmmclPKwS3xVMJuqpT8fQ7Dx e8K5WcqdMq2Iefqg9IJ9KsJoGO5cKwGa55M4lwStfRQKksiKG+urRt7T7AiJftN247b2TBCdkO6 ygIok= X-Received: by 2002:a05:6820:c453:10b0:6a1:19ad:7a0e with SMTP id 006d021491bc7-6a119ad7b61mr1256261eaf.17.1782237012515; Tue, 23 Jun 2026 10:50:12 -0700 (PDT) Received: from localhost ([2a03:2880:ff:73::]) by smtp.gmail.com with ESMTPSA id 006d021491bc7-6a0e9f2a4e9sm7350572eaf.2.2026.06.23.10.50.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Jun 2026 10:50:12 -0700 (PDT) From: Amery Hung To: bpf@vger.kernel.org Cc: netdev@vger.kernel.org, alexei.starovoitov@gmail.com, andrii@kernel.org, daniel@iogearbox.net, eddyz87@gmail.com, memxor@gmail.com, martin.lau@kernel.org, shakeel.butt@linux.dev, roman.gushchin@linux.dev, kuniyu@google.com, kerneljasonxing@gmail.com, ameryhung@gmail.com, kernel-team@meta.com Subject: [PATCH bpf-next v2 03/15] bpf: Add bpf_struct_ops accessor helpers Date: Tue, 23 Jun 2026 10:49:51 -0700 Message-ID: <20260623175006.3136053-4-ameryhung@gmail.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260623175006.3136053-1-ameryhung@gmail.com> References: <20260623175006.3136053-1-ameryhung@gmail.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Martin KaFai Lau Add the helper functions bpf_struct_ops_map_kdata(), bpf_struct_ops_kdata_map_id(), and bpf_struct_ops_map_cfi_stubs() in bpf_struct_ops.c. They will be called from cgroup.c in the upcoming patch to create a struct_ops to cgroup attachment link. bpf_struct_ops_valid_to_reg() is also exposed for the upcoming caller in cgroup.c. The link update validation is also refactored into a new function bpf_struct_ops_link_update_check() such that it can be reused by the caller in cgroup.c in the upcoming patch. Signed-off-by: Martin KaFai Lau Signed-off-by: Amery Hung --- include/linux/bpf.h | 28 +++++++++++++++++ kernel/bpf/bpf_struct_ops.c | 63 ++++++++++++++++++++++++++++--------- 2 files changed, 77 insertions(+), 14 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 7ac8873839f4..047ffc029666 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -2252,6 +2252,12 @@ u32 bpf_struct_ops_id(const void *kdata); int bpf_struct_ops_for_each_prog(const void *kdata, int (*cb)(struct bpf_prog *prog, void *data), void *data); +void *bpf_struct_ops_map_kdata(struct bpf_map *map); +u32 bpf_struct_ops_kdata_map_id(void *kdata); +void *bpf_struct_ops_map_cfi_stubs(struct bpf_map *map); +bool bpf_struct_ops_valid_to_reg(struct bpf_map *map); +int bpf_struct_ops_link_update_check(struct bpf_map *new_map, struct bpf_map *old_map, + struct bpf_map *expected_old_map); #ifdef CONFIG_NET /* Define it here to avoid the use of forward declaration */ @@ -2316,6 +2322,28 @@ static inline void bpf_map_struct_ops_info_fill(struct bpf_map_info *info, struc static inline void bpf_struct_ops_desc_release(struct bpf_struct_ops_desc *st_ops_desc) { } +static inline void *bpf_struct_ops_map_kdata(struct bpf_map *map) +{ + return NULL; +} +static inline u32 bpf_struct_ops_kdata_map_id(void *kdata) +{ + return 0; +} +static inline void *bpf_struct_ops_map_cfi_stubs(struct bpf_map *map) +{ + return NULL; +} +static inline bool bpf_struct_ops_valid_to_reg(struct bpf_map *map) +{ + return false; +} +static inline int bpf_struct_ops_link_update_check(struct bpf_map *new_map, + struct bpf_map *old_map, + struct bpf_map *expected_old_map) +{ + return -EOPNOTSUPP; +} #endif diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c index c422ce41873e..1ca44584ed17 100644 --- a/kernel/bpf/bpf_struct_ops.c +++ b/kernel/bpf/bpf_struct_ops.c @@ -1236,7 +1236,33 @@ int bpf_struct_ops_for_each_prog(const void *kdata, } EXPORT_SYMBOL_GPL(bpf_struct_ops_for_each_prog); -static bool bpf_struct_ops_valid_to_reg(struct bpf_map *map) +void *bpf_struct_ops_map_kdata(struct bpf_map *map) +{ + struct bpf_struct_ops_map *st_map; + + st_map = container_of(map, struct bpf_struct_ops_map, map); + return st_map->kvalue.data; +} + +u32 bpf_struct_ops_kdata_map_id(void *kdata) +{ + struct bpf_struct_ops_value *kvalue = + container_of(kdata, struct bpf_struct_ops_value, data); + struct bpf_struct_ops_map *st_map = + container_of(kvalue, struct bpf_struct_ops_map, kvalue); + + return st_map->map.id; +} + +void *bpf_struct_ops_map_cfi_stubs(struct bpf_map *map) +{ + struct bpf_struct_ops_map *st_map; + + st_map = container_of(map, struct bpf_struct_ops_map, map); + return st_map->st_ops_desc->st_ops->cfi_stubs; +} + +bool bpf_struct_ops_valid_to_reg(struct bpf_map *map) { struct bpf_struct_ops_map *st_map = (struct bpf_struct_ops_map *)map; @@ -1289,6 +1315,26 @@ static int bpf_struct_ops_map_link_fill_link_info(const struct bpf_link *link, return 0; } +int bpf_struct_ops_link_update_check(struct bpf_map *new_map, + struct bpf_map *old_map, + struct bpf_map *expected_old_map) +{ + struct bpf_struct_ops_map *st_map, *old_st_map; + + if (!old_map) + return -ENOLINK; + if (expected_old_map && old_map != expected_old_map) + return -EPERM; + + st_map = container_of(new_map, struct bpf_struct_ops_map, map); + old_st_map = container_of(old_map, struct bpf_struct_ops_map, map); + /* The new and old struct_ops must be the same type. */ + if (st_map->st_ops_desc != old_st_map->st_ops_desc) + return -EINVAL; + + return 0; +} + static int bpf_struct_ops_map_link_update(struct bpf_link *link, struct bpf_map *new_map, struct bpf_map *expected_old_map) { @@ -1307,23 +1353,12 @@ static int bpf_struct_ops_map_link_update(struct bpf_link *link, struct bpf_map return -EOPNOTSUPP; mutex_lock(&update_mutex); - old_map = st_link->map; - if (!old_map) { - err = -ENOLINK; - goto err_out; - } - if (expected_old_map && old_map != expected_old_map) { - err = -EPERM; + err = bpf_struct_ops_link_update_check(new_map, old_map, expected_old_map); + if (err) goto err_out; - } old_st_map = container_of(old_map, struct bpf_struct_ops_map, map); - /* The new and old struct_ops must be the same type. */ - if (st_map->st_ops_desc != old_st_map->st_ops_desc) { - err = -EINVAL; - goto err_out; - } err = st_map->st_ops_desc->st_ops->update(st_map->kvalue.data, old_st_map->kvalue.data, link); if (err) -- 2.53.0-Meta