From patchwork Sun Dec 17 08:11:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kui-Feng Lee X-Patchwork-Id: 13495793 X-Patchwork-Delegate: bpf@iogearbox.net Received: from mail-qk1-f182.google.com (mail-qk1-f182.google.com [209.85.222.182]) (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 F23FE1FC2 for ; Sun, 17 Dec 2023 08:11:47 +0000 (UTC) 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="BTNT8z0/" Received: by mail-qk1-f182.google.com with SMTP id af79cd13be357-77f70206016so200406185a.0 for ; Sun, 17 Dec 2023 00:11:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1702800706; x=1703405506; 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=Lvmt8YREIApGjYxNLedkB7FdNs8C41Y06GXdrYdOM18=; b=BTNT8z0/8aWPZsqlBa1Wje0NYqmBXvjTNH5I7Tr1w9l/VNy1kr9oiMiaoriZ1W0vQl KJdW/AnrK2HRMTueXjLU6YY/VBbJBSo41p4U+vvM9TLFDLpnvd4nf5sowsm2Y7kh0wiS 2Igkf+BXSPojoN5b97YVjG81ZVL7ZdXJr85bUFhwi52w85oueQNB8n0JG7Q0W/RCe4ll wQk5vE3P/fjkoF8/yLjYK90CnUKTk54sFne1U4eypTILxPq48O+shUMzV/xnb+WTn9jV rJF+3Cue+axujjSu8j4BWV7Nh76cYoaNVYIPDCRNN0mSWYcP+vbSyq72lcuMzBAgP5M5 WjyA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702800706; x=1703405506; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Lvmt8YREIApGjYxNLedkB7FdNs8C41Y06GXdrYdOM18=; b=pI8lGhWvHfUX8A3poL8PIRkNBsYsgELTbN/ZynD9sjcA0t0fM1WQ/Zaub8MwIh3QZ0 afM9gZCt+Cr/d+eQSJ6Q9VU5fd3lvgEYrEcvc2jMC9Socmu0Z2CTKC2uyzIxNmI24hFi cvn+kHUMTLoJS0ADyCPDpVMUVKAQJphpyWBhllZS+QPRRQQib2IF+Ngx5OOb2o3zS8r+ Gs70erpLyxPlwW2Ie420rJ7LNdOH/+buA29otTtShQQ4JyIq8G6XDVuKt42EACkLEcYM aQyA+Vfp8zqgl+Qmpz9OmHL0fgn+AmDlMPDzM6pysnPqGSAmhLQ/SgD3tHFJGKP2Ndm6 vKxg== X-Gm-Message-State: AOJu0YzQTb+X89ii97fjURVkkCkNL0RE3nvZdVTJMXYRc5owPMcmWdN6 FBE5syI7yStP4fQ/J9FCJqPEze71KEs= X-Google-Smtp-Source: AGHT+IFVoodO0oFn0RBIuQVrYQBLLCN3LGCLYw4Rc4L1WWmeUDE+atstaQ6nH/+DrGAUJP74aM1Y9g== X-Received: by 2002:a05:620a:229:b0:77f:b905:312c with SMTP id u9-20020a05620a022900b0077fb905312cmr3566270qkm.137.1702800706536; Sun, 17 Dec 2023 00:11:46 -0800 (PST) Received: from kickker.attlocal.net ([2600:1700:6cf8:1240:bb8c:c0f2:4408:50cf]) by smtp.gmail.com with ESMTPSA id c85-20020a814e58000000b005e303826838sm3399415ywb.56.2023.12.17.00.11.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 17 Dec 2023 00:11:46 -0800 (PST) From: thinker.li@gmail.com To: bpf@vger.kernel.org, ast@kernel.org, martin.lau@linux.dev, song@kernel.org, kernel-team@meta.com, andrii@kernel.org, drosen@google.com Cc: sinquersw@gmail.com, kuifeng@meta.com, Kui-Feng Lee Subject: [PATCH bpf-next v14 04/14] bpf: add struct_ops_tab to btf. Date: Sun, 17 Dec 2023 00:11:21 -0800 Message-Id: <20231217081132.1025020-5-thinker.li@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231217081132.1025020-1-thinker.li@gmail.com> References: <20231217081132.1025020-1-thinker.li@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net From: Kui-Feng Lee Maintain a registry of registered struct_ops types in the per-btf (module) struct_ops_tab. This registry allows for easy lookup of struct_ops types that are registered by a specific module. It is a preparation work for supporting kernel module struct_ops in a latter patch. Each struct_ops will be registered under its own kernel module btf and will be stored in the newly added btf->struct_ops_tab. The bpf verifier and bpf syscall (e.g. prog and map cmd) can find the struct_ops and its btf type/size/id... information from btf->struct_ops_tab. Signed-off-by: Kui-Feng Lee --- include/linux/btf.h | 2 ++ kernel/bpf/btf.c | 62 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 64 insertions(+) diff --git a/include/linux/btf.h b/include/linux/btf.h index 1d852dad7473..a68604904f4e 100644 --- a/include/linux/btf.h +++ b/include/linux/btf.h @@ -584,4 +584,6 @@ static inline bool btf_type_is_struct_ptr(struct btf *btf, const struct btf_type return btf_type_is_struct(t); } +struct bpf_struct_ops_desc; + #endif diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 46bf3a6f4bb0..2ce2c3fd477e 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -241,6 +241,12 @@ struct btf_id_dtor_kfunc_tab { struct btf_id_dtor_kfunc dtors[]; }; +struct btf_struct_ops_tab { + u32 cnt; + u32 capacity; + struct bpf_struct_ops_desc ops[]; +}; + struct btf { void *data; struct btf_type **types; @@ -258,6 +264,7 @@ struct btf { struct btf_kfunc_set_tab *kfunc_set_tab; struct btf_id_dtor_kfunc_tab *dtor_kfunc_tab; struct btf_struct_metas *struct_meta_tab; + struct btf_struct_ops_tab *struct_ops_tab; /* split BTF support */ struct btf *base_btf; @@ -1688,11 +1695,20 @@ static void btf_free_struct_meta_tab(struct btf *btf) btf->struct_meta_tab = NULL; } +static void btf_free_struct_ops_tab(struct btf *btf) +{ + struct btf_struct_ops_tab *tab = btf->struct_ops_tab; + + kfree(tab); + btf->struct_ops_tab = NULL; +} + static void btf_free(struct btf *btf) { btf_free_struct_meta_tab(btf); btf_free_dtor_kfunc_tab(btf); btf_free_kfunc_set_tab(btf); + btf_free_struct_ops_tab(btf); kvfree(btf->types); kvfree(btf->resolved_sizes); kvfree(btf->resolved_ids); @@ -8597,3 +8613,49 @@ bool btf_type_ids_nocast_alias(struct bpf_verifier_log *log, return !strncmp(reg_name, arg_name, cmp_len); } + +static int +btf_add_struct_ops(struct btf *btf, struct bpf_struct_ops *st_ops) +{ + struct btf_struct_ops_tab *tab, *new_tab; + int i; + + if (!btf) + return -ENOENT; + + /* Assume this function is called for a module when the module is + * loading. + */ + + tab = btf->struct_ops_tab; + if (!tab) { + tab = kzalloc(offsetof(struct btf_struct_ops_tab, ops[4]), + GFP_KERNEL); + if (!tab) + return -ENOMEM; + tab->capacity = 4; + btf->struct_ops_tab = tab; + } + + for (i = 0; i < tab->cnt; i++) + if (tab->ops[i].st_ops == st_ops) + return -EEXIST; + + if (tab->cnt == tab->capacity) { + new_tab = krealloc(tab, + offsetof(struct btf_struct_ops_tab, + ops[tab->capacity * 2]), + GFP_KERNEL); + if (!new_tab) + return -ENOMEM; + tab = new_tab; + tab->capacity *= 2; + btf->struct_ops_tab = tab; + } + + tab->ops[btf->struct_ops_tab->cnt].st_ops = st_ops; + + btf->struct_ops_tab->cnt++; + + return 0; +}