From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-x649.google.com (mail-pl1-x649.google.com [IPv6:2607:f8b0:4864:20::649]) by mail.toke.dk (Postfix) with ESMTPS id 470519B2E0C for ; Fri, 4 Nov 2022 04:25:37 +0100 (CET) Authentication-Results: mail.toke.dk; dkim=pass (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20210112 header.b=F/j+r+DQ Received: by mail-pl1-x649.google.com with SMTP id c1-20020a170902d48100b0018723580343so2629993plg.15 for ; Thu, 03 Nov 2022 20:25:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=YbRm3I0sewWtsZIHwhErDFMz3x0ncMPhKVqkK3e/Kzk=; b=F/j+r+DQWgWU+H64J7k+Tlw9APbvQO6yhhwJkgncOiWnKlmmd7ff3U0fDMWcrIM6eA Rrc6+HsRPDXVFkN/1Ol4jOSGhYk5Cu9FHGQdp5u2VJzi/qceoBkwLigm8V1aSgsBQSyH t2yGCOTZY8ZguLjd7JLXNalfPBqujqIfzSAqmR9dudUMpphE2D4hoDFPrK6M3xMipjdv kqgjtByufledR5lP2KjsFzIIRNsUFCQbD0UXrW6ZohJ2eQLFOicozTT+r4+rEsHhQ2a5 PDPpXcDvhQeczI4vZMBENr+pBOUlgphRkuSIuEzsnnUi4HLZf13zUZMJMQtvH7HcspTF P9Ew== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=YbRm3I0sewWtsZIHwhErDFMz3x0ncMPhKVqkK3e/Kzk=; b=zGZoNCiEu4gJo5NWhANN9RG9Cc2M5dt6p0T3Fcul5EKHKkO+2jTfCqVmhFKzgLUyTR i0Yj/zmvffbISLafI1Jtfzz6mS9hUcvKWxz/J89lYW2JzjHDBrO30kUOHIP9BivARADG VdOCnLQf8zbWMzXsE5n579xyEFZA322u7YfNx3Nq2StfEkeMtQyLVOyo+OngMtdOU/4x Xljm4LiB+rmkx7Ekauy+bIys8CEmIDPzc2ot6KBF+A039Z51ANfJpjFEJvVZZf9oCsQG 1wemuyFoZp7vfRV6WBQnrrMv0CnDdOVV8R/f3nTt63CUmfWSVfSlkZ2MW2u2Axchxku1 yP7A== X-Gm-Message-State: ACrzQf2iFHlIfm6Sthlr65jnvpi/U1zVZY3SEH5THVzkt+efPZihpyL1 2G4GTZ9vM4Noe4zvLr1thXwIAPc= X-Google-Smtp-Source: AMsMyM7Z6bdvew+CNuqL+zRO4xlM9NhZdHxVH3wfWepJiyS61542z1snHXjcv2qO5a2qvaaQV4BBXL8= X-Received: from sdf.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5935]) (user=sdf job=sendgmr) by 2002:aa7:9421:0:b0:56b:b2a8:6822 with SMTP id y1-20020aa79421000000b0056bb2a86822mr33149365pfo.86.1667532335655; Thu, 03 Nov 2022 20:25:35 -0700 (PDT) Date: Thu, 3 Nov 2022 20:25:19 -0700 In-Reply-To: <20221104032532.1615099-1-sdf@google.com> Mime-Version: 1.0 References: <20221104032532.1615099-1-sdf@google.com> X-Mailer: git-send-email 2.38.1.431.g37b22c650d-goog Message-ID: <20221104032532.1615099-2-sdf@google.com> From: Stanislav Fomichev To: bpf@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Message-ID-Hash: BGIQQROPNTFMRHD47PTRGST5HNWW56ZN X-Message-ID-Hash: BGIQQROPNTFMRHD47PTRGST5HNWW56ZN X-MailFrom: 3L4ZkYwMKCe4iTVWeeWbU.SecnTf-XYdjinTf-fheZUSj.dUj@flex--sdf.bounces.google.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: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org, David Ahern , Jakub Kicinski , Willem de Bruijn , Jesper Dangaard Brouer , Anatoly Burakov , Alexander Lobakin , Magnus Karlsson , Maryam Tahhan , xdp-hints@xdp-project.net, netdev@vger.kernel.org X-Mailman-Version: 3.3.5 Precedence: list Subject: [xdp-hints] [RFC bpf-next v2 01/14] bpf: Introduce bpf_patch List-Id: XDP hardware hints design discussion Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: A simple abstraction around a series of instructions that transparently handles resizing. Currently, we have insn_buf[16] in convert_ctx_accesses which might not be enough for xdp kfuncs. If we find this abstraction helpful, we might convert existing insn_buf[16] to it in the future. Cc: John Fastabend Cc: David Ahern Cc: Martin KaFai Lau Cc: Jakub Kicinski Cc: Willem de Bruijn Cc: Jesper Dangaard Brouer Cc: Anatoly Burakov Cc: Alexander Lobakin Cc: Magnus Karlsson Cc: Maryam Tahhan Cc: xdp-hints@xdp-project.net Cc: netdev@vger.kernel.org Signed-off-by: Stanislav Fomichev --- include/linux/bpf_patch.h | 27 +++++++++++++++++++++ kernel/bpf/Makefile | 2 +- kernel/bpf/bpf_patch.c | 51 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 79 insertions(+), 1 deletion(-) create mode 100644 include/linux/bpf_patch.h create mode 100644 kernel/bpf/bpf_patch.c diff --git a/include/linux/bpf_patch.h b/include/linux/bpf_patch.h new file mode 100644 index 000000000000..81ff738eef8d --- /dev/null +++ b/include/linux/bpf_patch.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +#ifndef _LINUX_BPF_PATCH_H +#define _LINUX_BPF_PATCH_H 1 + +#include + +struct bpf_patch { + struct bpf_insn *insn; + size_t capacity; + size_t len; + int err; +}; + +void bpf_patch_free(struct bpf_patch *patch); +size_t bpf_patch_len(const struct bpf_patch *patch); +int bpf_patch_err(const struct bpf_patch *patch); +void __bpf_patch_append(struct bpf_patch *patch, struct bpf_insn insn); +struct bpf_insn *bpf_patch_data(const struct bpf_patch *patch); + +#define bpf_patch_append(patch, ...) ({ \ + struct bpf_insn insn[] = { __VA_ARGS__ }; \ + int i; \ + for (i = 0; i < ARRAY_SIZE(insn); i++) \ + __bpf_patch_append(patch, insn[i]); \ +}) + +#endif diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index 3a12e6b400a2..5724f36292a5 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -13,7 +13,7 @@ obj-$(CONFIG_BPF_SYSCALL) += bpf_local_storage.o bpf_task_storage.o obj-${CONFIG_BPF_LSM} += bpf_inode_storage.o obj-$(CONFIG_BPF_SYSCALL) += disasm.o obj-$(CONFIG_BPF_JIT) += trampoline.o -obj-$(CONFIG_BPF_SYSCALL) += btf.o memalloc.o +obj-$(CONFIG_BPF_SYSCALL) += btf.o memalloc.o bpf_patch.o obj-$(CONFIG_BPF_JIT) += dispatcher.o ifeq ($(CONFIG_NET),y) obj-$(CONFIG_BPF_SYSCALL) += devmap.o diff --git a/kernel/bpf/bpf_patch.c b/kernel/bpf/bpf_patch.c new file mode 100644 index 000000000000..82a10bf5624a --- /dev/null +++ b/kernel/bpf/bpf_patch.c @@ -0,0 +1,51 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include + +void bpf_patch_free(struct bpf_patch *patch) +{ + kfree(patch->insn); +} + +size_t bpf_patch_len(const struct bpf_patch *patch) +{ + return patch->len; +} + +int bpf_patch_err(const struct bpf_patch *patch) +{ + return patch->err; +} + +void __bpf_patch_append(struct bpf_patch *patch, struct bpf_insn insn) +{ + void *arr; + + if (patch->err) + return; + + if (patch->len + 1 > patch->capacity) { + if (!patch->capacity) + patch->capacity = 16; + else + patch->capacity *= 2; + + arr = krealloc_array(patch->insn, patch->capacity, sizeof(insn), GFP_KERNEL); + if (!arr) { + patch->err = -ENOMEM; + kfree(patch->insn); + return; + } + + patch->insn = arr; + patch->capacity *= 2; + } + + patch->insn[patch->len++] = insn; +} +EXPORT_SYMBOL(__bpf_patch_append); + +struct bpf_insn *bpf_patch_data(const struct bpf_patch *patch) +{ + return patch->insn; +} -- 2.38.1.431.g37b22c650d-goog