From a537d06c72853c054c57d75af4074c1749e47947 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Tue, 26 Oct 2021 20:41:22 +0200 Subject: [PATCH] bpf-headers: add a package with kernel headers for ebpf In order to genererate suitable kernel headers, a 5.10 kernel tree is prepared with a default config for mips. The arch is forced to mips in order to avoid issues with inline asm on various architectures in a way that doesn't involve relying on the host toolchain/headers. It also has the advantage of supporting both endian types Signed-off-by: Felix Fietkau --- include/bpf.mk | 65 ++++++++++++ package/kernel/bpf-headers/Makefile | 99 +++++++++++++++++++ .../src/include/generated/bounds.h | 14 +++ 3 files changed, 178 insertions(+) create mode 100644 include/bpf.mk create mode 100644 package/kernel/bpf-headers/Makefile create mode 100644 package/kernel/bpf-headers/src/include/generated/bounds.h diff --git a/include/bpf.mk b/include/bpf.mk new file mode 100644 index 0000000000..3dc65c7685 --- /dev/null +++ b/include/bpf.mk @@ -0,0 +1,65 @@ +ifneq ($(CONFIG_BPF_TOOLCHAIN_HOST),) + BPF_TOOLCHAIN_HOST_PATH:=$(call qstrip,$(CONFIG_BPF_TOOLCHAIN_HOST_PATH)) + ifneq ($(BPF_TOOLCHAIN_HOST_PATH),) + BPF_PATH:=$(BPF_TOOLCHAIN_HOST_PATH)/bin:$(PATH) + else + BPF_PATH:=$(BPF_PATH) + endif + CLANG:=$(firstword $(shell PATH='$(BPF_PATH)' which clang clang-13 clang-12 clang-11)) + LLVM_VER:=$(subst clang,,$(notdir $(CLANG))) +else + CLANG:=$(STAGING_DIR_HOST)/bin/clang + LLVM_VER:= +endif + +LLVM_PATH:=$(dir $(CLANG)) +LLVM_LLC:=$(LLVM_PATH)/llc$(LLVM_VER) +LLVM_DIS:=$(LLVM_PATH)/llvm-dis$(LLVM_VER) +LLVM_OPT:=$(LLVM_PATH)/opt$(LLVM_VER) +LLVM_STRIP:=$(LLVM_PATH)/llvm-strip$(LLVM_VER) + +BPF_KARCH:=mips +BPF_ARCH:=mips$(if $(CONFIG_BIG_ENDIAN),,el) + +BPF_HEADERS_DIR:=$(STAGING_DIR)/bpf-headers + +BPF_KERNEL_INCLUDE := \ + -nostdinc -isystem $(TOOLCHAIN_DIR)/include \ + -I$(BPF_HEADERS_DIR)/arch/$(BPF_KARCH)/include \ + -I$(BPF_HEADERS_DIR)/arch/$(BPF_KARCH)/include/asm/mach-generic \ + -I$(BPF_HEADERS_DIR)/arch/$(BPF_KARCH)/include/generated \ + -I$(BPF_HEADERS_DIR)/include \ + -I$(BPF_HEADERS_DIR)/arch/$(BPF_KARCH)/include/uapi \ + -I$(BPF_HEADERS_DIR)/arch/$(BPF_KARCH)/include/generated/uapi \ + -I$(BPF_HEADERS_DIR)/include/uapi \ + -I$(BPF_HEADERS_DIR)/include/generated/uapi \ + -I$(BPF_HEADERS_DIR)/tools/lib \ + -I$(BPF_HEADERS_DIR)/tools/testing/selftests \ + -I$(BPF_HEADERS_DIR)/samples/bpf \ + -include linux/kconfig.h -include asm_goto_workaround.h + +BPF_CFLAGS := \ + $(BPF_KERNEL_INCLUDE) -I$(PKG_BUILD_DIR) \ + -D__KERNEL__ -D__BPF_TRACING__ \ + -D__TARGET_ARCH_${BPF_KARCH} \ + -m$(if $(CONFIG_BIG_ENDIAN),big,little)-endian \ + -fno-stack-protector -Wall \ + -Wno-unused-value -Wno-pointer-sign \ + -Wno-compare-distinct-pointer-types \ + -Wno-gnu-variable-sized-type-not-at-end \ + -Wno-address-of-packed-member -Wno-tautological-compare \ + -Wno-unknown-warning-option \ + -fno-asynchronous-unwind-tables \ + -Wno-uninitialized -Wno-unused-variable \ + -Wno-unused-label \ + -O2 -emit-llvm -Xclang -disable-llvm-passes + +define CompileBPF + $(CLANG) -g -target $(BPF_ARCH)-linux-gnu $(BPF_CFLAGS) $(2) \ + -c $(1) -o $(patsubst %.c,%.bc,$(1)) + $(LLVM_OPT) -O2 -mtriple=bpf-pc-linux < $(patsubst %.c,%.bc,$(1)) > $(patsubst %.c,%.opt,$(1)) + $(LLVM_DIS) < $(patsubst %.c,%.opt,$(1)) > $(patsubst %.c,%.S,$(1)) + $(LLVM_LLC) -march=bpf -filetype=obj -o $(patsubst %.c,%.o,$(1)) < $(patsubst %.c,%.S,$(1)) + $(LLVM_STRIP) --strip-debug $(patsubst %.c,%.o,$(1)) +endef + diff --git a/package/kernel/bpf-headers/Makefile b/package/kernel/bpf-headers/Makefile new file mode 100644 index 0000000000..5f5b89370d --- /dev/null +++ b/package/kernel/bpf-headers/Makefile @@ -0,0 +1,99 @@ +# +# Copyright (C) 2006-2009 OpenWrt.org +# +# This is free software, licensed under the GNU General Public License v2. +# See /LICENSE for more information. +# +include $(TOPDIR)/rules.mk + +override QUILT:= +override HOST_QUILT:= + +include $(INCLUDE_DIR)/kernel.mk + + +PKG_NAME:=linux +PKG_PATCHVER:=5.10 +PKG_VERSION:=$(PKG_PATCHVER)$(strip $(LINUX_VERSION-$(PKG_PATCHVER))) +PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.xz +PKG_SOURCE_URL:=$(LINUX_SITE) +PKG_HASH:=$(LINUX_KERNEL_HASH-$(strip $(PKG_VERSION))) +PKG_BUILD_DIR:=$(KERNEL_BUILD_DIR)/bpf-headers/$(PKG_NAME)-$(PKG_VERSION) + +GENERIC_BACKPORT_DIR := $(GENERIC_PLATFORM_DIR)/backport$(if $(wildcard $(GENERIC_PLATFORM_DIR)/backport-$(PKG_PATCHVER)),-$(PKG_PATCHVER)) +GENERIC_PATCH_DIR := $(GENERIC_PLATFORM_DIR)/pending$(if $(wildcard $(GENERIC_PLATFORM_DIR)/pending-$(PKG_PATCHVER)),-$(PKG_PATCHVER)) +GENERIC_HACK_DIR := $(GENERIC_PLATFORM_DIR)/hack$(if $(wildcard $(GENERIC_PLATFORM_DIR)/hack-$(PKG_PATCHVER)),-$(PKG_PATCHVER)) +GENERIC_FILES_DIR := $(foreach dir,$(wildcard $(GENERIC_PLATFORM_DIR)/files $(GENERIC_PLATFORM_DIR)/files-$(PKG_PATCHVER)),"$(dir)") +PATCH_DIR := $(CURDIR)/patches +FILES_DIR := + +REAL_LINUX_DIR := $(LINUX_DIR) +LINUX_DIR := $(PKG_BUILD_DIR) + +include $(INCLUDE_DIR)/bpf.mk +include $(INCLUDE_DIR)/package.mk + +define Package/bpf-headers + SECTION:=kernel + CATEGORY:=Kernel + TITLE:=eBPF kernel headers + BUILDONLY:=1 + HIDDEN:=1 +endef + +export HOST_EXTRACFLAGS=-I$(STAGING_DIR_HOST)/include + +KERNEL_MAKE := \ + $(MAKE) -C $(PKG_BUILD_DIR) \ + ARCH=$(BPF_KARCH) \ + CROSS_COMPILE=$(BPF_ARCH)-linux- \ + LLVM=1 CC="$(CLANG)" LD="$(TARGET_CROSS)ld" \ + HOSTCC="$(HOSTCC)" \ + HOSTCXX="$(HOSTCXX)" \ + HOST_LOADLIBES="-L$(STAGING_DIR_HOST)/lib" \ + KBUILD_HOSTLDLIBS="-L$(STAGING_DIR_HOST)/lib" \ + CONFIG_SHELL="$(BASH)" \ + INSTALL_HDR_PATH="$(PKG_BUILD_DIR)/user_headers" + +define Build/Patch + $(Kernel/Patch/Default) +endef + +BPF_DOC = $(PKG_BUILD_DIR)/scripts/bpf_helpers_doc.py + +define Build/Configure + grep -vE 'CONFIG_(CPU_.*ENDIAN|HZ)' $(PKG_BUILD_DIR)/arch/mips/configs/generic_defconfig > $(PKG_BUILD_DIR)/.config + echo 'CONFIG_CPU_$(if $(CONFIG_BIG_ENDIAN),BIG,LITTLE)_ENDIAN=y' >> $(PKG_BUILD_DIR)/.config + grep CONFIG_HZ $(REAL_LINUX_DIR)/.config >> $(PKG_BUILD_DIR)/.config + yes '' | $(KERNEL_MAKE) oldconfig + grep 'CONFIG_HZ=' $(REAL_LINUX_DIR)/.config | \ + cut -d= -f2 | \ + bc -q $(LINUX_DIR)/kernel/time/timeconst.bc \ + > $(LINUX_DIR)/include/generated/timeconst.h + $(BPF_DOC) --header \ + --file $(LINUX_DIR)/tools/include/uapi/linux/bpf.h \ + > $(PKG_BUILD_DIR)/tools/lib/bpf/bpf_helper_defs.h +endef + +define Build/Compile + $(KERNEL_MAKE) archprepare headers_install +endef + +define Build/InstallDev + mkdir -p $(1)/bpf-headers/arch $(1)/bpf-headers/tools + $(CP) \ + $(PKG_BUILD_DIR)/arch/$(BPF_KARCH) \ + $(1)/bpf-headers/arch/ + $(CP) \ + $(PKG_BUILD_DIR)/tools/lib \ + $(PKG_BUILD_DIR)/tools/testing \ + $(1)/bpf-headers/tools/ + $(CP) \ + $(PKG_BUILD_DIR)/include \ + $(PKG_BUILD_DIR)/samples \ + $(PKG_BUILD_DIR)/scripts \ + $(PKG_BUILD_DIR)/user_headers \ + $(1)/bpf-headers +endef + +$(eval $(call BuildPackage,bpf-headers)) diff --git a/package/kernel/bpf-headers/src/include/generated/bounds.h b/package/kernel/bpf-headers/src/include/generated/bounds.h new file mode 100644 index 0000000000..82ff01043c --- /dev/null +++ b/package/kernel/bpf-headers/src/include/generated/bounds.h @@ -0,0 +1,14 @@ +#ifndef __LINUX_BOUNDS_H__ +#define __LINUX_BOUNDS_H__ +/* + * DO NOT MODIFY. + * + * This file was generated by Kbuild + */ + +#define NR_PAGEFLAGS 23 /* __NR_PAGEFLAGS */ +#define MAX_NR_ZONES 4 /* __MAX_NR_ZONES */ +#define NR_CPUS_BITS 1 /* ilog2(CONFIG_NR_CPUS) */ +#define SPINLOCK_SIZE 64 /* sizeof(spinlock_t) */ + +#endif -- 2.30.2