1# SPDX-License-Identifier: GPL-2.0 2 3HID_SAMPLES_PATH ?= $(abspath $(srctree)/$(src)) 4TOOLS_PATH := $(HID_SAMPLES_PATH)/../../tools 5 6pound := \# 7 8# List of programs to build 9tprogs-y += hid_mouse 10 11# Libbpf dependencies 12LIBBPF_SRC = $(TOOLS_PATH)/lib/bpf 13LIBBPF_OUTPUT = $(abspath $(HID_SAMPLES_PATH))/libbpf 14LIBBPF_DESTDIR = $(LIBBPF_OUTPUT) 15LIBBPF_INCLUDE = $(LIBBPF_DESTDIR)/include 16LIBBPF = $(LIBBPF_OUTPUT)/libbpf.a 17 18EXTRA_HEADERS := hid_bpf_attach.h 19EXTRA_BPF_HEADERS := hid_bpf_helpers.h 20 21hid_mouse-objs := hid_mouse.o 22 23# Tell kbuild to always build the programs 24always-y := $(tprogs-y) 25 26ifeq ($(ARCH), arm) 27# Strip all except -D__LINUX_ARM_ARCH__ option needed to handle linux 28# headers when arm instruction set identification is requested. 29ARM_ARCH_SELECTOR := $(filter -D__LINUX_ARM_ARCH__%, $(KBUILD_CFLAGS)) 30BPF_EXTRA_CFLAGS := $(ARM_ARCH_SELECTOR) 31TPROGS_CFLAGS += $(ARM_ARCH_SELECTOR) 32endif 33 34ifeq ($(ARCH), mips) 35TPROGS_CFLAGS += -D__SANE_USERSPACE_TYPES__ 36ifdef CONFIG_MACH_LOONGSON64 37BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-loongson64 38BPF_EXTRA_CFLAGS += -I$(srctree)/arch/mips/include/asm/mach-generic 39endif 40endif 41 42TPROGS_CFLAGS += -Wall -O2 43TPROGS_CFLAGS += -Wmissing-prototypes 44TPROGS_CFLAGS += -Wstrict-prototypes 45 46TPROGS_CFLAGS += -I$(objtree)/usr/include 47TPROGS_CFLAGS += -I$(LIBBPF_INCLUDE) 48TPROGS_CFLAGS += -I$(srctree)/tools/include 49 50ifdef SYSROOT 51TPROGS_CFLAGS += --sysroot=$(SYSROOT) 52TPROGS_LDFLAGS := -L$(SYSROOT)/usr/lib 53endif 54 55TPROGS_LDLIBS += $(LIBBPF) -lelf -lz 56 57# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline: 58# make M=samples/bpf LLC=~/git/llvm-project/llvm/build/bin/llc CLANG=~/git/llvm-project/llvm/build/bin/clang 59LLC ?= llc 60CLANG ?= clang 61OPT ?= opt 62LLVM_DIS ?= llvm-dis 63LLVM_OBJCOPY ?= llvm-objcopy 64LLVM_READELF ?= llvm-readelf 65BTF_PAHOLE ?= pahole 66 67# Detect that we're cross compiling and use the cross compiler 68ifdef CROSS_COMPILE 69CLANG_ARCH_ARGS = --target=$(notdir $(CROSS_COMPILE:%-=%)) 70endif 71 72# Don't evaluate probes and warnings if we need to run make recursively 73ifneq ($(src),) 74HDR_PROBE := $(shell printf "$(pound)include <linux/types.h>\n struct list_head { int a; }; int main() { return 0; }" | \ 75 $(CC) $(TPROGS_CFLAGS) $(TPROGS_LDFLAGS) -x c - \ 76 -o /dev/null 2>/dev/null && echo okay) 77 78ifeq ($(HDR_PROBE),) 79$(warning WARNING: Detected possible issues with include path.) 80$(warning WARNING: Please install kernel headers locally (make headers_install).) 81endif 82 83BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help 2>&1 | grep dwarfris) 84BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help 2>&1 | grep BTF) 85BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --help 2>&1 | grep -i 'usage.*llvm') 86BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" | \ 87 $(CLANG) -target bpf -O2 -g -c -x c - -o ./llvm_btf_verify.o; \ 88 $(LLVM_READELF) -S ./llvm_btf_verify.o | grep BTF; \ 89 /bin/rm -f ./llvm_btf_verify.o) 90 91BPF_EXTRA_CFLAGS += -fno-stack-protector 92ifneq ($(BTF_LLVM_PROBE),) 93 BPF_EXTRA_CFLAGS += -g 94else 95ifneq ($(and $(BTF_LLC_PROBE),$(BTF_PAHOLE_PROBE),$(BTF_OBJCOPY_PROBE)),) 96 BPF_EXTRA_CFLAGS += -g 97 LLC_FLAGS += -mattr=dwarfris 98 DWARF2BTF = y 99endif 100endif 101endif 102 103# Trick to allow make to be run from this directory 104all: 105 $(MAKE) -C ../../ M=$(CURDIR) HID_SAMPLES_PATH=$(CURDIR) 106 107clean: 108 $(MAKE) -C ../../ M=$(CURDIR) clean 109 @find $(CURDIR) -type f -name '*~' -delete 110 @$(RM) -r $(CURDIR)/libbpf $(CURDIR)/bpftool 111 112$(LIBBPF): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUTPUT) 113# Fix up variables inherited from Kbuild that tools/ build system won't like 114 $(MAKE) -C $(LIBBPF_SRC) RM='rm -rf' EXTRA_CFLAGS="$(TPROGS_CFLAGS)" \ 115 LDFLAGS=$(TPROGS_LDFLAGS) srctree=$(HID_SAMPLES_PATH)/../../ \ 116 O= OUTPUT=$(LIBBPF_OUTPUT)/ DESTDIR=$(LIBBPF_DESTDIR) prefix= \ 117 $@ install_headers 118 119BPFTOOLDIR := $(TOOLS_PATH)/bpf/bpftool 120BPFTOOL_OUTPUT := $(abspath $(HID_SAMPLES_PATH))/bpftool 121BPFTOOL := $(BPFTOOL_OUTPUT)/bootstrap/bpftool 122$(BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile) | $(BPFTOOL_OUTPUT) 123 $(MAKE) -C $(BPFTOOLDIR) srctree=$(HID_SAMPLES_PATH)/../../ \ 124 OUTPUT=$(BPFTOOL_OUTPUT)/ bootstrap 125 126$(LIBBPF_OUTPUT) $(BPFTOOL_OUTPUT): 127 $(call msg,MKDIR,$@) 128 $(Q)mkdir -p $@ 129 130FORCE: 131 132 133# Verify LLVM compiler tools are available and bpf target is supported by llc 134.PHONY: verify_cmds verify_target_bpf $(CLANG) $(LLC) 135 136verify_cmds: $(CLANG) $(LLC) 137 @for TOOL in $^ ; do \ 138 if ! (which -- "$${TOOL}" > /dev/null 2>&1); then \ 139 echo "*** ERROR: Cannot find LLVM tool $${TOOL}" ;\ 140 exit 1; \ 141 else true; fi; \ 142 done 143 144verify_target_bpf: verify_cmds 145 @if ! (${LLC} -march=bpf -mattr=help > /dev/null 2>&1); then \ 146 echo "*** ERROR: LLVM (${LLC}) does not support 'bpf' target" ;\ 147 echo " NOTICE: LLVM version >= 3.7.1 required" ;\ 148 exit 2; \ 149 else true; fi 150 151$(HID_SAMPLES_PATH)/*.c: verify_target_bpf $(LIBBPF) 152$(src)/*.c: verify_target_bpf $(LIBBPF) 153 154libbpf_hdrs: $(LIBBPF) 155 156.PHONY: libbpf_hdrs 157 158$(obj)/hid_mouse.o: $(obj)/hid_mouse.skel.h 159 160-include $(HID_SAMPLES_PATH)/Makefile.target 161 162VMLINUX_BTF_PATHS ?= $(abspath $(if $(O),$(O)/vmlinux)) \ 163 $(abspath $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux)) \ 164 $(abspath ./vmlinux) 165VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS)))) 166 167$(obj)/vmlinux.h: $(VMLINUX_BTF) $(BPFTOOL) 168ifeq ($(VMLINUX_H),) 169ifeq ($(VMLINUX_BTF),) 170 $(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)",\ 171 build the kernel or set VMLINUX_BTF or VMLINUX_H variable) 172endif 173 $(Q)$(BPFTOOL) btf dump file $(VMLINUX_BTF) format c > $@ 174else 175 $(Q)cp "$(VMLINUX_H)" $@ 176endif 177 178clean-files += vmlinux.h 179 180# Get Clang's default includes on this system, as opposed to those seen by 181# '-target bpf'. This fixes "missing" files on some architectures/distros, 182# such as asm/byteorder.h, asm/socket.h, asm/sockios.h, sys/cdefs.h etc. 183# 184# Use '-idirafter': Don't interfere with include mechanics except where the 185# build would have failed anyways. 186define get_sys_includes 187$(shell $(1) -v -E - </dev/null 2>&1 \ 188 | sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }') \ 189$(shell $(1) -dM -E - </dev/null | grep '#define __riscv_xlen ' | sed 's/#define /-D/' | sed 's/ /=/') 190endef 191 192CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG)) 193 194EXTRA_BPF_HEADERS_SRC := $(addprefix $(src)/,$(EXTRA_BPF_HEADERS)) 195 196$(obj)/%.bpf.o: $(src)/%.bpf.c $(EXTRA_BPF_HEADERS_SRC) $(obj)/vmlinux.h 197 @echo " CLANG-BPF " $@ 198 $(Q)$(CLANG) -g -O2 -target bpf -D__TARGET_ARCH_$(SRCARCH) \ 199 -Wno-compare-distinct-pointer-types -I$(srctree)/include \ 200 -I$(srctree)/samples/bpf -I$(srctree)/tools/include \ 201 -I$(LIBBPF_INCLUDE) $(CLANG_SYS_INCLUDES) \ 202 -c $(filter %.bpf.c,$^) -o $@ 203 204LINKED_SKELS := hid_mouse.skel.h 205clean-files += $(LINKED_SKELS) 206 207hid_mouse.skel.h-deps := hid_mouse.bpf.o hid_bpf_attach.bpf.o 208 209LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.bpf.c,$(foreach skel,$(LINKED_SKELS),$($(skel)-deps))) 210 211BPF_SRCS_LINKED := $(notdir $(wildcard $(src)/*.bpf.c)) 212BPF_OBJS_LINKED := $(patsubst %.bpf.c,$(obj)/%.bpf.o, $(BPF_SRCS_LINKED)) 213BPF_SKELS_LINKED := $(addprefix $(obj)/,$(LINKED_SKELS)) 214 215$(BPF_SKELS_LINKED): $(BPF_OBJS_LINKED) $(BPFTOOL) 216 @echo " BPF GEN-OBJ " $(@:.skel.h=) 217 $(Q)$(BPFTOOL) gen object $(@:.skel.h=.lbpf.o) $(addprefix $(obj)/,$($(@F)-deps)) 218 @echo " BPF GEN-SKEL" $(@:.skel.h=) 219 $(Q)$(BPFTOOL) gen skeleton $(@:.skel.h=.lbpf.o) name $(notdir $(@:.skel.h=)) > $@ 220 221# asm/sysreg.h - inline assembly used by it is incompatible with llvm. 222# But, there is no easy way to fix it, so just exclude it since it is 223# useless for BPF samples. 224# below we use long chain of commands, clang | opt | llvm-dis | llc, 225# to generate final object file. 'clang' compiles the source into IR 226# with native target, e.g., x64, arm64, etc. 'opt' does bpf CORE IR builtin 227# processing (llvm12) and IR optimizations. 'llvm-dis' converts 228# 'opt' output to IR, and finally 'llc' generates bpf byte code. 229$(obj)/%.o: $(src)/%.c 230 @echo " CLANG-bpf " $@ 231 $(Q)$(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(BPF_EXTRA_CFLAGS) \ 232 -I$(obj) -I$(srctree)/tools/testing/selftests/bpf/ \ 233 -I$(LIBBPF_INCLUDE) \ 234 -D__KERNEL__ -D__BPF_TRACING__ -Wno-unused-value -Wno-pointer-sign \ 235 -D__TARGET_ARCH_$(SRCARCH) -Wno-compare-distinct-pointer-types \ 236 -Wno-gnu-variable-sized-type-not-at-end \ 237 -Wno-address-of-packed-member -Wno-tautological-compare \ 238 -Wno-unknown-warning-option $(CLANG_ARCH_ARGS) \ 239 -fno-asynchronous-unwind-tables \ 240 -I$(srctree)/samples/hid/ \ 241 -O2 -emit-llvm -Xclang -disable-llvm-passes -c $< -o - | \ 242 $(OPT) -O2 -mtriple=bpf-pc-linux | $(LLVM_DIS) | \ 243 $(LLC) -march=bpf $(LLC_FLAGS) -filetype=obj -o $@ 244ifeq ($(DWARF2BTF),y) 245 $(BTF_PAHOLE) -J $@ 246endif 247