bpf-headers: add a package with kernel headers for ebpf

[openwrt/staging/thess.git] / include / bpf.mk

diff --git a/include/bpf.mk b/include/bpf.mk
new file mode 100644 (file)
index 0000000..3dc65c7
--- /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
+