# Copyright 2020 The Android KVM Authors
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

SELF := $(abspath $(lastword $(MAKEFILE_LIST)))

CPUS ?= $(shell nproc)
MAKEFLAGS += --jobs=$(CPUS)
SHELL ?= $(shell which bash)

##
## Folders
##
ROOT_DIR := $(CURDIR)

OUT_DIR := $(ROOT_DIR)/out

# DIST_DIR: target directory for artifacts and logs.
# The CI build (pKVM Busytown) uses it to separate artifacts from other
# temporary build files, which are placed in in OUT_DIR.
# For other users, OUT_DIR and DIST_DIR are typically the same.
DIST_DIR ?= $(OUT_DIR)

# Copy specified file or directory only if OUT_DIR and DIST_DIR aren't the same.
#
# Parameters:
# $(1): Source files or directories (to be copied recursively)
# $(2): Destination directory (is created if it doesn't exist)
ifneq ($(abspath $(OUT_DIR)), $(abspath $(DIST_DIR)))
define copy_to_dist
	mkdir -p $(2) && cp -r $(1) $(2)
endef
endif

LINUX_OUT := $(OUT_DIR)/linux
LINUX_DIST := $(DIST_DIR)/linux
SCRIPTS_DIR := $(ROOT_DIR)/build

include $(SCRIPTS_DIR)/toolchain.mk

##
## Common options
##
VERBOSE ?= 0
ARCH = arm64

LINUX_OUT_IMAGE := $(LINUX_OUT)/arch/arm64/boot/Image
LINUX_OUT_MODULES := $(LINUX_OUT)/modules_install
LINUX_OUT_MODULES_DEP := $(LINUX_OUT)/modules_install.stamp

# KERNEL_IMAGE/MODULES can be set to use own custom kernel image.
KERNEL_IMAGE ?= $(LINUX_OUT_IMAGE)
KERNEL_MODULES ?= $(LINUX_OUT_MODULES)
KERNEL_MODULES_DEP ?= $(LINUX_OUT_MODULES_DEP)

##
## Toolchain options and variables
##

# Specifies which toolchain of the prebuilt toolchains to use.
# Can be either clang, gcc-5.1, or gcc-9.2.
# GCC will always use the latest version for building everything else other
# than the kernel.
TOOLCHAIN ?= clang
$(eval $(call define_toolchain,$(TOOLCHAIN)))

##
## Common targets
##

.DEFAULT_GOAL := default

.PHONY: default
default: kvm-unit-tests linux

.PHONY: clean
clean: buildroot_clean kvm-unit-tests_clean linux_clean

.PHONY: distclean
distclean:
	- rm -rf $(OUT_DIR) $(DIST_DIR)

.PHONY: all
all: buildroot kvm-unit-tests linux

.PHONY: help
help:
	@echo 'Generic Targets:'
	@echo '   default              - builds all generic targets except for buildroot'
	@echo '   all                  - builds all generic targets'
	@echo '   buildroot            - the buildroot rootfs image as well as the host qemu'
	@echo '   kvm-unit-tests       - the kvm-unit-tests'
	@echo '   linux                - the linux kernel'
	@echo ''
	@echo 'Clean Targets:'
	@echo '   clean                - cleans all, but keeps the prebuilts'
	@echo '   distclean            - distclean for all targets'
	@echo '   buildroot_clean      - the buildroot rootfs image as well as the host qemu'
	@echo '   kvm-unit-tests_clean - the kvm-unit-tests'
	@echo '   linux_clean          - the linux kernel'
	@echo ''
	@echo 'Test Targets:'
	@echo '   test                 - runs all tests in qemu-aarch64 simulated environment'
	@echo '   test-kut             - runs all kvm-unit-tests in qemu-aarch64 simulated environment'
	@echo '   test-list            - lists all test targets'
	@echo ''
	@echo 'Test Parameters:'
	@echo '   CROSVM_TAR_GZ        - path to a custom cvd-host_package.tar.gz'
	@echo '                          (default: uses a pre-built version)'
	@echo '   VM_IMAGE             - path to an image to be used by the VMM to boot the VM'
	@echo '                          (default: uses the host image)'
	@echo ''
	@echo 'Test Flags:'
	@echo '   VERBOSE=[0|1]        - prints the verbose output of the scripts running the test'
	@echo '                          (default: 0)'
	@echo '   QUIET=[0|1]          - redirects the output to a file instead of stdout'
	@echo '                          (default: 1)'
	@echo '   GDB=[0|1]            - makes the started test wait for a GDB connection'
	@echo '                          (default: 0)'
	@echo ''
	@echo 'Misc Targets:'
	@echo '   update-prebuilts     - generates/update the prebuilt rootfs image (aarch64) and the qemu host (aarch64)'


##
## Buildroot
##

BR_DEFCONFIG ?= qemu_aarch64_virt_kvmunittests_defconfig
BR_VERBOSE ?= $(VERBOSE)

BR_SRC := $(ROOT_DIR)/buildroot
BR_OUT := $(OUT_DIR)/buildroot
BR_MAKE := $(MAKE) -C $(BR_SRC) V=$(BR_VERBOSE) O=$(BR_OUT)

.PHONY: buildroot
buildroot:
	+ $(BR_MAKE) $(BR_DEFCONFIG)
	+ $(BR_MAKE) all

.PHONY: buildroot_clean
buildroot_clean:
	+ $(BR_MAKE) clean


##
## kvm-unit-tests
##
KUT_SRC := $(ROOT_DIR)/kvm-unit-tests
KUT_OUT := $(OUT_DIR)/kvm-unit-tests
KUT_DIST := $(DIST_DIR)/kvm-unit-tests
KUT_STAMP := $(KUT_OUT)/kvm-unit-tests.stamp

ifneq ($(TOOLCHAIN_IS_LEGACY),1)
KUT_TOOLCHAIN ?= $(TOOLCHAIN)
else
KUT_TOOLCHAIN ?= gcc-9.2
endif
$(eval $(call define_toolchain,$(KUT_TOOLCHAIN),KUT_))

ifeq ($(KUT_TOOLCHAIN_IS_LLVM),1)
KUT_CFLAGS += --target=$(KUT_TARGET) -fpic
endif

.PHONY: kvm-unit-tests
kvm-unit-tests $(KUT_STAMP):
	mkdir -p $(KUT_OUT)
	cd $(KUT_OUT) && \
		$(KUT_SRC)/configure \
			--erratatxt=$(KUT_SRC)/errata.txt \
			--prefix=$(KUT_OUT) --arch=$(ARCH) \
			--cc=$(KUT_CC) --ld=$(KUT_LD) \
			--objcopy=$(KUT_OBJCOPY) --objdump=$(KUT_OBJDUMP)
	COMMON_CFLAGS="$(KUT_CFLAGS)" \
		$(MAKE) -C $(KUT_OUT) standalone
	$(call copy_to_dist, $(KUT_OUT)/tests, $(KUT_DIST))
	touch $(KUT_STAMP)

.PHONY: kvm-unit-tests_clean
kvm-unit-tests_clean:
	- rm -f $(KUT_STAMP)
	- $(MAKE) -C $(KUT_OUT) clean


##
## Linux kernel
##
LINUX_DEFCONFIG ?= defconfig
LINUX_VERBOSE ?= $(VERBOSE)
LINUX_SRC ?= $(ROOT_DIR)/linux
LINUX_VMLINUX = $(LINUX_OUT)/vmlinux
LINUX_CONFIG := $(LINUX_OUT)/.config
LINUX_DIST_FILES = $(LINUX_CONFIG) $(LINUX_VMLINUX) $(KERNEL_IMAGE)
LINUX_LSMOD_TXT := $(LINUX_OUT)/lsmod.txt

LINUX_TOOLCHAIN ?= $(TOOLCHAIN)
$(eval $(call define_toolchain,$(LINUX_TOOLCHAIN),LINUX_))

ifeq ($(LINUX_TOOLCHAIN_IS_LLVM),1)
LINUX_EXTRA += LLVM=1 LLVM_IAS=1
endif

LINUX_MAKE := \
	PATH=$(LINUX_TOOLCHAIN_BIN):$(PATH) \
	ARCH=$(ARCH) \
	CROSS_COMPILE="$(LINUX_TARGET)-" \
	$(MAKE) \
	$(LINUX_EXTRA) \
	CC=$(LINUX_CC) \
	LD=$(LINUX_LD) \
	OBJCOPY=$(LINUX_OBJCOPY) \
	OBJDUMP=$(LINUX_OBJDUMP) \
	-C $(LINUX_SRC) \
	V=$(LINUX_VERBOSE) \
	O=$(LINUX_OUT)

LINUX_MODULES := \
	TEST_PRINTF

.PHONY: linux_defconfig
linux_defconfig $(LINUX_CONFIG):
	+ $(LINUX_MAKE) $(LINUX_DEFCONFIG)
	# Disable all modules, then selectively enable those in LINUX_MODULES.
	@ echo > $(LINUX_LSMOD_TXT)
	+ $(LINUX_MAKE) LSMOD=$(LINUX_LSMOD_TXT) localmodconfig
	$(LINUX_SRC)/scripts/config --file $(LINUX_CONFIG) $(addprefix -m CONFIG_,$(LINUX_MODULES))

.PHONY: linux_menuconfig
linux_menuconfig: $(LINUX_CONFIG)
	+ $(LINUX_MAKE) menuconfig

.PHONY: linux
linux: $(LINUX_CONFIG)
	+ $(LINUX_MAKE)
	$(call copy_to_dist, $(LINUX_DIST_FILES), $(LINUX_DIST))

.PHONY: linux_image
linux_image $(LINUX_OUT_IMAGE): $(LINUX_CONFIG)
	+ $(LINUX_MAKE) Image.gz
	$(call copy_to_dist, $(LINUX_DIST_FILES), $(LINUX_DIST))

.PHONY: linux_modules
linux_modules $(LINUX_OUT_MODULES_DEP): $(LINUX_OUT_IMAGE)
	@ rm -rf $(LINUX_OUT_MODULES)
	+ $(LINUX_MAKE) modules
	+ $(LINUX_MAKE) INSTALL_MOD_PATH=$(LINUX_OUT_MODULES) modules_install
	@ find $(LINUX_OUT_MODULES) -type f | sort | \
		xargs sha1sum > $(LINUX_OUT_MODULES_DEP).tmp
	@ cmp $(LINUX_OUT_MODULES_DEP).tmp $(LINUX_OUT_MODULES_DEP) || \
		mv $(LINUX_OUT_MODULES_DEP).tmp $(LINUX_OUT_MODULES_DEP)

.PHONY: linux_clean
linux_clean:
	+ $(LINUX_MAKE) mrproper


##
## Generating/Updating prebuilts
##

PREBUILTS_CROSVM_EXT4 := prebuilts/linux-aarch64/images/crosvm.ext4
PREBUILTS_ROOTFS_EXT4 := prebuilts/linux-aarch64/images/rootfs.ext4
PREBUILTS_QEMU_ROM := prebuilts/linux-aarch64/images/efi-virtio.rom
PREBUILTS_QEMU_BIN := prebuilts/linux-x86/qemu

CUSTOM_CROSVM_EXT4 := $(OUT_DIR)/images/crosvm.ext4

ifeq ($(CROSVM_TAR_GZ),)
CROSVM_EXT4 := $(PREBUILTS_CROSVM_EXT4)
else
CROSVM_EXT4 := $(CUSTOM_CROSVM_EXT4)
endif

.PHONY:update-prebuilts
update-prebuilts: \
	$(PREBUILTS_ROOTFS_EXT4) \
	update-prebuilts-crosvm \
	$(PREBUILTS_QEMU_ROM) \
	$(PREBUILTS_QEMU_BIN)

$(PREBUILTS_ROOTFS_EXT4): buildroot
	mkdir -p $(shell dirname $@)
	cp $(BR_OUT)/images/rootfs.ext4 $@

$(PREBUILTS_QEMU_ROM): buildroot
	mkdir -p $(shell dirname $@)
	cp $(BR_OUT)/per-package/host-qemu/host/share/qemu/efi-virtio.rom $@

CF_DOWNLOAD_AOSP_SH := $(ROOT_DIR)/build/cuttlefish/download-aosp.sh

# A PHONY target is necessary for allowing the user to update the archive
# because, as we are downloading it from a remote server, make dependencies are
# unable to express the local-->remote dependency:
.PHONY: update-prebuilts-crosvm
update-prebuilts-crosvm $(PREBUILTS_CROSVM_TAR_GZ):
	@rm -f $(PREBUILTS_CROSVM_TAR_GZ)  # else, wget will create "$@.1"
	cd $(dir $(PREBUILTS_CROSVM_TAR_GZ)) && $(CF_DOWNLOAD_AOSP_SH) -XCa arm64
	@touch -c $(PREBUILTS_CROSVM_TAR_GZ)  # wget doesn't set timestamp to now

CROSVM_IMG_SIZE_MB := 1024

$(CUSTOM_CROSVM_EXT4): TMP_DIR := $(shell mktemp -d)
$(CUSTOM_CROSVM_EXT4): $(CROSVM_TAR_GZ)
	mkdir -p $(@D)
	cd $(TMP_DIR) && tar xzvf $(abspath $<)
	dd if=/dev/zero of=$@.tmp bs=1M count=$(CROSVM_IMG_SIZE_MB)
	mkfs.ext4 -d $(TMP_DIR) $@.tmp
	rm -rf $(TMP_DIR)
	mv $@.tmp $@

# The qemu binary
.PHONY:$(PREBUILTS_QEMU_BIN)
$(PREBUILTS_QEMU_BIN):
	- rm -rf $@
	${SCRIPTS_DIR}/aarch64/build_qemu.sh $(OUT_DIR)/qemu ${TOOLCHAIN_BIN}
	mkdir -p $@/bin
	cp $(OUT_DIR)/qemu/qemu-system-aarch64 $@/bin

##
## Run tests
##

KVM_MODES := vhe nvhe pkvm
hyphensuffix = $(lastword $(subst -, ,$(1)))

RUN_TEST_SH := $(SCRIPTS_DIR)/kvm-unit-tests/run_test.sh
RUN_TEST = $(RUN_TEST_SH) \
		-d $@ \
		-M $(call hyphensuffix,$@) \
		-k "$(KERNEL_IMAGE)" \
		$(RUN_TEST_ARGS) "$(RUN_TEST_HOST_SH)" \
		-- \
		-D modules:${KERNEL_MODULES}/lib/modules \
		$(RUN_TEST_QEMU_ARGS)

ifeq ($(VERBOSE),1)
RUN_TEST_ARGS += -v
endif

ifneq ($(QUIET),0)
RUN_TEST_ARGS += -o "$(RUN_TEST_LOG_DIR)/$@.log"
endif

ifeq ($(GDB),1)
# RUN_TEST_SH defaults to no-timeout when -G is passed but -t forces one:
RUN_TEST_ARGS += -G
else
# Without -G, RUN_TEST_SH defaults to a non-zero timeout duration.
# RUN_TEST_TIMEOUT should be use if a specific value is wanted (see 'man timeout').
# In particular, RUN_TEST_TIMEOUT=0 prevents the test from timing out.
RUN_TEST_ARGS += $(if $(RUN_TEST_TIMEOUT),-t ,)$(RUN_TEST_TIMEOUT)
endif

# Root test targets. Dynamically generated per-test targets
# will add themselves as dependencies of these.
.PHONY: test test-list
test:
test-list:

#
# kvm-unit-tests
#

KUT_RUN_TEST = $(RUN_TEST_SH)
KUT_GEN_MAKEFILE := $(SCRIPTS_DIR)/kvm-unit-tests/gen_makefile.sh
KUT_MAKEFILE := $(OUT_DIR)/Makefile.kvm-unit-tests
KUT_TEST_DIR := $(KUT_OUT)/tests
KUT_LOG_DIR := $(DIST_DIR)/logs/kvm-unit-tests/

# Exclude tests that require user interaction or are known to fail.
KUT_EXCLUDE := (.+migrat.+)|(gicv2-.+)|(pmu-event-introspection)|(micro-bench)

# Generate a Makefile with targets per test and configuration.
# Pass in variable/target names from this Makefile that the
# generated Makefile will refer to.
$(KUT_MAKEFILE): $(SELF) $(KUT_GEN_MAKEFILE) $(KUT_STAMP)
	@ mkdir -p $(shell dirname $@)
	@ $(KUT_GEN_MAKEFILE)				\
		$(KUT_TEST_DIR) "$(KUT_EXCLUDE)"	\
		KERNEL_IMAGE KUT_LOG_DIR test test-list	\
		> $@.tmp
	@ mv $@.tmp $@
include $(KUT_MAKEFILE)

#
# Basic boot tests in the various arm64 KVM modes
#

BOOT_TESTS := $(addprefix test-boot-,$(KVM_MODES))

.PHONY: test-boot
test-boot: $(BOOT_TESTS)

TEST_LISTS += test-list-boot
test-list-boot: LISTED_TESTS = $(BOOT_TESTS)

TESTS += $(BOOT_TESTS)
$(BOOT_TESTS): RUN_TEST_LOG_DIR = $(DIST_DIR)/logs/boot
$(BOOT_TESTS): RUN_TEST_HOST_SH = $(SCRIPTS_DIR)/aarch64/test_boot.sh
$(BOOT_TESTS): RUN_TEST_QEMU_ARGS = -a "boot_test_mode=$(call hyphensuffix,$@)"

#
# CrosVM Hello World test
#

CROSVM_HELLOWORLD_TESTS := $(addprefix test-crosvm-helloworld-,$(KVM_MODES))

VM_IMAGE ?= $(KERNEL_IMAGE)

.PHONY: test-crosvm-helloworld
test-crosvm-helloworld: $(CROSVM_HELLOWORLD_TESTS)

TEST_LISTS += test-list-crosvm-helloworld
test-list-crosvm-helloworld: LISTED_TESTS = $(CROSVM_HELLOWORLD_TESTS)

TESTS += $(CROSVM_HELLOWORLD_TESTS)
$(CROSVM_HELLOWORLD_TESTS): $(CROSVM_EXT4)
$(CROSVM_HELLOWORLD_TESTS): RUN_TEST_LOG_DIR = $(DIST_DIR)/logs/crosvm/helloworld
$(CROSVM_HELLOWORLD_TESTS): RUN_TEST_HOST_SH = $(SCRIPTS_DIR)/crosvm/helloworld/host.sh
$(CROSVM_HELLOWORLD_TESTS): RUN_TEST_QEMU_ARGS = \
		-s 4 \
		-R $(SCRIPTS_DIR)/crosvm/helloworld/guest.sh \
		-R $(VM_IMAGE) \
		-R $(PREBUILTS_ROOTFS_EXT4) \
		-R $(CROSVM_EXT4)
$(CROSVM_HELLOWORLD_TESTS): RUN_TEST_TIMEOUT := 300s

.PHONY test: $(TESTS)
$(TESTS): $(KERNEL_IMAGE) $(KERNEL_MODULES_DEP)
	@ $(RUN_TEST)
.PHONY test-list: $(TEST_LISTS)
$(TEST_LISTS):
	@ for x in $(LISTED_TESTS); do echo $$x; done