[RFC PATCH 8/8] KVM: selftests: x86: Add test for KVM_MAP_MEMORY

[isaku . yamahata]

From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>

Add a test case to exercise KVM_MAP_MEMORY and run the guest to access
pre-populated area. It tests KVM_MAP_MEMORY ioctl for KVM_X86_DEFAULT_VM
and KVM_X86_SW_PROTECTED_VM.  The other VM type is just for future place
hodler.

Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
---
 tools/include/uapi/linux/kvm.h                |  14 ++
 tools/testing/selftests/kvm/Makefile          |   1 +
 .../selftests/kvm/x86_64/map_memory_test.c    | 136 ++++++++++++++++++
 3 files changed, 151 insertions(+)
 create mode 100644 tools/testing/selftests/kvm/x86_64/map_memory_test.c

diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h
index c3308536482b..ea8d3cf840ab 100644
--- a/tools/include/uapi/linux/kvm.h
+++ b/tools/include/uapi/linux/kvm.h
@@ -2227,4 +2227,18 @@ struct kvm_create_guest_memfd {
 	__u64 reserved[6];
 };
 
+#define KVM_MAP_MEMORY	_IOWR(KVMIO, 0xd5, struct kvm_memory_mapping)
+
+#define KVM_MEMORY_MAPPING_FLAG_WRITE	_BITULL(0)
+#define KVM_MEMORY_MAPPING_FLAG_EXEC	_BITULL(1)
+#define KVM_MEMORY_MAPPING_FLAG_USER	_BITULL(2)
+#define KVM_MEMORY_MAPPING_FLAG_PRIVATE _BITULL(3)
+
+struct kvm_memory_mapping {
+	__u64 base_gfn;
+	__u64 nr_pages;
+	__u64 flags;
+	__u64 source;
+};
+
 #endif /* __LINUX_KVM_H */
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index da20e6bb43ed..baef461ed38a 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -142,6 +142,7 @@ TEST_GEN_PROGS_x86_64 += set_memory_region_test
 TEST_GEN_PROGS_x86_64 += steal_time
 TEST_GEN_PROGS_x86_64 += kvm_binary_stats_test
 TEST_GEN_PROGS_x86_64 += system_counter_offset_test
+TEST_GEN_PROGS_x86_64 += x86_64/map_memory_test
 
 # Compiled outputs used by test targets
 TEST_GEN_PROGS_EXTENDED_x86_64 += x86_64/nx_huge_pages_test
diff --git a/tools/testing/selftests/kvm/x86_64/map_memory_test.c b/tools/testing/selftests/kvm/x86_64/map_memory_test.c
new file mode 100644
index 000000000000..9480c6c89226
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/map_memory_test.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 202r, Intel, Inc
+ *
+ * Author:
+ * Isaku Yamahata <isaku.yamahata at gmail.com>
+ */
+#include <linux/sizes.h>
+
+#include <test_util.h>
+#include <kvm_util.h>
+#include <processor.h>
+
+/* Arbitrarily chosen value. Pick 3G */
+#define TEST_GVA		0xc0000000
+#define TEST_GPA		TEST_GVA
+#define TEST_SIZE		(SZ_2M + PAGE_SIZE)
+#define TEST_NPAGES		(TEST_SIZE / PAGE_SIZE)
+#define TEST_SLOT		10
+
+static void guest_code(uint64_t base_gpa)
+{
+	volatile uint64_t val __used;
+	int i;
+
+	for (i = 0; i < TEST_NPAGES; i++) {
+		uint64_t *src = (uint64_t *)(base_gpa + i * PAGE_SIZE);
+
+		val = *src;
+	}
+
+	GUEST_DONE();
+}
+
+static void map_memory(struct kvm_vcpu *vcpu, u64 base_gfn, u64 nr_pages,
+		       u64 source, bool should_success)
+{
+	struct kvm_memory_mapping mapping = {
+		.base_gfn = base_gfn,
+		.nr_pages = nr_pages,
+		.flags = KVM_MEMORY_MAPPING_FLAG_WRITE,
+		.source = source,
+	};
+	int ret;
+
+	do {
+		ret = __vcpu_ioctl(vcpu, KVM_MAP_MEMORY, &mapping);
+	} while (ret && errno == EAGAIN);
+
+	if (should_success) {
+		__TEST_ASSERT_VM_VCPU_IOCTL(!ret, "KVM_MAP_MEMORY", ret, vcpu->vm);
+	} else {
+		__TEST_ASSERT_VM_VCPU_IOCTL(ret && errno == EFAULT,
+					    "KVM_MAP_MEMORY", ret, vcpu->vm);
+	}
+}
+
+static void __test_map_memory(unsigned long vm_type, bool private, bool use_source)
+{
+	const struct vm_shape shape = {
+		.mode = VM_MODE_DEFAULT,
+		.type = vm_type,
+	};
+	struct kvm_vcpu *vcpu;
+	struct kvm_run *run;
+	struct kvm_vm *vm;
+	struct ucall uc;
+	u64 source;
+
+	vm = vm_create_shape_with_one_vcpu(shape, &vcpu, guest_code);
+	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
+				    TEST_GPA, TEST_SLOT, TEST_NPAGES,
+				    private ? KVM_MEM_GUEST_MEMFD : 0);
+	virt_map(vm, TEST_GVA, TEST_GPA, TEST_NPAGES);
+
+	if (private)
+		vm_mem_set_private(vm, TEST_GPA, TEST_SIZE);
+
+	source = use_source ? TEST_GVA: 0;
+	map_memory(vcpu, TEST_GPA / PAGE_SIZE, SZ_2M / PAGE_SIZE, source, true);
+	source = use_source ? TEST_GVA + SZ_2M: 0;
+	map_memory(vcpu, (TEST_GPA + SZ_2M) / PAGE_SIZE, 1, source, true);
+
+	source = use_source ? TEST_GVA + TEST_SIZE : 0;
+	map_memory(vcpu, (TEST_GPA + TEST_SIZE) / PAGE_SIZE, 1, source, false);
+
+	vcpu_args_set(vcpu, 1, TEST_GVA);
+	vcpu_run(vcpu);
+
+	run = vcpu->run;
+	TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
+		    "Wanted KVM_EXIT_IO, got exit reason: %u (%s)",
+		    run->exit_reason, exit_reason_str(run->exit_reason));
+
+	switch (get_ucall(vcpu, &uc)) {
+	case UCALL_ABORT:
+		REPORT_GUEST_ASSERT(uc);
+		break;
+	case UCALL_DONE:
+		break;
+	default:
+		TEST_FAIL("Unknown ucall 0x%lx.", uc.cmd);
+		break;
+	}
+
+	kvm_vm_free(vm);
+}
+
+static void test_map_memory(unsigned long vm_type, bool use_source)
+{
+	if (!(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(vm_type))) {
+		pr_info("Skipping tests for vm_type 0x%lx\n", vm_type);
+		return;
+	}
+
+	__test_map_memory(vm_type, false, use_source);
+	__test_map_memory(vm_type, true, use_source);
+}
+
+int main(int argc, char *argv[])
+{
+	TEST_REQUIRE(kvm_check_cap(KVM_CAP_MAP_MEMORY));
+
+	__test_map_memory(KVM_X86_DEFAULT_VM, false, false);
+	test_map_memory(KVM_X86_SW_PROTECTED_VM, false);
+#ifdef KVM_X86_SEV_VM
+	test_map_memory(KVM_X86_SEV_VM, false);
+#endif
+#ifdef KVM_X86_SEV_ES_VM
+	test_map_memory(KVM_X86_SEV_ES_VM, false);
+#endif
+#ifdef KVM_X86_TDX_VM
+	test_map_memory(KVM_X86_TDX_VM, true);
+#endif
+	return 0;
+}
-- 
2.25.1