1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright (C) 2024, Intel, Inc
  4 *
  5 * Author:
  6 * Isaku Yamahata <isaku.yamahata at gmail.com>
  7 */
  8#include <linux/sizes.h>
  9
 10#include <test_util.h>
 11#include <kvm_util.h>
 12#include <processor.h>
 13
 14/* Arbitrarily chosen values */
 15#define TEST_SIZE		(SZ_2M + PAGE_SIZE)
 16#define TEST_NPAGES		(TEST_SIZE / PAGE_SIZE)
 17#define TEST_SLOT		10
 18
 19static void guest_code(uint64_t base_gpa)
 20{
 21	volatile uint64_t val __used;
 22	int i;
 23
 24	for (i = 0; i < TEST_NPAGES; i++) {
 25		uint64_t *src = (uint64_t *)(base_gpa + i * PAGE_SIZE);
 26
 27		val = *src;
 28	}
 29
 30	GUEST_DONE();
 31}
 32
 33static void pre_fault_memory(struct kvm_vcpu *vcpu, u64 gpa, u64 size,
 34			     u64 left)
 35{
 36	struct kvm_pre_fault_memory range = {
 37		.gpa = gpa,
 38		.size = size,
 39		.flags = 0,
 40	};
 41	u64 prev;
 42	int ret, save_errno;
 43
 44	do {
 45		prev = range.size;
 46		ret = __vcpu_ioctl(vcpu, KVM_PRE_FAULT_MEMORY, &range);
 47		save_errno = errno;
 48		TEST_ASSERT((range.size < prev) ^ (ret < 0),
 49			    "%sexpecting range.size to change on %s",
 50			    ret < 0 ? "not " : "",
 51			    ret < 0 ? "failure" : "success");
 52	} while (ret >= 0 ? range.size : save_errno == EINTR);
 53
 54	TEST_ASSERT(range.size == left,
 55		    "Completed with %lld bytes left, expected %" PRId64,
 56		    range.size, left);
 57
 58	if (left == 0)
 59		__TEST_ASSERT_VM_VCPU_IOCTL(!ret, "KVM_PRE_FAULT_MEMORY", ret, vcpu->vm);
 60	else
 61		/* No memory slot causes RET_PF_EMULATE. it results in -ENOENT. */
 62		__TEST_ASSERT_VM_VCPU_IOCTL(ret && save_errno == ENOENT,
 63					    "KVM_PRE_FAULT_MEMORY", ret, vcpu->vm);
 64}
 65
 66static void __test_pre_fault_memory(unsigned long vm_type, bool private)
 67{
 68	const struct vm_shape shape = {
 69		.mode = VM_MODE_DEFAULT,
 70		.type = vm_type,
 71	};
 72	struct kvm_vcpu *vcpu;
 73	struct kvm_run *run;
 74	struct kvm_vm *vm;
 75	struct ucall uc;
 76
 77	uint64_t guest_test_phys_mem;
 78	uint64_t guest_test_virt_mem;
 79	uint64_t alignment, guest_page_size;
 80
 81	vm = vm_create_shape_with_one_vcpu(shape, &vcpu, guest_code);
 82
 83	alignment = guest_page_size = vm_guest_mode_params[VM_MODE_DEFAULT].page_size;
 84	guest_test_phys_mem = (vm->max_gfn - TEST_NPAGES) * guest_page_size;
 85#ifdef __s390x__
 86	alignment = max(0x100000UL, guest_page_size);
 87#else
 88	alignment = SZ_2M;
 89#endif
 90	guest_test_phys_mem = align_down(guest_test_phys_mem, alignment);
 91	guest_test_virt_mem = guest_test_phys_mem & ((1ULL << (vm->va_bits - 1)) - 1);
 92
 93	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
 94				    guest_test_phys_mem, TEST_SLOT, TEST_NPAGES,
 95				    private ? KVM_MEM_GUEST_MEMFD : 0);
 96	virt_map(vm, guest_test_virt_mem, guest_test_phys_mem, TEST_NPAGES);
 97
 98	if (private)
 99		vm_mem_set_private(vm, guest_test_phys_mem, TEST_SIZE);
100	pre_fault_memory(vcpu, guest_test_phys_mem, SZ_2M, 0);
101	pre_fault_memory(vcpu, guest_test_phys_mem + SZ_2M, PAGE_SIZE * 2, PAGE_SIZE);
102	pre_fault_memory(vcpu, guest_test_phys_mem + TEST_SIZE, PAGE_SIZE, PAGE_SIZE);
103
104	vcpu_args_set(vcpu, 1, guest_test_virt_mem);
105	vcpu_run(vcpu);
106
107	run = vcpu->run;
108	TEST_ASSERT(run->exit_reason == KVM_EXIT_IO,
109		    "Wanted KVM_EXIT_IO, got exit reason: %u (%s)",
110		    run->exit_reason, exit_reason_str(run->exit_reason));
111
112	switch (get_ucall(vcpu, &uc)) {
113	case UCALL_ABORT:
114		REPORT_GUEST_ASSERT(uc);
115		break;
116	case UCALL_DONE:
117		break;
118	default:
119		TEST_FAIL("Unknown ucall 0x%lx.", uc.cmd);
120		break;
121	}
122
123	kvm_vm_free(vm);
124}
125
126static void test_pre_fault_memory(unsigned long vm_type, bool private)
127{
128	if (vm_type && !(kvm_check_cap(KVM_CAP_VM_TYPES) & BIT(vm_type))) {
129		pr_info("Skipping tests for vm_type 0x%lx\n", vm_type);
130		return;
131	}
132
133	__test_pre_fault_memory(vm_type, private);
134}
135
136int main(int argc, char *argv[])
137{
138	TEST_REQUIRE(kvm_check_cap(KVM_CAP_PRE_FAULT_MEMORY));
139
140	test_pre_fault_memory(0, false);
141#ifdef __x86_64__
142	test_pre_fault_memory(KVM_X86_SW_PROTECTED_VM, false);
143	test_pre_fault_memory(KVM_X86_SW_PROTECTED_VM, true);
144#endif
145	return 0;
146}