// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2021, Google LLC.
*
* Tests for adjusting the KVM clock from userspace
*/
#include <asm/kvm_para.h>
#include <asm/pvclock.h>
#include <asm/pvclock-abi.h>
#include <stdint.h>
#include <string.h>
#include <sys/stat.h>
#include <time.h>
#include "test_util.h"
#include "kvm_util.h"
#include "processor.h"
struct test_case {
uint64_t kvmclock_base;
int64_t realtime_offset;
};
static struct test_case test_cases[] = {
{ .kvmclock_base = 0 },
{ .kvmclock_base = 180 * NSEC_PER_SEC },
{ .kvmclock_base = 0, .realtime_offset = -180 * NSEC_PER_SEC },
{ .kvmclock_base = 0, .realtime_offset = 180 * NSEC_PER_SEC },
};
#define GUEST_SYNC_CLOCK(__stage, __val) \
GUEST_SYNC_ARGS(__stage, __val, 0, 0, 0)
static void guest_main(vm_paddr_t pvti_pa, struct pvclock_vcpu_time_info *pvti)
{
int i;
wrmsr(MSR_KVM_SYSTEM_TIME_NEW, pvti_pa | KVM_MSR_ENABLED);
for (i = 0; i < ARRAY_SIZE(test_cases); i++)
GUEST_SYNC_CLOCK(i, __pvclock_read_cycles(pvti, rdtsc()));
}
#define EXPECTED_FLAGS (KVM_CLOCK_REALTIME | KVM_CLOCK_HOST_TSC)
static inline void assert_flags(struct kvm_clock_data *data)
{
TEST_ASSERT((data->flags & EXPECTED_FLAGS) == EXPECTED_FLAGS,
"unexpected clock data flags: %x (want set: %x)",
data->flags, EXPECTED_FLAGS);
}
static void handle_sync(struct ucall *uc, struct kvm_clock_data *start,
struct kvm_clock_data *end)
{
uint64_t obs, exp_lo, exp_hi;
obs = uc->args[2];
exp_lo = start->clock;
exp_hi = end->clock;
assert_flags(start);
assert_flags(end);
TEST_ASSERT(exp_lo <= obs && obs <= exp_hi,
"unexpected kvm-clock value: %"PRIu64" expected range: [%"PRIu64", %"PRIu64"]",
obs, exp_lo, exp_hi);
pr_info("kvm-clock value: %"PRIu64" expected range [%"PRIu64", %"PRIu64"]\n",
obs, exp_lo, exp_hi);
}
static void handle_abort(struct ucall *uc)
{
REPORT_GUEST_ASSERT(*uc);
}
static void setup_clock(struct kvm_vm *vm, struct test_case *test_case)
{
struct kvm_clock_data data;
memset(&data, 0, sizeof(data));
data.clock = test_case->kvmclock_base;
if (test_case->realtime_offset) {
struct timespec ts;
int r;
data.flags |= KVM_CLOCK_REALTIME;
do {
r = clock_gettime(CLOCK_REALTIME, &ts);
if (!r)
break;
} while (errno == EINTR);
TEST_ASSERT(!r, "clock_gettime() failed: %d", r);
data.realtime = ts.tv_sec * NSEC_PER_SEC;
data.realtime += ts.tv_nsec;
data.realtime += test_case->realtime_offset;
}
vm_ioctl(vm, KVM_SET_CLOCK, &data);
}
static void enter_guest(struct kvm_vcpu *vcpu)
{
struct kvm_clock_data start, end;
struct kvm_vm *vm = vcpu->vm;
struct ucall uc;
int i;
for (i = 0; i < ARRAY_SIZE(test_cases); i++) {
setup_clock(vm, &test_cases[i]);
vm_ioctl(vm, KVM_GET_CLOCK, &start);
vcpu_run(vcpu);
vm_ioctl(vm, KVM_GET_CLOCK, &end);
TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_IO);
switch (get_ucall(vcpu, &uc)) {
case UCALL_SYNC:
handle_sync(&uc, &start, &end);
break;
case UCALL_ABORT:
handle_abort(&uc);
return;
default:
TEST_ASSERT(0, "unhandled ucall: %ld", uc.cmd);
}
}
}
int main(void)
{
struct kvm_vcpu *vcpu;
vm_vaddr_t pvti_gva;
vm_paddr_t pvti_gpa;
struct kvm_vm *vm;
int flags;
flags = kvm_check_cap(KVM_CAP_ADJUST_CLOCK);
TEST_REQUIRE(flags & KVM_CLOCK_REALTIME);
TEST_REQUIRE(sys_clocksource_is_based_on_tsc());
vm = vm_create_with_one_vcpu(&vcpu, guest_main);
pvti_gva = vm_vaddr_alloc(vm, getpagesize(), 0x10000);
pvti_gpa = addr_gva2gpa(vm, pvti_gva);
vcpu_args_set(vcpu, 2, pvti_gpa, pvti_gva);
enter_guest(vcpu);
kvm_vm_free(vm);
}