| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * KVM dirty page logging test |
| * |
| * Copyright (C) 2018, Red Hat, Inc. |
| */ |
| |
| #define _GNU_SOURCE /* for program_invocation_name */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <time.h> |
| #include <pthread.h> |
| #include <linux/bitmap.h> |
| #include <linux/bitops.h> |
| |
| #include "test_util.h" |
| #include "kvm_util.h" |
| #include "processor.h" |
| |
| #define DEBUG printf |
| |
| #define VCPU_ID 1 |
| |
| /* The memory slot index to track dirty pages */ |
| #define TEST_MEM_SLOT_INDEX 1 |
| |
| /* Default guest test memory offset, 1G */ |
| #define DEFAULT_GUEST_TEST_MEM 0x40000000 |
| |
| /* How many pages to dirty for each guest loop */ |
| #define TEST_PAGES_PER_LOOP 1024 |
| |
| /* How many host loops to run (one KVM_GET_DIRTY_LOG for each loop) */ |
| #define TEST_HOST_LOOP_N 32UL |
| |
| /* Interval for each host loop (ms) */ |
| #define TEST_HOST_LOOP_INTERVAL 10UL |
| |
| /* |
| * Guest/Host shared variables. Ensure addr_gva2hva() and/or |
| * sync_global_to/from_guest() are used when accessing from |
| * the host. READ/WRITE_ONCE() should also be used with anything |
| * that may change. |
| */ |
| static uint64_t host_page_size; |
| static uint64_t guest_page_size; |
| static uint64_t guest_num_pages; |
| static uint64_t random_array[TEST_PAGES_PER_LOOP]; |
| static uint64_t iteration; |
| |
| /* |
| * Guest physical memory offset of the testing memory slot. |
| * This will be set to the topmost valid physical address minus |
| * the test memory size. |
| */ |
| static uint64_t guest_test_phys_mem; |
| |
| /* |
| * Guest virtual memory offset of the testing memory slot. |
| * Must not conflict with identity mapped test code. |
| */ |
| static uint64_t guest_test_virt_mem = DEFAULT_GUEST_TEST_MEM; |
| |
| /* |
| * Continuously write to the first 8 bytes of a random pages within |
| * the testing memory region. |
| */ |
| static void guest_code(void) |
| { |
| int i; |
| |
| while (true) { |
| for (i = 0; i < TEST_PAGES_PER_LOOP; i++) { |
| uint64_t addr = guest_test_virt_mem; |
| addr += (READ_ONCE(random_array[i]) % guest_num_pages) |
| * guest_page_size; |
| addr &= ~(host_page_size - 1); |
| *(uint64_t *)addr = READ_ONCE(iteration); |
| } |
| |
| /* Tell the host that we need more random numbers */ |
| GUEST_SYNC(1); |
| } |
| } |
| |
| /* Host variables */ |
| static bool host_quit; |
| |
| /* Points to the test VM memory region on which we track dirty logs */ |
| static void *host_test_mem; |
| static uint64_t host_num_pages; |
| |
| /* For statistics only */ |
| static uint64_t host_dirty_count; |
| static uint64_t host_clear_count; |
| static uint64_t host_track_next_count; |
| |
| /* |
| * We use this bitmap to track some pages that should have its dirty |
| * bit set in the _next_ iteration. For example, if we detected the |
| * page value changed to current iteration but at the same time the |
| * page bit is cleared in the latest bitmap, then the system must |
| * report that write in the next get dirty log call. |
| */ |
| static unsigned long *host_bmap_track; |
| |
| static void generate_random_array(uint64_t *guest_array, uint64_t size) |
| { |
| uint64_t i; |
| |
| for (i = 0; i < size; i++) |
| guest_array[i] = random(); |
| } |
| |
| static void *vcpu_worker(void *data) |
| { |
| int ret; |
| struct kvm_vm *vm = data; |
| uint64_t *guest_array; |
| uint64_t pages_count = 0; |
| struct kvm_run *run; |
| struct ucall uc; |
| |
| run = vcpu_state(vm, VCPU_ID); |
| |
| guest_array = addr_gva2hva(vm, (vm_vaddr_t)random_array); |
| generate_random_array(guest_array, TEST_PAGES_PER_LOOP); |
| |
| while (!READ_ONCE(host_quit)) { |
| /* Let the guest dirty the random pages */ |
| ret = _vcpu_run(vm, VCPU_ID); |
| if (get_ucall(vm, VCPU_ID, &uc) == UCALL_SYNC) { |
| pages_count += TEST_PAGES_PER_LOOP; |
| generate_random_array(guest_array, TEST_PAGES_PER_LOOP); |
| } else { |
| TEST_ASSERT(false, |
| "Invalid guest sync status: " |
| "exit_reason=%s\n", |
| exit_reason_str(run->exit_reason)); |
| } |
| } |
| |
| DEBUG("Dirtied %"PRIu64" pages\n", pages_count); |
| |
| return NULL; |
| } |
| |
| static void vm_dirty_log_verify(unsigned long *bmap) |
| { |
| uint64_t page; |
| uint64_t *value_ptr; |
| uint64_t step = host_page_size >= guest_page_size ? 1 : |
| guest_page_size / host_page_size; |
| |
| for (page = 0; page < host_num_pages; page += step) { |
| value_ptr = host_test_mem + page * host_page_size; |
| |
| /* If this is a special page that we were tracking... */ |
| if (test_and_clear_bit(page, host_bmap_track)) { |
| host_track_next_count++; |
| TEST_ASSERT(test_bit(page, bmap), |
| "Page %"PRIu64" should have its dirty bit " |
| "set in this iteration but it is missing", |
| page); |
| } |
| |
| if (test_bit(page, bmap)) { |
| host_dirty_count++; |
| /* |
| * If the bit is set, the value written onto |
| * the corresponding page should be either the |
| * previous iteration number or the current one. |
| */ |
| TEST_ASSERT(*value_ptr == iteration || |
| *value_ptr == iteration - 1, |
| "Set page %"PRIu64" value %"PRIu64 |
| " incorrect (iteration=%"PRIu64")", |
| page, *value_ptr, iteration); |
| } else { |
| host_clear_count++; |
| /* |
| * If cleared, the value written can be any |
| * value smaller or equals to the iteration |
| * number. Note that the value can be exactly |
| * (iteration-1) if that write can happen |
| * like this: |
| * |
| * (1) increase loop count to "iteration-1" |
| * (2) write to page P happens (with value |
| * "iteration-1") |
| * (3) get dirty log for "iteration-1"; we'll |
| * see that page P bit is set (dirtied), |
| * and not set the bit in host_bmap_track |
| * (4) increase loop count to "iteration" |
| * (which is current iteration) |
| * (5) get dirty log for current iteration, |
| * we'll see that page P is cleared, with |
| * value "iteration-1". |
| */ |
| TEST_ASSERT(*value_ptr <= iteration, |
| "Clear page %"PRIu64" value %"PRIu64 |
| " incorrect (iteration=%"PRIu64")", |
| page, *value_ptr, iteration); |
| if (*value_ptr == iteration) { |
| /* |
| * This page is _just_ modified; it |
| * should report its dirtyness in the |
| * next run |
| */ |
| set_bit(page, host_bmap_track); |
| } |
| } |
| } |
| } |
| |
| static struct kvm_vm *create_vm(enum vm_guest_mode mode, uint32_t vcpuid, |
| uint64_t extra_mem_pages, void *guest_code, |
| unsigned long type) |
| { |
| struct kvm_vm *vm; |
| uint64_t extra_pg_pages = extra_mem_pages / 512 * 2; |
| |
| vm = _vm_create(mode, DEFAULT_GUEST_PHY_PAGES + extra_pg_pages, |
| O_RDWR, type); |
| kvm_vm_elf_load(vm, program_invocation_name, 0, 0); |
| #ifdef __x86_64__ |
| vm_create_irqchip(vm); |
| #endif |
| vm_vcpu_add_default(vm, vcpuid, guest_code); |
| return vm; |
| } |
| |
| static void run_test(enum vm_guest_mode mode, unsigned long iterations, |
| unsigned long interval, uint64_t phys_offset) |
| { |
| unsigned int guest_pa_bits, guest_page_shift; |
| pthread_t vcpu_thread; |
| struct kvm_vm *vm; |
| uint64_t max_gfn; |
| unsigned long *bmap; |
| unsigned long type = 0; |
| |
| switch (mode) { |
| case VM_MODE_P52V48_4K: |
| guest_pa_bits = 52; |
| guest_page_shift = 12; |
| break; |
| case VM_MODE_P52V48_64K: |
| guest_pa_bits = 52; |
| guest_page_shift = 16; |
| break; |
| case VM_MODE_P48V48_4K: |
| guest_pa_bits = 48; |
| guest_page_shift = 12; |
| break; |
| case VM_MODE_P48V48_64K: |
| guest_pa_bits = 48; |
| guest_page_shift = 16; |
| break; |
| case VM_MODE_P40V48_4K: |
| guest_pa_bits = 40; |
| guest_page_shift = 12; |
| break; |
| case VM_MODE_P40V48_64K: |
| guest_pa_bits = 40; |
| guest_page_shift = 16; |
| break; |
| default: |
| TEST_ASSERT(false, "Unknown guest mode, mode: 0x%x", mode); |
| } |
| |
| DEBUG("Testing guest mode: %s\n", vm_guest_mode_string(mode)); |
| |
| #ifdef __x86_64__ |
| /* |
| * FIXME |
| * The x86_64 kvm selftests framework currently only supports a |
| * single PML4 which restricts the number of physical address |
| * bits we can change to 39. |
| */ |
| guest_pa_bits = 39; |
| #endif |
| #ifdef __aarch64__ |
| if (guest_pa_bits != 40) |
| type = KVM_VM_TYPE_ARM_IPA_SIZE(guest_pa_bits); |
| #endif |
| max_gfn = (1ul << (guest_pa_bits - guest_page_shift)) - 1; |
| guest_page_size = (1ul << guest_page_shift); |
| /* 1G of guest page sized pages */ |
| guest_num_pages = (1ul << (30 - guest_page_shift)) + 3; |
| host_page_size = getpagesize(); |
| host_num_pages = (guest_num_pages * guest_page_size) / host_page_size + |
| !!((guest_num_pages * guest_page_size) % host_page_size); |
| |
| if (!phys_offset) { |
| guest_test_phys_mem = (max_gfn - guest_num_pages) * guest_page_size; |
| guest_test_phys_mem &= ~(host_page_size - 1); |
| } else { |
| guest_test_phys_mem = phys_offset; |
| } |
| |
| DEBUG("guest physical test memory offset: 0x%lx\n", guest_test_phys_mem); |
| |
| bmap = bitmap_alloc(host_num_pages); |
| host_bmap_track = bitmap_alloc(host_num_pages); |
| |
| vm = create_vm(mode, VCPU_ID, guest_num_pages, guest_code, type); |
| |
| #ifdef USE_CLEAR_DIRTY_LOG |
| struct kvm_enable_cap cap = {}; |
| |
| cap.cap = KVM_CAP_MANUAL_DIRTY_LOG_PROTECT; |
| cap.args[0] = 1; |
| vm_enable_cap(vm, &cap); |
| #endif |
| |
| /* Add an extra memory slot for testing dirty logging */ |
| vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, |
| guest_test_phys_mem, |
| TEST_MEM_SLOT_INDEX, |
| guest_num_pages, |
| KVM_MEM_LOG_DIRTY_PAGES); |
| |
| /* Do mapping for the dirty track memory slot */ |
| virt_map(vm, guest_test_virt_mem, guest_test_phys_mem, |
| guest_num_pages * guest_page_size, 0); |
| |
| /* Cache the HVA pointer of the region */ |
| host_test_mem = addr_gpa2hva(vm, (vm_paddr_t)guest_test_phys_mem); |
| |
| #ifdef __x86_64__ |
| vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid()); |
| #endif |
| #ifdef __aarch64__ |
| ucall_init(vm, UCALL_MMIO, NULL); |
| #endif |
| |
| /* Export the shared variables to the guest */ |
| sync_global_to_guest(vm, host_page_size); |
| sync_global_to_guest(vm, guest_page_size); |
| sync_global_to_guest(vm, guest_test_virt_mem); |
| sync_global_to_guest(vm, guest_num_pages); |
| |
| /* Start the iterations */ |
| iteration = 1; |
| sync_global_to_guest(vm, iteration); |
| host_quit = false; |
| host_dirty_count = 0; |
| host_clear_count = 0; |
| host_track_next_count = 0; |
| |
| pthread_create(&vcpu_thread, NULL, vcpu_worker, vm); |
| |
| while (iteration < iterations) { |
| /* Give the vcpu thread some time to dirty some pages */ |
| usleep(interval * 1000); |
| kvm_vm_get_dirty_log(vm, TEST_MEM_SLOT_INDEX, bmap); |
| #ifdef USE_CLEAR_DIRTY_LOG |
| kvm_vm_clear_dirty_log(vm, TEST_MEM_SLOT_INDEX, bmap, 0, |
| host_num_pages); |
| #endif |
| vm_dirty_log_verify(bmap); |
| iteration++; |
| sync_global_to_guest(vm, iteration); |
| } |
| |
| /* Tell the vcpu thread to quit */ |
| host_quit = true; |
| pthread_join(vcpu_thread, NULL); |
| |
| DEBUG("Total bits checked: dirty (%"PRIu64"), clear (%"PRIu64"), " |
| "track_next (%"PRIu64")\n", host_dirty_count, host_clear_count, |
| host_track_next_count); |
| |
| free(bmap); |
| free(host_bmap_track); |
| ucall_uninit(vm); |
| kvm_vm_free(vm); |
| } |
| |
| struct vm_guest_mode_params { |
| bool supported; |
| bool enabled; |
| }; |
| struct vm_guest_mode_params vm_guest_mode_params[NUM_VM_MODES]; |
| |
| #define vm_guest_mode_params_init(mode, supported, enabled) \ |
| ({ \ |
| vm_guest_mode_params[mode] = (struct vm_guest_mode_params){ supported, enabled }; \ |
| }) |
| |
| static void help(char *name) |
| { |
| int i; |
| |
| puts(""); |
| printf("usage: %s [-h] [-i iterations] [-I interval] " |
| "[-p offset] [-m mode]\n", name); |
| puts(""); |
| printf(" -i: specify iteration counts (default: %"PRIu64")\n", |
| TEST_HOST_LOOP_N); |
| printf(" -I: specify interval in ms (default: %"PRIu64" ms)\n", |
| TEST_HOST_LOOP_INTERVAL); |
| printf(" -p: specify guest physical test memory offset\n" |
| " Warning: a low offset can conflict with the loaded test code.\n"); |
| printf(" -m: specify the guest mode ID to test " |
| "(default: test all supported modes)\n" |
| " This option may be used multiple times.\n" |
| " Guest mode IDs:\n"); |
| for (i = 0; i < NUM_VM_MODES; ++i) { |
| printf(" %d: %s%s\n", i, vm_guest_mode_string(i), |
| vm_guest_mode_params[i].supported ? " (supported)" : ""); |
| } |
| puts(""); |
| exit(0); |
| } |
| |
| int main(int argc, char *argv[]) |
| { |
| unsigned long iterations = TEST_HOST_LOOP_N; |
| unsigned long interval = TEST_HOST_LOOP_INTERVAL; |
| bool mode_selected = false; |
| uint64_t phys_offset = 0; |
| unsigned int mode, host_ipa_limit; |
| int opt, i; |
| |
| #ifdef USE_CLEAR_DIRTY_LOG |
| if (!kvm_check_cap(KVM_CAP_MANUAL_DIRTY_LOG_PROTECT)) { |
| fprintf(stderr, "KVM_CLEAR_DIRTY_LOG not available, skipping tests\n"); |
| exit(KSFT_SKIP); |
| } |
| #endif |
| |
| #ifdef __x86_64__ |
| vm_guest_mode_params_init(VM_MODE_P52V48_4K, true, true); |
| #endif |
| #ifdef __aarch64__ |
| vm_guest_mode_params_init(VM_MODE_P40V48_4K, true, true); |
| vm_guest_mode_params_init(VM_MODE_P40V48_64K, true, true); |
| |
| host_ipa_limit = kvm_check_cap(KVM_CAP_ARM_VM_IPA_SIZE); |
| if (host_ipa_limit >= 52) |
| vm_guest_mode_params_init(VM_MODE_P52V48_64K, true, true); |
| if (host_ipa_limit >= 48) { |
| vm_guest_mode_params_init(VM_MODE_P48V48_4K, true, true); |
| vm_guest_mode_params_init(VM_MODE_P48V48_64K, true, true); |
| } |
| #endif |
| |
| while ((opt = getopt(argc, argv, "hi:I:p:m:")) != -1) { |
| switch (opt) { |
| case 'i': |
| iterations = strtol(optarg, NULL, 10); |
| break; |
| case 'I': |
| interval = strtol(optarg, NULL, 10); |
| break; |
| case 'p': |
| phys_offset = strtoull(optarg, NULL, 0); |
| break; |
| case 'm': |
| if (!mode_selected) { |
| for (i = 0; i < NUM_VM_MODES; ++i) |
| vm_guest_mode_params[i].enabled = false; |
| mode_selected = true; |
| } |
| mode = strtoul(optarg, NULL, 10); |
| TEST_ASSERT(mode < NUM_VM_MODES, |
| "Guest mode ID %d too big", mode); |
| vm_guest_mode_params[mode].enabled = true; |
| break; |
| case 'h': |
| default: |
| help(argv[0]); |
| break; |
| } |
| } |
| |
| TEST_ASSERT(iterations > 2, "Iterations must be greater than two"); |
| TEST_ASSERT(interval > 0, "Interval must be greater than zero"); |
| |
| DEBUG("Test iterations: %"PRIu64", interval: %"PRIu64" (ms)\n", |
| iterations, interval); |
| |
| srandom(time(0)); |
| |
| for (i = 0; i < NUM_VM_MODES; ++i) { |
| if (!vm_guest_mode_params[i].enabled) |
| continue; |
| TEST_ASSERT(vm_guest_mode_params[i].supported, |
| "Guest mode ID %d (%s) not supported.", |
| i, vm_guest_mode_string(i)); |
| run_test(i, iterations, interval, phys_offset); |
| } |
| |
| return 0; |
| } |