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1// SPDX-License-Identifier: GPL-2.02/*3 * KVM dirty page logging test4 *5 * Copyright (C) 2018, Red Hat, Inc.6 */7#include <stdio.h>8#include <stdlib.h>9#include <pthread.h>10#include <semaphore.h>11#include <sys/types.h>12#include <signal.h>13#include <errno.h>14#include <linux/bitmap.h>15#include <linux/bitops.h>16#include <linux/atomic.h>17#include <asm/barrier.h>18 19#include "kvm_util.h"20#include "test_util.h"21#include "guest_modes.h"22#include "processor.h"23#include "ucall_common.h"24 25#define DIRTY_MEM_BITS 30 /* 1G */26#define PAGE_SHIFT_4K  1227 28/* The memory slot index to track dirty pages */29#define TEST_MEM_SLOT_INDEX		130 31/* Default guest test virtual memory offset */32#define DEFAULT_GUEST_TEST_MEM		0xc000000033 34/* How many pages to dirty for each guest loop */35#define TEST_PAGES_PER_LOOP		102436 37/* How many host loops to run (one KVM_GET_DIRTY_LOG for each loop) */38#define TEST_HOST_LOOP_N		32UL39 40/* Interval for each host loop (ms) */41#define TEST_HOST_LOOP_INTERVAL		10UL42 43/* Dirty bitmaps are always little endian, so we need to swap on big endian */44#if defined(__s390x__)45# define BITOP_LE_SWIZZLE	((BITS_PER_LONG-1) & ~0x7)46# define test_bit_le(nr, addr) \47	test_bit((nr) ^ BITOP_LE_SWIZZLE, addr)48# define __set_bit_le(nr, addr) \49	__set_bit((nr) ^ BITOP_LE_SWIZZLE, addr)50# define __clear_bit_le(nr, addr) \51	__clear_bit((nr) ^ BITOP_LE_SWIZZLE, addr)52# define __test_and_set_bit_le(nr, addr) \53	__test_and_set_bit((nr) ^ BITOP_LE_SWIZZLE, addr)54# define __test_and_clear_bit_le(nr, addr) \55	__test_and_clear_bit((nr) ^ BITOP_LE_SWIZZLE, addr)56#else57# define test_bit_le			test_bit58# define __set_bit_le			__set_bit59# define __clear_bit_le			__clear_bit60# define __test_and_set_bit_le		__test_and_set_bit61# define __test_and_clear_bit_le	__test_and_clear_bit62#endif63 64#define TEST_DIRTY_RING_COUNT		6553665 66#define SIG_IPI SIGUSR167 68/*69 * Guest/Host shared variables. Ensure addr_gva2hva() and/or70 * sync_global_to/from_guest() are used when accessing from71 * the host. READ/WRITE_ONCE() should also be used with anything72 * that may change.73 */74static uint64_t host_page_size;75static uint64_t guest_page_size;76static uint64_t guest_num_pages;77static uint64_t iteration;78 79/*80 * Guest physical memory offset of the testing memory slot.81 * This will be set to the topmost valid physical address minus82 * the test memory size.83 */84static uint64_t guest_test_phys_mem;85 86/*87 * Guest virtual memory offset of the testing memory slot.88 * Must not conflict with identity mapped test code.89 */90static uint64_t guest_test_virt_mem = DEFAULT_GUEST_TEST_MEM;91 92/*93 * Continuously write to the first 8 bytes of a random pages within94 * the testing memory region.95 */96static void guest_code(void)97{98	uint64_t addr;99	int i;100 101	/*102	 * On s390x, all pages of a 1M segment are initially marked as dirty103	 * when a page of the segment is written to for the very first time.104	 * To compensate this specialty in this test, we need to touch all105	 * pages during the first iteration.106	 */107	for (i = 0; i < guest_num_pages; i++) {108		addr = guest_test_virt_mem + i * guest_page_size;109		vcpu_arch_put_guest(*(uint64_t *)addr, READ_ONCE(iteration));110	}111 112	while (true) {113		for (i = 0; i < TEST_PAGES_PER_LOOP; i++) {114			addr = guest_test_virt_mem;115			addr += (guest_random_u64(&guest_rng) % guest_num_pages)116				* guest_page_size;117			addr = align_down(addr, host_page_size);118 119			vcpu_arch_put_guest(*(uint64_t *)addr, READ_ONCE(iteration));120		}121 122		GUEST_SYNC(1);123	}124}125 126/* Host variables */127static bool host_quit;128 129/* Points to the test VM memory region on which we track dirty logs */130static void *host_test_mem;131static uint64_t host_num_pages;132 133/* For statistics only */134static uint64_t host_dirty_count;135static uint64_t host_clear_count;136static uint64_t host_track_next_count;137 138/* Whether dirty ring reset is requested, or finished */139static sem_t sem_vcpu_stop;140static sem_t sem_vcpu_cont;141/*142 * This is only set by main thread, and only cleared by vcpu thread.  It is143 * used to request vcpu thread to stop at the next GUEST_SYNC, since GUEST_SYNC144 * is the only place that we'll guarantee both "dirty bit" and "dirty data"145 * will match.  E.g., SIG_IPI won't guarantee that if the vcpu is interrupted146 * after setting dirty bit but before the data is written.147 */148static atomic_t vcpu_sync_stop_requested;149/*150 * This is updated by the vcpu thread to tell the host whether it's a151 * ring-full event.  It should only be read until a sem_wait() of152 * sem_vcpu_stop and before vcpu continues to run.153 */154static bool dirty_ring_vcpu_ring_full;155/*156 * This is only used for verifying the dirty pages.  Dirty ring has a very157 * tricky case when the ring just got full, kvm will do userspace exit due to158 * ring full.  When that happens, the very last PFN is set but actually the159 * data is not changed (the guest WRITE is not really applied yet), because160 * we found that the dirty ring is full, refused to continue the vcpu, and161 * recorded the dirty gfn with the old contents.162 *163 * For this specific case, it's safe to skip checking this pfn for this164 * bit, because it's a redundant bit, and when the write happens later the bit165 * will be set again.  We use this variable to always keep track of the latest166 * dirty gfn we've collected, so that if a mismatch of data found later in the167 * verifying process, we let it pass.168 */169static uint64_t dirty_ring_last_page;170 171enum log_mode_t {172	/* Only use KVM_GET_DIRTY_LOG for logging */173	LOG_MODE_DIRTY_LOG = 0,174 175	/* Use both KVM_[GET|CLEAR]_DIRTY_LOG for logging */176	LOG_MODE_CLEAR_LOG = 1,177 178	/* Use dirty ring for logging */179	LOG_MODE_DIRTY_RING = 2,180 181	LOG_MODE_NUM,182 183	/* Run all supported modes */184	LOG_MODE_ALL = LOG_MODE_NUM,185};186 187/* Mode of logging to test.  Default is to run all supported modes */188static enum log_mode_t host_log_mode_option = LOG_MODE_ALL;189/* Logging mode for current run */190static enum log_mode_t host_log_mode;191static pthread_t vcpu_thread;192static uint32_t test_dirty_ring_count = TEST_DIRTY_RING_COUNT;193 194static void vcpu_kick(void)195{196	pthread_kill(vcpu_thread, SIG_IPI);197}198 199/*200 * In our test we do signal tricks, let's use a better version of201 * sem_wait to avoid signal interrupts202 */203static void sem_wait_until(sem_t *sem)204{205	int ret;206 207	do208		ret = sem_wait(sem);209	while (ret == -1 && errno == EINTR);210}211 212static bool clear_log_supported(void)213{214	return kvm_has_cap(KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2);215}216 217static void clear_log_create_vm_done(struct kvm_vm *vm)218{219	u64 manual_caps;220 221	manual_caps = kvm_check_cap(KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2);222	TEST_ASSERT(manual_caps, "MANUAL_CAPS is zero!");223	manual_caps &= (KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE |224			KVM_DIRTY_LOG_INITIALLY_SET);225	vm_enable_cap(vm, KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2, manual_caps);226}227 228static void dirty_log_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot,229					  void *bitmap, uint32_t num_pages,230					  uint32_t *unused)231{232	kvm_vm_get_dirty_log(vcpu->vm, slot, bitmap);233}234 235static void clear_log_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot,236					  void *bitmap, uint32_t num_pages,237					  uint32_t *unused)238{239	kvm_vm_get_dirty_log(vcpu->vm, slot, bitmap);240	kvm_vm_clear_dirty_log(vcpu->vm, slot, bitmap, 0, num_pages);241}242 243/* Should only be called after a GUEST_SYNC */244static void vcpu_handle_sync_stop(void)245{246	if (atomic_read(&vcpu_sync_stop_requested)) {247		/* It means main thread is sleeping waiting */248		atomic_set(&vcpu_sync_stop_requested, false);249		sem_post(&sem_vcpu_stop);250		sem_wait_until(&sem_vcpu_cont);251	}252}253 254static void default_after_vcpu_run(struct kvm_vcpu *vcpu, int ret, int err)255{256	struct kvm_run *run = vcpu->run;257 258	TEST_ASSERT(ret == 0 || (ret == -1 && err == EINTR),259		    "vcpu run failed: errno=%d", err);260 261	TEST_ASSERT(get_ucall(vcpu, NULL) == UCALL_SYNC,262		    "Invalid guest sync status: exit_reason=%s",263		    exit_reason_str(run->exit_reason));264 265	vcpu_handle_sync_stop();266}267 268static bool dirty_ring_supported(void)269{270	return (kvm_has_cap(KVM_CAP_DIRTY_LOG_RING) ||271		kvm_has_cap(KVM_CAP_DIRTY_LOG_RING_ACQ_REL));272}273 274static void dirty_ring_create_vm_done(struct kvm_vm *vm)275{276	uint64_t pages;277	uint32_t limit;278 279	/*280	 * We rely on vcpu exit due to full dirty ring state. Adjust281	 * the ring buffer size to ensure we're able to reach the282	 * full dirty ring state.283	 */284	pages = (1ul << (DIRTY_MEM_BITS - vm->page_shift)) + 3;285	pages = vm_adjust_num_guest_pages(vm->mode, pages);286	if (vm->page_size < getpagesize())287		pages = vm_num_host_pages(vm->mode, pages);288 289	limit = 1 << (31 - __builtin_clz(pages));290	test_dirty_ring_count = 1 << (31 - __builtin_clz(test_dirty_ring_count));291	test_dirty_ring_count = min(limit, test_dirty_ring_count);292	pr_info("dirty ring count: 0x%x\n", test_dirty_ring_count);293 294	/*295	 * Switch to dirty ring mode after VM creation but before any296	 * of the vcpu creation.297	 */298	vm_enable_dirty_ring(vm, test_dirty_ring_count *299			     sizeof(struct kvm_dirty_gfn));300}301 302static inline bool dirty_gfn_is_dirtied(struct kvm_dirty_gfn *gfn)303{304	return smp_load_acquire(&gfn->flags) == KVM_DIRTY_GFN_F_DIRTY;305}306 307static inline void dirty_gfn_set_collected(struct kvm_dirty_gfn *gfn)308{309	smp_store_release(&gfn->flags, KVM_DIRTY_GFN_F_RESET);310}311 312static uint32_t dirty_ring_collect_one(struct kvm_dirty_gfn *dirty_gfns,313				       int slot, void *bitmap,314				       uint32_t num_pages, uint32_t *fetch_index)315{316	struct kvm_dirty_gfn *cur;317	uint32_t count = 0;318 319	while (true) {320		cur = &dirty_gfns[*fetch_index % test_dirty_ring_count];321		if (!dirty_gfn_is_dirtied(cur))322			break;323		TEST_ASSERT(cur->slot == slot, "Slot number didn't match: "324			    "%u != %u", cur->slot, slot);325		TEST_ASSERT(cur->offset < num_pages, "Offset overflow: "326			    "0x%llx >= 0x%x", cur->offset, num_pages);327		//pr_info("fetch 0x%x page %llu\n", *fetch_index, cur->offset);328		__set_bit_le(cur->offset, bitmap);329		dirty_ring_last_page = cur->offset;330		dirty_gfn_set_collected(cur);331		(*fetch_index)++;332		count++;333	}334 335	return count;336}337 338static void dirty_ring_wait_vcpu(void)339{340	/* This makes sure that hardware PML cache flushed */341	vcpu_kick();342	sem_wait_until(&sem_vcpu_stop);343}344 345static void dirty_ring_continue_vcpu(void)346{347	pr_info("Notifying vcpu to continue\n");348	sem_post(&sem_vcpu_cont);349}350 351static void dirty_ring_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot,352					   void *bitmap, uint32_t num_pages,353					   uint32_t *ring_buf_idx)354{355	uint32_t count = 0, cleared;356	bool continued_vcpu = false;357 358	dirty_ring_wait_vcpu();359 360	if (!dirty_ring_vcpu_ring_full) {361		/*362		 * This is not a ring-full event, it's safe to allow363		 * vcpu to continue364		 */365		dirty_ring_continue_vcpu();366		continued_vcpu = true;367	}368 369	/* Only have one vcpu */370	count = dirty_ring_collect_one(vcpu_map_dirty_ring(vcpu),371				       slot, bitmap, num_pages,372				       ring_buf_idx);373 374	cleared = kvm_vm_reset_dirty_ring(vcpu->vm);375 376	/*377	 * Cleared pages should be the same as collected, as KVM is supposed to378	 * clear only the entries that have been harvested.379	 */380	TEST_ASSERT(cleared == count, "Reset dirty pages (%u) mismatch "381		    "with collected (%u)", cleared, count);382 383	if (!continued_vcpu) {384		TEST_ASSERT(dirty_ring_vcpu_ring_full,385			    "Didn't continue vcpu even without ring full");386		dirty_ring_continue_vcpu();387	}388 389	pr_info("Iteration %ld collected %u pages\n", iteration, count);390}391 392static void dirty_ring_after_vcpu_run(struct kvm_vcpu *vcpu, int ret, int err)393{394	struct kvm_run *run = vcpu->run;395 396	/* A ucall-sync or ring-full event is allowed */397	if (get_ucall(vcpu, NULL) == UCALL_SYNC) {398		/* We should allow this to continue */399		;400	} else if (run->exit_reason == KVM_EXIT_DIRTY_RING_FULL ||401		   (ret == -1 && err == EINTR)) {402		/* Update the flag first before pause */403		WRITE_ONCE(dirty_ring_vcpu_ring_full,404			   run->exit_reason == KVM_EXIT_DIRTY_RING_FULL);405		sem_post(&sem_vcpu_stop);406		pr_info("vcpu stops because %s...\n",407			dirty_ring_vcpu_ring_full ?408			"dirty ring is full" : "vcpu is kicked out");409		sem_wait_until(&sem_vcpu_cont);410		pr_info("vcpu continues now.\n");411	} else {412		TEST_ASSERT(false, "Invalid guest sync status: "413			    "exit_reason=%s",414			    exit_reason_str(run->exit_reason));415	}416}417 418struct log_mode {419	const char *name;420	/* Return true if this mode is supported, otherwise false */421	bool (*supported)(void);422	/* Hook when the vm creation is done (before vcpu creation) */423	void (*create_vm_done)(struct kvm_vm *vm);424	/* Hook to collect the dirty pages into the bitmap provided */425	void (*collect_dirty_pages) (struct kvm_vcpu *vcpu, int slot,426				     void *bitmap, uint32_t num_pages,427				     uint32_t *ring_buf_idx);428	/* Hook to call when after each vcpu run */429	void (*after_vcpu_run)(struct kvm_vcpu *vcpu, int ret, int err);430} log_modes[LOG_MODE_NUM] = {431	{432		.name = "dirty-log",433		.collect_dirty_pages = dirty_log_collect_dirty_pages,434		.after_vcpu_run = default_after_vcpu_run,435	},436	{437		.name = "clear-log",438		.supported = clear_log_supported,439		.create_vm_done = clear_log_create_vm_done,440		.collect_dirty_pages = clear_log_collect_dirty_pages,441		.after_vcpu_run = default_after_vcpu_run,442	},443	{444		.name = "dirty-ring",445		.supported = dirty_ring_supported,446		.create_vm_done = dirty_ring_create_vm_done,447		.collect_dirty_pages = dirty_ring_collect_dirty_pages,448		.after_vcpu_run = dirty_ring_after_vcpu_run,449	},450};451 452/*453 * We use this bitmap to track some pages that should have its dirty454 * bit set in the _next_ iteration.  For example, if we detected the455 * page value changed to current iteration but at the same time the456 * page bit is cleared in the latest bitmap, then the system must457 * report that write in the next get dirty log call.458 */459static unsigned long *host_bmap_track;460 461static void log_modes_dump(void)462{463	int i;464 465	printf("all");466	for (i = 0; i < LOG_MODE_NUM; i++)467		printf(", %s", log_modes[i].name);468	printf("\n");469}470 471static bool log_mode_supported(void)472{473	struct log_mode *mode = &log_modes[host_log_mode];474 475	if (mode->supported)476		return mode->supported();477 478	return true;479}480 481static void log_mode_create_vm_done(struct kvm_vm *vm)482{483	struct log_mode *mode = &log_modes[host_log_mode];484 485	if (mode->create_vm_done)486		mode->create_vm_done(vm);487}488 489static void log_mode_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot,490					 void *bitmap, uint32_t num_pages,491					 uint32_t *ring_buf_idx)492{493	struct log_mode *mode = &log_modes[host_log_mode];494 495	TEST_ASSERT(mode->collect_dirty_pages != NULL,496		    "collect_dirty_pages() is required for any log mode!");497	mode->collect_dirty_pages(vcpu, slot, bitmap, num_pages, ring_buf_idx);498}499 500static void log_mode_after_vcpu_run(struct kvm_vcpu *vcpu, int ret, int err)501{502	struct log_mode *mode = &log_modes[host_log_mode];503 504	if (mode->after_vcpu_run)505		mode->after_vcpu_run(vcpu, ret, err);506}507 508static void *vcpu_worker(void *data)509{510	int ret;511	struct kvm_vcpu *vcpu = data;512	uint64_t pages_count = 0;513	struct kvm_signal_mask *sigmask = alloca(offsetof(struct kvm_signal_mask, sigset)514						 + sizeof(sigset_t));515	sigset_t *sigset = (sigset_t *) &sigmask->sigset;516 517	/*518	 * SIG_IPI is unblocked atomically while in KVM_RUN.  It causes the519	 * ioctl to return with -EINTR, but it is still pending and we need520	 * to accept it with the sigwait.521	 */522	sigmask->len = 8;523	pthread_sigmask(0, NULL, sigset);524	sigdelset(sigset, SIG_IPI);525	vcpu_ioctl(vcpu, KVM_SET_SIGNAL_MASK, sigmask);526 527	sigemptyset(sigset);528	sigaddset(sigset, SIG_IPI);529 530	while (!READ_ONCE(host_quit)) {531		/* Clear any existing kick signals */532		pages_count += TEST_PAGES_PER_LOOP;533		/* Let the guest dirty the random pages */534		ret = __vcpu_run(vcpu);535		if (ret == -1 && errno == EINTR) {536			int sig = -1;537			sigwait(sigset, &sig);538			assert(sig == SIG_IPI);539		}540		log_mode_after_vcpu_run(vcpu, ret, errno);541	}542 543	pr_info("Dirtied %"PRIu64" pages\n", pages_count);544 545	return NULL;546}547 548static void vm_dirty_log_verify(enum vm_guest_mode mode, unsigned long *bmap)549{550	uint64_t step = vm_num_host_pages(mode, 1);551	uint64_t page;552	uint64_t *value_ptr;553	uint64_t min_iter = 0;554 555	for (page = 0; page < host_num_pages; page += step) {556		value_ptr = host_test_mem + page * host_page_size;557 558		/* If this is a special page that we were tracking... */559		if (__test_and_clear_bit_le(page, host_bmap_track)) {560			host_track_next_count++;561			TEST_ASSERT(test_bit_le(page, bmap),562				    "Page %"PRIu64" should have its dirty bit "563				    "set in this iteration but it is missing",564				    page);565		}566 567		if (__test_and_clear_bit_le(page, bmap)) {568			bool matched;569 570			host_dirty_count++;571 572			/*573			 * If the bit is set, the value written onto574			 * the corresponding page should be either the575			 * previous iteration number or the current one.576			 */577			matched = (*value_ptr == iteration ||578				   *value_ptr == iteration - 1);579 580			if (host_log_mode == LOG_MODE_DIRTY_RING && !matched) {581				if (*value_ptr == iteration - 2 && min_iter <= iteration - 2) {582					/*583					 * Short answer: this case is special584					 * only for dirty ring test where the585					 * page is the last page before a kvm586					 * dirty ring full in iteration N-2.587					 *588					 * Long answer: Assuming ring size R,589					 * one possible condition is:590					 *591					 *      main thr       vcpu thr592					 *      --------       --------593					 *    iter=1594					 *                   write 1 to page 0~(R-1)595					 *                   full, vmexit596					 *    collect 0~(R-1)597					 *    kick vcpu598					 *                   write 1 to (R-1)~(2R-2)599					 *                   full, vmexit600					 *    iter=2601					 *    collect (R-1)~(2R-2)602					 *    kick vcpu603					 *                   write 1 to (2R-2)604					 *                   (NOTE!!! "1" cached in cpu reg)605					 *                   write 2 to (2R-1)~(3R-3)606					 *                   full, vmexit607					 *    iter=3608					 *    collect (2R-2)~(3R-3)609					 *    (here if we read value on page610					 *     "2R-2" is 1, while iter=3!!!)611					 *612					 * This however can only happen once per iteration.613					 */614					min_iter = iteration - 1;615					continue;616				} else if (page == dirty_ring_last_page) {617					/*618					 * Please refer to comments in619					 * dirty_ring_last_page.620					 */621					continue;622				}623			}624 625			TEST_ASSERT(matched,626				    "Set page %"PRIu64" value %"PRIu64627				    " incorrect (iteration=%"PRIu64")",628				    page, *value_ptr, iteration);629		} else {630			host_clear_count++;631			/*632			 * If cleared, the value written can be any633			 * value smaller or equals to the iteration634			 * number.  Note that the value can be exactly635			 * (iteration-1) if that write can happen636			 * like this:637			 *638			 * (1) increase loop count to "iteration-1"639			 * (2) write to page P happens (with value640			 *     "iteration-1")641			 * (3) get dirty log for "iteration-1"; we'll642			 *     see that page P bit is set (dirtied),643			 *     and not set the bit in host_bmap_track644			 * (4) increase loop count to "iteration"645			 *     (which is current iteration)646			 * (5) get dirty log for current iteration,647			 *     we'll see that page P is cleared, with648			 *     value "iteration-1".649			 */650			TEST_ASSERT(*value_ptr <= iteration,651				    "Clear page %"PRIu64" value %"PRIu64652				    " incorrect (iteration=%"PRIu64")",653				    page, *value_ptr, iteration);654			if (*value_ptr == iteration) {655				/*656				 * This page is _just_ modified; it657				 * should report its dirtyness in the658				 * next run659				 */660				__set_bit_le(page, host_bmap_track);661			}662		}663	}664}665 666static struct kvm_vm *create_vm(enum vm_guest_mode mode, struct kvm_vcpu **vcpu,667				uint64_t extra_mem_pages, void *guest_code)668{669	struct kvm_vm *vm;670 671	pr_info("Testing guest mode: %s\n", vm_guest_mode_string(mode));672 673	vm = __vm_create(VM_SHAPE(mode), 1, extra_mem_pages);674 675	log_mode_create_vm_done(vm);676	*vcpu = vm_vcpu_add(vm, 0, guest_code);677	return vm;678}679 680struct test_params {681	unsigned long iterations;682	unsigned long interval;683	uint64_t phys_offset;684};685 686static void run_test(enum vm_guest_mode mode, void *arg)687{688	struct test_params *p = arg;689	struct kvm_vcpu *vcpu;690	struct kvm_vm *vm;691	unsigned long *bmap;692	uint32_t ring_buf_idx = 0;693	int sem_val;694 695	if (!log_mode_supported()) {696		print_skip("Log mode '%s' not supported",697			   log_modes[host_log_mode].name);698		return;699	}700 701	/*702	 * We reserve page table for 2 times of extra dirty mem which703	 * will definitely cover the original (1G+) test range.  Here704	 * we do the calculation with 4K page size which is the705	 * smallest so the page number will be enough for all archs706	 * (e.g., 64K page size guest will need even less memory for707	 * page tables).708	 */709	vm = create_vm(mode, &vcpu,710		       2ul << (DIRTY_MEM_BITS - PAGE_SHIFT_4K), guest_code);711 712	guest_page_size = vm->page_size;713	/*714	 * A little more than 1G of guest page sized pages.  Cover the715	 * case where the size is not aligned to 64 pages.716	 */717	guest_num_pages = (1ul << (DIRTY_MEM_BITS - vm->page_shift)) + 3;718	guest_num_pages = vm_adjust_num_guest_pages(mode, guest_num_pages);719 720	host_page_size = getpagesize();721	host_num_pages = vm_num_host_pages(mode, guest_num_pages);722 723	if (!p->phys_offset) {724		guest_test_phys_mem = (vm->max_gfn - guest_num_pages) *725				      guest_page_size;726		guest_test_phys_mem = align_down(guest_test_phys_mem, host_page_size);727	} else {728		guest_test_phys_mem = p->phys_offset;729	}730 731#ifdef __s390x__732	/* Align to 1M (segment size) */733	guest_test_phys_mem = align_down(guest_test_phys_mem, 1 << 20);734#endif735 736	pr_info("guest physical test memory offset: 0x%lx\n", guest_test_phys_mem);737 738	bmap = bitmap_zalloc(host_num_pages);739	host_bmap_track = bitmap_zalloc(host_num_pages);740 741	/* Add an extra memory slot for testing dirty logging */742	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,743				    guest_test_phys_mem,744				    TEST_MEM_SLOT_INDEX,745				    guest_num_pages,746				    KVM_MEM_LOG_DIRTY_PAGES);747 748	/* Do mapping for the dirty track memory slot */749	virt_map(vm, guest_test_virt_mem, guest_test_phys_mem, guest_num_pages);750 751	/* Cache the HVA pointer of the region */752	host_test_mem = addr_gpa2hva(vm, (vm_paddr_t)guest_test_phys_mem);753 754	/* Export the shared variables to the guest */755	sync_global_to_guest(vm, host_page_size);756	sync_global_to_guest(vm, guest_page_size);757	sync_global_to_guest(vm, guest_test_virt_mem);758	sync_global_to_guest(vm, guest_num_pages);759 760	/* Start the iterations */761	iteration = 1;762	sync_global_to_guest(vm, iteration);763	WRITE_ONCE(host_quit, false);764	host_dirty_count = 0;765	host_clear_count = 0;766	host_track_next_count = 0;767	WRITE_ONCE(dirty_ring_vcpu_ring_full, false);768 769	/*770	 * Ensure the previous iteration didn't leave a dangling semaphore, i.e.771	 * that the main task and vCPU worker were synchronized and completed772	 * verification of all iterations.773	 */774	sem_getvalue(&sem_vcpu_stop, &sem_val);775	TEST_ASSERT_EQ(sem_val, 0);776	sem_getvalue(&sem_vcpu_cont, &sem_val);777	TEST_ASSERT_EQ(sem_val, 0);778 779	pthread_create(&vcpu_thread, NULL, vcpu_worker, vcpu);780 781	while (iteration < p->iterations) {782		/* Give the vcpu thread some time to dirty some pages */783		usleep(p->interval * 1000);784		log_mode_collect_dirty_pages(vcpu, TEST_MEM_SLOT_INDEX,785					     bmap, host_num_pages,786					     &ring_buf_idx);787 788		/*789		 * See vcpu_sync_stop_requested definition for details on why790		 * we need to stop vcpu when verify data.791		 */792		atomic_set(&vcpu_sync_stop_requested, true);793		sem_wait_until(&sem_vcpu_stop);794		/*795		 * NOTE: for dirty ring, it's possible that we didn't stop at796		 * GUEST_SYNC but instead we stopped because ring is full;797		 * that's okay too because ring full means we're only missing798		 * the flush of the last page, and since we handle the last799		 * page specially verification will succeed anyway.800		 */801		assert(host_log_mode == LOG_MODE_DIRTY_RING ||802		       atomic_read(&vcpu_sync_stop_requested) == false);803		vm_dirty_log_verify(mode, bmap);804 805		/*806		 * Set host_quit before sem_vcpu_cont in the final iteration to807		 * ensure that the vCPU worker doesn't resume the guest.  As808		 * above, the dirty ring test may stop and wait even when not809		 * explicitly request to do so, i.e. would hang waiting for a810		 * "continue" if it's allowed to resume the guest.811		 */812		if (++iteration == p->iterations)813			WRITE_ONCE(host_quit, true);814 815		sem_post(&sem_vcpu_cont);816		sync_global_to_guest(vm, iteration);817	}818 819	pthread_join(vcpu_thread, NULL);820 821	pr_info("Total bits checked: dirty (%"PRIu64"), clear (%"PRIu64"), "822		"track_next (%"PRIu64")\n", host_dirty_count, host_clear_count,823		host_track_next_count);824 825	free(bmap);826	free(host_bmap_track);827	kvm_vm_free(vm);828}829 830static void help(char *name)831{832	puts("");833	printf("usage: %s [-h] [-i iterations] [-I interval] "834	       "[-p offset] [-m mode]\n", name);835	puts("");836	printf(" -c: hint to dirty ring size, in number of entries\n");837	printf("     (only useful for dirty-ring test; default: %"PRIu32")\n",838	       TEST_DIRTY_RING_COUNT);839	printf(" -i: specify iteration counts (default: %"PRIu64")\n",840	       TEST_HOST_LOOP_N);841	printf(" -I: specify interval in ms (default: %"PRIu64" ms)\n",842	       TEST_HOST_LOOP_INTERVAL);843	printf(" -p: specify guest physical test memory offset\n"844	       "     Warning: a low offset can conflict with the loaded test code.\n");845	printf(" -M: specify the host logging mode "846	       "(default: run all log modes).  Supported modes: \n\t");847	log_modes_dump();848	guest_modes_help();849	puts("");850	exit(0);851}852 853int main(int argc, char *argv[])854{855	struct test_params p = {856		.iterations = TEST_HOST_LOOP_N,857		.interval = TEST_HOST_LOOP_INTERVAL,858	};859	int opt, i;860	sigset_t sigset;861 862	sem_init(&sem_vcpu_stop, 0, 0);863	sem_init(&sem_vcpu_cont, 0, 0);864 865	guest_modes_append_default();866 867	while ((opt = getopt(argc, argv, "c:hi:I:p:m:M:")) != -1) {868		switch (opt) {869		case 'c':870			test_dirty_ring_count = strtol(optarg, NULL, 10);871			break;872		case 'i':873			p.iterations = strtol(optarg, NULL, 10);874			break;875		case 'I':876			p.interval = strtol(optarg, NULL, 10);877			break;878		case 'p':879			p.phys_offset = strtoull(optarg, NULL, 0);880			break;881		case 'm':882			guest_modes_cmdline(optarg);883			break;884		case 'M':885			if (!strcmp(optarg, "all")) {886				host_log_mode_option = LOG_MODE_ALL;887				break;888			}889			for (i = 0; i < LOG_MODE_NUM; i++) {890				if (!strcmp(optarg, log_modes[i].name)) {891					pr_info("Setting log mode to: '%s'\n",892						optarg);893					host_log_mode_option = i;894					break;895				}896			}897			if (i == LOG_MODE_NUM) {898				printf("Log mode '%s' invalid. Please choose "899				       "from: ", optarg);900				log_modes_dump();901				exit(1);902			}903			break;904		case 'h':905		default:906			help(argv[0]);907			break;908		}909	}910 911	TEST_ASSERT(p.iterations > 2, "Iterations must be greater than two");912	TEST_ASSERT(p.interval > 0, "Interval must be greater than zero");913 914	pr_info("Test iterations: %"PRIu64", interval: %"PRIu64" (ms)\n",915		p.iterations, p.interval);916 917	srandom(time(0));918 919	/* Ensure that vCPU threads start with SIG_IPI blocked.  */920	sigemptyset(&sigset);921	sigaddset(&sigset, SIG_IPI);922	pthread_sigmask(SIG_BLOCK, &sigset, NULL);923 924	if (host_log_mode_option == LOG_MODE_ALL) {925		/* Run each log mode */926		for (i = 0; i < LOG_MODE_NUM; i++) {927			pr_info("Testing Log Mode '%s'\n", log_modes[i].name);928			host_log_mode = i;929			for_each_guest_mode(run_test, &p);930		}931	} else {932		host_log_mode = host_log_mode_option;933		for_each_guest_mode(run_test, &p);934	}935 936	return 0;937}938