tools: rename bitmap_alloc() to bitmap_zalloc()
[linux-2.6-microblaze.git] / tools / testing / selftests / kvm / dirty_log_test.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * KVM dirty page logging test
4  *
5  * Copyright (C) 2018, Red Hat, Inc.
6  */
7
8 #define _GNU_SOURCE /* for program_invocation_name */
9
10 #include <stdio.h>
11 #include <stdlib.h>
12 #include <pthread.h>
13 #include <semaphore.h>
14 #include <sys/types.h>
15 #include <signal.h>
16 #include <errno.h>
17 #include <linux/bitmap.h>
18 #include <linux/bitops.h>
19 #include <linux/atomic.h>
20
21 #include "kvm_util.h"
22 #include "test_util.h"
23 #include "guest_modes.h"
24 #include "processor.h"
25
26 #define VCPU_ID                         1
27
28 /* The memory slot index to track dirty pages */
29 #define TEST_MEM_SLOT_INDEX             1
30
31 /* Default guest test virtual memory offset */
32 #define DEFAULT_GUEST_TEST_MEM          0xc0000000
33
34 /* How many pages to dirty for each guest loop */
35 #define TEST_PAGES_PER_LOOP             1024
36
37 /* How many host loops to run (one KVM_GET_DIRTY_LOG for each loop) */
38 #define TEST_HOST_LOOP_N                32UL
39
40 /* Interval for each host loop (ms) */
41 #define TEST_HOST_LOOP_INTERVAL         10UL
42
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 #else
57 # define test_bit_le            test_bit
58 # define set_bit_le             set_bit
59 # define clear_bit_le           clear_bit
60 # define test_and_set_bit_le    test_and_set_bit
61 # define test_and_clear_bit_le  test_and_clear_bit
62 #endif
63
64 #define TEST_DIRTY_RING_COUNT           65536
65
66 #define SIG_IPI SIGUSR1
67
68 /*
69  * Guest/Host shared variables. Ensure addr_gva2hva() and/or
70  * sync_global_to/from_guest() are used when accessing from
71  * the host. READ/WRITE_ONCE() should also be used with anything
72  * that may change.
73  */
74 static uint64_t host_page_size;
75 static uint64_t guest_page_size;
76 static uint64_t guest_num_pages;
77 static uint64_t random_array[TEST_PAGES_PER_LOOP];
78 static uint64_t iteration;
79
80 /*
81  * Guest physical memory offset of the testing memory slot.
82  * This will be set to the topmost valid physical address minus
83  * the test memory size.
84  */
85 static uint64_t guest_test_phys_mem;
86
87 /*
88  * Guest virtual memory offset of the testing memory slot.
89  * Must not conflict with identity mapped test code.
90  */
91 static uint64_t guest_test_virt_mem = DEFAULT_GUEST_TEST_MEM;
92
93 /*
94  * Continuously write to the first 8 bytes of a random pages within
95  * the testing memory region.
96  */
97 static void guest_code(void)
98 {
99         uint64_t addr;
100         int i;
101
102         /*
103          * On s390x, all pages of a 1M segment are initially marked as dirty
104          * when a page of the segment is written to for the very first time.
105          * To compensate this specialty in this test, we need to touch all
106          * pages during the first iteration.
107          */
108         for (i = 0; i < guest_num_pages; i++) {
109                 addr = guest_test_virt_mem + i * guest_page_size;
110                 *(uint64_t *)addr = READ_ONCE(iteration);
111         }
112
113         while (true) {
114                 for (i = 0; i < TEST_PAGES_PER_LOOP; i++) {
115                         addr = guest_test_virt_mem;
116                         addr += (READ_ONCE(random_array[i]) % guest_num_pages)
117                                 * guest_page_size;
118                         addr &= ~(host_page_size - 1);
119                         *(uint64_t *)addr = READ_ONCE(iteration);
120                 }
121
122                 /* Tell the host that we need more random numbers */
123                 GUEST_SYNC(1);
124         }
125 }
126
127 /* Host variables */
128 static bool host_quit;
129
130 /* Points to the test VM memory region on which we track dirty logs */
131 static void *host_test_mem;
132 static uint64_t host_num_pages;
133
134 /* For statistics only */
135 static uint64_t host_dirty_count;
136 static uint64_t host_clear_count;
137 static uint64_t host_track_next_count;
138
139 /* Whether dirty ring reset is requested, or finished */
140 static sem_t sem_vcpu_stop;
141 static sem_t sem_vcpu_cont;
142 /*
143  * This is only set by main thread, and only cleared by vcpu thread.  It is
144  * used to request vcpu thread to stop at the next GUEST_SYNC, since GUEST_SYNC
145  * is the only place that we'll guarantee both "dirty bit" and "dirty data"
146  * will match.  E.g., SIG_IPI won't guarantee that if the vcpu is interrupted
147  * after setting dirty bit but before the data is written.
148  */
149 static atomic_t vcpu_sync_stop_requested;
150 /*
151  * This is updated by the vcpu thread to tell the host whether it's a
152  * ring-full event.  It should only be read until a sem_wait() of
153  * sem_vcpu_stop and before vcpu continues to run.
154  */
155 static bool dirty_ring_vcpu_ring_full;
156 /*
157  * This is only used for verifying the dirty pages.  Dirty ring has a very
158  * tricky case when the ring just got full, kvm will do userspace exit due to
159  * ring full.  When that happens, the very last PFN is set but actually the
160  * data is not changed (the guest WRITE is not really applied yet), because
161  * we found that the dirty ring is full, refused to continue the vcpu, and
162  * recorded the dirty gfn with the old contents.
163  *
164  * For this specific case, it's safe to skip checking this pfn for this
165  * bit, because it's a redundant bit, and when the write happens later the bit
166  * will be set again.  We use this variable to always keep track of the latest
167  * dirty gfn we've collected, so that if a mismatch of data found later in the
168  * verifying process, we let it pass.
169  */
170 static uint64_t dirty_ring_last_page;
171
172 enum log_mode_t {
173         /* Only use KVM_GET_DIRTY_LOG for logging */
174         LOG_MODE_DIRTY_LOG = 0,
175
176         /* Use both KVM_[GET|CLEAR]_DIRTY_LOG for logging */
177         LOG_MODE_CLEAR_LOG = 1,
178
179         /* Use dirty ring for logging */
180         LOG_MODE_DIRTY_RING = 2,
181
182         LOG_MODE_NUM,
183
184         /* Run all supported modes */
185         LOG_MODE_ALL = LOG_MODE_NUM,
186 };
187
188 /* Mode of logging to test.  Default is to run all supported modes */
189 static enum log_mode_t host_log_mode_option = LOG_MODE_ALL;
190 /* Logging mode for current run */
191 static enum log_mode_t host_log_mode;
192 static pthread_t vcpu_thread;
193 static uint32_t test_dirty_ring_count = TEST_DIRTY_RING_COUNT;
194
195 static void vcpu_kick(void)
196 {
197         pthread_kill(vcpu_thread, SIG_IPI);
198 }
199
200 /*
201  * In our test we do signal tricks, let's use a better version of
202  * sem_wait to avoid signal interrupts
203  */
204 static void sem_wait_until(sem_t *sem)
205 {
206         int ret;
207
208         do
209                 ret = sem_wait(sem);
210         while (ret == -1 && errno == EINTR);
211 }
212
213 static bool clear_log_supported(void)
214 {
215         return kvm_check_cap(KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2);
216 }
217
218 static void clear_log_create_vm_done(struct kvm_vm *vm)
219 {
220         struct kvm_enable_cap cap = {};
221         u64 manual_caps;
222
223         manual_caps = kvm_check_cap(KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2);
224         TEST_ASSERT(manual_caps, "MANUAL_CAPS is zero!");
225         manual_caps &= (KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE |
226                         KVM_DIRTY_LOG_INITIALLY_SET);
227         cap.cap = KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2;
228         cap.args[0] = manual_caps;
229         vm_enable_cap(vm, &cap);
230 }
231
232 static void dirty_log_collect_dirty_pages(struct kvm_vm *vm, int slot,
233                                           void *bitmap, uint32_t num_pages)
234 {
235         kvm_vm_get_dirty_log(vm, slot, bitmap);
236 }
237
238 static void clear_log_collect_dirty_pages(struct kvm_vm *vm, int slot,
239                                           void *bitmap, uint32_t num_pages)
240 {
241         kvm_vm_get_dirty_log(vm, slot, bitmap);
242         kvm_vm_clear_dirty_log(vm, slot, bitmap, 0, num_pages);
243 }
244
245 /* Should only be called after a GUEST_SYNC */
246 static void vcpu_handle_sync_stop(void)
247 {
248         if (atomic_read(&vcpu_sync_stop_requested)) {
249                 /* It means main thread is sleeping waiting */
250                 atomic_set(&vcpu_sync_stop_requested, false);
251                 sem_post(&sem_vcpu_stop);
252                 sem_wait_until(&sem_vcpu_cont);
253         }
254 }
255
256 static void default_after_vcpu_run(struct kvm_vm *vm, int ret, int err)
257 {
258         struct kvm_run *run = vcpu_state(vm, VCPU_ID);
259
260         TEST_ASSERT(ret == 0 || (ret == -1 && err == EINTR),
261                     "vcpu run failed: errno=%d", err);
262
263         TEST_ASSERT(get_ucall(vm, VCPU_ID, NULL) == UCALL_SYNC,
264                     "Invalid guest sync status: exit_reason=%s\n",
265                     exit_reason_str(run->exit_reason));
266
267         vcpu_handle_sync_stop();
268 }
269
270 static bool dirty_ring_supported(void)
271 {
272         return kvm_check_cap(KVM_CAP_DIRTY_LOG_RING);
273 }
274
275 static void dirty_ring_create_vm_done(struct kvm_vm *vm)
276 {
277         /*
278          * Switch to dirty ring mode after VM creation but before any
279          * of the vcpu creation.
280          */
281         vm_enable_dirty_ring(vm, test_dirty_ring_count *
282                              sizeof(struct kvm_dirty_gfn));
283 }
284
285 static inline bool dirty_gfn_is_dirtied(struct kvm_dirty_gfn *gfn)
286 {
287         return gfn->flags == KVM_DIRTY_GFN_F_DIRTY;
288 }
289
290 static inline void dirty_gfn_set_collected(struct kvm_dirty_gfn *gfn)
291 {
292         gfn->flags = KVM_DIRTY_GFN_F_RESET;
293 }
294
295 static uint32_t dirty_ring_collect_one(struct kvm_dirty_gfn *dirty_gfns,
296                                        int slot, void *bitmap,
297                                        uint32_t num_pages, uint32_t *fetch_index)
298 {
299         struct kvm_dirty_gfn *cur;
300         uint32_t count = 0;
301
302         while (true) {
303                 cur = &dirty_gfns[*fetch_index % test_dirty_ring_count];
304                 if (!dirty_gfn_is_dirtied(cur))
305                         break;
306                 TEST_ASSERT(cur->slot == slot, "Slot number didn't match: "
307                             "%u != %u", cur->slot, slot);
308                 TEST_ASSERT(cur->offset < num_pages, "Offset overflow: "
309                             "0x%llx >= 0x%x", cur->offset, num_pages);
310                 //pr_info("fetch 0x%x page %llu\n", *fetch_index, cur->offset);
311                 set_bit_le(cur->offset, bitmap);
312                 dirty_ring_last_page = cur->offset;
313                 dirty_gfn_set_collected(cur);
314                 (*fetch_index)++;
315                 count++;
316         }
317
318         return count;
319 }
320
321 static void dirty_ring_wait_vcpu(void)
322 {
323         /* This makes sure that hardware PML cache flushed */
324         vcpu_kick();
325         sem_wait_until(&sem_vcpu_stop);
326 }
327
328 static void dirty_ring_continue_vcpu(void)
329 {
330         pr_info("Notifying vcpu to continue\n");
331         sem_post(&sem_vcpu_cont);
332 }
333
334 static void dirty_ring_collect_dirty_pages(struct kvm_vm *vm, int slot,
335                                            void *bitmap, uint32_t num_pages)
336 {
337         /* We only have one vcpu */
338         static uint32_t fetch_index = 0;
339         uint32_t count = 0, cleared;
340         bool continued_vcpu = false;
341
342         dirty_ring_wait_vcpu();
343
344         if (!dirty_ring_vcpu_ring_full) {
345                 /*
346                  * This is not a ring-full event, it's safe to allow
347                  * vcpu to continue
348                  */
349                 dirty_ring_continue_vcpu();
350                 continued_vcpu = true;
351         }
352
353         /* Only have one vcpu */
354         count = dirty_ring_collect_one(vcpu_map_dirty_ring(vm, VCPU_ID),
355                                        slot, bitmap, num_pages, &fetch_index);
356
357         cleared = kvm_vm_reset_dirty_ring(vm);
358
359         /* Cleared pages should be the same as collected */
360         TEST_ASSERT(cleared == count, "Reset dirty pages (%u) mismatch "
361                     "with collected (%u)", cleared, count);
362
363         if (!continued_vcpu) {
364                 TEST_ASSERT(dirty_ring_vcpu_ring_full,
365                             "Didn't continue vcpu even without ring full");
366                 dirty_ring_continue_vcpu();
367         }
368
369         pr_info("Iteration %ld collected %u pages\n", iteration, count);
370 }
371
372 static void dirty_ring_after_vcpu_run(struct kvm_vm *vm, int ret, int err)
373 {
374         struct kvm_run *run = vcpu_state(vm, VCPU_ID);
375
376         /* A ucall-sync or ring-full event is allowed */
377         if (get_ucall(vm, VCPU_ID, NULL) == UCALL_SYNC) {
378                 /* We should allow this to continue */
379                 ;
380         } else if (run->exit_reason == KVM_EXIT_DIRTY_RING_FULL ||
381                    (ret == -1 && err == EINTR)) {
382                 /* Update the flag first before pause */
383                 WRITE_ONCE(dirty_ring_vcpu_ring_full,
384                            run->exit_reason == KVM_EXIT_DIRTY_RING_FULL);
385                 sem_post(&sem_vcpu_stop);
386                 pr_info("vcpu stops because %s...\n",
387                         dirty_ring_vcpu_ring_full ?
388                         "dirty ring is full" : "vcpu is kicked out");
389                 sem_wait_until(&sem_vcpu_cont);
390                 pr_info("vcpu continues now.\n");
391         } else {
392                 TEST_ASSERT(false, "Invalid guest sync status: "
393                             "exit_reason=%s\n",
394                             exit_reason_str(run->exit_reason));
395         }
396 }
397
398 static void dirty_ring_before_vcpu_join(void)
399 {
400         /* Kick another round of vcpu just to make sure it will quit */
401         sem_post(&sem_vcpu_cont);
402 }
403
404 struct log_mode {
405         const char *name;
406         /* Return true if this mode is supported, otherwise false */
407         bool (*supported)(void);
408         /* Hook when the vm creation is done (before vcpu creation) */
409         void (*create_vm_done)(struct kvm_vm *vm);
410         /* Hook to collect the dirty pages into the bitmap provided */
411         void (*collect_dirty_pages) (struct kvm_vm *vm, int slot,
412                                      void *bitmap, uint32_t num_pages);
413         /* Hook to call when after each vcpu run */
414         void (*after_vcpu_run)(struct kvm_vm *vm, int ret, int err);
415         void (*before_vcpu_join) (void);
416 } log_modes[LOG_MODE_NUM] = {
417         {
418                 .name = "dirty-log",
419                 .collect_dirty_pages = dirty_log_collect_dirty_pages,
420                 .after_vcpu_run = default_after_vcpu_run,
421         },
422         {
423                 .name = "clear-log",
424                 .supported = clear_log_supported,
425                 .create_vm_done = clear_log_create_vm_done,
426                 .collect_dirty_pages = clear_log_collect_dirty_pages,
427                 .after_vcpu_run = default_after_vcpu_run,
428         },
429         {
430                 .name = "dirty-ring",
431                 .supported = dirty_ring_supported,
432                 .create_vm_done = dirty_ring_create_vm_done,
433                 .collect_dirty_pages = dirty_ring_collect_dirty_pages,
434                 .before_vcpu_join = dirty_ring_before_vcpu_join,
435                 .after_vcpu_run = dirty_ring_after_vcpu_run,
436         },
437 };
438
439 /*
440  * We use this bitmap to track some pages that should have its dirty
441  * bit set in the _next_ iteration.  For example, if we detected the
442  * page value changed to current iteration but at the same time the
443  * page bit is cleared in the latest bitmap, then the system must
444  * report that write in the next get dirty log call.
445  */
446 static unsigned long *host_bmap_track;
447
448 static void log_modes_dump(void)
449 {
450         int i;
451
452         printf("all");
453         for (i = 0; i < LOG_MODE_NUM; i++)
454                 printf(", %s", log_modes[i].name);
455         printf("\n");
456 }
457
458 static bool log_mode_supported(void)
459 {
460         struct log_mode *mode = &log_modes[host_log_mode];
461
462         if (mode->supported)
463                 return mode->supported();
464
465         return true;
466 }
467
468 static void log_mode_create_vm_done(struct kvm_vm *vm)
469 {
470         struct log_mode *mode = &log_modes[host_log_mode];
471
472         if (mode->create_vm_done)
473                 mode->create_vm_done(vm);
474 }
475
476 static void log_mode_collect_dirty_pages(struct kvm_vm *vm, int slot,
477                                          void *bitmap, uint32_t num_pages)
478 {
479         struct log_mode *mode = &log_modes[host_log_mode];
480
481         TEST_ASSERT(mode->collect_dirty_pages != NULL,
482                     "collect_dirty_pages() is required for any log mode!");
483         mode->collect_dirty_pages(vm, slot, bitmap, num_pages);
484 }
485
486 static void log_mode_after_vcpu_run(struct kvm_vm *vm, int ret, int err)
487 {
488         struct log_mode *mode = &log_modes[host_log_mode];
489
490         if (mode->after_vcpu_run)
491                 mode->after_vcpu_run(vm, ret, err);
492 }
493
494 static void log_mode_before_vcpu_join(void)
495 {
496         struct log_mode *mode = &log_modes[host_log_mode];
497
498         if (mode->before_vcpu_join)
499                 mode->before_vcpu_join();
500 }
501
502 static void generate_random_array(uint64_t *guest_array, uint64_t size)
503 {
504         uint64_t i;
505
506         for (i = 0; i < size; i++)
507                 guest_array[i] = random();
508 }
509
510 static void *vcpu_worker(void *data)
511 {
512         int ret, vcpu_fd;
513         struct kvm_vm *vm = data;
514         uint64_t *guest_array;
515         uint64_t pages_count = 0;
516         struct kvm_signal_mask *sigmask = alloca(offsetof(struct kvm_signal_mask, sigset)
517                                                  + sizeof(sigset_t));
518         sigset_t *sigset = (sigset_t *) &sigmask->sigset;
519
520         vcpu_fd = vcpu_get_fd(vm, VCPU_ID);
521
522         /*
523          * SIG_IPI is unblocked atomically while in KVM_RUN.  It causes the
524          * ioctl to return with -EINTR, but it is still pending and we need
525          * to accept it with the sigwait.
526          */
527         sigmask->len = 8;
528         pthread_sigmask(0, NULL, sigset);
529         sigdelset(sigset, SIG_IPI);
530         vcpu_ioctl(vm, VCPU_ID, KVM_SET_SIGNAL_MASK, sigmask);
531
532         sigemptyset(sigset);
533         sigaddset(sigset, SIG_IPI);
534
535         guest_array = addr_gva2hva(vm, (vm_vaddr_t)random_array);
536
537         while (!READ_ONCE(host_quit)) {
538                 /* Clear any existing kick signals */
539                 generate_random_array(guest_array, TEST_PAGES_PER_LOOP);
540                 pages_count += TEST_PAGES_PER_LOOP;
541                 /* Let the guest dirty the random pages */
542                 ret = ioctl(vcpu_fd, KVM_RUN, NULL);
543                 if (ret == -1 && errno == EINTR) {
544                         int sig = -1;
545                         sigwait(sigset, &sig);
546                         assert(sig == SIG_IPI);
547                 }
548                 log_mode_after_vcpu_run(vm, ret, errno);
549         }
550
551         pr_info("Dirtied %"PRIu64" pages\n", pages_count);
552
553         return NULL;
554 }
555
556 static void vm_dirty_log_verify(enum vm_guest_mode mode, unsigned long *bmap)
557 {
558         uint64_t step = vm_num_host_pages(mode, 1);
559         uint64_t page;
560         uint64_t *value_ptr;
561         uint64_t min_iter = 0;
562
563         for (page = 0; page < host_num_pages; page += step) {
564                 value_ptr = host_test_mem + page * host_page_size;
565
566                 /* If this is a special page that we were tracking... */
567                 if (test_and_clear_bit_le(page, host_bmap_track)) {
568                         host_track_next_count++;
569                         TEST_ASSERT(test_bit_le(page, bmap),
570                                     "Page %"PRIu64" should have its dirty bit "
571                                     "set in this iteration but it is missing",
572                                     page);
573                 }
574
575                 if (test_and_clear_bit_le(page, bmap)) {
576                         bool matched;
577
578                         host_dirty_count++;
579
580                         /*
581                          * If the bit is set, the value written onto
582                          * the corresponding page should be either the
583                          * previous iteration number or the current one.
584                          */
585                         matched = (*value_ptr == iteration ||
586                                    *value_ptr == iteration - 1);
587
588                         if (host_log_mode == LOG_MODE_DIRTY_RING && !matched) {
589                                 if (*value_ptr == iteration - 2 && min_iter <= iteration - 2) {
590                                         /*
591                                          * Short answer: this case is special
592                                          * only for dirty ring test where the
593                                          * page is the last page before a kvm
594                                          * dirty ring full in iteration N-2.
595                                          *
596                                          * Long answer: Assuming ring size R,
597                                          * one possible condition is:
598                                          *
599                                          *      main thr       vcpu thr
600                                          *      --------       --------
601                                          *    iter=1
602                                          *                   write 1 to page 0~(R-1)
603                                          *                   full, vmexit
604                                          *    collect 0~(R-1)
605                                          *    kick vcpu
606                                          *                   write 1 to (R-1)~(2R-2)
607                                          *                   full, vmexit
608                                          *    iter=2
609                                          *    collect (R-1)~(2R-2)
610                                          *    kick vcpu
611                                          *                   write 1 to (2R-2)
612                                          *                   (NOTE!!! "1" cached in cpu reg)
613                                          *                   write 2 to (2R-1)~(3R-3)
614                                          *                   full, vmexit
615                                          *    iter=3
616                                          *    collect (2R-2)~(3R-3)
617                                          *    (here if we read value on page
618                                          *     "2R-2" is 1, while iter=3!!!)
619                                          *
620                                          * This however can only happen once per iteration.
621                                          */
622                                         min_iter = iteration - 1;
623                                         continue;
624                                 } else if (page == dirty_ring_last_page) {
625                                         /*
626                                          * Please refer to comments in
627                                          * dirty_ring_last_page.
628                                          */
629                                         continue;
630                                 }
631                         }
632
633                         TEST_ASSERT(matched,
634                                     "Set page %"PRIu64" value %"PRIu64
635                                     " incorrect (iteration=%"PRIu64")",
636                                     page, *value_ptr, iteration);
637                 } else {
638                         host_clear_count++;
639                         /*
640                          * If cleared, the value written can be any
641                          * value smaller or equals to the iteration
642                          * number.  Note that the value can be exactly
643                          * (iteration-1) if that write can happen
644                          * like this:
645                          *
646                          * (1) increase loop count to "iteration-1"
647                          * (2) write to page P happens (with value
648                          *     "iteration-1")
649                          * (3) get dirty log for "iteration-1"; we'll
650                          *     see that page P bit is set (dirtied),
651                          *     and not set the bit in host_bmap_track
652                          * (4) increase loop count to "iteration"
653                          *     (which is current iteration)
654                          * (5) get dirty log for current iteration,
655                          *     we'll see that page P is cleared, with
656                          *     value "iteration-1".
657                          */
658                         TEST_ASSERT(*value_ptr <= iteration,
659                                     "Clear page %"PRIu64" value %"PRIu64
660                                     " incorrect (iteration=%"PRIu64")",
661                                     page, *value_ptr, iteration);
662                         if (*value_ptr == iteration) {
663                                 /*
664                                  * This page is _just_ modified; it
665                                  * should report its dirtyness in the
666                                  * next run
667                                  */
668                                 set_bit_le(page, host_bmap_track);
669                         }
670                 }
671         }
672 }
673
674 static struct kvm_vm *create_vm(enum vm_guest_mode mode, uint32_t vcpuid,
675                                 uint64_t extra_mem_pages, void *guest_code)
676 {
677         struct kvm_vm *vm;
678         uint64_t extra_pg_pages = extra_mem_pages / 512 * 2;
679
680         pr_info("Testing guest mode: %s\n", vm_guest_mode_string(mode));
681
682         vm = vm_create(mode, DEFAULT_GUEST_PHY_PAGES + extra_pg_pages, O_RDWR);
683         kvm_vm_elf_load(vm, program_invocation_name);
684 #ifdef __x86_64__
685         vm_create_irqchip(vm);
686 #endif
687         log_mode_create_vm_done(vm);
688         vm_vcpu_add_default(vm, vcpuid, guest_code);
689         return vm;
690 }
691
692 #define DIRTY_MEM_BITS 30 /* 1G */
693 #define PAGE_SHIFT_4K  12
694
695 struct test_params {
696         unsigned long iterations;
697         unsigned long interval;
698         uint64_t phys_offset;
699 };
700
701 static void run_test(enum vm_guest_mode mode, void *arg)
702 {
703         struct test_params *p = arg;
704         struct kvm_vm *vm;
705         unsigned long *bmap;
706
707         if (!log_mode_supported()) {
708                 print_skip("Log mode '%s' not supported",
709                            log_modes[host_log_mode].name);
710                 return;
711         }
712
713         /*
714          * We reserve page table for 2 times of extra dirty mem which
715          * will definitely cover the original (1G+) test range.  Here
716          * we do the calculation with 4K page size which is the
717          * smallest so the page number will be enough for all archs
718          * (e.g., 64K page size guest will need even less memory for
719          * page tables).
720          */
721         vm = create_vm(mode, VCPU_ID,
722                        2ul << (DIRTY_MEM_BITS - PAGE_SHIFT_4K),
723                        guest_code);
724
725         guest_page_size = vm_get_page_size(vm);
726         /*
727          * A little more than 1G of guest page sized pages.  Cover the
728          * case where the size is not aligned to 64 pages.
729          */
730         guest_num_pages = (1ul << (DIRTY_MEM_BITS -
731                                    vm_get_page_shift(vm))) + 3;
732         guest_num_pages = vm_adjust_num_guest_pages(mode, guest_num_pages);
733
734         host_page_size = getpagesize();
735         host_num_pages = vm_num_host_pages(mode, guest_num_pages);
736
737         if (!p->phys_offset) {
738                 guest_test_phys_mem = (vm_get_max_gfn(vm) -
739                                        guest_num_pages) * guest_page_size;
740                 guest_test_phys_mem &= ~(host_page_size - 1);
741         } else {
742                 guest_test_phys_mem = p->phys_offset;
743         }
744
745 #ifdef __s390x__
746         /* Align to 1M (segment size) */
747         guest_test_phys_mem &= ~((1 << 20) - 1);
748 #endif
749
750         pr_info("guest physical test memory offset: 0x%lx\n", guest_test_phys_mem);
751
752         bmap = bitmap_zalloc(host_num_pages);
753         host_bmap_track = bitmap_zalloc(host_num_pages);
754
755         /* Add an extra memory slot for testing dirty logging */
756         vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS,
757                                     guest_test_phys_mem,
758                                     TEST_MEM_SLOT_INDEX,
759                                     guest_num_pages,
760                                     KVM_MEM_LOG_DIRTY_PAGES);
761
762         /* Do mapping for the dirty track memory slot */
763         virt_map(vm, guest_test_virt_mem, guest_test_phys_mem, guest_num_pages);
764
765         /* Cache the HVA pointer of the region */
766         host_test_mem = addr_gpa2hva(vm, (vm_paddr_t)guest_test_phys_mem);
767
768         ucall_init(vm, NULL);
769
770         /* Export the shared variables to the guest */
771         sync_global_to_guest(vm, host_page_size);
772         sync_global_to_guest(vm, guest_page_size);
773         sync_global_to_guest(vm, guest_test_virt_mem);
774         sync_global_to_guest(vm, guest_num_pages);
775
776         /* Start the iterations */
777         iteration = 1;
778         sync_global_to_guest(vm, iteration);
779         host_quit = false;
780         host_dirty_count = 0;
781         host_clear_count = 0;
782         host_track_next_count = 0;
783
784         pthread_create(&vcpu_thread, NULL, vcpu_worker, vm);
785
786         while (iteration < p->iterations) {
787                 /* Give the vcpu thread some time to dirty some pages */
788                 usleep(p->interval * 1000);
789                 log_mode_collect_dirty_pages(vm, TEST_MEM_SLOT_INDEX,
790                                              bmap, host_num_pages);
791
792                 /*
793                  * See vcpu_sync_stop_requested definition for details on why
794                  * we need to stop vcpu when verify data.
795                  */
796                 atomic_set(&vcpu_sync_stop_requested, true);
797                 sem_wait_until(&sem_vcpu_stop);
798                 /*
799                  * NOTE: for dirty ring, it's possible that we didn't stop at
800                  * GUEST_SYNC but instead we stopped because ring is full;
801                  * that's okay too because ring full means we're only missing
802                  * the flush of the last page, and since we handle the last
803                  * page specially verification will succeed anyway.
804                  */
805                 assert(host_log_mode == LOG_MODE_DIRTY_RING ||
806                        atomic_read(&vcpu_sync_stop_requested) == false);
807                 vm_dirty_log_verify(mode, bmap);
808                 sem_post(&sem_vcpu_cont);
809
810                 iteration++;
811                 sync_global_to_guest(vm, iteration);
812         }
813
814         /* Tell the vcpu thread to quit */
815         host_quit = true;
816         log_mode_before_vcpu_join();
817         pthread_join(vcpu_thread, NULL);
818
819         pr_info("Total bits checked: dirty (%"PRIu64"), clear (%"PRIu64"), "
820                 "track_next (%"PRIu64")\n", host_dirty_count, host_clear_count,
821                 host_track_next_count);
822
823         free(bmap);
824         free(host_bmap_track);
825         ucall_uninit(vm);
826         kvm_vm_free(vm);
827 }
828
829 static void help(char *name)
830 {
831         puts("");
832         printf("usage: %s [-h] [-i iterations] [-I interval] "
833                "[-p offset] [-m mode]\n", name);
834         puts("");
835         printf(" -c: specify dirty ring size, in number of entries\n");
836         printf("     (only useful for dirty-ring test; default: %"PRIu32")\n",
837                TEST_DIRTY_RING_COUNT);
838         printf(" -i: specify iteration counts (default: %"PRIu64")\n",
839                TEST_HOST_LOOP_N);
840         printf(" -I: specify interval in ms (default: %"PRIu64" ms)\n",
841                TEST_HOST_LOOP_INTERVAL);
842         printf(" -p: specify guest physical test memory offset\n"
843                "     Warning: a low offset can conflict with the loaded test code.\n");
844         printf(" -M: specify the host logging mode "
845                "(default: run all log modes).  Supported modes: \n\t");
846         log_modes_dump();
847         guest_modes_help();
848         puts("");
849         exit(0);
850 }
851
852 int main(int argc, char *argv[])
853 {
854         struct test_params p = {
855                 .iterations = TEST_HOST_LOOP_N,
856                 .interval = TEST_HOST_LOOP_INTERVAL,
857         };
858         int opt, i;
859         sigset_t sigset;
860
861         sem_init(&sem_vcpu_stop, 0, 0);
862         sem_init(&sem_vcpu_cont, 0, 0);
863
864         guest_modes_append_default();
865
866         while ((opt = getopt(argc, argv, "c:hi:I:p:m:M:")) != -1) {
867                 switch (opt) {
868                 case 'c':
869                         test_dirty_ring_count = strtol(optarg, NULL, 10);
870                         break;
871                 case 'i':
872                         p.iterations = strtol(optarg, NULL, 10);
873                         break;
874                 case 'I':
875                         p.interval = strtol(optarg, NULL, 10);
876                         break;
877                 case 'p':
878                         p.phys_offset = strtoull(optarg, NULL, 0);
879                         break;
880                 case 'm':
881                         guest_modes_cmdline(optarg);
882                         break;
883                 case 'M':
884                         if (!strcmp(optarg, "all")) {
885                                 host_log_mode_option = LOG_MODE_ALL;
886                                 break;
887                         }
888                         for (i = 0; i < LOG_MODE_NUM; i++) {
889                                 if (!strcmp(optarg, log_modes[i].name)) {
890                                         pr_info("Setting log mode to: '%s'\n",
891                                                 optarg);
892                                         host_log_mode_option = i;
893                                         break;
894                                 }
895                         }
896                         if (i == LOG_MODE_NUM) {
897                                 printf("Log mode '%s' invalid. Please choose "
898                                        "from: ", optarg);
899                                 log_modes_dump();
900                                 exit(1);
901                         }
902                         break;
903                 case 'h':
904                 default:
905                         help(argv[0]);
906                         break;
907                 }
908         }
909
910         TEST_ASSERT(p.iterations > 2, "Iterations must be greater than two");
911         TEST_ASSERT(p.interval > 0, "Interval must be greater than zero");
912
913         pr_info("Test iterations: %"PRIu64", interval: %"PRIu64" (ms)\n",
914                 p.iterations, p.interval);
915
916         srandom(time(0));
917
918         /* Ensure that vCPU threads start with SIG_IPI blocked.  */
919         sigemptyset(&sigset);
920         sigaddset(&sigset, SIG_IPI);
921         pthread_sigmask(SIG_BLOCK, &sigset, NULL);
922
923         if (host_log_mode_option == LOG_MODE_ALL) {
924                 /* Run each log mode */
925                 for (i = 0; i < LOG_MODE_NUM; i++) {
926                         pr_info("Testing Log Mode '%s'\n", log_modes[i].name);
927                         host_log_mode = i;
928                         for_each_guest_mode(run_test, &p);
929                 }
930         } else {
931                 host_log_mode = host_log_mode_option;
932                 for_each_guest_mode(run_test, &p);
933         }
934
935         return 0;
936 }