hw/arm/virt-acpi-build: don't save VirtGuestInfo on AcpiBuildState
[qemu.git] / migration / migration.c
1 /*
2 * QEMU live migration
3 *
4 * Copyright IBM, Corp. 2008
5 *
6 * Authors:
7 * Anthony Liguori <aliguori@us.ibm.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
11 *
12 * Contributions after 2012-01-13 are licensed under the terms of the
13 * GNU GPL, version 2 or (at your option) any later version.
14 */
15
16 #include "qemu/osdep.h"
17 #include "qemu/cutils.h"
18 #include "qemu/error-report.h"
19 #include "qemu/main-loop.h"
20 #include "migration/migration.h"
21 #include "migration/qemu-file.h"
22 #include "sysemu/sysemu.h"
23 #include "block/block.h"
24 #include "qapi/qmp/qerror.h"
25 #include "qapi/util.h"
26 #include "qemu/sockets.h"
27 #include "qemu/rcu.h"
28 #include "migration/block.h"
29 #include "migration/postcopy-ram.h"
30 #include "qemu/thread.h"
31 #include "qmp-commands.h"
32 #include "trace.h"
33 #include "qapi-event.h"
34 #include "qom/cpu.h"
35 #include "exec/memory.h"
36 #include "exec/address-spaces.h"
37 #include "io/channel-buffer.h"
38 #include "io/channel-tls.h"
39 #include "migration/colo.h"
40
41 #define MAX_THROTTLE (32 << 20) /* Migration transfer speed throttling */
42
43 /* Amount of time to allocate to each "chunk" of bandwidth-throttled
44 * data. */
45 #define BUFFER_DELAY 100
46 #define XFER_LIMIT_RATIO (1000 / BUFFER_DELAY)
47
48 /* Time in milliseconds we are allowed to stop the source,
49 * for sending the last part */
50 #define DEFAULT_MIGRATE_SET_DOWNTIME 300
51
52 /* Default compression thread count */
53 #define DEFAULT_MIGRATE_COMPRESS_THREAD_COUNT 8
54 /* Default decompression thread count, usually decompression is at
55 * least 4 times as fast as compression.*/
56 #define DEFAULT_MIGRATE_DECOMPRESS_THREAD_COUNT 2
57 /*0: means nocompress, 1: best speed, ... 9: best compress ratio */
58 #define DEFAULT_MIGRATE_COMPRESS_LEVEL 1
59 /* Define default autoconverge cpu throttle migration parameters */
60 #define DEFAULT_MIGRATE_CPU_THROTTLE_INITIAL 20
61 #define DEFAULT_MIGRATE_CPU_THROTTLE_INCREMENT 10
62
63 /* Migration XBZRLE default cache size */
64 #define DEFAULT_MIGRATE_CACHE_SIZE (64 * 1024 * 1024)
65
66 /* The delay time (in ms) between two COLO checkpoints
67 * Note: Please change this default value to 10000 when we support hybrid mode.
68 */
69 #define DEFAULT_MIGRATE_X_CHECKPOINT_DELAY 200
70
71 static NotifierList migration_state_notifiers =
72 NOTIFIER_LIST_INITIALIZER(migration_state_notifiers);
73
74 static bool deferred_incoming;
75
76 /*
77 * Current state of incoming postcopy; note this is not part of
78 * MigrationIncomingState since it's state is used during cleanup
79 * at the end as MIS is being freed.
80 */
81 static PostcopyState incoming_postcopy_state;
82
83 /* When we add fault tolerance, we could have several
84 migrations at once. For now we don't need to add
85 dynamic creation of migration */
86
87 /* For outgoing */
88 MigrationState *migrate_get_current(void)
89 {
90 static bool once;
91 static MigrationState current_migration = {
92 .state = MIGRATION_STATUS_NONE,
93 .xbzrle_cache_size = DEFAULT_MIGRATE_CACHE_SIZE,
94 .mbps = -1,
95 .parameters = {
96 .compress_level = DEFAULT_MIGRATE_COMPRESS_LEVEL,
97 .compress_threads = DEFAULT_MIGRATE_COMPRESS_THREAD_COUNT,
98 .decompress_threads = DEFAULT_MIGRATE_DECOMPRESS_THREAD_COUNT,
99 .cpu_throttle_initial = DEFAULT_MIGRATE_CPU_THROTTLE_INITIAL,
100 .cpu_throttle_increment = DEFAULT_MIGRATE_CPU_THROTTLE_INCREMENT,
101 .max_bandwidth = MAX_THROTTLE,
102 .downtime_limit = DEFAULT_MIGRATE_SET_DOWNTIME,
103 .x_checkpoint_delay = DEFAULT_MIGRATE_X_CHECKPOINT_DELAY,
104 },
105 };
106
107 if (!once) {
108 qemu_mutex_init(&current_migration.src_page_req_mutex);
109 once = true;
110 }
111 return &current_migration;
112 }
113
114 /* For incoming */
115 static MigrationIncomingState *mis_current;
116
117 MigrationIncomingState *migration_incoming_get_current(void)
118 {
119 return mis_current;
120 }
121
122 MigrationIncomingState *migration_incoming_state_new(QEMUFile* f)
123 {
124 mis_current = g_new0(MigrationIncomingState, 1);
125 mis_current->from_src_file = f;
126 mis_current->state = MIGRATION_STATUS_NONE;
127 QLIST_INIT(&mis_current->loadvm_handlers);
128 qemu_mutex_init(&mis_current->rp_mutex);
129 qemu_event_init(&mis_current->main_thread_load_event, false);
130
131 return mis_current;
132 }
133
134 void migration_incoming_state_destroy(void)
135 {
136 qemu_event_destroy(&mis_current->main_thread_load_event);
137 loadvm_free_handlers(mis_current);
138 g_free(mis_current);
139 mis_current = NULL;
140 }
141
142
143 typedef struct {
144 bool optional;
145 uint32_t size;
146 uint8_t runstate[100];
147 RunState state;
148 bool received;
149 } GlobalState;
150
151 static GlobalState global_state;
152
153 int global_state_store(void)
154 {
155 if (!runstate_store((char *)global_state.runstate,
156 sizeof(global_state.runstate))) {
157 error_report("runstate name too big: %s", global_state.runstate);
158 trace_migrate_state_too_big();
159 return -EINVAL;
160 }
161 return 0;
162 }
163
164 void global_state_store_running(void)
165 {
166 const char *state = RunState_lookup[RUN_STATE_RUNNING];
167 strncpy((char *)global_state.runstate,
168 state, sizeof(global_state.runstate));
169 }
170
171 static bool global_state_received(void)
172 {
173 return global_state.received;
174 }
175
176 static RunState global_state_get_runstate(void)
177 {
178 return global_state.state;
179 }
180
181 void global_state_set_optional(void)
182 {
183 global_state.optional = true;
184 }
185
186 static bool global_state_needed(void *opaque)
187 {
188 GlobalState *s = opaque;
189 char *runstate = (char *)s->runstate;
190
191 /* If it is not optional, it is mandatory */
192
193 if (s->optional == false) {
194 return true;
195 }
196
197 /* If state is running or paused, it is not needed */
198
199 if (strcmp(runstate, "running") == 0 ||
200 strcmp(runstate, "paused") == 0) {
201 return false;
202 }
203
204 /* for any other state it is needed */
205 return true;
206 }
207
208 static int global_state_post_load(void *opaque, int version_id)
209 {
210 GlobalState *s = opaque;
211 Error *local_err = NULL;
212 int r;
213 char *runstate = (char *)s->runstate;
214
215 s->received = true;
216 trace_migrate_global_state_post_load(runstate);
217
218 r = qapi_enum_parse(RunState_lookup, runstate, RUN_STATE__MAX,
219 -1, &local_err);
220
221 if (r == -1) {
222 if (local_err) {
223 error_report_err(local_err);
224 }
225 return -EINVAL;
226 }
227 s->state = r;
228
229 return 0;
230 }
231
232 static void global_state_pre_save(void *opaque)
233 {
234 GlobalState *s = opaque;
235
236 trace_migrate_global_state_pre_save((char *)s->runstate);
237 s->size = strlen((char *)s->runstate) + 1;
238 }
239
240 static const VMStateDescription vmstate_globalstate = {
241 .name = "globalstate",
242 .version_id = 1,
243 .minimum_version_id = 1,
244 .post_load = global_state_post_load,
245 .pre_save = global_state_pre_save,
246 .needed = global_state_needed,
247 .fields = (VMStateField[]) {
248 VMSTATE_UINT32(size, GlobalState),
249 VMSTATE_BUFFER(runstate, GlobalState),
250 VMSTATE_END_OF_LIST()
251 },
252 };
253
254 void register_global_state(void)
255 {
256 /* We would use it independently that we receive it */
257 strcpy((char *)&global_state.runstate, "");
258 global_state.received = false;
259 vmstate_register(NULL, 0, &vmstate_globalstate, &global_state);
260 }
261
262 static void migrate_generate_event(int new_state)
263 {
264 if (migrate_use_events()) {
265 qapi_event_send_migration(new_state, &error_abort);
266 }
267 }
268
269 /*
270 * Called on -incoming with a defer: uri.
271 * The migration can be started later after any parameters have been
272 * changed.
273 */
274 static void deferred_incoming_migration(Error **errp)
275 {
276 if (deferred_incoming) {
277 error_setg(errp, "Incoming migration already deferred");
278 }
279 deferred_incoming = true;
280 }
281
282 /* Request a range of pages from the source VM at the given
283 * start address.
284 * rbname: Name of the RAMBlock to request the page in, if NULL it's the same
285 * as the last request (a name must have been given previously)
286 * Start: Address offset within the RB
287 * Len: Length in bytes required - must be a multiple of pagesize
288 */
289 void migrate_send_rp_req_pages(MigrationIncomingState *mis, const char *rbname,
290 ram_addr_t start, size_t len)
291 {
292 uint8_t bufc[12 + 1 + 255]; /* start (8), len (4), rbname up to 256 */
293 size_t msglen = 12; /* start + len */
294
295 *(uint64_t *)bufc = cpu_to_be64((uint64_t)start);
296 *(uint32_t *)(bufc + 8) = cpu_to_be32((uint32_t)len);
297
298 if (rbname) {
299 int rbname_len = strlen(rbname);
300 assert(rbname_len < 256);
301
302 bufc[msglen++] = rbname_len;
303 memcpy(bufc + msglen, rbname, rbname_len);
304 msglen += rbname_len;
305 migrate_send_rp_message(mis, MIG_RP_MSG_REQ_PAGES_ID, msglen, bufc);
306 } else {
307 migrate_send_rp_message(mis, MIG_RP_MSG_REQ_PAGES, msglen, bufc);
308 }
309 }
310
311 void qemu_start_incoming_migration(const char *uri, Error **errp)
312 {
313 const char *p;
314
315 qapi_event_send_migration(MIGRATION_STATUS_SETUP, &error_abort);
316 if (!strcmp(uri, "defer")) {
317 deferred_incoming_migration(errp);
318 } else if (strstart(uri, "tcp:", &p)) {
319 tcp_start_incoming_migration(p, errp);
320 #ifdef CONFIG_RDMA
321 } else if (strstart(uri, "rdma:", &p)) {
322 rdma_start_incoming_migration(p, errp);
323 #endif
324 } else if (strstart(uri, "exec:", &p)) {
325 exec_start_incoming_migration(p, errp);
326 } else if (strstart(uri, "unix:", &p)) {
327 unix_start_incoming_migration(p, errp);
328 } else if (strstart(uri, "fd:", &p)) {
329 fd_start_incoming_migration(p, errp);
330 } else {
331 error_setg(errp, "unknown migration protocol: %s", uri);
332 }
333 }
334
335 static void process_incoming_migration_bh(void *opaque)
336 {
337 Error *local_err = NULL;
338 MigrationIncomingState *mis = opaque;
339
340 /* Make sure all file formats flush their mutable metadata */
341 bdrv_invalidate_cache_all(&local_err);
342 if (local_err) {
343 migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
344 MIGRATION_STATUS_FAILED);
345 error_report_err(local_err);
346 migrate_decompress_threads_join();
347 exit(EXIT_FAILURE);
348 }
349
350 /*
351 * This must happen after all error conditions are dealt with and
352 * we're sure the VM is going to be running on this host.
353 */
354 qemu_announce_self();
355
356 /* If global state section was not received or we are in running
357 state, we need to obey autostart. Any other state is set with
358 runstate_set. */
359
360 if (!global_state_received() ||
361 global_state_get_runstate() == RUN_STATE_RUNNING) {
362 if (autostart) {
363 vm_start();
364 } else {
365 runstate_set(RUN_STATE_PAUSED);
366 }
367 } else {
368 runstate_set(global_state_get_runstate());
369 }
370 migrate_decompress_threads_join();
371 /*
372 * This must happen after any state changes since as soon as an external
373 * observer sees this event they might start to prod at the VM assuming
374 * it's ready to use.
375 */
376 migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
377 MIGRATION_STATUS_COMPLETED);
378 qemu_bh_delete(mis->bh);
379 migration_incoming_state_destroy();
380 }
381
382 static void process_incoming_migration_co(void *opaque)
383 {
384 QEMUFile *f = opaque;
385 MigrationIncomingState *mis;
386 PostcopyState ps;
387 int ret;
388
389 mis = migration_incoming_state_new(f);
390 postcopy_state_set(POSTCOPY_INCOMING_NONE);
391 migrate_set_state(&mis->state, MIGRATION_STATUS_NONE,
392 MIGRATION_STATUS_ACTIVE);
393 ret = qemu_loadvm_state(f);
394
395 ps = postcopy_state_get();
396 trace_process_incoming_migration_co_end(ret, ps);
397 if (ps != POSTCOPY_INCOMING_NONE) {
398 if (ps == POSTCOPY_INCOMING_ADVISE) {
399 /*
400 * Where a migration had postcopy enabled (and thus went to advise)
401 * but managed to complete within the precopy period, we can use
402 * the normal exit.
403 */
404 postcopy_ram_incoming_cleanup(mis);
405 } else if (ret >= 0) {
406 /*
407 * Postcopy was started, cleanup should happen at the end of the
408 * postcopy thread.
409 */
410 trace_process_incoming_migration_co_postcopy_end_main();
411 return;
412 }
413 /* Else if something went wrong then just fall out of the normal exit */
414 }
415
416 /* we get COLO info, and know if we are in COLO mode */
417 if (!ret && migration_incoming_enable_colo()) {
418 mis->migration_incoming_co = qemu_coroutine_self();
419 qemu_thread_create(&mis->colo_incoming_thread, "COLO incoming",
420 colo_process_incoming_thread, mis, QEMU_THREAD_JOINABLE);
421 mis->have_colo_incoming_thread = true;
422 qemu_coroutine_yield();
423
424 /* Wait checkpoint incoming thread exit before free resource */
425 qemu_thread_join(&mis->colo_incoming_thread);
426 }
427
428 qemu_fclose(f);
429 free_xbzrle_decoded_buf();
430
431 if (ret < 0) {
432 migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
433 MIGRATION_STATUS_FAILED);
434 error_report("load of migration failed: %s", strerror(-ret));
435 migrate_decompress_threads_join();
436 exit(EXIT_FAILURE);
437 }
438
439 mis->bh = qemu_bh_new(process_incoming_migration_bh, mis);
440 qemu_bh_schedule(mis->bh);
441 }
442
443 void migration_fd_process_incoming(QEMUFile *f)
444 {
445 Coroutine *co = qemu_coroutine_create(process_incoming_migration_co, f);
446
447 migrate_decompress_threads_create();
448 qemu_file_set_blocking(f, false);
449 qemu_coroutine_enter(co);
450 }
451
452
453 void migration_channel_process_incoming(MigrationState *s,
454 QIOChannel *ioc)
455 {
456 trace_migration_set_incoming_channel(
457 ioc, object_get_typename(OBJECT(ioc)));
458
459 if (s->parameters.tls_creds &&
460 !object_dynamic_cast(OBJECT(ioc),
461 TYPE_QIO_CHANNEL_TLS)) {
462 Error *local_err = NULL;
463 migration_tls_channel_process_incoming(s, ioc, &local_err);
464 if (local_err) {
465 error_report_err(local_err);
466 }
467 } else {
468 QEMUFile *f = qemu_fopen_channel_input(ioc);
469 migration_fd_process_incoming(f);
470 }
471 }
472
473
474 void migration_channel_connect(MigrationState *s,
475 QIOChannel *ioc,
476 const char *hostname)
477 {
478 trace_migration_set_outgoing_channel(
479 ioc, object_get_typename(OBJECT(ioc)), hostname);
480
481 if (s->parameters.tls_creds &&
482 !object_dynamic_cast(OBJECT(ioc),
483 TYPE_QIO_CHANNEL_TLS)) {
484 Error *local_err = NULL;
485 migration_tls_channel_connect(s, ioc, hostname, &local_err);
486 if (local_err) {
487 migrate_fd_error(s, local_err);
488 error_free(local_err);
489 }
490 } else {
491 QEMUFile *f = qemu_fopen_channel_output(ioc);
492
493 s->to_dst_file = f;
494
495 migrate_fd_connect(s);
496 }
497 }
498
499
500 /*
501 * Send a message on the return channel back to the source
502 * of the migration.
503 */
504 void migrate_send_rp_message(MigrationIncomingState *mis,
505 enum mig_rp_message_type message_type,
506 uint16_t len, void *data)
507 {
508 trace_migrate_send_rp_message((int)message_type, len);
509 qemu_mutex_lock(&mis->rp_mutex);
510 qemu_put_be16(mis->to_src_file, (unsigned int)message_type);
511 qemu_put_be16(mis->to_src_file, len);
512 qemu_put_buffer(mis->to_src_file, data, len);
513 qemu_fflush(mis->to_src_file);
514 qemu_mutex_unlock(&mis->rp_mutex);
515 }
516
517 /*
518 * Send a 'SHUT' message on the return channel with the given value
519 * to indicate that we've finished with the RP. Non-0 value indicates
520 * error.
521 */
522 void migrate_send_rp_shut(MigrationIncomingState *mis,
523 uint32_t value)
524 {
525 uint32_t buf;
526
527 buf = cpu_to_be32(value);
528 migrate_send_rp_message(mis, MIG_RP_MSG_SHUT, sizeof(buf), &buf);
529 }
530
531 /*
532 * Send a 'PONG' message on the return channel with the given value
533 * (normally in response to a 'PING')
534 */
535 void migrate_send_rp_pong(MigrationIncomingState *mis,
536 uint32_t value)
537 {
538 uint32_t buf;
539
540 buf = cpu_to_be32(value);
541 migrate_send_rp_message(mis, MIG_RP_MSG_PONG, sizeof(buf), &buf);
542 }
543
544 MigrationCapabilityStatusList *qmp_query_migrate_capabilities(Error **errp)
545 {
546 MigrationCapabilityStatusList *head = NULL;
547 MigrationCapabilityStatusList *caps;
548 MigrationState *s = migrate_get_current();
549 int i;
550
551 caps = NULL; /* silence compiler warning */
552 for (i = 0; i < MIGRATION_CAPABILITY__MAX; i++) {
553 if (i == MIGRATION_CAPABILITY_X_COLO && !colo_supported()) {
554 continue;
555 }
556 if (head == NULL) {
557 head = g_malloc0(sizeof(*caps));
558 caps = head;
559 } else {
560 caps->next = g_malloc0(sizeof(*caps));
561 caps = caps->next;
562 }
563 caps->value =
564 g_malloc(sizeof(*caps->value));
565 caps->value->capability = i;
566 caps->value->state = s->enabled_capabilities[i];
567 }
568
569 return head;
570 }
571
572 MigrationParameters *qmp_query_migrate_parameters(Error **errp)
573 {
574 MigrationParameters *params;
575 MigrationState *s = migrate_get_current();
576
577 params = g_malloc0(sizeof(*params));
578 params->has_compress_level = true;
579 params->compress_level = s->parameters.compress_level;
580 params->has_compress_threads = true;
581 params->compress_threads = s->parameters.compress_threads;
582 params->has_decompress_threads = true;
583 params->decompress_threads = s->parameters.decompress_threads;
584 params->has_cpu_throttle_initial = true;
585 params->cpu_throttle_initial = s->parameters.cpu_throttle_initial;
586 params->has_cpu_throttle_increment = true;
587 params->cpu_throttle_increment = s->parameters.cpu_throttle_increment;
588 params->has_tls_creds = !!s->parameters.tls_creds;
589 params->tls_creds = g_strdup(s->parameters.tls_creds);
590 params->has_tls_hostname = !!s->parameters.tls_hostname;
591 params->tls_hostname = g_strdup(s->parameters.tls_hostname);
592 params->has_max_bandwidth = true;
593 params->max_bandwidth = s->parameters.max_bandwidth;
594 params->has_downtime_limit = true;
595 params->downtime_limit = s->parameters.downtime_limit;
596 params->has_x_checkpoint_delay = true;
597 params->x_checkpoint_delay = s->parameters.x_checkpoint_delay;
598
599 return params;
600 }
601
602 /*
603 * Return true if we're already in the middle of a migration
604 * (i.e. any of the active or setup states)
605 */
606 static bool migration_is_setup_or_active(int state)
607 {
608 switch (state) {
609 case MIGRATION_STATUS_ACTIVE:
610 case MIGRATION_STATUS_POSTCOPY_ACTIVE:
611 case MIGRATION_STATUS_SETUP:
612 return true;
613
614 default:
615 return false;
616
617 }
618 }
619
620 static void get_xbzrle_cache_stats(MigrationInfo *info)
621 {
622 if (migrate_use_xbzrle()) {
623 info->has_xbzrle_cache = true;
624 info->xbzrle_cache = g_malloc0(sizeof(*info->xbzrle_cache));
625 info->xbzrle_cache->cache_size = migrate_xbzrle_cache_size();
626 info->xbzrle_cache->bytes = xbzrle_mig_bytes_transferred();
627 info->xbzrle_cache->pages = xbzrle_mig_pages_transferred();
628 info->xbzrle_cache->cache_miss = xbzrle_mig_pages_cache_miss();
629 info->xbzrle_cache->cache_miss_rate = xbzrle_mig_cache_miss_rate();
630 info->xbzrle_cache->overflow = xbzrle_mig_pages_overflow();
631 }
632 }
633
634 static void populate_ram_info(MigrationInfo *info, MigrationState *s)
635 {
636 info->has_ram = true;
637 info->ram = g_malloc0(sizeof(*info->ram));
638 info->ram->transferred = ram_bytes_transferred();
639 info->ram->total = ram_bytes_total();
640 info->ram->duplicate = dup_mig_pages_transferred();
641 info->ram->skipped = skipped_mig_pages_transferred();
642 info->ram->normal = norm_mig_pages_transferred();
643 info->ram->normal_bytes = norm_mig_bytes_transferred();
644 info->ram->mbps = s->mbps;
645 info->ram->dirty_sync_count = s->dirty_sync_count;
646 info->ram->postcopy_requests = s->postcopy_requests;
647
648 if (s->state != MIGRATION_STATUS_COMPLETED) {
649 info->ram->remaining = ram_bytes_remaining();
650 info->ram->dirty_pages_rate = s->dirty_pages_rate;
651 }
652 }
653
654 MigrationInfo *qmp_query_migrate(Error **errp)
655 {
656 MigrationInfo *info = g_malloc0(sizeof(*info));
657 MigrationState *s = migrate_get_current();
658
659 switch (s->state) {
660 case MIGRATION_STATUS_NONE:
661 /* no migration has happened ever */
662 break;
663 case MIGRATION_STATUS_SETUP:
664 info->has_status = true;
665 info->has_total_time = false;
666 break;
667 case MIGRATION_STATUS_ACTIVE:
668 case MIGRATION_STATUS_CANCELLING:
669 info->has_status = true;
670 info->has_total_time = true;
671 info->total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME)
672 - s->total_time;
673 info->has_expected_downtime = true;
674 info->expected_downtime = s->expected_downtime;
675 info->has_setup_time = true;
676 info->setup_time = s->setup_time;
677
678 populate_ram_info(info, s);
679
680 if (blk_mig_active()) {
681 info->has_disk = true;
682 info->disk = g_malloc0(sizeof(*info->disk));
683 info->disk->transferred = blk_mig_bytes_transferred();
684 info->disk->remaining = blk_mig_bytes_remaining();
685 info->disk->total = blk_mig_bytes_total();
686 }
687
688 if (cpu_throttle_active()) {
689 info->has_cpu_throttle_percentage = true;
690 info->cpu_throttle_percentage = cpu_throttle_get_percentage();
691 }
692
693 get_xbzrle_cache_stats(info);
694 break;
695 case MIGRATION_STATUS_POSTCOPY_ACTIVE:
696 /* Mostly the same as active; TODO add some postcopy stats */
697 info->has_status = true;
698 info->has_total_time = true;
699 info->total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME)
700 - s->total_time;
701 info->has_expected_downtime = true;
702 info->expected_downtime = s->expected_downtime;
703 info->has_setup_time = true;
704 info->setup_time = s->setup_time;
705
706 populate_ram_info(info, s);
707
708 if (blk_mig_active()) {
709 info->has_disk = true;
710 info->disk = g_malloc0(sizeof(*info->disk));
711 info->disk->transferred = blk_mig_bytes_transferred();
712 info->disk->remaining = blk_mig_bytes_remaining();
713 info->disk->total = blk_mig_bytes_total();
714 }
715
716 get_xbzrle_cache_stats(info);
717 break;
718 case MIGRATION_STATUS_COLO:
719 info->has_status = true;
720 /* TODO: display COLO specific information (checkpoint info etc.) */
721 break;
722 case MIGRATION_STATUS_COMPLETED:
723 get_xbzrle_cache_stats(info);
724
725 info->has_status = true;
726 info->has_total_time = true;
727 info->total_time = s->total_time;
728 info->has_downtime = true;
729 info->downtime = s->downtime;
730 info->has_setup_time = true;
731 info->setup_time = s->setup_time;
732
733 populate_ram_info(info, s);
734 break;
735 case MIGRATION_STATUS_FAILED:
736 info->has_status = true;
737 if (s->error) {
738 info->has_error_desc = true;
739 info->error_desc = g_strdup(error_get_pretty(s->error));
740 }
741 break;
742 case MIGRATION_STATUS_CANCELLED:
743 info->has_status = true;
744 break;
745 }
746 info->status = s->state;
747
748 return info;
749 }
750
751 void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params,
752 Error **errp)
753 {
754 MigrationState *s = migrate_get_current();
755 MigrationCapabilityStatusList *cap;
756 bool old_postcopy_cap = migrate_postcopy_ram();
757
758 if (migration_is_setup_or_active(s->state)) {
759 error_setg(errp, QERR_MIGRATION_ACTIVE);
760 return;
761 }
762
763 for (cap = params; cap; cap = cap->next) {
764 if (cap->value->capability == MIGRATION_CAPABILITY_X_COLO) {
765 if (!colo_supported()) {
766 error_setg(errp, "COLO is not currently supported, please"
767 " configure with --enable-colo option in order to"
768 " support COLO feature");
769 continue;
770 }
771 }
772 s->enabled_capabilities[cap->value->capability] = cap->value->state;
773 }
774
775 if (migrate_postcopy_ram()) {
776 if (migrate_use_compression()) {
777 /* The decompression threads asynchronously write into RAM
778 * rather than use the atomic copies needed to avoid
779 * userfaulting. It should be possible to fix the decompression
780 * threads for compatibility in future.
781 */
782 error_report("Postcopy is not currently compatible with "
783 "compression");
784 s->enabled_capabilities[MIGRATION_CAPABILITY_POSTCOPY_RAM] =
785 false;
786 }
787 /* This check is reasonably expensive, so only when it's being
788 * set the first time, also it's only the destination that needs
789 * special support.
790 */
791 if (!old_postcopy_cap && runstate_check(RUN_STATE_INMIGRATE) &&
792 !postcopy_ram_supported_by_host()) {
793 /* postcopy_ram_supported_by_host will have emitted a more
794 * detailed message
795 */
796 error_report("Postcopy is not supported");
797 s->enabled_capabilities[MIGRATION_CAPABILITY_POSTCOPY_RAM] =
798 false;
799 }
800 }
801 }
802
803 void qmp_migrate_set_parameters(MigrationParameters *params, Error **errp)
804 {
805 MigrationState *s = migrate_get_current();
806
807 if (params->has_compress_level &&
808 (params->compress_level < 0 || params->compress_level > 9)) {
809 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "compress_level",
810 "is invalid, it should be in the range of 0 to 9");
811 return;
812 }
813 if (params->has_compress_threads &&
814 (params->compress_threads < 1 || params->compress_threads > 255)) {
815 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
816 "compress_threads",
817 "is invalid, it should be in the range of 1 to 255");
818 return;
819 }
820 if (params->has_decompress_threads &&
821 (params->decompress_threads < 1 || params->decompress_threads > 255)) {
822 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
823 "decompress_threads",
824 "is invalid, it should be in the range of 1 to 255");
825 return;
826 }
827 if (params->has_cpu_throttle_initial &&
828 (params->cpu_throttle_initial < 1 ||
829 params->cpu_throttle_initial > 99)) {
830 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
831 "cpu_throttle_initial",
832 "an integer in the range of 1 to 99");
833 return;
834 }
835 if (params->has_cpu_throttle_increment &&
836 (params->cpu_throttle_increment < 1 ||
837 params->cpu_throttle_increment > 99)) {
838 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
839 "cpu_throttle_increment",
840 "an integer in the range of 1 to 99");
841 return;
842 }
843 if (params->has_max_bandwidth &&
844 (params->max_bandwidth < 0 || params->max_bandwidth > SIZE_MAX)) {
845 error_setg(errp, "Parameter 'max_bandwidth' expects an integer in the"
846 " range of 0 to %zu bytes/second", SIZE_MAX);
847 return;
848 }
849 if (params->has_downtime_limit &&
850 (params->downtime_limit < 0 || params->downtime_limit > 2000000)) {
851 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
852 "downtime_limit",
853 "an integer in the range of 0 to 2000000 milliseconds");
854 return;
855 }
856 if (params->has_x_checkpoint_delay && (params->x_checkpoint_delay < 0)) {
857 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
858 "x_checkpoint_delay",
859 "is invalid, it should be positive");
860 }
861
862 if (params->has_compress_level) {
863 s->parameters.compress_level = params->compress_level;
864 }
865 if (params->has_compress_threads) {
866 s->parameters.compress_threads = params->compress_threads;
867 }
868 if (params->has_decompress_threads) {
869 s->parameters.decompress_threads = params->decompress_threads;
870 }
871 if (params->has_cpu_throttle_initial) {
872 s->parameters.cpu_throttle_initial = params->cpu_throttle_initial;
873 }
874 if (params->has_cpu_throttle_increment) {
875 s->parameters.cpu_throttle_increment = params->cpu_throttle_increment;
876 }
877 if (params->has_tls_creds) {
878 g_free(s->parameters.tls_creds);
879 s->parameters.tls_creds = g_strdup(params->tls_creds);
880 }
881 if (params->has_tls_hostname) {
882 g_free(s->parameters.tls_hostname);
883 s->parameters.tls_hostname = g_strdup(params->tls_hostname);
884 }
885 if (params->has_max_bandwidth) {
886 s->parameters.max_bandwidth = params->max_bandwidth;
887 if (s->to_dst_file) {
888 qemu_file_set_rate_limit(s->to_dst_file,
889 s->parameters.max_bandwidth / XFER_LIMIT_RATIO);
890 }
891 }
892 if (params->has_downtime_limit) {
893 s->parameters.downtime_limit = params->downtime_limit;
894 }
895
896 if (params->has_x_checkpoint_delay) {
897 s->parameters.x_checkpoint_delay = params->x_checkpoint_delay;
898 }
899 }
900
901
902 void qmp_migrate_start_postcopy(Error **errp)
903 {
904 MigrationState *s = migrate_get_current();
905
906 if (!migrate_postcopy_ram()) {
907 error_setg(errp, "Enable postcopy with migrate_set_capability before"
908 " the start of migration");
909 return;
910 }
911
912 if (s->state == MIGRATION_STATUS_NONE) {
913 error_setg(errp, "Postcopy must be started after migration has been"
914 " started");
915 return;
916 }
917 /*
918 * we don't error if migration has finished since that would be racy
919 * with issuing this command.
920 */
921 atomic_set(&s->start_postcopy, true);
922 }
923
924 /* shared migration helpers */
925
926 void migrate_set_state(int *state, int old_state, int new_state)
927 {
928 if (atomic_cmpxchg(state, old_state, new_state) == old_state) {
929 trace_migrate_set_state(new_state);
930 migrate_generate_event(new_state);
931 }
932 }
933
934 static void migrate_fd_cleanup(void *opaque)
935 {
936 MigrationState *s = opaque;
937
938 qemu_bh_delete(s->cleanup_bh);
939 s->cleanup_bh = NULL;
940
941 flush_page_queue(s);
942
943 if (s->to_dst_file) {
944 trace_migrate_fd_cleanup();
945 qemu_mutex_unlock_iothread();
946 if (s->migration_thread_running) {
947 qemu_thread_join(&s->thread);
948 s->migration_thread_running = false;
949 }
950 qemu_mutex_lock_iothread();
951
952 migrate_compress_threads_join();
953 qemu_fclose(s->to_dst_file);
954 s->to_dst_file = NULL;
955 }
956
957 assert((s->state != MIGRATION_STATUS_ACTIVE) &&
958 (s->state != MIGRATION_STATUS_POSTCOPY_ACTIVE));
959
960 if (s->state == MIGRATION_STATUS_CANCELLING) {
961 migrate_set_state(&s->state, MIGRATION_STATUS_CANCELLING,
962 MIGRATION_STATUS_CANCELLED);
963 }
964
965 notifier_list_notify(&migration_state_notifiers, s);
966 }
967
968 void migrate_fd_error(MigrationState *s, const Error *error)
969 {
970 trace_migrate_fd_error(error_get_pretty(error));
971 assert(s->to_dst_file == NULL);
972 migrate_set_state(&s->state, MIGRATION_STATUS_SETUP,
973 MIGRATION_STATUS_FAILED);
974 if (!s->error) {
975 s->error = error_copy(error);
976 }
977 notifier_list_notify(&migration_state_notifiers, s);
978 }
979
980 static void migrate_fd_cancel(MigrationState *s)
981 {
982 int old_state ;
983 QEMUFile *f = migrate_get_current()->to_dst_file;
984 trace_migrate_fd_cancel();
985
986 if (s->rp_state.from_dst_file) {
987 /* shutdown the rp socket, so causing the rp thread to shutdown */
988 qemu_file_shutdown(s->rp_state.from_dst_file);
989 }
990
991 do {
992 old_state = s->state;
993 if (!migration_is_setup_or_active(old_state)) {
994 break;
995 }
996 migrate_set_state(&s->state, old_state, MIGRATION_STATUS_CANCELLING);
997 } while (s->state != MIGRATION_STATUS_CANCELLING);
998
999 /*
1000 * If we're unlucky the migration code might be stuck somewhere in a
1001 * send/write while the network has failed and is waiting to timeout;
1002 * if we've got shutdown(2) available then we can force it to quit.
1003 * The outgoing qemu file gets closed in migrate_fd_cleanup that is
1004 * called in a bh, so there is no race against this cancel.
1005 */
1006 if (s->state == MIGRATION_STATUS_CANCELLING && f) {
1007 qemu_file_shutdown(f);
1008 }
1009 }
1010
1011 void add_migration_state_change_notifier(Notifier *notify)
1012 {
1013 notifier_list_add(&migration_state_notifiers, notify);
1014 }
1015
1016 void remove_migration_state_change_notifier(Notifier *notify)
1017 {
1018 notifier_remove(notify);
1019 }
1020
1021 bool migration_in_setup(MigrationState *s)
1022 {
1023 return s->state == MIGRATION_STATUS_SETUP;
1024 }
1025
1026 bool migration_has_finished(MigrationState *s)
1027 {
1028 return s->state == MIGRATION_STATUS_COMPLETED;
1029 }
1030
1031 bool migration_has_failed(MigrationState *s)
1032 {
1033 return (s->state == MIGRATION_STATUS_CANCELLED ||
1034 s->state == MIGRATION_STATUS_FAILED);
1035 }
1036
1037 bool migration_in_postcopy(MigrationState *s)
1038 {
1039 return (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE);
1040 }
1041
1042 bool migration_in_postcopy_after_devices(MigrationState *s)
1043 {
1044 return migration_in_postcopy(s) && s->postcopy_after_devices;
1045 }
1046
1047 MigrationState *migrate_init(const MigrationParams *params)
1048 {
1049 MigrationState *s = migrate_get_current();
1050
1051 /*
1052 * Reinitialise all migration state, except
1053 * parameters/capabilities that the user set, and
1054 * locks.
1055 */
1056 s->bytes_xfer = 0;
1057 s->xfer_limit = 0;
1058 s->cleanup_bh = 0;
1059 s->to_dst_file = NULL;
1060 s->state = MIGRATION_STATUS_NONE;
1061 s->params = *params;
1062 s->rp_state.from_dst_file = NULL;
1063 s->rp_state.error = false;
1064 s->mbps = 0.0;
1065 s->downtime = 0;
1066 s->expected_downtime = 0;
1067 s->dirty_pages_rate = 0;
1068 s->dirty_bytes_rate = 0;
1069 s->setup_time = 0;
1070 s->dirty_sync_count = 0;
1071 s->start_postcopy = false;
1072 s->postcopy_after_devices = false;
1073 s->postcopy_requests = 0;
1074 s->migration_thread_running = false;
1075 s->last_req_rb = NULL;
1076 error_free(s->error);
1077 s->error = NULL;
1078
1079 migrate_set_state(&s->state, MIGRATION_STATUS_NONE, MIGRATION_STATUS_SETUP);
1080
1081 QSIMPLEQ_INIT(&s->src_page_requests);
1082
1083 s->total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
1084 return s;
1085 }
1086
1087 static GSList *migration_blockers;
1088
1089 void migrate_add_blocker(Error *reason)
1090 {
1091 migration_blockers = g_slist_prepend(migration_blockers, reason);
1092 }
1093
1094 void migrate_del_blocker(Error *reason)
1095 {
1096 migration_blockers = g_slist_remove(migration_blockers, reason);
1097 }
1098
1099 void qmp_migrate_incoming(const char *uri, Error **errp)
1100 {
1101 Error *local_err = NULL;
1102 static bool once = true;
1103
1104 if (!deferred_incoming) {
1105 error_setg(errp, "For use with '-incoming defer'");
1106 return;
1107 }
1108 if (!once) {
1109 error_setg(errp, "The incoming migration has already been started");
1110 }
1111
1112 qemu_start_incoming_migration(uri, &local_err);
1113
1114 if (local_err) {
1115 error_propagate(errp, local_err);
1116 return;
1117 }
1118
1119 once = false;
1120 }
1121
1122 bool migration_is_blocked(Error **errp)
1123 {
1124 if (qemu_savevm_state_blocked(errp)) {
1125 return true;
1126 }
1127
1128 if (migration_blockers) {
1129 *errp = error_copy(migration_blockers->data);
1130 return true;
1131 }
1132
1133 return false;
1134 }
1135
1136 void qmp_migrate(const char *uri, bool has_blk, bool blk,
1137 bool has_inc, bool inc, bool has_detach, bool detach,
1138 Error **errp)
1139 {
1140 Error *local_err = NULL;
1141 MigrationState *s = migrate_get_current();
1142 MigrationParams params;
1143 const char *p;
1144
1145 params.blk = has_blk && blk;
1146 params.shared = has_inc && inc;
1147
1148 if (migration_is_setup_or_active(s->state) ||
1149 s->state == MIGRATION_STATUS_CANCELLING ||
1150 s->state == MIGRATION_STATUS_COLO) {
1151 error_setg(errp, QERR_MIGRATION_ACTIVE);
1152 return;
1153 }
1154 if (runstate_check(RUN_STATE_INMIGRATE)) {
1155 error_setg(errp, "Guest is waiting for an incoming migration");
1156 return;
1157 }
1158
1159 if (migration_is_blocked(errp)) {
1160 return;
1161 }
1162
1163 s = migrate_init(&params);
1164
1165 if (strstart(uri, "tcp:", &p)) {
1166 tcp_start_outgoing_migration(s, p, &local_err);
1167 #ifdef CONFIG_RDMA
1168 } else if (strstart(uri, "rdma:", &p)) {
1169 rdma_start_outgoing_migration(s, p, &local_err);
1170 #endif
1171 } else if (strstart(uri, "exec:", &p)) {
1172 exec_start_outgoing_migration(s, p, &local_err);
1173 } else if (strstart(uri, "unix:", &p)) {
1174 unix_start_outgoing_migration(s, p, &local_err);
1175 } else if (strstart(uri, "fd:", &p)) {
1176 fd_start_outgoing_migration(s, p, &local_err);
1177 } else {
1178 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "uri",
1179 "a valid migration protocol");
1180 migrate_set_state(&s->state, MIGRATION_STATUS_SETUP,
1181 MIGRATION_STATUS_FAILED);
1182 return;
1183 }
1184
1185 if (local_err) {
1186 migrate_fd_error(s, local_err);
1187 error_propagate(errp, local_err);
1188 return;
1189 }
1190 }
1191
1192 void qmp_migrate_cancel(Error **errp)
1193 {
1194 migrate_fd_cancel(migrate_get_current());
1195 }
1196
1197 void qmp_migrate_set_cache_size(int64_t value, Error **errp)
1198 {
1199 MigrationState *s = migrate_get_current();
1200 int64_t new_size;
1201
1202 /* Check for truncation */
1203 if (value != (size_t)value) {
1204 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cache size",
1205 "exceeding address space");
1206 return;
1207 }
1208
1209 /* Cache should not be larger than guest ram size */
1210 if (value > ram_bytes_total()) {
1211 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cache size",
1212 "exceeds guest ram size ");
1213 return;
1214 }
1215
1216 new_size = xbzrle_cache_resize(value);
1217 if (new_size < 0) {
1218 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "cache size",
1219 "is smaller than page size");
1220 return;
1221 }
1222
1223 s->xbzrle_cache_size = new_size;
1224 }
1225
1226 int64_t qmp_query_migrate_cache_size(Error **errp)
1227 {
1228 return migrate_xbzrle_cache_size();
1229 }
1230
1231 void qmp_migrate_set_speed(int64_t value, Error **errp)
1232 {
1233 MigrationParameters p = {
1234 .has_max_bandwidth = true,
1235 .max_bandwidth = value,
1236 };
1237
1238 qmp_migrate_set_parameters(&p, errp);
1239 }
1240
1241 void qmp_migrate_set_downtime(double value, Error **errp)
1242 {
1243 value *= 1000; /* Convert to milliseconds */
1244 value = MAX(0, MIN(INT64_MAX, value));
1245
1246 MigrationParameters p = {
1247 .has_downtime_limit = true,
1248 .downtime_limit = value,
1249 };
1250
1251 qmp_migrate_set_parameters(&p, errp);
1252 }
1253
1254 bool migrate_postcopy_ram(void)
1255 {
1256 MigrationState *s;
1257
1258 s = migrate_get_current();
1259
1260 return s->enabled_capabilities[MIGRATION_CAPABILITY_POSTCOPY_RAM];
1261 }
1262
1263 bool migrate_auto_converge(void)
1264 {
1265 MigrationState *s;
1266
1267 s = migrate_get_current();
1268
1269 return s->enabled_capabilities[MIGRATION_CAPABILITY_AUTO_CONVERGE];
1270 }
1271
1272 bool migrate_zero_blocks(void)
1273 {
1274 MigrationState *s;
1275
1276 s = migrate_get_current();
1277
1278 return s->enabled_capabilities[MIGRATION_CAPABILITY_ZERO_BLOCKS];
1279 }
1280
1281 bool migrate_use_compression(void)
1282 {
1283 MigrationState *s;
1284
1285 s = migrate_get_current();
1286
1287 return s->enabled_capabilities[MIGRATION_CAPABILITY_COMPRESS];
1288 }
1289
1290 int migrate_compress_level(void)
1291 {
1292 MigrationState *s;
1293
1294 s = migrate_get_current();
1295
1296 return s->parameters.compress_level;
1297 }
1298
1299 int migrate_compress_threads(void)
1300 {
1301 MigrationState *s;
1302
1303 s = migrate_get_current();
1304
1305 return s->parameters.compress_threads;
1306 }
1307
1308 int migrate_decompress_threads(void)
1309 {
1310 MigrationState *s;
1311
1312 s = migrate_get_current();
1313
1314 return s->parameters.decompress_threads;
1315 }
1316
1317 bool migrate_use_events(void)
1318 {
1319 MigrationState *s;
1320
1321 s = migrate_get_current();
1322
1323 return s->enabled_capabilities[MIGRATION_CAPABILITY_EVENTS];
1324 }
1325
1326 int migrate_use_xbzrle(void)
1327 {
1328 MigrationState *s;
1329
1330 s = migrate_get_current();
1331
1332 return s->enabled_capabilities[MIGRATION_CAPABILITY_XBZRLE];
1333 }
1334
1335 int64_t migrate_xbzrle_cache_size(void)
1336 {
1337 MigrationState *s;
1338
1339 s = migrate_get_current();
1340
1341 return s->xbzrle_cache_size;
1342 }
1343
1344 /* migration thread support */
1345 /*
1346 * Something bad happened to the RP stream, mark an error
1347 * The caller shall print or trace something to indicate why
1348 */
1349 static void mark_source_rp_bad(MigrationState *s)
1350 {
1351 s->rp_state.error = true;
1352 }
1353
1354 static struct rp_cmd_args {
1355 ssize_t len; /* -1 = variable */
1356 const char *name;
1357 } rp_cmd_args[] = {
1358 [MIG_RP_MSG_INVALID] = { .len = -1, .name = "INVALID" },
1359 [MIG_RP_MSG_SHUT] = { .len = 4, .name = "SHUT" },
1360 [MIG_RP_MSG_PONG] = { .len = 4, .name = "PONG" },
1361 [MIG_RP_MSG_REQ_PAGES] = { .len = 12, .name = "REQ_PAGES" },
1362 [MIG_RP_MSG_REQ_PAGES_ID] = { .len = -1, .name = "REQ_PAGES_ID" },
1363 [MIG_RP_MSG_MAX] = { .len = -1, .name = "MAX" },
1364 };
1365
1366 /*
1367 * Process a request for pages received on the return path,
1368 * We're allowed to send more than requested (e.g. to round to our page size)
1369 * and we don't need to send pages that have already been sent.
1370 */
1371 static void migrate_handle_rp_req_pages(MigrationState *ms, const char* rbname,
1372 ram_addr_t start, size_t len)
1373 {
1374 long our_host_ps = getpagesize();
1375
1376 trace_migrate_handle_rp_req_pages(rbname, start, len);
1377
1378 /*
1379 * Since we currently insist on matching page sizes, just sanity check
1380 * we're being asked for whole host pages.
1381 */
1382 if (start & (our_host_ps-1) ||
1383 (len & (our_host_ps-1))) {
1384 error_report("%s: Misaligned page request, start: " RAM_ADDR_FMT
1385 " len: %zd", __func__, start, len);
1386 mark_source_rp_bad(ms);
1387 return;
1388 }
1389
1390 if (ram_save_queue_pages(ms, rbname, start, len)) {
1391 mark_source_rp_bad(ms);
1392 }
1393 }
1394
1395 /*
1396 * Handles messages sent on the return path towards the source VM
1397 *
1398 */
1399 static void *source_return_path_thread(void *opaque)
1400 {
1401 MigrationState *ms = opaque;
1402 QEMUFile *rp = ms->rp_state.from_dst_file;
1403 uint16_t header_len, header_type;
1404 uint8_t buf[512];
1405 uint32_t tmp32, sibling_error;
1406 ram_addr_t start = 0; /* =0 to silence warning */
1407 size_t len = 0, expected_len;
1408 int res;
1409
1410 trace_source_return_path_thread_entry();
1411 while (!ms->rp_state.error && !qemu_file_get_error(rp) &&
1412 migration_is_setup_or_active(ms->state)) {
1413 trace_source_return_path_thread_loop_top();
1414 header_type = qemu_get_be16(rp);
1415 header_len = qemu_get_be16(rp);
1416
1417 if (header_type >= MIG_RP_MSG_MAX ||
1418 header_type == MIG_RP_MSG_INVALID) {
1419 error_report("RP: Received invalid message 0x%04x length 0x%04x",
1420 header_type, header_len);
1421 mark_source_rp_bad(ms);
1422 goto out;
1423 }
1424
1425 if ((rp_cmd_args[header_type].len != -1 &&
1426 header_len != rp_cmd_args[header_type].len) ||
1427 header_len > sizeof(buf)) {
1428 error_report("RP: Received '%s' message (0x%04x) with"
1429 "incorrect length %d expecting %zu",
1430 rp_cmd_args[header_type].name, header_type, header_len,
1431 (size_t)rp_cmd_args[header_type].len);
1432 mark_source_rp_bad(ms);
1433 goto out;
1434 }
1435
1436 /* We know we've got a valid header by this point */
1437 res = qemu_get_buffer(rp, buf, header_len);
1438 if (res != header_len) {
1439 error_report("RP: Failed reading data for message 0x%04x"
1440 " read %d expected %d",
1441 header_type, res, header_len);
1442 mark_source_rp_bad(ms);
1443 goto out;
1444 }
1445
1446 /* OK, we have the message and the data */
1447 switch (header_type) {
1448 case MIG_RP_MSG_SHUT:
1449 sibling_error = ldl_be_p(buf);
1450 trace_source_return_path_thread_shut(sibling_error);
1451 if (sibling_error) {
1452 error_report("RP: Sibling indicated error %d", sibling_error);
1453 mark_source_rp_bad(ms);
1454 }
1455 /*
1456 * We'll let the main thread deal with closing the RP
1457 * we could do a shutdown(2) on it, but we're the only user
1458 * anyway, so there's nothing gained.
1459 */
1460 goto out;
1461
1462 case MIG_RP_MSG_PONG:
1463 tmp32 = ldl_be_p(buf);
1464 trace_source_return_path_thread_pong(tmp32);
1465 break;
1466
1467 case MIG_RP_MSG_REQ_PAGES:
1468 start = ldq_be_p(buf);
1469 len = ldl_be_p(buf + 8);
1470 migrate_handle_rp_req_pages(ms, NULL, start, len);
1471 break;
1472
1473 case MIG_RP_MSG_REQ_PAGES_ID:
1474 expected_len = 12 + 1; /* header + termination */
1475
1476 if (header_len >= expected_len) {
1477 start = ldq_be_p(buf);
1478 len = ldl_be_p(buf + 8);
1479 /* Now we expect an idstr */
1480 tmp32 = buf[12]; /* Length of the following idstr */
1481 buf[13 + tmp32] = '\0';
1482 expected_len += tmp32;
1483 }
1484 if (header_len != expected_len) {
1485 error_report("RP: Req_Page_id with length %d expecting %zd",
1486 header_len, expected_len);
1487 mark_source_rp_bad(ms);
1488 goto out;
1489 }
1490 migrate_handle_rp_req_pages(ms, (char *)&buf[13], start, len);
1491 break;
1492
1493 default:
1494 break;
1495 }
1496 }
1497 if (qemu_file_get_error(rp)) {
1498 trace_source_return_path_thread_bad_end();
1499 mark_source_rp_bad(ms);
1500 }
1501
1502 trace_source_return_path_thread_end();
1503 out:
1504 ms->rp_state.from_dst_file = NULL;
1505 qemu_fclose(rp);
1506 return NULL;
1507 }
1508
1509 static int open_return_path_on_source(MigrationState *ms)
1510 {
1511
1512 ms->rp_state.from_dst_file = qemu_file_get_return_path(ms->to_dst_file);
1513 if (!ms->rp_state.from_dst_file) {
1514 return -1;
1515 }
1516
1517 trace_open_return_path_on_source();
1518 qemu_thread_create(&ms->rp_state.rp_thread, "return path",
1519 source_return_path_thread, ms, QEMU_THREAD_JOINABLE);
1520
1521 trace_open_return_path_on_source_continue();
1522
1523 return 0;
1524 }
1525
1526 /* Returns 0 if the RP was ok, otherwise there was an error on the RP */
1527 static int await_return_path_close_on_source(MigrationState *ms)
1528 {
1529 /*
1530 * If this is a normal exit then the destination will send a SHUT and the
1531 * rp_thread will exit, however if there's an error we need to cause
1532 * it to exit.
1533 */
1534 if (qemu_file_get_error(ms->to_dst_file) && ms->rp_state.from_dst_file) {
1535 /*
1536 * shutdown(2), if we have it, will cause it to unblock if it's stuck
1537 * waiting for the destination.
1538 */
1539 qemu_file_shutdown(ms->rp_state.from_dst_file);
1540 mark_source_rp_bad(ms);
1541 }
1542 trace_await_return_path_close_on_source_joining();
1543 qemu_thread_join(&ms->rp_state.rp_thread);
1544 trace_await_return_path_close_on_source_close();
1545 return ms->rp_state.error;
1546 }
1547
1548 /*
1549 * Switch from normal iteration to postcopy
1550 * Returns non-0 on error
1551 */
1552 static int postcopy_start(MigrationState *ms, bool *old_vm_running)
1553 {
1554 int ret;
1555 QIOChannelBuffer *bioc;
1556 QEMUFile *fb;
1557 int64_t time_at_stop = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
1558 migrate_set_state(&ms->state, MIGRATION_STATUS_ACTIVE,
1559 MIGRATION_STATUS_POSTCOPY_ACTIVE);
1560
1561 trace_postcopy_start();
1562 qemu_mutex_lock_iothread();
1563 trace_postcopy_start_set_run();
1564
1565 qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
1566 *old_vm_running = runstate_is_running();
1567 global_state_store();
1568 ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
1569 if (ret < 0) {
1570 goto fail;
1571 }
1572
1573 ret = bdrv_inactivate_all();
1574 if (ret < 0) {
1575 goto fail;
1576 }
1577
1578 /*
1579 * Cause any non-postcopiable, but iterative devices to
1580 * send out their final data.
1581 */
1582 qemu_savevm_state_complete_precopy(ms->to_dst_file, true);
1583
1584 /*
1585 * in Finish migrate and with the io-lock held everything should
1586 * be quiet, but we've potentially still got dirty pages and we
1587 * need to tell the destination to throw any pages it's already received
1588 * that are dirty
1589 */
1590 if (ram_postcopy_send_discard_bitmap(ms)) {
1591 error_report("postcopy send discard bitmap failed");
1592 goto fail;
1593 }
1594
1595 /*
1596 * send rest of state - note things that are doing postcopy
1597 * will notice we're in POSTCOPY_ACTIVE and not actually
1598 * wrap their state up here
1599 */
1600 qemu_file_set_rate_limit(ms->to_dst_file, INT64_MAX);
1601 /* Ping just for debugging, helps line traces up */
1602 qemu_savevm_send_ping(ms->to_dst_file, 2);
1603
1604 /*
1605 * While loading the device state we may trigger page transfer
1606 * requests and the fd must be free to process those, and thus
1607 * the destination must read the whole device state off the fd before
1608 * it starts processing it. Unfortunately the ad-hoc migration format
1609 * doesn't allow the destination to know the size to read without fully
1610 * parsing it through each devices load-state code (especially the open
1611 * coded devices that use get/put).
1612 * So we wrap the device state up in a package with a length at the start;
1613 * to do this we use a qemu_buf to hold the whole of the device state.
1614 */
1615 bioc = qio_channel_buffer_new(4096);
1616 qio_channel_set_name(QIO_CHANNEL(bioc), "migration-postcopy-buffer");
1617 fb = qemu_fopen_channel_output(QIO_CHANNEL(bioc));
1618 object_unref(OBJECT(bioc));
1619
1620 /*
1621 * Make sure the receiver can get incoming pages before we send the rest
1622 * of the state
1623 */
1624 qemu_savevm_send_postcopy_listen(fb);
1625
1626 qemu_savevm_state_complete_precopy(fb, false);
1627 qemu_savevm_send_ping(fb, 3);
1628
1629 qemu_savevm_send_postcopy_run(fb);
1630
1631 /* <><> end of stuff going into the package */
1632
1633 /* Now send that blob */
1634 if (qemu_savevm_send_packaged(ms->to_dst_file, bioc->data, bioc->usage)) {
1635 goto fail_closefb;
1636 }
1637 qemu_fclose(fb);
1638
1639 /* Send a notify to give a chance for anything that needs to happen
1640 * at the transition to postcopy and after the device state; in particular
1641 * spice needs to trigger a transition now
1642 */
1643 ms->postcopy_after_devices = true;
1644 notifier_list_notify(&migration_state_notifiers, ms);
1645
1646 ms->downtime = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) - time_at_stop;
1647
1648 qemu_mutex_unlock_iothread();
1649
1650 /*
1651 * Although this ping is just for debug, it could potentially be
1652 * used for getting a better measurement of downtime at the source.
1653 */
1654 qemu_savevm_send_ping(ms->to_dst_file, 4);
1655
1656 ret = qemu_file_get_error(ms->to_dst_file);
1657 if (ret) {
1658 error_report("postcopy_start: Migration stream errored");
1659 migrate_set_state(&ms->state, MIGRATION_STATUS_POSTCOPY_ACTIVE,
1660 MIGRATION_STATUS_FAILED);
1661 }
1662
1663 return ret;
1664
1665 fail_closefb:
1666 qemu_fclose(fb);
1667 fail:
1668 migrate_set_state(&ms->state, MIGRATION_STATUS_POSTCOPY_ACTIVE,
1669 MIGRATION_STATUS_FAILED);
1670 qemu_mutex_unlock_iothread();
1671 return -1;
1672 }
1673
1674 /**
1675 * migration_completion: Used by migration_thread when there's not much left.
1676 * The caller 'breaks' the loop when this returns.
1677 *
1678 * @s: Current migration state
1679 * @current_active_state: The migration state we expect to be in
1680 * @*old_vm_running: Pointer to old_vm_running flag
1681 * @*start_time: Pointer to time to update
1682 */
1683 static void migration_completion(MigrationState *s, int current_active_state,
1684 bool *old_vm_running,
1685 int64_t *start_time)
1686 {
1687 int ret;
1688
1689 if (s->state == MIGRATION_STATUS_ACTIVE) {
1690 qemu_mutex_lock_iothread();
1691 *start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
1692 qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
1693 *old_vm_running = runstate_is_running();
1694 ret = global_state_store();
1695
1696 if (!ret) {
1697 ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
1698 /*
1699 * Don't mark the image with BDRV_O_INACTIVE flag if
1700 * we will go into COLO stage later.
1701 */
1702 if (ret >= 0 && !migrate_colo_enabled()) {
1703 ret = bdrv_inactivate_all();
1704 }
1705 if (ret >= 0) {
1706 qemu_file_set_rate_limit(s->to_dst_file, INT64_MAX);
1707 qemu_savevm_state_complete_precopy(s->to_dst_file, false);
1708 }
1709 }
1710 qemu_mutex_unlock_iothread();
1711
1712 if (ret < 0) {
1713 goto fail;
1714 }
1715 } else if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) {
1716 trace_migration_completion_postcopy_end();
1717
1718 qemu_savevm_state_complete_postcopy(s->to_dst_file);
1719 trace_migration_completion_postcopy_end_after_complete();
1720 }
1721
1722 /*
1723 * If rp was opened we must clean up the thread before
1724 * cleaning everything else up (since if there are no failures
1725 * it will wait for the destination to send it's status in
1726 * a SHUT command).
1727 * Postcopy opens rp if enabled (even if it's not avtivated)
1728 */
1729 if (migrate_postcopy_ram()) {
1730 int rp_error;
1731 trace_migration_completion_postcopy_end_before_rp();
1732 rp_error = await_return_path_close_on_source(s);
1733 trace_migration_completion_postcopy_end_after_rp(rp_error);
1734 if (rp_error) {
1735 goto fail_invalidate;
1736 }
1737 }
1738
1739 if (qemu_file_get_error(s->to_dst_file)) {
1740 trace_migration_completion_file_err();
1741 goto fail_invalidate;
1742 }
1743
1744 if (!migrate_colo_enabled()) {
1745 migrate_set_state(&s->state, current_active_state,
1746 MIGRATION_STATUS_COMPLETED);
1747 }
1748
1749 return;
1750
1751 fail_invalidate:
1752 /* If not doing postcopy, vm_start() will be called: let's regain
1753 * control on images.
1754 */
1755 if (s->state == MIGRATION_STATUS_ACTIVE) {
1756 Error *local_err = NULL;
1757
1758 bdrv_invalidate_cache_all(&local_err);
1759 if (local_err) {
1760 error_report_err(local_err);
1761 }
1762 }
1763
1764 fail:
1765 migrate_set_state(&s->state, current_active_state,
1766 MIGRATION_STATUS_FAILED);
1767 }
1768
1769 bool migrate_colo_enabled(void)
1770 {
1771 MigrationState *s = migrate_get_current();
1772 return s->enabled_capabilities[MIGRATION_CAPABILITY_X_COLO];
1773 }
1774
1775 /*
1776 * Master migration thread on the source VM.
1777 * It drives the migration and pumps the data down the outgoing channel.
1778 */
1779 static void *migration_thread(void *opaque)
1780 {
1781 MigrationState *s = opaque;
1782 /* Used by the bandwidth calcs, updated later */
1783 int64_t initial_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
1784 int64_t setup_start = qemu_clock_get_ms(QEMU_CLOCK_HOST);
1785 int64_t initial_bytes = 0;
1786 int64_t max_size = 0;
1787 int64_t start_time = initial_time;
1788 int64_t end_time;
1789 bool old_vm_running = false;
1790 bool entered_postcopy = false;
1791 /* The active state we expect to be in; ACTIVE or POSTCOPY_ACTIVE */
1792 enum MigrationStatus current_active_state = MIGRATION_STATUS_ACTIVE;
1793 bool enable_colo = migrate_colo_enabled();
1794
1795 rcu_register_thread();
1796
1797 qemu_savevm_state_header(s->to_dst_file);
1798
1799 if (migrate_postcopy_ram()) {
1800 /* Now tell the dest that it should open its end so it can reply */
1801 qemu_savevm_send_open_return_path(s->to_dst_file);
1802
1803 /* And do a ping that will make stuff easier to debug */
1804 qemu_savevm_send_ping(s->to_dst_file, 1);
1805
1806 /*
1807 * Tell the destination that we *might* want to do postcopy later;
1808 * if the other end can't do postcopy it should fail now, nice and
1809 * early.
1810 */
1811 qemu_savevm_send_postcopy_advise(s->to_dst_file);
1812 }
1813
1814 qemu_savevm_state_begin(s->to_dst_file, &s->params);
1815
1816 s->setup_time = qemu_clock_get_ms(QEMU_CLOCK_HOST) - setup_start;
1817 current_active_state = MIGRATION_STATUS_ACTIVE;
1818 migrate_set_state(&s->state, MIGRATION_STATUS_SETUP,
1819 MIGRATION_STATUS_ACTIVE);
1820
1821 trace_migration_thread_setup_complete();
1822
1823 while (s->state == MIGRATION_STATUS_ACTIVE ||
1824 s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) {
1825 int64_t current_time;
1826 uint64_t pending_size;
1827
1828 if (!qemu_file_rate_limit(s->to_dst_file)) {
1829 uint64_t pend_post, pend_nonpost;
1830
1831 qemu_savevm_state_pending(s->to_dst_file, max_size, &pend_nonpost,
1832 &pend_post);
1833 pending_size = pend_nonpost + pend_post;
1834 trace_migrate_pending(pending_size, max_size,
1835 pend_post, pend_nonpost);
1836 if (pending_size && pending_size >= max_size) {
1837 /* Still a significant amount to transfer */
1838
1839 if (migrate_postcopy_ram() &&
1840 s->state != MIGRATION_STATUS_POSTCOPY_ACTIVE &&
1841 pend_nonpost <= max_size &&
1842 atomic_read(&s->start_postcopy)) {
1843
1844 if (!postcopy_start(s, &old_vm_running)) {
1845 current_active_state = MIGRATION_STATUS_POSTCOPY_ACTIVE;
1846 entered_postcopy = true;
1847 }
1848
1849 continue;
1850 }
1851 /* Just another iteration step */
1852 qemu_savevm_state_iterate(s->to_dst_file, entered_postcopy);
1853 } else {
1854 trace_migration_thread_low_pending(pending_size);
1855 migration_completion(s, current_active_state,
1856 &old_vm_running, &start_time);
1857 break;
1858 }
1859 }
1860
1861 if (qemu_file_get_error(s->to_dst_file)) {
1862 migrate_set_state(&s->state, current_active_state,
1863 MIGRATION_STATUS_FAILED);
1864 trace_migration_thread_file_err();
1865 break;
1866 }
1867 current_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
1868 if (current_time >= initial_time + BUFFER_DELAY) {
1869 uint64_t transferred_bytes = qemu_ftell(s->to_dst_file) -
1870 initial_bytes;
1871 uint64_t time_spent = current_time - initial_time;
1872 double bandwidth = (double)transferred_bytes / time_spent;
1873 max_size = bandwidth * s->parameters.downtime_limit;
1874
1875 s->mbps = (((double) transferred_bytes * 8.0) /
1876 ((double) time_spent / 1000.0)) / 1000.0 / 1000.0;
1877
1878 trace_migrate_transferred(transferred_bytes, time_spent,
1879 bandwidth, max_size);
1880 /* if we haven't sent anything, we don't want to recalculate
1881 10000 is a small enough number for our purposes */
1882 if (s->dirty_bytes_rate && transferred_bytes > 10000) {
1883 s->expected_downtime = s->dirty_bytes_rate / bandwidth;
1884 }
1885
1886 qemu_file_reset_rate_limit(s->to_dst_file);
1887 initial_time = current_time;
1888 initial_bytes = qemu_ftell(s->to_dst_file);
1889 }
1890 if (qemu_file_rate_limit(s->to_dst_file)) {
1891 /* usleep expects microseconds */
1892 g_usleep((initial_time + BUFFER_DELAY - current_time)*1000);
1893 }
1894 }
1895
1896 trace_migration_thread_after_loop();
1897 /* If we enabled cpu throttling for auto-converge, turn it off. */
1898 cpu_throttle_stop();
1899 end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
1900
1901 qemu_mutex_lock_iothread();
1902 /*
1903 * The resource has been allocated by migration will be reused in COLO
1904 * process, so don't release them.
1905 */
1906 if (!enable_colo) {
1907 qemu_savevm_state_cleanup();
1908 }
1909 if (s->state == MIGRATION_STATUS_COMPLETED) {
1910 uint64_t transferred_bytes = qemu_ftell(s->to_dst_file);
1911 s->total_time = end_time - s->total_time;
1912 if (!entered_postcopy) {
1913 s->downtime = end_time - start_time;
1914 }
1915 if (s->total_time) {
1916 s->mbps = (((double) transferred_bytes * 8.0) /
1917 ((double) s->total_time)) / 1000;
1918 }
1919 runstate_set(RUN_STATE_POSTMIGRATE);
1920 } else {
1921 if (s->state == MIGRATION_STATUS_ACTIVE && enable_colo) {
1922 migrate_start_colo_process(s);
1923 qemu_savevm_state_cleanup();
1924 /*
1925 * Fixme: we will run VM in COLO no matter its old running state.
1926 * After exited COLO, we will keep running.
1927 */
1928 old_vm_running = true;
1929 }
1930 if (old_vm_running && !entered_postcopy) {
1931 vm_start();
1932 } else {
1933 if (runstate_check(RUN_STATE_FINISH_MIGRATE)) {
1934 runstate_set(RUN_STATE_POSTMIGRATE);
1935 }
1936 }
1937 }
1938 qemu_bh_schedule(s->cleanup_bh);
1939 qemu_mutex_unlock_iothread();
1940
1941 rcu_unregister_thread();
1942 return NULL;
1943 }
1944
1945 void migrate_fd_connect(MigrationState *s)
1946 {
1947 s->expected_downtime = s->parameters.downtime_limit;
1948 s->cleanup_bh = qemu_bh_new(migrate_fd_cleanup, s);
1949
1950 qemu_file_set_blocking(s->to_dst_file, true);
1951 qemu_file_set_rate_limit(s->to_dst_file,
1952 s->parameters.max_bandwidth / XFER_LIMIT_RATIO);
1953
1954 /* Notify before starting migration thread */
1955 notifier_list_notify(&migration_state_notifiers, s);
1956
1957 /*
1958 * Open the return path; currently for postcopy but other things might
1959 * also want it.
1960 */
1961 if (migrate_postcopy_ram()) {
1962 if (open_return_path_on_source(s)) {
1963 error_report("Unable to open return-path for postcopy");
1964 migrate_set_state(&s->state, MIGRATION_STATUS_SETUP,
1965 MIGRATION_STATUS_FAILED);
1966 migrate_fd_cleanup(s);
1967 return;
1968 }
1969 }
1970
1971 migrate_compress_threads_create();
1972 qemu_thread_create(&s->thread, "migration", migration_thread, s,
1973 QEMU_THREAD_JOINABLE);
1974 s->migration_thread_running = true;
1975 }
1976
1977 PostcopyState postcopy_state_get(void)
1978 {
1979 return atomic_mb_read(&incoming_postcopy_state);
1980 }
1981
1982 /* Set the state and return the old state */
1983 PostcopyState postcopy_state_set(PostcopyState new_state)
1984 {
1985 return atomic_xchg(&incoming_postcopy_state, new_state);
1986 }
1987