travis.yml: Update Travis to use Bionic and Focal instead of Xenial
[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/blocker.h"
21 #include "exec.h"
22 #include "fd.h"
23 #include "socket.h"
24 #include "sysemu/runstate.h"
25 #include "sysemu/sysemu.h"
26 #include "sysemu/cpu-throttle.h"
27 #include "rdma.h"
28 #include "ram.h"
29 #include "migration/global_state.h"
30 #include "migration/misc.h"
31 #include "migration.h"
32 #include "savevm.h"
33 #include "qemu-file-channel.h"
34 #include "qemu-file.h"
35 #include "migration/vmstate.h"
36 #include "block/block.h"
37 #include "qapi/error.h"
38 #include "qapi/clone-visitor.h"
39 #include "qapi/qapi-visit-migration.h"
40 #include "qapi/qapi-visit-sockets.h"
41 #include "qapi/qapi-commands-migration.h"
42 #include "qapi/qapi-events-migration.h"
43 #include "qapi/qmp/qerror.h"
44 #include "qapi/qmp/qnull.h"
45 #include "qemu/rcu.h"
46 #include "block.h"
47 #include "postcopy-ram.h"
48 #include "qemu/thread.h"
49 #include "trace.h"
50 #include "exec/target_page.h"
51 #include "io/channel-buffer.h"
52 #include "migration/colo.h"
53 #include "hw/boards.h"
54 #include "hw/qdev-properties.h"
55 #include "monitor/monitor.h"
56 #include "net/announce.h"
57 #include "qemu/queue.h"
58 #include "multifd.h"
59
60 #define MAX_THROTTLE (128 << 20) /* Migration transfer speed throttling */
61
62 /* Amount of time to allocate to each "chunk" of bandwidth-throttled
63 * data. */
64 #define BUFFER_DELAY 100
65 #define XFER_LIMIT_RATIO (1000 / BUFFER_DELAY)
66
67 /* Time in milliseconds we are allowed to stop the source,
68 * for sending the last part */
69 #define DEFAULT_MIGRATE_SET_DOWNTIME 300
70
71 /* Maximum migrate downtime set to 2000 seconds */
72 #define MAX_MIGRATE_DOWNTIME_SECONDS 2000
73 #define MAX_MIGRATE_DOWNTIME (MAX_MIGRATE_DOWNTIME_SECONDS * 1000)
74
75 /* Default compression thread count */
76 #define DEFAULT_MIGRATE_COMPRESS_THREAD_COUNT 8
77 /* Default decompression thread count, usually decompression is at
78 * least 4 times as fast as compression.*/
79 #define DEFAULT_MIGRATE_DECOMPRESS_THREAD_COUNT 2
80 /*0: means nocompress, 1: best speed, ... 9: best compress ratio */
81 #define DEFAULT_MIGRATE_COMPRESS_LEVEL 1
82 /* Define default autoconverge cpu throttle migration parameters */
83 #define DEFAULT_MIGRATE_THROTTLE_TRIGGER_THRESHOLD 50
84 #define DEFAULT_MIGRATE_CPU_THROTTLE_INITIAL 20
85 #define DEFAULT_MIGRATE_CPU_THROTTLE_INCREMENT 10
86 #define DEFAULT_MIGRATE_MAX_CPU_THROTTLE 99
87
88 /* Migration XBZRLE default cache size */
89 #define DEFAULT_MIGRATE_XBZRLE_CACHE_SIZE (64 * 1024 * 1024)
90
91 /* The delay time (in ms) between two COLO checkpoints */
92 #define DEFAULT_MIGRATE_X_CHECKPOINT_DELAY (200 * 100)
93 #define DEFAULT_MIGRATE_MULTIFD_CHANNELS 2
94 #define DEFAULT_MIGRATE_MULTIFD_COMPRESSION MULTIFD_COMPRESSION_NONE
95 /* 0: means nocompress, 1: best speed, ... 9: best compress ratio */
96 #define DEFAULT_MIGRATE_MULTIFD_ZLIB_LEVEL 1
97 /* 0: means nocompress, 1: best speed, ... 20: best compress ratio */
98 #define DEFAULT_MIGRATE_MULTIFD_ZSTD_LEVEL 1
99
100 /* Background transfer rate for postcopy, 0 means unlimited, note
101 * that page requests can still exceed this limit.
102 */
103 #define DEFAULT_MIGRATE_MAX_POSTCOPY_BANDWIDTH 0
104
105 /*
106 * Parameters for self_announce_delay giving a stream of RARP/ARP
107 * packets after migration.
108 */
109 #define DEFAULT_MIGRATE_ANNOUNCE_INITIAL 50
110 #define DEFAULT_MIGRATE_ANNOUNCE_MAX 550
111 #define DEFAULT_MIGRATE_ANNOUNCE_ROUNDS 5
112 #define DEFAULT_MIGRATE_ANNOUNCE_STEP 100
113
114 static NotifierList migration_state_notifiers =
115 NOTIFIER_LIST_INITIALIZER(migration_state_notifiers);
116
117 static bool deferred_incoming;
118
119 /* Messages sent on the return path from destination to source */
120 enum mig_rp_message_type {
121 MIG_RP_MSG_INVALID = 0, /* Must be 0 */
122 MIG_RP_MSG_SHUT, /* sibling will not send any more RP messages */
123 MIG_RP_MSG_PONG, /* Response to a PING; data (seq: be32 ) */
124
125 MIG_RP_MSG_REQ_PAGES_ID, /* data (start: be64, len: be32, id: string) */
126 MIG_RP_MSG_REQ_PAGES, /* data (start: be64, len: be32) */
127 MIG_RP_MSG_RECV_BITMAP, /* send recved_bitmap back to source */
128 MIG_RP_MSG_RESUME_ACK, /* tell source that we are ready to resume */
129
130 MIG_RP_MSG_MAX
131 };
132
133 /* When we add fault tolerance, we could have several
134 migrations at once. For now we don't need to add
135 dynamic creation of migration */
136
137 static MigrationState *current_migration;
138 static MigrationIncomingState *current_incoming;
139
140 static bool migration_object_check(MigrationState *ms, Error **errp);
141 static int migration_maybe_pause(MigrationState *s,
142 int *current_active_state,
143 int new_state);
144 static void migrate_fd_cancel(MigrationState *s);
145
146 void migration_object_init(void)
147 {
148 MachineState *ms = MACHINE(qdev_get_machine());
149 Error *err = NULL;
150
151 /* This can only be called once. */
152 assert(!current_migration);
153 current_migration = MIGRATION_OBJ(object_new(TYPE_MIGRATION));
154
155 /*
156 * Init the migrate incoming object as well no matter whether
157 * we'll use it or not.
158 */
159 assert(!current_incoming);
160 current_incoming = g_new0(MigrationIncomingState, 1);
161 current_incoming->state = MIGRATION_STATUS_NONE;
162 current_incoming->postcopy_remote_fds =
163 g_array_new(FALSE, TRUE, sizeof(struct PostCopyFD));
164 qemu_mutex_init(&current_incoming->rp_mutex);
165 qemu_event_init(&current_incoming->main_thread_load_event, false);
166 qemu_sem_init(&current_incoming->postcopy_pause_sem_dst, 0);
167 qemu_sem_init(&current_incoming->postcopy_pause_sem_fault, 0);
168
169 if (!migration_object_check(current_migration, &err)) {
170 error_report_err(err);
171 exit(1);
172 }
173
174 /*
175 * We cannot really do this in migration_instance_init() since at
176 * that time global properties are not yet applied, then this
177 * value will be definitely replaced by something else.
178 */
179 if (ms->enforce_config_section) {
180 current_migration->send_configuration = true;
181 }
182 }
183
184 void migration_shutdown(void)
185 {
186 /*
187 * Cancel the current migration - that will (eventually)
188 * stop the migration using this structure
189 */
190 migrate_fd_cancel(current_migration);
191 object_unref(OBJECT(current_migration));
192
193 /*
194 * Cancel outgoing migration of dirty bitmaps. It should
195 * at least unref used block nodes.
196 */
197 dirty_bitmap_mig_cancel_outgoing();
198
199 /*
200 * Cancel incoming migration of dirty bitmaps. Dirty bitmaps
201 * are non-critical data, and their loss never considered as
202 * something serious.
203 */
204 dirty_bitmap_mig_cancel_incoming();
205 }
206
207 /* For outgoing */
208 MigrationState *migrate_get_current(void)
209 {
210 /* This can only be called after the object created. */
211 assert(current_migration);
212 return current_migration;
213 }
214
215 MigrationIncomingState *migration_incoming_get_current(void)
216 {
217 assert(current_incoming);
218 return current_incoming;
219 }
220
221 void migration_incoming_state_destroy(void)
222 {
223 struct MigrationIncomingState *mis = migration_incoming_get_current();
224
225 if (mis->to_src_file) {
226 /* Tell source that we are done */
227 migrate_send_rp_shut(mis, qemu_file_get_error(mis->from_src_file) != 0);
228 qemu_fclose(mis->to_src_file);
229 mis->to_src_file = NULL;
230 }
231
232 if (mis->from_src_file) {
233 qemu_fclose(mis->from_src_file);
234 mis->from_src_file = NULL;
235 }
236 if (mis->postcopy_remote_fds) {
237 g_array_free(mis->postcopy_remote_fds, TRUE);
238 mis->postcopy_remote_fds = NULL;
239 }
240
241 qemu_event_reset(&mis->main_thread_load_event);
242
243 if (mis->socket_address_list) {
244 qapi_free_SocketAddressList(mis->socket_address_list);
245 mis->socket_address_list = NULL;
246 }
247 }
248
249 static void migrate_generate_event(int new_state)
250 {
251 if (migrate_use_events()) {
252 qapi_event_send_migration(new_state);
253 }
254 }
255
256 static bool migrate_late_block_activate(void)
257 {
258 MigrationState *s;
259
260 s = migrate_get_current();
261
262 return s->enabled_capabilities[
263 MIGRATION_CAPABILITY_LATE_BLOCK_ACTIVATE];
264 }
265
266 /*
267 * Called on -incoming with a defer: uri.
268 * The migration can be started later after any parameters have been
269 * changed.
270 */
271 static void deferred_incoming_migration(Error **errp)
272 {
273 if (deferred_incoming) {
274 error_setg(errp, "Incoming migration already deferred");
275 }
276 deferred_incoming = true;
277 }
278
279 /*
280 * Send a message on the return channel back to the source
281 * of the migration.
282 */
283 static int migrate_send_rp_message(MigrationIncomingState *mis,
284 enum mig_rp_message_type message_type,
285 uint16_t len, void *data)
286 {
287 int ret = 0;
288
289 trace_migrate_send_rp_message((int)message_type, len);
290 qemu_mutex_lock(&mis->rp_mutex);
291
292 /*
293 * It's possible that the file handle got lost due to network
294 * failures.
295 */
296 if (!mis->to_src_file) {
297 ret = -EIO;
298 goto error;
299 }
300
301 qemu_put_be16(mis->to_src_file, (unsigned int)message_type);
302 qemu_put_be16(mis->to_src_file, len);
303 qemu_put_buffer(mis->to_src_file, data, len);
304 qemu_fflush(mis->to_src_file);
305
306 /* It's possible that qemu file got error during sending */
307 ret = qemu_file_get_error(mis->to_src_file);
308
309 error:
310 qemu_mutex_unlock(&mis->rp_mutex);
311 return ret;
312 }
313
314 /* Request one page from the source VM at the given start address.
315 * rb: the RAMBlock to request the page in
316 * Start: Address offset within the RB
317 * Len: Length in bytes required - must be a multiple of pagesize
318 */
319 int migrate_send_rp_req_pages(MigrationIncomingState *mis, RAMBlock *rb,
320 ram_addr_t start)
321 {
322 uint8_t bufc[12 + 1 + 255]; /* start (8), len (4), rbname up to 256 */
323 size_t msglen = 12; /* start + len */
324 size_t len = qemu_ram_pagesize(rb);
325 enum mig_rp_message_type msg_type;
326 const char *rbname;
327 int rbname_len;
328
329 *(uint64_t *)bufc = cpu_to_be64((uint64_t)start);
330 *(uint32_t *)(bufc + 8) = cpu_to_be32((uint32_t)len);
331
332 /*
333 * We maintain the last ramblock that we requested for page. Note that we
334 * don't need locking because this function will only be called within the
335 * postcopy ram fault thread.
336 */
337 if (rb != mis->last_rb) {
338 mis->last_rb = rb;
339
340 rbname = qemu_ram_get_idstr(rb);
341 rbname_len = strlen(rbname);
342
343 assert(rbname_len < 256);
344
345 bufc[msglen++] = rbname_len;
346 memcpy(bufc + msglen, rbname, rbname_len);
347 msglen += rbname_len;
348 msg_type = MIG_RP_MSG_REQ_PAGES_ID;
349 } else {
350 msg_type = MIG_RP_MSG_REQ_PAGES;
351 }
352
353 return migrate_send_rp_message(mis, msg_type, msglen, bufc);
354 }
355
356 static bool migration_colo_enabled;
357 bool migration_incoming_colo_enabled(void)
358 {
359 return migration_colo_enabled;
360 }
361
362 void migration_incoming_disable_colo(void)
363 {
364 ram_block_discard_disable(false);
365 migration_colo_enabled = false;
366 }
367
368 int migration_incoming_enable_colo(void)
369 {
370 if (ram_block_discard_disable(true)) {
371 error_report("COLO: cannot disable RAM discard");
372 return -EBUSY;
373 }
374 migration_colo_enabled = true;
375 return 0;
376 }
377
378 void migrate_add_address(SocketAddress *address)
379 {
380 MigrationIncomingState *mis = migration_incoming_get_current();
381 SocketAddressList *addrs;
382
383 addrs = g_new0(SocketAddressList, 1);
384 addrs->next = mis->socket_address_list;
385 mis->socket_address_list = addrs;
386 addrs->value = QAPI_CLONE(SocketAddress, address);
387 }
388
389 void qemu_start_incoming_migration(const char *uri, Error **errp)
390 {
391 const char *p = NULL;
392
393 qapi_event_send_migration(MIGRATION_STATUS_SETUP);
394 if (!strcmp(uri, "defer")) {
395 deferred_incoming_migration(errp);
396 } else if (strstart(uri, "tcp:", &p) ||
397 strstart(uri, "unix:", NULL) ||
398 strstart(uri, "vsock:", NULL)) {
399 socket_start_incoming_migration(p ? p : uri, errp);
400 #ifdef CONFIG_RDMA
401 } else if (strstart(uri, "rdma:", &p)) {
402 rdma_start_incoming_migration(p, errp);
403 #endif
404 } else if (strstart(uri, "exec:", &p)) {
405 exec_start_incoming_migration(p, errp);
406 } else if (strstart(uri, "fd:", &p)) {
407 fd_start_incoming_migration(p, errp);
408 } else {
409 error_setg(errp, "unknown migration protocol: %s", uri);
410 }
411 }
412
413 static void process_incoming_migration_bh(void *opaque)
414 {
415 Error *local_err = NULL;
416 MigrationIncomingState *mis = opaque;
417
418 /* If capability late_block_activate is set:
419 * Only fire up the block code now if we're going to restart the
420 * VM, else 'cont' will do it.
421 * This causes file locking to happen; so we don't want it to happen
422 * unless we really are starting the VM.
423 */
424 if (!migrate_late_block_activate() ||
425 (autostart && (!global_state_received() ||
426 global_state_get_runstate() == RUN_STATE_RUNNING))) {
427 /* Make sure all file formats flush their mutable metadata.
428 * If we get an error here, just don't restart the VM yet. */
429 bdrv_invalidate_cache_all(&local_err);
430 if (local_err) {
431 error_report_err(local_err);
432 local_err = NULL;
433 autostart = false;
434 }
435 }
436
437 /*
438 * This must happen after all error conditions are dealt with and
439 * we're sure the VM is going to be running on this host.
440 */
441 qemu_announce_self(&mis->announce_timer, migrate_announce_params());
442
443 if (multifd_load_cleanup(&local_err) != 0) {
444 error_report_err(local_err);
445 autostart = false;
446 }
447 /* If global state section was not received or we are in running
448 state, we need to obey autostart. Any other state is set with
449 runstate_set. */
450
451 dirty_bitmap_mig_before_vm_start();
452
453 if (!global_state_received() ||
454 global_state_get_runstate() == RUN_STATE_RUNNING) {
455 if (autostart) {
456 vm_start();
457 } else {
458 runstate_set(RUN_STATE_PAUSED);
459 }
460 } else if (migration_incoming_colo_enabled()) {
461 migration_incoming_disable_colo();
462 vm_start();
463 } else {
464 runstate_set(global_state_get_runstate());
465 }
466 /*
467 * This must happen after any state changes since as soon as an external
468 * observer sees this event they might start to prod at the VM assuming
469 * it's ready to use.
470 */
471 migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
472 MIGRATION_STATUS_COMPLETED);
473 qemu_bh_delete(mis->bh);
474 migration_incoming_state_destroy();
475 }
476
477 static void process_incoming_migration_co(void *opaque)
478 {
479 MigrationIncomingState *mis = migration_incoming_get_current();
480 PostcopyState ps;
481 int ret;
482 Error *local_err = NULL;
483
484 assert(mis->from_src_file);
485 mis->migration_incoming_co = qemu_coroutine_self();
486 mis->largest_page_size = qemu_ram_pagesize_largest();
487 postcopy_state_set(POSTCOPY_INCOMING_NONE);
488 migrate_set_state(&mis->state, MIGRATION_STATUS_NONE,
489 MIGRATION_STATUS_ACTIVE);
490 ret = qemu_loadvm_state(mis->from_src_file);
491
492 ps = postcopy_state_get();
493 trace_process_incoming_migration_co_end(ret, ps);
494 if (ps != POSTCOPY_INCOMING_NONE) {
495 if (ps == POSTCOPY_INCOMING_ADVISE) {
496 /*
497 * Where a migration had postcopy enabled (and thus went to advise)
498 * but managed to complete within the precopy period, we can use
499 * the normal exit.
500 */
501 postcopy_ram_incoming_cleanup(mis);
502 } else if (ret >= 0) {
503 /*
504 * Postcopy was started, cleanup should happen at the end of the
505 * postcopy thread.
506 */
507 trace_process_incoming_migration_co_postcopy_end_main();
508 return;
509 }
510 /* Else if something went wrong then just fall out of the normal exit */
511 }
512
513 /* we get COLO info, and know if we are in COLO mode */
514 if (!ret && migration_incoming_colo_enabled()) {
515 /* Make sure all file formats flush their mutable metadata */
516 bdrv_invalidate_cache_all(&local_err);
517 if (local_err) {
518 error_report_err(local_err);
519 goto fail;
520 }
521
522 qemu_thread_create(&mis->colo_incoming_thread, "COLO incoming",
523 colo_process_incoming_thread, mis, QEMU_THREAD_JOINABLE);
524 mis->have_colo_incoming_thread = true;
525 qemu_coroutine_yield();
526
527 /* Wait checkpoint incoming thread exit before free resource */
528 qemu_thread_join(&mis->colo_incoming_thread);
529 /* We hold the global iothread lock, so it is safe here */
530 colo_release_ram_cache();
531 }
532
533 if (ret < 0) {
534 error_report("load of migration failed: %s", strerror(-ret));
535 goto fail;
536 }
537 mis->bh = qemu_bh_new(process_incoming_migration_bh, mis);
538 qemu_bh_schedule(mis->bh);
539 mis->migration_incoming_co = NULL;
540 return;
541 fail:
542 local_err = NULL;
543 migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
544 MIGRATION_STATUS_FAILED);
545 qemu_fclose(mis->from_src_file);
546 if (multifd_load_cleanup(&local_err) != 0) {
547 error_report_err(local_err);
548 }
549 exit(EXIT_FAILURE);
550 }
551
552 /**
553 * @migration_incoming_setup: Setup incoming migration
554 *
555 * Returns 0 for no error or 1 for error
556 *
557 * @f: file for main migration channel
558 * @errp: where to put errors
559 */
560 static int migration_incoming_setup(QEMUFile *f, Error **errp)
561 {
562 MigrationIncomingState *mis = migration_incoming_get_current();
563 Error *local_err = NULL;
564
565 if (multifd_load_setup(&local_err) != 0) {
566 /* We haven't been able to create multifd threads
567 nothing better to do */
568 error_report_err(local_err);
569 exit(EXIT_FAILURE);
570 }
571
572 if (!mis->from_src_file) {
573 mis->from_src_file = f;
574 }
575 qemu_file_set_blocking(f, false);
576 return 0;
577 }
578
579 void migration_incoming_process(void)
580 {
581 Coroutine *co = qemu_coroutine_create(process_incoming_migration_co, NULL);
582 qemu_coroutine_enter(co);
583 }
584
585 /* Returns true if recovered from a paused migration, otherwise false */
586 static bool postcopy_try_recover(QEMUFile *f)
587 {
588 MigrationIncomingState *mis = migration_incoming_get_current();
589
590 if (mis->state == MIGRATION_STATUS_POSTCOPY_PAUSED) {
591 /* Resumed from a paused postcopy migration */
592
593 mis->from_src_file = f;
594 /* Postcopy has standalone thread to do vm load */
595 qemu_file_set_blocking(f, true);
596
597 /* Re-configure the return path */
598 mis->to_src_file = qemu_file_get_return_path(f);
599
600 migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_PAUSED,
601 MIGRATION_STATUS_POSTCOPY_RECOVER);
602
603 /*
604 * Here, we only wake up the main loading thread (while the
605 * fault thread will still be waiting), so that we can receive
606 * commands from source now, and answer it if needed. The
607 * fault thread will be woken up afterwards until we are sure
608 * that source is ready to reply to page requests.
609 */
610 qemu_sem_post(&mis->postcopy_pause_sem_dst);
611 return true;
612 }
613
614 return false;
615 }
616
617 void migration_fd_process_incoming(QEMUFile *f, Error **errp)
618 {
619 Error *local_err = NULL;
620
621 if (postcopy_try_recover(f)) {
622 return;
623 }
624
625 if (migration_incoming_setup(f, &local_err)) {
626 if (local_err) {
627 error_propagate(errp, local_err);
628 }
629 return;
630 }
631 migration_incoming_process();
632 }
633
634 void migration_ioc_process_incoming(QIOChannel *ioc, Error **errp)
635 {
636 MigrationIncomingState *mis = migration_incoming_get_current();
637 Error *local_err = NULL;
638 bool start_migration;
639
640 if (!mis->from_src_file) {
641 /* The first connection (multifd may have multiple) */
642 QEMUFile *f = qemu_fopen_channel_input(ioc);
643
644 /* If it's a recovery, we're done */
645 if (postcopy_try_recover(f)) {
646 return;
647 }
648
649 if (migration_incoming_setup(f, &local_err)) {
650 if (local_err) {
651 error_propagate(errp, local_err);
652 }
653 return;
654 }
655
656 /*
657 * Common migration only needs one channel, so we can start
658 * right now. Multifd needs more than one channel, we wait.
659 */
660 start_migration = !migrate_use_multifd();
661 } else {
662 /* Multiple connections */
663 assert(migrate_use_multifd());
664 start_migration = multifd_recv_new_channel(ioc, &local_err);
665 if (local_err) {
666 error_propagate(errp, local_err);
667 return;
668 }
669 }
670
671 if (start_migration) {
672 migration_incoming_process();
673 }
674 }
675
676 /**
677 * @migration_has_all_channels: We have received all channels that we need
678 *
679 * Returns true when we have got connections to all the channels that
680 * we need for migration.
681 */
682 bool migration_has_all_channels(void)
683 {
684 MigrationIncomingState *mis = migration_incoming_get_current();
685 bool all_channels;
686
687 all_channels = multifd_recv_all_channels_created();
688
689 return all_channels && mis->from_src_file != NULL;
690 }
691
692 /*
693 * Send a 'SHUT' message on the return channel with the given value
694 * to indicate that we've finished with the RP. Non-0 value indicates
695 * error.
696 */
697 void migrate_send_rp_shut(MigrationIncomingState *mis,
698 uint32_t value)
699 {
700 uint32_t buf;
701
702 buf = cpu_to_be32(value);
703 migrate_send_rp_message(mis, MIG_RP_MSG_SHUT, sizeof(buf), &buf);
704 }
705
706 /*
707 * Send a 'PONG' message on the return channel with the given value
708 * (normally in response to a 'PING')
709 */
710 void migrate_send_rp_pong(MigrationIncomingState *mis,
711 uint32_t value)
712 {
713 uint32_t buf;
714
715 buf = cpu_to_be32(value);
716 migrate_send_rp_message(mis, MIG_RP_MSG_PONG, sizeof(buf), &buf);
717 }
718
719 void migrate_send_rp_recv_bitmap(MigrationIncomingState *mis,
720 char *block_name)
721 {
722 char buf[512];
723 int len;
724 int64_t res;
725
726 /*
727 * First, we send the header part. It contains only the len of
728 * idstr, and the idstr itself.
729 */
730 len = strlen(block_name);
731 buf[0] = len;
732 memcpy(buf + 1, block_name, len);
733
734 if (mis->state != MIGRATION_STATUS_POSTCOPY_RECOVER) {
735 error_report("%s: MSG_RP_RECV_BITMAP only used for recovery",
736 __func__);
737 return;
738 }
739
740 migrate_send_rp_message(mis, MIG_RP_MSG_RECV_BITMAP, len + 1, buf);
741
742 /*
743 * Next, we dump the received bitmap to the stream.
744 *
745 * TODO: currently we are safe since we are the only one that is
746 * using the to_src_file handle (fault thread is still paused),
747 * and it's ok even not taking the mutex. However the best way is
748 * to take the lock before sending the message header, and release
749 * the lock after sending the bitmap.
750 */
751 qemu_mutex_lock(&mis->rp_mutex);
752 res = ramblock_recv_bitmap_send(mis->to_src_file, block_name);
753 qemu_mutex_unlock(&mis->rp_mutex);
754
755 trace_migrate_send_rp_recv_bitmap(block_name, res);
756 }
757
758 void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value)
759 {
760 uint32_t buf;
761
762 buf = cpu_to_be32(value);
763 migrate_send_rp_message(mis, MIG_RP_MSG_RESUME_ACK, sizeof(buf), &buf);
764 }
765
766 MigrationCapabilityStatusList *qmp_query_migrate_capabilities(Error **errp)
767 {
768 MigrationCapabilityStatusList *head = NULL;
769 MigrationCapabilityStatusList *caps;
770 MigrationState *s = migrate_get_current();
771 int i;
772
773 caps = NULL; /* silence compiler warning */
774 for (i = 0; i < MIGRATION_CAPABILITY__MAX; i++) {
775 #ifndef CONFIG_LIVE_BLOCK_MIGRATION
776 if (i == MIGRATION_CAPABILITY_BLOCK) {
777 continue;
778 }
779 #endif
780 if (head == NULL) {
781 head = g_malloc0(sizeof(*caps));
782 caps = head;
783 } else {
784 caps->next = g_malloc0(sizeof(*caps));
785 caps = caps->next;
786 }
787 caps->value =
788 g_malloc(sizeof(*caps->value));
789 caps->value->capability = i;
790 caps->value->state = s->enabled_capabilities[i];
791 }
792
793 return head;
794 }
795
796 MigrationParameters *qmp_query_migrate_parameters(Error **errp)
797 {
798 MigrationParameters *params;
799 MigrationState *s = migrate_get_current();
800
801 /* TODO use QAPI_CLONE() instead of duplicating it inline */
802 params = g_malloc0(sizeof(*params));
803 params->has_compress_level = true;
804 params->compress_level = s->parameters.compress_level;
805 params->has_compress_threads = true;
806 params->compress_threads = s->parameters.compress_threads;
807 params->has_compress_wait_thread = true;
808 params->compress_wait_thread = s->parameters.compress_wait_thread;
809 params->has_decompress_threads = true;
810 params->decompress_threads = s->parameters.decompress_threads;
811 params->has_throttle_trigger_threshold = true;
812 params->throttle_trigger_threshold = s->parameters.throttle_trigger_threshold;
813 params->has_cpu_throttle_initial = true;
814 params->cpu_throttle_initial = s->parameters.cpu_throttle_initial;
815 params->has_cpu_throttle_increment = true;
816 params->cpu_throttle_increment = s->parameters.cpu_throttle_increment;
817 params->has_cpu_throttle_tailslow = true;
818 params->cpu_throttle_tailslow = s->parameters.cpu_throttle_tailslow;
819 params->has_tls_creds = true;
820 params->tls_creds = g_strdup(s->parameters.tls_creds);
821 params->has_tls_hostname = true;
822 params->tls_hostname = g_strdup(s->parameters.tls_hostname);
823 params->has_tls_authz = true;
824 params->tls_authz = g_strdup(s->parameters.tls_authz ?
825 s->parameters.tls_authz : "");
826 params->has_max_bandwidth = true;
827 params->max_bandwidth = s->parameters.max_bandwidth;
828 params->has_downtime_limit = true;
829 params->downtime_limit = s->parameters.downtime_limit;
830 params->has_x_checkpoint_delay = true;
831 params->x_checkpoint_delay = s->parameters.x_checkpoint_delay;
832 params->has_block_incremental = true;
833 params->block_incremental = s->parameters.block_incremental;
834 params->has_multifd_channels = true;
835 params->multifd_channels = s->parameters.multifd_channels;
836 params->has_multifd_compression = true;
837 params->multifd_compression = s->parameters.multifd_compression;
838 params->has_multifd_zlib_level = true;
839 params->multifd_zlib_level = s->parameters.multifd_zlib_level;
840 params->has_multifd_zstd_level = true;
841 params->multifd_zstd_level = s->parameters.multifd_zstd_level;
842 params->has_xbzrle_cache_size = true;
843 params->xbzrle_cache_size = s->parameters.xbzrle_cache_size;
844 params->has_max_postcopy_bandwidth = true;
845 params->max_postcopy_bandwidth = s->parameters.max_postcopy_bandwidth;
846 params->has_max_cpu_throttle = true;
847 params->max_cpu_throttle = s->parameters.max_cpu_throttle;
848 params->has_announce_initial = true;
849 params->announce_initial = s->parameters.announce_initial;
850 params->has_announce_max = true;
851 params->announce_max = s->parameters.announce_max;
852 params->has_announce_rounds = true;
853 params->announce_rounds = s->parameters.announce_rounds;
854 params->has_announce_step = true;
855 params->announce_step = s->parameters.announce_step;
856
857 if (s->parameters.has_block_bitmap_mapping) {
858 params->has_block_bitmap_mapping = true;
859 params->block_bitmap_mapping =
860 QAPI_CLONE(BitmapMigrationNodeAliasList,
861 s->parameters.block_bitmap_mapping);
862 }
863
864 return params;
865 }
866
867 AnnounceParameters *migrate_announce_params(void)
868 {
869 static AnnounceParameters ap;
870
871 MigrationState *s = migrate_get_current();
872
873 ap.initial = s->parameters.announce_initial;
874 ap.max = s->parameters.announce_max;
875 ap.rounds = s->parameters.announce_rounds;
876 ap.step = s->parameters.announce_step;
877
878 return &ap;
879 }
880
881 /*
882 * Return true if we're already in the middle of a migration
883 * (i.e. any of the active or setup states)
884 */
885 bool migration_is_setup_or_active(int state)
886 {
887 switch (state) {
888 case MIGRATION_STATUS_ACTIVE:
889 case MIGRATION_STATUS_POSTCOPY_ACTIVE:
890 case MIGRATION_STATUS_POSTCOPY_PAUSED:
891 case MIGRATION_STATUS_POSTCOPY_RECOVER:
892 case MIGRATION_STATUS_SETUP:
893 case MIGRATION_STATUS_PRE_SWITCHOVER:
894 case MIGRATION_STATUS_DEVICE:
895 case MIGRATION_STATUS_WAIT_UNPLUG:
896 case MIGRATION_STATUS_COLO:
897 return true;
898
899 default:
900 return false;
901
902 }
903 }
904
905 bool migration_is_running(int state)
906 {
907 switch (state) {
908 case MIGRATION_STATUS_ACTIVE:
909 case MIGRATION_STATUS_POSTCOPY_ACTIVE:
910 case MIGRATION_STATUS_POSTCOPY_PAUSED:
911 case MIGRATION_STATUS_POSTCOPY_RECOVER:
912 case MIGRATION_STATUS_SETUP:
913 case MIGRATION_STATUS_PRE_SWITCHOVER:
914 case MIGRATION_STATUS_DEVICE:
915 case MIGRATION_STATUS_WAIT_UNPLUG:
916 case MIGRATION_STATUS_CANCELLING:
917 return true;
918
919 default:
920 return false;
921
922 }
923 }
924
925 static void populate_time_info(MigrationInfo *info, MigrationState *s)
926 {
927 info->has_status = true;
928 info->has_setup_time = true;
929 info->setup_time = s->setup_time;
930 if (s->state == MIGRATION_STATUS_COMPLETED) {
931 info->has_total_time = true;
932 info->total_time = s->total_time;
933 info->has_downtime = true;
934 info->downtime = s->downtime;
935 } else {
936 info->has_total_time = true;
937 info->total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) -
938 s->start_time;
939 info->has_expected_downtime = true;
940 info->expected_downtime = s->expected_downtime;
941 }
942 }
943
944 static void populate_ram_info(MigrationInfo *info, MigrationState *s)
945 {
946 info->has_ram = true;
947 info->ram = g_malloc0(sizeof(*info->ram));
948 info->ram->transferred = ram_counters.transferred;
949 info->ram->total = ram_bytes_total();
950 info->ram->duplicate = ram_counters.duplicate;
951 /* legacy value. It is not used anymore */
952 info->ram->skipped = 0;
953 info->ram->normal = ram_counters.normal;
954 info->ram->normal_bytes = ram_counters.normal *
955 qemu_target_page_size();
956 info->ram->mbps = s->mbps;
957 info->ram->dirty_sync_count = ram_counters.dirty_sync_count;
958 info->ram->postcopy_requests = ram_counters.postcopy_requests;
959 info->ram->page_size = qemu_target_page_size();
960 info->ram->multifd_bytes = ram_counters.multifd_bytes;
961 info->ram->pages_per_second = s->pages_per_second;
962
963 if (migrate_use_xbzrle()) {
964 info->has_xbzrle_cache = true;
965 info->xbzrle_cache = g_malloc0(sizeof(*info->xbzrle_cache));
966 info->xbzrle_cache->cache_size = migrate_xbzrle_cache_size();
967 info->xbzrle_cache->bytes = xbzrle_counters.bytes;
968 info->xbzrle_cache->pages = xbzrle_counters.pages;
969 info->xbzrle_cache->cache_miss = xbzrle_counters.cache_miss;
970 info->xbzrle_cache->cache_miss_rate = xbzrle_counters.cache_miss_rate;
971 info->xbzrle_cache->encoding_rate = xbzrle_counters.encoding_rate;
972 info->xbzrle_cache->overflow = xbzrle_counters.overflow;
973 }
974
975 if (migrate_use_compression()) {
976 info->has_compression = true;
977 info->compression = g_malloc0(sizeof(*info->compression));
978 info->compression->pages = compression_counters.pages;
979 info->compression->busy = compression_counters.busy;
980 info->compression->busy_rate = compression_counters.busy_rate;
981 info->compression->compressed_size =
982 compression_counters.compressed_size;
983 info->compression->compression_rate =
984 compression_counters.compression_rate;
985 }
986
987 if (cpu_throttle_active()) {
988 info->has_cpu_throttle_percentage = true;
989 info->cpu_throttle_percentage = cpu_throttle_get_percentage();
990 }
991
992 if (s->state != MIGRATION_STATUS_COMPLETED) {
993 info->ram->remaining = ram_bytes_remaining();
994 info->ram->dirty_pages_rate = ram_counters.dirty_pages_rate;
995 }
996 }
997
998 static void populate_disk_info(MigrationInfo *info)
999 {
1000 if (blk_mig_active()) {
1001 info->has_disk = true;
1002 info->disk = g_malloc0(sizeof(*info->disk));
1003 info->disk->transferred = blk_mig_bytes_transferred();
1004 info->disk->remaining = blk_mig_bytes_remaining();
1005 info->disk->total = blk_mig_bytes_total();
1006 }
1007 }
1008
1009 static void fill_source_migration_info(MigrationInfo *info)
1010 {
1011 MigrationState *s = migrate_get_current();
1012
1013 switch (s->state) {
1014 case MIGRATION_STATUS_NONE:
1015 /* no migration has happened ever */
1016 /* do not overwrite destination migration status */
1017 return;
1018 case MIGRATION_STATUS_SETUP:
1019 info->has_status = true;
1020 info->has_total_time = false;
1021 break;
1022 case MIGRATION_STATUS_ACTIVE:
1023 case MIGRATION_STATUS_CANCELLING:
1024 case MIGRATION_STATUS_POSTCOPY_ACTIVE:
1025 case MIGRATION_STATUS_PRE_SWITCHOVER:
1026 case MIGRATION_STATUS_DEVICE:
1027 case MIGRATION_STATUS_POSTCOPY_PAUSED:
1028 case MIGRATION_STATUS_POSTCOPY_RECOVER:
1029 /* TODO add some postcopy stats */
1030 populate_time_info(info, s);
1031 populate_ram_info(info, s);
1032 populate_disk_info(info);
1033 break;
1034 case MIGRATION_STATUS_COLO:
1035 info->has_status = true;
1036 /* TODO: display COLO specific information (checkpoint info etc.) */
1037 break;
1038 case MIGRATION_STATUS_COMPLETED:
1039 populate_time_info(info, s);
1040 populate_ram_info(info, s);
1041 break;
1042 case MIGRATION_STATUS_FAILED:
1043 info->has_status = true;
1044 if (s->error) {
1045 info->has_error_desc = true;
1046 info->error_desc = g_strdup(error_get_pretty(s->error));
1047 }
1048 break;
1049 case MIGRATION_STATUS_CANCELLED:
1050 info->has_status = true;
1051 break;
1052 case MIGRATION_STATUS_WAIT_UNPLUG:
1053 info->has_status = true;
1054 break;
1055 }
1056 info->status = s->state;
1057 }
1058
1059 /**
1060 * @migration_caps_check - check capability validity
1061 *
1062 * @cap_list: old capability list, array of bool
1063 * @params: new capabilities to be applied soon
1064 * @errp: set *errp if the check failed, with reason
1065 *
1066 * Returns true if check passed, otherwise false.
1067 */
1068 static bool migrate_caps_check(bool *cap_list,
1069 MigrationCapabilityStatusList *params,
1070 Error **errp)
1071 {
1072 MigrationCapabilityStatusList *cap;
1073 bool old_postcopy_cap;
1074 MigrationIncomingState *mis = migration_incoming_get_current();
1075
1076 old_postcopy_cap = cap_list[MIGRATION_CAPABILITY_POSTCOPY_RAM];
1077
1078 for (cap = params; cap; cap = cap->next) {
1079 cap_list[cap->value->capability] = cap->value->state;
1080 }
1081
1082 #ifndef CONFIG_LIVE_BLOCK_MIGRATION
1083 if (cap_list[MIGRATION_CAPABILITY_BLOCK]) {
1084 error_setg(errp, "QEMU compiled without old-style (blk/-b, inc/-i) "
1085 "block migration");
1086 error_append_hint(errp, "Use drive_mirror+NBD instead.\n");
1087 return false;
1088 }
1089 #endif
1090
1091 #ifndef CONFIG_REPLICATION
1092 if (cap_list[MIGRATION_CAPABILITY_X_COLO]) {
1093 error_setg(errp, "QEMU compiled without replication module"
1094 " can't enable COLO");
1095 error_append_hint(errp, "Please enable replication before COLO.\n");
1096 return false;
1097 }
1098 #endif
1099
1100 if (cap_list[MIGRATION_CAPABILITY_POSTCOPY_RAM]) {
1101 /* This check is reasonably expensive, so only when it's being
1102 * set the first time, also it's only the destination that needs
1103 * special support.
1104 */
1105 if (!old_postcopy_cap && runstate_check(RUN_STATE_INMIGRATE) &&
1106 !postcopy_ram_supported_by_host(mis)) {
1107 /* postcopy_ram_supported_by_host will have emitted a more
1108 * detailed message
1109 */
1110 error_setg(errp, "Postcopy is not supported");
1111 return false;
1112 }
1113
1114 if (cap_list[MIGRATION_CAPABILITY_X_IGNORE_SHARED]) {
1115 error_setg(errp, "Postcopy is not compatible with ignore-shared");
1116 return false;
1117 }
1118 }
1119
1120 return true;
1121 }
1122
1123 static void fill_destination_migration_info(MigrationInfo *info)
1124 {
1125 MigrationIncomingState *mis = migration_incoming_get_current();
1126
1127 if (mis->socket_address_list) {
1128 info->has_socket_address = true;
1129 info->socket_address =
1130 QAPI_CLONE(SocketAddressList, mis->socket_address_list);
1131 }
1132
1133 switch (mis->state) {
1134 case MIGRATION_STATUS_NONE:
1135 return;
1136 case MIGRATION_STATUS_SETUP:
1137 case MIGRATION_STATUS_CANCELLING:
1138 case MIGRATION_STATUS_CANCELLED:
1139 case MIGRATION_STATUS_ACTIVE:
1140 case MIGRATION_STATUS_POSTCOPY_ACTIVE:
1141 case MIGRATION_STATUS_POSTCOPY_PAUSED:
1142 case MIGRATION_STATUS_POSTCOPY_RECOVER:
1143 case MIGRATION_STATUS_FAILED:
1144 case MIGRATION_STATUS_COLO:
1145 info->has_status = true;
1146 break;
1147 case MIGRATION_STATUS_COMPLETED:
1148 info->has_status = true;
1149 fill_destination_postcopy_migration_info(info);
1150 break;
1151 }
1152 info->status = mis->state;
1153 }
1154
1155 MigrationInfo *qmp_query_migrate(Error **errp)
1156 {
1157 MigrationInfo *info = g_malloc0(sizeof(*info));
1158
1159 fill_destination_migration_info(info);
1160 fill_source_migration_info(info);
1161
1162 return info;
1163 }
1164
1165 void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params,
1166 Error **errp)
1167 {
1168 MigrationState *s = migrate_get_current();
1169 MigrationCapabilityStatusList *cap;
1170 bool cap_list[MIGRATION_CAPABILITY__MAX];
1171
1172 if (migration_is_running(s->state)) {
1173 error_setg(errp, QERR_MIGRATION_ACTIVE);
1174 return;
1175 }
1176
1177 memcpy(cap_list, s->enabled_capabilities, sizeof(cap_list));
1178 if (!migrate_caps_check(cap_list, params, errp)) {
1179 return;
1180 }
1181
1182 for (cap = params; cap; cap = cap->next) {
1183 s->enabled_capabilities[cap->value->capability] = cap->value->state;
1184 }
1185 }
1186
1187 /*
1188 * Check whether the parameters are valid. Error will be put into errp
1189 * (if provided). Return true if valid, otherwise false.
1190 */
1191 static bool migrate_params_check(MigrationParameters *params, Error **errp)
1192 {
1193 if (params->has_compress_level &&
1194 (params->compress_level > 9)) {
1195 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "compress_level",
1196 "is invalid, it should be in the range of 0 to 9");
1197 return false;
1198 }
1199
1200 if (params->has_compress_threads && (params->compress_threads < 1)) {
1201 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1202 "compress_threads",
1203 "is invalid, it should be in the range of 1 to 255");
1204 return false;
1205 }
1206
1207 if (params->has_decompress_threads && (params->decompress_threads < 1)) {
1208 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1209 "decompress_threads",
1210 "is invalid, it should be in the range of 1 to 255");
1211 return false;
1212 }
1213
1214 if (params->has_throttle_trigger_threshold &&
1215 (params->throttle_trigger_threshold < 1 ||
1216 params->throttle_trigger_threshold > 100)) {
1217 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1218 "throttle_trigger_threshold",
1219 "an integer in the range of 1 to 100");
1220 return false;
1221 }
1222
1223 if (params->has_cpu_throttle_initial &&
1224 (params->cpu_throttle_initial < 1 ||
1225 params->cpu_throttle_initial > 99)) {
1226 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1227 "cpu_throttle_initial",
1228 "an integer in the range of 1 to 99");
1229 return false;
1230 }
1231
1232 if (params->has_cpu_throttle_increment &&
1233 (params->cpu_throttle_increment < 1 ||
1234 params->cpu_throttle_increment > 99)) {
1235 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1236 "cpu_throttle_increment",
1237 "an integer in the range of 1 to 99");
1238 return false;
1239 }
1240
1241 if (params->has_max_bandwidth && (params->max_bandwidth > SIZE_MAX)) {
1242 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1243 "max_bandwidth",
1244 "an integer in the range of 0 to "stringify(SIZE_MAX)
1245 " bytes/second");
1246 return false;
1247 }
1248
1249 if (params->has_downtime_limit &&
1250 (params->downtime_limit > MAX_MIGRATE_DOWNTIME)) {
1251 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1252 "downtime_limit",
1253 "an integer in the range of 0 to "
1254 stringify(MAX_MIGRATE_DOWNTIME)" ms");
1255 return false;
1256 }
1257
1258 /* x_checkpoint_delay is now always positive */
1259
1260 if (params->has_multifd_channels && (params->multifd_channels < 1)) {
1261 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1262 "multifd_channels",
1263 "is invalid, it should be in the range of 1 to 255");
1264 return false;
1265 }
1266
1267 if (params->has_multifd_zlib_level &&
1268 (params->multifd_zlib_level > 9)) {
1269 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "multifd_zlib_level",
1270 "is invalid, it should be in the range of 0 to 9");
1271 return false;
1272 }
1273
1274 if (params->has_multifd_zstd_level &&
1275 (params->multifd_zstd_level > 20)) {
1276 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "multifd_zstd_level",
1277 "is invalid, it should be in the range of 0 to 20");
1278 return false;
1279 }
1280
1281 if (params->has_xbzrle_cache_size &&
1282 (params->xbzrle_cache_size < qemu_target_page_size() ||
1283 !is_power_of_2(params->xbzrle_cache_size))) {
1284 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1285 "xbzrle_cache_size",
1286 "is invalid, it should be bigger than target page size"
1287 " and a power of 2");
1288 return false;
1289 }
1290
1291 if (params->has_max_cpu_throttle &&
1292 (params->max_cpu_throttle < params->cpu_throttle_initial ||
1293 params->max_cpu_throttle > 99)) {
1294 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1295 "max_cpu_throttle",
1296 "an integer in the range of cpu_throttle_initial to 99");
1297 return false;
1298 }
1299
1300 if (params->has_announce_initial &&
1301 params->announce_initial > 100000) {
1302 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1303 "announce_initial",
1304 "is invalid, it must be less than 100000 ms");
1305 return false;
1306 }
1307 if (params->has_announce_max &&
1308 params->announce_max > 100000) {
1309 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1310 "announce_max",
1311 "is invalid, it must be less than 100000 ms");
1312 return false;
1313 }
1314 if (params->has_announce_rounds &&
1315 params->announce_rounds > 1000) {
1316 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1317 "announce_rounds",
1318 "is invalid, it must be in the range of 0 to 1000");
1319 return false;
1320 }
1321 if (params->has_announce_step &&
1322 (params->announce_step < 1 ||
1323 params->announce_step > 10000)) {
1324 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1325 "announce_step",
1326 "is invalid, it must be in the range of 1 to 10000 ms");
1327 return false;
1328 }
1329
1330 if (params->has_block_bitmap_mapping &&
1331 !check_dirty_bitmap_mig_alias_map(params->block_bitmap_mapping, errp)) {
1332 error_prepend(errp, "Invalid mapping given for block-bitmap-mapping: ");
1333 return false;
1334 }
1335
1336 return true;
1337 }
1338
1339 static void migrate_params_test_apply(MigrateSetParameters *params,
1340 MigrationParameters *dest)
1341 {
1342 *dest = migrate_get_current()->parameters;
1343
1344 /* TODO use QAPI_CLONE() instead of duplicating it inline */
1345
1346 if (params->has_compress_level) {
1347 dest->compress_level = params->compress_level;
1348 }
1349
1350 if (params->has_compress_threads) {
1351 dest->compress_threads = params->compress_threads;
1352 }
1353
1354 if (params->has_compress_wait_thread) {
1355 dest->compress_wait_thread = params->compress_wait_thread;
1356 }
1357
1358 if (params->has_decompress_threads) {
1359 dest->decompress_threads = params->decompress_threads;
1360 }
1361
1362 if (params->has_throttle_trigger_threshold) {
1363 dest->throttle_trigger_threshold = params->throttle_trigger_threshold;
1364 }
1365
1366 if (params->has_cpu_throttle_initial) {
1367 dest->cpu_throttle_initial = params->cpu_throttle_initial;
1368 }
1369
1370 if (params->has_cpu_throttle_increment) {
1371 dest->cpu_throttle_increment = params->cpu_throttle_increment;
1372 }
1373
1374 if (params->has_cpu_throttle_tailslow) {
1375 dest->cpu_throttle_tailslow = params->cpu_throttle_tailslow;
1376 }
1377
1378 if (params->has_tls_creds) {
1379 assert(params->tls_creds->type == QTYPE_QSTRING);
1380 dest->tls_creds = params->tls_creds->u.s;
1381 }
1382
1383 if (params->has_tls_hostname) {
1384 assert(params->tls_hostname->type == QTYPE_QSTRING);
1385 dest->tls_hostname = params->tls_hostname->u.s;
1386 }
1387
1388 if (params->has_max_bandwidth) {
1389 dest->max_bandwidth = params->max_bandwidth;
1390 }
1391
1392 if (params->has_downtime_limit) {
1393 dest->downtime_limit = params->downtime_limit;
1394 }
1395
1396 if (params->has_x_checkpoint_delay) {
1397 dest->x_checkpoint_delay = params->x_checkpoint_delay;
1398 }
1399
1400 if (params->has_block_incremental) {
1401 dest->block_incremental = params->block_incremental;
1402 }
1403 if (params->has_multifd_channels) {
1404 dest->multifd_channels = params->multifd_channels;
1405 }
1406 if (params->has_multifd_compression) {
1407 dest->multifd_compression = params->multifd_compression;
1408 }
1409 if (params->has_xbzrle_cache_size) {
1410 dest->xbzrle_cache_size = params->xbzrle_cache_size;
1411 }
1412 if (params->has_max_postcopy_bandwidth) {
1413 dest->max_postcopy_bandwidth = params->max_postcopy_bandwidth;
1414 }
1415 if (params->has_max_cpu_throttle) {
1416 dest->max_cpu_throttle = params->max_cpu_throttle;
1417 }
1418 if (params->has_announce_initial) {
1419 dest->announce_initial = params->announce_initial;
1420 }
1421 if (params->has_announce_max) {
1422 dest->announce_max = params->announce_max;
1423 }
1424 if (params->has_announce_rounds) {
1425 dest->announce_rounds = params->announce_rounds;
1426 }
1427 if (params->has_announce_step) {
1428 dest->announce_step = params->announce_step;
1429 }
1430
1431 if (params->has_block_bitmap_mapping) {
1432 dest->has_block_bitmap_mapping = true;
1433 dest->block_bitmap_mapping = params->block_bitmap_mapping;
1434 }
1435 }
1436
1437 static void migrate_params_apply(MigrateSetParameters *params, Error **errp)
1438 {
1439 MigrationState *s = migrate_get_current();
1440
1441 /* TODO use QAPI_CLONE() instead of duplicating it inline */
1442
1443 if (params->has_compress_level) {
1444 s->parameters.compress_level = params->compress_level;
1445 }
1446
1447 if (params->has_compress_threads) {
1448 s->parameters.compress_threads = params->compress_threads;
1449 }
1450
1451 if (params->has_compress_wait_thread) {
1452 s->parameters.compress_wait_thread = params->compress_wait_thread;
1453 }
1454
1455 if (params->has_decompress_threads) {
1456 s->parameters.decompress_threads = params->decompress_threads;
1457 }
1458
1459 if (params->has_throttle_trigger_threshold) {
1460 s->parameters.throttle_trigger_threshold = params->throttle_trigger_threshold;
1461 }
1462
1463 if (params->has_cpu_throttle_initial) {
1464 s->parameters.cpu_throttle_initial = params->cpu_throttle_initial;
1465 }
1466
1467 if (params->has_cpu_throttle_increment) {
1468 s->parameters.cpu_throttle_increment = params->cpu_throttle_increment;
1469 }
1470
1471 if (params->has_cpu_throttle_tailslow) {
1472 s->parameters.cpu_throttle_tailslow = params->cpu_throttle_tailslow;
1473 }
1474
1475 if (params->has_tls_creds) {
1476 g_free(s->parameters.tls_creds);
1477 assert(params->tls_creds->type == QTYPE_QSTRING);
1478 s->parameters.tls_creds = g_strdup(params->tls_creds->u.s);
1479 }
1480
1481 if (params->has_tls_hostname) {
1482 g_free(s->parameters.tls_hostname);
1483 assert(params->tls_hostname->type == QTYPE_QSTRING);
1484 s->parameters.tls_hostname = g_strdup(params->tls_hostname->u.s);
1485 }
1486
1487 if (params->has_tls_authz) {
1488 g_free(s->parameters.tls_authz);
1489 assert(params->tls_authz->type == QTYPE_QSTRING);
1490 s->parameters.tls_authz = g_strdup(params->tls_authz->u.s);
1491 }
1492
1493 if (params->has_max_bandwidth) {
1494 s->parameters.max_bandwidth = params->max_bandwidth;
1495 if (s->to_dst_file && !migration_in_postcopy()) {
1496 qemu_file_set_rate_limit(s->to_dst_file,
1497 s->parameters.max_bandwidth / XFER_LIMIT_RATIO);
1498 }
1499 }
1500
1501 if (params->has_downtime_limit) {
1502 s->parameters.downtime_limit = params->downtime_limit;
1503 }
1504
1505 if (params->has_x_checkpoint_delay) {
1506 s->parameters.x_checkpoint_delay = params->x_checkpoint_delay;
1507 if (migration_in_colo_state()) {
1508 colo_checkpoint_notify(s);
1509 }
1510 }
1511
1512 if (params->has_block_incremental) {
1513 s->parameters.block_incremental = params->block_incremental;
1514 }
1515 if (params->has_multifd_channels) {
1516 s->parameters.multifd_channels = params->multifd_channels;
1517 }
1518 if (params->has_multifd_compression) {
1519 s->parameters.multifd_compression = params->multifd_compression;
1520 }
1521 if (params->has_xbzrle_cache_size) {
1522 s->parameters.xbzrle_cache_size = params->xbzrle_cache_size;
1523 xbzrle_cache_resize(params->xbzrle_cache_size, errp);
1524 }
1525 if (params->has_max_postcopy_bandwidth) {
1526 s->parameters.max_postcopy_bandwidth = params->max_postcopy_bandwidth;
1527 if (s->to_dst_file && migration_in_postcopy()) {
1528 qemu_file_set_rate_limit(s->to_dst_file,
1529 s->parameters.max_postcopy_bandwidth / XFER_LIMIT_RATIO);
1530 }
1531 }
1532 if (params->has_max_cpu_throttle) {
1533 s->parameters.max_cpu_throttle = params->max_cpu_throttle;
1534 }
1535 if (params->has_announce_initial) {
1536 s->parameters.announce_initial = params->announce_initial;
1537 }
1538 if (params->has_announce_max) {
1539 s->parameters.announce_max = params->announce_max;
1540 }
1541 if (params->has_announce_rounds) {
1542 s->parameters.announce_rounds = params->announce_rounds;
1543 }
1544 if (params->has_announce_step) {
1545 s->parameters.announce_step = params->announce_step;
1546 }
1547
1548 if (params->has_block_bitmap_mapping) {
1549 qapi_free_BitmapMigrationNodeAliasList(
1550 s->parameters.block_bitmap_mapping);
1551
1552 s->parameters.has_block_bitmap_mapping = true;
1553 s->parameters.block_bitmap_mapping =
1554 QAPI_CLONE(BitmapMigrationNodeAliasList,
1555 params->block_bitmap_mapping);
1556 }
1557 }
1558
1559 void qmp_migrate_set_parameters(MigrateSetParameters *params, Error **errp)
1560 {
1561 MigrationParameters tmp;
1562
1563 /* TODO Rewrite "" to null instead */
1564 if (params->has_tls_creds
1565 && params->tls_creds->type == QTYPE_QNULL) {
1566 qobject_unref(params->tls_creds->u.n);
1567 params->tls_creds->type = QTYPE_QSTRING;
1568 params->tls_creds->u.s = strdup("");
1569 }
1570 /* TODO Rewrite "" to null instead */
1571 if (params->has_tls_hostname
1572 && params->tls_hostname->type == QTYPE_QNULL) {
1573 qobject_unref(params->tls_hostname->u.n);
1574 params->tls_hostname->type = QTYPE_QSTRING;
1575 params->tls_hostname->u.s = strdup("");
1576 }
1577
1578 migrate_params_test_apply(params, &tmp);
1579
1580 if (!migrate_params_check(&tmp, errp)) {
1581 /* Invalid parameter */
1582 return;
1583 }
1584
1585 migrate_params_apply(params, errp);
1586 }
1587
1588
1589 void qmp_migrate_start_postcopy(Error **errp)
1590 {
1591 MigrationState *s = migrate_get_current();
1592
1593 if (!migrate_postcopy()) {
1594 error_setg(errp, "Enable postcopy with migrate_set_capability before"
1595 " the start of migration");
1596 return;
1597 }
1598
1599 if (s->state == MIGRATION_STATUS_NONE) {
1600 error_setg(errp, "Postcopy must be started after migration has been"
1601 " started");
1602 return;
1603 }
1604 /*
1605 * we don't error if migration has finished since that would be racy
1606 * with issuing this command.
1607 */
1608 qatomic_set(&s->start_postcopy, true);
1609 }
1610
1611 /* shared migration helpers */
1612
1613 void migrate_set_state(int *state, int old_state, int new_state)
1614 {
1615 assert(new_state < MIGRATION_STATUS__MAX);
1616 if (qatomic_cmpxchg(state, old_state, new_state) == old_state) {
1617 trace_migrate_set_state(MigrationStatus_str(new_state));
1618 migrate_generate_event(new_state);
1619 }
1620 }
1621
1622 static MigrationCapabilityStatusList *migrate_cap_add(
1623 MigrationCapabilityStatusList *list,
1624 MigrationCapability index,
1625 bool state)
1626 {
1627 MigrationCapabilityStatusList *cap;
1628
1629 cap = g_new0(MigrationCapabilityStatusList, 1);
1630 cap->value = g_new0(MigrationCapabilityStatus, 1);
1631 cap->value->capability = index;
1632 cap->value->state = state;
1633 cap->next = list;
1634
1635 return cap;
1636 }
1637
1638 void migrate_set_block_enabled(bool value, Error **errp)
1639 {
1640 MigrationCapabilityStatusList *cap;
1641
1642 cap = migrate_cap_add(NULL, MIGRATION_CAPABILITY_BLOCK, value);
1643 qmp_migrate_set_capabilities(cap, errp);
1644 qapi_free_MigrationCapabilityStatusList(cap);
1645 }
1646
1647 static void migrate_set_block_incremental(MigrationState *s, bool value)
1648 {
1649 s->parameters.block_incremental = value;
1650 }
1651
1652 static void block_cleanup_parameters(MigrationState *s)
1653 {
1654 if (s->must_remove_block_options) {
1655 /* setting to false can never fail */
1656 migrate_set_block_enabled(false, &error_abort);
1657 migrate_set_block_incremental(s, false);
1658 s->must_remove_block_options = false;
1659 }
1660 }
1661
1662 static void migrate_fd_cleanup(MigrationState *s)
1663 {
1664 qemu_bh_delete(s->cleanup_bh);
1665 s->cleanup_bh = NULL;
1666
1667 qemu_savevm_state_cleanup();
1668
1669 if (s->to_dst_file) {
1670 QEMUFile *tmp;
1671
1672 trace_migrate_fd_cleanup();
1673 qemu_mutex_unlock_iothread();
1674 if (s->migration_thread_running) {
1675 qemu_thread_join(&s->thread);
1676 s->migration_thread_running = false;
1677 }
1678 qemu_mutex_lock_iothread();
1679
1680 multifd_save_cleanup();
1681 qemu_mutex_lock(&s->qemu_file_lock);
1682 tmp = s->to_dst_file;
1683 s->to_dst_file = NULL;
1684 qemu_mutex_unlock(&s->qemu_file_lock);
1685 /*
1686 * Close the file handle without the lock to make sure the
1687 * critical section won't block for long.
1688 */
1689 qemu_fclose(tmp);
1690 }
1691
1692 assert(!migration_is_active(s));
1693
1694 if (s->state == MIGRATION_STATUS_CANCELLING) {
1695 migrate_set_state(&s->state, MIGRATION_STATUS_CANCELLING,
1696 MIGRATION_STATUS_CANCELLED);
1697 }
1698
1699 if (s->error) {
1700 /* It is used on info migrate. We can't free it */
1701 error_report_err(error_copy(s->error));
1702 }
1703 notifier_list_notify(&migration_state_notifiers, s);
1704 block_cleanup_parameters(s);
1705 }
1706
1707 static void migrate_fd_cleanup_schedule(MigrationState *s)
1708 {
1709 /*
1710 * Ref the state for bh, because it may be called when
1711 * there're already no other refs
1712 */
1713 object_ref(OBJECT(s));
1714 qemu_bh_schedule(s->cleanup_bh);
1715 }
1716
1717 static void migrate_fd_cleanup_bh(void *opaque)
1718 {
1719 MigrationState *s = opaque;
1720 migrate_fd_cleanup(s);
1721 object_unref(OBJECT(s));
1722 }
1723
1724 void migrate_set_error(MigrationState *s, const Error *error)
1725 {
1726 QEMU_LOCK_GUARD(&s->error_mutex);
1727 if (!s->error) {
1728 s->error = error_copy(error);
1729 }
1730 }
1731
1732 void migrate_fd_error(MigrationState *s, const Error *error)
1733 {
1734 trace_migrate_fd_error(error_get_pretty(error));
1735 assert(s->to_dst_file == NULL);
1736 migrate_set_state(&s->state, MIGRATION_STATUS_SETUP,
1737 MIGRATION_STATUS_FAILED);
1738 migrate_set_error(s, error);
1739 }
1740
1741 static void migrate_fd_cancel(MigrationState *s)
1742 {
1743 int old_state ;
1744 QEMUFile *f = migrate_get_current()->to_dst_file;
1745 trace_migrate_fd_cancel();
1746
1747 if (s->rp_state.from_dst_file) {
1748 /* shutdown the rp socket, so causing the rp thread to shutdown */
1749 qemu_file_shutdown(s->rp_state.from_dst_file);
1750 }
1751
1752 do {
1753 old_state = s->state;
1754 if (!migration_is_running(old_state)) {
1755 break;
1756 }
1757 /* If the migration is paused, kick it out of the pause */
1758 if (old_state == MIGRATION_STATUS_PRE_SWITCHOVER) {
1759 qemu_sem_post(&s->pause_sem);
1760 }
1761 migrate_set_state(&s->state, old_state, MIGRATION_STATUS_CANCELLING);
1762 } while (s->state != MIGRATION_STATUS_CANCELLING);
1763
1764 /*
1765 * If we're unlucky the migration code might be stuck somewhere in a
1766 * send/write while the network has failed and is waiting to timeout;
1767 * if we've got shutdown(2) available then we can force it to quit.
1768 * The outgoing qemu file gets closed in migrate_fd_cleanup that is
1769 * called in a bh, so there is no race against this cancel.
1770 */
1771 if (s->state == MIGRATION_STATUS_CANCELLING && f) {
1772 qemu_file_shutdown(f);
1773 }
1774 if (s->state == MIGRATION_STATUS_CANCELLING && s->block_inactive) {
1775 Error *local_err = NULL;
1776
1777 bdrv_invalidate_cache_all(&local_err);
1778 if (local_err) {
1779 error_report_err(local_err);
1780 } else {
1781 s->block_inactive = false;
1782 }
1783 }
1784 }
1785
1786 void add_migration_state_change_notifier(Notifier *notify)
1787 {
1788 notifier_list_add(&migration_state_notifiers, notify);
1789 }
1790
1791 void remove_migration_state_change_notifier(Notifier *notify)
1792 {
1793 notifier_remove(notify);
1794 }
1795
1796 bool migration_in_setup(MigrationState *s)
1797 {
1798 return s->state == MIGRATION_STATUS_SETUP;
1799 }
1800
1801 bool migration_has_finished(MigrationState *s)
1802 {
1803 return s->state == MIGRATION_STATUS_COMPLETED;
1804 }
1805
1806 bool migration_has_failed(MigrationState *s)
1807 {
1808 return (s->state == MIGRATION_STATUS_CANCELLED ||
1809 s->state == MIGRATION_STATUS_FAILED);
1810 }
1811
1812 bool migration_in_postcopy(void)
1813 {
1814 MigrationState *s = migrate_get_current();
1815
1816 switch (s->state) {
1817 case MIGRATION_STATUS_POSTCOPY_ACTIVE:
1818 case MIGRATION_STATUS_POSTCOPY_PAUSED:
1819 case MIGRATION_STATUS_POSTCOPY_RECOVER:
1820 return true;
1821 default:
1822 return false;
1823 }
1824 }
1825
1826 bool migration_in_postcopy_after_devices(MigrationState *s)
1827 {
1828 return migration_in_postcopy() && s->postcopy_after_devices;
1829 }
1830
1831 bool migration_in_incoming_postcopy(void)
1832 {
1833 PostcopyState ps = postcopy_state_get();
1834
1835 return ps >= POSTCOPY_INCOMING_DISCARD && ps < POSTCOPY_INCOMING_END;
1836 }
1837
1838 bool migration_is_idle(void)
1839 {
1840 MigrationState *s = current_migration;
1841
1842 if (!s) {
1843 return true;
1844 }
1845
1846 switch (s->state) {
1847 case MIGRATION_STATUS_NONE:
1848 case MIGRATION_STATUS_CANCELLED:
1849 case MIGRATION_STATUS_COMPLETED:
1850 case MIGRATION_STATUS_FAILED:
1851 return true;
1852 case MIGRATION_STATUS_SETUP:
1853 case MIGRATION_STATUS_CANCELLING:
1854 case MIGRATION_STATUS_ACTIVE:
1855 case MIGRATION_STATUS_POSTCOPY_ACTIVE:
1856 case MIGRATION_STATUS_COLO:
1857 case MIGRATION_STATUS_PRE_SWITCHOVER:
1858 case MIGRATION_STATUS_DEVICE:
1859 case MIGRATION_STATUS_WAIT_UNPLUG:
1860 return false;
1861 case MIGRATION_STATUS__MAX:
1862 g_assert_not_reached();
1863 }
1864
1865 return false;
1866 }
1867
1868 bool migration_is_active(MigrationState *s)
1869 {
1870 return (s->state == MIGRATION_STATUS_ACTIVE ||
1871 s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE);
1872 }
1873
1874 void migrate_init(MigrationState *s)
1875 {
1876 /*
1877 * Reinitialise all migration state, except
1878 * parameters/capabilities that the user set, and
1879 * locks.
1880 */
1881 s->cleanup_bh = 0;
1882 s->to_dst_file = NULL;
1883 s->state = MIGRATION_STATUS_NONE;
1884 s->rp_state.from_dst_file = NULL;
1885 s->rp_state.error = false;
1886 s->mbps = 0.0;
1887 s->pages_per_second = 0.0;
1888 s->downtime = 0;
1889 s->expected_downtime = 0;
1890 s->setup_time = 0;
1891 s->start_postcopy = false;
1892 s->postcopy_after_devices = false;
1893 s->migration_thread_running = false;
1894 error_free(s->error);
1895 s->error = NULL;
1896 s->hostname = NULL;
1897
1898 migrate_set_state(&s->state, MIGRATION_STATUS_NONE, MIGRATION_STATUS_SETUP);
1899
1900 s->start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
1901 s->total_time = 0;
1902 s->vm_was_running = false;
1903 s->iteration_initial_bytes = 0;
1904 s->threshold_size = 0;
1905 }
1906
1907 static GSList *migration_blockers;
1908
1909 int migrate_add_blocker(Error *reason, Error **errp)
1910 {
1911 if (only_migratable) {
1912 error_propagate_prepend(errp, error_copy(reason),
1913 "disallowing migration blocker "
1914 "(--only-migratable) for: ");
1915 return -EACCES;
1916 }
1917
1918 if (migration_is_idle()) {
1919 migration_blockers = g_slist_prepend(migration_blockers, reason);
1920 return 0;
1921 }
1922
1923 error_propagate_prepend(errp, error_copy(reason),
1924 "disallowing migration blocker "
1925 "(migration in progress) for: ");
1926 return -EBUSY;
1927 }
1928
1929 void migrate_del_blocker(Error *reason)
1930 {
1931 migration_blockers = g_slist_remove(migration_blockers, reason);
1932 }
1933
1934 void qmp_migrate_incoming(const char *uri, Error **errp)
1935 {
1936 Error *local_err = NULL;
1937 static bool once = true;
1938
1939 if (!deferred_incoming) {
1940 error_setg(errp, "For use with '-incoming defer'");
1941 return;
1942 }
1943 if (!once) {
1944 error_setg(errp, "The incoming migration has already been started");
1945 return;
1946 }
1947
1948 qemu_start_incoming_migration(uri, &local_err);
1949
1950 if (local_err) {
1951 error_propagate(errp, local_err);
1952 return;
1953 }
1954
1955 once = false;
1956 }
1957
1958 void qmp_migrate_recover(const char *uri, Error **errp)
1959 {
1960 MigrationIncomingState *mis = migration_incoming_get_current();
1961
1962 if (mis->state != MIGRATION_STATUS_POSTCOPY_PAUSED) {
1963 error_setg(errp, "Migrate recover can only be run "
1964 "when postcopy is paused.");
1965 return;
1966 }
1967
1968 if (qatomic_cmpxchg(&mis->postcopy_recover_triggered,
1969 false, true) == true) {
1970 error_setg(errp, "Migrate recovery is triggered already");
1971 return;
1972 }
1973
1974 /*
1975 * Note that this call will never start a real migration; it will
1976 * only re-setup the migration stream and poke existing migration
1977 * to continue using that newly established channel.
1978 */
1979 qemu_start_incoming_migration(uri, errp);
1980 }
1981
1982 void qmp_migrate_pause(Error **errp)
1983 {
1984 MigrationState *ms = migrate_get_current();
1985 MigrationIncomingState *mis = migration_incoming_get_current();
1986 int ret;
1987
1988 if (ms->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) {
1989 /* Source side, during postcopy */
1990 qemu_mutex_lock(&ms->qemu_file_lock);
1991 ret = qemu_file_shutdown(ms->to_dst_file);
1992 qemu_mutex_unlock(&ms->qemu_file_lock);
1993 if (ret) {
1994 error_setg(errp, "Failed to pause source migration");
1995 }
1996 return;
1997 }
1998
1999 if (mis->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) {
2000 ret = qemu_file_shutdown(mis->from_src_file);
2001 if (ret) {
2002 error_setg(errp, "Failed to pause destination migration");
2003 }
2004 return;
2005 }
2006
2007 error_setg(errp, "migrate-pause is currently only supported "
2008 "during postcopy-active state");
2009 }
2010
2011 bool migration_is_blocked(Error **errp)
2012 {
2013 if (qemu_savevm_state_blocked(errp)) {
2014 return true;
2015 }
2016
2017 if (migration_blockers) {
2018 error_propagate(errp, error_copy(migration_blockers->data));
2019 return true;
2020 }
2021
2022 return false;
2023 }
2024
2025 /* Returns true if continue to migrate, or false if error detected */
2026 static bool migrate_prepare(MigrationState *s, bool blk, bool blk_inc,
2027 bool resume, Error **errp)
2028 {
2029 Error *local_err = NULL;
2030
2031 if (resume) {
2032 if (s->state != MIGRATION_STATUS_POSTCOPY_PAUSED) {
2033 error_setg(errp, "Cannot resume if there is no "
2034 "paused migration");
2035 return false;
2036 }
2037
2038 /*
2039 * Postcopy recovery won't work well with release-ram
2040 * capability since release-ram will drop the page buffer as
2041 * long as the page is put into the send buffer. So if there
2042 * is a network failure happened, any page buffers that have
2043 * not yet reached the destination VM but have already been
2044 * sent from the source VM will be lost forever. Let's refuse
2045 * the client from resuming such a postcopy migration.
2046 * Luckily release-ram was designed to only be used when src
2047 * and destination VMs are on the same host, so it should be
2048 * fine.
2049 */
2050 if (migrate_release_ram()) {
2051 error_setg(errp, "Postcopy recovery cannot work "
2052 "when release-ram capability is set");
2053 return false;
2054 }
2055
2056 /* This is a resume, skip init status */
2057 return true;
2058 }
2059
2060 if (migration_is_running(s->state)) {
2061 error_setg(errp, QERR_MIGRATION_ACTIVE);
2062 return false;
2063 }
2064
2065 if (runstate_check(RUN_STATE_INMIGRATE)) {
2066 error_setg(errp, "Guest is waiting for an incoming migration");
2067 return false;
2068 }
2069
2070 if (migration_is_blocked(errp)) {
2071 return false;
2072 }
2073
2074 if (blk || blk_inc) {
2075 if (migrate_use_block() || migrate_use_block_incremental()) {
2076 error_setg(errp, "Command options are incompatible with "
2077 "current migration capabilities");
2078 return false;
2079 }
2080 migrate_set_block_enabled(true, &local_err);
2081 if (local_err) {
2082 error_propagate(errp, local_err);
2083 return false;
2084 }
2085 s->must_remove_block_options = true;
2086 }
2087
2088 if (blk_inc) {
2089 migrate_set_block_incremental(s, true);
2090 }
2091
2092 migrate_init(s);
2093 /*
2094 * set ram_counters memory to zero for a
2095 * new migration
2096 */
2097 memset(&ram_counters, 0, sizeof(ram_counters));
2098
2099 return true;
2100 }
2101
2102 void qmp_migrate(const char *uri, bool has_blk, bool blk,
2103 bool has_inc, bool inc, bool has_detach, bool detach,
2104 bool has_resume, bool resume, Error **errp)
2105 {
2106 Error *local_err = NULL;
2107 MigrationState *s = migrate_get_current();
2108 const char *p = NULL;
2109
2110 if (!migrate_prepare(s, has_blk && blk, has_inc && inc,
2111 has_resume && resume, errp)) {
2112 /* Error detected, put into errp */
2113 return;
2114 }
2115
2116 if (strstart(uri, "tcp:", &p) ||
2117 strstart(uri, "unix:", NULL) ||
2118 strstart(uri, "vsock:", NULL)) {
2119 socket_start_outgoing_migration(s, p ? p : uri, &local_err);
2120 #ifdef CONFIG_RDMA
2121 } else if (strstart(uri, "rdma:", &p)) {
2122 rdma_start_outgoing_migration(s, p, &local_err);
2123 #endif
2124 } else if (strstart(uri, "exec:", &p)) {
2125 exec_start_outgoing_migration(s, p, &local_err);
2126 } else if (strstart(uri, "fd:", &p)) {
2127 fd_start_outgoing_migration(s, p, &local_err);
2128 } else {
2129 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "uri",
2130 "a valid migration protocol");
2131 migrate_set_state(&s->state, MIGRATION_STATUS_SETUP,
2132 MIGRATION_STATUS_FAILED);
2133 block_cleanup_parameters(s);
2134 return;
2135 }
2136
2137 if (local_err) {
2138 migrate_fd_error(s, local_err);
2139 error_propagate(errp, local_err);
2140 return;
2141 }
2142 }
2143
2144 void qmp_migrate_cancel(Error **errp)
2145 {
2146 migrate_fd_cancel(migrate_get_current());
2147 }
2148
2149 void qmp_migrate_continue(MigrationStatus state, Error **errp)
2150 {
2151 MigrationState *s = migrate_get_current();
2152 if (s->state != state) {
2153 error_setg(errp, "Migration not in expected state: %s",
2154 MigrationStatus_str(s->state));
2155 return;
2156 }
2157 qemu_sem_post(&s->pause_sem);
2158 }
2159
2160 void qmp_migrate_set_cache_size(int64_t value, Error **errp)
2161 {
2162 MigrateSetParameters p = {
2163 .has_xbzrle_cache_size = true,
2164 .xbzrle_cache_size = value,
2165 };
2166
2167 qmp_migrate_set_parameters(&p, errp);
2168 }
2169
2170 int64_t qmp_query_migrate_cache_size(Error **errp)
2171 {
2172 return migrate_xbzrle_cache_size();
2173 }
2174
2175 void qmp_migrate_set_speed(int64_t value, Error **errp)
2176 {
2177 MigrateSetParameters p = {
2178 .has_max_bandwidth = true,
2179 .max_bandwidth = value,
2180 };
2181
2182 qmp_migrate_set_parameters(&p, errp);
2183 }
2184
2185 void qmp_migrate_set_downtime(double value, Error **errp)
2186 {
2187 if (value < 0 || value > MAX_MIGRATE_DOWNTIME_SECONDS) {
2188 error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
2189 "downtime_limit",
2190 "an integer in the range of 0 to "
2191 stringify(MAX_MIGRATE_DOWNTIME_SECONDS)" seconds");
2192 return;
2193 }
2194
2195 value *= 1000; /* Convert to milliseconds */
2196
2197 MigrateSetParameters p = {
2198 .has_downtime_limit = true,
2199 .downtime_limit = (int64_t)value,
2200 };
2201
2202 qmp_migrate_set_parameters(&p, errp);
2203 }
2204
2205 bool migrate_release_ram(void)
2206 {
2207 MigrationState *s;
2208
2209 s = migrate_get_current();
2210
2211 return s->enabled_capabilities[MIGRATION_CAPABILITY_RELEASE_RAM];
2212 }
2213
2214 bool migrate_postcopy_ram(void)
2215 {
2216 MigrationState *s;
2217
2218 s = migrate_get_current();
2219
2220 return s->enabled_capabilities[MIGRATION_CAPABILITY_POSTCOPY_RAM];
2221 }
2222
2223 bool migrate_postcopy(void)
2224 {
2225 return migrate_postcopy_ram() || migrate_dirty_bitmaps();
2226 }
2227
2228 bool migrate_auto_converge(void)
2229 {
2230 MigrationState *s;
2231
2232 s = migrate_get_current();
2233
2234 return s->enabled_capabilities[MIGRATION_CAPABILITY_AUTO_CONVERGE];
2235 }
2236
2237 bool migrate_zero_blocks(void)
2238 {
2239 MigrationState *s;
2240
2241 s = migrate_get_current();
2242
2243 return s->enabled_capabilities[MIGRATION_CAPABILITY_ZERO_BLOCKS];
2244 }
2245
2246 bool migrate_postcopy_blocktime(void)
2247 {
2248 MigrationState *s;
2249
2250 s = migrate_get_current();
2251
2252 return s->enabled_capabilities[MIGRATION_CAPABILITY_POSTCOPY_BLOCKTIME];
2253 }
2254
2255 bool migrate_use_compression(void)
2256 {
2257 MigrationState *s;
2258
2259 s = migrate_get_current();
2260
2261 return s->enabled_capabilities[MIGRATION_CAPABILITY_COMPRESS];
2262 }
2263
2264 int migrate_compress_level(void)
2265 {
2266 MigrationState *s;
2267
2268 s = migrate_get_current();
2269
2270 return s->parameters.compress_level;
2271 }
2272
2273 int migrate_compress_threads(void)
2274 {
2275 MigrationState *s;
2276
2277 s = migrate_get_current();
2278
2279 return s->parameters.compress_threads;
2280 }
2281
2282 int migrate_compress_wait_thread(void)
2283 {
2284 MigrationState *s;
2285
2286 s = migrate_get_current();
2287
2288 return s->parameters.compress_wait_thread;
2289 }
2290
2291 int migrate_decompress_threads(void)
2292 {
2293 MigrationState *s;
2294
2295 s = migrate_get_current();
2296
2297 return s->parameters.decompress_threads;
2298 }
2299
2300 bool migrate_dirty_bitmaps(void)
2301 {
2302 MigrationState *s;
2303
2304 s = migrate_get_current();
2305
2306 return s->enabled_capabilities[MIGRATION_CAPABILITY_DIRTY_BITMAPS];
2307 }
2308
2309 bool migrate_ignore_shared(void)
2310 {
2311 MigrationState *s;
2312
2313 s = migrate_get_current();
2314
2315 return s->enabled_capabilities[MIGRATION_CAPABILITY_X_IGNORE_SHARED];
2316 }
2317
2318 bool migrate_validate_uuid(void)
2319 {
2320 MigrationState *s;
2321
2322 s = migrate_get_current();
2323
2324 return s->enabled_capabilities[MIGRATION_CAPABILITY_VALIDATE_UUID];
2325 }
2326
2327 bool migrate_use_events(void)
2328 {
2329 MigrationState *s;
2330
2331 s = migrate_get_current();
2332
2333 return s->enabled_capabilities[MIGRATION_CAPABILITY_EVENTS];
2334 }
2335
2336 bool migrate_use_multifd(void)
2337 {
2338 MigrationState *s;
2339
2340 s = migrate_get_current();
2341
2342 return s->enabled_capabilities[MIGRATION_CAPABILITY_MULTIFD];
2343 }
2344
2345 bool migrate_pause_before_switchover(void)
2346 {
2347 MigrationState *s;
2348
2349 s = migrate_get_current();
2350
2351 return s->enabled_capabilities[
2352 MIGRATION_CAPABILITY_PAUSE_BEFORE_SWITCHOVER];
2353 }
2354
2355 int migrate_multifd_channels(void)
2356 {
2357 MigrationState *s;
2358
2359 s = migrate_get_current();
2360
2361 return s->parameters.multifd_channels;
2362 }
2363
2364 MultiFDCompression migrate_multifd_compression(void)
2365 {
2366 MigrationState *s;
2367
2368 s = migrate_get_current();
2369
2370 return s->parameters.multifd_compression;
2371 }
2372
2373 int migrate_multifd_zlib_level(void)
2374 {
2375 MigrationState *s;
2376
2377 s = migrate_get_current();
2378
2379 return s->parameters.multifd_zlib_level;
2380 }
2381
2382 int migrate_multifd_zstd_level(void)
2383 {
2384 MigrationState *s;
2385
2386 s = migrate_get_current();
2387
2388 return s->parameters.multifd_zstd_level;
2389 }
2390
2391 int migrate_use_xbzrle(void)
2392 {
2393 MigrationState *s;
2394
2395 s = migrate_get_current();
2396
2397 return s->enabled_capabilities[MIGRATION_CAPABILITY_XBZRLE];
2398 }
2399
2400 int64_t migrate_xbzrle_cache_size(void)
2401 {
2402 MigrationState *s;
2403
2404 s = migrate_get_current();
2405
2406 return s->parameters.xbzrle_cache_size;
2407 }
2408
2409 static int64_t migrate_max_postcopy_bandwidth(void)
2410 {
2411 MigrationState *s;
2412
2413 s = migrate_get_current();
2414
2415 return s->parameters.max_postcopy_bandwidth;
2416 }
2417
2418 bool migrate_use_block(void)
2419 {
2420 MigrationState *s;
2421
2422 s = migrate_get_current();
2423
2424 return s->enabled_capabilities[MIGRATION_CAPABILITY_BLOCK];
2425 }
2426
2427 bool migrate_use_return_path(void)
2428 {
2429 MigrationState *s;
2430
2431 s = migrate_get_current();
2432
2433 return s->enabled_capabilities[MIGRATION_CAPABILITY_RETURN_PATH];
2434 }
2435
2436 bool migrate_use_block_incremental(void)
2437 {
2438 MigrationState *s;
2439
2440 s = migrate_get_current();
2441
2442 return s->parameters.block_incremental;
2443 }
2444
2445 /* migration thread support */
2446 /*
2447 * Something bad happened to the RP stream, mark an error
2448 * The caller shall print or trace something to indicate why
2449 */
2450 static void mark_source_rp_bad(MigrationState *s)
2451 {
2452 s->rp_state.error = true;
2453 }
2454
2455 static struct rp_cmd_args {
2456 ssize_t len; /* -1 = variable */
2457 const char *name;
2458 } rp_cmd_args[] = {
2459 [MIG_RP_MSG_INVALID] = { .len = -1, .name = "INVALID" },
2460 [MIG_RP_MSG_SHUT] = { .len = 4, .name = "SHUT" },
2461 [MIG_RP_MSG_PONG] = { .len = 4, .name = "PONG" },
2462 [MIG_RP_MSG_REQ_PAGES] = { .len = 12, .name = "REQ_PAGES" },
2463 [MIG_RP_MSG_REQ_PAGES_ID] = { .len = -1, .name = "REQ_PAGES_ID" },
2464 [MIG_RP_MSG_RECV_BITMAP] = { .len = -1, .name = "RECV_BITMAP" },
2465 [MIG_RP_MSG_RESUME_ACK] = { .len = 4, .name = "RESUME_ACK" },
2466 [MIG_RP_MSG_MAX] = { .len = -1, .name = "MAX" },
2467 };
2468
2469 /*
2470 * Process a request for pages received on the return path,
2471 * We're allowed to send more than requested (e.g. to round to our page size)
2472 * and we don't need to send pages that have already been sent.
2473 */
2474 static void migrate_handle_rp_req_pages(MigrationState *ms, const char* rbname,
2475 ram_addr_t start, size_t len)
2476 {
2477 long our_host_ps = qemu_real_host_page_size;
2478
2479 trace_migrate_handle_rp_req_pages(rbname, start, len);
2480
2481 /*
2482 * Since we currently insist on matching page sizes, just sanity check
2483 * we're being asked for whole host pages.
2484 */
2485 if (start & (our_host_ps-1) ||
2486 (len & (our_host_ps-1))) {
2487 error_report("%s: Misaligned page request, start: " RAM_ADDR_FMT
2488 " len: %zd", __func__, start, len);
2489 mark_source_rp_bad(ms);
2490 return;
2491 }
2492
2493 if (ram_save_queue_pages(rbname, start, len)) {
2494 mark_source_rp_bad(ms);
2495 }
2496 }
2497
2498 /* Return true to retry, false to quit */
2499 static bool postcopy_pause_return_path_thread(MigrationState *s)
2500 {
2501 trace_postcopy_pause_return_path();
2502
2503 qemu_sem_wait(&s->postcopy_pause_rp_sem);
2504
2505 trace_postcopy_pause_return_path_continued();
2506
2507 return true;
2508 }
2509
2510 static int migrate_handle_rp_recv_bitmap(MigrationState *s, char *block_name)
2511 {
2512 RAMBlock *block = qemu_ram_block_by_name(block_name);
2513
2514 if (!block) {
2515 error_report("%s: invalid block name '%s'", __func__, block_name);
2516 return -EINVAL;
2517 }
2518
2519 /* Fetch the received bitmap and refresh the dirty bitmap */
2520 return ram_dirty_bitmap_reload(s, block);
2521 }
2522
2523 static int migrate_handle_rp_resume_ack(MigrationState *s, uint32_t value)
2524 {
2525 trace_source_return_path_thread_resume_ack(value);
2526
2527 if (value != MIGRATION_RESUME_ACK_VALUE) {
2528 error_report("%s: illegal resume_ack value %"PRIu32,
2529 __func__, value);
2530 return -1;
2531 }
2532
2533 /* Now both sides are active. */
2534 migrate_set_state(&s->state, MIGRATION_STATUS_POSTCOPY_RECOVER,
2535 MIGRATION_STATUS_POSTCOPY_ACTIVE);
2536
2537 /* Notify send thread that time to continue send pages */
2538 qemu_sem_post(&s->rp_state.rp_sem);
2539
2540 return 0;
2541 }
2542
2543 /*
2544 * Handles messages sent on the return path towards the source VM
2545 *
2546 */
2547 static void *source_return_path_thread(void *opaque)
2548 {
2549 MigrationState *ms = opaque;
2550 QEMUFile *rp = ms->rp_state.from_dst_file;
2551 uint16_t header_len, header_type;
2552 uint8_t buf[512];
2553 uint32_t tmp32, sibling_error;
2554 ram_addr_t start = 0; /* =0 to silence warning */
2555 size_t len = 0, expected_len;
2556 int res;
2557
2558 trace_source_return_path_thread_entry();
2559 rcu_register_thread();
2560
2561 retry:
2562 while (!ms->rp_state.error && !qemu_file_get_error(rp) &&
2563 migration_is_setup_or_active(ms->state)) {
2564 trace_source_return_path_thread_loop_top();
2565 header_type = qemu_get_be16(rp);
2566 header_len = qemu_get_be16(rp);
2567
2568 if (qemu_file_get_error(rp)) {
2569 mark_source_rp_bad(ms);
2570 goto out;
2571 }
2572
2573 if (header_type >= MIG_RP_MSG_MAX ||
2574 header_type == MIG_RP_MSG_INVALID) {
2575 error_report("RP: Received invalid message 0x%04x length 0x%04x",
2576 header_type, header_len);
2577 mark_source_rp_bad(ms);
2578 goto out;
2579 }
2580
2581 if ((rp_cmd_args[header_type].len != -1 &&
2582 header_len != rp_cmd_args[header_type].len) ||
2583 header_len > sizeof(buf)) {
2584 error_report("RP: Received '%s' message (0x%04x) with"
2585 "incorrect length %d expecting %zu",
2586 rp_cmd_args[header_type].name, header_type, header_len,
2587 (size_t)rp_cmd_args[header_type].len);
2588 mark_source_rp_bad(ms);
2589 goto out;
2590 }
2591
2592 /* We know we've got a valid header by this point */
2593 res = qemu_get_buffer(rp, buf, header_len);
2594 if (res != header_len) {
2595 error_report("RP: Failed reading data for message 0x%04x"
2596 " read %d expected %d",
2597 header_type, res, header_len);
2598 mark_source_rp_bad(ms);
2599 goto out;
2600 }
2601
2602 /* OK, we have the message and the data */
2603 switch (header_type) {
2604 case MIG_RP_MSG_SHUT:
2605 sibling_error = ldl_be_p(buf);
2606 trace_source_return_path_thread_shut(sibling_error);
2607 if (sibling_error) {
2608 error_report("RP: Sibling indicated error %d", sibling_error);
2609 mark_source_rp_bad(ms);
2610 }
2611 /*
2612 * We'll let the main thread deal with closing the RP
2613 * we could do a shutdown(2) on it, but we're the only user
2614 * anyway, so there's nothing gained.
2615 */
2616 goto out;
2617
2618 case MIG_RP_MSG_PONG:
2619 tmp32 = ldl_be_p(buf);
2620 trace_source_return_path_thread_pong(tmp32);
2621 break;
2622
2623 case MIG_RP_MSG_REQ_PAGES:
2624 start = ldq_be_p(buf);
2625 len = ldl_be_p(buf + 8);
2626 migrate_handle_rp_req_pages(ms, NULL, start, len);
2627 break;
2628
2629 case MIG_RP_MSG_REQ_PAGES_ID:
2630 expected_len = 12 + 1; /* header + termination */
2631
2632 if (header_len >= expected_len) {
2633 start = ldq_be_p(buf);
2634 len = ldl_be_p(buf + 8);
2635 /* Now we expect an idstr */
2636 tmp32 = buf[12]; /* Length of the following idstr */
2637 buf[13 + tmp32] = '\0';
2638 expected_len += tmp32;
2639 }
2640 if (header_len != expected_len) {
2641 error_report("RP: Req_Page_id with length %d expecting %zd",
2642 header_len, expected_len);
2643 mark_source_rp_bad(ms);
2644 goto out;
2645 }
2646 migrate_handle_rp_req_pages(ms, (char *)&buf[13], start, len);
2647 break;
2648
2649 case MIG_RP_MSG_RECV_BITMAP:
2650 if (header_len < 1) {
2651 error_report("%s: missing block name", __func__);
2652 mark_source_rp_bad(ms);
2653 goto out;
2654 }
2655 /* Format: len (1B) + idstr (<255B). This ends the idstr. */
2656 buf[buf[0] + 1] = '\0';
2657 if (migrate_handle_rp_recv_bitmap(ms, (char *)(buf + 1))) {
2658 mark_source_rp_bad(ms);
2659 goto out;
2660 }
2661 break;
2662
2663 case MIG_RP_MSG_RESUME_ACK:
2664 tmp32 = ldl_be_p(buf);
2665 if (migrate_handle_rp_resume_ack(ms, tmp32)) {
2666 mark_source_rp_bad(ms);
2667 goto out;
2668 }
2669 break;
2670
2671 default:
2672 break;
2673 }
2674 }
2675
2676 out:
2677 res = qemu_file_get_error(rp);
2678 if (res) {
2679 if (res == -EIO && migration_in_postcopy()) {
2680 /*
2681 * Maybe there is something we can do: it looks like a
2682 * network down issue, and we pause for a recovery.
2683 */
2684 if (postcopy_pause_return_path_thread(ms)) {
2685 /* Reload rp, reset the rest */
2686 if (rp != ms->rp_state.from_dst_file) {
2687 qemu_fclose(rp);
2688 rp = ms->rp_state.from_dst_file;
2689 }
2690 ms->rp_state.error = false;
2691 goto retry;
2692 }
2693 }
2694
2695 trace_source_return_path_thread_bad_end();
2696 mark_source_rp_bad(ms);
2697 }
2698
2699 trace_source_return_path_thread_end();
2700 ms->rp_state.from_dst_file = NULL;
2701 qemu_fclose(rp);
2702 rcu_unregister_thread();
2703 return NULL;
2704 }
2705
2706 static int open_return_path_on_source(MigrationState *ms,
2707 bool create_thread)
2708 {
2709
2710 ms->rp_state.from_dst_file = qemu_file_get_return_path(ms->to_dst_file);
2711 if (!ms->rp_state.from_dst_file) {
2712 return -1;
2713 }
2714
2715 trace_open_return_path_on_source();
2716
2717 if (!create_thread) {
2718 /* We're done */
2719 return 0;
2720 }
2721
2722 qemu_thread_create(&ms->rp_state.rp_thread, "return path",
2723 source_return_path_thread, ms, QEMU_THREAD_JOINABLE);
2724
2725 trace_open_return_path_on_source_continue();
2726
2727 return 0;
2728 }
2729
2730 /* Returns 0 if the RP was ok, otherwise there was an error on the RP */
2731 static int await_return_path_close_on_source(MigrationState *ms)
2732 {
2733 /*
2734 * If this is a normal exit then the destination will send a SHUT and the
2735 * rp_thread will exit, however if there's an error we need to cause
2736 * it to exit.
2737 */
2738 if (qemu_file_get_error(ms->to_dst_file) && ms->rp_state.from_dst_file) {
2739 /*
2740 * shutdown(2), if we have it, will cause it to unblock if it's stuck
2741 * waiting for the destination.
2742 */
2743 qemu_file_shutdown(ms->rp_state.from_dst_file);
2744 mark_source_rp_bad(ms);
2745 }
2746 trace_await_return_path_close_on_source_joining();
2747 qemu_thread_join(&ms->rp_state.rp_thread);
2748 trace_await_return_path_close_on_source_close();
2749 return ms->rp_state.error;
2750 }
2751
2752 /*
2753 * Switch from normal iteration to postcopy
2754 * Returns non-0 on error
2755 */
2756 static int postcopy_start(MigrationState *ms)
2757 {
2758 int ret;
2759 QIOChannelBuffer *bioc;
2760 QEMUFile *fb;
2761 int64_t time_at_stop = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
2762 int64_t bandwidth = migrate_max_postcopy_bandwidth();
2763 bool restart_block = false;
2764 int cur_state = MIGRATION_STATUS_ACTIVE;
2765 if (!migrate_pause_before_switchover()) {
2766 migrate_set_state(&ms->state, MIGRATION_STATUS_ACTIVE,
2767 MIGRATION_STATUS_POSTCOPY_ACTIVE);
2768 }
2769
2770 trace_postcopy_start();
2771 qemu_mutex_lock_iothread();
2772 trace_postcopy_start_set_run();
2773
2774 qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER, NULL);
2775 global_state_store();
2776 ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
2777 if (ret < 0) {
2778 goto fail;
2779 }
2780
2781 ret = migration_maybe_pause(ms, &cur_state,
2782 MIGRATION_STATUS_POSTCOPY_ACTIVE);
2783 if (ret < 0) {
2784 goto fail;
2785 }
2786
2787 ret = bdrv_inactivate_all();
2788 if (ret < 0) {
2789 goto fail;
2790 }
2791 restart_block = true;
2792
2793 /*
2794 * Cause any non-postcopiable, but iterative devices to
2795 * send out their final data.
2796 */
2797 qemu_savevm_state_complete_precopy(ms->to_dst_file, true, false);
2798
2799 /*
2800 * in Finish migrate and with the io-lock held everything should
2801 * be quiet, but we've potentially still got dirty pages and we
2802 * need to tell the destination to throw any pages it's already received
2803 * that are dirty
2804 */
2805 if (migrate_postcopy_ram()) {
2806 if (ram_postcopy_send_discard_bitmap(ms)) {
2807 error_report("postcopy send discard bitmap failed");
2808 goto fail;
2809 }
2810 }
2811
2812 /*
2813 * send rest of state - note things that are doing postcopy
2814 * will notice we're in POSTCOPY_ACTIVE and not actually
2815 * wrap their state up here
2816 */
2817 /* 0 max-postcopy-bandwidth means unlimited */
2818 if (!bandwidth) {
2819 qemu_file_set_rate_limit(ms->to_dst_file, INT64_MAX);
2820 } else {
2821 qemu_file_set_rate_limit(ms->to_dst_file, bandwidth / XFER_LIMIT_RATIO);
2822 }
2823 if (migrate_postcopy_ram()) {
2824 /* Ping just for debugging, helps line traces up */
2825 qemu_savevm_send_ping(ms->to_dst_file, 2);
2826 }
2827
2828 /*
2829 * While loading the device state we may trigger page transfer
2830 * requests and the fd must be free to process those, and thus
2831 * the destination must read the whole device state off the fd before
2832 * it starts processing it. Unfortunately the ad-hoc migration format
2833 * doesn't allow the destination to know the size to read without fully
2834 * parsing it through each devices load-state code (especially the open
2835 * coded devices that use get/put).
2836 * So we wrap the device state up in a package with a length at the start;
2837 * to do this we use a qemu_buf to hold the whole of the device state.
2838 */
2839 bioc = qio_channel_buffer_new(4096);
2840 qio_channel_set_name(QIO_CHANNEL(bioc), "migration-postcopy-buffer");
2841 fb = qemu_fopen_channel_output(QIO_CHANNEL(bioc));
2842 object_unref(OBJECT(bioc));
2843
2844 /*
2845 * Make sure the receiver can get incoming pages before we send the rest
2846 * of the state
2847 */
2848 qemu_savevm_send_postcopy_listen(fb);
2849
2850 qemu_savevm_state_complete_precopy(fb, false, false);
2851 if (migrate_postcopy_ram()) {
2852 qemu_savevm_send_ping(fb, 3);
2853 }
2854
2855 qemu_savevm_send_postcopy_run(fb);
2856
2857 /* <><> end of stuff going into the package */
2858
2859 /* Last point of recovery; as soon as we send the package the destination
2860 * can open devices and potentially start running.
2861 * Lets just check again we've not got any errors.
2862 */
2863 ret = qemu_file_get_error(ms->to_dst_file);
2864 if (ret) {
2865 error_report("postcopy_start: Migration stream errored (pre package)");
2866 goto fail_closefb;
2867 }
2868
2869 restart_block = false;
2870
2871 /* Now send that blob */
2872 if (qemu_savevm_send_packaged(ms->to_dst_file, bioc->data, bioc->usage)) {
2873 goto fail_closefb;
2874 }
2875 qemu_fclose(fb);
2876
2877 /* Send a notify to give a chance for anything that needs to happen
2878 * at the transition to postcopy and after the device state; in particular
2879 * spice needs to trigger a transition now
2880 */
2881 ms->postcopy_after_devices = true;
2882 notifier_list_notify(&migration_state_notifiers, ms);
2883
2884 ms->downtime = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) - time_at_stop;
2885
2886 qemu_mutex_unlock_iothread();
2887
2888 if (migrate_postcopy_ram()) {
2889 /*
2890 * Although this ping is just for debug, it could potentially be
2891 * used for getting a better measurement of downtime at the source.
2892 */
2893 qemu_savevm_send_ping(ms->to_dst_file, 4);
2894 }
2895
2896 if (migrate_release_ram()) {
2897 ram_postcopy_migrated_memory_release(ms);
2898 }
2899
2900 ret = qemu_file_get_error(ms->to_dst_file);
2901 if (ret) {
2902 error_report("postcopy_start: Migration stream errored");
2903 migrate_set_state(&ms->state, MIGRATION_STATUS_POSTCOPY_ACTIVE,
2904 MIGRATION_STATUS_FAILED);
2905 }
2906
2907 return ret;
2908
2909 fail_closefb:
2910 qemu_fclose(fb);
2911 fail:
2912 migrate_set_state(&ms->state, MIGRATION_STATUS_POSTCOPY_ACTIVE,
2913 MIGRATION_STATUS_FAILED);
2914 if (restart_block) {
2915 /* A failure happened early enough that we know the destination hasn't
2916 * accessed block devices, so we're safe to recover.
2917 */
2918 Error *local_err = NULL;
2919
2920 bdrv_invalidate_cache_all(&local_err);
2921 if (local_err) {
2922 error_report_err(local_err);
2923 }
2924 }
2925 qemu_mutex_unlock_iothread();
2926 return -1;
2927 }
2928
2929 /**
2930 * migration_maybe_pause: Pause if required to by
2931 * migrate_pause_before_switchover called with the iothread locked
2932 * Returns: 0 on success
2933 */
2934 static int migration_maybe_pause(MigrationState *s,
2935 int *current_active_state,
2936 int new_state)
2937 {
2938 if (!migrate_pause_before_switchover()) {
2939 return 0;
2940 }
2941
2942 /* Since leaving this state is not atomic with posting the semaphore
2943 * it's possible that someone could have issued multiple migrate_continue
2944 * and the semaphore is incorrectly positive at this point;
2945 * the docs say it's undefined to reinit a semaphore that's already
2946 * init'd, so use timedwait to eat up any existing posts.
2947 */
2948 while (qemu_sem_timedwait(&s->pause_sem, 1) == 0) {
2949 /* This block intentionally left blank */
2950 }
2951
2952 /*
2953 * If the migration is cancelled when it is in the completion phase,
2954 * the migration state is set to MIGRATION_STATUS_CANCELLING.
2955 * So we don't need to wait a semaphore, otherwise we would always
2956 * wait for the 'pause_sem' semaphore.
2957 */
2958 if (s->state != MIGRATION_STATUS_CANCELLING) {
2959 qemu_mutex_unlock_iothread();
2960 migrate_set_state(&s->state, *current_active_state,
2961 MIGRATION_STATUS_PRE_SWITCHOVER);
2962 qemu_sem_wait(&s->pause_sem);
2963 migrate_set_state(&s->state, MIGRATION_STATUS_PRE_SWITCHOVER,
2964 new_state);
2965 *current_active_state = new_state;
2966 qemu_mutex_lock_iothread();
2967 }
2968
2969 return s->state == new_state ? 0 : -EINVAL;
2970 }
2971
2972 /**
2973 * migration_completion: Used by migration_thread when there's not much left.
2974 * The caller 'breaks' the loop when this returns.
2975 *
2976 * @s: Current migration state
2977 */
2978 static void migration_completion(MigrationState *s)
2979 {
2980 int ret;
2981 int current_active_state = s->state;
2982
2983 if (s->state == MIGRATION_STATUS_ACTIVE) {
2984 qemu_mutex_lock_iothread();
2985 s->downtime_start = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
2986 qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER, NULL);
2987 s->vm_was_running = runstate_is_running();
2988 ret = global_state_store();
2989
2990 if (!ret) {
2991 bool inactivate = !migrate_colo_enabled();
2992 ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
2993 if (ret >= 0) {
2994 ret = migration_maybe_pause(s, &current_active_state,
2995 MIGRATION_STATUS_DEVICE);
2996 }
2997 if (ret >= 0) {
2998 qemu_file_set_rate_limit(s->to_dst_file, INT64_MAX);
2999 ret = qemu_savevm_state_complete_precopy(s->to_dst_file, false,
3000 inactivate);
3001 }
3002 if (inactivate && ret >= 0) {
3003 s->block_inactive = true;
3004 }
3005 }
3006 qemu_mutex_unlock_iothread();
3007
3008 if (ret < 0) {
3009 goto fail;
3010 }
3011 } else if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) {
3012 trace_migration_completion_postcopy_end();
3013
3014 qemu_savevm_state_complete_postcopy(s->to_dst_file);
3015 trace_migration_completion_postcopy_end_after_complete();
3016 }
3017
3018 /*
3019 * If rp was opened we must clean up the thread before
3020 * cleaning everything else up (since if there are no failures
3021 * it will wait for the destination to send it's status in
3022 * a SHUT command).
3023 */
3024 if (s->rp_state.from_dst_file) {
3025 int rp_error;
3026 trace_migration_return_path_end_before();
3027 rp_error = await_return_path_close_on_source(s);
3028 trace_migration_return_path_end_after(rp_error);
3029 if (rp_error) {
3030 goto fail_invalidate;
3031 }
3032 }
3033
3034 if (qemu_file_get_error(s->to_dst_file)) {
3035 trace_migration_completion_file_err();
3036 goto fail_invalidate;
3037 }
3038
3039 if (!migrate_colo_enabled()) {
3040 migrate_set_state(&s->state, current_active_state,
3041 MIGRATION_STATUS_COMPLETED);
3042 }
3043
3044 return;
3045
3046 fail_invalidate:
3047 /* If not doing postcopy, vm_start() will be called: let's regain
3048 * control on images.
3049 */
3050 if (s->state == MIGRATION_STATUS_ACTIVE ||
3051 s->state == MIGRATION_STATUS_DEVICE) {
3052 Error *local_err = NULL;
3053
3054 qemu_mutex_lock_iothread();
3055 bdrv_invalidate_cache_all(&local_err);
3056 if (local_err) {
3057 error_report_err(local_err);
3058 } else {
3059 s->block_inactive = false;
3060 }
3061 qemu_mutex_unlock_iothread();
3062 }
3063
3064 fail:
3065 migrate_set_state(&s->state, current_active_state,
3066 MIGRATION_STATUS_FAILED);
3067 }
3068
3069 bool migrate_colo_enabled(void)
3070 {
3071 MigrationState *s = migrate_get_current();
3072 return s->enabled_capabilities[MIGRATION_CAPABILITY_X_COLO];
3073 }
3074
3075 typedef enum MigThrError {
3076 /* No error detected */
3077 MIG_THR_ERR_NONE = 0,
3078 /* Detected error, but resumed successfully */
3079 MIG_THR_ERR_RECOVERED = 1,
3080 /* Detected fatal error, need to exit */
3081 MIG_THR_ERR_FATAL = 2,
3082 } MigThrError;
3083
3084 static int postcopy_resume_handshake(MigrationState *s)
3085 {
3086 qemu_savevm_send_postcopy_resume(s->to_dst_file);
3087
3088 while (s->state == MIGRATION_STATUS_POSTCOPY_RECOVER) {
3089 qemu_sem_wait(&s->rp_state.rp_sem);
3090 }
3091
3092 if (s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE) {
3093 return 0;
3094 }
3095
3096 return -1;
3097 }
3098
3099 /* Return zero if success, or <0 for error */
3100 static int postcopy_do_resume(MigrationState *s)
3101 {
3102 int ret;
3103
3104 /*
3105 * Call all the resume_prepare() hooks, so that modules can be
3106 * ready for the migration resume.
3107 */
3108 ret = qemu_savevm_state_resume_prepare(s);
3109 if (ret) {
3110 error_report("%s: resume_prepare() failure detected: %d",
3111 __func__, ret);
3112 return ret;
3113 }
3114
3115 /*
3116 * Last handshake with destination on the resume (destination will
3117 * switch to postcopy-active afterwards)
3118 */
3119 ret = postcopy_resume_handshake(s);
3120 if (ret) {
3121 error_report("%s: handshake failed: %d", __func__, ret);
3122 return ret;
3123 }
3124
3125 return 0;
3126 }
3127
3128 /*
3129 * We don't return until we are in a safe state to continue current
3130 * postcopy migration. Returns MIG_THR_ERR_RECOVERED if recovered, or
3131 * MIG_THR_ERR_FATAL if unrecovery failure happened.
3132 */
3133 static MigThrError postcopy_pause(MigrationState *s)
3134 {
3135 assert(s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE);
3136
3137 while (true) {
3138 QEMUFile *file;
3139
3140 migrate_set_state(&s->state, s->state,
3141 MIGRATION_STATUS_POSTCOPY_PAUSED);
3142
3143 /* Current channel is possibly broken. Release it. */
3144 assert(s->to_dst_file);
3145 qemu_mutex_lock(&s->qemu_file_lock);
3146 file = s->to_dst_file;
3147 s->to_dst_file = NULL;
3148 qemu_mutex_unlock(&s->qemu_file_lock);
3149
3150 qemu_file_shutdown(file);
3151 qemu_fclose(file);
3152
3153 error_report("Detected IO failure for postcopy. "
3154 "Migration paused.");
3155
3156 /*
3157 * We wait until things fixed up. Then someone will setup the
3158 * status back for us.
3159 */
3160 while (s->state == MIGRATION_STATUS_POSTCOPY_PAUSED) {
3161 qemu_sem_wait(&s->postcopy_pause_sem);
3162 }
3163
3164 if (s->state == MIGRATION_STATUS_POSTCOPY_RECOVER) {
3165 /* Woken up by a recover procedure. Give it a shot */
3166
3167 /*
3168 * Firstly, let's wake up the return path now, with a new
3169 * return path channel.
3170 */
3171 qemu_sem_post(&s->postcopy_pause_rp_sem);
3172
3173 /* Do the resume logic */
3174 if (postcopy_do_resume(s) == 0) {
3175 /* Let's continue! */
3176 trace_postcopy_pause_continued();
3177 return MIG_THR_ERR_RECOVERED;
3178 } else {
3179 /*
3180 * Something wrong happened during the recovery, let's
3181 * pause again. Pause is always better than throwing
3182 * data away.
3183 */
3184 continue;
3185 }
3186 } else {
3187 /* This is not right... Time to quit. */
3188 return MIG_THR_ERR_FATAL;
3189 }
3190 }
3191 }
3192
3193 static MigThrError migration_detect_error(MigrationState *s)
3194 {
3195 int ret;
3196 int state = s->state;
3197 Error *local_error = NULL;
3198
3199 if (state == MIGRATION_STATUS_CANCELLING ||
3200 state == MIGRATION_STATUS_CANCELLED) {
3201 /* End the migration, but don't set the state to failed */
3202 return MIG_THR_ERR_FATAL;
3203 }
3204
3205 /* Try to detect any file errors */
3206 ret = qemu_file_get_error_obj(s->to_dst_file, &local_error);
3207 if (!ret) {
3208 /* Everything is fine */
3209 assert(!local_error);
3210 return MIG_THR_ERR_NONE;
3211 }
3212
3213 if (local_error) {
3214 migrate_set_error(s, local_error);
3215 error_free(local_error);
3216 }
3217
3218 if (state == MIGRATION_STATUS_POSTCOPY_ACTIVE && ret == -EIO) {
3219 /*
3220 * For postcopy, we allow the network to be down for a
3221 * while. After that, it can be continued by a
3222 * recovery phase.
3223 */
3224 return postcopy_pause(s);
3225 } else {
3226 /*
3227 * For precopy (or postcopy with error outside IO), we fail
3228 * with no time.
3229 */
3230 migrate_set_state(&s->state, state, MIGRATION_STATUS_FAILED);
3231 trace_migration_thread_file_err();
3232
3233 /* Time to stop the migration, now. */
3234 return MIG_THR_ERR_FATAL;
3235 }
3236 }
3237
3238 /* How many bytes have we transferred since the beginning of the migration */
3239 static uint64_t migration_total_bytes(MigrationState *s)
3240 {
3241 return qemu_ftell(s->to_dst_file) + ram_counters.multifd_bytes;
3242 }
3243
3244 static void migration_calculate_complete(MigrationState *s)
3245 {
3246 uint64_t bytes = migration_total_bytes(s);
3247 int64_t end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
3248 int64_t transfer_time;
3249
3250 s->total_time = end_time - s->start_time;
3251 if (!s->downtime) {
3252 /*
3253 * It's still not set, so we are precopy migration. For
3254 * postcopy, downtime is calculated during postcopy_start().
3255 */
3256 s->downtime = end_time - s->downtime_start;
3257 }
3258
3259 transfer_time = s->total_time - s->setup_time;
3260 if (transfer_time) {
3261 s->mbps = ((double) bytes * 8.0) / transfer_time / 1000;
3262 }
3263 }
3264
3265 static void update_iteration_initial_status(MigrationState *s)
3266 {
3267 /*
3268 * Update these three fields at the same time to avoid mismatch info lead
3269 * wrong speed calculation.
3270 */
3271 s->iteration_start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
3272 s->iteration_initial_bytes = migration_total_bytes(s);
3273 s->iteration_initial_pages = ram_get_total_transferred_pages();
3274 }
3275
3276 static void migration_update_counters(MigrationState *s,
3277 int64_t current_time)
3278 {
3279 uint64_t transferred, transferred_pages, time_spent;
3280 uint64_t current_bytes; /* bytes transferred since the beginning */
3281 double bandwidth;
3282
3283 if (current_time < s->iteration_start_time + BUFFER_DELAY) {
3284 return;
3285 }
3286
3287 current_bytes = migration_total_bytes(s);
3288 transferred = current_bytes - s->iteration_initial_bytes;
3289 time_spent = current_time - s->iteration_start_time;
3290 bandwidth = (double)transferred / time_spent;
3291 s->threshold_size = bandwidth * s->parameters.downtime_limit;
3292
3293 s->mbps = (((double) transferred * 8.0) /
3294 ((double) time_spent / 1000.0)) / 1000.0 / 1000.0;
3295
3296 transferred_pages = ram_get_total_transferred_pages() -
3297 s->iteration_initial_pages;
3298 s->pages_per_second = (double) transferred_pages /
3299 (((double) time_spent / 1000.0));
3300
3301 /*
3302 * if we haven't sent anything, we don't want to
3303 * recalculate. 10000 is a small enough number for our purposes
3304 */
3305 if (ram_counters.dirty_pages_rate && transferred > 10000) {
3306 s->expected_downtime = ram_counters.remaining / bandwidth;
3307 }
3308
3309 qemu_file_reset_rate_limit(s->to_dst_file);
3310
3311 update_iteration_initial_status(s);
3312
3313 trace_migrate_transferred(transferred, time_spent,
3314 bandwidth, s->threshold_size);
3315 }
3316
3317 /* Migration thread iteration status */
3318 typedef enum {
3319 MIG_ITERATE_RESUME, /* Resume current iteration */
3320 MIG_ITERATE_SKIP, /* Skip current iteration */
3321 MIG_ITERATE_BREAK, /* Break the loop */
3322 } MigIterateState;
3323
3324 /*
3325 * Return true if continue to the next iteration directly, false
3326 * otherwise.
3327 */
3328 static MigIterateState migration_iteration_run(MigrationState *s)
3329 {
3330 uint64_t pending_size, pend_pre, pend_compat, pend_post;
3331 bool in_postcopy = s->state == MIGRATION_STATUS_POSTCOPY_ACTIVE;
3332
3333 qemu_savevm_state_pending(s->to_dst_file, s->threshold_size, &pend_pre,
3334 &pend_compat, &pend_post);
3335 pending_size = pend_pre + pend_compat + pend_post;
3336
3337 trace_migrate_pending(pending_size, s->threshold_size,
3338 pend_pre, pend_compat, pend_post);
3339
3340 if (pending_size && pending_size >= s->threshold_size) {
3341 /* Still a significant amount to transfer */
3342 if (!in_postcopy && pend_pre <= s->threshold_size &&
3343 qatomic_read(&s->start_postcopy)) {
3344 if (postcopy_start(s)) {
3345 error_report("%s: postcopy failed to start", __func__);
3346 }
3347 return MIG_ITERATE_SKIP;
3348 }
3349 /* Just another iteration step */
3350 qemu_savevm_state_iterate(s->to_dst_file, in_postcopy);
3351 } else {
3352 trace_migration_thread_low_pending(pending_size);
3353 migration_completion(s);
3354 return MIG_ITERATE_BREAK;
3355 }
3356
3357 return MIG_ITERATE_RESUME;
3358 }
3359
3360 static void migration_iteration_finish(MigrationState *s)
3361 {
3362 /* If we enabled cpu throttling for auto-converge, turn it off. */
3363 cpu_throttle_stop();
3364
3365 qemu_mutex_lock_iothread();
3366 switch (s->state) {
3367 case MIGRATION_STATUS_COMPLETED:
3368 migration_calculate_complete(s);
3369 runstate_set(RUN_STATE_POSTMIGRATE);
3370 break;
3371
3372 case MIGRATION_STATUS_ACTIVE:
3373 /*
3374 * We should really assert here, but since it's during
3375 * migration, let's try to reduce the usage of assertions.
3376 */
3377 if (!migrate_colo_enabled()) {
3378 error_report("%s: critical error: calling COLO code without "
3379 "COLO enabled", __func__);
3380 }
3381 migrate_start_colo_process(s);
3382 /*
3383 * Fixme: we will run VM in COLO no matter its old running state.
3384 * After exited COLO, we will keep running.
3385 */
3386 s->vm_was_running = true;
3387 /* Fallthrough */
3388 case MIGRATION_STATUS_FAILED:
3389 case MIGRATION_STATUS_CANCELLED:
3390 case MIGRATION_STATUS_CANCELLING:
3391 if (s->vm_was_running) {
3392 vm_start();
3393 } else {
3394 if (runstate_check(RUN_STATE_FINISH_MIGRATE)) {
3395 runstate_set(RUN_STATE_POSTMIGRATE);
3396 }
3397 }
3398 break;
3399
3400 default:
3401 /* Should not reach here, but if so, forgive the VM. */
3402 error_report("%s: Unknown ending state %d", __func__, s->state);
3403 break;
3404 }
3405 migrate_fd_cleanup_schedule(s);
3406 qemu_mutex_unlock_iothread();
3407 }
3408
3409 void migration_make_urgent_request(void)
3410 {
3411 qemu_sem_post(&migrate_get_current()->rate_limit_sem);
3412 }
3413
3414 void migration_consume_urgent_request(void)
3415 {
3416 qemu_sem_wait(&migrate_get_current()->rate_limit_sem);
3417 }
3418
3419 /* Returns true if the rate limiting was broken by an urgent request */
3420 bool migration_rate_limit(void)
3421 {
3422 int64_t now = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
3423 MigrationState *s = migrate_get_current();
3424
3425 bool urgent = false;
3426 migration_update_counters(s, now);
3427 if (qemu_file_rate_limit(s->to_dst_file)) {
3428
3429 if (qemu_file_get_error(s->to_dst_file)) {
3430 return false;
3431 }
3432 /*
3433 * Wait for a delay to do rate limiting OR
3434 * something urgent to post the semaphore.
3435 */
3436 int ms = s->iteration_start_time + BUFFER_DELAY - now;
3437 trace_migration_rate_limit_pre(ms);
3438 if (qemu_sem_timedwait(&s->rate_limit_sem, ms) == 0) {
3439 /*
3440 * We were woken by one or more urgent things but
3441 * the timedwait will have consumed one of them.
3442 * The service routine for the urgent wake will dec
3443 * the semaphore itself for each item it consumes,