4 * Copyright (c) 2003-2008 Fabrice Bellard
5 * Copyright (c) 2009-2015 Red Hat Inc
8 * Juan Quintela <quintela@redhat.com>
10 * Permission is hereby granted, free of charge, to any person obtaining a copy
11 * of this software and associated documentation files (the "Software"), to deal
12 * in the Software without restriction, including without limitation the rights
13 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
14 * copies of the Software, and to permit persons to whom the Software is
15 * furnished to do so, subject to the following conditions:
17 * The above copyright notice and this permission notice shall be included in
18 * all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
23 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
25 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
29 #include "qemu/osdep.h"
30 #include "hw/boards.h"
32 #include "migration.h"
33 #include "migration/snapshot.h"
34 #include "migration-stats.h"
35 #include "migration/vmstate.h"
36 #include "migration/misc.h"
37 #include "migration/register.h"
38 #include "migration/global_state.h"
39 #include "migration/channel-block.h"
41 #include "qemu-file.h"
43 #include "postcopy-ram.h"
44 #include "qapi/error.h"
45 #include "qapi/qapi-commands-migration.h"
46 #include "qapi/clone-visitor.h"
47 #include "qapi/qapi-builtin-visit.h"
48 #include "qapi/qmp/qerror.h"
49 #include "qemu/error-report.h"
50 #include "sysemu/cpus.h"
51 #include "exec/memory.h"
52 #include "exec/target_page.h"
56 #include "qemu/main-loop.h"
57 #include "block/snapshot.h"
58 #include "qemu/cutils.h"
59 #include "io/channel-buffer.h"
60 #include "io/channel-file.h"
61 #include "sysemu/replay.h"
62 #include "sysemu/runstate.h"
63 #include "sysemu/sysemu.h"
64 #include "sysemu/xen.h"
65 #include "migration/colo.h"
66 #include "qemu/bitmap.h"
67 #include "net/announce.h"
68 #include "qemu/yank.h"
69 #include "yank_functions.h"
70 #include "sysemu/qtest.h"
73 const unsigned int postcopy_ram_discard_version
;
75 /* Subcommands for QEMU_VM_COMMAND */
77 MIG_CMD_INVALID
= 0, /* Must be 0 */
78 MIG_CMD_OPEN_RETURN_PATH
, /* Tell the dest to open the Return path */
79 MIG_CMD_PING
, /* Request a PONG on the RP */
81 MIG_CMD_POSTCOPY_ADVISE
, /* Prior to any page transfers, just
82 warn we might want to do PC */
83 MIG_CMD_POSTCOPY_LISTEN
, /* Start listening for incoming
84 pages as it's running. */
85 MIG_CMD_POSTCOPY_RUN
, /* Start execution */
87 MIG_CMD_POSTCOPY_RAM_DISCARD
, /* A list of pages to discard that
88 were previously sent during
89 precopy but are dirty. */
90 MIG_CMD_PACKAGED
, /* Send a wrapped stream within this stream */
91 MIG_CMD_ENABLE_COLO
, /* Enable COLO */
92 MIG_CMD_POSTCOPY_RESUME
, /* resume postcopy on dest */
93 MIG_CMD_RECV_BITMAP
, /* Request for recved bitmap on dst */
97 #define MAX_VM_CMD_PACKAGED_SIZE UINT32_MAX
98 static struct mig_cmd_args
{
99 ssize_t len
; /* -1 = variable */
102 [MIG_CMD_INVALID
] = { .len
= -1, .name
= "INVALID" },
103 [MIG_CMD_OPEN_RETURN_PATH
] = { .len
= 0, .name
= "OPEN_RETURN_PATH" },
104 [MIG_CMD_PING
] = { .len
= sizeof(uint32_t), .name
= "PING" },
105 [MIG_CMD_POSTCOPY_ADVISE
] = { .len
= -1, .name
= "POSTCOPY_ADVISE" },
106 [MIG_CMD_POSTCOPY_LISTEN
] = { .len
= 0, .name
= "POSTCOPY_LISTEN" },
107 [MIG_CMD_POSTCOPY_RUN
] = { .len
= 0, .name
= "POSTCOPY_RUN" },
108 [MIG_CMD_POSTCOPY_RAM_DISCARD
] = {
109 .len
= -1, .name
= "POSTCOPY_RAM_DISCARD" },
110 [MIG_CMD_POSTCOPY_RESUME
] = { .len
= 0, .name
= "POSTCOPY_RESUME" },
111 [MIG_CMD_PACKAGED
] = { .len
= 4, .name
= "PACKAGED" },
112 [MIG_CMD_RECV_BITMAP
] = { .len
= -1, .name
= "RECV_BITMAP" },
113 [MIG_CMD_MAX
] = { .len
= -1, .name
= "MAX" },
116 /* Note for MIG_CMD_POSTCOPY_ADVISE:
117 * The format of arguments is depending on postcopy mode:
118 * - postcopy RAM only
119 * uint64_t host page size
120 * uint64_t target page size
122 * - postcopy RAM and postcopy dirty bitmaps
123 * format is the same as for postcopy RAM only
125 * - postcopy dirty bitmaps only
126 * Nothing. Command length field is 0.
128 * Be careful: adding a new postcopy entity with some other parameters should
129 * not break format self-description ability. Good way is to introduce some
130 * generic extendable format with an exception for two old entities.
133 /***********************************************************/
134 /* savevm/loadvm support */
136 static QEMUFile
*qemu_fopen_bdrv(BlockDriverState
*bs
, int is_writable
)
139 return qemu_file_new_output(QIO_CHANNEL(qio_channel_block_new(bs
)));
141 return qemu_file_new_input(QIO_CHANNEL(qio_channel_block_new(bs
)));
146 /* QEMUFile timer support.
147 * Not in qemu-file.c to not add qemu-timer.c as dependency to qemu-file.c
150 void timer_put(QEMUFile
*f
, QEMUTimer
*ts
)
152 uint64_t expire_time
;
154 expire_time
= timer_expire_time_ns(ts
);
155 qemu_put_be64(f
, expire_time
);
158 void timer_get(QEMUFile
*f
, QEMUTimer
*ts
)
160 uint64_t expire_time
;
162 expire_time
= qemu_get_be64(f
);
163 if (expire_time
!= -1) {
164 timer_mod_ns(ts
, expire_time
);
171 /* VMState timer support.
172 * Not in vmstate.c to not add qemu-timer.c as dependency to vmstate.c
175 static int get_timer(QEMUFile
*f
, void *pv
, size_t size
,
176 const VMStateField
*field
)
183 static int put_timer(QEMUFile
*f
, void *pv
, size_t size
,
184 const VMStateField
*field
, JSONWriter
*vmdesc
)
192 const VMStateInfo vmstate_info_timer
= {
199 typedef struct CompatEntry
{
204 typedef struct SaveStateEntry
{
205 QTAILQ_ENTRY(SaveStateEntry
) entry
;
207 uint32_t instance_id
;
210 /* version id read from the stream */
213 /* section id read from the stream */
215 const SaveVMHandlers
*ops
;
216 const VMStateDescription
*vmsd
;
222 typedef struct SaveState
{
223 QTAILQ_HEAD(, SaveStateEntry
) handlers
;
224 SaveStateEntry
*handler_pri_head
[MIG_PRI_MAX
+ 1];
225 int global_section_id
;
228 uint32_t target_page_bits
;
230 MigrationCapability
*capabilities
;
234 static SaveState savevm_state
= {
235 .handlers
= QTAILQ_HEAD_INITIALIZER(savevm_state
.handlers
),
236 .handler_pri_head
= { [MIG_PRI_DEFAULT
... MIG_PRI_MAX
] = NULL
},
237 .global_section_id
= 0,
240 static SaveStateEntry
*find_se(const char *idstr
, uint32_t instance_id
);
242 static bool should_validate_capability(int capability
)
244 assert(capability
>= 0 && capability
< MIGRATION_CAPABILITY__MAX
);
245 /* Validate only new capabilities to keep compatibility. */
246 switch (capability
) {
247 case MIGRATION_CAPABILITY_X_IGNORE_SHARED
:
248 case MIGRATION_CAPABILITY_MAPPED_RAM
:
255 static uint32_t get_validatable_capabilities_count(void)
257 MigrationState
*s
= migrate_get_current();
260 for (i
= 0; i
< MIGRATION_CAPABILITY__MAX
; i
++) {
261 if (should_validate_capability(i
) && s
->capabilities
[i
]) {
268 static int configuration_pre_save(void *opaque
)
270 SaveState
*state
= opaque
;
271 const char *current_name
= MACHINE_GET_CLASS(current_machine
)->name
;
272 MigrationState
*s
= migrate_get_current();
275 state
->len
= strlen(current_name
);
276 state
->name
= current_name
;
277 state
->target_page_bits
= qemu_target_page_bits();
279 state
->caps_count
= get_validatable_capabilities_count();
280 state
->capabilities
= g_renew(MigrationCapability
, state
->capabilities
,
282 for (i
= j
= 0; i
< MIGRATION_CAPABILITY__MAX
; i
++) {
283 if (should_validate_capability(i
) && s
->capabilities
[i
]) {
284 state
->capabilities
[j
++] = i
;
287 state
->uuid
= qemu_uuid
;
292 static int configuration_post_save(void *opaque
)
294 SaveState
*state
= opaque
;
296 g_free(state
->capabilities
);
297 state
->capabilities
= NULL
;
298 state
->caps_count
= 0;
302 static int configuration_pre_load(void *opaque
)
304 SaveState
*state
= opaque
;
306 /* If there is no target-page-bits subsection it means the source
307 * predates the variable-target-page-bits support and is using the
308 * minimum possible value for this CPU.
310 state
->target_page_bits
= qemu_target_page_bits_min();
314 static bool configuration_validate_capabilities(SaveState
*state
)
317 MigrationState
*s
= migrate_get_current();
318 unsigned long *source_caps_bm
;
321 source_caps_bm
= bitmap_new(MIGRATION_CAPABILITY__MAX
);
322 for (i
= 0; i
< state
->caps_count
; i
++) {
323 MigrationCapability capability
= state
->capabilities
[i
];
324 set_bit(capability
, source_caps_bm
);
327 for (i
= 0; i
< MIGRATION_CAPABILITY__MAX
; i
++) {
328 bool source_state
, target_state
;
329 if (!should_validate_capability(i
)) {
332 source_state
= test_bit(i
, source_caps_bm
);
333 target_state
= s
->capabilities
[i
];
334 if (source_state
!= target_state
) {
335 error_report("Capability %s is %s, but received capability is %s",
336 MigrationCapability_str(i
),
337 target_state
? "on" : "off",
338 source_state
? "on" : "off");
340 /* Don't break here to report all failed capabilities */
344 g_free(source_caps_bm
);
348 static int configuration_post_load(void *opaque
, int version_id
)
350 SaveState
*state
= opaque
;
351 const char *current_name
= MACHINE_GET_CLASS(current_machine
)->name
;
354 if (strncmp(state
->name
, current_name
, state
->len
) != 0) {
355 error_report("Machine type received is '%.*s' and local is '%s'",
356 (int) state
->len
, state
->name
, current_name
);
361 if (state
->target_page_bits
!= qemu_target_page_bits()) {
362 error_report("Received TARGET_PAGE_BITS is %d but local is %d",
363 state
->target_page_bits
, qemu_target_page_bits());
368 if (!configuration_validate_capabilities(state
)) {
374 g_free((void *)state
->name
);
377 g_free(state
->capabilities
);
378 state
->capabilities
= NULL
;
379 state
->caps_count
= 0;
384 static int get_capability(QEMUFile
*f
, void *pv
, size_t size
,
385 const VMStateField
*field
)
387 MigrationCapability
*capability
= pv
;
388 char capability_str
[UINT8_MAX
+ 1];
392 len
= qemu_get_byte(f
);
393 qemu_get_buffer(f
, (uint8_t *)capability_str
, len
);
394 capability_str
[len
] = '\0';
395 for (i
= 0; i
< MIGRATION_CAPABILITY__MAX
; i
++) {
396 if (!strcmp(MigrationCapability_str(i
), capability_str
)) {
401 error_report("Received unknown capability %s", capability_str
);
405 static int put_capability(QEMUFile
*f
, void *pv
, size_t size
,
406 const VMStateField
*field
, JSONWriter
*vmdesc
)
408 MigrationCapability
*capability
= pv
;
409 const char *capability_str
= MigrationCapability_str(*capability
);
410 size_t len
= strlen(capability_str
);
411 assert(len
<= UINT8_MAX
);
413 qemu_put_byte(f
, len
);
414 qemu_put_buffer(f
, (uint8_t *)capability_str
, len
);
418 static const VMStateInfo vmstate_info_capability
= {
419 .name
= "capability",
420 .get
= get_capability
,
421 .put
= put_capability
,
424 /* The target-page-bits subsection is present only if the
425 * target page size is not the same as the default (ie the
426 * minimum page size for a variable-page-size guest CPU).
427 * If it is present then it contains the actual target page
428 * bits for the machine, and migration will fail if the
429 * two ends don't agree about it.
431 static bool vmstate_target_page_bits_needed(void *opaque
)
433 return qemu_target_page_bits()
434 > qemu_target_page_bits_min();
437 static const VMStateDescription vmstate_target_page_bits
= {
438 .name
= "configuration/target-page-bits",
440 .minimum_version_id
= 1,
441 .needed
= vmstate_target_page_bits_needed
,
442 .fields
= (const VMStateField
[]) {
443 VMSTATE_UINT32(target_page_bits
, SaveState
),
444 VMSTATE_END_OF_LIST()
448 static bool vmstate_capabilites_needed(void *opaque
)
450 return get_validatable_capabilities_count() > 0;
453 static const VMStateDescription vmstate_capabilites
= {
454 .name
= "configuration/capabilities",
456 .minimum_version_id
= 1,
457 .needed
= vmstate_capabilites_needed
,
458 .fields
= (const VMStateField
[]) {
459 VMSTATE_UINT32_V(caps_count
, SaveState
, 1),
460 VMSTATE_VARRAY_UINT32_ALLOC(capabilities
, SaveState
, caps_count
, 1,
461 vmstate_info_capability
,
462 MigrationCapability
),
463 VMSTATE_END_OF_LIST()
467 static bool vmstate_uuid_needed(void *opaque
)
469 return qemu_uuid_set
&& migrate_validate_uuid();
472 static int vmstate_uuid_post_load(void *opaque
, int version_id
)
474 SaveState
*state
= opaque
;
475 char uuid_src
[UUID_STR_LEN
];
476 char uuid_dst
[UUID_STR_LEN
];
478 if (!qemu_uuid_set
) {
480 * It's warning because user might not know UUID in some cases,
481 * e.g. load an old snapshot
483 qemu_uuid_unparse(&state
->uuid
, uuid_src
);
484 warn_report("UUID is received %s, but local uuid isn't set",
488 if (!qemu_uuid_is_equal(&state
->uuid
, &qemu_uuid
)) {
489 qemu_uuid_unparse(&state
->uuid
, uuid_src
);
490 qemu_uuid_unparse(&qemu_uuid
, uuid_dst
);
491 error_report("UUID received is %s and local is %s", uuid_src
, uuid_dst
);
497 static const VMStateDescription vmstate_uuid
= {
498 .name
= "configuration/uuid",
500 .minimum_version_id
= 1,
501 .needed
= vmstate_uuid_needed
,
502 .post_load
= vmstate_uuid_post_load
,
503 .fields
= (const VMStateField
[]) {
504 VMSTATE_UINT8_ARRAY_V(uuid
.data
, SaveState
, sizeof(QemuUUID
), 1),
505 VMSTATE_END_OF_LIST()
509 static const VMStateDescription vmstate_configuration
= {
510 .name
= "configuration",
512 .pre_load
= configuration_pre_load
,
513 .post_load
= configuration_post_load
,
514 .pre_save
= configuration_pre_save
,
515 .post_save
= configuration_post_save
,
516 .fields
= (const VMStateField
[]) {
517 VMSTATE_UINT32(len
, SaveState
),
518 VMSTATE_VBUFFER_ALLOC_UINT32(name
, SaveState
, 0, NULL
, len
),
519 VMSTATE_END_OF_LIST()
521 .subsections
= (const VMStateDescription
* const []) {
522 &vmstate_target_page_bits
,
523 &vmstate_capabilites
,
529 static void dump_vmstate_vmsd(FILE *out_file
,
530 const VMStateDescription
*vmsd
, int indent
,
533 static void dump_vmstate_vmsf(FILE *out_file
, const VMStateField
*field
,
536 fprintf(out_file
, "%*s{\n", indent
, "");
538 fprintf(out_file
, "%*s\"field\": \"%s\",\n", indent
, "", field
->name
);
539 fprintf(out_file
, "%*s\"version_id\": %d,\n", indent
, "",
541 fprintf(out_file
, "%*s\"field_exists\": %s,\n", indent
, "",
542 field
->field_exists
? "true" : "false");
543 if (field
->flags
& VMS_ARRAY
) {
544 fprintf(out_file
, "%*s\"num\": %d,\n", indent
, "", field
->num
);
546 fprintf(out_file
, "%*s\"size\": %zu", indent
, "", field
->size
);
547 if (field
->vmsd
!= NULL
) {
548 fprintf(out_file
, ",\n");
549 dump_vmstate_vmsd(out_file
, field
->vmsd
, indent
, false);
551 fprintf(out_file
, "\n%*s}", indent
- 2, "");
554 static void dump_vmstate_vmss(FILE *out_file
,
555 const VMStateDescription
*subsection
,
558 if (subsection
!= NULL
) {
559 dump_vmstate_vmsd(out_file
, subsection
, indent
, true);
563 static void dump_vmstate_vmsd(FILE *out_file
,
564 const VMStateDescription
*vmsd
, int indent
,
568 fprintf(out_file
, "%*s{\n", indent
, "");
570 fprintf(out_file
, "%*s\"%s\": {\n", indent
, "", "Description");
573 fprintf(out_file
, "%*s\"name\": \"%s\",\n", indent
, "", vmsd
->name
);
574 fprintf(out_file
, "%*s\"version_id\": %d,\n", indent
, "",
576 fprintf(out_file
, "%*s\"minimum_version_id\": %d", indent
, "",
577 vmsd
->minimum_version_id
);
578 if (vmsd
->fields
!= NULL
) {
579 const VMStateField
*field
= vmsd
->fields
;
582 fprintf(out_file
, ",\n%*s\"Fields\": [\n", indent
, "");
584 while (field
->name
!= NULL
) {
585 if (field
->flags
& VMS_MUST_EXIST
) {
586 /* Ignore VMSTATE_VALIDATE bits; these don't get migrated */
591 fprintf(out_file
, ",\n");
593 dump_vmstate_vmsf(out_file
, field
, indent
+ 2);
597 assert(field
->flags
== VMS_END
);
598 fprintf(out_file
, "\n%*s]", indent
, "");
600 if (vmsd
->subsections
!= NULL
) {
601 const VMStateDescription
* const *subsection
= vmsd
->subsections
;
604 fprintf(out_file
, ",\n%*s\"Subsections\": [\n", indent
, "");
606 while (*subsection
!= NULL
) {
608 fprintf(out_file
, ",\n");
610 dump_vmstate_vmss(out_file
, *subsection
, indent
+ 2);
614 fprintf(out_file
, "\n%*s]", indent
, "");
616 fprintf(out_file
, "\n%*s}", indent
- 2, "");
619 static void dump_machine_type(FILE *out_file
)
623 mc
= MACHINE_GET_CLASS(current_machine
);
625 fprintf(out_file
, " \"vmschkmachine\": {\n");
626 fprintf(out_file
, " \"Name\": \"%s\"\n", mc
->name
);
627 fprintf(out_file
, " },\n");
630 void dump_vmstate_json_to_file(FILE *out_file
)
635 fprintf(out_file
, "{\n");
636 dump_machine_type(out_file
);
639 list
= object_class_get_list(TYPE_DEVICE
, true);
640 for (elt
= list
; elt
; elt
= elt
->next
) {
641 DeviceClass
*dc
= OBJECT_CLASS_CHECK(DeviceClass
, elt
->data
,
651 fprintf(out_file
, ",\n");
653 name
= object_class_get_name(OBJECT_CLASS(dc
));
654 fprintf(out_file
, "%*s\"%s\": {\n", indent
, "", name
);
656 fprintf(out_file
, "%*s\"Name\": \"%s\",\n", indent
, "", name
);
657 fprintf(out_file
, "%*s\"version_id\": %d,\n", indent
, "",
658 dc
->vmsd
->version_id
);
659 fprintf(out_file
, "%*s\"minimum_version_id\": %d,\n", indent
, "",
660 dc
->vmsd
->minimum_version_id
);
662 dump_vmstate_vmsd(out_file
, dc
->vmsd
, indent
, false);
664 fprintf(out_file
, "\n%*s}", indent
- 2, "");
667 fprintf(out_file
, "\n}\n");
672 static uint32_t calculate_new_instance_id(const char *idstr
)
675 uint32_t instance_id
= 0;
677 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
678 if (strcmp(idstr
, se
->idstr
) == 0
679 && instance_id
<= se
->instance_id
) {
680 instance_id
= se
->instance_id
+ 1;
683 /* Make sure we never loop over without being noticed */
684 assert(instance_id
!= VMSTATE_INSTANCE_ID_ANY
);
688 static int calculate_compat_instance_id(const char *idstr
)
693 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
698 if (strcmp(idstr
, se
->compat
->idstr
) == 0
699 && instance_id
<= se
->compat
->instance_id
) {
700 instance_id
= se
->compat
->instance_id
+ 1;
706 static inline MigrationPriority
save_state_priority(SaveStateEntry
*se
)
709 return se
->vmsd
->priority
;
711 return MIG_PRI_DEFAULT
;
714 static void savevm_state_handler_insert(SaveStateEntry
*nse
)
716 MigrationPriority priority
= save_state_priority(nse
);
720 assert(priority
<= MIG_PRI_MAX
);
723 * This should never happen otherwise migration will probably fail
724 * silently somewhere because we can be wrongly applying one
725 * object properties upon another one. Bail out ASAP.
727 if (find_se(nse
->idstr
, nse
->instance_id
)) {
728 error_report("%s: Detected duplicate SaveStateEntry: "
729 "id=%s, instance_id=0x%"PRIx32
, __func__
,
730 nse
->idstr
, nse
->instance_id
);
734 for (i
= priority
- 1; i
>= 0; i
--) {
735 se
= savevm_state
.handler_pri_head
[i
];
737 assert(save_state_priority(se
) < priority
);
743 QTAILQ_INSERT_BEFORE(se
, nse
, entry
);
745 QTAILQ_INSERT_TAIL(&savevm_state
.handlers
, nse
, entry
);
748 if (savevm_state
.handler_pri_head
[priority
] == NULL
) {
749 savevm_state
.handler_pri_head
[priority
] = nse
;
753 static void savevm_state_handler_remove(SaveStateEntry
*se
)
755 SaveStateEntry
*next
;
756 MigrationPriority priority
= save_state_priority(se
);
758 if (se
== savevm_state
.handler_pri_head
[priority
]) {
759 next
= QTAILQ_NEXT(se
, entry
);
760 if (next
!= NULL
&& save_state_priority(next
) == priority
) {
761 savevm_state
.handler_pri_head
[priority
] = next
;
763 savevm_state
.handler_pri_head
[priority
] = NULL
;
766 QTAILQ_REMOVE(&savevm_state
.handlers
, se
, entry
);
769 /* TODO: Individual devices generally have very little idea about the rest
770 of the system, so instance_id should be removed/replaced.
771 Meanwhile pass -1 as instance_id if you do not already have a clearly
772 distinguishing id for all instances of your device class. */
773 int register_savevm_live(const char *idstr
,
774 uint32_t instance_id
,
776 const SaveVMHandlers
*ops
,
781 se
= g_new0(SaveStateEntry
, 1);
782 se
->version_id
= version_id
;
783 se
->section_id
= savevm_state
.global_section_id
++;
787 /* if this is a live_savem then set is_ram */
788 if (ops
->save_setup
!= NULL
) {
792 pstrcat(se
->idstr
, sizeof(se
->idstr
), idstr
);
794 if (instance_id
== VMSTATE_INSTANCE_ID_ANY
) {
795 se
->instance_id
= calculate_new_instance_id(se
->idstr
);
797 se
->instance_id
= instance_id
;
799 assert(!se
->compat
|| se
->instance_id
== 0);
800 savevm_state_handler_insert(se
);
804 void unregister_savevm(VMStateIf
*obj
, const char *idstr
, void *opaque
)
806 SaveStateEntry
*se
, *new_se
;
810 char *oid
= vmstate_if_get_id(obj
);
812 pstrcpy(id
, sizeof(id
), oid
);
813 pstrcat(id
, sizeof(id
), "/");
817 pstrcat(id
, sizeof(id
), idstr
);
819 QTAILQ_FOREACH_SAFE(se
, &savevm_state
.handlers
, entry
, new_se
) {
820 if (strcmp(se
->idstr
, id
) == 0 && se
->opaque
== opaque
) {
821 savevm_state_handler_remove(se
);
829 * Perform some basic checks on vmsd's at registration
832 static void vmstate_check(const VMStateDescription
*vmsd
)
834 const VMStateField
*field
= vmsd
->fields
;
835 const VMStateDescription
* const *subsection
= vmsd
->subsections
;
838 while (field
->name
) {
839 if (field
->flags
& (VMS_STRUCT
| VMS_VSTRUCT
)) {
840 /* Recurse to sub structures */
841 vmstate_check(field
->vmsd
);
846 /* Check for the end of field list canary */
847 if (field
->flags
!= VMS_END
) {
848 error_report("VMSTATE not ending with VMS_END: %s", vmsd
->name
);
849 g_assert_not_reached();
853 while (subsection
&& *subsection
) {
855 * The name of a subsection should start with the name of the
858 assert(!strncmp(vmsd
->name
, (*subsection
)->name
, strlen(vmsd
->name
)));
859 vmstate_check(*subsection
);
865 * See comment in hw/intc/xics.c:icp_realize()
867 * This function can be removed when
868 * pre_2_10_vmstate_register_dummy_icp() is removed.
870 int vmstate_replace_hack_for_ppc(VMStateIf
*obj
, int instance_id
,
871 const VMStateDescription
*vmsd
,
874 SaveStateEntry
*se
= find_se(vmsd
->name
, instance_id
);
877 savevm_state_handler_remove(se
);
879 return vmstate_register(obj
, instance_id
, vmsd
, opaque
);
882 int vmstate_register_with_alias_id(VMStateIf
*obj
, uint32_t instance_id
,
883 const VMStateDescription
*vmsd
,
884 void *opaque
, int alias_id
,
885 int required_for_version
,
890 /* If this triggers, alias support can be dropped for the vmsd. */
891 assert(alias_id
== -1 || required_for_version
>= vmsd
->minimum_version_id
);
893 se
= g_new0(SaveStateEntry
, 1);
894 se
->version_id
= vmsd
->version_id
;
895 se
->section_id
= savevm_state
.global_section_id
++;
898 se
->alias_id
= alias_id
;
901 char *id
= vmstate_if_get_id(obj
);
903 if (snprintf(se
->idstr
, sizeof(se
->idstr
), "%s/", id
) >=
905 error_setg(errp
, "Path too long for VMState (%s)", id
);
913 se
->compat
= g_new0(CompatEntry
, 1);
914 pstrcpy(se
->compat
->idstr
, sizeof(se
->compat
->idstr
), vmsd
->name
);
915 se
->compat
->instance_id
= instance_id
== VMSTATE_INSTANCE_ID_ANY
?
916 calculate_compat_instance_id(vmsd
->name
) : instance_id
;
917 instance_id
= VMSTATE_INSTANCE_ID_ANY
;
920 pstrcat(se
->idstr
, sizeof(se
->idstr
), vmsd
->name
);
922 if (instance_id
== VMSTATE_INSTANCE_ID_ANY
) {
923 se
->instance_id
= calculate_new_instance_id(se
->idstr
);
925 se
->instance_id
= instance_id
;
928 /* Perform a recursive sanity check during the test runs */
929 if (qtest_enabled()) {
932 assert(!se
->compat
|| se
->instance_id
== 0);
933 savevm_state_handler_insert(se
);
937 void vmstate_unregister(VMStateIf
*obj
, const VMStateDescription
*vmsd
,
940 SaveStateEntry
*se
, *new_se
;
942 QTAILQ_FOREACH_SAFE(se
, &savevm_state
.handlers
, entry
, new_se
) {
943 if (se
->vmsd
== vmsd
&& se
->opaque
== opaque
) {
944 savevm_state_handler_remove(se
);
951 static int vmstate_load(QEMUFile
*f
, SaveStateEntry
*se
)
953 trace_vmstate_load(se
->idstr
, se
->vmsd
? se
->vmsd
->name
: "(old)");
954 if (!se
->vmsd
) { /* Old style */
955 return se
->ops
->load_state(f
, se
->opaque
, se
->load_version_id
);
957 return vmstate_load_state(f
, se
->vmsd
, se
->opaque
, se
->load_version_id
);
960 static void vmstate_save_old_style(QEMUFile
*f
, SaveStateEntry
*se
,
963 uint64_t old_offset
= qemu_file_transferred(f
);
964 se
->ops
->save_state(f
, se
->opaque
);
965 uint64_t size
= qemu_file_transferred(f
) - old_offset
;
968 json_writer_int64(vmdesc
, "size", size
);
969 json_writer_start_array(vmdesc
, "fields");
970 json_writer_start_object(vmdesc
, NULL
);
971 json_writer_str(vmdesc
, "name", "data");
972 json_writer_int64(vmdesc
, "size", size
);
973 json_writer_str(vmdesc
, "type", "buffer");
974 json_writer_end_object(vmdesc
);
975 json_writer_end_array(vmdesc
);
980 * Write the header for device section (QEMU_VM_SECTION START/END/PART/FULL)
982 static void save_section_header(QEMUFile
*f
, SaveStateEntry
*se
,
983 uint8_t section_type
)
985 qemu_put_byte(f
, section_type
);
986 qemu_put_be32(f
, se
->section_id
);
988 if (section_type
== QEMU_VM_SECTION_FULL
||
989 section_type
== QEMU_VM_SECTION_START
) {
991 size_t len
= strlen(se
->idstr
);
992 qemu_put_byte(f
, len
);
993 qemu_put_buffer(f
, (uint8_t *)se
->idstr
, len
);
995 qemu_put_be32(f
, se
->instance_id
);
996 qemu_put_be32(f
, se
->version_id
);
1001 * Write a footer onto device sections that catches cases misformatted device
1004 static void save_section_footer(QEMUFile
*f
, SaveStateEntry
*se
)
1006 if (migrate_get_current()->send_section_footer
) {
1007 qemu_put_byte(f
, QEMU_VM_SECTION_FOOTER
);
1008 qemu_put_be32(f
, se
->section_id
);
1012 static int vmstate_save(QEMUFile
*f
, SaveStateEntry
*se
, JSONWriter
*vmdesc
,
1017 if ((!se
->ops
|| !se
->ops
->save_state
) && !se
->vmsd
) {
1020 if (se
->vmsd
&& !vmstate_section_needed(se
->vmsd
, se
->opaque
)) {
1021 trace_savevm_section_skip(se
->idstr
, se
->section_id
);
1025 trace_savevm_section_start(se
->idstr
, se
->section_id
);
1026 save_section_header(f
, se
, QEMU_VM_SECTION_FULL
);
1028 json_writer_start_object(vmdesc
, NULL
);
1029 json_writer_str(vmdesc
, "name", se
->idstr
);
1030 json_writer_int64(vmdesc
, "instance_id", se
->instance_id
);
1033 trace_vmstate_save(se
->idstr
, se
->vmsd
? se
->vmsd
->name
: "(old)");
1035 vmstate_save_old_style(f
, se
, vmdesc
);
1037 ret
= vmstate_save_state_with_err(f
, se
->vmsd
, se
->opaque
, vmdesc
,
1044 trace_savevm_section_end(se
->idstr
, se
->section_id
, 0);
1045 save_section_footer(f
, se
);
1047 json_writer_end_object(vmdesc
);
1052 * qemu_savevm_command_send: Send a 'QEMU_VM_COMMAND' type element with the
1053 * command and associated data.
1055 * @f: File to send command on
1056 * @command: Command type to send
1057 * @len: Length of associated data
1058 * @data: Data associated with command.
1060 static void qemu_savevm_command_send(QEMUFile
*f
,
1061 enum qemu_vm_cmd command
,
1065 trace_savevm_command_send(command
, len
);
1066 qemu_put_byte(f
, QEMU_VM_COMMAND
);
1067 qemu_put_be16(f
, (uint16_t)command
);
1068 qemu_put_be16(f
, len
);
1069 qemu_put_buffer(f
, data
, len
);
1073 void qemu_savevm_send_colo_enable(QEMUFile
*f
)
1075 trace_savevm_send_colo_enable();
1076 qemu_savevm_command_send(f
, MIG_CMD_ENABLE_COLO
, 0, NULL
);
1079 void qemu_savevm_send_ping(QEMUFile
*f
, uint32_t value
)
1083 trace_savevm_send_ping(value
);
1084 buf
= cpu_to_be32(value
);
1085 qemu_savevm_command_send(f
, MIG_CMD_PING
, sizeof(value
), (uint8_t *)&buf
);
1088 void qemu_savevm_send_open_return_path(QEMUFile
*f
)
1090 trace_savevm_send_open_return_path();
1091 qemu_savevm_command_send(f
, MIG_CMD_OPEN_RETURN_PATH
, 0, NULL
);
1094 /* We have a buffer of data to send; we don't want that all to be loaded
1095 * by the command itself, so the command contains just the length of the
1096 * extra buffer that we then send straight after it.
1097 * TODO: Must be a better way to organise that
1103 int qemu_savevm_send_packaged(QEMUFile
*f
, const uint8_t *buf
, size_t len
)
1106 MigrationState
*ms
= migrate_get_current();
1107 Error
*local_err
= NULL
;
1109 if (len
> MAX_VM_CMD_PACKAGED_SIZE
) {
1110 error_setg(&local_err
, "%s: Unreasonably large packaged state: %zu",
1112 migrate_set_error(ms
, local_err
);
1113 error_report_err(local_err
);
1117 tmp
= cpu_to_be32(len
);
1119 trace_qemu_savevm_send_packaged();
1120 qemu_savevm_command_send(f
, MIG_CMD_PACKAGED
, 4, (uint8_t *)&tmp
);
1122 qemu_put_buffer(f
, buf
, len
);
1127 /* Send prior to any postcopy transfer */
1128 void qemu_savevm_send_postcopy_advise(QEMUFile
*f
)
1130 if (migrate_postcopy_ram()) {
1132 tmp
[0] = cpu_to_be64(ram_pagesize_summary());
1133 tmp
[1] = cpu_to_be64(qemu_target_page_size());
1135 trace_qemu_savevm_send_postcopy_advise();
1136 qemu_savevm_command_send(f
, MIG_CMD_POSTCOPY_ADVISE
,
1137 16, (uint8_t *)tmp
);
1139 qemu_savevm_command_send(f
, MIG_CMD_POSTCOPY_ADVISE
, 0, NULL
);
1143 /* Sent prior to starting the destination running in postcopy, discard pages
1144 * that have already been sent but redirtied on the source.
1145 * CMD_POSTCOPY_RAM_DISCARD consist of:
1147 * byte Length of name field (not including 0)
1148 * n x byte RAM block name
1149 * byte 0 terminator (just for safety)
1150 * n x Byte ranges within the named RAMBlock
1151 * be64 Start of the range
1154 * name: RAMBlock name that these entries are part of
1155 * len: Number of page entries
1156 * start_list: 'len' addresses
1157 * length_list: 'len' addresses
1160 void qemu_savevm_send_postcopy_ram_discard(QEMUFile
*f
, const char *name
,
1162 uint64_t *start_list
,
1163 uint64_t *length_list
)
1168 size_t name_len
= strlen(name
);
1170 trace_qemu_savevm_send_postcopy_ram_discard(name
, len
);
1171 assert(name_len
< 256);
1172 buf
= g_malloc0(1 + 1 + name_len
+ 1 + (8 + 8) * len
);
1173 buf
[0] = postcopy_ram_discard_version
;
1175 memcpy(buf
+ 2, name
, name_len
);
1176 tmplen
= 2 + name_len
;
1177 buf
[tmplen
++] = '\0';
1179 for (t
= 0; t
< len
; t
++) {
1180 stq_be_p(buf
+ tmplen
, start_list
[t
]);
1182 stq_be_p(buf
+ tmplen
, length_list
[t
]);
1185 qemu_savevm_command_send(f
, MIG_CMD_POSTCOPY_RAM_DISCARD
, tmplen
, buf
);
1189 /* Get the destination into a state where it can receive postcopy data. */
1190 void qemu_savevm_send_postcopy_listen(QEMUFile
*f
)
1192 trace_savevm_send_postcopy_listen();
1193 qemu_savevm_command_send(f
, MIG_CMD_POSTCOPY_LISTEN
, 0, NULL
);
1196 /* Kick the destination into running */
1197 void qemu_savevm_send_postcopy_run(QEMUFile
*f
)
1199 trace_savevm_send_postcopy_run();
1200 qemu_savevm_command_send(f
, MIG_CMD_POSTCOPY_RUN
, 0, NULL
);
1203 void qemu_savevm_send_postcopy_resume(QEMUFile
*f
)
1205 trace_savevm_send_postcopy_resume();
1206 qemu_savevm_command_send(f
, MIG_CMD_POSTCOPY_RESUME
, 0, NULL
);
1209 void qemu_savevm_send_recv_bitmap(QEMUFile
*f
, char *block_name
)
1214 trace_savevm_send_recv_bitmap(block_name
);
1216 buf
[0] = len
= strlen(block_name
);
1217 memcpy(buf
+ 1, block_name
, len
);
1219 qemu_savevm_command_send(f
, MIG_CMD_RECV_BITMAP
, len
+ 1, (uint8_t *)buf
);
1222 bool qemu_savevm_state_blocked(Error
**errp
)
1226 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1227 if (se
->vmsd
&& se
->vmsd
->unmigratable
) {
1228 error_setg(errp
, "State blocked by non-migratable device '%s'",
1236 void qemu_savevm_non_migratable_list(strList
**reasons
)
1240 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1241 if (se
->vmsd
&& se
->vmsd
->unmigratable
) {
1242 QAPI_LIST_PREPEND(*reasons
,
1243 g_strdup_printf("non-migratable device: %s",
1249 void qemu_savevm_state_header(QEMUFile
*f
)
1251 MigrationState
*s
= migrate_get_current();
1253 s
->vmdesc
= json_writer_new(false);
1255 trace_savevm_state_header();
1256 qemu_put_be32(f
, QEMU_VM_FILE_MAGIC
);
1257 qemu_put_be32(f
, QEMU_VM_FILE_VERSION
);
1259 if (s
->send_configuration
) {
1260 qemu_put_byte(f
, QEMU_VM_CONFIGURATION
);
1263 * This starts the main json object and is paired with the
1264 * json_writer_end_object in
1265 * qemu_savevm_state_complete_precopy_non_iterable
1267 json_writer_start_object(s
->vmdesc
, NULL
);
1269 json_writer_start_object(s
->vmdesc
, "configuration");
1270 vmstate_save_state(f
, &vmstate_configuration
, &savevm_state
, s
->vmdesc
);
1271 json_writer_end_object(s
->vmdesc
);
1275 bool qemu_savevm_state_guest_unplug_pending(void)
1279 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1280 if (se
->vmsd
&& se
->vmsd
->dev_unplug_pending
&&
1281 se
->vmsd
->dev_unplug_pending(se
->opaque
)) {
1289 int qemu_savevm_state_prepare(Error
**errp
)
1294 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1295 if (!se
->ops
|| !se
->ops
->save_prepare
) {
1298 if (se
->ops
->is_active
) {
1299 if (!se
->ops
->is_active(se
->opaque
)) {
1304 ret
= se
->ops
->save_prepare(se
->opaque
, errp
);
1313 int qemu_savevm_state_setup(QEMUFile
*f
, Error
**errp
)
1316 MigrationState
*ms
= migrate_get_current();
1320 json_writer_int64(ms
->vmdesc
, "page_size", qemu_target_page_size());
1321 json_writer_start_array(ms
->vmdesc
, "devices");
1323 trace_savevm_state_setup();
1324 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1325 if (se
->vmsd
&& se
->vmsd
->early_setup
) {
1326 ret
= vmstate_save(f
, se
, ms
->vmdesc
, errp
);
1328 migrate_set_error(ms
, *errp
);
1329 qemu_file_set_error(f
, ret
);
1335 if (!se
->ops
|| !se
->ops
->save_setup
) {
1338 if (se
->ops
->is_active
) {
1339 if (!se
->ops
->is_active(se
->opaque
)) {
1343 save_section_header(f
, se
, QEMU_VM_SECTION_START
);
1345 ret
= se
->ops
->save_setup(f
, se
->opaque
, errp
);
1346 save_section_footer(f
, se
);
1348 qemu_file_set_error(f
, ret
);
1357 /* TODO: Should we check that errp is set in case of failure ? */
1358 return precopy_notify(PRECOPY_NOTIFY_SETUP
, errp
);
1361 int qemu_savevm_state_resume_prepare(MigrationState
*s
)
1366 trace_savevm_state_resume_prepare();
1368 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1369 if (!se
->ops
|| !se
->ops
->resume_prepare
) {
1372 if (se
->ops
->is_active
) {
1373 if (!se
->ops
->is_active(se
->opaque
)) {
1377 ret
= se
->ops
->resume_prepare(s
, se
->opaque
);
1387 * this function has three return values:
1388 * negative: there was one error, and we have -errno.
1389 * 0 : We haven't finished, caller have to go again
1390 * 1 : We have finished, we can go to complete phase
1392 int qemu_savevm_state_iterate(QEMUFile
*f
, bool postcopy
)
1395 bool all_finished
= true;
1398 trace_savevm_state_iterate();
1399 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1400 if (!se
->ops
|| !se
->ops
->save_live_iterate
) {
1403 if (se
->ops
->is_active
&&
1404 !se
->ops
->is_active(se
->opaque
)) {
1407 if (se
->ops
->is_active_iterate
&&
1408 !se
->ops
->is_active_iterate(se
->opaque
)) {
1412 * In the postcopy phase, any device that doesn't know how to
1413 * do postcopy should have saved it's state in the _complete
1414 * call that's already run, it might get confused if we call
1415 * iterate afterwards.
1418 !(se
->ops
->has_postcopy
&& se
->ops
->has_postcopy(se
->opaque
))) {
1421 if (migration_rate_exceeded(f
)) {
1424 trace_savevm_section_start(se
->idstr
, se
->section_id
);
1426 save_section_header(f
, se
, QEMU_VM_SECTION_PART
);
1428 ret
= se
->ops
->save_live_iterate(f
, se
->opaque
);
1429 trace_savevm_section_end(se
->idstr
, se
->section_id
, ret
);
1430 save_section_footer(f
, se
);
1433 error_report("failed to save SaveStateEntry with id(name): "
1435 se
->section_id
, se
->idstr
, ret
);
1436 qemu_file_set_error(f
, ret
);
1439 all_finished
= false;
1442 return all_finished
;
1445 static bool should_send_vmdesc(void)
1447 MachineState
*machine
= MACHINE(qdev_get_machine());
1448 bool in_postcopy
= migration_in_postcopy();
1449 return !machine
->suppress_vmdesc
&& !in_postcopy
;
1453 * Calls the save_live_complete_postcopy methods
1454 * causing the last few pages to be sent immediately and doing any associated
1456 * Note postcopy also calls qemu_savevm_state_complete_precopy to complete
1457 * all the other devices, but that happens at the point we switch to postcopy.
1459 void qemu_savevm_state_complete_postcopy(QEMUFile
*f
)
1464 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1465 if (!se
->ops
|| !se
->ops
->save_live_complete_postcopy
) {
1468 if (se
->ops
->is_active
) {
1469 if (!se
->ops
->is_active(se
->opaque
)) {
1473 trace_savevm_section_start(se
->idstr
, se
->section_id
);
1475 qemu_put_byte(f
, QEMU_VM_SECTION_END
);
1476 qemu_put_be32(f
, se
->section_id
);
1478 ret
= se
->ops
->save_live_complete_postcopy(f
, se
->opaque
);
1479 trace_savevm_section_end(se
->idstr
, se
->section_id
, ret
);
1480 save_section_footer(f
, se
);
1482 qemu_file_set_error(f
, ret
);
1487 qemu_put_byte(f
, QEMU_VM_EOF
);
1492 int qemu_savevm_state_complete_precopy_iterable(QEMUFile
*f
, bool in_postcopy
)
1494 int64_t start_ts_each
, end_ts_each
;
1498 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1500 (in_postcopy
&& se
->ops
->has_postcopy
&&
1501 se
->ops
->has_postcopy(se
->opaque
)) ||
1502 !se
->ops
->save_live_complete_precopy
) {
1506 if (se
->ops
->is_active
) {
1507 if (!se
->ops
->is_active(se
->opaque
)) {
1512 start_ts_each
= qemu_clock_get_us(QEMU_CLOCK_REALTIME
);
1513 trace_savevm_section_start(se
->idstr
, se
->section_id
);
1515 save_section_header(f
, se
, QEMU_VM_SECTION_END
);
1517 ret
= se
->ops
->save_live_complete_precopy(f
, se
->opaque
);
1518 trace_savevm_section_end(se
->idstr
, se
->section_id
, ret
);
1519 save_section_footer(f
, se
);
1521 qemu_file_set_error(f
, ret
);
1524 end_ts_each
= qemu_clock_get_us(QEMU_CLOCK_REALTIME
);
1525 trace_vmstate_downtime_save("iterable", se
->idstr
, se
->instance_id
,
1526 end_ts_each
- start_ts_each
);
1529 trace_vmstate_downtime_checkpoint("src-iterable-saved");
1534 int qemu_savevm_state_complete_precopy_non_iterable(QEMUFile
*f
,
1536 bool inactivate_disks
)
1538 MigrationState
*ms
= migrate_get_current();
1539 int64_t start_ts_each
, end_ts_each
;
1540 JSONWriter
*vmdesc
= ms
->vmdesc
;
1543 Error
*local_err
= NULL
;
1546 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1547 if (se
->vmsd
&& se
->vmsd
->early_setup
) {
1548 /* Already saved during qemu_savevm_state_setup(). */
1552 start_ts_each
= qemu_clock_get_us(QEMU_CLOCK_REALTIME
);
1554 ret
= vmstate_save(f
, se
, vmdesc
, &local_err
);
1556 migrate_set_error(ms
, local_err
);
1557 error_report_err(local_err
);
1558 qemu_file_set_error(f
, ret
);
1562 end_ts_each
= qemu_clock_get_us(QEMU_CLOCK_REALTIME
);
1563 trace_vmstate_downtime_save("non-iterable", se
->idstr
, se
->instance_id
,
1564 end_ts_each
- start_ts_each
);
1567 if (inactivate_disks
) {
1568 /* Inactivate before sending QEMU_VM_EOF so that the
1569 * bdrv_activate_all() on the other end won't fail. */
1570 ret
= bdrv_inactivate_all();
1572 error_setg(&local_err
, "%s: bdrv_inactivate_all() failed (%d)",
1574 migrate_set_error(ms
, local_err
);
1575 error_report_err(local_err
);
1576 qemu_file_set_error(f
, ret
);
1581 /* Postcopy stream will still be going */
1582 qemu_put_byte(f
, QEMU_VM_EOF
);
1585 json_writer_end_array(vmdesc
);
1586 json_writer_end_object(vmdesc
);
1587 vmdesc_len
= strlen(json_writer_get(vmdesc
));
1589 if (should_send_vmdesc()) {
1590 qemu_put_byte(f
, QEMU_VM_VMDESCRIPTION
);
1591 qemu_put_be32(f
, vmdesc_len
);
1592 qemu_put_buffer(f
, (uint8_t *)json_writer_get(vmdesc
), vmdesc_len
);
1595 /* Free it now to detect any inconsistencies. */
1596 json_writer_free(vmdesc
);
1599 trace_vmstate_downtime_checkpoint("src-non-iterable-saved");
1604 int qemu_savevm_state_complete_precopy(QEMUFile
*f
, bool iterable_only
,
1605 bool inactivate_disks
)
1608 Error
*local_err
= NULL
;
1609 bool in_postcopy
= migration_in_postcopy();
1611 if (precopy_notify(PRECOPY_NOTIFY_COMPLETE
, &local_err
)) {
1612 error_report_err(local_err
);
1615 trace_savevm_state_complete_precopy();
1617 cpu_synchronize_all_states();
1619 if (!in_postcopy
|| iterable_only
) {
1620 ret
= qemu_savevm_state_complete_precopy_iterable(f
, in_postcopy
);
1626 if (iterable_only
) {
1630 ret
= qemu_savevm_state_complete_precopy_non_iterable(f
, in_postcopy
,
1637 return qemu_fflush(f
);
1640 /* Give an estimate of the amount left to be transferred,
1641 * the result is split into the amount for units that can and
1642 * for units that can't do postcopy.
1644 void qemu_savevm_state_pending_estimate(uint64_t *must_precopy
,
1645 uint64_t *can_postcopy
)
1652 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1653 if (!se
->ops
|| !se
->ops
->state_pending_estimate
) {
1656 if (se
->ops
->is_active
) {
1657 if (!se
->ops
->is_active(se
->opaque
)) {
1661 se
->ops
->state_pending_estimate(se
->opaque
, must_precopy
, can_postcopy
);
1665 void qemu_savevm_state_pending_exact(uint64_t *must_precopy
,
1666 uint64_t *can_postcopy
)
1673 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1674 if (!se
->ops
|| !se
->ops
->state_pending_exact
) {
1677 if (se
->ops
->is_active
) {
1678 if (!se
->ops
->is_active(se
->opaque
)) {
1682 se
->ops
->state_pending_exact(se
->opaque
, must_precopy
, can_postcopy
);
1686 void qemu_savevm_state_cleanup(void)
1689 Error
*local_err
= NULL
;
1691 if (precopy_notify(PRECOPY_NOTIFY_CLEANUP
, &local_err
)) {
1692 error_report_err(local_err
);
1695 trace_savevm_state_cleanup();
1696 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1697 if (se
->ops
&& se
->ops
->save_cleanup
) {
1698 se
->ops
->save_cleanup(se
->opaque
);
1703 static int qemu_savevm_state(QEMUFile
*f
, Error
**errp
)
1706 MigrationState
*ms
= migrate_get_current();
1707 MigrationStatus status
;
1709 if (migration_is_running()) {
1710 error_setg(errp
, QERR_MIGRATION_ACTIVE
);
1714 if (migrate_block()) {
1715 error_setg(errp
, "Block migration and snapshots are incompatible");
1719 ret
= migrate_init(ms
, errp
);
1723 ms
->to_dst_file
= f
;
1725 qemu_savevm_state_header(f
);
1726 ret
= qemu_savevm_state_setup(f
, errp
);
1731 while (qemu_file_get_error(f
) == 0) {
1732 if (qemu_savevm_state_iterate(f
, false) > 0) {
1737 ret
= qemu_file_get_error(f
);
1739 qemu_savevm_state_complete_precopy(f
, false, false);
1740 ret
= qemu_file_get_error(f
);
1743 error_setg_errno(errp
, -ret
, "Error while writing VM state");
1746 qemu_savevm_state_cleanup();
1749 status
= MIGRATION_STATUS_FAILED
;
1751 status
= MIGRATION_STATUS_COMPLETED
;
1753 migrate_set_state(&ms
->state
, MIGRATION_STATUS_SETUP
, status
);
1755 /* f is outer parameter, it should not stay in global migration state after
1756 * this function finished */
1757 ms
->to_dst_file
= NULL
;
1762 void qemu_savevm_live_state(QEMUFile
*f
)
1764 /* save QEMU_VM_SECTION_END section */
1765 qemu_savevm_state_complete_precopy(f
, true, false);
1766 qemu_put_byte(f
, QEMU_VM_EOF
);
1769 int qemu_save_device_state(QEMUFile
*f
)
1771 MigrationState
*ms
= migrate_get_current();
1772 Error
*local_err
= NULL
;
1775 if (!migration_in_colo_state()) {
1776 qemu_put_be32(f
, QEMU_VM_FILE_MAGIC
);
1777 qemu_put_be32(f
, QEMU_VM_FILE_VERSION
);
1779 cpu_synchronize_all_states();
1781 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1787 ret
= vmstate_save(f
, se
, NULL
, &local_err
);
1789 migrate_set_error(ms
, local_err
);
1790 error_report_err(local_err
);
1795 qemu_put_byte(f
, QEMU_VM_EOF
);
1797 return qemu_file_get_error(f
);
1800 static SaveStateEntry
*find_se(const char *idstr
, uint32_t instance_id
)
1804 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
1805 if (!strcmp(se
->idstr
, idstr
) &&
1806 (instance_id
== se
->instance_id
||
1807 instance_id
== se
->alias_id
))
1809 /* Migrating from an older version? */
1810 if (strstr(se
->idstr
, idstr
) && se
->compat
) {
1811 if (!strcmp(se
->compat
->idstr
, idstr
) &&
1812 (instance_id
== se
->compat
->instance_id
||
1813 instance_id
== se
->alias_id
))
1820 enum LoadVMExitCodes
{
1821 /* Allow a command to quit all layers of nested loadvm loops */
1825 /* ------ incoming postcopy messages ------ */
1826 /* 'advise' arrives before any transfers just to tell us that a postcopy
1827 * *might* happen - it might be skipped if precopy transferred everything
1830 static int loadvm_postcopy_handle_advise(MigrationIncomingState
*mis
,
1833 PostcopyState ps
= postcopy_state_set(POSTCOPY_INCOMING_ADVISE
);
1834 uint64_t remote_pagesize_summary
, local_pagesize_summary
, remote_tps
;
1835 size_t page_size
= qemu_target_page_size();
1836 Error
*local_err
= NULL
;
1838 trace_loadvm_postcopy_handle_advise();
1839 if (ps
!= POSTCOPY_INCOMING_NONE
) {
1840 error_report("CMD_POSTCOPY_ADVISE in wrong postcopy state (%d)", ps
);
1846 if (migrate_postcopy_ram()) {
1847 error_report("RAM postcopy is enabled but have 0 byte advise");
1852 if (!migrate_postcopy_ram()) {
1853 error_report("RAM postcopy is disabled but have 16 byte advise");
1858 error_report("CMD_POSTCOPY_ADVISE invalid length (%d)", len
);
1862 if (!postcopy_ram_supported_by_host(mis
, &local_err
)) {
1863 error_report_err(local_err
);
1864 postcopy_state_set(POSTCOPY_INCOMING_NONE
);
1868 remote_pagesize_summary
= qemu_get_be64(mis
->from_src_file
);
1869 local_pagesize_summary
= ram_pagesize_summary();
1871 if (remote_pagesize_summary
!= local_pagesize_summary
) {
1873 * This detects two potential causes of mismatch:
1874 * a) A mismatch in host page sizes
1875 * Some combinations of mismatch are probably possible but it gets
1876 * a bit more complicated. In particular we need to place whole
1877 * host pages on the dest at once, and we need to ensure that we
1878 * handle dirtying to make sure we never end up sending part of
1879 * a hostpage on it's own.
1880 * b) The use of different huge page sizes on source/destination
1881 * a more fine grain test is performed during RAM block migration
1882 * but this test here causes a nice early clear failure, and
1883 * also fails when passed to an older qemu that doesn't
1886 error_report("Postcopy needs matching RAM page sizes (s=%" PRIx64
1888 remote_pagesize_summary
, local_pagesize_summary
);
1892 remote_tps
= qemu_get_be64(mis
->from_src_file
);
1893 if (remote_tps
!= page_size
) {
1895 * Again, some differences could be dealt with, but for now keep it
1898 error_report("Postcopy needs matching target page sizes (s=%d d=%zd)",
1899 (int)remote_tps
, page_size
);
1903 if (postcopy_notify(POSTCOPY_NOTIFY_INBOUND_ADVISE
, &local_err
)) {
1904 error_report_err(local_err
);
1908 if (ram_postcopy_incoming_init(mis
)) {
1915 /* After postcopy we will be told to throw some pages away since they're
1916 * dirty and will have to be demand fetched. Must happen before CPU is
1918 * There can be 0..many of these messages, each encoding multiple pages.
1920 static int loadvm_postcopy_ram_handle_discard(MigrationIncomingState
*mis
,
1925 PostcopyState ps
= postcopy_state_get();
1927 trace_loadvm_postcopy_ram_handle_discard();
1930 case POSTCOPY_INCOMING_ADVISE
:
1932 tmp
= postcopy_ram_prepare_discard(mis
);
1938 case POSTCOPY_INCOMING_DISCARD
:
1939 /* Expected state */
1943 error_report("CMD_POSTCOPY_RAM_DISCARD in wrong postcopy state (%d)",
1947 /* We're expecting a
1949 * a RAM ID string (length byte, name, 0 term)
1950 * then at least 1 16 byte chunk
1952 if (len
< (1 + 1 + 1 + 1 + 2 * 8)) {
1953 error_report("CMD_POSTCOPY_RAM_DISCARD invalid length (%d)", len
);
1957 tmp
= qemu_get_byte(mis
->from_src_file
);
1958 if (tmp
!= postcopy_ram_discard_version
) {
1959 error_report("CMD_POSTCOPY_RAM_DISCARD invalid version (%d)", tmp
);
1963 if (!qemu_get_counted_string(mis
->from_src_file
, ramid
)) {
1964 error_report("CMD_POSTCOPY_RAM_DISCARD Failed to read RAMBlock ID");
1967 tmp
= qemu_get_byte(mis
->from_src_file
);
1969 error_report("CMD_POSTCOPY_RAM_DISCARD missing nil (%d)", tmp
);
1973 len
-= 3 + strlen(ramid
);
1975 error_report("CMD_POSTCOPY_RAM_DISCARD invalid length (%d)", len
);
1978 trace_loadvm_postcopy_ram_handle_discard_header(ramid
, len
);
1980 uint64_t start_addr
, block_length
;
1981 start_addr
= qemu_get_be64(mis
->from_src_file
);
1982 block_length
= qemu_get_be64(mis
->from_src_file
);
1985 int ret
= ram_discard_range(ramid
, start_addr
, block_length
);
1990 trace_loadvm_postcopy_ram_handle_discard_end();
1996 * Triggered by a postcopy_listen command; this thread takes over reading
1997 * the input stream, leaving the main thread free to carry on loading the rest
1998 * of the device state (from RAM).
1999 * (TODO:This could do with being in a postcopy file - but there again it's
2000 * just another input loop, not that postcopy specific)
2002 static void *postcopy_ram_listen_thread(void *opaque
)
2004 MigrationIncomingState
*mis
= migration_incoming_get_current();
2005 QEMUFile
*f
= mis
->from_src_file
;
2007 MigrationState
*migr
= migrate_get_current();
2009 object_ref(OBJECT(migr
));
2011 migrate_set_state(&mis
->state
, MIGRATION_STATUS_ACTIVE
,
2012 MIGRATION_STATUS_POSTCOPY_ACTIVE
);
2013 qemu_sem_post(&mis
->thread_sync_sem
);
2014 trace_postcopy_ram_listen_thread_start();
2016 rcu_register_thread();
2018 * Because we're a thread and not a coroutine we can't yield
2019 * in qemu_file, and thus we must be blocking now.
2021 qemu_file_set_blocking(f
, true);
2022 load_res
= qemu_loadvm_state_main(f
, mis
);
2025 * This is tricky, but, mis->from_src_file can change after it
2026 * returns, when postcopy recovery happened. In the future, we may
2027 * want a wrapper for the QEMUFile handle.
2029 f
= mis
->from_src_file
;
2031 /* And non-blocking again so we don't block in any cleanup */
2032 qemu_file_set_blocking(f
, false);
2034 trace_postcopy_ram_listen_thread_exit();
2036 qemu_file_set_error(f
, load_res
);
2037 dirty_bitmap_mig_cancel_incoming();
2038 if (postcopy_state_get() == POSTCOPY_INCOMING_RUNNING
&&
2039 !migrate_postcopy_ram() && migrate_dirty_bitmaps())
2041 error_report("%s: loadvm failed during postcopy: %d. All states "
2042 "are migrated except dirty bitmaps. Some dirty "
2043 "bitmaps may be lost, and present migrated dirty "
2044 "bitmaps are correctly migrated and valid.",
2045 __func__
, load_res
);
2046 load_res
= 0; /* prevent further exit() */
2048 error_report("%s: loadvm failed: %d", __func__
, load_res
);
2049 migrate_set_state(&mis
->state
, MIGRATION_STATUS_POSTCOPY_ACTIVE
,
2050 MIGRATION_STATUS_FAILED
);
2053 if (load_res
>= 0) {
2055 * This looks good, but it's possible that the device loading in the
2056 * main thread hasn't finished yet, and so we might not be in 'RUN'
2057 * state yet; wait for the end of the main thread.
2059 qemu_event_wait(&mis
->main_thread_load_event
);
2061 postcopy_ram_incoming_cleanup(mis
);
2065 * If something went wrong then we have a bad state so exit;
2066 * depending how far we got it might be possible at this point
2067 * to leave the guest running and fire MCEs for pages that never
2068 * arrived as a desperate recovery step.
2070 rcu_unregister_thread();
2074 migrate_set_state(&mis
->state
, MIGRATION_STATUS_POSTCOPY_ACTIVE
,
2075 MIGRATION_STATUS_COMPLETED
);
2077 * If everything has worked fine, then the main thread has waited
2078 * for us to start, and we're the last use of the mis.
2079 * (If something broke then qemu will have to exit anyway since it's
2080 * got a bad migration state).
2082 migration_incoming_state_destroy();
2083 qemu_loadvm_state_cleanup();
2085 rcu_unregister_thread();
2086 mis
->have_listen_thread
= false;
2087 postcopy_state_set(POSTCOPY_INCOMING_END
);
2089 object_unref(OBJECT(migr
));
2094 /* After this message we must be able to immediately receive postcopy data */
2095 static int loadvm_postcopy_handle_listen(MigrationIncomingState
*mis
)
2097 PostcopyState ps
= postcopy_state_set(POSTCOPY_INCOMING_LISTENING
);
2098 Error
*local_err
= NULL
;
2100 trace_loadvm_postcopy_handle_listen("enter");
2102 if (ps
!= POSTCOPY_INCOMING_ADVISE
&& ps
!= POSTCOPY_INCOMING_DISCARD
) {
2103 error_report("CMD_POSTCOPY_LISTEN in wrong postcopy state (%d)", ps
);
2106 if (ps
== POSTCOPY_INCOMING_ADVISE
) {
2108 * A rare case, we entered listen without having to do any discards,
2109 * so do the setup that's normally done at the time of the 1st discard.
2111 if (migrate_postcopy_ram()) {
2112 postcopy_ram_prepare_discard(mis
);
2116 trace_loadvm_postcopy_handle_listen("after discard");
2119 * Sensitise RAM - can now generate requests for blocks that don't exist
2120 * However, at this point the CPU shouldn't be running, and the IO
2121 * shouldn't be doing anything yet so don't actually expect requests
2123 if (migrate_postcopy_ram()) {
2124 if (postcopy_ram_incoming_setup(mis
)) {
2125 postcopy_ram_incoming_cleanup(mis
);
2130 trace_loadvm_postcopy_handle_listen("after uffd");
2132 if (postcopy_notify(POSTCOPY_NOTIFY_INBOUND_LISTEN
, &local_err
)) {
2133 error_report_err(local_err
);
2137 mis
->have_listen_thread
= true;
2138 postcopy_thread_create(mis
, &mis
->listen_thread
, "postcopy/listen",
2139 postcopy_ram_listen_thread
, QEMU_THREAD_DETACHED
);
2140 trace_loadvm_postcopy_handle_listen("return");
2145 static void loadvm_postcopy_handle_run_bh(void *opaque
)
2147 Error
*local_err
= NULL
;
2148 MigrationIncomingState
*mis
= opaque
;
2150 trace_vmstate_downtime_checkpoint("dst-postcopy-bh-enter");
2152 /* TODO we should move all of this lot into postcopy_ram.c or a shared code
2155 cpu_synchronize_all_post_init();
2157 trace_vmstate_downtime_checkpoint("dst-postcopy-bh-cpu-synced");
2159 qemu_announce_self(&mis
->announce_timer
, migrate_announce_params());
2161 trace_vmstate_downtime_checkpoint("dst-postcopy-bh-announced");
2163 /* Make sure all file formats throw away their mutable metadata.
2164 * If we get an error here, just don't restart the VM yet. */
2165 bdrv_activate_all(&local_err
);
2167 error_report_err(local_err
);
2172 trace_vmstate_downtime_checkpoint("dst-postcopy-bh-cache-invalidated");
2174 dirty_bitmap_mig_before_vm_start();
2177 /* Hold onto your hats, starting the CPU */
2180 /* leave it paused and let management decide when to start the CPU */
2181 runstate_set(RUN_STATE_PAUSED
);
2184 trace_vmstate_downtime_checkpoint("dst-postcopy-bh-vm-started");
2187 /* After all discards we can start running and asking for pages */
2188 static int loadvm_postcopy_handle_run(MigrationIncomingState
*mis
)
2190 PostcopyState ps
= postcopy_state_get();
2192 trace_loadvm_postcopy_handle_run();
2193 if (ps
!= POSTCOPY_INCOMING_LISTENING
) {
2194 error_report("CMD_POSTCOPY_RUN in wrong postcopy state (%d)", ps
);
2198 postcopy_state_set(POSTCOPY_INCOMING_RUNNING
);
2199 migration_bh_schedule(loadvm_postcopy_handle_run_bh
, mis
);
2201 /* We need to finish reading the stream from the package
2202 * and also stop reading anything more from the stream that loaded the
2203 * package (since it's now being read by the listener thread).
2204 * LOADVM_QUIT will quit all the layers of nested loadvm loops.
2209 /* We must be with page_request_mutex held */
2210 static gboolean
postcopy_sync_page_req(gpointer key
, gpointer value
,
2213 MigrationIncomingState
*mis
= data
;
2214 void *host_addr
= (void *) key
;
2215 ram_addr_t rb_offset
;
2219 rb
= qemu_ram_block_from_host(host_addr
, true, &rb_offset
);
2222 * This should _never_ happen. However be nice for a migrating VM to
2223 * not crash/assert. Post an error (note: intended to not use *_once
2224 * because we do want to see all the illegal addresses; and this can
2225 * never be triggered by the guest so we're safe) and move on next.
2227 error_report("%s: illegal host addr %p", __func__
, host_addr
);
2228 /* Try the next entry */
2232 ret
= migrate_send_rp_message_req_pages(mis
, rb
, rb_offset
);
2234 /* Please refer to above comment. */
2235 error_report("%s: send rp message failed for addr %p",
2236 __func__
, host_addr
);
2240 trace_postcopy_page_req_sync(host_addr
);
2245 static void migrate_send_rp_req_pages_pending(MigrationIncomingState
*mis
)
2247 WITH_QEMU_LOCK_GUARD(&mis
->page_request_mutex
) {
2248 g_tree_foreach(mis
->page_requested
, postcopy_sync_page_req
, mis
);
2252 static int loadvm_postcopy_handle_resume(MigrationIncomingState
*mis
)
2254 if (mis
->state
!= MIGRATION_STATUS_POSTCOPY_RECOVER
) {
2255 error_report("%s: illegal resume received", __func__
);
2256 /* Don't fail the load, only for this. */
2261 * Reset the last_rb before we resend any page req to source again, since
2262 * the source should have it reset already.
2264 mis
->last_rb
= NULL
;
2267 * This means source VM is ready to resume the postcopy migration.
2269 migrate_set_state(&mis
->state
, MIGRATION_STATUS_POSTCOPY_RECOVER
,
2270 MIGRATION_STATUS_POSTCOPY_ACTIVE
);
2272 trace_loadvm_postcopy_handle_resume();
2274 /* Tell source that "we are ready" */
2275 migrate_send_rp_resume_ack(mis
, MIGRATION_RESUME_ACK_VALUE
);
2278 * After a postcopy recovery, the source should have lost the postcopy
2279 * queue, or potentially the requested pages could have been lost during
2280 * the network down phase. Let's re-sync with the source VM by re-sending
2281 * all the pending pages that we eagerly need, so these threads won't get
2282 * blocked too long due to the recovery.
2284 * Without this procedure, the faulted destination VM threads (waiting for
2285 * page requests right before the postcopy is interrupted) can keep hanging
2286 * until the pages are sent by the source during the background copying of
2287 * pages, or another thread faulted on the same address accidentally.
2289 migrate_send_rp_req_pages_pending(mis
);
2292 * It's time to switch state and release the fault thread to continue
2293 * service page faults. Note that this should be explicitly after the
2294 * above call to migrate_send_rp_req_pages_pending(). In short:
2295 * migrate_send_rp_message_req_pages() is not thread safe, yet.
2297 qemu_sem_post(&mis
->postcopy_pause_sem_fault
);
2299 if (migrate_postcopy_preempt()) {
2301 * The preempt channel will be created in async manner, now let's
2302 * wait for it and make sure it's created.
2304 qemu_sem_wait(&mis
->postcopy_qemufile_dst_done
);
2305 assert(mis
->postcopy_qemufile_dst
);
2306 /* Kick the fast ram load thread too */
2307 qemu_sem_post(&mis
->postcopy_pause_sem_fast_load
);
2314 * Immediately following this command is a blob of data containing an embedded
2315 * chunk of migration stream; read it and load it.
2317 * @mis: Incoming state
2318 * @length: Length of packaged data to read
2320 * Returns: Negative values on error
2323 static int loadvm_handle_cmd_packaged(MigrationIncomingState
*mis
)
2327 QIOChannelBuffer
*bioc
;
2329 length
= qemu_get_be32(mis
->from_src_file
);
2330 trace_loadvm_handle_cmd_packaged(length
);
2332 if (length
> MAX_VM_CMD_PACKAGED_SIZE
) {
2333 error_report("Unreasonably large packaged state: %zu", length
);
2337 bioc
= qio_channel_buffer_new(length
);
2338 qio_channel_set_name(QIO_CHANNEL(bioc
), "migration-loadvm-buffer");
2339 ret
= qemu_get_buffer(mis
->from_src_file
,
2342 if (ret
!= length
) {
2343 object_unref(OBJECT(bioc
));
2344 error_report("CMD_PACKAGED: Buffer receive fail ret=%d length=%zu",
2346 return (ret
< 0) ? ret
: -EAGAIN
;
2348 bioc
->usage
+= length
;
2349 trace_loadvm_handle_cmd_packaged_received(ret
);
2351 QEMUFile
*packf
= qemu_file_new_input(QIO_CHANNEL(bioc
));
2354 * Before loading the guest states, ensure that the preempt channel has
2355 * been ready to use, as some of the states (e.g. via virtio_load) might
2356 * trigger page faults that will be handled through the preempt channel.
2357 * So yield to the main thread in the case that the channel create event
2358 * hasn't been dispatched.
2360 * TODO: if we can move migration loadvm out of main thread, then we
2361 * won't block main thread from polling the accept() fds. We can drop
2362 * this as a whole when that is done.
2365 if (!migrate_postcopy_preempt() || !qemu_in_coroutine() ||
2366 mis
->postcopy_qemufile_dst
) {
2370 aio_co_schedule(qemu_get_current_aio_context(), qemu_coroutine_self());
2371 qemu_coroutine_yield();
2374 ret
= qemu_loadvm_state_main(packf
, mis
);
2375 trace_loadvm_handle_cmd_packaged_main(ret
);
2377 object_unref(OBJECT(bioc
));
2383 * Handle request that source requests for recved_bitmap on
2384 * destination. Payload format:
2386 * len (1 byte) + ramblock_name (<255 bytes)
2388 static int loadvm_handle_recv_bitmap(MigrationIncomingState
*mis
,
2391 QEMUFile
*file
= mis
->from_src_file
;
2393 char block_name
[256];
2396 cnt
= qemu_get_counted_string(file
, block_name
);
2398 error_report("%s: failed to read block name", __func__
);
2402 /* Validate before using the data */
2403 if (qemu_file_get_error(file
)) {
2404 return qemu_file_get_error(file
);
2407 if (len
!= cnt
+ 1) {
2408 error_report("%s: invalid payload length (%d)", __func__
, len
);
2412 rb
= qemu_ram_block_by_name(block_name
);
2414 error_report("%s: block '%s' not found", __func__
, block_name
);
2418 migrate_send_rp_recv_bitmap(mis
, block_name
);
2420 trace_loadvm_handle_recv_bitmap(block_name
);
2425 static int loadvm_process_enable_colo(MigrationIncomingState
*mis
)
2427 int ret
= migration_incoming_enable_colo();
2430 ret
= colo_init_ram_cache();
2432 migration_incoming_disable_colo();
2439 * Process an incoming 'QEMU_VM_COMMAND'
2440 * 0 just a normal return
2441 * LOADVM_QUIT All good, but exit the loop
2444 static int loadvm_process_command(QEMUFile
*f
)
2446 MigrationIncomingState
*mis
= migration_incoming_get_current();
2451 cmd
= qemu_get_be16(f
);
2452 len
= qemu_get_be16(f
);
2454 /* Check validity before continue processing of cmds */
2455 if (qemu_file_get_error(f
)) {
2456 return qemu_file_get_error(f
);
2459 if (cmd
>= MIG_CMD_MAX
|| cmd
== MIG_CMD_INVALID
) {
2460 error_report("MIG_CMD 0x%x unknown (len 0x%x)", cmd
, len
);
2464 trace_loadvm_process_command(mig_cmd_args
[cmd
].name
, len
);
2466 if (mig_cmd_args
[cmd
].len
!= -1 && mig_cmd_args
[cmd
].len
!= len
) {
2467 error_report("%s received with bad length - expecting %zu, got %d",
2468 mig_cmd_args
[cmd
].name
,
2469 (size_t)mig_cmd_args
[cmd
].len
, len
);
2474 case MIG_CMD_OPEN_RETURN_PATH
:
2475 if (mis
->to_src_file
) {
2476 error_report("CMD_OPEN_RETURN_PATH called when RP already open");
2477 /* Not really a problem, so don't give up */
2480 mis
->to_src_file
= qemu_file_get_return_path(f
);
2481 if (!mis
->to_src_file
) {
2482 error_report("CMD_OPEN_RETURN_PATH failed");
2487 * Switchover ack is enabled but no device uses it, so send an ACK to
2488 * source that it's OK to switchover. Do it here, after return path has
2491 if (migrate_switchover_ack() && !mis
->switchover_ack_pending_num
) {
2492 int ret
= migrate_send_rp_switchover_ack(mis
);
2495 "Could not send switchover ack RP MSG, err %d (%s)", ret
,
2503 tmp32
= qemu_get_be32(f
);
2504 trace_loadvm_process_command_ping(tmp32
);
2505 if (!mis
->to_src_file
) {
2506 error_report("CMD_PING (0x%x) received with no return path",
2510 migrate_send_rp_pong(mis
, tmp32
);
2513 case MIG_CMD_PACKAGED
:
2514 return loadvm_handle_cmd_packaged(mis
);
2516 case MIG_CMD_POSTCOPY_ADVISE
:
2517 return loadvm_postcopy_handle_advise(mis
, len
);
2519 case MIG_CMD_POSTCOPY_LISTEN
:
2520 return loadvm_postcopy_handle_listen(mis
);
2522 case MIG_CMD_POSTCOPY_RUN
:
2523 return loadvm_postcopy_handle_run(mis
);
2525 case MIG_CMD_POSTCOPY_RAM_DISCARD
:
2526 return loadvm_postcopy_ram_handle_discard(mis
, len
);
2528 case MIG_CMD_POSTCOPY_RESUME
:
2529 return loadvm_postcopy_handle_resume(mis
);
2531 case MIG_CMD_RECV_BITMAP
:
2532 return loadvm_handle_recv_bitmap(mis
, len
);
2534 case MIG_CMD_ENABLE_COLO
:
2535 return loadvm_process_enable_colo(mis
);
2542 * Read a footer off the wire and check that it matches the expected section
2544 * Returns: true if the footer was good
2545 * false if there is a problem (and calls error_report to say why)
2547 static bool check_section_footer(QEMUFile
*f
, SaveStateEntry
*se
)
2551 uint32_t read_section_id
;
2553 if (!migrate_get_current()->send_section_footer
) {
2554 /* No footer to check */
2558 read_mark
= qemu_get_byte(f
);
2560 ret
= qemu_file_get_error(f
);
2562 error_report("%s: Read section footer failed: %d",
2567 if (read_mark
!= QEMU_VM_SECTION_FOOTER
) {
2568 error_report("Missing section footer for %s", se
->idstr
);
2572 read_section_id
= qemu_get_be32(f
);
2573 if (read_section_id
!= se
->load_section_id
) {
2574 error_report("Mismatched section id in footer for %s -"
2575 " read 0x%x expected 0x%x",
2576 se
->idstr
, read_section_id
, se
->load_section_id
);
2585 qemu_loadvm_section_start_full(QEMUFile
*f
, MigrationIncomingState
*mis
,
2588 bool trace_downtime
= (type
== QEMU_VM_SECTION_FULL
);
2589 uint32_t instance_id
, version_id
, section_id
;
2590 int64_t start_ts
, end_ts
;
2595 /* Read section start */
2596 section_id
= qemu_get_be32(f
);
2597 if (!qemu_get_counted_string(f
, idstr
)) {
2598 error_report("Unable to read ID string for section %u",
2602 instance_id
= qemu_get_be32(f
);
2603 version_id
= qemu_get_be32(f
);
2605 ret
= qemu_file_get_error(f
);
2607 error_report("%s: Failed to read instance/version ID: %d",
2612 trace_qemu_loadvm_state_section_startfull(section_id
, idstr
,
2613 instance_id
, version_id
);
2614 /* Find savevm section */
2615 se
= find_se(idstr
, instance_id
);
2617 error_report("Unknown savevm section or instance '%s' %"PRIu32
". "
2618 "Make sure that your current VM setup matches your "
2619 "saved VM setup, including any hotplugged devices",
2620 idstr
, instance_id
);
2624 /* Validate version */
2625 if (version_id
> se
->version_id
) {
2626 error_report("savevm: unsupported version %d for '%s' v%d",
2627 version_id
, idstr
, se
->version_id
);
2630 se
->load_version_id
= version_id
;
2631 se
->load_section_id
= section_id
;
2633 /* Validate if it is a device's state */
2634 if (xen_enabled() && se
->is_ram
) {
2635 error_report("loadvm: %s RAM loading not allowed on Xen", idstr
);
2639 if (trace_downtime
) {
2640 start_ts
= qemu_clock_get_us(QEMU_CLOCK_REALTIME
);
2643 ret
= vmstate_load(f
, se
);
2645 error_report("error while loading state for instance 0x%"PRIx32
" of"
2646 " device '%s'", instance_id
, idstr
);
2650 if (trace_downtime
) {
2651 end_ts
= qemu_clock_get_us(QEMU_CLOCK_REALTIME
);
2652 trace_vmstate_downtime_load("non-iterable", se
->idstr
,
2653 se
->instance_id
, end_ts
- start_ts
);
2656 if (!check_section_footer(f
, se
)) {
2664 qemu_loadvm_section_part_end(QEMUFile
*f
, MigrationIncomingState
*mis
,
2667 bool trace_downtime
= (type
== QEMU_VM_SECTION_END
);
2668 int64_t start_ts
, end_ts
;
2669 uint32_t section_id
;
2673 section_id
= qemu_get_be32(f
);
2675 ret
= qemu_file_get_error(f
);
2677 error_report("%s: Failed to read section ID: %d",
2682 trace_qemu_loadvm_state_section_partend(section_id
);
2683 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
2684 if (se
->load_section_id
== section_id
) {
2689 error_report("Unknown savevm section %d", section_id
);
2693 if (trace_downtime
) {
2694 start_ts
= qemu_clock_get_us(QEMU_CLOCK_REALTIME
);
2697 ret
= vmstate_load(f
, se
);
2699 error_report("error while loading state section id %d(%s)",
2700 section_id
, se
->idstr
);
2704 if (trace_downtime
) {
2705 end_ts
= qemu_clock_get_us(QEMU_CLOCK_REALTIME
);
2706 trace_vmstate_downtime_load("iterable", se
->idstr
,
2707 se
->instance_id
, end_ts
- start_ts
);
2710 if (!check_section_footer(f
, se
)) {
2717 static int qemu_loadvm_state_header(QEMUFile
*f
)
2722 v
= qemu_get_be32(f
);
2723 if (v
!= QEMU_VM_FILE_MAGIC
) {
2724 error_report("Not a migration stream");
2728 v
= qemu_get_be32(f
);
2729 if (v
== QEMU_VM_FILE_VERSION_COMPAT
) {
2730 error_report("SaveVM v2 format is obsolete and don't work anymore");
2733 if (v
!= QEMU_VM_FILE_VERSION
) {
2734 error_report("Unsupported migration stream version");
2738 if (migrate_get_current()->send_configuration
) {
2739 if (qemu_get_byte(f
) != QEMU_VM_CONFIGURATION
) {
2740 error_report("Configuration section missing");
2741 qemu_loadvm_state_cleanup();
2744 ret
= vmstate_load_state(f
, &vmstate_configuration
, &savevm_state
, 0);
2747 qemu_loadvm_state_cleanup();
2754 static void qemu_loadvm_state_switchover_ack_needed(MigrationIncomingState
*mis
)
2758 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
2759 if (!se
->ops
|| !se
->ops
->switchover_ack_needed
) {
2763 if (se
->ops
->switchover_ack_needed(se
->opaque
)) {
2764 mis
->switchover_ack_pending_num
++;
2768 trace_loadvm_state_switchover_ack_needed(mis
->switchover_ack_pending_num
);
2771 static int qemu_loadvm_state_setup(QEMUFile
*f
, Error
**errp
)
2777 trace_loadvm_state_setup();
2778 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
2779 if (!se
->ops
|| !se
->ops
->load_setup
) {
2782 if (se
->ops
->is_active
) {
2783 if (!se
->ops
->is_active(se
->opaque
)) {
2788 ret
= se
->ops
->load_setup(f
, se
->opaque
, errp
);
2790 error_prepend(errp
, "Load state of device %s failed: ",
2792 qemu_file_set_error(f
, ret
);
2799 void qemu_loadvm_state_cleanup(void)
2803 trace_loadvm_state_cleanup();
2804 QTAILQ_FOREACH(se
, &savevm_state
.handlers
, entry
) {
2805 if (se
->ops
&& se
->ops
->load_cleanup
) {
2806 se
->ops
->load_cleanup(se
->opaque
);
2811 /* Return true if we should continue the migration, or false. */
2812 static bool postcopy_pause_incoming(MigrationIncomingState
*mis
)
2816 trace_postcopy_pause_incoming();
2818 assert(migrate_postcopy_ram());
2821 * Unregister yank with either from/to src would work, since ioc behind it
2824 migration_ioc_unregister_yank_from_file(mis
->from_src_file
);
2826 assert(mis
->from_src_file
);
2827 qemu_file_shutdown(mis
->from_src_file
);
2828 qemu_fclose(mis
->from_src_file
);
2829 mis
->from_src_file
= NULL
;
2831 assert(mis
->to_src_file
);
2832 qemu_file_shutdown(mis
->to_src_file
);
2833 qemu_mutex_lock(&mis
->rp_mutex
);
2834 qemu_fclose(mis
->to_src_file
);
2835 mis
->to_src_file
= NULL
;
2836 qemu_mutex_unlock(&mis
->rp_mutex
);
2839 * NOTE: this must happen before reset the PostcopyTmpPages below,
2840 * otherwise it's racy to reset those fields when the fast load thread
2841 * can be accessing it in parallel.
2843 if (mis
->postcopy_qemufile_dst
) {
2844 qemu_file_shutdown(mis
->postcopy_qemufile_dst
);
2845 /* Take the mutex to make sure the fast ram load thread halted */
2846 qemu_mutex_lock(&mis
->postcopy_prio_thread_mutex
);
2847 migration_ioc_unregister_yank_from_file(mis
->postcopy_qemufile_dst
);
2848 qemu_fclose(mis
->postcopy_qemufile_dst
);
2849 mis
->postcopy_qemufile_dst
= NULL
;
2850 qemu_mutex_unlock(&mis
->postcopy_prio_thread_mutex
);
2853 /* Current state can be either ACTIVE or RECOVER */
2854 migrate_set_state(&mis
->state
, mis
->state
,
2855 MIGRATION_STATUS_POSTCOPY_PAUSED
);
2857 /* Notify the fault thread for the invalidated file handle */
2858 postcopy_fault_thread_notify(mis
);
2861 * If network is interrupted, any temp page we received will be useless
2862 * because we didn't mark them as "received" in receivedmap. After a
2863 * proper recovery later (which will sync src dirty bitmap with receivedmap
2864 * on dest) these cached small pages will be resent again.
2866 for (i
= 0; i
< mis
->postcopy_channels
; i
++) {
2867 postcopy_temp_page_reset(&mis
->postcopy_tmp_pages
[i
]);
2870 error_report("Detected IO failure for postcopy. "
2871 "Migration paused.");
2873 while (mis
->state
== MIGRATION_STATUS_POSTCOPY_PAUSED
) {
2874 qemu_sem_wait(&mis
->postcopy_pause_sem_dst
);
2877 trace_postcopy_pause_incoming_continued();
2882 int qemu_loadvm_state_main(QEMUFile
*f
, MigrationIncomingState
*mis
)
2884 uint8_t section_type
;
2889 section_type
= qemu_get_byte(f
);
2891 ret
= qemu_file_get_error_obj_any(f
, mis
->postcopy_qemufile_dst
, NULL
);
2896 trace_qemu_loadvm_state_section(section_type
);
2897 switch (section_type
) {
2898 case QEMU_VM_SECTION_START
:
2899 case QEMU_VM_SECTION_FULL
:
2900 ret
= qemu_loadvm_section_start_full(f
, mis
, section_type
);
2905 case QEMU_VM_SECTION_PART
:
2906 case QEMU_VM_SECTION_END
:
2907 ret
= qemu_loadvm_section_part_end(f
, mis
, section_type
);
2912 case QEMU_VM_COMMAND
:
2913 ret
= loadvm_process_command(f
);
2914 trace_qemu_loadvm_state_section_command(ret
);
2915 if ((ret
< 0) || (ret
== LOADVM_QUIT
)) {
2920 /* This is the end of migration */
2923 error_report("Unknown savevm section type %d", section_type
);
2931 qemu_file_set_error(f
, ret
);
2933 /* Cancel bitmaps incoming regardless of recovery */
2934 dirty_bitmap_mig_cancel_incoming();
2937 * If we are during an active postcopy, then we pause instead
2938 * of bail out to at least keep the VM's dirty data. Note
2939 * that POSTCOPY_INCOMING_LISTENING stage is still not enough,
2940 * during which we're still receiving device states and we
2941 * still haven't yet started the VM on destination.
2943 * Only RAM postcopy supports recovery. Still, if RAM postcopy is
2944 * enabled, canceled bitmaps postcopy will not affect RAM postcopy
2947 if (postcopy_state_get() == POSTCOPY_INCOMING_RUNNING
&&
2948 migrate_postcopy_ram() && postcopy_pause_incoming(mis
)) {
2949 /* Reset f to point to the newly created channel */
2950 f
= mis
->from_src_file
;
2957 int qemu_loadvm_state(QEMUFile
*f
)
2959 MigrationIncomingState
*mis
= migration_incoming_get_current();
2960 Error
*local_err
= NULL
;
2963 if (qemu_savevm_state_blocked(&local_err
)) {
2964 error_report_err(local_err
);
2968 ret
= qemu_loadvm_state_header(f
);
2973 if (qemu_loadvm_state_setup(f
, &local_err
) != 0) {
2974 error_report_err(local_err
);
2978 if (migrate_switchover_ack()) {
2979 qemu_loadvm_state_switchover_ack_needed(mis
);
2982 cpu_synchronize_all_pre_loadvm();
2984 ret
= qemu_loadvm_state_main(f
, mis
);
2985 qemu_event_set(&mis
->main_thread_load_event
);
2987 trace_qemu_loadvm_state_post_main(ret
);
2989 if (mis
->have_listen_thread
) {
2990 /* Listen thread still going, can't clean up yet */
2995 ret
= qemu_file_get_error(f
);
2999 * Try to read in the VMDESC section as well, so that dumping tools that
3000 * intercept our migration stream have the chance to see it.
3003 /* We've got to be careful; if we don't read the data and just shut the fd
3004 * then the sender can error if we close while it's still sending.
3005 * We also mustn't read data that isn't there; some transports (RDMA)
3006 * will stall waiting for that data when the source has already closed.
3008 if (ret
== 0 && should_send_vmdesc()) {
3011 uint8_t section_type
= qemu_get_byte(f
);
3013 if (section_type
!= QEMU_VM_VMDESCRIPTION
) {
3014 error_report("Expected vmdescription section, but got %d",
3017 * It doesn't seem worth failing at this point since
3018 * we apparently have an otherwise valid VM state
3021 buf
= g_malloc(0x1000);
3022 size
= qemu_get_be32(f
);
3025 uint32_t read_chunk
= MIN(size
, 0x1000);
3026 qemu_get_buffer(f
, buf
, read_chunk
);
3033 qemu_loadvm_state_cleanup();
3034 cpu_synchronize_all_post_init();
3039 int qemu_load_device_state(QEMUFile
*f
)
3041 MigrationIncomingState
*mis
= migration_incoming_get_current();
3044 /* Load QEMU_VM_SECTION_FULL section */
3045 ret
= qemu_loadvm_state_main(f
, mis
);
3047 error_report("Failed to load device state: %d", ret
);
3051 cpu_synchronize_all_post_init();
3055 int qemu_loadvm_approve_switchover(void)
3057 MigrationIncomingState
*mis
= migration_incoming_get_current();
3059 if (!mis
->switchover_ack_pending_num
) {
3063 mis
->switchover_ack_pending_num
--;
3064 trace_loadvm_approve_switchover(mis
->switchover_ack_pending_num
);
3066 if (mis
->switchover_ack_pending_num
) {
3070 return migrate_send_rp_switchover_ack(mis
);
3073 bool save_snapshot(const char *name
, bool overwrite
, const char *vmstate
,
3074 bool has_devices
, strList
*devices
, Error
**errp
)
3076 BlockDriverState
*bs
;
3077 QEMUSnapshotInfo sn1
, *sn
= &sn1
;
3080 RunState saved_state
= runstate_get();
3081 uint64_t vm_state_size
;
3082 g_autoptr(GDateTime
) now
= g_date_time_new_now_local();
3084 GLOBAL_STATE_CODE();
3086 if (migration_is_blocked(errp
)) {
3090 if (!replay_can_snapshot()) {
3091 error_setg(errp
, "Record/replay does not allow making snapshot "
3092 "right now. Try once more later.");
3096 if (!bdrv_all_can_snapshot(has_devices
, devices
, errp
)) {
3100 /* Delete old snapshots of the same name */
3103 if (bdrv_all_delete_snapshot(name
, has_devices
,
3104 devices
, errp
) < 0) {
3108 ret2
= bdrv_all_has_snapshot(name
, has_devices
, devices
, errp
);
3114 "Snapshot '%s' already exists in one or more devices",
3121 bs
= bdrv_all_find_vmstate_bs(vmstate
, has_devices
, devices
, errp
);
3126 global_state_store();
3127 vm_stop(RUN_STATE_SAVE_VM
);
3129 bdrv_drain_all_begin();
3131 memset(sn
, 0, sizeof(*sn
));
3133 /* fill auxiliary fields */
3134 sn
->date_sec
= g_date_time_to_unix(now
);
3135 sn
->date_nsec
= g_date_time_get_microsecond(now
) * 1000;
3136 sn
->vm_clock_nsec
= qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL
);
3137 if (replay_mode
!= REPLAY_MODE_NONE
) {
3138 sn
->icount
= replay_get_current_icount();
3144 pstrcpy(sn
->name
, sizeof(sn
->name
), name
);
3146 g_autofree
char *autoname
= g_date_time_format(now
, "vm-%Y%m%d%H%M%S");
3147 pstrcpy(sn
->name
, sizeof(sn
->name
), autoname
);
3150 /* save the VM state */
3151 f
= qemu_fopen_bdrv(bs
, 1);
3153 error_setg(errp
, "Could not open VM state file");
3156 ret
= qemu_savevm_state(f
, errp
);
3157 vm_state_size
= qemu_file_transferred(f
);
3158 ret2
= qemu_fclose(f
);
3167 ret
= bdrv_all_create_snapshot(sn
, bs
, vm_state_size
,
3168 has_devices
, devices
, errp
);
3170 bdrv_all_delete_snapshot(sn
->name
, has_devices
, devices
, NULL
);
3177 bdrv_drain_all_end();
3179 vm_resume(saved_state
);
3183 void qmp_xen_save_devices_state(const char *filename
, bool has_live
, bool live
,
3187 QIOChannelFile
*ioc
;
3188 int saved_vm_running
;
3192 /* live default to true so old version of Xen tool stack can have a
3193 * successful live migration */
3197 saved_vm_running
= runstate_is_running();
3198 vm_stop(RUN_STATE_SAVE_VM
);
3199 global_state_store_running();
3201 ioc
= qio_channel_file_new_path(filename
, O_WRONLY
| O_CREAT
| O_TRUNC
,
3206 qio_channel_set_name(QIO_CHANNEL(ioc
), "migration-xen-save-state");
3207 f
= qemu_file_new_output(QIO_CHANNEL(ioc
));
3208 object_unref(OBJECT(ioc
));
3209 ret
= qemu_save_device_state(f
);
3210 if (ret
< 0 || qemu_fclose(f
) < 0) {
3211 error_setg(errp
, QERR_IO_ERROR
);
3213 /* libxl calls the QMP command "stop" before calling
3214 * "xen-save-devices-state" and in case of migration failure, libxl
3215 * would call "cont".
3216 * So call bdrv_inactivate_all (release locks) here to let the other
3217 * side of the migration take control of the images.
3219 if (live
&& !saved_vm_running
) {
3220 ret
= bdrv_inactivate_all();
3222 error_setg(errp
, "%s: bdrv_inactivate_all() failed (%d)",
3229 if (saved_vm_running
) {
3234 void qmp_xen_load_devices_state(const char *filename
, Error
**errp
)
3237 QIOChannelFile
*ioc
;
3240 /* Guest must be paused before loading the device state; the RAM state
3241 * will already have been loaded by xc
3243 if (runstate_is_running()) {
3244 error_setg(errp
, "Cannot update device state while vm is running");
3247 vm_stop(RUN_STATE_RESTORE_VM
);
3249 ioc
= qio_channel_file_new_path(filename
, O_RDONLY
| O_BINARY
, 0, errp
);
3253 qio_channel_set_name(QIO_CHANNEL(ioc
), "migration-xen-load-state");
3254 f
= qemu_file_new_input(QIO_CHANNEL(ioc
));
3255 object_unref(OBJECT(ioc
));
3257 ret
= qemu_loadvm_state(f
);
3260 error_setg(errp
, QERR_IO_ERROR
);
3262 migration_incoming_state_destroy();
3265 bool load_snapshot(const char *name
, const char *vmstate
,
3266 bool has_devices
, strList
*devices
, Error
**errp
)
3268 BlockDriverState
*bs_vm_state
;
3269 QEMUSnapshotInfo sn
;
3272 MigrationIncomingState
*mis
= migration_incoming_get_current();
3274 if (!bdrv_all_can_snapshot(has_devices
, devices
, errp
)) {
3277 ret
= bdrv_all_has_snapshot(name
, has_devices
, devices
, errp
);
3282 error_setg(errp
, "Snapshot '%s' does not exist in one or more devices",
3287 bs_vm_state
= bdrv_all_find_vmstate_bs(vmstate
, has_devices
, devices
, errp
);
3292 /* Don't even try to load empty VM states */
3293 ret
= bdrv_snapshot_find(bs_vm_state
, &sn
, name
);
3296 } else if (sn
.vm_state_size
== 0) {
3297 error_setg(errp
, "This is a disk-only snapshot. Revert to it "
3298 " offline using qemu-img");
3303 * Flush the record/replay queue. Now the VM state is going
3304 * to change. Therefore we don't need to preserve its consistency
3306 replay_flush_events();
3308 /* Flush all IO requests so they don't interfere with the new state. */
3309 bdrv_drain_all_begin();
3311 ret
= bdrv_all_goto_snapshot(name
, has_devices
, devices
, errp
);
3316 /* restore the VM state */
3317 f
= qemu_fopen_bdrv(bs_vm_state
, 0);
3319 error_setg(errp
, "Could not open VM state file");
3323 qemu_system_reset(SHUTDOWN_CAUSE_SNAPSHOT_LOAD
);
3324 mis
->from_src_file
= f
;
3326 if (!yank_register_instance(MIGRATION_YANK_INSTANCE
, errp
)) {
3330 ret
= qemu_loadvm_state(f
);
3331 migration_incoming_state_destroy();
3333 bdrv_drain_all_end();
3336 error_setg(errp
, "Error %d while loading VM state", ret
);
3343 bdrv_drain_all_end();
3347 void load_snapshot_resume(RunState state
)
3350 if (state
== RUN_STATE_RUNNING
&& runstate_get() == RUN_STATE_SUSPENDED
) {
3351 qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER
, &error_abort
);
3355 bool delete_snapshot(const char *name
, bool has_devices
,
3356 strList
*devices
, Error
**errp
)
3358 if (!bdrv_all_can_snapshot(has_devices
, devices
, errp
)) {
3362 if (bdrv_all_delete_snapshot(name
, has_devices
, devices
, errp
) < 0) {
3369 void vmstate_register_ram(MemoryRegion
*mr
, DeviceState
*dev
)
3371 qemu_ram_set_idstr(mr
->ram_block
,
3372 memory_region_name(mr
), dev
);
3373 qemu_ram_set_migratable(mr
->ram_block
);
3376 void vmstate_unregister_ram(MemoryRegion
*mr
, DeviceState
*dev
)
3378 qemu_ram_unset_idstr(mr
->ram_block
);
3379 qemu_ram_unset_migratable(mr
->ram_block
);
3382 void vmstate_register_ram_global(MemoryRegion
*mr
)
3384 vmstate_register_ram(mr
, NULL
);
3387 bool vmstate_check_only_migratable(const VMStateDescription
*vmsd
)
3389 /* check needed if --only-migratable is specified */
3390 if (!only_migratable
) {
3394 return !(vmsd
&& vmsd
->unmigratable
);
3397 typedef struct SnapshotJob
{
3407 static void qmp_snapshot_job_free(SnapshotJob
*s
)
3411 qapi_free_strList(s
->devices
);
3415 static void snapshot_load_job_bh(void *opaque
)
3418 SnapshotJob
*s
= container_of(job
, SnapshotJob
, common
);
3419 RunState orig_state
= runstate_get();
3421 job_progress_set_remaining(&s
->common
, 1);
3423 vm_stop(RUN_STATE_RESTORE_VM
);
3425 s
->ret
= load_snapshot(s
->tag
, s
->vmstate
, true, s
->devices
, s
->errp
);
3427 load_snapshot_resume(orig_state
);
3430 job_progress_update(&s
->common
, 1);
3432 qmp_snapshot_job_free(s
);
3436 static void snapshot_save_job_bh(void *opaque
)
3439 SnapshotJob
*s
= container_of(job
, SnapshotJob
, common
);
3441 job_progress_set_remaining(&s
->common
, 1);
3442 s
->ret
= save_snapshot(s
->tag
, false, s
->vmstate
,
3443 true, s
->devices
, s
->errp
);
3444 job_progress_update(&s
->common
, 1);
3446 qmp_snapshot_job_free(s
);
3450 static void snapshot_delete_job_bh(void *opaque
)
3453 SnapshotJob
*s
= container_of(job
, SnapshotJob
, common
);
3455 job_progress_set_remaining(&s
->common
, 1);
3456 s
->ret
= delete_snapshot(s
->tag
, true, s
->devices
, s
->errp
);
3457 job_progress_update(&s
->common
, 1);
3459 qmp_snapshot_job_free(s
);
3463 static int coroutine_fn
snapshot_save_job_run(Job
*job
, Error
**errp
)
3465 SnapshotJob
*s
= container_of(job
, SnapshotJob
, common
);
3467 s
->co
= qemu_coroutine_self();
3468 aio_bh_schedule_oneshot(qemu_get_aio_context(),
3469 snapshot_save_job_bh
, job
);
3470 qemu_coroutine_yield();
3471 return s
->ret
? 0 : -1;
3474 static int coroutine_fn
snapshot_load_job_run(Job
*job
, Error
**errp
)
3476 SnapshotJob
*s
= container_of(job
, SnapshotJob
, common
);
3478 s
->co
= qemu_coroutine_self();
3479 aio_bh_schedule_oneshot(qemu_get_aio_context(),
3480 snapshot_load_job_bh
, job
);
3481 qemu_coroutine_yield();
3482 return s
->ret
? 0 : -1;
3485 static int coroutine_fn
snapshot_delete_job_run(Job
*job
, Error
**errp
)
3487 SnapshotJob
*s
= container_of(job
, SnapshotJob
, common
);
3489 s
->co
= qemu_coroutine_self();
3490 aio_bh_schedule_oneshot(qemu_get_aio_context(),
3491 snapshot_delete_job_bh
, job
);
3492 qemu_coroutine_yield();
3493 return s
->ret
? 0 : -1;
3497 static const JobDriver snapshot_load_job_driver
= {
3498 .instance_size
= sizeof(SnapshotJob
),
3499 .job_type
= JOB_TYPE_SNAPSHOT_LOAD
,
3500 .run
= snapshot_load_job_run
,
3503 static const JobDriver snapshot_save_job_driver
= {
3504 .instance_size
= sizeof(SnapshotJob
),
3505 .job_type
= JOB_TYPE_SNAPSHOT_SAVE
,
3506 .run
= snapshot_save_job_run
,
3509 static const JobDriver snapshot_delete_job_driver
= {
3510 .instance_size
= sizeof(SnapshotJob
),
3511 .job_type
= JOB_TYPE_SNAPSHOT_DELETE
,
3512 .run
= snapshot_delete_job_run
,
3516 void qmp_snapshot_save(const char *job_id
,
3518 const char *vmstate
,
3524 s
= job_create(job_id
, &snapshot_save_job_driver
, NULL
,
3525 qemu_get_aio_context(), JOB_MANUAL_DISMISS
,
3531 s
->tag
= g_strdup(tag
);
3532 s
->vmstate
= g_strdup(vmstate
);
3533 s
->devices
= QAPI_CLONE(strList
, devices
);
3535 job_start(&s
->common
);
3538 void qmp_snapshot_load(const char *job_id
,
3540 const char *vmstate
,
3546 s
= job_create(job_id
, &snapshot_load_job_driver
, NULL
,
3547 qemu_get_aio_context(), JOB_MANUAL_DISMISS
,
3553 s
->tag
= g_strdup(tag
);
3554 s
->vmstate
= g_strdup(vmstate
);
3555 s
->devices
= QAPI_CLONE(strList
, devices
);
3557 job_start(&s
->common
);
3560 void qmp_snapshot_delete(const char *job_id
,
3567 s
= job_create(job_id
, &snapshot_delete_job_driver
, NULL
,
3568 qemu_get_aio_context(), JOB_MANUAL_DISMISS
,
3574 s
->tag
= g_strdup(tag
);
3575 s
->devices
= QAPI_CLONE(strList
, devices
);
3577 job_start(&s
->common
);