| /* |
| * QEMU System Emulator |
| * |
| * Copyright (c) 2003-2008 Fabrice Bellard |
| * Copyright (c) 2009-2015 Red Hat Inc |
| * |
| * Authors: |
| * Juan Quintela <quintela@redhat.com> |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to deal |
| * in the Software without restriction, including without limitation the rights |
| * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| * copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| * THE SOFTWARE. |
| */ |
| |
| #include "qemu/osdep.h" |
| #include "hw/boards.h" |
| #include "net/net.h" |
| #include "migration.h" |
| #include "migration/snapshot.h" |
| #include "migration-stats.h" |
| #include "migration/vmstate.h" |
| #include "migration/misc.h" |
| #include "migration/register.h" |
| #include "migration/global_state.h" |
| #include "migration/channel-block.h" |
| #include "ram.h" |
| #include "qemu-file.h" |
| #include "savevm.h" |
| #include "postcopy-ram.h" |
| #include "qapi/error.h" |
| #include "qapi/qapi-commands-migration.h" |
| #include "qapi/clone-visitor.h" |
| #include "qapi/qapi-builtin-visit.h" |
| #include "qemu/error-report.h" |
| #include "sysemu/cpus.h" |
| #include "exec/memory.h" |
| #include "exec/target_page.h" |
| #include "trace.h" |
| #include "qemu/iov.h" |
| #include "qemu/job.h" |
| #include "qemu/main-loop.h" |
| #include "block/snapshot.h" |
| #include "qemu/cutils.h" |
| #include "io/channel-buffer.h" |
| #include "io/channel-file.h" |
| #include "sysemu/replay.h" |
| #include "sysemu/runstate.h" |
| #include "sysemu/sysemu.h" |
| #include "sysemu/xen.h" |
| #include "migration/colo.h" |
| #include "qemu/bitmap.h" |
| #include "net/announce.h" |
| #include "qemu/yank.h" |
| #include "yank_functions.h" |
| #include "sysemu/qtest.h" |
| #include "options.h" |
| |
| const unsigned int postcopy_ram_discard_version; |
| |
| /* Subcommands for QEMU_VM_COMMAND */ |
| enum qemu_vm_cmd { |
| MIG_CMD_INVALID = 0, /* Must be 0 */ |
| MIG_CMD_OPEN_RETURN_PATH, /* Tell the dest to open the Return path */ |
| MIG_CMD_PING, /* Request a PONG on the RP */ |
| |
| MIG_CMD_POSTCOPY_ADVISE, /* Prior to any page transfers, just |
| warn we might want to do PC */ |
| MIG_CMD_POSTCOPY_LISTEN, /* Start listening for incoming |
| pages as it's running. */ |
| MIG_CMD_POSTCOPY_RUN, /* Start execution */ |
| |
| MIG_CMD_POSTCOPY_RAM_DISCARD, /* A list of pages to discard that |
| were previously sent during |
| precopy but are dirty. */ |
| MIG_CMD_PACKAGED, /* Send a wrapped stream within this stream */ |
| MIG_CMD_ENABLE_COLO, /* Enable COLO */ |
| MIG_CMD_POSTCOPY_RESUME, /* resume postcopy on dest */ |
| MIG_CMD_RECV_BITMAP, /* Request for recved bitmap on dst */ |
| MIG_CMD_MAX |
| }; |
| |
| #define MAX_VM_CMD_PACKAGED_SIZE UINT32_MAX |
| static struct mig_cmd_args { |
| ssize_t len; /* -1 = variable */ |
| const char *name; |
| } mig_cmd_args[] = { |
| [MIG_CMD_INVALID] = { .len = -1, .name = "INVALID" }, |
| [MIG_CMD_OPEN_RETURN_PATH] = { .len = 0, .name = "OPEN_RETURN_PATH" }, |
| [MIG_CMD_PING] = { .len = sizeof(uint32_t), .name = "PING" }, |
| [MIG_CMD_POSTCOPY_ADVISE] = { .len = -1, .name = "POSTCOPY_ADVISE" }, |
| [MIG_CMD_POSTCOPY_LISTEN] = { .len = 0, .name = "POSTCOPY_LISTEN" }, |
| [MIG_CMD_POSTCOPY_RUN] = { .len = 0, .name = "POSTCOPY_RUN" }, |
| [MIG_CMD_POSTCOPY_RAM_DISCARD] = { |
| .len = -1, .name = "POSTCOPY_RAM_DISCARD" }, |
| [MIG_CMD_POSTCOPY_RESUME] = { .len = 0, .name = "POSTCOPY_RESUME" }, |
| [MIG_CMD_PACKAGED] = { .len = 4, .name = "PACKAGED" }, |
| [MIG_CMD_RECV_BITMAP] = { .len = -1, .name = "RECV_BITMAP" }, |
| [MIG_CMD_MAX] = { .len = -1, .name = "MAX" }, |
| }; |
| |
| /* Note for MIG_CMD_POSTCOPY_ADVISE: |
| * The format of arguments is depending on postcopy mode: |
| * - postcopy RAM only |
| * uint64_t host page size |
| * uint64_t target page size |
| * |
| * - postcopy RAM and postcopy dirty bitmaps |
| * format is the same as for postcopy RAM only |
| * |
| * - postcopy dirty bitmaps only |
| * Nothing. Command length field is 0. |
| * |
| * Be careful: adding a new postcopy entity with some other parameters should |
| * not break format self-description ability. Good way is to introduce some |
| * generic extendable format with an exception for two old entities. |
| */ |
| |
| /***********************************************************/ |
| /* savevm/loadvm support */ |
| |
| static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int is_writable) |
| { |
| if (is_writable) { |
| return qemu_file_new_output(QIO_CHANNEL(qio_channel_block_new(bs))); |
| } else { |
| return qemu_file_new_input(QIO_CHANNEL(qio_channel_block_new(bs))); |
| } |
| } |
| |
| |
| /* QEMUFile timer support. |
| * Not in qemu-file.c to not add qemu-timer.c as dependency to qemu-file.c |
| */ |
| |
| void timer_put(QEMUFile *f, QEMUTimer *ts) |
| { |
| uint64_t expire_time; |
| |
| expire_time = timer_expire_time_ns(ts); |
| qemu_put_be64(f, expire_time); |
| } |
| |
| void timer_get(QEMUFile *f, QEMUTimer *ts) |
| { |
| uint64_t expire_time; |
| |
| expire_time = qemu_get_be64(f); |
| if (expire_time != -1) { |
| timer_mod_ns(ts, expire_time); |
| } else { |
| timer_del(ts); |
| } |
| } |
| |
| |
| /* VMState timer support. |
| * Not in vmstate.c to not add qemu-timer.c as dependency to vmstate.c |
| */ |
| |
| static int get_timer(QEMUFile *f, void *pv, size_t size, |
| const VMStateField *field) |
| { |
| QEMUTimer *v = pv; |
| timer_get(f, v); |
| return 0; |
| } |
| |
| static int put_timer(QEMUFile *f, void *pv, size_t size, |
| const VMStateField *field, JSONWriter *vmdesc) |
| { |
| QEMUTimer *v = pv; |
| timer_put(f, v); |
| |
| return 0; |
| } |
| |
| const VMStateInfo vmstate_info_timer = { |
| .name = "timer", |
| .get = get_timer, |
| .put = put_timer, |
| }; |
| |
| |
| typedef struct CompatEntry { |
| char idstr[256]; |
| int instance_id; |
| } CompatEntry; |
| |
| typedef struct SaveStateEntry { |
| QTAILQ_ENTRY(SaveStateEntry) entry; |
| char idstr[256]; |
| uint32_t instance_id; |
| int alias_id; |
| int version_id; |
| /* version id read from the stream */ |
| int load_version_id; |
| int section_id; |
| /* section id read from the stream */ |
| int load_section_id; |
| const SaveVMHandlers *ops; |
| const VMStateDescription *vmsd; |
| void *opaque; |
| CompatEntry *compat; |
| int is_ram; |
| } SaveStateEntry; |
| |
| typedef struct SaveState { |
| QTAILQ_HEAD(, SaveStateEntry) handlers; |
| SaveStateEntry *handler_pri_head[MIG_PRI_MAX + 1]; |
| int global_section_id; |
| uint32_t len; |
| const char *name; |
| uint32_t target_page_bits; |
| uint32_t caps_count; |
| MigrationCapability *capabilities; |
| QemuUUID uuid; |
| } SaveState; |
| |
| static SaveState savevm_state = { |
| .handlers = QTAILQ_HEAD_INITIALIZER(savevm_state.handlers), |
| .handler_pri_head = { [MIG_PRI_DEFAULT ... MIG_PRI_MAX] = NULL }, |
| .global_section_id = 0, |
| }; |
| |
| static SaveStateEntry *find_se(const char *idstr, uint32_t instance_id); |
| |
| static bool should_validate_capability(int capability) |
| { |
| assert(capability >= 0 && capability < MIGRATION_CAPABILITY__MAX); |
| /* Validate only new capabilities to keep compatibility. */ |
| switch (capability) { |
| case MIGRATION_CAPABILITY_X_IGNORE_SHARED: |
| case MIGRATION_CAPABILITY_MAPPED_RAM: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| static uint32_t get_validatable_capabilities_count(void) |
| { |
| MigrationState *s = migrate_get_current(); |
| uint32_t result = 0; |
| int i; |
| for (i = 0; i < MIGRATION_CAPABILITY__MAX; i++) { |
| if (should_validate_capability(i) && s->capabilities[i]) { |
| result++; |
| } |
| } |
| return result; |
| } |
| |
| static int configuration_pre_save(void *opaque) |
| { |
| SaveState *state = opaque; |
| const char *current_name = MACHINE_GET_CLASS(current_machine)->name; |
| MigrationState *s = migrate_get_current(); |
| int i, j; |
| |
| state->len = strlen(current_name); |
| state->name = current_name; |
| state->target_page_bits = qemu_target_page_bits(); |
| |
| state->caps_count = get_validatable_capabilities_count(); |
| state->capabilities = g_renew(MigrationCapability, state->capabilities, |
| state->caps_count); |
| for (i = j = 0; i < MIGRATION_CAPABILITY__MAX; i++) { |
| if (should_validate_capability(i) && s->capabilities[i]) { |
| state->capabilities[j++] = i; |
| } |
| } |
| state->uuid = qemu_uuid; |
| |
| return 0; |
| } |
| |
| static int configuration_post_save(void *opaque) |
| { |
| SaveState *state = opaque; |
| |
| g_free(state->capabilities); |
| state->capabilities = NULL; |
| state->caps_count = 0; |
| return 0; |
| } |
| |
| static int configuration_pre_load(void *opaque) |
| { |
| SaveState *state = opaque; |
| |
| /* If there is no target-page-bits subsection it means the source |
| * predates the variable-target-page-bits support and is using the |
| * minimum possible value for this CPU. |
| */ |
| state->target_page_bits = qemu_target_page_bits_min(); |
| return 0; |
| } |
| |
| static bool configuration_validate_capabilities(SaveState *state) |
| { |
| bool ret = true; |
| MigrationState *s = migrate_get_current(); |
| unsigned long *source_caps_bm; |
| int i; |
| |
| source_caps_bm = bitmap_new(MIGRATION_CAPABILITY__MAX); |
| for (i = 0; i < state->caps_count; i++) { |
| MigrationCapability capability = state->capabilities[i]; |
| set_bit(capability, source_caps_bm); |
| } |
| |
| for (i = 0; i < MIGRATION_CAPABILITY__MAX; i++) { |
| bool source_state, target_state; |
| if (!should_validate_capability(i)) { |
| continue; |
| } |
| source_state = test_bit(i, source_caps_bm); |
| target_state = s->capabilities[i]; |
| if (source_state != target_state) { |
| error_report("Capability %s is %s, but received capability is %s", |
| MigrationCapability_str(i), |
| target_state ? "on" : "off", |
| source_state ? "on" : "off"); |
| ret = false; |
| /* Don't break here to report all failed capabilities */ |
| } |
| } |
| |
| g_free(source_caps_bm); |
| return ret; |
| } |
| |
| static int configuration_post_load(void *opaque, int version_id) |
| { |
| SaveState *state = opaque; |
| const char *current_name = MACHINE_GET_CLASS(current_machine)->name; |
| int ret = 0; |
| |
| if (strncmp(state->name, current_name, state->len) != 0) { |
| error_report("Machine type received is '%.*s' and local is '%s'", |
| (int) state->len, state->name, current_name); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| if (state->target_page_bits != qemu_target_page_bits()) { |
| error_report("Received TARGET_PAGE_BITS is %d but local is %d", |
| state->target_page_bits, qemu_target_page_bits()); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| if (!configuration_validate_capabilities(state)) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| out: |
| g_free((void *)state->name); |
| state->name = NULL; |
| state->len = 0; |
| g_free(state->capabilities); |
| state->capabilities = NULL; |
| state->caps_count = 0; |
| |
| return ret; |
| } |
| |
| static int get_capability(QEMUFile *f, void *pv, size_t size, |
| const VMStateField *field) |
| { |
| MigrationCapability *capability = pv; |
| char capability_str[UINT8_MAX + 1]; |
| uint8_t len; |
| int i; |
| |
| len = qemu_get_byte(f); |
| qemu_get_buffer(f, (uint8_t *)capability_str, len); |
| capability_str[len] = '\0'; |
| for (i = 0; i < MIGRATION_CAPABILITY__MAX; i++) { |
| if (!strcmp(MigrationCapability_str(i), capability_str)) { |
| *capability = i; |
| return 0; |
| } |
| } |
| error_report("Received unknown capability %s", capability_str); |
| return -EINVAL; |
| } |
| |
| static int put_capability(QEMUFile *f, void *pv, size_t size, |
| const VMStateField *field, JSONWriter *vmdesc) |
| { |
| MigrationCapability *capability = pv; |
| const char *capability_str = MigrationCapability_str(*capability); |
| size_t len = strlen(capability_str); |
| assert(len <= UINT8_MAX); |
| |
| qemu_put_byte(f, len); |
| qemu_put_buffer(f, (uint8_t *)capability_str, len); |
| return 0; |
| } |
| |
| static const VMStateInfo vmstate_info_capability = { |
| .name = "capability", |
| .get = get_capability, |
| .put = put_capability, |
| }; |
| |
| /* The target-page-bits subsection is present only if the |
| * target page size is not the same as the default (ie the |
| * minimum page size for a variable-page-size guest CPU). |
| * If it is present then it contains the actual target page |
| * bits for the machine, and migration will fail if the |
| * two ends don't agree about it. |
| */ |
| static bool vmstate_target_page_bits_needed(void *opaque) |
| { |
| return qemu_target_page_bits() |
| > qemu_target_page_bits_min(); |
| } |
| |
| static const VMStateDescription vmstate_target_page_bits = { |
| .name = "configuration/target-page-bits", |
| .version_id = 1, |
| .minimum_version_id = 1, |
| .needed = vmstate_target_page_bits_needed, |
| .fields = (const VMStateField[]) { |
| VMSTATE_UINT32(target_page_bits, SaveState), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| static bool vmstate_capabilites_needed(void *opaque) |
| { |
| return get_validatable_capabilities_count() > 0; |
| } |
| |
| static const VMStateDescription vmstate_capabilites = { |
| .name = "configuration/capabilities", |
| .version_id = 1, |
| .minimum_version_id = 1, |
| .needed = vmstate_capabilites_needed, |
| .fields = (const VMStateField[]) { |
| VMSTATE_UINT32_V(caps_count, SaveState, 1), |
| VMSTATE_VARRAY_UINT32_ALLOC(capabilities, SaveState, caps_count, 1, |
| vmstate_info_capability, |
| MigrationCapability), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| static bool vmstate_uuid_needed(void *opaque) |
| { |
| return qemu_uuid_set && migrate_validate_uuid(); |
| } |
| |
| static int vmstate_uuid_post_load(void *opaque, int version_id) |
| { |
| SaveState *state = opaque; |
| char uuid_src[UUID_STR_LEN]; |
| char uuid_dst[UUID_STR_LEN]; |
| |
| if (!qemu_uuid_set) { |
| /* |
| * It's warning because user might not know UUID in some cases, |
| * e.g. load an old snapshot |
| */ |
| qemu_uuid_unparse(&state->uuid, uuid_src); |
| warn_report("UUID is received %s, but local uuid isn't set", |
| uuid_src); |
| return 0; |
| } |
| if (!qemu_uuid_is_equal(&state->uuid, &qemu_uuid)) { |
| qemu_uuid_unparse(&state->uuid, uuid_src); |
| qemu_uuid_unparse(&qemu_uuid, uuid_dst); |
| error_report("UUID received is %s and local is %s", uuid_src, uuid_dst); |
| return -EINVAL; |
| } |
| return 0; |
| } |
| |
| static const VMStateDescription vmstate_uuid = { |
| .name = "configuration/uuid", |
| .version_id = 1, |
| .minimum_version_id = 1, |
| .needed = vmstate_uuid_needed, |
| .post_load = vmstate_uuid_post_load, |
| .fields = (const VMStateField[]) { |
| VMSTATE_UINT8_ARRAY_V(uuid.data, SaveState, sizeof(QemuUUID), 1), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| static const VMStateDescription vmstate_configuration = { |
| .name = "configuration", |
| .version_id = 1, |
| .pre_load = configuration_pre_load, |
| .post_load = configuration_post_load, |
| .pre_save = configuration_pre_save, |
| .post_save = configuration_post_save, |
| .fields = (const VMStateField[]) { |
| VMSTATE_UINT32(len, SaveState), |
| VMSTATE_VBUFFER_ALLOC_UINT32(name, SaveState, 0, NULL, len), |
| VMSTATE_END_OF_LIST() |
| }, |
| .subsections = (const VMStateDescription * const []) { |
| &vmstate_target_page_bits, |
| &vmstate_capabilites, |
| &vmstate_uuid, |
| NULL |
| } |
| }; |
| |
| static void dump_vmstate_vmsd(FILE *out_file, |
| const VMStateDescription *vmsd, int indent, |
| bool is_subsection); |
| |
| static void dump_vmstate_vmsf(FILE *out_file, const VMStateField *field, |
| int indent) |
| { |
| fprintf(out_file, "%*s{\n", indent, ""); |
| indent += 2; |
| fprintf(out_file, "%*s\"field\": \"%s\",\n", indent, "", field->name); |
| fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "", |
| field->version_id); |
| fprintf(out_file, "%*s\"field_exists\": %s,\n", indent, "", |
| field->field_exists ? "true" : "false"); |
| if (field->flags & VMS_ARRAY) { |
| fprintf(out_file, "%*s\"num\": %d,\n", indent, "", field->num); |
| } |
| fprintf(out_file, "%*s\"size\": %zu", indent, "", field->size); |
| if (field->vmsd != NULL) { |
| fprintf(out_file, ",\n"); |
| dump_vmstate_vmsd(out_file, field->vmsd, indent, false); |
| } |
| fprintf(out_file, "\n%*s}", indent - 2, ""); |
| } |
| |
| static void dump_vmstate_vmss(FILE *out_file, |
| const VMStateDescription *subsection, |
| int indent) |
| { |
| if (subsection != NULL) { |
| dump_vmstate_vmsd(out_file, subsection, indent, true); |
| } |
| } |
| |
| static void dump_vmstate_vmsd(FILE *out_file, |
| const VMStateDescription *vmsd, int indent, |
| bool is_subsection) |
| { |
| if (is_subsection) { |
| fprintf(out_file, "%*s{\n", indent, ""); |
| } else { |
| fprintf(out_file, "%*s\"%s\": {\n", indent, "", "Description"); |
| } |
| indent += 2; |
| fprintf(out_file, "%*s\"name\": \"%s\",\n", indent, "", vmsd->name); |
| fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "", |
| vmsd->version_id); |
| fprintf(out_file, "%*s\"minimum_version_id\": %d", indent, "", |
| vmsd->minimum_version_id); |
| if (vmsd->fields != NULL) { |
| const VMStateField *field = vmsd->fields; |
| bool first; |
| |
| fprintf(out_file, ",\n%*s\"Fields\": [\n", indent, ""); |
| first = true; |
| while (field->name != NULL) { |
| if (field->flags & VMS_MUST_EXIST) { |
| /* Ignore VMSTATE_VALIDATE bits; these don't get migrated */ |
| field++; |
| continue; |
| } |
| if (!first) { |
| fprintf(out_file, ",\n"); |
| } |
| dump_vmstate_vmsf(out_file, field, indent + 2); |
| field++; |
| first = false; |
| } |
| assert(field->flags == VMS_END); |
| fprintf(out_file, "\n%*s]", indent, ""); |
| } |
| if (vmsd->subsections != NULL) { |
| const VMStateDescription * const *subsection = vmsd->subsections; |
| bool first; |
| |
| fprintf(out_file, ",\n%*s\"Subsections\": [\n", indent, ""); |
| first = true; |
| while (*subsection != NULL) { |
| if (!first) { |
| fprintf(out_file, ",\n"); |
| } |
| dump_vmstate_vmss(out_file, *subsection, indent + 2); |
| subsection++; |
| first = false; |
| } |
| fprintf(out_file, "\n%*s]", indent, ""); |
| } |
| fprintf(out_file, "\n%*s}", indent - 2, ""); |
| } |
| |
| static void dump_machine_type(FILE *out_file) |
| { |
| MachineClass *mc; |
| |
| mc = MACHINE_GET_CLASS(current_machine); |
| |
| fprintf(out_file, " \"vmschkmachine\": {\n"); |
| fprintf(out_file, " \"Name\": \"%s\"\n", mc->name); |
| fprintf(out_file, " },\n"); |
| } |
| |
| void dump_vmstate_json_to_file(FILE *out_file) |
| { |
| GSList *list, *elt; |
| bool first; |
| |
| fprintf(out_file, "{\n"); |
| dump_machine_type(out_file); |
| |
| first = true; |
| list = object_class_get_list(TYPE_DEVICE, true); |
| for (elt = list; elt; elt = elt->next) { |
| DeviceClass *dc = OBJECT_CLASS_CHECK(DeviceClass, elt->data, |
| TYPE_DEVICE); |
| const char *name; |
| int indent = 2; |
| |
| if (!dc->vmsd) { |
| continue; |
| } |
| |
| if (!first) { |
| fprintf(out_file, ",\n"); |
| } |
| name = object_class_get_name(OBJECT_CLASS(dc)); |
| fprintf(out_file, "%*s\"%s\": {\n", indent, "", name); |
| indent += 2; |
| fprintf(out_file, "%*s\"Name\": \"%s\",\n", indent, "", name); |
| fprintf(out_file, "%*s\"version_id\": %d,\n", indent, "", |
| dc->vmsd->version_id); |
| fprintf(out_file, "%*s\"minimum_version_id\": %d,\n", indent, "", |
| dc->vmsd->minimum_version_id); |
| |
| dump_vmstate_vmsd(out_file, dc->vmsd, indent, false); |
| |
| fprintf(out_file, "\n%*s}", indent - 2, ""); |
| first = false; |
| } |
| fprintf(out_file, "\n}\n"); |
| fclose(out_file); |
| g_slist_free(list); |
| } |
| |
| static uint32_t calculate_new_instance_id(const char *idstr) |
| { |
| SaveStateEntry *se; |
| uint32_t instance_id = 0; |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (strcmp(idstr, se->idstr) == 0 |
| && instance_id <= se->instance_id) { |
| instance_id = se->instance_id + 1; |
| } |
| } |
| /* Make sure we never loop over without being noticed */ |
| assert(instance_id != VMSTATE_INSTANCE_ID_ANY); |
| return instance_id; |
| } |
| |
| static int calculate_compat_instance_id(const char *idstr) |
| { |
| SaveStateEntry *se; |
| int instance_id = 0; |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (!se->compat) { |
| continue; |
| } |
| |
| if (strcmp(idstr, se->compat->idstr) == 0 |
| && instance_id <= se->compat->instance_id) { |
| instance_id = se->compat->instance_id + 1; |
| } |
| } |
| return instance_id; |
| } |
| |
| static inline MigrationPriority save_state_priority(SaveStateEntry *se) |
| { |
| if (se->vmsd) { |
| return se->vmsd->priority; |
| } |
| return MIG_PRI_DEFAULT; |
| } |
| |
| static void savevm_state_handler_insert(SaveStateEntry *nse) |
| { |
| MigrationPriority priority = save_state_priority(nse); |
| SaveStateEntry *se; |
| int i; |
| |
| assert(priority <= MIG_PRI_MAX); |
| |
| /* |
| * This should never happen otherwise migration will probably fail |
| * silently somewhere because we can be wrongly applying one |
| * object properties upon another one. Bail out ASAP. |
| */ |
| if (find_se(nse->idstr, nse->instance_id)) { |
| error_report("%s: Detected duplicate SaveStateEntry: " |
| "id=%s, instance_id=0x%"PRIx32, __func__, |
| nse->idstr, nse->instance_id); |
| exit(EXIT_FAILURE); |
| } |
| |
| for (i = priority - 1; i >= 0; i--) { |
| se = savevm_state.handler_pri_head[i]; |
| if (se != NULL) { |
| assert(save_state_priority(se) < priority); |
| break; |
| } |
| } |
| |
| if (i >= 0) { |
| QTAILQ_INSERT_BEFORE(se, nse, entry); |
| } else { |
| QTAILQ_INSERT_TAIL(&savevm_state.handlers, nse, entry); |
| } |
| |
| if (savevm_state.handler_pri_head[priority] == NULL) { |
| savevm_state.handler_pri_head[priority] = nse; |
| } |
| } |
| |
| static void savevm_state_handler_remove(SaveStateEntry *se) |
| { |
| SaveStateEntry *next; |
| MigrationPriority priority = save_state_priority(se); |
| |
| if (se == savevm_state.handler_pri_head[priority]) { |
| next = QTAILQ_NEXT(se, entry); |
| if (next != NULL && save_state_priority(next) == priority) { |
| savevm_state.handler_pri_head[priority] = next; |
| } else { |
| savevm_state.handler_pri_head[priority] = NULL; |
| } |
| } |
| QTAILQ_REMOVE(&savevm_state.handlers, se, entry); |
| } |
| |
| /* TODO: Individual devices generally have very little idea about the rest |
| of the system, so instance_id should be removed/replaced. |
| Meanwhile pass -1 as instance_id if you do not already have a clearly |
| distinguishing id for all instances of your device class. */ |
| int register_savevm_live(const char *idstr, |
| uint32_t instance_id, |
| int version_id, |
| const SaveVMHandlers *ops, |
| void *opaque) |
| { |
| SaveStateEntry *se; |
| |
| se = g_new0(SaveStateEntry, 1); |
| se->version_id = version_id; |
| se->section_id = savevm_state.global_section_id++; |
| se->ops = ops; |
| se->opaque = opaque; |
| se->vmsd = NULL; |
| /* if this is a live_savem then set is_ram */ |
| if (ops->save_setup != NULL) { |
| se->is_ram = 1; |
| } |
| |
| pstrcat(se->idstr, sizeof(se->idstr), idstr); |
| |
| if (instance_id == VMSTATE_INSTANCE_ID_ANY) { |
| se->instance_id = calculate_new_instance_id(se->idstr); |
| } else { |
| se->instance_id = instance_id; |
| } |
| assert(!se->compat || se->instance_id == 0); |
| savevm_state_handler_insert(se); |
| return 0; |
| } |
| |
| void unregister_savevm(VMStateIf *obj, const char *idstr, void *opaque) |
| { |
| SaveStateEntry *se, *new_se; |
| char id[256] = ""; |
| |
| if (obj) { |
| char *oid = vmstate_if_get_id(obj); |
| if (oid) { |
| pstrcpy(id, sizeof(id), oid); |
| pstrcat(id, sizeof(id), "/"); |
| g_free(oid); |
| } |
| } |
| pstrcat(id, sizeof(id), idstr); |
| |
| QTAILQ_FOREACH_SAFE(se, &savevm_state.handlers, entry, new_se) { |
| if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) { |
| savevm_state_handler_remove(se); |
| g_free(se->compat); |
| g_free(se); |
| } |
| } |
| } |
| |
| /* |
| * Perform some basic checks on vmsd's at registration |
| * time. |
| */ |
| static void vmstate_check(const VMStateDescription *vmsd) |
| { |
| const VMStateField *field = vmsd->fields; |
| const VMStateDescription * const *subsection = vmsd->subsections; |
| |
| if (field) { |
| while (field->name) { |
| if (field->flags & (VMS_STRUCT | VMS_VSTRUCT)) { |
| /* Recurse to sub structures */ |
| vmstate_check(field->vmsd); |
| } |
| /* Carry on */ |
| field++; |
| } |
| /* Check for the end of field list canary */ |
| if (field->flags != VMS_END) { |
| error_report("VMSTATE not ending with VMS_END: %s", vmsd->name); |
| g_assert_not_reached(); |
| } |
| } |
| |
| while (subsection && *subsection) { |
| /* |
| * The name of a subsection should start with the name of the |
| * current object. |
| */ |
| assert(!strncmp(vmsd->name, (*subsection)->name, strlen(vmsd->name))); |
| vmstate_check(*subsection); |
| subsection++; |
| } |
| } |
| |
| /* |
| * See comment in hw/intc/xics.c:icp_realize() |
| * |
| * This function can be removed when |
| * pre_2_10_vmstate_register_dummy_icp() is removed. |
| */ |
| int vmstate_replace_hack_for_ppc(VMStateIf *obj, int instance_id, |
| const VMStateDescription *vmsd, |
| void *opaque) |
| { |
| SaveStateEntry *se = find_se(vmsd->name, instance_id); |
| |
| if (se) { |
| savevm_state_handler_remove(se); |
| } |
| return vmstate_register(obj, instance_id, vmsd, opaque); |
| } |
| |
| int vmstate_register_with_alias_id(VMStateIf *obj, uint32_t instance_id, |
| const VMStateDescription *vmsd, |
| void *opaque, int alias_id, |
| int required_for_version, |
| Error **errp) |
| { |
| SaveStateEntry *se; |
| |
| /* If this triggers, alias support can be dropped for the vmsd. */ |
| assert(alias_id == -1 || required_for_version >= vmsd->minimum_version_id); |
| |
| se = g_new0(SaveStateEntry, 1); |
| se->version_id = vmsd->version_id; |
| se->section_id = savevm_state.global_section_id++; |
| se->opaque = opaque; |
| se->vmsd = vmsd; |
| se->alias_id = alias_id; |
| |
| if (obj) { |
| char *id = vmstate_if_get_id(obj); |
| if (id) { |
| if (snprintf(se->idstr, sizeof(se->idstr), "%s/", id) >= |
| sizeof(se->idstr)) { |
| error_setg(errp, "Path too long for VMState (%s)", id); |
| g_free(id); |
| g_free(se); |
| |
| return -1; |
| } |
| g_free(id); |
| |
| se->compat = g_new0(CompatEntry, 1); |
| pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), vmsd->name); |
| se->compat->instance_id = instance_id == VMSTATE_INSTANCE_ID_ANY ? |
| calculate_compat_instance_id(vmsd->name) : instance_id; |
| instance_id = VMSTATE_INSTANCE_ID_ANY; |
| } |
| } |
| pstrcat(se->idstr, sizeof(se->idstr), vmsd->name); |
| |
| if (instance_id == VMSTATE_INSTANCE_ID_ANY) { |
| se->instance_id = calculate_new_instance_id(se->idstr); |
| } else { |
| se->instance_id = instance_id; |
| } |
| |
| /* Perform a recursive sanity check during the test runs */ |
| if (qtest_enabled()) { |
| vmstate_check(vmsd); |
| } |
| assert(!se->compat || se->instance_id == 0); |
| savevm_state_handler_insert(se); |
| return 0; |
| } |
| |
| void vmstate_unregister(VMStateIf *obj, const VMStateDescription *vmsd, |
| void *opaque) |
| { |
| SaveStateEntry *se, *new_se; |
| |
| QTAILQ_FOREACH_SAFE(se, &savevm_state.handlers, entry, new_se) { |
| if (se->vmsd == vmsd && se->opaque == opaque) { |
| savevm_state_handler_remove(se); |
| g_free(se->compat); |
| g_free(se); |
| } |
| } |
| } |
| |
| static int vmstate_load(QEMUFile *f, SaveStateEntry *se) |
| { |
| trace_vmstate_load(se->idstr, se->vmsd ? se->vmsd->name : "(old)"); |
| if (!se->vmsd) { /* Old style */ |
| return se->ops->load_state(f, se->opaque, se->load_version_id); |
| } |
| return vmstate_load_state(f, se->vmsd, se->opaque, se->load_version_id); |
| } |
| |
| static void vmstate_save_old_style(QEMUFile *f, SaveStateEntry *se, |
| JSONWriter *vmdesc) |
| { |
| uint64_t old_offset = qemu_file_transferred(f); |
| se->ops->save_state(f, se->opaque); |
| uint64_t size = qemu_file_transferred(f) - old_offset; |
| |
| if (vmdesc) { |
| json_writer_int64(vmdesc, "size", size); |
| json_writer_start_array(vmdesc, "fields"); |
| json_writer_start_object(vmdesc, NULL); |
| json_writer_str(vmdesc, "name", "data"); |
| json_writer_int64(vmdesc, "size", size); |
| json_writer_str(vmdesc, "type", "buffer"); |
| json_writer_end_object(vmdesc); |
| json_writer_end_array(vmdesc); |
| } |
| } |
| |
| /* |
| * Write the header for device section (QEMU_VM_SECTION START/END/PART/FULL) |
| */ |
| static void save_section_header(QEMUFile *f, SaveStateEntry *se, |
| uint8_t section_type) |
| { |
| qemu_put_byte(f, section_type); |
| qemu_put_be32(f, se->section_id); |
| |
| if (section_type == QEMU_VM_SECTION_FULL || |
| section_type == QEMU_VM_SECTION_START) { |
| /* ID string */ |
| size_t len = strlen(se->idstr); |
| qemu_put_byte(f, len); |
| qemu_put_buffer(f, (uint8_t *)se->idstr, len); |
| |
| qemu_put_be32(f, se->instance_id); |
| qemu_put_be32(f, se->version_id); |
| } |
| } |
| |
| /* |
| * Write a footer onto device sections that catches cases misformatted device |
| * sections. |
| */ |
| static void save_section_footer(QEMUFile *f, SaveStateEntry *se) |
| { |
| if (migrate_get_current()->send_section_footer) { |
| qemu_put_byte(f, QEMU_VM_SECTION_FOOTER); |
| qemu_put_be32(f, se->section_id); |
| } |
| } |
| |
| static int vmstate_save(QEMUFile *f, SaveStateEntry *se, JSONWriter *vmdesc, |
| Error **errp) |
| { |
| int ret; |
| |
| if ((!se->ops || !se->ops->save_state) && !se->vmsd) { |
| return 0; |
| } |
| if (se->vmsd && !vmstate_section_needed(se->vmsd, se->opaque)) { |
| trace_savevm_section_skip(se->idstr, se->section_id); |
| return 0; |
| } |
| |
| trace_savevm_section_start(se->idstr, se->section_id); |
| save_section_header(f, se, QEMU_VM_SECTION_FULL); |
| if (vmdesc) { |
| json_writer_start_object(vmdesc, NULL); |
| json_writer_str(vmdesc, "name", se->idstr); |
| json_writer_int64(vmdesc, "instance_id", se->instance_id); |
| } |
| |
| trace_vmstate_save(se->idstr, se->vmsd ? se->vmsd->name : "(old)"); |
| if (!se->vmsd) { |
| vmstate_save_old_style(f, se, vmdesc); |
| } else { |
| ret = vmstate_save_state_with_err(f, se->vmsd, se->opaque, vmdesc, |
| errp); |
| if (ret) { |
| return ret; |
| } |
| } |
| |
| trace_savevm_section_end(se->idstr, se->section_id, 0); |
| save_section_footer(f, se); |
| if (vmdesc) { |
| json_writer_end_object(vmdesc); |
| } |
| return 0; |
| } |
| /** |
| * qemu_savevm_command_send: Send a 'QEMU_VM_COMMAND' type element with the |
| * command and associated data. |
| * |
| * @f: File to send command on |
| * @command: Command type to send |
| * @len: Length of associated data |
| * @data: Data associated with command. |
| */ |
| static void qemu_savevm_command_send(QEMUFile *f, |
| enum qemu_vm_cmd command, |
| uint16_t len, |
| uint8_t *data) |
| { |
| trace_savevm_command_send(command, len); |
| qemu_put_byte(f, QEMU_VM_COMMAND); |
| qemu_put_be16(f, (uint16_t)command); |
| qemu_put_be16(f, len); |
| qemu_put_buffer(f, data, len); |
| qemu_fflush(f); |
| } |
| |
| void qemu_savevm_send_colo_enable(QEMUFile *f) |
| { |
| trace_savevm_send_colo_enable(); |
| qemu_savevm_command_send(f, MIG_CMD_ENABLE_COLO, 0, NULL); |
| } |
| |
| void qemu_savevm_send_ping(QEMUFile *f, uint32_t value) |
| { |
| uint32_t buf; |
| |
| trace_savevm_send_ping(value); |
| buf = cpu_to_be32(value); |
| qemu_savevm_command_send(f, MIG_CMD_PING, sizeof(value), (uint8_t *)&buf); |
| } |
| |
| void qemu_savevm_send_open_return_path(QEMUFile *f) |
| { |
| trace_savevm_send_open_return_path(); |
| qemu_savevm_command_send(f, MIG_CMD_OPEN_RETURN_PATH, 0, NULL); |
| } |
| |
| /* We have a buffer of data to send; we don't want that all to be loaded |
| * by the command itself, so the command contains just the length of the |
| * extra buffer that we then send straight after it. |
| * TODO: Must be a better way to organise that |
| * |
| * Returns: |
| * 0 on success |
| * -ve on error |
| */ |
| int qemu_savevm_send_packaged(QEMUFile *f, const uint8_t *buf, size_t len) |
| { |
| uint32_t tmp; |
| MigrationState *ms = migrate_get_current(); |
| Error *local_err = NULL; |
| |
| if (len > MAX_VM_CMD_PACKAGED_SIZE) { |
| error_setg(&local_err, "%s: Unreasonably large packaged state: %zu", |
| __func__, len); |
| migrate_set_error(ms, local_err); |
| error_report_err(local_err); |
| return -1; |
| } |
| |
| tmp = cpu_to_be32(len); |
| |
| trace_qemu_savevm_send_packaged(); |
| qemu_savevm_command_send(f, MIG_CMD_PACKAGED, 4, (uint8_t *)&tmp); |
| |
| qemu_put_buffer(f, buf, len); |
| |
| return 0; |
| } |
| |
| /* Send prior to any postcopy transfer */ |
| void qemu_savevm_send_postcopy_advise(QEMUFile *f) |
| { |
| if (migrate_postcopy_ram()) { |
| uint64_t tmp[2]; |
| tmp[0] = cpu_to_be64(ram_pagesize_summary()); |
| tmp[1] = cpu_to_be64(qemu_target_page_size()); |
| |
| trace_qemu_savevm_send_postcopy_advise(); |
| qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_ADVISE, |
| 16, (uint8_t *)tmp); |
| } else { |
| qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_ADVISE, 0, NULL); |
| } |
| } |
| |
| /* Sent prior to starting the destination running in postcopy, discard pages |
| * that have already been sent but redirtied on the source. |
| * CMD_POSTCOPY_RAM_DISCARD consist of: |
| * byte version (0) |
| * byte Length of name field (not including 0) |
| * n x byte RAM block name |
| * byte 0 terminator (just for safety) |
| * n x Byte ranges within the named RAMBlock |
| * be64 Start of the range |
| * be64 Length |
| * |
| * name: RAMBlock name that these entries are part of |
| * len: Number of page entries |
| * start_list: 'len' addresses |
| * length_list: 'len' addresses |
| * |
| */ |
| void qemu_savevm_send_postcopy_ram_discard(QEMUFile *f, const char *name, |
| uint16_t len, |
| uint64_t *start_list, |
| uint64_t *length_list) |
| { |
| uint8_t *buf; |
| uint16_t tmplen; |
| uint16_t t; |
| size_t name_len = strlen(name); |
| |
| trace_qemu_savevm_send_postcopy_ram_discard(name, len); |
| assert(name_len < 256); |
| buf = g_malloc0(1 + 1 + name_len + 1 + (8 + 8) * len); |
| buf[0] = postcopy_ram_discard_version; |
| buf[1] = name_len; |
| memcpy(buf + 2, name, name_len); |
| tmplen = 2 + name_len; |
| buf[tmplen++] = '\0'; |
| |
| for (t = 0; t < len; t++) { |
| stq_be_p(buf + tmplen, start_list[t]); |
| tmplen += 8; |
| stq_be_p(buf + tmplen, length_list[t]); |
| tmplen += 8; |
| } |
| qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_RAM_DISCARD, tmplen, buf); |
| g_free(buf); |
| } |
| |
| /* Get the destination into a state where it can receive postcopy data. */ |
| void qemu_savevm_send_postcopy_listen(QEMUFile *f) |
| { |
| trace_savevm_send_postcopy_listen(); |
| qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_LISTEN, 0, NULL); |
| } |
| |
| /* Kick the destination into running */ |
| void qemu_savevm_send_postcopy_run(QEMUFile *f) |
| { |
| trace_savevm_send_postcopy_run(); |
| qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_RUN, 0, NULL); |
| } |
| |
| void qemu_savevm_send_postcopy_resume(QEMUFile *f) |
| { |
| trace_savevm_send_postcopy_resume(); |
| qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_RESUME, 0, NULL); |
| } |
| |
| void qemu_savevm_send_recv_bitmap(QEMUFile *f, char *block_name) |
| { |
| size_t len; |
| char buf[256]; |
| |
| trace_savevm_send_recv_bitmap(block_name); |
| |
| buf[0] = len = strlen(block_name); |
| memcpy(buf + 1, block_name, len); |
| |
| qemu_savevm_command_send(f, MIG_CMD_RECV_BITMAP, len + 1, (uint8_t *)buf); |
| } |
| |
| bool qemu_savevm_state_blocked(Error **errp) |
| { |
| SaveStateEntry *se; |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (se->vmsd && se->vmsd->unmigratable) { |
| error_setg(errp, "State blocked by non-migratable device '%s'", |
| se->idstr); |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| void qemu_savevm_non_migratable_list(strList **reasons) |
| { |
| SaveStateEntry *se; |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (se->vmsd && se->vmsd->unmigratable) { |
| QAPI_LIST_PREPEND(*reasons, |
| g_strdup_printf("non-migratable device: %s", |
| se->idstr)); |
| } |
| } |
| } |
| |
| void qemu_savevm_state_header(QEMUFile *f) |
| { |
| MigrationState *s = migrate_get_current(); |
| |
| s->vmdesc = json_writer_new(false); |
| |
| trace_savevm_state_header(); |
| qemu_put_be32(f, QEMU_VM_FILE_MAGIC); |
| qemu_put_be32(f, QEMU_VM_FILE_VERSION); |
| |
| if (s->send_configuration) { |
| qemu_put_byte(f, QEMU_VM_CONFIGURATION); |
| |
| /* |
| * This starts the main json object and is paired with the |
| * json_writer_end_object in |
| * qemu_savevm_state_complete_precopy_non_iterable |
| */ |
| json_writer_start_object(s->vmdesc, NULL); |
| |
| json_writer_start_object(s->vmdesc, "configuration"); |
| vmstate_save_state(f, &vmstate_configuration, &savevm_state, s->vmdesc); |
| json_writer_end_object(s->vmdesc); |
| } |
| } |
| |
| bool qemu_savevm_state_guest_unplug_pending(void) |
| { |
| SaveStateEntry *se; |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (se->vmsd && se->vmsd->dev_unplug_pending && |
| se->vmsd->dev_unplug_pending(se->opaque)) { |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| int qemu_savevm_state_prepare(Error **errp) |
| { |
| SaveStateEntry *se; |
| int ret; |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (!se->ops || !se->ops->save_prepare) { |
| continue; |
| } |
| if (se->ops->is_active) { |
| if (!se->ops->is_active(se->opaque)) { |
| continue; |
| } |
| } |
| |
| ret = se->ops->save_prepare(se->opaque, errp); |
| if (ret < 0) { |
| return ret; |
| } |
| } |
| |
| return 0; |
| } |
| |
| int qemu_savevm_state_setup(QEMUFile *f, Error **errp) |
| { |
| ERRP_GUARD(); |
| MigrationState *ms = migrate_get_current(); |
| SaveStateEntry *se; |
| int ret = 0; |
| |
| json_writer_int64(ms->vmdesc, "page_size", qemu_target_page_size()); |
| json_writer_start_array(ms->vmdesc, "devices"); |
| |
| trace_savevm_state_setup(); |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (se->vmsd && se->vmsd->early_setup) { |
| ret = vmstate_save(f, se, ms->vmdesc, errp); |
| if (ret) { |
| migrate_set_error(ms, *errp); |
| qemu_file_set_error(f, ret); |
| break; |
| } |
| continue; |
| } |
| |
| if (!se->ops || !se->ops->save_setup) { |
| continue; |
| } |
| if (se->ops->is_active) { |
| if (!se->ops->is_active(se->opaque)) { |
| continue; |
| } |
| } |
| save_section_header(f, se, QEMU_VM_SECTION_START); |
| |
| ret = se->ops->save_setup(f, se->opaque, errp); |
| save_section_footer(f, se); |
| if (ret < 0) { |
| qemu_file_set_error(f, ret); |
| break; |
| } |
| } |
| |
| if (ret) { |
| return ret; |
| } |
| |
| /* TODO: Should we check that errp is set in case of failure ? */ |
| return precopy_notify(PRECOPY_NOTIFY_SETUP, errp); |
| } |
| |
| int qemu_savevm_state_resume_prepare(MigrationState *s) |
| { |
| SaveStateEntry *se; |
| int ret; |
| |
| trace_savevm_state_resume_prepare(); |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (!se->ops || !se->ops->resume_prepare) { |
| continue; |
| } |
| if (se->ops->is_active) { |
| if (!se->ops->is_active(se->opaque)) { |
| continue; |
| } |
| } |
| ret = se->ops->resume_prepare(s, se->opaque); |
| if (ret < 0) { |
| return ret; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * this function has three return values: |
| * negative: there was one error, and we have -errno. |
| * 0 : We haven't finished, caller have to go again |
| * 1 : We have finished, we can go to complete phase |
| */ |
| int qemu_savevm_state_iterate(QEMUFile *f, bool postcopy) |
| { |
| SaveStateEntry *se; |
| bool all_finished = true; |
| int ret; |
| |
| trace_savevm_state_iterate(); |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (!se->ops || !se->ops->save_live_iterate) { |
| continue; |
| } |
| if (se->ops->is_active && |
| !se->ops->is_active(se->opaque)) { |
| continue; |
| } |
| if (se->ops->is_active_iterate && |
| !se->ops->is_active_iterate(se->opaque)) { |
| continue; |
| } |
| /* |
| * In the postcopy phase, any device that doesn't know how to |
| * do postcopy should have saved it's state in the _complete |
| * call that's already run, it might get confused if we call |
| * iterate afterwards. |
| */ |
| if (postcopy && |
| !(se->ops->has_postcopy && se->ops->has_postcopy(se->opaque))) { |
| continue; |
| } |
| if (migration_rate_exceeded(f)) { |
| return 0; |
| } |
| trace_savevm_section_start(se->idstr, se->section_id); |
| |
| save_section_header(f, se, QEMU_VM_SECTION_PART); |
| |
| ret = se->ops->save_live_iterate(f, se->opaque); |
| trace_savevm_section_end(se->idstr, se->section_id, ret); |
| save_section_footer(f, se); |
| |
| if (ret < 0) { |
| error_report("failed to save SaveStateEntry with id(name): " |
| "%d(%s): %d", |
| se->section_id, se->idstr, ret); |
| qemu_file_set_error(f, ret); |
| return ret; |
| } else if (!ret) { |
| all_finished = false; |
| } |
| } |
| return all_finished; |
| } |
| |
| static bool should_send_vmdesc(void) |
| { |
| MachineState *machine = MACHINE(qdev_get_machine()); |
| bool in_postcopy = migration_in_postcopy(); |
| return !machine->suppress_vmdesc && !in_postcopy; |
| } |
| |
| /* |
| * Calls the save_live_complete_postcopy methods |
| * causing the last few pages to be sent immediately and doing any associated |
| * cleanup. |
| * Note postcopy also calls qemu_savevm_state_complete_precopy to complete |
| * all the other devices, but that happens at the point we switch to postcopy. |
| */ |
| void qemu_savevm_state_complete_postcopy(QEMUFile *f) |
| { |
| SaveStateEntry *se; |
| int ret; |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (!se->ops || !se->ops->save_live_complete_postcopy) { |
| continue; |
| } |
| if (se->ops->is_active) { |
| if (!se->ops->is_active(se->opaque)) { |
| continue; |
| } |
| } |
| trace_savevm_section_start(se->idstr, se->section_id); |
| /* Section type */ |
| qemu_put_byte(f, QEMU_VM_SECTION_END); |
| qemu_put_be32(f, se->section_id); |
| |
| ret = se->ops->save_live_complete_postcopy(f, se->opaque); |
| trace_savevm_section_end(se->idstr, se->section_id, ret); |
| save_section_footer(f, se); |
| if (ret < 0) { |
| qemu_file_set_error(f, ret); |
| return; |
| } |
| } |
| |
| qemu_put_byte(f, QEMU_VM_EOF); |
| qemu_fflush(f); |
| } |
| |
| static |
| int qemu_savevm_state_complete_precopy_iterable(QEMUFile *f, bool in_postcopy) |
| { |
| int64_t start_ts_each, end_ts_each; |
| SaveStateEntry *se; |
| int ret; |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (!se->ops || |
| (in_postcopy && se->ops->has_postcopy && |
| se->ops->has_postcopy(se->opaque)) || |
| !se->ops->save_live_complete_precopy) { |
| continue; |
| } |
| |
| if (se->ops->is_active) { |
| if (!se->ops->is_active(se->opaque)) { |
| continue; |
| } |
| } |
| |
| start_ts_each = qemu_clock_get_us(QEMU_CLOCK_REALTIME); |
| trace_savevm_section_start(se->idstr, se->section_id); |
| |
| save_section_header(f, se, QEMU_VM_SECTION_END); |
| |
| ret = se->ops->save_live_complete_precopy(f, se->opaque); |
| trace_savevm_section_end(se->idstr, se->section_id, ret); |
| save_section_footer(f, se); |
| if (ret < 0) { |
| qemu_file_set_error(f, ret); |
| return -1; |
| } |
| end_ts_each = qemu_clock_get_us(QEMU_CLOCK_REALTIME); |
| trace_vmstate_downtime_save("iterable", se->idstr, se->instance_id, |
| end_ts_each - start_ts_each); |
| } |
| |
| trace_vmstate_downtime_checkpoint("src-iterable-saved"); |
| |
| return 0; |
| } |
| |
| int qemu_savevm_state_complete_precopy_non_iterable(QEMUFile *f, |
| bool in_postcopy, |
| bool inactivate_disks) |
| { |
| MigrationState *ms = migrate_get_current(); |
| int64_t start_ts_each, end_ts_each; |
| JSONWriter *vmdesc = ms->vmdesc; |
| int vmdesc_len; |
| SaveStateEntry *se; |
| Error *local_err = NULL; |
| int ret; |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (se->vmsd && se->vmsd->early_setup) { |
| /* Already saved during qemu_savevm_state_setup(). */ |
| continue; |
| } |
| |
| start_ts_each = qemu_clock_get_us(QEMU_CLOCK_REALTIME); |
| |
| ret = vmstate_save(f, se, vmdesc, &local_err); |
| if (ret) { |
| migrate_set_error(ms, local_err); |
| error_report_err(local_err); |
| qemu_file_set_error(f, ret); |
| return ret; |
| } |
| |
| end_ts_each = qemu_clock_get_us(QEMU_CLOCK_REALTIME); |
| trace_vmstate_downtime_save("non-iterable", se->idstr, se->instance_id, |
| end_ts_each - start_ts_each); |
| } |
| |
| if (inactivate_disks) { |
| /* Inactivate before sending QEMU_VM_EOF so that the |
| * bdrv_activate_all() on the other end won't fail. */ |
| ret = bdrv_inactivate_all(); |
| if (ret) { |
| error_setg(&local_err, "%s: bdrv_inactivate_all() failed (%d)", |
| __func__, ret); |
| migrate_set_error(ms, local_err); |
| error_report_err(local_err); |
| qemu_file_set_error(f, ret); |
| return ret; |
| } |
| } |
| if (!in_postcopy) { |
| /* Postcopy stream will still be going */ |
| qemu_put_byte(f, QEMU_VM_EOF); |
| } |
| |
| json_writer_end_array(vmdesc); |
| json_writer_end_object(vmdesc); |
| vmdesc_len = strlen(json_writer_get(vmdesc)); |
| |
| if (should_send_vmdesc()) { |
| qemu_put_byte(f, QEMU_VM_VMDESCRIPTION); |
| qemu_put_be32(f, vmdesc_len); |
| qemu_put_buffer(f, (uint8_t *)json_writer_get(vmdesc), vmdesc_len); |
| } |
| |
| /* Free it now to detect any inconsistencies. */ |
| json_writer_free(vmdesc); |
| ms->vmdesc = NULL; |
| |
| trace_vmstate_downtime_checkpoint("src-non-iterable-saved"); |
| |
| return 0; |
| } |
| |
| int qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only, |
| bool inactivate_disks) |
| { |
| int ret; |
| Error *local_err = NULL; |
| bool in_postcopy = migration_in_postcopy(); |
| |
| if (precopy_notify(PRECOPY_NOTIFY_COMPLETE, &local_err)) { |
| error_report_err(local_err); |
| } |
| |
| trace_savevm_state_complete_precopy(); |
| |
| cpu_synchronize_all_states(); |
| |
| if (!in_postcopy || iterable_only) { |
| ret = qemu_savevm_state_complete_precopy_iterable(f, in_postcopy); |
| if (ret) { |
| return ret; |
| } |
| } |
| |
| if (iterable_only) { |
| goto flush; |
| } |
| |
| ret = qemu_savevm_state_complete_precopy_non_iterable(f, in_postcopy, |
| inactivate_disks); |
| if (ret) { |
| return ret; |
| } |
| |
| flush: |
| return qemu_fflush(f); |
| } |
| |
| /* Give an estimate of the amount left to be transferred, |
| * the result is split into the amount for units that can and |
| * for units that can't do postcopy. |
| */ |
| void qemu_savevm_state_pending_estimate(uint64_t *must_precopy, |
| uint64_t *can_postcopy) |
| { |
| SaveStateEntry *se; |
| |
| *must_precopy = 0; |
| *can_postcopy = 0; |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (!se->ops || !se->ops->state_pending_estimate) { |
| continue; |
| } |
| if (se->ops->is_active) { |
| if (!se->ops->is_active(se->opaque)) { |
| continue; |
| } |
| } |
| se->ops->state_pending_estimate(se->opaque, must_precopy, can_postcopy); |
| } |
| } |
| |
| void qemu_savevm_state_pending_exact(uint64_t *must_precopy, |
| uint64_t *can_postcopy) |
| { |
| SaveStateEntry *se; |
| |
| *must_precopy = 0; |
| *can_postcopy = 0; |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (!se->ops || !se->ops->state_pending_exact) { |
| continue; |
| } |
| if (se->ops->is_active) { |
| if (!se->ops->is_active(se->opaque)) { |
| continue; |
| } |
| } |
| se->ops->state_pending_exact(se->opaque, must_precopy, can_postcopy); |
| } |
| } |
| |
| void qemu_savevm_state_cleanup(void) |
| { |
| SaveStateEntry *se; |
| Error *local_err = NULL; |
| |
| if (precopy_notify(PRECOPY_NOTIFY_CLEANUP, &local_err)) { |
| error_report_err(local_err); |
| } |
| |
| trace_savevm_state_cleanup(); |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (se->ops && se->ops->save_cleanup) { |
| se->ops->save_cleanup(se->opaque); |
| } |
| } |
| } |
| |
| static int qemu_savevm_state(QEMUFile *f, Error **errp) |
| { |
| int ret; |
| MigrationState *ms = migrate_get_current(); |
| MigrationStatus status; |
| |
| if (migration_is_running()) { |
| error_setg(errp, "There's a migration process in progress"); |
| return -EINVAL; |
| } |
| |
| ret = migrate_init(ms, errp); |
| if (ret) { |
| return ret; |
| } |
| ms->to_dst_file = f; |
| |
| qemu_savevm_state_header(f); |
| ret = qemu_savevm_state_setup(f, errp); |
| if (ret) { |
| goto cleanup; |
| } |
| |
| while (qemu_file_get_error(f) == 0) { |
| if (qemu_savevm_state_iterate(f, false) > 0) { |
| break; |
| } |
| } |
| |
| ret = qemu_file_get_error(f); |
| if (ret == 0) { |
| qemu_savevm_state_complete_precopy(f, false, false); |
| ret = qemu_file_get_error(f); |
| } |
| if (ret != 0) { |
| error_setg_errno(errp, -ret, "Error while writing VM state"); |
| } |
| cleanup: |
| qemu_savevm_state_cleanup(); |
| |
| if (ret != 0) { |
| status = MIGRATION_STATUS_FAILED; |
| } else { |
| status = MIGRATION_STATUS_COMPLETED; |
| } |
| migrate_set_state(&ms->state, MIGRATION_STATUS_SETUP, status); |
| |
| /* f is outer parameter, it should not stay in global migration state after |
| * this function finished */ |
| ms->to_dst_file = NULL; |
| |
| return ret; |
| } |
| |
| void qemu_savevm_live_state(QEMUFile *f) |
| { |
| /* save QEMU_VM_SECTION_END section */ |
| qemu_savevm_state_complete_precopy(f, true, false); |
| qemu_put_byte(f, QEMU_VM_EOF); |
| } |
| |
| int qemu_save_device_state(QEMUFile *f) |
| { |
| MigrationState *ms = migrate_get_current(); |
| Error *local_err = NULL; |
| SaveStateEntry *se; |
| |
| if (!migration_in_colo_state()) { |
| qemu_put_be32(f, QEMU_VM_FILE_MAGIC); |
| qemu_put_be32(f, QEMU_VM_FILE_VERSION); |
| } |
| cpu_synchronize_all_states(); |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| int ret; |
| |
| if (se->is_ram) { |
| continue; |
| } |
| ret = vmstate_save(f, se, NULL, &local_err); |
| if (ret) { |
| migrate_set_error(ms, local_err); |
| error_report_err(local_err); |
| return ret; |
| } |
| } |
| |
| qemu_put_byte(f, QEMU_VM_EOF); |
| |
| return qemu_file_get_error(f); |
| } |
| |
| static SaveStateEntry *find_se(const char *idstr, uint32_t instance_id) |
| { |
| SaveStateEntry *se; |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (!strcmp(se->idstr, idstr) && |
| (instance_id == se->instance_id || |
| instance_id == se->alias_id)) |
| return se; |
| /* Migrating from an older version? */ |
| if (strstr(se->idstr, idstr) && se->compat) { |
| if (!strcmp(se->compat->idstr, idstr) && |
| (instance_id == se->compat->instance_id || |
| instance_id == se->alias_id)) |
| return se; |
| } |
| } |
| return NULL; |
| } |
| |
| enum LoadVMExitCodes { |
| /* Allow a command to quit all layers of nested loadvm loops */ |
| LOADVM_QUIT = 1, |
| }; |
| |
| /* ------ incoming postcopy messages ------ */ |
| /* 'advise' arrives before any transfers just to tell us that a postcopy |
| * *might* happen - it might be skipped if precopy transferred everything |
| * quickly. |
| */ |
| static int loadvm_postcopy_handle_advise(MigrationIncomingState *mis, |
| uint16_t len) |
| { |
| PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_ADVISE); |
| uint64_t remote_pagesize_summary, local_pagesize_summary, remote_tps; |
| size_t page_size = qemu_target_page_size(); |
| Error *local_err = NULL; |
| |
| trace_loadvm_postcopy_handle_advise(); |
| if (ps != POSTCOPY_INCOMING_NONE) { |
| error_report("CMD_POSTCOPY_ADVISE in wrong postcopy state (%d)", ps); |
| return -1; |
| } |
| |
| switch (len) { |
| case 0: |
| if (migrate_postcopy_ram()) { |
| error_report("RAM postcopy is enabled but have 0 byte advise"); |
| return -EINVAL; |
| } |
| return 0; |
| case 8 + 8: |
| if (!migrate_postcopy_ram()) { |
| error_report("RAM postcopy is disabled but have 16 byte advise"); |
| return -EINVAL; |
| } |
| break; |
| default: |
| error_report("CMD_POSTCOPY_ADVISE invalid length (%d)", len); |
| return -EINVAL; |
| } |
| |
| if (!postcopy_ram_supported_by_host(mis, &local_err)) { |
| error_report_err(local_err); |
| postcopy_state_set(POSTCOPY_INCOMING_NONE); |
| return -1; |
| } |
| |
| remote_pagesize_summary = qemu_get_be64(mis->from_src_file); |
| local_pagesize_summary = ram_pagesize_summary(); |
| |
| if (remote_pagesize_summary != local_pagesize_summary) { |
| /* |
| * This detects two potential causes of mismatch: |
| * a) A mismatch in host page sizes |
| * Some combinations of mismatch are probably possible but it gets |
| * a bit more complicated. In particular we need to place whole |
| * host pages on the dest at once, and we need to ensure that we |
| * handle dirtying to make sure we never end up sending part of |
| * a hostpage on it's own. |
| * b) The use of different huge page sizes on source/destination |
| * a more fine grain test is performed during RAM block migration |
| * but this test here causes a nice early clear failure, and |
| * also fails when passed to an older qemu that doesn't |
| * do huge pages. |
| */ |
| error_report("Postcopy needs matching RAM page sizes (s=%" PRIx64 |
| " d=%" PRIx64 ")", |
| remote_pagesize_summary, local_pagesize_summary); |
| return -1; |
| } |
| |
| remote_tps = qemu_get_be64(mis->from_src_file); |
| if (remote_tps != page_size) { |
| /* |
| * Again, some differences could be dealt with, but for now keep it |
| * simple. |
| */ |
| error_report("Postcopy needs matching target page sizes (s=%d d=%zd)", |
| (int)remote_tps, page_size); |
| return -1; |
| } |
| |
| if (postcopy_notify(POSTCOPY_NOTIFY_INBOUND_ADVISE, &local_err)) { |
| error_report_err(local_err); |
| return -1; |
| } |
| |
| if (ram_postcopy_incoming_init(mis)) { |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| /* After postcopy we will be told to throw some pages away since they're |
| * dirty and will have to be demand fetched. Must happen before CPU is |
| * started. |
| * There can be 0..many of these messages, each encoding multiple pages. |
| */ |
| static int loadvm_postcopy_ram_handle_discard(MigrationIncomingState *mis, |
| uint16_t len) |
| { |
| int tmp; |
| char ramid[256]; |
| PostcopyState ps = postcopy_state_get(); |
| |
| trace_loadvm_postcopy_ram_handle_discard(); |
| |
| switch (ps) { |
| case POSTCOPY_INCOMING_ADVISE: |
| /* 1st discard */ |
| tmp = postcopy_ram_prepare_discard(mis); |
| if (tmp) { |
| return tmp; |
| } |
| break; |
| |
| case POSTCOPY_INCOMING_DISCARD: |
| /* Expected state */ |
| break; |
| |
| default: |
| error_report("CMD_POSTCOPY_RAM_DISCARD in wrong postcopy state (%d)", |
| ps); |
| return -1; |
| } |
| /* We're expecting a |
| * Version (0) |
| * a RAM ID string (length byte, name, 0 term) |
| * then at least 1 16 byte chunk |
| */ |
| if (len < (1 + 1 + 1 + 1 + 2 * 8)) { |
| error_report("CMD_POSTCOPY_RAM_DISCARD invalid length (%d)", len); |
| return -1; |
| } |
| |
| tmp = qemu_get_byte(mis->from_src_file); |
| if (tmp != postcopy_ram_discard_version) { |
| error_report("CMD_POSTCOPY_RAM_DISCARD invalid version (%d)", tmp); |
| return -1; |
| } |
| |
| if (!qemu_get_counted_string(mis->from_src_file, ramid)) { |
| error_report("CMD_POSTCOPY_RAM_DISCARD Failed to read RAMBlock ID"); |
| return -1; |
| } |
| tmp = qemu_get_byte(mis->from_src_file); |
| if (tmp != 0) { |
| error_report("CMD_POSTCOPY_RAM_DISCARD missing nil (%d)", tmp); |
| return -1; |
| } |
| |
| len -= 3 + strlen(ramid); |
| if (len % 16) { |
| error_report("CMD_POSTCOPY_RAM_DISCARD invalid length (%d)", len); |
| return -1; |
| } |
| trace_loadvm_postcopy_ram_handle_discard_header(ramid, len); |
| while (len) { |
| uint64_t start_addr, block_length; |
| start_addr = qemu_get_be64(mis->from_src_file); |
| block_length = qemu_get_be64(mis->from_src_file); |
| |
| len -= 16; |
| int ret = ram_discard_range(ramid, start_addr, block_length); |
| if (ret) { |
| return ret; |
| } |
| } |
| trace_loadvm_postcopy_ram_handle_discard_end(); |
| |
| return 0; |
| } |
| |
| /* |
| * Triggered by a postcopy_listen command; this thread takes over reading |
| * the input stream, leaving the main thread free to carry on loading the rest |
| * of the device state (from RAM). |
| * (TODO:This could do with being in a postcopy file - but there again it's |
| * just another input loop, not that postcopy specific) |
| */ |
| static void *postcopy_ram_listen_thread(void *opaque) |
| { |
| MigrationIncomingState *mis = migration_incoming_get_current(); |
| QEMUFile *f = mis->from_src_file; |
| int load_res; |
| MigrationState *migr = migrate_get_current(); |
| |
| object_ref(OBJECT(migr)); |
| |
| migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE, |
| MIGRATION_STATUS_POSTCOPY_ACTIVE); |
| qemu_sem_post(&mis->thread_sync_sem); |
| trace_postcopy_ram_listen_thread_start(); |
| |
| rcu_register_thread(); |
| /* |
| * Because we're a thread and not a coroutine we can't yield |
| * in qemu_file, and thus we must be blocking now. |
| */ |
| qemu_file_set_blocking(f, true); |
| load_res = qemu_loadvm_state_main(f, mis); |
| |
| /* |
| * This is tricky, but, mis->from_src_file can change after it |
| * returns, when postcopy recovery happened. In the future, we may |
| * want a wrapper for the QEMUFile handle. |
| */ |
| f = mis->from_src_file; |
| |
| /* And non-blocking again so we don't block in any cleanup */ |
| qemu_file_set_blocking(f, false); |
| |
| trace_postcopy_ram_listen_thread_exit(); |
| if (load_res < 0) { |
| qemu_file_set_error(f, load_res); |
| dirty_bitmap_mig_cancel_incoming(); |
| if (postcopy_state_get() == POSTCOPY_INCOMING_RUNNING && |
| !migrate_postcopy_ram() && migrate_dirty_bitmaps()) |
| { |
| error_report("%s: loadvm failed during postcopy: %d. All states " |
| "are migrated except dirty bitmaps. Some dirty " |
| "bitmaps may be lost, and present migrated dirty " |
| "bitmaps are correctly migrated and valid.", |
| __func__, load_res); |
| load_res = 0; /* prevent further exit() */ |
| } else { |
| error_report("%s: loadvm failed: %d", __func__, load_res); |
| migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, |
| MIGRATION_STATUS_FAILED); |
| } |
| } |
| if (load_res >= 0) { |
| /* |
| * This looks good, but it's possible that the device loading in the |
| * main thread hasn't finished yet, and so we might not be in 'RUN' |
| * state yet; wait for the end of the main thread. |
| */ |
| qemu_event_wait(&mis->main_thread_load_event); |
| } |
| postcopy_ram_incoming_cleanup(mis); |
| |
| if (load_res < 0) { |
| /* |
| * If something went wrong then we have a bad state so exit; |
| * depending how far we got it might be possible at this point |
| * to leave the guest running and fire MCEs for pages that never |
| * arrived as a desperate recovery step. |
| */ |
| rcu_unregister_thread(); |
| exit(EXIT_FAILURE); |
| } |
| |
| migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, |
| MIGRATION_STATUS_COMPLETED); |
| /* |
| * If everything has worked fine, then the main thread has waited |
| * for us to start, and we're the last use of the mis. |
| * (If something broke then qemu will have to exit anyway since it's |
| * got a bad migration state). |
| */ |
| migration_incoming_state_destroy(); |
| qemu_loadvm_state_cleanup(); |
| |
| rcu_unregister_thread(); |
| mis->have_listen_thread = false; |
| postcopy_state_set(POSTCOPY_INCOMING_END); |
| |
| object_unref(OBJECT(migr)); |
| |
| return NULL; |
| } |
| |
| /* After this message we must be able to immediately receive postcopy data */ |
| static int loadvm_postcopy_handle_listen(MigrationIncomingState *mis) |
| { |
| PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_LISTENING); |
| Error *local_err = NULL; |
| |
| trace_loadvm_postcopy_handle_listen("enter"); |
| |
| if (ps != POSTCOPY_INCOMING_ADVISE && ps != POSTCOPY_INCOMING_DISCARD) { |
| error_report("CMD_POSTCOPY_LISTEN in wrong postcopy state (%d)", ps); |
| return -1; |
| } |
| if (ps == POSTCOPY_INCOMING_ADVISE) { |
| /* |
| * A rare case, we entered listen without having to do any discards, |
| * so do the setup that's normally done at the time of the 1st discard. |
| */ |
| if (migrate_postcopy_ram()) { |
| postcopy_ram_prepare_discard(mis); |
| } |
| } |
| |
| trace_loadvm_postcopy_handle_listen("after discard"); |
| |
| /* |
| * Sensitise RAM - can now generate requests for blocks that don't exist |
| * However, at this point the CPU shouldn't be running, and the IO |
| * shouldn't be doing anything yet so don't actually expect requests |
| */ |
| if (migrate_postcopy_ram()) { |
| if (postcopy_ram_incoming_setup(mis)) { |
| postcopy_ram_incoming_cleanup(mis); |
| return -1; |
| } |
| } |
| |
| trace_loadvm_postcopy_handle_listen("after uffd"); |
| |
| if (postcopy_notify(POSTCOPY_NOTIFY_INBOUND_LISTEN, &local_err)) { |
| error_report_err(local_err); |
| return -1; |
| } |
| |
| mis->have_listen_thread = true; |
| postcopy_thread_create(mis, &mis->listen_thread, "postcopy/listen", |
| postcopy_ram_listen_thread, QEMU_THREAD_DETACHED); |
| trace_loadvm_postcopy_handle_listen("return"); |
| |
| return 0; |
| } |
| |
| static void loadvm_postcopy_handle_run_bh(void *opaque) |
| { |
| Error *local_err = NULL; |
| MigrationIncomingState *mis = opaque; |
| |
| trace_vmstate_downtime_checkpoint("dst-postcopy-bh-enter"); |
| |
| /* TODO we should move all of this lot into postcopy_ram.c or a shared code |
| * in migration.c |
| */ |
| cpu_synchronize_all_post_init(); |
| |
| trace_vmstate_downtime_checkpoint("dst-postcopy-bh-cpu-synced"); |
| |
| qemu_announce_self(&mis->announce_timer, migrate_announce_params()); |
| |
| trace_vmstate_downtime_checkpoint("dst-postcopy-bh-announced"); |
| |
| /* Make sure all file formats throw away their mutable metadata. |
| * If we get an error here, just don't restart the VM yet. */ |
| bdrv_activate_all(&local_err); |
| if (local_err) { |
| error_report_err(local_err); |
| local_err = NULL; |
| autostart = false; |
| } |
| |
| trace_vmstate_downtime_checkpoint("dst-postcopy-bh-cache-invalidated"); |
| |
| dirty_bitmap_mig_before_vm_start(); |
| |
| if (autostart) { |
| /* Hold onto your hats, starting the CPU */ |
| vm_start(); |
| } else { |
| /* leave it paused and let management decide when to start the CPU */ |
| runstate_set(RUN_STATE_PAUSED); |
| } |
| |
| trace_vmstate_downtime_checkpoint("dst-postcopy-bh-vm-started"); |
| } |
| |
| /* After all discards we can start running and asking for pages */ |
| static int loadvm_postcopy_handle_run(MigrationIncomingState *mis) |
| { |
| PostcopyState ps = postcopy_state_get(); |
| |
| trace_loadvm_postcopy_handle_run(); |
| if (ps != POSTCOPY_INCOMING_LISTENING) { |
| error_report("CMD_POSTCOPY_RUN in wrong postcopy state (%d)", ps); |
| return -1; |
| } |
| |
| postcopy_state_set(POSTCOPY_INCOMING_RUNNING); |
| migration_bh_schedule(loadvm_postcopy_handle_run_bh, mis); |
| |
| /* We need to finish reading the stream from the package |
| * and also stop reading anything more from the stream that loaded the |
| * package (since it's now being read by the listener thread). |
| * LOADVM_QUIT will quit all the layers of nested loadvm loops. |
| */ |
| return LOADVM_QUIT; |
| } |
| |
| /* We must be with page_request_mutex held */ |
| static gboolean postcopy_sync_page_req(gpointer key, gpointer value, |
| gpointer data) |
| { |
| MigrationIncomingState *mis = data; |
| void *host_addr = (void *) key; |
| ram_addr_t rb_offset; |
| RAMBlock *rb; |
| int ret; |
| |
| rb = qemu_ram_block_from_host(host_addr, true, &rb_offset); |
| if (!rb) { |
| /* |
| * This should _never_ happen. However be nice for a migrating VM to |
| * not crash/assert. Post an error (note: intended to not use *_once |
| * because we do want to see all the illegal addresses; and this can |
| * never be triggered by the guest so we're safe) and move on next. |
| */ |
| error_report("%s: illegal host addr %p", __func__, host_addr); |
| /* Try the next entry */ |
| return FALSE; |
| } |
| |
| ret = migrate_send_rp_message_req_pages(mis, rb, rb_offset); |
| if (ret) { |
| /* Please refer to above comment. */ |
| error_report("%s: send rp message failed for addr %p", |
| __func__, host_addr); |
| return FALSE; |
| } |
| |
| trace_postcopy_page_req_sync(host_addr); |
| |
| return FALSE; |
| } |
| |
| static void migrate_send_rp_req_pages_pending(MigrationIncomingState *mis) |
| { |
| WITH_QEMU_LOCK_GUARD(&mis->page_request_mutex) { |
| g_tree_foreach(mis->page_requested, postcopy_sync_page_req, mis); |
| } |
| } |
| |
| static int loadvm_postcopy_handle_resume(MigrationIncomingState *mis) |
| { |
| if (mis->state != MIGRATION_STATUS_POSTCOPY_RECOVER) { |
| error_report("%s: illegal resume received", __func__); |
| /* Don't fail the load, only for this. */ |
| return 0; |
| } |
| |
| /* |
| * Reset the last_rb before we resend any page req to source again, since |
| * the source should have it reset already. |
| */ |
| mis->last_rb = NULL; |
| |
| /* |
| * This means source VM is ready to resume the postcopy migration. |
| */ |
| migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_RECOVER, |
| MIGRATION_STATUS_POSTCOPY_ACTIVE); |
| |
| trace_loadvm_postcopy_handle_resume(); |
| |
| /* Tell source that "we are ready" */ |
| migrate_send_rp_resume_ack(mis, MIGRATION_RESUME_ACK_VALUE); |
| |
| /* |
| * After a postcopy recovery, the source should have lost the postcopy |
| * queue, or potentially the requested pages could have been lost during |
| * the network down phase. Let's re-sync with the source VM by re-sending |
| * all the pending pages that we eagerly need, so these threads won't get |
| * blocked too long due to the recovery. |
| * |
| * Without this procedure, the faulted destination VM threads (waiting for |
| * page requests right before the postcopy is interrupted) can keep hanging |
| * until the pages are sent by the source during the background copying of |
| * pages, or another thread faulted on the same address accidentally. |
| */ |
| migrate_send_rp_req_pages_pending(mis); |
| |
| /* |
| * It's time to switch state and release the fault thread to continue |
| * service page faults. Note that this should be explicitly after the |
| * above call to migrate_send_rp_req_pages_pending(). In short: |
| * migrate_send_rp_message_req_pages() is not thread safe, yet. |
| */ |
| qemu_sem_post(&mis->postcopy_pause_sem_fault); |
| |
| if (migrate_postcopy_preempt()) { |
| /* |
| * The preempt channel will be created in async manner, now let's |
| * wait for it and make sure it's created. |
| */ |
| qemu_sem_wait(&mis->postcopy_qemufile_dst_done); |
| assert(mis->postcopy_qemufile_dst); |
| /* Kick the fast ram load thread too */ |
| qemu_sem_post(&mis->postcopy_pause_sem_fast_load); |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * Immediately following this command is a blob of data containing an embedded |
| * chunk of migration stream; read it and load it. |
| * |
| * @mis: Incoming state |
| * @length: Length of packaged data to read |
| * |
| * Returns: Negative values on error |
| * |
| */ |
| static int loadvm_handle_cmd_packaged(MigrationIncomingState *mis) |
| { |
| int ret; |
| size_t length; |
| QIOChannelBuffer *bioc; |
| |
| length = qemu_get_be32(mis->from_src_file); |
| trace_loadvm_handle_cmd_packaged(length); |
| |
| if (length > MAX_VM_CMD_PACKAGED_SIZE) { |
| error_report("Unreasonably large packaged state: %zu", length); |
| return -1; |
| } |
| |
| bioc = qio_channel_buffer_new(length); |
| qio_channel_set_name(QIO_CHANNEL(bioc), "migration-loadvm-buffer"); |
| ret = qemu_get_buffer(mis->from_src_file, |
| bioc->data, |
| length); |
| if (ret != length) { |
| object_unref(OBJECT(bioc)); |
| error_report("CMD_PACKAGED: Buffer receive fail ret=%d length=%zu", |
| ret, length); |
| return (ret < 0) ? ret : -EAGAIN; |
| } |
| bioc->usage += length; |
| trace_loadvm_handle_cmd_packaged_received(ret); |
| |
| QEMUFile *packf = qemu_file_new_input(QIO_CHANNEL(bioc)); |
| |
| /* |
| * Before loading the guest states, ensure that the preempt channel has |
| * been ready to use, as some of the states (e.g. via virtio_load) might |
| * trigger page faults that will be handled through the preempt channel. |
| * So yield to the main thread in the case that the channel create event |
| * hasn't been dispatched. |
| * |
| * TODO: if we can move migration loadvm out of main thread, then we |
| * won't block main thread from polling the accept() fds. We can drop |
| * this as a whole when that is done. |
| */ |
| do { |
| if (!migrate_postcopy_preempt() || !qemu_in_coroutine() || |
| mis->postcopy_qemufile_dst) { |
| break; |
| } |
| |
| aio_co_schedule(qemu_get_current_aio_context(), qemu_coroutine_self()); |
| qemu_coroutine_yield(); |
| } while (1); |
| |
| ret = qemu_loadvm_state_main(packf, mis); |
| trace_loadvm_handle_cmd_packaged_main(ret); |
| qemu_fclose(packf); |
| object_unref(OBJECT(bioc)); |
| |
| return ret; |
| } |
| |
| /* |
| * Handle request that source requests for recved_bitmap on |
| * destination. Payload format: |
| * |
| * len (1 byte) + ramblock_name (<255 bytes) |
| */ |
| static int loadvm_handle_recv_bitmap(MigrationIncomingState *mis, |
| uint16_t len) |
| { |
| QEMUFile *file = mis->from_src_file; |
| RAMBlock *rb; |
| char block_name[256]; |
| size_t cnt; |
| |
| cnt = qemu_get_counted_string(file, block_name); |
| if (!cnt) { |
| error_report("%s: failed to read block name", __func__); |
| return -EINVAL; |
| } |
| |
| /* Validate before using the data */ |
| if (qemu_file_get_error(file)) { |
| return qemu_file_get_error(file); |
| } |
| |
| if (len != cnt + 1) { |
| error_report("%s: invalid payload length (%d)", __func__, len); |
| return -EINVAL; |
| } |
| |
| rb = qemu_ram_block_by_name(block_name); |
| if (!rb) { |
| error_report("%s: block '%s' not found", __func__, block_name); |
| return -EINVAL; |
| } |
| |
| migrate_send_rp_recv_bitmap(mis, block_name); |
| |
| trace_loadvm_handle_recv_bitmap(block_name); |
| |
| return 0; |
| } |
| |
| static int loadvm_process_enable_colo(MigrationIncomingState *mis) |
| { |
| int ret = migration_incoming_enable_colo(); |
| |
| if (!ret) { |
| ret = colo_init_ram_cache(); |
| if (ret) { |
| migration_incoming_disable_colo(); |
| } |
| } |
| return ret; |
| } |
| |
| /* |
| * Process an incoming 'QEMU_VM_COMMAND' |
| * 0 just a normal return |
| * LOADVM_QUIT All good, but exit the loop |
| * <0 Error |
| */ |
| static int loadvm_process_command(QEMUFile *f) |
| { |
| MigrationIncomingState *mis = migration_incoming_get_current(); |
| uint16_t cmd; |
| uint16_t len; |
| uint32_t tmp32; |
| |
| cmd = qemu_get_be16(f); |
| len = qemu_get_be16(f); |
| |
| /* Check validity before continue processing of cmds */ |
| if (qemu_file_get_error(f)) { |
| return qemu_file_get_error(f); |
| } |
| |
| if (cmd >= MIG_CMD_MAX || cmd == MIG_CMD_INVALID) { |
| error_report("MIG_CMD 0x%x unknown (len 0x%x)", cmd, len); |
| return -EINVAL; |
| } |
| |
| trace_loadvm_process_command(mig_cmd_args[cmd].name, len); |
| |
| if (mig_cmd_args[cmd].len != -1 && mig_cmd_args[cmd].len != len) { |
| error_report("%s received with bad length - expecting %zu, got %d", |
| mig_cmd_args[cmd].name, |
| (size_t)mig_cmd_args[cmd].len, len); |
| return -ERANGE; |
| } |
| |
| switch (cmd) { |
| case MIG_CMD_OPEN_RETURN_PATH: |
| if (mis->to_src_file) { |
| error_report("CMD_OPEN_RETURN_PATH called when RP already open"); |
| /* Not really a problem, so don't give up */ |
| return 0; |
| } |
| mis->to_src_file = qemu_file_get_return_path(f); |
| if (!mis->to_src_file) { |
| error_report("CMD_OPEN_RETURN_PATH failed"); |
| return -1; |
| } |
| |
| /* |
| * Switchover ack is enabled but no device uses it, so send an ACK to |
| * source that it's OK to switchover. Do it here, after return path has |
| * been created. |
| */ |
| if (migrate_switchover_ack() && !mis->switchover_ack_pending_num) { |
| int ret = migrate_send_rp_switchover_ack(mis); |
| if (ret) { |
| error_report( |
| "Could not send switchover ack RP MSG, err %d (%s)", ret, |
| strerror(-ret)); |
| return ret; |
| } |
| } |
| break; |
| |
| case MIG_CMD_PING: |
| tmp32 = qemu_get_be32(f); |
| trace_loadvm_process_command_ping(tmp32); |
| if (!mis->to_src_file) { |
| error_report("CMD_PING (0x%x) received with no return path", |
| tmp32); |
| return -1; |
| } |
| migrate_send_rp_pong(mis, tmp32); |
| break; |
| |
| case MIG_CMD_PACKAGED: |
| return loadvm_handle_cmd_packaged(mis); |
| |
| case MIG_CMD_POSTCOPY_ADVISE: |
| return loadvm_postcopy_handle_advise(mis, len); |
| |
| case MIG_CMD_POSTCOPY_LISTEN: |
| return loadvm_postcopy_handle_listen(mis); |
| |
| case MIG_CMD_POSTCOPY_RUN: |
| return loadvm_postcopy_handle_run(mis); |
| |
| case MIG_CMD_POSTCOPY_RAM_DISCARD: |
| return loadvm_postcopy_ram_handle_discard(mis, len); |
| |
| case MIG_CMD_POSTCOPY_RESUME: |
| return loadvm_postcopy_handle_resume(mis); |
| |
| case MIG_CMD_RECV_BITMAP: |
| return loadvm_handle_recv_bitmap(mis, len); |
| |
| case MIG_CMD_ENABLE_COLO: |
| return loadvm_process_enable_colo(mis); |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Read a footer off the wire and check that it matches the expected section |
| * |
| * Returns: true if the footer was good |
| * false if there is a problem (and calls error_report to say why) |
| */ |
| static bool check_section_footer(QEMUFile *f, SaveStateEntry *se) |
| { |
| int ret; |
| uint8_t read_mark; |
| uint32_t read_section_id; |
| |
| if (!migrate_get_current()->send_section_footer) { |
| /* No footer to check */ |
| return true; |
| } |
| |
| read_mark = qemu_get_byte(f); |
| |
| ret = qemu_file_get_error(f); |
| if (ret) { |
| error_report("%s: Read section footer failed: %d", |
| __func__, ret); |
| return false; |
| } |
| |
| if (read_mark != QEMU_VM_SECTION_FOOTER) { |
| error_report("Missing section footer for %s", se->idstr); |
| return false; |
| } |
| |
| read_section_id = qemu_get_be32(f); |
| if (read_section_id != se->load_section_id) { |
| error_report("Mismatched section id in footer for %s -" |
| " read 0x%x expected 0x%x", |
| se->idstr, read_section_id, se->load_section_id); |
| return false; |
| } |
| |
| /* All good */ |
| return true; |
| } |
| |
| static int |
| qemu_loadvm_section_start_full(QEMUFile *f, MigrationIncomingState *mis, |
| uint8_t type) |
| { |
| bool trace_downtime = (type == QEMU_VM_SECTION_FULL); |
| uint32_t instance_id, version_id, section_id; |
| int64_t start_ts, end_ts; |
| SaveStateEntry *se; |
| char idstr[256]; |
| int ret; |
| |
| /* Read section start */ |
| section_id = qemu_get_be32(f); |
| if (!qemu_get_counted_string(f, idstr)) { |
| error_report("Unable to read ID string for section %u", |
| section_id); |
| return -EINVAL; |
| } |
| instance_id = qemu_get_be32(f); |
| version_id = qemu_get_be32(f); |
| |
| ret = qemu_file_get_error(f); |
| if (ret) { |
| error_report("%s: Failed to read instance/version ID: %d", |
| __func__, ret); |
| return ret; |
| } |
| |
| trace_qemu_loadvm_state_section_startfull(section_id, idstr, |
| instance_id, version_id); |
| /* Find savevm section */ |
| se = find_se(idstr, instance_id); |
| if (se == NULL) { |
| error_report("Unknown savevm section or instance '%s' %"PRIu32". " |
| "Make sure that your current VM setup matches your " |
| "saved VM setup, including any hotplugged devices", |
| idstr, instance_id); |
| return -EINVAL; |
| } |
| |
| /* Validate version */ |
| if (version_id > se->version_id) { |
| error_report("savevm: unsupported version %d for '%s' v%d", |
| version_id, idstr, se->version_id); |
| return -EINVAL; |
| } |
| se->load_version_id = version_id; |
| se->load_section_id = section_id; |
| |
| /* Validate if it is a device's state */ |
| if (xen_enabled() && se->is_ram) { |
| error_report("loadvm: %s RAM loading not allowed on Xen", idstr); |
| return -EINVAL; |
| } |
| |
| if (trace_downtime) { |
| start_ts = qemu_clock_get_us(QEMU_CLOCK_REALTIME); |
| } |
| |
| ret = vmstate_load(f, se); |
| if (ret < 0) { |
| error_report("error while loading state for instance 0x%"PRIx32" of" |
| " device '%s'", instance_id, idstr); |
| return ret; |
| } |
| |
| if (trace_downtime) { |
| end_ts = qemu_clock_get_us(QEMU_CLOCK_REALTIME); |
| trace_vmstate_downtime_load("non-iterable", se->idstr, |
| se->instance_id, end_ts - start_ts); |
| } |
| |
| if (!check_section_footer(f, se)) { |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| static int |
| qemu_loadvm_section_part_end(QEMUFile *f, MigrationIncomingState *mis, |
| uint8_t type) |
| { |
| bool trace_downtime = (type == QEMU_VM_SECTION_END); |
| int64_t start_ts, end_ts; |
| uint32_t section_id; |
| SaveStateEntry *se; |
| int ret; |
| |
| section_id = qemu_get_be32(f); |
| |
| ret = qemu_file_get_error(f); |
| if (ret) { |
| error_report("%s: Failed to read section ID: %d", |
| __func__, ret); |
| return ret; |
| } |
| |
| trace_qemu_loadvm_state_section_partend(section_id); |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (se->load_section_id == section_id) { |
| break; |
| } |
| } |
| if (se == NULL) { |
| error_report("Unknown savevm section %d", section_id); |
| return -EINVAL; |
| } |
| |
| if (trace_downtime) { |
| start_ts = qemu_clock_get_us(QEMU_CLOCK_REALTIME); |
| } |
| |
| ret = vmstate_load(f, se); |
| if (ret < 0) { |
| error_report("error while loading state section id %d(%s)", |
| section_id, se->idstr); |
| return ret; |
| } |
| |
| if (trace_downtime) { |
| end_ts = qemu_clock_get_us(QEMU_CLOCK_REALTIME); |
| trace_vmstate_downtime_load("iterable", se->idstr, |
| se->instance_id, end_ts - start_ts); |
| } |
| |
| if (!check_section_footer(f, se)) { |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| static int qemu_loadvm_state_header(QEMUFile *f) |
| { |
| unsigned int v; |
| int ret; |
| |
| v = qemu_get_be32(f); |
| if (v != QEMU_VM_FILE_MAGIC) { |
| error_report("Not a migration stream"); |
| return -EINVAL; |
| } |
| |
| v = qemu_get_be32(f); |
| if (v == QEMU_VM_FILE_VERSION_COMPAT) { |
| error_report("SaveVM v2 format is obsolete and don't work anymore"); |
| return -ENOTSUP; |
| } |
| if (v != QEMU_VM_FILE_VERSION) { |
| error_report("Unsupported migration stream version"); |
| return -ENOTSUP; |
| } |
| |
| if (migrate_get_current()->send_configuration) { |
| if (qemu_get_byte(f) != QEMU_VM_CONFIGURATION) { |
| error_report("Configuration section missing"); |
| qemu_loadvm_state_cleanup(); |
| return -EINVAL; |
| } |
| ret = vmstate_load_state(f, &vmstate_configuration, &savevm_state, 0); |
| |
| if (ret) { |
| qemu_loadvm_state_cleanup(); |
| return ret; |
| } |
| } |
| return 0; |
| } |
| |
| static void qemu_loadvm_state_switchover_ack_needed(MigrationIncomingState *mis) |
| { |
| SaveStateEntry *se; |
| |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (!se->ops || !se->ops->switchover_ack_needed) { |
| continue; |
| } |
| |
| if (se->ops->switchover_ack_needed(se->opaque)) { |
| mis->switchover_ack_pending_num++; |
| } |
| } |
| |
| trace_loadvm_state_switchover_ack_needed(mis->switchover_ack_pending_num); |
| } |
| |
| static int qemu_loadvm_state_setup(QEMUFile *f, Error **errp) |
| { |
| ERRP_GUARD(); |
| SaveStateEntry *se; |
| int ret; |
| |
| trace_loadvm_state_setup(); |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (!se->ops || !se->ops->load_setup) { |
| continue; |
| } |
| if (se->ops->is_active) { |
| if (!se->ops->is_active(se->opaque)) { |
| continue; |
| } |
| } |
| |
| ret = se->ops->load_setup(f, se->opaque, errp); |
| if (ret < 0) { |
| error_prepend(errp, "Load state of device %s failed: ", |
| se->idstr); |
| qemu_file_set_error(f, ret); |
| return ret; |
| } |
| } |
| return 0; |
| } |
| |
| void qemu_loadvm_state_cleanup(void) |
| { |
| SaveStateEntry *se; |
| |
| trace_loadvm_state_cleanup(); |
| QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { |
| if (se->ops && se->ops->load_cleanup) { |
| se->ops->load_cleanup(se->opaque); |
| } |
| } |
| } |
| |
| /* Return true if we should continue the migration, or false. */ |
| static bool postcopy_pause_incoming(MigrationIncomingState *mis) |
| { |
| int i; |
| |
| trace_postcopy_pause_incoming(); |
| |
| assert(migrate_postcopy_ram()); |
| |
| /* |
| * Unregister yank with either from/to src would work, since ioc behind it |
| * is the same |
| */ |
| migration_ioc_unregister_yank_from_file(mis->from_src_file); |
| |
| assert(mis->from_src_file); |
| qemu_file_shutdown(mis->from_src_file); |
| qemu_fclose(mis->from_src_file); |
| mis->from_src_file = NULL; |
| |
| assert(mis->to_src_file); |
| qemu_file_shutdown(mis->to_src_file); |
| qemu_mutex_lock(&mis->rp_mutex); |
| qemu_fclose(mis->to_src_file); |
| mis->to_src_file = NULL; |
| qemu_mutex_unlock(&mis->rp_mutex); |
| |
| /* |
| * NOTE: this must happen before reset the PostcopyTmpPages below, |
| * otherwise it's racy to reset those fields when the fast load thread |
| * can be accessing it in parallel. |
| */ |
| if (mis->postcopy_qemufile_dst) { |
| qemu_file_shutdown(mis->postcopy_qemufile_dst); |
| /* Take the mutex to make sure the fast ram load thread halted */ |
| qemu_mutex_lock(&mis->postcopy_prio_thread_mutex); |
| migration_ioc_unregister_yank_from_file(mis->postcopy_qemufile_dst); |
| qemu_fclose(mis->postcopy_qemufile_dst); |
| mis->postcopy_qemufile_dst = NULL; |
| qemu_mutex_unlock(&mis->postcopy_prio_thread_mutex); |
| } |
| |
| /* Current state can be either ACTIVE or RECOVER */ |
| migrate_set_state(&mis->state, mis->state, |
| MIGRATION_STATUS_POSTCOPY_PAUSED); |
| |
| /* Notify the fault thread for the invalidated file handle */ |
| postcopy_fault_thread_notify(mis); |
| |
| /* |
| * If network is interrupted, any temp page we received will be useless |
| * because we didn't mark them as "received" in receivedmap. After a |
| * proper recovery later (which will sync src dirty bitmap with receivedmap |
| * on dest) these cached small pages will be resent again. |
| */ |
| for (i = 0; i < mis->postcopy_channels; i++) { |
| postcopy_temp_page_reset(&mis->postcopy_tmp_pages[i]); |
| } |
| |
| error_report("Detected IO failure for postcopy. " |
| "Migration paused."); |
| |
| while (mis->state == MIGRATION_STATUS_POSTCOPY_PAUSED) { |
| qemu_sem_wait(&mis->postcopy_pause_sem_dst); |
| } |
| |
| trace_postcopy_pause_incoming_continued(); |
| |
| return true; |
| } |
| |
| int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis) |
| { |
| uint8_t section_type; |
| int ret = 0; |
| |
| retry: |
| while (true) { |
| section_type = qemu_get_byte(f); |
| |
| ret = qemu_file_get_error_obj_any(f, mis->postcopy_qemufile_dst, NULL); |
| if (ret) { |
| break; |
| } |
| |
| trace_qemu_loadvm_state_section(section_type); |
| switch (section_type) { |
| case QEMU_VM_SECTION_START: |
| case QEMU_VM_SECTION_FULL: |
| ret = qemu_loadvm_section_start_full(f, mis, section_type); |
| if (ret < 0) { |
| goto out; |
| } |
| break; |
| case QEMU_VM_SECTION_PART: |
| case QEMU_VM_SECTION_END: |
| ret = qemu_loadvm_section_part_end(f, mis, section_type); |
| if (ret < 0) { |
| goto out; |
| } |
| break; |
| case QEMU_VM_COMMAND: |
| ret = loadvm_process_command(f); |
| trace_qemu_loadvm_state_section_command(ret); |
| if ((ret < 0) || (ret == LOADVM_QUIT)) { |
| goto out; |
| } |
| break; |
| case QEMU_VM_EOF: |
| /* This is the end of migration */ |
| goto out; |
| default: |
| error_report("Unknown savevm section type %d", section_type); |
| ret = -EINVAL; |
| goto out; |
| } |
| } |
| |
| out: |
| if (ret < 0) { |
| qemu_file_set_error(f, ret); |
| |
| /* Cancel bitmaps incoming regardless of recovery */ |
| dirty_bitmap_mig_cancel_incoming(); |
| |
| /* |
| * If we are during an active postcopy, then we pause instead |
| * of bail out to at least keep the VM's dirty data. Note |
| * that POSTCOPY_INCOMING_LISTENING stage is still not enough, |
| * during which we're still receiving device states and we |
| * still haven't yet started the VM on destination. |
| * |
| * Only RAM postcopy supports recovery. Still, if RAM postcopy is |
| * enabled, canceled bitmaps postcopy will not affect RAM postcopy |
| * recovering. |
| */ |
| if (postcopy_state_get() == POSTCOPY_INCOMING_RUNNING && |
| migrate_postcopy_ram() && postcopy_pause_incoming(mis)) { |
| /* Reset f to point to the newly created channel */ |
| f = mis->from_src_file; |
| goto retry; |
| } |
| } |
| return ret; |
| } |
| |
| int qemu_loadvm_state(QEMUFile *f) |
| { |
| MigrationIncomingState *mis = migration_incoming_get_current(); |
| Error *local_err = NULL; |
| int ret; |
| |
| if (qemu_savevm_state_blocked(&local_err)) { |
| error_report_err(local_err); |
| return -EINVAL; |
| } |
| |
| ret = qemu_loadvm_state_header(f); |
| if (ret) { |
| return ret; |
| } |
| |
| if (qemu_loadvm_state_setup(f, &local_err) != 0) { |
| error_report_err(local_err); |
| return -EINVAL; |
| } |
| |
| if (migrate_switchover_ack()) { |
| qemu_loadvm_state_switchover_ack_needed(mis); |
| } |
| |
| cpu_synchronize_all_pre_loadvm(); |
| |
| ret = qemu_loadvm_state_main(f, mis); |
| qemu_event_set(&mis->main_thread_load_event); |
| |
| trace_qemu_loadvm_state_post_main(ret); |
| |
| if (mis->have_listen_thread) { |
| /* Listen thread still going, can't clean up yet */ |
| return ret; |
| } |
| |
| if (ret == 0) { |
| ret = qemu_file_get_error(f); |
| } |
| |
| /* |
| * Try to read in the VMDESC section as well, so that dumping tools that |
| * intercept our migration stream have the chance to see it. |
| */ |
| |
| /* We've got to be careful; if we don't read the data and just shut the fd |
| * then the sender can error if we close while it's still sending. |
| * We also mustn't read data that isn't there; some transports (RDMA) |
| * will stall waiting for that data when the source has already closed. |
| */ |
| if (ret == 0 && should_send_vmdesc()) { |
| uint8_t *buf; |
| uint32_t size; |
| uint8_t section_type = qemu_get_byte(f); |
| |
| if (section_type != QEMU_VM_VMDESCRIPTION) { |
| error_report("Expected vmdescription section, but got %d", |
| section_type); |
| /* |
| * It doesn't seem worth failing at this point since |
| * we apparently have an otherwise valid VM state |
| */ |
| } else { |
| buf = g_malloc(0x1000); |
| size = qemu_get_be32(f); |
| |
| while (size > 0) { |
| uint32_t read_chunk = MIN(size, 0x1000); |
| qemu_get_buffer(f, buf, read_chunk); |
| size -= read_chunk; |
| } |
| g_free(buf); |
| } |
| } |
| |
| qemu_loadvm_state_cleanup(); |
| cpu_synchronize_all_post_init(); |
| |
| return ret; |
| } |
| |
| int qemu_load_device_state(QEMUFile *f) |
| { |
| MigrationIncomingState *mis = migration_incoming_get_current(); |
| int ret; |
| |
| /* Load QEMU_VM_SECTION_FULL section */ |
| ret = qemu_loadvm_state_main(f, mis); |
| if (ret < 0) { |
| error_report("Failed to load device state: %d", ret); |
| return ret; |
| } |
| |
| cpu_synchronize_all_post_init(); |
| return 0; |
| } |
| |
| int qemu_loadvm_approve_switchover(void) |
| { |
| MigrationIncomingState *mis = migration_incoming_get_current(); |
| |
| if (!mis->switchover_ack_pending_num) { |
| return -EINVAL; |
| } |
| |
| mis->switchover_ack_pending_num--; |
| trace_loadvm_approve_switchover(mis->switchover_ack_pending_num); |
| |
| if (mis->switchover_ack_pending_num) { |
| return 0; |
| } |
| |
| return migrate_send_rp_switchover_ack(mis); |
| } |
| |
| bool save_snapshot(const char *name, bool overwrite, const char *vmstate, |
| bool has_devices, strList *devices, Error **errp) |
| { |
| BlockDriverState *bs; |
| QEMUSnapshotInfo sn1, *sn = &sn1; |
| int ret = -1, ret2; |
| QEMUFile *f; |
| RunState saved_state = runstate_get(); |
| uint64_t vm_state_size; |
| g_autoptr(GDateTime) now = g_date_time_new_now_local(); |
| |
| GLOBAL_STATE_CODE(); |
| |
| if (migration_is_blocked(errp)) { |
| return false; |
| } |
| |
| if (!replay_can_snapshot()) { |
| error_setg(errp, "Record/replay does not allow making snapshot " |
| "right now. Try once more later."); |
| return false; |
| } |
| |
| if (!bdrv_all_can_snapshot(has_devices, devices, errp)) { |
| return false; |
| } |
| |
| /* Delete old snapshots of the same name */ |
| if (name) { |
| if (overwrite) { |
| if (bdrv_all_delete_snapshot(name, has_devices, |
| devices, errp) < 0) { |
| return false; |
| } |
| } else { |
| ret2 = bdrv_all_has_snapshot(name, has_devices, devices, errp); |
| if (ret2 < 0) { |
| return false; |
| } |
| if (ret2 == 1) { |
| error_setg(errp, |
| "Snapshot '%s' already exists in one or more devices", |
| name); |
| return false; |
| } |
| } |
| } |
| |
| bs = bdrv_all_find_vmstate_bs(vmstate, has_devices, devices, errp); |
| if (bs == NULL) { |
| return false; |
| } |
| |
| global_state_store(); |
| vm_stop(RUN_STATE_SAVE_VM); |
| |
| bdrv_drain_all_begin(); |
| |
| memset(sn, 0, sizeof(*sn)); |
| |
| /* fill auxiliary fields */ |
| sn->date_sec = g_date_time_to_unix(now); |
| sn->date_nsec = g_date_time_get_microsecond(now) * 1000; |
| sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); |
| if (replay_mode != REPLAY_MODE_NONE) { |
| sn->icount = replay_get_current_icount(); |
| } else { |
| sn->icount = -1ULL; |
| } |
| |
| if (name) { |
| pstrcpy(sn->name, sizeof(sn->name), name); |
| } else { |
| g_autofree char *autoname = g_date_time_format(now, "vm-%Y%m%d%H%M%S"); |
| pstrcpy(sn->name, sizeof(sn->name), autoname); |
| } |
| |
| /* save the VM state */ |
| f = qemu_fopen_bdrv(bs, 1); |
| if (!f) { |
| error_setg(errp, "Could not open VM state file"); |
| goto the_end; |
| } |
| ret = qemu_savevm_state(f, errp); |
| vm_state_size = qemu_file_transferred(f); |
| ret2 = qemu_fclose(f); |
| if (ret < 0) { |
| goto the_end; |
| } |
| if (ret2 < 0) { |
| ret = ret2; |
| goto the_end; |
| } |
| |
| ret = bdrv_all_create_snapshot(sn, bs, vm_state_size, |
| has_devices, devices, errp); |
| if (ret < 0) { |
| bdrv_all_delete_snapshot(sn->name, has_devices, devices, NULL); |
| goto the_end; |
| } |
| |
| ret = 0; |
| |
| the_end: |
| bdrv_drain_all_end(); |
| |
| vm_resume(saved_state); |
| return ret == 0; |
| } |
| |
| void qmp_xen_save_devices_state(const char *filename, bool has_live, bool live, |
| Error **errp) |
| { |
| QEMUFile *f; |
| QIOChannelFile *ioc; |
| int saved_vm_running; |
| int ret; |
| |
| if (!has_live) { |
| /* live default to true so old version of Xen tool stack can have a |
| * successful live migration */ |
| live = true; |
| } |
| |
| saved_vm_running = runstate_is_running(); |
| vm_stop(RUN_STATE_SAVE_VM); |
| global_state_store_running(); |
| |
| ioc = qio_channel_file_new_path(filename, O_WRONLY | O_CREAT | O_TRUNC, |
| 0660, errp); |
| if (!ioc) { |
| goto the_end; |
| } |
| qio_channel_set_name(QIO_CHANNEL(ioc), "migration-xen-save-state"); |
| f = qemu_file_new_output(QIO_CHANNEL(ioc)); |
| object_unref(OBJECT(ioc)); |
| ret = qemu_save_device_state(f); |
| if (ret < 0 || qemu_fclose(f) < 0) { |
| error_setg(errp, "saving Xen device state failed"); |
| } else { |
| /* libxl calls the QMP command "stop" before calling |
| * "xen-save-devices-state" and in case of migration failure, libxl |
| * would call "cont". |
| * So call bdrv_inactivate_all (release locks) here to let the other |
| * side of the migration take control of the images. |
| */ |
| if (live && !saved_vm_running) { |
| ret = bdrv_inactivate_all(); |
| if (ret) { |
| error_setg(errp, "%s: bdrv_inactivate_all() failed (%d)", |
| __func__, ret); |
| } |
| } |
| } |
| |
| the_end: |
| if (saved_vm_running) { |
| vm_start(); |
| } |
| } |
| |
| void qmp_xen_load_devices_state(const char *filename, Error **errp) |
| { |
| QEMUFile *f; |
| QIOChannelFile *ioc; |
| int ret; |
| |
| /* Guest must be paused before loading the device state; the RAM state |
| * will already have been loaded by xc |
| */ |
| if (runstate_is_running()) { |
| error_setg(errp, "Cannot update device state while vm is running"); |
| return; |
| } |
| vm_stop(RUN_STATE_RESTORE_VM); |
| |
| ioc = qio_channel_file_new_path(filename, O_RDONLY | O_BINARY, 0, errp); |
| if (!ioc) { |
| return; |
| } |
| qio_channel_set_name(QIO_CHANNEL(ioc), "migration-xen-load-state"); |
| f = qemu_file_new_input(QIO_CHANNEL(ioc)); |
| object_unref(OBJECT(ioc)); |
| |
| ret = qemu_loadvm_state(f); |
| qemu_fclose(f); |
| if (ret < 0) { |
| error_setg(errp, "loading Xen device state failed"); |
| } |
| migration_incoming_state_destroy(); |
| } |
| |
| bool load_snapshot(const char *name, const char *vmstate, |
| bool has_devices, strList *devices, Error **errp) |
| { |
| BlockDriverState *bs_vm_state; |
| QEMUSnapshotInfo sn; |
| QEMUFile *f; |
| int ret; |
| MigrationIncomingState *mis = migration_incoming_get_current(); |
| |
| if (!bdrv_all_can_snapshot(has_devices, devices, errp)) { |
| return false; |
| } |
| ret = bdrv_all_has_snapshot(name, has_devices, devices, errp); |
| if (ret < 0) { |
| return false; |
| } |
| if (ret == 0) { |
| error_setg(errp, "Snapshot '%s' does not exist in one or more devices", |
| name); |
| return false; |
| } |
| |
| bs_vm_state = bdrv_all_find_vmstate_bs(vmstate, has_devices, devices, errp); |
| if (!bs_vm_state) { |
| return false; |
| } |
| |
| /* Don't even try to load empty VM states */ |
| ret = bdrv_snapshot_find(bs_vm_state, &sn, name); |
| if (ret < 0) { |
| return false; |
| } else if (sn.vm_state_size == 0) { |
| error_setg(errp, "This is a disk-only snapshot. Revert to it " |
| " offline using qemu-img"); |
| return false; |
| } |
| |
| /* |
| * Flush the record/replay queue. Now the VM state is going |
| * to change. Therefore we don't need to preserve its consistency |
| */ |
| replay_flush_events(); |
| |
| /* Flush all IO requests so they don't interfere with the new state. */ |
| bdrv_drain_all_begin(); |
| |
| ret = bdrv_all_goto_snapshot(name, has_devices, devices, errp); |
| if (ret < 0) { |
| goto err_drain; |
| } |
| |
| /* restore the VM state */ |
| f = qemu_fopen_bdrv(bs_vm_state, 0); |
| if (!f) { |
| error_setg(errp, "Could not open VM state file"); |
| goto err_drain; |
| } |
| |
| qemu_system_reset(SHUTDOWN_CAUSE_SNAPSHOT_LOAD); |
| mis->from_src_file = f; |
| |
| if (!yank_register_instance(MIGRATION_YANK_INSTANCE, errp)) { |
| ret = -EINVAL; |
| goto err_drain; |
| } |
| ret = qemu_loadvm_state(f); |
| migration_incoming_state_destroy(); |
| |
| bdrv_drain_all_end(); |
| |
| if (ret < 0) { |
| error_setg(errp, "Error %d while loading VM state", ret); |
| return false; |
| } |
| |
| return true; |
| |
| err_drain: |
| bdrv_drain_all_end(); |
| return false; |
| } |
| |
| void load_snapshot_resume(RunState state) |
| { |
| vm_resume(state); |
| if (state == RUN_STATE_RUNNING && runstate_get() == RUN_STATE_SUSPENDED) { |
| qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER, &error_abort); |
| } |
| } |
| |
| bool delete_snapshot(const char *name, bool has_devices, |
| strList *devices, Error **errp) |
| { |
| if (!bdrv_all_can_snapshot(has_devices, devices, errp)) { |
| return false; |
| } |
| |
| if (bdrv_all_delete_snapshot(name, has_devices, devices, errp) < 0) { |
| return false; |
| } |
| |
| return true; |
| } |
| |
| void vmstate_register_ram(MemoryRegion *mr, DeviceState *dev) |
| { |
| qemu_ram_set_idstr(mr->ram_block, |
| memory_region_name(mr), dev); |
| qemu_ram_set_migratable(mr->ram_block); |
| } |
| |
| void vmstate_unregister_ram(MemoryRegion *mr, DeviceState *dev) |
| { |
| qemu_ram_unset_idstr(mr->ram_block); |
| qemu_ram_unset_migratable(mr->ram_block); |
| } |
| |
| void vmstate_register_ram_global(MemoryRegion *mr) |
| { |
| vmstate_register_ram(mr, NULL); |
| } |
| |
| bool vmstate_check_only_migratable(const VMStateDescription *vmsd) |
| { |
| /* check needed if --only-migratable is specified */ |
| if (!only_migratable) { |
| return true; |
| } |
| |
| return !(vmsd && vmsd->unmigratable); |
| } |
| |
| typedef struct SnapshotJob { |
| Job common; |
| char *tag; |
| char *vmstate; |
| strList *devices; |
| Coroutine *co; |
| Error **errp; |
| bool ret; |
| } SnapshotJob; |
| |
| static void qmp_snapshot_job_free(SnapshotJob *s) |
| { |
| g_free(s->tag); |
| g_free(s->vmstate); |
| qapi_free_strList(s->devices); |
| } |
| |
| |
| static void snapshot_load_job_bh(void *opaque) |
| { |
| Job *job = opaque; |
| SnapshotJob *s = container_of(job, SnapshotJob, common); |
| RunState orig_state = runstate_get(); |
| |
| job_progress_set_remaining(&s->common, 1); |
| |
| vm_stop(RUN_STATE_RESTORE_VM); |
| |
| s->ret = load_snapshot(s->tag, s->vmstate, true, s->devices, s->errp); |
| if (s->ret) { |
| load_snapshot_resume(orig_state); |
| } |
| |
| job_progress_update(&s->common, 1); |
| |
| qmp_snapshot_job_free(s); |
| aio_co_wake(s->co); |
| } |
| |
| static void snapshot_save_job_bh(void *opaque) |
| { |
| Job *job = opaque; |
| SnapshotJob *s = container_of(job, SnapshotJob, common); |
| |
| job_progress_set_remaining(&s->common, 1); |
| s->ret = save_snapshot(s->tag, false, s->vmstate, |
| true, s->devices, s->errp); |
| job_progress_update(&s->common, 1); |
| |
| qmp_snapshot_job_free(s); |
| aio_co_wake(s->co); |
| } |
| |
| static void snapshot_delete_job_bh(void *opaque) |
| { |
| Job *job = opaque; |
| SnapshotJob *s = container_of(job, SnapshotJob, common); |
| |
| job_progress_set_remaining(&s->common, 1); |
| s->ret = delete_snapshot(s->tag, true, s->devices, s->errp); |
| job_progress_update(&s->common, 1); |
| |
| qmp_snapshot_job_free(s); |
| aio_co_wake(s->co); |
| } |
| |
| static int coroutine_fn snapshot_save_job_run(Job *job, Error **errp) |
| { |
| SnapshotJob *s = container_of(job, SnapshotJob, common); |
| s->errp = errp; |
| s->co = qemu_coroutine_self(); |
| aio_bh_schedule_oneshot(qemu_get_aio_context(), |
| snapshot_save_job_bh, job); |
| qemu_coroutine_yield(); |
| return s->ret ? 0 : -1; |
| } |
| |
| static int coroutine_fn snapshot_load_job_run(Job *job, Error **errp) |
| { |
| SnapshotJob *s = container_of(job, SnapshotJob, common); |
| s->errp = errp; |
| s->co = qemu_coroutine_self(); |
| aio_bh_schedule_oneshot(qemu_get_aio_context(), |
| snapshot_load_job_bh, job); |
| qemu_coroutine_yield(); |
| return s->ret ? 0 : -1; |
| } |
| |
| static int coroutine_fn snapshot_delete_job_run(Job *job, Error **errp) |
| { |
| SnapshotJob *s = container_of(job, SnapshotJob, common); |
| s->errp = errp; |
| s->co = qemu_coroutine_self(); |
| aio_bh_schedule_oneshot(qemu_get_aio_context(), |
| snapshot_delete_job_bh, job); |
| qemu_coroutine_yield(); |
| return s->ret ? 0 : -1; |
| } |
| |
| |
| static const JobDriver snapshot_load_job_driver = { |
| .instance_size = sizeof(SnapshotJob), |
| .job_type = JOB_TYPE_SNAPSHOT_LOAD, |
| .run = snapshot_load_job_run, |
| }; |
| |
| static const JobDriver snapshot_save_job_driver = { |
| .instance_size = sizeof(SnapshotJob), |
| .job_type = JOB_TYPE_SNAPSHOT_SAVE, |
| .run = snapshot_save_job_run, |
| }; |
| |
| static const JobDriver snapshot_delete_job_driver = { |
| .instance_size = sizeof(SnapshotJob), |
| .job_type = JOB_TYPE_SNAPSHOT_DELETE, |
| .run = snapshot_delete_job_run, |
| }; |
| |
| |
| void qmp_snapshot_save(const char *job_id, |
| const char *tag, |
| const char *vmstate, |
| strList *devices, |
| Error **errp) |
| { |
| SnapshotJob *s; |
| |
| s = job_create(job_id, &snapshot_save_job_driver, NULL, |
| qemu_get_aio_context(), JOB_MANUAL_DISMISS, |
| NULL, NULL, errp); |
| if (!s) { |
| return; |
| } |
| |
| s->tag = g_strdup(tag); |
| s->vmstate = g_strdup(vmstate); |
| s->devices = QAPI_CLONE(strList, devices); |
| |
| job_start(&s->common); |
| } |
| |
| void qmp_snapshot_load(const char *job_id, |
| const char *tag, |
| const char *vmstate, |
| strList *devices, |
| Error **errp) |
| { |
| SnapshotJob *s; |
| |
| s = job_create(job_id, &snapshot_load_job_driver, NULL, |
| qemu_get_aio_context(), JOB_MANUAL_DISMISS, |
| NULL, NULL, errp); |
| if (!s) { |
| return; |
| } |
| |
| s->tag = g_strdup(tag); |
| s->vmstate = g_strdup(vmstate); |
| s->devices = QAPI_CLONE(strList, devices); |
| |
| job_start(&s->common); |
| } |
| |
| void qmp_snapshot_delete(const char *job_id, |
| const char *tag, |
| strList *devices, |
| Error **errp) |
| { |
| SnapshotJob *s; |
| |
| s = job_create(job_id, &snapshot_delete_job_driver, NULL, |
| qemu_get_aio_context(), JOB_MANUAL_DISMISS, |
| NULL, NULL, errp); |
| if (!s) { |
| return; |
| } |
| |
| s->tag = g_strdup(tag); |
| s->devices = QAPI_CLONE(strList, devices); |
| |
| job_start(&s->common); |
| } |