diff options
Diffstat (limited to 'qemu/migration/savevm.c')
| -rw-r--r-- | qemu/migration/savevm.c | 1605 |
1 files changed, 1605 insertions, 0 deletions
diff --git a/qemu/migration/savevm.c b/qemu/migration/savevm.c new file mode 100644 index 000000000..60712153f --- /dev/null +++ b/qemu/migration/savevm.c @@ -0,0 +1,1605 @@ +/* + * 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 "config-host.h" +#include "qemu-common.h" +#include "hw/boards.h" +#include "hw/hw.h" +#include "hw/qdev.h" +#include "net/net.h" +#include "monitor/monitor.h" +#include "sysemu/sysemu.h" +#include "qemu/timer.h" +#include "audio/audio.h" +#include "migration/migration.h" +#include "qapi/qmp/qerror.h" +#include "qemu/error-report.h" +#include "qemu/sockets.h" +#include "qemu/queue.h" +#include "sysemu/cpus.h" +#include "exec/memory.h" +#include "qmp-commands.h" +#include "trace.h" +#include "qemu/iov.h" +#include "block/snapshot.h" +#include "block/qapi.h" + + +#ifndef ETH_P_RARP +#define ETH_P_RARP 0x8035 +#endif +#define ARP_HTYPE_ETH 0x0001 +#define ARP_PTYPE_IP 0x0800 +#define ARP_OP_REQUEST_REV 0x3 + +static bool skip_section_footers; + +static int announce_self_create(uint8_t *buf, + uint8_t *mac_addr) +{ + /* Ethernet header. */ + memset(buf, 0xff, 6); /* destination MAC addr */ + memcpy(buf + 6, mac_addr, 6); /* source MAC addr */ + *(uint16_t *)(buf + 12) = htons(ETH_P_RARP); /* ethertype */ + + /* RARP header. */ + *(uint16_t *)(buf + 14) = htons(ARP_HTYPE_ETH); /* hardware addr space */ + *(uint16_t *)(buf + 16) = htons(ARP_PTYPE_IP); /* protocol addr space */ + *(buf + 18) = 6; /* hardware addr length (ethernet) */ + *(buf + 19) = 4; /* protocol addr length (IPv4) */ + *(uint16_t *)(buf + 20) = htons(ARP_OP_REQUEST_REV); /* opcode */ + memcpy(buf + 22, mac_addr, 6); /* source hw addr */ + memset(buf + 28, 0x00, 4); /* source protocol addr */ + memcpy(buf + 32, mac_addr, 6); /* target hw addr */ + memset(buf + 38, 0x00, 4); /* target protocol addr */ + + /* Padding to get up to 60 bytes (ethernet min packet size, minus FCS). */ + memset(buf + 42, 0x00, 18); + + return 60; /* len (FCS will be added by hardware) */ +} + +static void qemu_announce_self_iter(NICState *nic, void *opaque) +{ + uint8_t buf[60]; + int len; + + trace_qemu_announce_self_iter(qemu_ether_ntoa(&nic->conf->macaddr)); + len = announce_self_create(buf, nic->conf->macaddr.a); + + qemu_send_packet_raw(qemu_get_queue(nic), buf, len); +} + + +static void qemu_announce_self_once(void *opaque) +{ + static int count = SELF_ANNOUNCE_ROUNDS; + QEMUTimer *timer = *(QEMUTimer **)opaque; + + qemu_foreach_nic(qemu_announce_self_iter, NULL); + + if (--count) { + /* delay 50ms, 150ms, 250ms, ... */ + timer_mod(timer, qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + + self_announce_delay(count)); + } else { + timer_del(timer); + timer_free(timer); + } +} + +void qemu_announce_self(void) +{ + static QEMUTimer *timer; + timer = timer_new_ms(QEMU_CLOCK_REALTIME, qemu_announce_self_once, &timer); + qemu_announce_self_once(&timer); +} + +/***********************************************************/ +/* savevm/loadvm support */ + +static ssize_t block_writev_buffer(void *opaque, struct iovec *iov, int iovcnt, + int64_t pos) +{ + int ret; + QEMUIOVector qiov; + + qemu_iovec_init_external(&qiov, iov, iovcnt); + ret = bdrv_writev_vmstate(opaque, &qiov, pos); + if (ret < 0) { + return ret; + } + + return qiov.size; +} + +static int block_put_buffer(void *opaque, const uint8_t *buf, + int64_t pos, int size) +{ + bdrv_save_vmstate(opaque, buf, pos, size); + return size; +} + +static int block_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size) +{ + return bdrv_load_vmstate(opaque, buf, pos, size); +} + +static int bdrv_fclose(void *opaque) +{ + return bdrv_flush(opaque); +} + +static const QEMUFileOps bdrv_read_ops = { + .get_buffer = block_get_buffer, + .close = bdrv_fclose +}; + +static const QEMUFileOps bdrv_write_ops = { + .put_buffer = block_put_buffer, + .writev_buffer = block_writev_buffer, + .close = bdrv_fclose +}; + +static QEMUFile *qemu_fopen_bdrv(BlockDriverState *bs, int is_writable) +{ + if (is_writable) { + return qemu_fopen_ops(bs, &bdrv_write_ops); + } + return qemu_fopen_ops(bs, &bdrv_read_ops); +} + + +/* 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) +{ + QEMUTimer *v = pv; + timer_get(f, v); + return 0; +} + +static void put_timer(QEMUFile *f, void *pv, size_t size) +{ + QEMUTimer *v = pv; + timer_put(f, v); +} + +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]; + int instance_id; + int alias_id; + int version_id; + int section_id; + SaveVMHandlers *ops; + const VMStateDescription *vmsd; + void *opaque; + CompatEntry *compat; + int is_ram; +} SaveStateEntry; + +typedef struct SaveState { + QTAILQ_HEAD(, SaveStateEntry) handlers; + int global_section_id; + bool skip_configuration; + uint32_t len; + const char *name; +} SaveState; + +static SaveState savevm_state = { + .handlers = QTAILQ_HEAD_INITIALIZER(savevm_state.handlers), + .global_section_id = 0, + .skip_configuration = false, +}; + +void savevm_skip_configuration(void) +{ + savevm_state.skip_configuration = true; +} + + +static void configuration_pre_save(void *opaque) +{ + SaveState *state = opaque; + const char *current_name = MACHINE_GET_CLASS(current_machine)->name; + + state->len = strlen(current_name); + state->name = current_name; +} + +static int configuration_post_load(void *opaque, int version_id) +{ + SaveState *state = opaque; + const char *current_name = MACHINE_GET_CLASS(current_machine)->name; + + if (strncmp(state->name, current_name, state->len) != 0) { + error_report("Machine type received is '%s' and local is '%s'", + state->name, current_name); + return -EINVAL; + } + return 0; +} + +static const VMStateDescription vmstate_configuration = { + .name = "configuration", + .version_id = 1, + .post_load = configuration_post_load, + .pre_save = configuration_pre_save, + .fields = (VMStateField[]) { + VMSTATE_UINT32(len, SaveState), + VMSTATE_VBUFFER_ALLOC_UINT32(name, SaveState, 0, NULL, 0, len), + VMSTATE_END_OF_LIST() + }, +}; + +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"); + 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; + } + fprintf(out_file, "\n%*s]", indent, ""); + } + if (vmsd->subsections != NULL) { + const VMStateDescription **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); +} + +static int calculate_new_instance_id(const char *idstr) +{ + SaveStateEntry *se; + int 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; + } + } + 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; +} + +/* 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(DeviceState *dev, + const char *idstr, + int instance_id, + int version_id, + SaveVMHandlers *ops, + void *opaque) +{ + SaveStateEntry *se; + + se = g_malloc0(sizeof(SaveStateEntry)); + 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_live_setup != NULL) { + se->is_ram = 1; + } + + if (dev) { + char *id = qdev_get_dev_path(dev); + if (id) { + pstrcpy(se->idstr, sizeof(se->idstr), id); + pstrcat(se->idstr, sizeof(se->idstr), "/"); + g_free(id); + + se->compat = g_malloc0(sizeof(CompatEntry)); + pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), idstr); + se->compat->instance_id = instance_id == -1 ? + calculate_compat_instance_id(idstr) : instance_id; + instance_id = -1; + } + } + pstrcat(se->idstr, sizeof(se->idstr), idstr); + + if (instance_id == -1) { + se->instance_id = calculate_new_instance_id(se->idstr); + } else { + se->instance_id = instance_id; + } + assert(!se->compat || se->instance_id == 0); + /* add at the end of list */ + QTAILQ_INSERT_TAIL(&savevm_state.handlers, se, entry); + return 0; +} + +int register_savevm(DeviceState *dev, + const char *idstr, + int instance_id, + int version_id, + SaveStateHandler *save_state, + LoadStateHandler *load_state, + void *opaque) +{ + SaveVMHandlers *ops = g_malloc0(sizeof(SaveVMHandlers)); + ops->save_state = save_state; + ops->load_state = load_state; + return register_savevm_live(dev, idstr, instance_id, version_id, + ops, opaque); +} + +void unregister_savevm(DeviceState *dev, const char *idstr, void *opaque) +{ + SaveStateEntry *se, *new_se; + char id[256] = ""; + + if (dev) { + char *path = qdev_get_dev_path(dev); + if (path) { + pstrcpy(id, sizeof(id), path); + pstrcat(id, sizeof(id), "/"); + g_free(path); + } + } + pstrcat(id, sizeof(id), idstr); + + QTAILQ_FOREACH_SAFE(se, &savevm_state.handlers, entry, new_se) { + if (strcmp(se->idstr, id) == 0 && se->opaque == opaque) { + QTAILQ_REMOVE(&savevm_state.handlers, se, entry); + if (se->compat) { + g_free(se->compat); + } + g_free(se->ops); + g_free(se); + } + } +} + +int vmstate_register_with_alias_id(DeviceState *dev, int instance_id, + const VMStateDescription *vmsd, + void *opaque, int alias_id, + int required_for_version) +{ + 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_malloc0(sizeof(SaveStateEntry)); + 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 (dev) { + char *id = qdev_get_dev_path(dev); + if (id) { + pstrcpy(se->idstr, sizeof(se->idstr), id); + pstrcat(se->idstr, sizeof(se->idstr), "/"); + g_free(id); + + se->compat = g_malloc0(sizeof(CompatEntry)); + pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), vmsd->name); + se->compat->instance_id = instance_id == -1 ? + calculate_compat_instance_id(vmsd->name) : instance_id; + instance_id = -1; + } + } + pstrcat(se->idstr, sizeof(se->idstr), vmsd->name); + + if (instance_id == -1) { + se->instance_id = calculate_new_instance_id(se->idstr); + } else { + se->instance_id = instance_id; + } + assert(!se->compat || se->instance_id == 0); + /* add at the end of list */ + QTAILQ_INSERT_TAIL(&savevm_state.handlers, se, entry); + return 0; +} + +void vmstate_unregister(DeviceState *dev, 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) { + QTAILQ_REMOVE(&savevm_state.handlers, se, entry); + if (se->compat) { + g_free(se->compat); + } + g_free(se); + } + } +} + +static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id) +{ + trace_vmstate_load(se->idstr, se->vmsd ? se->vmsd->name : "(old)"); + if (!se->vmsd) { /* Old style */ + return se->ops->load_state(f, se->opaque, version_id); + } + return vmstate_load_state(f, se->vmsd, se->opaque, version_id); +} + +static void vmstate_save_old_style(QEMUFile *f, SaveStateEntry *se, QJSON *vmdesc) +{ + int64_t old_offset, size; + + old_offset = qemu_ftell_fast(f); + se->ops->save_state(f, se->opaque); + size = qemu_ftell_fast(f) - old_offset; + + if (vmdesc) { + json_prop_int(vmdesc, "size", size); + json_start_array(vmdesc, "fields"); + json_start_object(vmdesc, NULL); + json_prop_str(vmdesc, "name", "data"); + json_prop_int(vmdesc, "size", size); + json_prop_str(vmdesc, "type", "buffer"); + json_end_object(vmdesc); + json_end_array(vmdesc); + } +} + +static void vmstate_save(QEMUFile *f, SaveStateEntry *se, QJSON *vmdesc) +{ + trace_vmstate_save(se->idstr, se->vmsd ? se->vmsd->name : "(old)"); + if (!se->vmsd) { + vmstate_save_old_style(f, se, vmdesc); + return; + } + vmstate_save_state(f, se->vmsd, se->opaque, vmdesc); +} + +void savevm_skip_section_footers(void) +{ + skip_section_footers = true; +} + +/* + * 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 (!skip_section_footers) { + qemu_put_byte(f, QEMU_VM_SECTION_FOOTER); + qemu_put_be32(f, se->section_id); + } +} + +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_state_header(QEMUFile *f) +{ + trace_savevm_state_header(); + qemu_put_be32(f, QEMU_VM_FILE_MAGIC); + qemu_put_be32(f, QEMU_VM_FILE_VERSION); +} + +void qemu_savevm_state_begin(QEMUFile *f, + const MigrationParams *params) +{ + SaveStateEntry *se; + int ret; + + trace_savevm_state_begin(); + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + if (!se->ops || !se->ops->set_params) { + continue; + } + se->ops->set_params(params, se->opaque); + } + + if (!savevm_state.skip_configuration) { + qemu_put_byte(f, QEMU_VM_CONFIGURATION); + vmstate_save_state(f, &vmstate_configuration, &savevm_state, 0); + } + + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + if (!se->ops || !se->ops->save_live_setup) { + continue; + } + if (se->ops && 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_live_setup(f, se->opaque); + save_section_footer(f, se); + if (ret < 0) { + qemu_file_set_error(f, ret); + break; + } + } +} + +/* + * 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) +{ + SaveStateEntry *se; + int ret = 1; + + trace_savevm_state_iterate(); + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + if (!se->ops || !se->ops->save_live_iterate) { + continue; + } + if (se->ops && se->ops->is_active) { + if (!se->ops->is_active(se->opaque)) { + continue; + } + } + if (qemu_file_rate_limit(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) { + qemu_file_set_error(f, ret); + } + if (ret <= 0) { + /* Do not proceed to the next vmstate before this one reported + completion of the current stage. This serializes the migration + and reduces the probability that a faster changing state is + synchronized over and over again. */ + break; + } + } + return ret; +} + +static bool should_send_vmdesc(void) +{ + MachineState *machine = MACHINE(qdev_get_machine()); + return !machine->suppress_vmdesc; +} + +void qemu_savevm_state_complete(QEMUFile *f) +{ + QJSON *vmdesc; + int vmdesc_len; + SaveStateEntry *se; + int ret; + + trace_savevm_state_complete(); + + cpu_synchronize_all_states(); + + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + if (!se->ops || !se->ops->save_live_complete) { + continue; + } + if (se->ops && se->ops->is_active) { + if (!se->ops->is_active(se->opaque)) { + continue; + } + } + trace_savevm_section_start(se->idstr, se->section_id); + + save_section_header(f, se, QEMU_VM_SECTION_END); + + ret = se->ops->save_live_complete(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; + } + } + + vmdesc = qjson_new(); + json_prop_int(vmdesc, "page_size", TARGET_PAGE_SIZE); + json_start_array(vmdesc, "devices"); + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + + if ((!se->ops || !se->ops->save_state) && !se->vmsd) { + continue; + } + if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) { + trace_savevm_section_skip(se->idstr, se->section_id); + continue; + } + + trace_savevm_section_start(se->idstr, se->section_id); + + json_start_object(vmdesc, NULL); + json_prop_str(vmdesc, "name", se->idstr); + json_prop_int(vmdesc, "instance_id", se->instance_id); + + save_section_header(f, se, QEMU_VM_SECTION_FULL); + + vmstate_save(f, se, vmdesc); + + json_end_object(vmdesc); + trace_savevm_section_end(se->idstr, se->section_id, 0); + save_section_footer(f, se); + } + + qemu_put_byte(f, QEMU_VM_EOF); + + json_end_array(vmdesc); + qjson_finish(vmdesc); + vmdesc_len = strlen(qjson_get_str(vmdesc)); + + if (should_send_vmdesc()) { + qemu_put_byte(f, QEMU_VM_VMDESCRIPTION); + qemu_put_be32(f, vmdesc_len); + qemu_put_buffer(f, (uint8_t *)qjson_get_str(vmdesc), vmdesc_len); + } + object_unref(OBJECT(vmdesc)); + + qemu_fflush(f); +} + +uint64_t qemu_savevm_state_pending(QEMUFile *f, uint64_t max_size) +{ + SaveStateEntry *se; + uint64_t ret = 0; + + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + if (!se->ops || !se->ops->save_live_pending) { + continue; + } + if (se->ops && se->ops->is_active) { + if (!se->ops->is_active(se->opaque)) { + continue; + } + } + ret += se->ops->save_live_pending(f, se->opaque, max_size); + } + return ret; +} + +void qemu_savevm_state_cancel(void) +{ + SaveStateEntry *se; + + trace_savevm_state_cancel(); + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + if (se->ops && se->ops->cancel) { + se->ops->cancel(se->opaque); + } + } +} + +static int qemu_savevm_state(QEMUFile *f, Error **errp) +{ + int ret; + MigrationParams params = { + .blk = 0, + .shared = 0 + }; + + if (qemu_savevm_state_blocked(errp)) { + return -EINVAL; + } + + qemu_mutex_unlock_iothread(); + qemu_savevm_state_header(f); + qemu_savevm_state_begin(f, ¶ms); + qemu_mutex_lock_iothread(); + + while (qemu_file_get_error(f) == 0) { + if (qemu_savevm_state_iterate(f) > 0) { + break; + } + } + + ret = qemu_file_get_error(f); + if (ret == 0) { + qemu_savevm_state_complete(f); + ret = qemu_file_get_error(f); + } + if (ret != 0) { + qemu_savevm_state_cancel(); + error_setg_errno(errp, -ret, "Error while writing VM state"); + } + return ret; +} + +static int qemu_save_device_state(QEMUFile *f) +{ + SaveStateEntry *se; + + 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) { + if (se->is_ram) { + continue; + } + if ((!se->ops || !se->ops->save_state) && !se->vmsd) { + continue; + } + if (se->vmsd && !vmstate_save_needed(se->vmsd, se->opaque)) { + continue; + } + + save_section_header(f, se, QEMU_VM_SECTION_FULL); + + vmstate_save(f, se, NULL); + + save_section_footer(f, se); + } + + qemu_put_byte(f, QEMU_VM_EOF); + + return qemu_file_get_error(f); +} + +static SaveStateEntry *find_se(const char *idstr, int 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; +} + +struct LoadStateEntry { + QLIST_ENTRY(LoadStateEntry) entry; + SaveStateEntry *se; + int section_id; + int version_id; +}; + +/* + * 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, LoadStateEntry *le) +{ + uint8_t read_mark; + uint32_t read_section_id; + + if (skip_section_footers) { + /* No footer to check */ + return true; + } + + read_mark = qemu_get_byte(f); + + if (read_mark != QEMU_VM_SECTION_FOOTER) { + error_report("Missing section footer for %s", le->se->idstr); + return false; + } + + read_section_id = qemu_get_be32(f); + if (read_section_id != le->section_id) { + error_report("Mismatched section id in footer for %s -" + " read 0x%x expected 0x%x", + le->se->idstr, read_section_id, le->section_id); + return false; + } + + /* All good */ + return true; +} + +void loadvm_free_handlers(MigrationIncomingState *mis) +{ + LoadStateEntry *le, *new_le; + + QLIST_FOREACH_SAFE(le, &mis->loadvm_handlers, entry, new_le) { + QLIST_REMOVE(le, entry); + g_free(le); + } +} + +int qemu_loadvm_state(QEMUFile *f) +{ + MigrationIncomingState *mis = migration_incoming_get_current(); + Error *local_err = NULL; + uint8_t section_type; + unsigned int v; + int ret; + int file_error_after_eof = -1; + + if (qemu_savevm_state_blocked(&local_err)) { + error_report_err(local_err); + return -EINVAL; + } + + 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 (!savevm_state.skip_configuration) { + if (qemu_get_byte(f) != QEMU_VM_CONFIGURATION) { + error_report("Configuration section missing"); + return -EINVAL; + } + ret = vmstate_load_state(f, &vmstate_configuration, &savevm_state, 0); + + if (ret) { + return ret; + } + } + + while ((section_type = qemu_get_byte(f)) != QEMU_VM_EOF) { + uint32_t instance_id, version_id, section_id; + SaveStateEntry *se; + LoadStateEntry *le; + char idstr[256]; + + trace_qemu_loadvm_state_section(section_type); + switch (section_type) { + case QEMU_VM_SECTION_START: + case QEMU_VM_SECTION_FULL: + /* 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); + + 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' %d", + idstr, instance_id); + ret = -EINVAL; + goto out; + } + + /* Validate version */ + if (version_id > se->version_id) { + error_report("savevm: unsupported version %d for '%s' v%d", + version_id, idstr, se->version_id); + ret = -EINVAL; + goto out; + } + + /* Add entry */ + le = g_malloc0(sizeof(*le)); + + le->se = se; + le->section_id = section_id; + le->version_id = version_id; + QLIST_INSERT_HEAD(&mis->loadvm_handlers, le, entry); + + ret = vmstate_load(f, le->se, le->version_id); + if (ret < 0) { + error_report("error while loading state for instance 0x%x of" + " device '%s'", instance_id, idstr); + goto out; + } + if (!check_section_footer(f, le)) { + ret = -EINVAL; + goto out; + } + break; + case QEMU_VM_SECTION_PART: + case QEMU_VM_SECTION_END: + section_id = qemu_get_be32(f); + + trace_qemu_loadvm_state_section_partend(section_id); + QLIST_FOREACH(le, &mis->loadvm_handlers, entry) { + if (le->section_id == section_id) { + break; + } + } + if (le == NULL) { + error_report("Unknown savevm section %d", section_id); + ret = -EINVAL; + goto out; + } + + ret = vmstate_load(f, le->se, le->version_id); + if (ret < 0) { + error_report("error while loading state section id %d(%s)", + section_id, le->se->idstr); + goto out; + } + if (!check_section_footer(f, le)) { + ret = -EINVAL; + goto out; + } + break; + default: + error_report("Unknown savevm section type %d", section_type); + ret = -EINVAL; + goto out; + } + } + + file_error_after_eof = 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 (should_send_vmdesc()) { + uint8_t *buf; + uint32_t size; + 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); + } + } + + cpu_synchronize_all_post_init(); + + ret = 0; + +out: + if (ret == 0) { + /* We may not have a VMDESC section, so ignore relative errors */ + ret = file_error_after_eof; + } + + return ret; +} + +static BlockDriverState *find_vmstate_bs(void) +{ + BlockDriverState *bs = NULL; + while ((bs = bdrv_next(bs))) { + if (bdrv_can_snapshot(bs)) { + return bs; + } + } + return NULL; +} + +/* + * Deletes snapshots of a given name in all opened images. + */ +static int del_existing_snapshots(Monitor *mon, const char *name) +{ + BlockDriverState *bs; + QEMUSnapshotInfo sn1, *snapshot = &sn1; + Error *err = NULL; + + bs = NULL; + while ((bs = bdrv_next(bs))) { + if (bdrv_can_snapshot(bs) && + bdrv_snapshot_find(bs, snapshot, name) >= 0) { + bdrv_snapshot_delete_by_id_or_name(bs, name, &err); + if (err) { + monitor_printf(mon, + "Error while deleting snapshot on device '%s':" + " %s\n", + bdrv_get_device_name(bs), + error_get_pretty(err)); + error_free(err); + return -1; + } + } + } + + return 0; +} + +void hmp_savevm(Monitor *mon, const QDict *qdict) +{ + BlockDriverState *bs, *bs1; + QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1; + int ret; + QEMUFile *f; + int saved_vm_running; + uint64_t vm_state_size; + qemu_timeval tv; + struct tm tm; + const char *name = qdict_get_try_str(qdict, "name"); + Error *local_err = NULL; + + /* Verify if there is a device that doesn't support snapshots and is writable */ + bs = NULL; + while ((bs = bdrv_next(bs))) { + + if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) { + continue; + } + + if (!bdrv_can_snapshot(bs)) { + monitor_printf(mon, "Device '%s' is writable but does not support snapshots.\n", + bdrv_get_device_name(bs)); + return; + } + } + + bs = find_vmstate_bs(); + if (!bs) { + monitor_printf(mon, "No block device can accept snapshots\n"); + return; + } + + saved_vm_running = runstate_is_running(); + + ret = global_state_store(); + if (ret) { + monitor_printf(mon, "Error saving global state\n"); + return; + } + vm_stop(RUN_STATE_SAVE_VM); + + memset(sn, 0, sizeof(*sn)); + + /* fill auxiliary fields */ + qemu_gettimeofday(&tv); + sn->date_sec = tv.tv_sec; + sn->date_nsec = tv.tv_usec * 1000; + sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); + + if (name) { + ret = bdrv_snapshot_find(bs, old_sn, name); + if (ret >= 0) { + pstrcpy(sn->name, sizeof(sn->name), old_sn->name); + pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str); + } else { + pstrcpy(sn->name, sizeof(sn->name), name); + } + } else { + /* cast below needed for OpenBSD where tv_sec is still 'long' */ + localtime_r((const time_t *)&tv.tv_sec, &tm); + strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", &tm); + } + + /* Delete old snapshots of the same name */ + if (name && del_existing_snapshots(mon, name) < 0) { + goto the_end; + } + + /* save the VM state */ + f = qemu_fopen_bdrv(bs, 1); + if (!f) { + monitor_printf(mon, "Could not open VM state file\n"); + goto the_end; + } + ret = qemu_savevm_state(f, &local_err); + vm_state_size = qemu_ftell(f); + qemu_fclose(f); + if (ret < 0) { + monitor_printf(mon, "%s\n", error_get_pretty(local_err)); + error_free(local_err); + goto the_end; + } + + /* create the snapshots */ + + bs1 = NULL; + while ((bs1 = bdrv_next(bs1))) { + if (bdrv_can_snapshot(bs1)) { + /* Write VM state size only to the image that contains the state */ + sn->vm_state_size = (bs == bs1 ? vm_state_size : 0); + ret = bdrv_snapshot_create(bs1, sn); + if (ret < 0) { + monitor_printf(mon, "Error while creating snapshot on '%s'\n", + bdrv_get_device_name(bs1)); + } + } + } + + the_end: + if (saved_vm_running) { + vm_start(); + } +} + +void qmp_xen_save_devices_state(const char *filename, Error **errp) +{ + QEMUFile *f; + int saved_vm_running; + int ret; + + saved_vm_running = runstate_is_running(); + vm_stop(RUN_STATE_SAVE_VM); + global_state_store_running(); + + f = qemu_fopen(filename, "wb"); + if (!f) { + error_setg_file_open(errp, errno, filename); + goto the_end; + } + ret = qemu_save_device_state(f); + qemu_fclose(f); + if (ret < 0) { + error_setg(errp, QERR_IO_ERROR); + } + + the_end: + if (saved_vm_running) { + vm_start(); + } +} + +int load_vmstate(const char *name) +{ + BlockDriverState *bs, *bs_vm_state; + QEMUSnapshotInfo sn; + QEMUFile *f; + int ret; + + bs_vm_state = find_vmstate_bs(); + if (!bs_vm_state) { + error_report("No block device supports snapshots"); + return -ENOTSUP; + } + + /* Don't even try to load empty VM states */ + ret = bdrv_snapshot_find(bs_vm_state, &sn, name); + if (ret < 0) { + return ret; + } else if (sn.vm_state_size == 0) { + error_report("This is a disk-only snapshot. Revert to it offline " + "using qemu-img."); + return -EINVAL; + } + + /* Verify if there is any device that doesn't support snapshots and is + writable and check if the requested snapshot is available too. */ + bs = NULL; + while ((bs = bdrv_next(bs))) { + + if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) { + continue; + } + + if (!bdrv_can_snapshot(bs)) { + error_report("Device '%s' is writable but does not support snapshots.", + bdrv_get_device_name(bs)); + return -ENOTSUP; + } + + ret = bdrv_snapshot_find(bs, &sn, name); + if (ret < 0) { + error_report("Device '%s' does not have the requested snapshot '%s'", + bdrv_get_device_name(bs), name); + return ret; + } + } + + /* Flush all IO requests so they don't interfere with the new state. */ + bdrv_drain_all(); + + bs = NULL; + while ((bs = bdrv_next(bs))) { + if (bdrv_can_snapshot(bs)) { + ret = bdrv_snapshot_goto(bs, name); + if (ret < 0) { + error_report("Error %d while activating snapshot '%s' on '%s'", + ret, name, bdrv_get_device_name(bs)); + return ret; + } + } + } + + /* restore the VM state */ + f = qemu_fopen_bdrv(bs_vm_state, 0); + if (!f) { + error_report("Could not open VM state file"); + return -EINVAL; + } + + qemu_system_reset(VMRESET_SILENT); + migration_incoming_state_new(f); + ret = qemu_loadvm_state(f); + + qemu_fclose(f); + migration_incoming_state_destroy(); + if (ret < 0) { + error_report("Error %d while loading VM state", ret); + return ret; + } + + return 0; +} + +void hmp_delvm(Monitor *mon, const QDict *qdict) +{ + BlockDriverState *bs; + Error *err; + const char *name = qdict_get_str(qdict, "name"); + + if (!find_vmstate_bs()) { + monitor_printf(mon, "No block device supports snapshots\n"); + return; + } + + bs = NULL; + while ((bs = bdrv_next(bs))) { + if (bdrv_can_snapshot(bs)) { + err = NULL; + bdrv_snapshot_delete_by_id_or_name(bs, name, &err); + if (err) { + monitor_printf(mon, + "Error while deleting snapshot on device '%s':" + " %s\n", + bdrv_get_device_name(bs), + error_get_pretty(err)); + error_free(err); + } + } + } +} + +void hmp_info_snapshots(Monitor *mon, const QDict *qdict) +{ + BlockDriverState *bs, *bs1; + QEMUSnapshotInfo *sn_tab, *sn, s, *sn_info = &s; + int nb_sns, i, ret, available; + int total; + int *available_snapshots; + + bs = find_vmstate_bs(); + if (!bs) { + monitor_printf(mon, "No available block device supports snapshots\n"); + return; + } + + nb_sns = bdrv_snapshot_list(bs, &sn_tab); + if (nb_sns < 0) { + monitor_printf(mon, "bdrv_snapshot_list: error %d\n", nb_sns); + return; + } + + if (nb_sns == 0) { + monitor_printf(mon, "There is no snapshot available.\n"); + return; + } + + available_snapshots = g_malloc0(sizeof(int) * nb_sns); + total = 0; + for (i = 0; i < nb_sns; i++) { + sn = &sn_tab[i]; + available = 1; + bs1 = NULL; + + while ((bs1 = bdrv_next(bs1))) { + if (bdrv_can_snapshot(bs1) && bs1 != bs) { + ret = bdrv_snapshot_find(bs1, sn_info, sn->id_str); + if (ret < 0) { + available = 0; + break; + } + } + } + + if (available) { + available_snapshots[total] = i; + total++; + } + } + + if (total > 0) { + bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, NULL); + monitor_printf(mon, "\n"); + for (i = 0; i < total; i++) { + sn = &sn_tab[available_snapshots[i]]; + bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, sn); + monitor_printf(mon, "\n"); + } + } else { + monitor_printf(mon, "There is no suitable snapshot available\n"); + } + + g_free(sn_tab); + g_free(available_snapshots); + +} + +void vmstate_register_ram(MemoryRegion *mr, DeviceState *dev) +{ + qemu_ram_set_idstr(memory_region_get_ram_addr(mr) & TARGET_PAGE_MASK, + memory_region_name(mr), dev); +} + +void vmstate_unregister_ram(MemoryRegion *mr, DeviceState *dev) +{ + qemu_ram_unset_idstr(memory_region_get_ram_addr(mr) & TARGET_PAGE_MASK); +} + +void vmstate_register_ram_global(MemoryRegion *mr) +{ + vmstate_register_ram(mr, NULL); +} |