diff options
Diffstat (limited to 'src/migration/savevm.c')
| -rw-r--r-- | src/migration/savevm.c | 2195 |
1 files changed, 2195 insertions, 0 deletions
diff --git a/src/migration/savevm.c b/src/migration/savevm.c new file mode 100644 index 0000000..41be296 --- /dev/null +++ b/src/migration/savevm.c @@ -0,0 +1,2195 @@ +/* + * 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 "migration/postcopy-ram.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/bitops.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 + +const unsigned int postcopy_ram_discard_version = 0; + +static bool skip_section_footers; + +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 = 16, .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_PACKAGED] = { .len = 4, .name = "PACKAGED" }, + [MIG_CMD_MAX] = { .len = -1, .name = "MAX" }, +}; + +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 ssize_t block_put_buffer(void *opaque, const uint8_t *buf, + int64_t pos, size_t size) +{ + bdrv_save_vmstate(opaque, buf, pos, size); + return size; +} + +static ssize_t block_get_buffer(void *opaque, uint8_t *buf, int64_t pos, + size_t 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_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_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_new0(CompatEntry, 1); + 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_new0(SaveVMHandlers, 1); + 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); + 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_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 (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_new0(CompatEntry, 1); + 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); + 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); + } +} + +/** + * 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. + */ +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_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 QEMUSizedBuffer *qsb) +{ + size_t cur_iov; + size_t len = qsb_get_length(qsb); + uint32_t tmp; + + if (len > MAX_VM_CMD_PACKAGED_SIZE) { + error_report("%s: Unreasonably large packaged state: %zu", + __func__, len); + return -1; + } + + tmp = cpu_to_be32(len); + + trace_qemu_savevm_send_packaged(); + qemu_savevm_command_send(f, MIG_CMD_PACKAGED, 4, (uint8_t *)&tmp); + + /* all the data follows (concatinating the iov's) */ + for (cur_iov = 0; cur_iov < qsb->n_iov; cur_iov++) { + /* The iov entries are partially filled */ + size_t towrite = MIN(qsb->iov[cur_iov].iov_len, len); + len -= towrite; + + if (!towrite) { + break; + } + + qemu_put_buffer(f, qsb->iov[cur_iov].iov_base, towrite); + } + + return 0; +} + +/* Send prior to any postcopy transfer */ +void qemu_savevm_send_postcopy_advise(QEMUFile *f) +{ + uint64_t tmp[2]; + tmp[0] = cpu_to_be64(getpagesize()); + tmp[1] = cpu_to_be64(1ul << qemu_target_page_bits()); + + trace_qemu_savevm_send_postcopy_advise(); + qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_ADVISE, 16, (uint8_t *)tmp); +} + +/* 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++) { + cpu_to_be64w((uint64_t *)(buf + tmplen), start_list[t]); + tmplen += 8; + cpu_to_be64w((uint64_t *)(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); +} + +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; +} + +static bool enforce_config_section(void) +{ + MachineState *machine = MACHINE(qdev_get_machine()); + return machine->enforce_config_section; +} + +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); + + if (!savevm_state.skip_configuration || enforce_config_section()) { + qemu_put_byte(f, QEMU_VM_CONFIGURATION); + vmstate_save_state(f, &vmstate_configuration, &savevm_state, 0); + } + +} + +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); + } + + 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, bool postcopy) +{ + 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; + } + } + /* + * 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->save_live_complete_postcopy) { + 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()); + bool in_postcopy = migration_in_postcopy(migrate_get_current()); + 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 && 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); +} + +void qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only) +{ + QJSON *vmdesc; + int vmdesc_len; + SaveStateEntry *se; + int ret; + bool in_postcopy = migration_in_postcopy(migrate_get_current()); + + trace_savevm_state_complete_precopy(); + + cpu_synchronize_all_states(); + + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + if (!se->ops || + (in_postcopy && se->ops->save_live_complete_postcopy) || + (in_postcopy && !iterable_only) || + !se->ops->save_live_complete_precopy) { + 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_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; + } + } + + if (iterable_only) { + 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); + } + + if (!in_postcopy) { + /* Postcopy stream will still be going */ + 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); +} + +/* 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(QEMUFile *f, uint64_t max_size, + uint64_t *res_non_postcopiable, + uint64_t *res_postcopiable) +{ + SaveStateEntry *se; + + *res_non_postcopiable = 0; + *res_postcopiable = 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; + } + } + se->ops->save_live_pending(f, se->opaque, max_size, + res_non_postcopiable, res_postcopiable); + } +} + +void qemu_savevm_state_cleanup(void) +{ + SaveStateEntry *se; + + trace_savevm_state_cleanup(); + QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { + if (se->ops && se->ops->cleanup) { + se->ops->cleanup(se->opaque); + } + } +} + +static int qemu_savevm_state(QEMUFile *f, Error **errp) +{ + int ret; + MigrationParams params = { + .blk = 0, + .shared = 0 + }; + MigrationState *ms = migrate_init(¶ms); + ms->file = f; + + 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, false) > 0) { + break; + } + } + + ret = qemu_file_get_error(f); + if (ret == 0) { + qemu_savevm_state_complete_precopy(f, false); + ret = qemu_file_get_error(f); + } + qemu_savevm_state_cleanup(); + if (ret != 0) { + 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; +} + +enum LoadVMExitCodes { + /* Allow a command to quit all layers of nested loadvm loops */ + LOADVM_QUIT = 1, +}; + +static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis); + +/* ------ 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) +{ + PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_ADVISE); + uint64_t remote_hps, remote_tps; + + trace_loadvm_postcopy_handle_advise(); + if (ps != POSTCOPY_INCOMING_NONE) { + error_report("CMD_POSTCOPY_ADVISE in wrong postcopy state (%d)", ps); + return -1; + } + + if (!postcopy_ram_supported_by_host()) { + return -1; + } + + remote_hps = qemu_get_be64(mis->from_src_file); + if (remote_hps != getpagesize()) { + /* + * 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. + */ + error_report("Postcopy needs matching host page sizes (s=%d d=%d)", + (int)remote_hps, getpagesize()); + return -1; + } + + remote_tps = qemu_get_be64(mis->from_src_file); + if (remote_tps != (1ul << qemu_target_page_bits())) { + /* + * Again, some differences could be dealt with, but for now keep it + * simple. + */ + error_report("Postcopy needs matching target page sizes (s=%d d=%d)", + (int)remote_tps, 1 << qemu_target_page_bits()); + return -1; + } + + if (ram_postcopy_incoming_init(mis)) { + return -1; + } + + postcopy_state_set(POSTCOPY_INCOMING_ADVISE); + + 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(mis, 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) +{ + QEMUFile *f = opaque; + MigrationIncomingState *mis = migration_incoming_get_current(); + int load_res; + + qemu_sem_post(&mis->listen_thread_sem); + trace_postcopy_ram_listen_thread_start(); + + /* + * 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); + /* 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) { + error_report("%s: loadvm failed: %d", __func__, load_res); + qemu_file_set_error(f, load_res); + } else { + /* + * 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 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(); + + 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. + */ + exit(EXIT_FAILURE); + } + + 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); + trace_loadvm_postcopy_handle_listen(); + 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. + */ + postcopy_ram_prepare_discard(mis); + } + + /* + * 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 (postcopy_ram_enable_notify(mis)) { + return -1; + } + + if (mis->have_listen_thread) { + error_report("CMD_POSTCOPY_RAM_LISTEN already has a listen thread"); + return -1; + } + + mis->have_listen_thread = true; + /* Start up the listening thread and wait for it to signal ready */ + qemu_sem_init(&mis->listen_thread_sem, 0); + qemu_thread_create(&mis->listen_thread, "postcopy/listen", + postcopy_ram_listen_thread, mis->from_src_file, + QEMU_THREAD_JOINABLE); + qemu_sem_wait(&mis->listen_thread_sem); + qemu_sem_destroy(&mis->listen_thread_sem); + + return 0; +} + +/* After all discards we can start running and asking for pages */ +static int loadvm_postcopy_handle_run(MigrationIncomingState *mis) +{ + PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_RUNNING); + Error *local_err = NULL; + + trace_loadvm_postcopy_handle_run(); + if (ps != POSTCOPY_INCOMING_LISTENING) { + error_report("CMD_POSTCOPY_RUN in wrong postcopy state (%d)", ps); + return -1; + } + + /* TODO we should move all of this lot into postcopy_ram.c or a shared code + * in migration.c + */ + cpu_synchronize_all_post_init(); + + qemu_announce_self(); + + /* Make sure all file formats flush their mutable metadata */ + bdrv_invalidate_cache_all(&local_err); + if (local_err) { + error_report_err(local_err); + return -1; + } + + trace_loadvm_postcopy_handle_run_cpu_sync(); + cpu_synchronize_all_post_init(); + + trace_loadvm_postcopy_handle_run_vmstart(); + + 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); + } + + /* 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; +} + +/** + * 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; + uint8_t *buffer; + uint32_t length; + QEMUSizedBuffer *qsb; + + 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: %u", length); + return -1; + } + buffer = g_malloc0(length); + ret = qemu_get_buffer(mis->from_src_file, buffer, (int)length); + if (ret != length) { + g_free(buffer); + error_report("CMD_PACKAGED: Buffer receive fail ret=%d length=%d\n", + ret, length); + return (ret < 0) ? ret : -EAGAIN; + } + trace_loadvm_handle_cmd_packaged_received(ret); + + /* Setup a dummy QEMUFile that actually reads from the buffer */ + qsb = qsb_create(buffer, length); + g_free(buffer); /* Because qsb_create copies */ + if (!qsb) { + error_report("Unable to create qsb"); + } + QEMUFile *packf = qemu_bufopen("r", qsb); + + ret = qemu_loadvm_state_main(packf, mis); + trace_loadvm_handle_cmd_packaged_main(ret); + qemu_fclose(packf); + qsb_free(qsb); + + 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); + + trace_loadvm_process_command(cmd, len); + if (cmd >= MIG_CMD_MAX || cmd == MIG_CMD_INVALID) { + error_report("MIG_CMD 0x%x unknown (len 0x%x)", cmd, len); + return -EINVAL; + } + + 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; + } + 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); + + 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); + } + + return 0; +} + +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); + } +} + +static int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis) +{ + uint8_t section_type; + int 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); + 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; + } + + /* 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); + return ret; + } + if (!check_section_footer(f, le)) { + return -EINVAL; + } + 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); + return -EINVAL; + } + + 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); + return ret; + } + if (!check_section_footer(f, le)) { + return -EINVAL; + } + break; + case QEMU_VM_COMMAND: + ret = loadvm_process_command(f); + trace_qemu_loadvm_state_section_command(ret); + if ((ret < 0) || (ret & LOADVM_QUIT)) { + return ret; + } + break; + default: + error_report("Unknown savevm section type %d", section_type); + return -EINVAL; + } + } + + return 0; +} + +int qemu_loadvm_state(QEMUFile *f) +{ + MigrationIncomingState *mis = migration_incoming_get_current(); + Error *local_err = NULL; + unsigned int v; + int ret; + + 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 || enforce_config_section()) { + 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; + } + } + + 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); + } + } + + cpu_synchronize_all_post_init(); + + return ret; +} + +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; + AioContext *aio_context; + + if (!bdrv_all_can_snapshot(&bs)) { + monitor_printf(mon, "Device '%s' is writable but does not " + "support snapshots.\n", bdrv_get_device_name(bs)); + return; + } + + /* Delete old snapshots of the same name */ + if (name && bdrv_all_delete_snapshot(name, &bs1, &local_err) < 0) { + monitor_printf(mon, + "Error while deleting snapshot on device '%s': %s\n", + bdrv_get_device_name(bs1), error_get_pretty(local_err)); + error_free(local_err); + return; + } + + bs = bdrv_all_find_vmstate_bs(); + if (bs == NULL) { + monitor_printf(mon, "No block device can accept snapshots\n"); + return; + } + aio_context = bdrv_get_aio_context(bs); + + 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); + + aio_context_acquire(aio_context); + + 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); + } + + /* 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; + } + + ret = bdrv_all_create_snapshot(sn, bs, vm_state_size, &bs); + if (ret < 0) { + monitor_printf(mon, "Error while creating snapshot on '%s'\n", + bdrv_get_device_name(bs)); + } + + the_end: + aio_context_release(aio_context); + 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; + AioContext *aio_context; + + if (!bdrv_all_can_snapshot(&bs)) { + error_report("Device '%s' is writable but does not support snapshots.", + bdrv_get_device_name(bs)); + return -ENOTSUP; + } + ret = bdrv_all_find_snapshot(name, &bs); + if (ret < 0) { + error_report("Device '%s' does not have the requested snapshot '%s'", + bdrv_get_device_name(bs), name); + return ret; + } + + bs_vm_state = bdrv_all_find_vmstate_bs(); + if (!bs_vm_state) { + error_report("No block device supports snapshots"); + return -ENOTSUP; + } + aio_context = bdrv_get_aio_context(bs_vm_state); + + /* Don't even try to load empty VM states */ + aio_context_acquire(aio_context); + ret = bdrv_snapshot_find(bs_vm_state, &sn, name); + aio_context_release(aio_context); + 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; + } + + /* Flush all IO requests so they don't interfere with the new state. */ + bdrv_drain_all(); + + ret = bdrv_all_goto_snapshot(name, &bs); + 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); + + aio_context_acquire(aio_context); + ret = qemu_loadvm_state(f); + qemu_fclose(f); + aio_context_release(aio_context); + + 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 (bdrv_all_delete_snapshot(name, &bs, &err) < 0) { + 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; + int nb_sns, i; + int total; + int *available_snapshots; + AioContext *aio_context; + + bs = bdrv_all_find_vmstate_bs(); + if (!bs) { + monitor_printf(mon, "No available block device supports snapshots\n"); + return; + } + aio_context = bdrv_get_aio_context(bs); + + aio_context_acquire(aio_context); + nb_sns = bdrv_snapshot_list(bs, &sn_tab); + aio_context_release(aio_context); + + 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_new0(int, nb_sns); + total = 0; + for (i = 0; i < nb_sns; i++) { + if (bdrv_all_find_snapshot(sn_tab[i].id_str, &bs1) == 0) { + 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); +} |
