| /* |
| * QEMU live migration |
| * |
| * Copyright IBM, Corp. 2008 |
| * |
| * Authors: |
| * Anthony Liguori <aliguori@us.ibm.com> |
| * |
| * This work is licensed under the terms of the GNU GPL, version 2. See |
| * the COPYING file in the top-level directory. |
| * |
| */ |
| |
| #include "qemu-common.h" |
| #include "migration.h" |
| #include "monitor.h" |
| #include "buffered_file.h" |
| #include "sysemu.h" |
| #include "block.h" |
| #include "qemu_socket.h" |
| #include "block-migration.h" |
| #include "qmp-commands.h" |
| |
| //#define DEBUG_MIGRATION |
| |
| #ifdef DEBUG_MIGRATION |
| #define DPRINTF(fmt, ...) \ |
| do { printf("migration: " fmt, ## __VA_ARGS__); } while (0) |
| #else |
| #define DPRINTF(fmt, ...) \ |
| do { } while (0) |
| #endif |
| |
| enum { |
| MIG_STATE_ERROR, |
| MIG_STATE_SETUP, |
| MIG_STATE_CANCELLED, |
| MIG_STATE_ACTIVE, |
| MIG_STATE_COMPLETED, |
| }; |
| |
| #define MAX_THROTTLE (32 << 20) /* Migration speed throttling */ |
| |
| static NotifierList migration_state_notifiers = |
| NOTIFIER_LIST_INITIALIZER(migration_state_notifiers); |
| |
| /* When we add fault tolerance, we could have several |
| migrations at once. For now we don't need to add |
| dynamic creation of migration */ |
| |
| static MigrationState *migrate_get_current(void) |
| { |
| static MigrationState current_migration = { |
| .state = MIG_STATE_SETUP, |
| .bandwidth_limit = MAX_THROTTLE, |
| }; |
| |
| return ¤t_migration; |
| } |
| |
| int qemu_start_incoming_migration(const char *uri) |
| { |
| const char *p; |
| int ret; |
| |
| if (strstart(uri, "tcp:", &p)) |
| ret = tcp_start_incoming_migration(p); |
| #if !defined(WIN32) |
| else if (strstart(uri, "exec:", &p)) |
| ret = exec_start_incoming_migration(p); |
| else if (strstart(uri, "unix:", &p)) |
| ret = unix_start_incoming_migration(p); |
| else if (strstart(uri, "fd:", &p)) |
| ret = fd_start_incoming_migration(p); |
| #endif |
| else { |
| fprintf(stderr, "unknown migration protocol: %s\n", uri); |
| ret = -EPROTONOSUPPORT; |
| } |
| return ret; |
| } |
| |
| void process_incoming_migration(QEMUFile *f) |
| { |
| if (qemu_loadvm_state(f) < 0) { |
| fprintf(stderr, "load of migration failed\n"); |
| exit(0); |
| } |
| qemu_announce_self(); |
| DPRINTF("successfully loaded vm state\n"); |
| |
| if (autostart) { |
| vm_start(); |
| } else { |
| runstate_set(RUN_STATE_PRELAUNCH); |
| } |
| } |
| |
| /* amount of nanoseconds we are willing to wait for migration to be down. |
| * the choice of nanoseconds is because it is the maximum resolution that |
| * get_clock() can achieve. It is an internal measure. All user-visible |
| * units must be in seconds */ |
| static uint64_t max_downtime = 30000000; |
| |
| uint64_t migrate_max_downtime(void) |
| { |
| return max_downtime; |
| } |
| |
| MigrationInfo *qmp_query_migrate(Error **errp) |
| { |
| MigrationInfo *info = g_malloc0(sizeof(*info)); |
| MigrationState *s = migrate_get_current(); |
| |
| switch (s->state) { |
| case MIG_STATE_SETUP: |
| /* no migration has happened ever */ |
| break; |
| case MIG_STATE_ACTIVE: |
| info->has_status = true; |
| info->status = g_strdup("active"); |
| |
| info->has_ram = true; |
| info->ram = g_malloc0(sizeof(*info->ram)); |
| info->ram->transferred = ram_bytes_transferred(); |
| info->ram->remaining = ram_bytes_remaining(); |
| info->ram->total = ram_bytes_total(); |
| |
| if (blk_mig_active()) { |
| info->has_disk = true; |
| info->disk = g_malloc0(sizeof(*info->disk)); |
| info->disk->transferred = blk_mig_bytes_transferred(); |
| info->disk->remaining = blk_mig_bytes_remaining(); |
| info->disk->total = blk_mig_bytes_total(); |
| } |
| break; |
| case MIG_STATE_COMPLETED: |
| info->has_status = true; |
| info->status = g_strdup("completed"); |
| break; |
| case MIG_STATE_ERROR: |
| info->has_status = true; |
| info->status = g_strdup("failed"); |
| break; |
| case MIG_STATE_CANCELLED: |
| info->has_status = true; |
| info->status = g_strdup("cancelled"); |
| break; |
| } |
| |
| return info; |
| } |
| |
| /* shared migration helpers */ |
| |
| static void migrate_fd_monitor_suspend(MigrationState *s, Monitor *mon) |
| { |
| if (monitor_suspend(mon) == 0) { |
| DPRINTF("suspending monitor\n"); |
| } else { |
| monitor_printf(mon, "terminal does not allow synchronous " |
| "migration, continuing detached\n"); |
| } |
| } |
| |
| static int migrate_fd_cleanup(MigrationState *s) |
| { |
| int ret = 0; |
| |
| qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL); |
| |
| if (s->file) { |
| DPRINTF("closing file\n"); |
| if (qemu_fclose(s->file) != 0) { |
| ret = -1; |
| } |
| s->file = NULL; |
| } else { |
| if (s->mon) { |
| monitor_resume(s->mon); |
| } |
| } |
| |
| if (s->fd != -1) { |
| close(s->fd); |
| s->fd = -1; |
| } |
| |
| return ret; |
| } |
| |
| void migrate_fd_error(MigrationState *s) |
| { |
| DPRINTF("setting error state\n"); |
| s->state = MIG_STATE_ERROR; |
| notifier_list_notify(&migration_state_notifiers, s); |
| migrate_fd_cleanup(s); |
| } |
| |
| static void migrate_fd_completed(MigrationState *s) |
| { |
| DPRINTF("setting completed state\n"); |
| if (migrate_fd_cleanup(s) < 0) { |
| s->state = MIG_STATE_ERROR; |
| } else { |
| s->state = MIG_STATE_COMPLETED; |
| runstate_set(RUN_STATE_POSTMIGRATE); |
| } |
| notifier_list_notify(&migration_state_notifiers, s); |
| } |
| |
| static void migrate_fd_put_notify(void *opaque) |
| { |
| MigrationState *s = opaque; |
| |
| qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL); |
| qemu_file_put_notify(s->file); |
| if (s->file && qemu_file_get_error(s->file)) { |
| migrate_fd_error(s); |
| } |
| } |
| |
| static ssize_t migrate_fd_put_buffer(void *opaque, const void *data, |
| size_t size) |
| { |
| MigrationState *s = opaque; |
| ssize_t ret; |
| |
| if (s->state != MIG_STATE_ACTIVE) { |
| return -EIO; |
| } |
| |
| do { |
| ret = s->write(s, data, size); |
| } while (ret == -1 && ((s->get_error(s)) == EINTR)); |
| |
| if (ret == -1) |
| ret = -(s->get_error(s)); |
| |
| if (ret == -EAGAIN) { |
| qemu_set_fd_handler2(s->fd, NULL, NULL, migrate_fd_put_notify, s); |
| } |
| |
| return ret; |
| } |
| |
| static void migrate_fd_put_ready(void *opaque) |
| { |
| MigrationState *s = opaque; |
| int ret; |
| |
| if (s->state != MIG_STATE_ACTIVE) { |
| DPRINTF("put_ready returning because of non-active state\n"); |
| return; |
| } |
| |
| DPRINTF("iterate\n"); |
| ret = qemu_savevm_state_iterate(s->mon, s->file); |
| if (ret < 0) { |
| migrate_fd_error(s); |
| } else if (ret == 1) { |
| int old_vm_running = runstate_is_running(); |
| |
| DPRINTF("done iterating\n"); |
| vm_stop_force_state(RUN_STATE_FINISH_MIGRATE); |
| |
| if (qemu_savevm_state_complete(s->mon, s->file) < 0) { |
| migrate_fd_error(s); |
| } else { |
| migrate_fd_completed(s); |
| } |
| if (s->state != MIG_STATE_COMPLETED) { |
| if (old_vm_running) { |
| vm_start(); |
| } |
| } |
| } |
| } |
| |
| static void migrate_fd_cancel(MigrationState *s) |
| { |
| if (s->state != MIG_STATE_ACTIVE) |
| return; |
| |
| DPRINTF("cancelling migration\n"); |
| |
| s->state = MIG_STATE_CANCELLED; |
| notifier_list_notify(&migration_state_notifiers, s); |
| qemu_savevm_state_cancel(s->mon, s->file); |
| |
| migrate_fd_cleanup(s); |
| } |
| |
| static void migrate_fd_wait_for_unfreeze(void *opaque) |
| { |
| MigrationState *s = opaque; |
| int ret; |
| |
| DPRINTF("wait for unfreeze\n"); |
| if (s->state != MIG_STATE_ACTIVE) |
| return; |
| |
| do { |
| fd_set wfds; |
| |
| FD_ZERO(&wfds); |
| FD_SET(s->fd, &wfds); |
| |
| ret = select(s->fd + 1, NULL, &wfds, NULL, NULL); |
| } while (ret == -1 && (s->get_error(s)) == EINTR); |
| |
| if (ret == -1) { |
| qemu_file_set_error(s->file, -s->get_error(s)); |
| } |
| } |
| |
| static int migrate_fd_close(void *opaque) |
| { |
| MigrationState *s = opaque; |
| |
| if (s->mon) { |
| monitor_resume(s->mon); |
| } |
| qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL); |
| return s->close(s); |
| } |
| |
| void add_migration_state_change_notifier(Notifier *notify) |
| { |
| notifier_list_add(&migration_state_notifiers, notify); |
| } |
| |
| void remove_migration_state_change_notifier(Notifier *notify) |
| { |
| notifier_list_remove(&migration_state_notifiers, notify); |
| } |
| |
| bool migration_is_active(MigrationState *s) |
| { |
| return s->state == MIG_STATE_ACTIVE; |
| } |
| |
| bool migration_has_finished(MigrationState *s) |
| { |
| return s->state == MIG_STATE_COMPLETED; |
| } |
| |
| bool migration_has_failed(MigrationState *s) |
| { |
| return (s->state == MIG_STATE_CANCELLED || |
| s->state == MIG_STATE_ERROR); |
| } |
| |
| void migrate_fd_connect(MigrationState *s) |
| { |
| int ret; |
| |
| s->state = MIG_STATE_ACTIVE; |
| s->file = qemu_fopen_ops_buffered(s, |
| s->bandwidth_limit, |
| migrate_fd_put_buffer, |
| migrate_fd_put_ready, |
| migrate_fd_wait_for_unfreeze, |
| migrate_fd_close); |
| |
| DPRINTF("beginning savevm\n"); |
| ret = qemu_savevm_state_begin(s->mon, s->file, s->blk, s->shared); |
| if (ret < 0) { |
| DPRINTF("failed, %d\n", ret); |
| migrate_fd_error(s); |
| return; |
| } |
| migrate_fd_put_ready(s); |
| } |
| |
| static MigrationState *migrate_init(Monitor *mon, int detach, int blk, int inc) |
| { |
| MigrationState *s = migrate_get_current(); |
| int64_t bandwidth_limit = s->bandwidth_limit; |
| |
| memset(s, 0, sizeof(*s)); |
| s->bandwidth_limit = bandwidth_limit; |
| s->blk = blk; |
| s->shared = inc; |
| |
| /* s->mon is used for two things: |
| - pass fd in fd migration |
| - suspend/resume monitor for not detached migration |
| */ |
| s->mon = mon; |
| s->bandwidth_limit = bandwidth_limit; |
| s->state = MIG_STATE_SETUP; |
| |
| if (!detach) { |
| migrate_fd_monitor_suspend(s, mon); |
| } |
| |
| return s; |
| } |
| |
| int do_migrate(Monitor *mon, const QDict *qdict, QObject **ret_data) |
| { |
| MigrationState *s = migrate_get_current(); |
| const char *p; |
| int detach = qdict_get_try_bool(qdict, "detach", 0); |
| int blk = qdict_get_try_bool(qdict, "blk", 0); |
| int inc = qdict_get_try_bool(qdict, "inc", 0); |
| const char *uri = qdict_get_str(qdict, "uri"); |
| int ret; |
| |
| if (s->state == MIG_STATE_ACTIVE) { |
| monitor_printf(mon, "migration already in progress\n"); |
| return -1; |
| } |
| |
| if (qemu_savevm_state_blocked(mon)) { |
| return -1; |
| } |
| |
| s = migrate_init(mon, detach, blk, inc); |
| |
| if (strstart(uri, "tcp:", &p)) { |
| ret = tcp_start_outgoing_migration(s, p); |
| #if !defined(WIN32) |
| } else if (strstart(uri, "exec:", &p)) { |
| ret = exec_start_outgoing_migration(s, p); |
| } else if (strstart(uri, "unix:", &p)) { |
| ret = unix_start_outgoing_migration(s, p); |
| } else if (strstart(uri, "fd:", &p)) { |
| ret = fd_start_outgoing_migration(s, p); |
| #endif |
| } else { |
| monitor_printf(mon, "unknown migration protocol: %s\n", uri); |
| ret = -EINVAL; |
| } |
| |
| if (ret < 0) { |
| monitor_printf(mon, "migration failed: %s\n", strerror(-ret)); |
| return ret; |
| } |
| |
| if (detach) { |
| s->mon = NULL; |
| } |
| |
| notifier_list_notify(&migration_state_notifiers, s); |
| return 0; |
| } |
| |
| int do_migrate_cancel(Monitor *mon, const QDict *qdict, QObject **ret_data) |
| { |
| migrate_fd_cancel(migrate_get_current()); |
| return 0; |
| } |
| |
| int do_migrate_set_speed(Monitor *mon, const QDict *qdict, QObject **ret_data) |
| { |
| int64_t d; |
| MigrationState *s; |
| |
| d = qdict_get_int(qdict, "value"); |
| if (d < 0) { |
| d = 0; |
| } |
| |
| s = migrate_get_current(); |
| s->bandwidth_limit = d; |
| qemu_file_set_rate_limit(s->file, s->bandwidth_limit); |
| |
| return 0; |
| } |
| |
| int do_migrate_set_downtime(Monitor *mon, const QDict *qdict, |
| QObject **ret_data) |
| { |
| double d; |
| |
| d = qdict_get_double(qdict, "value") * 1e9; |
| d = MAX(0, MIN(UINT64_MAX, d)); |
| max_downtime = (uint64_t)d; |
| |
| return 0; |
| } |