From ddfc29076293a794f0d9cc74c0c822c144e7ecbc Mon Sep 17 00:00:00 2001 From: Wolfgang Bumiller Date: Wed, 9 Dec 2015 16:04:32 +0100 Subject: [PATCH 22/47] internal snapshot async --- Makefile.objs | 1 + block.c | 2 +- hmp-commands-info.hx | 13 ++ hmp-commands.hx | 32 +++ hmp.c | 57 ++++++ hmp.h | 5 + include/block/block.h | 1 + include/sysemu/sysemu.h | 5 +- migration/savevm.c | 12 +- qapi-schema.json | 46 +++++ qemu-options.hx | 13 ++ qmp-commands.hx | 30 +++ savevm-async.c | 526 ++++++++++++++++++++++++++++++++++++++++++++++++ vl.c | 8 + 14 files changed, 743 insertions(+), 8 deletions(-) create mode 100644 savevm-async.c diff --git a/Makefile.objs b/Makefile.objs index 845edd0..7d9d2d7 100644 --- a/Makefile.objs +++ b/Makefile.objs @@ -53,6 +53,7 @@ common-obj-$(CONFIG_LINUX) += fsdev/ common-obj-y += migration/ common-obj-y += qemu-char.o #aio.o common-obj-y += page_cache.o +common-obj-y += savevm-async.o common-obj-$(CONFIG_SPICE) += spice-qemu-char.o diff --git a/block.c b/block.c index 30d64e6..95c1d32 100644 --- a/block.c +++ b/block.c @@ -2288,7 +2288,7 @@ void bdrv_replace_in_backing_chain(BlockDriverState *old, BlockDriverState *new) bdrv_unref(old); } -static void bdrv_delete(BlockDriverState *bs) +void bdrv_delete(BlockDriverState *bs) { assert(!bs->job); assert(bdrv_op_blocker_is_empty(bs)); diff --git a/hmp-commands-info.hx b/hmp-commands-info.hx index 7616fe2..3046f9d 100644 --- a/hmp-commands-info.hx +++ b/hmp-commands-info.hx @@ -588,6 +588,19 @@ Show current migration xbzrle cache size. ETEXI { + .name = "savevm", + .args_type = "", + .params = "", + .help = "show savevm status", + .mhandler.cmd = hmp_info_savevm, + }, + +STEXI +@item info savevm +show savevm status +ETEXI + + { .name = "balloon", .args_type = "", .params = "", diff --git a/hmp-commands.hx b/hmp-commands.hx index 0e20ef9..4d735cb 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -1791,3 +1791,35 @@ ETEXI STEXI @end table ETEXI + + { + .name = "savevm-start", + .args_type = "statefile:s?", + .params = "[statefile]", + .help = "Prepare for snapshot and halt VM. Save VM state to statefile.", + .mhandler.cmd = hmp_savevm_start, + }, + + { + .name = "snapshot-drive", + .args_type = "device:s,name:s", + .params = "device name", + .help = "Create internal snapshot.", + .mhandler.cmd = hmp_snapshot_drive, + }, + + { + .name = "delete-drive-snapshot", + .args_type = "device:s,name:s", + .params = "device name", + .help = "Delete internal snapshot.", + .mhandler.cmd = hmp_delete_drive_snapshot, + }, + + { + .name = "savevm-end", + .args_type = "", + .params = "", + .help = "Resume VM after snaphot.", + .mhandler.cmd = hmp_savevm_end, + }, diff --git a/hmp.c b/hmp.c index c23cf2f..030fd97 100644 --- a/hmp.c +++ b/hmp.c @@ -2117,6 +2117,63 @@ void hmp_info_memory_devices(Monitor *mon, const QDict *qdict) qapi_free_MemoryDeviceInfoList(info_list); } +void hmp_savevm_start(Monitor *mon, const QDict *qdict) +{ + Error *errp = NULL; + const char *statefile = qdict_get_try_str(qdict, "statefile"); + + qmp_savevm_start(statefile != NULL, statefile, &errp); + hmp_handle_error(mon, &errp); +} + +void hmp_snapshot_drive(Monitor *mon, const QDict *qdict) +{ + Error *errp = NULL; + const char *name = qdict_get_str(qdict, "name"); + const char *device = qdict_get_str(qdict, "device"); + + qmp_snapshot_drive(device, name, &errp); + hmp_handle_error(mon, &errp); +} + +void hmp_delete_drive_snapshot(Monitor *mon, const QDict *qdict) +{ + Error *errp = NULL; + const char *name = qdict_get_str(qdict, "name"); + const char *device = qdict_get_str(qdict, "device"); + + qmp_delete_drive_snapshot(device, name, &errp); + hmp_handle_error(mon, &errp); +} + +void hmp_savevm_end(Monitor *mon, const QDict *qdict) +{ + Error *errp = NULL; + + qmp_savevm_end(&errp); + hmp_handle_error(mon, &errp); +} + +void hmp_info_savevm(Monitor *mon, const QDict *qdict) +{ + SaveVMInfo *info; + info = qmp_query_savevm(NULL); + + if (info->has_status) { + monitor_printf(mon, "savevm status: %s\n", info->status); + monitor_printf(mon, "total time: %" PRIu64 " milliseconds\n", + info->total_time); + } else { + monitor_printf(mon, "savevm status: not running\n"); + } + if (info->has_bytes) { + monitor_printf(mon, "Bytes saved: %"PRIu64"\n", info->bytes); + } + if (info->has_error) { + monitor_printf(mon, "Error: %s\n", info->error); + } +} + void hmp_info_iothreads(Monitor *mon, const QDict *qdict) { IOThreadInfoList *info_list = qmp_query_iothreads(NULL); diff --git a/hmp.h b/hmp.h index 9a4c1f6..b74ddbf 100644 --- a/hmp.h +++ b/hmp.h @@ -26,6 +26,7 @@ void hmp_info_status(Monitor *mon, const QDict *qdict); void hmp_info_uuid(Monitor *mon, const QDict *qdict); void hmp_info_chardev(Monitor *mon, const QDict *qdict); void hmp_info_mice(Monitor *mon, const QDict *qdict); +void hmp_info_savevm(Monitor *mon, const QDict *qdict); void hmp_info_migrate(Monitor *mon, const QDict *qdict); void hmp_info_migrate_capabilities(Monitor *mon, const QDict *qdict); void hmp_info_migrate_parameters(Monitor *mon, const QDict *qdict); @@ -92,6 +93,10 @@ void hmp_netdev_add(Monitor *mon, const QDict *qdict); void hmp_netdev_del(Monitor *mon, const QDict *qdict); void hmp_getfd(Monitor *mon, const QDict *qdict); void hmp_closefd(Monitor *mon, const QDict *qdict); +void hmp_savevm_start(Monitor *mon, const QDict *qdict); +void hmp_snapshot_drive(Monitor *mon, const QDict *qdict); +void hmp_delete_drive_snapshot(Monitor *mon, const QDict *qdict); +void hmp_savevm_end(Monitor *mon, const QDict *qdict); void hmp_sendkey(Monitor *mon, const QDict *qdict); void hmp_screendump(Monitor *mon, const QDict *qdict); void hmp_nbd_server_start(Monitor *mon, const QDict *qdict); diff --git a/include/block/block.h b/include/block/block.h index acddf3b..0f70a9d 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -256,6 +256,7 @@ BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, int bdrv_get_backing_file_depth(BlockDriverState *bs); void bdrv_refresh_filename(BlockDriverState *bs); int bdrv_truncate(BlockDriverState *bs, int64_t offset); +void bdrv_delete(BlockDriverState *bs); int64_t bdrv_nb_sectors(BlockDriverState *bs); int64_t bdrv_getlength(BlockDriverState *bs); int64_t bdrv_get_allocated_file_size(BlockDriverState *bs); diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h index ee7c760..4875441 100644 --- a/include/sysemu/sysemu.h +++ b/include/sysemu/sysemu.h @@ -79,6 +79,7 @@ void qemu_remove_machine_init_done_notifier(Notifier *notify); void hmp_savevm(Monitor *mon, const QDict *qdict); int load_vmstate(const char *name); +int load_state_from_blockdev(const char *filename); void hmp_delvm(Monitor *mon, const QDict *qdict); void hmp_info_snapshots(Monitor *mon, const QDict *qdict); @@ -106,13 +107,13 @@ enum qemu_vm_cmd { #define MAX_VM_CMD_PACKAGED_SIZE (1ul << 24) bool qemu_savevm_state_blocked(Error **errp); -void qemu_savevm_state_begin(QEMUFile *f, +int qemu_savevm_state_begin(QEMUFile *f, const MigrationParams *params); void qemu_savevm_state_header(QEMUFile *f); int qemu_savevm_state_iterate(QEMUFile *f, bool postcopy); void qemu_savevm_state_cleanup(void); void qemu_savevm_state_complete_postcopy(QEMUFile *f); -void qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only); +int qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only); void qemu_savevm_state_pending(QEMUFile *f, uint64_t max_size, uint64_t *res_non_postcopiable, uint64_t *res_postcopiable); diff --git a/migration/savevm.c b/migration/savevm.c index 33a2911..b1bdfb6 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -879,11 +879,11 @@ void qemu_savevm_state_header(QEMUFile *f) } -void qemu_savevm_state_begin(QEMUFile *f, +int qemu_savevm_state_begin(QEMUFile *f, const MigrationParams *params) { SaveStateEntry *se; - int ret; + int ret = 0; trace_savevm_state_begin(); QTAILQ_FOREACH(se, &savevm_state.handlers, entry) { @@ -911,6 +911,7 @@ void qemu_savevm_state_begin(QEMUFile *f, break; } } + return ret; } /* @@ -1014,7 +1015,7 @@ void qemu_savevm_state_complete_postcopy(QEMUFile *f) qemu_fflush(f); } -void qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only) +int qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only) { QJSON *vmdesc; int vmdesc_len; @@ -1048,12 +1049,12 @@ void qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only) save_section_footer(f, se); if (ret < 0) { qemu_file_set_error(f, ret); - return; + return ret; } } if (iterable_only) { - return; + return ret; } vmdesc = qjson_new(); @@ -1100,6 +1101,7 @@ void qemu_savevm_state_complete_precopy(QEMUFile *f, bool iterable_only) qjson_destroy(vmdesc); qemu_fflush(f); + return qemu_file_get_error(f); } /* Give an estimate of the amount left to be transferred, diff --git a/qapi-schema.json b/qapi-schema.json index 147137d..0c0faf7 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -594,6 +594,42 @@ '*cpu-throttle-percentage': 'int', '*error-desc': 'str'} } + +# @SaveVMInfo +# +# Information about current migration process. +# +# @status: #optional string describing the current savevm status. +# This can be 'active', 'completed', 'failed'. +# If this field is not returned, no savevm process +# has been initiated +# +# @error: #optional string containing error message is status is failed. +# +# @total-time: #optional total amount of milliseconds since savevm started. +# If savevm has ended, it returns the total save time +# +# @bytes: #optional total amount of data transfered +# +# Since: 1.3 +## +{ 'struct': 'SaveVMInfo', + 'data': {'*status': 'str', '*error': 'str', + '*total-time': 'int', '*bytes': 'int'} } + +## +# @query-savevm +# +# Returns information about current savevm process. +# +# Returns: @SaveVMInfo +# +# Since: 1.3 +## +{ 'command': 'query-savevm', 'returns': 'SaveVMInfo' } + +## + ## # @query-migrate # @@ -3286,8 +3322,18 @@ # # Since: 1.2.0 ## + { 'command': 'query-target', 'returns': 'TargetInfo' } +{ 'command': 'savevm-start', 'data': { '*statefile': 'str' } } + +{ 'command': 'snapshot-drive', 'data': { 'device': 'str', 'name': 'str' } } + +{ 'command': 'delete-drive-snapshot', 'data': { 'device': 'str', 'name': 'str' } } + +{ 'command': 'savevm-end' } + + ## # @QKeyCode: # diff --git a/qemu-options.hx b/qemu-options.hx index a71aaf8..37fad3b 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -3302,6 +3302,19 @@ STEXI Start right away with a saved state (@code{loadvm} in monitor) ETEXI +DEF("loadstate", HAS_ARG, QEMU_OPTION_loadstate, \ + "-loadstate file\n" \ + " start right away with a saved state\n", + QEMU_ARCH_ALL) +STEXI +@item -loadstate @var{file} +@findex -loadstate +Start right away with a saved state. This option does not rollback +disk state like @code{loadvm}, so user must make sure that disk +have correct state. @var{file} can be any valid device URL. See the section +for "Device URL Syntax" for more information. +ETEXI + #ifndef _WIN32 DEF("daemonize", 0, QEMU_OPTION_daemonize, \ "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) diff --git a/qmp-commands.hx b/qmp-commands.hx index a8e8522..6342cd2 100644 --- a/qmp-commands.hx +++ b/qmp-commands.hx @@ -4904,6 +4904,36 @@ Example: EQMP { + .name = "savevm-start", + .args_type = "statefile:s?", + .mhandler.cmd_new = qmp_marshal_savevm_start, + }, + + { + .name = "snapshot-drive", + .args_type = "device:s,name:s", + .mhandler.cmd_new = qmp_marshal_snapshot_drive, + }, + + { + .name = "delete-drive-snapshot", + .args_type = "device:s,name:s", + .mhandler.cmd_new = qmp_marshal_delete_drive_snapshot, + }, + + { + .name = "savevm-end", + .args_type = "", + .mhandler.cmd_new = qmp_marshal_savevm_end, + }, + + { + .name = "query-savevm", + .args_type = "", + .mhandler.cmd_new = qmp_marshal_query_savevm, + }, + + { .name = "query-rocker", .args_type = "name:s", .mhandler.cmd_new = qmp_marshal_query_rocker, diff --git a/savevm-async.c b/savevm-async.c new file mode 100644 index 0000000..ae7ea84 --- /dev/null +++ b/savevm-async.c @@ -0,0 +1,526 @@ +#include "qemu/osdep.h" +#include "qemu-common.h" +#include "qapi/qmp/qerror.h" +#include "qemu/error-report.h" +#include "sysemu/sysemu.h" +#include "qmp-commands.h" +#include "qemu-options.h" +#include "migration/qemu-file.h" +#include "qom/qom-qobject.h" +#include "migration/migration.h" +#include "block/snapshot.h" +#include "block/qapi.h" +#include "block/block.h" +#include "qemu/timer.h" +#include "sysemu/block-backend.h" +#include "qapi/qmp/qstring.h" +#include "qemu/rcu.h" +#include "qemu/thread.h" +#include "qemu/cutils.h" + +/* #define DEBUG_SAVEVM_STATE */ + +#ifdef DEBUG_SAVEVM_STATE +#define DPRINTF(fmt, ...) \ + do { printf("savevm-async: " fmt, ## __VA_ARGS__); } while (0) +#else +#define DPRINTF(fmt, ...) \ + do { } while (0) +#endif + +enum { + SAVE_STATE_DONE, + SAVE_STATE_ERROR, + SAVE_STATE_ACTIVE, + SAVE_STATE_COMPLETED, + SAVE_STATE_CANCELLED +}; + + +static struct SnapshotState { + BlockDriverState *bs; + size_t bs_pos; + int state; + Error *error; + Error *blocker; + int saved_vm_running; + QEMUFile *file; + int64_t total_time; +} snap_state; + +SaveVMInfo *qmp_query_savevm(Error **errp) +{ + SaveVMInfo *info = g_malloc0(sizeof(*info)); + struct SnapshotState *s = &snap_state; + + if (s->state != SAVE_STATE_DONE) { + info->has_bytes = true; + info->bytes = s->bs_pos; + switch (s->state) { + case SAVE_STATE_ERROR: + info->has_status = true; + info->status = g_strdup("failed"); + info->has_total_time = true; + info->total_time = s->total_time; + if (s->error) { + info->has_error = true; + info->error = g_strdup(error_get_pretty(s->error)); + } + break; + case SAVE_STATE_ACTIVE: + info->has_status = true; + info->status = g_strdup("active"); + info->has_total_time = true; + info->total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + - s->total_time; + break; + case SAVE_STATE_COMPLETED: + info->has_status = true; + info->status = g_strdup("completed"); + info->has_total_time = true; + info->total_time = s->total_time; + break; + } + } + + return info; +} + +static int save_snapshot_cleanup(void) +{ + int ret = 0; + + DPRINTF("save_snapshot_cleanup\n"); + + snap_state.total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) - + snap_state.total_time; + + if (snap_state.file) { + ret = qemu_fclose(snap_state.file); + } + + if (snap_state.bs) { + /* try to truncate, but ignore errors (will fail on block devices). + * note: bdrv_read() need whole blocks, so we round up + */ + size_t size = (snap_state.bs_pos + BDRV_SECTOR_SIZE) & BDRV_SECTOR_MASK; + bdrv_truncate(snap_state.bs, size); + bdrv_op_unblock_all(snap_state.bs, snap_state.blocker); + error_free(snap_state.blocker); + snap_state.blocker = NULL; + bdrv_unref(snap_state.bs); + snap_state.bs = NULL; + } + + return ret; +} + +static void save_snapshot_error(const char *fmt, ...) +{ + va_list ap; + char *msg; + + va_start(ap, fmt); + msg = g_strdup_vprintf(fmt, ap); + va_end(ap); + + DPRINTF("save_snapshot_error: %s\n", msg); + + if (!snap_state.error) { + error_set(&snap_state.error, ERROR_CLASS_GENERIC_ERROR, "%s", msg); + } + + g_free (msg); + + snap_state.state = SAVE_STATE_ERROR; + + save_snapshot_cleanup(); +} + +static void save_snapshot_completed(void) +{ + DPRINTF("save_snapshot_completed\n"); + + if (save_snapshot_cleanup() < 0) { + snap_state.state = SAVE_STATE_ERROR; + } else { + snap_state.state = SAVE_STATE_COMPLETED; + } +} + +static int block_state_close(void *opaque) +{ + snap_state.file = NULL; + return bdrv_flush(snap_state.bs); +} + +static int block_state_put_buffer(void *opaque, const uint8_t *buf, + int64_t pos, int size) +{ + int ret; + + assert(pos == snap_state.bs_pos); + + if ((ret = bdrv_pwrite(snap_state.bs, snap_state.bs_pos, buf, size)) > 0) { + snap_state.bs_pos += ret; + } + + return ret; +} + +static int store_and_stop(void) { + if (global_state_store()) { + save_snapshot_error("Error saving global state"); + return 1; + } + if (runstate_is_running()) { + vm_stop(RUN_STATE_SAVE_VM); + } + return 0; +} + +static void process_savevm_co(void *opaque) +{ + int ret; + int64_t maxlen; + MigrationParams params = { + .blk = 0, + .shared = 0 + }; + + snap_state.state = SAVE_STATE_ACTIVE; + + qemu_mutex_unlock_iothread(); + qemu_savevm_state_header(snap_state.file); + ret = qemu_savevm_state_begin(snap_state.file, ¶ms); + qemu_mutex_lock_iothread(); + + if (ret < 0) { + save_snapshot_error("qemu_savevm_state_begin failed"); + return; + } + + while (snap_state.state == SAVE_STATE_ACTIVE) { + uint64_t pending_size; + + pending_size = qemu_savevm_state_pending(snap_state.file, 0); + + if (pending_size) { + ret = qemu_savevm_state_iterate(snap_state.file); + if (ret < 0) { + save_snapshot_error("qemu_savevm_state_iterate error %d", ret); + break; + } + DPRINTF("savevm inerate pending size %lu ret %d\n", pending_size, ret); + } else { + DPRINTF("done iterating\n"); + if (store_and_stop()) + break; + DPRINTF("savevm inerate finished\n"); + qemu_savevm_state_complete_precopy(snap_state.file); + DPRINTF("save complete\n"); + save_snapshot_completed(); + break; + } + + /* stop the VM if we get to the end of available space, + * or if pending_size is just a few MB + */ + maxlen = bdrv_getlength(snap_state.bs) - 30*1024*1024; + if ((pending_size < 100000) || + ((snap_state.bs_pos + pending_size) >= maxlen)) { + if (store_and_stop()) + break; + } + } + + if(snap_state.state == SAVE_STATE_CANCELLED) { + save_snapshot_completed(); + Error *errp = NULL; + qmp_savevm_end(&errp); + } + +} + +static const QEMUFileOps block_file_ops = { + .put_buffer = block_state_put_buffer, + .close = block_state_close, +}; + + +void qmp_savevm_start(bool has_statefile, const char *statefile, Error **errp) +{ + BlockDriver *drv = NULL; + Error *local_err = NULL; + + int bdrv_oflags = BDRV_O_RDWR; + int ret; + + if (snap_state.state != SAVE_STATE_DONE) { + error_set(errp, ERROR_CLASS_GENERIC_ERROR, + "VM snapshot already started\n"); + return; + } + + /* initialize snapshot info */ + snap_state.saved_vm_running = runstate_is_running(); + snap_state.bs_pos = 0; + snap_state.total_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); + snap_state.blocker = NULL; + + if (snap_state.error) { + error_free(snap_state.error); + snap_state.error = NULL; + } + + if (!has_statefile) { + vm_stop(RUN_STATE_SAVE_VM); + snap_state.state = SAVE_STATE_COMPLETED; + return; + } + + if (qemu_savevm_state_blocked(errp)) { + return; + } + + /* Open the image */ + snap_state.bs = bdrv_new(); + + QDict *options = NULL; + options = qdict_new(); + qdict_put(options, "driver", qstring_from_str("raw")); + ret = bdrv_open(&snap_state.bs, statefile, NULL, options, bdrv_oflags, drv, &local_err); + if (ret < 0) { + error_set(errp, ERROR_CLASS_GENERIC_ERROR, "failed to open '%s'", statefile); + goto restart; + } + + snap_state.file = qemu_fopen_ops(&snap_state, &block_file_ops); + + if (!snap_state.file) { + error_set(errp, ERROR_CLASS_GENERIC_ERROR, "failed to open '%s'", statefile); + goto restart; + } + + + error_setg(&snap_state.blocker, "block device is in use by savevm"); + bdrv_op_block_all(snap_state.bs, snap_state.blocker); + + Coroutine *co = qemu_coroutine_create(process_savevm_co); + qemu_coroutine_enter(co); + + return; + +restart: + + save_snapshot_error("setup failed"); + + if (snap_state.saved_vm_running) { + vm_start(); + } +} + +void qmp_savevm_end(Error **errp) +{ + if (snap_state.state == SAVE_STATE_DONE) { + error_set(errp, ERROR_CLASS_GENERIC_ERROR, + "VM snapshot not started\n"); + return; + } + + if (snap_state.state == SAVE_STATE_ACTIVE) { + snap_state.state = SAVE_STATE_CANCELLED; + return; + } + + if (snap_state.saved_vm_running) { + vm_start(); + } + + snap_state.state = SAVE_STATE_DONE; +} + +void qmp_snapshot_drive(const char *device, const char *name, Error **errp) +{ + BlockBackend *blk; + BlockDriverState *bs; + QEMUSnapshotInfo sn1, *sn = &sn1; + int ret; +#ifdef _WIN32 + struct _timeb tb; +#else + struct timeval tv; +#endif + + if (snap_state.state != SAVE_STATE_COMPLETED) { + error_set(errp, ERROR_CLASS_GENERIC_ERROR, + "VM snapshot not ready/started\n"); + return; + } + + blk = blk_by_name(device); + if (!blk) { + error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND, + "Device '%s' not found", device); + return; + } + + bs = blk_bs(blk); + if (!bdrv_is_inserted(bs)) { + error_setg(errp, QERR_DEVICE_HAS_NO_MEDIUM, device); + return; + } + + if (bdrv_is_read_only(bs)) { + error_setg(errp, "Node '%s' is read only", device); + return; + } + + if (!bdrv_can_snapshot(bs)) { + error_setg(errp, QERR_UNSUPPORTED); + return; + } + + if (bdrv_snapshot_find(bs, sn, name) >= 0) { + error_set(errp, ERROR_CLASS_GENERIC_ERROR, + "snapshot '%s' already exists", name); + return; + } + + sn = &sn1; + memset(sn, 0, sizeof(*sn)); + +#ifdef _WIN32 + _ftime(&tb); + sn->date_sec = tb.time; + sn->date_nsec = tb.millitm * 1000000; +#else + gettimeofday(&tv, NULL); + sn->date_sec = tv.tv_sec; + sn->date_nsec = tv.tv_usec * 1000; +#endif + sn->vm_clock_nsec = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); + + pstrcpy(sn->name, sizeof(sn->name), name); + + sn->vm_state_size = 0; /* do not save state */ + + ret = bdrv_snapshot_create(bs, sn); + if (ret < 0) { + error_set(errp, ERROR_CLASS_GENERIC_ERROR, + "Error while creating snapshot on '%s'\n", device); + return; + } +} + +void qmp_delete_drive_snapshot(const char *device, const char *name, + Error **errp) +{ + BlockBackend *blk; + BlockDriverState *bs; + QEMUSnapshotInfo sn1, *sn = &sn1; + Error *local_err = NULL; + + int ret; + + blk = blk_by_name(device); + if (!blk) { + error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND, + "Device '%s' not found", device); + return; + } + + bs = blk_bs(blk); + if (bdrv_is_read_only(bs)) { + error_setg(errp, "Node '%s' is read only", device); + return; + } + + if (!bdrv_can_snapshot(bs)) { + error_setg(errp, QERR_UNSUPPORTED); + return; + } + + if (bdrv_snapshot_find(bs, sn, name) < 0) { + /* return success if snapshot does not exists */ + return; + } + + ret = bdrv_snapshot_delete(bs, NULL, name, &local_err); + if (ret < 0) { + error_set(errp, ERROR_CLASS_GENERIC_ERROR, + "Error while deleting snapshot on '%s'\n", device); + return; + } +} + +static int loadstate_get_buffer(void *opaque, uint8_t *buf, int64_t pos, + int size) +{ + BlockDriverState *bs = (BlockDriverState *)opaque; + int64_t maxlen = bdrv_getlength(bs); + if (pos > maxlen) { + return -EIO; + } + if ((pos + size) > maxlen) { + size = maxlen - pos - 1; + } + if (size == 0) { + return 0; + } + return bdrv_pread(bs, pos, buf, size); +} + +static const QEMUFileOps loadstate_file_ops = { + .get_buffer = loadstate_get_buffer, +}; + +int load_state_from_blockdev(const char *filename) +{ + BlockDriverState *bs = NULL; + BlockDriver *drv = NULL; + Error *local_err = NULL; + Error *blocker = NULL; + + QEMUFile *f; + int ret; + + bs = bdrv_new(); + ret = bdrv_open(&bs, filename, NULL, NULL, 0, drv, &local_err); + error_setg(&blocker, "block device is in use by load state"); + bdrv_op_block_all(bs, blocker); + + if (ret < 0) { + error_report("Could not open VM state file"); + goto the_end; + } + + /* restore the VM state */ + f = qemu_fopen_ops(bs, &loadstate_file_ops); + if (!f) { + error_report("Could not open VM state file"); + ret = -EINVAL; + goto the_end; + } + + 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); + goto the_end; + } + + ret = 0; + + the_end: + if (bs) { + bdrv_op_unblock_all(bs, blocker); + error_free(blocker); + bdrv_unref(bs); + } + return ret; +} diff --git a/vl.c b/vl.c index b226e0b..c01b1b5 100644 --- a/vl.c +++ b/vl.c @@ -2962,6 +2962,7 @@ int main(int argc, char **argv, char **envp) int optind; const char *optarg; const char *loadvm = NULL; + const char *loadstate = NULL; MachineClass *machine_class; const char *cpu_model; const char *vga_model = NULL; @@ -3603,6 +3604,9 @@ int main(int argc, char **argv, char **envp) case QEMU_OPTION_loadvm: loadvm = optarg; break; + case QEMU_OPTION_loadstate: + loadstate = optarg; + break; case QEMU_OPTION_full_screen: full_screen = 1; break; @@ -4597,6 +4601,10 @@ int main(int argc, char **argv, char **envp) if (load_vmstate(loadvm) < 0) { autostart = 0; } + } else if (loadstate) { + if (load_state_from_blockdev(loadstate) < 0) { + autostart = 0; + } } qdev_prop_check_globals(); -- 2.1.4