Marc-André Lureau | 5010cec | 2019-12-16 11:48:53 +0400 | [diff] [blame^] | 1 | /* |
| 2 | * QEMU dbus-vmstate |
| 3 | * |
| 4 | * Copyright (C) 2019 Red Hat Inc |
| 5 | * |
| 6 | * Authors: |
| 7 | * Marc-André Lureau <marcandre.lureau@redhat.com> |
| 8 | * |
| 9 | * This work is licensed under the terms of the GNU GPL, version 2 or later. |
| 10 | * See the COPYING file in the top-level directory. |
| 11 | */ |
| 12 | |
| 13 | #include "qemu/osdep.h" |
| 14 | #include "qemu/units.h" |
| 15 | #include "qemu/dbus.h" |
| 16 | #include "qemu/error-report.h" |
| 17 | #include "qapi/error.h" |
| 18 | #include "qom/object_interfaces.h" |
| 19 | #include "qapi/qmp/qerror.h" |
| 20 | #include "migration/vmstate.h" |
| 21 | #include "trace.h" |
| 22 | |
| 23 | typedef struct DBusVMState DBusVMState; |
| 24 | typedef struct DBusVMStateClass DBusVMStateClass; |
| 25 | |
| 26 | #define TYPE_DBUS_VMSTATE "dbus-vmstate" |
| 27 | #define DBUS_VMSTATE(obj) \ |
| 28 | OBJECT_CHECK(DBusVMState, (obj), TYPE_DBUS_VMSTATE) |
| 29 | #define DBUS_VMSTATE_GET_CLASS(obj) \ |
| 30 | OBJECT_GET_CLASS(DBusVMStateClass, (obj), TYPE_DBUS_VMSTATE) |
| 31 | #define DBUS_VMSTATE_CLASS(klass) \ |
| 32 | OBJECT_CLASS_CHECK(DBusVMStateClass, (klass), TYPE_DBUS_VMSTATE) |
| 33 | |
| 34 | struct DBusVMStateClass { |
| 35 | ObjectClass parent_class; |
| 36 | }; |
| 37 | |
| 38 | struct DBusVMState { |
| 39 | Object parent; |
| 40 | |
| 41 | GDBusConnection *bus; |
| 42 | char *dbus_addr; |
| 43 | char *id_list; |
| 44 | |
| 45 | uint32_t data_size; |
| 46 | uint8_t *data; |
| 47 | }; |
| 48 | |
| 49 | static const GDBusPropertyInfo vmstate_property_info[] = { |
| 50 | { -1, (char *) "Id", (char *) "s", |
| 51 | G_DBUS_PROPERTY_INFO_FLAGS_READABLE, NULL }, |
| 52 | }; |
| 53 | |
| 54 | static const GDBusPropertyInfo * const vmstate_property_info_pointers[] = { |
| 55 | &vmstate_property_info[0], |
| 56 | NULL |
| 57 | }; |
| 58 | |
| 59 | static const GDBusInterfaceInfo vmstate1_interface_info = { |
| 60 | -1, |
| 61 | (char *) "org.qemu.VMState1", |
| 62 | (GDBusMethodInfo **) NULL, |
| 63 | (GDBusSignalInfo **) NULL, |
| 64 | (GDBusPropertyInfo **) &vmstate_property_info_pointers, |
| 65 | NULL, |
| 66 | }; |
| 67 | |
| 68 | #define DBUS_VMSTATE_SIZE_LIMIT (1 * MiB) |
| 69 | |
| 70 | static GHashTable * |
| 71 | get_id_list_set(DBusVMState *self) |
| 72 | { |
| 73 | g_auto(GStrv) ids = NULL; |
| 74 | g_autoptr(GHashTable) set = NULL; |
| 75 | int i; |
| 76 | |
| 77 | if (!self->id_list) { |
| 78 | return NULL; |
| 79 | } |
| 80 | |
| 81 | ids = g_strsplit(self->id_list, ",", -1); |
| 82 | set = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, NULL); |
| 83 | for (i = 0; ids[i]; i++) { |
| 84 | g_hash_table_add(set, ids[i]); |
| 85 | ids[i] = NULL; |
| 86 | } |
| 87 | |
| 88 | return g_steal_pointer(&set); |
| 89 | } |
| 90 | |
| 91 | static GHashTable * |
| 92 | dbus_get_proxies(DBusVMState *self, GError **err) |
| 93 | { |
| 94 | g_autoptr(GHashTable) proxies = NULL; |
| 95 | g_autoptr(GHashTable) ids = NULL; |
| 96 | g_auto(GStrv) names = NULL; |
| 97 | Error *error = NULL; |
| 98 | size_t i; |
| 99 | |
| 100 | ids = get_id_list_set(self); |
| 101 | proxies = g_hash_table_new_full(g_str_hash, g_str_equal, |
| 102 | g_free, g_object_unref); |
| 103 | |
| 104 | names = qemu_dbus_get_queued_owners(self->bus, "org.qemu.VMState1", &error); |
| 105 | if (!names) { |
| 106 | g_set_error(err, G_IO_ERROR, G_IO_ERROR_FAILED, "%s", |
| 107 | error_get_pretty(error)); |
| 108 | error_free(error); |
| 109 | return NULL; |
| 110 | } |
| 111 | |
| 112 | for (i = 0; names[i]; i++) { |
| 113 | g_autoptr(GDBusProxy) proxy = NULL; |
| 114 | g_autoptr(GVariant) result = NULL; |
| 115 | g_autofree char *id = NULL; |
| 116 | size_t size; |
| 117 | |
| 118 | proxy = g_dbus_proxy_new_sync(self->bus, G_DBUS_PROXY_FLAGS_NONE, |
| 119 | (GDBusInterfaceInfo *) &vmstate1_interface_info, |
| 120 | names[i], |
| 121 | "/org/qemu/VMState1", |
| 122 | "org.qemu.VMState1", |
| 123 | NULL, err); |
| 124 | if (!proxy) { |
| 125 | return NULL; |
| 126 | } |
| 127 | |
| 128 | result = g_dbus_proxy_get_cached_property(proxy, "Id"); |
| 129 | if (!result) { |
| 130 | g_set_error_literal(err, G_IO_ERROR, G_IO_ERROR_FAILED, |
| 131 | "VMState Id property is missing."); |
| 132 | return NULL; |
| 133 | } |
| 134 | |
| 135 | id = g_variant_dup_string(result, &size); |
| 136 | if (ids && !g_hash_table_remove(ids, id)) { |
| 137 | g_clear_pointer(&id, g_free); |
| 138 | g_clear_object(&proxy); |
| 139 | continue; |
| 140 | } |
| 141 | if (size == 0 || size >= 256) { |
| 142 | g_set_error(err, G_IO_ERROR, G_IO_ERROR_FAILED, |
| 143 | "VMState Id '%s' is invalid.", id); |
| 144 | return NULL; |
| 145 | } |
| 146 | |
| 147 | if (!g_hash_table_insert(proxies, id, proxy)) { |
| 148 | g_set_error(err, G_IO_ERROR, G_IO_ERROR_FAILED, |
| 149 | "Duplicated VMState Id '%s'", id); |
| 150 | return NULL; |
| 151 | } |
| 152 | id = NULL; |
| 153 | proxy = NULL; |
| 154 | |
| 155 | g_clear_pointer(&result, g_variant_unref); |
| 156 | } |
| 157 | |
| 158 | if (ids) { |
| 159 | g_autofree char **left = NULL; |
| 160 | |
| 161 | left = (char **)g_hash_table_get_keys_as_array(ids, NULL); |
| 162 | if (*left) { |
| 163 | g_autofree char *leftids = g_strjoinv(",", left); |
| 164 | g_set_error(err, G_IO_ERROR, G_IO_ERROR_FAILED, |
| 165 | "Required VMState Id are missing: %s", leftids); |
| 166 | return NULL; |
| 167 | } |
| 168 | } |
| 169 | |
| 170 | return g_steal_pointer(&proxies); |
| 171 | } |
| 172 | |
| 173 | static int |
| 174 | dbus_load_state_proxy(GDBusProxy *proxy, const uint8_t *data, size_t size) |
| 175 | { |
| 176 | g_autoptr(GError) err = NULL; |
| 177 | g_autoptr(GVariant) result = NULL; |
| 178 | g_autoptr(GVariant) value = NULL; |
| 179 | |
| 180 | value = g_variant_new_fixed_array(G_VARIANT_TYPE_BYTE, |
| 181 | data, size, sizeof(char)); |
| 182 | result = g_dbus_proxy_call_sync(proxy, "Load", |
| 183 | g_variant_new("(@ay)", |
| 184 | g_steal_pointer(&value)), |
| 185 | G_DBUS_CALL_FLAGS_NO_AUTO_START, |
| 186 | -1, NULL, &err); |
| 187 | if (!result) { |
| 188 | error_report("%s: Failed to Load: %s", __func__, err->message); |
| 189 | return -1; |
| 190 | } |
| 191 | |
| 192 | return 0; |
| 193 | } |
| 194 | |
| 195 | static int dbus_vmstate_post_load(void *opaque, int version_id) |
| 196 | { |
| 197 | DBusVMState *self = DBUS_VMSTATE(opaque); |
| 198 | g_autoptr(GInputStream) m = NULL; |
| 199 | g_autoptr(GDataInputStream) s = NULL; |
| 200 | g_autoptr(GError) err = NULL; |
| 201 | g_autoptr(GHashTable) proxies = NULL; |
| 202 | uint32_t nelem; |
| 203 | |
| 204 | trace_dbus_vmstate_post_load(version_id); |
| 205 | |
| 206 | proxies = dbus_get_proxies(self, &err); |
| 207 | if (!proxies) { |
| 208 | error_report("%s: Failed to get proxies: %s", __func__, err->message); |
| 209 | return -1; |
| 210 | } |
| 211 | |
| 212 | m = g_memory_input_stream_new_from_data(self->data, self->data_size, NULL); |
| 213 | s = g_data_input_stream_new(m); |
| 214 | g_data_input_stream_set_byte_order(s, G_DATA_STREAM_BYTE_ORDER_BIG_ENDIAN); |
| 215 | |
| 216 | nelem = g_data_input_stream_read_uint32(s, NULL, &err); |
| 217 | if (err) { |
| 218 | goto error; |
| 219 | } |
| 220 | |
| 221 | while (nelem > 0) { |
| 222 | GDBusProxy *proxy = NULL; |
| 223 | uint32_t len; |
| 224 | gsize bytes_read, avail; |
| 225 | char id[256]; |
| 226 | |
| 227 | len = g_data_input_stream_read_uint32(s, NULL, &err); |
| 228 | if (err) { |
| 229 | goto error; |
| 230 | } |
| 231 | if (len >= 256) { |
| 232 | error_report("%s: Invalid DBus vmstate proxy name %u", |
| 233 | __func__, len); |
| 234 | return -1; |
| 235 | } |
| 236 | if (!g_input_stream_read_all(G_INPUT_STREAM(s), id, len, |
| 237 | &bytes_read, NULL, &err)) { |
| 238 | goto error; |
| 239 | } |
| 240 | g_return_val_if_fail(bytes_read == len, -1); |
| 241 | id[len] = 0; |
| 242 | |
| 243 | trace_dbus_vmstate_loading(id); |
| 244 | |
| 245 | proxy = g_hash_table_lookup(proxies, id); |
| 246 | if (!proxy) { |
| 247 | error_report("%s: Failed to find proxy Id '%s'", __func__, id); |
| 248 | return -1; |
| 249 | } |
| 250 | |
| 251 | len = g_data_input_stream_read_uint32(s, NULL, &err); |
| 252 | avail = g_buffered_input_stream_get_available( |
| 253 | G_BUFFERED_INPUT_STREAM(s)); |
| 254 | |
| 255 | if (len > DBUS_VMSTATE_SIZE_LIMIT || len > avail) { |
| 256 | error_report("%s: Invalid vmstate size: %u", __func__, len); |
| 257 | return -1; |
| 258 | } |
| 259 | |
| 260 | if (dbus_load_state_proxy(proxy, |
| 261 | g_buffered_input_stream_peek_buffer(G_BUFFERED_INPUT_STREAM(s), |
| 262 | NULL), |
| 263 | len) < 0) { |
| 264 | error_report("%s: Failed to restore Id '%s'", __func__, id); |
| 265 | return -1; |
| 266 | } |
| 267 | |
| 268 | if (!g_seekable_seek(G_SEEKABLE(s), len, G_SEEK_CUR, NULL, &err)) { |
| 269 | goto error; |
| 270 | } |
| 271 | |
| 272 | nelem -= 1; |
| 273 | } |
| 274 | |
| 275 | return 0; |
| 276 | |
| 277 | error: |
| 278 | error_report("%s: Failed to read from stream: %s", __func__, err->message); |
| 279 | return -1; |
| 280 | } |
| 281 | |
| 282 | static void |
| 283 | dbus_save_state_proxy(gpointer key, |
| 284 | gpointer value, |
| 285 | gpointer user_data) |
| 286 | { |
| 287 | GDataOutputStream *s = user_data; |
| 288 | const char *id = key; |
| 289 | GDBusProxy *proxy = value; |
| 290 | g_autoptr(GVariant) result = NULL; |
| 291 | g_autoptr(GVariant) child = NULL; |
| 292 | g_autoptr(GError) err = NULL; |
| 293 | const uint8_t *data; |
| 294 | gsize size; |
| 295 | |
| 296 | trace_dbus_vmstate_saving(id); |
| 297 | |
| 298 | result = g_dbus_proxy_call_sync(proxy, "Save", |
| 299 | NULL, G_DBUS_CALL_FLAGS_NO_AUTO_START, |
| 300 | -1, NULL, &err); |
| 301 | if (!result) { |
| 302 | error_report("%s: Failed to Save: %s", __func__, err->message); |
| 303 | return; |
| 304 | } |
| 305 | |
| 306 | child = g_variant_get_child_value(result, 0); |
| 307 | data = g_variant_get_fixed_array(child, &size, sizeof(char)); |
| 308 | if (!data) { |
| 309 | error_report("%s: Failed to Save: not a byte array", __func__); |
| 310 | return; |
| 311 | } |
| 312 | if (size > DBUS_VMSTATE_SIZE_LIMIT) { |
| 313 | error_report("%s: Too large vmstate data to save: %zu", |
| 314 | __func__, (size_t)size); |
| 315 | return; |
| 316 | } |
| 317 | |
| 318 | if (!g_data_output_stream_put_uint32(s, strlen(id), NULL, &err) || |
| 319 | !g_data_output_stream_put_string(s, id, NULL, &err) || |
| 320 | !g_data_output_stream_put_uint32(s, size, NULL, &err) || |
| 321 | !g_output_stream_write_all(G_OUTPUT_STREAM(s), |
| 322 | data, size, NULL, NULL, &err)) { |
| 323 | error_report("%s: Failed to write to stream: %s", |
| 324 | __func__, err->message); |
| 325 | } |
| 326 | } |
| 327 | |
| 328 | static int dbus_vmstate_pre_save(void *opaque) |
| 329 | { |
| 330 | DBusVMState *self = DBUS_VMSTATE(opaque); |
| 331 | g_autoptr(GOutputStream) m = NULL; |
| 332 | g_autoptr(GDataOutputStream) s = NULL; |
| 333 | g_autoptr(GHashTable) proxies = NULL; |
| 334 | g_autoptr(GError) err = NULL; |
| 335 | |
| 336 | trace_dbus_vmstate_pre_save(); |
| 337 | |
| 338 | proxies = dbus_get_proxies(self, &err); |
| 339 | if (!proxies) { |
| 340 | error_report("%s: Failed to get proxies: %s", __func__, err->message); |
| 341 | return -1; |
| 342 | } |
| 343 | |
| 344 | m = g_memory_output_stream_new_resizable(); |
| 345 | s = g_data_output_stream_new(m); |
| 346 | g_data_output_stream_set_byte_order(s, G_DATA_STREAM_BYTE_ORDER_BIG_ENDIAN); |
| 347 | |
| 348 | if (!g_data_output_stream_put_uint32(s, g_hash_table_size(proxies), |
| 349 | NULL, &err)) { |
| 350 | error_report("%s: Failed to write to stream: %s", |
| 351 | __func__, err->message); |
| 352 | return -1; |
| 353 | } |
| 354 | |
| 355 | g_hash_table_foreach(proxies, dbus_save_state_proxy, s); |
| 356 | |
| 357 | if (g_memory_output_stream_get_size(G_MEMORY_OUTPUT_STREAM(m)) |
| 358 | > UINT32_MAX) { |
| 359 | error_report("%s: DBus vmstate buffer is too large", __func__); |
| 360 | return -1; |
| 361 | } |
| 362 | |
| 363 | if (!g_output_stream_close(G_OUTPUT_STREAM(m), NULL, &err)) { |
| 364 | error_report("%s: Failed to close stream: %s", __func__, err->message); |
| 365 | return -1; |
| 366 | } |
| 367 | |
| 368 | g_free(self->data); |
| 369 | self->data_size = |
| 370 | g_memory_output_stream_get_size(G_MEMORY_OUTPUT_STREAM(m)); |
| 371 | self->data = |
| 372 | g_memory_output_stream_steal_data(G_MEMORY_OUTPUT_STREAM(m)); |
| 373 | |
| 374 | return 0; |
| 375 | } |
| 376 | |
| 377 | static const VMStateDescription dbus_vmstate = { |
| 378 | .name = TYPE_DBUS_VMSTATE, |
| 379 | .version_id = 0, |
| 380 | .pre_save = dbus_vmstate_pre_save, |
| 381 | .post_load = dbus_vmstate_post_load, |
| 382 | .fields = (VMStateField[]) { |
| 383 | VMSTATE_UINT32(data_size, DBusVMState), |
| 384 | VMSTATE_VBUFFER_ALLOC_UINT32(data, DBusVMState, 0, 0, data_size), |
| 385 | VMSTATE_END_OF_LIST() |
| 386 | } |
| 387 | }; |
| 388 | |
| 389 | static void |
| 390 | dbus_vmstate_complete(UserCreatable *uc, Error **errp) |
| 391 | { |
| 392 | DBusVMState *self = DBUS_VMSTATE(uc); |
| 393 | g_autoptr(GError) err = NULL; |
| 394 | |
| 395 | if (!object_resolve_path_type("", TYPE_DBUS_VMSTATE, NULL)) { |
| 396 | error_setg(errp, "There is already an instance of %s", |
| 397 | TYPE_DBUS_VMSTATE); |
| 398 | return; |
| 399 | } |
| 400 | |
| 401 | if (!self->dbus_addr) { |
| 402 | error_setg(errp, QERR_MISSING_PARAMETER, "addr"); |
| 403 | return; |
| 404 | } |
| 405 | |
| 406 | self->bus = g_dbus_connection_new_for_address_sync(self->dbus_addr, |
| 407 | G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_CLIENT | |
| 408 | G_DBUS_CONNECTION_FLAGS_MESSAGE_BUS_CONNECTION, |
| 409 | NULL, NULL, &err); |
| 410 | if (err) { |
| 411 | error_setg(errp, "failed to connect to DBus: '%s'", err->message); |
| 412 | return; |
| 413 | } |
| 414 | |
| 415 | if (vmstate_register(VMSTATE_IF(self), -1, &dbus_vmstate, self) < 0) { |
| 416 | error_setg(errp, "Failed to register vmstate"); |
| 417 | } |
| 418 | } |
| 419 | |
| 420 | static void |
| 421 | dbus_vmstate_finalize(Object *o) |
| 422 | { |
| 423 | DBusVMState *self = DBUS_VMSTATE(o); |
| 424 | |
| 425 | vmstate_unregister(VMSTATE_IF(self), &dbus_vmstate, self); |
| 426 | |
| 427 | g_clear_object(&self->bus); |
| 428 | g_free(self->dbus_addr); |
| 429 | g_free(self->id_list); |
| 430 | g_free(self->data); |
| 431 | } |
| 432 | |
| 433 | static char * |
| 434 | get_dbus_addr(Object *o, Error **errp) |
| 435 | { |
| 436 | DBusVMState *self = DBUS_VMSTATE(o); |
| 437 | |
| 438 | return g_strdup(self->dbus_addr); |
| 439 | } |
| 440 | |
| 441 | static void |
| 442 | set_dbus_addr(Object *o, const char *str, Error **errp) |
| 443 | { |
| 444 | DBusVMState *self = DBUS_VMSTATE(o); |
| 445 | |
| 446 | g_free(self->dbus_addr); |
| 447 | self->dbus_addr = g_strdup(str); |
| 448 | } |
| 449 | |
| 450 | static char * |
| 451 | get_id_list(Object *o, Error **errp) |
| 452 | { |
| 453 | DBusVMState *self = DBUS_VMSTATE(o); |
| 454 | |
| 455 | return g_strdup(self->id_list); |
| 456 | } |
| 457 | |
| 458 | static void |
| 459 | set_id_list(Object *o, const char *str, Error **errp) |
| 460 | { |
| 461 | DBusVMState *self = DBUS_VMSTATE(o); |
| 462 | |
| 463 | g_free(self->id_list); |
| 464 | self->id_list = g_strdup(str); |
| 465 | } |
| 466 | |
| 467 | static char * |
| 468 | dbus_vmstate_get_id(VMStateIf *vmif) |
| 469 | { |
| 470 | return g_strdup(TYPE_DBUS_VMSTATE); |
| 471 | } |
| 472 | |
| 473 | static void |
| 474 | dbus_vmstate_class_init(ObjectClass *oc, void *data) |
| 475 | { |
| 476 | UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc); |
| 477 | VMStateIfClass *vc = VMSTATE_IF_CLASS(oc); |
| 478 | |
| 479 | ucc->complete = dbus_vmstate_complete; |
| 480 | vc->get_id = dbus_vmstate_get_id; |
| 481 | |
| 482 | object_class_property_add_str(oc, "addr", |
| 483 | get_dbus_addr, set_dbus_addr, |
| 484 | &error_abort); |
| 485 | object_class_property_add_str(oc, "id-list", |
| 486 | get_id_list, set_id_list, |
| 487 | &error_abort); |
| 488 | } |
| 489 | |
| 490 | static const TypeInfo dbus_vmstate_info = { |
| 491 | .name = TYPE_DBUS_VMSTATE, |
| 492 | .parent = TYPE_OBJECT, |
| 493 | .instance_size = sizeof(DBusVMState), |
| 494 | .instance_finalize = dbus_vmstate_finalize, |
| 495 | .class_size = sizeof(DBusVMStateClass), |
| 496 | .class_init = dbus_vmstate_class_init, |
| 497 | .interfaces = (InterfaceInfo[]) { |
| 498 | { TYPE_USER_CREATABLE }, |
| 499 | { TYPE_VMSTATE_IF }, |
| 500 | { } |
| 501 | } |
| 502 | }; |
| 503 | |
| 504 | static void |
| 505 | register_types(void) |
| 506 | { |
| 507 | type_register_static(&dbus_vmstate_info); |
| 508 | } |
| 509 | |
| 510 | type_init(register_types); |