1 /* 2 * Copyright (c) 2018 Citrix Systems Inc. 3 * 4 * This work is licensed under the terms of the GNU GPL, version 2 or later. 5 * See the COPYING file in the top-level directory. 6 */ 7 8 #include "qemu/osdep.h" 9 #include "qemu/cutils.h" 10 #include "qemu/main-loop.h" 11 #include "qemu/module.h" 12 #include "qemu/option.h" 13 #include "qapi/error.h" 14 #include "qapi/qapi-commands-block-core.h" 15 #include "qapi/qapi-commands-qom.h" 16 #include "qapi/qapi-visit-block-core.h" 17 #include "qapi/qobject-input-visitor.h" 18 #include "qapi/visitor.h" 19 #include "qapi/qmp/qdict.h" 20 #include "qapi/qmp/qstring.h" 21 #include "qom/object_interfaces.h" 22 #include "hw/xen/xen_common.h" 23 #include "hw/block/xen_blkif.h" 24 #include "hw/qdev-properties.h" 25 #include "hw/xen/xen-block.h" 26 #include "hw/xen/xen-backend.h" 27 #include "sysemu/blockdev.h" 28 #include "sysemu/block-backend.h" 29 #include "sysemu/iothread.h" 30 #include "dataplane/xen-block.h" 31 #include "trace.h" 32 33 static char *xen_block_get_name(XenDevice *xendev, Error **errp) 34 { 35 XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev); 36 XenBlockVdev *vdev = &blockdev->props.vdev; 37 38 return g_strdup_printf("%lu", vdev->number); 39 } 40 41 static void xen_block_disconnect(XenDevice *xendev, Error **errp) 42 { 43 XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev); 44 const char *type = object_get_typename(OBJECT(blockdev)); 45 XenBlockVdev *vdev = &blockdev->props.vdev; 46 47 trace_xen_block_disconnect(type, vdev->disk, vdev->partition); 48 49 xen_block_dataplane_stop(blockdev->dataplane); 50 } 51 52 static void xen_block_connect(XenDevice *xendev, Error **errp) 53 { 54 XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev); 55 const char *type = object_get_typename(OBJECT(blockdev)); 56 XenBlockVdev *vdev = &blockdev->props.vdev; 57 BlockConf *conf = &blockdev->props.conf; 58 unsigned int feature_large_sector_size; 59 unsigned int order, nr_ring_ref, *ring_ref, event_channel, protocol; 60 char *str; 61 62 trace_xen_block_connect(type, vdev->disk, vdev->partition); 63 64 if (xen_device_frontend_scanf(xendev, "feature-large-sector-size", "%u", 65 &feature_large_sector_size) != 1) { 66 feature_large_sector_size = 0; 67 } 68 69 if (feature_large_sector_size != 1 && 70 conf->logical_block_size != XEN_BLKIF_SECTOR_SIZE) { 71 error_setg(errp, "logical_block_size != %u not supported by frontend", 72 XEN_BLKIF_SECTOR_SIZE); 73 return; 74 } 75 76 if (xen_device_frontend_scanf(xendev, "ring-page-order", "%u", 77 &order) != 1) { 78 nr_ring_ref = 1; 79 ring_ref = g_new(unsigned int, nr_ring_ref); 80 81 if (xen_device_frontend_scanf(xendev, "ring-ref", "%u", 82 &ring_ref[0]) != 1) { 83 error_setg(errp, "failed to read ring-ref"); 84 g_free(ring_ref); 85 return; 86 } 87 } else if (order <= blockdev->props.max_ring_page_order) { 88 unsigned int i; 89 90 nr_ring_ref = 1 << order; 91 ring_ref = g_new(unsigned int, nr_ring_ref); 92 93 for (i = 0; i < nr_ring_ref; i++) { 94 const char *key = g_strdup_printf("ring-ref%u", i); 95 96 if (xen_device_frontend_scanf(xendev, key, "%u", 97 &ring_ref[i]) != 1) { 98 error_setg(errp, "failed to read %s", key); 99 g_free((gpointer)key); 100 g_free(ring_ref); 101 return; 102 } 103 104 g_free((gpointer)key); 105 } 106 } else { 107 error_setg(errp, "invalid ring-page-order (%d)", order); 108 return; 109 } 110 111 if (xen_device_frontend_scanf(xendev, "event-channel", "%u", 112 &event_channel) != 1) { 113 error_setg(errp, "failed to read event-channel"); 114 g_free(ring_ref); 115 return; 116 } 117 118 if (xen_device_frontend_scanf(xendev, "protocol", "%ms", 119 &str) != 1) { 120 protocol = BLKIF_PROTOCOL_NATIVE; 121 } else { 122 if (strcmp(str, XEN_IO_PROTO_ABI_X86_32) == 0) { 123 protocol = BLKIF_PROTOCOL_X86_32; 124 } else if (strcmp(str, XEN_IO_PROTO_ABI_X86_64) == 0) { 125 protocol = BLKIF_PROTOCOL_X86_64; 126 } else { 127 protocol = BLKIF_PROTOCOL_NATIVE; 128 } 129 130 free(str); 131 } 132 133 xen_block_dataplane_start(blockdev->dataplane, ring_ref, nr_ring_ref, 134 event_channel, protocol, errp); 135 136 g_free(ring_ref); 137 } 138 139 static void xen_block_unrealize(XenDevice *xendev) 140 { 141 XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev); 142 XenBlockDeviceClass *blockdev_class = 143 XEN_BLOCK_DEVICE_GET_CLASS(xendev); 144 const char *type = object_get_typename(OBJECT(blockdev)); 145 XenBlockVdev *vdev = &blockdev->props.vdev; 146 147 if (vdev->type == XEN_BLOCK_VDEV_TYPE_INVALID) { 148 return; 149 } 150 151 trace_xen_block_unrealize(type, vdev->disk, vdev->partition); 152 153 /* Disconnect from the frontend in case this has not already happened */ 154 xen_block_disconnect(xendev, NULL); 155 156 xen_block_dataplane_destroy(blockdev->dataplane); 157 blockdev->dataplane = NULL; 158 159 if (blockdev_class->unrealize) { 160 blockdev_class->unrealize(blockdev); 161 } 162 } 163 164 static void xen_block_set_size(XenBlockDevice *blockdev) 165 { 166 const char *type = object_get_typename(OBJECT(blockdev)); 167 XenBlockVdev *vdev = &blockdev->props.vdev; 168 BlockConf *conf = &blockdev->props.conf; 169 int64_t sectors = blk_getlength(conf->blk) / conf->logical_block_size; 170 XenDevice *xendev = XEN_DEVICE(blockdev); 171 172 trace_xen_block_size(type, vdev->disk, vdev->partition, sectors); 173 174 xen_device_backend_printf(xendev, "sectors", "%"PRIi64, sectors); 175 } 176 177 static void xen_block_resize_cb(void *opaque) 178 { 179 XenBlockDevice *blockdev = opaque; 180 XenDevice *xendev = XEN_DEVICE(blockdev); 181 enum xenbus_state state = xen_device_backend_get_state(xendev); 182 183 xen_block_set_size(blockdev); 184 185 /* 186 * Mimic the behaviour of Linux xen-blkback and re-write the state 187 * to trigger the frontend watch. 188 */ 189 xen_device_backend_printf(xendev, "state", "%u", state); 190 } 191 192 static const BlockDevOps xen_block_dev_ops = { 193 .resize_cb = xen_block_resize_cb, 194 }; 195 196 static void xen_block_realize(XenDevice *xendev, Error **errp) 197 { 198 ERRP_GUARD(); 199 XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev); 200 XenBlockDeviceClass *blockdev_class = 201 XEN_BLOCK_DEVICE_GET_CLASS(xendev); 202 const char *type = object_get_typename(OBJECT(blockdev)); 203 XenBlockVdev *vdev = &blockdev->props.vdev; 204 BlockConf *conf = &blockdev->props.conf; 205 BlockBackend *blk = conf->blk; 206 207 if (vdev->type == XEN_BLOCK_VDEV_TYPE_INVALID) { 208 error_setg(errp, "vdev property not set"); 209 return; 210 } 211 212 trace_xen_block_realize(type, vdev->disk, vdev->partition); 213 214 if (blockdev_class->realize) { 215 blockdev_class->realize(blockdev, errp); 216 if (*errp) { 217 return; 218 } 219 } 220 221 /* 222 * The blkif protocol does not deal with removable media, so it must 223 * always be present, even for CDRom devices. 224 */ 225 assert(blk); 226 if (!blk_is_inserted(blk)) { 227 error_setg(errp, "device needs media, but drive is empty"); 228 return; 229 } 230 231 if (!blkconf_apply_backend_options(conf, blockdev->info & VDISK_READONLY, 232 true, errp)) { 233 return; 234 } 235 236 if (!(blockdev->info & VDISK_CDROM) && 237 !blkconf_geometry(conf, NULL, 65535, 255, 255, errp)) { 238 return; 239 } 240 241 if (!blkconf_blocksizes(conf, errp)) { 242 return; 243 } 244 245 blk_set_dev_ops(blk, &xen_block_dev_ops, blockdev); 246 blk_set_guest_block_size(blk, conf->logical_block_size); 247 248 if (conf->discard_granularity == -1) { 249 conf->discard_granularity = conf->physical_block_size; 250 } 251 252 if (blk_get_flags(blk) & BDRV_O_UNMAP) { 253 xen_device_backend_printf(xendev, "feature-discard", "%u", 1); 254 xen_device_backend_printf(xendev, "discard-granularity", "%u", 255 conf->discard_granularity); 256 } 257 258 xen_device_backend_printf(xendev, "feature-flush-cache", "%u", 1); 259 xen_device_backend_printf(xendev, "max-ring-page-order", "%u", 260 blockdev->props.max_ring_page_order); 261 xen_device_backend_printf(xendev, "info", "%u", blockdev->info); 262 263 xen_device_frontend_printf(xendev, "virtual-device", "%lu", 264 vdev->number); 265 xen_device_frontend_printf(xendev, "device-type", "%s", 266 blockdev->device_type); 267 268 xen_device_backend_printf(xendev, "sector-size", "%u", 269 conf->logical_block_size); 270 271 xen_block_set_size(blockdev); 272 273 blockdev->dataplane = 274 xen_block_dataplane_create(xendev, blk, conf->logical_block_size, 275 blockdev->props.iothread); 276 } 277 278 static void xen_block_frontend_changed(XenDevice *xendev, 279 enum xenbus_state frontend_state, 280 Error **errp) 281 { 282 ERRP_GUARD(); 283 enum xenbus_state backend_state = xen_device_backend_get_state(xendev); 284 285 switch (frontend_state) { 286 case XenbusStateInitialised: 287 case XenbusStateConnected: 288 if (backend_state == XenbusStateConnected) { 289 break; 290 } 291 292 xen_block_disconnect(xendev, errp); 293 if (*errp) { 294 break; 295 } 296 297 xen_block_connect(xendev, errp); 298 if (*errp) { 299 break; 300 } 301 302 xen_device_backend_set_state(xendev, XenbusStateConnected); 303 break; 304 305 case XenbusStateClosing: 306 xen_device_backend_set_state(xendev, XenbusStateClosing); 307 break; 308 309 case XenbusStateClosed: 310 case XenbusStateUnknown: 311 xen_block_disconnect(xendev, errp); 312 if (*errp) { 313 break; 314 } 315 316 xen_device_backend_set_state(xendev, XenbusStateClosed); 317 break; 318 319 default: 320 break; 321 } 322 } 323 324 static char *disk_to_vbd_name(unsigned int disk) 325 { 326 char *name, *prefix = (disk >= 26) ? 327 disk_to_vbd_name((disk / 26) - 1) : g_strdup(""); 328 329 name = g_strdup_printf("%s%c", prefix, 'a' + disk % 26); 330 g_free(prefix); 331 332 return name; 333 } 334 335 static void xen_block_get_vdev(Object *obj, Visitor *v, const char *name, 336 void *opaque, Error **errp) 337 { 338 DeviceState *dev = DEVICE(obj); 339 Property *prop = opaque; 340 XenBlockVdev *vdev = qdev_get_prop_ptr(dev, prop); 341 char *str; 342 343 switch (vdev->type) { 344 case XEN_BLOCK_VDEV_TYPE_DP: 345 str = g_strdup_printf("d%lup%lu", vdev->disk, vdev->partition); 346 break; 347 348 case XEN_BLOCK_VDEV_TYPE_XVD: 349 case XEN_BLOCK_VDEV_TYPE_HD: 350 case XEN_BLOCK_VDEV_TYPE_SD: { 351 char *name = disk_to_vbd_name(vdev->disk); 352 353 str = g_strdup_printf("%s%s%lu", 354 (vdev->type == XEN_BLOCK_VDEV_TYPE_XVD) ? 355 "xvd" : 356 (vdev->type == XEN_BLOCK_VDEV_TYPE_HD) ? 357 "hd" : 358 "sd", 359 name, vdev->partition); 360 g_free(name); 361 break; 362 } 363 default: 364 error_setg(errp, "invalid vdev type"); 365 return; 366 } 367 368 visit_type_str(v, name, &str, errp); 369 g_free(str); 370 } 371 372 static int vbd_name_to_disk(const char *name, const char **endp, 373 unsigned long *disk) 374 { 375 unsigned int n = 0; 376 377 while (*name != '\0') { 378 if (!g_ascii_isalpha(*name) || !g_ascii_islower(*name)) { 379 break; 380 } 381 382 n *= 26; 383 n += *name++ - 'a' + 1; 384 } 385 *endp = name; 386 387 if (!n) { 388 return -1; 389 } 390 391 *disk = n - 1; 392 393 return 0; 394 } 395 396 static void xen_block_set_vdev(Object *obj, Visitor *v, const char *name, 397 void *opaque, Error **errp) 398 { 399 DeviceState *dev = DEVICE(obj); 400 Property *prop = opaque; 401 XenBlockVdev *vdev = qdev_get_prop_ptr(dev, prop); 402 char *str, *p; 403 const char *end; 404 405 if (dev->realized) { 406 qdev_prop_set_after_realize(dev, name, errp); 407 return; 408 } 409 410 if (!visit_type_str(v, name, &str, errp)) { 411 return; 412 } 413 414 p = strchr(str, 'd'); 415 if (!p) { 416 goto invalid; 417 } 418 419 *p++ = '\0'; 420 if (*str == '\0') { 421 vdev->type = XEN_BLOCK_VDEV_TYPE_DP; 422 } else if (strcmp(str, "xv") == 0) { 423 vdev->type = XEN_BLOCK_VDEV_TYPE_XVD; 424 } else if (strcmp(str, "h") == 0) { 425 vdev->type = XEN_BLOCK_VDEV_TYPE_HD; 426 } else if (strcmp(str, "s") == 0) { 427 vdev->type = XEN_BLOCK_VDEV_TYPE_SD; 428 } else { 429 goto invalid; 430 } 431 432 if (vdev->type == XEN_BLOCK_VDEV_TYPE_DP) { 433 if (qemu_strtoul(p, &end, 10, &vdev->disk)) { 434 goto invalid; 435 } 436 437 if (*end == 'p') { 438 if (*(++end) == '\0') { 439 goto invalid; 440 } 441 } 442 } else { 443 if (vbd_name_to_disk(p, &end, &vdev->disk)) { 444 goto invalid; 445 } 446 } 447 448 if (*end != '\0') { 449 p = (char *)end; 450 451 if (qemu_strtoul(p, &end, 10, &vdev->partition)) { 452 goto invalid; 453 } 454 455 if (*end != '\0') { 456 goto invalid; 457 } 458 } else { 459 vdev->partition = 0; 460 } 461 462 switch (vdev->type) { 463 case XEN_BLOCK_VDEV_TYPE_DP: 464 case XEN_BLOCK_VDEV_TYPE_XVD: 465 if (vdev->disk < (1 << 4) && vdev->partition < (1 << 4)) { 466 vdev->number = (202 << 8) | (vdev->disk << 4) | 467 vdev->partition; 468 } else if (vdev->disk < (1 << 20) && vdev->partition < (1 << 8)) { 469 vdev->number = (1 << 28) | (vdev->disk << 8) | 470 vdev->partition; 471 } else { 472 goto invalid; 473 } 474 break; 475 476 case XEN_BLOCK_VDEV_TYPE_HD: 477 if ((vdev->disk == 0 || vdev->disk == 1) && 478 vdev->partition < (1 << 6)) { 479 vdev->number = (3 << 8) | (vdev->disk << 6) | vdev->partition; 480 } else if ((vdev->disk == 2 || vdev->disk == 3) && 481 vdev->partition < (1 << 6)) { 482 vdev->number = (22 << 8) | ((vdev->disk - 2) << 6) | 483 vdev->partition; 484 } else { 485 goto invalid; 486 } 487 break; 488 489 case XEN_BLOCK_VDEV_TYPE_SD: 490 if (vdev->disk < (1 << 4) && vdev->partition < (1 << 4)) { 491 vdev->number = (8 << 8) | (vdev->disk << 4) | vdev->partition; 492 } else { 493 goto invalid; 494 } 495 break; 496 497 default: 498 goto invalid; 499 } 500 501 g_free(str); 502 return; 503 504 invalid: 505 error_setg(errp, "invalid virtual disk specifier"); 506 507 vdev->type = XEN_BLOCK_VDEV_TYPE_INVALID; 508 g_free(str); 509 } 510 511 /* 512 * This property deals with 'vdev' names adhering to the Xen VBD naming 513 * scheme described in: 514 * 515 * https://xenbits.xen.org/docs/unstable/man/xen-vbd-interface.7.html 516 */ 517 const PropertyInfo xen_block_prop_vdev = { 518 .name = "str", 519 .description = "Virtual Disk specifier: d*p*/xvd*/hd*/sd*", 520 .get = xen_block_get_vdev, 521 .set = xen_block_set_vdev, 522 }; 523 524 static Property xen_block_props[] = { 525 DEFINE_PROP("vdev", XenBlockDevice, props.vdev, 526 xen_block_prop_vdev, XenBlockVdev), 527 DEFINE_BLOCK_PROPERTIES(XenBlockDevice, props.conf), 528 DEFINE_PROP_UINT32("max-ring-page-order", XenBlockDevice, 529 props.max_ring_page_order, 4), 530 DEFINE_PROP_LINK("iothread", XenBlockDevice, props.iothread, 531 TYPE_IOTHREAD, IOThread *), 532 DEFINE_PROP_END_OF_LIST() 533 }; 534 535 static void xen_block_class_init(ObjectClass *class, void *data) 536 { 537 DeviceClass *dev_class = DEVICE_CLASS(class); 538 XenDeviceClass *xendev_class = XEN_DEVICE_CLASS(class); 539 540 xendev_class->backend = "qdisk"; 541 xendev_class->device = "vbd"; 542 xendev_class->get_name = xen_block_get_name; 543 xendev_class->realize = xen_block_realize; 544 xendev_class->frontend_changed = xen_block_frontend_changed; 545 xendev_class->unrealize = xen_block_unrealize; 546 547 device_class_set_props(dev_class, xen_block_props); 548 } 549 550 static const TypeInfo xen_block_type_info = { 551 .name = TYPE_XEN_BLOCK_DEVICE, 552 .parent = TYPE_XEN_DEVICE, 553 .instance_size = sizeof(XenBlockDevice), 554 .abstract = true, 555 .class_size = sizeof(XenBlockDeviceClass), 556 .class_init = xen_block_class_init, 557 }; 558 559 static void xen_disk_unrealize(XenBlockDevice *blockdev) 560 { 561 trace_xen_disk_unrealize(); 562 } 563 564 static void xen_disk_realize(XenBlockDevice *blockdev, Error **errp) 565 { 566 BlockConf *conf = &blockdev->props.conf; 567 568 trace_xen_disk_realize(); 569 570 blockdev->device_type = "disk"; 571 572 if (!conf->blk) { 573 error_setg(errp, "drive property not set"); 574 return; 575 } 576 577 blockdev->info = blk_is_read_only(conf->blk) ? VDISK_READONLY : 0; 578 } 579 580 static void xen_disk_class_init(ObjectClass *class, void *data) 581 { 582 DeviceClass *dev_class = DEVICE_CLASS(class); 583 XenBlockDeviceClass *blockdev_class = XEN_BLOCK_DEVICE_CLASS(class); 584 585 blockdev_class->realize = xen_disk_realize; 586 blockdev_class->unrealize = xen_disk_unrealize; 587 588 dev_class->desc = "Xen Disk Device"; 589 } 590 591 static const TypeInfo xen_disk_type_info = { 592 .name = TYPE_XEN_DISK_DEVICE, 593 .parent = TYPE_XEN_BLOCK_DEVICE, 594 .instance_size = sizeof(XenDiskDevice), 595 .class_init = xen_disk_class_init, 596 }; 597 598 static void xen_cdrom_unrealize(XenBlockDevice *blockdev) 599 { 600 trace_xen_cdrom_unrealize(); 601 } 602 603 static void xen_cdrom_realize(XenBlockDevice *blockdev, Error **errp) 604 { 605 BlockConf *conf = &blockdev->props.conf; 606 607 trace_xen_cdrom_realize(); 608 609 blockdev->device_type = "cdrom"; 610 611 if (!conf->blk) { 612 int rc; 613 614 /* Set up an empty drive */ 615 conf->blk = blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL); 616 617 rc = blk_attach_dev(conf->blk, DEVICE(blockdev)); 618 if (!rc) { 619 error_setg_errno(errp, -rc, "failed to create drive"); 620 return; 621 } 622 } 623 624 blockdev->info = VDISK_READONLY | VDISK_CDROM; 625 } 626 627 static void xen_cdrom_class_init(ObjectClass *class, void *data) 628 { 629 DeviceClass *dev_class = DEVICE_CLASS(class); 630 XenBlockDeviceClass *blockdev_class = XEN_BLOCK_DEVICE_CLASS(class); 631 632 blockdev_class->realize = xen_cdrom_realize; 633 blockdev_class->unrealize = xen_cdrom_unrealize; 634 635 dev_class->desc = "Xen CD-ROM Device"; 636 } 637 638 static const TypeInfo xen_cdrom_type_info = { 639 .name = TYPE_XEN_CDROM_DEVICE, 640 .parent = TYPE_XEN_BLOCK_DEVICE, 641 .instance_size = sizeof(XenCDRomDevice), 642 .class_init = xen_cdrom_class_init, 643 }; 644 645 static void xen_block_register_types(void) 646 { 647 type_register_static(&xen_block_type_info); 648 type_register_static(&xen_disk_type_info); 649 type_register_static(&xen_cdrom_type_info); 650 } 651 652 type_init(xen_block_register_types) 653 654 static void xen_block_blockdev_del(const char *node_name, Error **errp) 655 { 656 trace_xen_block_blockdev_del(node_name); 657 658 qmp_blockdev_del(node_name, errp); 659 } 660 661 static char *xen_block_blockdev_add(const char *id, QDict *qdict, 662 Error **errp) 663 { 664 ERRP_GUARD(); 665 const char *driver = qdict_get_try_str(qdict, "driver"); 666 BlockdevOptions *options = NULL; 667 char *node_name; 668 Visitor *v; 669 670 if (!driver) { 671 error_setg(errp, "no 'driver' parameter"); 672 return NULL; 673 } 674 675 node_name = g_strdup_printf("%s-%s", id, driver); 676 qdict_put_str(qdict, "node-name", node_name); 677 678 trace_xen_block_blockdev_add(node_name); 679 680 v = qobject_input_visitor_new(QOBJECT(qdict)); 681 visit_type_BlockdevOptions(v, NULL, &options, errp); 682 visit_free(v); 683 if (!options) { 684 goto fail; 685 } 686 687 qmp_blockdev_add(options, errp); 688 689 if (*errp) { 690 goto fail; 691 } 692 693 qapi_free_BlockdevOptions(options); 694 695 return node_name; 696 697 fail: 698 if (options) { 699 qapi_free_BlockdevOptions(options); 700 } 701 g_free(node_name); 702 703 return NULL; 704 } 705 706 static void xen_block_drive_destroy(XenBlockDrive *drive, Error **errp) 707 { 708 ERRP_GUARD(); 709 char *node_name = drive->node_name; 710 711 if (node_name) { 712 xen_block_blockdev_del(node_name, errp); 713 if (*errp) { 714 return; 715 } 716 g_free(node_name); 717 drive->node_name = NULL; 718 } 719 g_free(drive->id); 720 g_free(drive); 721 } 722 723 static XenBlockDrive *xen_block_drive_create(const char *id, 724 const char *device_type, 725 QDict *opts, Error **errp) 726 { 727 ERRP_GUARD(); 728 const char *params = qdict_get_try_str(opts, "params"); 729 const char *mode = qdict_get_try_str(opts, "mode"); 730 const char *direct_io_safe = qdict_get_try_str(opts, "direct-io-safe"); 731 const char *discard_enable = qdict_get_try_str(opts, "discard-enable"); 732 char *driver = NULL; 733 char *filename = NULL; 734 XenBlockDrive *drive = NULL; 735 QDict *file_layer; 736 QDict *driver_layer; 737 738 if (params) { 739 char **v = g_strsplit(params, ":", 2); 740 741 if (v[1] == NULL) { 742 filename = g_strdup(v[0]); 743 driver = g_strdup("raw"); 744 } else { 745 if (strcmp(v[0], "aio") == 0) { 746 driver = g_strdup("raw"); 747 } else if (strcmp(v[0], "vhd") == 0) { 748 driver = g_strdup("vpc"); 749 } else { 750 driver = g_strdup(v[0]); 751 } 752 filename = g_strdup(v[1]); 753 } 754 755 g_strfreev(v); 756 } else { 757 error_setg(errp, "no params"); 758 goto done; 759 } 760 761 assert(filename); 762 assert(driver); 763 764 drive = g_new0(XenBlockDrive, 1); 765 drive->id = g_strdup(id); 766 767 file_layer = qdict_new(); 768 driver_layer = qdict_new(); 769 770 qdict_put_str(file_layer, "driver", "file"); 771 qdict_put_str(file_layer, "filename", filename); 772 g_free(filename); 773 774 if (mode && *mode != 'w') { 775 qdict_put_bool(file_layer, "read-only", true); 776 } 777 778 if (direct_io_safe) { 779 unsigned long value; 780 781 if (!qemu_strtoul(direct_io_safe, NULL, 2, &value) && !!value) { 782 QDict *cache_qdict = qdict_new(); 783 784 qdict_put_bool(cache_qdict, "direct", true); 785 qdict_put(file_layer, "cache", cache_qdict); 786 787 qdict_put_str(file_layer, "aio", "native"); 788 } 789 } 790 791 if (discard_enable) { 792 unsigned long value; 793 794 if (!qemu_strtoul(discard_enable, NULL, 2, &value) && !!value) { 795 qdict_put_str(file_layer, "discard", "unmap"); 796 qdict_put_str(driver_layer, "discard", "unmap"); 797 } 798 } 799 800 /* 801 * It is necessary to turn file locking off as an emulated device 802 * may have already opened the same image file. 803 */ 804 qdict_put_str(file_layer, "locking", "off"); 805 806 qdict_put_str(driver_layer, "driver", driver); 807 g_free(driver); 808 809 qdict_put(driver_layer, "file", file_layer); 810 811 g_assert(!drive->node_name); 812 drive->node_name = xen_block_blockdev_add(drive->id, driver_layer, 813 errp); 814 815 qobject_unref(driver_layer); 816 817 done: 818 if (*errp) { 819 xen_block_drive_destroy(drive, NULL); 820 return NULL; 821 } 822 823 return drive; 824 } 825 826 static const char *xen_block_drive_get_node_name(XenBlockDrive *drive) 827 { 828 return drive->node_name ? drive->node_name : ""; 829 } 830 831 static void xen_block_iothread_destroy(XenBlockIOThread *iothread, 832 Error **errp) 833 { 834 qmp_object_del(iothread->id, errp); 835 836 g_free(iothread->id); 837 g_free(iothread); 838 } 839 840 static XenBlockIOThread *xen_block_iothread_create(const char *id, 841 Error **errp) 842 { 843 ERRP_GUARD(); 844 XenBlockIOThread *iothread = g_new(XenBlockIOThread, 1); 845 QDict *opts; 846 QObject *ret_data = NULL; 847 848 iothread->id = g_strdup(id); 849 850 opts = qdict_new(); 851 qdict_put_str(opts, "qom-type", TYPE_IOTHREAD); 852 qdict_put_str(opts, "id", id); 853 qmp_object_add(opts, &ret_data, errp); 854 qobject_unref(opts); 855 qobject_unref(ret_data); 856 857 if (*errp) { 858 g_free(iothread->id); 859 g_free(iothread); 860 return NULL; 861 } 862 863 return iothread; 864 } 865 866 static void xen_block_device_create(XenBackendInstance *backend, 867 QDict *opts, Error **errp) 868 { 869 ERRP_GUARD(); 870 XenBus *xenbus = xen_backend_get_bus(backend); 871 const char *name = xen_backend_get_name(backend); 872 unsigned long number; 873 const char *vdev, *device_type; 874 XenBlockDrive *drive = NULL; 875 XenBlockIOThread *iothread = NULL; 876 XenDevice *xendev = NULL; 877 const char *type; 878 XenBlockDevice *blockdev; 879 880 if (qemu_strtoul(name, NULL, 10, &number)) { 881 error_setg(errp, "failed to parse name '%s'", name); 882 goto fail; 883 } 884 885 trace_xen_block_device_create(number); 886 887 vdev = qdict_get_try_str(opts, "dev"); 888 if (!vdev) { 889 error_setg(errp, "no dev parameter"); 890 goto fail; 891 } 892 893 device_type = qdict_get_try_str(opts, "device-type"); 894 if (!device_type) { 895 error_setg(errp, "no device-type parameter"); 896 goto fail; 897 } 898 899 if (!strcmp(device_type, "disk")) { 900 type = TYPE_XEN_DISK_DEVICE; 901 } else if (!strcmp(device_type, "cdrom")) { 902 type = TYPE_XEN_CDROM_DEVICE; 903 } else { 904 error_setg(errp, "invalid device-type parameter '%s'", device_type); 905 goto fail; 906 } 907 908 drive = xen_block_drive_create(vdev, device_type, opts, errp); 909 if (!drive) { 910 error_prepend(errp, "failed to create drive: "); 911 goto fail; 912 } 913 914 iothread = xen_block_iothread_create(vdev, errp); 915 if (*errp) { 916 error_prepend(errp, "failed to create iothread: "); 917 goto fail; 918 } 919 920 xendev = XEN_DEVICE(qdev_new(type)); 921 blockdev = XEN_BLOCK_DEVICE(xendev); 922 923 if (!object_property_set_str(OBJECT(xendev), "vdev", vdev, 924 errp)) { 925 error_prepend(errp, "failed to set 'vdev': "); 926 goto fail; 927 } 928 929 if (!object_property_set_str(OBJECT(xendev), "drive", 930 xen_block_drive_get_node_name(drive), 931 errp)) { 932 error_prepend(errp, "failed to set 'drive': "); 933 goto fail; 934 } 935 936 if (!object_property_set_str(OBJECT(xendev), "iothread", iothread->id, 937 errp)) { 938 error_prepend(errp, "failed to set 'iothread': "); 939 goto fail; 940 } 941 942 blockdev->iothread = iothread; 943 blockdev->drive = drive; 944 945 if (!qdev_realize_and_unref(DEVICE(xendev), BUS(xenbus), errp)) { 946 error_prepend(errp, "realization of device %s failed: ", type); 947 goto fail; 948 } 949 950 xen_backend_set_device(backend, xendev); 951 return; 952 953 fail: 954 if (xendev) { 955 object_unparent(OBJECT(xendev)); 956 } 957 958 if (iothread) { 959 xen_block_iothread_destroy(iothread, NULL); 960 } 961 962 if (drive) { 963 xen_block_drive_destroy(drive, NULL); 964 } 965 } 966 967 static void xen_block_device_destroy(XenBackendInstance *backend, 968 Error **errp) 969 { 970 ERRP_GUARD(); 971 XenDevice *xendev = xen_backend_get_device(backend); 972 XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev); 973 XenBlockVdev *vdev = &blockdev->props.vdev; 974 XenBlockDrive *drive = blockdev->drive; 975 XenBlockIOThread *iothread = blockdev->iothread; 976 977 trace_xen_block_device_destroy(vdev->number); 978 979 object_unparent(OBJECT(xendev)); 980 981 if (iothread) { 982 xen_block_iothread_destroy(iothread, errp); 983 if (*errp) { 984 error_prepend(errp, "failed to destroy iothread: "); 985 return; 986 } 987 } 988 989 if (drive) { 990 xen_block_drive_destroy(drive, errp); 991 if (*errp) { 992 error_prepend(errp, "failed to destroy drive: "); 993 return; 994 } 995 } 996 } 997 998 static const XenBackendInfo xen_block_backend_info = { 999 .type = "qdisk", 1000 .create = xen_block_device_create, 1001 .destroy = xen_block_device_destroy, 1002 }; 1003 1004 static void xen_block_register_backend(void) 1005 { 1006 xen_backend_register(&xen_block_backend_info); 1007 } 1008 1009 xen_backend_init(xen_block_register_backend); 1010