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 Property *prop = opaque; 339 XenBlockVdev *vdev = qdev_get_prop_ptr(obj, prop); 340 char *str; 341 342 switch (vdev->type) { 343 case XEN_BLOCK_VDEV_TYPE_DP: 344 str = g_strdup_printf("d%lup%lu", vdev->disk, vdev->partition); 345 break; 346 347 case XEN_BLOCK_VDEV_TYPE_XVD: 348 case XEN_BLOCK_VDEV_TYPE_HD: 349 case XEN_BLOCK_VDEV_TYPE_SD: { 350 char *name = disk_to_vbd_name(vdev->disk); 351 352 str = g_strdup_printf("%s%s%lu", 353 (vdev->type == XEN_BLOCK_VDEV_TYPE_XVD) ? 354 "xvd" : 355 (vdev->type == XEN_BLOCK_VDEV_TYPE_HD) ? 356 "hd" : 357 "sd", 358 name, vdev->partition); 359 g_free(name); 360 break; 361 } 362 default: 363 error_setg(errp, "invalid vdev type"); 364 return; 365 } 366 367 visit_type_str(v, name, &str, errp); 368 g_free(str); 369 } 370 371 static int vbd_name_to_disk(const char *name, const char **endp, 372 unsigned long *disk) 373 { 374 unsigned int n = 0; 375 376 while (*name != '\0') { 377 if (!g_ascii_isalpha(*name) || !g_ascii_islower(*name)) { 378 break; 379 } 380 381 n *= 26; 382 n += *name++ - 'a' + 1; 383 } 384 *endp = name; 385 386 if (!n) { 387 return -1; 388 } 389 390 *disk = n - 1; 391 392 return 0; 393 } 394 395 static void xen_block_set_vdev(Object *obj, Visitor *v, const char *name, 396 void *opaque, Error **errp) 397 { 398 DeviceState *dev = DEVICE(obj); 399 Property *prop = opaque; 400 XenBlockVdev *vdev = qdev_get_prop_ptr(obj, prop); 401 char *str, *p; 402 const char *end; 403 404 if (dev->realized) { 405 qdev_prop_set_after_realize(dev, name, errp); 406 return; 407 } 408 409 if (!visit_type_str(v, name, &str, errp)) { 410 return; 411 } 412 413 p = strchr(str, 'd'); 414 if (!p) { 415 goto invalid; 416 } 417 418 *p++ = '\0'; 419 if (*str == '\0') { 420 vdev->type = XEN_BLOCK_VDEV_TYPE_DP; 421 } else if (strcmp(str, "xv") == 0) { 422 vdev->type = XEN_BLOCK_VDEV_TYPE_XVD; 423 } else if (strcmp(str, "h") == 0) { 424 vdev->type = XEN_BLOCK_VDEV_TYPE_HD; 425 } else if (strcmp(str, "s") == 0) { 426 vdev->type = XEN_BLOCK_VDEV_TYPE_SD; 427 } else { 428 goto invalid; 429 } 430 431 if (vdev->type == XEN_BLOCK_VDEV_TYPE_DP) { 432 if (qemu_strtoul(p, &end, 10, &vdev->disk)) { 433 goto invalid; 434 } 435 436 if (*end == 'p') { 437 if (*(++end) == '\0') { 438 goto invalid; 439 } 440 } 441 } else { 442 if (vbd_name_to_disk(p, &end, &vdev->disk)) { 443 goto invalid; 444 } 445 } 446 447 if (*end != '\0') { 448 p = (char *)end; 449 450 if (qemu_strtoul(p, &end, 10, &vdev->partition)) { 451 goto invalid; 452 } 453 454 if (*end != '\0') { 455 goto invalid; 456 } 457 } else { 458 vdev->partition = 0; 459 } 460 461 switch (vdev->type) { 462 case XEN_BLOCK_VDEV_TYPE_DP: 463 case XEN_BLOCK_VDEV_TYPE_XVD: 464 if (vdev->disk < (1 << 4) && vdev->partition < (1 << 4)) { 465 vdev->number = (202 << 8) | (vdev->disk << 4) | 466 vdev->partition; 467 } else if (vdev->disk < (1 << 20) && vdev->partition < (1 << 8)) { 468 vdev->number = (1 << 28) | (vdev->disk << 8) | 469 vdev->partition; 470 } else { 471 goto invalid; 472 } 473 break; 474 475 case XEN_BLOCK_VDEV_TYPE_HD: 476 if ((vdev->disk == 0 || vdev->disk == 1) && 477 vdev->partition < (1 << 6)) { 478 vdev->number = (3 << 8) | (vdev->disk << 6) | vdev->partition; 479 } else if ((vdev->disk == 2 || vdev->disk == 3) && 480 vdev->partition < (1 << 6)) { 481 vdev->number = (22 << 8) | ((vdev->disk - 2) << 6) | 482 vdev->partition; 483 } else { 484 goto invalid; 485 } 486 break; 487 488 case XEN_BLOCK_VDEV_TYPE_SD: 489 if (vdev->disk < (1 << 4) && vdev->partition < (1 << 4)) { 490 vdev->number = (8 << 8) | (vdev->disk << 4) | vdev->partition; 491 } else { 492 goto invalid; 493 } 494 break; 495 496 default: 497 goto invalid; 498 } 499 500 g_free(str); 501 return; 502 503 invalid: 504 error_setg(errp, "invalid virtual disk specifier"); 505 506 vdev->type = XEN_BLOCK_VDEV_TYPE_INVALID; 507 g_free(str); 508 } 509 510 /* 511 * This property deals with 'vdev' names adhering to the Xen VBD naming 512 * scheme described in: 513 * 514 * https://xenbits.xen.org/docs/unstable/man/xen-vbd-interface.7.html 515 */ 516 const PropertyInfo xen_block_prop_vdev = { 517 .name = "str", 518 .description = "Virtual Disk specifier: d*p*/xvd*/hd*/sd*", 519 .get = xen_block_get_vdev, 520 .set = xen_block_set_vdev, 521 }; 522 523 static Property xen_block_props[] = { 524 DEFINE_PROP("vdev", XenBlockDevice, props.vdev, 525 xen_block_prop_vdev, XenBlockVdev), 526 DEFINE_BLOCK_PROPERTIES(XenBlockDevice, props.conf), 527 DEFINE_PROP_UINT32("max-ring-page-order", XenBlockDevice, 528 props.max_ring_page_order, 4), 529 DEFINE_PROP_LINK("iothread", XenBlockDevice, props.iothread, 530 TYPE_IOTHREAD, IOThread *), 531 DEFINE_PROP_END_OF_LIST() 532 }; 533 534 static void xen_block_class_init(ObjectClass *class, void *data) 535 { 536 DeviceClass *dev_class = DEVICE_CLASS(class); 537 XenDeviceClass *xendev_class = XEN_DEVICE_CLASS(class); 538 539 xendev_class->backend = "qdisk"; 540 xendev_class->device = "vbd"; 541 xendev_class->get_name = xen_block_get_name; 542 xendev_class->realize = xen_block_realize; 543 xendev_class->frontend_changed = xen_block_frontend_changed; 544 xendev_class->unrealize = xen_block_unrealize; 545 546 device_class_set_props(dev_class, xen_block_props); 547 } 548 549 static const TypeInfo xen_block_type_info = { 550 .name = TYPE_XEN_BLOCK_DEVICE, 551 .parent = TYPE_XEN_DEVICE, 552 .instance_size = sizeof(XenBlockDevice), 553 .abstract = true, 554 .class_size = sizeof(XenBlockDeviceClass), 555 .class_init = xen_block_class_init, 556 }; 557 558 static void xen_disk_unrealize(XenBlockDevice *blockdev) 559 { 560 trace_xen_disk_unrealize(); 561 } 562 563 static void xen_disk_realize(XenBlockDevice *blockdev, Error **errp) 564 { 565 BlockConf *conf = &blockdev->props.conf; 566 567 trace_xen_disk_realize(); 568 569 blockdev->device_type = "disk"; 570 571 if (!conf->blk) { 572 error_setg(errp, "drive property not set"); 573 return; 574 } 575 576 blockdev->info = blk_is_read_only(conf->blk) ? VDISK_READONLY : 0; 577 } 578 579 static void xen_disk_class_init(ObjectClass *class, void *data) 580 { 581 DeviceClass *dev_class = DEVICE_CLASS(class); 582 XenBlockDeviceClass *blockdev_class = XEN_BLOCK_DEVICE_CLASS(class); 583 584 blockdev_class->realize = xen_disk_realize; 585 blockdev_class->unrealize = xen_disk_unrealize; 586 587 dev_class->desc = "Xen Disk Device"; 588 } 589 590 static const TypeInfo xen_disk_type_info = { 591 .name = TYPE_XEN_DISK_DEVICE, 592 .parent = TYPE_XEN_BLOCK_DEVICE, 593 .instance_size = sizeof(XenDiskDevice), 594 .class_init = xen_disk_class_init, 595 }; 596 597 static void xen_cdrom_unrealize(XenBlockDevice *blockdev) 598 { 599 trace_xen_cdrom_unrealize(); 600 } 601 602 static void xen_cdrom_realize(XenBlockDevice *blockdev, Error **errp) 603 { 604 BlockConf *conf = &blockdev->props.conf; 605 606 trace_xen_cdrom_realize(); 607 608 blockdev->device_type = "cdrom"; 609 610 if (!conf->blk) { 611 int rc; 612 613 /* Set up an empty drive */ 614 conf->blk = blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL); 615 616 rc = blk_attach_dev(conf->blk, DEVICE(blockdev)); 617 if (!rc) { 618 error_setg_errno(errp, -rc, "failed to create drive"); 619 return; 620 } 621 } 622 623 blockdev->info = VDISK_READONLY | VDISK_CDROM; 624 } 625 626 static void xen_cdrom_class_init(ObjectClass *class, void *data) 627 { 628 DeviceClass *dev_class = DEVICE_CLASS(class); 629 XenBlockDeviceClass *blockdev_class = XEN_BLOCK_DEVICE_CLASS(class); 630 631 blockdev_class->realize = xen_cdrom_realize; 632 blockdev_class->unrealize = xen_cdrom_unrealize; 633 634 dev_class->desc = "Xen CD-ROM Device"; 635 } 636 637 static const TypeInfo xen_cdrom_type_info = { 638 .name = TYPE_XEN_CDROM_DEVICE, 639 .parent = TYPE_XEN_BLOCK_DEVICE, 640 .instance_size = sizeof(XenCDRomDevice), 641 .class_init = xen_cdrom_class_init, 642 }; 643 644 static void xen_block_register_types(void) 645 { 646 type_register_static(&xen_block_type_info); 647 type_register_static(&xen_disk_type_info); 648 type_register_static(&xen_cdrom_type_info); 649 } 650 651 type_init(xen_block_register_types) 652 653 static void xen_block_blockdev_del(const char *node_name, Error **errp) 654 { 655 trace_xen_block_blockdev_del(node_name); 656 657 qmp_blockdev_del(node_name, errp); 658 } 659 660 static char *xen_block_blockdev_add(const char *id, QDict *qdict, 661 Error **errp) 662 { 663 ERRP_GUARD(); 664 const char *driver = qdict_get_try_str(qdict, "driver"); 665 BlockdevOptions *options = NULL; 666 char *node_name; 667 Visitor *v; 668 669 if (!driver) { 670 error_setg(errp, "no 'driver' parameter"); 671 return NULL; 672 } 673 674 node_name = g_strdup_printf("%s-%s", id, driver); 675 qdict_put_str(qdict, "node-name", node_name); 676 677 trace_xen_block_blockdev_add(node_name); 678 679 v = qobject_input_visitor_new(QOBJECT(qdict)); 680 visit_type_BlockdevOptions(v, NULL, &options, errp); 681 visit_free(v); 682 if (!options) { 683 goto fail; 684 } 685 686 qmp_blockdev_add(options, errp); 687 688 if (*errp) { 689 goto fail; 690 } 691 692 qapi_free_BlockdevOptions(options); 693 694 return node_name; 695 696 fail: 697 if (options) { 698 qapi_free_BlockdevOptions(options); 699 } 700 g_free(node_name); 701 702 return NULL; 703 } 704 705 static void xen_block_drive_destroy(XenBlockDrive *drive, Error **errp) 706 { 707 ERRP_GUARD(); 708 char *node_name = drive->node_name; 709 710 if (node_name) { 711 xen_block_blockdev_del(node_name, errp); 712 if (*errp) { 713 return; 714 } 715 g_free(node_name); 716 drive->node_name = NULL; 717 } 718 g_free(drive->id); 719 g_free(drive); 720 } 721 722 static XenBlockDrive *xen_block_drive_create(const char *id, 723 const char *device_type, 724 QDict *opts, Error **errp) 725 { 726 ERRP_GUARD(); 727 const char *params = qdict_get_try_str(opts, "params"); 728 const char *mode = qdict_get_try_str(opts, "mode"); 729 const char *direct_io_safe = qdict_get_try_str(opts, "direct-io-safe"); 730 const char *discard_enable = qdict_get_try_str(opts, "discard-enable"); 731 char *driver = NULL; 732 char *filename = NULL; 733 XenBlockDrive *drive = NULL; 734 QDict *file_layer; 735 QDict *driver_layer; 736 737 if (params) { 738 char **v = g_strsplit(params, ":", 2); 739 740 if (v[1] == NULL) { 741 filename = g_strdup(v[0]); 742 driver = g_strdup("raw"); 743 } else { 744 if (strcmp(v[0], "aio") == 0) { 745 driver = g_strdup("raw"); 746 } else if (strcmp(v[0], "vhd") == 0) { 747 driver = g_strdup("vpc"); 748 } else { 749 driver = g_strdup(v[0]); 750 } 751 filename = g_strdup(v[1]); 752 } 753 754 g_strfreev(v); 755 } else { 756 error_setg(errp, "no params"); 757 goto done; 758 } 759 760 assert(filename); 761 assert(driver); 762 763 drive = g_new0(XenBlockDrive, 1); 764 drive->id = g_strdup(id); 765 766 file_layer = qdict_new(); 767 driver_layer = qdict_new(); 768 769 qdict_put_str(file_layer, "driver", "file"); 770 qdict_put_str(file_layer, "filename", filename); 771 g_free(filename); 772 773 if (mode && *mode != 'w') { 774 qdict_put_bool(file_layer, "read-only", true); 775 } 776 777 if (direct_io_safe) { 778 unsigned long value; 779 780 if (!qemu_strtoul(direct_io_safe, NULL, 2, &value) && !!value) { 781 QDict *cache_qdict = qdict_new(); 782 783 qdict_put_bool(cache_qdict, "direct", true); 784 qdict_put(file_layer, "cache", cache_qdict); 785 786 qdict_put_str(file_layer, "aio", "native"); 787 } 788 } 789 790 if (discard_enable) { 791 unsigned long value; 792 793 if (!qemu_strtoul(discard_enable, NULL, 2, &value) && !!value) { 794 qdict_put_str(file_layer, "discard", "unmap"); 795 qdict_put_str(driver_layer, "discard", "unmap"); 796 } 797 } 798 799 /* 800 * It is necessary to turn file locking off as an emulated device 801 * may have already opened the same image file. 802 */ 803 qdict_put_str(file_layer, "locking", "off"); 804 805 qdict_put_str(driver_layer, "driver", driver); 806 g_free(driver); 807 808 qdict_put(driver_layer, "file", file_layer); 809 810 g_assert(!drive->node_name); 811 drive->node_name = xen_block_blockdev_add(drive->id, driver_layer, 812 errp); 813 814 qobject_unref(driver_layer); 815 816 done: 817 if (*errp) { 818 xen_block_drive_destroy(drive, NULL); 819 return NULL; 820 } 821 822 return drive; 823 } 824 825 static const char *xen_block_drive_get_node_name(XenBlockDrive *drive) 826 { 827 return drive->node_name ? drive->node_name : ""; 828 } 829 830 static void xen_block_iothread_destroy(XenBlockIOThread *iothread, 831 Error **errp) 832 { 833 qmp_object_del(iothread->id, errp); 834 835 g_free(iothread->id); 836 g_free(iothread); 837 } 838 839 static XenBlockIOThread *xen_block_iothread_create(const char *id, 840 Error **errp) 841 { 842 ERRP_GUARD(); 843 XenBlockIOThread *iothread = g_new(XenBlockIOThread, 1); 844 QDict *opts; 845 QObject *ret_data = NULL; 846 847 iothread->id = g_strdup(id); 848 849 opts = qdict_new(); 850 qdict_put_str(opts, "qom-type", TYPE_IOTHREAD); 851 qdict_put_str(opts, "id", id); 852 qmp_object_add(opts, &ret_data, errp); 853 qobject_unref(opts); 854 qobject_unref(ret_data); 855 856 if (*errp) { 857 g_free(iothread->id); 858 g_free(iothread); 859 return NULL; 860 } 861 862 return iothread; 863 } 864 865 static void xen_block_device_create(XenBackendInstance *backend, 866 QDict *opts, Error **errp) 867 { 868 ERRP_GUARD(); 869 XenBus *xenbus = xen_backend_get_bus(backend); 870 const char *name = xen_backend_get_name(backend); 871 unsigned long number; 872 const char *vdev, *device_type; 873 XenBlockDrive *drive = NULL; 874 XenBlockIOThread *iothread = NULL; 875 XenDevice *xendev = NULL; 876 const char *type; 877 XenBlockDevice *blockdev; 878 879 if (qemu_strtoul(name, NULL, 10, &number)) { 880 error_setg(errp, "failed to parse name '%s'", name); 881 goto fail; 882 } 883 884 trace_xen_block_device_create(number); 885 886 vdev = qdict_get_try_str(opts, "dev"); 887 if (!vdev) { 888 error_setg(errp, "no dev parameter"); 889 goto fail; 890 } 891 892 device_type = qdict_get_try_str(opts, "device-type"); 893 if (!device_type) { 894 error_setg(errp, "no device-type parameter"); 895 goto fail; 896 } 897 898 if (!strcmp(device_type, "disk")) { 899 type = TYPE_XEN_DISK_DEVICE; 900 } else if (!strcmp(device_type, "cdrom")) { 901 type = TYPE_XEN_CDROM_DEVICE; 902 } else { 903 error_setg(errp, "invalid device-type parameter '%s'", device_type); 904 goto fail; 905 } 906 907 drive = xen_block_drive_create(vdev, device_type, opts, errp); 908 if (!drive) { 909 error_prepend(errp, "failed to create drive: "); 910 goto fail; 911 } 912 913 iothread = xen_block_iothread_create(vdev, errp); 914 if (*errp) { 915 error_prepend(errp, "failed to create iothread: "); 916 goto fail; 917 } 918 919 xendev = XEN_DEVICE(qdev_new(type)); 920 blockdev = XEN_BLOCK_DEVICE(xendev); 921 922 if (!object_property_set_str(OBJECT(xendev), "vdev", vdev, 923 errp)) { 924 error_prepend(errp, "failed to set 'vdev': "); 925 goto fail; 926 } 927 928 if (!object_property_set_str(OBJECT(xendev), "drive", 929 xen_block_drive_get_node_name(drive), 930 errp)) { 931 error_prepend(errp, "failed to set 'drive': "); 932 goto fail; 933 } 934 935 if (!object_property_set_str(OBJECT(xendev), "iothread", iothread->id, 936 errp)) { 937 error_prepend(errp, "failed to set 'iothread': "); 938 goto fail; 939 } 940 941 blockdev->iothread = iothread; 942 blockdev->drive = drive; 943 944 if (!qdev_realize_and_unref(DEVICE(xendev), BUS(xenbus), errp)) { 945 error_prepend(errp, "realization of device %s failed: ", type); 946 goto fail; 947 } 948 949 xen_backend_set_device(backend, xendev); 950 return; 951 952 fail: 953 if (xendev) { 954 object_unparent(OBJECT(xendev)); 955 } 956 957 if (iothread) { 958 xen_block_iothread_destroy(iothread, NULL); 959 } 960 961 if (drive) { 962 xen_block_drive_destroy(drive, NULL); 963 } 964 } 965 966 static void xen_block_device_destroy(XenBackendInstance *backend, 967 Error **errp) 968 { 969 ERRP_GUARD(); 970 XenDevice *xendev = xen_backend_get_device(backend); 971 XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev); 972 XenBlockVdev *vdev = &blockdev->props.vdev; 973 XenBlockDrive *drive = blockdev->drive; 974 XenBlockIOThread *iothread = blockdev->iothread; 975 976 trace_xen_block_device_destroy(vdev->number); 977 978 object_unparent(OBJECT(xendev)); 979 980 if (iothread) { 981 xen_block_iothread_destroy(iothread, errp); 982 if (*errp) { 983 error_prepend(errp, "failed to destroy iothread: "); 984 return; 985 } 986 } 987 988 if (drive) { 989 xen_block_drive_destroy(drive, errp); 990 if (*errp) { 991 error_prepend(errp, "failed to destroy drive: "); 992 return; 993 } 994 } 995 } 996 997 static const XenBackendInfo xen_block_backend_info = { 998 .type = "qdisk", 999 .create = xen_block_device_create, 1000 .destroy = xen_block_device_destroy, 1001 }; 1002 1003 static void xen_block_register_backend(void) 1004 { 1005 xen_backend_register(&xen_block_backend_info); 1006 } 1007 1008 xen_backend_init(xen_block_register_backend); 1009