1 /* 2 * Virtio Block Device 3 * 4 * Copyright IBM, Corp. 2007 5 * 6 * Authors: 7 * Anthony Liguori <aliguori@us.ibm.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2. See 10 * the COPYING file in the top-level directory. 11 * 12 */ 13 14 #include "qemu/osdep.h" 15 #include "qapi/error.h" 16 #include "qemu/iov.h" 17 #include "qemu/module.h" 18 #include "qemu/error-report.h" 19 #include "trace.h" 20 #include "hw/block/block.h" 21 #include "hw/qdev-properties.h" 22 #include "sysemu/blockdev.h" 23 #include "sysemu/sysemu.h" 24 #include "sysemu/runstate.h" 25 #include "hw/virtio/virtio-blk.h" 26 #include "dataplane/virtio-blk.h" 27 #include "scsi/constants.h" 28 #ifdef __linux__ 29 # include <scsi/sg.h> 30 #endif 31 #include "hw/virtio/virtio-bus.h" 32 #include "migration/qemu-file-types.h" 33 #include "hw/virtio/virtio-access.h" 34 35 /* Config size before the discard support (hide associated config fields) */ 36 #define VIRTIO_BLK_CFG_SIZE offsetof(struct virtio_blk_config, \ 37 max_discard_sectors) 38 /* 39 * Starting from the discard feature, we can use this array to properly 40 * set the config size depending on the features enabled. 41 */ 42 static VirtIOFeature feature_sizes[] = { 43 {.flags = 1ULL << VIRTIO_BLK_F_DISCARD, 44 .end = virtio_endof(struct virtio_blk_config, discard_sector_alignment)}, 45 {.flags = 1ULL << VIRTIO_BLK_F_WRITE_ZEROES, 46 .end = virtio_endof(struct virtio_blk_config, write_zeroes_may_unmap)}, 47 {} 48 }; 49 50 static void virtio_blk_set_config_size(VirtIOBlock *s, uint64_t host_features) 51 { 52 s->config_size = MAX(VIRTIO_BLK_CFG_SIZE, 53 virtio_feature_get_config_size(feature_sizes, host_features)); 54 55 assert(s->config_size <= sizeof(struct virtio_blk_config)); 56 } 57 58 static void virtio_blk_init_request(VirtIOBlock *s, VirtQueue *vq, 59 VirtIOBlockReq *req) 60 { 61 req->dev = s; 62 req->vq = vq; 63 req->qiov.size = 0; 64 req->in_len = 0; 65 req->next = NULL; 66 req->mr_next = NULL; 67 } 68 69 static void virtio_blk_free_request(VirtIOBlockReq *req) 70 { 71 g_free(req); 72 } 73 74 static void virtio_blk_req_complete(VirtIOBlockReq *req, unsigned char status) 75 { 76 VirtIOBlock *s = req->dev; 77 VirtIODevice *vdev = VIRTIO_DEVICE(s); 78 79 trace_virtio_blk_req_complete(vdev, req, status); 80 81 stb_p(&req->in->status, status); 82 virtqueue_push(req->vq, &req->elem, req->in_len); 83 if (s->dataplane_started && !s->dataplane_disabled) { 84 virtio_blk_data_plane_notify(s->dataplane, req->vq); 85 } else { 86 virtio_notify(vdev, req->vq); 87 } 88 } 89 90 static int virtio_blk_handle_rw_error(VirtIOBlockReq *req, int error, 91 bool is_read, bool acct_failed) 92 { 93 VirtIOBlock *s = req->dev; 94 BlockErrorAction action = blk_get_error_action(s->blk, is_read, error); 95 96 if (action == BLOCK_ERROR_ACTION_STOP) { 97 /* Break the link as the next request is going to be parsed from the 98 * ring again. Otherwise we may end up doing a double completion! */ 99 req->mr_next = NULL; 100 req->next = s->rq; 101 s->rq = req; 102 } else if (action == BLOCK_ERROR_ACTION_REPORT) { 103 virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR); 104 if (acct_failed) { 105 block_acct_failed(blk_get_stats(s->blk), &req->acct); 106 } 107 virtio_blk_free_request(req); 108 } 109 110 blk_error_action(s->blk, action, is_read, error); 111 return action != BLOCK_ERROR_ACTION_IGNORE; 112 } 113 114 static void virtio_blk_rw_complete(void *opaque, int ret) 115 { 116 VirtIOBlockReq *next = opaque; 117 VirtIOBlock *s = next->dev; 118 VirtIODevice *vdev = VIRTIO_DEVICE(s); 119 120 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 121 while (next) { 122 VirtIOBlockReq *req = next; 123 next = req->mr_next; 124 trace_virtio_blk_rw_complete(vdev, req, ret); 125 126 if (req->qiov.nalloc != -1) { 127 /* If nalloc is != -1 req->qiov is a local copy of the original 128 * external iovec. It was allocated in submit_requests to be 129 * able to merge requests. */ 130 qemu_iovec_destroy(&req->qiov); 131 } 132 133 if (ret) { 134 int p = virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type); 135 bool is_read = !(p & VIRTIO_BLK_T_OUT); 136 /* Note that memory may be dirtied on read failure. If the 137 * virtio request is not completed here, as is the case for 138 * BLOCK_ERROR_ACTION_STOP, the memory may not be copied 139 * correctly during live migration. While this is ugly, 140 * it is acceptable because the device is free to write to 141 * the memory until the request is completed (which will 142 * happen on the other side of the migration). 143 */ 144 if (virtio_blk_handle_rw_error(req, -ret, is_read, true)) { 145 continue; 146 } 147 } 148 149 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); 150 block_acct_done(blk_get_stats(s->blk), &req->acct); 151 virtio_blk_free_request(req); 152 } 153 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 154 } 155 156 static void virtio_blk_flush_complete(void *opaque, int ret) 157 { 158 VirtIOBlockReq *req = opaque; 159 VirtIOBlock *s = req->dev; 160 161 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 162 if (ret) { 163 if (virtio_blk_handle_rw_error(req, -ret, 0, true)) { 164 goto out; 165 } 166 } 167 168 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); 169 block_acct_done(blk_get_stats(s->blk), &req->acct); 170 virtio_blk_free_request(req); 171 172 out: 173 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 174 } 175 176 static void virtio_blk_discard_write_zeroes_complete(void *opaque, int ret) 177 { 178 VirtIOBlockReq *req = opaque; 179 VirtIOBlock *s = req->dev; 180 bool is_write_zeroes = (virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type) & 181 ~VIRTIO_BLK_T_BARRIER) == VIRTIO_BLK_T_WRITE_ZEROES; 182 183 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 184 if (ret) { 185 if (virtio_blk_handle_rw_error(req, -ret, false, is_write_zeroes)) { 186 goto out; 187 } 188 } 189 190 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); 191 if (is_write_zeroes) { 192 block_acct_done(blk_get_stats(s->blk), &req->acct); 193 } 194 virtio_blk_free_request(req); 195 196 out: 197 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 198 } 199 200 #ifdef __linux__ 201 202 typedef struct { 203 VirtIOBlockReq *req; 204 struct sg_io_hdr hdr; 205 } VirtIOBlockIoctlReq; 206 207 static void virtio_blk_ioctl_complete(void *opaque, int status) 208 { 209 VirtIOBlockIoctlReq *ioctl_req = opaque; 210 VirtIOBlockReq *req = ioctl_req->req; 211 VirtIOBlock *s = req->dev; 212 VirtIODevice *vdev = VIRTIO_DEVICE(s); 213 struct virtio_scsi_inhdr *scsi; 214 struct sg_io_hdr *hdr; 215 216 scsi = (void *)req->elem.in_sg[req->elem.in_num - 2].iov_base; 217 218 if (status) { 219 status = VIRTIO_BLK_S_UNSUPP; 220 virtio_stl_p(vdev, &scsi->errors, 255); 221 goto out; 222 } 223 224 hdr = &ioctl_req->hdr; 225 /* 226 * From SCSI-Generic-HOWTO: "Some lower level drivers (e.g. ide-scsi) 227 * clear the masked_status field [hence status gets cleared too, see 228 * block/scsi_ioctl.c] even when a CHECK_CONDITION or COMMAND_TERMINATED 229 * status has occurred. However they do set DRIVER_SENSE in driver_status 230 * field. Also a (sb_len_wr > 0) indicates there is a sense buffer. 231 */ 232 if (hdr->status == 0 && hdr->sb_len_wr > 0) { 233 hdr->status = CHECK_CONDITION; 234 } 235 236 virtio_stl_p(vdev, &scsi->errors, 237 hdr->status | (hdr->msg_status << 8) | 238 (hdr->host_status << 16) | (hdr->driver_status << 24)); 239 virtio_stl_p(vdev, &scsi->residual, hdr->resid); 240 virtio_stl_p(vdev, &scsi->sense_len, hdr->sb_len_wr); 241 virtio_stl_p(vdev, &scsi->data_len, hdr->dxfer_len); 242 243 out: 244 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 245 virtio_blk_req_complete(req, status); 246 virtio_blk_free_request(req); 247 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 248 g_free(ioctl_req); 249 } 250 251 #endif 252 253 static VirtIOBlockReq *virtio_blk_get_request(VirtIOBlock *s, VirtQueue *vq) 254 { 255 VirtIOBlockReq *req = virtqueue_pop(vq, sizeof(VirtIOBlockReq)); 256 257 if (req) { 258 virtio_blk_init_request(s, vq, req); 259 } 260 return req; 261 } 262 263 static int virtio_blk_handle_scsi_req(VirtIOBlockReq *req) 264 { 265 int status = VIRTIO_BLK_S_OK; 266 struct virtio_scsi_inhdr *scsi = NULL; 267 VirtIOBlock *blk = req->dev; 268 VirtIODevice *vdev = VIRTIO_DEVICE(blk); 269 VirtQueueElement *elem = &req->elem; 270 271 #ifdef __linux__ 272 int i; 273 VirtIOBlockIoctlReq *ioctl_req; 274 BlockAIOCB *acb; 275 #endif 276 277 /* 278 * We require at least one output segment each for the virtio_blk_outhdr 279 * and the SCSI command block. 280 * 281 * We also at least require the virtio_blk_inhdr, the virtio_scsi_inhdr 282 * and the sense buffer pointer in the input segments. 283 */ 284 if (elem->out_num < 2 || elem->in_num < 3) { 285 status = VIRTIO_BLK_S_IOERR; 286 goto fail; 287 } 288 289 /* 290 * The scsi inhdr is placed in the second-to-last input segment, just 291 * before the regular inhdr. 292 */ 293 scsi = (void *)elem->in_sg[elem->in_num - 2].iov_base; 294 295 if (!virtio_has_feature(blk->host_features, VIRTIO_BLK_F_SCSI)) { 296 status = VIRTIO_BLK_S_UNSUPP; 297 goto fail; 298 } 299 300 /* 301 * No support for bidirection commands yet. 302 */ 303 if (elem->out_num > 2 && elem->in_num > 3) { 304 status = VIRTIO_BLK_S_UNSUPP; 305 goto fail; 306 } 307 308 #ifdef __linux__ 309 ioctl_req = g_new0(VirtIOBlockIoctlReq, 1); 310 ioctl_req->req = req; 311 ioctl_req->hdr.interface_id = 'S'; 312 ioctl_req->hdr.cmd_len = elem->out_sg[1].iov_len; 313 ioctl_req->hdr.cmdp = elem->out_sg[1].iov_base; 314 ioctl_req->hdr.dxfer_len = 0; 315 316 if (elem->out_num > 2) { 317 /* 318 * If there are more than the minimally required 2 output segments 319 * there is write payload starting from the third iovec. 320 */ 321 ioctl_req->hdr.dxfer_direction = SG_DXFER_TO_DEV; 322 ioctl_req->hdr.iovec_count = elem->out_num - 2; 323 324 for (i = 0; i < ioctl_req->hdr.iovec_count; i++) { 325 ioctl_req->hdr.dxfer_len += elem->out_sg[i + 2].iov_len; 326 } 327 328 ioctl_req->hdr.dxferp = elem->out_sg + 2; 329 330 } else if (elem->in_num > 3) { 331 /* 332 * If we have more than 3 input segments the guest wants to actually 333 * read data. 334 */ 335 ioctl_req->hdr.dxfer_direction = SG_DXFER_FROM_DEV; 336 ioctl_req->hdr.iovec_count = elem->in_num - 3; 337 for (i = 0; i < ioctl_req->hdr.iovec_count; i++) { 338 ioctl_req->hdr.dxfer_len += elem->in_sg[i].iov_len; 339 } 340 341 ioctl_req->hdr.dxferp = elem->in_sg; 342 } else { 343 /* 344 * Some SCSI commands don't actually transfer any data. 345 */ 346 ioctl_req->hdr.dxfer_direction = SG_DXFER_NONE; 347 } 348 349 ioctl_req->hdr.sbp = elem->in_sg[elem->in_num - 3].iov_base; 350 ioctl_req->hdr.mx_sb_len = elem->in_sg[elem->in_num - 3].iov_len; 351 352 acb = blk_aio_ioctl(blk->blk, SG_IO, &ioctl_req->hdr, 353 virtio_blk_ioctl_complete, ioctl_req); 354 if (!acb) { 355 g_free(ioctl_req); 356 status = VIRTIO_BLK_S_UNSUPP; 357 goto fail; 358 } 359 return -EINPROGRESS; 360 #else 361 abort(); 362 #endif 363 364 fail: 365 /* Just put anything nonzero so that the ioctl fails in the guest. */ 366 if (scsi) { 367 virtio_stl_p(vdev, &scsi->errors, 255); 368 } 369 return status; 370 } 371 372 static void virtio_blk_handle_scsi(VirtIOBlockReq *req) 373 { 374 int status; 375 376 status = virtio_blk_handle_scsi_req(req); 377 if (status != -EINPROGRESS) { 378 virtio_blk_req_complete(req, status); 379 virtio_blk_free_request(req); 380 } 381 } 382 383 static inline void submit_requests(BlockBackend *blk, MultiReqBuffer *mrb, 384 int start, int num_reqs, int niov) 385 { 386 QEMUIOVector *qiov = &mrb->reqs[start]->qiov; 387 int64_t sector_num = mrb->reqs[start]->sector_num; 388 bool is_write = mrb->is_write; 389 390 if (num_reqs > 1) { 391 int i; 392 struct iovec *tmp_iov = qiov->iov; 393 int tmp_niov = qiov->niov; 394 395 /* mrb->reqs[start]->qiov was initialized from external so we can't 396 * modify it here. We need to initialize it locally and then add the 397 * external iovecs. */ 398 qemu_iovec_init(qiov, niov); 399 400 for (i = 0; i < tmp_niov; i++) { 401 qemu_iovec_add(qiov, tmp_iov[i].iov_base, tmp_iov[i].iov_len); 402 } 403 404 for (i = start + 1; i < start + num_reqs; i++) { 405 qemu_iovec_concat(qiov, &mrb->reqs[i]->qiov, 0, 406 mrb->reqs[i]->qiov.size); 407 mrb->reqs[i - 1]->mr_next = mrb->reqs[i]; 408 } 409 410 trace_virtio_blk_submit_multireq(VIRTIO_DEVICE(mrb->reqs[start]->dev), 411 mrb, start, num_reqs, 412 sector_num << BDRV_SECTOR_BITS, 413 qiov->size, is_write); 414 block_acct_merge_done(blk_get_stats(blk), 415 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ, 416 num_reqs - 1); 417 } 418 419 if (is_write) { 420 blk_aio_pwritev(blk, sector_num << BDRV_SECTOR_BITS, qiov, 0, 421 virtio_blk_rw_complete, mrb->reqs[start]); 422 } else { 423 blk_aio_preadv(blk, sector_num << BDRV_SECTOR_BITS, qiov, 0, 424 virtio_blk_rw_complete, mrb->reqs[start]); 425 } 426 } 427 428 static int multireq_compare(const void *a, const void *b) 429 { 430 const VirtIOBlockReq *req1 = *(VirtIOBlockReq **)a, 431 *req2 = *(VirtIOBlockReq **)b; 432 433 /* 434 * Note that we can't simply subtract sector_num1 from sector_num2 435 * here as that could overflow the return value. 436 */ 437 if (req1->sector_num > req2->sector_num) { 438 return 1; 439 } else if (req1->sector_num < req2->sector_num) { 440 return -1; 441 } else { 442 return 0; 443 } 444 } 445 446 static void virtio_blk_submit_multireq(BlockBackend *blk, MultiReqBuffer *mrb) 447 { 448 int i = 0, start = 0, num_reqs = 0, niov = 0, nb_sectors = 0; 449 uint32_t max_transfer; 450 int64_t sector_num = 0; 451 452 if (mrb->num_reqs == 1) { 453 submit_requests(blk, mrb, 0, 1, -1); 454 mrb->num_reqs = 0; 455 return; 456 } 457 458 max_transfer = blk_get_max_transfer(mrb->reqs[0]->dev->blk); 459 460 qsort(mrb->reqs, mrb->num_reqs, sizeof(*mrb->reqs), 461 &multireq_compare); 462 463 for (i = 0; i < mrb->num_reqs; i++) { 464 VirtIOBlockReq *req = mrb->reqs[i]; 465 if (num_reqs > 0) { 466 /* 467 * NOTE: We cannot merge the requests in below situations: 468 * 1. requests are not sequential 469 * 2. merge would exceed maximum number of IOVs 470 * 3. merge would exceed maximum transfer length of backend device 471 */ 472 if (sector_num + nb_sectors != req->sector_num || 473 niov > blk_get_max_iov(blk) - req->qiov.niov || 474 req->qiov.size > max_transfer || 475 nb_sectors > (max_transfer - 476 req->qiov.size) / BDRV_SECTOR_SIZE) { 477 submit_requests(blk, mrb, start, num_reqs, niov); 478 num_reqs = 0; 479 } 480 } 481 482 if (num_reqs == 0) { 483 sector_num = req->sector_num; 484 nb_sectors = niov = 0; 485 start = i; 486 } 487 488 nb_sectors += req->qiov.size / BDRV_SECTOR_SIZE; 489 niov += req->qiov.niov; 490 num_reqs++; 491 } 492 493 submit_requests(blk, mrb, start, num_reqs, niov); 494 mrb->num_reqs = 0; 495 } 496 497 static void virtio_blk_handle_flush(VirtIOBlockReq *req, MultiReqBuffer *mrb) 498 { 499 VirtIOBlock *s = req->dev; 500 501 block_acct_start(blk_get_stats(s->blk), &req->acct, 0, 502 BLOCK_ACCT_FLUSH); 503 504 /* 505 * Make sure all outstanding writes are posted to the backing device. 506 */ 507 if (mrb->is_write && mrb->num_reqs > 0) { 508 virtio_blk_submit_multireq(s->blk, mrb); 509 } 510 blk_aio_flush(s->blk, virtio_blk_flush_complete, req); 511 } 512 513 static bool virtio_blk_sect_range_ok(VirtIOBlock *dev, 514 uint64_t sector, size_t size) 515 { 516 uint64_t nb_sectors = size >> BDRV_SECTOR_BITS; 517 uint64_t total_sectors; 518 519 if (nb_sectors > BDRV_REQUEST_MAX_SECTORS) { 520 return false; 521 } 522 if (sector & dev->sector_mask) { 523 return false; 524 } 525 if (size % dev->conf.conf.logical_block_size) { 526 return false; 527 } 528 blk_get_geometry(dev->blk, &total_sectors); 529 if (sector > total_sectors || nb_sectors > total_sectors - sector) { 530 return false; 531 } 532 return true; 533 } 534 535 static uint8_t virtio_blk_handle_discard_write_zeroes(VirtIOBlockReq *req, 536 struct virtio_blk_discard_write_zeroes *dwz_hdr, bool is_write_zeroes) 537 { 538 VirtIOBlock *s = req->dev; 539 VirtIODevice *vdev = VIRTIO_DEVICE(s); 540 uint64_t sector; 541 uint32_t num_sectors, flags, max_sectors; 542 uint8_t err_status; 543 int bytes; 544 545 sector = virtio_ldq_p(vdev, &dwz_hdr->sector); 546 num_sectors = virtio_ldl_p(vdev, &dwz_hdr->num_sectors); 547 flags = virtio_ldl_p(vdev, &dwz_hdr->flags); 548 max_sectors = is_write_zeroes ? s->conf.max_write_zeroes_sectors : 549 s->conf.max_discard_sectors; 550 551 /* 552 * max_sectors is at most BDRV_REQUEST_MAX_SECTORS, this check 553 * make us sure that "num_sectors << BDRV_SECTOR_BITS" can fit in 554 * the integer variable. 555 */ 556 if (unlikely(num_sectors > max_sectors)) { 557 err_status = VIRTIO_BLK_S_IOERR; 558 goto err; 559 } 560 561 bytes = num_sectors << BDRV_SECTOR_BITS; 562 563 if (unlikely(!virtio_blk_sect_range_ok(s, sector, bytes))) { 564 err_status = VIRTIO_BLK_S_IOERR; 565 goto err; 566 } 567 568 /* 569 * The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for discard 570 * and write zeroes commands if any unknown flag is set. 571 */ 572 if (unlikely(flags & ~VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) { 573 err_status = VIRTIO_BLK_S_UNSUPP; 574 goto err; 575 } 576 577 if (is_write_zeroes) { /* VIRTIO_BLK_T_WRITE_ZEROES */ 578 int blk_aio_flags = 0; 579 580 if (flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP) { 581 blk_aio_flags |= BDRV_REQ_MAY_UNMAP; 582 } 583 584 block_acct_start(blk_get_stats(s->blk), &req->acct, bytes, 585 BLOCK_ACCT_WRITE); 586 587 blk_aio_pwrite_zeroes(s->blk, sector << BDRV_SECTOR_BITS, 588 bytes, blk_aio_flags, 589 virtio_blk_discard_write_zeroes_complete, req); 590 } else { /* VIRTIO_BLK_T_DISCARD */ 591 /* 592 * The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for 593 * discard commands if the unmap flag is set. 594 */ 595 if (unlikely(flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) { 596 err_status = VIRTIO_BLK_S_UNSUPP; 597 goto err; 598 } 599 600 blk_aio_pdiscard(s->blk, sector << BDRV_SECTOR_BITS, bytes, 601 virtio_blk_discard_write_zeroes_complete, req); 602 } 603 604 return VIRTIO_BLK_S_OK; 605 606 err: 607 if (is_write_zeroes) { 608 block_acct_invalid(blk_get_stats(s->blk), BLOCK_ACCT_WRITE); 609 } 610 return err_status; 611 } 612 613 static int virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb) 614 { 615 uint32_t type; 616 struct iovec *in_iov = req->elem.in_sg; 617 struct iovec *out_iov = req->elem.out_sg; 618 unsigned in_num = req->elem.in_num; 619 unsigned out_num = req->elem.out_num; 620 VirtIOBlock *s = req->dev; 621 VirtIODevice *vdev = VIRTIO_DEVICE(s); 622 623 if (req->elem.out_num < 1 || req->elem.in_num < 1) { 624 virtio_error(vdev, "virtio-blk missing headers"); 625 return -1; 626 } 627 628 if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out, 629 sizeof(req->out)) != sizeof(req->out))) { 630 virtio_error(vdev, "virtio-blk request outhdr too short"); 631 return -1; 632 } 633 634 iov_discard_front(&out_iov, &out_num, sizeof(req->out)); 635 636 if (in_iov[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) { 637 virtio_error(vdev, "virtio-blk request inhdr too short"); 638 return -1; 639 } 640 641 /* We always touch the last byte, so just see how big in_iov is. */ 642 req->in_len = iov_size(in_iov, in_num); 643 req->in = (void *)in_iov[in_num - 1].iov_base 644 + in_iov[in_num - 1].iov_len 645 - sizeof(struct virtio_blk_inhdr); 646 iov_discard_back(in_iov, &in_num, sizeof(struct virtio_blk_inhdr)); 647 648 type = virtio_ldl_p(vdev, &req->out.type); 649 650 /* VIRTIO_BLK_T_OUT defines the command direction. VIRTIO_BLK_T_BARRIER 651 * is an optional flag. Although a guest should not send this flag if 652 * not negotiated we ignored it in the past. So keep ignoring it. */ 653 switch (type & ~(VIRTIO_BLK_T_OUT | VIRTIO_BLK_T_BARRIER)) { 654 case VIRTIO_BLK_T_IN: 655 { 656 bool is_write = type & VIRTIO_BLK_T_OUT; 657 req->sector_num = virtio_ldq_p(vdev, &req->out.sector); 658 659 if (is_write) { 660 qemu_iovec_init_external(&req->qiov, out_iov, out_num); 661 trace_virtio_blk_handle_write(vdev, req, req->sector_num, 662 req->qiov.size / BDRV_SECTOR_SIZE); 663 } else { 664 qemu_iovec_init_external(&req->qiov, in_iov, in_num); 665 trace_virtio_blk_handle_read(vdev, req, req->sector_num, 666 req->qiov.size / BDRV_SECTOR_SIZE); 667 } 668 669 if (!virtio_blk_sect_range_ok(s, req->sector_num, req->qiov.size)) { 670 virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR); 671 block_acct_invalid(blk_get_stats(s->blk), 672 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ); 673 virtio_blk_free_request(req); 674 return 0; 675 } 676 677 block_acct_start(blk_get_stats(s->blk), &req->acct, req->qiov.size, 678 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ); 679 680 /* merge would exceed maximum number of requests or IO direction 681 * changes */ 682 if (mrb->num_reqs > 0 && (mrb->num_reqs == VIRTIO_BLK_MAX_MERGE_REQS || 683 is_write != mrb->is_write || 684 !s->conf.request_merging)) { 685 virtio_blk_submit_multireq(s->blk, mrb); 686 } 687 688 assert(mrb->num_reqs < VIRTIO_BLK_MAX_MERGE_REQS); 689 mrb->reqs[mrb->num_reqs++] = req; 690 mrb->is_write = is_write; 691 break; 692 } 693 case VIRTIO_BLK_T_FLUSH: 694 virtio_blk_handle_flush(req, mrb); 695 break; 696 case VIRTIO_BLK_T_SCSI_CMD: 697 virtio_blk_handle_scsi(req); 698 break; 699 case VIRTIO_BLK_T_GET_ID: 700 { 701 /* 702 * NB: per existing s/n string convention the string is 703 * terminated by '\0' only when shorter than buffer. 704 */ 705 const char *serial = s->conf.serial ? s->conf.serial : ""; 706 size_t size = MIN(strlen(serial) + 1, 707 MIN(iov_size(in_iov, in_num), 708 VIRTIO_BLK_ID_BYTES)); 709 iov_from_buf(in_iov, in_num, 0, serial, size); 710 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); 711 virtio_blk_free_request(req); 712 break; 713 } 714 /* 715 * VIRTIO_BLK_T_DISCARD and VIRTIO_BLK_T_WRITE_ZEROES are defined with 716 * VIRTIO_BLK_T_OUT flag set. We masked this flag in the switch statement, 717 * so we must mask it for these requests, then we will check if it is set. 718 */ 719 case VIRTIO_BLK_T_DISCARD & ~VIRTIO_BLK_T_OUT: 720 case VIRTIO_BLK_T_WRITE_ZEROES & ~VIRTIO_BLK_T_OUT: 721 { 722 struct virtio_blk_discard_write_zeroes dwz_hdr; 723 size_t out_len = iov_size(out_iov, out_num); 724 bool is_write_zeroes = (type & ~VIRTIO_BLK_T_BARRIER) == 725 VIRTIO_BLK_T_WRITE_ZEROES; 726 uint8_t err_status; 727 728 /* 729 * Unsupported if VIRTIO_BLK_T_OUT is not set or the request contains 730 * more than one segment. 731 */ 732 if (unlikely(!(type & VIRTIO_BLK_T_OUT) || 733 out_len > sizeof(dwz_hdr))) { 734 virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP); 735 virtio_blk_free_request(req); 736 return 0; 737 } 738 739 if (unlikely(iov_to_buf(out_iov, out_num, 0, &dwz_hdr, 740 sizeof(dwz_hdr)) != sizeof(dwz_hdr))) { 741 virtio_error(vdev, "virtio-blk discard/write_zeroes header" 742 " too short"); 743 return -1; 744 } 745 746 err_status = virtio_blk_handle_discard_write_zeroes(req, &dwz_hdr, 747 is_write_zeroes); 748 if (err_status != VIRTIO_BLK_S_OK) { 749 virtio_blk_req_complete(req, err_status); 750 virtio_blk_free_request(req); 751 } 752 753 break; 754 } 755 default: 756 virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP); 757 virtio_blk_free_request(req); 758 } 759 return 0; 760 } 761 762 bool virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq) 763 { 764 VirtIOBlockReq *req; 765 MultiReqBuffer mrb = {}; 766 bool progress = false; 767 768 aio_context_acquire(blk_get_aio_context(s->blk)); 769 blk_io_plug(s->blk); 770 771 do { 772 virtio_queue_set_notification(vq, 0); 773 774 while ((req = virtio_blk_get_request(s, vq))) { 775 progress = true; 776 if (virtio_blk_handle_request(req, &mrb)) { 777 virtqueue_detach_element(req->vq, &req->elem, 0); 778 virtio_blk_free_request(req); 779 break; 780 } 781 } 782 783 virtio_queue_set_notification(vq, 1); 784 } while (!virtio_queue_empty(vq)); 785 786 if (mrb.num_reqs) { 787 virtio_blk_submit_multireq(s->blk, &mrb); 788 } 789 790 blk_io_unplug(s->blk); 791 aio_context_release(blk_get_aio_context(s->blk)); 792 return progress; 793 } 794 795 static void virtio_blk_handle_output_do(VirtIOBlock *s, VirtQueue *vq) 796 { 797 virtio_blk_handle_vq(s, vq); 798 } 799 800 static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq) 801 { 802 VirtIOBlock *s = (VirtIOBlock *)vdev; 803 804 if (s->dataplane) { 805 /* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start 806 * dataplane here instead of waiting for .set_status(). 807 */ 808 virtio_device_start_ioeventfd(vdev); 809 if (!s->dataplane_disabled) { 810 return; 811 } 812 } 813 virtio_blk_handle_output_do(s, vq); 814 } 815 816 static void virtio_blk_dma_restart_bh(void *opaque) 817 { 818 VirtIOBlock *s = opaque; 819 VirtIOBlockReq *req = s->rq; 820 MultiReqBuffer mrb = {}; 821 822 qemu_bh_delete(s->bh); 823 s->bh = NULL; 824 825 s->rq = NULL; 826 827 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 828 while (req) { 829 VirtIOBlockReq *next = req->next; 830 if (virtio_blk_handle_request(req, &mrb)) { 831 /* Device is now broken and won't do any processing until it gets 832 * reset. Already queued requests will be lost: let's purge them. 833 */ 834 while (req) { 835 next = req->next; 836 virtqueue_detach_element(req->vq, &req->elem, 0); 837 virtio_blk_free_request(req); 838 req = next; 839 } 840 break; 841 } 842 req = next; 843 } 844 845 if (mrb.num_reqs) { 846 virtio_blk_submit_multireq(s->blk, &mrb); 847 } 848 blk_dec_in_flight(s->conf.conf.blk); 849 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 850 } 851 852 static void virtio_blk_dma_restart_cb(void *opaque, int running, 853 RunState state) 854 { 855 VirtIOBlock *s = opaque; 856 857 if (!running) { 858 return; 859 } 860 861 if (!s->bh) { 862 /* FIXME The data plane is not started yet, so these requests are 863 * processed in the main thread. */ 864 s->bh = aio_bh_new(blk_get_aio_context(s->conf.conf.blk), 865 virtio_blk_dma_restart_bh, s); 866 blk_inc_in_flight(s->conf.conf.blk); 867 qemu_bh_schedule(s->bh); 868 } 869 } 870 871 static void virtio_blk_reset(VirtIODevice *vdev) 872 { 873 VirtIOBlock *s = VIRTIO_BLK(vdev); 874 AioContext *ctx; 875 VirtIOBlockReq *req; 876 877 ctx = blk_get_aio_context(s->blk); 878 aio_context_acquire(ctx); 879 blk_drain(s->blk); 880 881 /* We drop queued requests after blk_drain() because blk_drain() itself can 882 * produce them. */ 883 while (s->rq) { 884 req = s->rq; 885 s->rq = req->next; 886 virtqueue_detach_element(req->vq, &req->elem, 0); 887 virtio_blk_free_request(req); 888 } 889 890 aio_context_release(ctx); 891 892 assert(!s->dataplane_started); 893 blk_set_enable_write_cache(s->blk, s->original_wce); 894 } 895 896 /* coalesce internal state, copy to pci i/o region 0 897 */ 898 static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config) 899 { 900 VirtIOBlock *s = VIRTIO_BLK(vdev); 901 BlockConf *conf = &s->conf.conf; 902 struct virtio_blk_config blkcfg; 903 uint64_t capacity; 904 int64_t length; 905 int blk_size = conf->logical_block_size; 906 907 blk_get_geometry(s->blk, &capacity); 908 memset(&blkcfg, 0, sizeof(blkcfg)); 909 virtio_stq_p(vdev, &blkcfg.capacity, capacity); 910 virtio_stl_p(vdev, &blkcfg.seg_max, 128 - 2); 911 virtio_stw_p(vdev, &blkcfg.geometry.cylinders, conf->cyls); 912 virtio_stl_p(vdev, &blkcfg.blk_size, blk_size); 913 virtio_stw_p(vdev, &blkcfg.min_io_size, conf->min_io_size / blk_size); 914 virtio_stw_p(vdev, &blkcfg.opt_io_size, conf->opt_io_size / blk_size); 915 blkcfg.geometry.heads = conf->heads; 916 /* 917 * We must ensure that the block device capacity is a multiple of 918 * the logical block size. If that is not the case, let's use 919 * sector_mask to adopt the geometry to have a correct picture. 920 * For those devices where the capacity is ok for the given geometry 921 * we don't touch the sector value of the geometry, since some devices 922 * (like s390 dasd) need a specific value. Here the capacity is already 923 * cyls*heads*secs*blk_size and the sector value is not block size 924 * divided by 512 - instead it is the amount of blk_size blocks 925 * per track (cylinder). 926 */ 927 length = blk_getlength(s->blk); 928 if (length > 0 && length / conf->heads / conf->secs % blk_size) { 929 blkcfg.geometry.sectors = conf->secs & ~s->sector_mask; 930 } else { 931 blkcfg.geometry.sectors = conf->secs; 932 } 933 blkcfg.size_max = 0; 934 blkcfg.physical_block_exp = get_physical_block_exp(conf); 935 blkcfg.alignment_offset = 0; 936 blkcfg.wce = blk_enable_write_cache(s->blk); 937 virtio_stw_p(vdev, &blkcfg.num_queues, s->conf.num_queues); 938 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD)) { 939 virtio_stl_p(vdev, &blkcfg.max_discard_sectors, 940 s->conf.max_discard_sectors); 941 virtio_stl_p(vdev, &blkcfg.discard_sector_alignment, 942 blk_size >> BDRV_SECTOR_BITS); 943 /* 944 * We support only one segment per request since multiple segments 945 * are not widely used and there are no userspace APIs that allow 946 * applications to submit multiple segments in a single call. 947 */ 948 virtio_stl_p(vdev, &blkcfg.max_discard_seg, 1); 949 } 950 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES)) { 951 virtio_stl_p(vdev, &blkcfg.max_write_zeroes_sectors, 952 s->conf.max_write_zeroes_sectors); 953 blkcfg.write_zeroes_may_unmap = 1; 954 virtio_stl_p(vdev, &blkcfg.max_write_zeroes_seg, 1); 955 } 956 memcpy(config, &blkcfg, s->config_size); 957 } 958 959 static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config) 960 { 961 VirtIOBlock *s = VIRTIO_BLK(vdev); 962 struct virtio_blk_config blkcfg; 963 964 memcpy(&blkcfg, config, s->config_size); 965 966 aio_context_acquire(blk_get_aio_context(s->blk)); 967 blk_set_enable_write_cache(s->blk, blkcfg.wce != 0); 968 aio_context_release(blk_get_aio_context(s->blk)); 969 } 970 971 static uint64_t virtio_blk_get_features(VirtIODevice *vdev, uint64_t features, 972 Error **errp) 973 { 974 VirtIOBlock *s = VIRTIO_BLK(vdev); 975 976 /* Firstly sync all virtio-blk possible supported features */ 977 features |= s->host_features; 978 979 virtio_add_feature(&features, VIRTIO_BLK_F_SEG_MAX); 980 virtio_add_feature(&features, VIRTIO_BLK_F_GEOMETRY); 981 virtio_add_feature(&features, VIRTIO_BLK_F_TOPOLOGY); 982 virtio_add_feature(&features, VIRTIO_BLK_F_BLK_SIZE); 983 if (virtio_has_feature(features, VIRTIO_F_VERSION_1)) { 984 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_SCSI)) { 985 error_setg(errp, "Please set scsi=off for virtio-blk devices in order to use virtio 1.0"); 986 return 0; 987 } 988 } else { 989 virtio_clear_feature(&features, VIRTIO_F_ANY_LAYOUT); 990 virtio_add_feature(&features, VIRTIO_BLK_F_SCSI); 991 } 992 993 if (blk_enable_write_cache(s->blk)) { 994 virtio_add_feature(&features, VIRTIO_BLK_F_WCE); 995 } 996 if (blk_is_read_only(s->blk)) { 997 virtio_add_feature(&features, VIRTIO_BLK_F_RO); 998 } 999 if (s->conf.num_queues > 1) { 1000 virtio_add_feature(&features, VIRTIO_BLK_F_MQ); 1001 } 1002 1003 return features; 1004 } 1005 1006 static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status) 1007 { 1008 VirtIOBlock *s = VIRTIO_BLK(vdev); 1009 1010 if (!(status & (VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK))) { 1011 assert(!s->dataplane_started); 1012 } 1013 1014 if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) { 1015 return; 1016 } 1017 1018 /* A guest that supports VIRTIO_BLK_F_CONFIG_WCE must be able to send 1019 * cache flushes. Thus, the "auto writethrough" behavior is never 1020 * necessary for guests that support the VIRTIO_BLK_F_CONFIG_WCE feature. 1021 * Leaving it enabled would break the following sequence: 1022 * 1023 * Guest started with "-drive cache=writethrough" 1024 * Guest sets status to 0 1025 * Guest sets DRIVER bit in status field 1026 * Guest reads host features (WCE=0, CONFIG_WCE=1) 1027 * Guest writes guest features (WCE=0, CONFIG_WCE=1) 1028 * Guest writes 1 to the WCE configuration field (writeback mode) 1029 * Guest sets DRIVER_OK bit in status field 1030 * 1031 * s->blk would erroneously be placed in writethrough mode. 1032 */ 1033 if (!virtio_vdev_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE)) { 1034 aio_context_acquire(blk_get_aio_context(s->blk)); 1035 blk_set_enable_write_cache(s->blk, 1036 virtio_vdev_has_feature(vdev, 1037 VIRTIO_BLK_F_WCE)); 1038 aio_context_release(blk_get_aio_context(s->blk)); 1039 } 1040 } 1041 1042 static void virtio_blk_save_device(VirtIODevice *vdev, QEMUFile *f) 1043 { 1044 VirtIOBlock *s = VIRTIO_BLK(vdev); 1045 VirtIOBlockReq *req = s->rq; 1046 1047 while (req) { 1048 qemu_put_sbyte(f, 1); 1049 1050 if (s->conf.num_queues > 1) { 1051 qemu_put_be32(f, virtio_get_queue_index(req->vq)); 1052 } 1053 1054 qemu_put_virtqueue_element(f, &req->elem); 1055 req = req->next; 1056 } 1057 qemu_put_sbyte(f, 0); 1058 } 1059 1060 static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f, 1061 int version_id) 1062 { 1063 VirtIOBlock *s = VIRTIO_BLK(vdev); 1064 1065 while (qemu_get_sbyte(f)) { 1066 unsigned nvqs = s->conf.num_queues; 1067 unsigned vq_idx = 0; 1068 VirtIOBlockReq *req; 1069 1070 if (nvqs > 1) { 1071 vq_idx = qemu_get_be32(f); 1072 1073 if (vq_idx >= nvqs) { 1074 error_report("Invalid virtqueue index in request list: %#x", 1075 vq_idx); 1076 return -EINVAL; 1077 } 1078 } 1079 1080 req = qemu_get_virtqueue_element(vdev, f, sizeof(VirtIOBlockReq)); 1081 virtio_blk_init_request(s, virtio_get_queue(vdev, vq_idx), req); 1082 req->next = s->rq; 1083 s->rq = req; 1084 } 1085 1086 return 0; 1087 } 1088 1089 static void virtio_blk_resize(void *opaque) 1090 { 1091 VirtIODevice *vdev = VIRTIO_DEVICE(opaque); 1092 1093 virtio_notify_config(vdev); 1094 } 1095 1096 static const BlockDevOps virtio_block_ops = { 1097 .resize_cb = virtio_blk_resize, 1098 }; 1099 1100 static void virtio_blk_device_realize(DeviceState *dev, Error **errp) 1101 { 1102 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 1103 VirtIOBlock *s = VIRTIO_BLK(dev); 1104 VirtIOBlkConf *conf = &s->conf; 1105 Error *err = NULL; 1106 unsigned i; 1107 1108 if (!conf->conf.blk) { 1109 error_setg(errp, "drive property not set"); 1110 return; 1111 } 1112 if (!blk_is_inserted(conf->conf.blk)) { 1113 error_setg(errp, "Device needs media, but drive is empty"); 1114 return; 1115 } 1116 if (!conf->num_queues) { 1117 error_setg(errp, "num-queues property must be larger than 0"); 1118 return; 1119 } 1120 if (!is_power_of_2(conf->queue_size) || 1121 conf->queue_size > VIRTQUEUE_MAX_SIZE) { 1122 error_setg(errp, "invalid queue-size property (%" PRIu16 "), " 1123 "must be a power of 2 (max %d)", 1124 conf->queue_size, VIRTQUEUE_MAX_SIZE); 1125 return; 1126 } 1127 1128 if (!blkconf_apply_backend_options(&conf->conf, 1129 blk_is_read_only(conf->conf.blk), true, 1130 errp)) { 1131 return; 1132 } 1133 s->original_wce = blk_enable_write_cache(conf->conf.blk); 1134 if (!blkconf_geometry(&conf->conf, NULL, 65535, 255, 255, errp)) { 1135 return; 1136 } 1137 1138 blkconf_blocksizes(&conf->conf); 1139 1140 if (conf->conf.logical_block_size > 1141 conf->conf.physical_block_size) { 1142 error_setg(errp, 1143 "logical_block_size > physical_block_size not supported"); 1144 return; 1145 } 1146 1147 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD) && 1148 (!conf->max_discard_sectors || 1149 conf->max_discard_sectors > BDRV_REQUEST_MAX_SECTORS)) { 1150 error_setg(errp, "invalid max-discard-sectors property (%" PRIu32 ")" 1151 ", must be between 1 and %d", 1152 conf->max_discard_sectors, (int)BDRV_REQUEST_MAX_SECTORS); 1153 return; 1154 } 1155 1156 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES) && 1157 (!conf->max_write_zeroes_sectors || 1158 conf->max_write_zeroes_sectors > BDRV_REQUEST_MAX_SECTORS)) { 1159 error_setg(errp, "invalid max-write-zeroes-sectors property (%" PRIu32 1160 "), must be between 1 and %d", 1161 conf->max_write_zeroes_sectors, 1162 (int)BDRV_REQUEST_MAX_SECTORS); 1163 return; 1164 } 1165 1166 virtio_blk_set_config_size(s, s->host_features); 1167 1168 virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, s->config_size); 1169 1170 s->blk = conf->conf.blk; 1171 s->rq = NULL; 1172 s->sector_mask = (s->conf.conf.logical_block_size / BDRV_SECTOR_SIZE) - 1; 1173 1174 for (i = 0; i < conf->num_queues; i++) { 1175 virtio_add_queue(vdev, conf->queue_size, virtio_blk_handle_output); 1176 } 1177 virtio_blk_data_plane_create(vdev, conf, &s->dataplane, &err); 1178 if (err != NULL) { 1179 error_propagate(errp, err); 1180 virtio_cleanup(vdev); 1181 return; 1182 } 1183 1184 s->change = qemu_add_vm_change_state_handler(virtio_blk_dma_restart_cb, s); 1185 blk_set_dev_ops(s->blk, &virtio_block_ops, s); 1186 blk_set_guest_block_size(s->blk, s->conf.conf.logical_block_size); 1187 1188 blk_iostatus_enable(s->blk); 1189 } 1190 1191 static void virtio_blk_device_unrealize(DeviceState *dev, Error **errp) 1192 { 1193 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 1194 VirtIOBlock *s = VIRTIO_BLK(dev); 1195 1196 virtio_blk_data_plane_destroy(s->dataplane); 1197 s->dataplane = NULL; 1198 qemu_del_vm_change_state_handler(s->change); 1199 blockdev_mark_auto_del(s->blk); 1200 virtio_cleanup(vdev); 1201 } 1202 1203 static void virtio_blk_instance_init(Object *obj) 1204 { 1205 VirtIOBlock *s = VIRTIO_BLK(obj); 1206 1207 device_add_bootindex_property(obj, &s->conf.conf.bootindex, 1208 "bootindex", "/disk@0,0", 1209 DEVICE(obj), NULL); 1210 } 1211 1212 static const VMStateDescription vmstate_virtio_blk = { 1213 .name = "virtio-blk", 1214 .minimum_version_id = 2, 1215 .version_id = 2, 1216 .fields = (VMStateField[]) { 1217 VMSTATE_VIRTIO_DEVICE, 1218 VMSTATE_END_OF_LIST() 1219 }, 1220 }; 1221 1222 static Property virtio_blk_properties[] = { 1223 DEFINE_BLOCK_PROPERTIES(VirtIOBlock, conf.conf), 1224 DEFINE_BLOCK_ERROR_PROPERTIES(VirtIOBlock, conf.conf), 1225 DEFINE_BLOCK_CHS_PROPERTIES(VirtIOBlock, conf.conf), 1226 DEFINE_PROP_STRING("serial", VirtIOBlock, conf.serial), 1227 DEFINE_PROP_BIT64("config-wce", VirtIOBlock, host_features, 1228 VIRTIO_BLK_F_CONFIG_WCE, true), 1229 #ifdef __linux__ 1230 DEFINE_PROP_BIT64("scsi", VirtIOBlock, host_features, 1231 VIRTIO_BLK_F_SCSI, false), 1232 #endif 1233 DEFINE_PROP_BIT("request-merging", VirtIOBlock, conf.request_merging, 0, 1234 true), 1235 DEFINE_PROP_UINT16("num-queues", VirtIOBlock, conf.num_queues, 1), 1236 DEFINE_PROP_UINT16("queue-size", VirtIOBlock, conf.queue_size, 128), 1237 DEFINE_PROP_LINK("iothread", VirtIOBlock, conf.iothread, TYPE_IOTHREAD, 1238 IOThread *), 1239 DEFINE_PROP_BIT64("discard", VirtIOBlock, host_features, 1240 VIRTIO_BLK_F_DISCARD, true), 1241 DEFINE_PROP_BIT64("write-zeroes", VirtIOBlock, host_features, 1242 VIRTIO_BLK_F_WRITE_ZEROES, true), 1243 DEFINE_PROP_UINT32("max-discard-sectors", VirtIOBlock, 1244 conf.max_discard_sectors, BDRV_REQUEST_MAX_SECTORS), 1245 DEFINE_PROP_UINT32("max-write-zeroes-sectors", VirtIOBlock, 1246 conf.max_write_zeroes_sectors, BDRV_REQUEST_MAX_SECTORS), 1247 DEFINE_PROP_END_OF_LIST(), 1248 }; 1249 1250 static void virtio_blk_class_init(ObjectClass *klass, void *data) 1251 { 1252 DeviceClass *dc = DEVICE_CLASS(klass); 1253 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 1254 1255 dc->props = virtio_blk_properties; 1256 dc->vmsd = &vmstate_virtio_blk; 1257 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 1258 vdc->realize = virtio_blk_device_realize; 1259 vdc->unrealize = virtio_blk_device_unrealize; 1260 vdc->get_config = virtio_blk_update_config; 1261 vdc->set_config = virtio_blk_set_config; 1262 vdc->get_features = virtio_blk_get_features; 1263 vdc->set_status = virtio_blk_set_status; 1264 vdc->reset = virtio_blk_reset; 1265 vdc->save = virtio_blk_save_device; 1266 vdc->load = virtio_blk_load_device; 1267 vdc->start_ioeventfd = virtio_blk_data_plane_start; 1268 vdc->stop_ioeventfd = virtio_blk_data_plane_stop; 1269 } 1270 1271 static const TypeInfo virtio_blk_info = { 1272 .name = TYPE_VIRTIO_BLK, 1273 .parent = TYPE_VIRTIO_DEVICE, 1274 .instance_size = sizeof(VirtIOBlock), 1275 .instance_init = virtio_blk_instance_init, 1276 .class_init = virtio_blk_class_init, 1277 }; 1278 1279 static void virtio_register_types(void) 1280 { 1281 type_register_static(&virtio_blk_info); 1282 } 1283 1284 type_init(virtio_register_types) 1285