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 "qemu/main-loop.h" 20 #include "trace.h" 21 #include "hw/block/block.h" 22 #include "hw/qdev-properties.h" 23 #include "sysemu/blockdev.h" 24 #include "sysemu/sysemu.h" 25 #include "sysemu/runstate.h" 26 #include "hw/virtio/virtio-blk.h" 27 #include "dataplane/virtio-blk.h" 28 #include "scsi/constants.h" 29 #ifdef __linux__ 30 # include <scsi/sg.h> 31 #endif 32 #include "hw/virtio/virtio-bus.h" 33 #include "migration/qemu-file-types.h" 34 #include "hw/virtio/virtio-access.h" 35 36 /* Config size before the discard support (hide associated config fields) */ 37 #define VIRTIO_BLK_CFG_SIZE offsetof(struct virtio_blk_config, \ 38 max_discard_sectors) 39 /* 40 * Starting from the discard feature, we can use this array to properly 41 * set the config size depending on the features enabled. 42 */ 43 static VirtIOFeature feature_sizes[] = { 44 {.flags = 1ULL << VIRTIO_BLK_F_DISCARD, 45 .end = endof(struct virtio_blk_config, discard_sector_alignment)}, 46 {.flags = 1ULL << VIRTIO_BLK_F_WRITE_ZEROES, 47 .end = endof(struct virtio_blk_config, write_zeroes_may_unmap)}, 48 {} 49 }; 50 51 static void virtio_blk_set_config_size(VirtIOBlock *s, uint64_t host_features) 52 { 53 s->config_size = MAX(VIRTIO_BLK_CFG_SIZE, 54 virtio_feature_get_config_size(feature_sizes, host_features)); 55 56 assert(s->config_size <= sizeof(struct virtio_blk_config)); 57 } 58 59 static void virtio_blk_init_request(VirtIOBlock *s, VirtQueue *vq, 60 VirtIOBlockReq *req) 61 { 62 req->dev = s; 63 req->vq = vq; 64 req->qiov.size = 0; 65 req->in_len = 0; 66 req->next = NULL; 67 req->mr_next = NULL; 68 } 69 70 static void virtio_blk_free_request(VirtIOBlockReq *req) 71 { 72 g_free(req); 73 } 74 75 static void virtio_blk_req_complete(VirtIOBlockReq *req, unsigned char status) 76 { 77 VirtIOBlock *s = req->dev; 78 VirtIODevice *vdev = VIRTIO_DEVICE(s); 79 80 trace_virtio_blk_req_complete(vdev, req, status); 81 82 stb_p(&req->in->status, status); 83 iov_discard_undo(&req->inhdr_undo); 84 iov_discard_undo(&req->outhdr_undo); 85 virtqueue_push(req->vq, &req->elem, req->in_len); 86 if (s->dataplane_started && !s->dataplane_disabled) { 87 virtio_blk_data_plane_notify(s->dataplane, req->vq); 88 } else { 89 virtio_notify(vdev, req->vq); 90 } 91 } 92 93 static int virtio_blk_handle_rw_error(VirtIOBlockReq *req, int error, 94 bool is_read, bool acct_failed) 95 { 96 VirtIOBlock *s = req->dev; 97 BlockErrorAction action = blk_get_error_action(s->blk, is_read, error); 98 99 if (action == BLOCK_ERROR_ACTION_STOP) { 100 /* Break the link as the next request is going to be parsed from the 101 * ring again. Otherwise we may end up doing a double completion! */ 102 req->mr_next = NULL; 103 req->next = s->rq; 104 s->rq = req; 105 } else if (action == BLOCK_ERROR_ACTION_REPORT) { 106 virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR); 107 if (acct_failed) { 108 block_acct_failed(blk_get_stats(s->blk), &req->acct); 109 } 110 virtio_blk_free_request(req); 111 } 112 113 blk_error_action(s->blk, action, is_read, error); 114 return action != BLOCK_ERROR_ACTION_IGNORE; 115 } 116 117 static void virtio_blk_rw_complete(void *opaque, int ret) 118 { 119 VirtIOBlockReq *next = opaque; 120 VirtIOBlock *s = next->dev; 121 VirtIODevice *vdev = VIRTIO_DEVICE(s); 122 123 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 124 while (next) { 125 VirtIOBlockReq *req = next; 126 next = req->mr_next; 127 trace_virtio_blk_rw_complete(vdev, req, ret); 128 129 if (req->qiov.nalloc != -1) { 130 /* If nalloc is != -1 req->qiov is a local copy of the original 131 * external iovec. It was allocated in submit_requests to be 132 * able to merge requests. */ 133 qemu_iovec_destroy(&req->qiov); 134 } 135 136 if (ret) { 137 int p = virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type); 138 bool is_read = !(p & VIRTIO_BLK_T_OUT); 139 /* Note that memory may be dirtied on read failure. If the 140 * virtio request is not completed here, as is the case for 141 * BLOCK_ERROR_ACTION_STOP, the memory may not be copied 142 * correctly during live migration. While this is ugly, 143 * it is acceptable because the device is free to write to 144 * the memory until the request is completed (which will 145 * happen on the other side of the migration). 146 */ 147 if (virtio_blk_handle_rw_error(req, -ret, is_read, true)) { 148 continue; 149 } 150 } 151 152 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); 153 block_acct_done(blk_get_stats(s->blk), &req->acct); 154 virtio_blk_free_request(req); 155 } 156 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 157 } 158 159 static void virtio_blk_flush_complete(void *opaque, int ret) 160 { 161 VirtIOBlockReq *req = opaque; 162 VirtIOBlock *s = req->dev; 163 164 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 165 if (ret) { 166 if (virtio_blk_handle_rw_error(req, -ret, 0, true)) { 167 goto out; 168 } 169 } 170 171 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); 172 block_acct_done(blk_get_stats(s->blk), &req->acct); 173 virtio_blk_free_request(req); 174 175 out: 176 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 177 } 178 179 static void virtio_blk_discard_write_zeroes_complete(void *opaque, int ret) 180 { 181 VirtIOBlockReq *req = opaque; 182 VirtIOBlock *s = req->dev; 183 bool is_write_zeroes = (virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type) & 184 ~VIRTIO_BLK_T_BARRIER) == VIRTIO_BLK_T_WRITE_ZEROES; 185 186 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 187 if (ret) { 188 if (virtio_blk_handle_rw_error(req, -ret, false, is_write_zeroes)) { 189 goto out; 190 } 191 } 192 193 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); 194 if (is_write_zeroes) { 195 block_acct_done(blk_get_stats(s->blk), &req->acct); 196 } 197 virtio_blk_free_request(req); 198 199 out: 200 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 201 } 202 203 #ifdef __linux__ 204 205 typedef struct { 206 VirtIOBlockReq *req; 207 struct sg_io_hdr hdr; 208 } VirtIOBlockIoctlReq; 209 210 static void virtio_blk_ioctl_complete(void *opaque, int status) 211 { 212 VirtIOBlockIoctlReq *ioctl_req = opaque; 213 VirtIOBlockReq *req = ioctl_req->req; 214 VirtIOBlock *s = req->dev; 215 VirtIODevice *vdev = VIRTIO_DEVICE(s); 216 struct virtio_scsi_inhdr *scsi; 217 struct sg_io_hdr *hdr; 218 219 scsi = (void *)req->elem.in_sg[req->elem.in_num - 2].iov_base; 220 221 if (status) { 222 status = VIRTIO_BLK_S_UNSUPP; 223 virtio_stl_p(vdev, &scsi->errors, 255); 224 goto out; 225 } 226 227 hdr = &ioctl_req->hdr; 228 /* 229 * From SCSI-Generic-HOWTO: "Some lower level drivers (e.g. ide-scsi) 230 * clear the masked_status field [hence status gets cleared too, see 231 * block/scsi_ioctl.c] even when a CHECK_CONDITION or COMMAND_TERMINATED 232 * status has occurred. However they do set DRIVER_SENSE in driver_status 233 * field. Also a (sb_len_wr > 0) indicates there is a sense buffer. 234 */ 235 if (hdr->status == 0 && hdr->sb_len_wr > 0) { 236 hdr->status = CHECK_CONDITION; 237 } 238 239 virtio_stl_p(vdev, &scsi->errors, 240 hdr->status | (hdr->msg_status << 8) | 241 (hdr->host_status << 16) | (hdr->driver_status << 24)); 242 virtio_stl_p(vdev, &scsi->residual, hdr->resid); 243 virtio_stl_p(vdev, &scsi->sense_len, hdr->sb_len_wr); 244 virtio_stl_p(vdev, &scsi->data_len, hdr->dxfer_len); 245 246 out: 247 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 248 virtio_blk_req_complete(req, status); 249 virtio_blk_free_request(req); 250 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 251 g_free(ioctl_req); 252 } 253 254 #endif 255 256 static VirtIOBlockReq *virtio_blk_get_request(VirtIOBlock *s, VirtQueue *vq) 257 { 258 VirtIOBlockReq *req = virtqueue_pop(vq, sizeof(VirtIOBlockReq)); 259 260 if (req) { 261 virtio_blk_init_request(s, vq, req); 262 } 263 return req; 264 } 265 266 static int virtio_blk_handle_scsi_req(VirtIOBlockReq *req) 267 { 268 int status = VIRTIO_BLK_S_OK; 269 struct virtio_scsi_inhdr *scsi = NULL; 270 VirtIOBlock *blk = req->dev; 271 VirtIODevice *vdev = VIRTIO_DEVICE(blk); 272 VirtQueueElement *elem = &req->elem; 273 274 #ifdef __linux__ 275 int i; 276 VirtIOBlockIoctlReq *ioctl_req; 277 BlockAIOCB *acb; 278 #endif 279 280 /* 281 * We require at least one output segment each for the virtio_blk_outhdr 282 * and the SCSI command block. 283 * 284 * We also at least require the virtio_blk_inhdr, the virtio_scsi_inhdr 285 * and the sense buffer pointer in the input segments. 286 */ 287 if (elem->out_num < 2 || elem->in_num < 3) { 288 status = VIRTIO_BLK_S_IOERR; 289 goto fail; 290 } 291 292 /* 293 * The scsi inhdr is placed in the second-to-last input segment, just 294 * before the regular inhdr. 295 */ 296 scsi = (void *)elem->in_sg[elem->in_num - 2].iov_base; 297 298 if (!virtio_has_feature(blk->host_features, VIRTIO_BLK_F_SCSI)) { 299 status = VIRTIO_BLK_S_UNSUPP; 300 goto fail; 301 } 302 303 /* 304 * No support for bidirection commands yet. 305 */ 306 if (elem->out_num > 2 && elem->in_num > 3) { 307 status = VIRTIO_BLK_S_UNSUPP; 308 goto fail; 309 } 310 311 #ifdef __linux__ 312 ioctl_req = g_new0(VirtIOBlockIoctlReq, 1); 313 ioctl_req->req = req; 314 ioctl_req->hdr.interface_id = 'S'; 315 ioctl_req->hdr.cmd_len = elem->out_sg[1].iov_len; 316 ioctl_req->hdr.cmdp = elem->out_sg[1].iov_base; 317 ioctl_req->hdr.dxfer_len = 0; 318 319 if (elem->out_num > 2) { 320 /* 321 * If there are more than the minimally required 2 output segments 322 * there is write payload starting from the third iovec. 323 */ 324 ioctl_req->hdr.dxfer_direction = SG_DXFER_TO_DEV; 325 ioctl_req->hdr.iovec_count = elem->out_num - 2; 326 327 for (i = 0; i < ioctl_req->hdr.iovec_count; i++) { 328 ioctl_req->hdr.dxfer_len += elem->out_sg[i + 2].iov_len; 329 } 330 331 ioctl_req->hdr.dxferp = elem->out_sg + 2; 332 333 } else if (elem->in_num > 3) { 334 /* 335 * If we have more than 3 input segments the guest wants to actually 336 * read data. 337 */ 338 ioctl_req->hdr.dxfer_direction = SG_DXFER_FROM_DEV; 339 ioctl_req->hdr.iovec_count = elem->in_num - 3; 340 for (i = 0; i < ioctl_req->hdr.iovec_count; i++) { 341 ioctl_req->hdr.dxfer_len += elem->in_sg[i].iov_len; 342 } 343 344 ioctl_req->hdr.dxferp = elem->in_sg; 345 } else { 346 /* 347 * Some SCSI commands don't actually transfer any data. 348 */ 349 ioctl_req->hdr.dxfer_direction = SG_DXFER_NONE; 350 } 351 352 ioctl_req->hdr.sbp = elem->in_sg[elem->in_num - 3].iov_base; 353 ioctl_req->hdr.mx_sb_len = elem->in_sg[elem->in_num - 3].iov_len; 354 355 acb = blk_aio_ioctl(blk->blk, SG_IO, &ioctl_req->hdr, 356 virtio_blk_ioctl_complete, ioctl_req); 357 if (!acb) { 358 g_free(ioctl_req); 359 status = VIRTIO_BLK_S_UNSUPP; 360 goto fail; 361 } 362 return -EINPROGRESS; 363 #else 364 abort(); 365 #endif 366 367 fail: 368 /* Just put anything nonzero so that the ioctl fails in the guest. */ 369 if (scsi) { 370 virtio_stl_p(vdev, &scsi->errors, 255); 371 } 372 return status; 373 } 374 375 static void virtio_blk_handle_scsi(VirtIOBlockReq *req) 376 { 377 int status; 378 379 status = virtio_blk_handle_scsi_req(req); 380 if (status != -EINPROGRESS) { 381 virtio_blk_req_complete(req, status); 382 virtio_blk_free_request(req); 383 } 384 } 385 386 static inline void submit_requests(BlockBackend *blk, MultiReqBuffer *mrb, 387 int start, int num_reqs, int niov) 388 { 389 QEMUIOVector *qiov = &mrb->reqs[start]->qiov; 390 int64_t sector_num = mrb->reqs[start]->sector_num; 391 bool is_write = mrb->is_write; 392 393 if (num_reqs > 1) { 394 int i; 395 struct iovec *tmp_iov = qiov->iov; 396 int tmp_niov = qiov->niov; 397 398 /* mrb->reqs[start]->qiov was initialized from external so we can't 399 * modify it here. We need to initialize it locally and then add the 400 * external iovecs. */ 401 qemu_iovec_init(qiov, niov); 402 403 for (i = 0; i < tmp_niov; i++) { 404 qemu_iovec_add(qiov, tmp_iov[i].iov_base, tmp_iov[i].iov_len); 405 } 406 407 for (i = start + 1; i < start + num_reqs; i++) { 408 qemu_iovec_concat(qiov, &mrb->reqs[i]->qiov, 0, 409 mrb->reqs[i]->qiov.size); 410 mrb->reqs[i - 1]->mr_next = mrb->reqs[i]; 411 } 412 413 trace_virtio_blk_submit_multireq(VIRTIO_DEVICE(mrb->reqs[start]->dev), 414 mrb, start, num_reqs, 415 sector_num << BDRV_SECTOR_BITS, 416 qiov->size, is_write); 417 block_acct_merge_done(blk_get_stats(blk), 418 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ, 419 num_reqs - 1); 420 } 421 422 if (is_write) { 423 blk_aio_pwritev(blk, sector_num << BDRV_SECTOR_BITS, qiov, 0, 424 virtio_blk_rw_complete, mrb->reqs[start]); 425 } else { 426 blk_aio_preadv(blk, sector_num << BDRV_SECTOR_BITS, qiov, 0, 427 virtio_blk_rw_complete, mrb->reqs[start]); 428 } 429 } 430 431 static int multireq_compare(const void *a, const void *b) 432 { 433 const VirtIOBlockReq *req1 = *(VirtIOBlockReq **)a, 434 *req2 = *(VirtIOBlockReq **)b; 435 436 /* 437 * Note that we can't simply subtract sector_num1 from sector_num2 438 * here as that could overflow the return value. 439 */ 440 if (req1->sector_num > req2->sector_num) { 441 return 1; 442 } else if (req1->sector_num < req2->sector_num) { 443 return -1; 444 } else { 445 return 0; 446 } 447 } 448 449 static void virtio_blk_submit_multireq(BlockBackend *blk, MultiReqBuffer *mrb) 450 { 451 int i = 0, start = 0, num_reqs = 0, niov = 0, nb_sectors = 0; 452 uint32_t max_transfer; 453 int64_t sector_num = 0; 454 455 if (mrb->num_reqs == 1) { 456 submit_requests(blk, mrb, 0, 1, -1); 457 mrb->num_reqs = 0; 458 return; 459 } 460 461 max_transfer = blk_get_max_transfer(mrb->reqs[0]->dev->blk); 462 463 qsort(mrb->reqs, mrb->num_reqs, sizeof(*mrb->reqs), 464 &multireq_compare); 465 466 for (i = 0; i < mrb->num_reqs; i++) { 467 VirtIOBlockReq *req = mrb->reqs[i]; 468 if (num_reqs > 0) { 469 /* 470 * NOTE: We cannot merge the requests in below situations: 471 * 1. requests are not sequential 472 * 2. merge would exceed maximum number of IOVs 473 * 3. merge would exceed maximum transfer length of backend device 474 */ 475 if (sector_num + nb_sectors != req->sector_num || 476 niov > blk_get_max_iov(blk) - req->qiov.niov || 477 req->qiov.size > max_transfer || 478 nb_sectors > (max_transfer - 479 req->qiov.size) / BDRV_SECTOR_SIZE) { 480 submit_requests(blk, mrb, start, num_reqs, niov); 481 num_reqs = 0; 482 } 483 } 484 485 if (num_reqs == 0) { 486 sector_num = req->sector_num; 487 nb_sectors = niov = 0; 488 start = i; 489 } 490 491 nb_sectors += req->qiov.size / BDRV_SECTOR_SIZE; 492 niov += req->qiov.niov; 493 num_reqs++; 494 } 495 496 submit_requests(blk, mrb, start, num_reqs, niov); 497 mrb->num_reqs = 0; 498 } 499 500 static void virtio_blk_handle_flush(VirtIOBlockReq *req, MultiReqBuffer *mrb) 501 { 502 VirtIOBlock *s = req->dev; 503 504 block_acct_start(blk_get_stats(s->blk), &req->acct, 0, 505 BLOCK_ACCT_FLUSH); 506 507 /* 508 * Make sure all outstanding writes are posted to the backing device. 509 */ 510 if (mrb->is_write && mrb->num_reqs > 0) { 511 virtio_blk_submit_multireq(s->blk, mrb); 512 } 513 blk_aio_flush(s->blk, virtio_blk_flush_complete, req); 514 } 515 516 static bool virtio_blk_sect_range_ok(VirtIOBlock *dev, 517 uint64_t sector, size_t size) 518 { 519 uint64_t nb_sectors = size >> BDRV_SECTOR_BITS; 520 uint64_t total_sectors; 521 522 if (nb_sectors > BDRV_REQUEST_MAX_SECTORS) { 523 return false; 524 } 525 if (sector & dev->sector_mask) { 526 return false; 527 } 528 if (size % dev->conf.conf.logical_block_size) { 529 return false; 530 } 531 blk_get_geometry(dev->blk, &total_sectors); 532 if (sector > total_sectors || nb_sectors > total_sectors - sector) { 533 return false; 534 } 535 return true; 536 } 537 538 static uint8_t virtio_blk_handle_discard_write_zeroes(VirtIOBlockReq *req, 539 struct virtio_blk_discard_write_zeroes *dwz_hdr, bool is_write_zeroes) 540 { 541 VirtIOBlock *s = req->dev; 542 VirtIODevice *vdev = VIRTIO_DEVICE(s); 543 uint64_t sector; 544 uint32_t num_sectors, flags, max_sectors; 545 uint8_t err_status; 546 int bytes; 547 548 sector = virtio_ldq_p(vdev, &dwz_hdr->sector); 549 num_sectors = virtio_ldl_p(vdev, &dwz_hdr->num_sectors); 550 flags = virtio_ldl_p(vdev, &dwz_hdr->flags); 551 max_sectors = is_write_zeroes ? s->conf.max_write_zeroes_sectors : 552 s->conf.max_discard_sectors; 553 554 /* 555 * max_sectors is at most BDRV_REQUEST_MAX_SECTORS, this check 556 * make us sure that "num_sectors << BDRV_SECTOR_BITS" can fit in 557 * the integer variable. 558 */ 559 if (unlikely(num_sectors > max_sectors)) { 560 err_status = VIRTIO_BLK_S_IOERR; 561 goto err; 562 } 563 564 bytes = num_sectors << BDRV_SECTOR_BITS; 565 566 if (unlikely(!virtio_blk_sect_range_ok(s, sector, bytes))) { 567 err_status = VIRTIO_BLK_S_IOERR; 568 goto err; 569 } 570 571 /* 572 * The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for discard 573 * and write zeroes commands if any unknown flag is set. 574 */ 575 if (unlikely(flags & ~VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) { 576 err_status = VIRTIO_BLK_S_UNSUPP; 577 goto err; 578 } 579 580 if (is_write_zeroes) { /* VIRTIO_BLK_T_WRITE_ZEROES */ 581 int blk_aio_flags = 0; 582 583 if (flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP) { 584 blk_aio_flags |= BDRV_REQ_MAY_UNMAP; 585 } 586 587 block_acct_start(blk_get_stats(s->blk), &req->acct, bytes, 588 BLOCK_ACCT_WRITE); 589 590 blk_aio_pwrite_zeroes(s->blk, sector << BDRV_SECTOR_BITS, 591 bytes, blk_aio_flags, 592 virtio_blk_discard_write_zeroes_complete, req); 593 } else { /* VIRTIO_BLK_T_DISCARD */ 594 /* 595 * The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for 596 * discard commands if the unmap flag is set. 597 */ 598 if (unlikely(flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) { 599 err_status = VIRTIO_BLK_S_UNSUPP; 600 goto err; 601 } 602 603 blk_aio_pdiscard(s->blk, sector << BDRV_SECTOR_BITS, bytes, 604 virtio_blk_discard_write_zeroes_complete, req); 605 } 606 607 return VIRTIO_BLK_S_OK; 608 609 err: 610 if (is_write_zeroes) { 611 block_acct_invalid(blk_get_stats(s->blk), BLOCK_ACCT_WRITE); 612 } 613 return err_status; 614 } 615 616 static int virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb) 617 { 618 uint32_t type; 619 struct iovec *in_iov = req->elem.in_sg; 620 struct iovec *out_iov = req->elem.out_sg; 621 unsigned in_num = req->elem.in_num; 622 unsigned out_num = req->elem.out_num; 623 VirtIOBlock *s = req->dev; 624 VirtIODevice *vdev = VIRTIO_DEVICE(s); 625 626 if (req->elem.out_num < 1 || req->elem.in_num < 1) { 627 virtio_error(vdev, "virtio-blk missing headers"); 628 return -1; 629 } 630 631 if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out, 632 sizeof(req->out)) != sizeof(req->out))) { 633 virtio_error(vdev, "virtio-blk request outhdr too short"); 634 return -1; 635 } 636 637 iov_discard_front_undoable(&out_iov, &out_num, sizeof(req->out), 638 &req->outhdr_undo); 639 640 if (in_iov[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) { 641 virtio_error(vdev, "virtio-blk request inhdr too short"); 642 iov_discard_undo(&req->outhdr_undo); 643 return -1; 644 } 645 646 /* We always touch the last byte, so just see how big in_iov is. */ 647 req->in_len = iov_size(in_iov, in_num); 648 req->in = (void *)in_iov[in_num - 1].iov_base 649 + in_iov[in_num - 1].iov_len 650 - sizeof(struct virtio_blk_inhdr); 651 iov_discard_back_undoable(in_iov, &in_num, sizeof(struct virtio_blk_inhdr), 652 &req->inhdr_undo); 653 654 type = virtio_ldl_p(vdev, &req->out.type); 655 656 /* VIRTIO_BLK_T_OUT defines the command direction. VIRTIO_BLK_T_BARRIER 657 * is an optional flag. Although a guest should not send this flag if 658 * not negotiated we ignored it in the past. So keep ignoring it. */ 659 switch (type & ~(VIRTIO_BLK_T_OUT | VIRTIO_BLK_T_BARRIER)) { 660 case VIRTIO_BLK_T_IN: 661 { 662 bool is_write = type & VIRTIO_BLK_T_OUT; 663 req->sector_num = virtio_ldq_p(vdev, &req->out.sector); 664 665 if (is_write) { 666 qemu_iovec_init_external(&req->qiov, out_iov, out_num); 667 trace_virtio_blk_handle_write(vdev, req, req->sector_num, 668 req->qiov.size / BDRV_SECTOR_SIZE); 669 } else { 670 qemu_iovec_init_external(&req->qiov, in_iov, in_num); 671 trace_virtio_blk_handle_read(vdev, req, req->sector_num, 672 req->qiov.size / BDRV_SECTOR_SIZE); 673 } 674 675 if (!virtio_blk_sect_range_ok(s, req->sector_num, req->qiov.size)) { 676 virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR); 677 block_acct_invalid(blk_get_stats(s->blk), 678 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ); 679 virtio_blk_free_request(req); 680 return 0; 681 } 682 683 block_acct_start(blk_get_stats(s->blk), &req->acct, req->qiov.size, 684 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ); 685 686 /* merge would exceed maximum number of requests or IO direction 687 * changes */ 688 if (mrb->num_reqs > 0 && (mrb->num_reqs == VIRTIO_BLK_MAX_MERGE_REQS || 689 is_write != mrb->is_write || 690 !s->conf.request_merging)) { 691 virtio_blk_submit_multireq(s->blk, mrb); 692 } 693 694 assert(mrb->num_reqs < VIRTIO_BLK_MAX_MERGE_REQS); 695 mrb->reqs[mrb->num_reqs++] = req; 696 mrb->is_write = is_write; 697 break; 698 } 699 case VIRTIO_BLK_T_FLUSH: 700 virtio_blk_handle_flush(req, mrb); 701 break; 702 case VIRTIO_BLK_T_SCSI_CMD: 703 virtio_blk_handle_scsi(req); 704 break; 705 case VIRTIO_BLK_T_GET_ID: 706 { 707 /* 708 * NB: per existing s/n string convention the string is 709 * terminated by '\0' only when shorter than buffer. 710 */ 711 const char *serial = s->conf.serial ? s->conf.serial : ""; 712 size_t size = MIN(strlen(serial) + 1, 713 MIN(iov_size(in_iov, in_num), 714 VIRTIO_BLK_ID_BYTES)); 715 iov_from_buf(in_iov, in_num, 0, serial, size); 716 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); 717 virtio_blk_free_request(req); 718 break; 719 } 720 /* 721 * VIRTIO_BLK_T_DISCARD and VIRTIO_BLK_T_WRITE_ZEROES are defined with 722 * VIRTIO_BLK_T_OUT flag set. We masked this flag in the switch statement, 723 * so we must mask it for these requests, then we will check if it is set. 724 */ 725 case VIRTIO_BLK_T_DISCARD & ~VIRTIO_BLK_T_OUT: 726 case VIRTIO_BLK_T_WRITE_ZEROES & ~VIRTIO_BLK_T_OUT: 727 { 728 struct virtio_blk_discard_write_zeroes dwz_hdr; 729 size_t out_len = iov_size(out_iov, out_num); 730 bool is_write_zeroes = (type & ~VIRTIO_BLK_T_BARRIER) == 731 VIRTIO_BLK_T_WRITE_ZEROES; 732 uint8_t err_status; 733 734 /* 735 * Unsupported if VIRTIO_BLK_T_OUT is not set or the request contains 736 * more than one segment. 737 */ 738 if (unlikely(!(type & VIRTIO_BLK_T_OUT) || 739 out_len > sizeof(dwz_hdr))) { 740 virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP); 741 virtio_blk_free_request(req); 742 return 0; 743 } 744 745 if (unlikely(iov_to_buf(out_iov, out_num, 0, &dwz_hdr, 746 sizeof(dwz_hdr)) != sizeof(dwz_hdr))) { 747 iov_discard_undo(&req->inhdr_undo); 748 iov_discard_undo(&req->outhdr_undo); 749 virtio_error(vdev, "virtio-blk discard/write_zeroes header" 750 " too short"); 751 return -1; 752 } 753 754 err_status = virtio_blk_handle_discard_write_zeroes(req, &dwz_hdr, 755 is_write_zeroes); 756 if (err_status != VIRTIO_BLK_S_OK) { 757 virtio_blk_req_complete(req, err_status); 758 virtio_blk_free_request(req); 759 } 760 761 break; 762 } 763 default: 764 virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP); 765 virtio_blk_free_request(req); 766 } 767 return 0; 768 } 769 770 bool virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq) 771 { 772 VirtIOBlockReq *req; 773 MultiReqBuffer mrb = {}; 774 bool suppress_notifications = virtio_queue_get_notification(vq); 775 bool progress = false; 776 777 aio_context_acquire(blk_get_aio_context(s->blk)); 778 blk_io_plug(s->blk); 779 780 do { 781 if (suppress_notifications) { 782 virtio_queue_set_notification(vq, 0); 783 } 784 785 while ((req = virtio_blk_get_request(s, vq))) { 786 progress = true; 787 if (virtio_blk_handle_request(req, &mrb)) { 788 virtqueue_detach_element(req->vq, &req->elem, 0); 789 virtio_blk_free_request(req); 790 break; 791 } 792 } 793 794 if (suppress_notifications) { 795 virtio_queue_set_notification(vq, 1); 796 } 797 } while (!virtio_queue_empty(vq)); 798 799 if (mrb.num_reqs) { 800 virtio_blk_submit_multireq(s->blk, &mrb); 801 } 802 803 blk_io_unplug(s->blk); 804 aio_context_release(blk_get_aio_context(s->blk)); 805 return progress; 806 } 807 808 static void virtio_blk_handle_output_do(VirtIOBlock *s, VirtQueue *vq) 809 { 810 virtio_blk_handle_vq(s, vq); 811 } 812 813 static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq) 814 { 815 VirtIOBlock *s = (VirtIOBlock *)vdev; 816 817 if (s->dataplane) { 818 /* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start 819 * dataplane here instead of waiting for .set_status(). 820 */ 821 virtio_device_start_ioeventfd(vdev); 822 if (!s->dataplane_disabled) { 823 return; 824 } 825 } 826 virtio_blk_handle_output_do(s, vq); 827 } 828 829 void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh) 830 { 831 VirtIOBlockReq *req = s->rq; 832 MultiReqBuffer mrb = {}; 833 834 s->rq = NULL; 835 836 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 837 while (req) { 838 VirtIOBlockReq *next = req->next; 839 if (virtio_blk_handle_request(req, &mrb)) { 840 /* Device is now broken and won't do any processing until it gets 841 * reset. Already queued requests will be lost: let's purge them. 842 */ 843 while (req) { 844 next = req->next; 845 virtqueue_detach_element(req->vq, &req->elem, 0); 846 virtio_blk_free_request(req); 847 req = next; 848 } 849 break; 850 } 851 req = next; 852 } 853 854 if (mrb.num_reqs) { 855 virtio_blk_submit_multireq(s->blk, &mrb); 856 } 857 if (is_bh) { 858 blk_dec_in_flight(s->conf.conf.blk); 859 } 860 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 861 } 862 863 static void virtio_blk_dma_restart_bh(void *opaque) 864 { 865 VirtIOBlock *s = opaque; 866 867 qemu_bh_delete(s->bh); 868 s->bh = NULL; 869 870 virtio_blk_process_queued_requests(s, true); 871 } 872 873 static void virtio_blk_dma_restart_cb(void *opaque, bool running, 874 RunState state) 875 { 876 VirtIOBlock *s = opaque; 877 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s))); 878 VirtioBusState *bus = VIRTIO_BUS(qbus); 879 880 if (!running) { 881 return; 882 } 883 884 /* 885 * If ioeventfd is enabled, don't schedule the BH here as queued 886 * requests will be processed while starting the data plane. 887 */ 888 if (!s->bh && !virtio_bus_ioeventfd_enabled(bus)) { 889 s->bh = aio_bh_new(blk_get_aio_context(s->conf.conf.blk), 890 virtio_blk_dma_restart_bh, s); 891 blk_inc_in_flight(s->conf.conf.blk); 892 qemu_bh_schedule(s->bh); 893 } 894 } 895 896 static void virtio_blk_reset(VirtIODevice *vdev) 897 { 898 VirtIOBlock *s = VIRTIO_BLK(vdev); 899 AioContext *ctx; 900 VirtIOBlockReq *req; 901 902 ctx = blk_get_aio_context(s->blk); 903 aio_context_acquire(ctx); 904 blk_drain(s->blk); 905 906 /* We drop queued requests after blk_drain() because blk_drain() itself can 907 * produce them. */ 908 while (s->rq) { 909 req = s->rq; 910 s->rq = req->next; 911 virtqueue_detach_element(req->vq, &req->elem, 0); 912 virtio_blk_free_request(req); 913 } 914 915 aio_context_release(ctx); 916 917 assert(!s->dataplane_started); 918 blk_set_enable_write_cache(s->blk, s->original_wce); 919 } 920 921 /* coalesce internal state, copy to pci i/o region 0 922 */ 923 static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config) 924 { 925 VirtIOBlock *s = VIRTIO_BLK(vdev); 926 BlockConf *conf = &s->conf.conf; 927 struct virtio_blk_config blkcfg; 928 uint64_t capacity; 929 int64_t length; 930 int blk_size = conf->logical_block_size; 931 932 blk_get_geometry(s->blk, &capacity); 933 memset(&blkcfg, 0, sizeof(blkcfg)); 934 virtio_stq_p(vdev, &blkcfg.capacity, capacity); 935 virtio_stl_p(vdev, &blkcfg.seg_max, 936 s->conf.seg_max_adjust ? s->conf.queue_size - 2 : 128 - 2); 937 virtio_stw_p(vdev, &blkcfg.geometry.cylinders, conf->cyls); 938 virtio_stl_p(vdev, &blkcfg.blk_size, blk_size); 939 virtio_stw_p(vdev, &blkcfg.min_io_size, conf->min_io_size / blk_size); 940 virtio_stl_p(vdev, &blkcfg.opt_io_size, conf->opt_io_size / blk_size); 941 blkcfg.geometry.heads = conf->heads; 942 /* 943 * We must ensure that the block device capacity is a multiple of 944 * the logical block size. If that is not the case, let's use 945 * sector_mask to adopt the geometry to have a correct picture. 946 * For those devices where the capacity is ok for the given geometry 947 * we don't touch the sector value of the geometry, since some devices 948 * (like s390 dasd) need a specific value. Here the capacity is already 949 * cyls*heads*secs*blk_size and the sector value is not block size 950 * divided by 512 - instead it is the amount of blk_size blocks 951 * per track (cylinder). 952 */ 953 length = blk_getlength(s->blk); 954 if (length > 0 && length / conf->heads / conf->secs % blk_size) { 955 blkcfg.geometry.sectors = conf->secs & ~s->sector_mask; 956 } else { 957 blkcfg.geometry.sectors = conf->secs; 958 } 959 blkcfg.size_max = 0; 960 blkcfg.physical_block_exp = get_physical_block_exp(conf); 961 blkcfg.alignment_offset = 0; 962 blkcfg.wce = blk_enable_write_cache(s->blk); 963 virtio_stw_p(vdev, &blkcfg.num_queues, s->conf.num_queues); 964 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD)) { 965 uint32_t discard_granularity = conf->discard_granularity; 966 if (discard_granularity == -1 || !s->conf.report_discard_granularity) { 967 discard_granularity = blk_size; 968 } 969 virtio_stl_p(vdev, &blkcfg.max_discard_sectors, 970 s->conf.max_discard_sectors); 971 virtio_stl_p(vdev, &blkcfg.discard_sector_alignment, 972 discard_granularity >> BDRV_SECTOR_BITS); 973 /* 974 * We support only one segment per request since multiple segments 975 * are not widely used and there are no userspace APIs that allow 976 * applications to submit multiple segments in a single call. 977 */ 978 virtio_stl_p(vdev, &blkcfg.max_discard_seg, 1); 979 } 980 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES)) { 981 virtio_stl_p(vdev, &blkcfg.max_write_zeroes_sectors, 982 s->conf.max_write_zeroes_sectors); 983 blkcfg.write_zeroes_may_unmap = 1; 984 virtio_stl_p(vdev, &blkcfg.max_write_zeroes_seg, 1); 985 } 986 memcpy(config, &blkcfg, s->config_size); 987 } 988 989 static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config) 990 { 991 VirtIOBlock *s = VIRTIO_BLK(vdev); 992 struct virtio_blk_config blkcfg; 993 994 memcpy(&blkcfg, config, s->config_size); 995 996 aio_context_acquire(blk_get_aio_context(s->blk)); 997 blk_set_enable_write_cache(s->blk, blkcfg.wce != 0); 998 aio_context_release(blk_get_aio_context(s->blk)); 999 } 1000 1001 static uint64_t virtio_blk_get_features(VirtIODevice *vdev, uint64_t features, 1002 Error **errp) 1003 { 1004 VirtIOBlock *s = VIRTIO_BLK(vdev); 1005 1006 /* Firstly sync all virtio-blk possible supported features */ 1007 features |= s->host_features; 1008 1009 virtio_add_feature(&features, VIRTIO_BLK_F_SEG_MAX); 1010 virtio_add_feature(&features, VIRTIO_BLK_F_GEOMETRY); 1011 virtio_add_feature(&features, VIRTIO_BLK_F_TOPOLOGY); 1012 virtio_add_feature(&features, VIRTIO_BLK_F_BLK_SIZE); 1013 if (virtio_has_feature(features, VIRTIO_F_VERSION_1)) { 1014 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_SCSI)) { 1015 error_setg(errp, "Please set scsi=off for virtio-blk devices in order to use virtio 1.0"); 1016 return 0; 1017 } 1018 } else { 1019 virtio_clear_feature(&features, VIRTIO_F_ANY_LAYOUT); 1020 virtio_add_feature(&features, VIRTIO_BLK_F_SCSI); 1021 } 1022 1023 if (blk_enable_write_cache(s->blk) || 1024 (s->conf.x_enable_wce_if_config_wce && 1025 virtio_has_feature(features, VIRTIO_BLK_F_CONFIG_WCE))) { 1026 virtio_add_feature(&features, VIRTIO_BLK_F_WCE); 1027 } 1028 if (!blk_is_writable(s->blk)) { 1029 virtio_add_feature(&features, VIRTIO_BLK_F_RO); 1030 } 1031 if (s->conf.num_queues > 1) { 1032 virtio_add_feature(&features, VIRTIO_BLK_F_MQ); 1033 } 1034 1035 return features; 1036 } 1037 1038 static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status) 1039 { 1040 VirtIOBlock *s = VIRTIO_BLK(vdev); 1041 1042 if (!(status & (VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK))) { 1043 assert(!s->dataplane_started); 1044 } 1045 1046 if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) { 1047 return; 1048 } 1049 1050 /* A guest that supports VIRTIO_BLK_F_CONFIG_WCE must be able to send 1051 * cache flushes. Thus, the "auto writethrough" behavior is never 1052 * necessary for guests that support the VIRTIO_BLK_F_CONFIG_WCE feature. 1053 * Leaving it enabled would break the following sequence: 1054 * 1055 * Guest started with "-drive cache=writethrough" 1056 * Guest sets status to 0 1057 * Guest sets DRIVER bit in status field 1058 * Guest reads host features (WCE=0, CONFIG_WCE=1) 1059 * Guest writes guest features (WCE=0, CONFIG_WCE=1) 1060 * Guest writes 1 to the WCE configuration field (writeback mode) 1061 * Guest sets DRIVER_OK bit in status field 1062 * 1063 * s->blk would erroneously be placed in writethrough mode. 1064 */ 1065 if (!virtio_vdev_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE)) { 1066 aio_context_acquire(blk_get_aio_context(s->blk)); 1067 blk_set_enable_write_cache(s->blk, 1068 virtio_vdev_has_feature(vdev, 1069 VIRTIO_BLK_F_WCE)); 1070 aio_context_release(blk_get_aio_context(s->blk)); 1071 } 1072 } 1073 1074 static void virtio_blk_save_device(VirtIODevice *vdev, QEMUFile *f) 1075 { 1076 VirtIOBlock *s = VIRTIO_BLK(vdev); 1077 VirtIOBlockReq *req = s->rq; 1078 1079 while (req) { 1080 qemu_put_sbyte(f, 1); 1081 1082 if (s->conf.num_queues > 1) { 1083 qemu_put_be32(f, virtio_get_queue_index(req->vq)); 1084 } 1085 1086 qemu_put_virtqueue_element(vdev, f, &req->elem); 1087 req = req->next; 1088 } 1089 qemu_put_sbyte(f, 0); 1090 } 1091 1092 static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f, 1093 int version_id) 1094 { 1095 VirtIOBlock *s = VIRTIO_BLK(vdev); 1096 1097 while (qemu_get_sbyte(f)) { 1098 unsigned nvqs = s->conf.num_queues; 1099 unsigned vq_idx = 0; 1100 VirtIOBlockReq *req; 1101 1102 if (nvqs > 1) { 1103 vq_idx = qemu_get_be32(f); 1104 1105 if (vq_idx >= nvqs) { 1106 error_report("Invalid virtqueue index in request list: %#x", 1107 vq_idx); 1108 return -EINVAL; 1109 } 1110 } 1111 1112 req = qemu_get_virtqueue_element(vdev, f, sizeof(VirtIOBlockReq)); 1113 virtio_blk_init_request(s, virtio_get_queue(vdev, vq_idx), req); 1114 req->next = s->rq; 1115 s->rq = req; 1116 } 1117 1118 return 0; 1119 } 1120 1121 static void virtio_resize_cb(void *opaque) 1122 { 1123 VirtIODevice *vdev = opaque; 1124 1125 assert(qemu_get_current_aio_context() == qemu_get_aio_context()); 1126 virtio_notify_config(vdev); 1127 } 1128 1129 static void virtio_blk_resize(void *opaque) 1130 { 1131 VirtIODevice *vdev = VIRTIO_DEVICE(opaque); 1132 1133 /* 1134 * virtio_notify_config() needs to acquire the global mutex, 1135 * so it can't be called from an iothread. Instead, schedule 1136 * it to be run in the main context BH. 1137 */ 1138 aio_bh_schedule_oneshot(qemu_get_aio_context(), virtio_resize_cb, vdev); 1139 } 1140 1141 static const BlockDevOps virtio_block_ops = { 1142 .resize_cb = virtio_blk_resize, 1143 }; 1144 1145 static void virtio_blk_device_realize(DeviceState *dev, Error **errp) 1146 { 1147 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 1148 VirtIOBlock *s = VIRTIO_BLK(dev); 1149 VirtIOBlkConf *conf = &s->conf; 1150 Error *err = NULL; 1151 unsigned i; 1152 1153 if (!conf->conf.blk) { 1154 error_setg(errp, "drive property not set"); 1155 return; 1156 } 1157 if (!blk_is_inserted(conf->conf.blk)) { 1158 error_setg(errp, "Device needs media, but drive is empty"); 1159 return; 1160 } 1161 if (conf->num_queues == VIRTIO_BLK_AUTO_NUM_QUEUES) { 1162 conf->num_queues = 1; 1163 } 1164 if (!conf->num_queues) { 1165 error_setg(errp, "num-queues property must be larger than 0"); 1166 return; 1167 } 1168 if (conf->queue_size <= 2) { 1169 error_setg(errp, "invalid queue-size property (%" PRIu16 "), " 1170 "must be > 2", conf->queue_size); 1171 return; 1172 } 1173 if (!is_power_of_2(conf->queue_size) || 1174 conf->queue_size > VIRTQUEUE_MAX_SIZE) { 1175 error_setg(errp, "invalid queue-size property (%" PRIu16 "), " 1176 "must be a power of 2 (max %d)", 1177 conf->queue_size, VIRTQUEUE_MAX_SIZE); 1178 return; 1179 } 1180 1181 if (!blkconf_apply_backend_options(&conf->conf, 1182 !blk_supports_write_perm(conf->conf.blk), 1183 true, errp)) { 1184 return; 1185 } 1186 s->original_wce = blk_enable_write_cache(conf->conf.blk); 1187 if (!blkconf_geometry(&conf->conf, NULL, 65535, 255, 255, errp)) { 1188 return; 1189 } 1190 1191 if (!blkconf_blocksizes(&conf->conf, errp)) { 1192 return; 1193 } 1194 1195 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD) && 1196 (!conf->max_discard_sectors || 1197 conf->max_discard_sectors > BDRV_REQUEST_MAX_SECTORS)) { 1198 error_setg(errp, "invalid max-discard-sectors property (%" PRIu32 ")" 1199 ", must be between 1 and %d", 1200 conf->max_discard_sectors, (int)BDRV_REQUEST_MAX_SECTORS); 1201 return; 1202 } 1203 1204 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES) && 1205 (!conf->max_write_zeroes_sectors || 1206 conf->max_write_zeroes_sectors > BDRV_REQUEST_MAX_SECTORS)) { 1207 error_setg(errp, "invalid max-write-zeroes-sectors property (%" PRIu32 1208 "), must be between 1 and %d", 1209 conf->max_write_zeroes_sectors, 1210 (int)BDRV_REQUEST_MAX_SECTORS); 1211 return; 1212 } 1213 1214 virtio_blk_set_config_size(s, s->host_features); 1215 1216 virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, s->config_size); 1217 1218 s->blk = conf->conf.blk; 1219 s->rq = NULL; 1220 s->sector_mask = (s->conf.conf.logical_block_size / BDRV_SECTOR_SIZE) - 1; 1221 1222 for (i = 0; i < conf->num_queues; i++) { 1223 virtio_add_queue(vdev, conf->queue_size, virtio_blk_handle_output); 1224 } 1225 virtio_blk_data_plane_create(vdev, conf, &s->dataplane, &err); 1226 if (err != NULL) { 1227 error_propagate(errp, err); 1228 for (i = 0; i < conf->num_queues; i++) { 1229 virtio_del_queue(vdev, i); 1230 } 1231 virtio_cleanup(vdev); 1232 return; 1233 } 1234 1235 s->change = qemu_add_vm_change_state_handler(virtio_blk_dma_restart_cb, s); 1236 blk_set_dev_ops(s->blk, &virtio_block_ops, s); 1237 blk_set_guest_block_size(s->blk, s->conf.conf.logical_block_size); 1238 1239 blk_iostatus_enable(s->blk); 1240 1241 add_boot_device_lchs(dev, "/disk@0,0", 1242 conf->conf.lcyls, 1243 conf->conf.lheads, 1244 conf->conf.lsecs); 1245 } 1246 1247 static void virtio_blk_device_unrealize(DeviceState *dev) 1248 { 1249 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 1250 VirtIOBlock *s = VIRTIO_BLK(dev); 1251 VirtIOBlkConf *conf = &s->conf; 1252 unsigned i; 1253 1254 blk_drain(s->blk); 1255 del_boot_device_lchs(dev, "/disk@0,0"); 1256 virtio_blk_data_plane_destroy(s->dataplane); 1257 s->dataplane = NULL; 1258 for (i = 0; i < conf->num_queues; i++) { 1259 virtio_del_queue(vdev, i); 1260 } 1261 qemu_del_vm_change_state_handler(s->change); 1262 blockdev_mark_auto_del(s->blk); 1263 virtio_cleanup(vdev); 1264 } 1265 1266 static void virtio_blk_instance_init(Object *obj) 1267 { 1268 VirtIOBlock *s = VIRTIO_BLK(obj); 1269 1270 device_add_bootindex_property(obj, &s->conf.conf.bootindex, 1271 "bootindex", "/disk@0,0", 1272 DEVICE(obj)); 1273 } 1274 1275 static const VMStateDescription vmstate_virtio_blk = { 1276 .name = "virtio-blk", 1277 .minimum_version_id = 2, 1278 .version_id = 2, 1279 .fields = (VMStateField[]) { 1280 VMSTATE_VIRTIO_DEVICE, 1281 VMSTATE_END_OF_LIST() 1282 }, 1283 }; 1284 1285 static Property virtio_blk_properties[] = { 1286 DEFINE_BLOCK_PROPERTIES(VirtIOBlock, conf.conf), 1287 DEFINE_BLOCK_ERROR_PROPERTIES(VirtIOBlock, conf.conf), 1288 DEFINE_BLOCK_CHS_PROPERTIES(VirtIOBlock, conf.conf), 1289 DEFINE_PROP_STRING("serial", VirtIOBlock, conf.serial), 1290 DEFINE_PROP_BIT64("config-wce", VirtIOBlock, host_features, 1291 VIRTIO_BLK_F_CONFIG_WCE, true), 1292 #ifdef __linux__ 1293 DEFINE_PROP_BIT64("scsi", VirtIOBlock, host_features, 1294 VIRTIO_BLK_F_SCSI, false), 1295 #endif 1296 DEFINE_PROP_BIT("request-merging", VirtIOBlock, conf.request_merging, 0, 1297 true), 1298 DEFINE_PROP_UINT16("num-queues", VirtIOBlock, conf.num_queues, 1299 VIRTIO_BLK_AUTO_NUM_QUEUES), 1300 DEFINE_PROP_UINT16("queue-size", VirtIOBlock, conf.queue_size, 256), 1301 DEFINE_PROP_BOOL("seg-max-adjust", VirtIOBlock, conf.seg_max_adjust, true), 1302 DEFINE_PROP_LINK("iothread", VirtIOBlock, conf.iothread, TYPE_IOTHREAD, 1303 IOThread *), 1304 DEFINE_PROP_BIT64("discard", VirtIOBlock, host_features, 1305 VIRTIO_BLK_F_DISCARD, true), 1306 DEFINE_PROP_BOOL("report-discard-granularity", VirtIOBlock, 1307 conf.report_discard_granularity, true), 1308 DEFINE_PROP_BIT64("write-zeroes", VirtIOBlock, host_features, 1309 VIRTIO_BLK_F_WRITE_ZEROES, true), 1310 DEFINE_PROP_UINT32("max-discard-sectors", VirtIOBlock, 1311 conf.max_discard_sectors, BDRV_REQUEST_MAX_SECTORS), 1312 DEFINE_PROP_UINT32("max-write-zeroes-sectors", VirtIOBlock, 1313 conf.max_write_zeroes_sectors, BDRV_REQUEST_MAX_SECTORS), 1314 DEFINE_PROP_BOOL("x-enable-wce-if-config-wce", VirtIOBlock, 1315 conf.x_enable_wce_if_config_wce, true), 1316 DEFINE_PROP_END_OF_LIST(), 1317 }; 1318 1319 static void virtio_blk_class_init(ObjectClass *klass, void *data) 1320 { 1321 DeviceClass *dc = DEVICE_CLASS(klass); 1322 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 1323 1324 device_class_set_props(dc, virtio_blk_properties); 1325 dc->vmsd = &vmstate_virtio_blk; 1326 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 1327 vdc->realize = virtio_blk_device_realize; 1328 vdc->unrealize = virtio_blk_device_unrealize; 1329 vdc->get_config = virtio_blk_update_config; 1330 vdc->set_config = virtio_blk_set_config; 1331 vdc->get_features = virtio_blk_get_features; 1332 vdc->set_status = virtio_blk_set_status; 1333 vdc->reset = virtio_blk_reset; 1334 vdc->save = virtio_blk_save_device; 1335 vdc->load = virtio_blk_load_device; 1336 vdc->start_ioeventfd = virtio_blk_data_plane_start; 1337 vdc->stop_ioeventfd = virtio_blk_data_plane_stop; 1338 } 1339 1340 static const TypeInfo virtio_blk_info = { 1341 .name = TYPE_VIRTIO_BLK, 1342 .parent = TYPE_VIRTIO_DEVICE, 1343 .instance_size = sizeof(VirtIOBlock), 1344 .instance_init = virtio_blk_instance_init, 1345 .class_init = virtio_blk_class_init, 1346 }; 1347 1348 static void virtio_register_types(void) 1349 { 1350 type_register_static(&virtio_blk_info); 1351 } 1352 1353 type_init(virtio_register_types) 1354