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