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