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