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 void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh) 810 { 811 VirtIOBlockReq *req = s->rq; 812 MultiReqBuffer mrb = {}; 813 814 s->rq = NULL; 815 816 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 817 while (req) { 818 VirtIOBlockReq *next = req->next; 819 if (virtio_blk_handle_request(req, &mrb)) { 820 /* Device is now broken and won't do any processing until it gets 821 * reset. Already queued requests will be lost: let's purge them. 822 */ 823 while (req) { 824 next = req->next; 825 virtqueue_detach_element(req->vq, &req->elem, 0); 826 virtio_blk_free_request(req); 827 req = next; 828 } 829 break; 830 } 831 req = next; 832 } 833 834 if (mrb.num_reqs) { 835 virtio_blk_submit_multireq(s, &mrb); 836 } 837 if (is_bh) { 838 blk_dec_in_flight(s->conf.conf.blk); 839 } 840 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 841 } 842 843 static void virtio_blk_dma_restart_bh(void *opaque) 844 { 845 VirtIOBlock *s = opaque; 846 847 qemu_bh_delete(s->bh); 848 s->bh = NULL; 849 850 virtio_blk_process_queued_requests(s, true); 851 } 852 853 static void virtio_blk_dma_restart_cb(void *opaque, bool running, 854 RunState state) 855 { 856 VirtIOBlock *s = opaque; 857 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s))); 858 VirtioBusState *bus = VIRTIO_BUS(qbus); 859 860 if (!running) { 861 return; 862 } 863 864 /* 865 * If ioeventfd is enabled, don't schedule the BH here as queued 866 * requests will be processed while starting the data plane. 867 */ 868 if (!s->bh && !virtio_bus_ioeventfd_enabled(bus)) { 869 s->bh = aio_bh_new(blk_get_aio_context(s->conf.conf.blk), 870 virtio_blk_dma_restart_bh, s); 871 blk_inc_in_flight(s->conf.conf.blk); 872 qemu_bh_schedule(s->bh); 873 } 874 } 875 876 static void virtio_blk_reset(VirtIODevice *vdev) 877 { 878 VirtIOBlock *s = VIRTIO_BLK(vdev); 879 AioContext *ctx; 880 VirtIOBlockReq *req; 881 882 ctx = blk_get_aio_context(s->blk); 883 aio_context_acquire(ctx); 884 blk_drain(s->blk); 885 886 /* We drop queued requests after blk_drain() because blk_drain() itself can 887 * produce them. */ 888 while (s->rq) { 889 req = s->rq; 890 s->rq = req->next; 891 virtqueue_detach_element(req->vq, &req->elem, 0); 892 virtio_blk_free_request(req); 893 } 894 895 aio_context_release(ctx); 896 897 assert(!s->dataplane_started); 898 blk_set_enable_write_cache(s->blk, s->original_wce); 899 } 900 901 /* coalesce internal state, copy to pci i/o region 0 902 */ 903 static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config) 904 { 905 VirtIOBlock *s = VIRTIO_BLK(vdev); 906 BlockConf *conf = &s->conf.conf; 907 struct virtio_blk_config blkcfg; 908 uint64_t capacity; 909 int64_t length; 910 int blk_size = conf->logical_block_size; 911 912 blk_get_geometry(s->blk, &capacity); 913 memset(&blkcfg, 0, sizeof(blkcfg)); 914 virtio_stq_p(vdev, &blkcfg.capacity, capacity); 915 virtio_stl_p(vdev, &blkcfg.seg_max, 916 s->conf.seg_max_adjust ? s->conf.queue_size - 2 : 128 - 2); 917 virtio_stw_p(vdev, &blkcfg.geometry.cylinders, conf->cyls); 918 virtio_stl_p(vdev, &blkcfg.blk_size, blk_size); 919 virtio_stw_p(vdev, &blkcfg.min_io_size, conf->min_io_size / blk_size); 920 virtio_stl_p(vdev, &blkcfg.opt_io_size, conf->opt_io_size / blk_size); 921 blkcfg.geometry.heads = conf->heads; 922 /* 923 * We must ensure that the block device capacity is a multiple of 924 * the logical block size. If that is not the case, let's use 925 * sector_mask to adopt the geometry to have a correct picture. 926 * For those devices where the capacity is ok for the given geometry 927 * we don't touch the sector value of the geometry, since some devices 928 * (like s390 dasd) need a specific value. Here the capacity is already 929 * cyls*heads*secs*blk_size and the sector value is not block size 930 * divided by 512 - instead it is the amount of blk_size blocks 931 * per track (cylinder). 932 */ 933 length = blk_getlength(s->blk); 934 if (length > 0 && length / conf->heads / conf->secs % blk_size) { 935 blkcfg.geometry.sectors = conf->secs & ~s->sector_mask; 936 } else { 937 blkcfg.geometry.sectors = conf->secs; 938 } 939 blkcfg.size_max = 0; 940 blkcfg.physical_block_exp = get_physical_block_exp(conf); 941 blkcfg.alignment_offset = 0; 942 blkcfg.wce = blk_enable_write_cache(s->blk); 943 virtio_stw_p(vdev, &blkcfg.num_queues, s->conf.num_queues); 944 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD)) { 945 uint32_t discard_granularity = conf->discard_granularity; 946 if (discard_granularity == -1 || !s->conf.report_discard_granularity) { 947 discard_granularity = blk_size; 948 } 949 virtio_stl_p(vdev, &blkcfg.max_discard_sectors, 950 s->conf.max_discard_sectors); 951 virtio_stl_p(vdev, &blkcfg.discard_sector_alignment, 952 discard_granularity >> BDRV_SECTOR_BITS); 953 /* 954 * We support only one segment per request since multiple segments 955 * are not widely used and there are no userspace APIs that allow 956 * applications to submit multiple segments in a single call. 957 */ 958 virtio_stl_p(vdev, &blkcfg.max_discard_seg, 1); 959 } 960 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES)) { 961 virtio_stl_p(vdev, &blkcfg.max_write_zeroes_sectors, 962 s->conf.max_write_zeroes_sectors); 963 blkcfg.write_zeroes_may_unmap = 1; 964 virtio_stl_p(vdev, &blkcfg.max_write_zeroes_seg, 1); 965 } 966 memcpy(config, &blkcfg, s->config_size); 967 } 968 969 static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config) 970 { 971 VirtIOBlock *s = VIRTIO_BLK(vdev); 972 struct virtio_blk_config blkcfg; 973 974 memcpy(&blkcfg, config, s->config_size); 975 976 aio_context_acquire(blk_get_aio_context(s->blk)); 977 blk_set_enable_write_cache(s->blk, blkcfg.wce != 0); 978 aio_context_release(blk_get_aio_context(s->blk)); 979 } 980 981 static uint64_t virtio_blk_get_features(VirtIODevice *vdev, uint64_t features, 982 Error **errp) 983 { 984 VirtIOBlock *s = VIRTIO_BLK(vdev); 985 986 /* Firstly sync all virtio-blk possible supported features */ 987 features |= s->host_features; 988 989 virtio_add_feature(&features, VIRTIO_BLK_F_SEG_MAX); 990 virtio_add_feature(&features, VIRTIO_BLK_F_GEOMETRY); 991 virtio_add_feature(&features, VIRTIO_BLK_F_TOPOLOGY); 992 virtio_add_feature(&features, VIRTIO_BLK_F_BLK_SIZE); 993 if (virtio_has_feature(features, VIRTIO_F_VERSION_1)) { 994 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_SCSI)) { 995 error_setg(errp, "Please set scsi=off for virtio-blk devices in order to use virtio 1.0"); 996 return 0; 997 } 998 } else { 999 virtio_clear_feature(&features, VIRTIO_F_ANY_LAYOUT); 1000 virtio_add_feature(&features, VIRTIO_BLK_F_SCSI); 1001 } 1002 1003 if (blk_enable_write_cache(s->blk) || 1004 (s->conf.x_enable_wce_if_config_wce && 1005 virtio_has_feature(features, VIRTIO_BLK_F_CONFIG_WCE))) { 1006 virtio_add_feature(&features, VIRTIO_BLK_F_WCE); 1007 } 1008 if (!blk_is_writable(s->blk)) { 1009 virtio_add_feature(&features, VIRTIO_BLK_F_RO); 1010 } 1011 if (s->conf.num_queues > 1) { 1012 virtio_add_feature(&features, VIRTIO_BLK_F_MQ); 1013 } 1014 1015 return features; 1016 } 1017 1018 static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status) 1019 { 1020 VirtIOBlock *s = VIRTIO_BLK(vdev); 1021 1022 if (!(status & (VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK))) { 1023 assert(!s->dataplane_started); 1024 } 1025 1026 if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) { 1027 return; 1028 } 1029 1030 /* A guest that supports VIRTIO_BLK_F_CONFIG_WCE must be able to send 1031 * cache flushes. Thus, the "auto writethrough" behavior is never 1032 * necessary for guests that support the VIRTIO_BLK_F_CONFIG_WCE feature. 1033 * Leaving it enabled would break the following sequence: 1034 * 1035 * Guest started with "-drive cache=writethrough" 1036 * Guest sets status to 0 1037 * Guest sets DRIVER bit in status field 1038 * Guest reads host features (WCE=0, CONFIG_WCE=1) 1039 * Guest writes guest features (WCE=0, CONFIG_WCE=1) 1040 * Guest writes 1 to the WCE configuration field (writeback mode) 1041 * Guest sets DRIVER_OK bit in status field 1042 * 1043 * s->blk would erroneously be placed in writethrough mode. 1044 */ 1045 if (!virtio_vdev_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE)) { 1046 aio_context_acquire(blk_get_aio_context(s->blk)); 1047 blk_set_enable_write_cache(s->blk, 1048 virtio_vdev_has_feature(vdev, 1049 VIRTIO_BLK_F_WCE)); 1050 aio_context_release(blk_get_aio_context(s->blk)); 1051 } 1052 } 1053 1054 static void virtio_blk_save_device(VirtIODevice *vdev, QEMUFile *f) 1055 { 1056 VirtIOBlock *s = VIRTIO_BLK(vdev); 1057 VirtIOBlockReq *req = s->rq; 1058 1059 while (req) { 1060 qemu_put_sbyte(f, 1); 1061 1062 if (s->conf.num_queues > 1) { 1063 qemu_put_be32(f, virtio_get_queue_index(req->vq)); 1064 } 1065 1066 qemu_put_virtqueue_element(vdev, f, &req->elem); 1067 req = req->next; 1068 } 1069 qemu_put_sbyte(f, 0); 1070 } 1071 1072 static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f, 1073 int version_id) 1074 { 1075 VirtIOBlock *s = VIRTIO_BLK(vdev); 1076 1077 while (qemu_get_sbyte(f)) { 1078 unsigned nvqs = s->conf.num_queues; 1079 unsigned vq_idx = 0; 1080 VirtIOBlockReq *req; 1081 1082 if (nvqs > 1) { 1083 vq_idx = qemu_get_be32(f); 1084 1085 if (vq_idx >= nvqs) { 1086 error_report("Invalid virtqueue index in request list: %#x", 1087 vq_idx); 1088 return -EINVAL; 1089 } 1090 } 1091 1092 req = qemu_get_virtqueue_element(vdev, f, sizeof(VirtIOBlockReq)); 1093 virtio_blk_init_request(s, virtio_get_queue(vdev, vq_idx), req); 1094 req->next = s->rq; 1095 s->rq = req; 1096 } 1097 1098 return 0; 1099 } 1100 1101 static void virtio_resize_cb(void *opaque) 1102 { 1103 VirtIODevice *vdev = opaque; 1104 1105 assert(qemu_get_current_aio_context() == qemu_get_aio_context()); 1106 virtio_notify_config(vdev); 1107 } 1108 1109 static void virtio_blk_resize(void *opaque) 1110 { 1111 VirtIODevice *vdev = VIRTIO_DEVICE(opaque); 1112 1113 /* 1114 * virtio_notify_config() needs to acquire the global mutex, 1115 * so it can't be called from an iothread. Instead, schedule 1116 * it to be run in the main context BH. 1117 */ 1118 aio_bh_schedule_oneshot(qemu_get_aio_context(), virtio_resize_cb, vdev); 1119 } 1120 1121 static const BlockDevOps virtio_block_ops = { 1122 .resize_cb = virtio_blk_resize, 1123 }; 1124 1125 static void virtio_blk_device_realize(DeviceState *dev, Error **errp) 1126 { 1127 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 1128 VirtIOBlock *s = VIRTIO_BLK(dev); 1129 VirtIOBlkConf *conf = &s->conf; 1130 Error *err = NULL; 1131 unsigned i; 1132 1133 if (!conf->conf.blk) { 1134 error_setg(errp, "drive property not set"); 1135 return; 1136 } 1137 if (!blk_is_inserted(conf->conf.blk)) { 1138 error_setg(errp, "Device needs media, but drive is empty"); 1139 return; 1140 } 1141 if (conf->num_queues == VIRTIO_BLK_AUTO_NUM_QUEUES) { 1142 conf->num_queues = 1; 1143 } 1144 if (!conf->num_queues) { 1145 error_setg(errp, "num-queues property must be larger than 0"); 1146 return; 1147 } 1148 if (conf->queue_size <= 2) { 1149 error_setg(errp, "invalid queue-size property (%" PRIu16 "), " 1150 "must be > 2", conf->queue_size); 1151 return; 1152 } 1153 if (!is_power_of_2(conf->queue_size) || 1154 conf->queue_size > VIRTQUEUE_MAX_SIZE) { 1155 error_setg(errp, "invalid queue-size property (%" PRIu16 "), " 1156 "must be a power of 2 (max %d)", 1157 conf->queue_size, VIRTQUEUE_MAX_SIZE); 1158 return; 1159 } 1160 1161 if (!blkconf_apply_backend_options(&conf->conf, 1162 !blk_supports_write_perm(conf->conf.blk), 1163 true, errp)) { 1164 return; 1165 } 1166 s->original_wce = blk_enable_write_cache(conf->conf.blk); 1167 if (!blkconf_geometry(&conf->conf, NULL, 65535, 255, 255, errp)) { 1168 return; 1169 } 1170 1171 if (!blkconf_blocksizes(&conf->conf, errp)) { 1172 return; 1173 } 1174 1175 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD) && 1176 (!conf->max_discard_sectors || 1177 conf->max_discard_sectors > BDRV_REQUEST_MAX_SECTORS)) { 1178 error_setg(errp, "invalid max-discard-sectors property (%" PRIu32 ")" 1179 ", must be between 1 and %d", 1180 conf->max_discard_sectors, (int)BDRV_REQUEST_MAX_SECTORS); 1181 return; 1182 } 1183 1184 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES) && 1185 (!conf->max_write_zeroes_sectors || 1186 conf->max_write_zeroes_sectors > BDRV_REQUEST_MAX_SECTORS)) { 1187 error_setg(errp, "invalid max-write-zeroes-sectors property (%" PRIu32 1188 "), must be between 1 and %d", 1189 conf->max_write_zeroes_sectors, 1190 (int)BDRV_REQUEST_MAX_SECTORS); 1191 return; 1192 } 1193 1194 s->config_size = virtio_get_config_size(&virtio_blk_cfg_size_params, 1195 s->host_features); 1196 virtio_init(vdev, VIRTIO_ID_BLOCK, s->config_size); 1197 1198 s->blk = conf->conf.blk; 1199 s->rq = NULL; 1200 s->sector_mask = (s->conf.conf.logical_block_size / BDRV_SECTOR_SIZE) - 1; 1201 1202 for (i = 0; i < conf->num_queues; i++) { 1203 virtio_add_queue(vdev, conf->queue_size, virtio_blk_handle_output); 1204 } 1205 qemu_coroutine_inc_pool_size(conf->num_queues * conf->queue_size / 2); 1206 virtio_blk_data_plane_create(vdev, conf, &s->dataplane, &err); 1207 if (err != NULL) { 1208 error_propagate(errp, err); 1209 for (i = 0; i < conf->num_queues; i++) { 1210 virtio_del_queue(vdev, i); 1211 } 1212 virtio_cleanup(vdev); 1213 return; 1214 } 1215 1216 s->change = qemu_add_vm_change_state_handler(virtio_blk_dma_restart_cb, s); 1217 blk_ram_registrar_init(&s->blk_ram_registrar, s->blk); 1218 blk_set_dev_ops(s->blk, &virtio_block_ops, s); 1219 1220 blk_iostatus_enable(s->blk); 1221 1222 add_boot_device_lchs(dev, "/disk@0,0", 1223 conf->conf.lcyls, 1224 conf->conf.lheads, 1225 conf->conf.lsecs); 1226 } 1227 1228 static void virtio_blk_device_unrealize(DeviceState *dev) 1229 { 1230 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 1231 VirtIOBlock *s = VIRTIO_BLK(dev); 1232 VirtIOBlkConf *conf = &s->conf; 1233 unsigned i; 1234 1235 blk_drain(s->blk); 1236 del_boot_device_lchs(dev, "/disk@0,0"); 1237 virtio_blk_data_plane_destroy(s->dataplane); 1238 s->dataplane = NULL; 1239 for (i = 0; i < conf->num_queues; i++) { 1240 virtio_del_queue(vdev, i); 1241 } 1242 qemu_coroutine_dec_pool_size(conf->num_queues * conf->queue_size / 2); 1243 blk_ram_registrar_destroy(&s->blk_ram_registrar); 1244 qemu_del_vm_change_state_handler(s->change); 1245 blockdev_mark_auto_del(s->blk); 1246 virtio_cleanup(vdev); 1247 } 1248 1249 static void virtio_blk_instance_init(Object *obj) 1250 { 1251 VirtIOBlock *s = VIRTIO_BLK(obj); 1252 1253 device_add_bootindex_property(obj, &s->conf.conf.bootindex, 1254 "bootindex", "/disk@0,0", 1255 DEVICE(obj)); 1256 } 1257 1258 static const VMStateDescription vmstate_virtio_blk = { 1259 .name = "virtio-blk", 1260 .minimum_version_id = 2, 1261 .version_id = 2, 1262 .fields = (VMStateField[]) { 1263 VMSTATE_VIRTIO_DEVICE, 1264 VMSTATE_END_OF_LIST() 1265 }, 1266 }; 1267 1268 static Property virtio_blk_properties[] = { 1269 DEFINE_BLOCK_PROPERTIES(VirtIOBlock, conf.conf), 1270 DEFINE_BLOCK_ERROR_PROPERTIES(VirtIOBlock, conf.conf), 1271 DEFINE_BLOCK_CHS_PROPERTIES(VirtIOBlock, conf.conf), 1272 DEFINE_PROP_STRING("serial", VirtIOBlock, conf.serial), 1273 DEFINE_PROP_BIT64("config-wce", VirtIOBlock, host_features, 1274 VIRTIO_BLK_F_CONFIG_WCE, true), 1275 #ifdef __linux__ 1276 DEFINE_PROP_BIT64("scsi", VirtIOBlock, host_features, 1277 VIRTIO_BLK_F_SCSI, false), 1278 #endif 1279 DEFINE_PROP_BIT("request-merging", VirtIOBlock, conf.request_merging, 0, 1280 true), 1281 DEFINE_PROP_UINT16("num-queues", VirtIOBlock, conf.num_queues, 1282 VIRTIO_BLK_AUTO_NUM_QUEUES), 1283 DEFINE_PROP_UINT16("queue-size", VirtIOBlock, conf.queue_size, 256), 1284 DEFINE_PROP_BOOL("seg-max-adjust", VirtIOBlock, conf.seg_max_adjust, true), 1285 DEFINE_PROP_LINK("iothread", VirtIOBlock, conf.iothread, TYPE_IOTHREAD, 1286 IOThread *), 1287 DEFINE_PROP_BIT64("discard", VirtIOBlock, host_features, 1288 VIRTIO_BLK_F_DISCARD, true), 1289 DEFINE_PROP_BOOL("report-discard-granularity", VirtIOBlock, 1290 conf.report_discard_granularity, true), 1291 DEFINE_PROP_BIT64("write-zeroes", VirtIOBlock, host_features, 1292 VIRTIO_BLK_F_WRITE_ZEROES, true), 1293 DEFINE_PROP_UINT32("max-discard-sectors", VirtIOBlock, 1294 conf.max_discard_sectors, BDRV_REQUEST_MAX_SECTORS), 1295 DEFINE_PROP_UINT32("max-write-zeroes-sectors", VirtIOBlock, 1296 conf.max_write_zeroes_sectors, BDRV_REQUEST_MAX_SECTORS), 1297 DEFINE_PROP_BOOL("x-enable-wce-if-config-wce", VirtIOBlock, 1298 conf.x_enable_wce_if_config_wce, true), 1299 DEFINE_PROP_END_OF_LIST(), 1300 }; 1301 1302 static void virtio_blk_class_init(ObjectClass *klass, void *data) 1303 { 1304 DeviceClass *dc = DEVICE_CLASS(klass); 1305 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 1306 1307 device_class_set_props(dc, virtio_blk_properties); 1308 dc->vmsd = &vmstate_virtio_blk; 1309 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 1310 vdc->realize = virtio_blk_device_realize; 1311 vdc->unrealize = virtio_blk_device_unrealize; 1312 vdc->get_config = virtio_blk_update_config; 1313 vdc->set_config = virtio_blk_set_config; 1314 vdc->get_features = virtio_blk_get_features; 1315 vdc->set_status = virtio_blk_set_status; 1316 vdc->reset = virtio_blk_reset; 1317 vdc->save = virtio_blk_save_device; 1318 vdc->load = virtio_blk_load_device; 1319 vdc->start_ioeventfd = virtio_blk_data_plane_start; 1320 vdc->stop_ioeventfd = virtio_blk_data_plane_stop; 1321 } 1322 1323 static const TypeInfo virtio_blk_info = { 1324 .name = TYPE_VIRTIO_BLK, 1325 .parent = TYPE_VIRTIO_DEVICE, 1326 .instance_size = sizeof(VirtIOBlock), 1327 .instance_init = virtio_blk_instance_init, 1328 .class_init = virtio_blk_class_init, 1329 }; 1330 1331 static void virtio_register_types(void) 1332 { 1333 type_register_static(&virtio_blk_info); 1334 } 1335 1336 type_init(virtio_register_types) 1337