1 /* 2 * Virtio Block Device 3 * 4 * Copyright IBM, Corp. 2007 5 * 6 * Authors: 7 * Anthony Liguori <aliguori@us.ibm.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2. See 10 * the COPYING file in the top-level directory. 11 * 12 */ 13 14 #include "qemu/osdep.h" 15 #include "qapi/error.h" 16 #include "qemu/iov.h" 17 #include "qemu/module.h" 18 #include "qemu/error-report.h" 19 #include "qemu/main-loop.h" 20 #include "trace.h" 21 #include "hw/block/block.h" 22 #include "hw/qdev-properties.h" 23 #include "sysemu/blockdev.h" 24 #include "sysemu/sysemu.h" 25 #include "sysemu/runstate.h" 26 #include "hw/virtio/virtio-blk.h" 27 #include "dataplane/virtio-blk.h" 28 #include "scsi/constants.h" 29 #ifdef __linux__ 30 # include <scsi/sg.h> 31 #endif 32 #include "hw/virtio/virtio-bus.h" 33 #include "migration/qemu-file-types.h" 34 #include "hw/virtio/virtio-access.h" 35 36 /* Config size before the discard support (hide associated config fields) */ 37 #define VIRTIO_BLK_CFG_SIZE offsetof(struct virtio_blk_config, \ 38 max_discard_sectors) 39 /* 40 * Starting from the discard feature, we can use this array to properly 41 * set the config size depending on the features enabled. 42 */ 43 static VirtIOFeature feature_sizes[] = { 44 {.flags = 1ULL << VIRTIO_BLK_F_DISCARD, 45 .end = endof(struct virtio_blk_config, discard_sector_alignment)}, 46 {.flags = 1ULL << VIRTIO_BLK_F_WRITE_ZEROES, 47 .end = endof(struct virtio_blk_config, write_zeroes_may_unmap)}, 48 {} 49 }; 50 51 static void virtio_blk_set_config_size(VirtIOBlock *s, uint64_t host_features) 52 { 53 s->config_size = MAX(VIRTIO_BLK_CFG_SIZE, 54 virtio_feature_get_config_size(feature_sizes, host_features)); 55 56 assert(s->config_size <= sizeof(struct virtio_blk_config)); 57 } 58 59 static void virtio_blk_init_request(VirtIOBlock *s, VirtQueue *vq, 60 VirtIOBlockReq *req) 61 { 62 req->dev = s; 63 req->vq = vq; 64 req->qiov.size = 0; 65 req->in_len = 0; 66 req->next = NULL; 67 req->mr_next = NULL; 68 } 69 70 static void virtio_blk_free_request(VirtIOBlockReq *req) 71 { 72 g_free(req); 73 } 74 75 static void virtio_blk_req_complete(VirtIOBlockReq *req, unsigned char status) 76 { 77 VirtIOBlock *s = req->dev; 78 VirtIODevice *vdev = VIRTIO_DEVICE(s); 79 80 trace_virtio_blk_req_complete(vdev, req, status); 81 82 stb_p(&req->in->status, status); 83 virtqueue_push(req->vq, &req->elem, req->in_len); 84 if (s->dataplane_started && !s->dataplane_disabled) { 85 virtio_blk_data_plane_notify(s->dataplane, req->vq); 86 } else { 87 virtio_notify(vdev, req->vq); 88 } 89 } 90 91 static int virtio_blk_handle_rw_error(VirtIOBlockReq *req, int error, 92 bool is_read, bool acct_failed) 93 { 94 VirtIOBlock *s = req->dev; 95 BlockErrorAction action = blk_get_error_action(s->blk, is_read, error); 96 97 if (action == BLOCK_ERROR_ACTION_STOP) { 98 /* Break the link as the next request is going to be parsed from the 99 * ring again. Otherwise we may end up doing a double completion! */ 100 req->mr_next = NULL; 101 req->next = s->rq; 102 s->rq = req; 103 } else if (action == BLOCK_ERROR_ACTION_REPORT) { 104 virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR); 105 if (acct_failed) { 106 block_acct_failed(blk_get_stats(s->blk), &req->acct); 107 } 108 virtio_blk_free_request(req); 109 } 110 111 blk_error_action(s->blk, action, is_read, error); 112 return action != BLOCK_ERROR_ACTION_IGNORE; 113 } 114 115 static void virtio_blk_rw_complete(void *opaque, int ret) 116 { 117 VirtIOBlockReq *next = opaque; 118 VirtIOBlock *s = next->dev; 119 VirtIODevice *vdev = VIRTIO_DEVICE(s); 120 121 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 122 while (next) { 123 VirtIOBlockReq *req = next; 124 next = req->mr_next; 125 trace_virtio_blk_rw_complete(vdev, req, ret); 126 127 if (req->qiov.nalloc != -1) { 128 /* If nalloc is != -1 req->qiov is a local copy of the original 129 * external iovec. It was allocated in submit_requests to be 130 * able to merge requests. */ 131 qemu_iovec_destroy(&req->qiov); 132 } 133 134 if (ret) { 135 int p = virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type); 136 bool is_read = !(p & VIRTIO_BLK_T_OUT); 137 /* Note that memory may be dirtied on read failure. If the 138 * virtio request is not completed here, as is the case for 139 * BLOCK_ERROR_ACTION_STOP, the memory may not be copied 140 * correctly during live migration. While this is ugly, 141 * it is acceptable because the device is free to write to 142 * the memory until the request is completed (which will 143 * happen on the other side of the migration). 144 */ 145 if (virtio_blk_handle_rw_error(req, -ret, is_read, true)) { 146 continue; 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 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 155 } 156 157 static void virtio_blk_flush_complete(void *opaque, int ret) 158 { 159 VirtIOBlockReq *req = opaque; 160 VirtIOBlock *s = req->dev; 161 162 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 163 if (ret) { 164 if (virtio_blk_handle_rw_error(req, -ret, 0, true)) { 165 goto out; 166 } 167 } 168 169 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); 170 block_acct_done(blk_get_stats(s->blk), &req->acct); 171 virtio_blk_free_request(req); 172 173 out: 174 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 175 } 176 177 static void virtio_blk_discard_write_zeroes_complete(void *opaque, int ret) 178 { 179 VirtIOBlockReq *req = opaque; 180 VirtIOBlock *s = req->dev; 181 bool is_write_zeroes = (virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type) & 182 ~VIRTIO_BLK_T_BARRIER) == VIRTIO_BLK_T_WRITE_ZEROES; 183 184 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 185 if (ret) { 186 if (virtio_blk_handle_rw_error(req, -ret, false, is_write_zeroes)) { 187 goto out; 188 } 189 } 190 191 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); 192 if (is_write_zeroes) { 193 block_acct_done(blk_get_stats(s->blk), &req->acct); 194 } 195 virtio_blk_free_request(req); 196 197 out: 198 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 199 } 200 201 #ifdef __linux__ 202 203 typedef struct { 204 VirtIOBlockReq *req; 205 struct sg_io_hdr hdr; 206 } VirtIOBlockIoctlReq; 207 208 static void virtio_blk_ioctl_complete(void *opaque, int status) 209 { 210 VirtIOBlockIoctlReq *ioctl_req = opaque; 211 VirtIOBlockReq *req = ioctl_req->req; 212 VirtIOBlock *s = req->dev; 213 VirtIODevice *vdev = VIRTIO_DEVICE(s); 214 struct virtio_scsi_inhdr *scsi; 215 struct sg_io_hdr *hdr; 216 217 scsi = (void *)req->elem.in_sg[req->elem.in_num - 2].iov_base; 218 219 if (status) { 220 status = VIRTIO_BLK_S_UNSUPP; 221 virtio_stl_p(vdev, &scsi->errors, 255); 222 goto out; 223 } 224 225 hdr = &ioctl_req->hdr; 226 /* 227 * From SCSI-Generic-HOWTO: "Some lower level drivers (e.g. ide-scsi) 228 * clear the masked_status field [hence status gets cleared too, see 229 * block/scsi_ioctl.c] even when a CHECK_CONDITION or COMMAND_TERMINATED 230 * status has occurred. However they do set DRIVER_SENSE in driver_status 231 * field. Also a (sb_len_wr > 0) indicates there is a sense buffer. 232 */ 233 if (hdr->status == 0 && hdr->sb_len_wr > 0) { 234 hdr->status = CHECK_CONDITION; 235 } 236 237 virtio_stl_p(vdev, &scsi->errors, 238 hdr->status | (hdr->msg_status << 8) | 239 (hdr->host_status << 16) | (hdr->driver_status << 24)); 240 virtio_stl_p(vdev, &scsi->residual, hdr->resid); 241 virtio_stl_p(vdev, &scsi->sense_len, hdr->sb_len_wr); 242 virtio_stl_p(vdev, &scsi->data_len, hdr->dxfer_len); 243 244 out: 245 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 246 virtio_blk_req_complete(req, status); 247 virtio_blk_free_request(req); 248 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 249 g_free(ioctl_req); 250 } 251 252 #endif 253 254 static VirtIOBlockReq *virtio_blk_get_request(VirtIOBlock *s, VirtQueue *vq) 255 { 256 VirtIOBlockReq *req = virtqueue_pop(vq, sizeof(VirtIOBlockReq)); 257 258 if (req) { 259 virtio_blk_init_request(s, vq, req); 260 } 261 return req; 262 } 263 264 static int virtio_blk_handle_scsi_req(VirtIOBlockReq *req) 265 { 266 int status = VIRTIO_BLK_S_OK; 267 struct virtio_scsi_inhdr *scsi = NULL; 268 VirtIOBlock *blk = req->dev; 269 VirtIODevice *vdev = VIRTIO_DEVICE(blk); 270 VirtQueueElement *elem = &req->elem; 271 272 #ifdef __linux__ 273 int i; 274 VirtIOBlockIoctlReq *ioctl_req; 275 BlockAIOCB *acb; 276 #endif 277 278 /* 279 * We require at least one output segment each for the virtio_blk_outhdr 280 * and the SCSI command block. 281 * 282 * We also at least require the virtio_blk_inhdr, the virtio_scsi_inhdr 283 * and the sense buffer pointer in the input segments. 284 */ 285 if (elem->out_num < 2 || elem->in_num < 3) { 286 status = VIRTIO_BLK_S_IOERR; 287 goto fail; 288 } 289 290 /* 291 * The scsi inhdr is placed in the second-to-last input segment, just 292 * before the regular inhdr. 293 */ 294 scsi = (void *)elem->in_sg[elem->in_num - 2].iov_base; 295 296 if (!virtio_has_feature(blk->host_features, VIRTIO_BLK_F_SCSI)) { 297 status = VIRTIO_BLK_S_UNSUPP; 298 goto fail; 299 } 300 301 /* 302 * No support for bidirection commands yet. 303 */ 304 if (elem->out_num > 2 && elem->in_num > 3) { 305 status = VIRTIO_BLK_S_UNSUPP; 306 goto fail; 307 } 308 309 #ifdef __linux__ 310 ioctl_req = g_new0(VirtIOBlockIoctlReq, 1); 311 ioctl_req->req = req; 312 ioctl_req->hdr.interface_id = 'S'; 313 ioctl_req->hdr.cmd_len = elem->out_sg[1].iov_len; 314 ioctl_req->hdr.cmdp = elem->out_sg[1].iov_base; 315 ioctl_req->hdr.dxfer_len = 0; 316 317 if (elem->out_num > 2) { 318 /* 319 * If there are more than the minimally required 2 output segments 320 * there is write payload starting from the third iovec. 321 */ 322 ioctl_req->hdr.dxfer_direction = SG_DXFER_TO_DEV; 323 ioctl_req->hdr.iovec_count = elem->out_num - 2; 324 325 for (i = 0; i < ioctl_req->hdr.iovec_count; i++) { 326 ioctl_req->hdr.dxfer_len += elem->out_sg[i + 2].iov_len; 327 } 328 329 ioctl_req->hdr.dxferp = elem->out_sg + 2; 330 331 } else if (elem->in_num > 3) { 332 /* 333 * If we have more than 3 input segments the guest wants to actually 334 * read data. 335 */ 336 ioctl_req->hdr.dxfer_direction = SG_DXFER_FROM_DEV; 337 ioctl_req->hdr.iovec_count = elem->in_num - 3; 338 for (i = 0; i < ioctl_req->hdr.iovec_count; i++) { 339 ioctl_req->hdr.dxfer_len += elem->in_sg[i].iov_len; 340 } 341 342 ioctl_req->hdr.dxferp = elem->in_sg; 343 } else { 344 /* 345 * Some SCSI commands don't actually transfer any data. 346 */ 347 ioctl_req->hdr.dxfer_direction = SG_DXFER_NONE; 348 } 349 350 ioctl_req->hdr.sbp = elem->in_sg[elem->in_num - 3].iov_base; 351 ioctl_req->hdr.mx_sb_len = elem->in_sg[elem->in_num - 3].iov_len; 352 353 acb = blk_aio_ioctl(blk->blk, SG_IO, &ioctl_req->hdr, 354 virtio_blk_ioctl_complete, ioctl_req); 355 if (!acb) { 356 g_free(ioctl_req); 357 status = VIRTIO_BLK_S_UNSUPP; 358 goto fail; 359 } 360 return -EINPROGRESS; 361 #else 362 abort(); 363 #endif 364 365 fail: 366 /* Just put anything nonzero so that the ioctl fails in the guest. */ 367 if (scsi) { 368 virtio_stl_p(vdev, &scsi->errors, 255); 369 } 370 return status; 371 } 372 373 static void virtio_blk_handle_scsi(VirtIOBlockReq *req) 374 { 375 int status; 376 377 status = virtio_blk_handle_scsi_req(req); 378 if (status != -EINPROGRESS) { 379 virtio_blk_req_complete(req, status); 380 virtio_blk_free_request(req); 381 } 382 } 383 384 static inline void submit_requests(BlockBackend *blk, MultiReqBuffer *mrb, 385 int start, int num_reqs, int niov) 386 { 387 QEMUIOVector *qiov = &mrb->reqs[start]->qiov; 388 int64_t sector_num = mrb->reqs[start]->sector_num; 389 bool is_write = mrb->is_write; 390 391 if (num_reqs > 1) { 392 int i; 393 struct iovec *tmp_iov = qiov->iov; 394 int tmp_niov = qiov->niov; 395 396 /* mrb->reqs[start]->qiov was initialized from external so we can't 397 * modify it here. We need to initialize it locally and then add the 398 * external iovecs. */ 399 qemu_iovec_init(qiov, niov); 400 401 for (i = 0; i < tmp_niov; i++) { 402 qemu_iovec_add(qiov, tmp_iov[i].iov_base, tmp_iov[i].iov_len); 403 } 404 405 for (i = start + 1; i < start + num_reqs; i++) { 406 qemu_iovec_concat(qiov, &mrb->reqs[i]->qiov, 0, 407 mrb->reqs[i]->qiov.size); 408 mrb->reqs[i - 1]->mr_next = mrb->reqs[i]; 409 } 410 411 trace_virtio_blk_submit_multireq(VIRTIO_DEVICE(mrb->reqs[start]->dev), 412 mrb, start, num_reqs, 413 sector_num << BDRV_SECTOR_BITS, 414 qiov->size, is_write); 415 block_acct_merge_done(blk_get_stats(blk), 416 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ, 417 num_reqs - 1); 418 } 419 420 if (is_write) { 421 blk_aio_pwritev(blk, sector_num << BDRV_SECTOR_BITS, qiov, 0, 422 virtio_blk_rw_complete, mrb->reqs[start]); 423 } else { 424 blk_aio_preadv(blk, sector_num << BDRV_SECTOR_BITS, qiov, 0, 425 virtio_blk_rw_complete, mrb->reqs[start]); 426 } 427 } 428 429 static int multireq_compare(const void *a, const void *b) 430 { 431 const VirtIOBlockReq *req1 = *(VirtIOBlockReq **)a, 432 *req2 = *(VirtIOBlockReq **)b; 433 434 /* 435 * Note that we can't simply subtract sector_num1 from sector_num2 436 * here as that could overflow the return value. 437 */ 438 if (req1->sector_num > req2->sector_num) { 439 return 1; 440 } else if (req1->sector_num < req2->sector_num) { 441 return -1; 442 } else { 443 return 0; 444 } 445 } 446 447 static void virtio_blk_submit_multireq(BlockBackend *blk, MultiReqBuffer *mrb) 448 { 449 int i = 0, start = 0, num_reqs = 0, niov = 0, nb_sectors = 0; 450 uint32_t max_transfer; 451 int64_t sector_num = 0; 452 453 if (mrb->num_reqs == 1) { 454 submit_requests(blk, mrb, 0, 1, -1); 455 mrb->num_reqs = 0; 456 return; 457 } 458 459 max_transfer = blk_get_max_transfer(mrb->reqs[0]->dev->blk); 460 461 qsort(mrb->reqs, mrb->num_reqs, sizeof(*mrb->reqs), 462 &multireq_compare); 463 464 for (i = 0; i < mrb->num_reqs; i++) { 465 VirtIOBlockReq *req = mrb->reqs[i]; 466 if (num_reqs > 0) { 467 /* 468 * NOTE: We cannot merge the requests in below situations: 469 * 1. requests are not sequential 470 * 2. merge would exceed maximum number of IOVs 471 * 3. merge would exceed maximum transfer length of backend device 472 */ 473 if (sector_num + nb_sectors != req->sector_num || 474 niov > blk_get_max_iov(blk) - req->qiov.niov || 475 req->qiov.size > max_transfer || 476 nb_sectors > (max_transfer - 477 req->qiov.size) / BDRV_SECTOR_SIZE) { 478 submit_requests(blk, mrb, start, num_reqs, niov); 479 num_reqs = 0; 480 } 481 } 482 483 if (num_reqs == 0) { 484 sector_num = req->sector_num; 485 nb_sectors = niov = 0; 486 start = i; 487 } 488 489 nb_sectors += req->qiov.size / BDRV_SECTOR_SIZE; 490 niov += req->qiov.niov; 491 num_reqs++; 492 } 493 494 submit_requests(blk, mrb, start, num_reqs, niov); 495 mrb->num_reqs = 0; 496 } 497 498 static void virtio_blk_handle_flush(VirtIOBlockReq *req, MultiReqBuffer *mrb) 499 { 500 VirtIOBlock *s = req->dev; 501 502 block_acct_start(blk_get_stats(s->blk), &req->acct, 0, 503 BLOCK_ACCT_FLUSH); 504 505 /* 506 * Make sure all outstanding writes are posted to the backing device. 507 */ 508 if (mrb->is_write && mrb->num_reqs > 0) { 509 virtio_blk_submit_multireq(s->blk, mrb); 510 } 511 blk_aio_flush(s->blk, virtio_blk_flush_complete, req); 512 } 513 514 static bool virtio_blk_sect_range_ok(VirtIOBlock *dev, 515 uint64_t sector, size_t size) 516 { 517 uint64_t nb_sectors = size >> BDRV_SECTOR_BITS; 518 uint64_t total_sectors; 519 520 if (nb_sectors > BDRV_REQUEST_MAX_SECTORS) { 521 return false; 522 } 523 if (sector & dev->sector_mask) { 524 return false; 525 } 526 if (size % dev->conf.conf.logical_block_size) { 527 return false; 528 } 529 blk_get_geometry(dev->blk, &total_sectors); 530 if (sector > total_sectors || nb_sectors > total_sectors - sector) { 531 return false; 532 } 533 return true; 534 } 535 536 static uint8_t virtio_blk_handle_discard_write_zeroes(VirtIOBlockReq *req, 537 struct virtio_blk_discard_write_zeroes *dwz_hdr, bool is_write_zeroes) 538 { 539 VirtIOBlock *s = req->dev; 540 VirtIODevice *vdev = VIRTIO_DEVICE(s); 541 uint64_t sector; 542 uint32_t num_sectors, flags, max_sectors; 543 uint8_t err_status; 544 int bytes; 545 546 sector = virtio_ldq_p(vdev, &dwz_hdr->sector); 547 num_sectors = virtio_ldl_p(vdev, &dwz_hdr->num_sectors); 548 flags = virtio_ldl_p(vdev, &dwz_hdr->flags); 549 max_sectors = is_write_zeroes ? s->conf.max_write_zeroes_sectors : 550 s->conf.max_discard_sectors; 551 552 /* 553 * max_sectors is at most BDRV_REQUEST_MAX_SECTORS, this check 554 * make us sure that "num_sectors << BDRV_SECTOR_BITS" can fit in 555 * the integer variable. 556 */ 557 if (unlikely(num_sectors > max_sectors)) { 558 err_status = VIRTIO_BLK_S_IOERR; 559 goto err; 560 } 561 562 bytes = num_sectors << BDRV_SECTOR_BITS; 563 564 if (unlikely(!virtio_blk_sect_range_ok(s, sector, bytes))) { 565 err_status = VIRTIO_BLK_S_IOERR; 566 goto err; 567 } 568 569 /* 570 * The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for discard 571 * and write zeroes commands if any unknown flag is set. 572 */ 573 if (unlikely(flags & ~VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) { 574 err_status = VIRTIO_BLK_S_UNSUPP; 575 goto err; 576 } 577 578 if (is_write_zeroes) { /* VIRTIO_BLK_T_WRITE_ZEROES */ 579 int blk_aio_flags = 0; 580 581 if (flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP) { 582 blk_aio_flags |= BDRV_REQ_MAY_UNMAP; 583 } 584 585 block_acct_start(blk_get_stats(s->blk), &req->acct, bytes, 586 BLOCK_ACCT_WRITE); 587 588 blk_aio_pwrite_zeroes(s->blk, sector << BDRV_SECTOR_BITS, 589 bytes, blk_aio_flags, 590 virtio_blk_discard_write_zeroes_complete, req); 591 } else { /* VIRTIO_BLK_T_DISCARD */ 592 /* 593 * The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for 594 * discard commands if the unmap flag is set. 595 */ 596 if (unlikely(flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) { 597 err_status = VIRTIO_BLK_S_UNSUPP; 598 goto err; 599 } 600 601 blk_aio_pdiscard(s->blk, sector << BDRV_SECTOR_BITS, bytes, 602 virtio_blk_discard_write_zeroes_complete, req); 603 } 604 605 return VIRTIO_BLK_S_OK; 606 607 err: 608 if (is_write_zeroes) { 609 block_acct_invalid(blk_get_stats(s->blk), BLOCK_ACCT_WRITE); 610 } 611 return err_status; 612 } 613 614 static int virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb) 615 { 616 uint32_t type; 617 struct iovec *in_iov = req->elem.in_sg; 618 struct iovec *out_iov = req->elem.out_sg; 619 unsigned in_num = req->elem.in_num; 620 unsigned out_num = req->elem.out_num; 621 VirtIOBlock *s = req->dev; 622 VirtIODevice *vdev = VIRTIO_DEVICE(s); 623 624 if (req->elem.out_num < 1 || req->elem.in_num < 1) { 625 virtio_error(vdev, "virtio-blk missing headers"); 626 return -1; 627 } 628 629 if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out, 630 sizeof(req->out)) != sizeof(req->out))) { 631 virtio_error(vdev, "virtio-blk request outhdr too short"); 632 return -1; 633 } 634 635 iov_discard_front(&out_iov, &out_num, sizeof(req->out)); 636 637 if (in_iov[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) { 638 virtio_error(vdev, "virtio-blk request inhdr too short"); 639 return -1; 640 } 641 642 /* We always touch the last byte, so just see how big in_iov is. */ 643 req->in_len = iov_size(in_iov, in_num); 644 req->in = (void *)in_iov[in_num - 1].iov_base 645 + in_iov[in_num - 1].iov_len 646 - sizeof(struct virtio_blk_inhdr); 647 iov_discard_back(in_iov, &in_num, sizeof(struct virtio_blk_inhdr)); 648 649 type = virtio_ldl_p(vdev, &req->out.type); 650 651 /* VIRTIO_BLK_T_OUT defines the command direction. VIRTIO_BLK_T_BARRIER 652 * is an optional flag. Although a guest should not send this flag if 653 * not negotiated we ignored it in the past. So keep ignoring it. */ 654 switch (type & ~(VIRTIO_BLK_T_OUT | VIRTIO_BLK_T_BARRIER)) { 655 case VIRTIO_BLK_T_IN: 656 { 657 bool is_write = type & VIRTIO_BLK_T_OUT; 658 req->sector_num = virtio_ldq_p(vdev, &req->out.sector); 659 660 if (is_write) { 661 qemu_iovec_init_external(&req->qiov, out_iov, out_num); 662 trace_virtio_blk_handle_write(vdev, req, req->sector_num, 663 req->qiov.size / BDRV_SECTOR_SIZE); 664 } else { 665 qemu_iovec_init_external(&req->qiov, in_iov, in_num); 666 trace_virtio_blk_handle_read(vdev, req, req->sector_num, 667 req->qiov.size / BDRV_SECTOR_SIZE); 668 } 669 670 if (!virtio_blk_sect_range_ok(s, req->sector_num, req->qiov.size)) { 671 virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR); 672 block_acct_invalid(blk_get_stats(s->blk), 673 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ); 674 virtio_blk_free_request(req); 675 return 0; 676 } 677 678 block_acct_start(blk_get_stats(s->blk), &req->acct, req->qiov.size, 679 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ); 680 681 /* merge would exceed maximum number of requests or IO direction 682 * changes */ 683 if (mrb->num_reqs > 0 && (mrb->num_reqs == VIRTIO_BLK_MAX_MERGE_REQS || 684 is_write != mrb->is_write || 685 !s->conf.request_merging)) { 686 virtio_blk_submit_multireq(s->blk, mrb); 687 } 688 689 assert(mrb->num_reqs < VIRTIO_BLK_MAX_MERGE_REQS); 690 mrb->reqs[mrb->num_reqs++] = req; 691 mrb->is_write = is_write; 692 break; 693 } 694 case VIRTIO_BLK_T_FLUSH: 695 virtio_blk_handle_flush(req, mrb); 696 break; 697 case VIRTIO_BLK_T_SCSI_CMD: 698 virtio_blk_handle_scsi(req); 699 break; 700 case VIRTIO_BLK_T_GET_ID: 701 { 702 /* 703 * NB: per existing s/n string convention the string is 704 * terminated by '\0' only when shorter than buffer. 705 */ 706 const char *serial = s->conf.serial ? s->conf.serial : ""; 707 size_t size = MIN(strlen(serial) + 1, 708 MIN(iov_size(in_iov, in_num), 709 VIRTIO_BLK_ID_BYTES)); 710 iov_from_buf(in_iov, in_num, 0, serial, size); 711 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK); 712 virtio_blk_free_request(req); 713 break; 714 } 715 /* 716 * VIRTIO_BLK_T_DISCARD and VIRTIO_BLK_T_WRITE_ZEROES are defined with 717 * VIRTIO_BLK_T_OUT flag set. We masked this flag in the switch statement, 718 * so we must mask it for these requests, then we will check if it is set. 719 */ 720 case VIRTIO_BLK_T_DISCARD & ~VIRTIO_BLK_T_OUT: 721 case VIRTIO_BLK_T_WRITE_ZEROES & ~VIRTIO_BLK_T_OUT: 722 { 723 struct virtio_blk_discard_write_zeroes dwz_hdr; 724 size_t out_len = iov_size(out_iov, out_num); 725 bool is_write_zeroes = (type & ~VIRTIO_BLK_T_BARRIER) == 726 VIRTIO_BLK_T_WRITE_ZEROES; 727 uint8_t err_status; 728 729 /* 730 * Unsupported if VIRTIO_BLK_T_OUT is not set or the request contains 731 * more than one segment. 732 */ 733 if (unlikely(!(type & VIRTIO_BLK_T_OUT) || 734 out_len > sizeof(dwz_hdr))) { 735 virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP); 736 virtio_blk_free_request(req); 737 return 0; 738 } 739 740 if (unlikely(iov_to_buf(out_iov, out_num, 0, &dwz_hdr, 741 sizeof(dwz_hdr)) != sizeof(dwz_hdr))) { 742 virtio_error(vdev, "virtio-blk discard/write_zeroes header" 743 " too short"); 744 return -1; 745 } 746 747 err_status = virtio_blk_handle_discard_write_zeroes(req, &dwz_hdr, 748 is_write_zeroes); 749 if (err_status != VIRTIO_BLK_S_OK) { 750 virtio_blk_req_complete(req, err_status); 751 virtio_blk_free_request(req); 752 } 753 754 break; 755 } 756 default: 757 virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP); 758 virtio_blk_free_request(req); 759 } 760 return 0; 761 } 762 763 bool virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq) 764 { 765 VirtIOBlockReq *req; 766 MultiReqBuffer mrb = {}; 767 bool suppress_notifications = virtio_queue_get_notification(vq); 768 bool progress = false; 769 770 aio_context_acquire(blk_get_aio_context(s->blk)); 771 blk_io_plug(s->blk); 772 773 do { 774 if (suppress_notifications) { 775 virtio_queue_set_notification(vq, 0); 776 } 777 778 while ((req = virtio_blk_get_request(s, vq))) { 779 progress = true; 780 if (virtio_blk_handle_request(req, &mrb)) { 781 virtqueue_detach_element(req->vq, &req->elem, 0); 782 virtio_blk_free_request(req); 783 break; 784 } 785 } 786 787 if (suppress_notifications) { 788 virtio_queue_set_notification(vq, 1); 789 } 790 } while (!virtio_queue_empty(vq)); 791 792 if (mrb.num_reqs) { 793 virtio_blk_submit_multireq(s->blk, &mrb); 794 } 795 796 blk_io_unplug(s->blk); 797 aio_context_release(blk_get_aio_context(s->blk)); 798 return progress; 799 } 800 801 static void virtio_blk_handle_output_do(VirtIOBlock *s, VirtQueue *vq) 802 { 803 virtio_blk_handle_vq(s, vq); 804 } 805 806 static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq) 807 { 808 VirtIOBlock *s = (VirtIOBlock *)vdev; 809 810 if (s->dataplane) { 811 /* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start 812 * dataplane here instead of waiting for .set_status(). 813 */ 814 virtio_device_start_ioeventfd(vdev); 815 if (!s->dataplane_disabled) { 816 return; 817 } 818 } 819 virtio_blk_handle_output_do(s, vq); 820 } 821 822 void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh) 823 { 824 VirtIOBlockReq *req = s->rq; 825 MultiReqBuffer mrb = {}; 826 827 s->rq = NULL; 828 829 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk)); 830 while (req) { 831 VirtIOBlockReq *next = req->next; 832 if (virtio_blk_handle_request(req, &mrb)) { 833 /* Device is now broken and won't do any processing until it gets 834 * reset. Already queued requests will be lost: let's purge them. 835 */ 836 while (req) { 837 next = req->next; 838 virtqueue_detach_element(req->vq, &req->elem, 0); 839 virtio_blk_free_request(req); 840 req = next; 841 } 842 break; 843 } 844 req = next; 845 } 846 847 if (mrb.num_reqs) { 848 virtio_blk_submit_multireq(s->blk, &mrb); 849 } 850 if (is_bh) { 851 blk_dec_in_flight(s->conf.conf.blk); 852 } 853 aio_context_release(blk_get_aio_context(s->conf.conf.blk)); 854 } 855 856 static void virtio_blk_dma_restart_bh(void *opaque) 857 { 858 VirtIOBlock *s = opaque; 859 860 qemu_bh_delete(s->bh); 861 s->bh = NULL; 862 863 virtio_blk_process_queued_requests(s, true); 864 } 865 866 static void virtio_blk_dma_restart_cb(void *opaque, int running, 867 RunState state) 868 { 869 VirtIOBlock *s = opaque; 870 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s))); 871 VirtioBusState *bus = VIRTIO_BUS(qbus); 872 873 if (!running) { 874 return; 875 } 876 877 /* 878 * If ioeventfd is enabled, don't schedule the BH here as queued 879 * requests will be processed while starting the data plane. 880 */ 881 if (!s->bh && !virtio_bus_ioeventfd_enabled(bus)) { 882 s->bh = aio_bh_new(blk_get_aio_context(s->conf.conf.blk), 883 virtio_blk_dma_restart_bh, s); 884 blk_inc_in_flight(s->conf.conf.blk); 885 qemu_bh_schedule(s->bh); 886 } 887 } 888 889 static void virtio_blk_reset(VirtIODevice *vdev) 890 { 891 VirtIOBlock *s = VIRTIO_BLK(vdev); 892 AioContext *ctx; 893 VirtIOBlockReq *req; 894 895 ctx = blk_get_aio_context(s->blk); 896 aio_context_acquire(ctx); 897 blk_drain(s->blk); 898 899 /* We drop queued requests after blk_drain() because blk_drain() itself can 900 * produce them. */ 901 while (s->rq) { 902 req = s->rq; 903 s->rq = req->next; 904 virtqueue_detach_element(req->vq, &req->elem, 0); 905 virtio_blk_free_request(req); 906 } 907 908 aio_context_release(ctx); 909 910 assert(!s->dataplane_started); 911 blk_set_enable_write_cache(s->blk, s->original_wce); 912 } 913 914 /* coalesce internal state, copy to pci i/o region 0 915 */ 916 static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config) 917 { 918 VirtIOBlock *s = VIRTIO_BLK(vdev); 919 BlockConf *conf = &s->conf.conf; 920 struct virtio_blk_config blkcfg; 921 uint64_t capacity; 922 int64_t length; 923 int blk_size = conf->logical_block_size; 924 925 blk_get_geometry(s->blk, &capacity); 926 memset(&blkcfg, 0, sizeof(blkcfg)); 927 virtio_stq_p(vdev, &blkcfg.capacity, capacity); 928 virtio_stl_p(vdev, &blkcfg.seg_max, 929 s->conf.seg_max_adjust ? s->conf.queue_size - 2 : 128 - 2); 930 virtio_stw_p(vdev, &blkcfg.geometry.cylinders, conf->cyls); 931 virtio_stl_p(vdev, &blkcfg.blk_size, blk_size); 932 virtio_stw_p(vdev, &blkcfg.min_io_size, conf->min_io_size / blk_size); 933 virtio_stl_p(vdev, &blkcfg.opt_io_size, conf->opt_io_size / blk_size); 934 blkcfg.geometry.heads = conf->heads; 935 /* 936 * We must ensure that the block device capacity is a multiple of 937 * the logical block size. If that is not the case, let's use 938 * sector_mask to adopt the geometry to have a correct picture. 939 * For those devices where the capacity is ok for the given geometry 940 * we don't touch the sector value of the geometry, since some devices 941 * (like s390 dasd) need a specific value. Here the capacity is already 942 * cyls*heads*secs*blk_size and the sector value is not block size 943 * divided by 512 - instead it is the amount of blk_size blocks 944 * per track (cylinder). 945 */ 946 length = blk_getlength(s->blk); 947 if (length > 0 && length / conf->heads / conf->secs % blk_size) { 948 blkcfg.geometry.sectors = conf->secs & ~s->sector_mask; 949 } else { 950 blkcfg.geometry.sectors = conf->secs; 951 } 952 blkcfg.size_max = 0; 953 blkcfg.physical_block_exp = get_physical_block_exp(conf); 954 blkcfg.alignment_offset = 0; 955 blkcfg.wce = blk_enable_write_cache(s->blk); 956 virtio_stw_p(vdev, &blkcfg.num_queues, s->conf.num_queues); 957 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD)) { 958 virtio_stl_p(vdev, &blkcfg.max_discard_sectors, 959 s->conf.max_discard_sectors); 960 virtio_stl_p(vdev, &blkcfg.discard_sector_alignment, 961 blk_size >> BDRV_SECTOR_BITS); 962 /* 963 * We support only one segment per request since multiple segments 964 * are not widely used and there are no userspace APIs that allow 965 * applications to submit multiple segments in a single call. 966 */ 967 virtio_stl_p(vdev, &blkcfg.max_discard_seg, 1); 968 } 969 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES)) { 970 virtio_stl_p(vdev, &blkcfg.max_write_zeroes_sectors, 971 s->conf.max_write_zeroes_sectors); 972 blkcfg.write_zeroes_may_unmap = 1; 973 virtio_stl_p(vdev, &blkcfg.max_write_zeroes_seg, 1); 974 } 975 memcpy(config, &blkcfg, s->config_size); 976 } 977 978 static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config) 979 { 980 VirtIOBlock *s = VIRTIO_BLK(vdev); 981 struct virtio_blk_config blkcfg; 982 983 memcpy(&blkcfg, config, s->config_size); 984 985 aio_context_acquire(blk_get_aio_context(s->blk)); 986 blk_set_enable_write_cache(s->blk, blkcfg.wce != 0); 987 aio_context_release(blk_get_aio_context(s->blk)); 988 } 989 990 static uint64_t virtio_blk_get_features(VirtIODevice *vdev, uint64_t features, 991 Error **errp) 992 { 993 VirtIOBlock *s = VIRTIO_BLK(vdev); 994 995 /* Firstly sync all virtio-blk possible supported features */ 996 features |= s->host_features; 997 998 virtio_add_feature(&features, VIRTIO_BLK_F_SEG_MAX); 999 virtio_add_feature(&features, VIRTIO_BLK_F_GEOMETRY); 1000 virtio_add_feature(&features, VIRTIO_BLK_F_TOPOLOGY); 1001 virtio_add_feature(&features, VIRTIO_BLK_F_BLK_SIZE); 1002 if (virtio_has_feature(features, VIRTIO_F_VERSION_1)) { 1003 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_SCSI)) { 1004 error_setg(errp, "Please set scsi=off for virtio-blk devices in order to use virtio 1.0"); 1005 return 0; 1006 } 1007 } else { 1008 virtio_clear_feature(&features, VIRTIO_F_ANY_LAYOUT); 1009 virtio_add_feature(&features, VIRTIO_BLK_F_SCSI); 1010 } 1011 1012 if (blk_enable_write_cache(s->blk) || 1013 (s->conf.x_enable_wce_if_config_wce && 1014 virtio_has_feature(features, VIRTIO_BLK_F_CONFIG_WCE))) { 1015 virtio_add_feature(&features, VIRTIO_BLK_F_WCE); 1016 } 1017 if (blk_is_read_only(s->blk)) { 1018 virtio_add_feature(&features, VIRTIO_BLK_F_RO); 1019 } 1020 if (s->conf.num_queues > 1) { 1021 virtio_add_feature(&features, VIRTIO_BLK_F_MQ); 1022 } 1023 1024 return features; 1025 } 1026 1027 static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status) 1028 { 1029 VirtIOBlock *s = VIRTIO_BLK(vdev); 1030 1031 if (!(status & (VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK))) { 1032 assert(!s->dataplane_started); 1033 } 1034 1035 if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) { 1036 return; 1037 } 1038 1039 /* A guest that supports VIRTIO_BLK_F_CONFIG_WCE must be able to send 1040 * cache flushes. Thus, the "auto writethrough" behavior is never 1041 * necessary for guests that support the VIRTIO_BLK_F_CONFIG_WCE feature. 1042 * Leaving it enabled would break the following sequence: 1043 * 1044 * Guest started with "-drive cache=writethrough" 1045 * Guest sets status to 0 1046 * Guest sets DRIVER bit in status field 1047 * Guest reads host features (WCE=0, CONFIG_WCE=1) 1048 * Guest writes guest features (WCE=0, CONFIG_WCE=1) 1049 * Guest writes 1 to the WCE configuration field (writeback mode) 1050 * Guest sets DRIVER_OK bit in status field 1051 * 1052 * s->blk would erroneously be placed in writethrough mode. 1053 */ 1054 if (!virtio_vdev_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE)) { 1055 aio_context_acquire(blk_get_aio_context(s->blk)); 1056 blk_set_enable_write_cache(s->blk, 1057 virtio_vdev_has_feature(vdev, 1058 VIRTIO_BLK_F_WCE)); 1059 aio_context_release(blk_get_aio_context(s->blk)); 1060 } 1061 } 1062 1063 static void virtio_blk_save_device(VirtIODevice *vdev, QEMUFile *f) 1064 { 1065 VirtIOBlock *s = VIRTIO_BLK(vdev); 1066 VirtIOBlockReq *req = s->rq; 1067 1068 while (req) { 1069 qemu_put_sbyte(f, 1); 1070 1071 if (s->conf.num_queues > 1) { 1072 qemu_put_be32(f, virtio_get_queue_index(req->vq)); 1073 } 1074 1075 qemu_put_virtqueue_element(vdev, f, &req->elem); 1076 req = req->next; 1077 } 1078 qemu_put_sbyte(f, 0); 1079 } 1080 1081 static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f, 1082 int version_id) 1083 { 1084 VirtIOBlock *s = VIRTIO_BLK(vdev); 1085 1086 while (qemu_get_sbyte(f)) { 1087 unsigned nvqs = s->conf.num_queues; 1088 unsigned vq_idx = 0; 1089 VirtIOBlockReq *req; 1090 1091 if (nvqs > 1) { 1092 vq_idx = qemu_get_be32(f); 1093 1094 if (vq_idx >= nvqs) { 1095 error_report("Invalid virtqueue index in request list: %#x", 1096 vq_idx); 1097 return -EINVAL; 1098 } 1099 } 1100 1101 req = qemu_get_virtqueue_element(vdev, f, sizeof(VirtIOBlockReq)); 1102 virtio_blk_init_request(s, virtio_get_queue(vdev, vq_idx), req); 1103 req->next = s->rq; 1104 s->rq = req; 1105 } 1106 1107 return 0; 1108 } 1109 1110 static void virtio_resize_cb(void *opaque) 1111 { 1112 VirtIODevice *vdev = opaque; 1113 1114 assert(qemu_get_current_aio_context() == qemu_get_aio_context()); 1115 virtio_notify_config(vdev); 1116 } 1117 1118 static void virtio_blk_resize(void *opaque) 1119 { 1120 VirtIODevice *vdev = VIRTIO_DEVICE(opaque); 1121 1122 /* 1123 * virtio_notify_config() needs to acquire the global mutex, 1124 * so it can't be called from an iothread. Instead, schedule 1125 * it to be run in the main context BH. 1126 */ 1127 aio_bh_schedule_oneshot(qemu_get_aio_context(), virtio_resize_cb, vdev); 1128 } 1129 1130 static const BlockDevOps virtio_block_ops = { 1131 .resize_cb = virtio_blk_resize, 1132 }; 1133 1134 static void virtio_blk_device_realize(DeviceState *dev, Error **errp) 1135 { 1136 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 1137 VirtIOBlock *s = VIRTIO_BLK(dev); 1138 VirtIOBlkConf *conf = &s->conf; 1139 Error *err = NULL; 1140 unsigned i; 1141 1142 if (!conf->conf.blk) { 1143 error_setg(errp, "drive property not set"); 1144 return; 1145 } 1146 if (!blk_is_inserted(conf->conf.blk)) { 1147 error_setg(errp, "Device needs media, but drive is empty"); 1148 return; 1149 } 1150 if (conf->num_queues == VIRTIO_BLK_AUTO_NUM_QUEUES) { 1151 conf->num_queues = 1; 1152 } 1153 if (!conf->num_queues) { 1154 error_setg(errp, "num-queues property must be larger than 0"); 1155 return; 1156 } 1157 if (conf->queue_size <= 2) { 1158 error_setg(errp, "invalid queue-size property (%" PRIu16 "), " 1159 "must be > 2", conf->queue_size); 1160 return; 1161 } 1162 if (!is_power_of_2(conf->queue_size) || 1163 conf->queue_size > VIRTQUEUE_MAX_SIZE) { 1164 error_setg(errp, "invalid queue-size property (%" PRIu16 "), " 1165 "must be a power of 2 (max %d)", 1166 conf->queue_size, VIRTQUEUE_MAX_SIZE); 1167 return; 1168 } 1169 1170 if (!blkconf_apply_backend_options(&conf->conf, 1171 blk_is_read_only(conf->conf.blk), true, 1172 errp)) { 1173 return; 1174 } 1175 s->original_wce = blk_enable_write_cache(conf->conf.blk); 1176 if (!blkconf_geometry(&conf->conf, NULL, 65535, 255, 255, errp)) { 1177 return; 1178 } 1179 1180 if (!blkconf_blocksizes(&conf->conf, errp)) { 1181 return; 1182 } 1183 1184 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD) && 1185 (!conf->max_discard_sectors || 1186 conf->max_discard_sectors > BDRV_REQUEST_MAX_SECTORS)) { 1187 error_setg(errp, "invalid max-discard-sectors property (%" PRIu32 ")" 1188 ", must be between 1 and %d", 1189 conf->max_discard_sectors, (int)BDRV_REQUEST_MAX_SECTORS); 1190 return; 1191 } 1192 1193 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES) && 1194 (!conf->max_write_zeroes_sectors || 1195 conf->max_write_zeroes_sectors > BDRV_REQUEST_MAX_SECTORS)) { 1196 error_setg(errp, "invalid max-write-zeroes-sectors property (%" PRIu32 1197 "), must be between 1 and %d", 1198 conf->max_write_zeroes_sectors, 1199 (int)BDRV_REQUEST_MAX_SECTORS); 1200 return; 1201 } 1202 1203 virtio_blk_set_config_size(s, s->host_features); 1204 1205 virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, s->config_size); 1206 1207 s->blk = conf->conf.blk; 1208 s->rq = NULL; 1209 s->sector_mask = (s->conf.conf.logical_block_size / BDRV_SECTOR_SIZE) - 1; 1210 1211 for (i = 0; i < conf->num_queues; i++) { 1212 virtio_add_queue(vdev, conf->queue_size, virtio_blk_handle_output); 1213 } 1214 virtio_blk_data_plane_create(vdev, conf, &s->dataplane, &err); 1215 if (err != NULL) { 1216 error_propagate(errp, err); 1217 for (i = 0; i < conf->num_queues; i++) { 1218 virtio_del_queue(vdev, i); 1219 } 1220 virtio_cleanup(vdev); 1221 return; 1222 } 1223 1224 s->change = qemu_add_vm_change_state_handler(virtio_blk_dma_restart_cb, s); 1225 blk_set_dev_ops(s->blk, &virtio_block_ops, s); 1226 blk_set_guest_block_size(s->blk, s->conf.conf.logical_block_size); 1227 1228 blk_iostatus_enable(s->blk); 1229 1230 add_boot_device_lchs(dev, "/disk@0,0", 1231 conf->conf.lcyls, 1232 conf->conf.lheads, 1233 conf->conf.lsecs); 1234 } 1235 1236 static void virtio_blk_device_unrealize(DeviceState *dev) 1237 { 1238 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 1239 VirtIOBlock *s = VIRTIO_BLK(dev); 1240 VirtIOBlkConf *conf = &s->conf; 1241 unsigned i; 1242 1243 blk_drain(s->blk); 1244 del_boot_device_lchs(dev, "/disk@0,0"); 1245 virtio_blk_data_plane_destroy(s->dataplane); 1246 s->dataplane = NULL; 1247 for (i = 0; i < conf->num_queues; i++) { 1248 virtio_del_queue(vdev, i); 1249 } 1250 qemu_del_vm_change_state_handler(s->change); 1251 blockdev_mark_auto_del(s->blk); 1252 virtio_cleanup(vdev); 1253 } 1254 1255 static void virtio_blk_instance_init(Object *obj) 1256 { 1257 VirtIOBlock *s = VIRTIO_BLK(obj); 1258 1259 device_add_bootindex_property(obj, &s->conf.conf.bootindex, 1260 "bootindex", "/disk@0,0", 1261 DEVICE(obj)); 1262 } 1263 1264 static const VMStateDescription vmstate_virtio_blk = { 1265 .name = "virtio-blk", 1266 .minimum_version_id = 2, 1267 .version_id = 2, 1268 .fields = (VMStateField[]) { 1269 VMSTATE_VIRTIO_DEVICE, 1270 VMSTATE_END_OF_LIST() 1271 }, 1272 }; 1273 1274 static Property virtio_blk_properties[] = { 1275 DEFINE_BLOCK_PROPERTIES(VirtIOBlock, conf.conf), 1276 DEFINE_BLOCK_ERROR_PROPERTIES(VirtIOBlock, conf.conf), 1277 DEFINE_BLOCK_CHS_PROPERTIES(VirtIOBlock, conf.conf), 1278 DEFINE_PROP_STRING("serial", VirtIOBlock, conf.serial), 1279 DEFINE_PROP_BIT64("config-wce", VirtIOBlock, host_features, 1280 VIRTIO_BLK_F_CONFIG_WCE, true), 1281 #ifdef __linux__ 1282 DEFINE_PROP_BIT64("scsi", VirtIOBlock, host_features, 1283 VIRTIO_BLK_F_SCSI, false), 1284 #endif 1285 DEFINE_PROP_BIT("request-merging", VirtIOBlock, conf.request_merging, 0, 1286 true), 1287 DEFINE_PROP_UINT16("num-queues", VirtIOBlock, conf.num_queues, 1288 VIRTIO_BLK_AUTO_NUM_QUEUES), 1289 DEFINE_PROP_UINT16("queue-size", VirtIOBlock, conf.queue_size, 256), 1290 DEFINE_PROP_BOOL("seg-max-adjust", VirtIOBlock, conf.seg_max_adjust, true), 1291 DEFINE_PROP_LINK("iothread", VirtIOBlock, conf.iothread, TYPE_IOTHREAD, 1292 IOThread *), 1293 DEFINE_PROP_BIT64("discard", VirtIOBlock, host_features, 1294 VIRTIO_BLK_F_DISCARD, true), 1295 DEFINE_PROP_BIT64("write-zeroes", VirtIOBlock, host_features, 1296 VIRTIO_BLK_F_WRITE_ZEROES, true), 1297 DEFINE_PROP_UINT32("max-discard-sectors", VirtIOBlock, 1298 conf.max_discard_sectors, BDRV_REQUEST_MAX_SECTORS), 1299 DEFINE_PROP_UINT32("max-write-zeroes-sectors", VirtIOBlock, 1300 conf.max_write_zeroes_sectors, BDRV_REQUEST_MAX_SECTORS), 1301 DEFINE_PROP_BOOL("x-enable-wce-if-config-wce", VirtIOBlock, 1302 conf.x_enable_wce_if_config_wce, true), 1303 DEFINE_PROP_END_OF_LIST(), 1304 }; 1305 1306 static void virtio_blk_class_init(ObjectClass *klass, void *data) 1307 { 1308 DeviceClass *dc = DEVICE_CLASS(klass); 1309 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 1310 1311 device_class_set_props(dc, virtio_blk_properties); 1312 dc->vmsd = &vmstate_virtio_blk; 1313 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 1314 vdc->realize = virtio_blk_device_realize; 1315 vdc->unrealize = virtio_blk_device_unrealize; 1316 vdc->get_config = virtio_blk_update_config; 1317 vdc->set_config = virtio_blk_set_config; 1318 vdc->get_features = virtio_blk_get_features; 1319 vdc->set_status = virtio_blk_set_status; 1320 vdc->reset = virtio_blk_reset; 1321 vdc->save = virtio_blk_save_device; 1322 vdc->load = virtio_blk_load_device; 1323 vdc->start_ioeventfd = virtio_blk_data_plane_start; 1324 vdc->stop_ioeventfd = virtio_blk_data_plane_stop; 1325 } 1326 1327 static const TypeInfo virtio_blk_info = { 1328 .name = TYPE_VIRTIO_BLK, 1329 .parent = TYPE_VIRTIO_DEVICE, 1330 .instance_size = sizeof(VirtIOBlock), 1331 .instance_init = virtio_blk_instance_init, 1332 .class_init = virtio_blk_class_init, 1333 }; 1334 1335 static void virtio_register_types(void) 1336 { 1337 type_register_static(&virtio_blk_info); 1338 } 1339 1340 type_init(virtio_register_types) 1341