hw/scsi/virtio-scsi.c

   1 /*
   2  * Virtio SCSI HBA
   3  *
   4  * Copyright IBM, Corp. 2010
   5  * Copyright Red Hat, Inc. 2011
   6  *
   7  * Authors:
   8  *   Stefan Hajnoczi    <stefanha@linux.vnet.ibm.com>
   9  *   Paolo Bonzini      <pbonzini@redhat.com>
  10  *
  11  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  12  * See the COPYING file in the top-level directory.
  13  *
  14  */
  15
  16 #include "qemu/osdep.h"
  17 #include "qapi/error.h"
  18 #include "standard-headers/linux/virtio_ids.h"
  19 #include "hw/virtio/virtio-scsi.h"
  20 #include "migration/qemu-file-types.h"
  21 #include "qemu/error-report.h"
  22 #include "qemu/iov.h"
  23 #include "qemu/module.h"
  24 #include "sysemu/block-backend.h"
  25 #include "hw/qdev-properties.h"
  26 #include "hw/scsi/scsi.h"
  27 #include "scsi/constants.h"
  28 #include "hw/virtio/virtio-bus.h"
  29 #include "hw/virtio/virtio-access.h"
  30 #include "trace.h"
  31
  32 typedef struct VirtIOSCSIReq {
  33     /*
  34      * Note:
  35      * - fields up to resp_iov are initialized by virtio_scsi_init_req;
  36      * - fields starting at vring are zeroed by virtio_scsi_init_req.
  37      */
  38     VirtQueueElement elem;
  39
  40     VirtIOSCSI *dev;
  41     VirtQueue *vq;
  42     QEMUSGList qsgl;
  43     QEMUIOVector resp_iov;
  44
  45     union {
  46         /* Used for two-stage request submission */
  47         QTAILQ_ENTRY(VirtIOSCSIReq) next;
  48
  49         /* Used for cancellation of request during TMFs */
  50         int remaining;
  51     };
  52
  53     SCSIRequest *sreq;
  54     size_t resp_size;
  55     enum SCSIXferMode mode;
  56     union {
  57         VirtIOSCSICmdResp     cmd;
  58         VirtIOSCSICtrlTMFResp tmf;
  59         VirtIOSCSICtrlANResp  an;
  60         VirtIOSCSIEvent       event;
  61     } resp;
  62     union {
  63         VirtIOSCSICmdReq      cmd;
  64         VirtIOSCSICtrlTMFReq  tmf;
  65         VirtIOSCSICtrlANReq   an;
  66     } req;
  67 } VirtIOSCSIReq;
  68
  69 static inline int virtio_scsi_get_lun(uint8_t *lun)
  70 {
  71     return ((lun[2] << 8) | lun[3]) & 0x3FFF;
  72 }
  73
  74 static inline SCSIDevice *virtio_scsi_device_get(VirtIOSCSI *s, uint8_t *lun)
  75 {
  76     if (lun[0] != 1) {
  77         return NULL;
  78     }
  79     if (lun[2] != 0 && !(lun[2] >= 0x40 && lun[2] < 0x80)) {
  80         return NULL;
  81     }
  82     return scsi_device_get(&s->bus, 0, lun[1], virtio_scsi_get_lun(lun));
  83 }
  84
  85 static void virtio_scsi_init_req(VirtIOSCSI *s, VirtQueue *vq, VirtIOSCSIReq *req)
  86 {
  87     VirtIODevice *vdev = VIRTIO_DEVICE(s);
  88     const size_t zero_skip =
  89         offsetof(VirtIOSCSIReq, resp_iov) + sizeof(req->resp_iov);
  90
  91     req->vq = vq;
  92     req->dev = s;
  93     qemu_sglist_init(&req->qsgl, DEVICE(s), 8, vdev->dma_as);
  94     qemu_iovec_init(&req->resp_iov, 1);
  95     memset((uint8_t *)req + zero_skip, 0, sizeof(*req) - zero_skip);
  96 }
  97
  98 static void virtio_scsi_free_req(VirtIOSCSIReq *req)
  99 {
 100     qemu_iovec_destroy(&req->resp_iov);
 101     qemu_sglist_destroy(&req->qsgl);
 102     g_free(req);
 103 }
 104
 105 static void virtio_scsi_complete_req(VirtIOSCSIReq *req)
 106 {
 107     VirtIOSCSI *s = req->dev;
 108     VirtQueue *vq = req->vq;
 109     VirtIODevice *vdev = VIRTIO_DEVICE(s);
 110
 111     qemu_iovec_from_buf(&req->resp_iov, 0, &req->resp, req->resp_size);
 112     virtqueue_push(vq, &req->elem, req->qsgl.size + req->resp_iov.size);
 113     if (s->dataplane_started && !s->dataplane_fenced) {
 114         virtio_notify_irqfd(vdev, vq);
 115     } else {
 116         virtio_notify(vdev, vq);
 117     }
 118
 119     if (req->sreq) {
 120         req->sreq->hba_private = NULL;
 121         scsi_req_unref(req->sreq);
 122     }
 123     virtio_scsi_free_req(req);
 124 }
 125
 126 static void virtio_scsi_bad_req(VirtIOSCSIReq *req)
 127 {
 128     virtio_error(VIRTIO_DEVICE(req->dev), "wrong size for virtio-scsi headers");
 129     virtqueue_detach_element(req->vq, &req->elem, 0);
 130     virtio_scsi_free_req(req);
 131 }
 132
 133 static size_t qemu_sgl_concat(VirtIOSCSIReq *req, struct iovec *iov,
 134                               hwaddr *addr, int num, size_t skip)
 135 {
 136     QEMUSGList *qsgl = &req->qsgl;
 137     size_t copied = 0;
 138
 139     while (num) {
 140         if (skip >= iov->iov_len) {
 141             skip -= iov->iov_len;
 142         } else {
 143             qemu_sglist_add(qsgl, *addr + skip, iov->iov_len - skip);
 144             copied += iov->iov_len - skip;
 145             skip = 0;
 146         }
 147         iov++;
 148         addr++;
 149         num--;
 150     }
 151
 152     assert(skip == 0);
 153     return copied;
 154 }
 155
 156 static int virtio_scsi_parse_req(VirtIOSCSIReq *req,
 157                                  unsigned req_size, unsigned resp_size)
 158 {
 159     VirtIODevice *vdev = (VirtIODevice *) req->dev;
 160     size_t in_size, out_size;
 161
 162     if (iov_to_buf(req->elem.out_sg, req->elem.out_num, 0,
 163                    &req->req, req_size) < req_size) {
 164         return -EINVAL;
 165     }
 166
 167     if (qemu_iovec_concat_iov(&req->resp_iov,
 168                               req->elem.in_sg, req->elem.in_num, 0,
 169                               resp_size) < resp_size) {
 170         return -EINVAL;
 171     }
 172
 173     req->resp_size = resp_size;
 174
 175     /* Old BIOSes left some padding by mistake after the req_size/resp_size.
 176      * As a workaround, always consider the first buffer as the virtio-scsi
 177      * request/response, making the payload start at the second element
 178      * of the iovec.
 179      *
 180      * The actual length of the response header, stored in req->resp_size,
 181      * does not change.
 182      *
 183      * TODO: always disable this workaround for virtio 1.0 devices.
 184      */
 185     if (!virtio_vdev_has_feature(vdev, VIRTIO_F_ANY_LAYOUT)) {
 186         if (req->elem.out_num) {
 187             req_size = req->elem.out_sg[0].iov_len;
 188         }
 189         if (req->elem.in_num) {
 190             resp_size = req->elem.in_sg[0].iov_len;
 191         }
 192     }
 193
 194     out_size = qemu_sgl_concat(req, req->elem.out_sg,
 195                                &req->elem.out_addr[0], req->elem.out_num,
 196                                req_size);
 197     in_size = qemu_sgl_concat(req, req->elem.in_sg,
 198                               &req->elem.in_addr[0], req->elem.in_num,
 199                               resp_size);
 200
 201     if (out_size && in_size) {
 202         return -ENOTSUP;
 203     }
 204
 205     if (out_size) {
 206         req->mode = SCSI_XFER_TO_DEV;
 207     } else if (in_size) {
 208         req->mode = SCSI_XFER_FROM_DEV;
 209     }
 210
 211     return 0;
 212 }
 213
 214 static VirtIOSCSIReq *virtio_scsi_pop_req(VirtIOSCSI *s, VirtQueue *vq)
 215 {
 216     VirtIOSCSICommon *vs = (VirtIOSCSICommon *)s;
 217     VirtIOSCSIReq *req;
 218
 219     req = virtqueue_pop(vq, sizeof(VirtIOSCSIReq) + vs->cdb_size);
 220     if (!req) {
 221         return NULL;
 222     }
 223     virtio_scsi_init_req(s, vq, req);
 224     return req;
 225 }
 226
 227 static void virtio_scsi_save_request(QEMUFile *f, SCSIRequest *sreq)
 228 {
 229     VirtIOSCSIReq *req = sreq->hba_private;
 230     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(req->dev);
 231     VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
 232     uint32_t n = virtio_get_queue_index(req->vq) - VIRTIO_SCSI_VQ_NUM_FIXED;
 233
 234     assert(n < vs->conf.num_queues);
 235     qemu_put_be32s(f, &n);
 236     qemu_put_virtqueue_element(vdev, f, &req->elem);
 237 }
 238
 239 static void *virtio_scsi_load_request(QEMUFile *f, SCSIRequest *sreq)
 240 {
 241     SCSIBus *bus = sreq->bus;
 242     VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus);
 243     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
 244     VirtIODevice *vdev = VIRTIO_DEVICE(s);
 245     VirtIOSCSIReq *req;
 246     uint32_t n;
 247
 248     qemu_get_be32s(f, &n);
 249     assert(n < vs->conf.num_queues);
 250     req = qemu_get_virtqueue_element(vdev, f,
 251                                      sizeof(VirtIOSCSIReq) + vs->cdb_size);
 252     virtio_scsi_init_req(s, vs->cmd_vqs[n], req);
 253
 254     if (virtio_scsi_parse_req(req, sizeof(VirtIOSCSICmdReq) + vs->cdb_size,
 255                               sizeof(VirtIOSCSICmdResp) + vs->sense_size) < 0) {
 256         error_report("invalid SCSI request migration data");
 257         exit(1);
 258     }
 259
 260     scsi_req_ref(sreq);
 261     req->sreq = sreq;
 262     if (req->sreq->cmd.mode != SCSI_XFER_NONE) {
 263         assert(req->sreq->cmd.mode == req->mode);
 264     }
 265     return req;
 266 }
 267
 268 typedef struct {
 269     Notifier        notifier;
 270     VirtIOSCSIReq  *tmf_req;
 271 } VirtIOSCSICancelNotifier;
 272
 273 static void virtio_scsi_cancel_notify(Notifier *notifier, void *data)
 274 {
 275     VirtIOSCSICancelNotifier *n = container_of(notifier,
 276                                                VirtIOSCSICancelNotifier,
 277                                                notifier);
 278
 279     if (--n->tmf_req->remaining == 0) {
 280         VirtIOSCSIReq *req = n->tmf_req;
 281
 282         trace_virtio_scsi_tmf_resp(virtio_scsi_get_lun(req->req.tmf.lun),
 283                                    req->req.tmf.tag, req->resp.tmf.response);
 284         virtio_scsi_complete_req(req);
 285     }
 286     g_free(n);
 287 }
 288
 289 static inline void virtio_scsi_ctx_check(VirtIOSCSI *s, SCSIDevice *d)
 290 {
 291     if (s->dataplane_started && d && blk_is_available(d->conf.blk)) {
 292         assert(blk_get_aio_context(d->conf.blk) == s->ctx);
 293     }
 294 }
 295
 296 /* Return 0 if the request is ready to be completed and return to guest;
 297  * -EINPROGRESS if the request is submitted and will be completed later, in the
 298  *  case of async cancellation. */
 299 static int virtio_scsi_do_tmf(VirtIOSCSI *s, VirtIOSCSIReq *req)
 300 {
 301     SCSIDevice *d = virtio_scsi_device_get(s, req->req.tmf.lun);
 302     SCSIRequest *r, *next;
 303     BusChild *kid;
 304     int target;
 305     int ret = 0;
 306
 307     virtio_scsi_ctx_check(s, d);
 308     /* Here VIRTIO_SCSI_S_OK means "FUNCTION COMPLETE".  */
 309     req->resp.tmf.response = VIRTIO_SCSI_S_OK;
 310
 311     /*
 312      * req->req.tmf has the QEMU_PACKED attribute. Don't use virtio_tswap32s()
 313      * to avoid compiler errors.
 314      */
 315     req->req.tmf.subtype =
 316         virtio_tswap32(VIRTIO_DEVICE(s), req->req.tmf.subtype);
 317
 318     trace_virtio_scsi_tmf_req(virtio_scsi_get_lun(req->req.tmf.lun),
 319                               req->req.tmf.tag, req->req.tmf.subtype);
 320
 321     switch (req->req.tmf.subtype) {
 322     case VIRTIO_SCSI_T_TMF_ABORT_TASK:
 323     case VIRTIO_SCSI_T_TMF_QUERY_TASK:
 324         if (!d) {
 325             goto fail;
 326         }
 327         if (d->lun != virtio_scsi_get_lun(req->req.tmf.lun)) {
 328             goto incorrect_lun;
 329         }
 330         QTAILQ_FOREACH_SAFE(r, &d->requests, next, next) {
 331             VirtIOSCSIReq *cmd_req = r->hba_private;
 332             if (cmd_req && cmd_req->req.cmd.tag == req->req.tmf.tag) {
 333                 break;
 334             }
 335         }
 336         if (r) {
 337             /*
 338              * Assert that the request has not been completed yet, we
 339              * check for it in the loop above.
 340              */
 341             assert(r->hba_private);
 342             if (req->req.tmf.subtype == VIRTIO_SCSI_T_TMF_QUERY_TASK) {
 343                 /* "If the specified command is present in the task set, then
 344                  * return a service response set to FUNCTION SUCCEEDED".
 345                  */
 346                 req->resp.tmf.response = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
 347             } else {
 348                 VirtIOSCSICancelNotifier *notifier;
 349
 350                 req->remaining = 1;
 351                 notifier = g_new(VirtIOSCSICancelNotifier, 1);
 352                 notifier->tmf_req = req;
 353                 notifier->notifier.notify = virtio_scsi_cancel_notify;
 354                 scsi_req_cancel_async(r, &notifier->notifier);
 355                 ret = -EINPROGRESS;
 356             }
 357         }
 358         break;
 359
 360     case VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET:
 361         if (!d) {
 362             goto fail;
 363         }
 364         if (d->lun != virtio_scsi_get_lun(req->req.tmf.lun)) {
 365             goto incorrect_lun;
 366         }
 367         s->resetting++;
 368         qdev_reset_all(&d->qdev);
 369         s->resetting--;
 370         break;
 371
 372     case VIRTIO_SCSI_T_TMF_ABORT_TASK_SET:
 373     case VIRTIO_SCSI_T_TMF_CLEAR_TASK_SET:
 374     case VIRTIO_SCSI_T_TMF_QUERY_TASK_SET:
 375         if (!d) {
 376             goto fail;
 377         }
 378         if (d->lun != virtio_scsi_get_lun(req->req.tmf.lun)) {
 379             goto incorrect_lun;
 380         }
 381
 382         /* Add 1 to "remaining" until virtio_scsi_do_tmf returns.
 383          * This way, if the bus starts calling back to the notifiers
 384          * even before we finish the loop, virtio_scsi_cancel_notify
 385          * will not complete the TMF too early.
 386          */
 387         req->remaining = 1;
 388         QTAILQ_FOREACH_SAFE(r, &d->requests, next, next) {
 389             if (r->hba_private) {
 390                 if (req->req.tmf.subtype == VIRTIO_SCSI_T_TMF_QUERY_TASK_SET) {
 391                     /* "If there is any command present in the task set, then
 392                      * return a service response set to FUNCTION SUCCEEDED".
 393                      */
 394                     req->resp.tmf.response = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
 395                     break;
 396                 } else {
 397                     VirtIOSCSICancelNotifier *notifier;
 398
 399                     req->remaining++;
 400                     notifier = g_new(VirtIOSCSICancelNotifier, 1);
 401                     notifier->notifier.notify = virtio_scsi_cancel_notify;
 402                     notifier->tmf_req = req;
 403                     scsi_req_cancel_async(r, &notifier->notifier);
 404                 }
 405             }
 406         }
 407         if (--req->remaining > 0) {
 408             ret = -EINPROGRESS;
 409         }
 410         break;
 411
 412     case VIRTIO_SCSI_T_TMF_I_T_NEXUS_RESET:
 413         target = req->req.tmf.lun[1];
 414         s->resetting++;
 415
 416         rcu_read_lock();
 417         QTAILQ_FOREACH_RCU(kid, &s->bus.qbus.children, sibling) {
 418             SCSIDevice *d1 = SCSI_DEVICE(kid->child);
 419             if (d1->channel == 0 && d1->id == target) {
 420                 qdev_reset_all(&d1->qdev);
 421             }
 422         }
 423         rcu_read_unlock();
 424
 425         s->resetting--;
 426         break;
 427
 428     case VIRTIO_SCSI_T_TMF_CLEAR_ACA:
 429     default:
 430         req->resp.tmf.response = VIRTIO_SCSI_S_FUNCTION_REJECTED;
 431         break;
 432     }
 433
 434     object_unref(OBJECT(d));
 435     return ret;
 436
 437 incorrect_lun:
 438     req->resp.tmf.response = VIRTIO_SCSI_S_INCORRECT_LUN;
 439     object_unref(OBJECT(d));
 440     return ret;
 441
 442 fail:
 443     req->resp.tmf.response = VIRTIO_SCSI_S_BAD_TARGET;
 444     object_unref(OBJECT(d));
 445     return ret;
 446 }
 447
 448 static void virtio_scsi_handle_ctrl_req(VirtIOSCSI *s, VirtIOSCSIReq *req)
 449 {
 450     VirtIODevice *vdev = (VirtIODevice *)s;
 451     uint32_t type;
 452     int r = 0;
 453
 454     if (iov_to_buf(req->elem.out_sg, req->elem.out_num, 0,
 455                 &type, sizeof(type)) < sizeof(type)) {
 456         virtio_scsi_bad_req(req);
 457         return;
 458     }
 459
 460     virtio_tswap32s(vdev, &type);
 461     if (type == VIRTIO_SCSI_T_TMF) {
 462         if (virtio_scsi_parse_req(req, sizeof(VirtIOSCSICtrlTMFReq),
 463                     sizeof(VirtIOSCSICtrlTMFResp)) < 0) {
 464             virtio_scsi_bad_req(req);
 465             return;
 466         } else {
 467             r = virtio_scsi_do_tmf(s, req);
 468         }
 469
 470     } else if (type == VIRTIO_SCSI_T_AN_QUERY ||
 471                type == VIRTIO_SCSI_T_AN_SUBSCRIBE) {
 472         if (virtio_scsi_parse_req(req, sizeof(VirtIOSCSICtrlANReq),
 473                     sizeof(VirtIOSCSICtrlANResp)) < 0) {
 474             virtio_scsi_bad_req(req);
 475             return;
 476         } else {
 477             req->req.an.event_requested =
 478                 virtio_tswap32(VIRTIO_DEVICE(s), req->req.an.event_requested);
 479             trace_virtio_scsi_an_req(virtio_scsi_get_lun(req->req.an.lun),
 480                                      req->req.an.event_requested);
 481             req->resp.an.event_actual = 0;
 482             req->resp.an.response = VIRTIO_SCSI_S_OK;
 483         }
 484     }
 485     if (r == 0) {
 486         if (type == VIRTIO_SCSI_T_TMF)
 487             trace_virtio_scsi_tmf_resp(virtio_scsi_get_lun(req->req.tmf.lun),
 488                                        req->req.tmf.tag,
 489                                        req->resp.tmf.response);
 490         else if (type == VIRTIO_SCSI_T_AN_QUERY ||
 491                  type == VIRTIO_SCSI_T_AN_SUBSCRIBE)
 492             trace_virtio_scsi_an_resp(virtio_scsi_get_lun(req->req.an.lun),
 493                                       req->resp.an.response);
 494         virtio_scsi_complete_req(req);
 495     } else {
 496         assert(r == -EINPROGRESS);
 497     }
 498 }
 499
 500 static void virtio_scsi_handle_ctrl_vq(VirtIOSCSI *s, VirtQueue *vq)
 501 {
 502     VirtIOSCSIReq *req;
 503
 504     while ((req = virtio_scsi_pop_req(s, vq))) {
 505         virtio_scsi_handle_ctrl_req(s, req);
 506     }
 507 }
 508
 509 /*
 510  * If dataplane is configured but not yet started, do so now and return true on
 511  * success.
 512  *
 513  * Dataplane is started by the core virtio code but virtqueue handler functions
 514  * can also be invoked when a guest kicks before DRIVER_OK, so this helper
 515  * function helps us deal with manually starting ioeventfd in that case.
 516  */
 517 static bool virtio_scsi_defer_to_dataplane(VirtIOSCSI *s)
 518 {
 519     if (!s->ctx || s->dataplane_started) {
 520         return false;
 521     }
 522
 523     virtio_device_start_ioeventfd(&s->parent_obj.parent_obj);
 524     return !s->dataplane_fenced;
 525 }
 526
 527 static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
 528 {
 529     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 530
 531     if (virtio_scsi_defer_to_dataplane(s)) {
 532         return;
 533     }
 534
 535     virtio_scsi_acquire(s);
 536     virtio_scsi_handle_ctrl_vq(s, vq);
 537     virtio_scsi_release(s);
 538 }
 539
 540 static void virtio_scsi_complete_cmd_req(VirtIOSCSIReq *req)
 541 {
 542     trace_virtio_scsi_cmd_resp(virtio_scsi_get_lun(req->req.cmd.lun),
 543                                req->req.cmd.tag,
 544                                req->resp.cmd.response,
 545                                req->resp.cmd.status);
 546     /* Sense data is not in req->resp and is copied separately
 547      * in virtio_scsi_command_complete.
 548      */
 549     req->resp_size = sizeof(VirtIOSCSICmdResp);
 550     virtio_scsi_complete_req(req);
 551 }
 552
 553 static void virtio_scsi_command_failed(SCSIRequest *r)
 554 {
 555     VirtIOSCSIReq *req = r->hba_private;
 556
 557     if (r->io_canceled) {
 558         return;
 559     }
 560
 561     req->resp.cmd.status = GOOD;
 562     switch (r->host_status) {
 563     case SCSI_HOST_NO_LUN:
 564         req->resp.cmd.response = VIRTIO_SCSI_S_INCORRECT_LUN;
 565         break;
 566     case SCSI_HOST_BUSY:
 567         req->resp.cmd.response = VIRTIO_SCSI_S_BUSY;
 568         break;
 569     case SCSI_HOST_TIME_OUT:
 570     case SCSI_HOST_ABORTED:
 571         req->resp.cmd.response = VIRTIO_SCSI_S_ABORTED;
 572         break;
 573     case SCSI_HOST_BAD_RESPONSE:
 574         req->resp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET;
 575         break;
 576     case SCSI_HOST_RESET:
 577         req->resp.cmd.response = VIRTIO_SCSI_S_RESET;
 578         break;
 579     case SCSI_HOST_TRANSPORT_DISRUPTED:
 580         req->resp.cmd.response = VIRTIO_SCSI_S_TRANSPORT_FAILURE;
 581         break;
 582     case SCSI_HOST_TARGET_FAILURE:
 583         req->resp.cmd.response = VIRTIO_SCSI_S_TARGET_FAILURE;
 584         break;
 585     case SCSI_HOST_RESERVATION_ERROR:
 586         req->resp.cmd.response = VIRTIO_SCSI_S_NEXUS_FAILURE;
 587         break;
 588     case SCSI_HOST_ALLOCATION_FAILURE:
 589     case SCSI_HOST_MEDIUM_ERROR:
 590     case SCSI_HOST_ERROR:
 591     default:
 592         req->resp.cmd.response = VIRTIO_SCSI_S_FAILURE;
 593         break;
 594     }
 595     virtio_scsi_complete_cmd_req(req);
 596 }
 597
 598 static void virtio_scsi_command_complete(SCSIRequest *r, size_t resid)
 599 {
 600     VirtIOSCSIReq *req = r->hba_private;
 601     uint8_t sense[SCSI_SENSE_BUF_SIZE];
 602     uint32_t sense_len;
 603     VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
 604
 605     if (r->io_canceled) {
 606         return;
 607     }
 608
 609     req->resp.cmd.response = VIRTIO_SCSI_S_OK;
 610     req->resp.cmd.status = r->status;
 611     if (req->resp.cmd.status == GOOD) {
 612         req->resp.cmd.resid = virtio_tswap32(vdev, resid);
 613     } else {
 614         req->resp.cmd.resid = 0;
 615         sense_len = scsi_req_get_sense(r, sense, sizeof(sense));
 616         sense_len = MIN(sense_len, req->resp_iov.size - sizeof(req->resp.cmd));
 617         qemu_iovec_from_buf(&req->resp_iov, sizeof(req->resp.cmd),
 618                             sense, sense_len);
 619         req->resp.cmd.sense_len = virtio_tswap32(vdev, sense_len);
 620     }
 621     virtio_scsi_complete_cmd_req(req);
 622 }
 623
 624 static int virtio_scsi_parse_cdb(SCSIDevice *dev, SCSICommand *cmd,
 625                                  uint8_t *buf, void *hba_private)
 626 {
 627     VirtIOSCSIReq *req = hba_private;
 628
 629     if (cmd->len == 0) {
 630         cmd->len = MIN(VIRTIO_SCSI_CDB_DEFAULT_SIZE, SCSI_CMD_BUF_SIZE);
 631         memcpy(cmd->buf, buf, cmd->len);
 632     }
 633
 634     /* Extract the direction and mode directly from the request, for
 635      * host device passthrough.
 636      */
 637     cmd->xfer = req->qsgl.size;
 638     cmd->mode = req->mode;
 639     return 0;
 640 }
 641
 642 static QEMUSGList *virtio_scsi_get_sg_list(SCSIRequest *r)
 643 {
 644     VirtIOSCSIReq *req = r->hba_private;
 645
 646     return &req->qsgl;
 647 }
 648
 649 static void virtio_scsi_request_cancelled(SCSIRequest *r)
 650 {
 651     VirtIOSCSIReq *req = r->hba_private;
 652
 653     if (!req) {
 654         return;
 655     }
 656     if (req->dev->resetting) {
 657         req->resp.cmd.response = VIRTIO_SCSI_S_RESET;
 658     } else {
 659         req->resp.cmd.response = VIRTIO_SCSI_S_ABORTED;
 660     }
 661     virtio_scsi_complete_cmd_req(req);
 662 }
 663
 664 static void virtio_scsi_fail_cmd_req(VirtIOSCSIReq *req)
 665 {
 666     req->resp.cmd.response = VIRTIO_SCSI_S_FAILURE;
 667     virtio_scsi_complete_cmd_req(req);
 668 }
 669
 670 static int virtio_scsi_handle_cmd_req_prepare(VirtIOSCSI *s, VirtIOSCSIReq *req)
 671 {
 672     VirtIOSCSICommon *vs = &s->parent_obj;
 673     SCSIDevice *d;
 674     int rc;
 675
 676     rc = virtio_scsi_parse_req(req, sizeof(VirtIOSCSICmdReq) + vs->cdb_size,
 677                                sizeof(VirtIOSCSICmdResp) + vs->sense_size);
 678     if (rc < 0) {
 679         if (rc == -ENOTSUP) {
 680             virtio_scsi_fail_cmd_req(req);
 681             return -ENOTSUP;
 682         } else {
 683             virtio_scsi_bad_req(req);
 684             return -EINVAL;
 685         }
 686     }
 687     trace_virtio_scsi_cmd_req(virtio_scsi_get_lun(req->req.cmd.lun),
 688                               req->req.cmd.tag, req->req.cmd.cdb[0]);
 689
 690     d = virtio_scsi_device_get(s, req->req.cmd.lun);
 691     if (!d) {
 692         req->resp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET;
 693         virtio_scsi_complete_cmd_req(req);
 694         return -ENOENT;
 695     }
 696     virtio_scsi_ctx_check(s, d);
 697     req->sreq = scsi_req_new(d, req->req.cmd.tag,
 698                              virtio_scsi_get_lun(req->req.cmd.lun),
 699                              req->req.cmd.cdb, req);
 700
 701     if (req->sreq->cmd.mode != SCSI_XFER_NONE
 702         && (req->sreq->cmd.mode != req->mode ||
 703             req->sreq->cmd.xfer > req->qsgl.size)) {
 704         req->resp.cmd.response = VIRTIO_SCSI_S_OVERRUN;
 705         virtio_scsi_complete_cmd_req(req);
 706         object_unref(OBJECT(d));
 707         return -ENOBUFS;
 708     }
 709     scsi_req_ref(req->sreq);
 710     blk_io_plug(d->conf.blk);
 711     object_unref(OBJECT(d));
 712     return 0;
 713 }
 714
 715 static void virtio_scsi_handle_cmd_req_submit(VirtIOSCSI *s, VirtIOSCSIReq *req)
 716 {
 717     SCSIRequest *sreq = req->sreq;
 718     if (scsi_req_enqueue(sreq)) {
 719         scsi_req_continue(sreq);
 720     }
 721     blk_io_unplug(sreq->dev->conf.blk);
 722     scsi_req_unref(sreq);
 723 }
 724
 725 static void virtio_scsi_handle_cmd_vq(VirtIOSCSI *s, VirtQueue *vq)
 726 {
 727     VirtIOSCSIReq *req, *next;
 728     int ret = 0;
 729     bool suppress_notifications = virtio_queue_get_notification(vq);
 730
 731     QTAILQ_HEAD(, VirtIOSCSIReq) reqs = QTAILQ_HEAD_INITIALIZER(reqs);
 732
 733     do {
 734         if (suppress_notifications) {
 735             virtio_queue_set_notification(vq, 0);
 736         }
 737
 738         while ((req = virtio_scsi_pop_req(s, vq))) {
 739             ret = virtio_scsi_handle_cmd_req_prepare(s, req);
 740             if (!ret) {
 741                 QTAILQ_INSERT_TAIL(&reqs, req, next);
 742             } else if (ret == -EINVAL) {
 743                 /* The device is broken and shouldn't process any request */
 744                 while (!QTAILQ_EMPTY(&reqs)) {
 745                     req = QTAILQ_FIRST(&reqs);
 746                     QTAILQ_REMOVE(&reqs, req, next);
 747                     blk_io_unplug(req->sreq->dev->conf.blk);
 748                     scsi_req_unref(req->sreq);
 749                     virtqueue_detach_element(req->vq, &req->elem, 0);
 750                     virtio_scsi_free_req(req);
 751                 }
 752             }
 753         }
 754
 755         if (suppress_notifications) {
 756             virtio_queue_set_notification(vq, 1);
 757         }
 758     } while (ret != -EINVAL && !virtio_queue_empty(vq));
 759
 760     QTAILQ_FOREACH_SAFE(req, &reqs, next, next) {
 761         virtio_scsi_handle_cmd_req_submit(s, req);
 762     }
 763 }
 764
 765 static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
 766 {
 767     /* use non-QOM casts in the data path */
 768     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 769
 770     if (virtio_scsi_defer_to_dataplane(s)) {
 771         return;
 772     }
 773
 774     virtio_scsi_acquire(s);
 775     virtio_scsi_handle_cmd_vq(s, vq);
 776     virtio_scsi_release(s);
 777 }
 778
 779 static void virtio_scsi_get_config(VirtIODevice *vdev,
 780                                    uint8_t *config)
 781 {
 782     VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config;
 783     VirtIOSCSICommon *s = VIRTIO_SCSI_COMMON(vdev);
 784
 785     virtio_stl_p(vdev, &scsiconf->num_queues, s->conf.num_queues);
 786     virtio_stl_p(vdev, &scsiconf->seg_max,
 787                  s->conf.seg_max_adjust ? s->conf.virtqueue_size - 2 : 128 - 2);
 788     virtio_stl_p(vdev, &scsiconf->max_sectors, s->conf.max_sectors);
 789     virtio_stl_p(vdev, &scsiconf->cmd_per_lun, s->conf.cmd_per_lun);
 790     virtio_stl_p(vdev, &scsiconf->event_info_size, sizeof(VirtIOSCSIEvent));
 791     virtio_stl_p(vdev, &scsiconf->sense_size, s->sense_size);
 792     virtio_stl_p(vdev, &scsiconf->cdb_size, s->cdb_size);
 793     virtio_stw_p(vdev, &scsiconf->max_channel, VIRTIO_SCSI_MAX_CHANNEL);
 794     virtio_stw_p(vdev, &scsiconf->max_target, VIRTIO_SCSI_MAX_TARGET);
 795     virtio_stl_p(vdev, &scsiconf->max_lun, VIRTIO_SCSI_MAX_LUN);
 796 }
 797
 798 static void virtio_scsi_set_config(VirtIODevice *vdev,
 799                                    const uint8_t *config)
 800 {
 801     VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config;
 802     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev);
 803
 804     if ((uint32_t) virtio_ldl_p(vdev, &scsiconf->sense_size) >= 65536 ||
 805         (uint32_t) virtio_ldl_p(vdev, &scsiconf->cdb_size) >= 256) {
 806         virtio_error(vdev,
 807                      "bad data written to virtio-scsi configuration space");
 808         return;
 809     }
 810
 811     vs->sense_size = virtio_ldl_p(vdev, &scsiconf->sense_size);
 812     vs->cdb_size = virtio_ldl_p(vdev, &scsiconf->cdb_size);
 813 }
 814
 815 static uint64_t virtio_scsi_get_features(VirtIODevice *vdev,
 816                                          uint64_t requested_features,
 817                                          Error **errp)
 818 {
 819     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 820
 821     /* Firstly sync all virtio-scsi possible supported features */
 822     requested_features |= s->host_features;
 823     return requested_features;
 824 }
 825
 826 static void virtio_scsi_reset(VirtIODevice *vdev)
 827 {
 828     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 829     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev);
 830
 831     assert(!s->dataplane_started);
 832     s->resetting++;
 833     qbus_reset_all(BUS(&s->bus));
 834     s->resetting--;
 835
 836     vs->sense_size = VIRTIO_SCSI_SENSE_DEFAULT_SIZE;
 837     vs->cdb_size = VIRTIO_SCSI_CDB_DEFAULT_SIZE;
 838     s->events_dropped = false;
 839 }
 840
 841 static void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev,
 842                                    uint32_t event, uint32_t reason)
 843 {
 844     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
 845     VirtIOSCSIReq *req;
 846     VirtIOSCSIEvent *evt;
 847     VirtIODevice *vdev = VIRTIO_DEVICE(s);
 848
 849     if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
 850         return;
 851     }
 852
 853     req = virtio_scsi_pop_req(s, vs->event_vq);
 854     if (!req) {
 855         s->events_dropped = true;
 856         return;
 857     }
 858
 859     if (s->events_dropped) {
 860         event |= VIRTIO_SCSI_T_EVENTS_MISSED;
 861         s->events_dropped = false;
 862     }
 863
 864     if (virtio_scsi_parse_req(req, 0, sizeof(VirtIOSCSIEvent))) {
 865         virtio_scsi_bad_req(req);
 866         return;
 867     }
 868
 869     evt = &req->resp.event;
 870     memset(evt, 0, sizeof(VirtIOSCSIEvent));
 871     evt->event = virtio_tswap32(vdev, event);
 872     evt->reason = virtio_tswap32(vdev, reason);
 873     if (!dev) {
 874         assert(event == VIRTIO_SCSI_T_EVENTS_MISSED);
 875     } else {
 876         evt->lun[0] = 1;
 877         evt->lun[1] = dev->id;
 878
 879         /* Linux wants us to keep the same encoding we use for REPORT LUNS.  */
 880         if (dev->lun >= 256) {
 881             evt->lun[2] = (dev->lun >> 8) | 0x40;
 882         }
 883         evt->lun[3] = dev->lun & 0xFF;
 884     }
 885     trace_virtio_scsi_event(virtio_scsi_get_lun(evt->lun), event, reason);
 886
 887     virtio_scsi_complete_req(req);
 888 }
 889
 890 static void virtio_scsi_handle_event_vq(VirtIOSCSI *s, VirtQueue *vq)
 891 {
 892     if (s->events_dropped) {
 893         virtio_scsi_push_event(s, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
 894     }
 895 }
 896
 897 static void virtio_scsi_handle_event(VirtIODevice *vdev, VirtQueue *vq)
 898 {
 899     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 900
 901     if (virtio_scsi_defer_to_dataplane(s)) {
 902         return;
 903     }
 904
 905     virtio_scsi_acquire(s);
 906     virtio_scsi_handle_event_vq(s, vq);
 907     virtio_scsi_release(s);
 908 }
 909
 910 static void virtio_scsi_change(SCSIBus *bus, SCSIDevice *dev, SCSISense sense)
 911 {
 912     VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus);
 913     VirtIODevice *vdev = VIRTIO_DEVICE(s);
 914
 915     if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_CHANGE) &&
 916         dev->type != TYPE_ROM) {
 917         virtio_scsi_acquire(s);
 918         virtio_scsi_push_event(s, dev, VIRTIO_SCSI_T_PARAM_CHANGE,
 919                                sense.asc | (sense.ascq << 8));
 920         virtio_scsi_release(s);
 921     }
 922 }
 923
 924 static void virtio_scsi_pre_hotplug(HotplugHandler *hotplug_dev,
 925                                     DeviceState *dev, Error **errp)
 926 {
 927     SCSIDevice *sd = SCSI_DEVICE(dev);
 928     sd->hba_supports_iothread = true;
 929 }
 930
 931 static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState *dev,
 932                                 Error **errp)
 933 {
 934     VirtIODevice *vdev = VIRTIO_DEVICE(hotplug_dev);
 935     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 936     SCSIDevice *sd = SCSI_DEVICE(dev);
 937     AioContext *old_context;
 938     int ret;
 939
 940     if (s->ctx && !s->dataplane_fenced) {
 941         if (blk_op_is_blocked(sd->conf.blk, BLOCK_OP_TYPE_DATAPLANE, errp)) {
 942             return;
 943         }
 944         old_context = blk_get_aio_context(sd->conf.blk);
 945         aio_context_acquire(old_context);
 946         ret = blk_set_aio_context(sd->conf.blk, s->ctx, errp);
 947         aio_context_release(old_context);
 948         if (ret < 0) {
 949             return;
 950         }
 951     }
 952
 953     if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) {
 954         virtio_scsi_acquire(s);
 955         virtio_scsi_push_event(s, sd,
 956                                VIRTIO_SCSI_T_TRANSPORT_RESET,
 957                                VIRTIO_SCSI_EVT_RESET_RESCAN);
 958         virtio_scsi_release(s);
 959     }
 960 }
 961
 962 static void virtio_scsi_hotunplug(HotplugHandler *hotplug_dev, DeviceState *dev,
 963                                   Error **errp)
 964 {
 965     VirtIODevice *vdev = VIRTIO_DEVICE(hotplug_dev);
 966     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 967     SCSIDevice *sd = SCSI_DEVICE(dev);
 968     AioContext *ctx = s->ctx ?: qemu_get_aio_context();
 969
 970     if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) {
 971         virtio_scsi_acquire(s);
 972         virtio_scsi_push_event(s, sd,
 973                                VIRTIO_SCSI_T_TRANSPORT_RESET,
 974                                VIRTIO_SCSI_EVT_RESET_REMOVED);
 975         virtio_scsi_release(s);
 976     }
 977
 978     aio_disable_external(ctx);
 979     qdev_simple_device_unplug_cb(hotplug_dev, dev, errp);
 980     aio_enable_external(ctx);
 981
 982     if (s->ctx) {
 983         virtio_scsi_acquire(s);
 984         /* If other users keep the BlockBackend in the iothread, that's ok */
 985         blk_set_aio_context(sd->conf.blk, qemu_get_aio_context(), NULL);
 986         virtio_scsi_release(s);
 987     }
 988 }
 989
 990 static struct SCSIBusInfo virtio_scsi_scsi_info = {
 991     .tcq = true,
 992     .max_channel = VIRTIO_SCSI_MAX_CHANNEL,
 993     .max_target = VIRTIO_SCSI_MAX_TARGET,
 994     .max_lun = VIRTIO_SCSI_MAX_LUN,
 995
 996     .complete = virtio_scsi_command_complete,
 997     .fail = virtio_scsi_command_failed,
 998     .cancel = virtio_scsi_request_cancelled,
 999     .change = virtio_scsi_change,
1000     .parse_cdb = virtio_scsi_parse_cdb,
1001     .get_sg_list = virtio_scsi_get_sg_list,
1002     .save_request = virtio_scsi_save_request,
1003     .load_request = virtio_scsi_load_request,
1004 };
1005
1006 void virtio_scsi_common_realize(DeviceState *dev,
1007                                 VirtIOHandleOutput ctrl,
1008                                 VirtIOHandleOutput evt,
1009                                 VirtIOHandleOutput cmd,
1010                                 Error **errp)
1011 {
1012     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
1013     VirtIOSCSICommon *s = VIRTIO_SCSI_COMMON(dev);
1014     int i;
1015
1016     virtio_init(vdev, VIRTIO_ID_SCSI, sizeof(VirtIOSCSIConfig));
1017
1018     if (s->conf.num_queues == VIRTIO_SCSI_AUTO_NUM_QUEUES) {
1019         s->conf.num_queues = 1;
1020     }
1021     if (s->conf.num_queues == 0 ||
1022             s->conf.num_queues > VIRTIO_QUEUE_MAX - VIRTIO_SCSI_VQ_NUM_FIXED) {
1023         error_setg(errp, "Invalid number of queues (= %" PRIu32 "), "
1024                          "must be a positive integer less than %d.",
1025                    s->conf.num_queues,
1026                    VIRTIO_QUEUE_MAX - VIRTIO_SCSI_VQ_NUM_FIXED);
1027         virtio_cleanup(vdev);
1028         return;
1029     }
1030     if (s->conf.virtqueue_size <= 2) {
1031         error_setg(errp, "invalid virtqueue_size property (= %" PRIu32 "), "
1032                    "must be > 2", s->conf.virtqueue_size);
1033         return;
1034     }
1035     s->cmd_vqs = g_new0(VirtQueue *, s->conf.num_queues);
1036     s->sense_size = VIRTIO_SCSI_SENSE_DEFAULT_SIZE;
1037     s->cdb_size = VIRTIO_SCSI_CDB_DEFAULT_SIZE;
1038
1039     s->ctrl_vq = virtio_add_queue(vdev, s->conf.virtqueue_size, ctrl);
1040     s->event_vq = virtio_add_queue(vdev, s->conf.virtqueue_size, evt);
1041     for (i = 0; i < s->conf.num_queues; i++) {
1042         s->cmd_vqs[i] = virtio_add_queue(vdev, s->conf.virtqueue_size, cmd);
1043     }
1044 }
1045
1046 static void virtio_scsi_device_realize(DeviceState *dev, Error **errp)
1047 {
1048     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
1049     VirtIOSCSI *s = VIRTIO_SCSI(dev);
1050     Error *err = NULL;
1051
1052     virtio_scsi_common_realize(dev,
1053                                virtio_scsi_handle_ctrl,
1054                                virtio_scsi_handle_event,
1055                                virtio_scsi_handle_cmd,
1056                                &err);
1057     if (err != NULL) {
1058         error_propagate(errp, err);
1059         return;
1060     }
1061
1062     scsi_bus_init_named(&s->bus, sizeof(s->bus), dev,
1063                        &virtio_scsi_scsi_info, vdev->bus_name);
1064     /* override default SCSI bus hotplug-handler, with virtio-scsi's one */
1065     qbus_set_hotplug_handler(BUS(&s->bus), OBJECT(dev));
1066
1067     virtio_scsi_dataplane_setup(s, errp);
1068 }
1069
1070 void virtio_scsi_common_unrealize(DeviceState *dev)
1071 {
1072     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
1073     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
1074     int i;
1075
1076     virtio_delete_queue(vs->ctrl_vq);
1077     virtio_delete_queue(vs->event_vq);
1078     for (i = 0; i < vs->conf.num_queues; i++) {
1079         virtio_delete_queue(vs->cmd_vqs[i]);
1080     }
1081     g_free(vs->cmd_vqs);
1082     virtio_cleanup(vdev);
1083 }
1084
1085 static void virtio_scsi_device_unrealize(DeviceState *dev)
1086 {
1087     VirtIOSCSI *s = VIRTIO_SCSI(dev);
1088
1089     qbus_set_hotplug_handler(BUS(&s->bus), NULL);
1090     virtio_scsi_common_unrealize(dev);
1091 }
1092
1093 static Property virtio_scsi_properties[] = {
1094     DEFINE_PROP_UINT32("num_queues", VirtIOSCSI, parent_obj.conf.num_queues,
1095                        VIRTIO_SCSI_AUTO_NUM_QUEUES),
1096     DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSI,
1097                                          parent_obj.conf.virtqueue_size, 256),
1098     DEFINE_PROP_BOOL("seg_max_adjust", VirtIOSCSI,
1099                       parent_obj.conf.seg_max_adjust, true),
1100     DEFINE_PROP_UINT32("max_sectors", VirtIOSCSI, parent_obj.conf.max_sectors,
1101                                                   0xFFFF),
1102     DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSI, parent_obj.conf.cmd_per_lun,
1103                                                   128),
1104     DEFINE_PROP_BIT("hotplug", VirtIOSCSI, host_features,
1105                                            VIRTIO_SCSI_F_HOTPLUG, true),
1106     DEFINE_PROP_BIT("param_change", VirtIOSCSI, host_features,
1107                                                 VIRTIO_SCSI_F_CHANGE, true),
1108     DEFINE_PROP_LINK("iothread", VirtIOSCSI, parent_obj.conf.iothread,
1109                      TYPE_IOTHREAD, IOThread *),
1110     DEFINE_PROP_END_OF_LIST(),
1111 };
1112
1113 static const VMStateDescription vmstate_virtio_scsi = {
1114     .name = "virtio-scsi",
1115     .minimum_version_id = 1,
1116     .version_id = 1,
1117     .fields = (VMStateField[]) {
1118         VMSTATE_VIRTIO_DEVICE,
1119         VMSTATE_END_OF_LIST()
1120     },
1121 };
1122
1123 static void virtio_scsi_common_class_init(ObjectClass *klass, void *data)
1124 {
1125     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
1126     DeviceClass *dc = DEVICE_CLASS(klass);
1127
1128     vdc->get_config = virtio_scsi_get_config;
1129     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1130 }
1131
1132 static void virtio_scsi_class_init(ObjectClass *klass, void *data)
1133 {
1134     DeviceClass *dc = DEVICE_CLASS(klass);
1135     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
1136     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
1137
1138     device_class_set_props(dc, virtio_scsi_properties);
1139     dc->vmsd = &vmstate_virtio_scsi;
1140     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1141     vdc->realize = virtio_scsi_device_realize;
1142     vdc->unrealize = virtio_scsi_device_unrealize;
1143     vdc->set_config = virtio_scsi_set_config;
1144     vdc->get_features = virtio_scsi_get_features;
1145     vdc->reset = virtio_scsi_reset;
1146     vdc->start_ioeventfd = virtio_scsi_dataplane_start;
1147     vdc->stop_ioeventfd = virtio_scsi_dataplane_stop;
1148     hc->pre_plug = virtio_scsi_pre_hotplug;
1149     hc->plug = virtio_scsi_hotplug;
1150     hc->unplug = virtio_scsi_hotunplug;
1151 }
1152
1153 static const TypeInfo virtio_scsi_common_info = {
1154     .name = TYPE_VIRTIO_SCSI_COMMON,
1155     .parent = TYPE_VIRTIO_DEVICE,
1156     .instance_size = sizeof(VirtIOSCSICommon),
1157     .abstract = true,
1158     .class_init = virtio_scsi_common_class_init,
1159 };
1160
1161 static const TypeInfo virtio_scsi_info = {
1162     .name = TYPE_VIRTIO_SCSI,
1163     .parent = TYPE_VIRTIO_SCSI_COMMON,
1164     .instance_size = sizeof(VirtIOSCSI),
1165     .class_init = virtio_scsi_class_init,
1166     .interfaces = (InterfaceInfo[]) {
1167         { TYPE_HOTPLUG_HANDLER },
1168         { }
1169     }
1170 };
1171
1172 static void virtio_register_types(void)
1173 {
1174     type_register_static(&virtio_scsi_common_info);
1175     type_register_static(&virtio_scsi_info);
1176 }
1177
1178 type_init(virtio_register_types)