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 "standard-headers/linux/virtio_ids.h"
  18 #include "hw/virtio/virtio-scsi.h"
  19 #include "qemu/error-report.h"
  20 #include "qemu/iov.h"
  21 #include "sysemu/block-backend.h"
  22 #include <hw/scsi/scsi.h>
  23 #include <block/scsi.h>
  24 #include <hw/virtio/virtio-bus.h>
  25 #include "hw/virtio/virtio-access.h"
  26
  27 static inline int virtio_scsi_get_lun(uint8_t *lun)
  28 {
  29     return ((lun[2] << 8) | lun[3]) & 0x3FFF;
  30 }
  31
  32 static inline SCSIDevice *virtio_scsi_device_find(VirtIOSCSI *s, uint8_t *lun)
  33 {
  34     if (lun[0] != 1) {
  35         return NULL;
  36     }
  37     if (lun[2] != 0 && !(lun[2] >= 0x40 && lun[2] < 0x80)) {
  38         return NULL;
  39     }
  40     return scsi_device_find(&s->bus, 0, lun[1], virtio_scsi_get_lun(lun));
  41 }
  42
  43 void virtio_scsi_init_req(VirtIOSCSI *s, VirtQueue *vq, VirtIOSCSIReq *req)
  44 {
  45     const size_t zero_skip =
  46         offsetof(VirtIOSCSIReq, resp_iov) + sizeof(req->resp_iov);
  47
  48     req->vq = vq;
  49     req->dev = s;
  50     qemu_sglist_init(&req->qsgl, DEVICE(s), 8, &address_space_memory);
  51     qemu_iovec_init(&req->resp_iov, 1);
  52     memset((uint8_t *)req + zero_skip, 0, sizeof(*req) - zero_skip);
  53 }
  54
  55 void virtio_scsi_free_req(VirtIOSCSIReq *req)
  56 {
  57     qemu_iovec_destroy(&req->resp_iov);
  58     qemu_sglist_destroy(&req->qsgl);
  59     g_free(req);
  60 }
  61
  62 static void virtio_scsi_complete_req(VirtIOSCSIReq *req)
  63 {
  64     VirtIOSCSI *s = req->dev;
  65     VirtQueue *vq = req->vq;
  66     VirtIODevice *vdev = VIRTIO_DEVICE(s);
  67
  68     qemu_iovec_from_buf(&req->resp_iov, 0, &req->resp, req->resp_size);
  69     virtqueue_push(vq, &req->elem, req->qsgl.size + req->resp_iov.size);
  70     if (s->dataplane_started) {
  71         virtio_scsi_dataplane_notify(vdev, req);
  72     } else {
  73         virtio_notify(vdev, vq);
  74     }
  75
  76     if (req->sreq) {
  77         req->sreq->hba_private = NULL;
  78         scsi_req_unref(req->sreq);
  79     }
  80     virtio_scsi_free_req(req);
  81 }
  82
  83 static void virtio_scsi_bad_req(void)
  84 {
  85     error_report("wrong size for virtio-scsi headers");
  86     exit(1);
  87 }
  88
  89 static size_t qemu_sgl_concat(VirtIOSCSIReq *req, struct iovec *iov,
  90                               hwaddr *addr, int num, size_t skip)
  91 {
  92     QEMUSGList *qsgl = &req->qsgl;
  93     size_t copied = 0;
  94
  95     while (num) {
  96         if (skip >= iov->iov_len) {
  97             skip -= iov->iov_len;
  98         } else {
  99             qemu_sglist_add(qsgl, *addr + skip, iov->iov_len - skip);
 100             copied += iov->iov_len - skip;
 101             skip = 0;
 102         }
 103         iov++;
 104         addr++;
 105         num--;
 106     }
 107
 108     assert(skip == 0);
 109     return copied;
 110 }
 111
 112 static int virtio_scsi_parse_req(VirtIOSCSIReq *req,
 113                                  unsigned req_size, unsigned resp_size)
 114 {
 115     VirtIODevice *vdev = (VirtIODevice *) req->dev;
 116     size_t in_size, out_size;
 117
 118     if (iov_to_buf(req->elem.out_sg, req->elem.out_num, 0,
 119                    &req->req, req_size) < req_size) {
 120         return -EINVAL;
 121     }
 122
 123     if (qemu_iovec_concat_iov(&req->resp_iov,
 124                               req->elem.in_sg, req->elem.in_num, 0,
 125                               resp_size) < resp_size) {
 126         return -EINVAL;
 127     }
 128
 129     req->resp_size = resp_size;
 130
 131     /* Old BIOSes left some padding by mistake after the req_size/resp_size.
 132      * As a workaround, always consider the first buffer as the virtio-scsi
 133      * request/response, making the payload start at the second element
 134      * of the iovec.
 135      *
 136      * The actual length of the response header, stored in req->resp_size,
 137      * does not change.
 138      *
 139      * TODO: always disable this workaround for virtio 1.0 devices.
 140      */
 141     if (!virtio_vdev_has_feature(vdev, VIRTIO_F_ANY_LAYOUT)) {
 142         if (req->elem.out_num) {
 143             req_size = req->elem.out_sg[0].iov_len;
 144         }
 145         if (req->elem.in_num) {
 146             resp_size = req->elem.in_sg[0].iov_len;
 147         }
 148     }
 149
 150     out_size = qemu_sgl_concat(req, req->elem.out_sg,
 151                                &req->elem.out_addr[0], req->elem.out_num,
 152                                req_size);
 153     in_size = qemu_sgl_concat(req, req->elem.in_sg,
 154                               &req->elem.in_addr[0], req->elem.in_num,
 155                               resp_size);
 156
 157     if (out_size && in_size) {
 158         return -ENOTSUP;
 159     }
 160
 161     if (out_size) {
 162         req->mode = SCSI_XFER_TO_DEV;
 163     } else if (in_size) {
 164         req->mode = SCSI_XFER_FROM_DEV;
 165     }
 166
 167     return 0;
 168 }
 169
 170 static VirtIOSCSIReq *virtio_scsi_pop_req(VirtIOSCSI *s, VirtQueue *vq)
 171 {
 172     VirtIOSCSICommon *vs = (VirtIOSCSICommon *)s;
 173     VirtIOSCSIReq *req;
 174
 175     req = virtqueue_pop(vq, sizeof(VirtIOSCSIReq) + vs->cdb_size);
 176     if (!req) {
 177         return NULL;
 178     }
 179     virtio_scsi_init_req(s, vq, req);
 180     return req;
 181 }
 182
 183 static void virtio_scsi_save_request(QEMUFile *f, SCSIRequest *sreq)
 184 {
 185     VirtIOSCSIReq *req = sreq->hba_private;
 186     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(req->dev);
 187     uint32_t n = virtio_queue_get_id(req->vq) - 2;
 188
 189     assert(n < vs->conf.num_queues);
 190     qemu_put_be32s(f, &n);
 191     qemu_put_virtqueue_element(f, &req->elem);
 192 }
 193
 194 static void *virtio_scsi_load_request(QEMUFile *f, SCSIRequest *sreq)
 195 {
 196     SCSIBus *bus = sreq->bus;
 197     VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus);
 198     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
 199     VirtIOSCSIReq *req;
 200     uint32_t n;
 201
 202     qemu_get_be32s(f, &n);
 203     assert(n < vs->conf.num_queues);
 204     req = qemu_get_virtqueue_element(f, sizeof(VirtIOSCSIReq) + vs->cdb_size);
 205     virtio_scsi_init_req(s, vs->cmd_vqs[n], req);
 206
 207     if (virtio_scsi_parse_req(req, sizeof(VirtIOSCSICmdReq) + vs->cdb_size,
 208                               sizeof(VirtIOSCSICmdResp) + vs->sense_size) < 0) {
 209         error_report("invalid SCSI request migration data");
 210         exit(1);
 211     }
 212
 213     scsi_req_ref(sreq);
 214     req->sreq = sreq;
 215     if (req->sreq->cmd.mode != SCSI_XFER_NONE) {
 216         assert(req->sreq->cmd.mode == req->mode);
 217     }
 218     return req;
 219 }
 220
 221 typedef struct {
 222     Notifier        notifier;
 223     VirtIOSCSIReq  *tmf_req;
 224 } VirtIOSCSICancelNotifier;
 225
 226 static void virtio_scsi_cancel_notify(Notifier *notifier, void *data)
 227 {
 228     VirtIOSCSICancelNotifier *n = container_of(notifier,
 229                                                VirtIOSCSICancelNotifier,
 230                                                notifier);
 231
 232     if (--n->tmf_req->remaining == 0) {
 233         virtio_scsi_complete_req(n->tmf_req);
 234     }
 235     g_free(n);
 236 }
 237
 238 /* Return 0 if the request is ready to be completed and return to guest;
 239  * -EINPROGRESS if the request is submitted and will be completed later, in the
 240  *  case of async cancellation. */
 241 static int virtio_scsi_do_tmf(VirtIOSCSI *s, VirtIOSCSIReq *req)
 242 {
 243     SCSIDevice *d = virtio_scsi_device_find(s, req->req.tmf.lun);
 244     SCSIRequest *r, *next;
 245     BusChild *kid;
 246     int target;
 247     int ret = 0;
 248
 249     if (s->dataplane_started && d) {
 250         assert(blk_get_aio_context(d->conf.blk) == s->ctx);
 251     }
 252     /* Here VIRTIO_SCSI_S_OK means "FUNCTION COMPLETE".  */
 253     req->resp.tmf.response = VIRTIO_SCSI_S_OK;
 254
 255     virtio_tswap32s(VIRTIO_DEVICE(s), &req->req.tmf.subtype);
 256     switch (req->req.tmf.subtype) {
 257     case VIRTIO_SCSI_T_TMF_ABORT_TASK:
 258     case VIRTIO_SCSI_T_TMF_QUERY_TASK:
 259         if (!d) {
 260             goto fail;
 261         }
 262         if (d->lun != virtio_scsi_get_lun(req->req.tmf.lun)) {
 263             goto incorrect_lun;
 264         }
 265         QTAILQ_FOREACH_SAFE(r, &d->requests, next, next) {
 266             VirtIOSCSIReq *cmd_req = r->hba_private;
 267             if (cmd_req && cmd_req->req.cmd.tag == req->req.tmf.tag) {
 268                 break;
 269             }
 270         }
 271         if (r) {
 272             /*
 273              * Assert that the request has not been completed yet, we
 274              * check for it in the loop above.
 275              */
 276             assert(r->hba_private);
 277             if (req->req.tmf.subtype == VIRTIO_SCSI_T_TMF_QUERY_TASK) {
 278                 /* "If the specified command is present in the task set, then
 279                  * return a service response set to FUNCTION SUCCEEDED".
 280                  */
 281                 req->resp.tmf.response = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
 282             } else {
 283                 VirtIOSCSICancelNotifier *notifier;
 284
 285                 req->remaining = 1;
 286                 notifier = g_new(VirtIOSCSICancelNotifier, 1);
 287                 notifier->tmf_req = req;
 288                 notifier->notifier.notify = virtio_scsi_cancel_notify;
 289                 scsi_req_cancel_async(r, &notifier->notifier);
 290                 ret = -EINPROGRESS;
 291             }
 292         }
 293         break;
 294
 295     case VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET:
 296         if (!d) {
 297             goto fail;
 298         }
 299         if (d->lun != virtio_scsi_get_lun(req->req.tmf.lun)) {
 300             goto incorrect_lun;
 301         }
 302         s->resetting++;
 303         qdev_reset_all(&d->qdev);
 304         s->resetting--;
 305         break;
 306
 307     case VIRTIO_SCSI_T_TMF_ABORT_TASK_SET:
 308     case VIRTIO_SCSI_T_TMF_CLEAR_TASK_SET:
 309     case VIRTIO_SCSI_T_TMF_QUERY_TASK_SET:
 310         if (!d) {
 311             goto fail;
 312         }
 313         if (d->lun != virtio_scsi_get_lun(req->req.tmf.lun)) {
 314             goto incorrect_lun;
 315         }
 316
 317         /* Add 1 to "remaining" until virtio_scsi_do_tmf returns.
 318          * This way, if the bus starts calling back to the notifiers
 319          * even before we finish the loop, virtio_scsi_cancel_notify
 320          * will not complete the TMF too early.
 321          */
 322         req->remaining = 1;
 323         QTAILQ_FOREACH_SAFE(r, &d->requests, next, next) {
 324             if (r->hba_private) {
 325                 if (req->req.tmf.subtype == VIRTIO_SCSI_T_TMF_QUERY_TASK_SET) {
 326                     /* "If there is any command present in the task set, then
 327                      * return a service response set to FUNCTION SUCCEEDED".
 328                      */
 329                     req->resp.tmf.response = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
 330                     break;
 331                 } else {
 332                     VirtIOSCSICancelNotifier *notifier;
 333
 334                     req->remaining++;
 335                     notifier = g_new(VirtIOSCSICancelNotifier, 1);
 336                     notifier->notifier.notify = virtio_scsi_cancel_notify;
 337                     notifier->tmf_req = req;
 338                     scsi_req_cancel_async(r, &notifier->notifier);
 339                 }
 340             }
 341         }
 342         if (--req->remaining > 0) {
 343             ret = -EINPROGRESS;
 344         }
 345         break;
 346
 347     case VIRTIO_SCSI_T_TMF_I_T_NEXUS_RESET:
 348         target = req->req.tmf.lun[1];
 349         s->resetting++;
 350         QTAILQ_FOREACH(kid, &s->bus.qbus.children, sibling) {
 351              d = SCSI_DEVICE(kid->child);
 352              if (d->channel == 0 && d->id == target) {
 353                 qdev_reset_all(&d->qdev);
 354              }
 355         }
 356         s->resetting--;
 357         break;
 358
 359     case VIRTIO_SCSI_T_TMF_CLEAR_ACA:
 360     default:
 361         req->resp.tmf.response = VIRTIO_SCSI_S_FUNCTION_REJECTED;
 362         break;
 363     }
 364
 365     return ret;
 366
 367 incorrect_lun:
 368     req->resp.tmf.response = VIRTIO_SCSI_S_INCORRECT_LUN;
 369     return ret;
 370
 371 fail:
 372     req->resp.tmf.response = VIRTIO_SCSI_S_BAD_TARGET;
 373     return ret;
 374 }
 375
 376 void virtio_scsi_handle_ctrl_req(VirtIOSCSI *s, VirtIOSCSIReq *req)
 377 {
 378     VirtIODevice *vdev = (VirtIODevice *)s;
 379     uint32_t type;
 380     int r = 0;
 381
 382     if (iov_to_buf(req->elem.out_sg, req->elem.out_num, 0,
 383                 &type, sizeof(type)) < sizeof(type)) {
 384         virtio_scsi_bad_req();
 385         return;
 386     }
 387
 388     virtio_tswap32s(vdev, &type);
 389     if (type == VIRTIO_SCSI_T_TMF) {
 390         if (virtio_scsi_parse_req(req, sizeof(VirtIOSCSICtrlTMFReq),
 391                     sizeof(VirtIOSCSICtrlTMFResp)) < 0) {
 392             virtio_scsi_bad_req();
 393         } else {
 394             r = virtio_scsi_do_tmf(s, req);
 395         }
 396
 397     } else if (type == VIRTIO_SCSI_T_AN_QUERY ||
 398                type == VIRTIO_SCSI_T_AN_SUBSCRIBE) {
 399         if (virtio_scsi_parse_req(req, sizeof(VirtIOSCSICtrlANReq),
 400                     sizeof(VirtIOSCSICtrlANResp)) < 0) {
 401             virtio_scsi_bad_req();
 402         } else {
 403             req->resp.an.event_actual = 0;
 404             req->resp.an.response = VIRTIO_SCSI_S_OK;
 405         }
 406     }
 407     if (r == 0) {
 408         virtio_scsi_complete_req(req);
 409     } else {
 410         assert(r == -EINPROGRESS);
 411     }
 412 }
 413
 414 static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
 415 {
 416     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 417     VirtIOSCSIReq *req;
 418
 419     if (s->ctx && !s->dataplane_started) {
 420         virtio_scsi_dataplane_start(s);
 421         return;
 422     }
 423     while ((req = virtio_scsi_pop_req(s, vq))) {
 424         virtio_scsi_handle_ctrl_req(s, req);
 425     }
 426 }
 427
 428 static void virtio_scsi_complete_cmd_req(VirtIOSCSIReq *req)
 429 {
 430     /* Sense data is not in req->resp and is copied separately
 431      * in virtio_scsi_command_complete.
 432      */
 433     req->resp_size = sizeof(VirtIOSCSICmdResp);
 434     virtio_scsi_complete_req(req);
 435 }
 436
 437 static void virtio_scsi_command_complete(SCSIRequest *r, uint32_t status,
 438                                          size_t resid)
 439 {
 440     VirtIOSCSIReq *req = r->hba_private;
 441     uint8_t sense[SCSI_SENSE_BUF_SIZE];
 442     uint32_t sense_len;
 443     VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
 444
 445     if (r->io_canceled) {
 446         return;
 447     }
 448
 449     req->resp.cmd.response = VIRTIO_SCSI_S_OK;
 450     req->resp.cmd.status = status;
 451     if (req->resp.cmd.status == GOOD) {
 452         req->resp.cmd.resid = virtio_tswap32(vdev, resid);
 453     } else {
 454         req->resp.cmd.resid = 0;
 455         sense_len = scsi_req_get_sense(r, sense, sizeof(sense));
 456         sense_len = MIN(sense_len, req->resp_iov.size - sizeof(req->resp.cmd));
 457         qemu_iovec_from_buf(&req->resp_iov, sizeof(req->resp.cmd),
 458                             sense, sense_len);
 459         req->resp.cmd.sense_len = virtio_tswap32(vdev, sense_len);
 460     }
 461     virtio_scsi_complete_cmd_req(req);
 462 }
 463
 464 static int virtio_scsi_parse_cdb(SCSIDevice *dev, SCSICommand *cmd,
 465                                  uint8_t *buf, void *hba_private)
 466 {
 467     VirtIOSCSIReq *req = hba_private;
 468
 469     if (cmd->len == 0) {
 470         cmd->len = MIN(VIRTIO_SCSI_CDB_DEFAULT_SIZE, SCSI_CMD_BUF_SIZE);
 471         memcpy(cmd->buf, buf, cmd->len);
 472     }
 473
 474     /* Extract the direction and mode directly from the request, for
 475      * host device passthrough.
 476      */
 477     cmd->xfer = req->qsgl.size;
 478     cmd->mode = req->mode;
 479     return 0;
 480 }
 481
 482 static QEMUSGList *virtio_scsi_get_sg_list(SCSIRequest *r)
 483 {
 484     VirtIOSCSIReq *req = r->hba_private;
 485
 486     return &req->qsgl;
 487 }
 488
 489 static void virtio_scsi_request_cancelled(SCSIRequest *r)
 490 {
 491     VirtIOSCSIReq *req = r->hba_private;
 492
 493     if (!req) {
 494         return;
 495     }
 496     if (req->dev->resetting) {
 497         req->resp.cmd.response = VIRTIO_SCSI_S_RESET;
 498     } else {
 499         req->resp.cmd.response = VIRTIO_SCSI_S_ABORTED;
 500     }
 501     virtio_scsi_complete_cmd_req(req);
 502 }
 503
 504 static void virtio_scsi_fail_cmd_req(VirtIOSCSIReq *req)
 505 {
 506     req->resp.cmd.response = VIRTIO_SCSI_S_FAILURE;
 507     virtio_scsi_complete_cmd_req(req);
 508 }
 509
 510 bool virtio_scsi_handle_cmd_req_prepare(VirtIOSCSI *s, VirtIOSCSIReq *req)
 511 {
 512     VirtIOSCSICommon *vs = &s->parent_obj;
 513     SCSIDevice *d;
 514     int rc;
 515
 516     rc = virtio_scsi_parse_req(req, sizeof(VirtIOSCSICmdReq) + vs->cdb_size,
 517                                sizeof(VirtIOSCSICmdResp) + vs->sense_size);
 518     if (rc < 0) {
 519         if (rc == -ENOTSUP) {
 520             virtio_scsi_fail_cmd_req(req);
 521         } else {
 522             virtio_scsi_bad_req();
 523         }
 524         return false;
 525     }
 526
 527     d = virtio_scsi_device_find(s, req->req.cmd.lun);
 528     if (!d) {
 529         req->resp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET;
 530         virtio_scsi_complete_cmd_req(req);
 531         return false;
 532     }
 533     if (s->dataplane_started) {
 534         assert(blk_get_aio_context(d->conf.blk) == s->ctx);
 535     }
 536     req->sreq = scsi_req_new(d, req->req.cmd.tag,
 537                              virtio_scsi_get_lun(req->req.cmd.lun),
 538                              req->req.cmd.cdb, req);
 539
 540     if (req->sreq->cmd.mode != SCSI_XFER_NONE
 541         && (req->sreq->cmd.mode != req->mode ||
 542             req->sreq->cmd.xfer > req->qsgl.size)) {
 543         req->resp.cmd.response = VIRTIO_SCSI_S_OVERRUN;
 544         virtio_scsi_complete_cmd_req(req);
 545         return false;
 546     }
 547     scsi_req_ref(req->sreq);
 548     blk_io_plug(d->conf.blk);
 549     return true;
 550 }
 551
 552 void virtio_scsi_handle_cmd_req_submit(VirtIOSCSI *s, VirtIOSCSIReq *req)
 553 {
 554     SCSIRequest *sreq = req->sreq;
 555     if (scsi_req_enqueue(sreq)) {
 556         scsi_req_continue(sreq);
 557     }
 558     blk_io_unplug(sreq->dev->conf.blk);
 559     scsi_req_unref(sreq);
 560 }
 561
 562 static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
 563 {
 564     /* use non-QOM casts in the data path */
 565     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 566     VirtIOSCSIReq *req, *next;
 567     QTAILQ_HEAD(, VirtIOSCSIReq) reqs = QTAILQ_HEAD_INITIALIZER(reqs);
 568
 569     if (s->ctx && !s->dataplane_started) {
 570         virtio_scsi_dataplane_start(s);
 571         return;
 572     }
 573     while ((req = virtio_scsi_pop_req(s, vq))) {
 574         if (virtio_scsi_handle_cmd_req_prepare(s, req)) {
 575             QTAILQ_INSERT_TAIL(&reqs, req, next);
 576         }
 577     }
 578
 579     QTAILQ_FOREACH_SAFE(req, &reqs, next, next) {
 580         virtio_scsi_handle_cmd_req_submit(s, req);
 581     }
 582 }
 583
 584 static void virtio_scsi_get_config(VirtIODevice *vdev,
 585                                    uint8_t *config)
 586 {
 587     VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config;
 588     VirtIOSCSICommon *s = VIRTIO_SCSI_COMMON(vdev);
 589
 590     virtio_stl_p(vdev, &scsiconf->num_queues, s->conf.num_queues);
 591     virtio_stl_p(vdev, &scsiconf->seg_max, 128 - 2);
 592     virtio_stl_p(vdev, &scsiconf->max_sectors, s->conf.max_sectors);
 593     virtio_stl_p(vdev, &scsiconf->cmd_per_lun, s->conf.cmd_per_lun);
 594     virtio_stl_p(vdev, &scsiconf->event_info_size, sizeof(VirtIOSCSIEvent));
 595     virtio_stl_p(vdev, &scsiconf->sense_size, s->sense_size);
 596     virtio_stl_p(vdev, &scsiconf->cdb_size, s->cdb_size);
 597     virtio_stw_p(vdev, &scsiconf->max_channel, VIRTIO_SCSI_MAX_CHANNEL);
 598     virtio_stw_p(vdev, &scsiconf->max_target, VIRTIO_SCSI_MAX_TARGET);
 599     virtio_stl_p(vdev, &scsiconf->max_lun, VIRTIO_SCSI_MAX_LUN);
 600 }
 601
 602 static void virtio_scsi_set_config(VirtIODevice *vdev,
 603                                    const uint8_t *config)
 604 {
 605     VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config;
 606     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev);
 607
 608     if ((uint32_t) virtio_ldl_p(vdev, &scsiconf->sense_size) >= 65536 ||
 609         (uint32_t) virtio_ldl_p(vdev, &scsiconf->cdb_size) >= 256) {
 610         error_report("bad data written to virtio-scsi configuration space");
 611         exit(1);
 612     }
 613
 614     vs->sense_size = virtio_ldl_p(vdev, &scsiconf->sense_size);
 615     vs->cdb_size = virtio_ldl_p(vdev, &scsiconf->cdb_size);
 616 }
 617
 618 static uint64_t virtio_scsi_get_features(VirtIODevice *vdev,
 619                                          uint64_t requested_features,
 620                                          Error **errp)
 621 {
 622     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 623
 624     /* Firstly sync all virtio-scsi possible supported features */
 625     requested_features |= s->host_features;
 626     return requested_features;
 627 }
 628
 629 static void virtio_scsi_reset(VirtIODevice *vdev)
 630 {
 631     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 632     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev);
 633
 634     if (s->ctx) {
 635         virtio_scsi_dataplane_stop(s);
 636     }
 637     s->resetting++;
 638     qbus_reset_all(&s->bus.qbus);
 639     s->resetting--;
 640
 641     vs->sense_size = VIRTIO_SCSI_SENSE_DEFAULT_SIZE;
 642     vs->cdb_size = VIRTIO_SCSI_CDB_DEFAULT_SIZE;
 643     s->events_dropped = false;
 644 }
 645
 646 /* The device does not have anything to save beyond the virtio data.
 647  * Request data is saved with callbacks from SCSI devices.
 648  */
 649 static void virtio_scsi_save(QEMUFile *f, void *opaque)
 650 {
 651     VirtIODevice *vdev = VIRTIO_DEVICE(opaque);
 652     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 653
 654     if (s->dataplane_started) {
 655         virtio_scsi_dataplane_stop(s);
 656     }
 657     virtio_save(vdev, f);
 658 }
 659
 660 static int virtio_scsi_load(QEMUFile *f, void *opaque, int version_id)
 661 {
 662     VirtIODevice *vdev = VIRTIO_DEVICE(opaque);
 663     int ret;
 664
 665     ret = virtio_load(vdev, f, version_id);
 666     if (ret) {
 667         return ret;
 668     }
 669     return 0;
 670 }
 671
 672 void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev,
 673                             uint32_t event, uint32_t reason)
 674 {
 675     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
 676     VirtIOSCSIReq *req;
 677     VirtIOSCSIEvent *evt;
 678     VirtIODevice *vdev = VIRTIO_DEVICE(s);
 679
 680     if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
 681         return;
 682     }
 683
 684     if (s->dataplane_started) {
 685         assert(s->ctx);
 686         aio_context_acquire(s->ctx);
 687     }
 688
 689     req = virtio_scsi_pop_req(s, vs->event_vq);
 690     if (!req) {
 691         s->events_dropped = true;
 692         goto out;
 693     }
 694
 695     if (s->events_dropped) {
 696         event |= VIRTIO_SCSI_T_EVENTS_MISSED;
 697         s->events_dropped = false;
 698     }
 699
 700     if (virtio_scsi_parse_req(req, 0, sizeof(VirtIOSCSIEvent))) {
 701         virtio_scsi_bad_req();
 702     }
 703
 704     evt = &req->resp.event;
 705     memset(evt, 0, sizeof(VirtIOSCSIEvent));
 706     evt->event = virtio_tswap32(vdev, event);
 707     evt->reason = virtio_tswap32(vdev, reason);
 708     if (!dev) {
 709         assert(event == VIRTIO_SCSI_T_EVENTS_MISSED);
 710     } else {
 711         evt->lun[0] = 1;
 712         evt->lun[1] = dev->id;
 713
 714         /* Linux wants us to keep the same encoding we use for REPORT LUNS.  */
 715         if (dev->lun >= 256) {
 716             evt->lun[2] = (dev->lun >> 8) | 0x40;
 717         }
 718         evt->lun[3] = dev->lun & 0xFF;
 719     }
 720     virtio_scsi_complete_req(req);
 721 out:
 722     if (s->dataplane_started) {
 723         aio_context_release(s->ctx);
 724     }
 725 }
 726
 727 static void virtio_scsi_handle_event(VirtIODevice *vdev, VirtQueue *vq)
 728 {
 729     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 730
 731     if (s->ctx && !s->dataplane_started) {
 732         virtio_scsi_dataplane_start(s);
 733         return;
 734     }
 735     if (s->events_dropped) {
 736         virtio_scsi_push_event(s, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
 737     }
 738 }
 739
 740 static void virtio_scsi_change(SCSIBus *bus, SCSIDevice *dev, SCSISense sense)
 741 {
 742     VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus);
 743     VirtIODevice *vdev = VIRTIO_DEVICE(s);
 744
 745     if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_CHANGE) &&
 746         dev->type != TYPE_ROM) {
 747         virtio_scsi_push_event(s, dev, VIRTIO_SCSI_T_PARAM_CHANGE,
 748                                sense.asc | (sense.ascq << 8));
 749     }
 750 }
 751
 752 static void virtio_scsi_blk_insert_notifier(Notifier *n, void *data)
 753 {
 754     VirtIOSCSIBlkChangeNotifier *cn = DO_UPCAST(VirtIOSCSIBlkChangeNotifier,
 755                                                 n, n);
 756     assert(cn->sd->conf.blk == data);
 757     blk_op_block_all(cn->sd->conf.blk, cn->s->blocker);
 758 }
 759
 760 static void virtio_scsi_blk_remove_notifier(Notifier *n, void *data)
 761 {
 762     VirtIOSCSIBlkChangeNotifier *cn = DO_UPCAST(VirtIOSCSIBlkChangeNotifier,
 763                                                 n, n);
 764     assert(cn->sd->conf.blk == data);
 765     blk_op_unblock_all(cn->sd->conf.blk, cn->s->blocker);
 766 }
 767
 768 static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState *dev,
 769                                 Error **errp)
 770 {
 771     VirtIODevice *vdev = VIRTIO_DEVICE(hotplug_dev);
 772     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 773     SCSIDevice *sd = SCSI_DEVICE(dev);
 774
 775     if (s->ctx && !s->dataplane_disabled) {
 776         VirtIOSCSIBlkChangeNotifier *insert_notifier, *remove_notifier;
 777
 778         if (blk_op_is_blocked(sd->conf.blk, BLOCK_OP_TYPE_DATAPLANE, errp)) {
 779             return;
 780         }
 781         blk_op_block_all(sd->conf.blk, s->blocker);
 782         aio_context_acquire(s->ctx);
 783         blk_set_aio_context(sd->conf.blk, s->ctx);
 784         aio_context_release(s->ctx);
 785
 786         insert_notifier = g_new0(VirtIOSCSIBlkChangeNotifier, 1);
 787         insert_notifier->n.notify = virtio_scsi_blk_insert_notifier;
 788         insert_notifier->s = s;
 789         insert_notifier->sd = sd;
 790         blk_add_insert_bs_notifier(sd->conf.blk, &insert_notifier->n);
 791         QTAILQ_INSERT_TAIL(&s->insert_notifiers, insert_notifier, next);
 792
 793         remove_notifier = g_new0(VirtIOSCSIBlkChangeNotifier, 1);
 794         remove_notifier->n.notify = virtio_scsi_blk_remove_notifier;
 795         remove_notifier->s = s;
 796         remove_notifier->sd = sd;
 797         blk_add_remove_bs_notifier(sd->conf.blk, &remove_notifier->n);
 798         QTAILQ_INSERT_TAIL(&s->remove_notifiers, remove_notifier, next);
 799     }
 800
 801     if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) {
 802         virtio_scsi_push_event(s, sd,
 803                                VIRTIO_SCSI_T_TRANSPORT_RESET,
 804                                VIRTIO_SCSI_EVT_RESET_RESCAN);
 805     }
 806 }
 807
 808 static void virtio_scsi_hotunplug(HotplugHandler *hotplug_dev, DeviceState *dev,
 809                                   Error **errp)
 810 {
 811     VirtIODevice *vdev = VIRTIO_DEVICE(hotplug_dev);
 812     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 813     SCSIDevice *sd = SCSI_DEVICE(dev);
 814     VirtIOSCSIBlkChangeNotifier *insert_notifier, *remove_notifier;
 815
 816     if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) {
 817         virtio_scsi_push_event(s, sd,
 818                                VIRTIO_SCSI_T_TRANSPORT_RESET,
 819                                VIRTIO_SCSI_EVT_RESET_REMOVED);
 820     }
 821
 822     if (s->ctx) {
 823         blk_op_unblock_all(sd->conf.blk, s->blocker);
 824     }
 825
 826     QTAILQ_FOREACH(insert_notifier, &s->insert_notifiers, next) {
 827         if (insert_notifier->sd == sd) {
 828             notifier_remove(&insert_notifier->n);
 829             QTAILQ_REMOVE(&s->insert_notifiers, insert_notifier, next);
 830             g_free(insert_notifier);
 831             break;
 832         }
 833     }
 834
 835     QTAILQ_FOREACH(remove_notifier, &s->remove_notifiers, next) {
 836         if (remove_notifier->sd == sd) {
 837             notifier_remove(&remove_notifier->n);
 838             QTAILQ_REMOVE(&s->remove_notifiers, remove_notifier, next);
 839             g_free(remove_notifier);
 840             break;
 841         }
 842     }
 843
 844     qdev_simple_device_unplug_cb(hotplug_dev, dev, errp);
 845 }
 846
 847 static struct SCSIBusInfo virtio_scsi_scsi_info = {
 848     .tcq = true,
 849     .max_channel = VIRTIO_SCSI_MAX_CHANNEL,
 850     .max_target = VIRTIO_SCSI_MAX_TARGET,
 851     .max_lun = VIRTIO_SCSI_MAX_LUN,
 852
 853     .complete = virtio_scsi_command_complete,
 854     .cancel = virtio_scsi_request_cancelled,
 855     .change = virtio_scsi_change,
 856     .parse_cdb = virtio_scsi_parse_cdb,
 857     .get_sg_list = virtio_scsi_get_sg_list,
 858     .save_request = virtio_scsi_save_request,
 859     .load_request = virtio_scsi_load_request,
 860 };
 861
 862 void virtio_scsi_common_realize(DeviceState *dev, Error **errp,
 863                                 HandleOutput ctrl, HandleOutput evt,
 864                                 HandleOutput cmd)
 865 {
 866     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
 867     VirtIOSCSICommon *s = VIRTIO_SCSI_COMMON(dev);
 868     int i;
 869
 870     virtio_init(vdev, "virtio-scsi", VIRTIO_ID_SCSI,
 871                 sizeof(VirtIOSCSIConfig));
 872
 873     if (s->conf.num_queues == 0 ||
 874             s->conf.num_queues > VIRTIO_QUEUE_MAX - 2) {
 875         error_setg(errp, "Invalid number of queues (= %" PRIu32 "), "
 876                          "must be a positive integer less than %d.",
 877                    s->conf.num_queues, VIRTIO_QUEUE_MAX - 2);
 878         virtio_cleanup(vdev);
 879         return;
 880     }
 881     s->cmd_vqs = g_new0(VirtQueue *, s->conf.num_queues);
 882     s->sense_size = VIRTIO_SCSI_SENSE_DEFAULT_SIZE;
 883     s->cdb_size = VIRTIO_SCSI_CDB_DEFAULT_SIZE;
 884
 885     s->ctrl_vq = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE,
 886                                   ctrl);
 887     s->event_vq = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE,
 888                                    evt);
 889     for (i = 0; i < s->conf.num_queues; i++) {
 890         s->cmd_vqs[i] = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE,
 891                                          cmd);
 892     }
 893
 894     if (s->conf.iothread) {
 895         virtio_scsi_set_iothread(VIRTIO_SCSI(s), s->conf.iothread);
 896     }
 897 }
 898
 899 static void virtio_scsi_device_realize(DeviceState *dev, Error **errp)
 900 {
 901     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
 902     VirtIOSCSI *s = VIRTIO_SCSI(dev);
 903     static int virtio_scsi_id;
 904     Error *err = NULL;
 905
 906     virtio_scsi_common_realize(dev, &err, virtio_scsi_handle_ctrl,
 907                                virtio_scsi_handle_event,
 908                                virtio_scsi_handle_cmd);
 909     if (err != NULL) {
 910         error_propagate(errp, err);
 911         return;
 912     }
 913
 914     scsi_bus_new(&s->bus, sizeof(s->bus), dev,
 915                  &virtio_scsi_scsi_info, vdev->bus_name);
 916     /* override default SCSI bus hotplug-handler, with virtio-scsi's one */
 917     qbus_set_hotplug_handler(BUS(&s->bus), dev, &error_abort);
 918
 919     if (!dev->hotplugged) {
 920         scsi_bus_legacy_handle_cmdline(&s->bus, &err);
 921         if (err != NULL) {
 922             error_propagate(errp, err);
 923             return;
 924         }
 925     }
 926
 927     register_savevm(dev, "virtio-scsi", virtio_scsi_id++, 1,
 928                     virtio_scsi_save, virtio_scsi_load, s);
 929
 930     error_setg(&s->blocker, "block device is in use by data plane");
 931
 932     QTAILQ_INIT(&s->insert_notifiers);
 933     QTAILQ_INIT(&s->remove_notifiers);
 934 }
 935
 936 static void virtio_scsi_instance_init(Object *obj)
 937 {
 938     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(obj);
 939
 940     object_property_add_link(obj, "iothread", TYPE_IOTHREAD,
 941                              (Object **)&vs->conf.iothread,
 942                              qdev_prop_allow_set_link_before_realize,
 943                              OBJ_PROP_LINK_UNREF_ON_RELEASE, &error_abort);
 944 }
 945
 946 void virtio_scsi_common_unrealize(DeviceState *dev, Error **errp)
 947 {
 948     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
 949     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
 950
 951     g_free(vs->cmd_vqs);
 952     virtio_cleanup(vdev);
 953 }
 954
 955 static void virtio_scsi_device_unrealize(DeviceState *dev, Error **errp)
 956 {
 957     VirtIOSCSI *s = VIRTIO_SCSI(dev);
 958
 959     error_free(s->blocker);
 960
 961     unregister_savevm(dev, "virtio-scsi", s);
 962     virtio_scsi_common_unrealize(dev, errp);
 963 }
 964
 965 static Property virtio_scsi_properties[] = {
 966     DEFINE_PROP_UINT32("num_queues", VirtIOSCSI, parent_obj.conf.num_queues, 1),
 967     DEFINE_PROP_UINT32("max_sectors", VirtIOSCSI, parent_obj.conf.max_sectors,
 968                                                   0xFFFF),
 969     DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSI, parent_obj.conf.cmd_per_lun,
 970                                                   128),
 971     DEFINE_PROP_BIT("hotplug", VirtIOSCSI, host_features,
 972                                            VIRTIO_SCSI_F_HOTPLUG, true),
 973     DEFINE_PROP_BIT("param_change", VirtIOSCSI, host_features,
 974                                                 VIRTIO_SCSI_F_CHANGE, true),
 975     DEFINE_PROP_END_OF_LIST(),
 976 };
 977
 978 static void virtio_scsi_common_class_init(ObjectClass *klass, void *data)
 979 {
 980     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
 981     DeviceClass *dc = DEVICE_CLASS(klass);
 982
 983     vdc->get_config = virtio_scsi_get_config;
 984     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
 985 }
 986
 987 static void virtio_scsi_class_init(ObjectClass *klass, void *data)
 988 {
 989     DeviceClass *dc = DEVICE_CLASS(klass);
 990     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
 991     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
 992
 993     dc->props = virtio_scsi_properties;
 994     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
 995     vdc->realize = virtio_scsi_device_realize;
 996     vdc->unrealize = virtio_scsi_device_unrealize;
 997     vdc->set_config = virtio_scsi_set_config;
 998     vdc->get_features = virtio_scsi_get_features;
 999     vdc->reset = virtio_scsi_reset;
1000     hc->plug = virtio_scsi_hotplug;
1001     hc->unplug = virtio_scsi_hotunplug;
1002 }
1003
1004 static const TypeInfo virtio_scsi_common_info = {
1005     .name = TYPE_VIRTIO_SCSI_COMMON,
1006     .parent = TYPE_VIRTIO_DEVICE,
1007     .instance_size = sizeof(VirtIOSCSICommon),
1008     .abstract = true,
1009     .class_init = virtio_scsi_common_class_init,
1010 };
1011
1012 static const TypeInfo virtio_scsi_info = {
1013     .name = TYPE_VIRTIO_SCSI,
1014     .parent = TYPE_VIRTIO_SCSI_COMMON,
1015     .instance_size = sizeof(VirtIOSCSI),
1016     .instance_init = virtio_scsi_instance_init,
1017     .class_init = virtio_scsi_class_init,
1018     .interfaces = (InterfaceInfo[]) {
1019         { TYPE_HOTPLUG_HANDLER },
1020         { }
1021     }
1022 };
1023
1024 static void virtio_register_types(void)
1025 {
1026     type_register_static(&virtio_scsi_common_info);
1027     type_register_static(&virtio_scsi_info);
1028 }
1029
1030 type_init(virtio_register_types)