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