hw/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 "virtio-scsi.h"
  17 #include <hw/scsi.h>
  18 #include <hw/scsi-defs.h>
  19
  20 #define VIRTIO_SCSI_VQ_SIZE     128
  21 #define VIRTIO_SCSI_CDB_SIZE    32
  22 #define VIRTIO_SCSI_SENSE_SIZE  96
  23 #define VIRTIO_SCSI_MAX_CHANNEL 0
  24 #define VIRTIO_SCSI_MAX_TARGET  255
  25 #define VIRTIO_SCSI_MAX_LUN     16383
  26
  27 /* Feature Bits */
  28 #define VIRTIO_SCSI_F_INOUT                    0
  29 #define VIRTIO_SCSI_F_HOTPLUG                  1
  30
  31 /* Response codes */
  32 #define VIRTIO_SCSI_S_OK                       0
  33 #define VIRTIO_SCSI_S_OVERRUN                  1
  34 #define VIRTIO_SCSI_S_ABORTED                  2
  35 #define VIRTIO_SCSI_S_BAD_TARGET               3
  36 #define VIRTIO_SCSI_S_RESET                    4
  37 #define VIRTIO_SCSI_S_BUSY                     5
  38 #define VIRTIO_SCSI_S_TRANSPORT_FAILURE        6
  39 #define VIRTIO_SCSI_S_TARGET_FAILURE           7
  40 #define VIRTIO_SCSI_S_NEXUS_FAILURE            8
  41 #define VIRTIO_SCSI_S_FAILURE                  9
  42 #define VIRTIO_SCSI_S_FUNCTION_SUCCEEDED       10
  43 #define VIRTIO_SCSI_S_FUNCTION_REJECTED        11
  44 #define VIRTIO_SCSI_S_INCORRECT_LUN            12
  45
  46 /* Controlq type codes.  */
  47 #define VIRTIO_SCSI_T_TMF                      0
  48 #define VIRTIO_SCSI_T_AN_QUERY                 1
  49 #define VIRTIO_SCSI_T_AN_SUBSCRIBE             2
  50
  51 /* Valid TMF subtypes.  */
  52 #define VIRTIO_SCSI_T_TMF_ABORT_TASK           0
  53 #define VIRTIO_SCSI_T_TMF_ABORT_TASK_SET       1
  54 #define VIRTIO_SCSI_T_TMF_CLEAR_ACA            2
  55 #define VIRTIO_SCSI_T_TMF_CLEAR_TASK_SET       3
  56 #define VIRTIO_SCSI_T_TMF_I_T_NEXUS_RESET      4
  57 #define VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET   5
  58 #define VIRTIO_SCSI_T_TMF_QUERY_TASK           6
  59 #define VIRTIO_SCSI_T_TMF_QUERY_TASK_SET       7
  60
  61 /* Events.  */
  62 #define VIRTIO_SCSI_T_EVENTS_MISSED            0x80000000
  63 #define VIRTIO_SCSI_T_NO_EVENT                 0
  64 #define VIRTIO_SCSI_T_TRANSPORT_RESET          1
  65 #define VIRTIO_SCSI_T_ASYNC_NOTIFY             2
  66
  67 /* Reasons for transport reset event */
  68 #define VIRTIO_SCSI_EVT_RESET_HARD             0
  69 #define VIRTIO_SCSI_EVT_RESET_RESCAN           1
  70 #define VIRTIO_SCSI_EVT_RESET_REMOVED          2
  71
  72 /* SCSI command request, followed by data-out */
  73 typedef struct {
  74     uint8_t lun[8];              /* Logical Unit Number */
  75     uint64_t tag;                /* Command identifier */
  76     uint8_t task_attr;           /* Task attribute */
  77     uint8_t prio;
  78     uint8_t crn;
  79     uint8_t cdb[];
  80 } QEMU_PACKED VirtIOSCSICmdReq;
  81
  82 /* Response, followed by sense data and data-in */
  83 typedef struct {
  84     uint32_t sense_len;          /* Sense data length */
  85     uint32_t resid;              /* Residual bytes in data buffer */
  86     uint16_t status_qualifier;   /* Status qualifier */
  87     uint8_t status;              /* Command completion status */
  88     uint8_t response;            /* Response values */
  89     uint8_t sense[];
  90 } QEMU_PACKED VirtIOSCSICmdResp;
  91
  92 /* Task Management Request */
  93 typedef struct {
  94     uint32_t type;
  95     uint32_t subtype;
  96     uint8_t lun[8];
  97     uint64_t tag;
  98 } QEMU_PACKED VirtIOSCSICtrlTMFReq;
  99
 100 typedef struct {
 101     uint8_t response;
 102 } QEMU_PACKED VirtIOSCSICtrlTMFResp;
 103
 104 /* Asynchronous notification query/subscription */
 105 typedef struct {
 106     uint32_t type;
 107     uint8_t lun[8];
 108     uint32_t event_requested;
 109 } QEMU_PACKED VirtIOSCSICtrlANReq;
 110
 111 typedef struct {
 112     uint32_t event_actual;
 113     uint8_t response;
 114 } QEMU_PACKED VirtIOSCSICtrlANResp;
 115
 116 typedef struct {
 117     uint32_t event;
 118     uint8_t lun[8];
 119     uint32_t reason;
 120 } QEMU_PACKED VirtIOSCSIEvent;
 121
 122 typedef struct {
 123     uint32_t num_queues;
 124     uint32_t seg_max;
 125     uint32_t max_sectors;
 126     uint32_t cmd_per_lun;
 127     uint32_t event_info_size;
 128     uint32_t sense_size;
 129     uint32_t cdb_size;
 130     uint16_t max_channel;
 131     uint16_t max_target;
 132     uint32_t max_lun;
 133 } QEMU_PACKED VirtIOSCSIConfig;
 134
 135 typedef struct {
 136     VirtIODevice vdev;
 137     DeviceState *qdev;
 138     VirtIOSCSIConf *conf;
 139
 140     SCSIBus bus;
 141     uint32_t sense_size;
 142     uint32_t cdb_size;
 143     int resetting;
 144     VirtQueue *ctrl_vq;
 145     VirtQueue *event_vq;
 146     VirtQueue *cmd_vqs[0];
 147 } VirtIOSCSI;
 148
 149 typedef struct VirtIOSCSIReq {
 150     VirtIOSCSI *dev;
 151     VirtQueue *vq;
 152     VirtQueueElement elem;
 153     QEMUSGList qsgl;
 154     SCSIRequest *sreq;
 155     union {
 156         char                  *buf;
 157         VirtIOSCSICmdReq      *cmd;
 158         VirtIOSCSICtrlTMFReq  *tmf;
 159         VirtIOSCSICtrlANReq   *an;
 160     } req;
 161     union {
 162         char                  *buf;
 163         VirtIOSCSICmdResp     *cmd;
 164         VirtIOSCSICtrlTMFResp *tmf;
 165         VirtIOSCSICtrlANResp  *an;
 166         VirtIOSCSIEvent       *event;
 167     } resp;
 168 } VirtIOSCSIReq;
 169
 170 static inline int virtio_scsi_get_lun(uint8_t *lun)
 171 {
 172     return ((lun[2] << 8) | lun[3]) & 0x3FFF;
 173 }
 174
 175 static inline SCSIDevice *virtio_scsi_device_find(VirtIOSCSI *s, uint8_t *lun)
 176 {
 177     if (lun[0] != 1) {
 178         return NULL;
 179     }
 180     if (lun[2] != 0 && !(lun[2] >= 0x40 && lun[2] < 0x80)) {
 181         return NULL;
 182     }
 183     return scsi_device_find(&s->bus, 0, lun[1], virtio_scsi_get_lun(lun));
 184 }
 185
 186 static void virtio_scsi_complete_req(VirtIOSCSIReq *req)
 187 {
 188     VirtIOSCSI *s = req->dev;
 189     VirtQueue *vq = req->vq;
 190     virtqueue_push(vq, &req->elem, req->qsgl.size + req->elem.in_sg[0].iov_len);
 191     qemu_sglist_destroy(&req->qsgl);
 192     if (req->sreq) {
 193         req->sreq->hba_private = NULL;
 194         scsi_req_unref(req->sreq);
 195     }
 196     g_free(req);
 197     virtio_notify(&s->vdev, vq);
 198 }
 199
 200 static void virtio_scsi_bad_req(void)
 201 {
 202     error_report("wrong size for virtio-scsi headers");
 203     exit(1);
 204 }
 205
 206 static void qemu_sgl_init_external(QEMUSGList *qsgl, struct iovec *sg,
 207                                    target_phys_addr_t *addr, int num)
 208 {
 209     memset(qsgl, 0, sizeof(*qsgl));
 210     while (num--) {
 211         qemu_sglist_add(qsgl, *(addr++), (sg++)->iov_len);
 212     }
 213 }
 214
 215 static void virtio_scsi_parse_req(VirtIOSCSI *s, VirtQueue *vq,
 216                                   VirtIOSCSIReq *req)
 217 {
 218     assert(req->elem.in_num);
 219     req->vq = vq;
 220     req->dev = s;
 221     req->sreq = NULL;
 222     if (req->elem.out_num) {
 223         req->req.buf = req->elem.out_sg[0].iov_base;
 224     }
 225     req->resp.buf = req->elem.in_sg[0].iov_base;
 226
 227     if (req->elem.out_num > 1) {
 228         qemu_sgl_init_external(&req->qsgl, &req->elem.out_sg[1],
 229                                &req->elem.out_addr[1],
 230                                req->elem.out_num - 1);
 231     } else {
 232         qemu_sgl_init_external(&req->qsgl, &req->elem.in_sg[1],
 233                                &req->elem.in_addr[1],
 234                                req->elem.in_num - 1);
 235     }
 236 }
 237
 238 static VirtIOSCSIReq *virtio_scsi_pop_req(VirtIOSCSI *s, VirtQueue *vq)
 239 {
 240     VirtIOSCSIReq *req;
 241     req = g_malloc(sizeof(*req));
 242     if (!virtqueue_pop(vq, &req->elem)) {
 243         g_free(req);
 244         return NULL;
 245     }
 246
 247     virtio_scsi_parse_req(s, vq, req);
 248     return req;
 249 }
 250
 251 static void virtio_scsi_save_request(QEMUFile *f, SCSIRequest *sreq)
 252 {
 253     VirtIOSCSIReq *req = sreq->hba_private;
 254     uint32_t n = virtio_queue_get_id(req->vq) - 2;
 255
 256     assert(n < req->dev->conf->num_queues);
 257     qemu_put_be32s(f, &n);
 258     qemu_put_buffer(f, (unsigned char *)&req->elem, sizeof(req->elem));
 259 }
 260
 261 static void *virtio_scsi_load_request(QEMUFile *f, SCSIRequest *sreq)
 262 {
 263     SCSIBus *bus = sreq->bus;
 264     VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus);
 265     VirtIOSCSIReq *req;
 266     uint32_t n;
 267
 268     req = g_malloc(sizeof(*req));
 269     qemu_get_be32s(f, &n);
 270     assert(n < s->conf->num_queues);
 271     qemu_get_buffer(f, (unsigned char *)&req->elem, sizeof(req->elem));
 272     virtio_scsi_parse_req(s, s->cmd_vqs[n], req);
 273
 274     scsi_req_ref(sreq);
 275     req->sreq = sreq;
 276     if (req->sreq->cmd.mode != SCSI_XFER_NONE) {
 277         int req_mode =
 278             (req->elem.in_num > 1 ? SCSI_XFER_FROM_DEV : SCSI_XFER_TO_DEV);
 279
 280         assert(req->sreq->cmd.mode == req_mode);
 281     }
 282     return req;
 283 }
 284
 285 static void virtio_scsi_do_tmf(VirtIOSCSI *s, VirtIOSCSIReq *req)
 286 {
 287     SCSIDevice *d = virtio_scsi_device_find(s, req->req.tmf->lun);
 288     SCSIRequest *r, *next;
 289     BusChild *kid;
 290     int target;
 291
 292     /* Here VIRTIO_SCSI_S_OK means "FUNCTION COMPLETE".  */
 293     req->resp.tmf->response = VIRTIO_SCSI_S_OK;
 294
 295     switch (req->req.tmf->subtype) {
 296     case VIRTIO_SCSI_T_TMF_ABORT_TASK:
 297     case VIRTIO_SCSI_T_TMF_QUERY_TASK:
 298         if (!d) {
 299             goto fail;
 300         }
 301         if (d->lun != virtio_scsi_get_lun(req->req.tmf->lun)) {
 302             goto incorrect_lun;
 303         }
 304         QTAILQ_FOREACH_SAFE(r, &d->requests, next, next) {
 305             if (r->tag == req->req.tmf->tag) {
 306                 break;
 307             }
 308         }
 309         if (r && r->hba_private) {
 310             if (req->req.tmf->subtype == VIRTIO_SCSI_T_TMF_QUERY_TASK) {
 311                 /* "If the specified command is present in the task set, then
 312                  * return a service response set to FUNCTION SUCCEEDED".
 313                  */
 314                 req->resp.tmf->response = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
 315             } else {
 316                 scsi_req_cancel(r);
 317             }
 318         }
 319         break;
 320
 321     case VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET:
 322         if (!d) {
 323             goto fail;
 324         }
 325         if (d->lun != virtio_scsi_get_lun(req->req.tmf->lun)) {
 326             goto incorrect_lun;
 327         }
 328         s->resetting++;
 329         qdev_reset_all(&d->qdev);
 330         s->resetting--;
 331         break;
 332
 333     case VIRTIO_SCSI_T_TMF_ABORT_TASK_SET:
 334     case VIRTIO_SCSI_T_TMF_CLEAR_TASK_SET:
 335     case VIRTIO_SCSI_T_TMF_QUERY_TASK_SET:
 336         if (!d) {
 337             goto fail;
 338         }
 339         if (d->lun != virtio_scsi_get_lun(req->req.tmf->lun)) {
 340             goto incorrect_lun;
 341         }
 342         QTAILQ_FOREACH_SAFE(r, &d->requests, next, next) {
 343             if (r->hba_private) {
 344                 if (req->req.tmf->subtype == VIRTIO_SCSI_T_TMF_QUERY_TASK_SET) {
 345                     /* "If there is any command present in the task set, then
 346                      * return a service response set to FUNCTION SUCCEEDED".
 347                      */
 348                     req->resp.tmf->response = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
 349                     break;
 350                 } else {
 351                     scsi_req_cancel(r);
 352                 }
 353             }
 354         }
 355         break;
 356
 357     case VIRTIO_SCSI_T_TMF_I_T_NEXUS_RESET:
 358         target = req->req.tmf->lun[1];
 359         s->resetting++;
 360         QTAILQ_FOREACH(kid, &s->bus.qbus.children, sibling) {
 361              d = DO_UPCAST(SCSIDevice, qdev, kid->child);
 362              if (d->channel == 0 && d->id == target) {
 363                 qdev_reset_all(&d->qdev);
 364              }
 365         }
 366         s->resetting--;
 367         break;
 368
 369     case VIRTIO_SCSI_T_TMF_CLEAR_ACA:
 370     default:
 371         req->resp.tmf->response = VIRTIO_SCSI_S_FUNCTION_REJECTED;
 372         break;
 373     }
 374
 375     return;
 376
 377 incorrect_lun:
 378     req->resp.tmf->response = VIRTIO_SCSI_S_INCORRECT_LUN;
 379     return;
 380
 381 fail:
 382     req->resp.tmf->response = VIRTIO_SCSI_S_BAD_TARGET;
 383 }
 384
 385 static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
 386 {
 387     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 388     VirtIOSCSIReq *req;
 389
 390     while ((req = virtio_scsi_pop_req(s, vq))) {
 391         int out_size, in_size;
 392         if (req->elem.out_num < 1 || req->elem.in_num < 1) {
 393             virtio_scsi_bad_req();
 394             continue;
 395         }
 396
 397         out_size = req->elem.out_sg[0].iov_len;
 398         in_size = req->elem.in_sg[0].iov_len;
 399         if (req->req.tmf->type == VIRTIO_SCSI_T_TMF) {
 400             if (out_size < sizeof(VirtIOSCSICtrlTMFReq) ||
 401                 in_size < sizeof(VirtIOSCSICtrlTMFResp)) {
 402                 virtio_scsi_bad_req();
 403             }
 404             virtio_scsi_do_tmf(s, req);
 405
 406         } else if (req->req.tmf->type == VIRTIO_SCSI_T_AN_QUERY ||
 407                    req->req.tmf->type == VIRTIO_SCSI_T_AN_SUBSCRIBE) {
 408             if (out_size < sizeof(VirtIOSCSICtrlANReq) ||
 409                 in_size < sizeof(VirtIOSCSICtrlANResp)) {
 410                 virtio_scsi_bad_req();
 411             }
 412             req->resp.an->event_actual = 0;
 413             req->resp.an->response = VIRTIO_SCSI_S_OK;
 414         }
 415         virtio_scsi_complete_req(req);
 416     }
 417 }
 418
 419 static void virtio_scsi_handle_event(VirtIODevice *vdev, VirtQueue *vq)
 420 {
 421 }
 422
 423 static void virtio_scsi_command_complete(SCSIRequest *r, uint32_t status,
 424                                          size_t resid)
 425 {
 426     VirtIOSCSIReq *req = r->hba_private;
 427
 428     req->resp.cmd->response = VIRTIO_SCSI_S_OK;
 429     req->resp.cmd->status = status;
 430     if (req->resp.cmd->status == GOOD) {
 431         req->resp.cmd->resid = resid;
 432     } else {
 433         req->resp.cmd->resid = 0;
 434         req->resp.cmd->sense_len =
 435             scsi_req_get_sense(r, req->resp.cmd->sense, VIRTIO_SCSI_SENSE_SIZE);
 436     }
 437     virtio_scsi_complete_req(req);
 438 }
 439
 440 static QEMUSGList *virtio_scsi_get_sg_list(SCSIRequest *r)
 441 {
 442     VirtIOSCSIReq *req = r->hba_private;
 443
 444     return &req->qsgl;
 445 }
 446
 447 static void virtio_scsi_request_cancelled(SCSIRequest *r)
 448 {
 449     VirtIOSCSIReq *req = r->hba_private;
 450
 451     if (!req) {
 452         return;
 453     }
 454     if (req->dev->resetting) {
 455         req->resp.cmd->response = VIRTIO_SCSI_S_RESET;
 456     } else {
 457         req->resp.cmd->response = VIRTIO_SCSI_S_ABORTED;
 458     }
 459     virtio_scsi_complete_req(req);
 460 }
 461
 462 static void virtio_scsi_fail_cmd_req(VirtIOSCSIReq *req)
 463 {
 464     req->resp.cmd->response = VIRTIO_SCSI_S_FAILURE;
 465     virtio_scsi_complete_req(req);
 466 }
 467
 468 static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
 469 {
 470     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 471     VirtIOSCSIReq *req;
 472     int n;
 473
 474     while ((req = virtio_scsi_pop_req(s, vq))) {
 475         SCSIDevice *d;
 476         int out_size, in_size;
 477         if (req->elem.out_num < 1 || req->elem.in_num < 1) {
 478             virtio_scsi_bad_req();
 479         }
 480
 481         out_size = req->elem.out_sg[0].iov_len;
 482         in_size = req->elem.in_sg[0].iov_len;
 483         if (out_size < sizeof(VirtIOSCSICmdReq) + s->cdb_size ||
 484             in_size < sizeof(VirtIOSCSICmdResp) + s->sense_size) {
 485             virtio_scsi_bad_req();
 486         }
 487
 488         if (req->elem.out_num > 1 && req->elem.in_num > 1) {
 489             virtio_scsi_fail_cmd_req(req);
 490             continue;
 491         }
 492
 493         d = virtio_scsi_device_find(s, req->req.cmd->lun);
 494         if (!d) {
 495             req->resp.cmd->response = VIRTIO_SCSI_S_BAD_TARGET;
 496             virtio_scsi_complete_req(req);
 497             continue;
 498         }
 499         req->sreq = scsi_req_new(d, req->req.cmd->tag,
 500                                  virtio_scsi_get_lun(req->req.cmd->lun),
 501                                  req->req.cmd->cdb, req);
 502
 503         if (req->sreq->cmd.mode != SCSI_XFER_NONE) {
 504             int req_mode =
 505                 (req->elem.in_num > 1 ? SCSI_XFER_FROM_DEV : SCSI_XFER_TO_DEV);
 506
 507             if (req->sreq->cmd.mode != req_mode ||
 508                 req->sreq->cmd.xfer > req->qsgl.size) {
 509                 req->resp.cmd->response = VIRTIO_SCSI_S_OVERRUN;
 510                 virtio_scsi_complete_req(req);
 511                 continue;
 512             }
 513         }
 514
 515         n = scsi_req_enqueue(req->sreq);
 516         if (n) {
 517             scsi_req_continue(req->sreq);
 518         }
 519     }
 520 }
 521
 522 static void virtio_scsi_get_config(VirtIODevice *vdev,
 523                                    uint8_t *config)
 524 {
 525     VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config;
 526     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 527
 528     stl_raw(&scsiconf->num_queues, s->conf->num_queues);
 529     stl_raw(&scsiconf->seg_max, 128 - 2);
 530     stl_raw(&scsiconf->max_sectors, s->conf->max_sectors);
 531     stl_raw(&scsiconf->cmd_per_lun, s->conf->cmd_per_lun);
 532     stl_raw(&scsiconf->event_info_size, sizeof(VirtIOSCSIEvent));
 533     stl_raw(&scsiconf->sense_size, s->sense_size);
 534     stl_raw(&scsiconf->cdb_size, s->cdb_size);
 535     stl_raw(&scsiconf->max_channel, VIRTIO_SCSI_MAX_CHANNEL);
 536     stl_raw(&scsiconf->max_target, VIRTIO_SCSI_MAX_TARGET);
 537     stl_raw(&scsiconf->max_lun, VIRTIO_SCSI_MAX_LUN);
 538 }
 539
 540 static void virtio_scsi_set_config(VirtIODevice *vdev,
 541                                    const uint8_t *config)
 542 {
 543     VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config;
 544     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 545
 546     if ((uint32_t) ldl_raw(&scsiconf->sense_size) >= 65536 ||
 547         (uint32_t) ldl_raw(&scsiconf->cdb_size) >= 256) {
 548         error_report("bad data written to virtio-scsi configuration space");
 549         exit(1);
 550     }
 551
 552     s->sense_size = ldl_raw(&scsiconf->sense_size);
 553     s->cdb_size = ldl_raw(&scsiconf->cdb_size);
 554 }
 555
 556 static uint32_t virtio_scsi_get_features(VirtIODevice *vdev,
 557                                          uint32_t requested_features)
 558 {
 559     requested_features |= (1UL << VIRTIO_SCSI_F_HOTPLUG);
 560     return requested_features;
 561 }
 562
 563 static void virtio_scsi_reset(VirtIODevice *vdev)
 564 {
 565     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 566
 567     s->sense_size = VIRTIO_SCSI_SENSE_SIZE;
 568     s->cdb_size = VIRTIO_SCSI_CDB_SIZE;
 569 }
 570
 571 /* The device does not have anything to save beyond the virtio data.
 572  * Request data is saved with callbacks from SCSI devices.
 573  */
 574 static void virtio_scsi_save(QEMUFile *f, void *opaque)
 575 {
 576     VirtIOSCSI *s = opaque;
 577     virtio_save(&s->vdev, f);
 578 }
 579
 580 static int virtio_scsi_load(QEMUFile *f, void *opaque, int version_id)
 581 {
 582     VirtIOSCSI *s = opaque;
 583     int ret;
 584
 585     ret = virtio_load(&s->vdev, f);
 586     if (ret) {
 587         return ret;
 588     }
 589     return 0;
 590 }
 591
 592 static void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev,
 593                                    uint32_t event, uint32_t reason)
 594 {
 595     VirtIOSCSIReq *req = virtio_scsi_pop_req(s, s->event_vq);
 596     VirtIOSCSIEvent *evt;
 597
 598     if (req) {
 599         int in_size;
 600         if (req->elem.out_num || req->elem.in_num != 1) {
 601             virtio_scsi_bad_req();
 602         }
 603
 604         in_size = req->elem.in_sg[0].iov_len;
 605         if (in_size < sizeof(VirtIOSCSIEvent)) {
 606             virtio_scsi_bad_req();
 607         }
 608
 609         evt = req->resp.event;
 610         memset(evt, 0, sizeof(VirtIOSCSIEvent));
 611         evt->event = event;
 612         evt->reason = reason;
 613         evt->lun[0] = 1;
 614         evt->lun[1] = dev->id;
 615
 616         /* Linux wants us to keep the same encoding we use for REPORT LUNS.  */
 617         if (dev->lun >= 256) {
 618             evt->lun[2] = (dev->lun >> 8) | 0x40;
 619         }
 620         evt->lun[3] = dev->lun & 0xFF;
 621         virtio_scsi_complete_req(req);
 622     }
 623 }
 624
 625 static void virtio_scsi_hotplug(SCSIBus *bus, SCSIDevice *dev)
 626 {
 627     VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus);
 628
 629     if (((s->vdev.guest_features >> VIRTIO_SCSI_F_HOTPLUG) & 1) &&
 630         (s->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK)) {
 631         virtio_scsi_push_event(s, dev, VIRTIO_SCSI_T_TRANSPORT_RESET,
 632                                VIRTIO_SCSI_EVT_RESET_RESCAN);
 633     }
 634 }
 635
 636 static void virtio_scsi_hot_unplug(SCSIBus *bus, SCSIDevice *dev)
 637 {
 638     VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus);
 639
 640     if ((s->vdev.guest_features >> VIRTIO_SCSI_F_HOTPLUG) & 1) {
 641         virtio_scsi_push_event(s, dev, VIRTIO_SCSI_T_TRANSPORT_RESET,
 642                                VIRTIO_SCSI_EVT_RESET_REMOVED);
 643     }
 644 }
 645
 646 static struct SCSIBusInfo virtio_scsi_scsi_info = {
 647     .tcq = true,
 648     .max_channel = VIRTIO_SCSI_MAX_CHANNEL,
 649     .max_target = VIRTIO_SCSI_MAX_TARGET,
 650     .max_lun = VIRTIO_SCSI_MAX_LUN,
 651
 652     .complete = virtio_scsi_command_complete,
 653     .cancel = virtio_scsi_request_cancelled,
 654     .hotplug = virtio_scsi_hotplug,
 655     .hot_unplug = virtio_scsi_hot_unplug,
 656     .get_sg_list = virtio_scsi_get_sg_list,
 657     .save_request = virtio_scsi_save_request,
 658     .load_request = virtio_scsi_load_request,
 659 };
 660
 661 VirtIODevice *virtio_scsi_init(DeviceState *dev, VirtIOSCSIConf *proxyconf)
 662 {
 663     VirtIOSCSI *s;
 664     static int virtio_scsi_id;
 665     size_t sz;
 666     int i;
 667
 668     sz = sizeof(VirtIOSCSI) + proxyconf->num_queues * sizeof(VirtQueue *);
 669     s = (VirtIOSCSI *)virtio_common_init("virtio-scsi", VIRTIO_ID_SCSI,
 670                                          sizeof(VirtIOSCSIConfig), sz);
 671
 672     s->qdev = dev;
 673     s->conf = proxyconf;
 674
 675     /* TODO set up vdev function pointers */
 676     s->vdev.get_config = virtio_scsi_get_config;
 677     s->vdev.set_config = virtio_scsi_set_config;
 678     s->vdev.get_features = virtio_scsi_get_features;
 679     s->vdev.reset = virtio_scsi_reset;
 680
 681     s->ctrl_vq = virtio_add_queue(&s->vdev, VIRTIO_SCSI_VQ_SIZE,
 682                                    virtio_scsi_handle_ctrl);
 683     s->event_vq = virtio_add_queue(&s->vdev, VIRTIO_SCSI_VQ_SIZE,
 684                                    virtio_scsi_handle_event);
 685     for (i = 0; i < s->conf->num_queues; i++) {
 686         s->cmd_vqs[i] = virtio_add_queue(&s->vdev, VIRTIO_SCSI_VQ_SIZE,
 687                                          virtio_scsi_handle_cmd);
 688     }
 689
 690     scsi_bus_new(&s->bus, dev, &virtio_scsi_scsi_info);
 691     if (!dev->hotplugged) {
 692         scsi_bus_legacy_handle_cmdline(&s->bus);
 693     }
 694
 695     register_savevm(dev, "virtio-scsi", virtio_scsi_id++, 1,
 696                     virtio_scsi_save, virtio_scsi_load, s);
 697
 698     return &s->vdev;
 699 }
 700
 701 void virtio_scsi_exit(VirtIODevice *vdev)
 702 {
 703     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 704     unregister_savevm(s->qdev, "virtio-scsi", s);
 705     virtio_cleanup(vdev);
 706 }