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 "hw/virtio-scsi.h"
  17 #include "qemu/error-report.h"
  18 #include <hw/scsi.h>
  19 #include <hw/scsi-defs.h>
  20 #include "hw/virtio-bus.h"
  21
  22 #define VIRTIO_SCSI_VQ_SIZE     128
  23 #define VIRTIO_SCSI_CDB_SIZE    32
  24 #define VIRTIO_SCSI_SENSE_SIZE  96
  25 #define VIRTIO_SCSI_MAX_CHANNEL 0
  26 #define VIRTIO_SCSI_MAX_TARGET  255
  27 #define VIRTIO_SCSI_MAX_LUN     16383
  28
  29 /* Response codes */
  30 #define VIRTIO_SCSI_S_OK                       0
  31 #define VIRTIO_SCSI_S_OVERRUN                  1
  32 #define VIRTIO_SCSI_S_ABORTED                  2
  33 #define VIRTIO_SCSI_S_BAD_TARGET               3
  34 #define VIRTIO_SCSI_S_RESET                    4
  35 #define VIRTIO_SCSI_S_BUSY                     5
  36 #define VIRTIO_SCSI_S_TRANSPORT_FAILURE        6
  37 #define VIRTIO_SCSI_S_TARGET_FAILURE           7
  38 #define VIRTIO_SCSI_S_NEXUS_FAILURE            8
  39 #define VIRTIO_SCSI_S_FAILURE                  9
  40 #define VIRTIO_SCSI_S_FUNCTION_SUCCEEDED       10
  41 #define VIRTIO_SCSI_S_FUNCTION_REJECTED        11
  42 #define VIRTIO_SCSI_S_INCORRECT_LUN            12
  43
  44 /* Controlq type codes.  */
  45 #define VIRTIO_SCSI_T_TMF                      0
  46 #define VIRTIO_SCSI_T_AN_QUERY                 1
  47 #define VIRTIO_SCSI_T_AN_SUBSCRIBE             2
  48
  49 /* Valid TMF subtypes.  */
  50 #define VIRTIO_SCSI_T_TMF_ABORT_TASK           0
  51 #define VIRTIO_SCSI_T_TMF_ABORT_TASK_SET       1
  52 #define VIRTIO_SCSI_T_TMF_CLEAR_ACA            2
  53 #define VIRTIO_SCSI_T_TMF_CLEAR_TASK_SET       3
  54 #define VIRTIO_SCSI_T_TMF_I_T_NEXUS_RESET      4
  55 #define VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET   5
  56 #define VIRTIO_SCSI_T_TMF_QUERY_TASK           6
  57 #define VIRTIO_SCSI_T_TMF_QUERY_TASK_SET       7
  58
  59 /* Events.  */
  60 #define VIRTIO_SCSI_T_EVENTS_MISSED            0x80000000
  61 #define VIRTIO_SCSI_T_NO_EVENT                 0
  62 #define VIRTIO_SCSI_T_TRANSPORT_RESET          1
  63 #define VIRTIO_SCSI_T_ASYNC_NOTIFY             2
  64 #define VIRTIO_SCSI_T_PARAM_CHANGE             3
  65
  66 /* Reasons for transport reset event */
  67 #define VIRTIO_SCSI_EVT_RESET_HARD             0
  68 #define VIRTIO_SCSI_EVT_RESET_RESCAN           1
  69 #define VIRTIO_SCSI_EVT_RESET_REMOVED          2
  70
  71 /* SCSI command request, followed by data-out */
  72 typedef struct {
  73     uint8_t lun[8];              /* Logical Unit Number */
  74     uint64_t tag;                /* Command identifier */
  75     uint8_t task_attr;           /* Task attribute */
  76     uint8_t prio;
  77     uint8_t crn;
  78     uint8_t cdb[];
  79 } QEMU_PACKED VirtIOSCSICmdReq;
  80
  81 /* Response, followed by sense data and data-in */
  82 typedef struct {
  83     uint32_t sense_len;          /* Sense data length */
  84     uint32_t resid;              /* Residual bytes in data buffer */
  85     uint16_t status_qualifier;   /* Status qualifier */
  86     uint8_t status;              /* Command completion status */
  87     uint8_t response;            /* Response values */
  88     uint8_t sense[];
  89 } QEMU_PACKED VirtIOSCSICmdResp;
  90
  91 /* Task Management Request */
  92 typedef struct {
  93     uint32_t type;
  94     uint32_t subtype;
  95     uint8_t lun[8];
  96     uint64_t tag;
  97 } QEMU_PACKED VirtIOSCSICtrlTMFReq;
  98
  99 typedef struct {
 100     uint8_t response;
 101 } QEMU_PACKED VirtIOSCSICtrlTMFResp;
 102
 103 /* Asynchronous notification query/subscription */
 104 typedef struct {
 105     uint32_t type;
 106     uint8_t lun[8];
 107     uint32_t event_requested;
 108 } QEMU_PACKED VirtIOSCSICtrlANReq;
 109
 110 typedef struct {
 111     uint32_t event_actual;
 112     uint8_t response;
 113 } QEMU_PACKED VirtIOSCSICtrlANResp;
 114
 115 typedef struct {
 116     uint32_t event;
 117     uint8_t lun[8];
 118     uint32_t reason;
 119 } QEMU_PACKED VirtIOSCSIEvent;
 120
 121 typedef struct {
 122     uint32_t num_queues;
 123     uint32_t seg_max;
 124     uint32_t max_sectors;
 125     uint32_t cmd_per_lun;
 126     uint32_t event_info_size;
 127     uint32_t sense_size;
 128     uint32_t cdb_size;
 129     uint16_t max_channel;
 130     uint16_t max_target;
 131     uint32_t max_lun;
 132 } QEMU_PACKED VirtIOSCSIConfig;
 133
 134 typedef struct VirtIOSCSIReq {
 135     VirtIOSCSI *dev;
 136     VirtQueue *vq;
 137     VirtQueueElement elem;
 138     QEMUSGList qsgl;
 139     SCSIRequest *sreq;
 140     union {
 141         char                  *buf;
 142         VirtIOSCSICmdReq      *cmd;
 143         VirtIOSCSICtrlTMFReq  *tmf;
 144         VirtIOSCSICtrlANReq   *an;
 145     } req;
 146     union {
 147         char                  *buf;
 148         VirtIOSCSICmdResp     *cmd;
 149         VirtIOSCSICtrlTMFResp *tmf;
 150         VirtIOSCSICtrlANResp  *an;
 151         VirtIOSCSIEvent       *event;
 152     } resp;
 153 } VirtIOSCSIReq;
 154
 155 static inline int virtio_scsi_get_lun(uint8_t *lun)
 156 {
 157     return ((lun[2] << 8) | lun[3]) & 0x3FFF;
 158 }
 159
 160 static inline SCSIDevice *virtio_scsi_device_find(VirtIOSCSI *s, uint8_t *lun)
 161 {
 162     if (lun[0] != 1) {
 163         return NULL;
 164     }
 165     if (lun[2] != 0 && !(lun[2] >= 0x40 && lun[2] < 0x80)) {
 166         return NULL;
 167     }
 168     return scsi_device_find(&s->bus, 0, lun[1], virtio_scsi_get_lun(lun));
 169 }
 170
 171 static void virtio_scsi_complete_req(VirtIOSCSIReq *req)
 172 {
 173     VirtIOSCSI *s = req->dev;
 174     VirtQueue *vq = req->vq;
 175     VirtIODevice *vdev = VIRTIO_DEVICE(s);
 176     virtqueue_push(vq, &req->elem, req->qsgl.size + req->elem.in_sg[0].iov_len);
 177     qemu_sglist_destroy(&req->qsgl);
 178     if (req->sreq) {
 179         req->sreq->hba_private = NULL;
 180         scsi_req_unref(req->sreq);
 181     }
 182     g_free(req);
 183     virtio_notify(vdev, vq);
 184 }
 185
 186 static void virtio_scsi_bad_req(void)
 187 {
 188     error_report("wrong size for virtio-scsi headers");
 189     exit(1);
 190 }
 191
 192 static void qemu_sgl_init_external(QEMUSGList *qsgl, struct iovec *sg,
 193                                    hwaddr *addr, int num)
 194 {
 195     qemu_sglist_init(qsgl, num, &dma_context_memory);
 196     while (num--) {
 197         qemu_sglist_add(qsgl, *(addr++), (sg++)->iov_len);
 198     }
 199 }
 200
 201 static void virtio_scsi_parse_req(VirtIOSCSI *s, VirtQueue *vq,
 202                                   VirtIOSCSIReq *req)
 203 {
 204     assert(req->elem.in_num);
 205     req->vq = vq;
 206     req->dev = s;
 207     req->sreq = NULL;
 208     if (req->elem.out_num) {
 209         req->req.buf = req->elem.out_sg[0].iov_base;
 210     }
 211     req->resp.buf = req->elem.in_sg[0].iov_base;
 212
 213     if (req->elem.out_num > 1) {
 214         qemu_sgl_init_external(&req->qsgl, &req->elem.out_sg[1],
 215                                &req->elem.out_addr[1],
 216                                req->elem.out_num - 1);
 217     } else {
 218         qemu_sgl_init_external(&req->qsgl, &req->elem.in_sg[1],
 219                                &req->elem.in_addr[1],
 220                                req->elem.in_num - 1);
 221     }
 222 }
 223
 224 static VirtIOSCSIReq *virtio_scsi_pop_req(VirtIOSCSI *s, VirtQueue *vq)
 225 {
 226     VirtIOSCSIReq *req;
 227     req = g_malloc(sizeof(*req));
 228     if (!virtqueue_pop(vq, &req->elem)) {
 229         g_free(req);
 230         return NULL;
 231     }
 232
 233     virtio_scsi_parse_req(s, vq, req);
 234     return req;
 235 }
 236
 237 static void virtio_scsi_save_request(QEMUFile *f, SCSIRequest *sreq)
 238 {
 239     VirtIOSCSIReq *req = sreq->hba_private;
 240     uint32_t n = virtio_queue_get_id(req->vq) - 2;
 241
 242     assert(n < req->dev->conf.num_queues);
 243     qemu_put_be32s(f, &n);
 244     qemu_put_buffer(f, (unsigned char *)&req->elem, sizeof(req->elem));
 245 }
 246
 247 static void *virtio_scsi_load_request(QEMUFile *f, SCSIRequest *sreq)
 248 {
 249     SCSIBus *bus = sreq->bus;
 250     VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus);
 251     VirtIOSCSIReq *req;
 252     uint32_t n;
 253
 254     req = g_malloc(sizeof(*req));
 255     qemu_get_be32s(f, &n);
 256     assert(n < s->conf.num_queues);
 257     qemu_get_buffer(f, (unsigned char *)&req->elem, sizeof(req->elem));
 258     virtio_scsi_parse_req(s, s->cmd_vqs[n], req);
 259
 260     scsi_req_ref(sreq);
 261     req->sreq = sreq;
 262     if (req->sreq->cmd.mode != SCSI_XFER_NONE) {
 263         int req_mode =
 264             (req->elem.in_num > 1 ? SCSI_XFER_FROM_DEV : SCSI_XFER_TO_DEV);
 265
 266         assert(req->sreq->cmd.mode == req_mode);
 267     }
 268     return req;
 269 }
 270
 271 static void virtio_scsi_do_tmf(VirtIOSCSI *s, VirtIOSCSIReq *req)
 272 {
 273     SCSIDevice *d = virtio_scsi_device_find(s, req->req.tmf->lun);
 274     SCSIRequest *r, *next;
 275     BusChild *kid;
 276     int target;
 277
 278     /* Here VIRTIO_SCSI_S_OK means "FUNCTION COMPLETE".  */
 279     req->resp.tmf->response = VIRTIO_SCSI_S_OK;
 280
 281     switch (req->req.tmf->subtype) {
 282     case VIRTIO_SCSI_T_TMF_ABORT_TASK:
 283     case VIRTIO_SCSI_T_TMF_QUERY_TASK:
 284         if (!d) {
 285             goto fail;
 286         }
 287         if (d->lun != virtio_scsi_get_lun(req->req.tmf->lun)) {
 288             goto incorrect_lun;
 289         }
 290         QTAILQ_FOREACH_SAFE(r, &d->requests, next, next) {
 291             VirtIOSCSIReq *cmd_req = r->hba_private;
 292             if (cmd_req && cmd_req->req.cmd->tag == req->req.tmf->tag) {
 293                 break;
 294             }
 295         }
 296         if (r) {
 297             /*
 298              * Assert that the request has not been completed yet, we
 299              * check for it in the loop above.
 300              */
 301             assert(r->hba_private);
 302             if (req->req.tmf->subtype == VIRTIO_SCSI_T_TMF_QUERY_TASK) {
 303                 /* "If the specified command is present in the task set, then
 304                  * return a service response set to FUNCTION SUCCEEDED".
 305                  */
 306                 req->resp.tmf->response = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
 307             } else {
 308                 scsi_req_cancel(r);
 309             }
 310         }
 311         break;
 312
 313     case VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET:
 314         if (!d) {
 315             goto fail;
 316         }
 317         if (d->lun != virtio_scsi_get_lun(req->req.tmf->lun)) {
 318             goto incorrect_lun;
 319         }
 320         s->resetting++;
 321         qdev_reset_all(&d->qdev);
 322         s->resetting--;
 323         break;
 324
 325     case VIRTIO_SCSI_T_TMF_ABORT_TASK_SET:
 326     case VIRTIO_SCSI_T_TMF_CLEAR_TASK_SET:
 327     case VIRTIO_SCSI_T_TMF_QUERY_TASK_SET:
 328         if (!d) {
 329             goto fail;
 330         }
 331         if (d->lun != virtio_scsi_get_lun(req->req.tmf->lun)) {
 332             goto incorrect_lun;
 333         }
 334         QTAILQ_FOREACH_SAFE(r, &d->requests, next, next) {
 335             if (r->hba_private) {
 336                 if (req->req.tmf->subtype == VIRTIO_SCSI_T_TMF_QUERY_TASK_SET) {
 337                     /* "If there is any command present in the task set, then
 338                      * return a service response set to FUNCTION SUCCEEDED".
 339                      */
 340                     req->resp.tmf->response = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
 341                     break;
 342                 } else {
 343                     scsi_req_cancel(r);
 344                 }
 345             }
 346         }
 347         break;
 348
 349     case VIRTIO_SCSI_T_TMF_I_T_NEXUS_RESET:
 350         target = req->req.tmf->lun[1];
 351         s->resetting++;
 352         QTAILQ_FOREACH(kid, &s->bus.qbus.children, sibling) {
 353              d = DO_UPCAST(SCSIDevice, qdev, kid->child);
 354              if (d->channel == 0 && d->id == target) {
 355                 qdev_reset_all(&d->qdev);
 356              }
 357         }
 358         s->resetting--;
 359         break;
 360
 361     case VIRTIO_SCSI_T_TMF_CLEAR_ACA:
 362     default:
 363         req->resp.tmf->response = VIRTIO_SCSI_S_FUNCTION_REJECTED;
 364         break;
 365     }
 366
 367     return;
 368
 369 incorrect_lun:
 370     req->resp.tmf->response = VIRTIO_SCSI_S_INCORRECT_LUN;
 371     return;
 372
 373 fail:
 374     req->resp.tmf->response = VIRTIO_SCSI_S_BAD_TARGET;
 375 }
 376
 377 static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
 378 {
 379     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 380     VirtIOSCSIReq *req;
 381
 382     while ((req = virtio_scsi_pop_req(s, vq))) {
 383         int out_size, in_size;
 384         if (req->elem.out_num < 1 || req->elem.in_num < 1) {
 385             virtio_scsi_bad_req();
 386             continue;
 387         }
 388
 389         out_size = req->elem.out_sg[0].iov_len;
 390         in_size = req->elem.in_sg[0].iov_len;
 391         if (req->req.tmf->type == VIRTIO_SCSI_T_TMF) {
 392             if (out_size < sizeof(VirtIOSCSICtrlTMFReq) ||
 393                 in_size < sizeof(VirtIOSCSICtrlTMFResp)) {
 394                 virtio_scsi_bad_req();
 395             }
 396             virtio_scsi_do_tmf(s, req);
 397
 398         } else if (req->req.tmf->type == VIRTIO_SCSI_T_AN_QUERY ||
 399                    req->req.tmf->type == VIRTIO_SCSI_T_AN_SUBSCRIBE) {
 400             if (out_size < sizeof(VirtIOSCSICtrlANReq) ||
 401                 in_size < sizeof(VirtIOSCSICtrlANResp)) {
 402                 virtio_scsi_bad_req();
 403             }
 404             req->resp.an->event_actual = 0;
 405             req->resp.an->response = VIRTIO_SCSI_S_OK;
 406         }
 407         virtio_scsi_complete_req(req);
 408     }
 409 }
 410
 411 static void virtio_scsi_command_complete(SCSIRequest *r, uint32_t status,
 412                                          size_t resid)
 413 {
 414     VirtIOSCSIReq *req = r->hba_private;
 415     uint32_t sense_len;
 416
 417     req->resp.cmd->response = VIRTIO_SCSI_S_OK;
 418     req->resp.cmd->status = status;
 419     if (req->resp.cmd->status == GOOD) {
 420         req->resp.cmd->resid = tswap32(resid);
 421     } else {
 422         req->resp.cmd->resid = 0;
 423         sense_len = scsi_req_get_sense(r, req->resp.cmd->sense,
 424                                        VIRTIO_SCSI_SENSE_SIZE);
 425         req->resp.cmd->sense_len = tswap32(sense_len);
 426     }
 427     virtio_scsi_complete_req(req);
 428 }
 429
 430 static QEMUSGList *virtio_scsi_get_sg_list(SCSIRequest *r)
 431 {
 432     VirtIOSCSIReq *req = r->hba_private;
 433
 434     return &req->qsgl;
 435 }
 436
 437 static void virtio_scsi_request_cancelled(SCSIRequest *r)
 438 {
 439     VirtIOSCSIReq *req = r->hba_private;
 440
 441     if (!req) {
 442         return;
 443     }
 444     if (req->dev->resetting) {
 445         req->resp.cmd->response = VIRTIO_SCSI_S_RESET;
 446     } else {
 447         req->resp.cmd->response = VIRTIO_SCSI_S_ABORTED;
 448     }
 449     virtio_scsi_complete_req(req);
 450 }
 451
 452 static void virtio_scsi_fail_cmd_req(VirtIOSCSIReq *req)
 453 {
 454     req->resp.cmd->response = VIRTIO_SCSI_S_FAILURE;
 455     virtio_scsi_complete_req(req);
 456 }
 457
 458 static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
 459 {
 460     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 461     VirtIOSCSIReq *req;
 462     int n;
 463
 464     while ((req = virtio_scsi_pop_req(s, vq))) {
 465         SCSIDevice *d;
 466         int out_size, in_size;
 467         if (req->elem.out_num < 1 || req->elem.in_num < 1) {
 468             virtio_scsi_bad_req();
 469         }
 470
 471         out_size = req->elem.out_sg[0].iov_len;
 472         in_size = req->elem.in_sg[0].iov_len;
 473         if (out_size < sizeof(VirtIOSCSICmdReq) + s->cdb_size ||
 474             in_size < sizeof(VirtIOSCSICmdResp) + s->sense_size) {
 475             virtio_scsi_bad_req();
 476         }
 477
 478         if (req->elem.out_num > 1 && req->elem.in_num > 1) {
 479             virtio_scsi_fail_cmd_req(req);
 480             continue;
 481         }
 482
 483         d = virtio_scsi_device_find(s, req->req.cmd->lun);
 484         if (!d) {
 485             req->resp.cmd->response = VIRTIO_SCSI_S_BAD_TARGET;
 486             virtio_scsi_complete_req(req);
 487             continue;
 488         }
 489         req->sreq = scsi_req_new(d, req->req.cmd->tag,
 490                                  virtio_scsi_get_lun(req->req.cmd->lun),
 491                                  req->req.cmd->cdb, req);
 492
 493         if (req->sreq->cmd.mode != SCSI_XFER_NONE) {
 494             int req_mode =
 495                 (req->elem.in_num > 1 ? SCSI_XFER_FROM_DEV : SCSI_XFER_TO_DEV);
 496
 497             if (req->sreq->cmd.mode != req_mode ||
 498                 req->sreq->cmd.xfer > req->qsgl.size) {
 499                 req->resp.cmd->response = VIRTIO_SCSI_S_OVERRUN;
 500                 virtio_scsi_complete_req(req);
 501                 continue;
 502             }
 503         }
 504
 505         n = scsi_req_enqueue(req->sreq);
 506         if (n) {
 507             scsi_req_continue(req->sreq);
 508         }
 509     }
 510 }
 511
 512 static void virtio_scsi_get_config(VirtIODevice *vdev,
 513                                    uint8_t *config)
 514 {
 515     VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config;
 516     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 517
 518     stl_raw(&scsiconf->num_queues, s->conf.num_queues);
 519     stl_raw(&scsiconf->seg_max, 128 - 2);
 520     stl_raw(&scsiconf->max_sectors, s->conf.max_sectors);
 521     stl_raw(&scsiconf->cmd_per_lun, s->conf.cmd_per_lun);
 522     stl_raw(&scsiconf->event_info_size, sizeof(VirtIOSCSIEvent));
 523     stl_raw(&scsiconf->sense_size, s->sense_size);
 524     stl_raw(&scsiconf->cdb_size, s->cdb_size);
 525     stw_raw(&scsiconf->max_channel, VIRTIO_SCSI_MAX_CHANNEL);
 526     stw_raw(&scsiconf->max_target, VIRTIO_SCSI_MAX_TARGET);
 527     stl_raw(&scsiconf->max_lun, VIRTIO_SCSI_MAX_LUN);
 528 }
 529
 530 static void virtio_scsi_set_config(VirtIODevice *vdev,
 531                                    const uint8_t *config)
 532 {
 533     VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config;
 534     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 535
 536     if ((uint32_t) ldl_raw(&scsiconf->sense_size) >= 65536 ||
 537         (uint32_t) ldl_raw(&scsiconf->cdb_size) >= 256) {
 538         error_report("bad data written to virtio-scsi configuration space");
 539         exit(1);
 540     }
 541
 542     s->sense_size = ldl_raw(&scsiconf->sense_size);
 543     s->cdb_size = ldl_raw(&scsiconf->cdb_size);
 544 }
 545
 546 static uint32_t virtio_scsi_get_features(VirtIODevice *vdev,
 547                                          uint32_t requested_features)
 548 {
 549     return requested_features;
 550 }
 551
 552 static void virtio_scsi_reset(VirtIODevice *vdev)
 553 {
 554     VirtIOSCSI *s = (VirtIOSCSI *)vdev;
 555
 556     s->resetting++;
 557     qbus_reset_all(&s->bus.qbus);
 558     s->resetting--;
 559
 560     s->sense_size = VIRTIO_SCSI_SENSE_SIZE;
 561     s->cdb_size = VIRTIO_SCSI_CDB_SIZE;
 562     s->events_dropped = false;
 563 }
 564
 565 /* The device does not have anything to save beyond the virtio data.
 566  * Request data is saved with callbacks from SCSI devices.
 567  */
 568 static void virtio_scsi_save(QEMUFile *f, void *opaque)
 569 {
 570     VirtIODevice *vdev = VIRTIO_DEVICE(opaque);
 571     virtio_save(vdev, f);
 572 }
 573
 574 static int virtio_scsi_load(QEMUFile *f, void *opaque, int version_id)
 575 {
 576     VirtIODevice *vdev = VIRTIO_DEVICE(opaque);
 577     int ret;
 578
 579     ret = virtio_load(vdev, f);
 580     if (ret) {
 581         return ret;
 582     }
 583     return 0;
 584 }
 585
 586 static void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev,
 587                                    uint32_t event, uint32_t reason)
 588 {
 589     VirtIOSCSIReq *req = virtio_scsi_pop_req(s, s->event_vq);
 590     VirtIOSCSIEvent *evt;
 591     VirtIODevice *vdev = VIRTIO_DEVICE(s);
 592     int in_size;
 593
 594     if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
 595         return;
 596     }
 597
 598     if (!req) {
 599         s->events_dropped = true;
 600         return;
 601     }
 602
 603     if (req->elem.out_num || req->elem.in_num != 1) {
 604         virtio_scsi_bad_req();
 605     }
 606
 607     if (s->events_dropped) {
 608         event |= VIRTIO_SCSI_T_EVENTS_MISSED;
 609         s->events_dropped = false;
 610     }
 611
 612     in_size = req->elem.in_sg[0].iov_len;
 613     if (in_size < sizeof(VirtIOSCSIEvent)) {
 614         virtio_scsi_bad_req();
 615     }
 616
 617     evt = req->resp.event;
 618     memset(evt, 0, sizeof(VirtIOSCSIEvent));
 619     evt->event = event;
 620     evt->reason = reason;
 621     if (!dev) {
 622         assert(event == VIRTIO_SCSI_T_NO_EVENT);
 623     } else {
 624         evt->lun[0] = 1;
 625         evt->lun[1] = dev->id;
 626
 627         /* Linux wants us to keep the same encoding we use for REPORT LUNS.  */
 628         if (dev->lun >= 256) {
 629             evt->lun[2] = (dev->lun >> 8) | 0x40;
 630         }
 631         evt->lun[3] = dev->lun & 0xFF;
 632     }
 633     virtio_scsi_complete_req(req);
 634 }
 635
 636 static void virtio_scsi_handle_event(VirtIODevice *vdev, VirtQueue *vq)
 637 {
 638     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 639
 640     if (s->events_dropped) {
 641         virtio_scsi_push_event(s, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
 642     }
 643 }
 644
 645 static void virtio_scsi_change(SCSIBus *bus, SCSIDevice *dev, SCSISense sense)
 646 {
 647     VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus);
 648     VirtIODevice *vdev = VIRTIO_DEVICE(s);
 649
 650     if (((vdev->guest_features >> VIRTIO_SCSI_F_CHANGE) & 1) &&
 651         dev->type != TYPE_ROM) {
 652         virtio_scsi_push_event(s, dev, VIRTIO_SCSI_T_PARAM_CHANGE,
 653                                sense.asc | (sense.ascq << 8));
 654     }
 655 }
 656
 657 static void virtio_scsi_hotplug(SCSIBus *bus, SCSIDevice *dev)
 658 {
 659     VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus);
 660     VirtIODevice *vdev = VIRTIO_DEVICE(s);
 661
 662     if ((vdev->guest_features >> VIRTIO_SCSI_F_HOTPLUG) & 1) {
 663         virtio_scsi_push_event(s, dev, VIRTIO_SCSI_T_TRANSPORT_RESET,
 664                                VIRTIO_SCSI_EVT_RESET_RESCAN);
 665     }
 666 }
 667
 668 static void virtio_scsi_hot_unplug(SCSIBus *bus, SCSIDevice *dev)
 669 {
 670     VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus);
 671     VirtIODevice *vdev = VIRTIO_DEVICE(s);
 672
 673     if ((vdev->guest_features >> VIRTIO_SCSI_F_HOTPLUG) & 1) {
 674         virtio_scsi_push_event(s, dev, VIRTIO_SCSI_T_TRANSPORT_RESET,
 675                                VIRTIO_SCSI_EVT_RESET_REMOVED);
 676     }
 677 }
 678
 679 static struct SCSIBusInfo virtio_scsi_scsi_info = {
 680     .tcq = true,
 681     .max_channel = VIRTIO_SCSI_MAX_CHANNEL,
 682     .max_target = VIRTIO_SCSI_MAX_TARGET,
 683     .max_lun = VIRTIO_SCSI_MAX_LUN,
 684
 685     .complete = virtio_scsi_command_complete,
 686     .cancel = virtio_scsi_request_cancelled,
 687     .change = virtio_scsi_change,
 688     .hotplug = virtio_scsi_hotplug,
 689     .hot_unplug = virtio_scsi_hot_unplug,
 690     .get_sg_list = virtio_scsi_get_sg_list,
 691     .save_request = virtio_scsi_save_request,
 692     .load_request = virtio_scsi_load_request,
 693 };
 694
 695 static int virtio_scsi_device_init(VirtIODevice *vdev)
 696 {
 697     DeviceState *qdev = DEVICE(vdev);
 698     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 699     static int virtio_scsi_id;
 700     int i;
 701
 702     virtio_init(VIRTIO_DEVICE(s), "virtio-scsi", VIRTIO_ID_SCSI,
 703                 sizeof(VirtIOSCSIConfig));
 704
 705     s->cmd_vqs = g_malloc0(s->conf.num_queues * sizeof(VirtQueue *));
 706
 707     /* TODO set up vdev function pointers */
 708     vdev->get_config = virtio_scsi_get_config;
 709     vdev->set_config = virtio_scsi_set_config;
 710     vdev->get_features = virtio_scsi_get_features;
 711     vdev->reset = virtio_scsi_reset;
 712
 713     s->ctrl_vq = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE,
 714                                   virtio_scsi_handle_ctrl);
 715     s->event_vq = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE,
 716                                    virtio_scsi_handle_event);
 717     for (i = 0; i < s->conf.num_queues; i++) {
 718         s->cmd_vqs[i] = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE,
 719                                          virtio_scsi_handle_cmd);
 720     }
 721
 722     scsi_bus_new(&s->bus, qdev, &virtio_scsi_scsi_info);
 723     if (!qdev->hotplugged) {
 724         scsi_bus_legacy_handle_cmdline(&s->bus);
 725     }
 726
 727     register_savevm(qdev, "virtio-scsi", virtio_scsi_id++, 1,
 728                     virtio_scsi_save, virtio_scsi_load, s);
 729
 730     return 0;
 731 }
 732
 733 static int virtio_scsi_device_exit(DeviceState *qdev)
 734 {
 735     VirtIOSCSI *s = VIRTIO_SCSI(qdev);
 736     VirtIODevice *vdev = VIRTIO_DEVICE(qdev);
 737
 738     unregister_savevm(qdev, "virtio-scsi", s);
 739     g_free(s->cmd_vqs);
 740     virtio_common_cleanup(vdev);
 741     return 0;
 742 }
 743
 744 static Property virtio_scsi_properties[] = {
 745     DEFINE_VIRTIO_SCSI_PROPERTIES(VirtIOSCSI, conf),
 746     DEFINE_PROP_END_OF_LIST(),
 747 };
 748
 749 static void virtio_scsi_class_init(ObjectClass *klass, void *data)
 750 {
 751     DeviceClass *dc = DEVICE_CLASS(klass);
 752     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
 753     dc->exit = virtio_scsi_device_exit;
 754     dc->props = virtio_scsi_properties;
 755     vdc->init = virtio_scsi_device_init;
 756     vdc->get_config = virtio_scsi_get_config;
 757     vdc->set_config = virtio_scsi_set_config;
 758     vdc->get_features = virtio_scsi_get_features;
 759     vdc->reset = virtio_scsi_reset;
 760 }
 761
 762 static const TypeInfo virtio_scsi_info = {
 763     .name = TYPE_VIRTIO_SCSI,
 764     .parent = TYPE_VIRTIO_DEVICE,
 765     .instance_size = sizeof(VirtIOSCSI),
 766     .class_init = virtio_scsi_class_init,
 767 };
 768
 769 static void virtio_register_types(void)
 770 {
 771     type_register_static(&virtio_scsi_info);
 772 }
 773
 774 type_init(virtio_register_types)