xref: /openbmc/qemu/hw/scsi/scsi-bus.c (revision 61a67f71)
1 #include "qemu/osdep.h"
2 #include "hw/hw.h"
3 #include "qapi/error.h"
4 #include "qemu/error-report.h"
5 #include "hw/scsi/scsi.h"
6 #include "block/scsi.h"
7 #include "hw/qdev.h"
8 #include "sysemu/block-backend.h"
9 #include "sysemu/blockdev.h"
10 #include "trace.h"
11 #include "sysemu/dma.h"
12 #include "qemu/cutils.h"
13 
14 static char *scsibus_get_dev_path(DeviceState *dev);
15 static char *scsibus_get_fw_dev_path(DeviceState *dev);
16 static void scsi_req_dequeue(SCSIRequest *req);
17 static uint8_t *scsi_target_alloc_buf(SCSIRequest *req, size_t len);
18 static void scsi_target_free_buf(SCSIRequest *req);
19 
20 static Property scsi_props[] = {
21     DEFINE_PROP_UINT32("channel", SCSIDevice, channel, 0),
22     DEFINE_PROP_UINT32("scsi-id", SCSIDevice, id, -1),
23     DEFINE_PROP_UINT32("lun", SCSIDevice, lun, -1),
24     DEFINE_PROP_END_OF_LIST(),
25 };
26 
27 static void scsi_bus_class_init(ObjectClass *klass, void *data)
28 {
29     BusClass *k = BUS_CLASS(klass);
30     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
31 
32     k->get_dev_path = scsibus_get_dev_path;
33     k->get_fw_dev_path = scsibus_get_fw_dev_path;
34     hc->unplug = qdev_simple_device_unplug_cb;
35 }
36 
37 static const TypeInfo scsi_bus_info = {
38     .name = TYPE_SCSI_BUS,
39     .parent = TYPE_BUS,
40     .instance_size = sizeof(SCSIBus),
41     .class_init = scsi_bus_class_init,
42     .interfaces = (InterfaceInfo[]) {
43         { TYPE_HOTPLUG_HANDLER },
44         { }
45     }
46 };
47 static int next_scsi_bus;
48 
49 static void scsi_device_realize(SCSIDevice *s, Error **errp)
50 {
51     SCSIDeviceClass *sc = SCSI_DEVICE_GET_CLASS(s);
52     if (sc->realize) {
53         sc->realize(s, errp);
54     }
55 }
56 
57 int scsi_bus_parse_cdb(SCSIDevice *dev, SCSICommand *cmd, uint8_t *buf,
58                        void *hba_private)
59 {
60     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, dev->qdev.parent_bus);
61     int rc;
62 
63     assert(cmd->len == 0);
64     rc = scsi_req_parse_cdb(dev, cmd, buf);
65     if (bus->info->parse_cdb) {
66         rc = bus->info->parse_cdb(dev, cmd, buf, hba_private);
67     }
68     return rc;
69 }
70 
71 static SCSIRequest *scsi_device_alloc_req(SCSIDevice *s, uint32_t tag, uint32_t lun,
72                                           uint8_t *buf, void *hba_private)
73 {
74     SCSIDeviceClass *sc = SCSI_DEVICE_GET_CLASS(s);
75     if (sc->alloc_req) {
76         return sc->alloc_req(s, tag, lun, buf, hba_private);
77     }
78 
79     return NULL;
80 }
81 
82 void scsi_device_unit_attention_reported(SCSIDevice *s)
83 {
84     SCSIDeviceClass *sc = SCSI_DEVICE_GET_CLASS(s);
85     if (sc->unit_attention_reported) {
86         sc->unit_attention_reported(s);
87     }
88 }
89 
90 /* Create a scsi bus, and attach devices to it.  */
91 void scsi_bus_new(SCSIBus *bus, size_t bus_size, DeviceState *host,
92                   const SCSIBusInfo *info, const char *bus_name)
93 {
94     qbus_create_inplace(bus, bus_size, TYPE_SCSI_BUS, host, bus_name);
95     bus->busnr = next_scsi_bus++;
96     bus->info = info;
97     qbus_set_bus_hotplug_handler(BUS(bus), &error_abort);
98 }
99 
100 static void scsi_dma_restart_bh(void *opaque)
101 {
102     SCSIDevice *s = opaque;
103     SCSIRequest *req, *next;
104 
105     qemu_bh_delete(s->bh);
106     s->bh = NULL;
107 
108     aio_context_acquire(blk_get_aio_context(s->conf.blk));
109     QTAILQ_FOREACH_SAFE(req, &s->requests, next, next) {
110         scsi_req_ref(req);
111         if (req->retry) {
112             req->retry = false;
113             switch (req->cmd.mode) {
114             case SCSI_XFER_FROM_DEV:
115             case SCSI_XFER_TO_DEV:
116                 scsi_req_continue(req);
117                 break;
118             case SCSI_XFER_NONE:
119                 scsi_req_dequeue(req);
120                 scsi_req_enqueue(req);
121                 break;
122             }
123         }
124         scsi_req_unref(req);
125     }
126     aio_context_release(blk_get_aio_context(s->conf.blk));
127 }
128 
129 void scsi_req_retry(SCSIRequest *req)
130 {
131     /* No need to save a reference, because scsi_dma_restart_bh just
132      * looks at the request list.  */
133     req->retry = true;
134 }
135 
136 static void scsi_dma_restart_cb(void *opaque, int running, RunState state)
137 {
138     SCSIDevice *s = opaque;
139 
140     if (!running) {
141         return;
142     }
143     if (!s->bh) {
144         AioContext *ctx = blk_get_aio_context(s->conf.blk);
145         s->bh = aio_bh_new(ctx, scsi_dma_restart_bh, s);
146         qemu_bh_schedule(s->bh);
147     }
148 }
149 
150 static void scsi_qdev_realize(DeviceState *qdev, Error **errp)
151 {
152     SCSIDevice *dev = SCSI_DEVICE(qdev);
153     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, dev->qdev.parent_bus);
154     SCSIDevice *d;
155     Error *local_err = NULL;
156 
157     if (dev->channel > bus->info->max_channel) {
158         error_setg(errp, "bad scsi channel id: %d", dev->channel);
159         return;
160     }
161     if (dev->id != -1 && dev->id > bus->info->max_target) {
162         error_setg(errp, "bad scsi device id: %d", dev->id);
163         return;
164     }
165     if (dev->lun != -1 && dev->lun > bus->info->max_lun) {
166         error_setg(errp, "bad scsi device lun: %d", dev->lun);
167         return;
168     }
169 
170     if (dev->id == -1) {
171         int id = -1;
172         if (dev->lun == -1) {
173             dev->lun = 0;
174         }
175         do {
176             d = scsi_device_find(bus, dev->channel, ++id, dev->lun);
177         } while (d && d->lun == dev->lun && id < bus->info->max_target);
178         if (d && d->lun == dev->lun) {
179             error_setg(errp, "no free target");
180             return;
181         }
182         dev->id = id;
183     } else if (dev->lun == -1) {
184         int lun = -1;
185         do {
186             d = scsi_device_find(bus, dev->channel, dev->id, ++lun);
187         } while (d && d->lun == lun && lun < bus->info->max_lun);
188         if (d && d->lun == lun) {
189             error_setg(errp, "no free lun");
190             return;
191         }
192         dev->lun = lun;
193     } else {
194         d = scsi_device_find(bus, dev->channel, dev->id, dev->lun);
195         assert(d);
196         if (d->lun == dev->lun && dev != d) {
197             error_setg(errp, "lun already used by '%s'", d->qdev.id);
198             return;
199         }
200     }
201 
202     QTAILQ_INIT(&dev->requests);
203     scsi_device_realize(dev, &local_err);
204     if (local_err) {
205         error_propagate(errp, local_err);
206         return;
207     }
208     dev->vmsentry = qemu_add_vm_change_state_handler(scsi_dma_restart_cb,
209                                                      dev);
210 }
211 
212 static void scsi_qdev_unrealize(DeviceState *qdev, Error **errp)
213 {
214     SCSIDevice *dev = SCSI_DEVICE(qdev);
215 
216     if (dev->vmsentry) {
217         qemu_del_vm_change_state_handler(dev->vmsentry);
218     }
219 
220     scsi_device_purge_requests(dev, SENSE_CODE(NO_SENSE));
221     blockdev_mark_auto_del(dev->conf.blk);
222 }
223 
224 /* handle legacy '-drive if=scsi,...' cmd line args */
225 SCSIDevice *scsi_bus_legacy_add_drive(SCSIBus *bus, BlockBackend *blk,
226                                       int unit, bool removable, int bootindex,
227                                       const char *serial, Error **errp)
228 {
229     const char *driver;
230     char *name;
231     DeviceState *dev;
232     Error *err = NULL;
233 
234     driver = blk_is_sg(blk) ? "scsi-generic" : "scsi-disk";
235     dev = qdev_create(&bus->qbus, driver);
236     name = g_strdup_printf("legacy[%d]", unit);
237     object_property_add_child(OBJECT(bus), name, OBJECT(dev), NULL);
238     g_free(name);
239 
240     qdev_prop_set_uint32(dev, "scsi-id", unit);
241     if (bootindex >= 0) {
242         object_property_set_int(OBJECT(dev), bootindex, "bootindex",
243                                 &error_abort);
244     }
245     if (object_property_find(OBJECT(dev), "removable", NULL)) {
246         qdev_prop_set_bit(dev, "removable", removable);
247     }
248     if (serial && object_property_find(OBJECT(dev), "serial", NULL)) {
249         qdev_prop_set_string(dev, "serial", serial);
250     }
251     qdev_prop_set_drive(dev, "drive", blk, &err);
252     if (err) {
253         error_propagate(errp, err);
254         object_unparent(OBJECT(dev));
255         return NULL;
256     }
257     object_property_set_bool(OBJECT(dev), true, "realized", &err);
258     if (err != NULL) {
259         error_propagate(errp, err);
260         object_unparent(OBJECT(dev));
261         return NULL;
262     }
263     return SCSI_DEVICE(dev);
264 }
265 
266 void scsi_bus_legacy_handle_cmdline(SCSIBus *bus, bool deprecated)
267 {
268     Location loc;
269     DriveInfo *dinfo;
270     int unit;
271 
272     loc_push_none(&loc);
273     for (unit = 0; unit <= bus->info->max_target; unit++) {
274         dinfo = drive_get(IF_SCSI, bus->busnr, unit);
275         if (dinfo == NULL) {
276             continue;
277         }
278         qemu_opts_loc_restore(dinfo->opts);
279         if (deprecated) {
280             /* Handling -drive not claimed by machine initialization */
281             if (blk_get_attached_dev(blk_by_legacy_dinfo(dinfo))) {
282                 continue;       /* claimed */
283             }
284             if (!dinfo->is_default) {
285                 warn_report("bus=%d,unit=%d is deprecated with this"
286                             " machine type",
287                             bus->busnr, unit);
288             }
289         }
290         scsi_bus_legacy_add_drive(bus, blk_by_legacy_dinfo(dinfo),
291                                   unit, false, -1, NULL, &error_fatal);
292     }
293     loc_pop(&loc);
294 }
295 
296 static bool is_scsi_hba_with_legacy_magic(Object *obj)
297 {
298     static const char *magic[] = {
299         "am53c974", "dc390", "esp", "lsi53c810", "lsi53c895a",
300         "megasas", "megasas-gen2", "mptsas1068", "spapr-vscsi",
301         "virtio-scsi-device",
302         NULL
303     };
304     const char *typename = object_get_typename(obj);
305     int i;
306 
307     for (i = 0; magic[i]; i++)
308         if (!strcmp(typename, magic[i])) {
309             return true;
310     }
311 
312     return false;
313 }
314 
315 static int scsi_legacy_handle_cmdline_cb(Object *obj, void *opaque)
316 {
317     SCSIBus *bus = (SCSIBus *)object_dynamic_cast(obj, TYPE_SCSI_BUS);
318 
319     if (bus && is_scsi_hba_with_legacy_magic(OBJECT(bus->qbus.parent))) {
320         scsi_bus_legacy_handle_cmdline(bus, true);
321     }
322 
323     return 0;
324 }
325 
326 void scsi_legacy_handle_cmdline(void)
327 {
328     object_child_foreach_recursive(object_get_root(),
329                                    scsi_legacy_handle_cmdline_cb, NULL);
330 }
331 
332 static int32_t scsi_invalid_field(SCSIRequest *req, uint8_t *buf)
333 {
334     scsi_req_build_sense(req, SENSE_CODE(INVALID_FIELD));
335     scsi_req_complete(req, CHECK_CONDITION);
336     return 0;
337 }
338 
339 static const struct SCSIReqOps reqops_invalid_field = {
340     .size         = sizeof(SCSIRequest),
341     .send_command = scsi_invalid_field
342 };
343 
344 /* SCSIReqOps implementation for invalid commands.  */
345 
346 static int32_t scsi_invalid_command(SCSIRequest *req, uint8_t *buf)
347 {
348     scsi_req_build_sense(req, SENSE_CODE(INVALID_OPCODE));
349     scsi_req_complete(req, CHECK_CONDITION);
350     return 0;
351 }
352 
353 static const struct SCSIReqOps reqops_invalid_opcode = {
354     .size         = sizeof(SCSIRequest),
355     .send_command = scsi_invalid_command
356 };
357 
358 /* SCSIReqOps implementation for unit attention conditions.  */
359 
360 static int32_t scsi_unit_attention(SCSIRequest *req, uint8_t *buf)
361 {
362     if (req->dev->unit_attention.key == UNIT_ATTENTION) {
363         scsi_req_build_sense(req, req->dev->unit_attention);
364     } else if (req->bus->unit_attention.key == UNIT_ATTENTION) {
365         scsi_req_build_sense(req, req->bus->unit_attention);
366     }
367     scsi_req_complete(req, CHECK_CONDITION);
368     return 0;
369 }
370 
371 static const struct SCSIReqOps reqops_unit_attention = {
372     .size         = sizeof(SCSIRequest),
373     .send_command = scsi_unit_attention
374 };
375 
376 /* SCSIReqOps implementation for REPORT LUNS and for commands sent to
377    an invalid LUN.  */
378 
379 typedef struct SCSITargetReq SCSITargetReq;
380 
381 struct SCSITargetReq {
382     SCSIRequest req;
383     int len;
384     uint8_t *buf;
385     int buf_len;
386 };
387 
388 static void store_lun(uint8_t *outbuf, int lun)
389 {
390     if (lun < 256) {
391         outbuf[1] = lun;
392         return;
393     }
394     outbuf[1] = (lun & 255);
395     outbuf[0] = (lun >> 8) | 0x40;
396 }
397 
398 static bool scsi_target_emulate_report_luns(SCSITargetReq *r)
399 {
400     BusChild *kid;
401     int i, len, n;
402     int channel, id;
403     bool found_lun0;
404 
405     if (r->req.cmd.xfer < 16) {
406         return false;
407     }
408     if (r->req.cmd.buf[2] > 2) {
409         return false;
410     }
411     channel = r->req.dev->channel;
412     id = r->req.dev->id;
413     found_lun0 = false;
414     n = 0;
415     QTAILQ_FOREACH(kid, &r->req.bus->qbus.children, sibling) {
416         DeviceState *qdev = kid->child;
417         SCSIDevice *dev = SCSI_DEVICE(qdev);
418 
419         if (dev->channel == channel && dev->id == id) {
420             if (dev->lun == 0) {
421                 found_lun0 = true;
422             }
423             n += 8;
424         }
425     }
426     if (!found_lun0) {
427         n += 8;
428     }
429 
430     scsi_target_alloc_buf(&r->req, n + 8);
431 
432     len = MIN(n + 8, r->req.cmd.xfer & ~7);
433     memset(r->buf, 0, len);
434     stl_be_p(&r->buf[0], n);
435     i = found_lun0 ? 8 : 16;
436     QTAILQ_FOREACH(kid, &r->req.bus->qbus.children, sibling) {
437         DeviceState *qdev = kid->child;
438         SCSIDevice *dev = SCSI_DEVICE(qdev);
439 
440         if (dev->channel == channel && dev->id == id) {
441             store_lun(&r->buf[i], dev->lun);
442             i += 8;
443         }
444     }
445     assert(i == n + 8);
446     r->len = len;
447     return true;
448 }
449 
450 static bool scsi_target_emulate_inquiry(SCSITargetReq *r)
451 {
452     assert(r->req.dev->lun != r->req.lun);
453 
454     scsi_target_alloc_buf(&r->req, SCSI_INQUIRY_LEN);
455 
456     if (r->req.cmd.buf[1] & 0x2) {
457         /* Command support data - optional, not implemented */
458         return false;
459     }
460 
461     if (r->req.cmd.buf[1] & 0x1) {
462         /* Vital product data */
463         uint8_t page_code = r->req.cmd.buf[2];
464         r->buf[r->len++] = page_code ; /* this page */
465         r->buf[r->len++] = 0x00;
466 
467         switch (page_code) {
468         case 0x00: /* Supported page codes, mandatory */
469         {
470             int pages;
471             pages = r->len++;
472             r->buf[r->len++] = 0x00; /* list of supported pages (this page) */
473             r->buf[pages] = r->len - pages - 1; /* number of pages */
474             break;
475         }
476         default:
477             return false;
478         }
479         /* done with EVPD */
480         assert(r->len < r->buf_len);
481         r->len = MIN(r->req.cmd.xfer, r->len);
482         return true;
483     }
484 
485     /* Standard INQUIRY data */
486     if (r->req.cmd.buf[2] != 0) {
487         return false;
488     }
489 
490     /* PAGE CODE == 0 */
491     r->len = MIN(r->req.cmd.xfer, SCSI_INQUIRY_LEN);
492     memset(r->buf, 0, r->len);
493     if (r->req.lun != 0) {
494         r->buf[0] = TYPE_NO_LUN;
495     } else {
496         r->buf[0] = TYPE_NOT_PRESENT | TYPE_INACTIVE;
497         r->buf[2] = 5; /* Version */
498         r->buf[3] = 2 | 0x10; /* HiSup, response data format */
499         r->buf[4] = r->len - 5; /* Additional Length = (Len - 1) - 4 */
500         r->buf[7] = 0x10 | (r->req.bus->info->tcq ? 0x02 : 0); /* Sync, TCQ.  */
501         memcpy(&r->buf[8], "QEMU    ", 8);
502         memcpy(&r->buf[16], "QEMU TARGET     ", 16);
503         pstrcpy((char *) &r->buf[32], 4, qemu_hw_version());
504     }
505     return true;
506 }
507 
508 static size_t scsi_sense_len(SCSIRequest *req)
509 {
510     if (req->dev->type == TYPE_SCANNER)
511         return SCSI_SENSE_LEN_SCANNER;
512     else
513         return SCSI_SENSE_LEN;
514 }
515 
516 static int32_t scsi_target_send_command(SCSIRequest *req, uint8_t *buf)
517 {
518     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
519 
520     switch (buf[0]) {
521     case REPORT_LUNS:
522         if (!scsi_target_emulate_report_luns(r)) {
523             goto illegal_request;
524         }
525         break;
526     case INQUIRY:
527         if (!scsi_target_emulate_inquiry(r)) {
528             goto illegal_request;
529         }
530         break;
531     case REQUEST_SENSE:
532         scsi_target_alloc_buf(&r->req, scsi_sense_len(req));
533         r->len = scsi_device_get_sense(r->req.dev, r->buf,
534                                        MIN(req->cmd.xfer, r->buf_len),
535                                        (req->cmd.buf[1] & 1) == 0);
536         if (r->req.dev->sense_is_ua) {
537             scsi_device_unit_attention_reported(req->dev);
538             r->req.dev->sense_len = 0;
539             r->req.dev->sense_is_ua = false;
540         }
541         break;
542     case TEST_UNIT_READY:
543         break;
544     default:
545         scsi_req_build_sense(req, SENSE_CODE(LUN_NOT_SUPPORTED));
546         scsi_req_complete(req, CHECK_CONDITION);
547         return 0;
548     illegal_request:
549         scsi_req_build_sense(req, SENSE_CODE(INVALID_FIELD));
550         scsi_req_complete(req, CHECK_CONDITION);
551         return 0;
552     }
553 
554     if (!r->len) {
555         scsi_req_complete(req, GOOD);
556     }
557     return r->len;
558 }
559 
560 static void scsi_target_read_data(SCSIRequest *req)
561 {
562     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
563     uint32_t n;
564 
565     n = r->len;
566     if (n > 0) {
567         r->len = 0;
568         scsi_req_data(&r->req, n);
569     } else {
570         scsi_req_complete(&r->req, GOOD);
571     }
572 }
573 
574 static uint8_t *scsi_target_get_buf(SCSIRequest *req)
575 {
576     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
577 
578     return r->buf;
579 }
580 
581 static uint8_t *scsi_target_alloc_buf(SCSIRequest *req, size_t len)
582 {
583     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
584 
585     r->buf = g_malloc(len);
586     r->buf_len = len;
587 
588     return r->buf;
589 }
590 
591 static void scsi_target_free_buf(SCSIRequest *req)
592 {
593     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
594 
595     g_free(r->buf);
596 }
597 
598 static const struct SCSIReqOps reqops_target_command = {
599     .size         = sizeof(SCSITargetReq),
600     .send_command = scsi_target_send_command,
601     .read_data    = scsi_target_read_data,
602     .get_buf      = scsi_target_get_buf,
603     .free_req     = scsi_target_free_buf,
604 };
605 
606 
607 SCSIRequest *scsi_req_alloc(const SCSIReqOps *reqops, SCSIDevice *d,
608                             uint32_t tag, uint32_t lun, void *hba_private)
609 {
610     SCSIRequest *req;
611     SCSIBus *bus = scsi_bus_from_device(d);
612     BusState *qbus = BUS(bus);
613     const int memset_off = offsetof(SCSIRequest, sense)
614                            + sizeof(req->sense);
615 
616     req = g_malloc(reqops->size);
617     memset((uint8_t *)req + memset_off, 0, reqops->size - memset_off);
618     req->refcount = 1;
619     req->bus = bus;
620     req->dev = d;
621     req->tag = tag;
622     req->lun = lun;
623     req->hba_private = hba_private;
624     req->status = -1;
625     req->ops = reqops;
626     object_ref(OBJECT(d));
627     object_ref(OBJECT(qbus->parent));
628     notifier_list_init(&req->cancel_notifiers);
629     trace_scsi_req_alloc(req->dev->id, req->lun, req->tag);
630     return req;
631 }
632 
633 SCSIRequest *scsi_req_new(SCSIDevice *d, uint32_t tag, uint32_t lun,
634                           uint8_t *buf, void *hba_private)
635 {
636     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, d->qdev.parent_bus);
637     const SCSIReqOps *ops;
638     SCSIDeviceClass *sc = SCSI_DEVICE_GET_CLASS(d);
639     SCSIRequest *req;
640     SCSICommand cmd = { .len = 0 };
641     int ret;
642 
643     if ((d->unit_attention.key == UNIT_ATTENTION ||
644          bus->unit_attention.key == UNIT_ATTENTION) &&
645         (buf[0] != INQUIRY &&
646          buf[0] != REPORT_LUNS &&
647          buf[0] != GET_CONFIGURATION &&
648          buf[0] != GET_EVENT_STATUS_NOTIFICATION &&
649 
650          /*
651           * If we already have a pending unit attention condition,
652           * report this one before triggering another one.
653           */
654          !(buf[0] == REQUEST_SENSE && d->sense_is_ua))) {
655         ops = &reqops_unit_attention;
656     } else if (lun != d->lun ||
657                buf[0] == REPORT_LUNS ||
658                (buf[0] == REQUEST_SENSE && d->sense_len)) {
659         ops = &reqops_target_command;
660     } else {
661         ops = NULL;
662     }
663 
664     if (ops != NULL || !sc->parse_cdb) {
665         ret = scsi_req_parse_cdb(d, &cmd, buf);
666     } else {
667         ret = sc->parse_cdb(d, &cmd, buf, hba_private);
668     }
669 
670     if (ret != 0) {
671         trace_scsi_req_parse_bad(d->id, lun, tag, buf[0]);
672         req = scsi_req_alloc(&reqops_invalid_opcode, d, tag, lun, hba_private);
673     } else {
674         assert(cmd.len != 0);
675         trace_scsi_req_parsed(d->id, lun, tag, buf[0],
676                               cmd.mode, cmd.xfer);
677         if (cmd.lba != -1) {
678             trace_scsi_req_parsed_lba(d->id, lun, tag, buf[0],
679                                       cmd.lba);
680         }
681 
682         if (cmd.xfer > INT32_MAX) {
683             req = scsi_req_alloc(&reqops_invalid_field, d, tag, lun, hba_private);
684         } else if (ops) {
685             req = scsi_req_alloc(ops, d, tag, lun, hba_private);
686         } else {
687             req = scsi_device_alloc_req(d, tag, lun, buf, hba_private);
688         }
689     }
690 
691     req->cmd = cmd;
692     req->resid = req->cmd.xfer;
693 
694     switch (buf[0]) {
695     case INQUIRY:
696         trace_scsi_inquiry(d->id, lun, tag, cmd.buf[1], cmd.buf[2]);
697         break;
698     case TEST_UNIT_READY:
699         trace_scsi_test_unit_ready(d->id, lun, tag);
700         break;
701     case REPORT_LUNS:
702         trace_scsi_report_luns(d->id, lun, tag);
703         break;
704     case REQUEST_SENSE:
705         trace_scsi_request_sense(d->id, lun, tag);
706         break;
707     default:
708         break;
709     }
710 
711     return req;
712 }
713 
714 uint8_t *scsi_req_get_buf(SCSIRequest *req)
715 {
716     return req->ops->get_buf(req);
717 }
718 
719 static void scsi_clear_unit_attention(SCSIRequest *req)
720 {
721     SCSISense *ua;
722     if (req->dev->unit_attention.key != UNIT_ATTENTION &&
723         req->bus->unit_attention.key != UNIT_ATTENTION) {
724         return;
725     }
726 
727     /*
728      * If an INQUIRY command enters the enabled command state,
729      * the device server shall [not] clear any unit attention condition;
730      * See also MMC-6, paragraphs 6.5 and 6.6.2.
731      */
732     if (req->cmd.buf[0] == INQUIRY ||
733         req->cmd.buf[0] == GET_CONFIGURATION ||
734         req->cmd.buf[0] == GET_EVENT_STATUS_NOTIFICATION) {
735         return;
736     }
737 
738     if (req->dev->unit_attention.key == UNIT_ATTENTION) {
739         ua = &req->dev->unit_attention;
740     } else {
741         ua = &req->bus->unit_attention;
742     }
743 
744     /*
745      * If a REPORT LUNS command enters the enabled command state, [...]
746      * the device server shall clear any pending unit attention condition
747      * with an additional sense code of REPORTED LUNS DATA HAS CHANGED.
748      */
749     if (req->cmd.buf[0] == REPORT_LUNS &&
750         !(ua->asc == SENSE_CODE(REPORTED_LUNS_CHANGED).asc &&
751           ua->ascq == SENSE_CODE(REPORTED_LUNS_CHANGED).ascq)) {
752         return;
753     }
754 
755     *ua = SENSE_CODE(NO_SENSE);
756 }
757 
758 int scsi_req_get_sense(SCSIRequest *req, uint8_t *buf, int len)
759 {
760     int ret;
761 
762     assert(len >= 14);
763     if (!req->sense_len) {
764         return 0;
765     }
766 
767     ret = scsi_build_sense(req->sense, req->sense_len, buf, len, true);
768 
769     /*
770      * FIXME: clearing unit attention conditions upon autosense should be done
771      * only if the UA_INTLCK_CTRL field in the Control mode page is set to 00b
772      * (SAM-5, 5.14).
773      *
774      * We assume UA_INTLCK_CTRL to be 00b for HBAs that support autosense, and
775      * 10b for HBAs that do not support it (do not call scsi_req_get_sense).
776      * Here we handle unit attention clearing for UA_INTLCK_CTRL == 00b.
777      */
778     if (req->dev->sense_is_ua) {
779         scsi_device_unit_attention_reported(req->dev);
780         req->dev->sense_len = 0;
781         req->dev->sense_is_ua = false;
782     }
783     return ret;
784 }
785 
786 int scsi_device_get_sense(SCSIDevice *dev, uint8_t *buf, int len, bool fixed)
787 {
788     return scsi_build_sense(dev->sense, dev->sense_len, buf, len, fixed);
789 }
790 
791 void scsi_req_build_sense(SCSIRequest *req, SCSISense sense)
792 {
793     trace_scsi_req_build_sense(req->dev->id, req->lun, req->tag,
794                                sense.key, sense.asc, sense.ascq);
795     memset(req->sense, 0, 18);
796     req->sense[0] = 0x70;
797     req->sense[2] = sense.key;
798     req->sense[7] = 10;
799     req->sense[12] = sense.asc;
800     req->sense[13] = sense.ascq;
801     req->sense_len = 18;
802 }
803 
804 static void scsi_req_enqueue_internal(SCSIRequest *req)
805 {
806     assert(!req->enqueued);
807     scsi_req_ref(req);
808     if (req->bus->info->get_sg_list) {
809         req->sg = req->bus->info->get_sg_list(req);
810     } else {
811         req->sg = NULL;
812     }
813     req->enqueued = true;
814     QTAILQ_INSERT_TAIL(&req->dev->requests, req, next);
815 }
816 
817 int32_t scsi_req_enqueue(SCSIRequest *req)
818 {
819     int32_t rc;
820 
821     assert(!req->retry);
822     scsi_req_enqueue_internal(req);
823     scsi_req_ref(req);
824     rc = req->ops->send_command(req, req->cmd.buf);
825     scsi_req_unref(req);
826     return rc;
827 }
828 
829 static void scsi_req_dequeue(SCSIRequest *req)
830 {
831     trace_scsi_req_dequeue(req->dev->id, req->lun, req->tag);
832     req->retry = false;
833     if (req->enqueued) {
834         QTAILQ_REMOVE(&req->dev->requests, req, next);
835         req->enqueued = false;
836         scsi_req_unref(req);
837     }
838 }
839 
840 static int scsi_get_performance_length(int num_desc, int type, int data_type)
841 {
842     /* MMC-6, paragraph 6.7.  */
843     switch (type) {
844     case 0:
845         if ((data_type & 3) == 0) {
846             /* Each descriptor is as in Table 295 - Nominal performance.  */
847             return 16 * num_desc + 8;
848         } else {
849             /* Each descriptor is as in Table 296 - Exceptions.  */
850             return 6 * num_desc + 8;
851         }
852     case 1:
853     case 4:
854     case 5:
855         return 8 * num_desc + 8;
856     case 2:
857         return 2048 * num_desc + 8;
858     case 3:
859         return 16 * num_desc + 8;
860     default:
861         return 8;
862     }
863 }
864 
865 static int ata_passthrough_xfer_unit(SCSIDevice *dev, uint8_t *buf)
866 {
867     int byte_block = (buf[2] >> 2) & 0x1;
868     int type = (buf[2] >> 4) & 0x1;
869     int xfer_unit;
870 
871     if (byte_block) {
872         if (type) {
873             xfer_unit = dev->blocksize;
874         } else {
875             xfer_unit = 512;
876         }
877     } else {
878         xfer_unit = 1;
879     }
880 
881     return xfer_unit;
882 }
883 
884 static int ata_passthrough_12_xfer(SCSIDevice *dev, uint8_t *buf)
885 {
886     int length = buf[2] & 0x3;
887     int xfer;
888     int unit = ata_passthrough_xfer_unit(dev, buf);
889 
890     switch (length) {
891     case 0:
892     case 3: /* USB-specific.  */
893     default:
894         xfer = 0;
895         break;
896     case 1:
897         xfer = buf[3];
898         break;
899     case 2:
900         xfer = buf[4];
901         break;
902     }
903 
904     return xfer * unit;
905 }
906 
907 static int ata_passthrough_16_xfer(SCSIDevice *dev, uint8_t *buf)
908 {
909     int extend = buf[1] & 0x1;
910     int length = buf[2] & 0x3;
911     int xfer;
912     int unit = ata_passthrough_xfer_unit(dev, buf);
913 
914     switch (length) {
915     case 0:
916     case 3: /* USB-specific.  */
917     default:
918         xfer = 0;
919         break;
920     case 1:
921         xfer = buf[4];
922         xfer |= (extend ? buf[3] << 8 : 0);
923         break;
924     case 2:
925         xfer = buf[6];
926         xfer |= (extend ? buf[5] << 8 : 0);
927         break;
928     }
929 
930     return xfer * unit;
931 }
932 
933 uint32_t scsi_data_cdb_xfer(uint8_t *buf)
934 {
935     if ((buf[0] >> 5) == 0 && buf[4] == 0) {
936         return 256;
937     } else {
938         return scsi_cdb_xfer(buf);
939     }
940 }
941 
942 uint32_t scsi_cdb_xfer(uint8_t *buf)
943 {
944     switch (buf[0] >> 5) {
945     case 0:
946         return buf[4];
947         break;
948     case 1:
949     case 2:
950         return lduw_be_p(&buf[7]);
951         break;
952     case 4:
953         return ldl_be_p(&buf[10]) & 0xffffffffULL;
954         break;
955     case 5:
956         return ldl_be_p(&buf[6]) & 0xffffffffULL;
957         break;
958     default:
959         return -1;
960     }
961 }
962 
963 static int scsi_req_xfer(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
964 {
965     cmd->xfer = scsi_cdb_xfer(buf);
966     switch (buf[0]) {
967     case TEST_UNIT_READY:
968     case REWIND:
969     case START_STOP:
970     case SET_CAPACITY:
971     case WRITE_FILEMARKS:
972     case WRITE_FILEMARKS_16:
973     case SPACE:
974     case RESERVE:
975     case RELEASE:
976     case ERASE:
977     case ALLOW_MEDIUM_REMOVAL:
978     case SEEK_10:
979     case SYNCHRONIZE_CACHE:
980     case SYNCHRONIZE_CACHE_16:
981     case LOCATE_16:
982     case LOCK_UNLOCK_CACHE:
983     case SET_CD_SPEED:
984     case SET_LIMITS:
985     case WRITE_LONG_10:
986     case UPDATE_BLOCK:
987     case RESERVE_TRACK:
988     case SET_READ_AHEAD:
989     case PRE_FETCH:
990     case PRE_FETCH_16:
991     case ALLOW_OVERWRITE:
992         cmd->xfer = 0;
993         break;
994     case VERIFY_10:
995     case VERIFY_12:
996     case VERIFY_16:
997         if ((buf[1] & 2) == 0) {
998             cmd->xfer = 0;
999         } else if ((buf[1] & 4) != 0) {
1000             cmd->xfer = 1;
1001         }
1002         cmd->xfer *= dev->blocksize;
1003         break;
1004     case MODE_SENSE:
1005         break;
1006     case WRITE_SAME_10:
1007     case WRITE_SAME_16:
1008         cmd->xfer = dev->blocksize;
1009         break;
1010     case READ_CAPACITY_10:
1011         cmd->xfer = 8;
1012         break;
1013     case READ_BLOCK_LIMITS:
1014         cmd->xfer = 6;
1015         break;
1016     case SEND_VOLUME_TAG:
1017         /* GPCMD_SET_STREAMING from multimedia commands.  */
1018         if (dev->type == TYPE_ROM) {
1019             cmd->xfer = buf[10] | (buf[9] << 8);
1020         } else {
1021             cmd->xfer = buf[9] | (buf[8] << 8);
1022         }
1023         break;
1024     case WRITE_6:
1025         /* length 0 means 256 blocks */
1026         if (cmd->xfer == 0) {
1027             cmd->xfer = 256;
1028         }
1029         /* fall through */
1030     case WRITE_10:
1031     case WRITE_VERIFY_10:
1032     case WRITE_12:
1033     case WRITE_VERIFY_12:
1034     case WRITE_16:
1035     case WRITE_VERIFY_16:
1036         cmd->xfer *= dev->blocksize;
1037         break;
1038     case READ_6:
1039     case READ_REVERSE:
1040         /* length 0 means 256 blocks */
1041         if (cmd->xfer == 0) {
1042             cmd->xfer = 256;
1043         }
1044         /* fall through */
1045     case READ_10:
1046     case READ_12:
1047     case READ_16:
1048         cmd->xfer *= dev->blocksize;
1049         break;
1050     case FORMAT_UNIT:
1051         /* MMC mandates the parameter list to be 12-bytes long.  Parameters
1052          * for block devices are restricted to the header right now.  */
1053         if (dev->type == TYPE_ROM && (buf[1] & 16)) {
1054             cmd->xfer = 12;
1055         } else {
1056             cmd->xfer = (buf[1] & 16) == 0 ? 0 : (buf[1] & 32 ? 8 : 4);
1057         }
1058         break;
1059     case INQUIRY:
1060     case RECEIVE_DIAGNOSTIC:
1061     case SEND_DIAGNOSTIC:
1062         cmd->xfer = buf[4] | (buf[3] << 8);
1063         break;
1064     case READ_CD:
1065     case READ_BUFFER:
1066     case WRITE_BUFFER:
1067     case SEND_CUE_SHEET:
1068         cmd->xfer = buf[8] | (buf[7] << 8) | (buf[6] << 16);
1069         break;
1070     case PERSISTENT_RESERVE_OUT:
1071         cmd->xfer = ldl_be_p(&buf[5]) & 0xffffffffULL;
1072         break;
1073     case ERASE_12:
1074         if (dev->type == TYPE_ROM) {
1075             /* MMC command GET PERFORMANCE.  */
1076             cmd->xfer = scsi_get_performance_length(buf[9] | (buf[8] << 8),
1077                                                     buf[10], buf[1] & 0x1f);
1078         }
1079         break;
1080     case MECHANISM_STATUS:
1081     case READ_DVD_STRUCTURE:
1082     case SEND_DVD_STRUCTURE:
1083     case MAINTENANCE_OUT:
1084     case MAINTENANCE_IN:
1085         if (dev->type == TYPE_ROM) {
1086             /* GPCMD_REPORT_KEY and GPCMD_SEND_KEY from multi media commands */
1087             cmd->xfer = buf[9] | (buf[8] << 8);
1088         }
1089         break;
1090     case ATA_PASSTHROUGH_12:
1091         if (dev->type == TYPE_ROM) {
1092             /* BLANK command of MMC */
1093             cmd->xfer = 0;
1094         } else {
1095             cmd->xfer = ata_passthrough_12_xfer(dev, buf);
1096         }
1097         break;
1098     case ATA_PASSTHROUGH_16:
1099         cmd->xfer = ata_passthrough_16_xfer(dev, buf);
1100         break;
1101     }
1102     return 0;
1103 }
1104 
1105 static int scsi_req_stream_xfer(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
1106 {
1107     switch (buf[0]) {
1108     /* stream commands */
1109     case ERASE_12:
1110     case ERASE_16:
1111         cmd->xfer = 0;
1112         break;
1113     case READ_6:
1114     case READ_REVERSE:
1115     case RECOVER_BUFFERED_DATA:
1116     case WRITE_6:
1117         cmd->xfer = buf[4] | (buf[3] << 8) | (buf[2] << 16);
1118         if (buf[1] & 0x01) { /* fixed */
1119             cmd->xfer *= dev->blocksize;
1120         }
1121         break;
1122     case READ_16:
1123     case READ_REVERSE_16:
1124     case VERIFY_16:
1125     case WRITE_16:
1126         cmd->xfer = buf[14] | (buf[13] << 8) | (buf[12] << 16);
1127         if (buf[1] & 0x01) { /* fixed */
1128             cmd->xfer *= dev->blocksize;
1129         }
1130         break;
1131     case REWIND:
1132     case LOAD_UNLOAD:
1133         cmd->xfer = 0;
1134         break;
1135     case SPACE_16:
1136         cmd->xfer = buf[13] | (buf[12] << 8);
1137         break;
1138     case READ_POSITION:
1139         switch (buf[1] & 0x1f) /* operation code */ {
1140         case SHORT_FORM_BLOCK_ID:
1141         case SHORT_FORM_VENDOR_SPECIFIC:
1142             cmd->xfer = 20;
1143             break;
1144         case LONG_FORM:
1145             cmd->xfer = 32;
1146             break;
1147         case EXTENDED_FORM:
1148             cmd->xfer = buf[8] | (buf[7] << 8);
1149             break;
1150         default:
1151             return -1;
1152         }
1153 
1154         break;
1155     case FORMAT_UNIT:
1156         cmd->xfer = buf[4] | (buf[3] << 8);
1157         break;
1158     /* generic commands */
1159     default:
1160         return scsi_req_xfer(cmd, dev, buf);
1161     }
1162     return 0;
1163 }
1164 
1165 static int scsi_req_medium_changer_xfer(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
1166 {
1167     switch (buf[0]) {
1168     /* medium changer commands */
1169     case EXCHANGE_MEDIUM:
1170     case INITIALIZE_ELEMENT_STATUS:
1171     case INITIALIZE_ELEMENT_STATUS_WITH_RANGE:
1172     case MOVE_MEDIUM:
1173     case POSITION_TO_ELEMENT:
1174         cmd->xfer = 0;
1175         break;
1176     case READ_ELEMENT_STATUS:
1177         cmd->xfer = buf[9] | (buf[8] << 8) | (buf[7] << 16);
1178         break;
1179 
1180     /* generic commands */
1181     default:
1182         return scsi_req_xfer(cmd, dev, buf);
1183     }
1184     return 0;
1185 }
1186 
1187 static int scsi_req_scanner_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
1188 {
1189     switch (buf[0]) {
1190     /* Scanner commands */
1191     case OBJECT_POSITION:
1192         cmd->xfer = 0;
1193         break;
1194     case SCAN:
1195         cmd->xfer = buf[4];
1196         break;
1197     case READ_10:
1198     case SEND:
1199     case GET_WINDOW:
1200     case SET_WINDOW:
1201         cmd->xfer = buf[8] | (buf[7] << 8) | (buf[6] << 16);
1202         break;
1203     default:
1204         /* GET_DATA_BUFFER_STATUS xfer handled by scsi_req_xfer */
1205         return scsi_req_xfer(cmd, dev, buf);
1206     }
1207 
1208     return 0;
1209 }
1210 
1211 static void scsi_cmd_xfer_mode(SCSICommand *cmd)
1212 {
1213     if (!cmd->xfer) {
1214         cmd->mode = SCSI_XFER_NONE;
1215         return;
1216     }
1217     switch (cmd->buf[0]) {
1218     case WRITE_6:
1219     case WRITE_10:
1220     case WRITE_VERIFY_10:
1221     case WRITE_12:
1222     case WRITE_VERIFY_12:
1223     case WRITE_16:
1224     case WRITE_VERIFY_16:
1225     case VERIFY_10:
1226     case VERIFY_12:
1227     case VERIFY_16:
1228     case COPY:
1229     case COPY_VERIFY:
1230     case COMPARE:
1231     case CHANGE_DEFINITION:
1232     case LOG_SELECT:
1233     case MODE_SELECT:
1234     case MODE_SELECT_10:
1235     case SEND_DIAGNOSTIC:
1236     case WRITE_BUFFER:
1237     case FORMAT_UNIT:
1238     case REASSIGN_BLOCKS:
1239     case SEARCH_EQUAL:
1240     case SEARCH_HIGH:
1241     case SEARCH_LOW:
1242     case UPDATE_BLOCK:
1243     case WRITE_LONG_10:
1244     case WRITE_SAME_10:
1245     case WRITE_SAME_16:
1246     case UNMAP:
1247     case SEARCH_HIGH_12:
1248     case SEARCH_EQUAL_12:
1249     case SEARCH_LOW_12:
1250     case MEDIUM_SCAN:
1251     case SEND_VOLUME_TAG:
1252     case SEND_CUE_SHEET:
1253     case SEND_DVD_STRUCTURE:
1254     case PERSISTENT_RESERVE_OUT:
1255     case MAINTENANCE_OUT:
1256     case SET_WINDOW:
1257     case SCAN:
1258         /* SCAN conflicts with START_STOP.  START_STOP has cmd->xfer set to 0 for
1259          * non-scanner devices, so we only get here for SCAN and not for START_STOP.
1260          */
1261         cmd->mode = SCSI_XFER_TO_DEV;
1262         break;
1263     case ATA_PASSTHROUGH_12:
1264     case ATA_PASSTHROUGH_16:
1265         /* T_DIR */
1266         cmd->mode = (cmd->buf[2] & 0x8) ?
1267                    SCSI_XFER_FROM_DEV : SCSI_XFER_TO_DEV;
1268         break;
1269     default:
1270         cmd->mode = SCSI_XFER_FROM_DEV;
1271         break;
1272     }
1273 }
1274 
1275 static uint64_t scsi_cmd_lba(SCSICommand *cmd)
1276 {
1277     uint8_t *buf = cmd->buf;
1278     uint64_t lba;
1279 
1280     switch (buf[0] >> 5) {
1281     case 0:
1282         lba = ldl_be_p(&buf[0]) & 0x1fffff;
1283         break;
1284     case 1:
1285     case 2:
1286     case 5:
1287         lba = ldl_be_p(&buf[2]) & 0xffffffffULL;
1288         break;
1289     case 4:
1290         lba = ldq_be_p(&buf[2]);
1291         break;
1292     default:
1293         lba = -1;
1294 
1295     }
1296     return lba;
1297 }
1298 
1299 int scsi_cdb_length(uint8_t *buf) {
1300     int cdb_len;
1301 
1302     switch (buf[0] >> 5) {
1303     case 0:
1304         cdb_len = 6;
1305         break;
1306     case 1:
1307     case 2:
1308         cdb_len = 10;
1309         break;
1310     case 4:
1311         cdb_len = 16;
1312         break;
1313     case 5:
1314         cdb_len = 12;
1315         break;
1316     default:
1317         cdb_len = -1;
1318     }
1319     return cdb_len;
1320 }
1321 
1322 int scsi_req_parse_cdb(SCSIDevice *dev, SCSICommand *cmd, uint8_t *buf)
1323 {
1324     int rc;
1325     int len;
1326 
1327     cmd->lba = -1;
1328     len = scsi_cdb_length(buf);
1329     if (len < 0) {
1330         return -1;
1331     }
1332 
1333     cmd->len = len;
1334     switch (dev->type) {
1335     case TYPE_TAPE:
1336         rc = scsi_req_stream_xfer(cmd, dev, buf);
1337         break;
1338     case TYPE_MEDIUM_CHANGER:
1339         rc = scsi_req_medium_changer_xfer(cmd, dev, buf);
1340         break;
1341     case TYPE_SCANNER:
1342         rc = scsi_req_scanner_length(cmd, dev, buf);
1343         break;
1344     default:
1345         rc = scsi_req_xfer(cmd, dev, buf);
1346         break;
1347     }
1348 
1349     if (rc != 0)
1350         return rc;
1351 
1352     memcpy(cmd->buf, buf, cmd->len);
1353     scsi_cmd_xfer_mode(cmd);
1354     cmd->lba = scsi_cmd_lba(cmd);
1355     return 0;
1356 }
1357 
1358 void scsi_device_report_change(SCSIDevice *dev, SCSISense sense)
1359 {
1360     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, dev->qdev.parent_bus);
1361 
1362     scsi_device_set_ua(dev, sense);
1363     if (bus->info->change) {
1364         bus->info->change(bus, dev, sense);
1365     }
1366 }
1367 
1368 /*
1369  * Predefined sense codes
1370  */
1371 
1372 /* No sense data available */
1373 const struct SCSISense sense_code_NO_SENSE = {
1374     .key = NO_SENSE , .asc = 0x00 , .ascq = 0x00
1375 };
1376 
1377 /* LUN not ready, Manual intervention required */
1378 const struct SCSISense sense_code_LUN_NOT_READY = {
1379     .key = NOT_READY, .asc = 0x04, .ascq = 0x03
1380 };
1381 
1382 /* LUN not ready, Medium not present */
1383 const struct SCSISense sense_code_NO_MEDIUM = {
1384     .key = NOT_READY, .asc = 0x3a, .ascq = 0x00
1385 };
1386 
1387 /* LUN not ready, medium removal prevented */
1388 const struct SCSISense sense_code_NOT_READY_REMOVAL_PREVENTED = {
1389     .key = NOT_READY, .asc = 0x53, .ascq = 0x02
1390 };
1391 
1392 /* Hardware error, internal target failure */
1393 const struct SCSISense sense_code_TARGET_FAILURE = {
1394     .key = HARDWARE_ERROR, .asc = 0x44, .ascq = 0x00
1395 };
1396 
1397 /* Illegal request, invalid command operation code */
1398 const struct SCSISense sense_code_INVALID_OPCODE = {
1399     .key = ILLEGAL_REQUEST, .asc = 0x20, .ascq = 0x00
1400 };
1401 
1402 /* Illegal request, LBA out of range */
1403 const struct SCSISense sense_code_LBA_OUT_OF_RANGE = {
1404     .key = ILLEGAL_REQUEST, .asc = 0x21, .ascq = 0x00
1405 };
1406 
1407 /* Illegal request, Invalid field in CDB */
1408 const struct SCSISense sense_code_INVALID_FIELD = {
1409     .key = ILLEGAL_REQUEST, .asc = 0x24, .ascq = 0x00
1410 };
1411 
1412 /* Illegal request, Invalid field in parameter list */
1413 const struct SCSISense sense_code_INVALID_PARAM = {
1414     .key = ILLEGAL_REQUEST, .asc = 0x26, .ascq = 0x00
1415 };
1416 
1417 /* Illegal request, Parameter list length error */
1418 const struct SCSISense sense_code_INVALID_PARAM_LEN = {
1419     .key = ILLEGAL_REQUEST, .asc = 0x1a, .ascq = 0x00
1420 };
1421 
1422 /* Illegal request, LUN not supported */
1423 const struct SCSISense sense_code_LUN_NOT_SUPPORTED = {
1424     .key = ILLEGAL_REQUEST, .asc = 0x25, .ascq = 0x00
1425 };
1426 
1427 /* Illegal request, Saving parameters not supported */
1428 const struct SCSISense sense_code_SAVING_PARAMS_NOT_SUPPORTED = {
1429     .key = ILLEGAL_REQUEST, .asc = 0x39, .ascq = 0x00
1430 };
1431 
1432 /* Illegal request, Incompatible medium installed */
1433 const struct SCSISense sense_code_INCOMPATIBLE_FORMAT = {
1434     .key = ILLEGAL_REQUEST, .asc = 0x30, .ascq = 0x00
1435 };
1436 
1437 /* Illegal request, medium removal prevented */
1438 const struct SCSISense sense_code_ILLEGAL_REQ_REMOVAL_PREVENTED = {
1439     .key = ILLEGAL_REQUEST, .asc = 0x53, .ascq = 0x02
1440 };
1441 
1442 /* Illegal request, Invalid Transfer Tag */
1443 const struct SCSISense sense_code_INVALID_TAG = {
1444     .key = ILLEGAL_REQUEST, .asc = 0x4b, .ascq = 0x01
1445 };
1446 
1447 /* Command aborted, I/O process terminated */
1448 const struct SCSISense sense_code_IO_ERROR = {
1449     .key = ABORTED_COMMAND, .asc = 0x00, .ascq = 0x06
1450 };
1451 
1452 /* Command aborted, I_T Nexus loss occurred */
1453 const struct SCSISense sense_code_I_T_NEXUS_LOSS = {
1454     .key = ABORTED_COMMAND, .asc = 0x29, .ascq = 0x07
1455 };
1456 
1457 /* Command aborted, Logical Unit failure */
1458 const struct SCSISense sense_code_LUN_FAILURE = {
1459     .key = ABORTED_COMMAND, .asc = 0x3e, .ascq = 0x01
1460 };
1461 
1462 /* Command aborted, Overlapped Commands Attempted */
1463 const struct SCSISense sense_code_OVERLAPPED_COMMANDS = {
1464     .key = ABORTED_COMMAND, .asc = 0x4e, .ascq = 0x00
1465 };
1466 
1467 /* Unit attention, Capacity data has changed */
1468 const struct SCSISense sense_code_CAPACITY_CHANGED = {
1469     .key = UNIT_ATTENTION, .asc = 0x2a, .ascq = 0x09
1470 };
1471 
1472 /* Unit attention, Power on, reset or bus device reset occurred */
1473 const struct SCSISense sense_code_RESET = {
1474     .key = UNIT_ATTENTION, .asc = 0x29, .ascq = 0x00
1475 };
1476 
1477 /* Unit attention, No medium */
1478 const struct SCSISense sense_code_UNIT_ATTENTION_NO_MEDIUM = {
1479     .key = UNIT_ATTENTION, .asc = 0x3a, .ascq = 0x00
1480 };
1481 
1482 /* Unit attention, Medium may have changed */
1483 const struct SCSISense sense_code_MEDIUM_CHANGED = {
1484     .key = UNIT_ATTENTION, .asc = 0x28, .ascq = 0x00
1485 };
1486 
1487 /* Unit attention, Reported LUNs data has changed */
1488 const struct SCSISense sense_code_REPORTED_LUNS_CHANGED = {
1489     .key = UNIT_ATTENTION, .asc = 0x3f, .ascq = 0x0e
1490 };
1491 
1492 /* Unit attention, Device internal reset */
1493 const struct SCSISense sense_code_DEVICE_INTERNAL_RESET = {
1494     .key = UNIT_ATTENTION, .asc = 0x29, .ascq = 0x04
1495 };
1496 
1497 /* Data Protection, Write Protected */
1498 const struct SCSISense sense_code_WRITE_PROTECTED = {
1499     .key = DATA_PROTECT, .asc = 0x27, .ascq = 0x00
1500 };
1501 
1502 /* Data Protection, Space Allocation Failed Write Protect */
1503 const struct SCSISense sense_code_SPACE_ALLOC_FAILED = {
1504     .key = DATA_PROTECT, .asc = 0x27, .ascq = 0x07
1505 };
1506 
1507 /*
1508  * scsi_build_sense
1509  *
1510  * Convert between fixed and descriptor sense buffers
1511  */
1512 int scsi_build_sense(uint8_t *in_buf, int in_len,
1513                      uint8_t *buf, int len, bool fixed)
1514 {
1515     bool fixed_in;
1516     SCSISense sense;
1517     if (!fixed && len < 8) {
1518         return 0;
1519     }
1520 
1521     if (in_len == 0) {
1522         sense.key = NO_SENSE;
1523         sense.asc = 0;
1524         sense.ascq = 0;
1525     } else {
1526         fixed_in = (in_buf[0] & 2) == 0;
1527 
1528         if (fixed == fixed_in) {
1529             memcpy(buf, in_buf, MIN(len, in_len));
1530             return MIN(len, in_len);
1531         }
1532 
1533         if (fixed_in) {
1534             sense.key = in_buf[2];
1535             sense.asc = in_buf[12];
1536             sense.ascq = in_buf[13];
1537         } else {
1538             sense.key = in_buf[1];
1539             sense.asc = in_buf[2];
1540             sense.ascq = in_buf[3];
1541         }
1542     }
1543 
1544     memset(buf, 0, len);
1545     if (fixed) {
1546         /* Return fixed format sense buffer */
1547         buf[0] = 0x70;
1548         buf[2] = sense.key;
1549         buf[7] = 10;
1550         buf[12] = sense.asc;
1551         buf[13] = sense.ascq;
1552         return MIN(len, SCSI_SENSE_LEN);
1553     } else {
1554         /* Return descriptor format sense buffer */
1555         buf[0] = 0x72;
1556         buf[1] = sense.key;
1557         buf[2] = sense.asc;
1558         buf[3] = sense.ascq;
1559         return 8;
1560     }
1561 }
1562 
1563 const char *scsi_command_name(uint8_t cmd)
1564 {
1565     static const char *names[] = {
1566         [ TEST_UNIT_READY          ] = "TEST_UNIT_READY",
1567         [ REWIND                   ] = "REWIND",
1568         [ REQUEST_SENSE            ] = "REQUEST_SENSE",
1569         [ FORMAT_UNIT              ] = "FORMAT_UNIT",
1570         [ READ_BLOCK_LIMITS        ] = "READ_BLOCK_LIMITS",
1571         [ REASSIGN_BLOCKS          ] = "REASSIGN_BLOCKS/INITIALIZE ELEMENT STATUS",
1572         /* LOAD_UNLOAD and INITIALIZE_ELEMENT_STATUS use the same operation code */
1573         [ READ_6                   ] = "READ_6",
1574         [ WRITE_6                  ] = "WRITE_6",
1575         [ SET_CAPACITY             ] = "SET_CAPACITY",
1576         [ READ_REVERSE             ] = "READ_REVERSE",
1577         [ WRITE_FILEMARKS          ] = "WRITE_FILEMARKS",
1578         [ SPACE                    ] = "SPACE",
1579         [ INQUIRY                  ] = "INQUIRY",
1580         [ RECOVER_BUFFERED_DATA    ] = "RECOVER_BUFFERED_DATA",
1581         [ MAINTENANCE_IN           ] = "MAINTENANCE_IN",
1582         [ MAINTENANCE_OUT          ] = "MAINTENANCE_OUT",
1583         [ MODE_SELECT              ] = "MODE_SELECT",
1584         [ RESERVE                  ] = "RESERVE",
1585         [ RELEASE                  ] = "RELEASE",
1586         [ COPY                     ] = "COPY",
1587         [ ERASE                    ] = "ERASE",
1588         [ MODE_SENSE               ] = "MODE_SENSE",
1589         [ START_STOP               ] = "START_STOP/LOAD_UNLOAD",
1590         /* LOAD_UNLOAD and START_STOP use the same operation code */
1591         [ RECEIVE_DIAGNOSTIC       ] = "RECEIVE_DIAGNOSTIC",
1592         [ SEND_DIAGNOSTIC          ] = "SEND_DIAGNOSTIC",
1593         [ ALLOW_MEDIUM_REMOVAL     ] = "ALLOW_MEDIUM_REMOVAL",
1594         [ READ_CAPACITY_10         ] = "READ_CAPACITY_10",
1595         [ READ_10                  ] = "READ_10",
1596         [ WRITE_10                 ] = "WRITE_10",
1597         [ SEEK_10                  ] = "SEEK_10/POSITION_TO_ELEMENT",
1598         /* SEEK_10 and POSITION_TO_ELEMENT use the same operation code */
1599         [ WRITE_VERIFY_10          ] = "WRITE_VERIFY_10",
1600         [ VERIFY_10                ] = "VERIFY_10",
1601         [ SEARCH_HIGH              ] = "SEARCH_HIGH",
1602         [ SEARCH_EQUAL             ] = "SEARCH_EQUAL",
1603         [ SEARCH_LOW               ] = "SEARCH_LOW",
1604         [ SET_LIMITS               ] = "SET_LIMITS",
1605         [ PRE_FETCH                ] = "PRE_FETCH/READ_POSITION",
1606         /* READ_POSITION and PRE_FETCH use the same operation code */
1607         [ SYNCHRONIZE_CACHE        ] = "SYNCHRONIZE_CACHE",
1608         [ LOCK_UNLOCK_CACHE        ] = "LOCK_UNLOCK_CACHE",
1609         [ READ_DEFECT_DATA         ] = "READ_DEFECT_DATA/INITIALIZE_ELEMENT_STATUS_WITH_RANGE",
1610         /* READ_DEFECT_DATA and INITIALIZE_ELEMENT_STATUS_WITH_RANGE use the same operation code */
1611         [ MEDIUM_SCAN              ] = "MEDIUM_SCAN",
1612         [ COMPARE                  ] = "COMPARE",
1613         [ COPY_VERIFY              ] = "COPY_VERIFY",
1614         [ WRITE_BUFFER             ] = "WRITE_BUFFER",
1615         [ READ_BUFFER              ] = "READ_BUFFER",
1616         [ UPDATE_BLOCK             ] = "UPDATE_BLOCK",
1617         [ READ_LONG_10             ] = "READ_LONG_10",
1618         [ WRITE_LONG_10            ] = "WRITE_LONG_10",
1619         [ CHANGE_DEFINITION        ] = "CHANGE_DEFINITION",
1620         [ WRITE_SAME_10            ] = "WRITE_SAME_10",
1621         [ UNMAP                    ] = "UNMAP",
1622         [ READ_TOC                 ] = "READ_TOC",
1623         [ REPORT_DENSITY_SUPPORT   ] = "REPORT_DENSITY_SUPPORT",
1624         [ SANITIZE                 ] = "SANITIZE",
1625         [ GET_CONFIGURATION        ] = "GET_CONFIGURATION",
1626         [ LOG_SELECT               ] = "LOG_SELECT",
1627         [ LOG_SENSE                ] = "LOG_SENSE",
1628         [ MODE_SELECT_10           ] = "MODE_SELECT_10",
1629         [ RESERVE_10               ] = "RESERVE_10",
1630         [ RELEASE_10               ] = "RELEASE_10",
1631         [ MODE_SENSE_10            ] = "MODE_SENSE_10",
1632         [ PERSISTENT_RESERVE_IN    ] = "PERSISTENT_RESERVE_IN",
1633         [ PERSISTENT_RESERVE_OUT   ] = "PERSISTENT_RESERVE_OUT",
1634         [ WRITE_FILEMARKS_16       ] = "WRITE_FILEMARKS_16",
1635         [ EXTENDED_COPY            ] = "EXTENDED_COPY",
1636         [ ATA_PASSTHROUGH_16       ] = "ATA_PASSTHROUGH_16",
1637         [ ACCESS_CONTROL_IN        ] = "ACCESS_CONTROL_IN",
1638         [ ACCESS_CONTROL_OUT       ] = "ACCESS_CONTROL_OUT",
1639         [ READ_16                  ] = "READ_16",
1640         [ COMPARE_AND_WRITE        ] = "COMPARE_AND_WRITE",
1641         [ WRITE_16                 ] = "WRITE_16",
1642         [ WRITE_VERIFY_16          ] = "WRITE_VERIFY_16",
1643         [ VERIFY_16                ] = "VERIFY_16",
1644         [ PRE_FETCH_16             ] = "PRE_FETCH_16",
1645         [ SYNCHRONIZE_CACHE_16     ] = "SPACE_16/SYNCHRONIZE_CACHE_16",
1646         /* SPACE_16 and SYNCHRONIZE_CACHE_16 use the same operation code */
1647         [ LOCATE_16                ] = "LOCATE_16",
1648         [ WRITE_SAME_16            ] = "ERASE_16/WRITE_SAME_16",
1649         /* ERASE_16 and WRITE_SAME_16 use the same operation code */
1650         [ SERVICE_ACTION_IN_16     ] = "SERVICE_ACTION_IN_16",
1651         [ WRITE_LONG_16            ] = "WRITE_LONG_16",
1652         [ REPORT_LUNS              ] = "REPORT_LUNS",
1653         [ ATA_PASSTHROUGH_12       ] = "BLANK/ATA_PASSTHROUGH_12",
1654         [ MOVE_MEDIUM              ] = "MOVE_MEDIUM",
1655         [ EXCHANGE_MEDIUM          ] = "EXCHANGE MEDIUM",
1656         [ READ_12                  ] = "READ_12",
1657         [ WRITE_12                 ] = "WRITE_12",
1658         [ ERASE_12                 ] = "ERASE_12/GET_PERFORMANCE",
1659         /* ERASE_12 and GET_PERFORMANCE use the same operation code */
1660         [ SERVICE_ACTION_IN_12     ] = "SERVICE_ACTION_IN_12",
1661         [ WRITE_VERIFY_12          ] = "WRITE_VERIFY_12",
1662         [ VERIFY_12                ] = "VERIFY_12",
1663         [ SEARCH_HIGH_12           ] = "SEARCH_HIGH_12",
1664         [ SEARCH_EQUAL_12          ] = "SEARCH_EQUAL_12",
1665         [ SEARCH_LOW_12            ] = "SEARCH_LOW_12",
1666         [ READ_ELEMENT_STATUS      ] = "READ_ELEMENT_STATUS",
1667         [ SEND_VOLUME_TAG          ] = "SEND_VOLUME_TAG/SET_STREAMING",
1668         /* SEND_VOLUME_TAG and SET_STREAMING use the same operation code */
1669         [ READ_CD                  ] = "READ_CD",
1670         [ READ_DEFECT_DATA_12      ] = "READ_DEFECT_DATA_12",
1671         [ READ_DVD_STRUCTURE       ] = "READ_DVD_STRUCTURE",
1672         [ RESERVE_TRACK            ] = "RESERVE_TRACK",
1673         [ SEND_CUE_SHEET           ] = "SEND_CUE_SHEET",
1674         [ SEND_DVD_STRUCTURE       ] = "SEND_DVD_STRUCTURE",
1675         [ SET_CD_SPEED             ] = "SET_CD_SPEED",
1676         [ SET_READ_AHEAD           ] = "SET_READ_AHEAD",
1677         [ ALLOW_OVERWRITE          ] = "ALLOW_OVERWRITE",
1678         [ MECHANISM_STATUS         ] = "MECHANISM_STATUS",
1679         [ GET_EVENT_STATUS_NOTIFICATION ] = "GET_EVENT_STATUS_NOTIFICATION",
1680         [ READ_DISC_INFORMATION    ] = "READ_DISC_INFORMATION",
1681     };
1682 
1683     if (cmd >= ARRAY_SIZE(names) || names[cmd] == NULL)
1684         return "*UNKNOWN*";
1685     return names[cmd];
1686 }
1687 
1688 SCSIRequest *scsi_req_ref(SCSIRequest *req)
1689 {
1690     assert(req->refcount > 0);
1691     req->refcount++;
1692     return req;
1693 }
1694 
1695 void scsi_req_unref(SCSIRequest *req)
1696 {
1697     assert(req->refcount > 0);
1698     if (--req->refcount == 0) {
1699         BusState *qbus = req->dev->qdev.parent_bus;
1700         SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, qbus);
1701 
1702         if (bus->info->free_request && req->hba_private) {
1703             bus->info->free_request(bus, req->hba_private);
1704         }
1705         if (req->ops->free_req) {
1706             req->ops->free_req(req);
1707         }
1708         object_unref(OBJECT(req->dev));
1709         object_unref(OBJECT(qbus->parent));
1710         g_free(req);
1711     }
1712 }
1713 
1714 /* Tell the device that we finished processing this chunk of I/O.  It
1715    will start the next chunk or complete the command.  */
1716 void scsi_req_continue(SCSIRequest *req)
1717 {
1718     if (req->io_canceled) {
1719         trace_scsi_req_continue_canceled(req->dev->id, req->lun, req->tag);
1720         return;
1721     }
1722     trace_scsi_req_continue(req->dev->id, req->lun, req->tag);
1723     if (req->cmd.mode == SCSI_XFER_TO_DEV) {
1724         req->ops->write_data(req);
1725     } else {
1726         req->ops->read_data(req);
1727     }
1728 }
1729 
1730 /* Called by the devices when data is ready for the HBA.  The HBA should
1731    start a DMA operation to read or fill the device's data buffer.
1732    Once it completes, calling scsi_req_continue will restart I/O.  */
1733 void scsi_req_data(SCSIRequest *req, int len)
1734 {
1735     uint8_t *buf;
1736     if (req->io_canceled) {
1737         trace_scsi_req_data_canceled(req->dev->id, req->lun, req->tag, len);
1738         return;
1739     }
1740     trace_scsi_req_data(req->dev->id, req->lun, req->tag, len);
1741     assert(req->cmd.mode != SCSI_XFER_NONE);
1742     if (!req->sg) {
1743         req->resid -= len;
1744         req->bus->info->transfer_data(req, len);
1745         return;
1746     }
1747 
1748     /* If the device calls scsi_req_data and the HBA specified a
1749      * scatter/gather list, the transfer has to happen in a single
1750      * step.  */
1751     assert(!req->dma_started);
1752     req->dma_started = true;
1753 
1754     buf = scsi_req_get_buf(req);
1755     if (req->cmd.mode == SCSI_XFER_FROM_DEV) {
1756         req->resid = dma_buf_read(buf, len, req->sg);
1757     } else {
1758         req->resid = dma_buf_write(buf, len, req->sg);
1759     }
1760     scsi_req_continue(req);
1761 }
1762 
1763 void scsi_req_print(SCSIRequest *req)
1764 {
1765     FILE *fp = stderr;
1766     int i;
1767 
1768     fprintf(fp, "[%s id=%d] %s",
1769             req->dev->qdev.parent_bus->name,
1770             req->dev->id,
1771             scsi_command_name(req->cmd.buf[0]));
1772     for (i = 1; i < req->cmd.len; i++) {
1773         fprintf(fp, " 0x%02x", req->cmd.buf[i]);
1774     }
1775     switch (req->cmd.mode) {
1776     case SCSI_XFER_NONE:
1777         fprintf(fp, " - none\n");
1778         break;
1779     case SCSI_XFER_FROM_DEV:
1780         fprintf(fp, " - from-dev len=%zd\n", req->cmd.xfer);
1781         break;
1782     case SCSI_XFER_TO_DEV:
1783         fprintf(fp, " - to-dev len=%zd\n", req->cmd.xfer);
1784         break;
1785     default:
1786         fprintf(fp, " - Oops\n");
1787         break;
1788     }
1789 }
1790 
1791 void scsi_req_complete(SCSIRequest *req, int status)
1792 {
1793     assert(req->status == -1);
1794     req->status = status;
1795 
1796     assert(req->sense_len <= sizeof(req->sense));
1797     if (status == GOOD) {
1798         req->sense_len = 0;
1799     }
1800 
1801     if (req->sense_len) {
1802         memcpy(req->dev->sense, req->sense, req->sense_len);
1803         req->dev->sense_len = req->sense_len;
1804         req->dev->sense_is_ua = (req->ops == &reqops_unit_attention);
1805     } else {
1806         req->dev->sense_len = 0;
1807         req->dev->sense_is_ua = false;
1808     }
1809 
1810     /*
1811      * Unit attention state is now stored in the device's sense buffer
1812      * if the HBA didn't do autosense.  Clear the pending unit attention
1813      * flags.
1814      */
1815     scsi_clear_unit_attention(req);
1816 
1817     scsi_req_ref(req);
1818     scsi_req_dequeue(req);
1819     req->bus->info->complete(req, req->status, req->resid);
1820 
1821     /* Cancelled requests might end up being completed instead of cancelled */
1822     notifier_list_notify(&req->cancel_notifiers, req);
1823     scsi_req_unref(req);
1824 }
1825 
1826 /* Called by the devices when the request is canceled. */
1827 void scsi_req_cancel_complete(SCSIRequest *req)
1828 {
1829     assert(req->io_canceled);
1830     if (req->bus->info->cancel) {
1831         req->bus->info->cancel(req);
1832     }
1833     notifier_list_notify(&req->cancel_notifiers, req);
1834     scsi_req_unref(req);
1835 }
1836 
1837 /* Cancel @req asynchronously. @notifier is added to @req's cancellation
1838  * notifier list, the bus will be notified the requests cancellation is
1839  * completed.
1840  * */
1841 void scsi_req_cancel_async(SCSIRequest *req, Notifier *notifier)
1842 {
1843     trace_scsi_req_cancel(req->dev->id, req->lun, req->tag);
1844     if (notifier) {
1845         notifier_list_add(&req->cancel_notifiers, notifier);
1846     }
1847     if (req->io_canceled) {
1848         /* A blk_aio_cancel_async is pending; when it finishes,
1849          * scsi_req_cancel_complete will be called and will
1850          * call the notifier we just added.  Just wait for that.
1851          */
1852         assert(req->aiocb);
1853         return;
1854     }
1855     /* Dropped in scsi_req_cancel_complete.  */
1856     scsi_req_ref(req);
1857     scsi_req_dequeue(req);
1858     req->io_canceled = true;
1859     if (req->aiocb) {
1860         blk_aio_cancel_async(req->aiocb);
1861     } else {
1862         scsi_req_cancel_complete(req);
1863     }
1864 }
1865 
1866 void scsi_req_cancel(SCSIRequest *req)
1867 {
1868     trace_scsi_req_cancel(req->dev->id, req->lun, req->tag);
1869     if (!req->enqueued) {
1870         return;
1871     }
1872     assert(!req->io_canceled);
1873     /* Dropped in scsi_req_cancel_complete.  */
1874     scsi_req_ref(req);
1875     scsi_req_dequeue(req);
1876     req->io_canceled = true;
1877     if (req->aiocb) {
1878         blk_aio_cancel(req->aiocb);
1879     } else {
1880         scsi_req_cancel_complete(req);
1881     }
1882 }
1883 
1884 static int scsi_ua_precedence(SCSISense sense)
1885 {
1886     if (sense.key != UNIT_ATTENTION) {
1887         return INT_MAX;
1888     }
1889     if (sense.asc == 0x29 && sense.ascq == 0x04) {
1890         /* DEVICE INTERNAL RESET goes with POWER ON OCCURRED */
1891         return 1;
1892     } else if (sense.asc == 0x3F && sense.ascq == 0x01) {
1893         /* MICROCODE HAS BEEN CHANGED goes with SCSI BUS RESET OCCURRED */
1894         return 2;
1895     } else if (sense.asc == 0x29 && (sense.ascq == 0x05 || sense.ascq == 0x06)) {
1896         /* These two go with "all others". */
1897         ;
1898     } else if (sense.asc == 0x29 && sense.ascq <= 0x07) {
1899         /* POWER ON, RESET OR BUS DEVICE RESET OCCURRED = 0
1900          * POWER ON OCCURRED = 1
1901          * SCSI BUS RESET OCCURRED = 2
1902          * BUS DEVICE RESET FUNCTION OCCURRED = 3
1903          * I_T NEXUS LOSS OCCURRED = 7
1904          */
1905         return sense.ascq;
1906     } else if (sense.asc == 0x2F && sense.ascq == 0x01) {
1907         /* COMMANDS CLEARED BY POWER LOSS NOTIFICATION  */
1908         return 8;
1909     }
1910     return (sense.asc << 8) | sense.ascq;
1911 }
1912 
1913 void scsi_device_set_ua(SCSIDevice *sdev, SCSISense sense)
1914 {
1915     int prec1, prec2;
1916     if (sense.key != UNIT_ATTENTION) {
1917         return;
1918     }
1919     trace_scsi_device_set_ua(sdev->id, sdev->lun, sense.key,
1920                              sense.asc, sense.ascq);
1921 
1922     /*
1923      * Override a pre-existing unit attention condition, except for a more
1924      * important reset condition.
1925     */
1926     prec1 = scsi_ua_precedence(sdev->unit_attention);
1927     prec2 = scsi_ua_precedence(sense);
1928     if (prec2 < prec1) {
1929         sdev->unit_attention = sense;
1930     }
1931 }
1932 
1933 void scsi_device_purge_requests(SCSIDevice *sdev, SCSISense sense)
1934 {
1935     SCSIRequest *req;
1936 
1937     aio_context_acquire(blk_get_aio_context(sdev->conf.blk));
1938     while (!QTAILQ_EMPTY(&sdev->requests)) {
1939         req = QTAILQ_FIRST(&sdev->requests);
1940         scsi_req_cancel_async(req, NULL);
1941     }
1942     blk_drain(sdev->conf.blk);
1943     aio_context_release(blk_get_aio_context(sdev->conf.blk));
1944     scsi_device_set_ua(sdev, sense);
1945 }
1946 
1947 static char *scsibus_get_dev_path(DeviceState *dev)
1948 {
1949     SCSIDevice *d = SCSI_DEVICE(dev);
1950     DeviceState *hba = dev->parent_bus->parent;
1951     char *id;
1952     char *path;
1953 
1954     id = qdev_get_dev_path(hba);
1955     if (id) {
1956         path = g_strdup_printf("%s/%d:%d:%d", id, d->channel, d->id, d->lun);
1957     } else {
1958         path = g_strdup_printf("%d:%d:%d", d->channel, d->id, d->lun);
1959     }
1960     g_free(id);
1961     return path;
1962 }
1963 
1964 static char *scsibus_get_fw_dev_path(DeviceState *dev)
1965 {
1966     SCSIDevice *d = SCSI_DEVICE(dev);
1967     return g_strdup_printf("channel@%x/%s@%x,%x", d->channel,
1968                            qdev_fw_name(dev), d->id, d->lun);
1969 }
1970 
1971 SCSIDevice *scsi_device_find(SCSIBus *bus, int channel, int id, int lun)
1972 {
1973     BusChild *kid;
1974     SCSIDevice *target_dev = NULL;
1975 
1976     QTAILQ_FOREACH_REVERSE(kid, &bus->qbus.children, ChildrenHead, sibling) {
1977         DeviceState *qdev = kid->child;
1978         SCSIDevice *dev = SCSI_DEVICE(qdev);
1979 
1980         if (dev->channel == channel && dev->id == id) {
1981             if (dev->lun == lun) {
1982                 return dev;
1983             }
1984             target_dev = dev;
1985         }
1986     }
1987     return target_dev;
1988 }
1989 
1990 /* SCSI request list.  For simplicity, pv points to the whole device */
1991 
1992 static int put_scsi_requests(QEMUFile *f, void *pv, size_t size,
1993                              VMStateField *field, QJSON *vmdesc)
1994 {
1995     SCSIDevice *s = pv;
1996     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, s->qdev.parent_bus);
1997     SCSIRequest *req;
1998 
1999     QTAILQ_FOREACH(req, &s->requests, next) {
2000         assert(!req->io_canceled);
2001         assert(req->status == -1);
2002         assert(req->enqueued);
2003 
2004         qemu_put_sbyte(f, req->retry ? 1 : 2);
2005         qemu_put_buffer(f, req->cmd.buf, sizeof(req->cmd.buf));
2006         qemu_put_be32s(f, &req->tag);
2007         qemu_put_be32s(f, &req->lun);
2008         if (bus->info->save_request) {
2009             bus->info->save_request(f, req);
2010         }
2011         if (req->ops->save_request) {
2012             req->ops->save_request(f, req);
2013         }
2014     }
2015     qemu_put_sbyte(f, 0);
2016 
2017     return 0;
2018 }
2019 
2020 static int get_scsi_requests(QEMUFile *f, void *pv, size_t size,
2021                              VMStateField *field)
2022 {
2023     SCSIDevice *s = pv;
2024     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, s->qdev.parent_bus);
2025     int8_t sbyte;
2026 
2027     while ((sbyte = qemu_get_sbyte(f)) > 0) {
2028         uint8_t buf[SCSI_CMD_BUF_SIZE];
2029         uint32_t tag;
2030         uint32_t lun;
2031         SCSIRequest *req;
2032 
2033         qemu_get_buffer(f, buf, sizeof(buf));
2034         qemu_get_be32s(f, &tag);
2035         qemu_get_be32s(f, &lun);
2036         req = scsi_req_new(s, tag, lun, buf, NULL);
2037         req->retry = (sbyte == 1);
2038         if (bus->info->load_request) {
2039             req->hba_private = bus->info->load_request(f, req);
2040         }
2041         if (req->ops->load_request) {
2042             req->ops->load_request(f, req);
2043         }
2044 
2045         /* Just restart it later.  */
2046         scsi_req_enqueue_internal(req);
2047 
2048         /* At this point, the request will be kept alive by the reference
2049          * added by scsi_req_enqueue_internal, so we can release our reference.
2050          * The HBA of course will add its own reference in the load_request
2051          * callback if it needs to hold on the SCSIRequest.
2052          */
2053         scsi_req_unref(req);
2054     }
2055 
2056     return 0;
2057 }
2058 
2059 static const VMStateInfo vmstate_info_scsi_requests = {
2060     .name = "scsi-requests",
2061     .get  = get_scsi_requests,
2062     .put  = put_scsi_requests,
2063 };
2064 
2065 static bool scsi_sense_state_needed(void *opaque)
2066 {
2067     SCSIDevice *s = opaque;
2068 
2069     return s->sense_len > SCSI_SENSE_BUF_SIZE_OLD;
2070 }
2071 
2072 static const VMStateDescription vmstate_scsi_sense_state = {
2073     .name = "SCSIDevice/sense",
2074     .version_id = 1,
2075     .minimum_version_id = 1,
2076     .needed = scsi_sense_state_needed,
2077     .fields = (VMStateField[]) {
2078         VMSTATE_UINT8_SUB_ARRAY(sense, SCSIDevice,
2079                                 SCSI_SENSE_BUF_SIZE_OLD,
2080                                 SCSI_SENSE_BUF_SIZE - SCSI_SENSE_BUF_SIZE_OLD),
2081         VMSTATE_END_OF_LIST()
2082     }
2083 };
2084 
2085 const VMStateDescription vmstate_scsi_device = {
2086     .name = "SCSIDevice",
2087     .version_id = 1,
2088     .minimum_version_id = 1,
2089     .fields = (VMStateField[]) {
2090         VMSTATE_UINT8(unit_attention.key, SCSIDevice),
2091         VMSTATE_UINT8(unit_attention.asc, SCSIDevice),
2092         VMSTATE_UINT8(unit_attention.ascq, SCSIDevice),
2093         VMSTATE_BOOL(sense_is_ua, SCSIDevice),
2094         VMSTATE_UINT8_SUB_ARRAY(sense, SCSIDevice, 0, SCSI_SENSE_BUF_SIZE_OLD),
2095         VMSTATE_UINT32(sense_len, SCSIDevice),
2096         {
2097             .name         = "requests",
2098             .version_id   = 0,
2099             .field_exists = NULL,
2100             .size         = 0,   /* ouch */
2101             .info         = &vmstate_info_scsi_requests,
2102             .flags        = VMS_SINGLE,
2103             .offset       = 0,
2104         },
2105         VMSTATE_END_OF_LIST()
2106     },
2107     .subsections = (const VMStateDescription*[]) {
2108         &vmstate_scsi_sense_state,
2109         NULL
2110     }
2111 };
2112 
2113 static void scsi_device_class_init(ObjectClass *klass, void *data)
2114 {
2115     DeviceClass *k = DEVICE_CLASS(klass);
2116     set_bit(DEVICE_CATEGORY_STORAGE, k->categories);
2117     k->bus_type  = TYPE_SCSI_BUS;
2118     k->realize   = scsi_qdev_realize;
2119     k->unrealize = scsi_qdev_unrealize;
2120     k->props     = scsi_props;
2121 }
2122 
2123 static void scsi_dev_instance_init(Object *obj)
2124 {
2125     DeviceState *dev = DEVICE(obj);
2126     SCSIDevice *s = SCSI_DEVICE(dev);
2127 
2128     device_add_bootindex_property(obj, &s->conf.bootindex,
2129                                   "bootindex", NULL,
2130                                   &s->qdev, NULL);
2131 }
2132 
2133 static const TypeInfo scsi_device_type_info = {
2134     .name = TYPE_SCSI_DEVICE,
2135     .parent = TYPE_DEVICE,
2136     .instance_size = sizeof(SCSIDevice),
2137     .abstract = true,
2138     .class_size = sizeof(SCSIDeviceClass),
2139     .class_init = scsi_device_class_init,
2140     .instance_init = scsi_dev_instance_init,
2141 };
2142 
2143 static void scsi_register_types(void)
2144 {
2145     type_register_static(&scsi_bus_info);
2146     type_register_static(&scsi_device_type_info);
2147 }
2148 
2149 type_init(scsi_register_types)
2150