xref: /openbmc/qemu/hw/scsi/scsi-bus.c (revision 6a0acfff)
1 #include "qemu/osdep.h"
2 #include "hw/hw.h"
3 #include "qapi/error.h"
4 #include "qemu/error-report.h"
5 #include "qemu/module.h"
6 #include "qemu/option.h"
7 #include "hw/scsi/scsi.h"
8 #include "migration/qemu-file-types.h"
9 #include "scsi/constants.h"
10 #include "hw/qdev.h"
11 #include "sysemu/block-backend.h"
12 #include "sysemu/blockdev.h"
13 #include "trace.h"
14 #include "sysemu/dma.h"
15 #include "qemu/cutils.h"
16 
17 static char *scsibus_get_dev_path(DeviceState *dev);
18 static char *scsibus_get_fw_dev_path(DeviceState *dev);
19 static void scsi_req_dequeue(SCSIRequest *req);
20 static uint8_t *scsi_target_alloc_buf(SCSIRequest *req, size_t len);
21 static void scsi_target_free_buf(SCSIRequest *req);
22 
23 static Property scsi_props[] = {
24     DEFINE_PROP_UINT32("channel", SCSIDevice, channel, 0),
25     DEFINE_PROP_UINT32("scsi-id", SCSIDevice, id, -1),
26     DEFINE_PROP_UINT32("lun", SCSIDevice, lun, -1),
27     DEFINE_PROP_END_OF_LIST(),
28 };
29 
30 static void scsi_bus_class_init(ObjectClass *klass, void *data)
31 {
32     BusClass *k = BUS_CLASS(klass);
33     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
34 
35     k->get_dev_path = scsibus_get_dev_path;
36     k->get_fw_dev_path = scsibus_get_fw_dev_path;
37     hc->unplug = qdev_simple_device_unplug_cb;
38 }
39 
40 static const TypeInfo scsi_bus_info = {
41     .name = TYPE_SCSI_BUS,
42     .parent = TYPE_BUS,
43     .instance_size = sizeof(SCSIBus),
44     .class_init = scsi_bus_class_init,
45     .interfaces = (InterfaceInfo[]) {
46         { TYPE_HOTPLUG_HANDLER },
47         { }
48     }
49 };
50 static int next_scsi_bus;
51 
52 static void scsi_device_realize(SCSIDevice *s, Error **errp)
53 {
54     SCSIDeviceClass *sc = SCSI_DEVICE_GET_CLASS(s);
55     if (sc->realize) {
56         sc->realize(s, errp);
57     }
58 }
59 
60 int scsi_bus_parse_cdb(SCSIDevice *dev, SCSICommand *cmd, uint8_t *buf,
61                        void *hba_private)
62 {
63     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, dev->qdev.parent_bus);
64     int rc;
65 
66     assert(cmd->len == 0);
67     rc = scsi_req_parse_cdb(dev, cmd, buf);
68     if (bus->info->parse_cdb) {
69         rc = bus->info->parse_cdb(dev, cmd, buf, hba_private);
70     }
71     return rc;
72 }
73 
74 static SCSIRequest *scsi_device_alloc_req(SCSIDevice *s, uint32_t tag, uint32_t lun,
75                                           uint8_t *buf, void *hba_private)
76 {
77     SCSIDeviceClass *sc = SCSI_DEVICE_GET_CLASS(s);
78     if (sc->alloc_req) {
79         return sc->alloc_req(s, tag, lun, buf, hba_private);
80     }
81 
82     return NULL;
83 }
84 
85 void scsi_device_unit_attention_reported(SCSIDevice *s)
86 {
87     SCSIDeviceClass *sc = SCSI_DEVICE_GET_CLASS(s);
88     if (sc->unit_attention_reported) {
89         sc->unit_attention_reported(s);
90     }
91 }
92 
93 /* Create a scsi bus, and attach devices to it.  */
94 void scsi_bus_new(SCSIBus *bus, size_t bus_size, DeviceState *host,
95                   const SCSIBusInfo *info, const char *bus_name)
96 {
97     qbus_create_inplace(bus, bus_size, TYPE_SCSI_BUS, host, bus_name);
98     bus->busnr = next_scsi_bus++;
99     bus->info = info;
100     qbus_set_bus_hotplug_handler(BUS(bus), &error_abort);
101 }
102 
103 static void scsi_dma_restart_bh(void *opaque)
104 {
105     SCSIDevice *s = opaque;
106     SCSIRequest *req, *next;
107 
108     qemu_bh_delete(s->bh);
109     s->bh = NULL;
110 
111     aio_context_acquire(blk_get_aio_context(s->conf.blk));
112     QTAILQ_FOREACH_SAFE(req, &s->requests, next, next) {
113         scsi_req_ref(req);
114         if (req->retry) {
115             req->retry = false;
116             switch (req->cmd.mode) {
117             case SCSI_XFER_FROM_DEV:
118             case SCSI_XFER_TO_DEV:
119                 scsi_req_continue(req);
120                 break;
121             case SCSI_XFER_NONE:
122                 scsi_req_dequeue(req);
123                 scsi_req_enqueue(req);
124                 break;
125             }
126         }
127         scsi_req_unref(req);
128     }
129     aio_context_release(blk_get_aio_context(s->conf.blk));
130 }
131 
132 void scsi_req_retry(SCSIRequest *req)
133 {
134     /* No need to save a reference, because scsi_dma_restart_bh just
135      * looks at the request list.  */
136     req->retry = true;
137 }
138 
139 static void scsi_dma_restart_cb(void *opaque, int running, RunState state)
140 {
141     SCSIDevice *s = opaque;
142 
143     if (!running) {
144         return;
145     }
146     if (!s->bh) {
147         AioContext *ctx = blk_get_aio_context(s->conf.blk);
148         s->bh = aio_bh_new(ctx, scsi_dma_restart_bh, s);
149         qemu_bh_schedule(s->bh);
150     }
151 }
152 
153 static void scsi_qdev_realize(DeviceState *qdev, Error **errp)
154 {
155     SCSIDevice *dev = SCSI_DEVICE(qdev);
156     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, dev->qdev.parent_bus);
157     SCSIDevice *d;
158     Error *local_err = NULL;
159 
160     if (dev->channel > bus->info->max_channel) {
161         error_setg(errp, "bad scsi channel id: %d", dev->channel);
162         return;
163     }
164     if (dev->id != -1 && dev->id > bus->info->max_target) {
165         error_setg(errp, "bad scsi device id: %d", dev->id);
166         return;
167     }
168     if (dev->lun != -1 && dev->lun > bus->info->max_lun) {
169         error_setg(errp, "bad scsi device lun: %d", dev->lun);
170         return;
171     }
172 
173     if (dev->id == -1) {
174         int id = -1;
175         if (dev->lun == -1) {
176             dev->lun = 0;
177         }
178         do {
179             d = scsi_device_find(bus, dev->channel, ++id, dev->lun);
180         } while (d && d->lun == dev->lun && id < bus->info->max_target);
181         if (d && d->lun == dev->lun) {
182             error_setg(errp, "no free target");
183             return;
184         }
185         dev->id = id;
186     } else if (dev->lun == -1) {
187         int lun = -1;
188         do {
189             d = scsi_device_find(bus, dev->channel, dev->id, ++lun);
190         } while (d && d->lun == lun && lun < bus->info->max_lun);
191         if (d && d->lun == lun) {
192             error_setg(errp, "no free lun");
193             return;
194         }
195         dev->lun = lun;
196     } else {
197         d = scsi_device_find(bus, dev->channel, dev->id, dev->lun);
198         assert(d);
199         if (d->lun == dev->lun && dev != d) {
200             error_setg(errp, "lun already used by '%s'", d->qdev.id);
201             return;
202         }
203     }
204 
205     QTAILQ_INIT(&dev->requests);
206     scsi_device_realize(dev, &local_err);
207     if (local_err) {
208         error_propagate(errp, local_err);
209         return;
210     }
211     dev->vmsentry = qdev_add_vm_change_state_handler(DEVICE(dev),
212             scsi_dma_restart_cb, dev);
213 }
214 
215 static void scsi_qdev_unrealize(DeviceState *qdev, Error **errp)
216 {
217     SCSIDevice *dev = SCSI_DEVICE(qdev);
218 
219     if (dev->vmsentry) {
220         qemu_del_vm_change_state_handler(dev->vmsentry);
221     }
222 
223     scsi_device_purge_requests(dev, SENSE_CODE(NO_SENSE));
224     blockdev_mark_auto_del(dev->conf.blk);
225 }
226 
227 /* handle legacy '-drive if=scsi,...' cmd line args */
228 SCSIDevice *scsi_bus_legacy_add_drive(SCSIBus *bus, BlockBackend *blk,
229                                       int unit, bool removable, int bootindex,
230                                       bool share_rw,
231                                       BlockdevOnError rerror,
232                                       BlockdevOnError werror,
233                                       const char *serial, Error **errp)
234 {
235     const char *driver;
236     char *name;
237     DeviceState *dev;
238     Error *err = NULL;
239 
240     driver = blk_is_sg(blk) ? "scsi-generic" : "scsi-disk";
241     dev = qdev_create(&bus->qbus, driver);
242     name = g_strdup_printf("legacy[%d]", unit);
243     object_property_add_child(OBJECT(bus), name, OBJECT(dev), NULL);
244     g_free(name);
245 
246     qdev_prop_set_uint32(dev, "scsi-id", unit);
247     if (bootindex >= 0) {
248         object_property_set_int(OBJECT(dev), bootindex, "bootindex",
249                                 &error_abort);
250     }
251     if (object_property_find(OBJECT(dev), "removable", NULL)) {
252         qdev_prop_set_bit(dev, "removable", removable);
253     }
254     if (serial && object_property_find(OBJECT(dev), "serial", NULL)) {
255         qdev_prop_set_string(dev, "serial", serial);
256     }
257     qdev_prop_set_drive(dev, "drive", blk, &err);
258     if (err) {
259         error_propagate(errp, err);
260         object_unparent(OBJECT(dev));
261         return NULL;
262     }
263     object_property_set_bool(OBJECT(dev), share_rw, "share-rw", &err);
264     if (err != NULL) {
265         error_propagate(errp, err);
266         object_unparent(OBJECT(dev));
267         return NULL;
268     }
269 
270     qdev_prop_set_enum(dev, "rerror", rerror);
271     qdev_prop_set_enum(dev, "werror", werror);
272 
273     object_property_set_bool(OBJECT(dev), true, "realized", &err);
274     if (err != NULL) {
275         error_propagate(errp, err);
276         object_unparent(OBJECT(dev));
277         return NULL;
278     }
279     return SCSI_DEVICE(dev);
280 }
281 
282 void scsi_bus_legacy_handle_cmdline(SCSIBus *bus)
283 {
284     Location loc;
285     DriveInfo *dinfo;
286     int unit;
287 
288     loc_push_none(&loc);
289     for (unit = 0; unit <= bus->info->max_target; unit++) {
290         dinfo = drive_get(IF_SCSI, bus->busnr, unit);
291         if (dinfo == NULL) {
292             continue;
293         }
294         qemu_opts_loc_restore(dinfo->opts);
295         scsi_bus_legacy_add_drive(bus, blk_by_legacy_dinfo(dinfo),
296                                   unit, false, -1, false,
297                                   BLOCKDEV_ON_ERROR_AUTO,
298                                   BLOCKDEV_ON_ERROR_AUTO,
299                                   NULL, &error_fatal);
300     }
301     loc_pop(&loc);
302 }
303 
304 static int32_t scsi_invalid_field(SCSIRequest *req, uint8_t *buf)
305 {
306     scsi_req_build_sense(req, SENSE_CODE(INVALID_FIELD));
307     scsi_req_complete(req, CHECK_CONDITION);
308     return 0;
309 }
310 
311 static const struct SCSIReqOps reqops_invalid_field = {
312     .size         = sizeof(SCSIRequest),
313     .send_command = scsi_invalid_field
314 };
315 
316 /* SCSIReqOps implementation for invalid commands.  */
317 
318 static int32_t scsi_invalid_command(SCSIRequest *req, uint8_t *buf)
319 {
320     scsi_req_build_sense(req, SENSE_CODE(INVALID_OPCODE));
321     scsi_req_complete(req, CHECK_CONDITION);
322     return 0;
323 }
324 
325 static const struct SCSIReqOps reqops_invalid_opcode = {
326     .size         = sizeof(SCSIRequest),
327     .send_command = scsi_invalid_command
328 };
329 
330 /* SCSIReqOps implementation for unit attention conditions.  */
331 
332 static int32_t scsi_unit_attention(SCSIRequest *req, uint8_t *buf)
333 {
334     if (req->dev->unit_attention.key == UNIT_ATTENTION) {
335         scsi_req_build_sense(req, req->dev->unit_attention);
336     } else if (req->bus->unit_attention.key == UNIT_ATTENTION) {
337         scsi_req_build_sense(req, req->bus->unit_attention);
338     }
339     scsi_req_complete(req, CHECK_CONDITION);
340     return 0;
341 }
342 
343 static const struct SCSIReqOps reqops_unit_attention = {
344     .size         = sizeof(SCSIRequest),
345     .send_command = scsi_unit_attention
346 };
347 
348 /* SCSIReqOps implementation for REPORT LUNS and for commands sent to
349    an invalid LUN.  */
350 
351 typedef struct SCSITargetReq SCSITargetReq;
352 
353 struct SCSITargetReq {
354     SCSIRequest req;
355     int len;
356     uint8_t *buf;
357     int buf_len;
358 };
359 
360 static void store_lun(uint8_t *outbuf, int lun)
361 {
362     if (lun < 256) {
363         outbuf[1] = lun;
364         return;
365     }
366     outbuf[1] = (lun & 255);
367     outbuf[0] = (lun >> 8) | 0x40;
368 }
369 
370 static bool scsi_target_emulate_report_luns(SCSITargetReq *r)
371 {
372     BusChild *kid;
373     int i, len, n;
374     int channel, id;
375     bool found_lun0;
376 
377     if (r->req.cmd.xfer < 16) {
378         return false;
379     }
380     if (r->req.cmd.buf[2] > 2) {
381         return false;
382     }
383     channel = r->req.dev->channel;
384     id = r->req.dev->id;
385     found_lun0 = false;
386     n = 0;
387     QTAILQ_FOREACH(kid, &r->req.bus->qbus.children, sibling) {
388         DeviceState *qdev = kid->child;
389         SCSIDevice *dev = SCSI_DEVICE(qdev);
390 
391         if (dev->channel == channel && dev->id == id) {
392             if (dev->lun == 0) {
393                 found_lun0 = true;
394             }
395             n += 8;
396         }
397     }
398     if (!found_lun0) {
399         n += 8;
400     }
401 
402     scsi_target_alloc_buf(&r->req, n + 8);
403 
404     len = MIN(n + 8, r->req.cmd.xfer & ~7);
405     memset(r->buf, 0, len);
406     stl_be_p(&r->buf[0], n);
407     i = found_lun0 ? 8 : 16;
408     QTAILQ_FOREACH(kid, &r->req.bus->qbus.children, sibling) {
409         DeviceState *qdev = kid->child;
410         SCSIDevice *dev = SCSI_DEVICE(qdev);
411 
412         if (dev->channel == channel && dev->id == id) {
413             store_lun(&r->buf[i], dev->lun);
414             i += 8;
415         }
416     }
417     assert(i == n + 8);
418     r->len = len;
419     return true;
420 }
421 
422 static bool scsi_target_emulate_inquiry(SCSITargetReq *r)
423 {
424     assert(r->req.dev->lun != r->req.lun);
425 
426     scsi_target_alloc_buf(&r->req, SCSI_INQUIRY_LEN);
427 
428     if (r->req.cmd.buf[1] & 0x2) {
429         /* Command support data - optional, not implemented */
430         return false;
431     }
432 
433     if (r->req.cmd.buf[1] & 0x1) {
434         /* Vital product data */
435         uint8_t page_code = r->req.cmd.buf[2];
436         r->buf[r->len++] = page_code ; /* this page */
437         r->buf[r->len++] = 0x00;
438 
439         switch (page_code) {
440         case 0x00: /* Supported page codes, mandatory */
441         {
442             int pages;
443             pages = r->len++;
444             r->buf[r->len++] = 0x00; /* list of supported pages (this page) */
445             r->buf[pages] = r->len - pages - 1; /* number of pages */
446             break;
447         }
448         default:
449             return false;
450         }
451         /* done with EVPD */
452         assert(r->len < r->buf_len);
453         r->len = MIN(r->req.cmd.xfer, r->len);
454         return true;
455     }
456 
457     /* Standard INQUIRY data */
458     if (r->req.cmd.buf[2] != 0) {
459         return false;
460     }
461 
462     /* PAGE CODE == 0 */
463     r->len = MIN(r->req.cmd.xfer, SCSI_INQUIRY_LEN);
464     memset(r->buf, 0, r->len);
465     if (r->req.lun != 0) {
466         r->buf[0] = TYPE_NO_LUN;
467     } else {
468         r->buf[0] = TYPE_NOT_PRESENT | TYPE_INACTIVE;
469         r->buf[2] = 5; /* Version */
470         r->buf[3] = 2 | 0x10; /* HiSup, response data format */
471         r->buf[4] = r->len - 5; /* Additional Length = (Len - 1) - 4 */
472         r->buf[7] = 0x10 | (r->req.bus->info->tcq ? 0x02 : 0); /* Sync, TCQ.  */
473         memcpy(&r->buf[8], "QEMU    ", 8);
474         memcpy(&r->buf[16], "QEMU TARGET     ", 16);
475         pstrcpy((char *) &r->buf[32], 4, qemu_hw_version());
476     }
477     return true;
478 }
479 
480 static size_t scsi_sense_len(SCSIRequest *req)
481 {
482     if (req->dev->type == TYPE_SCANNER)
483         return SCSI_SENSE_LEN_SCANNER;
484     else
485         return SCSI_SENSE_LEN;
486 }
487 
488 static int32_t scsi_target_send_command(SCSIRequest *req, uint8_t *buf)
489 {
490     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
491     int fixed_sense = (req->cmd.buf[1] & 1) == 0;
492 
493     if (req->lun != 0 &&
494         buf[0] != INQUIRY && buf[0] != REQUEST_SENSE) {
495         scsi_req_build_sense(req, SENSE_CODE(LUN_NOT_SUPPORTED));
496         scsi_req_complete(req, CHECK_CONDITION);
497         return 0;
498     }
499     switch (buf[0]) {
500     case REPORT_LUNS:
501         if (!scsi_target_emulate_report_luns(r)) {
502             goto illegal_request;
503         }
504         break;
505     case INQUIRY:
506         if (!scsi_target_emulate_inquiry(r)) {
507             goto illegal_request;
508         }
509         break;
510     case REQUEST_SENSE:
511         scsi_target_alloc_buf(&r->req, scsi_sense_len(req));
512         if (req->lun != 0) {
513             const struct SCSISense sense = SENSE_CODE(LUN_NOT_SUPPORTED);
514 
515             r->len = scsi_build_sense_buf(r->buf, req->cmd.xfer,
516                                           sense, fixed_sense);
517         } else {
518             r->len = scsi_device_get_sense(r->req.dev, r->buf,
519                                            MIN(req->cmd.xfer, r->buf_len),
520                                            fixed_sense);
521         }
522         if (r->req.dev->sense_is_ua) {
523             scsi_device_unit_attention_reported(req->dev);
524             r->req.dev->sense_len = 0;
525             r->req.dev->sense_is_ua = false;
526         }
527         break;
528     case TEST_UNIT_READY:
529         break;
530     default:
531         scsi_req_build_sense(req, SENSE_CODE(INVALID_OPCODE));
532         scsi_req_complete(req, CHECK_CONDITION);
533         return 0;
534     illegal_request:
535         scsi_req_build_sense(req, SENSE_CODE(INVALID_FIELD));
536         scsi_req_complete(req, CHECK_CONDITION);
537         return 0;
538     }
539 
540     if (!r->len) {
541         scsi_req_complete(req, GOOD);
542     }
543     return r->len;
544 }
545 
546 static void scsi_target_read_data(SCSIRequest *req)
547 {
548     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
549     uint32_t n;
550 
551     n = r->len;
552     if (n > 0) {
553         r->len = 0;
554         scsi_req_data(&r->req, n);
555     } else {
556         scsi_req_complete(&r->req, GOOD);
557     }
558 }
559 
560 static uint8_t *scsi_target_get_buf(SCSIRequest *req)
561 {
562     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
563 
564     return r->buf;
565 }
566 
567 static uint8_t *scsi_target_alloc_buf(SCSIRequest *req, size_t len)
568 {
569     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
570 
571     r->buf = g_malloc(len);
572     r->buf_len = len;
573 
574     return r->buf;
575 }
576 
577 static void scsi_target_free_buf(SCSIRequest *req)
578 {
579     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
580 
581     g_free(r->buf);
582 }
583 
584 static const struct SCSIReqOps reqops_target_command = {
585     .size         = sizeof(SCSITargetReq),
586     .send_command = scsi_target_send_command,
587     .read_data    = scsi_target_read_data,
588     .get_buf      = scsi_target_get_buf,
589     .free_req     = scsi_target_free_buf,
590 };
591 
592 
593 SCSIRequest *scsi_req_alloc(const SCSIReqOps *reqops, SCSIDevice *d,
594                             uint32_t tag, uint32_t lun, void *hba_private)
595 {
596     SCSIRequest *req;
597     SCSIBus *bus = scsi_bus_from_device(d);
598     BusState *qbus = BUS(bus);
599     const int memset_off = offsetof(SCSIRequest, sense)
600                            + sizeof(req->sense);
601 
602     req = g_malloc(reqops->size);
603     memset((uint8_t *)req + memset_off, 0, reqops->size - memset_off);
604     req->refcount = 1;
605     req->bus = bus;
606     req->dev = d;
607     req->tag = tag;
608     req->lun = lun;
609     req->hba_private = hba_private;
610     req->status = -1;
611     req->ops = reqops;
612     object_ref(OBJECT(d));
613     object_ref(OBJECT(qbus->parent));
614     notifier_list_init(&req->cancel_notifiers);
615     trace_scsi_req_alloc(req->dev->id, req->lun, req->tag);
616     return req;
617 }
618 
619 SCSIRequest *scsi_req_new(SCSIDevice *d, uint32_t tag, uint32_t lun,
620                           uint8_t *buf, void *hba_private)
621 {
622     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, d->qdev.parent_bus);
623     const SCSIReqOps *ops;
624     SCSIDeviceClass *sc = SCSI_DEVICE_GET_CLASS(d);
625     SCSIRequest *req;
626     SCSICommand cmd = { .len = 0 };
627     int ret;
628 
629     if ((d->unit_attention.key == UNIT_ATTENTION ||
630          bus->unit_attention.key == UNIT_ATTENTION) &&
631         (buf[0] != INQUIRY &&
632          buf[0] != REPORT_LUNS &&
633          buf[0] != GET_CONFIGURATION &&
634          buf[0] != GET_EVENT_STATUS_NOTIFICATION &&
635 
636          /*
637           * If we already have a pending unit attention condition,
638           * report this one before triggering another one.
639           */
640          !(buf[0] == REQUEST_SENSE && d->sense_is_ua))) {
641         ops = &reqops_unit_attention;
642     } else if (lun != d->lun ||
643                buf[0] == REPORT_LUNS ||
644                (buf[0] == REQUEST_SENSE && d->sense_len)) {
645         ops = &reqops_target_command;
646     } else {
647         ops = NULL;
648     }
649 
650     if (ops != NULL || !sc->parse_cdb) {
651         ret = scsi_req_parse_cdb(d, &cmd, buf);
652     } else {
653         ret = sc->parse_cdb(d, &cmd, buf, hba_private);
654     }
655 
656     if (ret != 0) {
657         trace_scsi_req_parse_bad(d->id, lun, tag, buf[0]);
658         req = scsi_req_alloc(&reqops_invalid_opcode, d, tag, lun, hba_private);
659     } else {
660         assert(cmd.len != 0);
661         trace_scsi_req_parsed(d->id, lun, tag, buf[0],
662                               cmd.mode, cmd.xfer);
663         if (cmd.lba != -1) {
664             trace_scsi_req_parsed_lba(d->id, lun, tag, buf[0],
665                                       cmd.lba);
666         }
667 
668         if (cmd.xfer > INT32_MAX) {
669             req = scsi_req_alloc(&reqops_invalid_field, d, tag, lun, hba_private);
670         } else if (ops) {
671             req = scsi_req_alloc(ops, d, tag, lun, hba_private);
672         } else {
673             req = scsi_device_alloc_req(d, tag, lun, buf, hba_private);
674         }
675     }
676 
677     req->cmd = cmd;
678     req->resid = req->cmd.xfer;
679 
680     switch (buf[0]) {
681     case INQUIRY:
682         trace_scsi_inquiry(d->id, lun, tag, cmd.buf[1], cmd.buf[2]);
683         break;
684     case TEST_UNIT_READY:
685         trace_scsi_test_unit_ready(d->id, lun, tag);
686         break;
687     case REPORT_LUNS:
688         trace_scsi_report_luns(d->id, lun, tag);
689         break;
690     case REQUEST_SENSE:
691         trace_scsi_request_sense(d->id, lun, tag);
692         break;
693     default:
694         break;
695     }
696 
697     return req;
698 }
699 
700 uint8_t *scsi_req_get_buf(SCSIRequest *req)
701 {
702     return req->ops->get_buf(req);
703 }
704 
705 static void scsi_clear_unit_attention(SCSIRequest *req)
706 {
707     SCSISense *ua;
708     if (req->dev->unit_attention.key != UNIT_ATTENTION &&
709         req->bus->unit_attention.key != UNIT_ATTENTION) {
710         return;
711     }
712 
713     /*
714      * If an INQUIRY command enters the enabled command state,
715      * the device server shall [not] clear any unit attention condition;
716      * See also MMC-6, paragraphs 6.5 and 6.6.2.
717      */
718     if (req->cmd.buf[0] == INQUIRY ||
719         req->cmd.buf[0] == GET_CONFIGURATION ||
720         req->cmd.buf[0] == GET_EVENT_STATUS_NOTIFICATION) {
721         return;
722     }
723 
724     if (req->dev->unit_attention.key == UNIT_ATTENTION) {
725         ua = &req->dev->unit_attention;
726     } else {
727         ua = &req->bus->unit_attention;
728     }
729 
730     /*
731      * If a REPORT LUNS command enters the enabled command state, [...]
732      * the device server shall clear any pending unit attention condition
733      * with an additional sense code of REPORTED LUNS DATA HAS CHANGED.
734      */
735     if (req->cmd.buf[0] == REPORT_LUNS &&
736         !(ua->asc == SENSE_CODE(REPORTED_LUNS_CHANGED).asc &&
737           ua->ascq == SENSE_CODE(REPORTED_LUNS_CHANGED).ascq)) {
738         return;
739     }
740 
741     *ua = SENSE_CODE(NO_SENSE);
742 }
743 
744 int scsi_req_get_sense(SCSIRequest *req, uint8_t *buf, int len)
745 {
746     int ret;
747 
748     assert(len >= 14);
749     if (!req->sense_len) {
750         return 0;
751     }
752 
753     ret = scsi_convert_sense(req->sense, req->sense_len, buf, len, true);
754 
755     /*
756      * FIXME: clearing unit attention conditions upon autosense should be done
757      * only if the UA_INTLCK_CTRL field in the Control mode page is set to 00b
758      * (SAM-5, 5.14).
759      *
760      * We assume UA_INTLCK_CTRL to be 00b for HBAs that support autosense, and
761      * 10b for HBAs that do not support it (do not call scsi_req_get_sense).
762      * Here we handle unit attention clearing for UA_INTLCK_CTRL == 00b.
763      */
764     if (req->dev->sense_is_ua) {
765         scsi_device_unit_attention_reported(req->dev);
766         req->dev->sense_len = 0;
767         req->dev->sense_is_ua = false;
768     }
769     return ret;
770 }
771 
772 int scsi_device_get_sense(SCSIDevice *dev, uint8_t *buf, int len, bool fixed)
773 {
774     return scsi_convert_sense(dev->sense, dev->sense_len, buf, len, fixed);
775 }
776 
777 void scsi_req_build_sense(SCSIRequest *req, SCSISense sense)
778 {
779     trace_scsi_req_build_sense(req->dev->id, req->lun, req->tag,
780                                sense.key, sense.asc, sense.ascq);
781     req->sense_len = scsi_build_sense(req->sense, sense);
782 }
783 
784 static void scsi_req_enqueue_internal(SCSIRequest *req)
785 {
786     assert(!req->enqueued);
787     scsi_req_ref(req);
788     if (req->bus->info->get_sg_list) {
789         req->sg = req->bus->info->get_sg_list(req);
790     } else {
791         req->sg = NULL;
792     }
793     req->enqueued = true;
794     QTAILQ_INSERT_TAIL(&req->dev->requests, req, next);
795 }
796 
797 int32_t scsi_req_enqueue(SCSIRequest *req)
798 {
799     int32_t rc;
800 
801     assert(!req->retry);
802     scsi_req_enqueue_internal(req);
803     scsi_req_ref(req);
804     rc = req->ops->send_command(req, req->cmd.buf);
805     scsi_req_unref(req);
806     return rc;
807 }
808 
809 static void scsi_req_dequeue(SCSIRequest *req)
810 {
811     trace_scsi_req_dequeue(req->dev->id, req->lun, req->tag);
812     req->retry = false;
813     if (req->enqueued) {
814         QTAILQ_REMOVE(&req->dev->requests, req, next);
815         req->enqueued = false;
816         scsi_req_unref(req);
817     }
818 }
819 
820 static int scsi_get_performance_length(int num_desc, int type, int data_type)
821 {
822     /* MMC-6, paragraph 6.7.  */
823     switch (type) {
824     case 0:
825         if ((data_type & 3) == 0) {
826             /* Each descriptor is as in Table 295 - Nominal performance.  */
827             return 16 * num_desc + 8;
828         } else {
829             /* Each descriptor is as in Table 296 - Exceptions.  */
830             return 6 * num_desc + 8;
831         }
832     case 1:
833     case 4:
834     case 5:
835         return 8 * num_desc + 8;
836     case 2:
837         return 2048 * num_desc + 8;
838     case 3:
839         return 16 * num_desc + 8;
840     default:
841         return 8;
842     }
843 }
844 
845 static int ata_passthrough_xfer_unit(SCSIDevice *dev, uint8_t *buf)
846 {
847     int byte_block = (buf[2] >> 2) & 0x1;
848     int type = (buf[2] >> 4) & 0x1;
849     int xfer_unit;
850 
851     if (byte_block) {
852         if (type) {
853             xfer_unit = dev->blocksize;
854         } else {
855             xfer_unit = 512;
856         }
857     } else {
858         xfer_unit = 1;
859     }
860 
861     return xfer_unit;
862 }
863 
864 static int ata_passthrough_12_xfer(SCSIDevice *dev, uint8_t *buf)
865 {
866     int length = buf[2] & 0x3;
867     int xfer;
868     int unit = ata_passthrough_xfer_unit(dev, buf);
869 
870     switch (length) {
871     case 0:
872     case 3: /* USB-specific.  */
873     default:
874         xfer = 0;
875         break;
876     case 1:
877         xfer = buf[3];
878         break;
879     case 2:
880         xfer = buf[4];
881         break;
882     }
883 
884     return xfer * unit;
885 }
886 
887 static int ata_passthrough_16_xfer(SCSIDevice *dev, uint8_t *buf)
888 {
889     int extend = buf[1] & 0x1;
890     int length = buf[2] & 0x3;
891     int xfer;
892     int unit = ata_passthrough_xfer_unit(dev, buf);
893 
894     switch (length) {
895     case 0:
896     case 3: /* USB-specific.  */
897     default:
898         xfer = 0;
899         break;
900     case 1:
901         xfer = buf[4];
902         xfer |= (extend ? buf[3] << 8 : 0);
903         break;
904     case 2:
905         xfer = buf[6];
906         xfer |= (extend ? buf[5] << 8 : 0);
907         break;
908     }
909 
910     return xfer * unit;
911 }
912 
913 static int scsi_req_xfer(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
914 {
915     cmd->xfer = scsi_cdb_xfer(buf);
916     switch (buf[0]) {
917     case TEST_UNIT_READY:
918     case REWIND:
919     case START_STOP:
920     case SET_CAPACITY:
921     case WRITE_FILEMARKS:
922     case WRITE_FILEMARKS_16:
923     case SPACE:
924     case RESERVE:
925     case RELEASE:
926     case ERASE:
927     case ALLOW_MEDIUM_REMOVAL:
928     case SEEK_10:
929     case SYNCHRONIZE_CACHE:
930     case SYNCHRONIZE_CACHE_16:
931     case LOCATE_16:
932     case LOCK_UNLOCK_CACHE:
933     case SET_CD_SPEED:
934     case SET_LIMITS:
935     case WRITE_LONG_10:
936     case UPDATE_BLOCK:
937     case RESERVE_TRACK:
938     case SET_READ_AHEAD:
939     case PRE_FETCH:
940     case PRE_FETCH_16:
941     case ALLOW_OVERWRITE:
942         cmd->xfer = 0;
943         break;
944     case VERIFY_10:
945     case VERIFY_12:
946     case VERIFY_16:
947         if ((buf[1] & 2) == 0) {
948             cmd->xfer = 0;
949         } else if ((buf[1] & 4) != 0) {
950             cmd->xfer = 1;
951         }
952         cmd->xfer *= dev->blocksize;
953         break;
954     case MODE_SENSE:
955         break;
956     case WRITE_SAME_10:
957     case WRITE_SAME_16:
958         cmd->xfer = buf[1] & 1 ? 0 : dev->blocksize;
959         break;
960     case READ_CAPACITY_10:
961         cmd->xfer = 8;
962         break;
963     case READ_BLOCK_LIMITS:
964         cmd->xfer = 6;
965         break;
966     case SEND_VOLUME_TAG:
967         /* GPCMD_SET_STREAMING from multimedia commands.  */
968         if (dev->type == TYPE_ROM) {
969             cmd->xfer = buf[10] | (buf[9] << 8);
970         } else {
971             cmd->xfer = buf[9] | (buf[8] << 8);
972         }
973         break;
974     case WRITE_6:
975         /* length 0 means 256 blocks */
976         if (cmd->xfer == 0) {
977             cmd->xfer = 256;
978         }
979         /* fall through */
980     case WRITE_10:
981     case WRITE_VERIFY_10:
982     case WRITE_12:
983     case WRITE_VERIFY_12:
984     case WRITE_16:
985     case WRITE_VERIFY_16:
986         cmd->xfer *= dev->blocksize;
987         break;
988     case READ_6:
989     case READ_REVERSE:
990         /* length 0 means 256 blocks */
991         if (cmd->xfer == 0) {
992             cmd->xfer = 256;
993         }
994         /* fall through */
995     case READ_10:
996     case READ_12:
997     case READ_16:
998         cmd->xfer *= dev->blocksize;
999         break;
1000     case FORMAT_UNIT:
1001         /* MMC mandates the parameter list to be 12-bytes long.  Parameters
1002          * for block devices are restricted to the header right now.  */
1003         if (dev->type == TYPE_ROM && (buf[1] & 16)) {
1004             cmd->xfer = 12;
1005         } else {
1006             cmd->xfer = (buf[1] & 16) == 0 ? 0 : (buf[1] & 32 ? 8 : 4);
1007         }
1008         break;
1009     case INQUIRY:
1010     case RECEIVE_DIAGNOSTIC:
1011     case SEND_DIAGNOSTIC:
1012         cmd->xfer = buf[4] | (buf[3] << 8);
1013         break;
1014     case READ_CD:
1015     case READ_BUFFER:
1016     case WRITE_BUFFER:
1017     case SEND_CUE_SHEET:
1018         cmd->xfer = buf[8] | (buf[7] << 8) | (buf[6] << 16);
1019         break;
1020     case PERSISTENT_RESERVE_OUT:
1021         cmd->xfer = ldl_be_p(&buf[5]) & 0xffffffffULL;
1022         break;
1023     case ERASE_12:
1024         if (dev->type == TYPE_ROM) {
1025             /* MMC command GET PERFORMANCE.  */
1026             cmd->xfer = scsi_get_performance_length(buf[9] | (buf[8] << 8),
1027                                                     buf[10], buf[1] & 0x1f);
1028         }
1029         break;
1030     case MECHANISM_STATUS:
1031     case READ_DVD_STRUCTURE:
1032     case SEND_DVD_STRUCTURE:
1033     case MAINTENANCE_OUT:
1034     case MAINTENANCE_IN:
1035         if (dev->type == TYPE_ROM) {
1036             /* GPCMD_REPORT_KEY and GPCMD_SEND_KEY from multi media commands */
1037             cmd->xfer = buf[9] | (buf[8] << 8);
1038         }
1039         break;
1040     case ATA_PASSTHROUGH_12:
1041         if (dev->type == TYPE_ROM) {
1042             /* BLANK command of MMC */
1043             cmd->xfer = 0;
1044         } else {
1045             cmd->xfer = ata_passthrough_12_xfer(dev, buf);
1046         }
1047         break;
1048     case ATA_PASSTHROUGH_16:
1049         cmd->xfer = ata_passthrough_16_xfer(dev, buf);
1050         break;
1051     }
1052     return 0;
1053 }
1054 
1055 static int scsi_req_stream_xfer(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
1056 {
1057     switch (buf[0]) {
1058     /* stream commands */
1059     case ERASE_12:
1060     case ERASE_16:
1061         cmd->xfer = 0;
1062         break;
1063     case READ_6:
1064     case READ_REVERSE:
1065     case RECOVER_BUFFERED_DATA:
1066     case WRITE_6:
1067         cmd->xfer = buf[4] | (buf[3] << 8) | (buf[2] << 16);
1068         if (buf[1] & 0x01) { /* fixed */
1069             cmd->xfer *= dev->blocksize;
1070         }
1071         break;
1072     case READ_16:
1073     case READ_REVERSE_16:
1074     case VERIFY_16:
1075     case WRITE_16:
1076         cmd->xfer = buf[14] | (buf[13] << 8) | (buf[12] << 16);
1077         if (buf[1] & 0x01) { /* fixed */
1078             cmd->xfer *= dev->blocksize;
1079         }
1080         break;
1081     case REWIND:
1082     case LOAD_UNLOAD:
1083         cmd->xfer = 0;
1084         break;
1085     case SPACE_16:
1086         cmd->xfer = buf[13] | (buf[12] << 8);
1087         break;
1088     case READ_POSITION:
1089         switch (buf[1] & 0x1f) /* operation code */ {
1090         case SHORT_FORM_BLOCK_ID:
1091         case SHORT_FORM_VENDOR_SPECIFIC:
1092             cmd->xfer = 20;
1093             break;
1094         case LONG_FORM:
1095             cmd->xfer = 32;
1096             break;
1097         case EXTENDED_FORM:
1098             cmd->xfer = buf[8] | (buf[7] << 8);
1099             break;
1100         default:
1101             return -1;
1102         }
1103 
1104         break;
1105     case FORMAT_UNIT:
1106         cmd->xfer = buf[4] | (buf[3] << 8);
1107         break;
1108     /* generic commands */
1109     default:
1110         return scsi_req_xfer(cmd, dev, buf);
1111     }
1112     return 0;
1113 }
1114 
1115 static int scsi_req_medium_changer_xfer(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
1116 {
1117     switch (buf[0]) {
1118     /* medium changer commands */
1119     case EXCHANGE_MEDIUM:
1120     case INITIALIZE_ELEMENT_STATUS:
1121     case INITIALIZE_ELEMENT_STATUS_WITH_RANGE:
1122     case MOVE_MEDIUM:
1123     case POSITION_TO_ELEMENT:
1124         cmd->xfer = 0;
1125         break;
1126     case READ_ELEMENT_STATUS:
1127         cmd->xfer = buf[9] | (buf[8] << 8) | (buf[7] << 16);
1128         break;
1129 
1130     /* generic commands */
1131     default:
1132         return scsi_req_xfer(cmd, dev, buf);
1133     }
1134     return 0;
1135 }
1136 
1137 static int scsi_req_scanner_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
1138 {
1139     switch (buf[0]) {
1140     /* Scanner commands */
1141     case OBJECT_POSITION:
1142         cmd->xfer = 0;
1143         break;
1144     case SCAN:
1145         cmd->xfer = buf[4];
1146         break;
1147     case READ_10:
1148     case SEND:
1149     case GET_WINDOW:
1150     case SET_WINDOW:
1151         cmd->xfer = buf[8] | (buf[7] << 8) | (buf[6] << 16);
1152         break;
1153     default:
1154         /* GET_DATA_BUFFER_STATUS xfer handled by scsi_req_xfer */
1155         return scsi_req_xfer(cmd, dev, buf);
1156     }
1157 
1158     return 0;
1159 }
1160 
1161 static void scsi_cmd_xfer_mode(SCSICommand *cmd)
1162 {
1163     if (!cmd->xfer) {
1164         cmd->mode = SCSI_XFER_NONE;
1165         return;
1166     }
1167     switch (cmd->buf[0]) {
1168     case WRITE_6:
1169     case WRITE_10:
1170     case WRITE_VERIFY_10:
1171     case WRITE_12:
1172     case WRITE_VERIFY_12:
1173     case WRITE_16:
1174     case WRITE_VERIFY_16:
1175     case VERIFY_10:
1176     case VERIFY_12:
1177     case VERIFY_16:
1178     case COPY:
1179     case COPY_VERIFY:
1180     case COMPARE:
1181     case CHANGE_DEFINITION:
1182     case LOG_SELECT:
1183     case MODE_SELECT:
1184     case MODE_SELECT_10:
1185     case SEND_DIAGNOSTIC:
1186     case WRITE_BUFFER:
1187     case FORMAT_UNIT:
1188     case REASSIGN_BLOCKS:
1189     case SEARCH_EQUAL:
1190     case SEARCH_HIGH:
1191     case SEARCH_LOW:
1192     case UPDATE_BLOCK:
1193     case WRITE_LONG_10:
1194     case WRITE_SAME_10:
1195     case WRITE_SAME_16:
1196     case UNMAP:
1197     case SEARCH_HIGH_12:
1198     case SEARCH_EQUAL_12:
1199     case SEARCH_LOW_12:
1200     case MEDIUM_SCAN:
1201     case SEND_VOLUME_TAG:
1202     case SEND_CUE_SHEET:
1203     case SEND_DVD_STRUCTURE:
1204     case PERSISTENT_RESERVE_OUT:
1205     case MAINTENANCE_OUT:
1206     case SET_WINDOW:
1207     case SCAN:
1208         /* SCAN conflicts with START_STOP.  START_STOP has cmd->xfer set to 0 for
1209          * non-scanner devices, so we only get here for SCAN and not for START_STOP.
1210          */
1211         cmd->mode = SCSI_XFER_TO_DEV;
1212         break;
1213     case ATA_PASSTHROUGH_12:
1214     case ATA_PASSTHROUGH_16:
1215         /* T_DIR */
1216         cmd->mode = (cmd->buf[2] & 0x8) ?
1217                    SCSI_XFER_FROM_DEV : SCSI_XFER_TO_DEV;
1218         break;
1219     default:
1220         cmd->mode = SCSI_XFER_FROM_DEV;
1221         break;
1222     }
1223 }
1224 
1225 int scsi_req_parse_cdb(SCSIDevice *dev, SCSICommand *cmd, uint8_t *buf)
1226 {
1227     int rc;
1228     int len;
1229 
1230     cmd->lba = -1;
1231     len = scsi_cdb_length(buf);
1232     if (len < 0) {
1233         return -1;
1234     }
1235 
1236     cmd->len = len;
1237     switch (dev->type) {
1238     case TYPE_TAPE:
1239         rc = scsi_req_stream_xfer(cmd, dev, buf);
1240         break;
1241     case TYPE_MEDIUM_CHANGER:
1242         rc = scsi_req_medium_changer_xfer(cmd, dev, buf);
1243         break;
1244     case TYPE_SCANNER:
1245         rc = scsi_req_scanner_length(cmd, dev, buf);
1246         break;
1247     default:
1248         rc = scsi_req_xfer(cmd, dev, buf);
1249         break;
1250     }
1251 
1252     if (rc != 0)
1253         return rc;
1254 
1255     memcpy(cmd->buf, buf, cmd->len);
1256     scsi_cmd_xfer_mode(cmd);
1257     cmd->lba = scsi_cmd_lba(cmd);
1258     return 0;
1259 }
1260 
1261 void scsi_device_report_change(SCSIDevice *dev, SCSISense sense)
1262 {
1263     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, dev->qdev.parent_bus);
1264 
1265     scsi_device_set_ua(dev, sense);
1266     if (bus->info->change) {
1267         bus->info->change(bus, dev, sense);
1268     }
1269 }
1270 
1271 SCSIRequest *scsi_req_ref(SCSIRequest *req)
1272 {
1273     assert(req->refcount > 0);
1274     req->refcount++;
1275     return req;
1276 }
1277 
1278 void scsi_req_unref(SCSIRequest *req)
1279 {
1280     assert(req->refcount > 0);
1281     if (--req->refcount == 0) {
1282         BusState *qbus = req->dev->qdev.parent_bus;
1283         SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, qbus);
1284 
1285         if (bus->info->free_request && req->hba_private) {
1286             bus->info->free_request(bus, req->hba_private);
1287         }
1288         if (req->ops->free_req) {
1289             req->ops->free_req(req);
1290         }
1291         object_unref(OBJECT(req->dev));
1292         object_unref(OBJECT(qbus->parent));
1293         g_free(req);
1294     }
1295 }
1296 
1297 /* Tell the device that we finished processing this chunk of I/O.  It
1298    will start the next chunk or complete the command.  */
1299 void scsi_req_continue(SCSIRequest *req)
1300 {
1301     if (req->io_canceled) {
1302         trace_scsi_req_continue_canceled(req->dev->id, req->lun, req->tag);
1303         return;
1304     }
1305     trace_scsi_req_continue(req->dev->id, req->lun, req->tag);
1306     if (req->cmd.mode == SCSI_XFER_TO_DEV) {
1307         req->ops->write_data(req);
1308     } else {
1309         req->ops->read_data(req);
1310     }
1311 }
1312 
1313 /* Called by the devices when data is ready for the HBA.  The HBA should
1314    start a DMA operation to read or fill the device's data buffer.
1315    Once it completes, calling scsi_req_continue will restart I/O.  */
1316 void scsi_req_data(SCSIRequest *req, int len)
1317 {
1318     uint8_t *buf;
1319     if (req->io_canceled) {
1320         trace_scsi_req_data_canceled(req->dev->id, req->lun, req->tag, len);
1321         return;
1322     }
1323     trace_scsi_req_data(req->dev->id, req->lun, req->tag, len);
1324     assert(req->cmd.mode != SCSI_XFER_NONE);
1325     if (!req->sg) {
1326         req->resid -= len;
1327         req->bus->info->transfer_data(req, len);
1328         return;
1329     }
1330 
1331     /* If the device calls scsi_req_data and the HBA specified a
1332      * scatter/gather list, the transfer has to happen in a single
1333      * step.  */
1334     assert(!req->dma_started);
1335     req->dma_started = true;
1336 
1337     buf = scsi_req_get_buf(req);
1338     if (req->cmd.mode == SCSI_XFER_FROM_DEV) {
1339         req->resid = dma_buf_read(buf, len, req->sg);
1340     } else {
1341         req->resid = dma_buf_write(buf, len, req->sg);
1342     }
1343     scsi_req_continue(req);
1344 }
1345 
1346 void scsi_req_print(SCSIRequest *req)
1347 {
1348     FILE *fp = stderr;
1349     int i;
1350 
1351     fprintf(fp, "[%s id=%d] %s",
1352             req->dev->qdev.parent_bus->name,
1353             req->dev->id,
1354             scsi_command_name(req->cmd.buf[0]));
1355     for (i = 1; i < req->cmd.len; i++) {
1356         fprintf(fp, " 0x%02x", req->cmd.buf[i]);
1357     }
1358     switch (req->cmd.mode) {
1359     case SCSI_XFER_NONE:
1360         fprintf(fp, " - none\n");
1361         break;
1362     case SCSI_XFER_FROM_DEV:
1363         fprintf(fp, " - from-dev len=%zd\n", req->cmd.xfer);
1364         break;
1365     case SCSI_XFER_TO_DEV:
1366         fprintf(fp, " - to-dev len=%zd\n", req->cmd.xfer);
1367         break;
1368     default:
1369         fprintf(fp, " - Oops\n");
1370         break;
1371     }
1372 }
1373 
1374 void scsi_req_complete(SCSIRequest *req, int status)
1375 {
1376     assert(req->status == -1);
1377     req->status = status;
1378 
1379     assert(req->sense_len <= sizeof(req->sense));
1380     if (status == GOOD) {
1381         req->sense_len = 0;
1382     }
1383 
1384     if (req->sense_len) {
1385         memcpy(req->dev->sense, req->sense, req->sense_len);
1386         req->dev->sense_len = req->sense_len;
1387         req->dev->sense_is_ua = (req->ops == &reqops_unit_attention);
1388     } else {
1389         req->dev->sense_len = 0;
1390         req->dev->sense_is_ua = false;
1391     }
1392 
1393     /*
1394      * Unit attention state is now stored in the device's sense buffer
1395      * if the HBA didn't do autosense.  Clear the pending unit attention
1396      * flags.
1397      */
1398     scsi_clear_unit_attention(req);
1399 
1400     scsi_req_ref(req);
1401     scsi_req_dequeue(req);
1402     req->bus->info->complete(req, req->status, req->resid);
1403 
1404     /* Cancelled requests might end up being completed instead of cancelled */
1405     notifier_list_notify(&req->cancel_notifiers, req);
1406     scsi_req_unref(req);
1407 }
1408 
1409 /* Called by the devices when the request is canceled. */
1410 void scsi_req_cancel_complete(SCSIRequest *req)
1411 {
1412     assert(req->io_canceled);
1413     if (req->bus->info->cancel) {
1414         req->bus->info->cancel(req);
1415     }
1416     notifier_list_notify(&req->cancel_notifiers, req);
1417     scsi_req_unref(req);
1418 }
1419 
1420 /* Cancel @req asynchronously. @notifier is added to @req's cancellation
1421  * notifier list, the bus will be notified the requests cancellation is
1422  * completed.
1423  * */
1424 void scsi_req_cancel_async(SCSIRequest *req, Notifier *notifier)
1425 {
1426     trace_scsi_req_cancel(req->dev->id, req->lun, req->tag);
1427     if (notifier) {
1428         notifier_list_add(&req->cancel_notifiers, notifier);
1429     }
1430     if (req->io_canceled) {
1431         /* A blk_aio_cancel_async is pending; when it finishes,
1432          * scsi_req_cancel_complete will be called and will
1433          * call the notifier we just added.  Just wait for that.
1434          */
1435         assert(req->aiocb);
1436         return;
1437     }
1438     /* Dropped in scsi_req_cancel_complete.  */
1439     scsi_req_ref(req);
1440     scsi_req_dequeue(req);
1441     req->io_canceled = true;
1442     if (req->aiocb) {
1443         blk_aio_cancel_async(req->aiocb);
1444     } else {
1445         scsi_req_cancel_complete(req);
1446     }
1447 }
1448 
1449 void scsi_req_cancel(SCSIRequest *req)
1450 {
1451     trace_scsi_req_cancel(req->dev->id, req->lun, req->tag);
1452     if (!req->enqueued) {
1453         return;
1454     }
1455     assert(!req->io_canceled);
1456     /* Dropped in scsi_req_cancel_complete.  */
1457     scsi_req_ref(req);
1458     scsi_req_dequeue(req);
1459     req->io_canceled = true;
1460     if (req->aiocb) {
1461         blk_aio_cancel(req->aiocb);
1462     } else {
1463         scsi_req_cancel_complete(req);
1464     }
1465 }
1466 
1467 static int scsi_ua_precedence(SCSISense sense)
1468 {
1469     if (sense.key != UNIT_ATTENTION) {
1470         return INT_MAX;
1471     }
1472     if (sense.asc == 0x29 && sense.ascq == 0x04) {
1473         /* DEVICE INTERNAL RESET goes with POWER ON OCCURRED */
1474         return 1;
1475     } else if (sense.asc == 0x3F && sense.ascq == 0x01) {
1476         /* MICROCODE HAS BEEN CHANGED goes with SCSI BUS RESET OCCURRED */
1477         return 2;
1478     } else if (sense.asc == 0x29 && (sense.ascq == 0x05 || sense.ascq == 0x06)) {
1479         /* These two go with "all others". */
1480         ;
1481     } else if (sense.asc == 0x29 && sense.ascq <= 0x07) {
1482         /* POWER ON, RESET OR BUS DEVICE RESET OCCURRED = 0
1483          * POWER ON OCCURRED = 1
1484          * SCSI BUS RESET OCCURRED = 2
1485          * BUS DEVICE RESET FUNCTION OCCURRED = 3
1486          * I_T NEXUS LOSS OCCURRED = 7
1487          */
1488         return sense.ascq;
1489     } else if (sense.asc == 0x2F && sense.ascq == 0x01) {
1490         /* COMMANDS CLEARED BY POWER LOSS NOTIFICATION  */
1491         return 8;
1492     }
1493     return (sense.asc << 8) | sense.ascq;
1494 }
1495 
1496 void scsi_device_set_ua(SCSIDevice *sdev, SCSISense sense)
1497 {
1498     int prec1, prec2;
1499     if (sense.key != UNIT_ATTENTION) {
1500         return;
1501     }
1502     trace_scsi_device_set_ua(sdev->id, sdev->lun, sense.key,
1503                              sense.asc, sense.ascq);
1504 
1505     /*
1506      * Override a pre-existing unit attention condition, except for a more
1507      * important reset condition.
1508     */
1509     prec1 = scsi_ua_precedence(sdev->unit_attention);
1510     prec2 = scsi_ua_precedence(sense);
1511     if (prec2 < prec1) {
1512         sdev->unit_attention = sense;
1513     }
1514 }
1515 
1516 void scsi_device_purge_requests(SCSIDevice *sdev, SCSISense sense)
1517 {
1518     SCSIRequest *req;
1519 
1520     aio_context_acquire(blk_get_aio_context(sdev->conf.blk));
1521     while (!QTAILQ_EMPTY(&sdev->requests)) {
1522         req = QTAILQ_FIRST(&sdev->requests);
1523         scsi_req_cancel_async(req, NULL);
1524     }
1525     blk_drain(sdev->conf.blk);
1526     aio_context_release(blk_get_aio_context(sdev->conf.blk));
1527     scsi_device_set_ua(sdev, sense);
1528 }
1529 
1530 static char *scsibus_get_dev_path(DeviceState *dev)
1531 {
1532     SCSIDevice *d = SCSI_DEVICE(dev);
1533     DeviceState *hba = dev->parent_bus->parent;
1534     char *id;
1535     char *path;
1536 
1537     id = qdev_get_dev_path(hba);
1538     if (id) {
1539         path = g_strdup_printf("%s/%d:%d:%d", id, d->channel, d->id, d->lun);
1540     } else {
1541         path = g_strdup_printf("%d:%d:%d", d->channel, d->id, d->lun);
1542     }
1543     g_free(id);
1544     return path;
1545 }
1546 
1547 static char *scsibus_get_fw_dev_path(DeviceState *dev)
1548 {
1549     SCSIDevice *d = SCSI_DEVICE(dev);
1550     return g_strdup_printf("channel@%x/%s@%x,%x", d->channel,
1551                            qdev_fw_name(dev), d->id, d->lun);
1552 }
1553 
1554 SCSIDevice *scsi_device_find(SCSIBus *bus, int channel, int id, int lun)
1555 {
1556     BusChild *kid;
1557     SCSIDevice *target_dev = NULL;
1558 
1559     QTAILQ_FOREACH_REVERSE(kid, &bus->qbus.children, sibling) {
1560         DeviceState *qdev = kid->child;
1561         SCSIDevice *dev = SCSI_DEVICE(qdev);
1562 
1563         if (dev->channel == channel && dev->id == id) {
1564             if (dev->lun == lun) {
1565                 return dev;
1566             }
1567             target_dev = dev;
1568         }
1569     }
1570     return target_dev;
1571 }
1572 
1573 /* SCSI request list.  For simplicity, pv points to the whole device */
1574 
1575 static int put_scsi_requests(QEMUFile *f, void *pv, size_t size,
1576                              const VMStateField *field, QJSON *vmdesc)
1577 {
1578     SCSIDevice *s = pv;
1579     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, s->qdev.parent_bus);
1580     SCSIRequest *req;
1581 
1582     QTAILQ_FOREACH(req, &s->requests, next) {
1583         assert(!req->io_canceled);
1584         assert(req->status == -1);
1585         assert(req->enqueued);
1586 
1587         qemu_put_sbyte(f, req->retry ? 1 : 2);
1588         qemu_put_buffer(f, req->cmd.buf, sizeof(req->cmd.buf));
1589         qemu_put_be32s(f, &req->tag);
1590         qemu_put_be32s(f, &req->lun);
1591         if (bus->info->save_request) {
1592             bus->info->save_request(f, req);
1593         }
1594         if (req->ops->save_request) {
1595             req->ops->save_request(f, req);
1596         }
1597     }
1598     qemu_put_sbyte(f, 0);
1599 
1600     return 0;
1601 }
1602 
1603 static int get_scsi_requests(QEMUFile *f, void *pv, size_t size,
1604                              const VMStateField *field)
1605 {
1606     SCSIDevice *s = pv;
1607     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, s->qdev.parent_bus);
1608     int8_t sbyte;
1609 
1610     while ((sbyte = qemu_get_sbyte(f)) > 0) {
1611         uint8_t buf[SCSI_CMD_BUF_SIZE];
1612         uint32_t tag;
1613         uint32_t lun;
1614         SCSIRequest *req;
1615 
1616         qemu_get_buffer(f, buf, sizeof(buf));
1617         qemu_get_be32s(f, &tag);
1618         qemu_get_be32s(f, &lun);
1619         req = scsi_req_new(s, tag, lun, buf, NULL);
1620         req->retry = (sbyte == 1);
1621         if (bus->info->load_request) {
1622             req->hba_private = bus->info->load_request(f, req);
1623         }
1624         if (req->ops->load_request) {
1625             req->ops->load_request(f, req);
1626         }
1627 
1628         /* Just restart it later.  */
1629         scsi_req_enqueue_internal(req);
1630 
1631         /* At this point, the request will be kept alive by the reference
1632          * added by scsi_req_enqueue_internal, so we can release our reference.
1633          * The HBA of course will add its own reference in the load_request
1634          * callback if it needs to hold on the SCSIRequest.
1635          */
1636         scsi_req_unref(req);
1637     }
1638 
1639     return 0;
1640 }
1641 
1642 static const VMStateInfo vmstate_info_scsi_requests = {
1643     .name = "scsi-requests",
1644     .get  = get_scsi_requests,
1645     .put  = put_scsi_requests,
1646 };
1647 
1648 static bool scsi_sense_state_needed(void *opaque)
1649 {
1650     SCSIDevice *s = opaque;
1651 
1652     return s->sense_len > SCSI_SENSE_BUF_SIZE_OLD;
1653 }
1654 
1655 static const VMStateDescription vmstate_scsi_sense_state = {
1656     .name = "SCSIDevice/sense",
1657     .version_id = 1,
1658     .minimum_version_id = 1,
1659     .needed = scsi_sense_state_needed,
1660     .fields = (VMStateField[]) {
1661         VMSTATE_UINT8_SUB_ARRAY(sense, SCSIDevice,
1662                                 SCSI_SENSE_BUF_SIZE_OLD,
1663                                 SCSI_SENSE_BUF_SIZE - SCSI_SENSE_BUF_SIZE_OLD),
1664         VMSTATE_END_OF_LIST()
1665     }
1666 };
1667 
1668 const VMStateDescription vmstate_scsi_device = {
1669     .name = "SCSIDevice",
1670     .version_id = 1,
1671     .minimum_version_id = 1,
1672     .fields = (VMStateField[]) {
1673         VMSTATE_UINT8(unit_attention.key, SCSIDevice),
1674         VMSTATE_UINT8(unit_attention.asc, SCSIDevice),
1675         VMSTATE_UINT8(unit_attention.ascq, SCSIDevice),
1676         VMSTATE_BOOL(sense_is_ua, SCSIDevice),
1677         VMSTATE_UINT8_SUB_ARRAY(sense, SCSIDevice, 0, SCSI_SENSE_BUF_SIZE_OLD),
1678         VMSTATE_UINT32(sense_len, SCSIDevice),
1679         {
1680             .name         = "requests",
1681             .version_id   = 0,
1682             .field_exists = NULL,
1683             .size         = 0,   /* ouch */
1684             .info         = &vmstate_info_scsi_requests,
1685             .flags        = VMS_SINGLE,
1686             .offset       = 0,
1687         },
1688         VMSTATE_END_OF_LIST()
1689     },
1690     .subsections = (const VMStateDescription*[]) {
1691         &vmstate_scsi_sense_state,
1692         NULL
1693     }
1694 };
1695 
1696 static void scsi_device_class_init(ObjectClass *klass, void *data)
1697 {
1698     DeviceClass *k = DEVICE_CLASS(klass);
1699     set_bit(DEVICE_CATEGORY_STORAGE, k->categories);
1700     k->bus_type  = TYPE_SCSI_BUS;
1701     k->realize   = scsi_qdev_realize;
1702     k->unrealize = scsi_qdev_unrealize;
1703     k->props     = scsi_props;
1704 }
1705 
1706 static void scsi_dev_instance_init(Object *obj)
1707 {
1708     DeviceState *dev = DEVICE(obj);
1709     SCSIDevice *s = SCSI_DEVICE(dev);
1710 
1711     device_add_bootindex_property(obj, &s->conf.bootindex,
1712                                   "bootindex", NULL,
1713                                   &s->qdev, NULL);
1714 }
1715 
1716 static const TypeInfo scsi_device_type_info = {
1717     .name = TYPE_SCSI_DEVICE,
1718     .parent = TYPE_DEVICE,
1719     .instance_size = sizeof(SCSIDevice),
1720     .abstract = true,
1721     .class_size = sizeof(SCSIDeviceClass),
1722     .class_init = scsi_device_class_init,
1723     .instance_init = scsi_dev_instance_init,
1724 };
1725 
1726 static void scsi_register_types(void)
1727 {
1728     type_register_static(&scsi_bus_info);
1729     type_register_static(&scsi_device_type_info);
1730 }
1731 
1732 type_init(scsi_register_types)
1733