xref: /openbmc/qemu/hw/scsi/scsi-bus.c (revision 61b01bbc6c27f06f4732aedcb6554e135f41b760)
1 #include "qemu/osdep.h"
2 #include "hw/hw.h"
3 #include "qapi/error.h"
4 #include "qemu/error-report.h"
5 #include "qemu/option.h"
6 #include "hw/scsi/scsi.h"
7 #include "scsi/constants.h"
8 #include "hw/qdev.h"
9 #include "sysemu/block-backend.h"
10 #include "sysemu/blockdev.h"
11 #include "trace.h"
12 #include "sysemu/dma.h"
13 #include "qemu/cutils.h"
14 
15 static char *scsibus_get_dev_path(DeviceState *dev);
16 static char *scsibus_get_fw_dev_path(DeviceState *dev);
17 static void scsi_req_dequeue(SCSIRequest *req);
18 static uint8_t *scsi_target_alloc_buf(SCSIRequest *req, size_t len);
19 static void scsi_target_free_buf(SCSIRequest *req);
20 
21 static Property scsi_props[] = {
22     DEFINE_PROP_UINT32("channel", SCSIDevice, channel, 0),
23     DEFINE_PROP_UINT32("scsi-id", SCSIDevice, id, -1),
24     DEFINE_PROP_UINT32("lun", SCSIDevice, lun, -1),
25     DEFINE_PROP_END_OF_LIST(),
26 };
27 
28 static void scsi_bus_class_init(ObjectClass *klass, void *data)
29 {
30     BusClass *k = BUS_CLASS(klass);
31     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
32 
33     k->get_dev_path = scsibus_get_dev_path;
34     k->get_fw_dev_path = scsibus_get_fw_dev_path;
35     hc->unplug = qdev_simple_device_unplug_cb;
36 }
37 
38 static const TypeInfo scsi_bus_info = {
39     .name = TYPE_SCSI_BUS,
40     .parent = TYPE_BUS,
41     .instance_size = sizeof(SCSIBus),
42     .class_init = scsi_bus_class_init,
43     .interfaces = (InterfaceInfo[]) {
44         { TYPE_HOTPLUG_HANDLER },
45         { }
46     }
47 };
48 static int next_scsi_bus;
49 
50 static void scsi_device_realize(SCSIDevice *s, Error **errp)
51 {
52     SCSIDeviceClass *sc = SCSI_DEVICE_GET_CLASS(s);
53     if (sc->realize) {
54         sc->realize(s, errp);
55     }
56 }
57 
58 int scsi_bus_parse_cdb(SCSIDevice *dev, SCSICommand *cmd, uint8_t *buf,
59                        void *hba_private)
60 {
61     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, dev->qdev.parent_bus);
62     int rc;
63 
64     assert(cmd->len == 0);
65     rc = scsi_req_parse_cdb(dev, cmd, buf);
66     if (bus->info->parse_cdb) {
67         rc = bus->info->parse_cdb(dev, cmd, buf, hba_private);
68     }
69     return rc;
70 }
71 
72 static SCSIRequest *scsi_device_alloc_req(SCSIDevice *s, uint32_t tag, uint32_t lun,
73                                           uint8_t *buf, void *hba_private)
74 {
75     SCSIDeviceClass *sc = SCSI_DEVICE_GET_CLASS(s);
76     if (sc->alloc_req) {
77         return sc->alloc_req(s, tag, lun, buf, hba_private);
78     }
79 
80     return NULL;
81 }
82 
83 void scsi_device_unit_attention_reported(SCSIDevice *s)
84 {
85     SCSIDeviceClass *sc = SCSI_DEVICE_GET_CLASS(s);
86     if (sc->unit_attention_reported) {
87         sc->unit_attention_reported(s);
88     }
89 }
90 
91 /* Create a scsi bus, and attach devices to it.  */
92 void scsi_bus_new(SCSIBus *bus, size_t bus_size, DeviceState *host,
93                   const SCSIBusInfo *info, const char *bus_name)
94 {
95     qbus_create_inplace(bus, bus_size, TYPE_SCSI_BUS, host, bus_name);
96     bus->busnr = next_scsi_bus++;
97     bus->info = info;
98     qbus_set_bus_hotplug_handler(BUS(bus), &error_abort);
99 }
100 
101 static void scsi_dma_restart_bh(void *opaque)
102 {
103     SCSIDevice *s = opaque;
104     SCSIRequest *req, *next;
105 
106     qemu_bh_delete(s->bh);
107     s->bh = NULL;
108 
109     aio_context_acquire(blk_get_aio_context(s->conf.blk));
110     QTAILQ_FOREACH_SAFE(req, &s->requests, next, next) {
111         scsi_req_ref(req);
112         if (req->retry) {
113             req->retry = false;
114             switch (req->cmd.mode) {
115             case SCSI_XFER_FROM_DEV:
116             case SCSI_XFER_TO_DEV:
117                 scsi_req_continue(req);
118                 break;
119             case SCSI_XFER_NONE:
120                 scsi_req_dequeue(req);
121                 scsi_req_enqueue(req);
122                 break;
123             }
124         }
125         scsi_req_unref(req);
126     }
127     aio_context_release(blk_get_aio_context(s->conf.blk));
128 }
129 
130 void scsi_req_retry(SCSIRequest *req)
131 {
132     /* No need to save a reference, because scsi_dma_restart_bh just
133      * looks at the request list.  */
134     req->retry = true;
135 }
136 
137 static void scsi_dma_restart_cb(void *opaque, int running, RunState state)
138 {
139     SCSIDevice *s = opaque;
140 
141     if (!running) {
142         return;
143     }
144     if (!s->bh) {
145         AioContext *ctx = blk_get_aio_context(s->conf.blk);
146         s->bh = aio_bh_new(ctx, scsi_dma_restart_bh, s);
147         qemu_bh_schedule(s->bh);
148     }
149 }
150 
151 static void scsi_qdev_realize(DeviceState *qdev, Error **errp)
152 {
153     SCSIDevice *dev = SCSI_DEVICE(qdev);
154     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, dev->qdev.parent_bus);
155     SCSIDevice *d;
156     Error *local_err = NULL;
157 
158     if (dev->channel > bus->info->max_channel) {
159         error_setg(errp, "bad scsi channel id: %d", dev->channel);
160         return;
161     }
162     if (dev->id != -1 && dev->id > bus->info->max_target) {
163         error_setg(errp, "bad scsi device id: %d", dev->id);
164         return;
165     }
166     if (dev->lun != -1 && dev->lun > bus->info->max_lun) {
167         error_setg(errp, "bad scsi device lun: %d", dev->lun);
168         return;
169     }
170 
171     if (dev->id == -1) {
172         int id = -1;
173         if (dev->lun == -1) {
174             dev->lun = 0;
175         }
176         do {
177             d = scsi_device_find(bus, dev->channel, ++id, dev->lun);
178         } while (d && d->lun == dev->lun && id < bus->info->max_target);
179         if (d && d->lun == dev->lun) {
180             error_setg(errp, "no free target");
181             return;
182         }
183         dev->id = id;
184     } else if (dev->lun == -1) {
185         int lun = -1;
186         do {
187             d = scsi_device_find(bus, dev->channel, dev->id, ++lun);
188         } while (d && d->lun == lun && lun < bus->info->max_lun);
189         if (d && d->lun == lun) {
190             error_setg(errp, "no free lun");
191             return;
192         }
193         dev->lun = lun;
194     } else {
195         d = scsi_device_find(bus, dev->channel, dev->id, dev->lun);
196         assert(d);
197         if (d->lun == dev->lun && dev != d) {
198             error_setg(errp, "lun already used by '%s'", d->qdev.id);
199             return;
200         }
201     }
202 
203     QTAILQ_INIT(&dev->requests);
204     scsi_device_realize(dev, &local_err);
205     if (local_err) {
206         error_propagate(errp, local_err);
207         return;
208     }
209     dev->vmsentry = qemu_add_vm_change_state_handler(scsi_dma_restart_cb,
210                                                      dev);
211 }
212 
213 static void scsi_qdev_unrealize(DeviceState *qdev, Error **errp)
214 {
215     SCSIDevice *dev = SCSI_DEVICE(qdev);
216 
217     if (dev->vmsentry) {
218         qemu_del_vm_change_state_handler(dev->vmsentry);
219     }
220 
221     scsi_device_purge_requests(dev, SENSE_CODE(NO_SENSE));
222     blockdev_mark_auto_del(dev->conf.blk);
223 }
224 
225 /* handle legacy '-drive if=scsi,...' cmd line args */
226 SCSIDevice *scsi_bus_legacy_add_drive(SCSIBus *bus, BlockBackend *blk,
227                                       int unit, bool removable, int bootindex,
228                                       bool share_rw,
229                                       const char *serial, Error **errp)
230 {
231     const char *driver;
232     char *name;
233     DeviceState *dev;
234     Error *err = NULL;
235 
236     driver = blk_is_sg(blk) ? "scsi-generic" : "scsi-disk";
237     dev = qdev_create(&bus->qbus, driver);
238     name = g_strdup_printf("legacy[%d]", unit);
239     object_property_add_child(OBJECT(bus), name, OBJECT(dev), NULL);
240     g_free(name);
241 
242     qdev_prop_set_uint32(dev, "scsi-id", unit);
243     if (bootindex >= 0) {
244         object_property_set_int(OBJECT(dev), bootindex, "bootindex",
245                                 &error_abort);
246     }
247     if (object_property_find(OBJECT(dev), "removable", NULL)) {
248         qdev_prop_set_bit(dev, "removable", removable);
249     }
250     if (serial && object_property_find(OBJECT(dev), "serial", NULL)) {
251         qdev_prop_set_string(dev, "serial", serial);
252     }
253     qdev_prop_set_drive(dev, "drive", blk, &err);
254     if (err) {
255         error_propagate(errp, err);
256         object_unparent(OBJECT(dev));
257         return NULL;
258     }
259     object_property_set_bool(OBJECT(dev), share_rw, "share-rw", &err);
260     if (err != NULL) {
261         error_propagate(errp, err);
262         object_unparent(OBJECT(dev));
263         return NULL;
264     }
265     object_property_set_bool(OBJECT(dev), true, "realized", &err);
266     if (err != NULL) {
267         error_propagate(errp, err);
268         object_unparent(OBJECT(dev));
269         return NULL;
270     }
271     return SCSI_DEVICE(dev);
272 }
273 
274 void scsi_bus_legacy_handle_cmdline(SCSIBus *bus, bool deprecated)
275 {
276     Location loc;
277     DriveInfo *dinfo;
278     int unit;
279 
280     loc_push_none(&loc);
281     for (unit = 0; unit <= bus->info->max_target; unit++) {
282         dinfo = drive_get(IF_SCSI, bus->busnr, unit);
283         if (dinfo == NULL) {
284             continue;
285         }
286         qemu_opts_loc_restore(dinfo->opts);
287         if (deprecated) {
288             /* Handling -drive not claimed by machine initialization */
289             if (blk_get_attached_dev(blk_by_legacy_dinfo(dinfo))) {
290                 continue;       /* claimed */
291             }
292             if (!dinfo->is_default) {
293                 warn_report("bus=%d,unit=%d is deprecated with this"
294                             " machine type",
295                             bus->busnr, unit);
296             }
297         }
298         scsi_bus_legacy_add_drive(bus, blk_by_legacy_dinfo(dinfo),
299                                   unit, false, -1, false, NULL, &error_fatal);
300     }
301     loc_pop(&loc);
302 }
303 
304 static bool is_scsi_hba_with_legacy_magic(Object *obj)
305 {
306     static const char *magic[] = {
307         "am53c974", "dc390", "esp", "lsi53c810", "lsi53c895a",
308         "megasas", "megasas-gen2", "mptsas1068", "spapr-vscsi",
309         "virtio-scsi-device",
310         NULL
311     };
312     const char *typename = object_get_typename(obj);
313     int i;
314 
315     for (i = 0; magic[i]; i++)
316         if (!strcmp(typename, magic[i])) {
317             return true;
318     }
319 
320     return false;
321 }
322 
323 static int scsi_legacy_handle_cmdline_cb(Object *obj, void *opaque)
324 {
325     SCSIBus *bus = (SCSIBus *)object_dynamic_cast(obj, TYPE_SCSI_BUS);
326 
327     if (bus && is_scsi_hba_with_legacy_magic(OBJECT(bus->qbus.parent))) {
328         scsi_bus_legacy_handle_cmdline(bus, true);
329     }
330 
331     return 0;
332 }
333 
334 void scsi_legacy_handle_cmdline(void)
335 {
336     object_child_foreach_recursive(object_get_root(),
337                                    scsi_legacy_handle_cmdline_cb, NULL);
338 }
339 
340 static int32_t scsi_invalid_field(SCSIRequest *req, uint8_t *buf)
341 {
342     scsi_req_build_sense(req, SENSE_CODE(INVALID_FIELD));
343     scsi_req_complete(req, CHECK_CONDITION);
344     return 0;
345 }
346 
347 static const struct SCSIReqOps reqops_invalid_field = {
348     .size         = sizeof(SCSIRequest),
349     .send_command = scsi_invalid_field
350 };
351 
352 /* SCSIReqOps implementation for invalid commands.  */
353 
354 static int32_t scsi_invalid_command(SCSIRequest *req, uint8_t *buf)
355 {
356     scsi_req_build_sense(req, SENSE_CODE(INVALID_OPCODE));
357     scsi_req_complete(req, CHECK_CONDITION);
358     return 0;
359 }
360 
361 static const struct SCSIReqOps reqops_invalid_opcode = {
362     .size         = sizeof(SCSIRequest),
363     .send_command = scsi_invalid_command
364 };
365 
366 /* SCSIReqOps implementation for unit attention conditions.  */
367 
368 static int32_t scsi_unit_attention(SCSIRequest *req, uint8_t *buf)
369 {
370     if (req->dev->unit_attention.key == UNIT_ATTENTION) {
371         scsi_req_build_sense(req, req->dev->unit_attention);
372     } else if (req->bus->unit_attention.key == UNIT_ATTENTION) {
373         scsi_req_build_sense(req, req->bus->unit_attention);
374     }
375     scsi_req_complete(req, CHECK_CONDITION);
376     return 0;
377 }
378 
379 static const struct SCSIReqOps reqops_unit_attention = {
380     .size         = sizeof(SCSIRequest),
381     .send_command = scsi_unit_attention
382 };
383 
384 /* SCSIReqOps implementation for REPORT LUNS and for commands sent to
385    an invalid LUN.  */
386 
387 typedef struct SCSITargetReq SCSITargetReq;
388 
389 struct SCSITargetReq {
390     SCSIRequest req;
391     int len;
392     uint8_t *buf;
393     int buf_len;
394 };
395 
396 static void store_lun(uint8_t *outbuf, int lun)
397 {
398     if (lun < 256) {
399         outbuf[1] = lun;
400         return;
401     }
402     outbuf[1] = (lun & 255);
403     outbuf[0] = (lun >> 8) | 0x40;
404 }
405 
406 static bool scsi_target_emulate_report_luns(SCSITargetReq *r)
407 {
408     BusChild *kid;
409     int i, len, n;
410     int channel, id;
411     bool found_lun0;
412 
413     if (r->req.cmd.xfer < 16) {
414         return false;
415     }
416     if (r->req.cmd.buf[2] > 2) {
417         return false;
418     }
419     channel = r->req.dev->channel;
420     id = r->req.dev->id;
421     found_lun0 = false;
422     n = 0;
423     QTAILQ_FOREACH(kid, &r->req.bus->qbus.children, sibling) {
424         DeviceState *qdev = kid->child;
425         SCSIDevice *dev = SCSI_DEVICE(qdev);
426 
427         if (dev->channel == channel && dev->id == id) {
428             if (dev->lun == 0) {
429                 found_lun0 = true;
430             }
431             n += 8;
432         }
433     }
434     if (!found_lun0) {
435         n += 8;
436     }
437 
438     scsi_target_alloc_buf(&r->req, n + 8);
439 
440     len = MIN(n + 8, r->req.cmd.xfer & ~7);
441     memset(r->buf, 0, len);
442     stl_be_p(&r->buf[0], n);
443     i = found_lun0 ? 8 : 16;
444     QTAILQ_FOREACH(kid, &r->req.bus->qbus.children, sibling) {
445         DeviceState *qdev = kid->child;
446         SCSIDevice *dev = SCSI_DEVICE(qdev);
447 
448         if (dev->channel == channel && dev->id == id) {
449             store_lun(&r->buf[i], dev->lun);
450             i += 8;
451         }
452     }
453     assert(i == n + 8);
454     r->len = len;
455     return true;
456 }
457 
458 static bool scsi_target_emulate_inquiry(SCSITargetReq *r)
459 {
460     assert(r->req.dev->lun != r->req.lun);
461 
462     scsi_target_alloc_buf(&r->req, SCSI_INQUIRY_LEN);
463 
464     if (r->req.cmd.buf[1] & 0x2) {
465         /* Command support data - optional, not implemented */
466         return false;
467     }
468 
469     if (r->req.cmd.buf[1] & 0x1) {
470         /* Vital product data */
471         uint8_t page_code = r->req.cmd.buf[2];
472         r->buf[r->len++] = page_code ; /* this page */
473         r->buf[r->len++] = 0x00;
474 
475         switch (page_code) {
476         case 0x00: /* Supported page codes, mandatory */
477         {
478             int pages;
479             pages = r->len++;
480             r->buf[r->len++] = 0x00; /* list of supported pages (this page) */
481             r->buf[pages] = r->len - pages - 1; /* number of pages */
482             break;
483         }
484         default:
485             return false;
486         }
487         /* done with EVPD */
488         assert(r->len < r->buf_len);
489         r->len = MIN(r->req.cmd.xfer, r->len);
490         return true;
491     }
492 
493     /* Standard INQUIRY data */
494     if (r->req.cmd.buf[2] != 0) {
495         return false;
496     }
497 
498     /* PAGE CODE == 0 */
499     r->len = MIN(r->req.cmd.xfer, SCSI_INQUIRY_LEN);
500     memset(r->buf, 0, r->len);
501     if (r->req.lun != 0) {
502         r->buf[0] = TYPE_NO_LUN;
503     } else {
504         r->buf[0] = TYPE_NOT_PRESENT | TYPE_INACTIVE;
505         r->buf[2] = 5; /* Version */
506         r->buf[3] = 2 | 0x10; /* HiSup, response data format */
507         r->buf[4] = r->len - 5; /* Additional Length = (Len - 1) - 4 */
508         r->buf[7] = 0x10 | (r->req.bus->info->tcq ? 0x02 : 0); /* Sync, TCQ.  */
509         memcpy(&r->buf[8], "QEMU    ", 8);
510         memcpy(&r->buf[16], "QEMU TARGET     ", 16);
511         pstrcpy((char *) &r->buf[32], 4, qemu_hw_version());
512     }
513     return true;
514 }
515 
516 static size_t scsi_sense_len(SCSIRequest *req)
517 {
518     if (req->dev->type == TYPE_SCANNER)
519         return SCSI_SENSE_LEN_SCANNER;
520     else
521         return SCSI_SENSE_LEN;
522 }
523 
524 static int32_t scsi_target_send_command(SCSIRequest *req, uint8_t *buf)
525 {
526     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
527     int fixed_sense = (req->cmd.buf[1] & 1) == 0;
528 
529     if (req->lun != 0 &&
530         buf[0] != INQUIRY && buf[0] != REQUEST_SENSE) {
531         scsi_req_build_sense(req, SENSE_CODE(LUN_NOT_SUPPORTED));
532         scsi_req_complete(req, CHECK_CONDITION);
533         return 0;
534     }
535     switch (buf[0]) {
536     case REPORT_LUNS:
537         if (!scsi_target_emulate_report_luns(r)) {
538             goto illegal_request;
539         }
540         break;
541     case INQUIRY:
542         if (!scsi_target_emulate_inquiry(r)) {
543             goto illegal_request;
544         }
545         break;
546     case REQUEST_SENSE:
547         scsi_target_alloc_buf(&r->req, scsi_sense_len(req));
548         if (req->lun != 0) {
549             const struct SCSISense sense = SENSE_CODE(LUN_NOT_SUPPORTED);
550 
551             r->len = scsi_build_sense_buf(r->buf, req->cmd.xfer,
552                                           sense, fixed_sense);
553         } else {
554             r->len = scsi_device_get_sense(r->req.dev, r->buf,
555                                            MIN(req->cmd.xfer, r->buf_len),
556                                            fixed_sense);
557         }
558         if (r->req.dev->sense_is_ua) {
559             scsi_device_unit_attention_reported(req->dev);
560             r->req.dev->sense_len = 0;
561             r->req.dev->sense_is_ua = false;
562         }
563         break;
564     case TEST_UNIT_READY:
565         break;
566     default:
567         scsi_req_build_sense(req, SENSE_CODE(INVALID_OPCODE));
568         scsi_req_complete(req, CHECK_CONDITION);
569         return 0;
570     illegal_request:
571         scsi_req_build_sense(req, SENSE_CODE(INVALID_FIELD));
572         scsi_req_complete(req, CHECK_CONDITION);
573         return 0;
574     }
575 
576     if (!r->len) {
577         scsi_req_complete(req, GOOD);
578     }
579     return r->len;
580 }
581 
582 static void scsi_target_read_data(SCSIRequest *req)
583 {
584     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
585     uint32_t n;
586 
587     n = r->len;
588     if (n > 0) {
589         r->len = 0;
590         scsi_req_data(&r->req, n);
591     } else {
592         scsi_req_complete(&r->req, GOOD);
593     }
594 }
595 
596 static uint8_t *scsi_target_get_buf(SCSIRequest *req)
597 {
598     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
599 
600     return r->buf;
601 }
602 
603 static uint8_t *scsi_target_alloc_buf(SCSIRequest *req, size_t len)
604 {
605     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
606 
607     r->buf = g_malloc(len);
608     r->buf_len = len;
609 
610     return r->buf;
611 }
612 
613 static void scsi_target_free_buf(SCSIRequest *req)
614 {
615     SCSITargetReq *r = DO_UPCAST(SCSITargetReq, req, req);
616 
617     g_free(r->buf);
618 }
619 
620 static const struct SCSIReqOps reqops_target_command = {
621     .size         = sizeof(SCSITargetReq),
622     .send_command = scsi_target_send_command,
623     .read_data    = scsi_target_read_data,
624     .get_buf      = scsi_target_get_buf,
625     .free_req     = scsi_target_free_buf,
626 };
627 
628 
629 SCSIRequest *scsi_req_alloc(const SCSIReqOps *reqops, SCSIDevice *d,
630                             uint32_t tag, uint32_t lun, void *hba_private)
631 {
632     SCSIRequest *req;
633     SCSIBus *bus = scsi_bus_from_device(d);
634     BusState *qbus = BUS(bus);
635     const int memset_off = offsetof(SCSIRequest, sense)
636                            + sizeof(req->sense);
637 
638     req = g_malloc(reqops->size);
639     memset((uint8_t *)req + memset_off, 0, reqops->size - memset_off);
640     req->refcount = 1;
641     req->bus = bus;
642     req->dev = d;
643     req->tag = tag;
644     req->lun = lun;
645     req->hba_private = hba_private;
646     req->status = -1;
647     req->ops = reqops;
648     object_ref(OBJECT(d));
649     object_ref(OBJECT(qbus->parent));
650     notifier_list_init(&req->cancel_notifiers);
651     trace_scsi_req_alloc(req->dev->id, req->lun, req->tag);
652     return req;
653 }
654 
655 SCSIRequest *scsi_req_new(SCSIDevice *d, uint32_t tag, uint32_t lun,
656                           uint8_t *buf, void *hba_private)
657 {
658     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, d->qdev.parent_bus);
659     const SCSIReqOps *ops;
660     SCSIDeviceClass *sc = SCSI_DEVICE_GET_CLASS(d);
661     SCSIRequest *req;
662     SCSICommand cmd = { .len = 0 };
663     int ret;
664 
665     if ((d->unit_attention.key == UNIT_ATTENTION ||
666          bus->unit_attention.key == UNIT_ATTENTION) &&
667         (buf[0] != INQUIRY &&
668          buf[0] != REPORT_LUNS &&
669          buf[0] != GET_CONFIGURATION &&
670          buf[0] != GET_EVENT_STATUS_NOTIFICATION &&
671 
672          /*
673           * If we already have a pending unit attention condition,
674           * report this one before triggering another one.
675           */
676          !(buf[0] == REQUEST_SENSE && d->sense_is_ua))) {
677         ops = &reqops_unit_attention;
678     } else if (lun != d->lun ||
679                buf[0] == REPORT_LUNS ||
680                (buf[0] == REQUEST_SENSE && d->sense_len)) {
681         ops = &reqops_target_command;
682     } else {
683         ops = NULL;
684     }
685 
686     if (ops != NULL || !sc->parse_cdb) {
687         ret = scsi_req_parse_cdb(d, &cmd, buf);
688     } else {
689         ret = sc->parse_cdb(d, &cmd, buf, hba_private);
690     }
691 
692     if (ret != 0) {
693         trace_scsi_req_parse_bad(d->id, lun, tag, buf[0]);
694         req = scsi_req_alloc(&reqops_invalid_opcode, d, tag, lun, hba_private);
695     } else {
696         assert(cmd.len != 0);
697         trace_scsi_req_parsed(d->id, lun, tag, buf[0],
698                               cmd.mode, cmd.xfer);
699         if (cmd.lba != -1) {
700             trace_scsi_req_parsed_lba(d->id, lun, tag, buf[0],
701                                       cmd.lba);
702         }
703 
704         if (cmd.xfer > INT32_MAX) {
705             req = scsi_req_alloc(&reqops_invalid_field, d, tag, lun, hba_private);
706         } else if (ops) {
707             req = scsi_req_alloc(ops, d, tag, lun, hba_private);
708         } else {
709             req = scsi_device_alloc_req(d, tag, lun, buf, hba_private);
710         }
711     }
712 
713     req->cmd = cmd;
714     req->resid = req->cmd.xfer;
715 
716     switch (buf[0]) {
717     case INQUIRY:
718         trace_scsi_inquiry(d->id, lun, tag, cmd.buf[1], cmd.buf[2]);
719         break;
720     case TEST_UNIT_READY:
721         trace_scsi_test_unit_ready(d->id, lun, tag);
722         break;
723     case REPORT_LUNS:
724         trace_scsi_report_luns(d->id, lun, tag);
725         break;
726     case REQUEST_SENSE:
727         trace_scsi_request_sense(d->id, lun, tag);
728         break;
729     default:
730         break;
731     }
732 
733     return req;
734 }
735 
736 uint8_t *scsi_req_get_buf(SCSIRequest *req)
737 {
738     return req->ops->get_buf(req);
739 }
740 
741 static void scsi_clear_unit_attention(SCSIRequest *req)
742 {
743     SCSISense *ua;
744     if (req->dev->unit_attention.key != UNIT_ATTENTION &&
745         req->bus->unit_attention.key != UNIT_ATTENTION) {
746         return;
747     }
748 
749     /*
750      * If an INQUIRY command enters the enabled command state,
751      * the device server shall [not] clear any unit attention condition;
752      * See also MMC-6, paragraphs 6.5 and 6.6.2.
753      */
754     if (req->cmd.buf[0] == INQUIRY ||
755         req->cmd.buf[0] == GET_CONFIGURATION ||
756         req->cmd.buf[0] == GET_EVENT_STATUS_NOTIFICATION) {
757         return;
758     }
759 
760     if (req->dev->unit_attention.key == UNIT_ATTENTION) {
761         ua = &req->dev->unit_attention;
762     } else {
763         ua = &req->bus->unit_attention;
764     }
765 
766     /*
767      * If a REPORT LUNS command enters the enabled command state, [...]
768      * the device server shall clear any pending unit attention condition
769      * with an additional sense code of REPORTED LUNS DATA HAS CHANGED.
770      */
771     if (req->cmd.buf[0] == REPORT_LUNS &&
772         !(ua->asc == SENSE_CODE(REPORTED_LUNS_CHANGED).asc &&
773           ua->ascq == SENSE_CODE(REPORTED_LUNS_CHANGED).ascq)) {
774         return;
775     }
776 
777     *ua = SENSE_CODE(NO_SENSE);
778 }
779 
780 int scsi_req_get_sense(SCSIRequest *req, uint8_t *buf, int len)
781 {
782     int ret;
783 
784     assert(len >= 14);
785     if (!req->sense_len) {
786         return 0;
787     }
788 
789     ret = scsi_convert_sense(req->sense, req->sense_len, buf, len, true);
790 
791     /*
792      * FIXME: clearing unit attention conditions upon autosense should be done
793      * only if the UA_INTLCK_CTRL field in the Control mode page is set to 00b
794      * (SAM-5, 5.14).
795      *
796      * We assume UA_INTLCK_CTRL to be 00b for HBAs that support autosense, and
797      * 10b for HBAs that do not support it (do not call scsi_req_get_sense).
798      * Here we handle unit attention clearing for UA_INTLCK_CTRL == 00b.
799      */
800     if (req->dev->sense_is_ua) {
801         scsi_device_unit_attention_reported(req->dev);
802         req->dev->sense_len = 0;
803         req->dev->sense_is_ua = false;
804     }
805     return ret;
806 }
807 
808 int scsi_device_get_sense(SCSIDevice *dev, uint8_t *buf, int len, bool fixed)
809 {
810     return scsi_convert_sense(dev->sense, dev->sense_len, buf, len, fixed);
811 }
812 
813 void scsi_req_build_sense(SCSIRequest *req, SCSISense sense)
814 {
815     trace_scsi_req_build_sense(req->dev->id, req->lun, req->tag,
816                                sense.key, sense.asc, sense.ascq);
817     req->sense_len = scsi_build_sense(req->sense, sense);
818 }
819 
820 static void scsi_req_enqueue_internal(SCSIRequest *req)
821 {
822     assert(!req->enqueued);
823     scsi_req_ref(req);
824     if (req->bus->info->get_sg_list) {
825         req->sg = req->bus->info->get_sg_list(req);
826     } else {
827         req->sg = NULL;
828     }
829     req->enqueued = true;
830     QTAILQ_INSERT_TAIL(&req->dev->requests, req, next);
831 }
832 
833 int32_t scsi_req_enqueue(SCSIRequest *req)
834 {
835     int32_t rc;
836 
837     assert(!req->retry);
838     scsi_req_enqueue_internal(req);
839     scsi_req_ref(req);
840     rc = req->ops->send_command(req, req->cmd.buf);
841     scsi_req_unref(req);
842     return rc;
843 }
844 
845 static void scsi_req_dequeue(SCSIRequest *req)
846 {
847     trace_scsi_req_dequeue(req->dev->id, req->lun, req->tag);
848     req->retry = false;
849     if (req->enqueued) {
850         QTAILQ_REMOVE(&req->dev->requests, req, next);
851         req->enqueued = false;
852         scsi_req_unref(req);
853     }
854 }
855 
856 static int scsi_get_performance_length(int num_desc, int type, int data_type)
857 {
858     /* MMC-6, paragraph 6.7.  */
859     switch (type) {
860     case 0:
861         if ((data_type & 3) == 0) {
862             /* Each descriptor is as in Table 295 - Nominal performance.  */
863             return 16 * num_desc + 8;
864         } else {
865             /* Each descriptor is as in Table 296 - Exceptions.  */
866             return 6 * num_desc + 8;
867         }
868     case 1:
869     case 4:
870     case 5:
871         return 8 * num_desc + 8;
872     case 2:
873         return 2048 * num_desc + 8;
874     case 3:
875         return 16 * num_desc + 8;
876     default:
877         return 8;
878     }
879 }
880 
881 static int ata_passthrough_xfer_unit(SCSIDevice *dev, uint8_t *buf)
882 {
883     int byte_block = (buf[2] >> 2) & 0x1;
884     int type = (buf[2] >> 4) & 0x1;
885     int xfer_unit;
886 
887     if (byte_block) {
888         if (type) {
889             xfer_unit = dev->blocksize;
890         } else {
891             xfer_unit = 512;
892         }
893     } else {
894         xfer_unit = 1;
895     }
896 
897     return xfer_unit;
898 }
899 
900 static int ata_passthrough_12_xfer(SCSIDevice *dev, uint8_t *buf)
901 {
902     int length = buf[2] & 0x3;
903     int xfer;
904     int unit = ata_passthrough_xfer_unit(dev, buf);
905 
906     switch (length) {
907     case 0:
908     case 3: /* USB-specific.  */
909     default:
910         xfer = 0;
911         break;
912     case 1:
913         xfer = buf[3];
914         break;
915     case 2:
916         xfer = buf[4];
917         break;
918     }
919 
920     return xfer * unit;
921 }
922 
923 static int ata_passthrough_16_xfer(SCSIDevice *dev, uint8_t *buf)
924 {
925     int extend = buf[1] & 0x1;
926     int length = buf[2] & 0x3;
927     int xfer;
928     int unit = ata_passthrough_xfer_unit(dev, buf);
929 
930     switch (length) {
931     case 0:
932     case 3: /* USB-specific.  */
933     default:
934         xfer = 0;
935         break;
936     case 1:
937         xfer = buf[4];
938         xfer |= (extend ? buf[3] << 8 : 0);
939         break;
940     case 2:
941         xfer = buf[6];
942         xfer |= (extend ? buf[5] << 8 : 0);
943         break;
944     }
945 
946     return xfer * unit;
947 }
948 
949 static int scsi_req_xfer(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
950 {
951     cmd->xfer = scsi_cdb_xfer(buf);
952     switch (buf[0]) {
953     case TEST_UNIT_READY:
954     case REWIND:
955     case START_STOP:
956     case SET_CAPACITY:
957     case WRITE_FILEMARKS:
958     case WRITE_FILEMARKS_16:
959     case SPACE:
960     case RESERVE:
961     case RELEASE:
962     case ERASE:
963     case ALLOW_MEDIUM_REMOVAL:
964     case SEEK_10:
965     case SYNCHRONIZE_CACHE:
966     case SYNCHRONIZE_CACHE_16:
967     case LOCATE_16:
968     case LOCK_UNLOCK_CACHE:
969     case SET_CD_SPEED:
970     case SET_LIMITS:
971     case WRITE_LONG_10:
972     case UPDATE_BLOCK:
973     case RESERVE_TRACK:
974     case SET_READ_AHEAD:
975     case PRE_FETCH:
976     case PRE_FETCH_16:
977     case ALLOW_OVERWRITE:
978         cmd->xfer = 0;
979         break;
980     case VERIFY_10:
981     case VERIFY_12:
982     case VERIFY_16:
983         if ((buf[1] & 2) == 0) {
984             cmd->xfer = 0;
985         } else if ((buf[1] & 4) != 0) {
986             cmd->xfer = 1;
987         }
988         cmd->xfer *= dev->blocksize;
989         break;
990     case MODE_SENSE:
991         break;
992     case WRITE_SAME_10:
993     case WRITE_SAME_16:
994         cmd->xfer = dev->blocksize;
995         break;
996     case READ_CAPACITY_10:
997         cmd->xfer = 8;
998         break;
999     case READ_BLOCK_LIMITS:
1000         cmd->xfer = 6;
1001         break;
1002     case SEND_VOLUME_TAG:
1003         /* GPCMD_SET_STREAMING from multimedia commands.  */
1004         if (dev->type == TYPE_ROM) {
1005             cmd->xfer = buf[10] | (buf[9] << 8);
1006         } else {
1007             cmd->xfer = buf[9] | (buf[8] << 8);
1008         }
1009         break;
1010     case WRITE_6:
1011         /* length 0 means 256 blocks */
1012         if (cmd->xfer == 0) {
1013             cmd->xfer = 256;
1014         }
1015         /* fall through */
1016     case WRITE_10:
1017     case WRITE_VERIFY_10:
1018     case WRITE_12:
1019     case WRITE_VERIFY_12:
1020     case WRITE_16:
1021     case WRITE_VERIFY_16:
1022         cmd->xfer *= dev->blocksize;
1023         break;
1024     case READ_6:
1025     case READ_REVERSE:
1026         /* length 0 means 256 blocks */
1027         if (cmd->xfer == 0) {
1028             cmd->xfer = 256;
1029         }
1030         /* fall through */
1031     case READ_10:
1032     case READ_12:
1033     case READ_16:
1034         cmd->xfer *= dev->blocksize;
1035         break;
1036     case FORMAT_UNIT:
1037         /* MMC mandates the parameter list to be 12-bytes long.  Parameters
1038          * for block devices are restricted to the header right now.  */
1039         if (dev->type == TYPE_ROM && (buf[1] & 16)) {
1040             cmd->xfer = 12;
1041         } else {
1042             cmd->xfer = (buf[1] & 16) == 0 ? 0 : (buf[1] & 32 ? 8 : 4);
1043         }
1044         break;
1045     case INQUIRY:
1046     case RECEIVE_DIAGNOSTIC:
1047     case SEND_DIAGNOSTIC:
1048         cmd->xfer = buf[4] | (buf[3] << 8);
1049         break;
1050     case READ_CD:
1051     case READ_BUFFER:
1052     case WRITE_BUFFER:
1053     case SEND_CUE_SHEET:
1054         cmd->xfer = buf[8] | (buf[7] << 8) | (buf[6] << 16);
1055         break;
1056     case PERSISTENT_RESERVE_OUT:
1057         cmd->xfer = ldl_be_p(&buf[5]) & 0xffffffffULL;
1058         break;
1059     case ERASE_12:
1060         if (dev->type == TYPE_ROM) {
1061             /* MMC command GET PERFORMANCE.  */
1062             cmd->xfer = scsi_get_performance_length(buf[9] | (buf[8] << 8),
1063                                                     buf[10], buf[1] & 0x1f);
1064         }
1065         break;
1066     case MECHANISM_STATUS:
1067     case READ_DVD_STRUCTURE:
1068     case SEND_DVD_STRUCTURE:
1069     case MAINTENANCE_OUT:
1070     case MAINTENANCE_IN:
1071         if (dev->type == TYPE_ROM) {
1072             /* GPCMD_REPORT_KEY and GPCMD_SEND_KEY from multi media commands */
1073             cmd->xfer = buf[9] | (buf[8] << 8);
1074         }
1075         break;
1076     case ATA_PASSTHROUGH_12:
1077         if (dev->type == TYPE_ROM) {
1078             /* BLANK command of MMC */
1079             cmd->xfer = 0;
1080         } else {
1081             cmd->xfer = ata_passthrough_12_xfer(dev, buf);
1082         }
1083         break;
1084     case ATA_PASSTHROUGH_16:
1085         cmd->xfer = ata_passthrough_16_xfer(dev, buf);
1086         break;
1087     }
1088     return 0;
1089 }
1090 
1091 static int scsi_req_stream_xfer(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
1092 {
1093     switch (buf[0]) {
1094     /* stream commands */
1095     case ERASE_12:
1096     case ERASE_16:
1097         cmd->xfer = 0;
1098         break;
1099     case READ_6:
1100     case READ_REVERSE:
1101     case RECOVER_BUFFERED_DATA:
1102     case WRITE_6:
1103         cmd->xfer = buf[4] | (buf[3] << 8) | (buf[2] << 16);
1104         if (buf[1] & 0x01) { /* fixed */
1105             cmd->xfer *= dev->blocksize;
1106         }
1107         break;
1108     case READ_16:
1109     case READ_REVERSE_16:
1110     case VERIFY_16:
1111     case WRITE_16:
1112         cmd->xfer = buf[14] | (buf[13] << 8) | (buf[12] << 16);
1113         if (buf[1] & 0x01) { /* fixed */
1114             cmd->xfer *= dev->blocksize;
1115         }
1116         break;
1117     case REWIND:
1118     case LOAD_UNLOAD:
1119         cmd->xfer = 0;
1120         break;
1121     case SPACE_16:
1122         cmd->xfer = buf[13] | (buf[12] << 8);
1123         break;
1124     case READ_POSITION:
1125         switch (buf[1] & 0x1f) /* operation code */ {
1126         case SHORT_FORM_BLOCK_ID:
1127         case SHORT_FORM_VENDOR_SPECIFIC:
1128             cmd->xfer = 20;
1129             break;
1130         case LONG_FORM:
1131             cmd->xfer = 32;
1132             break;
1133         case EXTENDED_FORM:
1134             cmd->xfer = buf[8] | (buf[7] << 8);
1135             break;
1136         default:
1137             return -1;
1138         }
1139 
1140         break;
1141     case FORMAT_UNIT:
1142         cmd->xfer = buf[4] | (buf[3] << 8);
1143         break;
1144     /* generic commands */
1145     default:
1146         return scsi_req_xfer(cmd, dev, buf);
1147     }
1148     return 0;
1149 }
1150 
1151 static int scsi_req_medium_changer_xfer(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
1152 {
1153     switch (buf[0]) {
1154     /* medium changer commands */
1155     case EXCHANGE_MEDIUM:
1156     case INITIALIZE_ELEMENT_STATUS:
1157     case INITIALIZE_ELEMENT_STATUS_WITH_RANGE:
1158     case MOVE_MEDIUM:
1159     case POSITION_TO_ELEMENT:
1160         cmd->xfer = 0;
1161         break;
1162     case READ_ELEMENT_STATUS:
1163         cmd->xfer = buf[9] | (buf[8] << 8) | (buf[7] << 16);
1164         break;
1165 
1166     /* generic commands */
1167     default:
1168         return scsi_req_xfer(cmd, dev, buf);
1169     }
1170     return 0;
1171 }
1172 
1173 static int scsi_req_scanner_length(SCSICommand *cmd, SCSIDevice *dev, uint8_t *buf)
1174 {
1175     switch (buf[0]) {
1176     /* Scanner commands */
1177     case OBJECT_POSITION:
1178         cmd->xfer = 0;
1179         break;
1180     case SCAN:
1181         cmd->xfer = buf[4];
1182         break;
1183     case READ_10:
1184     case SEND:
1185     case GET_WINDOW:
1186     case SET_WINDOW:
1187         cmd->xfer = buf[8] | (buf[7] << 8) | (buf[6] << 16);
1188         break;
1189     default:
1190         /* GET_DATA_BUFFER_STATUS xfer handled by scsi_req_xfer */
1191         return scsi_req_xfer(cmd, dev, buf);
1192     }
1193 
1194     return 0;
1195 }
1196 
1197 static void scsi_cmd_xfer_mode(SCSICommand *cmd)
1198 {
1199     if (!cmd->xfer) {
1200         cmd->mode = SCSI_XFER_NONE;
1201         return;
1202     }
1203     switch (cmd->buf[0]) {
1204     case WRITE_6:
1205     case WRITE_10:
1206     case WRITE_VERIFY_10:
1207     case WRITE_12:
1208     case WRITE_VERIFY_12:
1209     case WRITE_16:
1210     case WRITE_VERIFY_16:
1211     case VERIFY_10:
1212     case VERIFY_12:
1213     case VERIFY_16:
1214     case COPY:
1215     case COPY_VERIFY:
1216     case COMPARE:
1217     case CHANGE_DEFINITION:
1218     case LOG_SELECT:
1219     case MODE_SELECT:
1220     case MODE_SELECT_10:
1221     case SEND_DIAGNOSTIC:
1222     case WRITE_BUFFER:
1223     case FORMAT_UNIT:
1224     case REASSIGN_BLOCKS:
1225     case SEARCH_EQUAL:
1226     case SEARCH_HIGH:
1227     case SEARCH_LOW:
1228     case UPDATE_BLOCK:
1229     case WRITE_LONG_10:
1230     case WRITE_SAME_10:
1231     case WRITE_SAME_16:
1232     case UNMAP:
1233     case SEARCH_HIGH_12:
1234     case SEARCH_EQUAL_12:
1235     case SEARCH_LOW_12:
1236     case MEDIUM_SCAN:
1237     case SEND_VOLUME_TAG:
1238     case SEND_CUE_SHEET:
1239     case SEND_DVD_STRUCTURE:
1240     case PERSISTENT_RESERVE_OUT:
1241     case MAINTENANCE_OUT:
1242     case SET_WINDOW:
1243     case SCAN:
1244         /* SCAN conflicts with START_STOP.  START_STOP has cmd->xfer set to 0 for
1245          * non-scanner devices, so we only get here for SCAN and not for START_STOP.
1246          */
1247         cmd->mode = SCSI_XFER_TO_DEV;
1248         break;
1249     case ATA_PASSTHROUGH_12:
1250     case ATA_PASSTHROUGH_16:
1251         /* T_DIR */
1252         cmd->mode = (cmd->buf[2] & 0x8) ?
1253                    SCSI_XFER_FROM_DEV : SCSI_XFER_TO_DEV;
1254         break;
1255     default:
1256         cmd->mode = SCSI_XFER_FROM_DEV;
1257         break;
1258     }
1259 }
1260 
1261 int scsi_req_parse_cdb(SCSIDevice *dev, SCSICommand *cmd, uint8_t *buf)
1262 {
1263     int rc;
1264     int len;
1265 
1266     cmd->lba = -1;
1267     len = scsi_cdb_length(buf);
1268     if (len < 0) {
1269         return -1;
1270     }
1271 
1272     cmd->len = len;
1273     switch (dev->type) {
1274     case TYPE_TAPE:
1275         rc = scsi_req_stream_xfer(cmd, dev, buf);
1276         break;
1277     case TYPE_MEDIUM_CHANGER:
1278         rc = scsi_req_medium_changer_xfer(cmd, dev, buf);
1279         break;
1280     case TYPE_SCANNER:
1281         rc = scsi_req_scanner_length(cmd, dev, buf);
1282         break;
1283     default:
1284         rc = scsi_req_xfer(cmd, dev, buf);
1285         break;
1286     }
1287 
1288     if (rc != 0)
1289         return rc;
1290 
1291     memcpy(cmd->buf, buf, cmd->len);
1292     scsi_cmd_xfer_mode(cmd);
1293     cmd->lba = scsi_cmd_lba(cmd);
1294     return 0;
1295 }
1296 
1297 void scsi_device_report_change(SCSIDevice *dev, SCSISense sense)
1298 {
1299     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, dev->qdev.parent_bus);
1300 
1301     scsi_device_set_ua(dev, sense);
1302     if (bus->info->change) {
1303         bus->info->change(bus, dev, sense);
1304     }
1305 }
1306 
1307 SCSIRequest *scsi_req_ref(SCSIRequest *req)
1308 {
1309     assert(req->refcount > 0);
1310     req->refcount++;
1311     return req;
1312 }
1313 
1314 void scsi_req_unref(SCSIRequest *req)
1315 {
1316     assert(req->refcount > 0);
1317     if (--req->refcount == 0) {
1318         BusState *qbus = req->dev->qdev.parent_bus;
1319         SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, qbus);
1320 
1321         if (bus->info->free_request && req->hba_private) {
1322             bus->info->free_request(bus, req->hba_private);
1323         }
1324         if (req->ops->free_req) {
1325             req->ops->free_req(req);
1326         }
1327         object_unref(OBJECT(req->dev));
1328         object_unref(OBJECT(qbus->parent));
1329         g_free(req);
1330     }
1331 }
1332 
1333 /* Tell the device that we finished processing this chunk of I/O.  It
1334    will start the next chunk or complete the command.  */
1335 void scsi_req_continue(SCSIRequest *req)
1336 {
1337     if (req->io_canceled) {
1338         trace_scsi_req_continue_canceled(req->dev->id, req->lun, req->tag);
1339         return;
1340     }
1341     trace_scsi_req_continue(req->dev->id, req->lun, req->tag);
1342     if (req->cmd.mode == SCSI_XFER_TO_DEV) {
1343         req->ops->write_data(req);
1344     } else {
1345         req->ops->read_data(req);
1346     }
1347 }
1348 
1349 /* Called by the devices when data is ready for the HBA.  The HBA should
1350    start a DMA operation to read or fill the device's data buffer.
1351    Once it completes, calling scsi_req_continue will restart I/O.  */
1352 void scsi_req_data(SCSIRequest *req, int len)
1353 {
1354     uint8_t *buf;
1355     if (req->io_canceled) {
1356         trace_scsi_req_data_canceled(req->dev->id, req->lun, req->tag, len);
1357         return;
1358     }
1359     trace_scsi_req_data(req->dev->id, req->lun, req->tag, len);
1360     assert(req->cmd.mode != SCSI_XFER_NONE);
1361     if (!req->sg) {
1362         req->resid -= len;
1363         req->bus->info->transfer_data(req, len);
1364         return;
1365     }
1366 
1367     /* If the device calls scsi_req_data and the HBA specified a
1368      * scatter/gather list, the transfer has to happen in a single
1369      * step.  */
1370     assert(!req->dma_started);
1371     req->dma_started = true;
1372 
1373     buf = scsi_req_get_buf(req);
1374     if (req->cmd.mode == SCSI_XFER_FROM_DEV) {
1375         req->resid = dma_buf_read(buf, len, req->sg);
1376     } else {
1377         req->resid = dma_buf_write(buf, len, req->sg);
1378     }
1379     scsi_req_continue(req);
1380 }
1381 
1382 void scsi_req_print(SCSIRequest *req)
1383 {
1384     FILE *fp = stderr;
1385     int i;
1386 
1387     fprintf(fp, "[%s id=%d] %s",
1388             req->dev->qdev.parent_bus->name,
1389             req->dev->id,
1390             scsi_command_name(req->cmd.buf[0]));
1391     for (i = 1; i < req->cmd.len; i++) {
1392         fprintf(fp, " 0x%02x", req->cmd.buf[i]);
1393     }
1394     switch (req->cmd.mode) {
1395     case SCSI_XFER_NONE:
1396         fprintf(fp, " - none\n");
1397         break;
1398     case SCSI_XFER_FROM_DEV:
1399         fprintf(fp, " - from-dev len=%zd\n", req->cmd.xfer);
1400         break;
1401     case SCSI_XFER_TO_DEV:
1402         fprintf(fp, " - to-dev len=%zd\n", req->cmd.xfer);
1403         break;
1404     default:
1405         fprintf(fp, " - Oops\n");
1406         break;
1407     }
1408 }
1409 
1410 void scsi_req_complete(SCSIRequest *req, int status)
1411 {
1412     assert(req->status == -1);
1413     req->status = status;
1414 
1415     assert(req->sense_len <= sizeof(req->sense));
1416     if (status == GOOD) {
1417         req->sense_len = 0;
1418     }
1419 
1420     if (req->sense_len) {
1421         memcpy(req->dev->sense, req->sense, req->sense_len);
1422         req->dev->sense_len = req->sense_len;
1423         req->dev->sense_is_ua = (req->ops == &reqops_unit_attention);
1424     } else {
1425         req->dev->sense_len = 0;
1426         req->dev->sense_is_ua = false;
1427     }
1428 
1429     /*
1430      * Unit attention state is now stored in the device's sense buffer
1431      * if the HBA didn't do autosense.  Clear the pending unit attention
1432      * flags.
1433      */
1434     scsi_clear_unit_attention(req);
1435 
1436     scsi_req_ref(req);
1437     scsi_req_dequeue(req);
1438     req->bus->info->complete(req, req->status, req->resid);
1439 
1440     /* Cancelled requests might end up being completed instead of cancelled */
1441     notifier_list_notify(&req->cancel_notifiers, req);
1442     scsi_req_unref(req);
1443 }
1444 
1445 /* Called by the devices when the request is canceled. */
1446 void scsi_req_cancel_complete(SCSIRequest *req)
1447 {
1448     assert(req->io_canceled);
1449     if (req->bus->info->cancel) {
1450         req->bus->info->cancel(req);
1451     }
1452     notifier_list_notify(&req->cancel_notifiers, req);
1453     scsi_req_unref(req);
1454 }
1455 
1456 /* Cancel @req asynchronously. @notifier is added to @req's cancellation
1457  * notifier list, the bus will be notified the requests cancellation is
1458  * completed.
1459  * */
1460 void scsi_req_cancel_async(SCSIRequest *req, Notifier *notifier)
1461 {
1462     trace_scsi_req_cancel(req->dev->id, req->lun, req->tag);
1463     if (notifier) {
1464         notifier_list_add(&req->cancel_notifiers, notifier);
1465     }
1466     if (req->io_canceled) {
1467         /* A blk_aio_cancel_async is pending; when it finishes,
1468          * scsi_req_cancel_complete will be called and will
1469          * call the notifier we just added.  Just wait for that.
1470          */
1471         assert(req->aiocb);
1472         return;
1473     }
1474     /* Dropped in scsi_req_cancel_complete.  */
1475     scsi_req_ref(req);
1476     scsi_req_dequeue(req);
1477     req->io_canceled = true;
1478     if (req->aiocb) {
1479         blk_aio_cancel_async(req->aiocb);
1480     } else {
1481         scsi_req_cancel_complete(req);
1482     }
1483 }
1484 
1485 void scsi_req_cancel(SCSIRequest *req)
1486 {
1487     trace_scsi_req_cancel(req->dev->id, req->lun, req->tag);
1488     if (!req->enqueued) {
1489         return;
1490     }
1491     assert(!req->io_canceled);
1492     /* Dropped in scsi_req_cancel_complete.  */
1493     scsi_req_ref(req);
1494     scsi_req_dequeue(req);
1495     req->io_canceled = true;
1496     if (req->aiocb) {
1497         blk_aio_cancel(req->aiocb);
1498     } else {
1499         scsi_req_cancel_complete(req);
1500     }
1501 }
1502 
1503 static int scsi_ua_precedence(SCSISense sense)
1504 {
1505     if (sense.key != UNIT_ATTENTION) {
1506         return INT_MAX;
1507     }
1508     if (sense.asc == 0x29 && sense.ascq == 0x04) {
1509         /* DEVICE INTERNAL RESET goes with POWER ON OCCURRED */
1510         return 1;
1511     } else if (sense.asc == 0x3F && sense.ascq == 0x01) {
1512         /* MICROCODE HAS BEEN CHANGED goes with SCSI BUS RESET OCCURRED */
1513         return 2;
1514     } else if (sense.asc == 0x29 && (sense.ascq == 0x05 || sense.ascq == 0x06)) {
1515         /* These two go with "all others". */
1516         ;
1517     } else if (sense.asc == 0x29 && sense.ascq <= 0x07) {
1518         /* POWER ON, RESET OR BUS DEVICE RESET OCCURRED = 0
1519          * POWER ON OCCURRED = 1
1520          * SCSI BUS RESET OCCURRED = 2
1521          * BUS DEVICE RESET FUNCTION OCCURRED = 3
1522          * I_T NEXUS LOSS OCCURRED = 7
1523          */
1524         return sense.ascq;
1525     } else if (sense.asc == 0x2F && sense.ascq == 0x01) {
1526         /* COMMANDS CLEARED BY POWER LOSS NOTIFICATION  */
1527         return 8;
1528     }
1529     return (sense.asc << 8) | sense.ascq;
1530 }
1531 
1532 void scsi_device_set_ua(SCSIDevice *sdev, SCSISense sense)
1533 {
1534     int prec1, prec2;
1535     if (sense.key != UNIT_ATTENTION) {
1536         return;
1537     }
1538     trace_scsi_device_set_ua(sdev->id, sdev->lun, sense.key,
1539                              sense.asc, sense.ascq);
1540 
1541     /*
1542      * Override a pre-existing unit attention condition, except for a more
1543      * important reset condition.
1544     */
1545     prec1 = scsi_ua_precedence(sdev->unit_attention);
1546     prec2 = scsi_ua_precedence(sense);
1547     if (prec2 < prec1) {
1548         sdev->unit_attention = sense;
1549     }
1550 }
1551 
1552 void scsi_device_purge_requests(SCSIDevice *sdev, SCSISense sense)
1553 {
1554     SCSIRequest *req;
1555 
1556     aio_context_acquire(blk_get_aio_context(sdev->conf.blk));
1557     while (!QTAILQ_EMPTY(&sdev->requests)) {
1558         req = QTAILQ_FIRST(&sdev->requests);
1559         scsi_req_cancel_async(req, NULL);
1560     }
1561     blk_drain(sdev->conf.blk);
1562     aio_context_release(blk_get_aio_context(sdev->conf.blk));
1563     scsi_device_set_ua(sdev, sense);
1564 }
1565 
1566 static char *scsibus_get_dev_path(DeviceState *dev)
1567 {
1568     SCSIDevice *d = SCSI_DEVICE(dev);
1569     DeviceState *hba = dev->parent_bus->parent;
1570     char *id;
1571     char *path;
1572 
1573     id = qdev_get_dev_path(hba);
1574     if (id) {
1575         path = g_strdup_printf("%s/%d:%d:%d", id, d->channel, d->id, d->lun);
1576     } else {
1577         path = g_strdup_printf("%d:%d:%d", d->channel, d->id, d->lun);
1578     }
1579     g_free(id);
1580     return path;
1581 }
1582 
1583 static char *scsibus_get_fw_dev_path(DeviceState *dev)
1584 {
1585     SCSIDevice *d = SCSI_DEVICE(dev);
1586     return g_strdup_printf("channel@%x/%s@%x,%x", d->channel,
1587                            qdev_fw_name(dev), d->id, d->lun);
1588 }
1589 
1590 SCSIDevice *scsi_device_find(SCSIBus *bus, int channel, int id, int lun)
1591 {
1592     BusChild *kid;
1593     SCSIDevice *target_dev = NULL;
1594 
1595     QTAILQ_FOREACH_REVERSE(kid, &bus->qbus.children, ChildrenHead, sibling) {
1596         DeviceState *qdev = kid->child;
1597         SCSIDevice *dev = SCSI_DEVICE(qdev);
1598 
1599         if (dev->channel == channel && dev->id == id) {
1600             if (dev->lun == lun) {
1601                 return dev;
1602             }
1603             target_dev = dev;
1604         }
1605     }
1606     return target_dev;
1607 }
1608 
1609 /* SCSI request list.  For simplicity, pv points to the whole device */
1610 
1611 static int put_scsi_requests(QEMUFile *f, void *pv, size_t size,
1612                              VMStateField *field, QJSON *vmdesc)
1613 {
1614     SCSIDevice *s = pv;
1615     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, s->qdev.parent_bus);
1616     SCSIRequest *req;
1617 
1618     QTAILQ_FOREACH(req, &s->requests, next) {
1619         assert(!req->io_canceled);
1620         assert(req->status == -1);
1621         assert(req->enqueued);
1622 
1623         qemu_put_sbyte(f, req->retry ? 1 : 2);
1624         qemu_put_buffer(f, req->cmd.buf, sizeof(req->cmd.buf));
1625         qemu_put_be32s(f, &req->tag);
1626         qemu_put_be32s(f, &req->lun);
1627         if (bus->info->save_request) {
1628             bus->info->save_request(f, req);
1629         }
1630         if (req->ops->save_request) {
1631             req->ops->save_request(f, req);
1632         }
1633     }
1634     qemu_put_sbyte(f, 0);
1635 
1636     return 0;
1637 }
1638 
1639 static int get_scsi_requests(QEMUFile *f, void *pv, size_t size,
1640                              VMStateField *field)
1641 {
1642     SCSIDevice *s = pv;
1643     SCSIBus *bus = DO_UPCAST(SCSIBus, qbus, s->qdev.parent_bus);
1644     int8_t sbyte;
1645 
1646     while ((sbyte = qemu_get_sbyte(f)) > 0) {
1647         uint8_t buf[SCSI_CMD_BUF_SIZE];
1648         uint32_t tag;
1649         uint32_t lun;
1650         SCSIRequest *req;
1651 
1652         qemu_get_buffer(f, buf, sizeof(buf));
1653         qemu_get_be32s(f, &tag);
1654         qemu_get_be32s(f, &lun);
1655         req = scsi_req_new(s, tag, lun, buf, NULL);
1656         req->retry = (sbyte == 1);
1657         if (bus->info->load_request) {
1658             req->hba_private = bus->info->load_request(f, req);
1659         }
1660         if (req->ops->load_request) {
1661             req->ops->load_request(f, req);
1662         }
1663 
1664         /* Just restart it later.  */
1665         scsi_req_enqueue_internal(req);
1666 
1667         /* At this point, the request will be kept alive by the reference
1668          * added by scsi_req_enqueue_internal, so we can release our reference.
1669          * The HBA of course will add its own reference in the load_request
1670          * callback if it needs to hold on the SCSIRequest.
1671          */
1672         scsi_req_unref(req);
1673     }
1674 
1675     return 0;
1676 }
1677 
1678 static const VMStateInfo vmstate_info_scsi_requests = {
1679     .name = "scsi-requests",
1680     .get  = get_scsi_requests,
1681     .put  = put_scsi_requests,
1682 };
1683 
1684 static bool scsi_sense_state_needed(void *opaque)
1685 {
1686     SCSIDevice *s = opaque;
1687 
1688     return s->sense_len > SCSI_SENSE_BUF_SIZE_OLD;
1689 }
1690 
1691 static const VMStateDescription vmstate_scsi_sense_state = {
1692     .name = "SCSIDevice/sense",
1693     .version_id = 1,
1694     .minimum_version_id = 1,
1695     .needed = scsi_sense_state_needed,
1696     .fields = (VMStateField[]) {
1697         VMSTATE_UINT8_SUB_ARRAY(sense, SCSIDevice,
1698                                 SCSI_SENSE_BUF_SIZE_OLD,
1699                                 SCSI_SENSE_BUF_SIZE - SCSI_SENSE_BUF_SIZE_OLD),
1700         VMSTATE_END_OF_LIST()
1701     }
1702 };
1703 
1704 const VMStateDescription vmstate_scsi_device = {
1705     .name = "SCSIDevice",
1706     .version_id = 1,
1707     .minimum_version_id = 1,
1708     .fields = (VMStateField[]) {
1709         VMSTATE_UINT8(unit_attention.key, SCSIDevice),
1710         VMSTATE_UINT8(unit_attention.asc, SCSIDevice),
1711         VMSTATE_UINT8(unit_attention.ascq, SCSIDevice),
1712         VMSTATE_BOOL(sense_is_ua, SCSIDevice),
1713         VMSTATE_UINT8_SUB_ARRAY(sense, SCSIDevice, 0, SCSI_SENSE_BUF_SIZE_OLD),
1714         VMSTATE_UINT32(sense_len, SCSIDevice),
1715         {
1716             .name         = "requests",
1717             .version_id   = 0,
1718             .field_exists = NULL,
1719             .size         = 0,   /* ouch */
1720             .info         = &vmstate_info_scsi_requests,
1721             .flags        = VMS_SINGLE,
1722             .offset       = 0,
1723         },
1724         VMSTATE_END_OF_LIST()
1725     },
1726     .subsections = (const VMStateDescription*[]) {
1727         &vmstate_scsi_sense_state,
1728         NULL
1729     }
1730 };
1731 
1732 static void scsi_device_class_init(ObjectClass *klass, void *data)
1733 {
1734     DeviceClass *k = DEVICE_CLASS(klass);
1735     set_bit(DEVICE_CATEGORY_STORAGE, k->categories);
1736     k->bus_type  = TYPE_SCSI_BUS;
1737     k->realize   = scsi_qdev_realize;
1738     k->unrealize = scsi_qdev_unrealize;
1739     k->props     = scsi_props;
1740 }
1741 
1742 static void scsi_dev_instance_init(Object *obj)
1743 {
1744     DeviceState *dev = DEVICE(obj);
1745     SCSIDevice *s = SCSI_DEVICE(dev);
1746 
1747     device_add_bootindex_property(obj, &s->conf.bootindex,
1748                                   "bootindex", NULL,
1749                                   &s->qdev, NULL);
1750 }
1751 
1752 static const TypeInfo scsi_device_type_info = {
1753     .name = TYPE_SCSI_DEVICE,
1754     .parent = TYPE_DEVICE,
1755     .instance_size = sizeof(SCSIDevice),
1756     .abstract = true,
1757     .class_size = sizeof(SCSIDeviceClass),
1758     .class_init = scsi_device_class_init,
1759     .instance_init = scsi_dev_instance_init,
1760 };
1761 
1762 static void scsi_register_types(void)
1763 {
1764     type_register_static(&scsi_bus_info);
1765     type_register_static(&scsi_device_type_info);
1766 }
1767 
1768 type_init(scsi_register_types)
1769