xref: /qemu/hw/usb/dev-uas.c (revision a372823a)
1 /*
2  * UAS (USB Attached SCSI) emulation
3  *
4  * Copyright Red Hat, Inc. 2012
5  *
6  * Author: Gerd Hoffmann <kraxel@redhat.com>
7  *
8  * This work is licensed under the terms of the GNU GPL, version 2 or later.
9  * See the COPYING file in the top-level directory.
10  */
11 
12 #include "qemu-common.h"
13 #include "qemu/option.h"
14 #include "qemu/config-file.h"
15 #include "trace.h"
16 
17 #include "hw/usb.h"
18 #include "hw/usb/desc.h"
19 #include "hw/scsi.h"
20 #include "hw/scsi-defs.h"
21 
22 /* --------------------------------------------------------------------- */
23 
24 #define UAS_UI_COMMAND              0x01
25 #define UAS_UI_SENSE                0x03
26 #define UAS_UI_RESPONSE             0x04
27 #define UAS_UI_TASK_MGMT            0x05
28 #define UAS_UI_READ_READY           0x06
29 #define UAS_UI_WRITE_READY          0x07
30 
31 #define UAS_RC_TMF_COMPLETE         0x00
32 #define UAS_RC_INVALID_INFO_UNIT    0x02
33 #define UAS_RC_TMF_NOT_SUPPORTED    0x04
34 #define UAS_RC_TMF_FAILED           0x05
35 #define UAS_RC_TMF_SUCCEEDED        0x08
36 #define UAS_RC_INCORRECT_LUN        0x09
37 #define UAS_RC_OVERLAPPED_TAG       0x0a
38 
39 #define UAS_TMF_ABORT_TASK          0x01
40 #define UAS_TMF_ABORT_TASK_SET      0x02
41 #define UAS_TMF_CLEAR_TASK_SET      0x04
42 #define UAS_TMF_LOGICAL_UNIT_RESET  0x08
43 #define UAS_TMF_I_T_NEXUS_RESET     0x10
44 #define UAS_TMF_CLEAR_ACA           0x40
45 #define UAS_TMF_QUERY_TASK          0x80
46 #define UAS_TMF_QUERY_TASK_SET      0x81
47 #define UAS_TMF_QUERY_ASYNC_EVENT   0x82
48 
49 #define UAS_PIPE_ID_COMMAND         0x01
50 #define UAS_PIPE_ID_STATUS          0x02
51 #define UAS_PIPE_ID_DATA_IN         0x03
52 #define UAS_PIPE_ID_DATA_OUT        0x04
53 
54 typedef struct {
55     uint8_t    id;
56     uint8_t    reserved;
57     uint16_t   tag;
58 } QEMU_PACKED  uas_ui_header;
59 
60 typedef struct {
61     uint8_t    prio_taskattr;   /* 6:3 priority, 2:0 task attribute   */
62     uint8_t    reserved_1;
63     uint8_t    add_cdb_length;  /* 7:2 additional adb length (dwords) */
64     uint8_t    reserved_2;
65     uint64_t   lun;
66     uint8_t    cdb[16];
67     uint8_t    add_cdb[];
68 } QEMU_PACKED  uas_ui_command;
69 
70 typedef struct {
71     uint16_t   status_qualifier;
72     uint8_t    status;
73     uint8_t    reserved[7];
74     uint16_t   sense_length;
75     uint8_t    sense_data[18];
76 } QEMU_PACKED  uas_ui_sense;
77 
78 typedef struct {
79     uint16_t   add_response_info;
80     uint8_t    response_code;
81 } QEMU_PACKED  uas_ui_response;
82 
83 typedef struct {
84     uint8_t    function;
85     uint8_t    reserved;
86     uint16_t   task_tag;
87     uint64_t   lun;
88 } QEMU_PACKED  uas_ui_task_mgmt;
89 
90 typedef struct {
91     uas_ui_header  hdr;
92     union {
93         uas_ui_command   command;
94         uas_ui_sense     sense;
95         uas_ui_task_mgmt task;
96         uas_ui_response  response;
97     };
98 } QEMU_PACKED  uas_ui;
99 
100 /* --------------------------------------------------------------------- */
101 
102 typedef struct UASDevice UASDevice;
103 typedef struct UASRequest UASRequest;
104 typedef struct UASStatus UASStatus;
105 
106 struct UASDevice {
107     USBDevice                 dev;
108     SCSIBus                   bus;
109     UASRequest                *datain;
110     UASRequest                *dataout;
111     USBPacket                 *status;
112     QEMUBH                    *status_bh;
113     QTAILQ_HEAD(, UASStatus)  results;
114     QTAILQ_HEAD(, UASRequest) requests;
115 };
116 
117 struct UASRequest {
118     uint16_t     tag;
119     uint64_t     lun;
120     UASDevice    *uas;
121     SCSIDevice   *dev;
122     SCSIRequest  *req;
123     USBPacket    *data;
124     bool         data_async;
125     bool         active;
126     bool         complete;
127     uint32_t     buf_off;
128     uint32_t     buf_size;
129     uint32_t     data_off;
130     uint32_t     data_size;
131     QTAILQ_ENTRY(UASRequest)  next;
132 };
133 
134 struct UASStatus {
135     uas_ui                    status;
136     uint32_t                  length;
137     QTAILQ_ENTRY(UASStatus)   next;
138 };
139 
140 /* --------------------------------------------------------------------- */
141 
142 enum {
143     STR_MANUFACTURER = 1,
144     STR_PRODUCT,
145     STR_SERIALNUMBER,
146     STR_CONFIG_HIGH,
147 };
148 
149 static const USBDescStrings desc_strings = {
150     [STR_MANUFACTURER] = "QEMU",
151     [STR_PRODUCT]      = "USB Attached SCSI HBA",
152     [STR_SERIALNUMBER] = "27842",
153     [STR_CONFIG_HIGH]  = "High speed config (usb 2.0)",
154 };
155 
156 static const USBDescIface desc_iface_high = {
157     .bInterfaceNumber              = 0,
158     .bNumEndpoints                 = 4,
159     .bInterfaceClass               = USB_CLASS_MASS_STORAGE,
160     .bInterfaceSubClass            = 0x06, /* SCSI */
161     .bInterfaceProtocol            = 0x62, /* UAS  */
162     .eps = (USBDescEndpoint[]) {
163         {
164             .bEndpointAddress      = USB_DIR_OUT | UAS_PIPE_ID_COMMAND,
165             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
166             .wMaxPacketSize        = 512,
167             .extra = (uint8_t[]) {
168                 0x04,  /*  u8  bLength */
169                 0x24,  /*  u8  bDescriptorType */
170                 UAS_PIPE_ID_COMMAND,
171                 0x00,  /*  u8  bReserved */
172             },
173         },{
174             .bEndpointAddress      = USB_DIR_IN | UAS_PIPE_ID_STATUS,
175             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
176             .wMaxPacketSize        = 512,
177             .extra = (uint8_t[]) {
178                 0x04,  /*  u8  bLength */
179                 0x24,  /*  u8  bDescriptorType */
180                 UAS_PIPE_ID_STATUS,
181                 0x00,  /*  u8  bReserved */
182             },
183         },{
184             .bEndpointAddress      = USB_DIR_IN | UAS_PIPE_ID_DATA_IN,
185             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
186             .wMaxPacketSize        = 512,
187             .extra = (uint8_t[]) {
188                 0x04,  /*  u8  bLength */
189                 0x24,  /*  u8  bDescriptorType */
190                 UAS_PIPE_ID_DATA_IN,
191                 0x00,  /*  u8  bReserved */
192             },
193         },{
194             .bEndpointAddress      = USB_DIR_OUT | UAS_PIPE_ID_DATA_OUT,
195             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
196             .wMaxPacketSize        = 512,
197             .extra = (uint8_t[]) {
198                 0x04,  /*  u8  bLength */
199                 0x24,  /*  u8  bDescriptorType */
200                 UAS_PIPE_ID_DATA_OUT,
201                 0x00,  /*  u8  bReserved */
202             },
203         },
204     }
205 };
206 
207 static const USBDescDevice desc_device_high = {
208     .bcdUSB                        = 0x0200,
209     .bMaxPacketSize0               = 64,
210     .bNumConfigurations            = 1,
211     .confs = (USBDescConfig[]) {
212         {
213             .bNumInterfaces        = 1,
214             .bConfigurationValue   = 1,
215             .iConfiguration        = STR_CONFIG_HIGH,
216             .bmAttributes          = 0xc0,
217             .nif = 1,
218             .ifs = &desc_iface_high,
219         },
220     },
221 };
222 
223 static const USBDesc desc = {
224     .id = {
225         .idVendor          = 0x46f4, /* CRC16() of "QEMU" */
226         .idProduct         = 0x0003,
227         .bcdDevice         = 0,
228         .iManufacturer     = STR_MANUFACTURER,
229         .iProduct          = STR_PRODUCT,
230         .iSerialNumber     = STR_SERIALNUMBER,
231     },
232     .high = &desc_device_high,
233     .str  = desc_strings,
234 };
235 
236 /* --------------------------------------------------------------------- */
237 
238 static UASStatus *usb_uas_alloc_status(uint8_t id, uint16_t tag)
239 {
240     UASStatus *st = g_new0(UASStatus, 1);
241 
242     st->status.hdr.id = id;
243     st->status.hdr.tag = cpu_to_be16(tag);
244     st->length = sizeof(uas_ui_header);
245     return st;
246 }
247 
248 static void usb_uas_send_status_bh(void *opaque)
249 {
250     UASDevice *uas = opaque;
251     UASStatus *st = QTAILQ_FIRST(&uas->results);
252     USBPacket *p = uas->status;
253 
254     assert(p != NULL);
255     assert(st != NULL);
256 
257     uas->status = NULL;
258     usb_packet_copy(p, &st->status, st->length);
259     QTAILQ_REMOVE(&uas->results, st, next);
260     g_free(st);
261 
262     p->status = USB_RET_SUCCESS; /* Clear previous ASYNC status */
263     usb_packet_complete(&uas->dev, p);
264 }
265 
266 static void usb_uas_queue_status(UASDevice *uas, UASStatus *st, int length)
267 {
268     st->length += length;
269     QTAILQ_INSERT_TAIL(&uas->results, st, next);
270     if (uas->status) {
271         /*
272          * Just schedule bh make sure any in-flight data transaction
273          * is finished before completing (sending) the status packet.
274          */
275         qemu_bh_schedule(uas->status_bh);
276     } else {
277         USBEndpoint *ep = usb_ep_get(&uas->dev, USB_TOKEN_IN,
278                                      UAS_PIPE_ID_STATUS);
279         usb_wakeup(ep);
280     }
281 }
282 
283 static void usb_uas_queue_response(UASDevice *uas, uint16_t tag,
284                                    uint8_t code, uint16_t add_info)
285 {
286     UASStatus *st = usb_uas_alloc_status(UAS_UI_RESPONSE, tag);
287 
288     trace_usb_uas_response(uas->dev.addr, tag, code);
289     st->status.response.response_code = code;
290     st->status.response.add_response_info = cpu_to_be16(add_info);
291     usb_uas_queue_status(uas, st, sizeof(uas_ui_response));
292 }
293 
294 static void usb_uas_queue_sense(UASRequest *req, uint8_t status)
295 {
296     UASStatus *st = usb_uas_alloc_status(UAS_UI_SENSE, req->tag);
297     int len, slen = 0;
298 
299     trace_usb_uas_sense(req->uas->dev.addr, req->tag, status);
300     st->status.sense.status = status;
301     st->status.sense.status_qualifier = cpu_to_be16(0);
302     if (status != GOOD) {
303         slen = scsi_req_get_sense(req->req, st->status.sense.sense_data,
304                                   sizeof(st->status.sense.sense_data));
305         st->status.sense.sense_length = cpu_to_be16(slen);
306     }
307     len = sizeof(uas_ui_sense) - sizeof(st->status.sense.sense_data) + slen;
308     usb_uas_queue_status(req->uas, st, len);
309 }
310 
311 static void usb_uas_queue_read_ready(UASRequest *req)
312 {
313     UASStatus *st = usb_uas_alloc_status(UAS_UI_READ_READY, req->tag);
314 
315     trace_usb_uas_read_ready(req->uas->dev.addr, req->tag);
316     usb_uas_queue_status(req->uas, st, 0);
317 }
318 
319 static void usb_uas_queue_write_ready(UASRequest *req)
320 {
321     UASStatus *st = usb_uas_alloc_status(UAS_UI_WRITE_READY, req->tag);
322 
323     trace_usb_uas_write_ready(req->uas->dev.addr, req->tag);
324     usb_uas_queue_status(req->uas, st, 0);
325 }
326 
327 /* --------------------------------------------------------------------- */
328 
329 static int usb_uas_get_lun(uint64_t lun64)
330 {
331     return (lun64 >> 48) & 0xff;
332 }
333 
334 static SCSIDevice *usb_uas_get_dev(UASDevice *uas, uint64_t lun64)
335 {
336     if ((lun64 >> 56) != 0x00) {
337         return NULL;
338     }
339     return scsi_device_find(&uas->bus, 0, 0, usb_uas_get_lun(lun64));
340 }
341 
342 static void usb_uas_complete_data_packet(UASRequest *req)
343 {
344     USBPacket *p;
345 
346     if (!req->data_async) {
347         return;
348     }
349     p = req->data;
350     req->data = NULL;
351     req->data_async = false;
352     p->status = USB_RET_SUCCESS; /* Clear previous ASYNC status */
353     usb_packet_complete(&req->uas->dev, p);
354 }
355 
356 static void usb_uas_copy_data(UASRequest *req)
357 {
358     uint32_t length;
359 
360     length = MIN(req->buf_size - req->buf_off,
361                  req->data->iov.size - req->data->actual_length);
362     trace_usb_uas_xfer_data(req->uas->dev.addr, req->tag, length,
363                             req->data->actual_length, req->data->iov.size,
364                             req->buf_off, req->buf_size);
365     usb_packet_copy(req->data, scsi_req_get_buf(req->req) + req->buf_off,
366                     length);
367     req->buf_off += length;
368     req->data_off += length;
369 
370     if (req->data->actual_length == req->data->iov.size) {
371         usb_uas_complete_data_packet(req);
372     }
373     if (req->buf_size && req->buf_off == req->buf_size) {
374         req->buf_off = 0;
375         req->buf_size = 0;
376         scsi_req_continue(req->req);
377     }
378 }
379 
380 static void usb_uas_start_next_transfer(UASDevice *uas)
381 {
382     UASRequest *req;
383 
384     QTAILQ_FOREACH(req, &uas->requests, next) {
385         if (req->active || req->complete) {
386             continue;
387         }
388         if (req->req->cmd.mode == SCSI_XFER_FROM_DEV && uas->datain == NULL) {
389             uas->datain = req;
390             usb_uas_queue_read_ready(req);
391             req->active = true;
392             return;
393         }
394         if (req->req->cmd.mode == SCSI_XFER_TO_DEV && uas->dataout == NULL) {
395             uas->dataout = req;
396             usb_uas_queue_write_ready(req);
397             req->active = true;
398             return;
399         }
400     }
401 }
402 
403 static UASRequest *usb_uas_alloc_request(UASDevice *uas, uas_ui *ui)
404 {
405     UASRequest *req;
406 
407     req = g_new0(UASRequest, 1);
408     req->uas = uas;
409     req->tag = be16_to_cpu(ui->hdr.tag);
410     req->lun = be64_to_cpu(ui->command.lun);
411     req->dev = usb_uas_get_dev(req->uas, req->lun);
412     return req;
413 }
414 
415 static void usb_uas_scsi_free_request(SCSIBus *bus, void *priv)
416 {
417     UASRequest *req = priv;
418     UASDevice *uas = req->uas;
419 
420     if (req == uas->datain) {
421         uas->datain = NULL;
422     }
423     if (req == uas->dataout) {
424         uas->dataout = NULL;
425     }
426     QTAILQ_REMOVE(&uas->requests, req, next);
427     g_free(req);
428     usb_uas_start_next_transfer(uas);
429 }
430 
431 static UASRequest *usb_uas_find_request(UASDevice *uas, uint16_t tag)
432 {
433     UASRequest *req;
434 
435     QTAILQ_FOREACH(req, &uas->requests, next) {
436         if (req->tag == tag) {
437             return req;
438         }
439     }
440     return NULL;
441 }
442 
443 static void usb_uas_scsi_transfer_data(SCSIRequest *r, uint32_t len)
444 {
445     UASRequest *req = r->hba_private;
446 
447     trace_usb_uas_scsi_data(req->uas->dev.addr, req->tag, len);
448     req->buf_off = 0;
449     req->buf_size = len;
450     if (req->data) {
451         usb_uas_copy_data(req);
452     } else {
453         usb_uas_start_next_transfer(req->uas);
454     }
455 }
456 
457 static void usb_uas_scsi_command_complete(SCSIRequest *r,
458                                           uint32_t status, size_t resid)
459 {
460     UASRequest *req = r->hba_private;
461 
462     trace_usb_uas_scsi_complete(req->uas->dev.addr, req->tag, status, resid);
463     req->complete = true;
464     if (req->data) {
465         usb_uas_complete_data_packet(req);
466     }
467     usb_uas_queue_sense(req, status);
468     scsi_req_unref(req->req);
469 }
470 
471 static void usb_uas_scsi_request_cancelled(SCSIRequest *r)
472 {
473     UASRequest *req = r->hba_private;
474 
475     /* FIXME: queue notification to status pipe? */
476     scsi_req_unref(req->req);
477 }
478 
479 static const struct SCSIBusInfo usb_uas_scsi_info = {
480     .tcq = true,
481     .max_target = 0,
482     .max_lun = 255,
483 
484     .transfer_data = usb_uas_scsi_transfer_data,
485     .complete = usb_uas_scsi_command_complete,
486     .cancel = usb_uas_scsi_request_cancelled,
487     .free_request = usb_uas_scsi_free_request,
488 };
489 
490 /* --------------------------------------------------------------------- */
491 
492 static void usb_uas_handle_reset(USBDevice *dev)
493 {
494     UASDevice *uas = DO_UPCAST(UASDevice, dev, dev);
495     UASRequest *req, *nreq;
496     UASStatus *st, *nst;
497 
498     trace_usb_uas_reset(dev->addr);
499     QTAILQ_FOREACH_SAFE(req, &uas->requests, next, nreq) {
500         scsi_req_cancel(req->req);
501     }
502     QTAILQ_FOREACH_SAFE(st, &uas->results, next, nst) {
503         QTAILQ_REMOVE(&uas->results, st, next);
504         g_free(st);
505     }
506 }
507 
508 static void usb_uas_handle_control(USBDevice *dev, USBPacket *p,
509                int request, int value, int index, int length, uint8_t *data)
510 {
511     int ret;
512 
513     ret = usb_desc_handle_control(dev, p, request, value, index, length, data);
514     if (ret >= 0) {
515         return;
516     }
517     fprintf(stderr, "%s: unhandled control request\n", __func__);
518     p->status = USB_RET_STALL;
519 }
520 
521 static void usb_uas_cancel_io(USBDevice *dev, USBPacket *p)
522 {
523     UASDevice *uas = DO_UPCAST(UASDevice, dev, dev);
524     UASRequest *req, *nreq;
525 
526     if (uas->status == p) {
527         uas->status = NULL;
528         qemu_bh_cancel(uas->status_bh);
529         return;
530     }
531     QTAILQ_FOREACH_SAFE(req, &uas->requests, next, nreq) {
532         if (req->data == p) {
533             req->data = NULL;
534             return;
535         }
536     }
537     assert(!"canceled usb packet not found");
538 }
539 
540 static void usb_uas_command(UASDevice *uas, uas_ui *ui)
541 {
542     UASRequest *req;
543     uint32_t len;
544 
545     req = usb_uas_find_request(uas, be16_to_cpu(ui->hdr.tag));
546     if (req) {
547         goto overlapped_tag;
548     }
549     req = usb_uas_alloc_request(uas, ui);
550     if (req->dev == NULL) {
551         goto bad_target;
552     }
553 
554     trace_usb_uas_command(uas->dev.addr, req->tag,
555                           usb_uas_get_lun(req->lun),
556                           req->lun >> 32, req->lun & 0xffffffff);
557     QTAILQ_INSERT_TAIL(&uas->requests, req, next);
558     req->req = scsi_req_new(req->dev, req->tag,
559                             usb_uas_get_lun(req->lun),
560                             ui->command.cdb, req);
561     len = scsi_req_enqueue(req->req);
562     if (len) {
563         req->data_size = len;
564         scsi_req_continue(req->req);
565     }
566     return;
567 
568 overlapped_tag:
569     usb_uas_queue_response(uas, req->tag, UAS_RC_OVERLAPPED_TAG, 0);
570     return;
571 
572 bad_target:
573     /*
574      * FIXME: Seems to upset linux, is this wrong?
575      * NOTE: Happens only with no scsi devices at the bus, not sure
576      *       this is a valid UAS setup in the first place.
577      */
578     usb_uas_queue_response(uas, req->tag, UAS_RC_INVALID_INFO_UNIT, 0);
579     g_free(req);
580 }
581 
582 static void usb_uas_task(UASDevice *uas, uas_ui *ui)
583 {
584     uint16_t tag = be16_to_cpu(ui->hdr.tag);
585     uint64_t lun64 = be64_to_cpu(ui->task.lun);
586     SCSIDevice *dev = usb_uas_get_dev(uas, lun64);
587     int lun = usb_uas_get_lun(lun64);
588     UASRequest *req;
589     uint16_t task_tag;
590 
591     req = usb_uas_find_request(uas, be16_to_cpu(ui->hdr.tag));
592     if (req) {
593         goto overlapped_tag;
594     }
595 
596     switch (ui->task.function) {
597     case UAS_TMF_ABORT_TASK:
598         task_tag = be16_to_cpu(ui->task.task_tag);
599         trace_usb_uas_tmf_abort_task(uas->dev.addr, tag, task_tag);
600         if (dev == NULL) {
601             goto bad_target;
602         }
603         if (dev->lun != lun) {
604             goto incorrect_lun;
605         }
606         req = usb_uas_find_request(uas, task_tag);
607         if (req && req->dev == dev) {
608             scsi_req_cancel(req->req);
609         }
610         usb_uas_queue_response(uas, tag, UAS_RC_TMF_COMPLETE, 0);
611         break;
612 
613     case UAS_TMF_LOGICAL_UNIT_RESET:
614         trace_usb_uas_tmf_logical_unit_reset(uas->dev.addr, tag, lun);
615         if (dev == NULL) {
616             goto bad_target;
617         }
618         if (dev->lun != lun) {
619             goto incorrect_lun;
620         }
621         qdev_reset_all(&dev->qdev);
622         usb_uas_queue_response(uas, tag, UAS_RC_TMF_COMPLETE, 0);
623         break;
624 
625     default:
626         trace_usb_uas_tmf_unsupported(uas->dev.addr, tag, ui->task.function);
627         usb_uas_queue_response(uas, tag, UAS_RC_TMF_NOT_SUPPORTED, 0);
628         break;
629     }
630     return;
631 
632 overlapped_tag:
633     usb_uas_queue_response(uas, req->tag, UAS_RC_OVERLAPPED_TAG, 0);
634     return;
635 
636 bad_target:
637     /* FIXME: correct?  [see long comment in usb_uas_command()] */
638     usb_uas_queue_response(uas, tag, UAS_RC_INVALID_INFO_UNIT, 0);
639     return;
640 
641 incorrect_lun:
642     usb_uas_queue_response(uas, tag, UAS_RC_INCORRECT_LUN, 0);
643 }
644 
645 static void usb_uas_handle_data(USBDevice *dev, USBPacket *p)
646 {
647     UASDevice *uas = DO_UPCAST(UASDevice, dev, dev);
648     uas_ui ui;
649     UASStatus *st;
650     UASRequest *req;
651     int length;
652 
653     switch (p->ep->nr) {
654     case UAS_PIPE_ID_COMMAND:
655         length = MIN(sizeof(ui), p->iov.size);
656         usb_packet_copy(p, &ui, length);
657         switch (ui.hdr.id) {
658         case UAS_UI_COMMAND:
659             usb_uas_command(uas, &ui);
660             break;
661         case UAS_UI_TASK_MGMT:
662             usb_uas_task(uas, &ui);
663             break;
664         default:
665             fprintf(stderr, "%s: unknown command ui: id 0x%x\n",
666                     __func__, ui.hdr.id);
667             p->status = USB_RET_STALL;
668             break;
669         }
670         break;
671     case UAS_PIPE_ID_STATUS:
672         st = QTAILQ_FIRST(&uas->results);
673         if (st == NULL) {
674             assert(uas->status == NULL);
675             uas->status = p;
676             p->status = USB_RET_ASYNC;
677             break;
678         }
679         usb_packet_copy(p, &st->status, st->length);
680         QTAILQ_REMOVE(&uas->results, st, next);
681         g_free(st);
682         break;
683     case UAS_PIPE_ID_DATA_IN:
684     case UAS_PIPE_ID_DATA_OUT:
685         req = (p->ep->nr == UAS_PIPE_ID_DATA_IN) ? uas->datain : uas->dataout;
686         if (req == NULL) {
687             fprintf(stderr, "%s: no inflight request\n", __func__);
688             p->status = USB_RET_STALL;
689             break;
690         }
691         scsi_req_ref(req->req);
692         req->data = p;
693         usb_uas_copy_data(req);
694         if (p->actual_length == p->iov.size || req->complete) {
695             req->data = NULL;
696         } else {
697             req->data_async = true;
698             p->status = USB_RET_ASYNC;
699         }
700         scsi_req_unref(req->req);
701         usb_uas_start_next_transfer(uas);
702         break;
703     default:
704         fprintf(stderr, "%s: invalid endpoint %d\n", __func__, p->ep->nr);
705         p->status = USB_RET_STALL;
706         break;
707     }
708 }
709 
710 static void usb_uas_handle_destroy(USBDevice *dev)
711 {
712     UASDevice *uas = DO_UPCAST(UASDevice, dev, dev);
713 
714     qemu_bh_delete(uas->status_bh);
715 }
716 
717 static int usb_uas_init(USBDevice *dev)
718 {
719     UASDevice *uas = DO_UPCAST(UASDevice, dev, dev);
720 
721     usb_desc_create_serial(dev);
722     usb_desc_init(dev);
723 
724     QTAILQ_INIT(&uas->results);
725     QTAILQ_INIT(&uas->requests);
726     uas->status_bh = qemu_bh_new(usb_uas_send_status_bh, uas);
727 
728     scsi_bus_new(&uas->bus, &uas->dev.qdev, &usb_uas_scsi_info);
729 
730     return 0;
731 }
732 
733 static const VMStateDescription vmstate_usb_uas = {
734     .name = "usb-uas",
735     .unmigratable = 1,
736     .fields = (VMStateField[]) {
737         VMSTATE_USB_DEVICE(dev, UASDevice),
738         VMSTATE_END_OF_LIST()
739     }
740 };
741 
742 static void usb_uas_class_initfn(ObjectClass *klass, void *data)
743 {
744     DeviceClass *dc = DEVICE_CLASS(klass);
745     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
746 
747     uc->init           = usb_uas_init;
748     uc->product_desc   = desc_strings[STR_PRODUCT];
749     uc->usb_desc       = &desc;
750     uc->cancel_packet  = usb_uas_cancel_io;
751     uc->handle_attach  = usb_desc_attach;
752     uc->handle_reset   = usb_uas_handle_reset;
753     uc->handle_control = usb_uas_handle_control;
754     uc->handle_data    = usb_uas_handle_data;
755     uc->handle_destroy = usb_uas_handle_destroy;
756     dc->fw_name = "storage";
757     dc->vmsd = &vmstate_usb_uas;
758 }
759 
760 static const TypeInfo uas_info = {
761     .name          = "usb-uas",
762     .parent        = TYPE_USB_DEVICE,
763     .instance_size = sizeof(UASDevice),
764     .class_init    = usb_uas_class_initfn,
765 };
766 
767 static void usb_uas_register_types(void)
768 {
769     type_register_static(&uas_info);
770 }
771 
772 type_init(usb_uas_register_types)
773