xref: /qemu/hw/usb/dev-storage.c (revision d072cdf3)
1 /*
2  * USB Mass Storage Device emulation
3  *
4  * Copyright (c) 2006 CodeSourcery.
5  * Written by Paul Brook
6  *
7  * This code is licensed under the LGPL.
8  */
9 
10 #include "qemu-common.h"
11 #include "qemu/option.h"
12 #include "qemu/config-file.h"
13 #include "hw/usb.h"
14 #include "hw/usb/desc.h"
15 #include "hw/scsi/scsi.h"
16 #include "ui/console.h"
17 #include "monitor/monitor.h"
18 #include "sysemu/sysemu.h"
19 #include "sysemu/blockdev.h"
20 
21 //#define DEBUG_MSD
22 
23 #ifdef DEBUG_MSD
24 #define DPRINTF(fmt, ...) \
25 do { printf("usb-msd: " fmt , ## __VA_ARGS__); } while (0)
26 #else
27 #define DPRINTF(fmt, ...) do {} while(0)
28 #endif
29 
30 /* USB requests.  */
31 #define MassStorageReset  0xff
32 #define GetMaxLun         0xfe
33 
34 enum USBMSDMode {
35     USB_MSDM_CBW, /* Command Block.  */
36     USB_MSDM_DATAOUT, /* Transfer data to device.  */
37     USB_MSDM_DATAIN, /* Transfer data from device.  */
38     USB_MSDM_CSW /* Command Status.  */
39 };
40 
41 struct usb_msd_csw {
42     uint32_t sig;
43     uint32_t tag;
44     uint32_t residue;
45     uint8_t status;
46 };
47 
48 typedef struct {
49     USBDevice dev;
50     enum USBMSDMode mode;
51     uint32_t scsi_off;
52     uint32_t scsi_len;
53     uint32_t data_len;
54     struct usb_msd_csw csw;
55     SCSIRequest *req;
56     SCSIBus bus;
57     /* For async completion.  */
58     USBPacket *packet;
59     /* usb-storage only */
60     BlockConf conf;
61     uint32_t removable;
62 } MSDState;
63 
64 struct usb_msd_cbw {
65     uint32_t sig;
66     uint32_t tag;
67     uint32_t data_len;
68     uint8_t flags;
69     uint8_t lun;
70     uint8_t cmd_len;
71     uint8_t cmd[16];
72 };
73 
74 enum {
75     STR_MANUFACTURER = 1,
76     STR_PRODUCT,
77     STR_SERIALNUMBER,
78     STR_CONFIG_FULL,
79     STR_CONFIG_HIGH,
80     STR_CONFIG_SUPER,
81 };
82 
83 static const USBDescStrings desc_strings = {
84     [STR_MANUFACTURER] = "QEMU",
85     [STR_PRODUCT]      = "QEMU USB HARDDRIVE",
86     [STR_SERIALNUMBER] = "1",
87     [STR_CONFIG_FULL]  = "Full speed config (usb 1.1)",
88     [STR_CONFIG_HIGH]  = "High speed config (usb 2.0)",
89     [STR_CONFIG_SUPER] = "Super speed config (usb 3.0)",
90 };
91 
92 static const USBDescIface desc_iface_full = {
93     .bInterfaceNumber              = 0,
94     .bNumEndpoints                 = 2,
95     .bInterfaceClass               = USB_CLASS_MASS_STORAGE,
96     .bInterfaceSubClass            = 0x06, /* SCSI */
97     .bInterfaceProtocol            = 0x50, /* Bulk */
98     .eps = (USBDescEndpoint[]) {
99         {
100             .bEndpointAddress      = USB_DIR_IN | 0x01,
101             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
102             .wMaxPacketSize        = 64,
103         },{
104             .bEndpointAddress      = USB_DIR_OUT | 0x02,
105             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
106             .wMaxPacketSize        = 64,
107         },
108     }
109 };
110 
111 static const USBDescDevice desc_device_full = {
112     .bcdUSB                        = 0x0200,
113     .bMaxPacketSize0               = 8,
114     .bNumConfigurations            = 1,
115     .confs = (USBDescConfig[]) {
116         {
117             .bNumInterfaces        = 1,
118             .bConfigurationValue   = 1,
119             .iConfiguration        = STR_CONFIG_FULL,
120             .bmAttributes          = USB_CFG_ATT_ONE | USB_CFG_ATT_SELFPOWER,
121             .nif = 1,
122             .ifs = &desc_iface_full,
123         },
124     },
125 };
126 
127 static const USBDescIface desc_iface_high = {
128     .bInterfaceNumber              = 0,
129     .bNumEndpoints                 = 2,
130     .bInterfaceClass               = USB_CLASS_MASS_STORAGE,
131     .bInterfaceSubClass            = 0x06, /* SCSI */
132     .bInterfaceProtocol            = 0x50, /* Bulk */
133     .eps = (USBDescEndpoint[]) {
134         {
135             .bEndpointAddress      = USB_DIR_IN | 0x01,
136             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
137             .wMaxPacketSize        = 512,
138         },{
139             .bEndpointAddress      = USB_DIR_OUT | 0x02,
140             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
141             .wMaxPacketSize        = 512,
142         },
143     }
144 };
145 
146 static const USBDescDevice desc_device_high = {
147     .bcdUSB                        = 0x0200,
148     .bMaxPacketSize0               = 64,
149     .bNumConfigurations            = 1,
150     .confs = (USBDescConfig[]) {
151         {
152             .bNumInterfaces        = 1,
153             .bConfigurationValue   = 1,
154             .iConfiguration        = STR_CONFIG_HIGH,
155             .bmAttributes          = USB_CFG_ATT_ONE | USB_CFG_ATT_SELFPOWER,
156             .nif = 1,
157             .ifs = &desc_iface_high,
158         },
159     },
160 };
161 
162 static const USBDescIface desc_iface_super = {
163     .bInterfaceNumber              = 0,
164     .bNumEndpoints                 = 2,
165     .bInterfaceClass               = USB_CLASS_MASS_STORAGE,
166     .bInterfaceSubClass            = 0x06, /* SCSI */
167     .bInterfaceProtocol            = 0x50, /* Bulk */
168     .eps = (USBDescEndpoint[]) {
169         {
170             .bEndpointAddress      = USB_DIR_IN | 0x01,
171             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
172             .wMaxPacketSize        = 1024,
173             .bMaxBurst             = 15,
174         },{
175             .bEndpointAddress      = USB_DIR_OUT | 0x02,
176             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
177             .wMaxPacketSize        = 1024,
178             .bMaxBurst             = 15,
179         },
180     }
181 };
182 
183 static const USBDescDevice desc_device_super = {
184     .bcdUSB                        = 0x0300,
185     .bMaxPacketSize0               = 9,
186     .bNumConfigurations            = 1,
187     .confs = (USBDescConfig[]) {
188         {
189             .bNumInterfaces        = 1,
190             .bConfigurationValue   = 1,
191             .iConfiguration        = STR_CONFIG_SUPER,
192             .bmAttributes          = USB_CFG_ATT_ONE | USB_CFG_ATT_SELFPOWER,
193             .nif = 1,
194             .ifs = &desc_iface_super,
195         },
196     },
197 };
198 
199 static const USBDesc desc = {
200     .id = {
201         .idVendor          = 0x46f4, /* CRC16() of "QEMU" */
202         .idProduct         = 0x0001,
203         .bcdDevice         = 0,
204         .iManufacturer     = STR_MANUFACTURER,
205         .iProduct          = STR_PRODUCT,
206         .iSerialNumber     = STR_SERIALNUMBER,
207     },
208     .full  = &desc_device_full,
209     .high  = &desc_device_high,
210     .super = &desc_device_super,
211     .str   = desc_strings,
212 };
213 
214 static void usb_msd_copy_data(MSDState *s, USBPacket *p)
215 {
216     uint32_t len;
217     len = p->iov.size - p->actual_length;
218     if (len > s->scsi_len)
219         len = s->scsi_len;
220     usb_packet_copy(p, scsi_req_get_buf(s->req) + s->scsi_off, len);
221     s->scsi_len -= len;
222     s->scsi_off += len;
223     s->data_len -= len;
224     if (s->scsi_len == 0 || s->data_len == 0) {
225         scsi_req_continue(s->req);
226     }
227 }
228 
229 static void usb_msd_send_status(MSDState *s, USBPacket *p)
230 {
231     int len;
232 
233     DPRINTF("Command status %d tag 0x%x, len %zd\n",
234             s->csw.status, le32_to_cpu(s->csw.tag), p->iov.size);
235 
236     assert(s->csw.sig == cpu_to_le32(0x53425355));
237     len = MIN(sizeof(s->csw), p->iov.size);
238     usb_packet_copy(p, &s->csw, len);
239     memset(&s->csw, 0, sizeof(s->csw));
240 }
241 
242 static void usb_msd_packet_complete(MSDState *s)
243 {
244     USBPacket *p = s->packet;
245 
246     /* Set s->packet to NULL before calling usb_packet_complete
247        because another request may be issued before
248        usb_packet_complete returns.  */
249     DPRINTF("Packet complete %p\n", p);
250     s->packet = NULL;
251     usb_packet_complete(&s->dev, p);
252 }
253 
254 static void usb_msd_transfer_data(SCSIRequest *req, uint32_t len)
255 {
256     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
257     USBPacket *p = s->packet;
258 
259     assert((s->mode == USB_MSDM_DATAOUT) == (req->cmd.mode == SCSI_XFER_TO_DEV));
260     s->scsi_len = len;
261     s->scsi_off = 0;
262     if (p) {
263         usb_msd_copy_data(s, p);
264         p = s->packet;
265         if (p && p->actual_length == p->iov.size) {
266             p->status = USB_RET_SUCCESS; /* Clear previous ASYNC status */
267             usb_msd_packet_complete(s);
268         }
269     }
270 }
271 
272 static void usb_msd_command_complete(SCSIRequest *req, uint32_t status, size_t resid)
273 {
274     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
275     USBPacket *p = s->packet;
276 
277     DPRINTF("Command complete %d tag 0x%x\n", status, req->tag);
278 
279     s->csw.sig = cpu_to_le32(0x53425355);
280     s->csw.tag = cpu_to_le32(req->tag);
281     s->csw.residue = cpu_to_le32(s->data_len);
282     s->csw.status = status != 0;
283 
284     if (s->packet) {
285         if (s->data_len == 0 && s->mode == USB_MSDM_DATAOUT) {
286             /* A deferred packet with no write data remaining must be
287                the status read packet.  */
288             usb_msd_send_status(s, p);
289             s->mode = USB_MSDM_CBW;
290         } else if (s->mode == USB_MSDM_CSW) {
291             usb_msd_send_status(s, p);
292             s->mode = USB_MSDM_CBW;
293         } else {
294             if (s->data_len) {
295                 int len = (p->iov.size - p->actual_length);
296                 usb_packet_skip(p, len);
297                 s->data_len -= len;
298             }
299             if (s->data_len == 0) {
300                 s->mode = USB_MSDM_CSW;
301             }
302         }
303         p->status = USB_RET_SUCCESS; /* Clear previous ASYNC status */
304         usb_msd_packet_complete(s);
305     } else if (s->data_len == 0) {
306         s->mode = USB_MSDM_CSW;
307     }
308     scsi_req_unref(req);
309     s->req = NULL;
310 }
311 
312 static void usb_msd_request_cancelled(SCSIRequest *req)
313 {
314     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
315 
316     if (req == s->req) {
317         scsi_req_unref(s->req);
318         s->req = NULL;
319         s->scsi_len = 0;
320     }
321 }
322 
323 static void usb_msd_handle_reset(USBDevice *dev)
324 {
325     MSDState *s = (MSDState *)dev;
326 
327     DPRINTF("Reset\n");
328     if (s->req) {
329         scsi_req_cancel(s->req);
330     }
331     assert(s->req == NULL);
332 
333     if (s->packet) {
334         s->packet->status = USB_RET_STALL;
335         usb_msd_packet_complete(s);
336     }
337 
338     s->mode = USB_MSDM_CBW;
339 }
340 
341 static void usb_msd_handle_control(USBDevice *dev, USBPacket *p,
342                int request, int value, int index, int length, uint8_t *data)
343 {
344     MSDState *s = (MSDState *)dev;
345     SCSIDevice *scsi_dev;
346     int ret, maxlun;
347 
348     ret = usb_desc_handle_control(dev, p, request, value, index, length, data);
349     if (ret >= 0) {
350         return;
351     }
352 
353     switch (request) {
354     case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
355         break;
356         /* Class specific requests.  */
357     case ClassInterfaceOutRequest | MassStorageReset:
358         /* Reset state ready for the next CBW.  */
359         s->mode = USB_MSDM_CBW;
360         break;
361     case ClassInterfaceRequest | GetMaxLun:
362         maxlun = 0;
363         for (;;) {
364             scsi_dev = scsi_device_find(&s->bus, 0, 0, maxlun+1);
365             if (scsi_dev == NULL) {
366                 break;
367             }
368             if (scsi_dev->lun != maxlun+1) {
369                 break;
370             }
371             maxlun++;
372         }
373         DPRINTF("MaxLun %d\n", maxlun);
374         data[0] = maxlun;
375         p->actual_length = 1;
376         break;
377     default:
378         p->status = USB_RET_STALL;
379         break;
380     }
381 }
382 
383 static void usb_msd_cancel_io(USBDevice *dev, USBPacket *p)
384 {
385     MSDState *s = DO_UPCAST(MSDState, dev, dev);
386 
387     assert(s->packet == p);
388     s->packet = NULL;
389 
390     if (s->req) {
391         scsi_req_cancel(s->req);
392     }
393 }
394 
395 static void usb_msd_handle_data(USBDevice *dev, USBPacket *p)
396 {
397     MSDState *s = (MSDState *)dev;
398     uint32_t tag;
399     struct usb_msd_cbw cbw;
400     uint8_t devep = p->ep->nr;
401     SCSIDevice *scsi_dev;
402     uint32_t len;
403 
404     switch (p->pid) {
405     case USB_TOKEN_OUT:
406         if (devep != 2)
407             goto fail;
408 
409         switch (s->mode) {
410         case USB_MSDM_CBW:
411             if (p->iov.size != 31) {
412                 fprintf(stderr, "usb-msd: Bad CBW size");
413                 goto fail;
414             }
415             usb_packet_copy(p, &cbw, 31);
416             if (le32_to_cpu(cbw.sig) != 0x43425355) {
417                 fprintf(stderr, "usb-msd: Bad signature %08x\n",
418                         le32_to_cpu(cbw.sig));
419                 goto fail;
420             }
421             DPRINTF("Command on LUN %d\n", cbw.lun);
422             scsi_dev = scsi_device_find(&s->bus, 0, 0, cbw.lun);
423             if (scsi_dev == NULL) {
424                 fprintf(stderr, "usb-msd: Bad LUN %d\n", cbw.lun);
425                 goto fail;
426             }
427             tag = le32_to_cpu(cbw.tag);
428             s->data_len = le32_to_cpu(cbw.data_len);
429             if (s->data_len == 0) {
430                 s->mode = USB_MSDM_CSW;
431             } else if (cbw.flags & 0x80) {
432                 s->mode = USB_MSDM_DATAIN;
433             } else {
434                 s->mode = USB_MSDM_DATAOUT;
435             }
436             DPRINTF("Command tag 0x%x flags %08x len %d data %d\n",
437                     tag, cbw.flags, cbw.cmd_len, s->data_len);
438             assert(le32_to_cpu(s->csw.residue) == 0);
439             s->scsi_len = 0;
440             s->req = scsi_req_new(scsi_dev, tag, cbw.lun, cbw.cmd, NULL);
441 #ifdef DEBUG_MSD
442             scsi_req_print(s->req);
443 #endif
444             len = scsi_req_enqueue(s->req);
445             if (len) {
446                 scsi_req_continue(s->req);
447             }
448             break;
449 
450         case USB_MSDM_DATAOUT:
451             DPRINTF("Data out %zd/%d\n", p->iov.size, s->data_len);
452             if (p->iov.size > s->data_len) {
453                 goto fail;
454             }
455 
456             if (s->scsi_len) {
457                 usb_msd_copy_data(s, p);
458             }
459             if (le32_to_cpu(s->csw.residue)) {
460                 int len = p->iov.size - p->actual_length;
461                 if (len) {
462                     usb_packet_skip(p, len);
463                     s->data_len -= len;
464                     if (s->data_len == 0) {
465                         s->mode = USB_MSDM_CSW;
466                     }
467                 }
468             }
469             if (p->actual_length < p->iov.size) {
470                 DPRINTF("Deferring packet %p [wait data-out]\n", p);
471                 s->packet = p;
472                 p->status = USB_RET_ASYNC;
473             }
474             break;
475 
476         default:
477             DPRINTF("Unexpected write (len %zd)\n", p->iov.size);
478             goto fail;
479         }
480         break;
481 
482     case USB_TOKEN_IN:
483         if (devep != 1)
484             goto fail;
485 
486         switch (s->mode) {
487         case USB_MSDM_DATAOUT:
488             if (s->data_len != 0 || p->iov.size < 13) {
489                 goto fail;
490             }
491             /* Waiting for SCSI write to complete.  */
492             s->packet = p;
493             p->status = USB_RET_ASYNC;
494             break;
495 
496         case USB_MSDM_CSW:
497             if (p->iov.size < 13) {
498                 goto fail;
499             }
500 
501             if (s->req) {
502                 /* still in flight */
503                 DPRINTF("Deferring packet %p [wait status]\n", p);
504                 s->packet = p;
505                 p->status = USB_RET_ASYNC;
506             } else {
507                 usb_msd_send_status(s, p);
508                 s->mode = USB_MSDM_CBW;
509             }
510             break;
511 
512         case USB_MSDM_DATAIN:
513             DPRINTF("Data in %zd/%d, scsi_len %d\n",
514                     p->iov.size, s->data_len, s->scsi_len);
515             if (s->scsi_len) {
516                 usb_msd_copy_data(s, p);
517             }
518             if (le32_to_cpu(s->csw.residue)) {
519                 int len = p->iov.size - p->actual_length;
520                 if (len) {
521                     usb_packet_skip(p, len);
522                     s->data_len -= len;
523                     if (s->data_len == 0) {
524                         s->mode = USB_MSDM_CSW;
525                     }
526                 }
527             }
528             if (p->actual_length < p->iov.size) {
529                 DPRINTF("Deferring packet %p [wait data-in]\n", p);
530                 s->packet = p;
531                 p->status = USB_RET_ASYNC;
532             }
533             break;
534 
535         default:
536             DPRINTF("Unexpected read (len %zd)\n", p->iov.size);
537             goto fail;
538         }
539         break;
540 
541     default:
542         DPRINTF("Bad token\n");
543     fail:
544         p->status = USB_RET_STALL;
545         break;
546     }
547 }
548 
549 static void usb_msd_password_cb(void *opaque, int err)
550 {
551     MSDState *s = opaque;
552 
553     if (!err)
554         err = usb_device_attach(&s->dev);
555 
556     if (err)
557         qdev_unplug(&s->dev.qdev, NULL);
558 }
559 
560 static void *usb_msd_load_request(QEMUFile *f, SCSIRequest *req)
561 {
562     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
563 
564     /* nothing to load, just store req in our state struct */
565     assert(s->req == NULL);
566     scsi_req_ref(req);
567     s->req = req;
568     return NULL;
569 }
570 
571 static const struct SCSIBusInfo usb_msd_scsi_info_storage = {
572     .tcq = false,
573     .max_target = 0,
574     .max_lun = 0,
575 
576     .transfer_data = usb_msd_transfer_data,
577     .complete = usb_msd_command_complete,
578     .cancel = usb_msd_request_cancelled,
579     .load_request = usb_msd_load_request,
580 };
581 
582 static const struct SCSIBusInfo usb_msd_scsi_info_bot = {
583     .tcq = false,
584     .max_target = 0,
585     .max_lun = 15,
586 
587     .transfer_data = usb_msd_transfer_data,
588     .complete = usb_msd_command_complete,
589     .cancel = usb_msd_request_cancelled,
590     .load_request = usb_msd_load_request,
591 };
592 
593 static int usb_msd_initfn_storage(USBDevice *dev)
594 {
595     MSDState *s = DO_UPCAST(MSDState, dev, dev);
596     BlockDriverState *bs = s->conf.bs;
597     SCSIDevice *scsi_dev;
598     Error *err = NULL;
599 
600     if (!bs) {
601         error_report("drive property not set");
602         return -1;
603     }
604 
605     blkconf_serial(&s->conf, &dev->serial);
606 
607     /*
608      * Hack alert: this pretends to be a block device, but it's really
609      * a SCSI bus that can serve only a single device, which it
610      * creates automatically.  But first it needs to detach from its
611      * blockdev, or else scsi_bus_legacy_add_drive() dies when it
612      * attaches again.
613      *
614      * The hack is probably a bad idea.
615      */
616     bdrv_detach_dev(bs, &s->dev.qdev);
617     s->conf.bs = NULL;
618 
619     usb_desc_create_serial(dev);
620     usb_desc_init(dev);
621     scsi_bus_new(&s->bus, sizeof(s->bus), DEVICE(dev),
622                  &usb_msd_scsi_info_storage, NULL);
623     scsi_dev = scsi_bus_legacy_add_drive(&s->bus, bs, 0, !!s->removable,
624                                          s->conf.bootindex, dev->serial,
625                                          &err);
626     if (!scsi_dev) {
627         return -1;
628     }
629     s->bus.qbus.allow_hotplug = 0;
630     usb_msd_handle_reset(dev);
631 
632     if (bdrv_key_required(bs)) {
633         if (cur_mon) {
634             monitor_read_bdrv_key_start(cur_mon, bs, usb_msd_password_cb, s);
635             s->dev.auto_attach = 0;
636         } else {
637             autostart = 0;
638         }
639     }
640 
641     return 0;
642 }
643 
644 static int usb_msd_initfn_bot(USBDevice *dev)
645 {
646     MSDState *s = DO_UPCAST(MSDState, dev, dev);
647 
648     usb_desc_create_serial(dev);
649     usb_desc_init(dev);
650     scsi_bus_new(&s->bus, sizeof(s->bus), DEVICE(dev),
651                  &usb_msd_scsi_info_bot, NULL);
652     s->bus.qbus.allow_hotplug = 0;
653     usb_msd_handle_reset(dev);
654 
655     return 0;
656 }
657 
658 static USBDevice *usb_msd_init(USBBus *bus, const char *filename)
659 {
660     static int nr=0;
661     char id[8];
662     QemuOpts *opts;
663     DriveInfo *dinfo;
664     USBDevice *dev;
665     const char *p1;
666     char fmt[32];
667 
668     /* parse -usbdevice disk: syntax into drive opts */
669     snprintf(id, sizeof(id), "usb%d", nr++);
670     opts = qemu_opts_create(qemu_find_opts("drive"), id, 0, NULL);
671 
672     p1 = strchr(filename, ':');
673     if (p1++) {
674         const char *p2;
675 
676         if (strstart(filename, "format=", &p2)) {
677             int len = MIN(p1 - p2, sizeof(fmt));
678             pstrcpy(fmt, len, p2);
679             qemu_opt_set(opts, "format", fmt);
680         } else if (*filename != ':') {
681             printf("unrecognized USB mass-storage option %s\n", filename);
682             return NULL;
683         }
684         filename = p1;
685     }
686     if (!*filename) {
687         printf("block device specification needed\n");
688         return NULL;
689     }
690     qemu_opt_set(opts, "file", filename);
691     qemu_opt_set(opts, "if", "none");
692 
693     /* create host drive */
694     dinfo = drive_new(opts, 0);
695     if (!dinfo) {
696         qemu_opts_del(opts);
697         return NULL;
698     }
699 
700     /* create guest device */
701     dev = usb_create(bus, "usb-storage");
702     if (!dev) {
703         return NULL;
704     }
705     if (qdev_prop_set_drive(&dev->qdev, "drive", dinfo->bdrv) < 0) {
706         object_unparent(OBJECT(dev));
707         return NULL;
708     }
709     if (qdev_init(&dev->qdev) < 0)
710         return NULL;
711 
712     return dev;
713 }
714 
715 static const VMStateDescription vmstate_usb_msd = {
716     .name = "usb-storage",
717     .version_id = 1,
718     .minimum_version_id = 1,
719     .fields = (VMStateField[]) {
720         VMSTATE_USB_DEVICE(dev, MSDState),
721         VMSTATE_UINT32(mode, MSDState),
722         VMSTATE_UINT32(scsi_len, MSDState),
723         VMSTATE_UINT32(scsi_off, MSDState),
724         VMSTATE_UINT32(data_len, MSDState),
725         VMSTATE_UINT32(csw.sig, MSDState),
726         VMSTATE_UINT32(csw.tag, MSDState),
727         VMSTATE_UINT32(csw.residue, MSDState),
728         VMSTATE_UINT8(csw.status, MSDState),
729         VMSTATE_END_OF_LIST()
730     }
731 };
732 
733 static Property msd_properties[] = {
734     DEFINE_BLOCK_PROPERTIES(MSDState, conf),
735     DEFINE_PROP_BIT("removable", MSDState, removable, 0, false),
736     DEFINE_PROP_END_OF_LIST(),
737 };
738 
739 static void usb_msd_class_initfn_common(ObjectClass *klass)
740 {
741     DeviceClass *dc = DEVICE_CLASS(klass);
742     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
743 
744     uc->product_desc   = "QEMU USB MSD";
745     uc->usb_desc       = &desc;
746     uc->cancel_packet  = usb_msd_cancel_io;
747     uc->handle_attach  = usb_desc_attach;
748     uc->handle_reset   = usb_msd_handle_reset;
749     uc->handle_control = usb_msd_handle_control;
750     uc->handle_data    = usb_msd_handle_data;
751     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
752     dc->fw_name = "storage";
753     dc->vmsd = &vmstate_usb_msd;
754 }
755 
756 static void usb_msd_class_initfn_storage(ObjectClass *klass, void *data)
757 {
758     DeviceClass *dc = DEVICE_CLASS(klass);
759     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
760 
761     uc->init = usb_msd_initfn_storage;
762     dc->props = msd_properties;
763     usb_msd_class_initfn_common(klass);
764 }
765 
766 static void usb_msd_class_initfn_bot(ObjectClass *klass, void *data)
767 {
768     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
769 
770     uc->init = usb_msd_initfn_bot;
771     usb_msd_class_initfn_common(klass);
772 }
773 
774 static const TypeInfo msd_info = {
775     .name          = "usb-storage",
776     .parent        = TYPE_USB_DEVICE,
777     .instance_size = sizeof(MSDState),
778     .class_init    = usb_msd_class_initfn_storage,
779 };
780 
781 static const TypeInfo bot_info = {
782     .name          = "usb-bot",
783     .parent        = TYPE_USB_DEVICE,
784     .instance_size = sizeof(MSDState),
785     .class_init    = usb_msd_class_initfn_bot,
786 };
787 
788 static void usb_msd_register_types(void)
789 {
790     type_register_static(&msd_info);
791     type_register_static(&bot_info);
792     usb_legacy_register("usb-storage", "disk", usb_msd_init);
793 }
794 
795 type_init(usb_msd_register_types)
796