xref: /openbmc/qemu/hw/usb/dev-storage.c (revision d84be02d)
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/osdep.h"
11 #include "qapi/error.h"
12 #include "qemu-common.h"
13 #include "qemu/error-report.h"
14 #include "qemu/option.h"
15 #include "qemu/config-file.h"
16 #include "hw/usb.h"
17 #include "hw/usb/desc.h"
18 #include "hw/scsi/scsi.h"
19 #include "ui/console.h"
20 #include "monitor/monitor.h"
21 #include "sysemu/sysemu.h"
22 #include "sysemu/block-backend.h"
23 #include "sysemu/blockdev.h"
24 #include "qapi/visitor.h"
25 #include "qemu/cutils.h"
26 
27 //#define DEBUG_MSD
28 
29 #ifdef DEBUG_MSD
30 #define DPRINTF(fmt, ...) \
31 do { printf("usb-msd: " fmt , ## __VA_ARGS__); } while (0)
32 #else
33 #define DPRINTF(fmt, ...) do {} while(0)
34 #endif
35 
36 /* USB requests.  */
37 #define MassStorageReset  0xff
38 #define GetMaxLun         0xfe
39 
40 enum USBMSDMode {
41     USB_MSDM_CBW, /* Command Block.  */
42     USB_MSDM_DATAOUT, /* Transfer data to device.  */
43     USB_MSDM_DATAIN, /* Transfer data from device.  */
44     USB_MSDM_CSW /* Command Status.  */
45 };
46 
47 struct usb_msd_csw {
48     uint32_t sig;
49     uint32_t tag;
50     uint32_t residue;
51     uint8_t status;
52 };
53 
54 typedef struct {
55     USBDevice dev;
56     enum USBMSDMode mode;
57     uint32_t scsi_off;
58     uint32_t scsi_len;
59     uint32_t data_len;
60     struct usb_msd_csw csw;
61     SCSIRequest *req;
62     SCSIBus bus;
63     /* For async completion.  */
64     USBPacket *packet;
65     /* usb-storage only */
66     BlockConf conf;
67     uint32_t removable;
68     SCSIDevice *scsi_dev;
69 } MSDState;
70 
71 #define TYPE_USB_STORAGE "usb-storage-dev"
72 #define USB_STORAGE_DEV(obj) OBJECT_CHECK(MSDState, (obj), TYPE_USB_STORAGE)
73 
74 struct usb_msd_cbw {
75     uint32_t sig;
76     uint32_t tag;
77     uint32_t data_len;
78     uint8_t flags;
79     uint8_t lun;
80     uint8_t cmd_len;
81     uint8_t cmd[16];
82 };
83 
84 enum {
85     STR_MANUFACTURER = 1,
86     STR_PRODUCT,
87     STR_SERIALNUMBER,
88     STR_CONFIG_FULL,
89     STR_CONFIG_HIGH,
90     STR_CONFIG_SUPER,
91 };
92 
93 static const USBDescStrings desc_strings = {
94     [STR_MANUFACTURER] = "QEMU",
95     [STR_PRODUCT]      = "QEMU USB HARDDRIVE",
96     [STR_SERIALNUMBER] = "1",
97     [STR_CONFIG_FULL]  = "Full speed config (usb 1.1)",
98     [STR_CONFIG_HIGH]  = "High speed config (usb 2.0)",
99     [STR_CONFIG_SUPER] = "Super speed config (usb 3.0)",
100 };
101 
102 static const USBDescIface desc_iface_full = {
103     .bInterfaceNumber              = 0,
104     .bNumEndpoints                 = 2,
105     .bInterfaceClass               = USB_CLASS_MASS_STORAGE,
106     .bInterfaceSubClass            = 0x06, /* SCSI */
107     .bInterfaceProtocol            = 0x50, /* Bulk */
108     .eps = (USBDescEndpoint[]) {
109         {
110             .bEndpointAddress      = USB_DIR_IN | 0x01,
111             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
112             .wMaxPacketSize        = 64,
113         },{
114             .bEndpointAddress      = USB_DIR_OUT | 0x02,
115             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
116             .wMaxPacketSize        = 64,
117         },
118     }
119 };
120 
121 static const USBDescDevice desc_device_full = {
122     .bcdUSB                        = 0x0200,
123     .bMaxPacketSize0               = 8,
124     .bNumConfigurations            = 1,
125     .confs = (USBDescConfig[]) {
126         {
127             .bNumInterfaces        = 1,
128             .bConfigurationValue   = 1,
129             .iConfiguration        = STR_CONFIG_FULL,
130             .bmAttributes          = USB_CFG_ATT_ONE | USB_CFG_ATT_SELFPOWER,
131             .nif = 1,
132             .ifs = &desc_iface_full,
133         },
134     },
135 };
136 
137 static const USBDescIface desc_iface_high = {
138     .bInterfaceNumber              = 0,
139     .bNumEndpoints                 = 2,
140     .bInterfaceClass               = USB_CLASS_MASS_STORAGE,
141     .bInterfaceSubClass            = 0x06, /* SCSI */
142     .bInterfaceProtocol            = 0x50, /* Bulk */
143     .eps = (USBDescEndpoint[]) {
144         {
145             .bEndpointAddress      = USB_DIR_IN | 0x01,
146             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
147             .wMaxPacketSize        = 512,
148         },{
149             .bEndpointAddress      = USB_DIR_OUT | 0x02,
150             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
151             .wMaxPacketSize        = 512,
152         },
153     }
154 };
155 
156 static const USBDescDevice desc_device_high = {
157     .bcdUSB                        = 0x0200,
158     .bMaxPacketSize0               = 64,
159     .bNumConfigurations            = 1,
160     .confs = (USBDescConfig[]) {
161         {
162             .bNumInterfaces        = 1,
163             .bConfigurationValue   = 1,
164             .iConfiguration        = STR_CONFIG_HIGH,
165             .bmAttributes          = USB_CFG_ATT_ONE | USB_CFG_ATT_SELFPOWER,
166             .nif = 1,
167             .ifs = &desc_iface_high,
168         },
169     },
170 };
171 
172 static const USBDescIface desc_iface_super = {
173     .bInterfaceNumber              = 0,
174     .bNumEndpoints                 = 2,
175     .bInterfaceClass               = USB_CLASS_MASS_STORAGE,
176     .bInterfaceSubClass            = 0x06, /* SCSI */
177     .bInterfaceProtocol            = 0x50, /* Bulk */
178     .eps = (USBDescEndpoint[]) {
179         {
180             .bEndpointAddress      = USB_DIR_IN | 0x01,
181             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
182             .wMaxPacketSize        = 1024,
183             .bMaxBurst             = 15,
184         },{
185             .bEndpointAddress      = USB_DIR_OUT | 0x02,
186             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
187             .wMaxPacketSize        = 1024,
188             .bMaxBurst             = 15,
189         },
190     }
191 };
192 
193 static const USBDescDevice desc_device_super = {
194     .bcdUSB                        = 0x0300,
195     .bMaxPacketSize0               = 9,
196     .bNumConfigurations            = 1,
197     .confs = (USBDescConfig[]) {
198         {
199             .bNumInterfaces        = 1,
200             .bConfigurationValue   = 1,
201             .iConfiguration        = STR_CONFIG_SUPER,
202             .bmAttributes          = USB_CFG_ATT_ONE | USB_CFG_ATT_SELFPOWER,
203             .nif = 1,
204             .ifs = &desc_iface_super,
205         },
206     },
207 };
208 
209 static const USBDesc desc = {
210     .id = {
211         .idVendor          = 0x46f4, /* CRC16() of "QEMU" */
212         .idProduct         = 0x0001,
213         .bcdDevice         = 0,
214         .iManufacturer     = STR_MANUFACTURER,
215         .iProduct          = STR_PRODUCT,
216         .iSerialNumber     = STR_SERIALNUMBER,
217     },
218     .full  = &desc_device_full,
219     .high  = &desc_device_high,
220     .super = &desc_device_super,
221     .str   = desc_strings,
222 };
223 
224 static void usb_msd_copy_data(MSDState *s, USBPacket *p)
225 {
226     uint32_t len;
227     len = p->iov.size - p->actual_length;
228     if (len > s->scsi_len)
229         len = s->scsi_len;
230     usb_packet_copy(p, scsi_req_get_buf(s->req) + s->scsi_off, len);
231     s->scsi_len -= len;
232     s->scsi_off += len;
233     s->data_len -= len;
234     if (s->scsi_len == 0 || s->data_len == 0) {
235         scsi_req_continue(s->req);
236     }
237 }
238 
239 static void usb_msd_send_status(MSDState *s, USBPacket *p)
240 {
241     int len;
242 
243     DPRINTF("Command status %d tag 0x%x, len %zd\n",
244             s->csw.status, le32_to_cpu(s->csw.tag), p->iov.size);
245 
246     assert(s->csw.sig == cpu_to_le32(0x53425355));
247     len = MIN(sizeof(s->csw), p->iov.size);
248     usb_packet_copy(p, &s->csw, len);
249     memset(&s->csw, 0, sizeof(s->csw));
250 }
251 
252 static void usb_msd_packet_complete(MSDState *s)
253 {
254     USBPacket *p = s->packet;
255 
256     /* Set s->packet to NULL before calling usb_packet_complete
257        because another request may be issued before
258        usb_packet_complete returns.  */
259     DPRINTF("Packet complete %p\n", p);
260     s->packet = NULL;
261     usb_packet_complete(&s->dev, p);
262 }
263 
264 static void usb_msd_transfer_data(SCSIRequest *req, uint32_t len)
265 {
266     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
267     USBPacket *p = s->packet;
268 
269     assert((s->mode == USB_MSDM_DATAOUT) == (req->cmd.mode == SCSI_XFER_TO_DEV));
270     s->scsi_len = len;
271     s->scsi_off = 0;
272     if (p) {
273         usb_msd_copy_data(s, p);
274         p = s->packet;
275         if (p && p->actual_length == p->iov.size) {
276             p->status = USB_RET_SUCCESS; /* Clear previous ASYNC status */
277             usb_msd_packet_complete(s);
278         }
279     }
280 }
281 
282 static void usb_msd_command_complete(SCSIRequest *req, uint32_t status, size_t resid)
283 {
284     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
285     USBPacket *p = s->packet;
286 
287     DPRINTF("Command complete %d tag 0x%x\n", status, req->tag);
288 
289     s->csw.sig = cpu_to_le32(0x53425355);
290     s->csw.tag = cpu_to_le32(req->tag);
291     s->csw.residue = cpu_to_le32(s->data_len);
292     s->csw.status = status != 0;
293 
294     if (s->packet) {
295         if (s->data_len == 0 && s->mode == USB_MSDM_DATAOUT) {
296             /* A deferred packet with no write data remaining must be
297                the status read packet.  */
298             usb_msd_send_status(s, p);
299             s->mode = USB_MSDM_CBW;
300         } else if (s->mode == USB_MSDM_CSW) {
301             usb_msd_send_status(s, p);
302             s->mode = USB_MSDM_CBW;
303         } else {
304             if (s->data_len) {
305                 int len = (p->iov.size - p->actual_length);
306                 usb_packet_skip(p, len);
307                 s->data_len -= len;
308             }
309             if (s->data_len == 0) {
310                 s->mode = USB_MSDM_CSW;
311             }
312         }
313         p->status = USB_RET_SUCCESS; /* Clear previous ASYNC status */
314         usb_msd_packet_complete(s);
315     } else if (s->data_len == 0) {
316         s->mode = USB_MSDM_CSW;
317     }
318     scsi_req_unref(req);
319     s->req = NULL;
320 }
321 
322 static void usb_msd_request_cancelled(SCSIRequest *req)
323 {
324     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
325 
326     if (req == s->req) {
327         scsi_req_unref(s->req);
328         s->req = NULL;
329         s->scsi_len = 0;
330     }
331 }
332 
333 static void usb_msd_handle_reset(USBDevice *dev)
334 {
335     MSDState *s = (MSDState *)dev;
336 
337     DPRINTF("Reset\n");
338     if (s->req) {
339         scsi_req_cancel(s->req);
340     }
341     assert(s->req == NULL);
342 
343     if (s->packet) {
344         s->packet->status = USB_RET_STALL;
345         usb_msd_packet_complete(s);
346     }
347 
348     s->mode = USB_MSDM_CBW;
349 }
350 
351 static void usb_msd_handle_control(USBDevice *dev, USBPacket *p,
352                int request, int value, int index, int length, uint8_t *data)
353 {
354     MSDState *s = (MSDState *)dev;
355     SCSIDevice *scsi_dev;
356     int ret, maxlun;
357 
358     ret = usb_desc_handle_control(dev, p, request, value, index, length, data);
359     if (ret >= 0) {
360         return;
361     }
362 
363     switch (request) {
364     case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
365         break;
366         /* Class specific requests.  */
367     case ClassInterfaceOutRequest | MassStorageReset:
368         /* Reset state ready for the next CBW.  */
369         s->mode = USB_MSDM_CBW;
370         break;
371     case ClassInterfaceRequest | GetMaxLun:
372         maxlun = 0;
373         for (;;) {
374             scsi_dev = scsi_device_find(&s->bus, 0, 0, maxlun+1);
375             if (scsi_dev == NULL) {
376                 break;
377             }
378             if (scsi_dev->lun != maxlun+1) {
379                 break;
380             }
381             maxlun++;
382         }
383         DPRINTF("MaxLun %d\n", maxlun);
384         data[0] = maxlun;
385         p->actual_length = 1;
386         break;
387     default:
388         p->status = USB_RET_STALL;
389         break;
390     }
391 }
392 
393 static void usb_msd_cancel_io(USBDevice *dev, USBPacket *p)
394 {
395     MSDState *s = USB_STORAGE_DEV(dev);
396 
397     assert(s->packet == p);
398     s->packet = NULL;
399 
400     if (s->req) {
401         scsi_req_cancel(s->req);
402     }
403 }
404 
405 static void usb_msd_handle_data(USBDevice *dev, USBPacket *p)
406 {
407     MSDState *s = (MSDState *)dev;
408     uint32_t tag;
409     struct usb_msd_cbw cbw;
410     uint8_t devep = p->ep->nr;
411     SCSIDevice *scsi_dev;
412     uint32_t len;
413 
414     switch (p->pid) {
415     case USB_TOKEN_OUT:
416         if (devep != 2)
417             goto fail;
418 
419         switch (s->mode) {
420         case USB_MSDM_CBW:
421             if (p->iov.size != 31) {
422                 error_report("usb-msd: Bad CBW size");
423                 goto fail;
424             }
425             usb_packet_copy(p, &cbw, 31);
426             if (le32_to_cpu(cbw.sig) != 0x43425355) {
427                 error_report("usb-msd: Bad signature %08x",
428                              le32_to_cpu(cbw.sig));
429                 goto fail;
430             }
431             DPRINTF("Command on LUN %d\n", cbw.lun);
432             scsi_dev = scsi_device_find(&s->bus, 0, 0, cbw.lun);
433             if (scsi_dev == NULL) {
434                 error_report("usb-msd: Bad LUN %d", cbw.lun);
435                 goto fail;
436             }
437             tag = le32_to_cpu(cbw.tag);
438             s->data_len = le32_to_cpu(cbw.data_len);
439             if (s->data_len == 0) {
440                 s->mode = USB_MSDM_CSW;
441             } else if (cbw.flags & 0x80) {
442                 s->mode = USB_MSDM_DATAIN;
443             } else {
444                 s->mode = USB_MSDM_DATAOUT;
445             }
446             DPRINTF("Command tag 0x%x flags %08x len %d data %d\n",
447                     tag, cbw.flags, cbw.cmd_len, s->data_len);
448             assert(le32_to_cpu(s->csw.residue) == 0);
449             s->scsi_len = 0;
450             s->req = scsi_req_new(scsi_dev, tag, cbw.lun, cbw.cmd, NULL);
451 #ifdef DEBUG_MSD
452             scsi_req_print(s->req);
453 #endif
454             len = scsi_req_enqueue(s->req);
455             if (len) {
456                 scsi_req_continue(s->req);
457             }
458             break;
459 
460         case USB_MSDM_DATAOUT:
461             DPRINTF("Data out %zd/%d\n", p->iov.size, s->data_len);
462             if (p->iov.size > s->data_len) {
463                 goto fail;
464             }
465 
466             if (s->scsi_len) {
467                 usb_msd_copy_data(s, p);
468             }
469             if (le32_to_cpu(s->csw.residue)) {
470                 int len = p->iov.size - p->actual_length;
471                 if (len) {
472                     usb_packet_skip(p, len);
473                     s->data_len -= len;
474                     if (s->data_len == 0) {
475                         s->mode = USB_MSDM_CSW;
476                     }
477                 }
478             }
479             if (p->actual_length < p->iov.size) {
480                 DPRINTF("Deferring packet %p [wait data-out]\n", p);
481                 s->packet = p;
482                 p->status = USB_RET_ASYNC;
483             }
484             break;
485 
486         default:
487             DPRINTF("Unexpected write (len %zd)\n", p->iov.size);
488             goto fail;
489         }
490         break;
491 
492     case USB_TOKEN_IN:
493         if (devep != 1)
494             goto fail;
495 
496         switch (s->mode) {
497         case USB_MSDM_DATAOUT:
498             if (s->data_len != 0 || p->iov.size < 13) {
499                 goto fail;
500             }
501             /* Waiting for SCSI write to complete.  */
502             s->packet = p;
503             p->status = USB_RET_ASYNC;
504             break;
505 
506         case USB_MSDM_CSW:
507             if (p->iov.size < 13) {
508                 goto fail;
509             }
510 
511             if (s->req) {
512                 /* still in flight */
513                 DPRINTF("Deferring packet %p [wait status]\n", p);
514                 s->packet = p;
515                 p->status = USB_RET_ASYNC;
516             } else {
517                 usb_msd_send_status(s, p);
518                 s->mode = USB_MSDM_CBW;
519             }
520             break;
521 
522         case USB_MSDM_DATAIN:
523             DPRINTF("Data in %zd/%d, scsi_len %d\n",
524                     p->iov.size, s->data_len, s->scsi_len);
525             if (s->scsi_len) {
526                 usb_msd_copy_data(s, p);
527             }
528             if (le32_to_cpu(s->csw.residue)) {
529                 int len = p->iov.size - p->actual_length;
530                 if (len) {
531                     usb_packet_skip(p, len);
532                     s->data_len -= len;
533                     if (s->data_len == 0) {
534                         s->mode = USB_MSDM_CSW;
535                     }
536                 }
537             }
538             if (p->actual_length < p->iov.size) {
539                 DPRINTF("Deferring packet %p [wait data-in]\n", p);
540                 s->packet = p;
541                 p->status = USB_RET_ASYNC;
542             }
543             break;
544 
545         default:
546             DPRINTF("Unexpected read (len %zd)\n", p->iov.size);
547             goto fail;
548         }
549         break;
550 
551     default:
552         DPRINTF("Bad token\n");
553     fail:
554         p->status = USB_RET_STALL;
555         break;
556     }
557 }
558 
559 static void *usb_msd_load_request(QEMUFile *f, SCSIRequest *req)
560 {
561     MSDState *s = DO_UPCAST(MSDState, dev.qdev, req->bus->qbus.parent);
562 
563     /* nothing to load, just store req in our state struct */
564     assert(s->req == NULL);
565     scsi_req_ref(req);
566     s->req = req;
567     return NULL;
568 }
569 
570 static const struct SCSIBusInfo usb_msd_scsi_info_storage = {
571     .tcq = false,
572     .max_target = 0,
573     .max_lun = 0,
574 
575     .transfer_data = usb_msd_transfer_data,
576     .complete = usb_msd_command_complete,
577     .cancel = usb_msd_request_cancelled,
578     .load_request = usb_msd_load_request,
579 };
580 
581 static const struct SCSIBusInfo usb_msd_scsi_info_bot = {
582     .tcq = false,
583     .max_target = 0,
584     .max_lun = 15,
585 
586     .transfer_data = usb_msd_transfer_data,
587     .complete = usb_msd_command_complete,
588     .cancel = usb_msd_request_cancelled,
589     .load_request = usb_msd_load_request,
590 };
591 
592 static void usb_msd_unrealize_storage(USBDevice *dev, Error **errp)
593 {
594     MSDState *s = USB_STORAGE_DEV(dev);
595 
596     object_unref(OBJECT(&s->bus));
597 }
598 
599 static void usb_msd_storage_realize(USBDevice *dev, Error **errp)
600 {
601     MSDState *s = USB_STORAGE_DEV(dev);
602     BlockBackend *blk = s->conf.blk;
603     SCSIDevice *scsi_dev;
604 
605     if (!blk) {
606         error_setg(errp, "drive property not set");
607         return;
608     }
609 
610     blkconf_serial(&s->conf, &dev->serial);
611     blkconf_blocksizes(&s->conf);
612     if (!blkconf_apply_backend_options(&s->conf, blk_is_read_only(blk), true,
613                                        errp)) {
614         return;
615     }
616 
617     /*
618      * Hack alert: this pretends to be a block device, but it's really
619      * a SCSI bus that can serve only a single device, which it
620      * creates automatically.  But first it needs to detach from its
621      * blockdev, or else scsi_bus_legacy_add_drive() dies when it
622      * attaches again. We also need to take another reference so that
623      * blk_detach_dev() doesn't free blk while we still need it.
624      *
625      * The hack is probably a bad idea.
626      */
627     blk_ref(blk);
628     blk_detach_dev(blk, &s->dev.qdev);
629     s->conf.blk = NULL;
630 
631     usb_desc_create_serial(dev);
632     usb_desc_init(dev);
633     scsi_bus_new(&s->bus, sizeof(s->bus), DEVICE(dev),
634                  &usb_msd_scsi_info_storage, NULL);
635     scsi_dev = scsi_bus_legacy_add_drive(&s->bus, blk, 0, !!s->removable,
636                                          s->conf.bootindex, dev->serial,
637                                          errp);
638     blk_unref(blk);
639     if (!scsi_dev) {
640         return;
641     }
642     usb_msd_handle_reset(dev);
643     s->scsi_dev = scsi_dev;
644 }
645 
646 static void usb_msd_bot_unrealize(USBDevice *dev, Error **errp)
647 {
648     MSDState *s = USB_STORAGE_DEV(dev);
649 
650     object_unref(OBJECT(&s->bus));
651 }
652 
653 static void usb_msd_bot_realize(USBDevice *dev, Error **errp)
654 {
655     MSDState *s = USB_STORAGE_DEV(dev);
656     DeviceState *d = DEVICE(dev);
657 
658     usb_desc_create_serial(dev);
659     usb_desc_init(dev);
660     if (d->hotplugged) {
661         s->dev.auto_attach = 0;
662     }
663 
664     scsi_bus_new(&s->bus, sizeof(s->bus), DEVICE(dev),
665                  &usb_msd_scsi_info_bot, NULL);
666     usb_msd_handle_reset(dev);
667 }
668 
669 static USBDevice *usb_msd_init(USBBus *bus, const char *filename)
670 {
671     static int nr=0;
672     Error *err = NULL;
673     char id[8];
674     QemuOpts *opts;
675     DriveInfo *dinfo;
676     USBDevice *dev;
677     const char *p1;
678     char fmt[32];
679 
680     /* parse -usbdevice disk: syntax into drive opts */
681     do {
682         snprintf(id, sizeof(id), "usb%d", nr++);
683         opts = qemu_opts_create(qemu_find_opts("drive"), id, 1, NULL);
684     } while (!opts);
685 
686     p1 = strchr(filename, ':');
687     if (p1++) {
688         const char *p2;
689 
690         if (strstart(filename, "format=", &p2)) {
691             int len = MIN(p1 - p2, sizeof(fmt));
692             pstrcpy(fmt, len, p2);
693             qemu_opt_set(opts, "format", fmt, &error_abort);
694         } else if (*filename != ':') {
695             error_report("unrecognized USB mass-storage option %s", filename);
696             return NULL;
697         }
698         filename = p1;
699     }
700     if (!*filename) {
701         error_report("block device specification needed");
702         return NULL;
703     }
704     qemu_opt_set(opts, "file", filename, &error_abort);
705     qemu_opt_set(opts, "if", "none", &error_abort);
706 
707     /* create host drive */
708     dinfo = drive_new(opts, 0);
709     if (!dinfo) {
710         qemu_opts_del(opts);
711         return NULL;
712     }
713 
714     /* create guest device */
715     dev = usb_create(bus, "usb-storage");
716     qdev_prop_set_drive(&dev->qdev, "drive", blk_by_legacy_dinfo(dinfo),
717                         &err);
718     if (err) {
719         error_report_err(err);
720         object_unparent(OBJECT(dev));
721         return NULL;
722     }
723     return dev;
724 }
725 
726 static const VMStateDescription vmstate_usb_msd = {
727     .name = "usb-storage",
728     .version_id = 1,
729     .minimum_version_id = 1,
730     .fields = (VMStateField[]) {
731         VMSTATE_USB_DEVICE(dev, MSDState),
732         VMSTATE_UINT32(mode, MSDState),
733         VMSTATE_UINT32(scsi_len, MSDState),
734         VMSTATE_UINT32(scsi_off, MSDState),
735         VMSTATE_UINT32(data_len, MSDState),
736         VMSTATE_UINT32(csw.sig, MSDState),
737         VMSTATE_UINT32(csw.tag, MSDState),
738         VMSTATE_UINT32(csw.residue, MSDState),
739         VMSTATE_UINT8(csw.status, MSDState),
740         VMSTATE_END_OF_LIST()
741     }
742 };
743 
744 static Property msd_properties[] = {
745     DEFINE_BLOCK_PROPERTIES(MSDState, conf),
746     DEFINE_PROP_BIT("removable", MSDState, removable, 0, false),
747     DEFINE_PROP_END_OF_LIST(),
748 };
749 
750 static void usb_msd_class_initfn_common(ObjectClass *klass, void *data)
751 {
752     DeviceClass *dc = DEVICE_CLASS(klass);
753     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
754 
755     uc->product_desc   = "QEMU USB MSD";
756     uc->usb_desc       = &desc;
757     uc->cancel_packet  = usb_msd_cancel_io;
758     uc->handle_attach  = usb_desc_attach;
759     uc->handle_reset   = usb_msd_handle_reset;
760     uc->handle_control = usb_msd_handle_control;
761     uc->handle_data    = usb_msd_handle_data;
762     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
763     dc->fw_name = "storage";
764     dc->vmsd = &vmstate_usb_msd;
765 }
766 
767 static void usb_msd_class_storage_initfn(ObjectClass *klass, void *data)
768 {
769     DeviceClass *dc = DEVICE_CLASS(klass);
770     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
771 
772     uc->realize = usb_msd_storage_realize;
773     uc->unrealize = usb_msd_unrealize_storage;
774     dc->props = msd_properties;
775 }
776 
777 static void usb_msd_get_bootindex(Object *obj, Visitor *v, const char *name,
778                                   void *opaque, Error **errp)
779 {
780     USBDevice *dev = USB_DEVICE(obj);
781     MSDState *s = USB_STORAGE_DEV(dev);
782 
783     visit_type_int32(v, name, &s->conf.bootindex, errp);
784 }
785 
786 static void usb_msd_set_bootindex(Object *obj, Visitor *v, const char *name,
787                                   void *opaque, Error **errp)
788 {
789     USBDevice *dev = USB_DEVICE(obj);
790     MSDState *s = USB_STORAGE_DEV(dev);
791     int32_t boot_index;
792     Error *local_err = NULL;
793 
794     visit_type_int32(v, name, &boot_index, &local_err);
795     if (local_err) {
796         goto out;
797     }
798     /* check whether bootindex is present in fw_boot_order list  */
799     check_boot_index(boot_index, &local_err);
800     if (local_err) {
801         goto out;
802     }
803     /* change bootindex to a new one */
804     s->conf.bootindex = boot_index;
805 
806     if (s->scsi_dev) {
807         object_property_set_int(OBJECT(s->scsi_dev), boot_index, "bootindex",
808                                 &error_abort);
809     }
810 
811 out:
812     error_propagate(errp, local_err);
813 }
814 
815 static const TypeInfo usb_storage_dev_type_info = {
816     .name = TYPE_USB_STORAGE,
817     .parent = TYPE_USB_DEVICE,
818     .instance_size = sizeof(MSDState),
819     .abstract = true,
820     .class_init = usb_msd_class_initfn_common,
821 };
822 
823 static void usb_msd_instance_init(Object *obj)
824 {
825     object_property_add(obj, "bootindex", "int32",
826                         usb_msd_get_bootindex,
827                         usb_msd_set_bootindex, NULL, NULL, NULL);
828     object_property_set_int(obj, -1, "bootindex", NULL);
829 }
830 
831 static void usb_msd_class_bot_initfn(ObjectClass *klass, void *data)
832 {
833     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
834 
835     uc->realize = usb_msd_bot_realize;
836     uc->unrealize = usb_msd_bot_unrealize;
837     uc->attached_settable = true;
838 }
839 
840 static const TypeInfo msd_info = {
841     .name          = "usb-storage",
842     .parent        = TYPE_USB_STORAGE,
843     .class_init    = usb_msd_class_storage_initfn,
844     .instance_init = usb_msd_instance_init,
845 };
846 
847 static const TypeInfo bot_info = {
848     .name          = "usb-bot",
849     .parent        = TYPE_USB_STORAGE,
850     .class_init    = usb_msd_class_bot_initfn,
851 };
852 
853 static void usb_msd_register_types(void)
854 {
855     type_register_static(&usb_storage_dev_type_info);
856     type_register_static(&msd_info);
857     type_register_static(&bot_info);
858     usb_legacy_register("usb-storage", "disk", usb_msd_init);
859 }
860 
861 type_init(usb_msd_register_types)
862