xref: /openbmc/qemu/hw/usb/dev-mtp.c (revision 416296a9)
1 /*
2  * Media Transfer Protocol implementation, backed by host filesystem.
3  *
4  * Copyright Red Hat, Inc 2014
5  *
6  * Author:
7  *   Gerd Hoffmann <kraxel@redhat.com>
8  *
9  * This code is licensed under the GPL v2 or later.
10  */
11 
12 #include "qemu/osdep.h"
13 #include "qapi/error.h"
14 #include <wchar.h>
15 #include <dirent.h>
16 
17 #include <sys/statvfs.h>
18 #ifdef CONFIG_INOTIFY1
19 #include <sys/inotify.h>
20 #include "qapi/error.h"
21 #include "qemu/main-loop.h"
22 #endif
23 
24 #include "qemu-common.h"
25 #include "qemu/iov.h"
26 #include "trace.h"
27 #include "hw/usb.h"
28 #include "hw/usb/desc.h"
29 
30 /* ----------------------------------------------------------------------- */
31 
32 enum mtp_container_type {
33     TYPE_COMMAND  = 1,
34     TYPE_DATA     = 2,
35     TYPE_RESPONSE = 3,
36     TYPE_EVENT    = 4,
37 };
38 
39 enum mtp_code {
40     /* command codes */
41     CMD_GET_DEVICE_INFO            = 0x1001,
42     CMD_OPEN_SESSION               = 0x1002,
43     CMD_CLOSE_SESSION              = 0x1003,
44     CMD_GET_STORAGE_IDS            = 0x1004,
45     CMD_GET_STORAGE_INFO           = 0x1005,
46     CMD_GET_NUM_OBJECTS            = 0x1006,
47     CMD_GET_OBJECT_HANDLES         = 0x1007,
48     CMD_GET_OBJECT_INFO            = 0x1008,
49     CMD_GET_OBJECT                 = 0x1009,
50     CMD_GET_PARTIAL_OBJECT         = 0x101b,
51 
52     /* response codes */
53     RES_OK                         = 0x2001,
54     RES_GENERAL_ERROR              = 0x2002,
55     RES_SESSION_NOT_OPEN           = 0x2003,
56     RES_INVALID_TRANSACTION_ID     = 0x2004,
57     RES_OPERATION_NOT_SUPPORTED    = 0x2005,
58     RES_PARAMETER_NOT_SUPPORTED    = 0x2006,
59     RES_INCOMPLETE_TRANSFER        = 0x2007,
60     RES_INVALID_STORAGE_ID         = 0x2008,
61     RES_INVALID_OBJECT_HANDLE      = 0x2009,
62     RES_SPEC_BY_FORMAT_UNSUPPORTED = 0x2014,
63     RES_INVALID_PARENT_OBJECT      = 0x201a,
64     RES_INVALID_PARAMETER          = 0x201d,
65     RES_SESSION_ALREADY_OPEN       = 0x201e,
66 
67     /* format codes */
68     FMT_UNDEFINED_OBJECT           = 0x3000,
69     FMT_ASSOCIATION                = 0x3001,
70 
71     /* event codes */
72     EVT_OBJ_ADDED                  = 0x4002,
73     EVT_OBJ_REMOVED                = 0x4003,
74     EVT_OBJ_INFO_CHANGED           = 0x4007,
75 };
76 
77 typedef struct {
78     uint32_t length;
79     uint16_t type;
80     uint16_t code;
81     uint32_t trans;
82 } QEMU_PACKED mtp_container;
83 
84 /* ----------------------------------------------------------------------- */
85 
86 typedef struct MTPState MTPState;
87 typedef struct MTPControl MTPControl;
88 typedef struct MTPData MTPData;
89 typedef struct MTPObject MTPObject;
90 
91 enum {
92     EP_DATA_IN = 1,
93     EP_DATA_OUT,
94     EP_EVENT,
95 };
96 
97 #ifdef CONFIG_INOTIFY1
98 typedef struct MTPMonEntry MTPMonEntry;
99 
100 struct MTPMonEntry {
101     uint32_t event;
102     uint32_t handle;
103 
104     QTAILQ_ENTRY(MTPMonEntry) next;
105 };
106 #endif
107 
108 struct MTPControl {
109     uint16_t     code;
110     uint32_t     trans;
111     int          argc;
112     uint32_t     argv[5];
113 };
114 
115 struct MTPData {
116     uint16_t     code;
117     uint32_t     trans;
118     uint32_t     offset;
119     uint32_t     length;
120     uint32_t     alloc;
121     uint8_t      *data;
122     bool         first;
123     int          fd;
124 };
125 
126 struct MTPObject {
127     uint32_t     handle;
128     uint16_t     format;
129     char         *name;
130     char         *path;
131     struct stat  stat;
132 #ifdef CONFIG_INOTIFY1
133     /* inotify watch cookie */
134     int          watchfd;
135 #endif
136     MTPObject    *parent;
137     uint32_t     nchildren;
138     QLIST_HEAD(, MTPObject) children;
139     QLIST_ENTRY(MTPObject) list;
140     bool         have_children;
141     QTAILQ_ENTRY(MTPObject) next;
142 };
143 
144 struct MTPState {
145     USBDevice    dev;
146     char         *root;
147     char         *desc;
148     uint32_t     flags;
149 
150     MTPData      *data_in;
151     MTPData      *data_out;
152     MTPControl   *result;
153     uint32_t     session;
154     uint32_t     next_handle;
155 
156     QTAILQ_HEAD(, MTPObject) objects;
157 #ifdef CONFIG_INOTIFY1
158     /* inotify descriptor */
159     int          inotifyfd;
160     QTAILQ_HEAD(events, MTPMonEntry) events;
161 #endif
162 };
163 
164 #define TYPE_USB_MTP "usb-mtp"
165 #define USB_MTP(obj) OBJECT_CHECK(MTPState, (obj), TYPE_USB_MTP)
166 
167 #define QEMU_STORAGE_ID 0x00010001
168 
169 #define MTP_FLAG_WRITABLE 0
170 
171 #define FLAG_SET(_mtp, _flag)  ((_mtp)->flags & (1 << (_flag)))
172 
173 /* ----------------------------------------------------------------------- */
174 
175 #define MTP_MANUFACTURER  "QEMU"
176 #define MTP_PRODUCT       "QEMU filesharing"
177 
178 enum {
179     STR_MANUFACTURER = 1,
180     STR_PRODUCT,
181     STR_SERIALNUMBER,
182     STR_MTP,
183     STR_CONFIG_FULL,
184     STR_CONFIG_HIGH,
185     STR_CONFIG_SUPER,
186 };
187 
188 static const USBDescStrings desc_strings = {
189     [STR_MANUFACTURER] = MTP_MANUFACTURER,
190     [STR_PRODUCT]      = MTP_PRODUCT,
191     [STR_SERIALNUMBER] = "34617",
192     [STR_MTP]          = "MTP",
193     [STR_CONFIG_FULL]  = "Full speed config (usb 1.1)",
194     [STR_CONFIG_HIGH]  = "High speed config (usb 2.0)",
195     [STR_CONFIG_SUPER] = "Super speed config (usb 3.0)",
196 };
197 
198 static const USBDescIface desc_iface_full = {
199     .bInterfaceNumber              = 0,
200     .bNumEndpoints                 = 3,
201     .bInterfaceClass               = USB_CLASS_STILL_IMAGE,
202     .bInterfaceSubClass            = 0x01,
203     .bInterfaceProtocol            = 0x01,
204     .iInterface                    = STR_MTP,
205     .eps = (USBDescEndpoint[]) {
206         {
207             .bEndpointAddress      = USB_DIR_IN | EP_DATA_IN,
208             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
209             .wMaxPacketSize        = 64,
210         },{
211             .bEndpointAddress      = USB_DIR_OUT | EP_DATA_OUT,
212             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
213             .wMaxPacketSize        = 64,
214         },{
215             .bEndpointAddress      = USB_DIR_IN | EP_EVENT,
216             .bmAttributes          = USB_ENDPOINT_XFER_INT,
217             .wMaxPacketSize        = 64,
218             .bInterval             = 0x0a,
219         },
220     }
221 };
222 
223 static const USBDescDevice desc_device_full = {
224     .bcdUSB                        = 0x0200,
225     .bMaxPacketSize0               = 8,
226     .bNumConfigurations            = 1,
227     .confs = (USBDescConfig[]) {
228         {
229             .bNumInterfaces        = 1,
230             .bConfigurationValue   = 1,
231             .iConfiguration        = STR_CONFIG_FULL,
232             .bmAttributes          = USB_CFG_ATT_ONE | USB_CFG_ATT_WAKEUP,
233             .bMaxPower             = 2,
234             .nif = 1,
235             .ifs = &desc_iface_full,
236         },
237     },
238 };
239 
240 static const USBDescIface desc_iface_high = {
241     .bInterfaceNumber              = 0,
242     .bNumEndpoints                 = 3,
243     .bInterfaceClass               = USB_CLASS_STILL_IMAGE,
244     .bInterfaceSubClass            = 0x01,
245     .bInterfaceProtocol            = 0x01,
246     .iInterface                    = STR_MTP,
247     .eps = (USBDescEndpoint[]) {
248         {
249             .bEndpointAddress      = USB_DIR_IN | EP_DATA_IN,
250             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
251             .wMaxPacketSize        = 512,
252         },{
253             .bEndpointAddress      = USB_DIR_OUT | EP_DATA_OUT,
254             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
255             .wMaxPacketSize        = 512,
256         },{
257             .bEndpointAddress      = USB_DIR_IN | EP_EVENT,
258             .bmAttributes          = USB_ENDPOINT_XFER_INT,
259             .wMaxPacketSize        = 64,
260             .bInterval             = 0x0a,
261         },
262     }
263 };
264 
265 static const USBDescDevice desc_device_high = {
266     .bcdUSB                        = 0x0200,
267     .bMaxPacketSize0               = 64,
268     .bNumConfigurations            = 1,
269     .confs = (USBDescConfig[]) {
270         {
271             .bNumInterfaces        = 1,
272             .bConfigurationValue   = 1,
273             .iConfiguration        = STR_CONFIG_HIGH,
274             .bmAttributes          = USB_CFG_ATT_ONE | USB_CFG_ATT_WAKEUP,
275             .bMaxPower             = 2,
276             .nif = 1,
277             .ifs = &desc_iface_high,
278         },
279     },
280 };
281 
282 static const USBDescMSOS desc_msos = {
283     .CompatibleID = "MTP",
284     .SelectiveSuspendEnabled = true,
285 };
286 
287 static const USBDesc desc = {
288     .id = {
289         .idVendor          = 0x46f4, /* CRC16() of "QEMU" */
290         .idProduct         = 0x0004,
291         .bcdDevice         = 0,
292         .iManufacturer     = STR_MANUFACTURER,
293         .iProduct          = STR_PRODUCT,
294         .iSerialNumber     = STR_SERIALNUMBER,
295     },
296     .full  = &desc_device_full,
297     .high  = &desc_device_high,
298     .str   = desc_strings,
299     .msos  = &desc_msos,
300 };
301 
302 /* ----------------------------------------------------------------------- */
303 
304 static MTPObject *usb_mtp_object_alloc(MTPState *s, uint32_t handle,
305                                        MTPObject *parent, char *name)
306 {
307     MTPObject *o = g_new0(MTPObject, 1);
308 
309     if (name[0] == '.') {
310         goto ignore;
311     }
312 
313     o->handle = handle;
314     o->parent = parent;
315     o->name = g_strdup(name);
316     if (parent == NULL) {
317         o->path = g_strdup(name);
318     } else {
319         o->path = g_strdup_printf("%s/%s", parent->path, name);
320     }
321 
322     if (lstat(o->path, &o->stat) != 0) {
323         goto ignore;
324     }
325     if (S_ISREG(o->stat.st_mode)) {
326         o->format = FMT_UNDEFINED_OBJECT;
327     } else if (S_ISDIR(o->stat.st_mode)) {
328         o->format = FMT_ASSOCIATION;
329     } else {
330         goto ignore;
331     }
332 
333     if (access(o->path, R_OK) != 0) {
334         goto ignore;
335     }
336 
337     trace_usb_mtp_object_alloc(s->dev.addr, o->handle, o->path);
338 
339     QTAILQ_INSERT_TAIL(&s->objects, o, next);
340     return o;
341 
342 ignore:
343     g_free(o->name);
344     g_free(o->path);
345     g_free(o);
346     return NULL;
347 }
348 
349 static void usb_mtp_object_free(MTPState *s, MTPObject *o)
350 {
351     MTPObject *iter;
352 
353     if (!o) {
354         return;
355     }
356 
357     trace_usb_mtp_object_free(s->dev.addr, o->handle, o->path);
358 
359     QTAILQ_REMOVE(&s->objects, o, next);
360     if (o->parent) {
361         QLIST_REMOVE(o, list);
362         o->parent->nchildren--;
363     }
364 
365     while (!QLIST_EMPTY(&o->children)) {
366         iter = QLIST_FIRST(&o->children);
367         usb_mtp_object_free(s, iter);
368     }
369     g_free(o->name);
370     g_free(o->path);
371     g_free(o);
372 }
373 
374 static MTPObject *usb_mtp_object_lookup(MTPState *s, uint32_t handle)
375 {
376     MTPObject *o;
377 
378     QTAILQ_FOREACH(o, &s->objects, next) {
379         if (o->handle == handle) {
380             return o;
381         }
382     }
383     return NULL;
384 }
385 
386 static MTPObject *usb_mtp_add_child(MTPState *s, MTPObject *o,
387                                     char *name)
388 {
389     MTPObject *child =
390         usb_mtp_object_alloc(s, s->next_handle++, o, name);
391 
392     if (child) {
393         trace_usb_mtp_add_child(s->dev.addr, child->handle, child->path);
394         QLIST_INSERT_HEAD(&o->children, child, list);
395         o->nchildren++;
396 
397         if (child->format == FMT_ASSOCIATION) {
398             QLIST_INIT(&child->children);
399         }
400     }
401 
402     return child;
403 }
404 
405 #ifdef CONFIG_INOTIFY1
406 static MTPObject *usb_mtp_object_lookup_name(MTPObject *parent,
407                                              char *name, int len)
408 {
409     MTPObject *iter;
410 
411     QLIST_FOREACH(iter, &parent->children, list) {
412         if (strncmp(iter->name, name, len) == 0) {
413             return iter;
414         }
415     }
416 
417     return NULL;
418 }
419 
420 static MTPObject *usb_mtp_object_lookup_wd(MTPState *s, int wd)
421 {
422     MTPObject *iter;
423 
424     QTAILQ_FOREACH(iter, &s->objects, next) {
425         if (iter->watchfd == wd) {
426             return iter;
427         }
428     }
429 
430     return NULL;
431 }
432 
433 static void inotify_watchfn(void *arg)
434 {
435     MTPState *s = arg;
436     ssize_t bytes;
437     /* From the man page: atleast one event can be read */
438     int pos;
439     char buf[sizeof(struct inotify_event) + NAME_MAX + 1];
440 
441     for (;;) {
442         bytes = read(s->inotifyfd, buf, sizeof(buf));
443         pos = 0;
444 
445         if (bytes <= 0) {
446             /* Better luck next time */
447             return;
448         }
449 
450         /*
451          * TODO: Ignore initiator initiated events.
452          * For now we are good because the store is RO
453          */
454         while (bytes > 0) {
455             char *p = buf + pos;
456             struct inotify_event *event = (struct inotify_event *)p;
457             int watchfd = 0;
458             uint32_t mask = event->mask & (IN_CREATE | IN_DELETE |
459                                            IN_MODIFY | IN_IGNORED);
460             MTPObject *parent = usb_mtp_object_lookup_wd(s, event->wd);
461             MTPMonEntry *entry = NULL;
462             MTPObject *o;
463 
464             pos = pos + sizeof(struct inotify_event) + event->len;
465             bytes = bytes - pos;
466 
467             if (!parent) {
468                 continue;
469             }
470 
471             switch (mask) {
472             case IN_CREATE:
473                 if (usb_mtp_object_lookup_name
474                     (parent, event->name, event->len)) {
475                     /* Duplicate create event */
476                     continue;
477                 }
478                 entry = g_new0(MTPMonEntry, 1);
479                 entry->handle = s->next_handle;
480                 entry->event = EVT_OBJ_ADDED;
481                 o = usb_mtp_add_child(s, parent, event->name);
482                 if (!o) {
483                     g_free(entry);
484                     continue;
485                 }
486                 o->watchfd = watchfd;
487                 trace_usb_mtp_inotify_event(s->dev.addr, event->name,
488                                             event->mask, "Obj Added");
489                 break;
490 
491             case IN_DELETE:
492                 /*
493                  * The kernel issues a IN_IGNORED event
494                  * when a dir containing a watchpoint is
495                  * deleted, so we don't have to delete the
496                  * watchpoint
497                  */
498                 o = usb_mtp_object_lookup_name(parent, event->name, event->len);
499                 if (!o) {
500                     continue;
501                 }
502                 entry = g_new0(MTPMonEntry, 1);
503                 entry->handle = o->handle;
504                 entry->event = EVT_OBJ_REMOVED;
505                 trace_usb_mtp_inotify_event(s->dev.addr, o->path,
506                                       event->mask, "Obj Deleted");
507                 usb_mtp_object_free(s, o);
508                 break;
509 
510             case IN_MODIFY:
511                 o = usb_mtp_object_lookup_name(parent, event->name, event->len);
512                 if (!o) {
513                     continue;
514                 }
515                 entry = g_new0(MTPMonEntry, 1);
516                 entry->handle = o->handle;
517                 entry->event = EVT_OBJ_INFO_CHANGED;
518                 trace_usb_mtp_inotify_event(s->dev.addr, o->path,
519                                       event->mask, "Obj Modified");
520                 break;
521 
522             case IN_IGNORED:
523                 o = usb_mtp_object_lookup_name(parent, event->name, event->len);
524                 trace_usb_mtp_inotify_event(s->dev.addr, o->path,
525                                       event->mask, "Obj ignored");
526                 break;
527 
528             default:
529                 fprintf(stderr, "usb-mtp: failed to parse inotify event\n");
530                 continue;
531             }
532 
533             if (entry) {
534                 QTAILQ_INSERT_HEAD(&s->events, entry, next);
535             }
536         }
537     }
538 }
539 
540 static int usb_mtp_inotify_init(MTPState *s)
541 {
542     int fd;
543 
544     fd = inotify_init1(IN_NONBLOCK);
545     if (fd == -1) {
546         return 1;
547     }
548 
549     QTAILQ_INIT(&s->events);
550     s->inotifyfd = fd;
551 
552     qemu_set_fd_handler(fd, inotify_watchfn, NULL, s);
553 
554     return 0;
555 }
556 
557 static void usb_mtp_inotify_cleanup(MTPState *s)
558 {
559     MTPMonEntry *e, *p;
560 
561     if (!s->inotifyfd) {
562         return;
563     }
564 
565     qemu_set_fd_handler(s->inotifyfd, NULL, NULL, s);
566     close(s->inotifyfd);
567 
568     QTAILQ_FOREACH_SAFE(e, &s->events, next, p) {
569         QTAILQ_REMOVE(&s->events, e, next);
570         g_free(e);
571     }
572 }
573 
574 static int usb_mtp_add_watch(int inotifyfd, char *path)
575 {
576     uint32_t mask = IN_CREATE | IN_DELETE | IN_MODIFY |
577         IN_ISDIR;
578 
579     return inotify_add_watch(inotifyfd, path, mask);
580 }
581 #endif
582 
583 static void usb_mtp_object_readdir(MTPState *s, MTPObject *o)
584 {
585     struct dirent *entry;
586     DIR *dir;
587 
588     if (o->have_children) {
589         return;
590     }
591     o->have_children = true;
592 
593     dir = opendir(o->path);
594     if (!dir) {
595         return;
596     }
597 #ifdef CONFIG_INOTIFY1
598     int watchfd = usb_mtp_add_watch(s->inotifyfd, o->path);
599     if (watchfd == -1) {
600         fprintf(stderr, "usb-mtp: failed to add watch for %s\n", o->path);
601     } else {
602         trace_usb_mtp_inotify_event(s->dev.addr, o->path,
603                                     0, "Watch Added");
604         o->watchfd = watchfd;
605     }
606 #endif
607     while ((entry = readdir(dir)) != NULL) {
608         usb_mtp_add_child(s, o, entry->d_name);
609     }
610     closedir(dir);
611 }
612 
613 /* ----------------------------------------------------------------------- */
614 
615 static MTPData *usb_mtp_data_alloc(MTPControl *c)
616 {
617     MTPData *data = g_new0(MTPData, 1);
618 
619     data->code  = c->code;
620     data->trans = c->trans;
621     data->fd    = -1;
622     data->first = true;
623     return data;
624 }
625 
626 static void usb_mtp_data_free(MTPData *data)
627 {
628     if (data == NULL) {
629         return;
630     }
631     if (data->fd != -1) {
632         close(data->fd);
633     }
634     g_free(data->data);
635     g_free(data);
636 }
637 
638 static void usb_mtp_realloc(MTPData *data, uint32_t bytes)
639 {
640     if (data->length + bytes <= data->alloc) {
641         return;
642     }
643     data->alloc = (data->length + bytes + 0xff) & ~0xff;
644     data->data  = g_realloc(data->data, data->alloc);
645 }
646 
647 static void usb_mtp_add_u8(MTPData *data, uint8_t val)
648 {
649     usb_mtp_realloc(data, 1);
650     data->data[data->length++] = val;
651 }
652 
653 static void usb_mtp_add_u16(MTPData *data, uint16_t val)
654 {
655     usb_mtp_realloc(data, 2);
656     data->data[data->length++] = (val >> 0) & 0xff;
657     data->data[data->length++] = (val >> 8) & 0xff;
658 }
659 
660 static void usb_mtp_add_u32(MTPData *data, uint32_t val)
661 {
662     usb_mtp_realloc(data, 4);
663     data->data[data->length++] = (val >>  0) & 0xff;
664     data->data[data->length++] = (val >>  8) & 0xff;
665     data->data[data->length++] = (val >> 16) & 0xff;
666     data->data[data->length++] = (val >> 24) & 0xff;
667 }
668 
669 static void usb_mtp_add_u64(MTPData *data, uint64_t val)
670 {
671     usb_mtp_realloc(data, 8);
672     data->data[data->length++] = (val >>  0) & 0xff;
673     data->data[data->length++] = (val >>  8) & 0xff;
674     data->data[data->length++] = (val >> 16) & 0xff;
675     data->data[data->length++] = (val >> 24) & 0xff;
676     data->data[data->length++] = (val >> 32) & 0xff;
677     data->data[data->length++] = (val >> 40) & 0xff;
678     data->data[data->length++] = (val >> 48) & 0xff;
679     data->data[data->length++] = (val >> 56) & 0xff;
680 }
681 
682 static void usb_mtp_add_u16_array(MTPData *data, uint32_t len,
683                                   const uint16_t *vals)
684 {
685     int i;
686 
687     usb_mtp_add_u32(data, len);
688     for (i = 0; i < len; i++) {
689         usb_mtp_add_u16(data, vals[i]);
690     }
691 }
692 
693 static void usb_mtp_add_u32_array(MTPData *data, uint32_t len,
694                                   const uint32_t *vals)
695 {
696     int i;
697 
698     usb_mtp_add_u32(data, len);
699     for (i = 0; i < len; i++) {
700         usb_mtp_add_u32(data, vals[i]);
701     }
702 }
703 
704 static void usb_mtp_add_wstr(MTPData *data, const wchar_t *str)
705 {
706     uint32_t len = wcslen(str);
707     int i;
708 
709     if (len > 0) {
710         len++; /* include terminating L'\0' */
711     }
712 
713     usb_mtp_add_u8(data, len);
714     for (i = 0; i < len; i++) {
715         usb_mtp_add_u16(data, str[i]);
716     }
717 }
718 
719 static void usb_mtp_add_str(MTPData *data, const char *str)
720 {
721     uint32_t len = strlen(str)+1;
722     wchar_t *wstr = g_new(wchar_t, len);
723     size_t ret;
724 
725     ret = mbstowcs(wstr, str, len);
726     if (ret == -1) {
727         usb_mtp_add_wstr(data, L"Oops");
728     } else {
729         usb_mtp_add_wstr(data, wstr);
730     }
731 
732     g_free(wstr);
733 }
734 
735 static void usb_mtp_add_time(MTPData *data, time_t time)
736 {
737     char buf[16];
738     struct tm tm;
739 
740     gmtime_r(&time, &tm);
741     strftime(buf, sizeof(buf), "%Y%m%dT%H%M%S", &tm);
742     usb_mtp_add_str(data, buf);
743 }
744 
745 /* ----------------------------------------------------------------------- */
746 
747 static void usb_mtp_queue_result(MTPState *s, uint16_t code, uint32_t trans,
748                                  int argc, uint32_t arg0, uint32_t arg1)
749 {
750     MTPControl *c = g_new0(MTPControl, 1);
751 
752     c->code  = code;
753     c->trans = trans;
754     c->argc  = argc;
755     if (argc > 0) {
756         c->argv[0] = arg0;
757     }
758     if (argc > 1) {
759         c->argv[1] = arg1;
760     }
761 
762     assert(s->result == NULL);
763     s->result = c;
764 }
765 
766 /* ----------------------------------------------------------------------- */
767 
768 static MTPData *usb_mtp_get_device_info(MTPState *s, MTPControl *c)
769 {
770     static const uint16_t ops[] = {
771         CMD_GET_DEVICE_INFO,
772         CMD_OPEN_SESSION,
773         CMD_CLOSE_SESSION,
774         CMD_GET_STORAGE_IDS,
775         CMD_GET_STORAGE_INFO,
776         CMD_GET_NUM_OBJECTS,
777         CMD_GET_OBJECT_HANDLES,
778         CMD_GET_OBJECT_INFO,
779         CMD_GET_OBJECT,
780         CMD_GET_PARTIAL_OBJECT,
781     };
782     static const uint16_t fmt[] = {
783         FMT_UNDEFINED_OBJECT,
784         FMT_ASSOCIATION,
785     };
786     MTPData *d = usb_mtp_data_alloc(c);
787 
788     trace_usb_mtp_op_get_device_info(s->dev.addr);
789 
790     usb_mtp_add_u16(d, 100);
791     usb_mtp_add_u32(d, 0x00000006);
792     usb_mtp_add_u16(d, 0x0064);
793     usb_mtp_add_wstr(d, L"");
794     usb_mtp_add_u16(d, 0x0000);
795 
796     usb_mtp_add_u16_array(d, ARRAY_SIZE(ops), ops);
797     usb_mtp_add_u16_array(d, 0, NULL);
798     usb_mtp_add_u16_array(d, 0, NULL);
799     usb_mtp_add_u16_array(d, 0, NULL);
800     usb_mtp_add_u16_array(d, ARRAY_SIZE(fmt), fmt);
801 
802     usb_mtp_add_wstr(d, L"" MTP_MANUFACTURER);
803     usb_mtp_add_wstr(d, L"" MTP_PRODUCT);
804     usb_mtp_add_wstr(d, L"0.1");
805     usb_mtp_add_wstr(d, L"0123456789abcdef0123456789abcdef");
806 
807     return d;
808 }
809 
810 static MTPData *usb_mtp_get_storage_ids(MTPState *s, MTPControl *c)
811 {
812     static const uint32_t ids[] = {
813         QEMU_STORAGE_ID,
814     };
815     MTPData *d = usb_mtp_data_alloc(c);
816 
817     trace_usb_mtp_op_get_storage_ids(s->dev.addr);
818 
819     usb_mtp_add_u32_array(d, ARRAY_SIZE(ids), ids);
820 
821     return d;
822 }
823 
824 static MTPData *usb_mtp_get_storage_info(MTPState *s, MTPControl *c)
825 {
826     MTPData *d = usb_mtp_data_alloc(c);
827     struct statvfs buf;
828     int rc;
829 
830     trace_usb_mtp_op_get_storage_info(s->dev.addr);
831 
832     if (FLAG_SET(s, MTP_FLAG_WRITABLE)) {
833         usb_mtp_add_u16(d, 0x0003);
834         usb_mtp_add_u16(d, 0x0002);
835         usb_mtp_add_u16(d, 0x0000);
836     } else {
837         usb_mtp_add_u16(d, 0x0001);
838         usb_mtp_add_u16(d, 0x0002);
839         usb_mtp_add_u16(d, 0x0001);
840     }
841 
842     rc = statvfs(s->root, &buf);
843     if (rc == 0) {
844         usb_mtp_add_u64(d, (uint64_t)buf.f_frsize * buf.f_blocks);
845         usb_mtp_add_u64(d, (uint64_t)buf.f_bavail * buf.f_blocks);
846         usb_mtp_add_u32(d, buf.f_ffree);
847     } else {
848         usb_mtp_add_u64(d, 0xffffffff);
849         usb_mtp_add_u64(d, 0xffffffff);
850         usb_mtp_add_u32(d, 0xffffffff);
851     }
852 
853     usb_mtp_add_str(d, s->desc);
854     usb_mtp_add_wstr(d, L"123456789abcdef");
855     return d;
856 }
857 
858 static MTPData *usb_mtp_get_object_handles(MTPState *s, MTPControl *c,
859                                            MTPObject *o)
860 {
861     MTPData *d = usb_mtp_data_alloc(c);
862     uint32_t i = 0, handles[o->nchildren];
863     MTPObject *iter;
864 
865     trace_usb_mtp_op_get_object_handles(s->dev.addr, o->handle, o->path);
866 
867     QLIST_FOREACH(iter, &o->children, list) {
868         handles[i++] = iter->handle;
869     }
870     assert(i == o->nchildren);
871     usb_mtp_add_u32_array(d, o->nchildren, handles);
872 
873     return d;
874 }
875 
876 static MTPData *usb_mtp_get_object_info(MTPState *s, MTPControl *c,
877                                         MTPObject *o)
878 {
879     MTPData *d = usb_mtp_data_alloc(c);
880 
881     trace_usb_mtp_op_get_object_info(s->dev.addr, o->handle, o->path);
882 
883     usb_mtp_add_u32(d, QEMU_STORAGE_ID);
884     usb_mtp_add_u16(d, o->format);
885     usb_mtp_add_u16(d, 0);
886     usb_mtp_add_u32(d, o->stat.st_size);
887 
888     usb_mtp_add_u16(d, 0);
889     usb_mtp_add_u32(d, 0);
890     usb_mtp_add_u32(d, 0);
891     usb_mtp_add_u32(d, 0);
892     usb_mtp_add_u32(d, 0);
893     usb_mtp_add_u32(d, 0);
894     usb_mtp_add_u32(d, 0);
895 
896     if (o->parent) {
897         usb_mtp_add_u32(d, o->parent->handle);
898     } else {
899         usb_mtp_add_u32(d, 0);
900     }
901     if (o->format == FMT_ASSOCIATION) {
902         usb_mtp_add_u16(d, 0x0001);
903         usb_mtp_add_u32(d, 0x00000001);
904         usb_mtp_add_u32(d, 0);
905     } else {
906         usb_mtp_add_u16(d, 0);
907         usb_mtp_add_u32(d, 0);
908         usb_mtp_add_u32(d, 0);
909     }
910 
911     usb_mtp_add_str(d, o->name);
912     usb_mtp_add_time(d, o->stat.st_ctime);
913     usb_mtp_add_time(d, o->stat.st_mtime);
914     usb_mtp_add_wstr(d, L"");
915 
916     return d;
917 }
918 
919 static MTPData *usb_mtp_get_object(MTPState *s, MTPControl *c,
920                                    MTPObject *o)
921 {
922     MTPData *d = usb_mtp_data_alloc(c);
923 
924     trace_usb_mtp_op_get_object(s->dev.addr, o->handle, o->path);
925 
926     d->fd = open(o->path, O_RDONLY);
927     if (d->fd == -1) {
928         usb_mtp_data_free(d);
929         return NULL;
930     }
931     d->length = o->stat.st_size;
932     d->alloc  = 512;
933     d->data   = g_malloc(d->alloc);
934     return d;
935 }
936 
937 static MTPData *usb_mtp_get_partial_object(MTPState *s, MTPControl *c,
938                                            MTPObject *o)
939 {
940     MTPData *d = usb_mtp_data_alloc(c);
941     off_t offset;
942 
943     trace_usb_mtp_op_get_partial_object(s->dev.addr, o->handle, o->path,
944                                         c->argv[1], c->argv[2]);
945 
946     d->fd = open(o->path, O_RDONLY);
947     if (d->fd == -1) {
948         usb_mtp_data_free(d);
949         return NULL;
950     }
951 
952     offset = c->argv[1];
953     if (offset > o->stat.st_size) {
954         offset = o->stat.st_size;
955     }
956     if (lseek(d->fd, offset, SEEK_SET) < 0) {
957         usb_mtp_data_free(d);
958         return NULL;
959     }
960 
961     d->length = c->argv[2];
962     if (d->length > o->stat.st_size - offset) {
963         d->length = o->stat.st_size - offset;
964     }
965 
966     return d;
967 }
968 
969 static void usb_mtp_command(MTPState *s, MTPControl *c)
970 {
971     MTPData *data_in = NULL;
972     MTPObject *o;
973     uint32_t nres = 0, res0 = 0;
974 
975     /* sanity checks */
976     if (c->code >= CMD_CLOSE_SESSION && s->session == 0) {
977         usb_mtp_queue_result(s, RES_SESSION_NOT_OPEN,
978                              c->trans, 0, 0, 0);
979         return;
980     }
981 
982     /* process commands */
983     switch (c->code) {
984     case CMD_GET_DEVICE_INFO:
985         data_in = usb_mtp_get_device_info(s, c);
986         break;
987     case CMD_OPEN_SESSION:
988         if (s->session) {
989             usb_mtp_queue_result(s, RES_SESSION_ALREADY_OPEN,
990                                  c->trans, 1, s->session, 0);
991             return;
992         }
993         if (c->argv[0] == 0) {
994             usb_mtp_queue_result(s, RES_INVALID_PARAMETER,
995                                  c->trans, 0, 0, 0);
996             return;
997         }
998         trace_usb_mtp_op_open_session(s->dev.addr);
999         s->session = c->argv[0];
1000         usb_mtp_object_alloc(s, s->next_handle++, NULL, s->root);
1001 #ifdef CONFIG_INOTIFY1
1002         if (usb_mtp_inotify_init(s)) {
1003             fprintf(stderr, "usb-mtp: file monitoring init failed\n");
1004         }
1005 #endif
1006         break;
1007     case CMD_CLOSE_SESSION:
1008         trace_usb_mtp_op_close_session(s->dev.addr);
1009         s->session = 0;
1010         s->next_handle = 0;
1011 #ifdef CONFIG_INOTIFY1
1012         usb_mtp_inotify_cleanup(s);
1013 #endif
1014         usb_mtp_object_free(s, QTAILQ_FIRST(&s->objects));
1015         assert(QTAILQ_EMPTY(&s->objects));
1016         break;
1017     case CMD_GET_STORAGE_IDS:
1018         data_in = usb_mtp_get_storage_ids(s, c);
1019         break;
1020     case CMD_GET_STORAGE_INFO:
1021         if (c->argv[0] != QEMU_STORAGE_ID &&
1022             c->argv[0] != 0xffffffff) {
1023             usb_mtp_queue_result(s, RES_INVALID_STORAGE_ID,
1024                                  c->trans, 0, 0, 0);
1025             return;
1026         }
1027         data_in = usb_mtp_get_storage_info(s, c);
1028         break;
1029     case CMD_GET_NUM_OBJECTS:
1030     case CMD_GET_OBJECT_HANDLES:
1031         if (c->argv[0] != QEMU_STORAGE_ID &&
1032             c->argv[0] != 0xffffffff) {
1033             usb_mtp_queue_result(s, RES_INVALID_STORAGE_ID,
1034                                  c->trans, 0, 0, 0);
1035             return;
1036         }
1037         if (c->argv[1] != 0x00000000) {
1038             usb_mtp_queue_result(s, RES_SPEC_BY_FORMAT_UNSUPPORTED,
1039                                  c->trans, 0, 0, 0);
1040             return;
1041         }
1042         if (c->argv[2] == 0x00000000 ||
1043             c->argv[2] == 0xffffffff) {
1044             o = QTAILQ_FIRST(&s->objects);
1045         } else {
1046             o = usb_mtp_object_lookup(s, c->argv[2]);
1047         }
1048         if (o == NULL) {
1049             usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1050                                  c->trans, 0, 0, 0);
1051             return;
1052         }
1053         if (o->format != FMT_ASSOCIATION) {
1054             usb_mtp_queue_result(s, RES_INVALID_PARENT_OBJECT,
1055                                  c->trans, 0, 0, 0);
1056             return;
1057         }
1058         usb_mtp_object_readdir(s, o);
1059         if (c->code == CMD_GET_NUM_OBJECTS) {
1060             trace_usb_mtp_op_get_num_objects(s->dev.addr, o->handle, o->path);
1061             nres = 1;
1062             res0 = o->nchildren;
1063         } else {
1064             data_in = usb_mtp_get_object_handles(s, c, o);
1065         }
1066         break;
1067     case CMD_GET_OBJECT_INFO:
1068         o = usb_mtp_object_lookup(s, c->argv[0]);
1069         if (o == NULL) {
1070             usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1071                                  c->trans, 0, 0, 0);
1072             return;
1073         }
1074         data_in = usb_mtp_get_object_info(s, c, o);
1075         break;
1076     case CMD_GET_OBJECT:
1077         o = usb_mtp_object_lookup(s, c->argv[0]);
1078         if (o == NULL) {
1079             usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1080                                  c->trans, 0, 0, 0);
1081             return;
1082         }
1083         if (o->format == FMT_ASSOCIATION) {
1084             usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1085                                  c->trans, 0, 0, 0);
1086             return;
1087         }
1088         data_in = usb_mtp_get_object(s, c, o);
1089         if (data_in == NULL) {
1090             usb_mtp_queue_result(s, RES_GENERAL_ERROR,
1091                                  c->trans, 0, 0, 0);
1092             return;
1093         }
1094         break;
1095     case CMD_GET_PARTIAL_OBJECT:
1096         o = usb_mtp_object_lookup(s, c->argv[0]);
1097         if (o == NULL) {
1098             usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1099                                  c->trans, 0, 0, 0);
1100             return;
1101         }
1102         if (o->format == FMT_ASSOCIATION) {
1103             usb_mtp_queue_result(s, RES_INVALID_OBJECT_HANDLE,
1104                                  c->trans, 0, 0, 0);
1105             return;
1106         }
1107         data_in = usb_mtp_get_partial_object(s, c, o);
1108         if (data_in == NULL) {
1109             usb_mtp_queue_result(s, RES_GENERAL_ERROR,
1110                                  c->trans, 0, 0, 0);
1111             return;
1112         }
1113         nres = 1;
1114         res0 = data_in->length;
1115         break;
1116     default:
1117         trace_usb_mtp_op_unknown(s->dev.addr, c->code);
1118         usb_mtp_queue_result(s, RES_OPERATION_NOT_SUPPORTED,
1119                              c->trans, 0, 0, 0);
1120         return;
1121     }
1122 
1123     /* return results on success */
1124     if (data_in) {
1125         assert(s->data_in == NULL);
1126         s->data_in = data_in;
1127     }
1128     usb_mtp_queue_result(s, RES_OK, c->trans, nres, res0, 0);
1129 }
1130 
1131 /* ----------------------------------------------------------------------- */
1132 
1133 static void usb_mtp_handle_reset(USBDevice *dev)
1134 {
1135     MTPState *s = USB_MTP(dev);
1136 
1137     trace_usb_mtp_reset(s->dev.addr);
1138 
1139 #ifdef CONFIG_INOTIFY1
1140     usb_mtp_inotify_cleanup(s);
1141 #endif
1142     usb_mtp_object_free(s, QTAILQ_FIRST(&s->objects));
1143     s->session = 0;
1144     usb_mtp_data_free(s->data_in);
1145     s->data_in = NULL;
1146     usb_mtp_data_free(s->data_out);
1147     s->data_out = NULL;
1148     g_free(s->result);
1149     s->result = NULL;
1150 }
1151 
1152 static void usb_mtp_handle_control(USBDevice *dev, USBPacket *p,
1153                                    int request, int value, int index,
1154                                    int length, uint8_t *data)
1155 {
1156     int ret;
1157 
1158     ret = usb_desc_handle_control(dev, p, request, value, index, length, data);
1159     if (ret >= 0) {
1160         return;
1161     }
1162 
1163     trace_usb_mtp_stall(dev->addr, "unknown control request");
1164     p->status = USB_RET_STALL;
1165 }
1166 
1167 static void usb_mtp_cancel_packet(USBDevice *dev, USBPacket *p)
1168 {
1169     /* we don't use async packets, so this should never be called */
1170     fprintf(stderr, "%s\n", __func__);
1171 }
1172 
1173 static void usb_mtp_handle_data(USBDevice *dev, USBPacket *p)
1174 {
1175     MTPState *s = USB_MTP(dev);
1176     MTPControl cmd;
1177     mtp_container container;
1178     uint32_t params[5];
1179     int i, rc;
1180 
1181     switch (p->ep->nr) {
1182     case EP_DATA_IN:
1183         if (s->data_out != NULL) {
1184             /* guest bug */
1185             trace_usb_mtp_stall(s->dev.addr, "awaiting data-out");
1186             p->status = USB_RET_STALL;
1187             return;
1188         }
1189         if (p->iov.size < sizeof(container)) {
1190             trace_usb_mtp_stall(s->dev.addr, "packet too small");
1191             p->status = USB_RET_STALL;
1192             return;
1193         }
1194         if (s->data_in !=  NULL) {
1195             MTPData *d = s->data_in;
1196             int dlen = d->length - d->offset;
1197             if (d->first) {
1198                 trace_usb_mtp_data_in(s->dev.addr, d->trans, d->length);
1199                 container.length = cpu_to_le32(d->length + sizeof(container));
1200                 container.type   = cpu_to_le16(TYPE_DATA);
1201                 container.code   = cpu_to_le16(d->code);
1202                 container.trans  = cpu_to_le32(d->trans);
1203                 usb_packet_copy(p, &container, sizeof(container));
1204                 d->first = false;
1205                 if (dlen > p->iov.size - sizeof(container)) {
1206                     dlen = p->iov.size - sizeof(container);
1207                 }
1208             } else {
1209                 if (dlen > p->iov.size) {
1210                     dlen = p->iov.size;
1211                 }
1212             }
1213             if (d->fd == -1) {
1214                 usb_packet_copy(p, d->data + d->offset, dlen);
1215             } else {
1216                 if (d->alloc < p->iov.size) {
1217                     d->alloc = p->iov.size;
1218                     d->data = g_realloc(d->data, d->alloc);
1219                 }
1220                 rc = read(d->fd, d->data, dlen);
1221                 if (rc != dlen) {
1222                     memset(d->data, 0, dlen);
1223                     s->result->code = RES_INCOMPLETE_TRANSFER;
1224                 }
1225                 usb_packet_copy(p, d->data, dlen);
1226             }
1227             d->offset += dlen;
1228             if (d->offset == d->length) {
1229                 usb_mtp_data_free(s->data_in);
1230                 s->data_in = NULL;
1231             }
1232         } else if (s->result != NULL) {
1233             MTPControl *r = s->result;
1234             int length = sizeof(container) + r->argc * sizeof(uint32_t);
1235             if (r->code == RES_OK) {
1236                 trace_usb_mtp_success(s->dev.addr, r->trans,
1237                                       (r->argc > 0) ? r->argv[0] : 0,
1238                                       (r->argc > 1) ? r->argv[1] : 0);
1239             } else {
1240                 trace_usb_mtp_error(s->dev.addr, r->code, r->trans,
1241                                     (r->argc > 0) ? r->argv[0] : 0,
1242                                     (r->argc > 1) ? r->argv[1] : 0);
1243             }
1244             container.length = cpu_to_le32(length);
1245             container.type   = cpu_to_le16(TYPE_RESPONSE);
1246             container.code   = cpu_to_le16(r->code);
1247             container.trans  = cpu_to_le32(r->trans);
1248             for (i = 0; i < r->argc; i++) {
1249                 params[i] = cpu_to_le32(r->argv[i]);
1250             }
1251             usb_packet_copy(p, &container, sizeof(container));
1252             usb_packet_copy(p, &params, length - sizeof(container));
1253             g_free(s->result);
1254             s->result = NULL;
1255         }
1256         break;
1257     case EP_DATA_OUT:
1258         if (p->iov.size < sizeof(container)) {
1259             trace_usb_mtp_stall(s->dev.addr, "packet too small");
1260             p->status = USB_RET_STALL;
1261             return;
1262         }
1263         usb_packet_copy(p, &container, sizeof(container));
1264         switch (le16_to_cpu(container.type)) {
1265         case TYPE_COMMAND:
1266             if (s->data_in || s->data_out || s->result) {
1267                 trace_usb_mtp_stall(s->dev.addr, "transaction inflight");
1268                 p->status = USB_RET_STALL;
1269                 return;
1270             }
1271             cmd.code = le16_to_cpu(container.code);
1272             cmd.argc = (le32_to_cpu(container.length) - sizeof(container))
1273                 / sizeof(uint32_t);
1274             cmd.trans = le32_to_cpu(container.trans);
1275             if (cmd.argc > ARRAY_SIZE(cmd.argv)) {
1276                 cmd.argc = ARRAY_SIZE(cmd.argv);
1277             }
1278             if (p->iov.size < sizeof(container) + cmd.argc * sizeof(uint32_t)) {
1279                 trace_usb_mtp_stall(s->dev.addr, "packet too small");
1280                 p->status = USB_RET_STALL;
1281                 return;
1282             }
1283             usb_packet_copy(p, &params, cmd.argc * sizeof(uint32_t));
1284             for (i = 0; i < cmd.argc; i++) {
1285                 cmd.argv[i] = le32_to_cpu(params[i]);
1286             }
1287             trace_usb_mtp_command(s->dev.addr, cmd.code, cmd.trans,
1288                                   (cmd.argc > 0) ? cmd.argv[0] : 0,
1289                                   (cmd.argc > 1) ? cmd.argv[1] : 0,
1290                                   (cmd.argc > 2) ? cmd.argv[2] : 0,
1291                                   (cmd.argc > 3) ? cmd.argv[3] : 0,
1292                                   (cmd.argc > 4) ? cmd.argv[4] : 0);
1293             usb_mtp_command(s, &cmd);
1294             break;
1295         default:
1296             /* not needed as long as the mtp device is read-only */
1297             p->status = USB_RET_STALL;
1298             return;
1299         }
1300         break;
1301     case EP_EVENT:
1302 #ifdef CONFIG_INOTIFY1
1303         if (!QTAILQ_EMPTY(&s->events)) {
1304             struct MTPMonEntry *e = QTAILQ_LAST(&s->events, events);
1305             uint32_t handle;
1306             int len = sizeof(container) + sizeof(uint32_t);
1307 
1308             if (p->iov.size < len) {
1309                 trace_usb_mtp_stall(s->dev.addr,
1310                                     "packet too small to send event");
1311                 p->status = USB_RET_STALL;
1312                 return;
1313             }
1314 
1315             QTAILQ_REMOVE(&s->events, e, next);
1316             container.length = cpu_to_le32(len);
1317             container.type = cpu_to_le32(TYPE_EVENT);
1318             container.code = cpu_to_le16(e->event);
1319             container.trans = 0; /* no trans specific events */
1320             handle = cpu_to_le32(e->handle);
1321             usb_packet_copy(p, &container, sizeof(container));
1322             usb_packet_copy(p, &handle, sizeof(uint32_t));
1323             g_free(e);
1324             return;
1325         }
1326 #endif
1327         p->status = USB_RET_NAK;
1328         return;
1329     default:
1330         trace_usb_mtp_stall(s->dev.addr, "invalid endpoint");
1331         p->status = USB_RET_STALL;
1332         return;
1333     }
1334 
1335     if (p->actual_length == 0) {
1336         trace_usb_mtp_nak(s->dev.addr, p->ep->nr);
1337         p->status = USB_RET_NAK;
1338         return;
1339     } else {
1340         trace_usb_mtp_xfer(s->dev.addr, p->ep->nr, p->actual_length,
1341                            p->iov.size);
1342         return;
1343     }
1344 }
1345 
1346 static void usb_mtp_realize(USBDevice *dev, Error **errp)
1347 {
1348     MTPState *s = USB_MTP(dev);
1349 
1350     usb_desc_create_serial(dev);
1351     usb_desc_init(dev);
1352     QTAILQ_INIT(&s->objects);
1353     if (s->desc == NULL) {
1354         if (s->root == NULL) {
1355             error_setg(errp, "usb-mtp: x-root property must be configured");
1356             return;
1357         }
1358         s->desc = strrchr(s->root, '/');
1359         if (s->desc && s->desc[0]) {
1360             s->desc = g_strdup(s->desc + 1);
1361         } else {
1362             s->desc = g_strdup("none");
1363         }
1364     }
1365 }
1366 
1367 static const VMStateDescription vmstate_usb_mtp = {
1368     .name = "usb-mtp",
1369     .unmigratable = 1,
1370     .version_id = 1,
1371     .minimum_version_id = 1,
1372     .fields = (VMStateField[]) {
1373         VMSTATE_USB_DEVICE(dev, MTPState),
1374         VMSTATE_END_OF_LIST()
1375     }
1376 };
1377 
1378 static Property mtp_properties[] = {
1379     DEFINE_PROP_STRING("x-root", MTPState, root),
1380     DEFINE_PROP_STRING("desc", MTPState, desc),
1381     DEFINE_PROP_END_OF_LIST(),
1382 };
1383 
1384 static void usb_mtp_class_initfn(ObjectClass *klass, void *data)
1385 {
1386     DeviceClass *dc = DEVICE_CLASS(klass);
1387     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
1388 
1389     uc->realize        = usb_mtp_realize;
1390     uc->product_desc   = "QEMU USB MTP";
1391     uc->usb_desc       = &desc;
1392     uc->cancel_packet  = usb_mtp_cancel_packet;
1393     uc->handle_attach  = usb_desc_attach;
1394     uc->handle_reset   = usb_mtp_handle_reset;
1395     uc->handle_control = usb_mtp_handle_control;
1396     uc->handle_data    = usb_mtp_handle_data;
1397     dc->fw_name = "mtp";
1398     dc->vmsd = &vmstate_usb_mtp;
1399     dc->props = mtp_properties;
1400 }
1401 
1402 static TypeInfo mtp_info = {
1403     .name          = TYPE_USB_MTP,
1404     .parent        = TYPE_USB_DEVICE,
1405     .instance_size = sizeof(MTPState),
1406     .class_init    = usb_mtp_class_initfn,
1407 };
1408 
1409 static void usb_mtp_register_types(void)
1410 {
1411     type_register_static(&mtp_info);
1412 }
1413 
1414 type_init(usb_mtp_register_types)
1415