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21#include <linux/blkdev.h>
22#include <linux/pagemap.h>
23#include <linux/export.h>
24#include <linux/hid.h>
25#include <asm/unaligned.h>
26
27#include <linux/usb/composite.h>
28#include <linux/usb/functionfs.h>
29
30
31#define FUNCTIONFS_MAGIC 0xa647361
32
33
34
35
36#ifdef VERBOSE_DEBUG
37#ifndef pr_vdebug
38# define pr_vdebug pr_debug
39#endif
40# define ffs_dump_mem(prefix, ptr, len) \
41 print_hex_dump_bytes(pr_fmt(prefix ": "), DUMP_PREFIX_NONE, ptr, len)
42#else
43#ifndef pr_vdebug
44# define pr_vdebug(...) do { } while (0)
45#endif
46# define ffs_dump_mem(prefix, ptr, len) do { } while (0)
47#endif
48
49#define ENTER() pr_vdebug("%s()\n", __func__)
50
51
52
53
54enum ffs_state {
55
56
57
58
59
60
61
62 FFS_READ_DESCRIPTORS,
63 FFS_READ_STRINGS,
64
65
66
67
68
69
70
71
72
73 FFS_ACTIVE,
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88 FFS_CLOSING
89};
90
91
92enum ffs_setup_state {
93
94 FFS_NO_SETUP,
95
96
97
98
99
100 FFS_SETUP_PENDING,
101
102
103
104
105
106
107 FFS_SETUP_CANCELED
108};
109
110
111
112struct ffs_epfile;
113struct ffs_function;
114
115struct ffs_data {
116 struct usb_gadget *gadget;
117
118
119
120
121
122
123
124 struct mutex mutex;
125
126
127
128
129
130
131 spinlock_t eps_lock;
132
133
134
135
136
137
138
139
140
141 struct usb_request *ep0req;
142 struct completion ep0req_completion;
143 int ep0req_status;
144
145
146 atomic_t ref;
147
148 atomic_t opened;
149
150
151 enum ffs_state state;
152
153
154
155
156
157
158
159
160
161
162 enum ffs_setup_state setup_state;
163
164#define FFS_SETUP_STATE(ffs) \
165 ((enum ffs_setup_state)cmpxchg(&(ffs)->setup_state, \
166 FFS_SETUP_CANCELED, FFS_NO_SETUP))
167
168
169 struct {
170 u8 types[4];
171 unsigned short count;
172
173 unsigned short can_stall;
174 struct usb_ctrlrequest setup;
175
176 wait_queue_head_t waitq;
177 } ev;
178
179
180 unsigned long flags;
181#define FFS_FL_CALL_CLOSED_CALLBACK 0
182#define FFS_FL_BOUND 1
183
184
185 struct ffs_function *func;
186
187
188
189
190
191 const char *dev_name;
192
193 void *private_data;
194
195
196
197
198
199
200
201
202 const void *raw_descs;
203 unsigned raw_descs_length;
204 unsigned raw_fs_descs_length;
205 unsigned fs_descs_count;
206 unsigned hs_descs_count;
207
208 unsigned short strings_count;
209 unsigned short interfaces_count;
210 unsigned short eps_count;
211 unsigned short _pad1;
212
213
214
215 const void *raw_strings;
216 struct usb_gadget_strings **stringtabs;
217
218
219
220
221
222 struct super_block *sb;
223
224
225 struct ffs_file_perms {
226 umode_t mode;
227 kuid_t uid;
228 kgid_t gid;
229 } file_perms;
230
231
232
233
234
235 struct ffs_epfile *epfiles;
236};
237
238
239static void ffs_data_get(struct ffs_data *ffs);
240static void ffs_data_put(struct ffs_data *ffs);
241
242static struct ffs_data *__must_check ffs_data_new(void) __attribute__((malloc));
243
244
245static void ffs_data_opened(struct ffs_data *ffs);
246static void ffs_data_closed(struct ffs_data *ffs);
247
248
249static int __must_check
250__ffs_data_got_descs(struct ffs_data *ffs, char *data, size_t len);
251static int __must_check
252__ffs_data_got_strings(struct ffs_data *ffs, char *data, size_t len);
253
254
255
256
257struct ffs_ep;
258
259struct ffs_function {
260 struct usb_configuration *conf;
261 struct usb_gadget *gadget;
262 struct ffs_data *ffs;
263
264 struct ffs_ep *eps;
265 u8 eps_revmap[16];
266 short *interfaces_nums;
267
268 struct usb_function function;
269};
270
271
272static struct ffs_function *ffs_func_from_usb(struct usb_function *f)
273{
274 return container_of(f, struct ffs_function, function);
275}
276
277static void ffs_func_free(struct ffs_function *func);
278
279static void ffs_func_eps_disable(struct ffs_function *func);
280static int __must_check ffs_func_eps_enable(struct ffs_function *func);
281
282static int ffs_func_bind(struct usb_configuration *,
283 struct usb_function *);
284static void ffs_func_unbind(struct usb_configuration *,
285 struct usb_function *);
286static int ffs_func_set_alt(struct usb_function *, unsigned, unsigned);
287static void ffs_func_disable(struct usb_function *);
288static int ffs_func_setup(struct usb_function *,
289 const struct usb_ctrlrequest *);
290static void ffs_func_suspend(struct usb_function *);
291static void ffs_func_resume(struct usb_function *);
292
293
294static int ffs_func_revmap_ep(struct ffs_function *func, u8 num);
295static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf);
296
297
298
299
300struct ffs_ep {
301 struct usb_ep *ep;
302 struct usb_request *req;
303
304
305 struct usb_endpoint_descriptor *descs[2];
306
307 u8 num;
308
309 int status;
310};
311
312struct ffs_epfile {
313
314 struct mutex mutex;
315 wait_queue_head_t wait;
316
317 struct ffs_data *ffs;
318 struct ffs_ep *ep;
319
320 struct dentry *dentry;
321
322 char name[5];
323
324 unsigned char in;
325 unsigned char isoc;
326
327 unsigned char _pad;
328};
329
330static int __must_check ffs_epfiles_create(struct ffs_data *ffs);
331static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count);
332
333static struct inode *__must_check
334ffs_sb_create_file(struct super_block *sb, const char *name, void *data,
335 const struct file_operations *fops,
336 struct dentry **dentry_p);
337
338
339
340
341static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
342 __attribute__((warn_unused_result, nonnull));
343static char *ffs_prepare_buffer(const char __user *buf, size_t len)
344 __attribute__((warn_unused_result, nonnull));
345
346
347
348
349static void ffs_ep0_complete(struct usb_ep *ep, struct usb_request *req)
350{
351 struct ffs_data *ffs = req->context;
352
353 complete_all(&ffs->ep0req_completion);
354}
355
356static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
357{
358 struct usb_request *req = ffs->ep0req;
359 int ret;
360
361 req->zero = len < le16_to_cpu(ffs->ev.setup.wLength);
362
363 spin_unlock_irq(&ffs->ev.waitq.lock);
364
365 req->buf = data;
366 req->length = len;
367
368
369
370
371
372
373 if (req->buf == NULL)
374 req->buf = (void *)0xDEADBABE;
375
376 INIT_COMPLETION(ffs->ep0req_completion);
377
378 ret = usb_ep_queue(ffs->gadget->ep0, req, GFP_ATOMIC);
379 if (unlikely(ret < 0))
380 return ret;
381
382 ret = wait_for_completion_interruptible(&ffs->ep0req_completion);
383 if (unlikely(ret)) {
384 usb_ep_dequeue(ffs->gadget->ep0, req);
385 return -EINTR;
386 }
387
388 ffs->setup_state = FFS_NO_SETUP;
389 return ffs->ep0req_status;
390}
391
392static int __ffs_ep0_stall(struct ffs_data *ffs)
393{
394 if (ffs->ev.can_stall) {
395 pr_vdebug("ep0 stall\n");
396 usb_ep_set_halt(ffs->gadget->ep0);
397 ffs->setup_state = FFS_NO_SETUP;
398 return -EL2HLT;
399 } else {
400 pr_debug("bogus ep0 stall!\n");
401 return -ESRCH;
402 }
403}
404
405static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
406 size_t len, loff_t *ptr)
407{
408 struct ffs_data *ffs = file->private_data;
409 ssize_t ret;
410 char *data;
411
412 ENTER();
413
414
415 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED)
416 return -EIDRM;
417
418
419 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
420 if (unlikely(ret < 0))
421 return ret;
422
423
424 switch (ffs->state) {
425 case FFS_READ_DESCRIPTORS:
426 case FFS_READ_STRINGS:
427
428 if (unlikely(len < 16)) {
429 ret = -EINVAL;
430 break;
431 }
432
433 data = ffs_prepare_buffer(buf, len);
434 if (IS_ERR(data)) {
435 ret = PTR_ERR(data);
436 break;
437 }
438
439
440 if (ffs->state == FFS_READ_DESCRIPTORS) {
441 pr_info("read descriptors\n");
442 ret = __ffs_data_got_descs(ffs, data, len);
443 if (unlikely(ret < 0))
444 break;
445
446 ffs->state = FFS_READ_STRINGS;
447 ret = len;
448 } else {
449 pr_info("read strings\n");
450 ret = __ffs_data_got_strings(ffs, data, len);
451 if (unlikely(ret < 0))
452 break;
453
454 ret = ffs_epfiles_create(ffs);
455 if (unlikely(ret)) {
456 ffs->state = FFS_CLOSING;
457 break;
458 }
459
460 ffs->state = FFS_ACTIVE;
461 mutex_unlock(&ffs->mutex);
462
463 ret = functionfs_ready_callback(ffs);
464 if (unlikely(ret < 0)) {
465 ffs->state = FFS_CLOSING;
466 return ret;
467 }
468
469 set_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags);
470 return len;
471 }
472 break;
473
474 case FFS_ACTIVE:
475 data = NULL;
476
477
478
479
480 spin_lock_irq(&ffs->ev.waitq.lock);
481 switch (FFS_SETUP_STATE(ffs)) {
482 case FFS_SETUP_CANCELED:
483 ret = -EIDRM;
484 goto done_spin;
485
486 case FFS_NO_SETUP:
487 ret = -ESRCH;
488 goto done_spin;
489
490 case FFS_SETUP_PENDING:
491 break;
492 }
493
494
495 if (!(ffs->ev.setup.bRequestType & USB_DIR_IN)) {
496 spin_unlock_irq(&ffs->ev.waitq.lock);
497 ret = __ffs_ep0_stall(ffs);
498 break;
499 }
500
501
502 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
503
504 spin_unlock_irq(&ffs->ev.waitq.lock);
505
506 data = ffs_prepare_buffer(buf, len);
507 if (IS_ERR(data)) {
508 ret = PTR_ERR(data);
509 break;
510 }
511
512 spin_lock_irq(&ffs->ev.waitq.lock);
513
514
515
516
517
518
519
520
521
522
523
524
525
526 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED) {
527 ret = -EIDRM;
528done_spin:
529 spin_unlock_irq(&ffs->ev.waitq.lock);
530 } else {
531
532 ret = __ffs_ep0_queue_wait(ffs, data, len);
533 }
534 kfree(data);
535 break;
536
537 default:
538 ret = -EBADFD;
539 break;
540 }
541
542 mutex_unlock(&ffs->mutex);
543 return ret;
544}
545
546static ssize_t __ffs_ep0_read_events(struct ffs_data *ffs, char __user *buf,
547 size_t n)
548{
549
550
551
552
553 struct usb_functionfs_event events[n];
554 unsigned i = 0;
555
556 memset(events, 0, sizeof events);
557
558 do {
559 events[i].type = ffs->ev.types[i];
560 if (events[i].type == FUNCTIONFS_SETUP) {
561 events[i].u.setup = ffs->ev.setup;
562 ffs->setup_state = FFS_SETUP_PENDING;
563 }
564 } while (++i < n);
565
566 if (n < ffs->ev.count) {
567 ffs->ev.count -= n;
568 memmove(ffs->ev.types, ffs->ev.types + n,
569 ffs->ev.count * sizeof *ffs->ev.types);
570 } else {
571 ffs->ev.count = 0;
572 }
573
574 spin_unlock_irq(&ffs->ev.waitq.lock);
575 mutex_unlock(&ffs->mutex);
576
577 return unlikely(__copy_to_user(buf, events, sizeof events))
578 ? -EFAULT : sizeof events;
579}
580
581static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
582 size_t len, loff_t *ptr)
583{
584 struct ffs_data *ffs = file->private_data;
585 char *data = NULL;
586 size_t n;
587 int ret;
588
589 ENTER();
590
591
592 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED)
593 return -EIDRM;
594
595
596 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
597 if (unlikely(ret < 0))
598 return ret;
599
600
601 if (ffs->state != FFS_ACTIVE) {
602 ret = -EBADFD;
603 goto done_mutex;
604 }
605
606
607
608
609
610 spin_lock_irq(&ffs->ev.waitq.lock);
611
612 switch (FFS_SETUP_STATE(ffs)) {
613 case FFS_SETUP_CANCELED:
614 ret = -EIDRM;
615 break;
616
617 case FFS_NO_SETUP:
618 n = len / sizeof(struct usb_functionfs_event);
619 if (unlikely(!n)) {
620 ret = -EINVAL;
621 break;
622 }
623
624 if ((file->f_flags & O_NONBLOCK) && !ffs->ev.count) {
625 ret = -EAGAIN;
626 break;
627 }
628
629 if (wait_event_interruptible_exclusive_locked_irq(ffs->ev.waitq,
630 ffs->ev.count)) {
631 ret = -EINTR;
632 break;
633 }
634
635 return __ffs_ep0_read_events(ffs, buf,
636 min(n, (size_t)ffs->ev.count));
637
638 case FFS_SETUP_PENDING:
639 if (ffs->ev.setup.bRequestType & USB_DIR_IN) {
640 spin_unlock_irq(&ffs->ev.waitq.lock);
641 ret = __ffs_ep0_stall(ffs);
642 goto done_mutex;
643 }
644
645 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
646
647 spin_unlock_irq(&ffs->ev.waitq.lock);
648
649 if (likely(len)) {
650 data = kmalloc(len, GFP_KERNEL);
651 if (unlikely(!data)) {
652 ret = -ENOMEM;
653 goto done_mutex;
654 }
655 }
656
657 spin_lock_irq(&ffs->ev.waitq.lock);
658
659
660 if (FFS_SETUP_STATE(ffs) == FFS_SETUP_CANCELED) {
661 ret = -EIDRM;
662 break;
663 }
664
665
666 ret = __ffs_ep0_queue_wait(ffs, data, len);
667 if (likely(ret > 0) && unlikely(__copy_to_user(buf, data, len)))
668 ret = -EFAULT;
669 goto done_mutex;
670
671 default:
672 ret = -EBADFD;
673 break;
674 }
675
676 spin_unlock_irq(&ffs->ev.waitq.lock);
677done_mutex:
678 mutex_unlock(&ffs->mutex);
679 kfree(data);
680 return ret;
681}
682
683static int ffs_ep0_open(struct inode *inode, struct file *file)
684{
685 struct ffs_data *ffs = inode->i_private;
686
687 ENTER();
688
689 if (unlikely(ffs->state == FFS_CLOSING))
690 return -EBUSY;
691
692 file->private_data = ffs;
693 ffs_data_opened(ffs);
694
695 return 0;
696}
697
698static int ffs_ep0_release(struct inode *inode, struct file *file)
699{
700 struct ffs_data *ffs = file->private_data;
701
702 ENTER();
703
704 ffs_data_closed(ffs);
705
706 return 0;
707}
708
709static long ffs_ep0_ioctl(struct file *file, unsigned code, unsigned long value)
710{
711 struct ffs_data *ffs = file->private_data;
712 struct usb_gadget *gadget = ffs->gadget;
713 long ret;
714
715 ENTER();
716
717 if (code == FUNCTIONFS_INTERFACE_REVMAP) {
718 struct ffs_function *func = ffs->func;
719 ret = func ? ffs_func_revmap_intf(func, value) : -ENODEV;
720 } else if (gadget && gadget->ops->ioctl) {
721 ret = gadget->ops->ioctl(gadget, code, value);
722 } else {
723 ret = -ENOTTY;
724 }
725
726 return ret;
727}
728
729static const struct file_operations ffs_ep0_operations = {
730 .owner = THIS_MODULE,
731 .llseek = no_llseek,
732
733 .open = ffs_ep0_open,
734 .write = ffs_ep0_write,
735 .read = ffs_ep0_read,
736 .release = ffs_ep0_release,
737 .unlocked_ioctl = ffs_ep0_ioctl,
738};
739
740
741
742
743static void ffs_epfile_io_complete(struct usb_ep *_ep, struct usb_request *req)
744{
745 ENTER();
746 if (likely(req->context)) {
747 struct ffs_ep *ep = _ep->driver_data;
748 ep->status = req->status ? req->status : req->actual;
749 complete(req->context);
750 }
751}
752
753static ssize_t ffs_epfile_io(struct file *file,
754 char __user *buf, size_t len, int read)
755{
756 struct ffs_epfile *epfile = file->private_data;
757 struct ffs_ep *ep;
758 char *data = NULL;
759 ssize_t ret;
760 int halt;
761
762 goto first_try;
763 do {
764 spin_unlock_irq(&epfile->ffs->eps_lock);
765 mutex_unlock(&epfile->mutex);
766
767first_try:
768
769 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE)) {
770 ret = -ENODEV;
771 goto error;
772 }
773
774
775 ep = epfile->ep;
776 if (!ep) {
777 if (file->f_flags & O_NONBLOCK) {
778 ret = -EAGAIN;
779 goto error;
780 }
781
782 if (wait_event_interruptible(epfile->wait,
783 (ep = epfile->ep))) {
784 ret = -EINTR;
785 goto error;
786 }
787 }
788
789
790 halt = !read == !epfile->in;
791 if (halt && epfile->isoc) {
792 ret = -EINVAL;
793 goto error;
794 }
795
796
797 if (!halt && !data) {
798 data = kzalloc(len, GFP_KERNEL);
799 if (unlikely(!data))
800 return -ENOMEM;
801
802 if (!read &&
803 unlikely(__copy_from_user(data, buf, len))) {
804 ret = -EFAULT;
805 goto error;
806 }
807 }
808
809
810 ret = ffs_mutex_lock(&epfile->mutex,
811 file->f_flags & O_NONBLOCK);
812 if (unlikely(ret))
813 goto error;
814
815
816
817
818
819 spin_lock_irq(&epfile->ffs->eps_lock);
820
821
822
823
824
825 } while (unlikely(epfile->ep != ep));
826
827
828 if (unlikely(halt)) {
829 if (likely(epfile->ep == ep) && !WARN_ON(!ep->ep))
830 usb_ep_set_halt(ep->ep);
831 spin_unlock_irq(&epfile->ffs->eps_lock);
832 ret = -EBADMSG;
833 } else {
834
835 DECLARE_COMPLETION_ONSTACK(done);
836
837 struct usb_request *req = ep->req;
838 req->context = &done;
839 req->complete = ffs_epfile_io_complete;
840 req->buf = data;
841 req->length = len;
842
843 ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
844
845 spin_unlock_irq(&epfile->ffs->eps_lock);
846
847 if (unlikely(ret < 0)) {
848
849 } else if (unlikely(wait_for_completion_interruptible(&done))) {
850 ret = -EINTR;
851 usb_ep_dequeue(ep->ep, req);
852 } else {
853 ret = ep->status;
854 if (read && ret > 0 &&
855 unlikely(copy_to_user(buf, data, ret)))
856 ret = -EFAULT;
857 }
858 }
859
860 mutex_unlock(&epfile->mutex);
861error:
862 kfree(data);
863 return ret;
864}
865
866static ssize_t
867ffs_epfile_write(struct file *file, const char __user *buf, size_t len,
868 loff_t *ptr)
869{
870 ENTER();
871
872 return ffs_epfile_io(file, (char __user *)buf, len, 0);
873}
874
875static ssize_t
876ffs_epfile_read(struct file *file, char __user *buf, size_t len, loff_t *ptr)
877{
878 ENTER();
879
880 return ffs_epfile_io(file, buf, len, 1);
881}
882
883static int
884ffs_epfile_open(struct inode *inode, struct file *file)
885{
886 struct ffs_epfile *epfile = inode->i_private;
887
888 ENTER();
889
890 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
891 return -ENODEV;
892
893 file->private_data = epfile;
894 ffs_data_opened(epfile->ffs);
895
896 return 0;
897}
898
899static int
900ffs_epfile_release(struct inode *inode, struct file *file)
901{
902 struct ffs_epfile *epfile = inode->i_private;
903
904 ENTER();
905
906 ffs_data_closed(epfile->ffs);
907
908 return 0;
909}
910
911static long ffs_epfile_ioctl(struct file *file, unsigned code,
912 unsigned long value)
913{
914 struct ffs_epfile *epfile = file->private_data;
915 int ret;
916
917 ENTER();
918
919 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
920 return -ENODEV;
921
922 spin_lock_irq(&epfile->ffs->eps_lock);
923 if (likely(epfile->ep)) {
924 switch (code) {
925 case FUNCTIONFS_FIFO_STATUS:
926 ret = usb_ep_fifo_status(epfile->ep->ep);
927 break;
928 case FUNCTIONFS_FIFO_FLUSH:
929 usb_ep_fifo_flush(epfile->ep->ep);
930 ret = 0;
931 break;
932 case FUNCTIONFS_CLEAR_HALT:
933 ret = usb_ep_clear_halt(epfile->ep->ep);
934 break;
935 case FUNCTIONFS_ENDPOINT_REVMAP:
936 ret = epfile->ep->num;
937 break;
938 default:
939 ret = -ENOTTY;
940 }
941 } else {
942 ret = -ENODEV;
943 }
944 spin_unlock_irq(&epfile->ffs->eps_lock);
945
946 return ret;
947}
948
949static const struct file_operations ffs_epfile_operations = {
950 .owner = THIS_MODULE,
951 .llseek = no_llseek,
952
953 .open = ffs_epfile_open,
954 .write = ffs_epfile_write,
955 .read = ffs_epfile_read,
956 .release = ffs_epfile_release,
957 .unlocked_ioctl = ffs_epfile_ioctl,
958};
959
960
961
962
963
964
965
966
967
968static struct inode *__must_check
969ffs_sb_make_inode(struct super_block *sb, void *data,
970 const struct file_operations *fops,
971 const struct inode_operations *iops,
972 struct ffs_file_perms *perms)
973{
974 struct inode *inode;
975
976 ENTER();
977
978 inode = new_inode(sb);
979
980 if (likely(inode)) {
981 struct timespec current_time = CURRENT_TIME;
982
983 inode->i_ino = get_next_ino();
984 inode->i_mode = perms->mode;
985 inode->i_uid = perms->uid;
986 inode->i_gid = perms->gid;
987 inode->i_atime = current_time;
988 inode->i_mtime = current_time;
989 inode->i_ctime = current_time;
990 inode->i_private = data;
991 if (fops)
992 inode->i_fop = fops;
993 if (iops)
994 inode->i_op = iops;
995 }
996
997 return inode;
998}
999
1000
1001static struct inode *ffs_sb_create_file(struct super_block *sb,
1002 const char *name, void *data,
1003 const struct file_operations *fops,
1004 struct dentry **dentry_p)
1005{
1006 struct ffs_data *ffs = sb->s_fs_info;
1007 struct dentry *dentry;
1008 struct inode *inode;
1009
1010 ENTER();
1011
1012 dentry = d_alloc_name(sb->s_root, name);
1013 if (unlikely(!dentry))
1014 return NULL;
1015
1016 inode = ffs_sb_make_inode(sb, data, fops, NULL, &ffs->file_perms);
1017 if (unlikely(!inode)) {
1018 dput(dentry);
1019 return NULL;
1020 }
1021
1022 d_add(dentry, inode);
1023 if (dentry_p)
1024 *dentry_p = dentry;
1025
1026 return inode;
1027}
1028
1029
1030static const struct super_operations ffs_sb_operations = {
1031 .statfs = simple_statfs,
1032 .drop_inode = generic_delete_inode,
1033};
1034
1035struct ffs_sb_fill_data {
1036 struct ffs_file_perms perms;
1037 umode_t root_mode;
1038 const char *dev_name;
1039 union {
1040
1041 void *private_data;
1042
1043 struct ffs_data *ffs_data;
1044 };
1045};
1046
1047static int ffs_sb_fill(struct super_block *sb, void *_data, int silent)
1048{
1049 struct ffs_sb_fill_data *data = _data;
1050 struct inode *inode;
1051 struct ffs_data *ffs;
1052
1053 ENTER();
1054
1055
1056 ffs = ffs_data_new();
1057 if (unlikely(!ffs))
1058 goto Enomem;
1059
1060 ffs->sb = sb;
1061 ffs->dev_name = kstrdup(data->dev_name, GFP_KERNEL);
1062 if (unlikely(!ffs->dev_name))
1063 goto Enomem;
1064 ffs->file_perms = data->perms;
1065 ffs->private_data = data->private_data;
1066
1067
1068 data->ffs_data = ffs;
1069
1070 sb->s_fs_info = ffs;
1071 sb->s_blocksize = PAGE_CACHE_SIZE;
1072 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
1073 sb->s_magic = FUNCTIONFS_MAGIC;
1074 sb->s_op = &ffs_sb_operations;
1075 sb->s_time_gran = 1;
1076
1077
1078 data->perms.mode = data->root_mode;
1079 inode = ffs_sb_make_inode(sb, NULL,
1080 &simple_dir_operations,
1081 &simple_dir_inode_operations,
1082 &data->perms);
1083 sb->s_root = d_make_root(inode);
1084 if (unlikely(!sb->s_root))
1085 goto Enomem;
1086
1087
1088 if (unlikely(!ffs_sb_create_file(sb, "ep0", ffs,
1089 &ffs_ep0_operations, NULL)))
1090 goto Enomem;
1091
1092 return 0;
1093
1094Enomem:
1095 return -ENOMEM;
1096}
1097
1098static int ffs_fs_parse_opts(struct ffs_sb_fill_data *data, char *opts)
1099{
1100 ENTER();
1101
1102 if (!opts || !*opts)
1103 return 0;
1104
1105 for (;;) {
1106 char *end, *eq, *comma;
1107 unsigned long value;
1108
1109
1110 comma = strchr(opts, ',');
1111 if (comma)
1112 *comma = 0;
1113
1114
1115 eq = strchr(opts, '=');
1116 if (unlikely(!eq)) {
1117 pr_err("'=' missing in %s\n", opts);
1118 return -EINVAL;
1119 }
1120 *eq = 0;
1121
1122
1123 value = simple_strtoul(eq + 1, &end, 0);
1124 if (unlikely(*end != ',' && *end != 0)) {
1125 pr_err("%s: invalid value: %s\n", opts, eq + 1);
1126 return -EINVAL;
1127 }
1128
1129
1130 switch (eq - opts) {
1131 case 5:
1132 if (!memcmp(opts, "rmode", 5))
1133 data->root_mode = (value & 0555) | S_IFDIR;
1134 else if (!memcmp(opts, "fmode", 5))
1135 data->perms.mode = (value & 0666) | S_IFREG;
1136 else
1137 goto invalid;
1138 break;
1139
1140 case 4:
1141 if (!memcmp(opts, "mode", 4)) {
1142 data->root_mode = (value & 0555) | S_IFDIR;
1143 data->perms.mode = (value & 0666) | S_IFREG;
1144 } else {
1145 goto invalid;
1146 }
1147 break;
1148
1149 case 3:
1150 if (!memcmp(opts, "uid", 3)) {
1151 data->perms.uid = make_kuid(current_user_ns(), value);
1152 if (!uid_valid(data->perms.uid)) {
1153 pr_err("%s: unmapped value: %lu\n", opts, value);
1154 return -EINVAL;
1155 }
1156 }
1157 else if (!memcmp(opts, "gid", 3))
1158 data->perms.gid = make_kgid(current_user_ns(), value);
1159 if (!gid_valid(data->perms.gid)) {
1160 pr_err("%s: unmapped value: %lu\n", opts, value);
1161 return -EINVAL;
1162 }
1163 else
1164 goto invalid;
1165 break;
1166
1167 default:
1168invalid:
1169 pr_err("%s: invalid option\n", opts);
1170 return -EINVAL;
1171 }
1172
1173
1174 if (!comma)
1175 break;
1176 opts = comma + 1;
1177 }
1178
1179 return 0;
1180}
1181
1182
1183
1184static struct dentry *
1185ffs_fs_mount(struct file_system_type *t, int flags,
1186 const char *dev_name, void *opts)
1187{
1188 struct ffs_sb_fill_data data = {
1189 .perms = {
1190 .mode = S_IFREG | 0600,
1191 .uid = GLOBAL_ROOT_UID,
1192 .gid = GLOBAL_ROOT_GID,
1193 },
1194 .root_mode = S_IFDIR | 0500,
1195 };
1196 struct dentry *rv;
1197 int ret;
1198 void *ffs_dev;
1199
1200 ENTER();
1201
1202 ret = ffs_fs_parse_opts(&data, opts);
1203 if (unlikely(ret < 0))
1204 return ERR_PTR(ret);
1205
1206 ffs_dev = functionfs_acquire_dev_callback(dev_name);
1207 if (IS_ERR(ffs_dev))
1208 return ffs_dev;
1209
1210 data.dev_name = dev_name;
1211 data.private_data = ffs_dev;
1212 rv = mount_nodev(t, flags, &data, ffs_sb_fill);
1213
1214
1215 if (IS_ERR(rv))
1216 functionfs_release_dev_callback(data.ffs_data);
1217
1218 return rv;
1219}
1220
1221static void
1222ffs_fs_kill_sb(struct super_block *sb)
1223{
1224 ENTER();
1225
1226 kill_litter_super(sb);
1227 if (sb->s_fs_info) {
1228 functionfs_release_dev_callback(sb->s_fs_info);
1229 ffs_data_put(sb->s_fs_info);
1230 }
1231}
1232
1233static struct file_system_type ffs_fs_type = {
1234 .owner = THIS_MODULE,
1235 .name = "functionfs",
1236 .mount = ffs_fs_mount,
1237 .kill_sb = ffs_fs_kill_sb,
1238};
1239
1240
1241
1242
1243static int functionfs_init(void)
1244{
1245 int ret;
1246
1247 ENTER();
1248
1249 ret = register_filesystem(&ffs_fs_type);
1250 if (likely(!ret))
1251 pr_info("file system registered\n");
1252 else
1253 pr_err("failed registering file system (%d)\n", ret);
1254
1255 return ret;
1256}
1257
1258static void functionfs_cleanup(void)
1259{
1260 ENTER();
1261
1262 pr_info("unloading\n");
1263 unregister_filesystem(&ffs_fs_type);
1264}
1265
1266
1267
1268
1269static void ffs_data_clear(struct ffs_data *ffs);
1270static void ffs_data_reset(struct ffs_data *ffs);
1271
1272static void ffs_data_get(struct ffs_data *ffs)
1273{
1274 ENTER();
1275
1276 atomic_inc(&ffs->ref);
1277}
1278
1279static void ffs_data_opened(struct ffs_data *ffs)
1280{
1281 ENTER();
1282
1283 atomic_inc(&ffs->ref);
1284 atomic_inc(&ffs->opened);
1285}
1286
1287static void ffs_data_put(struct ffs_data *ffs)
1288{
1289 ENTER();
1290
1291 if (unlikely(atomic_dec_and_test(&ffs->ref))) {
1292 pr_info("%s(): freeing\n", __func__);
1293 ffs_data_clear(ffs);
1294 BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
1295 waitqueue_active(&ffs->ep0req_completion.wait));
1296 kfree(ffs->dev_name);
1297 kfree(ffs);
1298 }
1299}
1300
1301static void ffs_data_closed(struct ffs_data *ffs)
1302{
1303 ENTER();
1304
1305 if (atomic_dec_and_test(&ffs->opened)) {
1306 ffs->state = FFS_CLOSING;
1307 ffs_data_reset(ffs);
1308 }
1309
1310 ffs_data_put(ffs);
1311}
1312
1313static struct ffs_data *ffs_data_new(void)
1314{
1315 struct ffs_data *ffs = kzalloc(sizeof *ffs, GFP_KERNEL);
1316 if (unlikely(!ffs))
1317 return 0;
1318
1319 ENTER();
1320
1321 atomic_set(&ffs->ref, 1);
1322 atomic_set(&ffs->opened, 0);
1323 ffs->state = FFS_READ_DESCRIPTORS;
1324 mutex_init(&ffs->mutex);
1325 spin_lock_init(&ffs->eps_lock);
1326 init_waitqueue_head(&ffs->ev.waitq);
1327 init_completion(&ffs->ep0req_completion);
1328
1329
1330 ffs->ev.can_stall = 1;
1331
1332 return ffs;
1333}
1334
1335static void ffs_data_clear(struct ffs_data *ffs)
1336{
1337 ENTER();
1338
1339 if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags))
1340 functionfs_closed_callback(ffs);
1341
1342 BUG_ON(ffs->gadget);
1343
1344 if (ffs->epfiles)
1345 ffs_epfiles_destroy(ffs->epfiles, ffs->eps_count);
1346
1347 kfree(ffs->raw_descs);
1348 kfree(ffs->raw_strings);
1349 kfree(ffs->stringtabs);
1350}
1351
1352static void ffs_data_reset(struct ffs_data *ffs)
1353{
1354 ENTER();
1355
1356 ffs_data_clear(ffs);
1357
1358 ffs->epfiles = NULL;
1359 ffs->raw_descs = NULL;
1360 ffs->raw_strings = NULL;
1361 ffs->stringtabs = NULL;
1362
1363 ffs->raw_descs_length = 0;
1364 ffs->raw_fs_descs_length = 0;
1365 ffs->fs_descs_count = 0;
1366 ffs->hs_descs_count = 0;
1367
1368 ffs->strings_count = 0;
1369 ffs->interfaces_count = 0;
1370 ffs->eps_count = 0;
1371
1372 ffs->ev.count = 0;
1373
1374 ffs->state = FFS_READ_DESCRIPTORS;
1375 ffs->setup_state = FFS_NO_SETUP;
1376 ffs->flags = 0;
1377}
1378
1379
1380static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
1381{
1382 struct usb_gadget_strings **lang;
1383 int first_id;
1384
1385 ENTER();
1386
1387 if (WARN_ON(ffs->state != FFS_ACTIVE
1388 || test_and_set_bit(FFS_FL_BOUND, &ffs->flags)))
1389 return -EBADFD;
1390
1391 first_id = usb_string_ids_n(cdev, ffs->strings_count);
1392 if (unlikely(first_id < 0))
1393 return first_id;
1394
1395 ffs->ep0req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
1396 if (unlikely(!ffs->ep0req))
1397 return -ENOMEM;
1398 ffs->ep0req->complete = ffs_ep0_complete;
1399 ffs->ep0req->context = ffs;
1400
1401 lang = ffs->stringtabs;
1402 for (lang = ffs->stringtabs; *lang; ++lang) {
1403 struct usb_string *str = (*lang)->strings;
1404 int id = first_id;
1405 for (; str->s; ++id, ++str)
1406 str->id = id;
1407 }
1408
1409 ffs->gadget = cdev->gadget;
1410 ffs_data_get(ffs);
1411 return 0;
1412}
1413
1414static void functionfs_unbind(struct ffs_data *ffs)
1415{
1416 ENTER();
1417
1418 if (!WARN_ON(!ffs->gadget)) {
1419 usb_ep_free_request(ffs->gadget->ep0, ffs->ep0req);
1420 ffs->ep0req = NULL;
1421 ffs->gadget = NULL;
1422 ffs_data_put(ffs);
1423 clear_bit(FFS_FL_BOUND, &ffs->flags);
1424 }
1425}
1426
1427static int ffs_epfiles_create(struct ffs_data *ffs)
1428{
1429 struct ffs_epfile *epfile, *epfiles;
1430 unsigned i, count;
1431
1432 ENTER();
1433
1434 count = ffs->eps_count;
1435 epfiles = kcalloc(count, sizeof(*epfiles), GFP_KERNEL);
1436 if (!epfiles)
1437 return -ENOMEM;
1438
1439 epfile = epfiles;
1440 for (i = 1; i <= count; ++i, ++epfile) {
1441 epfile->ffs = ffs;
1442 mutex_init(&epfile->mutex);
1443 init_waitqueue_head(&epfile->wait);
1444 sprintf(epfiles->name, "ep%u", i);
1445 if (!unlikely(ffs_sb_create_file(ffs->sb, epfiles->name, epfile,
1446 &ffs_epfile_operations,
1447 &epfile->dentry))) {
1448 ffs_epfiles_destroy(epfiles, i - 1);
1449 return -ENOMEM;
1450 }
1451 }
1452
1453 ffs->epfiles = epfiles;
1454 return 0;
1455}
1456
1457static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count)
1458{
1459 struct ffs_epfile *epfile = epfiles;
1460
1461 ENTER();
1462
1463 for (; count; --count, ++epfile) {
1464 BUG_ON(mutex_is_locked(&epfile->mutex) ||
1465 waitqueue_active(&epfile->wait));
1466 if (epfile->dentry) {
1467 d_delete(epfile->dentry);
1468 dput(epfile->dentry);
1469 epfile->dentry = NULL;
1470 }
1471 }
1472
1473 kfree(epfiles);
1474}
1475
1476static int functionfs_bind_config(struct usb_composite_dev *cdev,
1477 struct usb_configuration *c,
1478 struct ffs_data *ffs)
1479{
1480 struct ffs_function *func;
1481 int ret;
1482
1483 ENTER();
1484
1485 func = kzalloc(sizeof *func, GFP_KERNEL);
1486 if (unlikely(!func))
1487 return -ENOMEM;
1488
1489 func->function.name = "Function FS Gadget";
1490 func->function.strings = ffs->stringtabs;
1491
1492 func->function.bind = ffs_func_bind;
1493 func->function.unbind = ffs_func_unbind;
1494 func->function.set_alt = ffs_func_set_alt;
1495 func->function.disable = ffs_func_disable;
1496 func->function.setup = ffs_func_setup;
1497 func->function.suspend = ffs_func_suspend;
1498 func->function.resume = ffs_func_resume;
1499
1500 func->conf = c;
1501 func->gadget = cdev->gadget;
1502 func->ffs = ffs;
1503 ffs_data_get(ffs);
1504
1505 ret = usb_add_function(c, &func->function);
1506 if (unlikely(ret))
1507 ffs_func_free(func);
1508
1509 return ret;
1510}
1511
1512static void ffs_func_free(struct ffs_function *func)
1513{
1514 struct ffs_ep *ep = func->eps;
1515 unsigned count = func->ffs->eps_count;
1516 unsigned long flags;
1517
1518 ENTER();
1519
1520
1521 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1522 do {
1523 if (ep->ep && ep->req)
1524 usb_ep_free_request(ep->ep, ep->req);
1525 ep->req = NULL;
1526 ++ep;
1527 } while (--count);
1528 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1529
1530 ffs_data_put(func->ffs);
1531
1532 kfree(func->eps);
1533
1534
1535
1536
1537
1538
1539 kfree(func);
1540}
1541
1542static void ffs_func_eps_disable(struct ffs_function *func)
1543{
1544 struct ffs_ep *ep = func->eps;
1545 struct ffs_epfile *epfile = func->ffs->epfiles;
1546 unsigned count = func->ffs->eps_count;
1547 unsigned long flags;
1548
1549 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1550 do {
1551
1552 if (likely(ep->ep))
1553 usb_ep_disable(ep->ep);
1554 epfile->ep = NULL;
1555
1556 ++ep;
1557 ++epfile;
1558 } while (--count);
1559 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1560}
1561
1562static int ffs_func_eps_enable(struct ffs_function *func)
1563{
1564 struct ffs_data *ffs = func->ffs;
1565 struct ffs_ep *ep = func->eps;
1566 struct ffs_epfile *epfile = ffs->epfiles;
1567 unsigned count = ffs->eps_count;
1568 unsigned long flags;
1569 int ret = 0;
1570
1571 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1572 do {
1573 struct usb_endpoint_descriptor *ds;
1574 ds = ep->descs[ep->descs[1] ? 1 : 0];
1575
1576 ep->ep->driver_data = ep;
1577 ep->ep->desc = ds;
1578 ret = usb_ep_enable(ep->ep);
1579 if (likely(!ret)) {
1580 epfile->ep = ep;
1581 epfile->in = usb_endpoint_dir_in(ds);
1582 epfile->isoc = usb_endpoint_xfer_isoc(ds);
1583 } else {
1584 break;
1585 }
1586
1587 wake_up(&epfile->wait);
1588
1589 ++ep;
1590 ++epfile;
1591 } while (--count);
1592 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1593
1594 return ret;
1595}
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607enum ffs_entity_type {
1608 FFS_DESCRIPTOR, FFS_INTERFACE, FFS_STRING, FFS_ENDPOINT
1609};
1610
1611typedef int (*ffs_entity_callback)(enum ffs_entity_type entity,
1612 u8 *valuep,
1613 struct usb_descriptor_header *desc,
1614 void *priv);
1615
1616static int __must_check ffs_do_desc(char *data, unsigned len,
1617 ffs_entity_callback entity, void *priv)
1618{
1619 struct usb_descriptor_header *_ds = (void *)data;
1620 u8 length;
1621 int ret;
1622
1623 ENTER();
1624
1625
1626 if (len < 2) {
1627 pr_vdebug("descriptor too short\n");
1628 return -EINVAL;
1629 }
1630
1631
1632 length = _ds->bLength;
1633 if (len < length) {
1634 pr_vdebug("descriptor longer then available data\n");
1635 return -EINVAL;
1636 }
1637
1638#define __entity_check_INTERFACE(val) 1
1639#define __entity_check_STRING(val) (val)
1640#define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
1641#define __entity(type, val) do { \
1642 pr_vdebug("entity " #type "(%02x)\n", (val)); \
1643 if (unlikely(!__entity_check_ ##type(val))) { \
1644 pr_vdebug("invalid entity's value\n"); \
1645 return -EINVAL; \
1646 } \
1647 ret = entity(FFS_ ##type, &val, _ds, priv); \
1648 if (unlikely(ret < 0)) { \
1649 pr_debug("entity " #type "(%02x); ret = %d\n", \
1650 (val), ret); \
1651 return ret; \
1652 } \
1653 } while (0)
1654
1655
1656 switch (_ds->bDescriptorType) {
1657 case USB_DT_DEVICE:
1658 case USB_DT_CONFIG:
1659 case USB_DT_STRING:
1660 case USB_DT_DEVICE_QUALIFIER:
1661
1662 pr_vdebug("descriptor reserved for gadget: %d\n",
1663 _ds->bDescriptorType);
1664 return -EINVAL;
1665
1666 case USB_DT_INTERFACE: {
1667 struct usb_interface_descriptor *ds = (void *)_ds;
1668 pr_vdebug("interface descriptor\n");
1669 if (length != sizeof *ds)
1670 goto inv_length;
1671
1672 __entity(INTERFACE, ds->bInterfaceNumber);
1673 if (ds->iInterface)
1674 __entity(STRING, ds->iInterface);
1675 }
1676 break;
1677
1678 case USB_DT_ENDPOINT: {
1679 struct usb_endpoint_descriptor *ds = (void *)_ds;
1680 pr_vdebug("endpoint descriptor\n");
1681 if (length != USB_DT_ENDPOINT_SIZE &&
1682 length != USB_DT_ENDPOINT_AUDIO_SIZE)
1683 goto inv_length;
1684 __entity(ENDPOINT, ds->bEndpointAddress);
1685 }
1686 break;
1687
1688 case HID_DT_HID:
1689 pr_vdebug("hid descriptor\n");
1690 if (length != sizeof(struct hid_descriptor))
1691 goto inv_length;
1692 break;
1693
1694 case USB_DT_OTG:
1695 if (length != sizeof(struct usb_otg_descriptor))
1696 goto inv_length;
1697 break;
1698
1699 case USB_DT_INTERFACE_ASSOCIATION: {
1700 struct usb_interface_assoc_descriptor *ds = (void *)_ds;
1701 pr_vdebug("interface association descriptor\n");
1702 if (length != sizeof *ds)
1703 goto inv_length;
1704 if (ds->iFunction)
1705 __entity(STRING, ds->iFunction);
1706 }
1707 break;
1708
1709 case USB_DT_OTHER_SPEED_CONFIG:
1710 case USB_DT_INTERFACE_POWER:
1711 case USB_DT_DEBUG:
1712 case USB_DT_SECURITY:
1713 case USB_DT_CS_RADIO_CONTROL:
1714
1715 pr_vdebug("unimplemented descriptor: %d\n", _ds->bDescriptorType);
1716 return -EINVAL;
1717
1718 default:
1719
1720 pr_vdebug("unknown descriptor: %d\n", _ds->bDescriptorType);
1721 return -EINVAL;
1722
1723inv_length:
1724 pr_vdebug("invalid length: %d (descriptor %d)\n",
1725 _ds->bLength, _ds->bDescriptorType);
1726 return -EINVAL;
1727 }
1728
1729#undef __entity
1730#undef __entity_check_DESCRIPTOR
1731#undef __entity_check_INTERFACE
1732#undef __entity_check_STRING
1733#undef __entity_check_ENDPOINT
1734
1735 return length;
1736}
1737
1738static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
1739 ffs_entity_callback entity, void *priv)
1740{
1741 const unsigned _len = len;
1742 unsigned long num = 0;
1743
1744 ENTER();
1745
1746 for (;;) {
1747 int ret;
1748
1749 if (num == count)
1750 data = NULL;
1751
1752
1753 ret = entity(FFS_DESCRIPTOR, (u8 *)num, (void *)data, priv);
1754 if (unlikely(ret < 0)) {
1755 pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
1756 num, ret);
1757 return ret;
1758 }
1759
1760 if (!data)
1761 return _len - len;
1762
1763 ret = ffs_do_desc(data, len, entity, priv);
1764 if (unlikely(ret < 0)) {
1765 pr_debug("%s returns %d\n", __func__, ret);
1766 return ret;
1767 }
1768
1769 len -= ret;
1770 data += ret;
1771 ++num;
1772 }
1773}
1774
1775static int __ffs_data_do_entity(enum ffs_entity_type type,
1776 u8 *valuep, struct usb_descriptor_header *desc,
1777 void *priv)
1778{
1779 struct ffs_data *ffs = priv;
1780
1781 ENTER();
1782
1783 switch (type) {
1784 case FFS_DESCRIPTOR:
1785 break;
1786
1787 case FFS_INTERFACE:
1788
1789
1790
1791
1792
1793 if (*valuep >= ffs->interfaces_count)
1794 ffs->interfaces_count = *valuep + 1;
1795 break;
1796
1797 case FFS_STRING:
1798
1799
1800
1801
1802 if (*valuep > ffs->strings_count)
1803 ffs->strings_count = *valuep;
1804 break;
1805
1806 case FFS_ENDPOINT:
1807
1808 if ((*valuep & USB_ENDPOINT_NUMBER_MASK) > ffs->eps_count)
1809 ffs->eps_count = (*valuep & USB_ENDPOINT_NUMBER_MASK);
1810 break;
1811 }
1812
1813 return 0;
1814}
1815
1816static int __ffs_data_got_descs(struct ffs_data *ffs,
1817 char *const _data, size_t len)
1818{
1819 unsigned fs_count, hs_count;
1820 int fs_len, ret = -EINVAL;
1821 char *data = _data;
1822
1823 ENTER();
1824
1825 if (unlikely(get_unaligned_le32(data) != FUNCTIONFS_DESCRIPTORS_MAGIC ||
1826 get_unaligned_le32(data + 4) != len))
1827 goto error;
1828 fs_count = get_unaligned_le32(data + 8);
1829 hs_count = get_unaligned_le32(data + 12);
1830
1831 if (!fs_count && !hs_count)
1832 goto einval;
1833
1834 data += 16;
1835 len -= 16;
1836
1837 if (likely(fs_count)) {
1838 fs_len = ffs_do_descs(fs_count, data, len,
1839 __ffs_data_do_entity, ffs);
1840 if (unlikely(fs_len < 0)) {
1841 ret = fs_len;
1842 goto error;
1843 }
1844
1845 data += fs_len;
1846 len -= fs_len;
1847 } else {
1848 fs_len = 0;
1849 }
1850
1851 if (likely(hs_count)) {
1852 ret = ffs_do_descs(hs_count, data, len,
1853 __ffs_data_do_entity, ffs);
1854 if (unlikely(ret < 0))
1855 goto error;
1856 } else {
1857 ret = 0;
1858 }
1859
1860 if (unlikely(len != ret))
1861 goto einval;
1862
1863 ffs->raw_fs_descs_length = fs_len;
1864 ffs->raw_descs_length = fs_len + ret;
1865 ffs->raw_descs = _data;
1866 ffs->fs_descs_count = fs_count;
1867 ffs->hs_descs_count = hs_count;
1868
1869 return 0;
1870
1871einval:
1872 ret = -EINVAL;
1873error:
1874 kfree(_data);
1875 return ret;
1876}
1877
1878static int __ffs_data_got_strings(struct ffs_data *ffs,
1879 char *const _data, size_t len)
1880{
1881 u32 str_count, needed_count, lang_count;
1882 struct usb_gadget_strings **stringtabs, *t;
1883 struct usb_string *strings, *s;
1884 const char *data = _data;
1885
1886 ENTER();
1887
1888 if (unlikely(get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
1889 get_unaligned_le32(data + 4) != len))
1890 goto error;
1891 str_count = get_unaligned_le32(data + 8);
1892 lang_count = get_unaligned_le32(data + 12);
1893
1894
1895 if (unlikely(!str_count != !lang_count))
1896 goto error;
1897
1898
1899 needed_count = ffs->strings_count;
1900 if (unlikely(str_count < needed_count))
1901 goto error;
1902
1903
1904
1905
1906
1907 if (!needed_count) {
1908 kfree(_data);
1909 return 0;
1910 }
1911
1912
1913 {
1914 struct {
1915 struct usb_gadget_strings *stringtabs[lang_count + 1];
1916 struct usb_gadget_strings stringtab[lang_count];
1917 struct usb_string strings[lang_count*(needed_count+1)];
1918 } *d;
1919 unsigned i = 0;
1920
1921 d = kmalloc(sizeof *d, GFP_KERNEL);
1922 if (unlikely(!d)) {
1923 kfree(_data);
1924 return -ENOMEM;
1925 }
1926
1927 stringtabs = d->stringtabs;
1928 t = d->stringtab;
1929 i = lang_count;
1930 do {
1931 *stringtabs++ = t++;
1932 } while (--i);
1933 *stringtabs = NULL;
1934
1935 stringtabs = d->stringtabs;
1936 t = d->stringtab;
1937 s = d->strings;
1938 strings = s;
1939 }
1940
1941
1942 data += 16;
1943 len -= 16;
1944
1945 do {
1946 unsigned needed = needed_count;
1947
1948 if (unlikely(len < 3))
1949 goto error_free;
1950 t->language = get_unaligned_le16(data);
1951 t->strings = s;
1952 ++t;
1953
1954 data += 2;
1955 len -= 2;
1956
1957
1958 do {
1959 size_t length = strnlen(data, len);
1960
1961 if (unlikely(length == len))
1962 goto error_free;
1963
1964
1965
1966
1967
1968
1969 if (likely(needed)) {
1970
1971
1972
1973
1974
1975 s->s = data;
1976 --needed;
1977 ++s;
1978 }
1979
1980 data += length + 1;
1981 len -= length + 1;
1982 } while (--str_count);
1983
1984 s->id = 0;
1985 s->s = NULL;
1986 ++s;
1987
1988 } while (--lang_count);
1989
1990
1991 if (unlikely(len))
1992 goto error_free;
1993
1994
1995 ffs->stringtabs = stringtabs;
1996 ffs->raw_strings = _data;
1997
1998 return 0;
1999
2000error_free:
2001 kfree(stringtabs);
2002error:
2003 kfree(_data);
2004 return -EINVAL;
2005}
2006
2007
2008
2009
2010static void __ffs_event_add(struct ffs_data *ffs,
2011 enum usb_functionfs_event_type type)
2012{
2013 enum usb_functionfs_event_type rem_type1, rem_type2 = type;
2014 int neg = 0;
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024 if (ffs->setup_state == FFS_SETUP_PENDING)
2025 ffs->setup_state = FFS_SETUP_CANCELED;
2026
2027 switch (type) {
2028 case FUNCTIONFS_RESUME:
2029 rem_type2 = FUNCTIONFS_SUSPEND;
2030
2031 case FUNCTIONFS_SUSPEND:
2032 case FUNCTIONFS_SETUP:
2033 rem_type1 = type;
2034
2035 break;
2036
2037 case FUNCTIONFS_BIND:
2038 case FUNCTIONFS_UNBIND:
2039 case FUNCTIONFS_DISABLE:
2040 case FUNCTIONFS_ENABLE:
2041
2042 rem_type1 = FUNCTIONFS_SUSPEND;
2043 rem_type2 = FUNCTIONFS_RESUME;
2044 neg = 1;
2045 break;
2046
2047 default:
2048 BUG();
2049 }
2050
2051 {
2052 u8 *ev = ffs->ev.types, *out = ev;
2053 unsigned n = ffs->ev.count;
2054 for (; n; --n, ++ev)
2055 if ((*ev == rem_type1 || *ev == rem_type2) == neg)
2056 *out++ = *ev;
2057 else
2058 pr_vdebug("purging event %d\n", *ev);
2059 ffs->ev.count = out - ffs->ev.types;
2060 }
2061
2062 pr_vdebug("adding event %d\n", type);
2063 ffs->ev.types[ffs->ev.count++] = type;
2064 wake_up_locked(&ffs->ev.waitq);
2065}
2066
2067static void ffs_event_add(struct ffs_data *ffs,
2068 enum usb_functionfs_event_type type)
2069{
2070 unsigned long flags;
2071 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2072 __ffs_event_add(ffs, type);
2073 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2074}
2075
2076
2077
2078
2079static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
2080 struct usb_descriptor_header *desc,
2081 void *priv)
2082{
2083 struct usb_endpoint_descriptor *ds = (void *)desc;
2084 struct ffs_function *func = priv;
2085 struct ffs_ep *ffs_ep;
2086
2087
2088
2089
2090
2091 const int isHS = func->function.hs_descriptors != NULL;
2092 unsigned idx;
2093
2094 if (type != FFS_DESCRIPTOR)
2095 return 0;
2096
2097 if (isHS)
2098 func->function.hs_descriptors[(long)valuep] = desc;
2099 else
2100 func->function.descriptors[(long)valuep] = desc;
2101
2102 if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT)
2103 return 0;
2104
2105 idx = (ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK) - 1;
2106 ffs_ep = func->eps + idx;
2107
2108 if (unlikely(ffs_ep->descs[isHS])) {
2109 pr_vdebug("two %sspeed descriptors for EP %d\n",
2110 isHS ? "high" : "full",
2111 ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2112 return -EINVAL;
2113 }
2114 ffs_ep->descs[isHS] = ds;
2115
2116 ffs_dump_mem(": Original ep desc", ds, ds->bLength);
2117 if (ffs_ep->ep) {
2118 ds->bEndpointAddress = ffs_ep->descs[0]->bEndpointAddress;
2119 if (!ds->wMaxPacketSize)
2120 ds->wMaxPacketSize = ffs_ep->descs[0]->wMaxPacketSize;
2121 } else {
2122 struct usb_request *req;
2123 struct usb_ep *ep;
2124
2125 pr_vdebug("autoconfig\n");
2126 ep = usb_ep_autoconfig(func->gadget, ds);
2127 if (unlikely(!ep))
2128 return -ENOTSUPP;
2129 ep->driver_data = func->eps + idx;
2130
2131 req = usb_ep_alloc_request(ep, GFP_KERNEL);
2132 if (unlikely(!req))
2133 return -ENOMEM;
2134
2135 ffs_ep->ep = ep;
2136 ffs_ep->req = req;
2137 func->eps_revmap[ds->bEndpointAddress &
2138 USB_ENDPOINT_NUMBER_MASK] = idx + 1;
2139 }
2140 ffs_dump_mem(": Rewritten ep desc", ds, ds->bLength);
2141
2142 return 0;
2143}
2144
2145static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
2146 struct usb_descriptor_header *desc,
2147 void *priv)
2148{
2149 struct ffs_function *func = priv;
2150 unsigned idx;
2151 u8 newValue;
2152
2153 switch (type) {
2154 default:
2155 case FFS_DESCRIPTOR:
2156
2157 return 0;
2158
2159 case FFS_INTERFACE:
2160 idx = *valuep;
2161 if (func->interfaces_nums[idx] < 0) {
2162 int id = usb_interface_id(func->conf, &func->function);
2163 if (unlikely(id < 0))
2164 return id;
2165 func->interfaces_nums[idx] = id;
2166 }
2167 newValue = func->interfaces_nums[idx];
2168 break;
2169
2170 case FFS_STRING:
2171
2172 newValue = func->ffs->stringtabs[0]->strings[*valuep - 1].id;
2173 break;
2174
2175 case FFS_ENDPOINT:
2176
2177
2178
2179
2180 if (desc->bDescriptorType == USB_DT_ENDPOINT)
2181 return 0;
2182
2183 idx = (*valuep & USB_ENDPOINT_NUMBER_MASK) - 1;
2184 if (unlikely(!func->eps[idx].ep))
2185 return -EINVAL;
2186
2187 {
2188 struct usb_endpoint_descriptor **descs;
2189 descs = func->eps[idx].descs;
2190 newValue = descs[descs[0] ? 0 : 1]->bEndpointAddress;
2191 }
2192 break;
2193 }
2194
2195 pr_vdebug("%02x -> %02x\n", *valuep, newValue);
2196 *valuep = newValue;
2197 return 0;
2198}
2199
2200static int ffs_func_bind(struct usb_configuration *c,
2201 struct usb_function *f)
2202{
2203 struct ffs_function *func = ffs_func_from_usb(f);
2204 struct ffs_data *ffs = func->ffs;
2205
2206 const int full = !!func->ffs->fs_descs_count;
2207 const int high = gadget_is_dualspeed(func->gadget) &&
2208 func->ffs->hs_descs_count;
2209
2210 int ret;
2211
2212
2213 struct {
2214 struct ffs_ep eps[ffs->eps_count];
2215 struct usb_descriptor_header
2216 *fs_descs[full ? ffs->fs_descs_count + 1 : 0];
2217 struct usb_descriptor_header
2218 *hs_descs[high ? ffs->hs_descs_count + 1 : 0];
2219 short inums[ffs->interfaces_count];
2220 char raw_descs[high ? ffs->raw_descs_length
2221 : ffs->raw_fs_descs_length];
2222 } *data;
2223
2224 ENTER();
2225
2226
2227 if (unlikely(!(full | high)))
2228 return -ENOTSUPP;
2229
2230
2231 data = kmalloc(sizeof *data, GFP_KERNEL);
2232 if (unlikely(!data))
2233 return -ENOMEM;
2234
2235
2236 memset(data->eps, 0, sizeof data->eps);
2237 memcpy(data->raw_descs, ffs->raw_descs + 16, sizeof data->raw_descs);
2238 memset(data->inums, 0xff, sizeof data->inums);
2239 for (ret = ffs->eps_count; ret; --ret)
2240 data->eps[ret].num = -1;
2241
2242
2243 func->eps = data->eps;
2244 func->interfaces_nums = data->inums;
2245
2246
2247
2248
2249
2250
2251 if (likely(full)) {
2252 func->function.descriptors = data->fs_descs;
2253 ret = ffs_do_descs(ffs->fs_descs_count,
2254 data->raw_descs,
2255 sizeof data->raw_descs,
2256 __ffs_func_bind_do_descs, func);
2257 if (unlikely(ret < 0))
2258 goto error;
2259 } else {
2260 ret = 0;
2261 }
2262
2263 if (likely(high)) {
2264 func->function.hs_descriptors = data->hs_descs;
2265 ret = ffs_do_descs(ffs->hs_descs_count,
2266 data->raw_descs + ret,
2267 (sizeof data->raw_descs) - ret,
2268 __ffs_func_bind_do_descs, func);
2269 }
2270
2271
2272
2273
2274
2275
2276 ret = ffs_do_descs(ffs->fs_descs_count +
2277 (high ? ffs->hs_descs_count : 0),
2278 data->raw_descs, sizeof data->raw_descs,
2279 __ffs_func_bind_do_nums, func);
2280 if (unlikely(ret < 0))
2281 goto error;
2282
2283
2284 ffs_event_add(ffs, FUNCTIONFS_BIND);
2285 return 0;
2286
2287error:
2288
2289 return ret;
2290}
2291
2292
2293
2294
2295static void ffs_func_unbind(struct usb_configuration *c,
2296 struct usb_function *f)
2297{
2298 struct ffs_function *func = ffs_func_from_usb(f);
2299 struct ffs_data *ffs = func->ffs;
2300
2301 ENTER();
2302
2303 if (ffs->func == func) {
2304 ffs_func_eps_disable(func);
2305 ffs->func = NULL;
2306 }
2307
2308 ffs_event_add(ffs, FUNCTIONFS_UNBIND);
2309
2310 ffs_func_free(func);
2311}
2312
2313static int ffs_func_set_alt(struct usb_function *f,
2314 unsigned interface, unsigned alt)
2315{
2316 struct ffs_function *func = ffs_func_from_usb(f);
2317 struct ffs_data *ffs = func->ffs;
2318 int ret = 0, intf;
2319
2320 if (alt != (unsigned)-1) {
2321 intf = ffs_func_revmap_intf(func, interface);
2322 if (unlikely(intf < 0))
2323 return intf;
2324 }
2325
2326 if (ffs->func)
2327 ffs_func_eps_disable(ffs->func);
2328
2329 if (ffs->state != FFS_ACTIVE)
2330 return -ENODEV;
2331
2332 if (alt == (unsigned)-1) {
2333 ffs->func = NULL;
2334 ffs_event_add(ffs, FUNCTIONFS_DISABLE);
2335 return 0;
2336 }
2337
2338 ffs->func = func;
2339 ret = ffs_func_eps_enable(func);
2340 if (likely(ret >= 0))
2341 ffs_event_add(ffs, FUNCTIONFS_ENABLE);
2342 return ret;
2343}
2344
2345static void ffs_func_disable(struct usb_function *f)
2346{
2347 ffs_func_set_alt(f, 0, (unsigned)-1);
2348}
2349
2350static int ffs_func_setup(struct usb_function *f,
2351 const struct usb_ctrlrequest *creq)
2352{
2353 struct ffs_function *func = ffs_func_from_usb(f);
2354 struct ffs_data *ffs = func->ffs;
2355 unsigned long flags;
2356 int ret;
2357
2358 ENTER();
2359
2360 pr_vdebug("creq->bRequestType = %02x\n", creq->bRequestType);
2361 pr_vdebug("creq->bRequest = %02x\n", creq->bRequest);
2362 pr_vdebug("creq->wValue = %04x\n", le16_to_cpu(creq->wValue));
2363 pr_vdebug("creq->wIndex = %04x\n", le16_to_cpu(creq->wIndex));
2364 pr_vdebug("creq->wLength = %04x\n", le16_to_cpu(creq->wLength));
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375 if (ffs->state != FFS_ACTIVE)
2376 return -ENODEV;
2377
2378 switch (creq->bRequestType & USB_RECIP_MASK) {
2379 case USB_RECIP_INTERFACE:
2380 ret = ffs_func_revmap_intf(func, le16_to_cpu(creq->wIndex));
2381 if (unlikely(ret < 0))
2382 return ret;
2383 break;
2384
2385 case USB_RECIP_ENDPOINT:
2386 ret = ffs_func_revmap_ep(func, le16_to_cpu(creq->wIndex));
2387 if (unlikely(ret < 0))
2388 return ret;
2389 break;
2390
2391 default:
2392 return -EOPNOTSUPP;
2393 }
2394
2395 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2396 ffs->ev.setup = *creq;
2397 ffs->ev.setup.wIndex = cpu_to_le16(ret);
2398 __ffs_event_add(ffs, FUNCTIONFS_SETUP);
2399 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2400
2401 return 0;
2402}
2403
2404static void ffs_func_suspend(struct usb_function *f)
2405{
2406 ENTER();
2407 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_SUSPEND);
2408}
2409
2410static void ffs_func_resume(struct usb_function *f)
2411{
2412 ENTER();
2413 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_RESUME);
2414}
2415
2416
2417
2418
2419static int ffs_func_revmap_ep(struct ffs_function *func, u8 num)
2420{
2421 num = func->eps_revmap[num & USB_ENDPOINT_NUMBER_MASK];
2422 return num ? num : -EDOM;
2423}
2424
2425static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf)
2426{
2427 short *nums = func->interfaces_nums;
2428 unsigned count = func->ffs->interfaces_count;
2429
2430 for (; count; --count, ++nums) {
2431 if (*nums >= 0 && *nums == intf)
2432 return nums - func->interfaces_nums;
2433 }
2434
2435 return -EDOM;
2436}
2437
2438
2439
2440
2441static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
2442{
2443 return nonblock
2444 ? likely(mutex_trylock(mutex)) ? 0 : -EAGAIN
2445 : mutex_lock_interruptible(mutex);
2446}
2447
2448static char *ffs_prepare_buffer(const char __user *buf, size_t len)
2449{
2450 char *data;
2451
2452 if (unlikely(!len))
2453 return NULL;
2454
2455 data = kmalloc(len, GFP_KERNEL);
2456 if (unlikely(!data))
2457 return ERR_PTR(-ENOMEM);
2458
2459 if (unlikely(__copy_from_user(data, buf, len))) {
2460 kfree(data);
2461 return ERR_PTR(-EFAULT);
2462 }
2463
2464 pr_vdebug("Buffer from user space:\n");
2465 ffs_dump_mem("", data, len);
2466
2467 return data;
2468}
2469