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bna: remove oper_state_cbfn from struct bna_rxf
[linux/fpc-iii.git] / drivers / usb / gadget / function / f_fs.c
blob3507f880eb74294c76ddbc43c3aa153528478f53
1 /*
2 * f_fs.c -- user mode file system API for USB composite function controllers
3 *
4 * Copyright (C) 2010 Samsung Electronics
5 * Author: Michal Nazarewicz <mina86@mina86.com>
6 *
7 * Based on inode.c (GadgetFS) which was:
8 * Copyright (C) 2003-2004 David Brownell
9 * Copyright (C) 2003 Agilent Technologies
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 */
16
17
18 /* #define DEBUG */
19 /* #define VERBOSE_DEBUG */
20
21 #include <linux/blkdev.h>
22 #include <linux/pagemap.h>
23 #include <linux/export.h>
24 #include <linux/hid.h>
25 #include <linux/module.h>
26 #include <linux/uio.h>
27 #include <asm/unaligned.h>
28
29 #include <linux/usb/composite.h>
30 #include <linux/usb/functionfs.h>
31
32 #include <linux/aio.h>
33 #include <linux/mmu_context.h>
34 #include <linux/poll.h>
35 #include <linux/eventfd.h>
36
37 #include "u_fs.h"
38 #include "u_f.h"
39 #include "u_os_desc.h"
40 #include "configfs.h"
41
42 #define FUNCTIONFS_MAGIC 0xa647361 /* Chosen by a honest dice roll ;) */
43
44 /* Reference counter handling */
45 static void ffs_data_get(struct ffs_data *ffs);
46 static void ffs_data_put(struct ffs_data *ffs);
47 /* Creates new ffs_data object. */
48 static struct ffs_data *__must_check ffs_data_new(void) __attribute__((malloc));
49
50 /* Opened counter handling. */
51 static void ffs_data_opened(struct ffs_data *ffs);
52 static void ffs_data_closed(struct ffs_data *ffs);
53
54 /* Called with ffs->mutex held; take over ownership of data. */
55 static int __must_check
56 __ffs_data_got_descs(struct ffs_data *ffs, char *data, size_t len);
57 static int __must_check
58 __ffs_data_got_strings(struct ffs_data *ffs, char *data, size_t len);
59
60
61 /* The function structure ***************************************************/
62
63 struct ffs_ep;
64
65 struct ffs_function {
66 struct usb_configuration *conf;
67 struct usb_gadget *gadget;
68 struct ffs_data *ffs;
69
70 struct ffs_ep *eps;
71 u8 eps_revmap[16];
72 short *interfaces_nums;
73
74 struct usb_function function;
75 };
76
77
78 static struct ffs_function *ffs_func_from_usb(struct usb_function *f)
79 {
80 return container_of(f, struct ffs_function, function);
81 }
82
83
84 static inline enum ffs_setup_state
85 ffs_setup_state_clear_cancelled(struct ffs_data *ffs)
86 {
87 return (enum ffs_setup_state)
88 cmpxchg(&ffs->setup_state, FFS_SETUP_CANCELLED, FFS_NO_SETUP);
89 }
90
91
92 static void ffs_func_eps_disable(struct ffs_function *func);
93 static int __must_check ffs_func_eps_enable(struct ffs_function *func);
94
95 static int ffs_func_bind(struct usb_configuration *,
96 struct usb_function *);
97 static int ffs_func_set_alt(struct usb_function *, unsigned, unsigned);
98 static void ffs_func_disable(struct usb_function *);
99 static int ffs_func_setup(struct usb_function *,
100 const struct usb_ctrlrequest *);
101 static void ffs_func_suspend(struct usb_function *);
102 static void ffs_func_resume(struct usb_function *);
103
104
105 static int ffs_func_revmap_ep(struct ffs_function *func, u8 num);
106 static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf);
107
108
109 /* The endpoints structures *************************************************/
110
111 struct ffs_ep {
112 struct usb_ep *ep; /* P: ffs->eps_lock */
113 struct usb_request *req; /* P: epfile->mutex */
114
115 /* [0]: full speed, [1]: high speed, [2]: super speed */
116 struct usb_endpoint_descriptor *descs[3];
117
118 u8 num;
119
120 int status; /* P: epfile->mutex */
121 };
122
123 struct ffs_epfile {
124 /* Protects ep->ep and ep->req. */
125 struct mutex mutex;
126 wait_queue_head_t wait;
127
128 struct ffs_data *ffs;
129 struct ffs_ep *ep; /* P: ffs->eps_lock */
130
131 struct dentry *dentry;
132
133 char name[5];
134
135 unsigned char in; /* P: ffs->eps_lock */
136 unsigned char isoc; /* P: ffs->eps_lock */
137
138 unsigned char _pad;
139 };
140
141 /* ffs_io_data structure ***************************************************/
142
143 struct ffs_io_data {
144 bool aio;
145 bool read;
146
147 struct kiocb *kiocb;
148 struct iov_iter data;
149 const void *to_free;
150 char *buf;
151
152 struct mm_struct *mm;
153 struct work_struct work;
154
155 struct usb_ep *ep;
156 struct usb_request *req;
157
158 struct ffs_data *ffs;
159 };
160
161 struct ffs_desc_helper {
162 struct ffs_data *ffs;
163 unsigned interfaces_count;
164 unsigned eps_count;
165 };
166
167 static int __must_check ffs_epfiles_create(struct ffs_data *ffs);
168 static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count);
169
170 static struct dentry *
171 ffs_sb_create_file(struct super_block *sb, const char *name, void *data,
172 const struct file_operations *fops);
173
174 /* Devices management *******************************************************/
175
176 DEFINE_MUTEX(ffs_lock);
177 EXPORT_SYMBOL_GPL(ffs_lock);
178
179 static struct ffs_dev *_ffs_find_dev(const char *name);
180 static struct ffs_dev *_ffs_alloc_dev(void);
181 static int _ffs_name_dev(struct ffs_dev *dev, const char *name);
182 static void _ffs_free_dev(struct ffs_dev *dev);
183 static void *ffs_acquire_dev(const char *dev_name);
184 static void ffs_release_dev(struct ffs_data *ffs_data);
185 static int ffs_ready(struct ffs_data *ffs);
186 static void ffs_closed(struct ffs_data *ffs);
187
188 /* Misc helper functions ****************************************************/
189
190 static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
191 __attribute__((warn_unused_result, nonnull));
192 static char *ffs_prepare_buffer(const char __user *buf, size_t len)
193 __attribute__((warn_unused_result, nonnull));
194
195
196 /* Control file aka ep0 *****************************************************/
197
198 static void ffs_ep0_complete(struct usb_ep *ep, struct usb_request *req)
199 {
200 struct ffs_data *ffs = req->context;
201
202 complete_all(&ffs->ep0req_completion);
203 }
204
205 static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
206 {
207 struct usb_request *req = ffs->ep0req;
208 int ret;
209
210 req->zero = len < le16_to_cpu(ffs->ev.setup.wLength);
211
212 spin_unlock_irq(&ffs->ev.waitq.lock);
213
214 req->buf = data;
215 req->length = len;
216
217 /*
218 * UDC layer requires to provide a buffer even for ZLP, but should
219 * not use it at all. Let's provide some poisoned pointer to catch
220 * possible bug in the driver.
221 */
222 if (req->buf == NULL)
223 req->buf = (void *)0xDEADBABE;
224
225 reinit_completion(&ffs->ep0req_completion);
226
227 ret = usb_ep_queue(ffs->gadget->ep0, req, GFP_ATOMIC);
228 if (unlikely(ret < 0))
229 return ret;
230
231 ret = wait_for_completion_interruptible(&ffs->ep0req_completion);
232 if (unlikely(ret)) {
233 usb_ep_dequeue(ffs->gadget->ep0, req);
234 return -EINTR;
235 }
236
237 ffs->setup_state = FFS_NO_SETUP;
238 return req->status ? req->status : req->actual;
239 }
240
241 static int __ffs_ep0_stall(struct ffs_data *ffs)
242 {
243 if (ffs->ev.can_stall) {
244 pr_vdebug("ep0 stall\n");
245 usb_ep_set_halt(ffs->gadget->ep0);
246 ffs->setup_state = FFS_NO_SETUP;
247 return -EL2HLT;
248 } else {
249 pr_debug("bogus ep0 stall!\n");
250 return -ESRCH;
251 }
252 }
253
254 static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
255 size_t len, loff_t *ptr)
256 {
257 struct ffs_data *ffs = file->private_data;
258 ssize_t ret;
259 char *data;
260
261 ENTER();
262
263 /* Fast check if setup was canceled */
264 if (ffs_setup_state_clear_cancelled(ffs) == FFS_SETUP_CANCELLED)
265 return -EIDRM;
266
267 /* Acquire mutex */
268 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
269 if (unlikely(ret < 0))
270 return ret;
271
272 /* Check state */
273 switch (ffs->state) {
274 case FFS_READ_DESCRIPTORS:
275 case FFS_READ_STRINGS:
276 /* Copy data */
277 if (unlikely(len < 16)) {
278 ret = -EINVAL;
279 break;
280 }
281
282 data = ffs_prepare_buffer(buf, len);
283 if (IS_ERR(data)) {
284 ret = PTR_ERR(data);
285 break;
286 }
287
288 /* Handle data */
289 if (ffs->state == FFS_READ_DESCRIPTORS) {
290 pr_info("read descriptors\n");
291 ret = __ffs_data_got_descs(ffs, data, len);
292 if (unlikely(ret < 0))
293 break;
294
295 ffs->state = FFS_READ_STRINGS;
296 ret = len;
297 } else {
298 pr_info("read strings\n");
299 ret = __ffs_data_got_strings(ffs, data, len);
300 if (unlikely(ret < 0))
301 break;
302
303 ret = ffs_epfiles_create(ffs);
304 if (unlikely(ret)) {
305 ffs->state = FFS_CLOSING;
306 break;
307 }
308
309 ffs->state = FFS_ACTIVE;
310 mutex_unlock(&ffs->mutex);
311
312 ret = ffs_ready(ffs);
313 if (unlikely(ret < 0)) {
314 ffs->state = FFS_CLOSING;
315 return ret;
316 }
317
318 return len;
319 }
320 break;
321
322 case FFS_ACTIVE:
323 data = NULL;
324 /*
325 * We're called from user space, we can use _irq
326 * rather then _irqsave
327 */
328 spin_lock_irq(&ffs->ev.waitq.lock);
329 switch (ffs_setup_state_clear_cancelled(ffs)) {
330 case FFS_SETUP_CANCELLED:
331 ret = -EIDRM;
332 goto done_spin;
333
334 case FFS_NO_SETUP:
335 ret = -ESRCH;
336 goto done_spin;
337
338 case FFS_SETUP_PENDING:
339 break;
340 }
341
342 /* FFS_SETUP_PENDING */
343 if (!(ffs->ev.setup.bRequestType & USB_DIR_IN)) {
344 spin_unlock_irq(&ffs->ev.waitq.lock);
345 ret = __ffs_ep0_stall(ffs);
346 break;
347 }
348
349 /* FFS_SETUP_PENDING and not stall */
350 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
351
352 spin_unlock_irq(&ffs->ev.waitq.lock);
353
354 data = ffs_prepare_buffer(buf, len);
355 if (IS_ERR(data)) {
356 ret = PTR_ERR(data);
357 break;
358 }
359
360 spin_lock_irq(&ffs->ev.waitq.lock);
361
362 /*
363 * We are guaranteed to be still in FFS_ACTIVE state
364 * but the state of setup could have changed from
365 * FFS_SETUP_PENDING to FFS_SETUP_CANCELLED so we need
366 * to check for that. If that happened we copied data
367 * from user space in vain but it's unlikely.
368 *
369 * For sure we are not in FFS_NO_SETUP since this is
370 * the only place FFS_SETUP_PENDING -> FFS_NO_SETUP
371 * transition can be performed and it's protected by
372 * mutex.
373 */
374 if (ffs_setup_state_clear_cancelled(ffs) ==
375 FFS_SETUP_CANCELLED) {
376 ret = -EIDRM;
377 done_spin:
378 spin_unlock_irq(&ffs->ev.waitq.lock);
379 } else {
380 /* unlocks spinlock */
381 ret = __ffs_ep0_queue_wait(ffs, data, len);
382 }
383 kfree(data);
384 break;
385
386 default:
387 ret = -EBADFD;
388 break;
389 }
390
391 mutex_unlock(&ffs->mutex);
392 return ret;
393 }
394
395 /* Called with ffs->ev.waitq.lock and ffs->mutex held, both released on exit. */
396 static ssize_t __ffs_ep0_read_events(struct ffs_data *ffs, char __user *buf,
397 size_t n)
398 {
399 /*
400 * n cannot be bigger than ffs->ev.count, which cannot be bigger than
401 * size of ffs->ev.types array (which is four) so that's how much space
402 * we reserve.
403 */
404 struct usb_functionfs_event events[ARRAY_SIZE(ffs->ev.types)];
405 const size_t size = n * sizeof *events;
406 unsigned i = 0;
407
408 memset(events, 0, size);
409
410 do {
411 events[i].type = ffs->ev.types[i];
412 if (events[i].type == FUNCTIONFS_SETUP) {
413 events[i].u.setup = ffs->ev.setup;
414 ffs->setup_state = FFS_SETUP_PENDING;
415 }
416 } while (++i < n);
417
418 ffs->ev.count -= n;
419 if (ffs->ev.count)
420 memmove(ffs->ev.types, ffs->ev.types + n,
421 ffs->ev.count * sizeof *ffs->ev.types);
422
423 spin_unlock_irq(&ffs->ev.waitq.lock);
424 mutex_unlock(&ffs->mutex);
425
426 return unlikely(__copy_to_user(buf, events, size)) ? -EFAULT : size;
427 }
428
429 static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
430 size_t len, loff_t *ptr)
431 {
432 struct ffs_data *ffs = file->private_data;
433 char *data = NULL;
434 size_t n;
435 int ret;
436
437 ENTER();
438
439 /* Fast check if setup was canceled */
440 if (ffs_setup_state_clear_cancelled(ffs) == FFS_SETUP_CANCELLED)
441 return -EIDRM;
442
443 /* Acquire mutex */
444 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
445 if (unlikely(ret < 0))
446 return ret;
447
448 /* Check state */
449 if (ffs->state != FFS_ACTIVE) {
450 ret = -EBADFD;
451 goto done_mutex;
452 }
453
454 /*
455 * We're called from user space, we can use _irq rather then
456 * _irqsave
457 */
458 spin_lock_irq(&ffs->ev.waitq.lock);
459
460 switch (ffs_setup_state_clear_cancelled(ffs)) {
461 case FFS_SETUP_CANCELLED:
462 ret = -EIDRM;
463 break;
464
465 case FFS_NO_SETUP:
466 n = len / sizeof(struct usb_functionfs_event);
467 if (unlikely(!n)) {
468 ret = -EINVAL;
469 break;
470 }
471
472 if ((file->f_flags & O_NONBLOCK) && !ffs->ev.count) {
473 ret = -EAGAIN;
474 break;
475 }
476
477 if (wait_event_interruptible_exclusive_locked_irq(ffs->ev.waitq,
478 ffs->ev.count)) {
479 ret = -EINTR;
480 break;
481 }
482
483 return __ffs_ep0_read_events(ffs, buf,
484 min(n, (size_t)ffs->ev.count));
485
486 case FFS_SETUP_PENDING:
487 if (ffs->ev.setup.bRequestType & USB_DIR_IN) {
488 spin_unlock_irq(&ffs->ev.waitq.lock);
489 ret = __ffs_ep0_stall(ffs);
490 goto done_mutex;
491 }
492
493 len = min(len, (size_t)le16_to_cpu(ffs->ev.setup.wLength));
494
495 spin_unlock_irq(&ffs->ev.waitq.lock);
496
497 if (likely(len)) {
498 data = kmalloc(len, GFP_KERNEL);
499 if (unlikely(!data)) {
500 ret = -ENOMEM;
501 goto done_mutex;
502 }
503 }
504
505 spin_lock_irq(&ffs->ev.waitq.lock);
506
507 /* See ffs_ep0_write() */
508 if (ffs_setup_state_clear_cancelled(ffs) ==
509 FFS_SETUP_CANCELLED) {
510 ret = -EIDRM;
511 break;
512 }
513
514 /* unlocks spinlock */
515 ret = __ffs_ep0_queue_wait(ffs, data, len);
516 if (likely(ret > 0) && unlikely(__copy_to_user(buf, data, len)))
517 ret = -EFAULT;
518 goto done_mutex;
519
520 default:
521 ret = -EBADFD;
522 break;
523 }
524
525 spin_unlock_irq(&ffs->ev.waitq.lock);
526 done_mutex:
527 mutex_unlock(&ffs->mutex);
528 kfree(data);
529 return ret;
530 }
531
532 static int ffs_ep0_open(struct inode *inode, struct file *file)
533 {
534 struct ffs_data *ffs = inode->i_private;
535
536 ENTER();
537
538 if (unlikely(ffs->state == FFS_CLOSING))
539 return -EBUSY;
540
541 file->private_data = ffs;
542 ffs_data_opened(ffs);
543
544 return 0;
545 }
546
547 static int ffs_ep0_release(struct inode *inode, struct file *file)
548 {
549 struct ffs_data *ffs = file->private_data;
550
551 ENTER();
552
553 ffs_data_closed(ffs);
554
555 return 0;
556 }
557
558 static long ffs_ep0_ioctl(struct file *file, unsigned code, unsigned long value)
559 {
560 struct ffs_data *ffs = file->private_data;
561 struct usb_gadget *gadget = ffs->gadget;
562 long ret;
563
564 ENTER();
565
566 if (code == FUNCTIONFS_INTERFACE_REVMAP) {
567 struct ffs_function *func = ffs->func;
568 ret = func ? ffs_func_revmap_intf(func, value) : -ENODEV;
569 } else if (gadget && gadget->ops->ioctl) {
570 ret = gadget->ops->ioctl(gadget, code, value);
571 } else {
572 ret = -ENOTTY;
573 }
574
575 return ret;
576 }
577
578 static unsigned int ffs_ep0_poll(struct file *file, poll_table *wait)
579 {
580 struct ffs_data *ffs = file->private_data;
581 unsigned int mask = POLLWRNORM;
582 int ret;
583
584 poll_wait(file, &ffs->ev.waitq, wait);
585
586 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
587 if (unlikely(ret < 0))
588 return mask;
589
590 switch (ffs->state) {
591 case FFS_READ_DESCRIPTORS:
592 case FFS_READ_STRINGS:
593 mask |= POLLOUT;
594 break;
595
596 case FFS_ACTIVE:
597 switch (ffs->setup_state) {
598 case FFS_NO_SETUP:
599 if (ffs->ev.count)
600 mask |= POLLIN;
601 break;
602
603 case FFS_SETUP_PENDING:
604 case FFS_SETUP_CANCELLED:
605 mask |= (POLLIN | POLLOUT);
606 break;
607 }
608 case FFS_CLOSING:
609 break;
610 case FFS_DEACTIVATED:
611 break;
612 }
613
614 mutex_unlock(&ffs->mutex);
615
616 return mask;
617 }
618
619 static const struct file_operations ffs_ep0_operations = {
620 .llseek = no_llseek,
621
622 .open = ffs_ep0_open,
623 .write = ffs_ep0_write,
624 .read = ffs_ep0_read,
625 .release = ffs_ep0_release,
626 .unlocked_ioctl = ffs_ep0_ioctl,
627 .poll = ffs_ep0_poll,
628 };
629
630
631 /* "Normal" endpoints operations ********************************************/
632
633 static void ffs_epfile_io_complete(struct usb_ep *_ep, struct usb_request *req)
634 {
635 ENTER();
636 if (likely(req->context)) {
637 struct ffs_ep *ep = _ep->driver_data;
638 ep->status = req->status ? req->status : req->actual;
639 complete(req->context);
640 }
641 }
642
643 static void ffs_user_copy_worker(struct work_struct *work)
644 {
645 struct ffs_io_data *io_data = container_of(work, struct ffs_io_data,
646 work);
647 int ret = io_data->req->status ? io_data->req->status :
648 io_data->req->actual;
649
650 if (io_data->read && ret > 0) {
651 use_mm(io_data->mm);
652 ret = copy_to_iter(io_data->buf, ret, &io_data->data);
653 if (iov_iter_count(&io_data->data))
654 ret = -EFAULT;
655 unuse_mm(io_data->mm);
656 }
657
658 io_data->kiocb->ki_complete(io_data->kiocb, ret, ret);
659
660 if (io_data->ffs->ffs_eventfd &&
661 !(io_data->kiocb->ki_flags & IOCB_EVENTFD))
662 eventfd_signal(io_data->ffs->ffs_eventfd, 1);
663
664 usb_ep_free_request(io_data->ep, io_data->req);
665
666 io_data->kiocb->private = NULL;
667 if (io_data->read)
668 kfree(io_data->to_free);
669 kfree(io_data->buf);
670 kfree(io_data);
671 }
672
673 static void ffs_epfile_async_io_complete(struct usb_ep *_ep,
674 struct usb_request *req)
675 {
676 struct ffs_io_data *io_data = req->context;
677
678 ENTER();
679
680 INIT_WORK(&io_data->work, ffs_user_copy_worker);
681 schedule_work(&io_data->work);
682 }
683
684 static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
685 {
686 struct ffs_epfile *epfile = file->private_data;
687 struct ffs_ep *ep;
688 char *data = NULL;
689 ssize_t ret, data_len = -EINVAL;
690 int halt;
691
692 /* Are we still active? */
693 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE)) {
694 ret = -ENODEV;
695 goto error;
696 }
697
698 /* Wait for endpoint to be enabled */
699 ep = epfile->ep;
700 if (!ep) {
701 if (file->f_flags & O_NONBLOCK) {
702 ret = -EAGAIN;
703 goto error;
704 }
705
706 ret = wait_event_interruptible(epfile->wait, (ep = epfile->ep));
707 if (ret) {
708 ret = -EINTR;
709 goto error;
710 }
711 }
712
713 /* Do we halt? */
714 halt = (!io_data->read == !epfile->in);
715 if (halt && epfile->isoc) {
716 ret = -EINVAL;
717 goto error;
718 }
719
720 /* Allocate & copy */
721 if (!halt) {
722 /*
723 * if we _do_ wait above, the epfile->ffs->gadget might be NULL
724 * before the waiting completes, so do not assign to 'gadget' earlier
725 */
726 struct usb_gadget *gadget = epfile->ffs->gadget;
727 size_t copied;
728
729 spin_lock_irq(&epfile->ffs->eps_lock);
730 /* In the meantime, endpoint got disabled or changed. */
731 if (epfile->ep != ep) {
732 spin_unlock_irq(&epfile->ffs->eps_lock);
733 return -ESHUTDOWN;
734 }
735 data_len = iov_iter_count(&io_data->data);
736 /*
737 * Controller may require buffer size to be aligned to
738 * maxpacketsize of an out endpoint.
739 */
740 if (io_data->read)
741 data_len = usb_ep_align_maybe(gadget, ep->ep, data_len);
742 spin_unlock_irq(&epfile->ffs->eps_lock);
743
744 data = kmalloc(data_len, GFP_KERNEL);
745 if (unlikely(!data))
746 return -ENOMEM;
747 if (!io_data->read) {
748 copied = copy_from_iter(data, data_len, &io_data->data);
749 if (copied != data_len) {
750 ret = -EFAULT;
751 goto error;
752 }
753 }
754 }
755
756 /* We will be using request */
757 ret = ffs_mutex_lock(&epfile->mutex, file->f_flags & O_NONBLOCK);
758 if (unlikely(ret))
759 goto error;
760
761 spin_lock_irq(&epfile->ffs->eps_lock);
762
763 if (epfile->ep != ep) {
764 /* In the meantime, endpoint got disabled or changed. */
765 ret = -ESHUTDOWN;
766 spin_unlock_irq(&epfile->ffs->eps_lock);
767 } else if (halt) {
768 /* Halt */
769 if (likely(epfile->ep == ep) && !WARN_ON(!ep->ep))
770 usb_ep_set_halt(ep->ep);
771 spin_unlock_irq(&epfile->ffs->eps_lock);
772 ret = -EBADMSG;
773 } else {
774 /* Fire the request */
775 struct usb_request *req;
776
777 /*
778 * Sanity Check: even though data_len can't be used
779 * uninitialized at the time I write this comment, some
780 * compilers complain about this situation.
781 * In order to keep the code clean from warnings, data_len is
782 * being initialized to -EINVAL during its declaration, which
783 * means we can't rely on compiler anymore to warn no future
784 * changes won't result in data_len being used uninitialized.
785 * For such reason, we're adding this redundant sanity check
786 * here.
787 */
788 if (unlikely(data_len == -EINVAL)) {
789 WARN(1, "%s: data_len == -EINVAL\n", __func__);
790 ret = -EINVAL;
791 goto error_lock;
792 }
793
794 if (io_data->aio) {
795 req = usb_ep_alloc_request(ep->ep, GFP_KERNEL);
796 if (unlikely(!req))
797 goto error_lock;
798
799 req->buf = data;
800 req->length = data_len;
801
802 io_data->buf = data;
803 io_data->ep = ep->ep;
804 io_data->req = req;
805 io_data->ffs = epfile->ffs;
806
807 req->context = io_data;
808 req->complete = ffs_epfile_async_io_complete;
809
810 ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
811 if (unlikely(ret)) {
812 usb_ep_free_request(ep->ep, req);
813 goto error_lock;
814 }
815 ret = -EIOCBQUEUED;
816
817 spin_unlock_irq(&epfile->ffs->eps_lock);
818 } else {
819 DECLARE_COMPLETION_ONSTACK(done);
820
821 req = ep->req;
822 req->buf = data;
823 req->length = data_len;
824
825 req->context = &done;
826 req->complete = ffs_epfile_io_complete;
827
828 ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
829
830 spin_unlock_irq(&epfile->ffs->eps_lock);
831
832 if (unlikely(ret < 0)) {
833 /* nop */
834 } else if (unlikely(
835 wait_for_completion_interruptible(&done))) {
836 ret = -EINTR;
837 usb_ep_dequeue(ep->ep, req);
838 } else {
839 /*
840 * XXX We may end up silently droping data
841 * here. Since data_len (i.e. req->length) may
842 * be bigger than len (after being rounded up
843 * to maxpacketsize), we may end up with more
844 * data then user space has space for.
845 */
846 ret = ep->status;
847 if (io_data->read && ret > 0) {
848 ret = copy_to_iter(data, ret, &io_data->data);
849 if (!ret)
850 ret = -EFAULT;
851 }
852 }
853 kfree(data);
854 }
855 }
856
857 mutex_unlock(&epfile->mutex);
858 return ret;
859
860 error_lock:
861 spin_unlock_irq(&epfile->ffs->eps_lock);
862 mutex_unlock(&epfile->mutex);
863 error:
864 kfree(data);
865 return ret;
866 }
867
868 static int
869 ffs_epfile_open(struct inode *inode, struct file *file)
870 {
871 struct ffs_epfile *epfile = inode->i_private;
872
873 ENTER();
874
875 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
876 return -ENODEV;
877
878 file->private_data = epfile;
879 ffs_data_opened(epfile->ffs);
880
881 return 0;
882 }
883
884 static int ffs_aio_cancel(struct kiocb *kiocb)
885 {
886 struct ffs_io_data *io_data = kiocb->private;
887 struct ffs_epfile *epfile = kiocb->ki_filp->private_data;
888 int value;
889
890 ENTER();
891
892 spin_lock_irq(&epfile->ffs->eps_lock);
893
894 if (likely(io_data && io_data->ep && io_data->req))
895 value = usb_ep_dequeue(io_data->ep, io_data->req);
896 else
897 value = -EINVAL;
898
899 spin_unlock_irq(&epfile->ffs->eps_lock);
900
901 return value;
902 }
903
904 static ssize_t ffs_epfile_write_iter(struct kiocb *kiocb, struct iov_iter *from)
905 {
906 struct ffs_io_data io_data, *p = &io_data;
907 ssize_t res;
908
909 ENTER();
910
911 if (!is_sync_kiocb(kiocb)) {
912 p = kmalloc(sizeof(io_data), GFP_KERNEL);
913 if (unlikely(!p))
914 return -ENOMEM;
915 p->aio = true;
916 } else {
917 p->aio = false;
918 }
919
920 p->read = false;
921 p->kiocb = kiocb;
922 p->data = *from;
923 p->mm = current->mm;
924
925 kiocb->private = p;
926
927 kiocb_set_cancel_fn(kiocb, ffs_aio_cancel);
928
929 res = ffs_epfile_io(kiocb->ki_filp, p);
930 if (res == -EIOCBQUEUED)
931 return res;
932 if (p->aio)
933 kfree(p);
934 else
935 *from = p->data;
936 return res;
937 }
938
939 static ssize_t ffs_epfile_read_iter(struct kiocb *kiocb, struct iov_iter *to)
940 {
941 struct ffs_io_data io_data, *p = &io_data;
942 ssize_t res;
943
944 ENTER();
945
946 if (!is_sync_kiocb(kiocb)) {
947 p = kmalloc(sizeof(io_data), GFP_KERNEL);
948 if (unlikely(!p))
949 return -ENOMEM;
950 p->aio = true;
951 } else {
952 p->aio = false;
953 }
954
955 p->read = true;
956 p->kiocb = kiocb;
957 if (p->aio) {
958 p->to_free = dup_iter(&p->data, to, GFP_KERNEL);
959 if (!p->to_free) {
960 kfree(p);
961 return -ENOMEM;
962 }
963 } else {
964 p->data = *to;
965 p->to_free = NULL;
966 }
967 p->mm = current->mm;
968
969 kiocb->private = p;
970
971 kiocb_set_cancel_fn(kiocb, ffs_aio_cancel);
972
973 res = ffs_epfile_io(kiocb->ki_filp, p);
974 if (res == -EIOCBQUEUED)
975 return res;
976
977 if (p->aio) {
978 kfree(p->to_free);
979 kfree(p);
980 } else {
981 *to = p->data;
982 }
983 return res;
984 }
985
986 static int
987 ffs_epfile_release(struct inode *inode, struct file *file)
988 {
989 struct ffs_epfile *epfile = inode->i_private;
990
991 ENTER();
992
993 ffs_data_closed(epfile->ffs);
994
995 return 0;
996 }
997
998 static long ffs_epfile_ioctl(struct file *file, unsigned code,
999 unsigned long value)
1000 {
1001 struct ffs_epfile *epfile = file->private_data;
1002 int ret;
1003
1004 ENTER();
1005
1006 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE))
1007 return -ENODEV;
1008
1009 spin_lock_irq(&epfile->ffs->eps_lock);
1010 if (likely(epfile->ep)) {
1011 switch (code) {
1012 case FUNCTIONFS_FIFO_STATUS:
1013 ret = usb_ep_fifo_status(epfile->ep->ep);
1014 break;
1015 case FUNCTIONFS_FIFO_FLUSH:
1016 usb_ep_fifo_flush(epfile->ep->ep);
1017 ret = 0;
1018 break;
1019 case FUNCTIONFS_CLEAR_HALT:
1020 ret = usb_ep_clear_halt(epfile->ep->ep);
1021 break;
1022 case FUNCTIONFS_ENDPOINT_REVMAP:
1023 ret = epfile->ep->num;
1024 break;
1025 case FUNCTIONFS_ENDPOINT_DESC:
1026 {
1027 int desc_idx;
1028 struct usb_endpoint_descriptor *desc;
1029
1030 switch (epfile->ffs->gadget->speed) {
1031 case USB_SPEED_SUPER:
1032 desc_idx = 2;
1033 break;
1034 case USB_SPEED_HIGH:
1035 desc_idx = 1;
1036 break;
1037 default:
1038 desc_idx = 0;
1039 }
1040 desc = epfile->ep->descs[desc_idx];
1041
1042 spin_unlock_irq(&epfile->ffs->eps_lock);
1043 ret = copy_to_user((void *)value, desc, sizeof(*desc));
1044 if (ret)
1045 ret = -EFAULT;
1046 return ret;
1047 }
1048 default:
1049 ret = -ENOTTY;
1050 }
1051 } else {
1052 ret = -ENODEV;
1053 }
1054 spin_unlock_irq(&epfile->ffs->eps_lock);
1055
1056 return ret;
1057 }
1058
1059 static const struct file_operations ffs_epfile_operations = {
1060 .llseek = no_llseek,
1061
1062 .open = ffs_epfile_open,
1063 .write_iter = ffs_epfile_write_iter,
1064 .read_iter = ffs_epfile_read_iter,
1065 .release = ffs_epfile_release,
1066 .unlocked_ioctl = ffs_epfile_ioctl,
1067 };
1068
1069
1070 /* File system and super block operations ***********************************/
1071
1072 /*
1073 * Mounting the file system creates a controller file, used first for
1074 * function configuration then later for event monitoring.
1075 */
1076
1077 static struct inode *__must_check
1078 ffs_sb_make_inode(struct super_block *sb, void *data,
1079 const struct file_operations *fops,
1080 const struct inode_operations *iops,
1081 struct ffs_file_perms *perms)
1082 {
1083 struct inode *inode;
1084
1085 ENTER();
1086
1087 inode = new_inode(sb);
1088
1089 if (likely(inode)) {
1090 struct timespec current_time = CURRENT_TIME;
1091
1092 inode->i_ino = get_next_ino();
1093 inode->i_mode = perms->mode;
1094 inode->i_uid = perms->uid;
1095 inode->i_gid = perms->gid;
1096 inode->i_atime = current_time;
1097 inode->i_mtime = current_time;
1098 inode->i_ctime = current_time;
1099 inode->i_private = data;
1100 if (fops)
1101 inode->i_fop = fops;
1102 if (iops)
1103 inode->i_op = iops;
1104 }
1105
1106 return inode;
1107 }
1108
1109 /* Create "regular" file */
1110 static struct dentry *ffs_sb_create_file(struct super_block *sb,
1111 const char *name, void *data,
1112 const struct file_operations *fops)
1113 {
1114 struct ffs_data *ffs = sb->s_fs_info;
1115 struct dentry *dentry;
1116 struct inode *inode;
1117
1118 ENTER();
1119
1120 dentry = d_alloc_name(sb->s_root, name);
1121 if (unlikely(!dentry))
1122 return NULL;
1123
1124 inode = ffs_sb_make_inode(sb, data, fops, NULL, &ffs->file_perms);
1125 if (unlikely(!inode)) {
1126 dput(dentry);
1127 return NULL;
1128 }
1129
1130 d_add(dentry, inode);
1131 return dentry;
1132 }
1133
1134 /* Super block */
1135 static const struct super_operations ffs_sb_operations = {
1136 .statfs = simple_statfs,
1137 .drop_inode = generic_delete_inode,
1138 };
1139
1140 struct ffs_sb_fill_data {
1141 struct ffs_file_perms perms;
1142 umode_t root_mode;
1143 const char *dev_name;
1144 bool no_disconnect;
1145 struct ffs_data *ffs_data;
1146 };
1147
1148 static int ffs_sb_fill(struct super_block *sb, void *_data, int silent)
1149 {
1150 struct ffs_sb_fill_data *data = _data;
1151 struct inode *inode;
1152 struct ffs_data *ffs = data->ffs_data;
1153
1154 ENTER();
1155
1156 ffs->sb = sb;
1157 data->ffs_data = NULL;
1158 sb->s_fs_info = ffs;
1159 sb->s_blocksize = PAGE_CACHE_SIZE;
1160 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
1161 sb->s_magic = FUNCTIONFS_MAGIC;
1162 sb->s_op = &ffs_sb_operations;
1163 sb->s_time_gran = 1;
1164
1165 /* Root inode */
1166 data->perms.mode = data->root_mode;
1167 inode = ffs_sb_make_inode(sb, NULL,
1168 &simple_dir_operations,
1169 &simple_dir_inode_operations,
1170 &data->perms);
1171 sb->s_root = d_make_root(inode);
1172 if (unlikely(!sb->s_root))
1173 return -ENOMEM;
1174
1175 /* EP0 file */
1176 if (unlikely(!ffs_sb_create_file(sb, "ep0", ffs,
1177 &ffs_ep0_operations)))
1178 return -ENOMEM;
1179
1180 return 0;
1181 }
1182
1183 static int ffs_fs_parse_opts(struct ffs_sb_fill_data *data, char *opts)
1184 {
1185 ENTER();
1186
1187 if (!opts || !*opts)
1188 return 0;
1189
1190 for (;;) {
1191 unsigned long value;
1192 char *eq, *comma;
1193
1194 /* Option limit */
1195 comma = strchr(opts, ',');
1196 if (comma)
1197 *comma = 0;
1198
1199 /* Value limit */
1200 eq = strchr(opts, '=');
1201 if (unlikely(!eq)) {
1202 pr_err("'=' missing in %s\n", opts);
1203 return -EINVAL;
1204 }
1205 *eq = 0;
1206
1207 /* Parse value */
1208 if (kstrtoul(eq + 1, 0, &value)) {
1209 pr_err("%s: invalid value: %s\n", opts, eq + 1);
1210 return -EINVAL;
1211 }
1212
1213 /* Interpret option */
1214 switch (eq - opts) {
1215 case 13:
1216 if (!memcmp(opts, "no_disconnect", 13))
1217 data->no_disconnect = !!value;
1218 else
1219 goto invalid;
1220 break;
1221 case 5:
1222 if (!memcmp(opts, "rmode", 5))
1223 data->root_mode = (value & 0555) | S_IFDIR;
1224 else if (!memcmp(opts, "fmode", 5))
1225 data->perms.mode = (value & 0666) | S_IFREG;
1226 else
1227 goto invalid;
1228 break;
1229
1230 case 4:
1231 if (!memcmp(opts, "mode", 4)) {
1232 data->root_mode = (value & 0555) | S_IFDIR;
1233 data->perms.mode = (value & 0666) | S_IFREG;
1234 } else {
1235 goto invalid;
1236 }
1237 break;
1238
1239 case 3:
1240 if (!memcmp(opts, "uid", 3)) {
1241 data->perms.uid = make_kuid(current_user_ns(), value);
1242 if (!uid_valid(data->perms.uid)) {
1243 pr_err("%s: unmapped value: %lu\n", opts, value);
1244 return -EINVAL;
1245 }
1246 } else if (!memcmp(opts, "gid", 3)) {
1247 data->perms.gid = make_kgid(current_user_ns(), value);
1248 if (!gid_valid(data->perms.gid)) {
1249 pr_err("%s: unmapped value: %lu\n", opts, value);
1250 return -EINVAL;
1251 }
1252 } else {
1253 goto invalid;
1254 }
1255 break;
1256
1257 default:
1258 invalid:
1259 pr_err("%s: invalid option\n", opts);
1260 return -EINVAL;
1261 }
1262
1263 /* Next iteration */
1264 if (!comma)
1265 break;
1266 opts = comma + 1;
1267 }
1268
1269 return 0;
1270 }
1271
1272 /* "mount -t functionfs dev_name /dev/function" ends up here */
1273
1274 static struct dentry *
1275 ffs_fs_mount(struct file_system_type *t, int flags,
1276 const char *dev_name, void *opts)
1277 {
1278 struct ffs_sb_fill_data data = {
1279 .perms = {
1280 .mode = S_IFREG | 0600,
1281 .uid = GLOBAL_ROOT_UID,
1282 .gid = GLOBAL_ROOT_GID,
1283 },
1284 .root_mode = S_IFDIR | 0500,
1285 .no_disconnect = false,
1286 };
1287 struct dentry *rv;
1288 int ret;
1289 void *ffs_dev;
1290 struct ffs_data *ffs;
1291
1292 ENTER();
1293
1294 ret = ffs_fs_parse_opts(&data, opts);
1295 if (unlikely(ret < 0))
1296 return ERR_PTR(ret);
1297
1298 ffs = ffs_data_new();
1299 if (unlikely(!ffs))
1300 return ERR_PTR(-ENOMEM);
1301 ffs->file_perms = data.perms;
1302 ffs->no_disconnect = data.no_disconnect;
1303
1304 ffs->dev_name = kstrdup(dev_name, GFP_KERNEL);
1305 if (unlikely(!ffs->dev_name)) {
1306 ffs_data_put(ffs);
1307 return ERR_PTR(-ENOMEM);
1308 }
1309
1310 ffs_dev = ffs_acquire_dev(dev_name);
1311 if (IS_ERR(ffs_dev)) {
1312 ffs_data_put(ffs);
1313 return ERR_CAST(ffs_dev);
1314 }
1315 ffs->private_data = ffs_dev;
1316 data.ffs_data = ffs;
1317
1318 rv = mount_nodev(t, flags, &data, ffs_sb_fill);
1319 if (IS_ERR(rv) && data.ffs_data) {
1320 ffs_release_dev(data.ffs_data);
1321 ffs_data_put(data.ffs_data);
1322 }
1323 return rv;
1324 }
1325
1326 static void
1327 ffs_fs_kill_sb(struct super_block *sb)
1328 {
1329 ENTER();
1330
1331 kill_litter_super(sb);
1332 if (sb->s_fs_info) {
1333 ffs_release_dev(sb->s_fs_info);
1334 ffs_data_closed(sb->s_fs_info);
1335 ffs_data_put(sb->s_fs_info);
1336 }
1337 }
1338
1339 static struct file_system_type ffs_fs_type = {
1340 .owner = THIS_MODULE,
1341 .name = "functionfs",
1342 .mount = ffs_fs_mount,
1343 .kill_sb = ffs_fs_kill_sb,
1344 };
1345 MODULE_ALIAS_FS("functionfs");
1346
1347
1348 /* Driver's main init/cleanup functions *************************************/
1349
1350 static int functionfs_init(void)
1351 {
1352 int ret;
1353
1354 ENTER();
1355
1356 ret = register_filesystem(&ffs_fs_type);
1357 if (likely(!ret))
1358 pr_info("file system registered\n");
1359 else
1360 pr_err("failed registering file system (%d)\n", ret);
1361
1362 return ret;
1363 }
1364
1365 static void functionfs_cleanup(void)
1366 {
1367 ENTER();
1368
1369 pr_info("unloading\n");
1370 unregister_filesystem(&ffs_fs_type);
1371 }
1372
1373
1374 /* ffs_data and ffs_function construction and destruction code **************/
1375
1376 static void ffs_data_clear(struct ffs_data *ffs);
1377 static void ffs_data_reset(struct ffs_data *ffs);
1378
1379 static void ffs_data_get(struct ffs_data *ffs)
1380 {
1381 ENTER();
1382
1383 atomic_inc(&ffs->ref);
1384 }
1385
1386 static void ffs_data_opened(struct ffs_data *ffs)
1387 {
1388 ENTER();
1389
1390 atomic_inc(&ffs->ref);
1391 if (atomic_add_return(1, &ffs->opened) == 1 &&
1392 ffs->state == FFS_DEACTIVATED) {
1393 ffs->state = FFS_CLOSING;
1394 ffs_data_reset(ffs);
1395 }
1396 }
1397
1398 static void ffs_data_put(struct ffs_data *ffs)
1399 {
1400 ENTER();
1401
1402 if (unlikely(atomic_dec_and_test(&ffs->ref))) {
1403 pr_info("%s(): freeing\n", __func__);
1404 ffs_data_clear(ffs);
1405 BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
1406 waitqueue_active(&ffs->ep0req_completion.wait));
1407 kfree(ffs->dev_name);
1408 kfree(ffs);
1409 }
1410 }
1411
1412 static void ffs_data_closed(struct ffs_data *ffs)
1413 {
1414 ENTER();
1415
1416 if (atomic_dec_and_test(&ffs->opened)) {
1417 if (ffs->no_disconnect) {
1418 ffs->state = FFS_DEACTIVATED;
1419 if (ffs->epfiles) {
1420 ffs_epfiles_destroy(ffs->epfiles,
1421 ffs->eps_count);
1422 ffs->epfiles = NULL;
1423 }
1424 if (ffs->setup_state == FFS_SETUP_PENDING)
1425 __ffs_ep0_stall(ffs);
1426 } else {
1427 ffs->state = FFS_CLOSING;
1428 ffs_data_reset(ffs);
1429 }
1430 }
1431 if (atomic_read(&ffs->opened) < 0) {
1432 ffs->state = FFS_CLOSING;
1433 ffs_data_reset(ffs);
1434 }
1435
1436 ffs_data_put(ffs);
1437 }
1438
1439 static struct ffs_data *ffs_data_new(void)
1440 {
1441 struct ffs_data *ffs = kzalloc(sizeof *ffs, GFP_KERNEL);
1442 if (unlikely(!ffs))
1443 return NULL;
1444
1445 ENTER();
1446
1447 atomic_set(&ffs->ref, 1);
1448 atomic_set(&ffs->opened, 0);
1449 ffs->state = FFS_READ_DESCRIPTORS;
1450 mutex_init(&ffs->mutex);
1451 spin_lock_init(&ffs->eps_lock);
1452 init_waitqueue_head(&ffs->ev.waitq);
1453 init_completion(&ffs->ep0req_completion);
1454
1455 /* XXX REVISIT need to update it in some places, or do we? */
1456 ffs->ev.can_stall = 1;
1457
1458 return ffs;
1459 }
1460
1461 static void ffs_data_clear(struct ffs_data *ffs)
1462 {
1463 ENTER();
1464
1465 ffs_closed(ffs);
1466
1467 BUG_ON(ffs->gadget);
1468
1469 if (ffs->epfiles)
1470 ffs_epfiles_destroy(ffs->epfiles, ffs->eps_count);
1471
1472 if (ffs->ffs_eventfd)
1473 eventfd_ctx_put(ffs->ffs_eventfd);
1474
1475 kfree(ffs->raw_descs_data);
1476 kfree(ffs->raw_strings);
1477 kfree(ffs->stringtabs);
1478 }
1479
1480 static void ffs_data_reset(struct ffs_data *ffs)
1481 {
1482 ENTER();
1483
1484 ffs_data_clear(ffs);
1485
1486 ffs->epfiles = NULL;
1487 ffs->raw_descs_data = NULL;
1488 ffs->raw_descs = NULL;
1489 ffs->raw_strings = NULL;
1490 ffs->stringtabs = NULL;
1491
1492 ffs->raw_descs_length = 0;
1493 ffs->fs_descs_count = 0;
1494 ffs->hs_descs_count = 0;
1495 ffs->ss_descs_count = 0;
1496
1497 ffs->strings_count = 0;
1498 ffs->interfaces_count = 0;
1499 ffs->eps_count = 0;
1500
1501 ffs->ev.count = 0;
1502
1503 ffs->state = FFS_READ_DESCRIPTORS;
1504 ffs->setup_state = FFS_NO_SETUP;
1505 ffs->flags = 0;
1506 }
1507
1508
1509 static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
1510 {
1511 struct usb_gadget_strings **lang;
1512 int first_id;
1513
1514 ENTER();
1515
1516 if (WARN_ON(ffs->state != FFS_ACTIVE
1517 || test_and_set_bit(FFS_FL_BOUND, &ffs->flags)))
1518 return -EBADFD;
1519
1520 first_id = usb_string_ids_n(cdev, ffs->strings_count);
1521 if (unlikely(first_id < 0))
1522 return first_id;
1523
1524 ffs->ep0req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
1525 if (unlikely(!ffs->ep0req))
1526 return -ENOMEM;
1527 ffs->ep0req->complete = ffs_ep0_complete;
1528 ffs->ep0req->context = ffs;
1529
1530 lang = ffs->stringtabs;
1531 if (lang) {
1532 for (; *lang; ++lang) {
1533 struct usb_string *str = (*lang)->strings;
1534 int id = first_id;
1535 for (; str->s; ++id, ++str)
1536 str->id = id;
1537 }
1538 }
1539
1540 ffs->gadget = cdev->gadget;
1541 ffs_data_get(ffs);
1542 return 0;
1543 }
1544
1545 static void functionfs_unbind(struct ffs_data *ffs)
1546 {
1547 ENTER();
1548
1549 if (!WARN_ON(!ffs->gadget)) {
1550 usb_ep_free_request(ffs->gadget->ep0, ffs->ep0req);
1551 ffs->ep0req = NULL;
1552 ffs->gadget = NULL;
1553 clear_bit(FFS_FL_BOUND, &ffs->flags);
1554 ffs_data_put(ffs);
1555 }
1556 }
1557
1558 static int ffs_epfiles_create(struct ffs_data *ffs)
1559 {
1560 struct ffs_epfile *epfile, *epfiles;
1561 unsigned i, count;
1562
1563 ENTER();
1564
1565 count = ffs->eps_count;
1566 epfiles = kcalloc(count, sizeof(*epfiles), GFP_KERNEL);
1567 if (!epfiles)
1568 return -ENOMEM;
1569
1570 epfile = epfiles;
1571 for (i = 1; i <= count; ++i, ++epfile) {
1572 epfile->ffs = ffs;
1573 mutex_init(&epfile->mutex);
1574 init_waitqueue_head(&epfile->wait);
1575 if (ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
1576 sprintf(epfile->name, "ep%02x", ffs->eps_addrmap[i]);
1577 else
1578 sprintf(epfile->name, "ep%u", i);
1579 epfile->dentry = ffs_sb_create_file(ffs->sb, epfile->name,
1580 epfile,
1581 &ffs_epfile_operations);
1582 if (unlikely(!epfile->dentry)) {
1583 ffs_epfiles_destroy(epfiles, i - 1);
1584 return -ENOMEM;
1585 }
1586 }
1587
1588 ffs->epfiles = epfiles;
1589 return 0;
1590 }
1591
1592 static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count)
1593 {
1594 struct ffs_epfile *epfile = epfiles;
1595
1596 ENTER();
1597
1598 for (; count; --count, ++epfile) {
1599 BUG_ON(mutex_is_locked(&epfile->mutex) ||
1600 waitqueue_active(&epfile->wait));
1601 if (epfile->dentry) {
1602 d_delete(epfile->dentry);
1603 dput(epfile->dentry);
1604 epfile->dentry = NULL;
1605 }
1606 }
1607
1608 kfree(epfiles);
1609 }
1610
1611 static void ffs_func_eps_disable(struct ffs_function *func)
1612 {
1613 struct ffs_ep *ep = func->eps;
1614 struct ffs_epfile *epfile = func->ffs->epfiles;
1615 unsigned count = func->ffs->eps_count;
1616 unsigned long flags;
1617
1618 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1619 do {
1620 /* pending requests get nuked */
1621 if (likely(ep->ep))
1622 usb_ep_disable(ep->ep);
1623 ++ep;
1624
1625 if (epfile) {
1626 epfile->ep = NULL;
1627 ++epfile;
1628 }
1629 } while (--count);
1630 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1631 }
1632
1633 static int ffs_func_eps_enable(struct ffs_function *func)
1634 {
1635 struct ffs_data *ffs = func->ffs;
1636 struct ffs_ep *ep = func->eps;
1637 struct ffs_epfile *epfile = ffs->epfiles;
1638 unsigned count = ffs->eps_count;
1639 unsigned long flags;
1640 int ret = 0;
1641
1642 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1643 do {
1644 struct usb_endpoint_descriptor *ds;
1645 int desc_idx;
1646
1647 if (ffs->gadget->speed == USB_SPEED_SUPER)
1648 desc_idx = 2;
1649 else if (ffs->gadget->speed == USB_SPEED_HIGH)
1650 desc_idx = 1;
1651 else
1652 desc_idx = 0;
1653
1654 /* fall-back to lower speed if desc missing for current speed */
1655 do {
1656 ds = ep->descs[desc_idx];
1657 } while (!ds && --desc_idx >= 0);
1658
1659 if (!ds) {
1660 ret = -EINVAL;
1661 break;
1662 }
1663
1664 ep->ep->driver_data = ep;
1665 ep->ep->desc = ds;
1666 ret = usb_ep_enable(ep->ep);
1667 if (likely(!ret)) {
1668 epfile->ep = ep;
1669 epfile->in = usb_endpoint_dir_in(ds);
1670 epfile->isoc = usb_endpoint_xfer_isoc(ds);
1671 } else {
1672 break;
1673 }
1674
1675 wake_up(&epfile->wait);
1676
1677 ++ep;
1678 ++epfile;
1679 } while (--count);
1680 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1681
1682 return ret;
1683 }
1684
1685
1686 /* Parsing and building descriptors and strings *****************************/
1687
1688 /*
1689 * This validates if data pointed by data is a valid USB descriptor as
1690 * well as record how many interfaces, endpoints and strings are
1691 * required by given configuration. Returns address after the
1692 * descriptor or NULL if data is invalid.
1693 */
1694
1695 enum ffs_entity_type {
1696 FFS_DESCRIPTOR, FFS_INTERFACE, FFS_STRING, FFS_ENDPOINT
1697 };
1698
1699 enum ffs_os_desc_type {
1700 FFS_OS_DESC, FFS_OS_DESC_EXT_COMPAT, FFS_OS_DESC_EXT_PROP
1701 };
1702
1703 typedef int (*ffs_entity_callback)(enum ffs_entity_type entity,
1704 u8 *valuep,
1705 struct usb_descriptor_header *desc,
1706 void *priv);
1707
1708 typedef int (*ffs_os_desc_callback)(enum ffs_os_desc_type entity,
1709 struct usb_os_desc_header *h, void *data,
1710 unsigned len, void *priv);
1711
1712 static int __must_check ffs_do_single_desc(char *data, unsigned len,
1713 ffs_entity_callback entity,
1714 void *priv)
1715 {
1716 struct usb_descriptor_header *_ds = (void *)data;
1717 u8 length;
1718 int ret;
1719
1720 ENTER();
1721
1722 /* At least two bytes are required: length and type */
1723 if (len < 2) {
1724 pr_vdebug("descriptor too short\n");
1725 return -EINVAL;
1726 }
1727
1728 /* If we have at least as many bytes as the descriptor takes? */
1729 length = _ds->bLength;
1730 if (len < length) {
1731 pr_vdebug("descriptor longer then available data\n");
1732 return -EINVAL;
1733 }
1734
1735 #define __entity_check_INTERFACE(val) 1
1736 #define __entity_check_STRING(val) (val)
1737 #define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
1738 #define __entity(type, val) do { \
1739 pr_vdebug("entity " #type "(%02x)\n", (val)); \
1740 if (unlikely(!__entity_check_ ##type(val))) { \
1741 pr_vdebug("invalid entity's value\n"); \
1742 return -EINVAL; \
1743 } \
1744 ret = entity(FFS_ ##type, &val, _ds, priv); \
1745 if (unlikely(ret < 0)) { \
1746 pr_debug("entity " #type "(%02x); ret = %d\n", \
1747 (val), ret); \
1748 return ret; \
1749 } \
1750 } while (0)
1751
1752 /* Parse descriptor depending on type. */
1753 switch (_ds->bDescriptorType) {
1754 case USB_DT_DEVICE:
1755 case USB_DT_CONFIG:
1756 case USB_DT_STRING:
1757 case USB_DT_DEVICE_QUALIFIER:
1758 /* function can't have any of those */
1759 pr_vdebug("descriptor reserved for gadget: %d\n",
1760 _ds->bDescriptorType);
1761 return -EINVAL;
1762
1763 case USB_DT_INTERFACE: {
1764 struct usb_interface_descriptor *ds = (void *)_ds;
1765 pr_vdebug("interface descriptor\n");
1766 if (length != sizeof *ds)
1767 goto inv_length;
1768
1769 __entity(INTERFACE, ds->bInterfaceNumber);
1770 if (ds->iInterface)
1771 __entity(STRING, ds->iInterface);
1772 }
1773 break;
1774
1775 case USB_DT_ENDPOINT: {
1776 struct usb_endpoint_descriptor *ds = (void *)_ds;
1777 pr_vdebug("endpoint descriptor\n");
1778 if (length != USB_DT_ENDPOINT_SIZE &&
1779 length != USB_DT_ENDPOINT_AUDIO_SIZE)
1780 goto inv_length;
1781 __entity(ENDPOINT, ds->bEndpointAddress);
1782 }
1783 break;
1784
1785 case HID_DT_HID:
1786 pr_vdebug("hid descriptor\n");
1787 if (length != sizeof(struct hid_descriptor))
1788 goto inv_length;
1789 break;
1790
1791 case USB_DT_OTG:
1792 if (length != sizeof(struct usb_otg_descriptor))
1793 goto inv_length;
1794 break;
1795
1796 case USB_DT_INTERFACE_ASSOCIATION: {
1797 struct usb_interface_assoc_descriptor *ds = (void *)_ds;
1798 pr_vdebug("interface association descriptor\n");
1799 if (length != sizeof *ds)
1800 goto inv_length;
1801 if (ds->iFunction)
1802 __entity(STRING, ds->iFunction);
1803 }
1804 break;
1805
1806 case USB_DT_SS_ENDPOINT_COMP:
1807 pr_vdebug("EP SS companion descriptor\n");
1808 if (length != sizeof(struct usb_ss_ep_comp_descriptor))
1809 goto inv_length;
1810 break;
1811
1812 case USB_DT_OTHER_SPEED_CONFIG:
1813 case USB_DT_INTERFACE_POWER:
1814 case USB_DT_DEBUG:
1815 case USB_DT_SECURITY:
1816 case USB_DT_CS_RADIO_CONTROL:
1817 /* TODO */
1818 pr_vdebug("unimplemented descriptor: %d\n", _ds->bDescriptorType);
1819 return -EINVAL;
1820
1821 default:
1822 /* We should never be here */
1823 pr_vdebug("unknown descriptor: %d\n", _ds->bDescriptorType);
1824 return -EINVAL;
1825
1826 inv_length:
1827 pr_vdebug("invalid length: %d (descriptor %d)\n",
1828 _ds->bLength, _ds->bDescriptorType);
1829 return -EINVAL;
1830 }
1831
1832 #undef __entity
1833 #undef __entity_check_DESCRIPTOR
1834 #undef __entity_check_INTERFACE
1835 #undef __entity_check_STRING
1836 #undef __entity_check_ENDPOINT
1837
1838 return length;
1839 }
1840
1841 static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
1842 ffs_entity_callback entity, void *priv)
1843 {
1844 const unsigned _len = len;
1845 unsigned long num = 0;
1846
1847 ENTER();
1848
1849 for (;;) {
1850 int ret;
1851
1852 if (num == count)
1853 data = NULL;
1854
1855 /* Record "descriptor" entity */
1856 ret = entity(FFS_DESCRIPTOR, (u8 *)num, (void *)data, priv);
1857 if (unlikely(ret < 0)) {
1858 pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
1859 num, ret);
1860 return ret;
1861 }
1862
1863 if (!data)
1864 return _len - len;
1865
1866 ret = ffs_do_single_desc(data, len, entity, priv);
1867 if (unlikely(ret < 0)) {
1868 pr_debug("%s returns %d\n", __func__, ret);
1869 return ret;
1870 }
1871
1872 len -= ret;
1873 data += ret;
1874 ++num;
1875 }
1876 }
1877
1878 static int __ffs_data_do_entity(enum ffs_entity_type type,
1879 u8 *valuep, struct usb_descriptor_header *desc,
1880 void *priv)
1881 {
1882 struct ffs_desc_helper *helper = priv;
1883 struct usb_endpoint_descriptor *d;
1884
1885 ENTER();
1886
1887 switch (type) {
1888 case FFS_DESCRIPTOR:
1889 break;
1890
1891 case FFS_INTERFACE:
1892 /*
1893 * Interfaces are indexed from zero so if we
1894 * encountered interface "n" then there are at least
1895 * "n+1" interfaces.
1896 */
1897 if (*valuep >= helper->interfaces_count)
1898 helper->interfaces_count = *valuep + 1;
1899 break;
1900
1901 case FFS_STRING:
1902 /*
1903 * Strings are indexed from 1 (0 is magic ;) reserved
1904 * for languages list or some such)
1905 */
1906 if (*valuep > helper->ffs->strings_count)
1907 helper->ffs->strings_count = *valuep;
1908 break;
1909
1910 case FFS_ENDPOINT:
1911 d = (void *)desc;
1912 helper->eps_count++;
1913 if (helper->eps_count >= 15)
1914 return -EINVAL;
1915 /* Check if descriptors for any speed were already parsed */
1916 if (!helper->ffs->eps_count && !helper->ffs->interfaces_count)
1917 helper->ffs->eps_addrmap[helper->eps_count] =
1918 d->bEndpointAddress;
1919 else if (helper->ffs->eps_addrmap[helper->eps_count] !=
1920 d->bEndpointAddress)
1921 return -EINVAL;
1922 break;
1923 }
1924
1925 return 0;
1926 }
1927
1928 static int __ffs_do_os_desc_header(enum ffs_os_desc_type *next_type,
1929 struct usb_os_desc_header *desc)
1930 {
1931 u16 bcd_version = le16_to_cpu(desc->bcdVersion);
1932 u16 w_index = le16_to_cpu(desc->wIndex);
1933
1934 if (bcd_version != 1) {
1935 pr_vdebug("unsupported os descriptors version: %d",
1936 bcd_version);
1937 return -EINVAL;
1938 }
1939 switch (w_index) {
1940 case 0x4:
1941 *next_type = FFS_OS_DESC_EXT_COMPAT;
1942 break;
1943 case 0x5:
1944 *next_type = FFS_OS_DESC_EXT_PROP;
1945 break;
1946 default:
1947 pr_vdebug("unsupported os descriptor type: %d", w_index);
1948 return -EINVAL;
1949 }
1950
1951 return sizeof(*desc);
1952 }
1953
1954 /*
1955 * Process all extended compatibility/extended property descriptors
1956 * of a feature descriptor
1957 */
1958 static int __must_check ffs_do_single_os_desc(char *data, unsigned len,
1959 enum ffs_os_desc_type type,
1960 u16 feature_count,
1961 ffs_os_desc_callback entity,
1962 void *priv,
1963 struct usb_os_desc_header *h)
1964 {
1965 int ret;
1966 const unsigned _len = len;
1967
1968 ENTER();
1969
1970 /* loop over all ext compat/ext prop descriptors */
1971 while (feature_count--) {
1972 ret = entity(type, h, data, len, priv);
1973 if (unlikely(ret < 0)) {
1974 pr_debug("bad OS descriptor, type: %d\n", type);
1975 return ret;
1976 }
1977 data += ret;
1978 len -= ret;
1979 }
1980 return _len - len;
1981 }
1982
1983 /* Process a number of complete Feature Descriptors (Ext Compat or Ext Prop) */
1984 static int __must_check ffs_do_os_descs(unsigned count,
1985 char *data, unsigned len,
1986 ffs_os_desc_callback entity, void *priv)
1987 {
1988 const unsigned _len = len;
1989 unsigned long num = 0;
1990
1991 ENTER();
1992
1993 for (num = 0; num < count; ++num) {
1994 int ret;
1995 enum ffs_os_desc_type type;
1996 u16 feature_count;
1997 struct usb_os_desc_header *desc = (void *)data;
1998
1999 if (len < sizeof(*desc))
2000 return -EINVAL;
2001
2002 /*
2003 * Record "descriptor" entity.
2004 * Process dwLength, bcdVersion, wIndex, get b/wCount.
2005 * Move the data pointer to the beginning of extended
2006 * compatibilities proper or extended properties proper
2007 * portions of the data
2008 */
2009 if (le32_to_cpu(desc->dwLength) > len)
2010 return -EINVAL;
2011
2012 ret = __ffs_do_os_desc_header(&type, desc);
2013 if (unlikely(ret < 0)) {
2014 pr_debug("entity OS_DESCRIPTOR(%02lx); ret = %d\n",
2015 num, ret);
2016 return ret;
2017 }
2018 /*
2019 * 16-bit hex "?? 00" Little Endian looks like 8-bit hex "??"
2020 */
2021 feature_count = le16_to_cpu(desc->wCount);
2022 if (type == FFS_OS_DESC_EXT_COMPAT &&
2023 (feature_count > 255 || desc->Reserved))
2024 return -EINVAL;
2025 len -= ret;
2026 data += ret;
2027
2028 /*
2029 * Process all function/property descriptors
2030 * of this Feature Descriptor
2031 */
2032 ret = ffs_do_single_os_desc(data, len, type,
2033 feature_count, entity, priv, desc);
2034 if (unlikely(ret < 0)) {
2035 pr_debug("%s returns %d\n", __func__, ret);
2036 return ret;
2037 }
2038
2039 len -= ret;
2040 data += ret;
2041 }
2042 return _len - len;
2043 }
2044
2045 /**
2046 * Validate contents of the buffer from userspace related to OS descriptors.
2047 */
2048 static int __ffs_data_do_os_desc(enum ffs_os_desc_type type,
2049 struct usb_os_desc_header *h, void *data,
2050 unsigned len, void *priv)
2051 {
2052 struct ffs_data *ffs = priv;
2053 u8 length;
2054
2055 ENTER();
2056
2057 switch (type) {
2058 case FFS_OS_DESC_EXT_COMPAT: {
2059 struct usb_ext_compat_desc *d = data;
2060 int i;
2061
2062 if (len < sizeof(*d) ||
2063 d->bFirstInterfaceNumber >= ffs->interfaces_count ||
2064 d->Reserved1)
2065 return -EINVAL;
2066 for (i = 0; i < ARRAY_SIZE(d->Reserved2); ++i)
2067 if (d->Reserved2[i])
2068 return -EINVAL;
2069
2070 length = sizeof(struct usb_ext_compat_desc);
2071 }
2072 break;
2073 case FFS_OS_DESC_EXT_PROP: {
2074 struct usb_ext_prop_desc *d = data;
2075 u32 type, pdl;
2076 u16 pnl;
2077
2078 if (len < sizeof(*d) || h->interface >= ffs->interfaces_count)
2079 return -EINVAL;
2080 length = le32_to_cpu(d->dwSize);
2081 type = le32_to_cpu(d->dwPropertyDataType);
2082 if (type < USB_EXT_PROP_UNICODE ||
2083 type > USB_EXT_PROP_UNICODE_MULTI) {
2084 pr_vdebug("unsupported os descriptor property type: %d",
2085 type);
2086 return -EINVAL;
2087 }
2088 pnl = le16_to_cpu(d->wPropertyNameLength);
2089 pdl = le32_to_cpu(*(u32 *)((u8 *)data + 10 + pnl));
2090 if (length != 14 + pnl + pdl) {
2091 pr_vdebug("invalid os descriptor length: %d pnl:%d pdl:%d (descriptor %d)\n",
2092 length, pnl, pdl, type);
2093 return -EINVAL;
2094 }
2095 ++ffs->ms_os_descs_ext_prop_count;
2096 /* property name reported to the host as "WCHAR"s */
2097 ffs->ms_os_descs_ext_prop_name_len += pnl * 2;
2098 ffs->ms_os_descs_ext_prop_data_len += pdl;
2099 }
2100 break;
2101 default:
2102 pr_vdebug("unknown descriptor: %d\n", type);
2103 return -EINVAL;
2104 }
2105 return length;
2106 }
2107
2108 static int __ffs_data_got_descs(struct ffs_data *ffs,
2109 char *const _data, size_t len)
2110 {
2111 char *data = _data, *raw_descs;
2112 unsigned os_descs_count = 0, counts[3], flags;
2113 int ret = -EINVAL, i;
2114 struct ffs_desc_helper helper;
2115
2116 ENTER();
2117
2118 if (get_unaligned_le32(data + 4) != len)
2119 goto error;
2120
2121 switch (get_unaligned_le32(data)) {
2122 case FUNCTIONFS_DESCRIPTORS_MAGIC:
2123 flags = FUNCTIONFS_HAS_FS_DESC | FUNCTIONFS_HAS_HS_DESC;
2124 data += 8;
2125 len -= 8;
2126 break;
2127 case FUNCTIONFS_DESCRIPTORS_MAGIC_V2:
2128 flags = get_unaligned_le32(data + 8);
2129 ffs->user_flags = flags;
2130 if (flags & ~(FUNCTIONFS_HAS_FS_DESC |
2131 FUNCTIONFS_HAS_HS_DESC |
2132 FUNCTIONFS_HAS_SS_DESC |
2133 FUNCTIONFS_HAS_MS_OS_DESC |
2134 FUNCTIONFS_VIRTUAL_ADDR |
2135 FUNCTIONFS_EVENTFD)) {
2136 ret = -ENOSYS;
2137 goto error;
2138 }
2139 data += 12;
2140 len -= 12;
2141 break;
2142 default:
2143 goto error;
2144 }
2145
2146 if (flags & FUNCTIONFS_EVENTFD) {
2147 if (len < 4)
2148 goto error;
2149 ffs->ffs_eventfd =
2150 eventfd_ctx_fdget((int)get_unaligned_le32(data));
2151 if (IS_ERR(ffs->ffs_eventfd)) {
2152 ret = PTR_ERR(ffs->ffs_eventfd);
2153 ffs->ffs_eventfd = NULL;
2154 goto error;
2155 }
2156 data += 4;
2157 len -= 4;
2158 }
2159
2160 /* Read fs_count, hs_count and ss_count (if present) */
2161 for (i = 0; i < 3; ++i) {
2162 if (!(flags & (1 << i))) {
2163 counts[i] = 0;
2164 } else if (len < 4) {
2165 goto error;
2166 } else {
2167 counts[i] = get_unaligned_le32(data);
2168 data += 4;
2169 len -= 4;
2170 }
2171 }
2172 if (flags & (1 << i)) {
2173 os_descs_count = get_unaligned_le32(data);
2174 data += 4;
2175 len -= 4;
2176 };
2177
2178 /* Read descriptors */
2179 raw_descs = data;
2180 helper.ffs = ffs;
2181 for (i = 0; i < 3; ++i) {
2182 if (!counts[i])
2183 continue;
2184 helper.interfaces_count = 0;
2185 helper.eps_count = 0;
2186 ret = ffs_do_descs(counts[i], data, len,
2187 __ffs_data_do_entity, &helper);
2188 if (ret < 0)
2189 goto error;
2190 if (!ffs->eps_count && !ffs->interfaces_count) {
2191 ffs->eps_count = helper.eps_count;
2192 ffs->interfaces_count = helper.interfaces_count;
2193 } else {
2194 if (ffs->eps_count != helper.eps_count) {
2195 ret = -EINVAL;
2196 goto error;
2197 }
2198 if (ffs->interfaces_count != helper.interfaces_count) {
2199 ret = -EINVAL;
2200 goto error;
2201 }
2202 }
2203 data += ret;
2204 len -= ret;
2205 }
2206 if (os_descs_count) {
2207 ret = ffs_do_os_descs(os_descs_count, data, len,
2208 __ffs_data_do_os_desc, ffs);
2209 if (ret < 0)
2210 goto error;
2211 data += ret;
2212 len -= ret;
2213 }
2214
2215 if (raw_descs == data || len) {
2216 ret = -EINVAL;
2217 goto error;
2218 }
2219
2220 ffs->raw_descs_data = _data;
2221 ffs->raw_descs = raw_descs;
2222 ffs->raw_descs_length = data - raw_descs;
2223 ffs->fs_descs_count = counts[0];
2224 ffs->hs_descs_count = counts[1];
2225 ffs->ss_descs_count = counts[2];
2226 ffs->ms_os_descs_count = os_descs_count;
2227
2228 return 0;
2229
2230 error:
2231 kfree(_data);
2232 return ret;
2233 }
2234
2235 static int __ffs_data_got_strings(struct ffs_data *ffs,
2236 char *const _data, size_t len)
2237 {
2238 u32 str_count, needed_count, lang_count;
2239 struct usb_gadget_strings **stringtabs, *t;
2240 struct usb_string *strings, *s;
2241 const char *data = _data;
2242
2243 ENTER();
2244
2245 if (unlikely(get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
2246 get_unaligned_le32(data + 4) != len))
2247 goto error;
2248 str_count = get_unaligned_le32(data + 8);
2249 lang_count = get_unaligned_le32(data + 12);
2250
2251 /* if one is zero the other must be zero */
2252 if (unlikely(!str_count != !lang_count))
2253 goto error;
2254
2255 /* Do we have at least as many strings as descriptors need? */
2256 needed_count = ffs->strings_count;
2257 if (unlikely(str_count < needed_count))
2258 goto error;
2259
2260 /*
2261 * If we don't need any strings just return and free all
2262 * memory.
2263 */
2264 if (!needed_count) {
2265 kfree(_data);
2266 return 0;
2267 }
2268
2269 /* Allocate everything in one chunk so there's less maintenance. */
2270 {
2271 unsigned i = 0;
2272 vla_group(d);
2273 vla_item(d, struct usb_gadget_strings *, stringtabs,
2274 lang_count + 1);
2275 vla_item(d, struct usb_gadget_strings, stringtab, lang_count);
2276 vla_item(d, struct usb_string, strings,
2277 lang_count*(needed_count+1));
2278
2279 char *vlabuf = kmalloc(vla_group_size(d), GFP_KERNEL);
2280
2281 if (unlikely(!vlabuf)) {
2282 kfree(_data);
2283 return -ENOMEM;
2284 }
2285
2286 /* Initialize the VLA pointers */
2287 stringtabs = vla_ptr(vlabuf, d, stringtabs);
2288 t = vla_ptr(vlabuf, d, stringtab);
2289 i = lang_count;
2290 do {
2291 *stringtabs++ = t++;
2292 } while (--i);
2293 *stringtabs = NULL;
2294
2295 /* stringtabs = vlabuf = d_stringtabs for later kfree */
2296 stringtabs = vla_ptr(vlabuf, d, stringtabs);
2297 t = vla_ptr(vlabuf, d, stringtab);
2298 s = vla_ptr(vlabuf, d, strings);
2299 strings = s;
2300 }
2301
2302 /* For each language */
2303 data += 16;
2304 len -= 16;
2305
2306 do { /* lang_count > 0 so we can use do-while */
2307 unsigned needed = needed_count;
2308
2309 if (unlikely(len < 3))
2310 goto error_free;
2311 t->language = get_unaligned_le16(data);
2312 t->strings = s;
2313 ++t;
2314
2315 data += 2;
2316 len -= 2;
2317
2318 /* For each string */
2319 do { /* str_count > 0 so we can use do-while */
2320 size_t length = strnlen(data, len);
2321
2322 if (unlikely(length == len))
2323 goto error_free;
2324
2325 /*
2326 * User may provide more strings then we need,
2327 * if that's the case we simply ignore the
2328 * rest
2329 */
2330 if (likely(needed)) {
2331 /*
2332 * s->id will be set while adding
2333 * function to configuration so for
2334 * now just leave garbage here.
2335 */
2336 s->s = data;
2337 --needed;
2338 ++s;
2339 }
2340
2341 data += length + 1;
2342 len -= length + 1;
2343 } while (--str_count);
2344
2345 s->id = 0; /* terminator */
2346 s->s = NULL;
2347 ++s;
2348
2349 } while (--lang_count);
2350
2351 /* Some garbage left? */
2352 if (unlikely(len))
2353 goto error_free;
2354
2355 /* Done! */
2356 ffs->stringtabs = stringtabs;
2357 ffs->raw_strings = _data;
2358
2359 return 0;
2360
2361 error_free:
2362 kfree(stringtabs);
2363 error:
2364 kfree(_data);
2365 return -EINVAL;
2366 }
2367
2368
2369 /* Events handling and management *******************************************/
2370
2371 static void __ffs_event_add(struct ffs_data *ffs,
2372 enum usb_functionfs_event_type type)
2373 {
2374 enum usb_functionfs_event_type rem_type1, rem_type2 = type;
2375 int neg = 0;
2376
2377 /*
2378 * Abort any unhandled setup
2379 *
2380 * We do not need to worry about some cmpxchg() changing value
2381 * of ffs->setup_state without holding the lock because when
2382 * state is FFS_SETUP_PENDING cmpxchg() in several places in
2383 * the source does nothing.
2384 */
2385 if (ffs->setup_state == FFS_SETUP_PENDING)
2386 ffs->setup_state = FFS_SETUP_CANCELLED;
2387
2388 /*
2389 * Logic of this function guarantees that there are at most four pending
2390 * evens on ffs->ev.types queue. This is important because the queue
2391 * has space for four elements only and __ffs_ep0_read_events function
2392 * depends on that limit as well. If more event types are added, those
2393 * limits have to be revisited or guaranteed to still hold.
2394 */
2395 switch (type) {
2396 case FUNCTIONFS_RESUME:
2397 rem_type2 = FUNCTIONFS_SUSPEND;
2398 /* FALL THROUGH */
2399 case FUNCTIONFS_SUSPEND:
2400 case FUNCTIONFS_SETUP:
2401 rem_type1 = type;
2402 /* Discard all similar events */
2403 break;
2404
2405 case FUNCTIONFS_BIND:
2406 case FUNCTIONFS_UNBIND:
2407 case FUNCTIONFS_DISABLE:
2408 case FUNCTIONFS_ENABLE:
2409 /* Discard everything other then power management. */
2410 rem_type1 = FUNCTIONFS_SUSPEND;
2411 rem_type2 = FUNCTIONFS_RESUME;
2412 neg = 1;
2413 break;
2414
2415 default:
2416 WARN(1, "%d: unknown event, this should not happen\n", type);
2417 return;
2418 }
2419
2420 {
2421 u8 *ev = ffs->ev.types, *out = ev;
2422 unsigned n = ffs->ev.count;
2423 for (; n; --n, ++ev)
2424 if ((*ev == rem_type1 || *ev == rem_type2) == neg)
2425 *out++ = *ev;
2426 else
2427 pr_vdebug("purging event %d\n", *ev);
2428 ffs->ev.count = out - ffs->ev.types;
2429 }
2430
2431 pr_vdebug("adding event %d\n", type);
2432 ffs->ev.types[ffs->ev.count++] = type;
2433 wake_up_locked(&ffs->ev.waitq);
2434 if (ffs->ffs_eventfd)
2435 eventfd_signal(ffs->ffs_eventfd, 1);
2436 }
2437
2438 static void ffs_event_add(struct ffs_data *ffs,
2439 enum usb_functionfs_event_type type)
2440 {
2441 unsigned long flags;
2442 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2443 __ffs_event_add(ffs, type);
2444 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2445 }
2446
2447 /* Bind/unbind USB function hooks *******************************************/
2448
2449 static int ffs_ep_addr2idx(struct ffs_data *ffs, u8 endpoint_address)
2450 {
2451 int i;
2452
2453 for (i = 1; i < ARRAY_SIZE(ffs->eps_addrmap); ++i)
2454 if (ffs->eps_addrmap[i] == endpoint_address)
2455 return i;
2456 return -ENOENT;
2457 }
2458
2459 static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
2460 struct usb_descriptor_header *desc,
2461 void *priv)
2462 {
2463 struct usb_endpoint_descriptor *ds = (void *)desc;
2464 struct ffs_function *func = priv;
2465 struct ffs_ep *ffs_ep;
2466 unsigned ep_desc_id;
2467 int idx;
2468 static const char *speed_names[] = { "full", "high", "super" };
2469
2470 if (type != FFS_DESCRIPTOR)
2471 return 0;
2472
2473 /*
2474 * If ss_descriptors is not NULL, we are reading super speed
2475 * descriptors; if hs_descriptors is not NULL, we are reading high
2476 * speed descriptors; otherwise, we are reading full speed
2477 * descriptors.
2478 */
2479 if (func->function.ss_descriptors) {
2480 ep_desc_id = 2;
2481 func->function.ss_descriptors[(long)valuep] = desc;
2482 } else if (func->function.hs_descriptors) {
2483 ep_desc_id = 1;
2484 func->function.hs_descriptors[(long)valuep] = desc;
2485 } else {
2486 ep_desc_id = 0;
2487 func->function.fs_descriptors[(long)valuep] = desc;
2488 }
2489
2490 if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT)
2491 return 0;
2492
2493 idx = ffs_ep_addr2idx(func->ffs, ds->bEndpointAddress) - 1;
2494 if (idx < 0)
2495 return idx;
2496
2497 ffs_ep = func->eps + idx;
2498
2499 if (unlikely(ffs_ep->descs[ep_desc_id])) {
2500 pr_err("two %sspeed descriptors for EP %d\n",
2501 speed_names[ep_desc_id],
2502 ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
2503 return -EINVAL;
2504 }
2505 ffs_ep->descs[ep_desc_id] = ds;
2506
2507 ffs_dump_mem(": Original ep desc", ds, ds->bLength);
2508 if (ffs_ep->ep) {
2509 ds->bEndpointAddress = ffs_ep->descs[0]->bEndpointAddress;
2510 if (!ds->wMaxPacketSize)
2511 ds->wMaxPacketSize = ffs_ep->descs[0]->wMaxPacketSize;
2512 } else {
2513 struct usb_request *req;
2514 struct usb_ep *ep;
2515 u8 bEndpointAddress;
2516
2517 /*
2518 * We back up bEndpointAddress because autoconfig overwrites
2519 * it with physical endpoint address.
2520 */
2521 bEndpointAddress = ds->bEndpointAddress;
2522 pr_vdebug("autoconfig\n");
2523 ep = usb_ep_autoconfig(func->gadget, ds);
2524 if (unlikely(!ep))
2525 return -ENOTSUPP;
2526 ep->driver_data = func->eps + idx;
2527
2528 req = usb_ep_alloc_request(ep, GFP_KERNEL);
2529 if (unlikely(!req))
2530 return -ENOMEM;
2531
2532 ffs_ep->ep = ep;
2533 ffs_ep->req = req;
2534 func->eps_revmap[ds->bEndpointAddress &
2535 USB_ENDPOINT_NUMBER_MASK] = idx + 1;
2536 /*
2537 * If we use virtual address mapping, we restore
2538 * original bEndpointAddress value.
2539 */
2540 if (func->ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
2541 ds->bEndpointAddress = bEndpointAddress;
2542 }
2543 ffs_dump_mem(": Rewritten ep desc", ds, ds->bLength);
2544
2545 return 0;
2546 }
2547
2548 static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
2549 struct usb_descriptor_header *desc,
2550 void *priv)
2551 {
2552 struct ffs_function *func = priv;
2553 unsigned idx;
2554 u8 newValue;
2555
2556 switch (type) {
2557 default:
2558 case FFS_DESCRIPTOR:
2559 /* Handled in previous pass by __ffs_func_bind_do_descs() */
2560 return 0;
2561
2562 case FFS_INTERFACE:
2563 idx = *valuep;
2564 if (func->interfaces_nums[idx] < 0) {
2565 int id = usb_interface_id(func->conf, &func->function);
2566 if (unlikely(id < 0))
2567 return id;
2568 func->interfaces_nums[idx] = id;
2569 }
2570 newValue = func->interfaces_nums[idx];
2571 break;
2572
2573 case FFS_STRING:
2574 /* String' IDs are allocated when fsf_data is bound to cdev */
2575 newValue = func->ffs->stringtabs[0]->strings[*valuep - 1].id;
2576 break;
2577
2578 case FFS_ENDPOINT:
2579 /*
2580 * USB_DT_ENDPOINT are handled in
2581 * __ffs_func_bind_do_descs().
2582 */
2583 if (desc->bDescriptorType == USB_DT_ENDPOINT)
2584 return 0;
2585
2586 idx = (*valuep & USB_ENDPOINT_NUMBER_MASK) - 1;
2587 if (unlikely(!func->eps[idx].ep))
2588 return -EINVAL;
2589
2590 {
2591 struct usb_endpoint_descriptor **descs;
2592 descs = func->eps[idx].descs;
2593 newValue = descs[descs[0] ? 0 : 1]->bEndpointAddress;
2594 }
2595 break;
2596 }
2597
2598 pr_vdebug("%02x -> %02x\n", *valuep, newValue);
2599 *valuep = newValue;
2600 return 0;
2601 }
2602
2603 static int __ffs_func_bind_do_os_desc(enum ffs_os_desc_type type,
2604 struct usb_os_desc_header *h, void *data,
2605 unsigned len, void *priv)
2606 {
2607 struct ffs_function *func = priv;
2608 u8 length = 0;
2609
2610 switch (type) {
2611 case FFS_OS_DESC_EXT_COMPAT: {
2612 struct usb_ext_compat_desc *desc = data;
2613 struct usb_os_desc_table *t;
2614
2615 t = &func->function.os_desc_table[desc->bFirstInterfaceNumber];
2616 t->if_id = func->interfaces_nums[desc->bFirstInterfaceNumber];
2617 memcpy(t->os_desc->ext_compat_id, &desc->CompatibleID,
2618 ARRAY_SIZE(desc->CompatibleID) +
2619 ARRAY_SIZE(desc->SubCompatibleID));
2620 length = sizeof(*desc);
2621 }
2622 break;
2623 case FFS_OS_DESC_EXT_PROP: {
2624 struct usb_ext_prop_desc *desc = data;
2625 struct usb_os_desc_table *t;
2626 struct usb_os_desc_ext_prop *ext_prop;
2627 char *ext_prop_name;
2628 char *ext_prop_data;
2629
2630 t = &func->function.os_desc_table[h->interface];
2631 t->if_id = func->interfaces_nums[h->interface];
2632
2633 ext_prop = func->ffs->ms_os_descs_ext_prop_avail;
2634 func->ffs->ms_os_descs_ext_prop_avail += sizeof(*ext_prop);
2635
2636 ext_prop->type = le32_to_cpu(desc->dwPropertyDataType);
2637 ext_prop->name_len = le16_to_cpu(desc->wPropertyNameLength);
2638 ext_prop->data_len = le32_to_cpu(*(u32 *)
2639 usb_ext_prop_data_len_ptr(data, ext_prop->name_len));
2640 length = ext_prop->name_len + ext_prop->data_len + 14;
2641
2642 ext_prop_name = func->ffs->ms_os_descs_ext_prop_name_avail;
2643 func->ffs->ms_os_descs_ext_prop_name_avail +=
2644 ext_prop->name_len;
2645
2646 ext_prop_data = func->ffs->ms_os_descs_ext_prop_data_avail;
2647 func->ffs->ms_os_descs_ext_prop_data_avail +=
2648 ext_prop->data_len;
2649 memcpy(ext_prop_data,
2650 usb_ext_prop_data_ptr(data, ext_prop->name_len),
2651 ext_prop->data_len);
2652 /* unicode data reported to the host as "WCHAR"s */
2653 switch (ext_prop->type) {
2654 case USB_EXT_PROP_UNICODE:
2655 case USB_EXT_PROP_UNICODE_ENV:
2656 case USB_EXT_PROP_UNICODE_LINK:
2657 case USB_EXT_PROP_UNICODE_MULTI:
2658 ext_prop->data_len *= 2;
2659 break;
2660 }
2661 ext_prop->data = ext_prop_data;
2662
2663 memcpy(ext_prop_name, usb_ext_prop_name_ptr(data),
2664 ext_prop->name_len);
2665 /* property name reported to the host as "WCHAR"s */
2666 ext_prop->name_len *= 2;
2667 ext_prop->name = ext_prop_name;
2668
2669 t->os_desc->ext_prop_len +=
2670 ext_prop->name_len + ext_prop->data_len + 14;
2671 ++t->os_desc->ext_prop_count;
2672 list_add_tail(&ext_prop->entry, &t->os_desc->ext_prop);
2673 }
2674 break;
2675 default:
2676 pr_vdebug("unknown descriptor: %d\n", type);
2677 }
2678
2679 return length;
2680 }
2681
2682 static inline struct f_fs_opts *ffs_do_functionfs_bind(struct usb_function *f,
2683 struct usb_configuration *c)
2684 {
2685 struct ffs_function *func = ffs_func_from_usb(f);
2686 struct f_fs_opts *ffs_opts =
2687 container_of(f->fi, struct f_fs_opts, func_inst);
2688 int ret;
2689
2690 ENTER();
2691
2692 /*
2693 * Legacy gadget triggers binding in functionfs_ready_callback,
2694 * which already uses locking; taking the same lock here would
2695 * cause a deadlock.
2696 *
2697 * Configfs-enabled gadgets however do need ffs_dev_lock.
2698 */
2699 if (!ffs_opts->no_configfs)
2700 ffs_dev_lock();
2701 ret = ffs_opts->dev->desc_ready ? 0 : -ENODEV;
2702 func->ffs = ffs_opts->dev->ffs_data;
2703 if (!ffs_opts->no_configfs)
2704 ffs_dev_unlock();
2705 if (ret)
2706 return ERR_PTR(ret);
2707
2708 func->conf = c;
2709 func->gadget = c->cdev->gadget;
2710
2711 /*
2712 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
2713 * configurations are bound in sequence with list_for_each_entry,
2714 * in each configuration its functions are bound in sequence
2715 * with list_for_each_entry, so we assume no race condition
2716 * with regard to ffs_opts->bound access
2717 */
2718 if (!ffs_opts->refcnt) {
2719 ret = functionfs_bind(func->ffs, c->cdev);
2720 if (ret)
2721 return ERR_PTR(ret);
2722 }
2723 ffs_opts->refcnt++;
2724 func->function.strings = func->ffs->stringtabs;
2725
2726 return ffs_opts;
2727 }
2728
2729 static int _ffs_func_bind(struct usb_configuration *c,
2730 struct usb_function *f)
2731 {
2732 struct ffs_function *func = ffs_func_from_usb(f);
2733 struct ffs_data *ffs = func->ffs;
2734
2735 const int full = !!func->ffs->fs_descs_count;
2736 const int high = gadget_is_dualspeed(func->gadget) &&
2737 func->ffs->hs_descs_count;
2738 const int super = gadget_is_superspeed(func->gadget) &&
2739 func->ffs->ss_descs_count;
2740
2741 int fs_len, hs_len, ss_len, ret, i;
2742
2743 /* Make it a single chunk, less management later on */
2744 vla_group(d);
2745 vla_item_with_sz(d, struct ffs_ep, eps, ffs->eps_count);
2746 vla_item_with_sz(d, struct usb_descriptor_header *, fs_descs,
2747 full ? ffs->fs_descs_count + 1 : 0);
2748 vla_item_with_sz(d, struct usb_descriptor_header *, hs_descs,
2749 high ? ffs->hs_descs_count + 1 : 0);
2750 vla_item_with_sz(d, struct usb_descriptor_header *, ss_descs,
2751 super ? ffs->ss_descs_count + 1 : 0);
2752 vla_item_with_sz(d, short, inums, ffs->interfaces_count);
2753 vla_item_with_sz(d, struct usb_os_desc_table, os_desc_table,
2754 c->cdev->use_os_string ? ffs->interfaces_count : 0);
2755 vla_item_with_sz(d, char[16], ext_compat,
2756 c->cdev->use_os_string ? ffs->interfaces_count : 0);
2757 vla_item_with_sz(d, struct usb_os_desc, os_desc,
2758 c->cdev->use_os_string ? ffs->interfaces_count : 0);
2759 vla_item_with_sz(d, struct usb_os_desc_ext_prop, ext_prop,
2760 ffs->ms_os_descs_ext_prop_count);
2761 vla_item_with_sz(d, char, ext_prop_name,
2762 ffs->ms_os_descs_ext_prop_name_len);
2763 vla_item_with_sz(d, char, ext_prop_data,
2764 ffs->ms_os_descs_ext_prop_data_len);
2765 vla_item_with_sz(d, char, raw_descs, ffs->raw_descs_length);
2766 char *vlabuf;
2767
2768 ENTER();
2769
2770 /* Has descriptors only for speeds gadget does not support */
2771 if (unlikely(!(full | high | super)))
2772 return -ENOTSUPP;
2773
2774 /* Allocate a single chunk, less management later on */
2775 vlabuf = kzalloc(vla_group_size(d), GFP_KERNEL);
2776 if (unlikely(!vlabuf))
2777 return -ENOMEM;
2778
2779 ffs->ms_os_descs_ext_prop_avail = vla_ptr(vlabuf, d, ext_prop);
2780 ffs->ms_os_descs_ext_prop_name_avail =
2781 vla_ptr(vlabuf, d, ext_prop_name);
2782 ffs->ms_os_descs_ext_prop_data_avail =
2783 vla_ptr(vlabuf, d, ext_prop_data);
2784
2785 /* Copy descriptors */
2786 memcpy(vla_ptr(vlabuf, d, raw_descs), ffs->raw_descs,
2787 ffs->raw_descs_length);
2788
2789 memset(vla_ptr(vlabuf, d, inums), 0xff, d_inums__sz);
2790 for (ret = ffs->eps_count; ret; --ret) {
2791 struct ffs_ep *ptr;
2792
2793 ptr = vla_ptr(vlabuf, d, eps);
2794 ptr[ret].num = -1;
2795 }
2796
2797 /* Save pointers
2798 * d_eps == vlabuf, func->eps used to kfree vlabuf later
2799 */
2800 func->eps = vla_ptr(vlabuf, d, eps);
2801 func->interfaces_nums = vla_ptr(vlabuf, d, inums);
2802
2803 /*
2804 * Go through all the endpoint descriptors and allocate
2805 * endpoints first, so that later we can rewrite the endpoint
2806 * numbers without worrying that it may be described later on.
2807 */
2808 if (likely(full)) {
2809 func->function.fs_descriptors = vla_ptr(vlabuf, d, fs_descs);
2810 fs_len = ffs_do_descs(ffs->fs_descs_count,
2811 vla_ptr(vlabuf, d, raw_descs),
2812 d_raw_descs__sz,
2813 __ffs_func_bind_do_descs, func);
2814 if (unlikely(fs_len < 0)) {
2815 ret = fs_len;
2816 goto error;
2817 }
2818 } else {
2819 fs_len = 0;
2820 }
2821
2822 if (likely(high)) {
2823 func->function.hs_descriptors = vla_ptr(vlabuf, d, hs_descs);
2824 hs_len = ffs_do_descs(ffs->hs_descs_count,
2825 vla_ptr(vlabuf, d, raw_descs) + fs_len,
2826 d_raw_descs__sz - fs_len,
2827 __ffs_func_bind_do_descs, func);
2828 if (unlikely(hs_len < 0)) {
2829 ret = hs_len;
2830 goto error;
2831 }
2832 } else {
2833 hs_len = 0;
2834 }
2835
2836 if (likely(super)) {
2837 func->function.ss_descriptors = vla_ptr(vlabuf, d, ss_descs);
2838 ss_len = ffs_do_descs(ffs->ss_descs_count,
2839 vla_ptr(vlabuf, d, raw_descs) + fs_len + hs_len,
2840 d_raw_descs__sz - fs_len - hs_len,
2841 __ffs_func_bind_do_descs, func);
2842 if (unlikely(ss_len < 0)) {
2843 ret = ss_len;
2844 goto error;
2845 }
2846 } else {
2847 ss_len = 0;
2848 }
2849
2850 /*
2851 * Now handle interface numbers allocation and interface and
2852 * endpoint numbers rewriting. We can do that in one go
2853 * now.
2854 */
2855 ret = ffs_do_descs(ffs->fs_descs_count +
2856 (high ? ffs->hs_descs_count : 0) +
2857 (super ? ffs->ss_descs_count : 0),
2858 vla_ptr(vlabuf, d, raw_descs), d_raw_descs__sz,
2859 __ffs_func_bind_do_nums, func);
2860 if (unlikely(ret < 0))
2861 goto error;
2862
2863 func->function.os_desc_table = vla_ptr(vlabuf, d, os_desc_table);
2864 if (c->cdev->use_os_string)
2865 for (i = 0; i < ffs->interfaces_count; ++i) {
2866 struct usb_os_desc *desc;
2867
2868 desc = func->function.os_desc_table[i].os_desc =
2869 vla_ptr(vlabuf, d, os_desc) +
2870 i * sizeof(struct usb_os_desc);
2871 desc->ext_compat_id =
2872 vla_ptr(vlabuf, d, ext_compat) + i * 16;
2873 INIT_LIST_HEAD(&desc->ext_prop);
2874 }
2875 ret = ffs_do_os_descs(ffs->ms_os_descs_count,
2876 vla_ptr(vlabuf, d, raw_descs) +
2877 fs_len + hs_len + ss_len,
2878 d_raw_descs__sz - fs_len - hs_len - ss_len,
2879 __ffs_func_bind_do_os_desc, func);
2880 if (unlikely(ret < 0))
2881 goto error;
2882 func->function.os_desc_n =
2883 c->cdev->use_os_string ? ffs->interfaces_count : 0;
2884
2885 /* And we're done */
2886 ffs_event_add(ffs, FUNCTIONFS_BIND);
2887 return 0;
2888
2889 error:
2890 /* XXX Do we need to release all claimed endpoints here? */
2891 return ret;
2892 }
2893
2894 static int ffs_func_bind(struct usb_configuration *c,
2895 struct usb_function *f)
2896 {
2897 struct f_fs_opts *ffs_opts = ffs_do_functionfs_bind(f, c);
2898
2899 if (IS_ERR(ffs_opts))
2900 return PTR_ERR(ffs_opts);
2901
2902 return _ffs_func_bind(c, f);
2903 }
2904
2905
2906 /* Other USB function hooks *************************************************/
2907
2908 static void ffs_reset_work(struct work_struct *work)
2909 {
2910 struct ffs_data *ffs = container_of(work,
2911 struct ffs_data, reset_work);
2912 ffs_data_reset(ffs);
2913 }
2914
2915 static int ffs_func_set_alt(struct usb_function *f,
2916 unsigned interface, unsigned alt)
2917 {
2918 struct ffs_function *func = ffs_func_from_usb(f);
2919 struct ffs_data *ffs = func->ffs;
2920 int ret = 0, intf;
2921
2922 if (alt != (unsigned)-1) {
2923 intf = ffs_func_revmap_intf(func, interface);
2924 if (unlikely(intf < 0))
2925 return intf;
2926 }
2927
2928 if (ffs->func)
2929 ffs_func_eps_disable(ffs->func);
2930
2931 if (ffs->state == FFS_DEACTIVATED) {
2932 ffs->state = FFS_CLOSING;
2933 INIT_WORK(&ffs->reset_work, ffs_reset_work);
2934 schedule_work(&ffs->reset_work);
2935 return -ENODEV;
2936 }
2937
2938 if (ffs->state != FFS_ACTIVE)
2939 return -ENODEV;
2940
2941 if (alt == (unsigned)-1) {
2942 ffs->func = NULL;
2943 ffs_event_add(ffs, FUNCTIONFS_DISABLE);
2944 return 0;
2945 }
2946
2947 ffs->func = func;
2948 ret = ffs_func_eps_enable(func);
2949 if (likely(ret >= 0))
2950 ffs_event_add(ffs, FUNCTIONFS_ENABLE);
2951 return ret;
2952 }
2953
2954 static void ffs_func_disable(struct usb_function *f)
2955 {
2956 ffs_func_set_alt(f, 0, (unsigned)-1);
2957 }
2958
2959 static int ffs_func_setup(struct usb_function *f,
2960 const struct usb_ctrlrequest *creq)
2961 {
2962 struct ffs_function *func = ffs_func_from_usb(f);
2963 struct ffs_data *ffs = func->ffs;
2964 unsigned long flags;
2965 int ret;
2966
2967 ENTER();
2968
2969 pr_vdebug("creq->bRequestType = %02x\n", creq->bRequestType);
2970 pr_vdebug("creq->bRequest = %02x\n", creq->bRequest);
2971 pr_vdebug("creq->wValue = %04x\n", le16_to_cpu(creq->wValue));
2972 pr_vdebug("creq->wIndex = %04x\n", le16_to_cpu(creq->wIndex));
2973 pr_vdebug("creq->wLength = %04x\n", le16_to_cpu(creq->wLength));
2974
2975 /*
2976 * Most requests directed to interface go through here
2977 * (notable exceptions are set/get interface) so we need to
2978 * handle them. All other either handled by composite or
2979 * passed to usb_configuration->setup() (if one is set). No
2980 * matter, we will handle requests directed to endpoint here
2981 * as well (as it's straightforward) but what to do with any
2982 * other request?
2983 */
2984 if (ffs->state != FFS_ACTIVE)
2985 return -ENODEV;
2986
2987 switch (creq->bRequestType & USB_RECIP_MASK) {
2988 case USB_RECIP_INTERFACE:
2989 ret = ffs_func_revmap_intf(func, le16_to_cpu(creq->wIndex));
2990 if (unlikely(ret < 0))
2991 return ret;
2992 break;
2993
2994 case USB_RECIP_ENDPOINT:
2995 ret = ffs_func_revmap_ep(func, le16_to_cpu(creq->wIndex));
2996 if (unlikely(ret < 0))
2997 return ret;
2998 if (func->ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
2999 ret = func->ffs->eps_addrmap[ret];
3000 break;
3001
3002 default:
3003 return -EOPNOTSUPP;
3004 }
3005
3006 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
3007 ffs->ev.setup = *creq;
3008 ffs->ev.setup.wIndex = cpu_to_le16(ret);
3009 __ffs_event_add(ffs, FUNCTIONFS_SETUP);
3010 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
3011
3012 return 0;
3013 }
3014
3015 static void ffs_func_suspend(struct usb_function *f)
3016 {
3017 ENTER();
3018 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_SUSPEND);
3019 }
3020
3021 static void ffs_func_resume(struct usb_function *f)
3022 {
3023 ENTER();
3024 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_RESUME);
3025 }
3026
3027
3028 /* Endpoint and interface numbers reverse mapping ***************************/
3029
3030 static int ffs_func_revmap_ep(struct ffs_function *func, u8 num)
3031 {
3032 num = func->eps_revmap[num & USB_ENDPOINT_NUMBER_MASK];
3033 return num ? num : -EDOM;
3034 }
3035
3036 static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf)
3037 {
3038 short *nums = func->interfaces_nums;
3039 unsigned count = func->ffs->interfaces_count;
3040
3041 for (; count; --count, ++nums) {
3042 if (*nums >= 0 && *nums == intf)
3043 return nums - func->interfaces_nums;
3044 }
3045
3046 return -EDOM;
3047 }
3048
3049
3050 /* Devices management *******************************************************/
3051
3052 static LIST_HEAD(ffs_devices);
3053
3054 static struct ffs_dev *_ffs_do_find_dev(const char *name)
3055 {
3056 struct ffs_dev *dev;
3057
3058 list_for_each_entry(dev, &ffs_devices, entry) {
3059 if (!dev->name || !name)
3060 continue;
3061 if (strcmp(dev->name, name) == 0)
3062 return dev;
3063 }
3064
3065 return NULL;
3066 }
3067
3068 /*
3069 * ffs_lock must be taken by the caller of this function
3070 */
3071 static struct ffs_dev *_ffs_get_single_dev(void)
3072 {
3073 struct ffs_dev *dev;
3074
3075 if (list_is_singular(&ffs_devices)) {
3076 dev = list_first_entry(&ffs_devices, struct ffs_dev, entry);
3077 if (dev->single)
3078 return dev;
3079 }
3080
3081 return NULL;
3082 }
3083
3084 /*
3085 * ffs_lock must be taken by the caller of this function
3086 */
3087 static struct ffs_dev *_ffs_find_dev(const char *name)
3088 {
3089 struct ffs_dev *dev;
3090
3091 dev = _ffs_get_single_dev();
3092 if (dev)
3093 return dev;
3094
3095 return _ffs_do_find_dev(name);
3096 }
3097
3098 /* Configfs support *********************************************************/
3099
3100 static inline struct f_fs_opts *to_ffs_opts(struct config_item *item)
3101 {
3102 return container_of(to_config_group(item), struct f_fs_opts,
3103 func_inst.group);
3104 }
3105
3106 static void ffs_attr_release(struct config_item *item)
3107 {
3108 struct f_fs_opts *opts = to_ffs_opts(item);
3109
3110 usb_put_function_instance(&opts->func_inst);
3111 }
3112
3113 static struct configfs_item_operations ffs_item_ops = {
3114 .release = ffs_attr_release,
3115 };
3116
3117 static struct config_item_type ffs_func_type = {
3118 .ct_item_ops = &ffs_item_ops,
3119 .ct_owner = THIS_MODULE,
3120 };
3121
3122
3123 /* Function registration interface ******************************************/
3124
3125 static void ffs_free_inst(struct usb_function_instance *f)
3126 {
3127 struct f_fs_opts *opts;
3128
3129 opts = to_f_fs_opts(f);
3130 ffs_dev_lock();
3131 _ffs_free_dev(opts->dev);
3132 ffs_dev_unlock();
3133 kfree(opts);
3134 }
3135
3136 #define MAX_INST_NAME_LEN 40
3137
3138 static int ffs_set_inst_name(struct usb_function_instance *fi, const char *name)
3139 {
3140 struct f_fs_opts *opts;
3141 char *ptr;
3142 const char *tmp;
3143 int name_len, ret;
3144
3145 name_len = strlen(name) + 1;
3146 if (name_len > MAX_INST_NAME_LEN)
3147 return -ENAMETOOLONG;
3148
3149 ptr = kstrndup(name, name_len, GFP_KERNEL);
3150 if (!ptr)
3151 return -ENOMEM;
3152
3153 opts = to_f_fs_opts(fi);
3154 tmp = NULL;
3155
3156 ffs_dev_lock();
3157
3158 tmp = opts->dev->name_allocated ? opts->dev->name : NULL;
3159 ret = _ffs_name_dev(opts->dev, ptr);
3160 if (ret) {
3161 kfree(ptr);
3162 ffs_dev_unlock();
3163 return ret;
3164 }
3165 opts->dev->name_allocated = true;
3166
3167 ffs_dev_unlock();
3168
3169 kfree(tmp);
3170
3171 return 0;
3172 }
3173
3174 static struct usb_function_instance *ffs_alloc_inst(void)
3175 {
3176 struct f_fs_opts *opts;
3177 struct ffs_dev *dev;
3178
3179 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
3180 if (!opts)
3181 return ERR_PTR(-ENOMEM);
3182
3183 opts->func_inst.set_inst_name = ffs_set_inst_name;
3184 opts->func_inst.free_func_inst = ffs_free_inst;
3185 ffs_dev_lock();
3186 dev = _ffs_alloc_dev();
3187 ffs_dev_unlock();
3188 if (IS_ERR(dev)) {
3189 kfree(opts);
3190 return ERR_CAST(dev);
3191 }
3192 opts->dev = dev;
3193 dev->opts = opts;
3194
3195 config_group_init_type_name(&opts->func_inst.group, "",
3196 &ffs_func_type);
3197 return &opts->func_inst;
3198 }
3199
3200 static void ffs_free(struct usb_function *f)
3201 {
3202 kfree(ffs_func_from_usb(f));
3203 }
3204
3205 static void ffs_func_unbind(struct usb_configuration *c,
3206 struct usb_function *f)
3207 {
3208 struct ffs_function *func = ffs_func_from_usb(f);
3209 struct ffs_data *ffs = func->ffs;
3210 struct f_fs_opts *opts =
3211 container_of(f->fi, struct f_fs_opts, func_inst);
3212 struct ffs_ep *ep = func->eps;
3213 unsigned count = ffs->eps_count;
3214 unsigned long flags;
3215
3216 ENTER();
3217 if (ffs->func == func) {
3218 ffs_func_eps_disable(func);
3219 ffs->func = NULL;
3220 }
3221
3222 if (!--opts->refcnt)
3223 functionfs_unbind(ffs);
3224
3225 /* cleanup after autoconfig */
3226 spin_lock_irqsave(&func->ffs->eps_lock, flags);
3227 do {
3228 if (ep->ep && ep->req)
3229 usb_ep_free_request(ep->ep, ep->req);
3230 ep->req = NULL;
3231 ++ep;
3232 } while (--count);
3233 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
3234 kfree(func->eps);
3235 func->eps = NULL;
3236 /*
3237 * eps, descriptors and interfaces_nums are allocated in the
3238 * same chunk so only one free is required.
3239 */
3240 func->function.fs_descriptors = NULL;
3241 func->function.hs_descriptors = NULL;
3242 func->function.ss_descriptors = NULL;
3243 func->interfaces_nums = NULL;
3244
3245 ffs_event_add(ffs, FUNCTIONFS_UNBIND);
3246 }
3247
3248 static struct usb_function *ffs_alloc(struct usb_function_instance *fi)
3249 {
3250 struct ffs_function *func;
3251
3252 ENTER();
3253
3254 func = kzalloc(sizeof(*func), GFP_KERNEL);
3255 if (unlikely(!func))
3256 return ERR_PTR(-ENOMEM);
3257
3258 func->function.name = "Function FS Gadget";
3259
3260 func->function.bind = ffs_func_bind;
3261 func->function.unbind = ffs_func_unbind;
3262 func->function.set_alt = ffs_func_set_alt;
3263 func->function.disable = ffs_func_disable;
3264 func->function.setup = ffs_func_setup;
3265 func->function.suspend = ffs_func_suspend;
3266 func->function.resume = ffs_func_resume;
3267 func->function.free_func = ffs_free;
3268
3269 return &func->function;
3270 }
3271
3272 /*
3273 * ffs_lock must be taken by the caller of this function
3274 */
3275 static struct ffs_dev *_ffs_alloc_dev(void)
3276 {
3277 struct ffs_dev *dev;
3278 int ret;
3279
3280 if (_ffs_get_single_dev())
3281 return ERR_PTR(-EBUSY);
3282
3283 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
3284 if (!dev)
3285 return ERR_PTR(-ENOMEM);
3286
3287 if (list_empty(&ffs_devices)) {
3288 ret = functionfs_init();
3289 if (ret) {
3290 kfree(dev);
3291 return ERR_PTR(ret);
3292 }
3293 }
3294
3295 list_add(&dev->entry, &ffs_devices);
3296
3297 return dev;
3298 }
3299
3300 /*
3301 * ffs_lock must be taken by the caller of this function
3302 * The caller is responsible for "name" being available whenever f_fs needs it
3303 */
3304 static int _ffs_name_dev(struct ffs_dev *dev, const char *name)
3305 {
3306 struct ffs_dev *existing;
3307
3308 existing = _ffs_do_find_dev(name);
3309 if (existing)
3310 return -EBUSY;
3311
3312 dev->name = name;
3313
3314 return 0;
3315 }
3316
3317 /*
3318 * The caller is responsible for "name" being available whenever f_fs needs it
3319 */
3320 int ffs_name_dev(struct ffs_dev *dev, const char *name)
3321 {
3322 int ret;
3323
3324 ffs_dev_lock();
3325 ret = _ffs_name_dev(dev, name);
3326 ffs_dev_unlock();
3327
3328 return ret;
3329 }
3330 EXPORT_SYMBOL_GPL(ffs_name_dev);
3331
3332 int ffs_single_dev(struct ffs_dev *dev)
3333 {
3334 int ret;
3335
3336 ret = 0;
3337 ffs_dev_lock();
3338
3339 if (!list_is_singular(&ffs_devices))
3340 ret = -EBUSY;
3341 else
3342 dev->single = true;
3343
3344 ffs_dev_unlock();
3345 return ret;
3346 }
3347 EXPORT_SYMBOL_GPL(ffs_single_dev);
3348
3349 /*
3350 * ffs_lock must be taken by the caller of this function
3351 */
3352 static void _ffs_free_dev(struct ffs_dev *dev)
3353 {
3354 list_del(&dev->entry);
3355 if (dev->name_allocated)
3356 kfree(dev->name);
3357 kfree(dev);
3358 if (list_empty(&ffs_devices))
3359 functionfs_cleanup();
3360 }
3361
3362 static void *ffs_acquire_dev(const char *dev_name)
3363 {
3364 struct ffs_dev *ffs_dev;
3365
3366 ENTER();
3367 ffs_dev_lock();
3368
3369 ffs_dev = _ffs_find_dev(dev_name);
3370 if (!ffs_dev)
3371 ffs_dev = ERR_PTR(-ENOENT);
3372 else if (ffs_dev->mounted)
3373 ffs_dev = ERR_PTR(-EBUSY);
3374 else if (ffs_dev->ffs_acquire_dev_callback &&
3375 ffs_dev->ffs_acquire_dev_callback(ffs_dev))
3376 ffs_dev = ERR_PTR(-ENOENT);
3377 else
3378 ffs_dev->mounted = true;
3379
3380 ffs_dev_unlock();
3381 return ffs_dev;
3382 }
3383
3384 static void ffs_release_dev(struct ffs_data *ffs_data)
3385 {
3386 struct ffs_dev *ffs_dev;
3387
3388 ENTER();
3389 ffs_dev_lock();
3390
3391 ffs_dev = ffs_data->private_data;
3392 if (ffs_dev) {
3393 ffs_dev->mounted = false;
3394
3395 if (ffs_dev->ffs_release_dev_callback)
3396 ffs_dev->ffs_release_dev_callback(ffs_dev);
3397 }
3398
3399 ffs_dev_unlock();
3400 }
3401
3402 static int ffs_ready(struct ffs_data *ffs)
3403 {
3404 struct ffs_dev *ffs_obj;
3405 int ret = 0;
3406
3407 ENTER();
3408 ffs_dev_lock();
3409
3410 ffs_obj = ffs->private_data;
3411 if (!ffs_obj) {
3412 ret = -EINVAL;
3413 goto done;
3414 }
3415 if (WARN_ON(ffs_obj->desc_ready)) {
3416 ret = -EBUSY;
3417 goto done;
3418 }
3419
3420 ffs_obj->desc_ready = true;
3421 ffs_obj->ffs_data = ffs;
3422
3423 if (ffs_obj->ffs_ready_callback) {
3424 ret = ffs_obj->ffs_ready_callback(ffs);
3425 if (ret)
3426 goto done;
3427 }
3428
3429 set_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags);
3430 done:
3431 ffs_dev_unlock();
3432 return ret;
3433 }
3434
3435 static void ffs_closed(struct ffs_data *ffs)
3436 {
3437 struct ffs_dev *ffs_obj;
3438
3439 ENTER();
3440 ffs_dev_lock();
3441
3442 ffs_obj = ffs->private_data;
3443 if (!ffs_obj)
3444 goto done;
3445
3446 ffs_obj->desc_ready = false;
3447
3448 if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags) &&
3449 ffs_obj->ffs_closed_callback)
3450 ffs_obj->ffs_closed_callback(ffs);
3451
3452 if (!ffs_obj->opts || ffs_obj->opts->no_configfs
3453 || !ffs_obj->opts->func_inst.group.cg_item.ci_parent)
3454 goto done;
3455
3456 unregister_gadget_item(ffs_obj->opts->
3457 func_inst.group.cg_item.ci_parent->ci_parent);
3458 done:
3459 ffs_dev_unlock();
3460 }
3461
3462 /* Misc helper functions ****************************************************/
3463
3464 static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
3465 {
3466 return nonblock
3467 ? likely(mutex_trylock(mutex)) ? 0 : -EAGAIN
3468 : mutex_lock_interruptible(mutex);
3469 }
3470
3471 static char *ffs_prepare_buffer(const char __user *buf, size_t len)
3472 {
3473 char *data;
3474
3475 if (unlikely(!len))
3476 return NULL;
3477
3478 data = kmalloc(len, GFP_KERNEL);
3479 if (unlikely(!data))
3480 return ERR_PTR(-ENOMEM);
3481
3482 if (unlikely(__copy_from_user(data, buf, len))) {
3483 kfree(data);
3484 return ERR_PTR(-EFAULT);
3485 }
3486
3487 pr_vdebug("Buffer from user space:\n");
3488 ffs_dump_mem("", data, len);
3489
3490 return data;
3491 }
3492
3493 DECLARE_USB_FUNCTION_INIT(ffs, ffs_alloc_inst, ffs_alloc);
3494 MODULE_LICENSE("GPL");
3495 MODULE_AUTHOR("Michal Nazarewicz");
Linux with added FPC-III support