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fs: split generic and aio kiocb
[deliverable/linux.git] / drivers / usb / gadget / function / f_fs.c
CommitLineData
ddf8abd2 1/*
5ab54cf7 2 * f_fs.c -- user mode file system API for USB composite function controllers
ddf8abd2
MN		 3 *
4 * Copyright (C) 2010 Samsung Electronics
54b8360f 5 * Author: Michal Nazarewicz <mina86@mina86.com>
ddf8abd2 6 *
5ab54cf7 7 * Based on inode.c (GadgetFS) which was:
ddf8abd2
MN		 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.
ddf8abd2
MN		 15 */
16
17
18/* #define DEBUG */
19/* #define VERBOSE_DEBUG */
20
21#include <linux/blkdev.h>
b0608690 22#include <linux/pagemap.h>
f940fcd8 23#include <linux/export.h>
560f1187 24#include <linux/hid.h>
5920cda6 25#include <linux/module.h>
ddf8abd2 26#include <asm/unaligned.h>
ddf8abd2
MN		 27
28#include <linux/usb/composite.h>
29#include <linux/usb/functionfs.h>
30
2e4c7553
RB		 31#include <linux/aio.h>
32#include <linux/mmu_context.h>
23de91e9 33#include <linux/poll.h>
5e33f6fd 34#include <linux/eventfd.h>
23de91e9 35
e72c39c0 36#include "u_fs.h"
74d48466 37#include "u_f.h"
f0175ab5 38#include "u_os_desc.h"
b658499f 39#include "configfs.h"
ddf8abd2
MN		 40
41#define FUNCTIONFS_MAGIC 0xa647361 /* Chosen by a honest dice roll ;) */
42
ddf8abd2
MN		 43/* Reference counter handling */
44static void ffs_data_get(struct ffs_data *ffs);
45static void ffs_data_put(struct ffs_data *ffs);
46/* Creates new ffs_data object. */
47static struct ffs_data *__must_check ffs_data_new(void) __attribute__((malloc));
48
49/* Opened counter handling. */
50static void ffs_data_opened(struct ffs_data *ffs);
51static void ffs_data_closed(struct ffs_data *ffs);
52
5ab54cf7 53/* Called with ffs->mutex held; take over ownership of data. */
ddf8abd2
MN		 54static int __must_check
55__ffs_data_got_descs(struct ffs_data *ffs, char *data, size_t len);
56static int __must_check
57__ffs_data_got_strings(struct ffs_data *ffs, char *data, size_t len);
58
59
60/* The function structure ***************************************************/
61
62struct ffs_ep;
63
64struct ffs_function {
65 struct usb_configuration *conf;
66 struct usb_gadget *gadget;
67 struct ffs_data *ffs;
68
69 struct ffs_ep *eps;
70 u8 eps_revmap[16];
71 short *interfaces_nums;
72
73 struct usb_function function;
74};
75
76
77static struct ffs_function *ffs_func_from_usb(struct usb_function *f)
78{
79 return container_of(f, struct ffs_function, function);
80}
81
ddf8abd2 82
a7ecf054
MN		 83static inline enum ffs_setup_state
84ffs_setup_state_clear_cancelled(struct ffs_data *ffs)
85{
86 return (enum ffs_setup_state)
87 cmpxchg(&ffs->setup_state, FFS_SETUP_CANCELLED, FFS_NO_SETUP);
88}
89
90
ddf8abd2
MN		 91static void ffs_func_eps_disable(struct ffs_function *func);
92static int __must_check ffs_func_eps_enable(struct ffs_function *func);
93
ddf8abd2
MN		 94static int ffs_func_bind(struct usb_configuration *,
95 struct usb_function *);
ddf8abd2
MN		 96static int ffs_func_set_alt(struct usb_function *, unsigned, unsigned);
97static void ffs_func_disable(struct usb_function *);
98static int ffs_func_setup(struct usb_function *,
99 const struct usb_ctrlrequest *);
100static void ffs_func_suspend(struct usb_function *);
101static void ffs_func_resume(struct usb_function *);
102
103
104static int ffs_func_revmap_ep(struct ffs_function *func, u8 num);
105static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf);
106
107
ddf8abd2
MN		 108/* The endpoints structures *************************************************/
109
110struct ffs_ep {
111 struct usb_ep *ep; /* P: ffs->eps_lock */
112 struct usb_request *req; /* P: epfile->mutex */
113
8d4e897b
MG		 114 /* [0]: full speed, [1]: high speed, [2]: super speed */
115 struct usb_endpoint_descriptor *descs[3];
ddf8abd2
MN		 116
117 u8 num;
118
119 int status; /* P: epfile->mutex */
120};
121
122struct ffs_epfile {
123 /* Protects ep->ep and ep->req. */
124 struct mutex mutex;
125 wait_queue_head_t wait;
126
127 struct ffs_data *ffs;
128 struct ffs_ep *ep; /* P: ffs->eps_lock */
129
130 struct dentry *dentry;
131
132 char name[5];
133
134 unsigned char in; /* P: ffs->eps_lock */
135 unsigned char isoc; /* P: ffs->eps_lock */
136
137 unsigned char _pad;
138};
139
2e4c7553
RB		 140/* ffs_io_data structure ***************************************************/
141
142struct ffs_io_data {
143 bool aio;
144 bool read;
145
146 struct kiocb *kiocb;
c993c39b
AV		 147 struct iov_iter data;
148 const void *to_free;
149 char *buf;
2e4c7553
RB		 150
151 struct mm_struct *mm;
152 struct work_struct work;
153
154 struct usb_ep *ep;
155 struct usb_request *req;
5e33f6fd
RB		 156
157 struct ffs_data *ffs;
2e4c7553
RB		 158};
159
6d5c1c77
RB		 160struct ffs_desc_helper {
161 struct ffs_data *ffs;
162 unsigned interfaces_count;
163 unsigned eps_count;
164};
165
ddf8abd2
MN		 166static int __must_check ffs_epfiles_create(struct ffs_data *ffs);
167static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count);
168
1bb27cac 169static struct dentry *
ddf8abd2 170ffs_sb_create_file(struct super_block *sb, const char *name, void *data,
1bb27cac 171 const struct file_operations *fops);
ddf8abd2 172
4b187fce
AP		 173/* Devices management *******************************************************/
174
175DEFINE_MUTEX(ffs_lock);
0700faaf 176EXPORT_SYMBOL_GPL(ffs_lock);
4b187fce 177
da13a773
AP		 178static struct ffs_dev *_ffs_find_dev(const char *name);
179static struct ffs_dev *_ffs_alloc_dev(void);
b658499f 180static int _ffs_name_dev(struct ffs_dev *dev, const char *name);
da13a773 181static void _ffs_free_dev(struct ffs_dev *dev);
4b187fce
AP		 182static void *ffs_acquire_dev(const char *dev_name);
183static void ffs_release_dev(struct ffs_data *ffs_data);
184static int ffs_ready(struct ffs_data *ffs);
185static void ffs_closed(struct ffs_data *ffs);
ddf8abd2
MN		 186
187/* Misc helper functions ****************************************************/
188
189static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
190 __attribute__((warn_unused_result, nonnull));
260ef311 191static char *ffs_prepare_buffer(const char __user *buf, size_t len)
ddf8abd2
MN		 192 __attribute__((warn_unused_result, nonnull));
193
194
195/* Control file aka ep0 *****************************************************/
196
197static void ffs_ep0_complete(struct usb_ep *ep, struct usb_request *req)
198{
199 struct ffs_data *ffs = req->context;
200
201 complete_all(&ffs->ep0req_completion);
202}
203
ddf8abd2
MN		 204static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
205{
206 struct usb_request *req = ffs->ep0req;
207 int ret;
208
209 req->zero = len < le16_to_cpu(ffs->ev.setup.wLength);
210
211 spin_unlock_irq(&ffs->ev.waitq.lock);
212
213 req->buf = data;
214 req->length = len;
215
ce1fd358
MS		 216 /*
217 * UDC layer requires to provide a buffer even for ZLP, but should
218 * not use it at all. Let's provide some poisoned pointer to catch
219 * possible bug in the driver.
220 */
221 if (req->buf == NULL)
222 req->buf = (void *)0xDEADBABE;
223
16735d02 224 reinit_completion(&ffs->ep0req_completion);
ddf8abd2
MN		 225
226 ret = usb_ep_queue(ffs->gadget->ep0, req, GFP_ATOMIC);
227 if (unlikely(ret < 0))
228 return ret;
229
230 ret = wait_for_completion_interruptible(&ffs->ep0req_completion);
231 if (unlikely(ret)) {
232 usb_ep_dequeue(ffs->gadget->ep0, req);
233 return -EINTR;
234 }
235
236 ffs->setup_state = FFS_NO_SETUP;
0a7b1f8a 237 return req->status ? req->status : req->actual;
ddf8abd2
MN		 238}
239
240static int __ffs_ep0_stall(struct ffs_data *ffs)
241{
242 if (ffs->ev.can_stall) {
aa02f172 243 pr_vdebug("ep0 stall\n");
ddf8abd2
MN		 244 usb_ep_set_halt(ffs->gadget->ep0);
245 ffs->setup_state = FFS_NO_SETUP;
246 return -EL2HLT;
247 } else {
aa02f172 248 pr_debug("bogus ep0 stall!\n");
ddf8abd2
MN		 249 return -ESRCH;
250 }
251}
252
ddf8abd2
MN		 253static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
254 size_t len, loff_t *ptr)
255{
256 struct ffs_data *ffs = file->private_data;
257 ssize_t ret;
258 char *data;
259
260 ENTER();
261
262 /* Fast check if setup was canceled */
a7ecf054 263 if (ffs_setup_state_clear_cancelled(ffs) == FFS_SETUP_CANCELLED)
ddf8abd2
MN		 264 return -EIDRM;
265
266 /* Acquire mutex */
267 ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
268 if (unlikely(ret < 0))
269 return ret;
270
ddf8abd2
MN		 271 /* Check state */
272 switch (ffs->state) {
273 case FFS_READ_DESCRIPTORS:
274 case FFS_READ_STRINGS:
275 /* Copy data */
276 if (unlikely(len < 16)) {
277 ret = -EINVAL;
278 break;
279 }
280
281 data = ffs_prepare_buffer(buf, len);
537baabb 282 if (IS_ERR(data)) {
ddf8abd2
MN		 283 ret = PTR_ERR(data);
284 break;
285 }
286
287 /* Handle data */
288 if (ffs->state == FFS_READ_DESCRIPTORS) {
aa02f172 289 pr_info("read descriptors\n");
ddf8abd2
MN		 290 ret = __ffs_data_got_descs(ffs, data, len);
291 if (unlikely(ret < 0))
292 break;
293
294 ffs->state = FFS_READ_STRINGS;
295 ret = len;
296 } else {
aa02f172 297 pr_info("read strings\n");
ddf8abd2
MN		 298 ret = __ffs_data_got_strings(ffs, data, len);
299 if (unlikely(ret < 0))
300 break;
301
302 ret = ffs_epfiles_create(ffs);
303 if (unlikely(ret)) {
304 ffs->state = FFS_CLOSING;
305 break;
306 }
307
308 ffs->state = FFS_ACTIVE;
309 mutex_unlock(&ffs->mutex);
310
4b187fce 311 ret = ffs_ready(ffs);
ddf8abd2
MN		 312 if (unlikely(ret < 0)) {
313 ffs->state = FFS_CLOSING;
314 return ret;
315 }
316
317 set_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags);
318 return len;
319 }
320 break;
321
ddf8abd2
MN		 322 case FFS_ACTIVE:
323 data = NULL;
5ab54cf7
MN		 324 /*
325 * We're called from user space, we can use _irq
326 * rather then _irqsave
327 */
ddf8abd2 328 spin_lock_irq(&ffs->ev.waitq.lock);
a7ecf054 329 switch (ffs_setup_state_clear_cancelled(ffs)) {
e46318a0 330 case FFS_SETUP_CANCELLED:
ddf8abd2
MN		 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);
537baabb 355 if (IS_ERR(data)) {
ddf8abd2
MN		 356 ret = PTR_ERR(data);
357 break;
358 }
359
360 spin_lock_irq(&ffs->ev.waitq.lock);
361
5ab54cf7
MN		 362 /*
363 * We are guaranteed to be still in FFS_ACTIVE state
ddf8abd2 364 * but the state of setup could have changed from
e46318a0 365 * FFS_SETUP_PENDING to FFS_SETUP_CANCELLED so we need
ddf8abd2 366 * to check for that. If that happened we copied data
5ab54cf7
MN		 367 * from user space in vain but it's unlikely.
368 *
369 * For sure we are not in FFS_NO_SETUP since this is
ddf8abd2
MN		 370 * the only place FFS_SETUP_PENDING -> FFS_NO_SETUP
371 * transition can be performed and it's protected by
5ab54cf7
MN		 372 * mutex.
373 */
a7ecf054
MN		 374 if (ffs_setup_state_clear_cancelled(ffs) ==
375 FFS_SETUP_CANCELLED) {
ddf8abd2
MN		 376 ret = -EIDRM;
377done_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
ddf8abd2
MN		 386 default:
387 ret = -EBADFD;
388 break;
389 }
390
ddf8abd2
MN		 391 mutex_unlock(&ffs->mutex);
392 return ret;
393}
394
67913bbd 395/* Called with ffs->ev.waitq.lock and ffs->mutex held, both released on exit. */
ddf8abd2
MN		 396static ssize_t __ffs_ep0_read_events(struct ffs_data *ffs, char __user *buf,
397 size_t n)
398{
5ab54cf7 399 /*
67913bbd
MN		 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.
5ab54cf7 403 */
67913bbd
MN		 404 struct usb_functionfs_event events[ARRAY_SIZE(ffs->ev.types)];
405 const size_t size = n * sizeof *events;
ddf8abd2
MN		 406 unsigned i = 0;
407
67913bbd 408 memset(events, 0, size);
ddf8abd2
MN		 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
67913bbd
MN		 418 ffs->ev.count -= n;
419 if (ffs->ev.count)
ddf8abd2
MN		 420 memmove(ffs->ev.types, ffs->ev.types + n,
421 ffs->ev.count * sizeof *ffs->ev.types);
ddf8abd2
MN		 422
423 spin_unlock_irq(&ffs->ev.waitq.lock);
424 mutex_unlock(&ffs->mutex);
425
67913bbd 426 return unlikely(__copy_to_user(buf, events, size)) ? -EFAULT : size;
ddf8abd2
MN		 427}
428
ddf8abd2
MN		 429static 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 */
a7ecf054 440 if (ffs_setup_state_clear_cancelled(ffs) == FFS_SETUP_CANCELLED)
ddf8abd2
MN		 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
ddf8abd2
MN		 448 /* Check state */
449 if (ffs->state != FFS_ACTIVE) {
450 ret = -EBADFD;
451 goto done_mutex;
452 }
453
5ab54cf7
MN		 454 /*
455 * We're called from user space, we can use _irq rather then
456 * _irqsave
457 */
ddf8abd2
MN		 458 spin_lock_irq(&ffs->ev.waitq.lock);
459
a7ecf054 460 switch (ffs_setup_state_clear_cancelled(ffs)) {
e46318a0 461 case FFS_SETUP_CANCELLED:
ddf8abd2
MN		 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
5ab54cf7
MN		 477 if (wait_event_interruptible_exclusive_locked_irq(ffs->ev.waitq,
478 ffs->ev.count)) {
ddf8abd2
MN		 479 ret = -EINTR;
480 break;
481 }
482
483 return __ffs_ep0_read_events(ffs, buf,
484 min(n, (size_t)ffs->ev.count));
485
ddf8abd2
MN		 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() */
a7ecf054
MN		 508 if (ffs_setup_state_clear_cancelled(ffs) ==
509 FFS_SETUP_CANCELLED) {
ddf8abd2
MN		 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);
526done_mutex:
527 mutex_unlock(&ffs->mutex);
528 kfree(data);
529 return ret;
530}
531
ddf8abd2
MN		 532static 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
ddf8abd2
MN		 547static 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
ddf8abd2
MN		 558static 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;
92b0abf8 569 } else if (gadget && gadget->ops->ioctl) {
ddf8abd2 570 ret = gadget->ops->ioctl(gadget, code, value);
ddf8abd2
MN		 571 } else {
572 ret = -ENOTTY;
573 }
574
575 return ret;
576}
577
23de91e9
RB		 578static 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;
18d6b32f
RB		 610 case FFS_DEACTIVATED:
611 break;
23de91e9
RB		 612 }
613
614 mutex_unlock(&ffs->mutex);
615
616 return mask;
617}
618
ddf8abd2 619static const struct file_operations ffs_ep0_operations = {
ddf8abd2
MN		 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,
23de91e9 627 .poll = ffs_ep0_poll,
ddf8abd2
MN		 628};
629
630
631/* "Normal" endpoints operations ********************************************/
632
ddf8abd2
MN		 633static 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
2e4c7553
RB		 643static 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) {
2e4c7553 651 use_mm(io_data->mm);
c993c39b
AV		 652 ret = copy_to_iter(io_data->buf, ret, &io_data->data);
653 if (iov_iter_count(&io_data->data))
654 ret = -EFAULT;
2e4c7553
RB		 655 unuse_mm(io_data->mm);
656 }
657
04b2fa9f 658 io_data->kiocb->ki_complete(io_data->kiocb, ret, ret);
2e4c7553 659
04b2fa9f
CH		 660 if (io_data->ffs->ffs_eventfd &&
661 !(io_data->kiocb->ki_flags & IOCB_EVENTFD))
5e33f6fd
RB		 662 eventfd_signal(io_data->ffs->ffs_eventfd, 1);
663
2e4c7553
RB		 664 usb_ep_free_request(io_data->ep, io_data->req);
665
666 io_data->kiocb->private = NULL;
667 if (io_data->read)
c993c39b 668 kfree(io_data->to_free);
2e4c7553
RB		 669 kfree(io_data->buf);
670 kfree(io_data);
671}
672
673static 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
684static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
ddf8abd2
MN		 685{
686 struct ffs_epfile *epfile = file->private_data;
687 struct ffs_ep *ep;
688 char *data = NULL;
c0d31b3c 689 ssize_t ret, data_len = -EINVAL;
ddf8abd2
MN		 690 int halt;
691
7fa68034
MN		 692 /* Are we still active? */
693 if (WARN_ON(epfile->ffs->state != FFS_ACTIVE)) {
694 ret = -ENODEV;
695 goto error;
696 }
ddf8abd2 697
7fa68034
MN		 698 /* Wait for endpoint to be enabled */
699 ep = epfile->ep;
700 if (!ep) {
701 if (file->f_flags & O_NONBLOCK) {
702 ret = -EAGAIN;
ddf8abd2
MN		 703 goto error;
704 }
705
7fa68034
MN		 706 ret = wait_event_interruptible(epfile->wait, (ep = epfile->ep));
707 if (ret) {
708 ret = -EINTR;
ddf8abd2
MN		 709 goto error;
710 }
7fa68034 711 }
ddf8abd2 712
7fa68034 713 /* Do we halt? */
2e4c7553 714 halt = (!io_data->read == !epfile->in);
7fa68034
MN		 715 if (halt && epfile->isoc) {
716 ret = -EINVAL;
717 goto error;
718 }
ddf8abd2 719
7fa68034
MN		 720 /* Allocate & copy */
721 if (!halt) {
f0f42204
AP		 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;
c993c39b 727 size_t copied;
f0f42204 728
97839ca4
CB		 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 }
c993c39b 735 data_len = iov_iter_count(&io_data->data);
219580e6
MN		 736 /*
737 * Controller may require buffer size to be aligned to
738 * maxpacketsize of an out endpoint.
739 */
c993c39b
AV		 740 if (io_data->read)
741 data_len = usb_ep_align_maybe(gadget, ep->ep, data_len);
97839ca4 742 spin_unlock_irq(&epfile->ffs->eps_lock);
219580e6
MN		 743
744 data = kmalloc(data_len, GFP_KERNEL);
7fa68034
MN		 745 if (unlikely(!data))
746 return -ENOMEM;
c993c39b
AV		 747 if (!io_data->read) {
748 copied = copy_from_iter(data, data_len, &io_data->data);
749 if (copied != data_len) {
2e4c7553
RB		 750 ret = -EFAULT;
751 goto error;
752 }
7fa68034
MN		 753 }
754 }
ddf8abd2 755
7fa68034
MN		 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;
ddf8abd2 760
7fa68034 761 spin_lock_irq(&epfile->ffs->eps_lock);
ddf8abd2 762
7fa68034
MN		 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 */
ddf8abd2
MN		 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 */
2e4c7553 775 struct usb_request *req;
ddf8abd2 776
c0d31b3c
DC		 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
2e4c7553
RB		 794 if (io_data->aio) {
795 req = usb_ep_alloc_request(ep->ep, GFP_KERNEL);
796 if (unlikely(!req))
48968f8d 797 goto error_lock;
ddf8abd2 798
2e4c7553 799 req->buf = data;
c0d31b3c 800 req->length = data_len;
ddf8abd2 801
2e4c7553
RB		 802 io_data->buf = data;
803 io_data->ep = ep->ep;
804 io_data->req = req;
5e33f6fd 805 io_data->ffs = epfile->ffs;
ddf8abd2 806
2e4c7553
RB		 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);
48968f8d 813 goto error_lock;
2e4c7553
RB		 814 }
815 ret = -EIOCBQUEUED;
816
817 spin_unlock_irq(&epfile->ffs->eps_lock);
ddf8abd2 818 } else {
2e4c7553
RB		 819 DECLARE_COMPLETION_ONSTACK(done);
820
821 req = ep->req;
822 req->buf = data;
c0d31b3c 823 req->length = data_len;
2e4c7553
RB		 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 {
cfe919b5
CL		 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) {
c993c39b
AV		 848 ret = copy_to_iter(data, ret, &io_data->data);
849 if (unlikely(iov_iter_count(&io_data->data)))
cfe919b5
CL		 850 ret = -EFAULT;
851 }
2e4c7553
RB		 852 }
853 kfree(data);
ddf8abd2
MN		 854 }
855 }
856
857 mutex_unlock(&epfile->mutex);
2e4c7553 858 return ret;
48968f8d
RB		 859
860error_lock:
861 spin_unlock_irq(&epfile->ffs->eps_lock);
862 mutex_unlock(&epfile->mutex);
ddf8abd2
MN		 863error:
864 kfree(data);
865 return ret;
866}
867
ddf8abd2
MN		 868static int
869ffs_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
2e4c7553
RB		 884static 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
70e60d91 904static ssize_t ffs_epfile_write_iter(struct kiocb *kiocb, struct iov_iter *from)
2e4c7553 905{
70e60d91 906 struct ffs_io_data io_data, *p = &io_data;
de2080d4 907 ssize_t res;
2e4c7553
RB		 908
909 ENTER();
910
70e60d91
AV		 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 }
2e4c7553 919
70e60d91
AV		 920 p->read = false;
921 p->kiocb = kiocb;
922 p->data = *from;
923 p->mm = current->mm;
2e4c7553 924
70e60d91 925 kiocb->private = p;
2e4c7553
RB		 926
927 kiocb_set_cancel_fn(kiocb, ffs_aio_cancel);
928
70e60d91
AV		 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;
de2080d4 936 return res;
2e4c7553
RB		 937}
938
70e60d91 939static ssize_t ffs_epfile_read_iter(struct kiocb *kiocb, struct iov_iter *to)
2e4c7553 940{
70e60d91 941 struct ffs_io_data io_data, *p = &io_data;
de2080d4 942 ssize_t res;
2e4c7553
RB		 943
944 ENTER();
945
70e60d91
AV		 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;
2e4c7553
RB		 953 }
954
70e60d91
AV		 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;
2e4c7553 968
70e60d91 969 kiocb->private = p;
2e4c7553
RB		 970
971 kiocb_set_cancel_fn(kiocb, ffs_aio_cancel);
972
70e60d91
AV		 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;
de2080d4
AV		 982 }
983 return res;
2e4c7553
RB		 984}
985
ddf8abd2
MN		 986static int
987ffs_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
ddf8abd2
MN		 998static 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;
c559a353
RB		 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 }
ddf8abd2
MN		 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
ddf8abd2 1059static const struct file_operations ffs_epfile_operations = {
ddf8abd2
MN		 1060 .llseek = no_llseek,
1061
1062 .open = ffs_epfile_open,
70e60d91
AV		 1063 .write = new_sync_write,
1064 .read = new_sync_read,
1065 .write_iter = ffs_epfile_write_iter,
1066 .read_iter = ffs_epfile_read_iter,
ddf8abd2
MN		 1067 .release = ffs_epfile_release,
1068 .unlocked_ioctl = ffs_epfile_ioctl,
1069};
1070
1071
ddf8abd2
MN		 1072/* File system and super block operations ***********************************/
1073
1074/*
5ab54cf7 1075 * Mounting the file system creates a controller file, used first for
ddf8abd2
MN		 1076 * function configuration then later for event monitoring.
1077 */
1078
ddf8abd2
MN		 1079static struct inode *__must_check
1080ffs_sb_make_inode(struct super_block *sb, void *data,
1081 const struct file_operations *fops,
1082 const struct inode_operations *iops,
1083 struct ffs_file_perms *perms)
1084{
1085 struct inode *inode;
1086
1087 ENTER();
1088
1089 inode = new_inode(sb);
1090
1091 if (likely(inode)) {
1092 struct timespec current_time = CURRENT_TIME;
1093
12ba8d1e 1094 inode->i_ino = get_next_ino();
ddf8abd2
MN		 1095 inode->i_mode = perms->mode;
1096 inode->i_uid = perms->uid;
1097 inode->i_gid = perms->gid;
1098 inode->i_atime = current_time;
1099 inode->i_mtime = current_time;
1100 inode->i_ctime = current_time;
1101 inode->i_private = data;
1102 if (fops)
1103 inode->i_fop = fops;
1104 if (iops)
1105 inode->i_op = iops;
1106 }
1107
1108 return inode;
1109}
1110
ddf8abd2 1111/* Create "regular" file */
1bb27cac 1112static struct dentry *ffs_sb_create_file(struct super_block *sb,
ddf8abd2 1113 const char *name, void *data,
1bb27cac 1114 const struct file_operations *fops)
ddf8abd2
MN		 1115{
1116 struct ffs_data *ffs = sb->s_fs_info;
1117 struct dentry *dentry;
1118 struct inode *inode;
1119
1120 ENTER();
1121
1122 dentry = d_alloc_name(sb->s_root, name);
1123 if (unlikely(!dentry))
1124 return NULL;
1125
1126 inode = ffs_sb_make_inode(sb, data, fops, NULL, &ffs->file_perms);
1127 if (unlikely(!inode)) {
1128 dput(dentry);
1129 return NULL;
1130 }
1131
1132 d_add(dentry, inode);
1bb27cac 1133 return dentry;
ddf8abd2
MN		 1134}
1135
ddf8abd2 1136/* Super block */
ddf8abd2
MN		 1137static const struct super_operations ffs_sb_operations = {
1138 .statfs = simple_statfs,
1139 .drop_inode = generic_delete_inode,
1140};
1141
1142struct ffs_sb_fill_data {
1143 struct ffs_file_perms perms;
1144 umode_t root_mode;
1145 const char *dev_name;
18d6b32f 1146 bool no_disconnect;
2606b28a 1147 struct ffs_data *ffs_data;
ddf8abd2
MN		 1148};
1149
1150static int ffs_sb_fill(struct super_block *sb, void *_data, int silent)
1151{
1152 struct ffs_sb_fill_data *data = _data;
1153 struct inode *inode;
2606b28a 1154 struct ffs_data *ffs = data->ffs_data;
ddf8abd2
MN		 1155
1156 ENTER();
1157
ddf8abd2 1158 ffs->sb = sb;
2606b28a 1159 data->ffs_data = NULL;
ddf8abd2
MN		 1160 sb->s_fs_info = ffs;
1161 sb->s_blocksize = PAGE_CACHE_SIZE;
1162 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
1163 sb->s_magic = FUNCTIONFS_MAGIC;
1164 sb->s_op = &ffs_sb_operations;
1165 sb->s_time_gran = 1;
1166
1167 /* Root inode */
1168 data->perms.mode = data->root_mode;
1169 inode = ffs_sb_make_inode(sb, NULL,
1170 &simple_dir_operations,
1171 &simple_dir_inode_operations,
1172 &data->perms);
48fde701
AV		 1173 sb->s_root = d_make_root(inode);
1174 if (unlikely(!sb->s_root))
2606b28a 1175 return -ENOMEM;
ddf8abd2
MN		 1176
1177 /* EP0 file */
1178 if (unlikely(!ffs_sb_create_file(sb, "ep0", ffs,
1bb27cac 1179 &ffs_ep0_operations)))
2606b28a 1180 return -ENOMEM;
ddf8abd2
MN		 1181
1182 return 0;
ddf8abd2
MN		 1183}
1184
ddf8abd2
MN		 1185static int ffs_fs_parse_opts(struct ffs_sb_fill_data *data, char *opts)
1186{
1187 ENTER();
1188
1189 if (!opts || !*opts)
1190 return 0;
1191
1192 for (;;) {
ddf8abd2 1193 unsigned long value;
afd2e186 1194 char *eq, *comma;
ddf8abd2
MN		 1195
1196 /* Option limit */
1197 comma = strchr(opts, ',');
1198 if (comma)
1199 *comma = 0;
1200
1201 /* Value limit */
1202 eq = strchr(opts, '=');
1203 if (unlikely(!eq)) {
aa02f172 1204 pr_err("'=' missing in %s\n", opts);
ddf8abd2
MN		 1205 return -EINVAL;
1206 }
1207 *eq = 0;
1208
1209 /* Parse value */
afd2e186 1210 if (kstrtoul(eq + 1, 0, &value)) {
aa02f172 1211 pr_err("%s: invalid value: %s\n", opts, eq + 1);
ddf8abd2
MN		 1212 return -EINVAL;
1213 }
1214
1215 /* Interpret option */
1216 switch (eq - opts) {
18d6b32f
RB		 1217 case 13:
1218 if (!memcmp(opts, "no_disconnect", 13))
1219 data->no_disconnect = !!value;
1220 else
1221 goto invalid;
1222 break;
ddf8abd2
MN		 1223 case 5:
1224 if (!memcmp(opts, "rmode", 5))
1225 data->root_mode = (value & 0555) | S_IFDIR;
1226 else if (!memcmp(opts, "fmode", 5))
1227 data->perms.mode = (value & 0666) | S_IFREG;
1228 else
1229 goto invalid;
1230 break;
1231
1232 case 4:
1233 if (!memcmp(opts, "mode", 4)) {
1234 data->root_mode = (value & 0555) | S_IFDIR;
1235 data->perms.mode = (value & 0666) | S_IFREG;
1236 } else {
1237 goto invalid;
1238 }
1239 break;
1240
1241 case 3:
b9b73f7c
EB		 1242 if (!memcmp(opts, "uid", 3)) {
1243 data->perms.uid = make_kuid(current_user_ns(), value);
1244 if (!uid_valid(data->perms.uid)) {
1245 pr_err("%s: unmapped value: %lu\n", opts, value);
1246 return -EINVAL;
1247 }
b8100750 1248 } else if (!memcmp(opts, "gid", 3)) {
b9b73f7c
EB		 1249 data->perms.gid = make_kgid(current_user_ns(), value);
1250 if (!gid_valid(data->perms.gid)) {
1251 pr_err("%s: unmapped value: %lu\n", opts, value);
1252 return -EINVAL;
1253 }
b8100750 1254 } else {
ddf8abd2 1255 goto invalid;
b8100750 1256 }
ddf8abd2
MN		 1257 break;
1258
1259 default:
1260invalid:
aa02f172 1261 pr_err("%s: invalid option\n", opts);
ddf8abd2
MN		 1262 return -EINVAL;
1263 }
1264
1265 /* Next iteration */
1266 if (!comma)
1267 break;
1268 opts = comma + 1;
1269 }
1270
1271 return 0;
1272}
1273
ddf8abd2
MN		 1274/* "mount -t functionfs dev_name /dev/function" ends up here */
1275
fc14f2fe
AV		 1276static struct dentry *
1277ffs_fs_mount(struct file_system_type *t, int flags,
1278 const char *dev_name, void *opts)
ddf8abd2
MN		 1279{
1280 struct ffs_sb_fill_data data = {
1281 .perms = {
1282 .mode = S_IFREG | 0600,
b9b73f7c
EB		 1283 .uid = GLOBAL_ROOT_UID,
1284 .gid = GLOBAL_ROOT_GID,
ddf8abd2
MN		 1285 },
1286 .root_mode = S_IFDIR | 0500,
18d6b32f 1287 .no_disconnect = false,
ddf8abd2 1288 };
581791f5 1289 struct dentry *rv;
ddf8abd2 1290 int ret;
581791f5 1291 void *ffs_dev;
2606b28a 1292 struct ffs_data *ffs;
ddf8abd2
MN		 1293
1294 ENTER();
1295
ddf8abd2
MN		 1296 ret = ffs_fs_parse_opts(&data, opts);
1297 if (unlikely(ret < 0))
fc14f2fe 1298 return ERR_PTR(ret);
ddf8abd2 1299
2606b28a
AV		 1300 ffs = ffs_data_new();
1301 if (unlikely(!ffs))
1302 return ERR_PTR(-ENOMEM);
1303 ffs->file_perms = data.perms;
18d6b32f 1304 ffs->no_disconnect = data.no_disconnect;
2606b28a
AV		 1305
1306 ffs->dev_name = kstrdup(dev_name, GFP_KERNEL);
1307 if (unlikely(!ffs->dev_name)) {
1308 ffs_data_put(ffs);
1309 return ERR_PTR(-ENOMEM);
1310 }
1311
4b187fce 1312 ffs_dev = ffs_acquire_dev(dev_name);
2606b28a
AV		 1313 if (IS_ERR(ffs_dev)) {
1314 ffs_data_put(ffs);
1315 return ERR_CAST(ffs_dev);
1316 }
1317 ffs->private_data = ffs_dev;
1318 data.ffs_data = ffs;
581791f5 1319
581791f5 1320 rv = mount_nodev(t, flags, &data, ffs_sb_fill);
2606b28a 1321 if (IS_ERR(rv) && data.ffs_data) {
4b187fce 1322 ffs_release_dev(data.ffs_data);
2606b28a
AV		 1323 ffs_data_put(data.ffs_data);
1324 }
581791f5 1325 return rv;
ddf8abd2
MN		 1326}
1327
1328static void
1329ffs_fs_kill_sb(struct super_block *sb)
1330{
ddf8abd2
MN		 1331 ENTER();
1332
1333 kill_litter_super(sb);
581791f5 1334 if (sb->s_fs_info) {
4b187fce 1335 ffs_release_dev(sb->s_fs_info);
18d6b32f 1336 ffs_data_closed(sb->s_fs_info);
5b5f9560 1337 ffs_data_put(sb->s_fs_info);
581791f5 1338 }
ddf8abd2
MN		 1339}
1340
1341static struct file_system_type ffs_fs_type = {
1342 .owner = THIS_MODULE,
1343 .name = "functionfs",
fc14f2fe 1344 .mount = ffs_fs_mount,
ddf8abd2
MN		 1345 .kill_sb = ffs_fs_kill_sb,
1346};
7f78e035 1347MODULE_ALIAS_FS("functionfs");
ddf8abd2
MN		 1348
1349
ddf8abd2
MN		 1350/* Driver's main init/cleanup functions *************************************/
1351
ddf8abd2
MN		 1352static int functionfs_init(void)
1353{
1354 int ret;
1355
1356 ENTER();
1357
1358 ret = register_filesystem(&ffs_fs_type);
1359 if (likely(!ret))
aa02f172 1360 pr_info("file system registered\n");
ddf8abd2 1361 else
aa02f172 1362 pr_err("failed registering file system (%d)\n", ret);
ddf8abd2
MN		 1363
1364 return ret;
1365}
1366
1367static void functionfs_cleanup(void)
1368{
1369 ENTER();
1370
aa02f172 1371 pr_info("unloading\n");
ddf8abd2
MN		 1372 unregister_filesystem(&ffs_fs_type);
1373}
1374
1375
ddf8abd2
MN		 1376/* ffs_data and ffs_function construction and destruction code **************/
1377
1378static void ffs_data_clear(struct ffs_data *ffs);
1379static void ffs_data_reset(struct ffs_data *ffs);
1380
ddf8abd2
MN		 1381static void ffs_data_get(struct ffs_data *ffs)
1382{
1383 ENTER();
1384
1385 atomic_inc(&ffs->ref);
1386}
1387
1388static void ffs_data_opened(struct ffs_data *ffs)
1389{
1390 ENTER();
1391
1392 atomic_inc(&ffs->ref);
18d6b32f
RB		 1393 if (atomic_add_return(1, &ffs->opened) == 1 &&
1394 ffs->state == FFS_DEACTIVATED) {
1395 ffs->state = FFS_CLOSING;
1396 ffs_data_reset(ffs);
1397 }
ddf8abd2
MN		 1398}
1399
1400static void ffs_data_put(struct ffs_data *ffs)
1401{
1402 ENTER();
1403
1404 if (unlikely(atomic_dec_and_test(&ffs->ref))) {
aa02f172 1405 pr_info("%s(): freeing\n", __func__);
ddf8abd2 1406 ffs_data_clear(ffs);
647d5580 1407 BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
ddf8abd2 1408 waitqueue_active(&ffs->ep0req_completion.wait));
581791f5 1409 kfree(ffs->dev_name);
ddf8abd2
MN		 1410 kfree(ffs);
1411 }
1412}
1413
ddf8abd2
MN		 1414static void ffs_data_closed(struct ffs_data *ffs)
1415{
1416 ENTER();
1417
1418 if (atomic_dec_and_test(&ffs->opened)) {
18d6b32f
RB		 1419 if (ffs->no_disconnect) {
1420 ffs->state = FFS_DEACTIVATED;
1421 if (ffs->epfiles) {
1422 ffs_epfiles_destroy(ffs->epfiles,
1423 ffs->eps_count);
1424 ffs->epfiles = NULL;
1425 }
1426 if (ffs->setup_state == FFS_SETUP_PENDING)
1427 __ffs_ep0_stall(ffs);
1428 } else {
1429 ffs->state = FFS_CLOSING;
1430 ffs_data_reset(ffs);
1431 }
1432 }
1433 if (atomic_read(&ffs->opened) < 0) {
ddf8abd2
MN		 1434 ffs->state = FFS_CLOSING;
1435 ffs_data_reset(ffs);
1436 }
1437
1438 ffs_data_put(ffs);
1439}
1440
ddf8abd2
MN		 1441static struct ffs_data *ffs_data_new(void)
1442{
1443 struct ffs_data *ffs = kzalloc(sizeof *ffs, GFP_KERNEL);
1444 if (unlikely(!ffs))
f8800d47 1445 return NULL;
ddf8abd2
MN		 1446
1447 ENTER();
1448
1449 atomic_set(&ffs->ref, 1);
1450 atomic_set(&ffs->opened, 0);
1451 ffs->state = FFS_READ_DESCRIPTORS;
1452 mutex_init(&ffs->mutex);
1453 spin_lock_init(&ffs->eps_lock);
1454 init_waitqueue_head(&ffs->ev.waitq);
1455 init_completion(&ffs->ep0req_completion);
1456
1457 /* XXX REVISIT need to update it in some places, or do we? */
1458 ffs->ev.can_stall = 1;
1459
1460 return ffs;
1461}
1462
ddf8abd2
MN		 1463static void ffs_data_clear(struct ffs_data *ffs)
1464{
1465 ENTER();
1466
1467 if (test_and_clear_bit(FFS_FL_CALL_CLOSED_CALLBACK, &ffs->flags))
4b187fce 1468 ffs_closed(ffs);
ddf8abd2
MN		 1469
1470 BUG_ON(ffs->gadget);
1471
1472 if (ffs->epfiles)
1473 ffs_epfiles_destroy(ffs->epfiles, ffs->eps_count);
1474
5e33f6fd
RB		 1475 if (ffs->ffs_eventfd)
1476 eventfd_ctx_put(ffs->ffs_eventfd);
1477
ac8dde11 1478 kfree(ffs->raw_descs_data);
ddf8abd2
MN		 1479 kfree(ffs->raw_strings);
1480 kfree(ffs->stringtabs);
1481}
1482
ddf8abd2
MN		 1483static void ffs_data_reset(struct ffs_data *ffs)
1484{
1485 ENTER();
1486
1487 ffs_data_clear(ffs);
1488
1489 ffs->epfiles = NULL;
ac8dde11 1490 ffs->raw_descs_data = NULL;
ddf8abd2
MN		 1491 ffs->raw_descs = NULL;
1492 ffs->raw_strings = NULL;
1493 ffs->stringtabs = NULL;
1494
1495 ffs->raw_descs_length = 0;
ddf8abd2
MN		 1496 ffs->fs_descs_count = 0;
1497 ffs->hs_descs_count = 0;
8d4e897b 1498 ffs->ss_descs_count = 0;
ddf8abd2
MN		 1499
1500 ffs->strings_count = 0;
1501 ffs->interfaces_count = 0;
1502 ffs->eps_count = 0;
1503
1504 ffs->ev.count = 0;
1505
1506 ffs->state = FFS_READ_DESCRIPTORS;
1507 ffs->setup_state = FFS_NO_SETUP;
1508 ffs->flags = 0;
1509}
1510
1511
1512static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
1513{
fd7c9a00
MN		 1514 struct usb_gadget_strings **lang;
1515 int first_id;
ddf8abd2
MN		 1516
1517 ENTER();
1518
1519 if (WARN_ON(ffs->state != FFS_ACTIVE
1520 || test_and_set_bit(FFS_FL_BOUND, &ffs->flags)))
1521 return -EBADFD;
1522
fd7c9a00
MN		 1523 first_id = usb_string_ids_n(cdev, ffs->strings_count);
1524 if (unlikely(first_id < 0))
1525 return first_id;
ddf8abd2
MN		 1526
1527 ffs->ep0req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
1528 if (unlikely(!ffs->ep0req))
1529 return -ENOMEM;
1530 ffs->ep0req->complete = ffs_ep0_complete;
1531 ffs->ep0req->context = ffs;
1532
fd7c9a00 1533 lang = ffs->stringtabs;
f0688c8b
MN		 1534 if (lang) {
1535 for (; *lang; ++lang) {
1536 struct usb_string *str = (*lang)->strings;
1537 int id = first_id;
1538 for (; str->s; ++id, ++str)
1539 str->id = id;
1540 }
ddf8abd2
MN		 1541 }
1542
1543 ffs->gadget = cdev->gadget;
fd7c9a00 1544 ffs_data_get(ffs);
ddf8abd2
MN		 1545 return 0;
1546}
1547
ddf8abd2
MN		 1548static void functionfs_unbind(struct ffs_data *ffs)
1549{
1550 ENTER();
1551
1552 if (!WARN_ON(!ffs->gadget)) {
1553 usb_ep_free_request(ffs->gadget->ep0, ffs->ep0req);
1554 ffs->ep0req = NULL;
1555 ffs->gadget = NULL;
e2190a97 1556 clear_bit(FFS_FL_BOUND, &ffs->flags);
df498995 1557 ffs_data_put(ffs);
ddf8abd2
MN		 1558 }
1559}
1560
ddf8abd2
MN		 1561static int ffs_epfiles_create(struct ffs_data *ffs)
1562{
1563 struct ffs_epfile *epfile, *epfiles;
1564 unsigned i, count;
1565
1566 ENTER();
1567
1568 count = ffs->eps_count;
9823a525 1569 epfiles = kcalloc(count, sizeof(*epfiles), GFP_KERNEL);
ddf8abd2
MN		 1570 if (!epfiles)
1571 return -ENOMEM;
1572
1573 epfile = epfiles;
1574 for (i = 1; i <= count; ++i, ++epfile) {
1575 epfile->ffs = ffs;
1576 mutex_init(&epfile->mutex);
1577 init_waitqueue_head(&epfile->wait);
1b0bf88f 1578 if (ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
acba23fe 1579 sprintf(epfile->name, "ep%02x", ffs->eps_addrmap[i]);
1b0bf88f 1580 else
acba23fe
MS		 1581 sprintf(epfile->name, "ep%u", i);
1582 epfile->dentry = ffs_sb_create_file(ffs->sb, epfile->name,
1bb27cac
AV		 1583 epfile,
1584 &ffs_epfile_operations);
1585 if (unlikely(!epfile->dentry)) {
ddf8abd2
MN		 1586 ffs_epfiles_destroy(epfiles, i - 1);
1587 return -ENOMEM;
1588 }
1589 }
1590
1591 ffs->epfiles = epfiles;
1592 return 0;
1593}
1594
ddf8abd2
MN		 1595static void ffs_epfiles_destroy(struct ffs_epfile *epfiles, unsigned count)
1596{
1597 struct ffs_epfile *epfile = epfiles;
1598
1599 ENTER();
1600
1601 for (; count; --count, ++epfile) {
1602 BUG_ON(mutex_is_locked(&epfile->mutex) ||
1603 waitqueue_active(&epfile->wait));
1604 if (epfile->dentry) {
1605 d_delete(epfile->dentry);
1606 dput(epfile->dentry);
1607 epfile->dentry = NULL;
1608 }
1609 }
1610
1611 kfree(epfiles);
1612}
1613
ddf8abd2
MN		 1614static void ffs_func_eps_disable(struct ffs_function *func)
1615{
1616 struct ffs_ep *ep = func->eps;
1617 struct ffs_epfile *epfile = func->ffs->epfiles;
1618 unsigned count = func->ffs->eps_count;
1619 unsigned long flags;
1620
1621 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1622 do {
1623 /* pending requests get nuked */
1624 if (likely(ep->ep))
1625 usb_ep_disable(ep->ep);
ddf8abd2 1626 ++ep;
18d6b32f
RB		 1627
1628 if (epfile) {
1629 epfile->ep = NULL;
1630 ++epfile;
1631 }
ddf8abd2
MN		 1632 } while (--count);
1633 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1634}
1635
1636static int ffs_func_eps_enable(struct ffs_function *func)
1637{
1638 struct ffs_data *ffs = func->ffs;
1639 struct ffs_ep *ep = func->eps;
1640 struct ffs_epfile *epfile = ffs->epfiles;
1641 unsigned count = ffs->eps_count;
1642 unsigned long flags;
1643 int ret = 0;
1644
1645 spin_lock_irqsave(&func->ffs->eps_lock, flags);
1646 do {
1647 struct usb_endpoint_descriptor *ds;
8d4e897b
MG		 1648 int desc_idx;
1649
1650 if (ffs->gadget->speed == USB_SPEED_SUPER)
1651 desc_idx = 2;
1652 else if (ffs->gadget->speed == USB_SPEED_HIGH)
1653 desc_idx = 1;
1654 else
1655 desc_idx = 0;
1656
1657 /* fall-back to lower speed if desc missing for current speed */
1658 do {
1659 ds = ep->descs[desc_idx];
1660 } while (!ds && --desc_idx >= 0);
1661
1662 if (!ds) {
1663 ret = -EINVAL;
1664 break;
1665 }
ddf8abd2
MN		 1666
1667 ep->ep->driver_data = ep;
72c973dd
TB		 1668 ep->ep->desc = ds;
1669 ret = usb_ep_enable(ep->ep);
ddf8abd2
MN		 1670 if (likely(!ret)) {
1671 epfile->ep = ep;
1672 epfile->in = usb_endpoint_dir_in(ds);
1673 epfile->isoc = usb_endpoint_xfer_isoc(ds);
1674 } else {
1675 break;
1676 }
1677
1678 wake_up(&epfile->wait);
1679
1680 ++ep;
1681 ++epfile;
1682 } while (--count);
1683 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
1684
1685 return ret;
1686}
1687
1688
1689/* Parsing and building descriptors and strings *****************************/
1690
5ab54cf7
MN		 1691/*
1692 * This validates if data pointed by data is a valid USB descriptor as
ddf8abd2 1693 * well as record how many interfaces, endpoints and strings are
5ab54cf7
MN		 1694 * required by given configuration. Returns address after the
1695 * descriptor or NULL if data is invalid.
1696 */
ddf8abd2
MN		 1697
1698enum ffs_entity_type {
1699 FFS_DESCRIPTOR, FFS_INTERFACE, FFS_STRING, FFS_ENDPOINT
1700};
1701
f0175ab5
AP		 1702enum ffs_os_desc_type {
1703 FFS_OS_DESC, FFS_OS_DESC_EXT_COMPAT, FFS_OS_DESC_EXT_PROP
1704};
1705
ddf8abd2
MN		 1706typedef int (*ffs_entity_callback)(enum ffs_entity_type entity,
1707 u8 *valuep,
1708 struct usb_descriptor_header *desc,
1709 void *priv);
1710
f0175ab5
AP		 1711typedef int (*ffs_os_desc_callback)(enum ffs_os_desc_type entity,
1712 struct usb_os_desc_header *h, void *data,
1713 unsigned len, void *priv);
1714
f96cbd14
AP		 1715static int __must_check ffs_do_single_desc(char *data, unsigned len,
1716 ffs_entity_callback entity,
1717 void *priv)
ddf8abd2
MN		 1718{
1719 struct usb_descriptor_header *_ds = (void *)data;
1720 u8 length;
1721 int ret;
1722
1723 ENTER();
1724
1725 /* At least two bytes are required: length and type */
1726 if (len < 2) {
aa02f172 1727 pr_vdebug("descriptor too short\n");
ddf8abd2
MN		 1728 return -EINVAL;
1729 }
1730
1731 /* If we have at least as many bytes as the descriptor takes? */
1732 length = _ds->bLength;
1733 if (len < length) {
aa02f172 1734 pr_vdebug("descriptor longer then available data\n");
ddf8abd2
MN		 1735 return -EINVAL;
1736 }
1737
1738#define __entity_check_INTERFACE(val) 1
1739#define __entity_check_STRING(val) (val)
1740#define __entity_check_ENDPOINT(val) ((val) & USB_ENDPOINT_NUMBER_MASK)
1741#define __entity(type, val) do { \
aa02f172 1742 pr_vdebug("entity " #type "(%02x)\n", (val)); \
ddf8abd2 1743 if (unlikely(!__entity_check_ ##type(val))) { \
aa02f172 1744 pr_vdebug("invalid entity's value\n"); \
ddf8abd2
MN		 1745 return -EINVAL; \
1746 } \
1747 ret = entity(FFS_ ##type, &val, _ds, priv); \
1748 if (unlikely(ret < 0)) { \
aa02f172 1749 pr_debug("entity " #type "(%02x); ret = %d\n", \
d8df0b61 1750 (val), ret); \
ddf8abd2
MN		 1751 return ret; \
1752 } \
1753 } while (0)
1754
1755 /* Parse descriptor depending on type. */
1756 switch (_ds->bDescriptorType) {
1757 case USB_DT_DEVICE:
1758 case USB_DT_CONFIG:
1759 case USB_DT_STRING:
1760 case USB_DT_DEVICE_QUALIFIER:
1761 /* function can't have any of those */
aa02f172 1762 pr_vdebug("descriptor reserved for gadget: %d\n",
5ab54cf7 1763 _ds->bDescriptorType);
ddf8abd2
MN		 1764 return -EINVAL;
1765
1766 case USB_DT_INTERFACE: {
1767 struct usb_interface_descriptor *ds = (void *)_ds;
aa02f172 1768 pr_vdebug("interface descriptor\n");
ddf8abd2
MN		 1769 if (length != sizeof *ds)
1770 goto inv_length;
1771
1772 __entity(INTERFACE, ds->bInterfaceNumber);
1773 if (ds->iInterface)
1774 __entity(STRING, ds->iInterface);
1775 }
1776 break;
1777
1778 case USB_DT_ENDPOINT: {
1779 struct usb_endpoint_descriptor *ds = (void *)_ds;
aa02f172 1780 pr_vdebug("endpoint descriptor\n");
ddf8abd2
MN		 1781 if (length != USB_DT_ENDPOINT_SIZE &&
1782 length != USB_DT_ENDPOINT_AUDIO_SIZE)
1783 goto inv_length;
1784 __entity(ENDPOINT, ds->bEndpointAddress);
1785 }
1786 break;
1787
560f1187
KB		 1788 case HID_DT_HID:
1789 pr_vdebug("hid descriptor\n");
1790 if (length != sizeof(struct hid_descriptor))
1791 goto inv_length;
1792 break;
1793
ddf8abd2
MN		 1794 case USB_DT_OTG:
1795 if (length != sizeof(struct usb_otg_descriptor))
1796 goto inv_length;
1797 break;
1798
1799 case USB_DT_INTERFACE_ASSOCIATION: {
1800 struct usb_interface_assoc_descriptor *ds = (void *)_ds;
aa02f172 1801 pr_vdebug("interface association descriptor\n");
ddf8abd2
MN		 1802 if (length != sizeof *ds)
1803 goto inv_length;
1804 if (ds->iFunction)
1805 __entity(STRING, ds->iFunction);
1806 }
1807 break;
1808
8d4e897b
MG		 1809 case USB_DT_SS_ENDPOINT_COMP:
1810 pr_vdebug("EP SS companion descriptor\n");
1811 if (length != sizeof(struct usb_ss_ep_comp_descriptor))
1812 goto inv_length;
1813 break;
1814
ddf8abd2
MN		 1815 case USB_DT_OTHER_SPEED_CONFIG:
1816 case USB_DT_INTERFACE_POWER:
1817 case USB_DT_DEBUG:
1818 case USB_DT_SECURITY:
1819 case USB_DT_CS_RADIO_CONTROL:
1820 /* TODO */
aa02f172 1821 pr_vdebug("unimplemented descriptor: %d\n", _ds->bDescriptorType);
ddf8abd2
MN		 1822 return -EINVAL;
1823
1824 default:
1825 /* We should never be here */
aa02f172 1826 pr_vdebug("unknown descriptor: %d\n", _ds->bDescriptorType);
ddf8abd2
MN		 1827 return -EINVAL;
1828
5ab54cf7 1829inv_length:
aa02f172 1830 pr_vdebug("invalid length: %d (descriptor %d)\n",
d8df0b61 1831 _ds->bLength, _ds->bDescriptorType);
ddf8abd2
MN		 1832 return -EINVAL;
1833 }
1834
1835#undef __entity
1836#undef __entity_check_DESCRIPTOR
1837#undef __entity_check_INTERFACE
1838#undef __entity_check_STRING
1839#undef __entity_check_ENDPOINT
1840
1841 return length;
1842}
1843
ddf8abd2
MN		 1844static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
1845 ffs_entity_callback entity, void *priv)
1846{
1847 const unsigned _len = len;
1848 unsigned long num = 0;
1849
1850 ENTER();
1851
1852 for (;;) {
1853 int ret;
1854
1855 if (num == count)
1856 data = NULL;
1857
5ab54cf7 1858 /* Record "descriptor" entity */
ddf8abd2
MN		 1859 ret = entity(FFS_DESCRIPTOR, (u8 *)num, (void *)data, priv);
1860 if (unlikely(ret < 0)) {
aa02f172 1861 pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
d8df0b61 1862 num, ret);
ddf8abd2
MN		 1863 return ret;
1864 }
1865
1866 if (!data)
1867 return _len - len;
1868
f96cbd14 1869 ret = ffs_do_single_desc(data, len, entity, priv);
ddf8abd2 1870 if (unlikely(ret < 0)) {
aa02f172 1871 pr_debug("%s returns %d\n", __func__, ret);
ddf8abd2
MN		 1872 return ret;
1873 }
1874
1875 len -= ret;
1876 data += ret;
1877 ++num;
1878 }
1879}
1880
ddf8abd2
MN		 1881static int __ffs_data_do_entity(enum ffs_entity_type type,
1882 u8 *valuep, struct usb_descriptor_header *desc,
1883 void *priv)
1884{
6d5c1c77
RB		 1885 struct ffs_desc_helper *helper = priv;
1886 struct usb_endpoint_descriptor *d;
ddf8abd2
MN		 1887
1888 ENTER();
1889
1890 switch (type) {
1891 case FFS_DESCRIPTOR:
1892 break;
1893
1894 case FFS_INTERFACE:
5ab54cf7
MN		 1895 /*
1896 * Interfaces are indexed from zero so if we
ddf8abd2 1897 * encountered interface "n" then there are at least
5ab54cf7
MN		 1898 * "n+1" interfaces.
1899 */
6d5c1c77
RB		 1900 if (*valuep >= helper->interfaces_count)
1901 helper->interfaces_count = *valuep + 1;
ddf8abd2
MN		 1902 break;
1903
1904 case FFS_STRING:
5ab54cf7
MN		 1905 /*
1906 * Strings are indexed from 1 (0 is magic ;) reserved
1907 * for languages list or some such)
1908 */
6d5c1c77
RB		 1909 if (*valuep > helper->ffs->strings_count)
1910 helper->ffs->strings_count = *valuep;
ddf8abd2
MN		 1911 break;
1912
1913 case FFS_ENDPOINT:
6d5c1c77
RB		 1914 d = (void *)desc;
1915 helper->eps_count++;
1916 if (helper->eps_count >= 15)
1917 return -EINVAL;
1918 /* Check if descriptors for any speed were already parsed */
1919 if (!helper->ffs->eps_count && !helper->ffs->interfaces_count)
1920 helper->ffs->eps_addrmap[helper->eps_count] =
1921 d->bEndpointAddress;
1922 else if (helper->ffs->eps_addrmap[helper->eps_count] !=
1923 d->bEndpointAddress)
1924 return -EINVAL;
ddf8abd2
MN		 1925 break;
1926 }
1927
1928 return 0;
1929}
1930
f0175ab5
AP		 1931static int __ffs_do_os_desc_header(enum ffs_os_desc_type *next_type,
1932 struct usb_os_desc_header *desc)
1933{
1934 u16 bcd_version = le16_to_cpu(desc->bcdVersion);
1935 u16 w_index = le16_to_cpu(desc->wIndex);
1936
1937 if (bcd_version != 1) {
1938 pr_vdebug("unsupported os descriptors version: %d",
1939 bcd_version);
1940 return -EINVAL;
1941 }
1942 switch (w_index) {
1943 case 0x4:
1944 *next_type = FFS_OS_DESC_EXT_COMPAT;
1945 break;
1946 case 0x5:
1947 *next_type = FFS_OS_DESC_EXT_PROP;
1948 break;
1949 default:
1950 pr_vdebug("unsupported os descriptor type: %d", w_index);
1951 return -EINVAL;
1952 }
1953
1954 return sizeof(*desc);
1955}
1956
1957/*
1958 * Process all extended compatibility/extended property descriptors
1959 * of a feature descriptor
1960 */
1961static int __must_check ffs_do_single_os_desc(char *data, unsigned len,
1962 enum ffs_os_desc_type type,
1963 u16 feature_count,
1964 ffs_os_desc_callback entity,
1965 void *priv,
1966 struct usb_os_desc_header *h)
1967{
1968 int ret;
1969 const unsigned _len = len;
1970
1971 ENTER();
1972
1973 /* loop over all ext compat/ext prop descriptors */
1974 while (feature_count--) {
1975 ret = entity(type, h, data, len, priv);
1976 if (unlikely(ret < 0)) {
1977 pr_debug("bad OS descriptor, type: %d\n", type);
1978 return ret;
1979 }
1980 data += ret;
1981 len -= ret;
1982 }
1983 return _len - len;
1984}
1985
1986/* Process a number of complete Feature Descriptors (Ext Compat or Ext Prop) */
1987static int __must_check ffs_do_os_descs(unsigned count,
1988 char *data, unsigned len,
1989 ffs_os_desc_callback entity, void *priv)
1990{
1991 const unsigned _len = len;
1992 unsigned long num = 0;
1993
1994 ENTER();
1995
1996 for (num = 0; num < count; ++num) {
1997 int ret;
1998 enum ffs_os_desc_type type;
1999 u16 feature_count;
2000 struct usb_os_desc_header *desc = (void *)data;
2001
2002 if (len < sizeof(*desc))
2003 return -EINVAL;
2004
2005 /*
2006 * Record "descriptor" entity.
2007 * Process dwLength, bcdVersion, wIndex, get b/wCount.
2008 * Move the data pointer to the beginning of extended
2009 * compatibilities proper or extended properties proper
2010 * portions of the data
2011 */
2012 if (le32_to_cpu(desc->dwLength) > len)
2013 return -EINVAL;
2014
2015 ret = __ffs_do_os_desc_header(&type, desc);
2016 if (unlikely(ret < 0)) {
2017 pr_debug("entity OS_DESCRIPTOR(%02lx); ret = %d\n",
2018 num, ret);
2019 return ret;
2020 }
2021 /*
2022 * 16-bit hex "?? 00" Little Endian looks like 8-bit hex "??"
2023 */
2024 feature_count = le16_to_cpu(desc->wCount);
2025 if (type == FFS_OS_DESC_EXT_COMPAT &&
2026 (feature_count > 255 || desc->Reserved))
2027 return -EINVAL;
2028 len -= ret;
2029 data += ret;
2030
2031 /*
2032 * Process all function/property descriptors
2033 * of this Feature Descriptor
2034 */
2035 ret = ffs_do_single_os_desc(data, len, type,
2036 feature_count, entity, priv, desc);
2037 if (unlikely(ret < 0)) {
2038 pr_debug("%s returns %d\n", __func__, ret);
2039 return ret;
2040 }
2041
2042 len -= ret;
2043 data += ret;
2044 }
2045 return _len - len;
2046}
2047
2048/**
2049 * Validate contents of the buffer from userspace related to OS descriptors.
2050 */
2051static int __ffs_data_do_os_desc(enum ffs_os_desc_type type,
2052 struct usb_os_desc_header *h, void *data,
2053 unsigned len, void *priv)
2054{
2055 struct ffs_data *ffs = priv;
2056 u8 length;
2057
2058 ENTER();
2059
2060 switch (type) {
2061 case FFS_OS_DESC_EXT_COMPAT: {
2062 struct usb_ext_compat_desc *d = data;
2063 int i;
2064
2065 if (len < sizeof(*d) ||
2066 d->bFirstInterfaceNumber >= ffs->interfaces_count ||
2067 d->Reserved1)
2068 return -EINVAL;
2069 for (i = 0; i < ARRAY_SIZE(d->Reserved2); ++i)
2070 if (d->Reserved2[i])
2071 return -EINVAL;
2072
2073 length = sizeof(struct usb_ext_compat_desc);
2074 }
2075 break;
2076 case FFS_OS_DESC_EXT_PROP: {
2077 struct usb_ext_prop_desc *d = data;
2078 u32 type, pdl;
2079 u16 pnl;
2080
2081 if (len < sizeof(*d) || h->interface >= ffs->interfaces_count)
2082 return -EINVAL;
2083 length = le32_to_cpu(d->dwSize);
2084 type = le32_to_cpu(d->dwPropertyDataType);
2085 if (type < USB_EXT_PROP_UNICODE ||
2086 type > USB_EXT_PROP_UNICODE_MULTI) {
2087 pr_vdebug("unsupported os descriptor property type: %d",
2088 type);
2089 return -EINVAL;
2090 }
2091 pnl = le16_to_cpu(d->wPropertyNameLength);
2092 pdl = le32_to_cpu(*(u32 *)((u8 *)data + 10 + pnl));
2093 if (length != 14 + pnl + pdl) {
2094 pr_vdebug("invalid os descriptor length: %d pnl:%d pdl:%d (descriptor %d)\n",
2095 length, pnl, pdl, type);
2096 return -EINVAL;
2097 }
2098 ++ffs->ms_os_descs_ext_prop_count;
2099 /* property name reported to the host as "WCHAR"s */
2100 ffs->ms_os_descs_ext_prop_name_len += pnl * 2;
2101 ffs->ms_os_descs_ext_prop_data_len += pdl;
2102 }
2103 break;
2104 default:
2105 pr_vdebug("unknown descriptor: %d\n", type);
2106 return -EINVAL;
2107 }
2108 return length;
2109}
2110
ddf8abd2
MN		 2111static int __ffs_data_got_descs(struct ffs_data *ffs,
2112 char *const _data, size_t len)
2113{
ac8dde11 2114 char *data = _data, *raw_descs;
f0175ab5 2115 unsigned os_descs_count = 0, counts[3], flags;
ac8dde11 2116 int ret = -EINVAL, i;
6d5c1c77 2117 struct ffs_desc_helper helper;
ddf8abd2
MN		 2118
2119 ENTER();
2120
ac8dde11 2121 if (get_unaligned_le32(data + 4) != len)
ddf8abd2 2122 goto error;
ddf8abd2 2123
ac8dde11
MN		 2124 switch (get_unaligned_le32(data)) {
2125 case FUNCTIONFS_DESCRIPTORS_MAGIC:
2126 flags = FUNCTIONFS_HAS_FS_DESC | FUNCTIONFS_HAS_HS_DESC;
2127 data += 8;
2128 len -= 8;
2129 break;
2130 case FUNCTIONFS_DESCRIPTORS_MAGIC_V2:
2131 flags = get_unaligned_le32(data + 8);
1b0bf88f 2132 ffs->user_flags = flags;
ac8dde11
MN		 2133 if (flags & ~(FUNCTIONFS_HAS_FS_DESC |
2134 FUNCTIONFS_HAS_HS_DESC |
f0175ab5 2135 FUNCTIONFS_HAS_SS_DESC |
1b0bf88f 2136 FUNCTIONFS_HAS_MS_OS_DESC |
5e33f6fd
RB		 2137 FUNCTIONFS_VIRTUAL_ADDR |
2138 FUNCTIONFS_EVENTFD)) {
ac8dde11 2139 ret = -ENOSYS;
ddf8abd2
MN		 2140 goto error;
2141 }
ac8dde11
MN		 2142 data += 12;
2143 len -= 12;
2144 break;
2145 default:
2146 goto error;
ddf8abd2 2147 }
ddf8abd2 2148
5e33f6fd
RB		 2149 if (flags & FUNCTIONFS_EVENTFD) {
2150 if (len < 4)
2151 goto error;
2152 ffs->ffs_eventfd =
2153 eventfd_ctx_fdget((int)get_unaligned_le32(data));
2154 if (IS_ERR(ffs->ffs_eventfd)) {
2155 ret = PTR_ERR(ffs->ffs_eventfd);
2156 ffs->ffs_eventfd = NULL;
2157 goto error;
2158 }
2159 data += 4;
2160 len -= 4;
2161 }
2162
ac8dde11
MN		 2163 /* Read fs_count, hs_count and ss_count (if present) */
2164 for (i = 0; i < 3; ++i) {
2165 if (!(flags & (1 << i))) {
2166 counts[i] = 0;
2167 } else if (len < 4) {
8d4e897b 2168 goto error;
ac8dde11
MN		 2169 } else {
2170 counts[i] = get_unaligned_le32(data);
2171 data += 4;
2172 len -= 4;
8d4e897b 2173 }
ddf8abd2 2174 }
f0175ab5
AP		 2175 if (flags & (1 << i)) {
2176 os_descs_count = get_unaligned_le32(data);
2177 data += 4;
2178 len -= 4;
2179 };
ddf8abd2 2180
ac8dde11
MN		 2181 /* Read descriptors */
2182 raw_descs = data;
6d5c1c77 2183 helper.ffs = ffs;
ac8dde11
MN		 2184 for (i = 0; i < 3; ++i) {
2185 if (!counts[i])
2186 continue;
6d5c1c77
RB		 2187 helper.interfaces_count = 0;
2188 helper.eps_count = 0;
ac8dde11 2189 ret = ffs_do_descs(counts[i], data, len,
6d5c1c77 2190 __ffs_data_do_entity, &helper);
ac8dde11 2191 if (ret < 0)
ddf8abd2 2192 goto error;
6d5c1c77
RB		 2193 if (!ffs->eps_count && !ffs->interfaces_count) {
2194 ffs->eps_count = helper.eps_count;
2195 ffs->interfaces_count = helper.interfaces_count;
2196 } else {
2197 if (ffs->eps_count != helper.eps_count) {
2198 ret = -EINVAL;
2199 goto error;
2200 }
2201 if (ffs->interfaces_count != helper.interfaces_count) {
2202 ret = -EINVAL;
2203 goto error;
2204 }
2205 }
ac8dde11
MN		 2206 data += ret;
2207 len -= ret;
ddf8abd2 2208 }
f0175ab5
AP		 2209 if (os_descs_count) {
2210 ret = ffs_do_os_descs(os_descs_count, data, len,
2211 __ffs_data_do_os_desc, ffs);
2212 if (ret < 0)
2213 goto error;
2214 data += ret;
2215 len -= ret;
2216 }
ddf8abd2 2217
ac8dde11
MN		 2218 if (raw_descs == data || len) {
2219 ret = -EINVAL;
2220 goto error;
2221 }
ddf8abd2 2222
ac8dde11
MN		 2223 ffs->raw_descs_data = _data;
2224 ffs->raw_descs = raw_descs;
2225 ffs->raw_descs_length = data - raw_descs;
2226 ffs->fs_descs_count = counts[0];
2227 ffs->hs_descs_count = counts[1];
2228 ffs->ss_descs_count = counts[2];
f0175ab5 2229 ffs->ms_os_descs_count = os_descs_count;
ddf8abd2
MN		 2230
2231 return 0;
2232
ddf8abd2
MN		 2233error:
2234 kfree(_data);
2235 return ret;
2236}
2237
ddf8abd2
MN		 2238static int __ffs_data_got_strings(struct ffs_data *ffs,
2239 char *const _data, size_t len)
2240{
2241 u32 str_count, needed_count, lang_count;
2242 struct usb_gadget_strings **stringtabs, *t;
2243 struct usb_string *strings, *s;
2244 const char *data = _data;
2245
2246 ENTER();
2247
2248 if (unlikely(get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
2249 get_unaligned_le32(data + 4) != len))
2250 goto error;
2251 str_count = get_unaligned_le32(data + 8);
2252 lang_count = get_unaligned_le32(data + 12);
2253
2254 /* if one is zero the other must be zero */
2255 if (unlikely(!str_count != !lang_count))
2256 goto error;
2257
2258 /* Do we have at least as many strings as descriptors need? */
2259 needed_count = ffs->strings_count;
2260 if (unlikely(str_count < needed_count))
2261 goto error;
2262
5ab54cf7
MN		 2263 /*
2264 * If we don't need any strings just return and free all
2265 * memory.
2266 */
ddf8abd2
MN		 2267 if (!needed_count) {
2268 kfree(_data);
2269 return 0;
2270 }
2271
5ab54cf7 2272 /* Allocate everything in one chunk so there's less maintenance. */
ddf8abd2 2273 {
ddf8abd2 2274 unsigned i = 0;
e6f3862f
AP		 2275 vla_group(d);
2276 vla_item(d, struct usb_gadget_strings *, stringtabs,
2277 lang_count + 1);
2278 vla_item(d, struct usb_gadget_strings, stringtab, lang_count);
2279 vla_item(d, struct usb_string, strings,
2280 lang_count*(needed_count+1));
ddf8abd2 2281
e6f3862f
AP		 2282 char *vlabuf = kmalloc(vla_group_size(d), GFP_KERNEL);
2283
2284 if (unlikely(!vlabuf)) {
ddf8abd2
MN		 2285 kfree(_data);
2286 return -ENOMEM;
2287 }
2288
e6f3862f
AP		 2289 /* Initialize the VLA pointers */
2290 stringtabs = vla_ptr(vlabuf, d, stringtabs);
2291 t = vla_ptr(vlabuf, d, stringtab);
ddf8abd2
MN		 2292 i = lang_count;
2293 do {
2294 *stringtabs++ = t++;
2295 } while (--i);
2296 *stringtabs = NULL;
2297
e6f3862f
AP		 2298 /* stringtabs = vlabuf = d_stringtabs for later kfree */
2299 stringtabs = vla_ptr(vlabuf, d, stringtabs);
2300 t = vla_ptr(vlabuf, d, stringtab);
2301 s = vla_ptr(vlabuf, d, strings);
ddf8abd2
MN		 2302 strings = s;
2303 }
2304
2305 /* For each language */
2306 data += 16;
2307 len -= 16;
2308
2309 do { /* lang_count > 0 so we can use do-while */
2310 unsigned needed = needed_count;
2311
2312 if (unlikely(len < 3))
2313 goto error_free;
2314 t->language = get_unaligned_le16(data);
2315 t->strings = s;
2316 ++t;
2317
2318 data += 2;
2319 len -= 2;
2320
2321 /* For each string */
2322 do { /* str_count > 0 so we can use do-while */
2323 size_t length = strnlen(data, len);
2324
2325 if (unlikely(length == len))
2326 goto error_free;
2327
5ab54cf7
MN		 2328 /*
2329 * User may provide more strings then we need,
2330 * if that's the case we simply ignore the
2331 * rest
2332 */
ddf8abd2 2333 if (likely(needed)) {
5ab54cf7
MN		 2334 /*
2335 * s->id will be set while adding
ddf8abd2 2336 * function to configuration so for
5ab54cf7
MN		 2337 * now just leave garbage here.
2338 */
ddf8abd2
MN		 2339 s->s = data;
2340 --needed;
2341 ++s;
2342 }
2343
2344 data += length + 1;
2345 len -= length + 1;
2346 } while (--str_count);
2347
2348 s->id = 0; /* terminator */
2349 s->s = NULL;
2350 ++s;
2351
2352 } while (--lang_count);
2353
2354 /* Some garbage left? */
2355 if (unlikely(len))
2356 goto error_free;
2357
2358 /* Done! */
2359 ffs->stringtabs = stringtabs;
2360 ffs->raw_strings = _data;
2361
2362 return 0;
2363
2364error_free:
2365 kfree(stringtabs);
2366error:
2367 kfree(_data);
2368 return -EINVAL;
2369}
2370
2371
ddf8abd2
MN		 2372/* Events handling and management *******************************************/
2373
2374static void __ffs_event_add(struct ffs_data *ffs,
2375 enum usb_functionfs_event_type type)
2376{
2377 enum usb_functionfs_event_type rem_type1, rem_type2 = type;
2378 int neg = 0;
2379
5ab54cf7
MN		 2380 /*
2381 * Abort any unhandled setup
2382 *
2383 * We do not need to worry about some cmpxchg() changing value
ddf8abd2
MN		 2384 * of ffs->setup_state without holding the lock because when
2385 * state is FFS_SETUP_PENDING cmpxchg() in several places in
5ab54cf7
MN		 2386 * the source does nothing.
2387 */
ddf8abd2 2388 if (ffs->setup_state == FFS_SETUP_PENDING)
e46318a0 2389 ffs->setup_state = FFS_SETUP_CANCELLED;
ddf8abd2 2390
67913bbd
MN		 2391 /*
2392 * Logic of this function guarantees that there are at most four pending
2393 * evens on ffs->ev.types queue. This is important because the queue
2394 * has space for four elements only and __ffs_ep0_read_events function
2395 * depends on that limit as well. If more event types are added, those
2396 * limits have to be revisited or guaranteed to still hold.
2397 */
ddf8abd2
MN		 2398 switch (type) {
2399 case FUNCTIONFS_RESUME:
2400 rem_type2 = FUNCTIONFS_SUSPEND;
5ab54cf7 2401 /* FALL THROUGH */
ddf8abd2
MN		 2402 case FUNCTIONFS_SUSPEND:
2403 case FUNCTIONFS_SETUP:
2404 rem_type1 = type;
5ab54cf7 2405 /* Discard all similar events */
ddf8abd2
MN		 2406 break;
2407
2408 case FUNCTIONFS_BIND:
2409 case FUNCTIONFS_UNBIND:
2410 case FUNCTIONFS_DISABLE:
2411 case FUNCTIONFS_ENABLE:
5ab54cf7 2412 /* Discard everything other then power management. */
ddf8abd2
MN		 2413 rem_type1 = FUNCTIONFS_SUSPEND;
2414 rem_type2 = FUNCTIONFS_RESUME;
2415 neg = 1;
2416 break;
2417
2418 default:
fe00bcbf
MN		 2419 WARN(1, "%d: unknown event, this should not happen\n", type);
2420 return;
ddf8abd2
MN		 2421 }
2422
2423 {
2424 u8 *ev = ffs->ev.types, *out = ev;
2425 unsigned n = ffs->ev.count;
2426 for (; n; --n, ++ev)
2427 if ((*ev == rem_type1 || *ev == rem_type2) == neg)
2428 *out++ = *ev;
2429 else
aa02f172 2430 pr_vdebug("purging event %d\n", *ev);
ddf8abd2
MN		 2431 ffs->ev.count = out - ffs->ev.types;
2432 }
2433
aa02f172 2434 pr_vdebug("adding event %d\n", type);
ddf8abd2
MN		 2435 ffs->ev.types[ffs->ev.count++] = type;
2436 wake_up_locked(&ffs->ev.waitq);
5e33f6fd
RB		 2437 if (ffs->ffs_eventfd)
2438 eventfd_signal(ffs->ffs_eventfd, 1);
ddf8abd2
MN		 2439}
2440
2441static void ffs_event_add(struct ffs_data *ffs,
2442 enum usb_functionfs_event_type type)
2443{
2444 unsigned long flags;
2445 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
2446 __ffs_event_add(ffs, type);
2447 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
2448}
2449
ddf8abd2
MN		 2450/* Bind/unbind USB function hooks *******************************************/
2451
6d5c1c77
RB		 2452static int ffs_ep_addr2idx(struct ffs_data *ffs, u8 endpoint_address)
2453{
2454 int i;
2455
2456 for (i = 1; i < ARRAY_SIZE(ffs->eps_addrmap); ++i)
2457 if (ffs->eps_addrmap[i] == endpoint_address)
2458 return i;
2459 return -ENOENT;
2460}
2461
ddf8abd2
MN		 2462static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
2463 struct usb_descriptor_header *desc,
2464 void *priv)
2465{
2466 struct usb_endpoint_descriptor *ds = (void *)desc;
2467 struct ffs_function *func = priv;
2468 struct ffs_ep *ffs_ep;
85b06f5e
DC		 2469 unsigned ep_desc_id;
2470 int idx;
8d4e897b 2471 static const char *speed_names[] = { "full", "high", "super" };
ddf8abd2
MN		 2472
2473 if (type != FFS_DESCRIPTOR)
2474 return 0;
2475
8d4e897b
MG		 2476 /*
2477 * If ss_descriptors is not NULL, we are reading super speed
2478 * descriptors; if hs_descriptors is not NULL, we are reading high
2479 * speed descriptors; otherwise, we are reading full speed
2480 * descriptors.
2481 */
2482 if (func->function.ss_descriptors) {
2483 ep_desc_id = 2;
2484 func->function.ss_descriptors[(long)valuep] = desc;
2485 } else if (func->function.hs_descriptors) {
2486 ep_desc_id = 1;
ddf8abd2 2487 func->function.hs_descriptors[(long)valuep] = desc;
8d4e897b
MG		 2488 } else {
2489 ep_desc_id = 0;
10287bae 2490 func->function.fs_descriptors[(long)valuep] = desc;
8d4e897b 2491 }
ddf8abd2
MN		 2492
2493 if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT)
2494 return 0;
2495
6d5c1c77
RB		 2496 idx = ffs_ep_addr2idx(func->ffs, ds->bEndpointAddress) - 1;
2497 if (idx < 0)
2498 return idx;
2499
ddf8abd2
MN		 2500 ffs_ep = func->eps + idx;
2501
8d4e897b
MG		 2502 if (unlikely(ffs_ep->descs[ep_desc_id])) {
2503 pr_err("two %sspeed descriptors for EP %d\n",
2504 speed_names[ep_desc_id],
d8df0b61 2505 ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
ddf8abd2
MN		 2506 return -EINVAL;
2507 }
8d4e897b 2508 ffs_ep->descs[ep_desc_id] = ds;
ddf8abd2
MN		 2509
2510 ffs_dump_mem(": Original ep desc", ds, ds->bLength);
2511 if (ffs_ep->ep) {
2512 ds->bEndpointAddress = ffs_ep->descs[0]->bEndpointAddress;
2513 if (!ds->wMaxPacketSize)
2514 ds->wMaxPacketSize = ffs_ep->descs[0]->wMaxPacketSize;
2515 } else {
2516 struct usb_request *req;
2517 struct usb_ep *ep;
1b0bf88f 2518 u8 bEndpointAddress;
ddf8abd2 2519
1b0bf88f
RB		 2520 /*
2521 * We back up bEndpointAddress because autoconfig overwrites
2522 * it with physical endpoint address.
2523 */
2524 bEndpointAddress = ds->bEndpointAddress;
aa02f172 2525 pr_vdebug("autoconfig\n");
ddf8abd2
MN		 2526 ep = usb_ep_autoconfig(func->gadget, ds);
2527 if (unlikely(!ep))
2528 return -ENOTSUPP;
cc7e6056 2529 ep->driver_data = func->eps + idx;
ddf8abd2
MN		 2530
2531 req = usb_ep_alloc_request(ep, GFP_KERNEL);
2532 if (unlikely(!req))
2533 return -ENOMEM;
2534
2535 ffs_ep->ep = ep;
2536 ffs_ep->req = req;
2537 func->eps_revmap[ds->bEndpointAddress &
2538 USB_ENDPOINT_NUMBER_MASK] = idx + 1;
1b0bf88f
RB		 2539 /*
2540 * If we use virtual address mapping, we restore
2541 * original bEndpointAddress value.
2542 */
2543 if (func->ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
2544 ds->bEndpointAddress = bEndpointAddress;
ddf8abd2
MN		 2545 }
2546 ffs_dump_mem(": Rewritten ep desc", ds, ds->bLength);
2547
2548 return 0;
2549}
2550
ddf8abd2
MN		 2551static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
2552 struct usb_descriptor_header *desc,
2553 void *priv)
2554{
2555 struct ffs_function *func = priv;
2556 unsigned idx;
2557 u8 newValue;
2558
2559 switch (type) {
2560 default:
2561 case FFS_DESCRIPTOR:
2562 /* Handled in previous pass by __ffs_func_bind_do_descs() */
2563 return 0;
2564
2565 case FFS_INTERFACE:
2566 idx = *valuep;
2567 if (func->interfaces_nums[idx] < 0) {
2568 int id = usb_interface_id(func->conf, &func->function);
2569 if (unlikely(id < 0))
2570 return id;
2571 func->interfaces_nums[idx] = id;
2572 }
2573 newValue = func->interfaces_nums[idx];
2574 break;
2575
2576 case FFS_STRING:
2577 /* String' IDs are allocated when fsf_data is bound to cdev */
2578 newValue = func->ffs->stringtabs[0]->strings[*valuep - 1].id;
2579 break;
2580
2581 case FFS_ENDPOINT:
5ab54cf7
MN		 2582 /*
2583 * USB_DT_ENDPOINT are handled in
2584 * __ffs_func_bind_do_descs().
2585 */
ddf8abd2
MN		 2586 if (desc->bDescriptorType == USB_DT_ENDPOINT)
2587 return 0;
2588
2589 idx = (*valuep & USB_ENDPOINT_NUMBER_MASK) - 1;
2590 if (unlikely(!func->eps[idx].ep))
2591 return -EINVAL;
2592
2593 {
2594 struct usb_endpoint_descriptor **descs;
2595 descs = func->eps[idx].descs;
2596 newValue = descs[descs[0] ? 0 : 1]->bEndpointAddress;
2597 }
2598 break;
2599 }
2600
aa02f172 2601 pr_vdebug("%02x -> %02x\n", *valuep, newValue);
ddf8abd2
MN		 2602 *valuep = newValue;
2603 return 0;
2604}
2605
f0175ab5
AP		 2606static int __ffs_func_bind_do_os_desc(enum ffs_os_desc_type type,
2607 struct usb_os_desc_header *h, void *data,
2608 unsigned len, void *priv)
2609{
2610 struct ffs_function *func = priv;
2611 u8 length = 0;
2612
2613 switch (type) {
2614 case FFS_OS_DESC_EXT_COMPAT: {
2615 struct usb_ext_compat_desc *desc = data;
2616 struct usb_os_desc_table *t;
2617
2618 t = &func->function.os_desc_table[desc->bFirstInterfaceNumber];
2619 t->if_id = func->interfaces_nums[desc->bFirstInterfaceNumber];
2620 memcpy(t->os_desc->ext_compat_id, &desc->CompatibleID,
2621 ARRAY_SIZE(desc->CompatibleID) +
2622 ARRAY_SIZE(desc->SubCompatibleID));
2623 length = sizeof(*desc);
2624 }
2625 break;
2626 case FFS_OS_DESC_EXT_PROP: {
2627 struct usb_ext_prop_desc *desc = data;
2628 struct usb_os_desc_table *t;
2629 struct usb_os_desc_ext_prop *ext_prop;
2630 char *ext_prop_name;
2631 char *ext_prop_data;
2632
2633 t = &func->function.os_desc_table[h->interface];
2634 t->if_id = func->interfaces_nums[h->interface];
2635
2636 ext_prop = func->ffs->ms_os_descs_ext_prop_avail;
2637 func->ffs->ms_os_descs_ext_prop_avail += sizeof(*ext_prop);
2638
2639 ext_prop->type = le32_to_cpu(desc->dwPropertyDataType);
2640 ext_prop->name_len = le16_to_cpu(desc->wPropertyNameLength);
2641 ext_prop->data_len = le32_to_cpu(*(u32 *)
2642 usb_ext_prop_data_len_ptr(data, ext_prop->name_len));
2643 length = ext_prop->name_len + ext_prop->data_len + 14;
2644
2645 ext_prop_name = func->ffs->ms_os_descs_ext_prop_name_avail;
2646 func->ffs->ms_os_descs_ext_prop_name_avail +=
2647 ext_prop->name_len;
2648
2649 ext_prop_data = func->ffs->ms_os_descs_ext_prop_data_avail;
2650 func->ffs->ms_os_descs_ext_prop_data_avail +=
2651 ext_prop->data_len;
2652 memcpy(ext_prop_data,
2653 usb_ext_prop_data_ptr(data, ext_prop->name_len),
2654 ext_prop->data_len);
2655 /* unicode data reported to the host as "WCHAR"s */
2656 switch (ext_prop->type) {
2657 case USB_EXT_PROP_UNICODE:
2658 case USB_EXT_PROP_UNICODE_ENV:
2659 case USB_EXT_PROP_UNICODE_LINK:
2660 case USB_EXT_PROP_UNICODE_MULTI:
2661 ext_prop->data_len *= 2;
2662 break;
2663 }
2664 ext_prop->data = ext_prop_data;
2665
2666 memcpy(ext_prop_name, usb_ext_prop_name_ptr(data),
2667 ext_prop->name_len);
2668 /* property name reported to the host as "WCHAR"s */
2669 ext_prop->name_len *= 2;
2670 ext_prop->name = ext_prop_name;
2671
2672 t->os_desc->ext_prop_len +=
2673 ext_prop->name_len + ext_prop->data_len + 14;
2674 ++t->os_desc->ext_prop_count;
2675 list_add_tail(&ext_prop->entry, &t->os_desc->ext_prop);
2676 }
2677 break;
2678 default:
2679 pr_vdebug("unknown descriptor: %d\n", type);
2680 }
2681
2682 return length;
2683}
2684
5920cda6
AP		 2685static inline struct f_fs_opts *ffs_do_functionfs_bind(struct usb_function *f,
2686 struct usb_configuration *c)
2687{
2688 struct ffs_function *func = ffs_func_from_usb(f);
2689 struct f_fs_opts *ffs_opts =
2690 container_of(f->fi, struct f_fs_opts, func_inst);
2691 int ret;
2692
2693 ENTER();
2694
2695 /*
2696 * Legacy gadget triggers binding in functionfs_ready_callback,
2697 * which already uses locking; taking the same lock here would
2698 * cause a deadlock.
2699 *
2700 * Configfs-enabled gadgets however do need ffs_dev_lock.
2701 */
2702 if (!ffs_opts->no_configfs)
2703 ffs_dev_lock();
2704 ret = ffs_opts->dev->desc_ready ? 0 : -ENODEV;
2705 func->ffs = ffs_opts->dev->ffs_data;
2706 if (!ffs_opts->no_configfs)
2707 ffs_dev_unlock();
2708 if (ret)
2709 return ERR_PTR(ret);
2710
2711 func->conf = c;
2712 func->gadget = c->cdev->gadget;
2713
5920cda6
AP		 2714 /*
2715 * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
2716 * configurations are bound in sequence with list_for_each_entry,
2717 * in each configuration its functions are bound in sequence
2718 * with list_for_each_entry, so we assume no race condition
2719 * with regard to ffs_opts->bound access
2720 */
2721 if (!ffs_opts->refcnt) {
2722 ret = functionfs_bind(func->ffs, c->cdev);
2723 if (ret)
2724 return ERR_PTR(ret);
2725 }
2726 ffs_opts->refcnt++;
2727 func->function.strings = func->ffs->stringtabs;
2728
2729 return ffs_opts;
2730}
5920cda6
AP		 2731
2732static int _ffs_func_bind(struct usb_configuration *c,
2733 struct usb_function *f)
ddf8abd2
MN		 2734{
2735 struct ffs_function *func = ffs_func_from_usb(f);
2736 struct ffs_data *ffs = func->ffs;
2737
2738 const int full = !!func->ffs->fs_descs_count;
2739 const int high = gadget_is_dualspeed(func->gadget) &&
2740 func->ffs->hs_descs_count;
8d4e897b
MG		 2741 const int super = gadget_is_superspeed(func->gadget) &&
2742 func->ffs->ss_descs_count;
ddf8abd2 2743
f0175ab5 2744 int fs_len, hs_len, ss_len, ret, i;
ddf8abd2
MN		 2745
2746 /* Make it a single chunk, less management later on */
e6f3862f
AP		 2747 vla_group(d);
2748 vla_item_with_sz(d, struct ffs_ep, eps, ffs->eps_count);
2749 vla_item_with_sz(d, struct usb_descriptor_header *, fs_descs,
2750 full ? ffs->fs_descs_count + 1 : 0);
2751 vla_item_with_sz(d, struct usb_descriptor_header *, hs_descs,
2752 high ? ffs->hs_descs_count + 1 : 0);
8d4e897b
MG		 2753 vla_item_with_sz(d, struct usb_descriptor_header *, ss_descs,
2754 super ? ffs->ss_descs_count + 1 : 0);
e6f3862f 2755 vla_item_with_sz(d, short, inums, ffs->interfaces_count);
f0175ab5
AP		 2756 vla_item_with_sz(d, struct usb_os_desc_table, os_desc_table,
2757 c->cdev->use_os_string ? ffs->interfaces_count : 0);
2758 vla_item_with_sz(d, char[16], ext_compat,
2759 c->cdev->use_os_string ? ffs->interfaces_count : 0);
2760 vla_item_with_sz(d, struct usb_os_desc, os_desc,
2761 c->cdev->use_os_string ? ffs->interfaces_count : 0);
2762 vla_item_with_sz(d, struct usb_os_desc_ext_prop, ext_prop,
2763 ffs->ms_os_descs_ext_prop_count);
2764 vla_item_with_sz(d, char, ext_prop_name,
2765 ffs->ms_os_descs_ext_prop_name_len);
2766 vla_item_with_sz(d, char, ext_prop_data,
2767 ffs->ms_os_descs_ext_prop_data_len);
ac8dde11 2768 vla_item_with_sz(d, char, raw_descs, ffs->raw_descs_length);
e6f3862f 2769 char *vlabuf;
ddf8abd2
MN		 2770
2771 ENTER();
2772
8d4e897b
MG		 2773 /* Has descriptors only for speeds gadget does not support */
2774 if (unlikely(!(full | high | super)))
ddf8abd2
MN		 2775 return -ENOTSUPP;
2776
e6f3862f 2777 /* Allocate a single chunk, less management later on */
f0175ab5 2778 vlabuf = kzalloc(vla_group_size(d), GFP_KERNEL);
e6f3862f 2779 if (unlikely(!vlabuf))
ddf8abd2
MN		 2780 return -ENOMEM;
2781
f0175ab5
AP		 2782 ffs->ms_os_descs_ext_prop_avail = vla_ptr(vlabuf, d, ext_prop);
2783 ffs->ms_os_descs_ext_prop_name_avail =
2784 vla_ptr(vlabuf, d, ext_prop_name);
2785 ffs->ms_os_descs_ext_prop_data_avail =
2786 vla_ptr(vlabuf, d, ext_prop_data);
2787
ac8dde11
MN		 2788 /* Copy descriptors */
2789 memcpy(vla_ptr(vlabuf, d, raw_descs), ffs->raw_descs,
2790 ffs->raw_descs_length);
8d4e897b 2791
e6f3862f
AP		 2792 memset(vla_ptr(vlabuf, d, inums), 0xff, d_inums__sz);
2793 for (ret = ffs->eps_count; ret; --ret) {
2794 struct ffs_ep *ptr;
2795
2796 ptr = vla_ptr(vlabuf, d, eps);
2797 ptr[ret].num = -1;
2798 }
ddf8abd2 2799
e6f3862f
AP		 2800 /* Save pointers
2801 * d_eps == vlabuf, func->eps used to kfree vlabuf later
2802 */
2803 func->eps = vla_ptr(vlabuf, d, eps);
2804 func->interfaces_nums = vla_ptr(vlabuf, d, inums);
ddf8abd2 2805
5ab54cf7
MN		 2806 /*
2807 * Go through all the endpoint descriptors and allocate
ddf8abd2 2808 * endpoints first, so that later we can rewrite the endpoint
5ab54cf7
MN		 2809 * numbers without worrying that it may be described later on.
2810 */
ddf8abd2 2811 if (likely(full)) {
e6f3862f 2812 func->function.fs_descriptors = vla_ptr(vlabuf, d, fs_descs);
8d4e897b
MG		 2813 fs_len = ffs_do_descs(ffs->fs_descs_count,
2814 vla_ptr(vlabuf, d, raw_descs),
2815 d_raw_descs__sz,
2816 __ffs_func_bind_do_descs, func);
2817 if (unlikely(fs_len < 0)) {
2818 ret = fs_len;
ddf8abd2 2819 goto error;
8d4e897b 2820 }
ddf8abd2 2821 } else {
8d4e897b 2822 fs_len = 0;
ddf8abd2
MN		 2823 }
2824
2825 if (likely(high)) {
e6f3862f 2826 func->function.hs_descriptors = vla_ptr(vlabuf, d, hs_descs);
8d4e897b
MG		 2827 hs_len = ffs_do_descs(ffs->hs_descs_count,
2828 vla_ptr(vlabuf, d, raw_descs) + fs_len,
2829 d_raw_descs__sz - fs_len,
2830 __ffs_func_bind_do_descs, func);
2831 if (unlikely(hs_len < 0)) {
2832 ret = hs_len;
2833 goto error;
2834 }
2835 } else {
2836 hs_len = 0;
2837 }
2838
2839 if (likely(super)) {
2840 func->function.ss_descriptors = vla_ptr(vlabuf, d, ss_descs);
f0175ab5 2841 ss_len = ffs_do_descs(ffs->ss_descs_count,
8d4e897b
MG		 2842 vla_ptr(vlabuf, d, raw_descs) + fs_len + hs_len,
2843 d_raw_descs__sz - fs_len - hs_len,
2844 __ffs_func_bind_do_descs, func);
f0175ab5
AP		 2845 if (unlikely(ss_len < 0)) {
2846 ret = ss_len;
8854894c 2847 goto error;
f0175ab5
AP		 2848 }
2849 } else {
2850 ss_len = 0;
ddf8abd2
MN		 2851 }
2852
5ab54cf7
MN		 2853 /*
2854 * Now handle interface numbers allocation and interface and
2855 * endpoint numbers rewriting. We can do that in one go
2856 * now.
2857 */
ddf8abd2 2858 ret = ffs_do_descs(ffs->fs_descs_count +
8d4e897b
MG		 2859 (high ? ffs->hs_descs_count : 0) +
2860 (super ? ffs->ss_descs_count : 0),
e6f3862f 2861 vla_ptr(vlabuf, d, raw_descs), d_raw_descs__sz,
ddf8abd2
MN		 2862 __ffs_func_bind_do_nums, func);
2863 if (unlikely(ret < 0))
2864 goto error;
2865
f0175ab5
AP		 2866 func->function.os_desc_table = vla_ptr(vlabuf, d, os_desc_table);
2867 if (c->cdev->use_os_string)
2868 for (i = 0; i < ffs->interfaces_count; ++i) {
2869 struct usb_os_desc *desc;
2870
2871 desc = func->function.os_desc_table[i].os_desc =
2872 vla_ptr(vlabuf, d, os_desc) +
2873 i * sizeof(struct usb_os_desc);
2874 desc->ext_compat_id =
2875 vla_ptr(vlabuf, d, ext_compat) + i * 16;
2876 INIT_LIST_HEAD(&desc->ext_prop);
2877 }
2878 ret = ffs_do_os_descs(ffs->ms_os_descs_count,
2879 vla_ptr(vlabuf, d, raw_descs) +
2880 fs_len + hs_len + ss_len,
2881 d_raw_descs__sz - fs_len - hs_len - ss_len,
2882 __ffs_func_bind_do_os_desc, func);
2883 if (unlikely(ret < 0))
2884 goto error;
2885 func->function.os_desc_n =
2886 c->cdev->use_os_string ? ffs->interfaces_count : 0;
2887
ddf8abd2
MN		 2888 /* And we're done */
2889 ffs_event_add(ffs, FUNCTIONFS_BIND);
2890 return 0;
2891
2892error:
2893 /* XXX Do we need to release all claimed endpoints here? */
2894 return ret;
2895}
2896
5920cda6
AP		 2897static int ffs_func_bind(struct usb_configuration *c,
2898 struct usb_function *f)
2899{
5920cda6
AP		 2900 struct f_fs_opts *ffs_opts = ffs_do_functionfs_bind(f, c);
2901
2902 if (IS_ERR(ffs_opts))
2903 return PTR_ERR(ffs_opts);
5920cda6
AP		 2904
2905 return _ffs_func_bind(c, f);
2906}
2907
ddf8abd2
MN		 2908
2909/* Other USB function hooks *************************************************/
2910
18d6b32f
RB		 2911static void ffs_reset_work(struct work_struct *work)
2912{
2913 struct ffs_data *ffs = container_of(work,
2914 struct ffs_data, reset_work);
2915 ffs_data_reset(ffs);
2916}
2917
ddf8abd2
MN		 2918static int ffs_func_set_alt(struct usb_function *f,
2919 unsigned interface, unsigned alt)
2920{
2921 struct ffs_function *func = ffs_func_from_usb(f);
2922 struct ffs_data *ffs = func->ffs;
2923 int ret = 0, intf;
2924
2925 if (alt != (unsigned)-1) {
2926 intf = ffs_func_revmap_intf(func, interface);
2927 if (unlikely(intf < 0))
2928 return intf;
2929 }
2930
2931 if (ffs->func)
2932 ffs_func_eps_disable(ffs->func);
2933
18d6b32f
RB		 2934 if (ffs->state == FFS_DEACTIVATED) {
2935 ffs->state = FFS_CLOSING;
2936 INIT_WORK(&ffs->reset_work, ffs_reset_work);
2937 schedule_work(&ffs->reset_work);
2938 return -ENODEV;
2939 }
2940
ddf8abd2
MN		 2941 if (ffs->state != FFS_ACTIVE)
2942 return -ENODEV;
2943
2944 if (alt == (unsigned)-1) {
2945 ffs->func = NULL;
2946 ffs_event_add(ffs, FUNCTIONFS_DISABLE);
2947 return 0;
2948 }
2949
2950 ffs->func = func;
2951 ret = ffs_func_eps_enable(func);
2952 if (likely(ret >= 0))
2953 ffs_event_add(ffs, FUNCTIONFS_ENABLE);
2954 return ret;
2955}
2956
2957static void ffs_func_disable(struct usb_function *f)
2958{
2959 ffs_func_set_alt(f, 0, (unsigned)-1);
2960}
2961
2962static int ffs_func_setup(struct usb_function *f,
2963 const struct usb_ctrlrequest *creq)
2964{
2965 struct ffs_function *func = ffs_func_from_usb(f);
2966 struct ffs_data *ffs = func->ffs;
2967 unsigned long flags;
2968 int ret;
2969
2970 ENTER();
2971
aa02f172
MN		 2972 pr_vdebug("creq->bRequestType = %02x\n", creq->bRequestType);
2973 pr_vdebug("creq->bRequest = %02x\n", creq->bRequest);
2974 pr_vdebug("creq->wValue = %04x\n", le16_to_cpu(creq->wValue));
2975 pr_vdebug("creq->wIndex = %04x\n", le16_to_cpu(creq->wIndex));
2976 pr_vdebug("creq->wLength = %04x\n", le16_to_cpu(creq->wLength));
ddf8abd2 2977
5ab54cf7
MN		 2978 /*
2979 * Most requests directed to interface go through here
ddf8abd2
MN		 2980 * (notable exceptions are set/get interface) so we need to
2981 * handle them. All other either handled by composite or
2982 * passed to usb_configuration->setup() (if one is set). No
2983 * matter, we will handle requests directed to endpoint here
2984 * as well (as it's straightforward) but what to do with any
5ab54cf7
MN		 2985 * other request?
2986 */
ddf8abd2
MN		 2987 if (ffs->state != FFS_ACTIVE)
2988 return -ENODEV;
2989
2990 switch (creq->bRequestType & USB_RECIP_MASK) {
2991 case USB_RECIP_INTERFACE:
2992 ret = ffs_func_revmap_intf(func, le16_to_cpu(creq->wIndex));
2993 if (unlikely(ret < 0))
2994 return ret;
2995 break;
2996
2997 case USB_RECIP_ENDPOINT:
2998 ret = ffs_func_revmap_ep(func, le16_to_cpu(creq->wIndex));
2999 if (unlikely(ret < 0))
3000 return ret;
1b0bf88f
RB		 3001 if (func->ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
3002 ret = func->ffs->eps_addrmap[ret];
ddf8abd2
MN		 3003 break;
3004
3005 default:
3006 return -EOPNOTSUPP;
3007 }
3008
3009 spin_lock_irqsave(&ffs->ev.waitq.lock, flags);
3010 ffs->ev.setup = *creq;
3011 ffs->ev.setup.wIndex = cpu_to_le16(ret);
3012 __ffs_event_add(ffs, FUNCTIONFS_SETUP);
3013 spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
3014
3015 return 0;
3016}
3017
3018static void ffs_func_suspend(struct usb_function *f)
3019{
3020 ENTER();
3021 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_SUSPEND);
3022}
3023
3024static void ffs_func_resume(struct usb_function *f)
3025{
3026 ENTER();
3027 ffs_event_add(ffs_func_from_usb(f)->ffs, FUNCTIONFS_RESUME);
3028}
3029
3030
5ab54cf7 3031/* Endpoint and interface numbers reverse mapping ***************************/
ddf8abd2
MN		 3032
3033static int ffs_func_revmap_ep(struct ffs_function *func, u8 num)
3034{
3035 num = func->eps_revmap[num & USB_ENDPOINT_NUMBER_MASK];
3036 return num ? num : -EDOM;
3037}
3038
3039static int ffs_func_revmap_intf(struct ffs_function *func, u8 intf)
3040{
3041 short *nums = func->interfaces_nums;
3042 unsigned count = func->ffs->interfaces_count;
3043
3044 for (; count; --count, ++nums) {
3045 if (*nums >= 0 && *nums == intf)
3046 return nums - func->interfaces_nums;
3047 }
3048
3049 return -EDOM;
3050}
3051
3052
4b187fce
AP		 3053/* Devices management *******************************************************/
3054
3055static LIST_HEAD(ffs_devices);
3056
da13a773 3057static struct ffs_dev *_ffs_do_find_dev(const char *name)
4b187fce
AP		 3058{
3059 struct ffs_dev *dev;
3060
3061 list_for_each_entry(dev, &ffs_devices, entry) {
3062 if (!dev->name || !name)
3063 continue;
3064 if (strcmp(dev->name, name) == 0)
3065 return dev;
3066 }
b658499f 3067
4b187fce
AP		 3068 return NULL;
3069}
3070
3071/*
3072 * ffs_lock must be taken by the caller of this function
3073 */
da13a773 3074static struct ffs_dev *_ffs_get_single_dev(void)
4b187fce
AP		 3075{
3076 struct ffs_dev *dev;
3077
3078 if (list_is_singular(&ffs_devices)) {
3079 dev = list_first_entry(&ffs_devices, struct ffs_dev, entry);
3080 if (dev->single)
3081 return dev;
3082 }
3083
3084 return NULL;
3085}
3086
3087/*
3088 * ffs_lock must be taken by the caller of this function
3089 */
da13a773 3090static struct ffs_dev *_ffs_find_dev(const char *name)
4b187fce
AP		 3091{
3092 struct ffs_dev *dev;
3093
da13a773 3094 dev = _ffs_get_single_dev();
4b187fce
AP		 3095 if (dev)
3096 return dev;
3097
da13a773 3098 return _ffs_do_find_dev(name);
4b187fce
AP		 3099}
3100
b658499f
AP		 3101/* Configfs support *********************************************************/
3102
3103static inline struct f_fs_opts *to_ffs_opts(struct config_item *item)
3104{
3105 return container_of(to_config_group(item), struct f_fs_opts,
3106 func_inst.group);
3107}
3108
3109static void ffs_attr_release(struct config_item *item)
3110{
3111 struct f_fs_opts *opts = to_ffs_opts(item);
3112
3113 usb_put_function_instance(&opts->func_inst);
3114}
3115
3116static struct configfs_item_operations ffs_item_ops = {
3117 .release = ffs_attr_release,
3118};
3119
3120static struct config_item_type ffs_func_type = {
3121 .ct_item_ops = &ffs_item_ops,
3122 .ct_owner = THIS_MODULE,
3123};
3124
3125
5920cda6
AP		 3126/* Function registration interface ******************************************/
3127
5920cda6
AP		 3128static void ffs_free_inst(struct usb_function_instance *f)
3129{
3130 struct f_fs_opts *opts;
3131
3132 opts = to_f_fs_opts(f);
3133 ffs_dev_lock();
da13a773 3134 _ffs_free_dev(opts->dev);
5920cda6
AP		 3135 ffs_dev_unlock();
3136 kfree(opts);
3137}
3138
b658499f
AP		 3139#define MAX_INST_NAME_LEN 40
3140
3141static int ffs_set_inst_name(struct usb_function_instance *fi, const char *name)
3142{
3143 struct f_fs_opts *opts;
3144 char *ptr;
3145 const char *tmp;
3146 int name_len, ret;
3147
3148 name_len = strlen(name) + 1;
3149 if (name_len > MAX_INST_NAME_LEN)
3150 return -ENAMETOOLONG;
3151
3152 ptr = kstrndup(name, name_len, GFP_KERNEL);
3153 if (!ptr)
3154 return -ENOMEM;
3155
3156 opts = to_f_fs_opts(fi);
3157 tmp = NULL;
3158
3159 ffs_dev_lock();
3160
3161 tmp = opts->dev->name_allocated ? opts->dev->name : NULL;
3162 ret = _ffs_name_dev(opts->dev, ptr);
3163 if (ret) {
3164 kfree(ptr);
3165 ffs_dev_unlock();
3166 return ret;
3167 }
3168 opts->dev->name_allocated = true;
3169
3170 ffs_dev_unlock();
3171
3172 kfree(tmp);
3173
3174 return 0;
3175}
3176
5920cda6
AP		 3177static struct usb_function_instance *ffs_alloc_inst(void)
3178{
3179 struct f_fs_opts *opts;
3180 struct ffs_dev *dev;
3181
3182 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
3183 if (!opts)
3184 return ERR_PTR(-ENOMEM);
3185
b658499f 3186 opts->func_inst.set_inst_name = ffs_set_inst_name;
5920cda6
AP		 3187 opts->func_inst.free_func_inst = ffs_free_inst;
3188 ffs_dev_lock();
da13a773 3189 dev = _ffs_alloc_dev();
5920cda6
AP		 3190 ffs_dev_unlock();
3191 if (IS_ERR(dev)) {
3192 kfree(opts);
3193 return ERR_CAST(dev);
3194 }
3195 opts->dev = dev;
b658499f 3196 dev->opts = opts;
5920cda6 3197
b658499f
AP		 3198 config_group_init_type_name(&opts->func_inst.group, "",
3199 &ffs_func_type);
5920cda6
AP		 3200 return &opts->func_inst;
3201}
3202
3203static void ffs_free(struct usb_function *f)
3204{
3205 kfree(ffs_func_from_usb(f));
3206}
3207
3208static void ffs_func_unbind(struct usb_configuration *c,
3209 struct usb_function *f)
3210{
3211 struct ffs_function *func = ffs_func_from_usb(f);
3212 struct ffs_data *ffs = func->ffs;
3213 struct f_fs_opts *opts =
3214 container_of(f->fi, struct f_fs_opts, func_inst);
3215 struct ffs_ep *ep = func->eps;
3216 unsigned count = ffs->eps_count;
3217 unsigned long flags;
3218
3219 ENTER();
3220 if (ffs->func == func) {
3221 ffs_func_eps_disable(func);
3222 ffs->func = NULL;
3223 }
3224
3225 if (!--opts->refcnt)
3226 functionfs_unbind(ffs);
3227
3228 /* cleanup after autoconfig */
3229 spin_lock_irqsave(&func->ffs->eps_lock, flags);
3230 do {
3231 if (ep->ep && ep->req)
3232 usb_ep_free_request(ep->ep, ep->req);
3233 ep->req = NULL;
3234 ++ep;
3235 } while (--count);
3236 spin_unlock_irqrestore(&func->ffs->eps_lock, flags);
3237 kfree(func->eps);
3238 func->eps = NULL;
3239 /*
3240 * eps, descriptors and interfaces_nums are allocated in the
3241 * same chunk so only one free is required.
3242 */
3243 func->function.fs_descriptors = NULL;
3244 func->function.hs_descriptors = NULL;
8d4e897b 3245 func->function.ss_descriptors = NULL;
5920cda6
AP		 3246 func->interfaces_nums = NULL;
3247
3248 ffs_event_add(ffs, FUNCTIONFS_UNBIND);
3249}
3250
3251static struct usb_function *ffs_alloc(struct usb_function_instance *fi)
3252{
3253 struct ffs_function *func;
3254
3255 ENTER();
3256
3257 func = kzalloc(sizeof(*func), GFP_KERNEL);
3258 if (unlikely(!func))
3259 return ERR_PTR(-ENOMEM);
3260
3261 func->function.name = "Function FS Gadget";
3262
3263 func->function.bind = ffs_func_bind;
3264 func->function.unbind = ffs_func_unbind;
3265 func->function.set_alt = ffs_func_set_alt;
3266 func->function.disable = ffs_func_disable;
3267 func->function.setup = ffs_func_setup;
3268 func->function.suspend = ffs_func_suspend;
3269 func->function.resume = ffs_func_resume;
3270 func->function.free_func = ffs_free;
3271
3272 return &func->function;
3273}
3274
4b187fce
AP		 3275/*
3276 * ffs_lock must be taken by the caller of this function
3277 */
da13a773 3278static struct ffs_dev *_ffs_alloc_dev(void)
4b187fce
AP		 3279{
3280 struct ffs_dev *dev;
3281 int ret;
3282
da13a773 3283 if (_ffs_get_single_dev())
4b187fce
AP		 3284 return ERR_PTR(-EBUSY);
3285
3286 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
3287 if (!dev)
3288 return ERR_PTR(-ENOMEM);
3289
3290 if (list_empty(&ffs_devices)) {
3291 ret = functionfs_init();
3292 if (ret) {
3293 kfree(dev);
3294 return ERR_PTR(ret);
3295 }
3296 }
3297
3298 list_add(&dev->entry, &ffs_devices);
3299
3300 return dev;
3301}
3302
3303/*
3304 * ffs_lock must be taken by the caller of this function
3305 * The caller is responsible for "name" being available whenever f_fs needs it
3306 */
3307static int _ffs_name_dev(struct ffs_dev *dev, const char *name)
3308{
3309 struct ffs_dev *existing;
3310
da13a773 3311 existing = _ffs_do_find_dev(name);
4b187fce
AP		 3312 if (existing)
3313 return -EBUSY;
ab13cb0c 3314
4b187fce
AP		 3315 dev->name = name;
3316
3317 return 0;
3318}
3319
3320/*
3321 * The caller is responsible for "name" being available whenever f_fs needs it
3322 */
3323int ffs_name_dev(struct ffs_dev *dev, const char *name)
3324{
3325 int ret;
3326
3327 ffs_dev_lock();
3328 ret = _ffs_name_dev(dev, name);
3329 ffs_dev_unlock();
3330
3331 return ret;
3332}
0700faaf 3333EXPORT_SYMBOL_GPL(ffs_name_dev);
4b187fce
AP		 3334
3335int ffs_single_dev(struct ffs_dev *dev)
3336{
3337 int ret;
3338
3339 ret = 0;
3340 ffs_dev_lock();
3341
3342 if (!list_is_singular(&ffs_devices))
3343 ret = -EBUSY;
3344 else
3345 dev->single = true;
3346
3347 ffs_dev_unlock();
3348 return ret;
3349}
0700faaf 3350EXPORT_SYMBOL_GPL(ffs_single_dev);
4b187fce
AP		 3351
3352/*
3353 * ffs_lock must be taken by the caller of this function
3354 */
da13a773 3355static void _ffs_free_dev(struct ffs_dev *dev)
4b187fce
AP		 3356{
3357 list_del(&dev->entry);
b658499f
AP		 3358 if (dev->name_allocated)
3359 kfree(dev->name);
4b187fce
AP		 3360 kfree(dev);
3361 if (list_empty(&ffs_devices))
3362 functionfs_cleanup();
3363}
3364
3365static void *ffs_acquire_dev(const char *dev_name)
3366{
3367 struct ffs_dev *ffs_dev;
3368
3369 ENTER();
3370 ffs_dev_lock();
3371
da13a773 3372 ffs_dev = _ffs_find_dev(dev_name);
4b187fce 3373 if (!ffs_dev)
d668b4f3 3374 ffs_dev = ERR_PTR(-ENOENT);
4b187fce
AP		 3375 else if (ffs_dev->mounted)
3376 ffs_dev = ERR_PTR(-EBUSY);
5920cda6
AP		 3377 else if (ffs_dev->ffs_acquire_dev_callback &&
3378 ffs_dev->ffs_acquire_dev_callback(ffs_dev))
d668b4f3 3379 ffs_dev = ERR_PTR(-ENOENT);
4b187fce
AP		 3380 else
3381 ffs_dev->mounted = true;
3382
3383 ffs_dev_unlock();
3384 return ffs_dev;
3385}
3386
3387static void ffs_release_dev(struct ffs_data *ffs_data)
3388{
3389 struct ffs_dev *ffs_dev;
3390
3391 ENTER();
3392 ffs_dev_lock();
3393
3394 ffs_dev = ffs_data->private_data;
ea365922 3395 if (ffs_dev) {
4b187fce 3396 ffs_dev->mounted = false;
ea365922
AP		 3397
3398 if (ffs_dev->ffs_release_dev_callback)
3399 ffs_dev->ffs_release_dev_callback(ffs_dev);
3400 }
4b187fce
AP		 3401
3402 ffs_dev_unlock();
3403}
3404
3405static int ffs_ready(struct ffs_data *ffs)
3406{
3407 struct ffs_dev *ffs_obj;
3408 int ret = 0;
3409
3410 ENTER();
3411 ffs_dev_lock();
3412
3413 ffs_obj = ffs->private_data;
3414 if (!ffs_obj) {
3415 ret = -EINVAL;
3416 goto done;
3417 }
3418 if (WARN_ON(ffs_obj->desc_ready)) {
3419 ret = -EBUSY;
3420 goto done;
3421 }
3422
3423 ffs_obj->desc_ready = true;
3424 ffs_obj->ffs_data = ffs;
3425
3426 if (ffs_obj->ffs_ready_callback)
3427 ret = ffs_obj->ffs_ready_callback(ffs);
3428
3429done:
3430 ffs_dev_unlock();
3431 return ret;
3432}
3433
3434static void ffs_closed(struct ffs_data *ffs)
3435{
3436 struct ffs_dev *ffs_obj;
3437
3438 ENTER();
3439 ffs_dev_lock();
3440
3441 ffs_obj = ffs->private_data;
3442 if (!ffs_obj)
3443 goto done;
3444
3445 ffs_obj->desc_ready = false;
3446
3447 if (ffs_obj->ffs_closed_callback)
3448 ffs_obj->ffs_closed_callback(ffs);
b658499f
AP		 3449
3450 if (!ffs_obj->opts || ffs_obj->opts->no_configfs
3451 || !ffs_obj->opts->func_inst.group.cg_item.ci_parent)
3452 goto done;
3453
3454 unregister_gadget_item(ffs_obj->opts->
3455 func_inst.group.cg_item.ci_parent->ci_parent);
4b187fce
AP		 3456done:
3457 ffs_dev_unlock();
3458}
3459
ddf8abd2
MN		 3460/* Misc helper functions ****************************************************/
3461
3462static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
3463{
3464 return nonblock
3465 ? likely(mutex_trylock(mutex)) ? 0 : -EAGAIN
3466 : mutex_lock_interruptible(mutex);
3467}
3468
260ef311 3469static char *ffs_prepare_buffer(const char __user *buf, size_t len)
ddf8abd2
MN		 3470{
3471 char *data;
3472
3473 if (unlikely(!len))
3474 return NULL;
3475
3476 data = kmalloc(len, GFP_KERNEL);
3477 if (unlikely(!data))
3478 return ERR_PTR(-ENOMEM);
3479
3480 if (unlikely(__copy_from_user(data, buf, len))) {
3481 kfree(data);
3482 return ERR_PTR(-EFAULT);
3483 }
3484
aa02f172 3485 pr_vdebug("Buffer from user space:\n");
ddf8abd2
MN		 3486 ffs_dump_mem("", data, len);
3487
3488 return data;
3489}
5920cda6 3490
5920cda6
AP		 3491DECLARE_USB_FUNCTION_INIT(ffs, ffs_alloc_inst, ffs_alloc);
3492MODULE_LICENSE("GPL");
3493MODULE_AUTHOR("Michal Nazarewicz");
Linux kernel - Deliverables
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