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