| 1 | /* |
| 2 | * Event char devices, giving access to raw input device events. |
| 3 | * |
| 4 | * Copyright (c) 1999-2002 Vojtech Pavlik |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify it |
| 7 | * under the terms of the GNU General Public License version 2 as published by |
| 8 | * the Free Software Foundation. |
| 9 | */ |
| 10 | |
| 11 | #define EVDEV_MINOR_BASE 64 |
| 12 | #define EVDEV_MINORS 32 |
| 13 | #define EVDEV_MIN_BUFFER_SIZE 64U |
| 14 | #define EVDEV_BUF_PACKETS 8 |
| 15 | |
| 16 | #include <linux/poll.h> |
| 17 | #include <linux/sched.h> |
| 18 | #include <linux/slab.h> |
| 19 | #include <linux/module.h> |
| 20 | #include <linux/init.h> |
| 21 | #include <linux/input.h> |
| 22 | #include <linux/major.h> |
| 23 | #include <linux/device.h> |
| 24 | #include "input-compat.h" |
| 25 | |
| 26 | struct evdev { |
| 27 | int open; |
| 28 | int minor; |
| 29 | struct input_handle handle; |
| 30 | wait_queue_head_t wait; |
| 31 | struct evdev_client *grab; |
| 32 | struct list_head client_list; |
| 33 | spinlock_t client_lock; /* protects client_list */ |
| 34 | struct mutex mutex; |
| 35 | struct device dev; |
| 36 | bool exist; |
| 37 | }; |
| 38 | |
| 39 | struct evdev_client { |
| 40 | int head; |
| 41 | int tail; |
| 42 | spinlock_t buffer_lock; /* protects access to buffer, head and tail */ |
| 43 | struct fasync_struct *fasync; |
| 44 | struct evdev *evdev; |
| 45 | struct list_head node; |
| 46 | int bufsize; |
| 47 | struct input_event buffer[]; |
| 48 | }; |
| 49 | |
| 50 | static struct evdev *evdev_table[EVDEV_MINORS]; |
| 51 | static DEFINE_MUTEX(evdev_table_mutex); |
| 52 | |
| 53 | static void evdev_pass_event(struct evdev_client *client, |
| 54 | struct input_event *event) |
| 55 | { |
| 56 | /* |
| 57 | * Interrupts are disabled, just acquire the lock. |
| 58 | * Make sure we don't leave with the client buffer |
| 59 | * "empty" by having client->head == client->tail. |
| 60 | */ |
| 61 | spin_lock(&client->buffer_lock); |
| 62 | do { |
| 63 | client->buffer[client->head++] = *event; |
| 64 | client->head &= client->bufsize - 1; |
| 65 | } while (client->head == client->tail); |
| 66 | spin_unlock(&client->buffer_lock); |
| 67 | |
| 68 | if (event->type == EV_SYN) |
| 69 | kill_fasync(&client->fasync, SIGIO, POLL_IN); |
| 70 | } |
| 71 | |
| 72 | /* |
| 73 | * Pass incoming event to all connected clients. |
| 74 | */ |
| 75 | static void evdev_event(struct input_handle *handle, |
| 76 | unsigned int type, unsigned int code, int value) |
| 77 | { |
| 78 | struct evdev *evdev = handle->private; |
| 79 | struct evdev_client *client; |
| 80 | struct input_event event; |
| 81 | |
| 82 | do_gettimeofday(&event.time); |
| 83 | event.type = type; |
| 84 | event.code = code; |
| 85 | event.value = value; |
| 86 | |
| 87 | rcu_read_lock(); |
| 88 | |
| 89 | client = rcu_dereference(evdev->grab); |
| 90 | if (client) |
| 91 | evdev_pass_event(client, &event); |
| 92 | else |
| 93 | list_for_each_entry_rcu(client, &evdev->client_list, node) |
| 94 | evdev_pass_event(client, &event); |
| 95 | |
| 96 | rcu_read_unlock(); |
| 97 | |
| 98 | wake_up_interruptible(&evdev->wait); |
| 99 | } |
| 100 | |
| 101 | static int evdev_fasync(int fd, struct file *file, int on) |
| 102 | { |
| 103 | struct evdev_client *client = file->private_data; |
| 104 | |
| 105 | return fasync_helper(fd, file, on, &client->fasync); |
| 106 | } |
| 107 | |
| 108 | static int evdev_flush(struct file *file, fl_owner_t id) |
| 109 | { |
| 110 | struct evdev_client *client = file->private_data; |
| 111 | struct evdev *evdev = client->evdev; |
| 112 | int retval; |
| 113 | |
| 114 | retval = mutex_lock_interruptible(&evdev->mutex); |
| 115 | if (retval) |
| 116 | return retval; |
| 117 | |
| 118 | if (!evdev->exist) |
| 119 | retval = -ENODEV; |
| 120 | else |
| 121 | retval = input_flush_device(&evdev->handle, file); |
| 122 | |
| 123 | mutex_unlock(&evdev->mutex); |
| 124 | return retval; |
| 125 | } |
| 126 | |
| 127 | static void evdev_free(struct device *dev) |
| 128 | { |
| 129 | struct evdev *evdev = container_of(dev, struct evdev, dev); |
| 130 | |
| 131 | input_put_device(evdev->handle.dev); |
| 132 | kfree(evdev); |
| 133 | } |
| 134 | |
| 135 | /* |
| 136 | * Grabs an event device (along with underlying input device). |
| 137 | * This function is called with evdev->mutex taken. |
| 138 | */ |
| 139 | static int evdev_grab(struct evdev *evdev, struct evdev_client *client) |
| 140 | { |
| 141 | int error; |
| 142 | |
| 143 | if (evdev->grab) |
| 144 | return -EBUSY; |
| 145 | |
| 146 | error = input_grab_device(&evdev->handle); |
| 147 | if (error) |
| 148 | return error; |
| 149 | |
| 150 | rcu_assign_pointer(evdev->grab, client); |
| 151 | synchronize_rcu(); |
| 152 | |
| 153 | return 0; |
| 154 | } |
| 155 | |
| 156 | static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client) |
| 157 | { |
| 158 | if (evdev->grab != client) |
| 159 | return -EINVAL; |
| 160 | |
| 161 | rcu_assign_pointer(evdev->grab, NULL); |
| 162 | synchronize_rcu(); |
| 163 | input_release_device(&evdev->handle); |
| 164 | |
| 165 | return 0; |
| 166 | } |
| 167 | |
| 168 | static void evdev_attach_client(struct evdev *evdev, |
| 169 | struct evdev_client *client) |
| 170 | { |
| 171 | spin_lock(&evdev->client_lock); |
| 172 | list_add_tail_rcu(&client->node, &evdev->client_list); |
| 173 | spin_unlock(&evdev->client_lock); |
| 174 | synchronize_rcu(); |
| 175 | } |
| 176 | |
| 177 | static void evdev_detach_client(struct evdev *evdev, |
| 178 | struct evdev_client *client) |
| 179 | { |
| 180 | spin_lock(&evdev->client_lock); |
| 181 | list_del_rcu(&client->node); |
| 182 | spin_unlock(&evdev->client_lock); |
| 183 | synchronize_rcu(); |
| 184 | } |
| 185 | |
| 186 | static int evdev_open_device(struct evdev *evdev) |
| 187 | { |
| 188 | int retval; |
| 189 | |
| 190 | retval = mutex_lock_interruptible(&evdev->mutex); |
| 191 | if (retval) |
| 192 | return retval; |
| 193 | |
| 194 | if (!evdev->exist) |
| 195 | retval = -ENODEV; |
| 196 | else if (!evdev->open++) { |
| 197 | retval = input_open_device(&evdev->handle); |
| 198 | if (retval) |
| 199 | evdev->open--; |
| 200 | } |
| 201 | |
| 202 | mutex_unlock(&evdev->mutex); |
| 203 | return retval; |
| 204 | } |
| 205 | |
| 206 | static void evdev_close_device(struct evdev *evdev) |
| 207 | { |
| 208 | mutex_lock(&evdev->mutex); |
| 209 | |
| 210 | if (evdev->exist && !--evdev->open) |
| 211 | input_close_device(&evdev->handle); |
| 212 | |
| 213 | mutex_unlock(&evdev->mutex); |
| 214 | } |
| 215 | |
| 216 | /* |
| 217 | * Wake up users waiting for IO so they can disconnect from |
| 218 | * dead device. |
| 219 | */ |
| 220 | static void evdev_hangup(struct evdev *evdev) |
| 221 | { |
| 222 | struct evdev_client *client; |
| 223 | |
| 224 | spin_lock(&evdev->client_lock); |
| 225 | list_for_each_entry(client, &evdev->client_list, node) |
| 226 | kill_fasync(&client->fasync, SIGIO, POLL_HUP); |
| 227 | spin_unlock(&evdev->client_lock); |
| 228 | |
| 229 | wake_up_interruptible(&evdev->wait); |
| 230 | } |
| 231 | |
| 232 | static int evdev_release(struct inode *inode, struct file *file) |
| 233 | { |
| 234 | struct evdev_client *client = file->private_data; |
| 235 | struct evdev *evdev = client->evdev; |
| 236 | |
| 237 | mutex_lock(&evdev->mutex); |
| 238 | if (evdev->grab == client) |
| 239 | evdev_ungrab(evdev, client); |
| 240 | mutex_unlock(&evdev->mutex); |
| 241 | |
| 242 | evdev_detach_client(evdev, client); |
| 243 | kfree(client); |
| 244 | |
| 245 | evdev_close_device(evdev); |
| 246 | put_device(&evdev->dev); |
| 247 | |
| 248 | return 0; |
| 249 | } |
| 250 | |
| 251 | static unsigned int evdev_compute_buffer_size(struct input_dev *dev) |
| 252 | { |
| 253 | unsigned int n_events = |
| 254 | max(dev->hint_events_per_packet * EVDEV_BUF_PACKETS, |
| 255 | EVDEV_MIN_BUFFER_SIZE); |
| 256 | |
| 257 | return roundup_pow_of_two(n_events); |
| 258 | } |
| 259 | |
| 260 | static int evdev_open(struct inode *inode, struct file *file) |
| 261 | { |
| 262 | struct evdev *evdev; |
| 263 | struct evdev_client *client; |
| 264 | int i = iminor(inode) - EVDEV_MINOR_BASE; |
| 265 | unsigned int bufsize; |
| 266 | int error; |
| 267 | |
| 268 | if (i >= EVDEV_MINORS) |
| 269 | return -ENODEV; |
| 270 | |
| 271 | error = mutex_lock_interruptible(&evdev_table_mutex); |
| 272 | if (error) |
| 273 | return error; |
| 274 | evdev = evdev_table[i]; |
| 275 | if (evdev) |
| 276 | get_device(&evdev->dev); |
| 277 | mutex_unlock(&evdev_table_mutex); |
| 278 | |
| 279 | if (!evdev) |
| 280 | return -ENODEV; |
| 281 | |
| 282 | bufsize = evdev_compute_buffer_size(evdev->handle.dev); |
| 283 | |
| 284 | client = kzalloc(sizeof(struct evdev_client) + |
| 285 | bufsize * sizeof(struct input_event), |
| 286 | GFP_KERNEL); |
| 287 | if (!client) { |
| 288 | error = -ENOMEM; |
| 289 | goto err_put_evdev; |
| 290 | } |
| 291 | |
| 292 | client->bufsize = bufsize; |
| 293 | spin_lock_init(&client->buffer_lock); |
| 294 | client->evdev = evdev; |
| 295 | evdev_attach_client(evdev, client); |
| 296 | |
| 297 | error = evdev_open_device(evdev); |
| 298 | if (error) |
| 299 | goto err_free_client; |
| 300 | |
| 301 | file->private_data = client; |
| 302 | nonseekable_open(inode, file); |
| 303 | |
| 304 | return 0; |
| 305 | |
| 306 | err_free_client: |
| 307 | evdev_detach_client(evdev, client); |
| 308 | kfree(client); |
| 309 | err_put_evdev: |
| 310 | put_device(&evdev->dev); |
| 311 | return error; |
| 312 | } |
| 313 | |
| 314 | static ssize_t evdev_write(struct file *file, const char __user *buffer, |
| 315 | size_t count, loff_t *ppos) |
| 316 | { |
| 317 | struct evdev_client *client = file->private_data; |
| 318 | struct evdev *evdev = client->evdev; |
| 319 | struct input_event event; |
| 320 | int retval; |
| 321 | |
| 322 | retval = mutex_lock_interruptible(&evdev->mutex); |
| 323 | if (retval) |
| 324 | return retval; |
| 325 | |
| 326 | if (!evdev->exist) { |
| 327 | retval = -ENODEV; |
| 328 | goto out; |
| 329 | } |
| 330 | |
| 331 | while (retval < count) { |
| 332 | |
| 333 | if (input_event_from_user(buffer + retval, &event)) { |
| 334 | retval = -EFAULT; |
| 335 | goto out; |
| 336 | } |
| 337 | |
| 338 | input_inject_event(&evdev->handle, |
| 339 | event.type, event.code, event.value); |
| 340 | retval += input_event_size(); |
| 341 | } |
| 342 | |
| 343 | out: |
| 344 | mutex_unlock(&evdev->mutex); |
| 345 | return retval; |
| 346 | } |
| 347 | |
| 348 | static int evdev_fetch_next_event(struct evdev_client *client, |
| 349 | struct input_event *event) |
| 350 | { |
| 351 | int have_event; |
| 352 | |
| 353 | spin_lock_irq(&client->buffer_lock); |
| 354 | |
| 355 | have_event = client->head != client->tail; |
| 356 | if (have_event) { |
| 357 | *event = client->buffer[client->tail++]; |
| 358 | client->tail &= client->bufsize - 1; |
| 359 | } |
| 360 | |
| 361 | spin_unlock_irq(&client->buffer_lock); |
| 362 | |
| 363 | return have_event; |
| 364 | } |
| 365 | |
| 366 | static ssize_t evdev_read(struct file *file, char __user *buffer, |
| 367 | size_t count, loff_t *ppos) |
| 368 | { |
| 369 | struct evdev_client *client = file->private_data; |
| 370 | struct evdev *evdev = client->evdev; |
| 371 | struct input_event event; |
| 372 | int retval; |
| 373 | |
| 374 | if (count < input_event_size()) |
| 375 | return -EINVAL; |
| 376 | |
| 377 | if (client->head == client->tail && evdev->exist && |
| 378 | (file->f_flags & O_NONBLOCK)) |
| 379 | return -EAGAIN; |
| 380 | |
| 381 | retval = wait_event_interruptible(evdev->wait, |
| 382 | client->head != client->tail || !evdev->exist); |
| 383 | if (retval) |
| 384 | return retval; |
| 385 | |
| 386 | if (!evdev->exist) |
| 387 | return -ENODEV; |
| 388 | |
| 389 | while (retval + input_event_size() <= count && |
| 390 | evdev_fetch_next_event(client, &event)) { |
| 391 | |
| 392 | if (input_event_to_user(buffer + retval, &event)) |
| 393 | return -EFAULT; |
| 394 | |
| 395 | retval += input_event_size(); |
| 396 | } |
| 397 | |
| 398 | return retval; |
| 399 | } |
| 400 | |
| 401 | /* No kernel lock - fine */ |
| 402 | static unsigned int evdev_poll(struct file *file, poll_table *wait) |
| 403 | { |
| 404 | struct evdev_client *client = file->private_data; |
| 405 | struct evdev *evdev = client->evdev; |
| 406 | unsigned int mask; |
| 407 | |
| 408 | poll_wait(file, &evdev->wait, wait); |
| 409 | |
| 410 | mask = evdev->exist ? POLLOUT | POLLWRNORM : POLLHUP | POLLERR; |
| 411 | if (client->head != client->tail) |
| 412 | mask |= POLLIN | POLLRDNORM; |
| 413 | |
| 414 | return mask; |
| 415 | } |
| 416 | |
| 417 | #ifdef CONFIG_COMPAT |
| 418 | |
| 419 | #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8) |
| 420 | #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1) |
| 421 | |
| 422 | #ifdef __BIG_ENDIAN |
| 423 | static int bits_to_user(unsigned long *bits, unsigned int maxbit, |
| 424 | unsigned int maxlen, void __user *p, int compat) |
| 425 | { |
| 426 | int len, i; |
| 427 | |
| 428 | if (compat) { |
| 429 | len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t); |
| 430 | if (len > maxlen) |
| 431 | len = maxlen; |
| 432 | |
| 433 | for (i = 0; i < len / sizeof(compat_long_t); i++) |
| 434 | if (copy_to_user((compat_long_t __user *) p + i, |
| 435 | (compat_long_t *) bits + |
| 436 | i + 1 - ((i % 2) << 1), |
| 437 | sizeof(compat_long_t))) |
| 438 | return -EFAULT; |
| 439 | } else { |
| 440 | len = BITS_TO_LONGS(maxbit) * sizeof(long); |
| 441 | if (len > maxlen) |
| 442 | len = maxlen; |
| 443 | |
| 444 | if (copy_to_user(p, bits, len)) |
| 445 | return -EFAULT; |
| 446 | } |
| 447 | |
| 448 | return len; |
| 449 | } |
| 450 | #else |
| 451 | static int bits_to_user(unsigned long *bits, unsigned int maxbit, |
| 452 | unsigned int maxlen, void __user *p, int compat) |
| 453 | { |
| 454 | int len = compat ? |
| 455 | BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) : |
| 456 | BITS_TO_LONGS(maxbit) * sizeof(long); |
| 457 | |
| 458 | if (len > maxlen) |
| 459 | len = maxlen; |
| 460 | |
| 461 | return copy_to_user(p, bits, len) ? -EFAULT : len; |
| 462 | } |
| 463 | #endif /* __BIG_ENDIAN */ |
| 464 | |
| 465 | #else |
| 466 | |
| 467 | static int bits_to_user(unsigned long *bits, unsigned int maxbit, |
| 468 | unsigned int maxlen, void __user *p, int compat) |
| 469 | { |
| 470 | int len = BITS_TO_LONGS(maxbit) * sizeof(long); |
| 471 | |
| 472 | if (len > maxlen) |
| 473 | len = maxlen; |
| 474 | |
| 475 | return copy_to_user(p, bits, len) ? -EFAULT : len; |
| 476 | } |
| 477 | |
| 478 | #endif /* CONFIG_COMPAT */ |
| 479 | |
| 480 | static int str_to_user(const char *str, unsigned int maxlen, void __user *p) |
| 481 | { |
| 482 | int len; |
| 483 | |
| 484 | if (!str) |
| 485 | return -ENOENT; |
| 486 | |
| 487 | len = strlen(str) + 1; |
| 488 | if (len > maxlen) |
| 489 | len = maxlen; |
| 490 | |
| 491 | return copy_to_user(p, str, len) ? -EFAULT : len; |
| 492 | } |
| 493 | |
| 494 | #define OLD_KEY_MAX 0x1ff |
| 495 | static int handle_eviocgbit(struct input_dev *dev, unsigned int cmd, void __user *p, int compat_mode) |
| 496 | { |
| 497 | static unsigned long keymax_warn_time; |
| 498 | unsigned long *bits; |
| 499 | int len; |
| 500 | |
| 501 | switch (_IOC_NR(cmd) & EV_MAX) { |
| 502 | |
| 503 | case 0: bits = dev->evbit; len = EV_MAX; break; |
| 504 | case EV_KEY: bits = dev->keybit; len = KEY_MAX; break; |
| 505 | case EV_REL: bits = dev->relbit; len = REL_MAX; break; |
| 506 | case EV_ABS: bits = dev->absbit; len = ABS_MAX; break; |
| 507 | case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break; |
| 508 | case EV_LED: bits = dev->ledbit; len = LED_MAX; break; |
| 509 | case EV_SND: bits = dev->sndbit; len = SND_MAX; break; |
| 510 | case EV_FF: bits = dev->ffbit; len = FF_MAX; break; |
| 511 | case EV_SW: bits = dev->swbit; len = SW_MAX; break; |
| 512 | default: return -EINVAL; |
| 513 | } |
| 514 | |
| 515 | /* |
| 516 | * Work around bugs in userspace programs that like to do |
| 517 | * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len' |
| 518 | * should be in bytes, not in bits. |
| 519 | */ |
| 520 | if ((_IOC_NR(cmd) & EV_MAX) == EV_KEY && _IOC_SIZE(cmd) == OLD_KEY_MAX) { |
| 521 | len = OLD_KEY_MAX; |
| 522 | if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000)) |
| 523 | printk(KERN_WARNING |
| 524 | "evdev.c(EVIOCGBIT): Suspicious buffer size %u, " |
| 525 | "limiting output to %zu bytes. See " |
| 526 | "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n", |
| 527 | OLD_KEY_MAX, |
| 528 | BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long)); |
| 529 | } |
| 530 | |
| 531 | return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode); |
| 532 | } |
| 533 | #undef OLD_KEY_MAX |
| 534 | |
| 535 | static long evdev_do_ioctl(struct file *file, unsigned int cmd, |
| 536 | void __user *p, int compat_mode) |
| 537 | { |
| 538 | struct evdev_client *client = file->private_data; |
| 539 | struct evdev *evdev = client->evdev; |
| 540 | struct input_dev *dev = evdev->handle.dev; |
| 541 | struct input_absinfo abs; |
| 542 | struct ff_effect effect; |
| 543 | int __user *ip = (int __user *)p; |
| 544 | unsigned int i, t, u, v; |
| 545 | int error; |
| 546 | |
| 547 | switch (cmd) { |
| 548 | |
| 549 | case EVIOCGVERSION: |
| 550 | return put_user(EV_VERSION, ip); |
| 551 | |
| 552 | case EVIOCGID: |
| 553 | if (copy_to_user(p, &dev->id, sizeof(struct input_id))) |
| 554 | return -EFAULT; |
| 555 | return 0; |
| 556 | |
| 557 | case EVIOCGREP: |
| 558 | if (!test_bit(EV_REP, dev->evbit)) |
| 559 | return -ENOSYS; |
| 560 | if (put_user(dev->rep[REP_DELAY], ip)) |
| 561 | return -EFAULT; |
| 562 | if (put_user(dev->rep[REP_PERIOD], ip + 1)) |
| 563 | return -EFAULT; |
| 564 | return 0; |
| 565 | |
| 566 | case EVIOCSREP: |
| 567 | if (!test_bit(EV_REP, dev->evbit)) |
| 568 | return -ENOSYS; |
| 569 | if (get_user(u, ip)) |
| 570 | return -EFAULT; |
| 571 | if (get_user(v, ip + 1)) |
| 572 | return -EFAULT; |
| 573 | |
| 574 | input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u); |
| 575 | input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v); |
| 576 | |
| 577 | return 0; |
| 578 | |
| 579 | case EVIOCGKEYCODE: |
| 580 | if (get_user(t, ip)) |
| 581 | return -EFAULT; |
| 582 | |
| 583 | error = input_get_keycode(dev, t, &v); |
| 584 | if (error) |
| 585 | return error; |
| 586 | |
| 587 | if (put_user(v, ip + 1)) |
| 588 | return -EFAULT; |
| 589 | |
| 590 | return 0; |
| 591 | |
| 592 | case EVIOCSKEYCODE: |
| 593 | if (get_user(t, ip) || get_user(v, ip + 1)) |
| 594 | return -EFAULT; |
| 595 | |
| 596 | return input_set_keycode(dev, t, v); |
| 597 | |
| 598 | case EVIOCRMFF: |
| 599 | return input_ff_erase(dev, (int)(unsigned long) p, file); |
| 600 | |
| 601 | case EVIOCGEFFECTS: |
| 602 | i = test_bit(EV_FF, dev->evbit) ? |
| 603 | dev->ff->max_effects : 0; |
| 604 | if (put_user(i, ip)) |
| 605 | return -EFAULT; |
| 606 | return 0; |
| 607 | |
| 608 | case EVIOCGRAB: |
| 609 | if (p) |
| 610 | return evdev_grab(evdev, client); |
| 611 | else |
| 612 | return evdev_ungrab(evdev, client); |
| 613 | |
| 614 | default: |
| 615 | |
| 616 | if (_IOC_TYPE(cmd) != 'E') |
| 617 | return -EINVAL; |
| 618 | |
| 619 | if (_IOC_DIR(cmd) == _IOC_READ) { |
| 620 | |
| 621 | if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0))) |
| 622 | return handle_eviocgbit(dev, cmd, p, compat_mode); |
| 623 | |
| 624 | if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0))) |
| 625 | return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd), |
| 626 | p, compat_mode); |
| 627 | |
| 628 | if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0))) |
| 629 | return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd), |
| 630 | p, compat_mode); |
| 631 | |
| 632 | if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0))) |
| 633 | return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd), |
| 634 | p, compat_mode); |
| 635 | |
| 636 | if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0))) |
| 637 | return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd), |
| 638 | p, compat_mode); |
| 639 | |
| 640 | if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) |
| 641 | return str_to_user(dev->name, _IOC_SIZE(cmd), p); |
| 642 | |
| 643 | if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) |
| 644 | return str_to_user(dev->phys, _IOC_SIZE(cmd), p); |
| 645 | |
| 646 | if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) |
| 647 | return str_to_user(dev->uniq, _IOC_SIZE(cmd), p); |
| 648 | |
| 649 | if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) { |
| 650 | |
| 651 | t = _IOC_NR(cmd) & ABS_MAX; |
| 652 | |
| 653 | abs.value = dev->abs[t]; |
| 654 | abs.minimum = dev->absmin[t]; |
| 655 | abs.maximum = dev->absmax[t]; |
| 656 | abs.fuzz = dev->absfuzz[t]; |
| 657 | abs.flat = dev->absflat[t]; |
| 658 | abs.resolution = dev->absres[t]; |
| 659 | |
| 660 | if (copy_to_user(p, &abs, min_t(size_t, |
| 661 | _IOC_SIZE(cmd), |
| 662 | sizeof(struct input_absinfo)))) |
| 663 | return -EFAULT; |
| 664 | |
| 665 | return 0; |
| 666 | } |
| 667 | |
| 668 | } |
| 669 | |
| 670 | if (_IOC_DIR(cmd) == _IOC_WRITE) { |
| 671 | |
| 672 | if (_IOC_NR(cmd) == _IOC_NR(EVIOCSFF)) { |
| 673 | |
| 674 | if (input_ff_effect_from_user(p, _IOC_SIZE(cmd), &effect)) |
| 675 | return -EFAULT; |
| 676 | |
| 677 | error = input_ff_upload(dev, &effect, file); |
| 678 | |
| 679 | if (put_user(effect.id, &(((struct ff_effect __user *)p)->id))) |
| 680 | return -EFAULT; |
| 681 | |
| 682 | return error; |
| 683 | } |
| 684 | |
| 685 | if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) { |
| 686 | |
| 687 | t = _IOC_NR(cmd) & ABS_MAX; |
| 688 | |
| 689 | if (copy_from_user(&abs, p, min_t(size_t, |
| 690 | _IOC_SIZE(cmd), |
| 691 | sizeof(struct input_absinfo)))) |
| 692 | return -EFAULT; |
| 693 | |
| 694 | /* We can't change number of reserved MT slots */ |
| 695 | if (t == ABS_MT_SLOT) |
| 696 | return -EINVAL; |
| 697 | |
| 698 | /* |
| 699 | * Take event lock to ensure that we are not |
| 700 | * changing device parameters in the middle |
| 701 | * of event. |
| 702 | */ |
| 703 | spin_lock_irq(&dev->event_lock); |
| 704 | |
| 705 | dev->abs[t] = abs.value; |
| 706 | dev->absmin[t] = abs.minimum; |
| 707 | dev->absmax[t] = abs.maximum; |
| 708 | dev->absfuzz[t] = abs.fuzz; |
| 709 | dev->absflat[t] = abs.flat; |
| 710 | dev->absres[t] = _IOC_SIZE(cmd) < sizeof(struct input_absinfo) ? |
| 711 | 0 : abs.resolution; |
| 712 | |
| 713 | spin_unlock_irq(&dev->event_lock); |
| 714 | |
| 715 | return 0; |
| 716 | } |
| 717 | } |
| 718 | } |
| 719 | return -EINVAL; |
| 720 | } |
| 721 | |
| 722 | static long evdev_ioctl_handler(struct file *file, unsigned int cmd, |
| 723 | void __user *p, int compat_mode) |
| 724 | { |
| 725 | struct evdev_client *client = file->private_data; |
| 726 | struct evdev *evdev = client->evdev; |
| 727 | int retval; |
| 728 | |
| 729 | retval = mutex_lock_interruptible(&evdev->mutex); |
| 730 | if (retval) |
| 731 | return retval; |
| 732 | |
| 733 | if (!evdev->exist) { |
| 734 | retval = -ENODEV; |
| 735 | goto out; |
| 736 | } |
| 737 | |
| 738 | retval = evdev_do_ioctl(file, cmd, p, compat_mode); |
| 739 | |
| 740 | out: |
| 741 | mutex_unlock(&evdev->mutex); |
| 742 | return retval; |
| 743 | } |
| 744 | |
| 745 | static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
| 746 | { |
| 747 | return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0); |
| 748 | } |
| 749 | |
| 750 | #ifdef CONFIG_COMPAT |
| 751 | static long evdev_ioctl_compat(struct file *file, |
| 752 | unsigned int cmd, unsigned long arg) |
| 753 | { |
| 754 | return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1); |
| 755 | } |
| 756 | #endif |
| 757 | |
| 758 | static const struct file_operations evdev_fops = { |
| 759 | .owner = THIS_MODULE, |
| 760 | .read = evdev_read, |
| 761 | .write = evdev_write, |
| 762 | .poll = evdev_poll, |
| 763 | .open = evdev_open, |
| 764 | .release = evdev_release, |
| 765 | .unlocked_ioctl = evdev_ioctl, |
| 766 | #ifdef CONFIG_COMPAT |
| 767 | .compat_ioctl = evdev_ioctl_compat, |
| 768 | #endif |
| 769 | .fasync = evdev_fasync, |
| 770 | .flush = evdev_flush |
| 771 | }; |
| 772 | |
| 773 | static int evdev_install_chrdev(struct evdev *evdev) |
| 774 | { |
| 775 | /* |
| 776 | * No need to do any locking here as calls to connect and |
| 777 | * disconnect are serialized by the input core |
| 778 | */ |
| 779 | evdev_table[evdev->minor] = evdev; |
| 780 | return 0; |
| 781 | } |
| 782 | |
| 783 | static void evdev_remove_chrdev(struct evdev *evdev) |
| 784 | { |
| 785 | /* |
| 786 | * Lock evdev table to prevent race with evdev_open() |
| 787 | */ |
| 788 | mutex_lock(&evdev_table_mutex); |
| 789 | evdev_table[evdev->minor] = NULL; |
| 790 | mutex_unlock(&evdev_table_mutex); |
| 791 | } |
| 792 | |
| 793 | /* |
| 794 | * Mark device non-existent. This disables writes, ioctls and |
| 795 | * prevents new users from opening the device. Already posted |
| 796 | * blocking reads will stay, however new ones will fail. |
| 797 | */ |
| 798 | static void evdev_mark_dead(struct evdev *evdev) |
| 799 | { |
| 800 | mutex_lock(&evdev->mutex); |
| 801 | evdev->exist = false; |
| 802 | mutex_unlock(&evdev->mutex); |
| 803 | } |
| 804 | |
| 805 | static void evdev_cleanup(struct evdev *evdev) |
| 806 | { |
| 807 | struct input_handle *handle = &evdev->handle; |
| 808 | |
| 809 | evdev_mark_dead(evdev); |
| 810 | evdev_hangup(evdev); |
| 811 | evdev_remove_chrdev(evdev); |
| 812 | |
| 813 | /* evdev is marked dead so no one else accesses evdev->open */ |
| 814 | if (evdev->open) { |
| 815 | input_flush_device(handle, NULL); |
| 816 | input_close_device(handle); |
| 817 | } |
| 818 | } |
| 819 | |
| 820 | /* |
| 821 | * Create new evdev device. Note that input core serializes calls |
| 822 | * to connect and disconnect so we don't need to lock evdev_table here. |
| 823 | */ |
| 824 | static int evdev_connect(struct input_handler *handler, struct input_dev *dev, |
| 825 | const struct input_device_id *id) |
| 826 | { |
| 827 | struct evdev *evdev; |
| 828 | int minor; |
| 829 | int error; |
| 830 | |
| 831 | for (minor = 0; minor < EVDEV_MINORS; minor++) |
| 832 | if (!evdev_table[minor]) |
| 833 | break; |
| 834 | |
| 835 | if (minor == EVDEV_MINORS) { |
| 836 | printk(KERN_ERR "evdev: no more free evdev devices\n"); |
| 837 | return -ENFILE; |
| 838 | } |
| 839 | |
| 840 | evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL); |
| 841 | if (!evdev) |
| 842 | return -ENOMEM; |
| 843 | |
| 844 | INIT_LIST_HEAD(&evdev->client_list); |
| 845 | spin_lock_init(&evdev->client_lock); |
| 846 | mutex_init(&evdev->mutex); |
| 847 | init_waitqueue_head(&evdev->wait); |
| 848 | |
| 849 | dev_set_name(&evdev->dev, "event%d", minor); |
| 850 | evdev->exist = true; |
| 851 | evdev->minor = minor; |
| 852 | |
| 853 | evdev->handle.dev = input_get_device(dev); |
| 854 | evdev->handle.name = dev_name(&evdev->dev); |
| 855 | evdev->handle.handler = handler; |
| 856 | evdev->handle.private = evdev; |
| 857 | |
| 858 | evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor); |
| 859 | evdev->dev.class = &input_class; |
| 860 | evdev->dev.parent = &dev->dev; |
| 861 | evdev->dev.release = evdev_free; |
| 862 | device_initialize(&evdev->dev); |
| 863 | |
| 864 | error = input_register_handle(&evdev->handle); |
| 865 | if (error) |
| 866 | goto err_free_evdev; |
| 867 | |
| 868 | error = evdev_install_chrdev(evdev); |
| 869 | if (error) |
| 870 | goto err_unregister_handle; |
| 871 | |
| 872 | error = device_add(&evdev->dev); |
| 873 | if (error) |
| 874 | goto err_cleanup_evdev; |
| 875 | |
| 876 | return 0; |
| 877 | |
| 878 | err_cleanup_evdev: |
| 879 | evdev_cleanup(evdev); |
| 880 | err_unregister_handle: |
| 881 | input_unregister_handle(&evdev->handle); |
| 882 | err_free_evdev: |
| 883 | put_device(&evdev->dev); |
| 884 | return error; |
| 885 | } |
| 886 | |
| 887 | static void evdev_disconnect(struct input_handle *handle) |
| 888 | { |
| 889 | struct evdev *evdev = handle->private; |
| 890 | |
| 891 | device_del(&evdev->dev); |
| 892 | evdev_cleanup(evdev); |
| 893 | input_unregister_handle(handle); |
| 894 | put_device(&evdev->dev); |
| 895 | } |
| 896 | |
| 897 | static const struct input_device_id evdev_ids[] = { |
| 898 | { .driver_info = 1 }, /* Matches all devices */ |
| 899 | { }, /* Terminating zero entry */ |
| 900 | }; |
| 901 | |
| 902 | MODULE_DEVICE_TABLE(input, evdev_ids); |
| 903 | |
| 904 | static struct input_handler evdev_handler = { |
| 905 | .event = evdev_event, |
| 906 | .connect = evdev_connect, |
| 907 | .disconnect = evdev_disconnect, |
| 908 | .fops = &evdev_fops, |
| 909 | .minor = EVDEV_MINOR_BASE, |
| 910 | .name = "evdev", |
| 911 | .id_table = evdev_ids, |
| 912 | }; |
| 913 | |
| 914 | static int __init evdev_init(void) |
| 915 | { |
| 916 | return input_register_handler(&evdev_handler); |
| 917 | } |
| 918 | |
| 919 | static void __exit evdev_exit(void) |
| 920 | { |
| 921 | input_unregister_handler(&evdev_handler); |
| 922 | } |
| 923 | |
| 924 | module_init(evdev_init); |
| 925 | module_exit(evdev_exit); |
| 926 | |
| 927 | MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); |
| 928 | MODULE_DESCRIPTION("Input driver event char devices"); |
| 929 | MODULE_LICENSE("GPL"); |