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v4.6
   1/*
   2 *  User level driver support for input subsystem
   3 *
   4 * Heavily based on evdev.c by Vojtech Pavlik
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program; if not, write to the Free Software
  18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19 *
  20 * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
  21 *
  22 * Changes/Revisions:
  23 *	0.4	01/09/2014 (Benjamin Tissoires <benjamin.tissoires@redhat.com>)
  24 *		- add UI_GET_SYSNAME ioctl
  25 *	0.3	09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>)
  26 *		- updated ff support for the changes in kernel interface
  27 *		- added MODULE_VERSION
  28 *	0.2	16/10/2004 (Micah Dowty <micah@navi.cx>)
  29 *		- added force feedback support
  30 *              - added UI_SET_PHYS
  31 *	0.1	20/06/2002
  32 *		- first public version
  33 */
  34#include <linux/poll.h>
  35#include <linux/sched.h>
  36#include <linux/slab.h>
  37#include <linux/module.h>
  38#include <linux/init.h>
  39#include <linux/fs.h>
  40#include <linux/miscdevice.h>
  41#include <linux/uinput.h>
  42#include <linux/input/mt.h>
  43#include "../input-compat.h"
  44
  45static int uinput_dev_event(struct input_dev *dev,
  46			    unsigned int type, unsigned int code, int value)
  47{
  48	struct uinput_device	*udev = input_get_drvdata(dev);
  49
  50	udev->buff[udev->head].type = type;
  51	udev->buff[udev->head].code = code;
  52	udev->buff[udev->head].value = value;
  53	do_gettimeofday(&udev->buff[udev->head].time);
  54	udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
  55
  56	wake_up_interruptible(&udev->waitq);
  57
  58	return 0;
  59}
  60
  61/* Atomically allocate an ID for the given request. Returns 0 on success. */
  62static bool uinput_request_alloc_id(struct uinput_device *udev,
  63				    struct uinput_request *request)
  64{
  65	unsigned int id;
  66	bool reserved = false;
  67
  68	spin_lock(&udev->requests_lock);
  69
  70	for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
  71		if (!udev->requests[id]) {
  72			request->id = id;
  73			udev->requests[id] = request;
  74			reserved = true;
  75			break;
  76		}
  77	}
  78
  79	spin_unlock(&udev->requests_lock);
  80	return reserved;
  81}
  82
  83static struct uinput_request *uinput_request_find(struct uinput_device *udev,
  84						  unsigned int id)
  85{
  86	/* Find an input request, by ID. Returns NULL if the ID isn't valid. */
  87	if (id >= UINPUT_NUM_REQUESTS)
  88		return NULL;
  89
  90	return udev->requests[id];
  91}
  92
  93static int uinput_request_reserve_slot(struct uinput_device *udev,
  94				       struct uinput_request *request)
  95{
  96	/* Allocate slot. If none are available right away, wait. */
  97	return wait_event_interruptible(udev->requests_waitq,
  98					uinput_request_alloc_id(udev, request));
  99}
 100
 101static void uinput_request_done(struct uinput_device *udev,
 102				struct uinput_request *request)
 103{
 104	/* Mark slot as available */
 105	udev->requests[request->id] = NULL;
 106	wake_up(&udev->requests_waitq);
 107
 108	complete(&request->done);
 109}
 110
 111static int uinput_request_send(struct uinput_device *udev,
 112			       struct uinput_request *request)
 113{
 114	int retval;
 115
 116	retval = mutex_lock_interruptible(&udev->mutex);
 117	if (retval)
 118		return retval;
 119
 120	if (udev->state != UIST_CREATED) {
 121		retval = -ENODEV;
 122		goto out;
 123	}
 124
 125	init_completion(&request->done);
 126
 127	/*
 128	 * Tell our userspace application about this new request
 129	 * by queueing an input event.
 130	 */
 131	uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
 132
 133 out:
 134	mutex_unlock(&udev->mutex);
 135	return retval;
 136}
 137
 138static int uinput_request_submit(struct uinput_device *udev,
 139				 struct uinput_request *request)
 140{
 141	int error;
 142
 143	error = uinput_request_reserve_slot(udev, request);
 144	if (error)
 145		return error;
 146
 147	error = uinput_request_send(udev, request);
 148	if (error) {
 149		uinput_request_done(udev, request);
 150		return error;
 151	}
 152
 153	wait_for_completion(&request->done);
 154	return request->retval;
 155}
 156
 157/*
 158 * Fail all outstanding requests so handlers don't wait for the userspace
 159 * to finish processing them.
 160 */
 161static void uinput_flush_requests(struct uinput_device *udev)
 162{
 163	struct uinput_request *request;
 164	int i;
 165
 166	spin_lock(&udev->requests_lock);
 167
 168	for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
 169		request = udev->requests[i];
 170		if (request) {
 171			request->retval = -ENODEV;
 172			uinput_request_done(udev, request);
 173		}
 174	}
 175
 176	spin_unlock(&udev->requests_lock);
 177}
 178
 179static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
 180{
 181	uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
 182}
 183
 184static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
 185{
 186	uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
 187}
 188
 189static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
 190{
 191	return uinput_dev_event(dev, EV_FF, effect_id, value);
 192}
 193
 194static int uinput_dev_upload_effect(struct input_dev *dev,
 195				    struct ff_effect *effect,
 196				    struct ff_effect *old)
 197{
 198	struct uinput_device *udev = input_get_drvdata(dev);
 199	struct uinput_request request;
 200
 201	/*
 202	 * uinput driver does not currently support periodic effects with
 203	 * custom waveform since it does not have a way to pass buffer of
 204	 * samples (custom_data) to userspace. If ever there is a device
 205	 * supporting custom waveforms we would need to define an additional
 206	 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
 207	 */
 208	if (effect->type == FF_PERIODIC &&
 209			effect->u.periodic.waveform == FF_CUSTOM)
 210		return -EINVAL;
 211
 212	request.code = UI_FF_UPLOAD;
 213	request.u.upload.effect = effect;
 214	request.u.upload.old = old;
 215
 216	return uinput_request_submit(udev, &request);
 217}
 218
 219static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
 220{
 221	struct uinput_device *udev = input_get_drvdata(dev);
 222	struct uinput_request request;
 223
 224	if (!test_bit(EV_FF, dev->evbit))
 225		return -ENOSYS;
 226
 227	request.code = UI_FF_ERASE;
 228	request.u.effect_id = effect_id;
 229
 230	return uinput_request_submit(udev, &request);
 231}
 232
 233static void uinput_destroy_device(struct uinput_device *udev)
 234{
 235	const char *name, *phys;
 236	struct input_dev *dev = udev->dev;
 237	enum uinput_state old_state = udev->state;
 238
 239	udev->state = UIST_NEW_DEVICE;
 240
 241	if (dev) {
 242		name = dev->name;
 243		phys = dev->phys;
 244		if (old_state == UIST_CREATED) {
 245			uinput_flush_requests(udev);
 246			input_unregister_device(dev);
 247		} else {
 248			input_free_device(dev);
 249		}
 250		kfree(name);
 251		kfree(phys);
 252		udev->dev = NULL;
 253	}
 254}
 255
 256static int uinput_create_device(struct uinput_device *udev)
 257{
 258	struct input_dev *dev = udev->dev;
 259	int error, nslot;
 260
 261	if (udev->state != UIST_SETUP_COMPLETE) {
 262		printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
 263		return -EINVAL;
 264	}
 265
 266	if (test_bit(ABS_MT_SLOT, dev->absbit)) {
 267		nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
 268		error = input_mt_init_slots(dev, nslot, 0);
 269		if (error)
 270			goto fail1;
 271	} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
 272		input_set_events_per_packet(dev, 60);
 
 
 
 
 
 
 
 
 273	}
 274
 275	if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) {
 276		printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n",
 277			UINPUT_NAME);
 278		error = -EINVAL;
 279		goto fail1;
 280	}
 281
 282	if (udev->ff_effects_max) {
 283		error = input_ff_create(dev, udev->ff_effects_max);
 284		if (error)
 285			goto fail1;
 286
 287		dev->ff->upload = uinput_dev_upload_effect;
 288		dev->ff->erase = uinput_dev_erase_effect;
 289		dev->ff->playback = uinput_dev_playback;
 290		dev->ff->set_gain = uinput_dev_set_gain;
 291		dev->ff->set_autocenter = uinput_dev_set_autocenter;
 292	}
 293
 294	error = input_register_device(udev->dev);
 295	if (error)
 296		goto fail2;
 297
 298	udev->state = UIST_CREATED;
 299
 300	return 0;
 301
 302 fail2:	input_ff_destroy(dev);
 303 fail1: uinput_destroy_device(udev);
 304	return error;
 305}
 306
 307static int uinput_open(struct inode *inode, struct file *file)
 308{
 309	struct uinput_device *newdev;
 310
 311	newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
 312	if (!newdev)
 313		return -ENOMEM;
 314
 315	mutex_init(&newdev->mutex);
 316	spin_lock_init(&newdev->requests_lock);
 317	init_waitqueue_head(&newdev->requests_waitq);
 318	init_waitqueue_head(&newdev->waitq);
 319	newdev->state = UIST_NEW_DEVICE;
 320
 321	file->private_data = newdev;
 322	nonseekable_open(inode, file);
 323
 324	return 0;
 325}
 326
 327static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code,
 328				   const struct input_absinfo *abs)
 329{
 330	int min, max;
 331
 332	min = abs->minimum;
 333	max = abs->maximum;
 334
 335	if ((min != 0 || max != 0) && max <= min) {
 336		printk(KERN_DEBUG
 337		       "%s: invalid abs[%02x] min:%d max:%d\n",
 338		       UINPUT_NAME, code, min, max);
 339		return -EINVAL;
 340	}
 341
 342	if (abs->flat > max - min) {
 343		printk(KERN_DEBUG
 344		       "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n",
 345		       UINPUT_NAME, code, abs->flat, min, max);
 346		return -EINVAL;
 347	}
 348
 349	return 0;
 350}
 351
 352static int uinput_validate_absbits(struct input_dev *dev)
 353{
 354	unsigned int cnt;
 355	int error;
 356
 357	if (!test_bit(EV_ABS, dev->evbit))
 358		return 0;
 359
 360	/*
 361	 * Check if absmin/absmax/absfuzz/absflat are sane.
 362	 */
 363
 364	for_each_set_bit(cnt, dev->absbit, ABS_CNT) {
 365		if (!dev->absinfo)
 366			return -EINVAL;
 367
 368		error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]);
 369		if (error)
 370			return error;
 371	}
 372
 373	return 0;
 374}
 375
 376static int uinput_allocate_device(struct uinput_device *udev)
 377{
 378	udev->dev = input_allocate_device();
 379	if (!udev->dev)
 380		return -ENOMEM;
 381
 382	udev->dev->event = uinput_dev_event;
 383	input_set_drvdata(udev->dev, udev);
 384
 385	return 0;
 386}
 387
 388static int uinput_dev_setup(struct uinput_device *udev,
 389			    struct uinput_setup __user *arg)
 390{
 391	struct uinput_setup setup;
 392	struct input_dev *dev;
 393
 394	if (udev->state == UIST_CREATED)
 395		return -EINVAL;
 396
 397	if (copy_from_user(&setup, arg, sizeof(setup)))
 398		return -EFAULT;
 399
 400	if (!setup.name[0])
 401		return -EINVAL;
 402
 403	dev = udev->dev;
 404	dev->id = setup.id;
 405	udev->ff_effects_max = setup.ff_effects_max;
 406
 407	kfree(dev->name);
 408	dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL);
 409	if (!dev->name)
 410		return -ENOMEM;
 411
 412	udev->state = UIST_SETUP_COMPLETE;
 413	return 0;
 414}
 415
 416static int uinput_abs_setup(struct uinput_device *udev,
 417			    struct uinput_setup __user *arg, size_t size)
 418{
 419	struct uinput_abs_setup setup = {};
 420	struct input_dev *dev;
 421	int error;
 422
 423	if (size > sizeof(setup))
 424		return -E2BIG;
 425
 426	if (udev->state == UIST_CREATED)
 427		return -EINVAL;
 428
 429	if (copy_from_user(&setup, arg, size))
 430		return -EFAULT;
 431
 432	if (setup.code > ABS_MAX)
 433		return -ERANGE;
 434
 435	dev = udev->dev;
 436
 437	error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo);
 438	if (error)
 439		return error;
 440
 441	input_alloc_absinfo(dev);
 442	if (!dev->absinfo)
 443		return -ENOMEM;
 444
 445	set_bit(setup.code, dev->absbit);
 446	dev->absinfo[setup.code] = setup.absinfo;
 447	return 0;
 448}
 449
 450/* legacy setup via write() */
 451static int uinput_setup_device_legacy(struct uinput_device *udev,
 452				      const char __user *buffer, size_t count)
 453{
 454	struct uinput_user_dev	*user_dev;
 455	struct input_dev	*dev;
 456	int			i;
 457	int			retval;
 458
 459	if (count != sizeof(struct uinput_user_dev))
 460		return -EINVAL;
 461
 462	if (!udev->dev) {
 463		retval = uinput_allocate_device(udev);
 464		if (retval)
 465			return retval;
 466	}
 467
 468	dev = udev->dev;
 469
 470	user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
 471	if (IS_ERR(user_dev))
 472		return PTR_ERR(user_dev);
 473
 474	udev->ff_effects_max = user_dev->ff_effects_max;
 475
 476	/* Ensure name is filled in */
 477	if (!user_dev->name[0]) {
 478		retval = -EINVAL;
 479		goto exit;
 480	}
 481
 482	kfree(dev->name);
 483	dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
 484			     GFP_KERNEL);
 485	if (!dev->name) {
 486		retval = -ENOMEM;
 487		goto exit;
 488	}
 489
 490	dev->id.bustype	= user_dev->id.bustype;
 491	dev->id.vendor	= user_dev->id.vendor;
 492	dev->id.product	= user_dev->id.product;
 493	dev->id.version	= user_dev->id.version;
 494
 495	for (i = 0; i < ABS_CNT; i++) {
 496		input_abs_set_max(dev, i, user_dev->absmax[i]);
 497		input_abs_set_min(dev, i, user_dev->absmin[i]);
 498		input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
 499		input_abs_set_flat(dev, i, user_dev->absflat[i]);
 500	}
 501
 502	retval = uinput_validate_absbits(dev);
 503	if (retval < 0)
 504		goto exit;
 505
 506	udev->state = UIST_SETUP_COMPLETE;
 507	retval = count;
 508
 509 exit:
 510	kfree(user_dev);
 511	return retval;
 512}
 513
 514static ssize_t uinput_inject_events(struct uinput_device *udev,
 515				    const char __user *buffer, size_t count)
 516{
 517	struct input_event ev;
 518	size_t bytes = 0;
 519
 520	if (count != 0 && count < input_event_size())
 521		return -EINVAL;
 522
 523	while (bytes + input_event_size() <= count) {
 524		/*
 525		 * Note that even if some events were fetched successfully
 526		 * we are still going to return EFAULT instead of partial
 527		 * count to let userspace know that it got it's buffers
 528		 * all wrong.
 529		 */
 530		if (input_event_from_user(buffer + bytes, &ev))
 531			return -EFAULT;
 532
 533		input_event(udev->dev, ev.type, ev.code, ev.value);
 534		bytes += input_event_size();
 535	}
 536
 537	return bytes;
 538}
 539
 540static ssize_t uinput_write(struct file *file, const char __user *buffer,
 541			    size_t count, loff_t *ppos)
 542{
 543	struct uinput_device *udev = file->private_data;
 544	int retval;
 545
 546	if (count == 0)
 547		return 0;
 548
 549	retval = mutex_lock_interruptible(&udev->mutex);
 550	if (retval)
 551		return retval;
 552
 553	retval = udev->state == UIST_CREATED ?
 554			uinput_inject_events(udev, buffer, count) :
 555			uinput_setup_device_legacy(udev, buffer, count);
 556
 557	mutex_unlock(&udev->mutex);
 558
 559	return retval;
 560}
 561
 562static bool uinput_fetch_next_event(struct uinput_device *udev,
 563				    struct input_event *event)
 564{
 565	bool have_event;
 566
 567	spin_lock_irq(&udev->dev->event_lock);
 568
 569	have_event = udev->head != udev->tail;
 570	if (have_event) {
 571		*event = udev->buff[udev->tail];
 572		udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
 573	}
 574
 575	spin_unlock_irq(&udev->dev->event_lock);
 576
 577	return have_event;
 578}
 579
 580static ssize_t uinput_events_to_user(struct uinput_device *udev,
 581				     char __user *buffer, size_t count)
 582{
 583	struct input_event event;
 584	size_t read = 0;
 585
 586	while (read + input_event_size() <= count &&
 587	       uinput_fetch_next_event(udev, &event)) {
 588
 589		if (input_event_to_user(buffer + read, &event))
 590			return -EFAULT;
 591
 592		read += input_event_size();
 593	}
 594
 595	return read;
 596}
 597
 598static ssize_t uinput_read(struct file *file, char __user *buffer,
 599			   size_t count, loff_t *ppos)
 600{
 601	struct uinput_device *udev = file->private_data;
 602	ssize_t retval;
 603
 604	if (count != 0 && count < input_event_size())
 605		return -EINVAL;
 606
 607	do {
 608		retval = mutex_lock_interruptible(&udev->mutex);
 609		if (retval)
 610			return retval;
 611
 612		if (udev->state != UIST_CREATED)
 613			retval = -ENODEV;
 614		else if (udev->head == udev->tail &&
 615			 (file->f_flags & O_NONBLOCK))
 616			retval = -EAGAIN;
 617		else
 618			retval = uinput_events_to_user(udev, buffer, count);
 619
 620		mutex_unlock(&udev->mutex);
 621
 622		if (retval || count == 0)
 623			break;
 624
 625		if (!(file->f_flags & O_NONBLOCK))
 626			retval = wait_event_interruptible(udev->waitq,
 627						  udev->head != udev->tail ||
 628						  udev->state != UIST_CREATED);
 629	} while (retval == 0);
 630
 631	return retval;
 632}
 633
 634static unsigned int uinput_poll(struct file *file, poll_table *wait)
 635{
 636	struct uinput_device *udev = file->private_data;
 637
 638	poll_wait(file, &udev->waitq, wait);
 639
 640	if (udev->head != udev->tail)
 641		return POLLIN | POLLRDNORM;
 642
 643	return 0;
 644}
 645
 646static int uinput_release(struct inode *inode, struct file *file)
 647{
 648	struct uinput_device *udev = file->private_data;
 649
 650	uinput_destroy_device(udev);
 651	kfree(udev);
 652
 653	return 0;
 654}
 655
 656#ifdef CONFIG_COMPAT
 657struct uinput_ff_upload_compat {
 658	__u32			request_id;
 659	__s32			retval;
 660	struct ff_effect_compat	effect;
 661	struct ff_effect_compat	old;
 662};
 663
 664static int uinput_ff_upload_to_user(char __user *buffer,
 665				    const struct uinput_ff_upload *ff_up)
 666{
 667	if (in_compat_syscall()) {
 668		struct uinput_ff_upload_compat ff_up_compat;
 669
 670		ff_up_compat.request_id = ff_up->request_id;
 671		ff_up_compat.retval = ff_up->retval;
 672		/*
 673		 * It so happens that the pointer that gives us the trouble
 674		 * is the last field in the structure. Since we don't support
 675		 * custom waveforms in uinput anyway we can just copy the whole
 676		 * thing (to the compat size) and ignore the pointer.
 677		 */
 678		memcpy(&ff_up_compat.effect, &ff_up->effect,
 679			sizeof(struct ff_effect_compat));
 680		memcpy(&ff_up_compat.old, &ff_up->old,
 681			sizeof(struct ff_effect_compat));
 682
 683		if (copy_to_user(buffer, &ff_up_compat,
 684				 sizeof(struct uinput_ff_upload_compat)))
 685			return -EFAULT;
 686	} else {
 687		if (copy_to_user(buffer, ff_up,
 688				 sizeof(struct uinput_ff_upload)))
 689			return -EFAULT;
 690	}
 691
 692	return 0;
 693}
 694
 695static int uinput_ff_upload_from_user(const char __user *buffer,
 696				      struct uinput_ff_upload *ff_up)
 697{
 698	if (in_compat_syscall()) {
 699		struct uinput_ff_upload_compat ff_up_compat;
 700
 701		if (copy_from_user(&ff_up_compat, buffer,
 702				   sizeof(struct uinput_ff_upload_compat)))
 703			return -EFAULT;
 704
 705		ff_up->request_id = ff_up_compat.request_id;
 706		ff_up->retval = ff_up_compat.retval;
 707		memcpy(&ff_up->effect, &ff_up_compat.effect,
 708			sizeof(struct ff_effect_compat));
 709		memcpy(&ff_up->old, &ff_up_compat.old,
 710			sizeof(struct ff_effect_compat));
 711
 712	} else {
 713		if (copy_from_user(ff_up, buffer,
 714				   sizeof(struct uinput_ff_upload)))
 715			return -EFAULT;
 716	}
 717
 718	return 0;
 719}
 720
 721#else
 722
 723static int uinput_ff_upload_to_user(char __user *buffer,
 724				    const struct uinput_ff_upload *ff_up)
 725{
 726	if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
 727		return -EFAULT;
 728
 729	return 0;
 730}
 731
 732static int uinput_ff_upload_from_user(const char __user *buffer,
 733				      struct uinput_ff_upload *ff_up)
 734{
 735	if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
 736		return -EFAULT;
 737
 738	return 0;
 739}
 740
 741#endif
 742
 743#define uinput_set_bit(_arg, _bit, _max)		\
 744({							\
 745	int __ret = 0;					\
 746	if (udev->state == UIST_CREATED)		\
 747		__ret =  -EINVAL;			\
 748	else if ((_arg) > (_max))			\
 749		__ret = -EINVAL;			\
 750	else set_bit((_arg), udev->dev->_bit);		\
 751	__ret;						\
 752})
 753
 754static int uinput_str_to_user(void __user *dest, const char *str,
 755			      unsigned int maxlen)
 756{
 757	char __user *p = dest;
 758	int len, ret;
 759
 760	if (!str)
 761		return -ENOENT;
 762
 763	if (maxlen == 0)
 764		return -EINVAL;
 765
 766	len = strlen(str) + 1;
 767	if (len > maxlen)
 768		len = maxlen;
 769
 770	ret = copy_to_user(p, str, len);
 771	if (ret)
 772		return -EFAULT;
 773
 774	/* force terminating '\0' */
 775	ret = put_user(0, p + len - 1);
 776	return ret ? -EFAULT : len;
 777}
 778
 779static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
 780				 unsigned long arg, void __user *p)
 781{
 782	int			retval;
 783	struct uinput_device	*udev = file->private_data;
 784	struct uinput_ff_upload ff_up;
 785	struct uinput_ff_erase  ff_erase;
 786	struct uinput_request   *req;
 787	char			*phys;
 788	const char		*name;
 789	unsigned int		size;
 790
 791	retval = mutex_lock_interruptible(&udev->mutex);
 792	if (retval)
 793		return retval;
 794
 795	if (!udev->dev) {
 796		retval = uinput_allocate_device(udev);
 797		if (retval)
 798			goto out;
 799	}
 800
 801	switch (cmd) {
 802		case UI_GET_VERSION:
 803			if (put_user(UINPUT_VERSION,
 804				     (unsigned int __user *)p))
 805				retval = -EFAULT;
 806			goto out;
 807
 808		case UI_DEV_CREATE:
 809			retval = uinput_create_device(udev);
 810			goto out;
 811
 812		case UI_DEV_DESTROY:
 813			uinput_destroy_device(udev);
 814			goto out;
 815
 816		case UI_DEV_SETUP:
 817			retval = uinput_dev_setup(udev, p);
 818			goto out;
 819
 820		/* UI_ABS_SETUP is handled in the variable size ioctls */
 821
 822		case UI_SET_EVBIT:
 823			retval = uinput_set_bit(arg, evbit, EV_MAX);
 824			goto out;
 825
 826		case UI_SET_KEYBIT:
 827			retval = uinput_set_bit(arg, keybit, KEY_MAX);
 828			goto out;
 829
 830		case UI_SET_RELBIT:
 831			retval = uinput_set_bit(arg, relbit, REL_MAX);
 832			goto out;
 833
 834		case UI_SET_ABSBIT:
 835			retval = uinput_set_bit(arg, absbit, ABS_MAX);
 836			goto out;
 837
 838		case UI_SET_MSCBIT:
 839			retval = uinput_set_bit(arg, mscbit, MSC_MAX);
 840			goto out;
 841
 842		case UI_SET_LEDBIT:
 843			retval = uinput_set_bit(arg, ledbit, LED_MAX);
 844			goto out;
 845
 846		case UI_SET_SNDBIT:
 847			retval = uinput_set_bit(arg, sndbit, SND_MAX);
 848			goto out;
 849
 850		case UI_SET_FFBIT:
 851			retval = uinput_set_bit(arg, ffbit, FF_MAX);
 852			goto out;
 853
 854		case UI_SET_SWBIT:
 855			retval = uinput_set_bit(arg, swbit, SW_MAX);
 856			goto out;
 857
 858		case UI_SET_PROPBIT:
 859			retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
 860			goto out;
 861
 862		case UI_SET_PHYS:
 863			if (udev->state == UIST_CREATED) {
 864				retval = -EINVAL;
 865				goto out;
 866			}
 867
 868			phys = strndup_user(p, 1024);
 869			if (IS_ERR(phys)) {
 870				retval = PTR_ERR(phys);
 871				goto out;
 872			}
 873
 874			kfree(udev->dev->phys);
 875			udev->dev->phys = phys;
 876			goto out;
 877
 878		case UI_BEGIN_FF_UPLOAD:
 879			retval = uinput_ff_upload_from_user(p, &ff_up);
 880			if (retval)
 881				goto out;
 882
 883			req = uinput_request_find(udev, ff_up.request_id);
 884			if (!req || req->code != UI_FF_UPLOAD ||
 885			    !req->u.upload.effect) {
 886				retval = -EINVAL;
 887				goto out;
 888			}
 889
 890			ff_up.retval = 0;
 891			ff_up.effect = *req->u.upload.effect;
 892			if (req->u.upload.old)
 893				ff_up.old = *req->u.upload.old;
 894			else
 895				memset(&ff_up.old, 0, sizeof(struct ff_effect));
 896
 897			retval = uinput_ff_upload_to_user(p, &ff_up);
 898			goto out;
 899
 900		case UI_BEGIN_FF_ERASE:
 901			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 902				retval = -EFAULT;
 903				goto out;
 904			}
 905
 906			req = uinput_request_find(udev, ff_erase.request_id);
 907			if (!req || req->code != UI_FF_ERASE) {
 908				retval = -EINVAL;
 909				goto out;
 910			}
 911
 912			ff_erase.retval = 0;
 913			ff_erase.effect_id = req->u.effect_id;
 914			if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
 915				retval = -EFAULT;
 916				goto out;
 917			}
 918
 919			goto out;
 920
 921		case UI_END_FF_UPLOAD:
 922			retval = uinput_ff_upload_from_user(p, &ff_up);
 923			if (retval)
 924				goto out;
 925
 926			req = uinput_request_find(udev, ff_up.request_id);
 927			if (!req || req->code != UI_FF_UPLOAD ||
 928			    !req->u.upload.effect) {
 929				retval = -EINVAL;
 930				goto out;
 931			}
 932
 933			req->retval = ff_up.retval;
 934			uinput_request_done(udev, req);
 935			goto out;
 936
 937		case UI_END_FF_ERASE:
 938			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 939				retval = -EFAULT;
 940				goto out;
 941			}
 942
 943			req = uinput_request_find(udev, ff_erase.request_id);
 944			if (!req || req->code != UI_FF_ERASE) {
 945				retval = -EINVAL;
 946				goto out;
 947			}
 948
 949			req->retval = ff_erase.retval;
 950			uinput_request_done(udev, req);
 951			goto out;
 952	}
 953
 954	size = _IOC_SIZE(cmd);
 955
 956	/* Now check variable-length commands */
 957	switch (cmd & ~IOCSIZE_MASK) {
 958	case UI_GET_SYSNAME(0):
 959		if (udev->state != UIST_CREATED) {
 960			retval = -ENOENT;
 961			goto out;
 962		}
 963		name = dev_name(&udev->dev->dev);
 964		retval = uinput_str_to_user(p, name, size);
 965		goto out;
 966
 967	case UI_ABS_SETUP & ~IOCSIZE_MASK:
 968		retval = uinput_abs_setup(udev, p, size);
 969		goto out;
 970	}
 971
 972	retval = -EINVAL;
 973 out:
 974	mutex_unlock(&udev->mutex);
 975	return retval;
 976}
 977
 978static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 979{
 980	return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
 981}
 982
 983#ifdef CONFIG_COMPAT
 
 
 
 984static long uinput_compat_ioctl(struct file *file,
 985				unsigned int cmd, unsigned long arg)
 986{
 
 
 
 987	return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
 988}
 989#endif
 990
 991static const struct file_operations uinput_fops = {
 992	.owner		= THIS_MODULE,
 993	.open		= uinput_open,
 994	.release	= uinput_release,
 995	.read		= uinput_read,
 996	.write		= uinput_write,
 997	.poll		= uinput_poll,
 998	.unlocked_ioctl	= uinput_ioctl,
 999#ifdef CONFIG_COMPAT
1000	.compat_ioctl	= uinput_compat_ioctl,
1001#endif
1002	.llseek		= no_llseek,
1003};
1004
1005static struct miscdevice uinput_misc = {
1006	.fops		= &uinput_fops,
1007	.minor		= UINPUT_MINOR,
1008	.name		= UINPUT_NAME,
1009};
 
 
1010MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
1011MODULE_ALIAS("devname:" UINPUT_NAME);
1012
1013static int __init uinput_init(void)
1014{
1015	return misc_register(&uinput_misc);
1016}
1017
1018static void __exit uinput_exit(void)
1019{
1020	misc_deregister(&uinput_misc);
1021}
1022
1023MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
1024MODULE_DESCRIPTION("User level driver support for input subsystem");
1025MODULE_LICENSE("GPL");
1026MODULE_VERSION("0.3");
1027
1028module_init(uinput_init);
1029module_exit(uinput_exit);
v4.10.11
   1/*
   2 *  User level driver support for input subsystem
   3 *
   4 * Heavily based on evdev.c by Vojtech Pavlik
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program; if not, write to the Free Software
  18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19 *
  20 * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
  21 *
  22 * Changes/Revisions:
  23 *	0.4	01/09/2014 (Benjamin Tissoires <benjamin.tissoires@redhat.com>)
  24 *		- add UI_GET_SYSNAME ioctl
  25 *	0.3	09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>)
  26 *		- updated ff support for the changes in kernel interface
  27 *		- added MODULE_VERSION
  28 *	0.2	16/10/2004 (Micah Dowty <micah@navi.cx>)
  29 *		- added force feedback support
  30 *              - added UI_SET_PHYS
  31 *	0.1	20/06/2002
  32 *		- first public version
  33 */
  34#include <linux/poll.h>
  35#include <linux/sched.h>
  36#include <linux/slab.h>
  37#include <linux/module.h>
  38#include <linux/init.h>
  39#include <linux/fs.h>
  40#include <linux/miscdevice.h>
  41#include <linux/uinput.h>
  42#include <linux/input/mt.h>
  43#include "../input-compat.h"
  44
  45static int uinput_dev_event(struct input_dev *dev,
  46			    unsigned int type, unsigned int code, int value)
  47{
  48	struct uinput_device	*udev = input_get_drvdata(dev);
  49
  50	udev->buff[udev->head].type = type;
  51	udev->buff[udev->head].code = code;
  52	udev->buff[udev->head].value = value;
  53	do_gettimeofday(&udev->buff[udev->head].time);
  54	udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
  55
  56	wake_up_interruptible(&udev->waitq);
  57
  58	return 0;
  59}
  60
  61/* Atomically allocate an ID for the given request. Returns 0 on success. */
  62static bool uinput_request_alloc_id(struct uinput_device *udev,
  63				    struct uinput_request *request)
  64{
  65	unsigned int id;
  66	bool reserved = false;
  67
  68	spin_lock(&udev->requests_lock);
  69
  70	for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
  71		if (!udev->requests[id]) {
  72			request->id = id;
  73			udev->requests[id] = request;
  74			reserved = true;
  75			break;
  76		}
  77	}
  78
  79	spin_unlock(&udev->requests_lock);
  80	return reserved;
  81}
  82
  83static struct uinput_request *uinput_request_find(struct uinput_device *udev,
  84						  unsigned int id)
  85{
  86	/* Find an input request, by ID. Returns NULL if the ID isn't valid. */
  87	if (id >= UINPUT_NUM_REQUESTS)
  88		return NULL;
  89
  90	return udev->requests[id];
  91}
  92
  93static int uinput_request_reserve_slot(struct uinput_device *udev,
  94				       struct uinput_request *request)
  95{
  96	/* Allocate slot. If none are available right away, wait. */
  97	return wait_event_interruptible(udev->requests_waitq,
  98					uinput_request_alloc_id(udev, request));
  99}
 100
 101static void uinput_request_done(struct uinput_device *udev,
 102				struct uinput_request *request)
 103{
 104	/* Mark slot as available */
 105	udev->requests[request->id] = NULL;
 106	wake_up(&udev->requests_waitq);
 107
 108	complete(&request->done);
 109}
 110
 111static int uinput_request_send(struct uinput_device *udev,
 112			       struct uinput_request *request)
 113{
 114	int retval;
 115
 116	retval = mutex_lock_interruptible(&udev->mutex);
 117	if (retval)
 118		return retval;
 119
 120	if (udev->state != UIST_CREATED) {
 121		retval = -ENODEV;
 122		goto out;
 123	}
 124
 125	init_completion(&request->done);
 126
 127	/*
 128	 * Tell our userspace application about this new request
 129	 * by queueing an input event.
 130	 */
 131	uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
 132
 133 out:
 134	mutex_unlock(&udev->mutex);
 135	return retval;
 136}
 137
 138static int uinput_request_submit(struct uinput_device *udev,
 139				 struct uinput_request *request)
 140{
 141	int error;
 142
 143	error = uinput_request_reserve_slot(udev, request);
 144	if (error)
 145		return error;
 146
 147	error = uinput_request_send(udev, request);
 148	if (error) {
 149		uinput_request_done(udev, request);
 150		return error;
 151	}
 152
 153	wait_for_completion(&request->done);
 154	return request->retval;
 155}
 156
 157/*
 158 * Fail all outstanding requests so handlers don't wait for the userspace
 159 * to finish processing them.
 160 */
 161static void uinput_flush_requests(struct uinput_device *udev)
 162{
 163	struct uinput_request *request;
 164	int i;
 165
 166	spin_lock(&udev->requests_lock);
 167
 168	for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
 169		request = udev->requests[i];
 170		if (request) {
 171			request->retval = -ENODEV;
 172			uinput_request_done(udev, request);
 173		}
 174	}
 175
 176	spin_unlock(&udev->requests_lock);
 177}
 178
 179static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
 180{
 181	uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
 182}
 183
 184static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
 185{
 186	uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
 187}
 188
 189static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
 190{
 191	return uinput_dev_event(dev, EV_FF, effect_id, value);
 192}
 193
 194static int uinput_dev_upload_effect(struct input_dev *dev,
 195				    struct ff_effect *effect,
 196				    struct ff_effect *old)
 197{
 198	struct uinput_device *udev = input_get_drvdata(dev);
 199	struct uinput_request request;
 200
 201	/*
 202	 * uinput driver does not currently support periodic effects with
 203	 * custom waveform since it does not have a way to pass buffer of
 204	 * samples (custom_data) to userspace. If ever there is a device
 205	 * supporting custom waveforms we would need to define an additional
 206	 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
 207	 */
 208	if (effect->type == FF_PERIODIC &&
 209			effect->u.periodic.waveform == FF_CUSTOM)
 210		return -EINVAL;
 211
 212	request.code = UI_FF_UPLOAD;
 213	request.u.upload.effect = effect;
 214	request.u.upload.old = old;
 215
 216	return uinput_request_submit(udev, &request);
 217}
 218
 219static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
 220{
 221	struct uinput_device *udev = input_get_drvdata(dev);
 222	struct uinput_request request;
 223
 224	if (!test_bit(EV_FF, dev->evbit))
 225		return -ENOSYS;
 226
 227	request.code = UI_FF_ERASE;
 228	request.u.effect_id = effect_id;
 229
 230	return uinput_request_submit(udev, &request);
 231}
 232
 233static void uinput_destroy_device(struct uinput_device *udev)
 234{
 235	const char *name, *phys;
 236	struct input_dev *dev = udev->dev;
 237	enum uinput_state old_state = udev->state;
 238
 239	udev->state = UIST_NEW_DEVICE;
 240
 241	if (dev) {
 242		name = dev->name;
 243		phys = dev->phys;
 244		if (old_state == UIST_CREATED) {
 245			uinput_flush_requests(udev);
 246			input_unregister_device(dev);
 247		} else {
 248			input_free_device(dev);
 249		}
 250		kfree(name);
 251		kfree(phys);
 252		udev->dev = NULL;
 253	}
 254}
 255
 256static int uinput_create_device(struct uinput_device *udev)
 257{
 258	struct input_dev *dev = udev->dev;
 259	int error, nslot;
 260
 261	if (udev->state != UIST_SETUP_COMPLETE) {
 262		printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
 263		return -EINVAL;
 264	}
 265
 266	if (test_bit(EV_ABS, dev->evbit)) {
 267		input_alloc_absinfo(dev);
 268		if (!dev->absinfo) {
 269			error = -EINVAL;
 270			goto fail1;
 271		}
 272
 273		if (test_bit(ABS_MT_SLOT, dev->absbit)) {
 274			nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
 275			error = input_mt_init_slots(dev, nslot, 0);
 276			if (error)
 277				goto fail1;
 278		} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
 279			input_set_events_per_packet(dev, 60);
 280		}
 281	}
 282
 283	if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) {
 284		printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n",
 285			UINPUT_NAME);
 286		error = -EINVAL;
 287		goto fail1;
 288	}
 289
 290	if (udev->ff_effects_max) {
 291		error = input_ff_create(dev, udev->ff_effects_max);
 292		if (error)
 293			goto fail1;
 294
 295		dev->ff->upload = uinput_dev_upload_effect;
 296		dev->ff->erase = uinput_dev_erase_effect;
 297		dev->ff->playback = uinput_dev_playback;
 298		dev->ff->set_gain = uinput_dev_set_gain;
 299		dev->ff->set_autocenter = uinput_dev_set_autocenter;
 300	}
 301
 302	error = input_register_device(udev->dev);
 303	if (error)
 304		goto fail2;
 305
 306	udev->state = UIST_CREATED;
 307
 308	return 0;
 309
 310 fail2:	input_ff_destroy(dev);
 311 fail1: uinput_destroy_device(udev);
 312	return error;
 313}
 314
 315static int uinput_open(struct inode *inode, struct file *file)
 316{
 317	struct uinput_device *newdev;
 318
 319	newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
 320	if (!newdev)
 321		return -ENOMEM;
 322
 323	mutex_init(&newdev->mutex);
 324	spin_lock_init(&newdev->requests_lock);
 325	init_waitqueue_head(&newdev->requests_waitq);
 326	init_waitqueue_head(&newdev->waitq);
 327	newdev->state = UIST_NEW_DEVICE;
 328
 329	file->private_data = newdev;
 330	nonseekable_open(inode, file);
 331
 332	return 0;
 333}
 334
 335static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code,
 336				   const struct input_absinfo *abs)
 337{
 338	int min, max;
 339
 340	min = abs->minimum;
 341	max = abs->maximum;
 342
 343	if ((min != 0 || max != 0) && max <= min) {
 344		printk(KERN_DEBUG
 345		       "%s: invalid abs[%02x] min:%d max:%d\n",
 346		       UINPUT_NAME, code, min, max);
 347		return -EINVAL;
 348	}
 349
 350	if (abs->flat > max - min) {
 351		printk(KERN_DEBUG
 352		       "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n",
 353		       UINPUT_NAME, code, abs->flat, min, max);
 354		return -EINVAL;
 355	}
 356
 357	return 0;
 358}
 359
 360static int uinput_validate_absbits(struct input_dev *dev)
 361{
 362	unsigned int cnt;
 363	int error;
 364
 365	if (!test_bit(EV_ABS, dev->evbit))
 366		return 0;
 367
 368	/*
 369	 * Check if absmin/absmax/absfuzz/absflat are sane.
 370	 */
 371
 372	for_each_set_bit(cnt, dev->absbit, ABS_CNT) {
 373		if (!dev->absinfo)
 374			return -EINVAL;
 375
 376		error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]);
 377		if (error)
 378			return error;
 379	}
 380
 381	return 0;
 382}
 383
 384static int uinput_allocate_device(struct uinput_device *udev)
 385{
 386	udev->dev = input_allocate_device();
 387	if (!udev->dev)
 388		return -ENOMEM;
 389
 390	udev->dev->event = uinput_dev_event;
 391	input_set_drvdata(udev->dev, udev);
 392
 393	return 0;
 394}
 395
 396static int uinput_dev_setup(struct uinput_device *udev,
 397			    struct uinput_setup __user *arg)
 398{
 399	struct uinput_setup setup;
 400	struct input_dev *dev;
 401
 402	if (udev->state == UIST_CREATED)
 403		return -EINVAL;
 404
 405	if (copy_from_user(&setup, arg, sizeof(setup)))
 406		return -EFAULT;
 407
 408	if (!setup.name[0])
 409		return -EINVAL;
 410
 411	dev = udev->dev;
 412	dev->id = setup.id;
 413	udev->ff_effects_max = setup.ff_effects_max;
 414
 415	kfree(dev->name);
 416	dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL);
 417	if (!dev->name)
 418		return -ENOMEM;
 419
 420	udev->state = UIST_SETUP_COMPLETE;
 421	return 0;
 422}
 423
 424static int uinput_abs_setup(struct uinput_device *udev,
 425			    struct uinput_setup __user *arg, size_t size)
 426{
 427	struct uinput_abs_setup setup = {};
 428	struct input_dev *dev;
 429	int error;
 430
 431	if (size > sizeof(setup))
 432		return -E2BIG;
 433
 434	if (udev->state == UIST_CREATED)
 435		return -EINVAL;
 436
 437	if (copy_from_user(&setup, arg, size))
 438		return -EFAULT;
 439
 440	if (setup.code > ABS_MAX)
 441		return -ERANGE;
 442
 443	dev = udev->dev;
 444
 445	error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo);
 446	if (error)
 447		return error;
 448
 449	input_alloc_absinfo(dev);
 450	if (!dev->absinfo)
 451		return -ENOMEM;
 452
 453	set_bit(setup.code, dev->absbit);
 454	dev->absinfo[setup.code] = setup.absinfo;
 455	return 0;
 456}
 457
 458/* legacy setup via write() */
 459static int uinput_setup_device_legacy(struct uinput_device *udev,
 460				      const char __user *buffer, size_t count)
 461{
 462	struct uinput_user_dev	*user_dev;
 463	struct input_dev	*dev;
 464	int			i;
 465	int			retval;
 466
 467	if (count != sizeof(struct uinput_user_dev))
 468		return -EINVAL;
 469
 470	if (!udev->dev) {
 471		retval = uinput_allocate_device(udev);
 472		if (retval)
 473			return retval;
 474	}
 475
 476	dev = udev->dev;
 477
 478	user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
 479	if (IS_ERR(user_dev))
 480		return PTR_ERR(user_dev);
 481
 482	udev->ff_effects_max = user_dev->ff_effects_max;
 483
 484	/* Ensure name is filled in */
 485	if (!user_dev->name[0]) {
 486		retval = -EINVAL;
 487		goto exit;
 488	}
 489
 490	kfree(dev->name);
 491	dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
 492			     GFP_KERNEL);
 493	if (!dev->name) {
 494		retval = -ENOMEM;
 495		goto exit;
 496	}
 497
 498	dev->id.bustype	= user_dev->id.bustype;
 499	dev->id.vendor	= user_dev->id.vendor;
 500	dev->id.product	= user_dev->id.product;
 501	dev->id.version	= user_dev->id.version;
 502
 503	for (i = 0; i < ABS_CNT; i++) {
 504		input_abs_set_max(dev, i, user_dev->absmax[i]);
 505		input_abs_set_min(dev, i, user_dev->absmin[i]);
 506		input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
 507		input_abs_set_flat(dev, i, user_dev->absflat[i]);
 508	}
 509
 510	retval = uinput_validate_absbits(dev);
 511	if (retval < 0)
 512		goto exit;
 513
 514	udev->state = UIST_SETUP_COMPLETE;
 515	retval = count;
 516
 517 exit:
 518	kfree(user_dev);
 519	return retval;
 520}
 521
 522static ssize_t uinput_inject_events(struct uinput_device *udev,
 523				    const char __user *buffer, size_t count)
 524{
 525	struct input_event ev;
 526	size_t bytes = 0;
 527
 528	if (count != 0 && count < input_event_size())
 529		return -EINVAL;
 530
 531	while (bytes + input_event_size() <= count) {
 532		/*
 533		 * Note that even if some events were fetched successfully
 534		 * we are still going to return EFAULT instead of partial
 535		 * count to let userspace know that it got it's buffers
 536		 * all wrong.
 537		 */
 538		if (input_event_from_user(buffer + bytes, &ev))
 539			return -EFAULT;
 540
 541		input_event(udev->dev, ev.type, ev.code, ev.value);
 542		bytes += input_event_size();
 543	}
 544
 545	return bytes;
 546}
 547
 548static ssize_t uinput_write(struct file *file, const char __user *buffer,
 549			    size_t count, loff_t *ppos)
 550{
 551	struct uinput_device *udev = file->private_data;
 552	int retval;
 553
 554	if (count == 0)
 555		return 0;
 556
 557	retval = mutex_lock_interruptible(&udev->mutex);
 558	if (retval)
 559		return retval;
 560
 561	retval = udev->state == UIST_CREATED ?
 562			uinput_inject_events(udev, buffer, count) :
 563			uinput_setup_device_legacy(udev, buffer, count);
 564
 565	mutex_unlock(&udev->mutex);
 566
 567	return retval;
 568}
 569
 570static bool uinput_fetch_next_event(struct uinput_device *udev,
 571				    struct input_event *event)
 572{
 573	bool have_event;
 574
 575	spin_lock_irq(&udev->dev->event_lock);
 576
 577	have_event = udev->head != udev->tail;
 578	if (have_event) {
 579		*event = udev->buff[udev->tail];
 580		udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
 581	}
 582
 583	spin_unlock_irq(&udev->dev->event_lock);
 584
 585	return have_event;
 586}
 587
 588static ssize_t uinput_events_to_user(struct uinput_device *udev,
 589				     char __user *buffer, size_t count)
 590{
 591	struct input_event event;
 592	size_t read = 0;
 593
 594	while (read + input_event_size() <= count &&
 595	       uinput_fetch_next_event(udev, &event)) {
 596
 597		if (input_event_to_user(buffer + read, &event))
 598			return -EFAULT;
 599
 600		read += input_event_size();
 601	}
 602
 603	return read;
 604}
 605
 606static ssize_t uinput_read(struct file *file, char __user *buffer,
 607			   size_t count, loff_t *ppos)
 608{
 609	struct uinput_device *udev = file->private_data;
 610	ssize_t retval;
 611
 612	if (count != 0 && count < input_event_size())
 613		return -EINVAL;
 614
 615	do {
 616		retval = mutex_lock_interruptible(&udev->mutex);
 617		if (retval)
 618			return retval;
 619
 620		if (udev->state != UIST_CREATED)
 621			retval = -ENODEV;
 622		else if (udev->head == udev->tail &&
 623			 (file->f_flags & O_NONBLOCK))
 624			retval = -EAGAIN;
 625		else
 626			retval = uinput_events_to_user(udev, buffer, count);
 627
 628		mutex_unlock(&udev->mutex);
 629
 630		if (retval || count == 0)
 631			break;
 632
 633		if (!(file->f_flags & O_NONBLOCK))
 634			retval = wait_event_interruptible(udev->waitq,
 635						  udev->head != udev->tail ||
 636						  udev->state != UIST_CREATED);
 637	} while (retval == 0);
 638
 639	return retval;
 640}
 641
 642static unsigned int uinput_poll(struct file *file, poll_table *wait)
 643{
 644	struct uinput_device *udev = file->private_data;
 645
 646	poll_wait(file, &udev->waitq, wait);
 647
 648	if (udev->head != udev->tail)
 649		return POLLIN | POLLRDNORM;
 650
 651	return 0;
 652}
 653
 654static int uinput_release(struct inode *inode, struct file *file)
 655{
 656	struct uinput_device *udev = file->private_data;
 657
 658	uinput_destroy_device(udev);
 659	kfree(udev);
 660
 661	return 0;
 662}
 663
 664#ifdef CONFIG_COMPAT
 665struct uinput_ff_upload_compat {
 666	__u32			request_id;
 667	__s32			retval;
 668	struct ff_effect_compat	effect;
 669	struct ff_effect_compat	old;
 670};
 671
 672static int uinput_ff_upload_to_user(char __user *buffer,
 673				    const struct uinput_ff_upload *ff_up)
 674{
 675	if (in_compat_syscall()) {
 676		struct uinput_ff_upload_compat ff_up_compat;
 677
 678		ff_up_compat.request_id = ff_up->request_id;
 679		ff_up_compat.retval = ff_up->retval;
 680		/*
 681		 * It so happens that the pointer that gives us the trouble
 682		 * is the last field in the structure. Since we don't support
 683		 * custom waveforms in uinput anyway we can just copy the whole
 684		 * thing (to the compat size) and ignore the pointer.
 685		 */
 686		memcpy(&ff_up_compat.effect, &ff_up->effect,
 687			sizeof(struct ff_effect_compat));
 688		memcpy(&ff_up_compat.old, &ff_up->old,
 689			sizeof(struct ff_effect_compat));
 690
 691		if (copy_to_user(buffer, &ff_up_compat,
 692				 sizeof(struct uinput_ff_upload_compat)))
 693			return -EFAULT;
 694	} else {
 695		if (copy_to_user(buffer, ff_up,
 696				 sizeof(struct uinput_ff_upload)))
 697			return -EFAULT;
 698	}
 699
 700	return 0;
 701}
 702
 703static int uinput_ff_upload_from_user(const char __user *buffer,
 704				      struct uinput_ff_upload *ff_up)
 705{
 706	if (in_compat_syscall()) {
 707		struct uinput_ff_upload_compat ff_up_compat;
 708
 709		if (copy_from_user(&ff_up_compat, buffer,
 710				   sizeof(struct uinput_ff_upload_compat)))
 711			return -EFAULT;
 712
 713		ff_up->request_id = ff_up_compat.request_id;
 714		ff_up->retval = ff_up_compat.retval;
 715		memcpy(&ff_up->effect, &ff_up_compat.effect,
 716			sizeof(struct ff_effect_compat));
 717		memcpy(&ff_up->old, &ff_up_compat.old,
 718			sizeof(struct ff_effect_compat));
 719
 720	} else {
 721		if (copy_from_user(ff_up, buffer,
 722				   sizeof(struct uinput_ff_upload)))
 723			return -EFAULT;
 724	}
 725
 726	return 0;
 727}
 728
 729#else
 730
 731static int uinput_ff_upload_to_user(char __user *buffer,
 732				    const struct uinput_ff_upload *ff_up)
 733{
 734	if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
 735		return -EFAULT;
 736
 737	return 0;
 738}
 739
 740static int uinput_ff_upload_from_user(const char __user *buffer,
 741				      struct uinput_ff_upload *ff_up)
 742{
 743	if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
 744		return -EFAULT;
 745
 746	return 0;
 747}
 748
 749#endif
 750
 751#define uinput_set_bit(_arg, _bit, _max)		\
 752({							\
 753	int __ret = 0;					\
 754	if (udev->state == UIST_CREATED)		\
 755		__ret =  -EINVAL;			\
 756	else if ((_arg) > (_max))			\
 757		__ret = -EINVAL;			\
 758	else set_bit((_arg), udev->dev->_bit);		\
 759	__ret;						\
 760})
 761
 762static int uinput_str_to_user(void __user *dest, const char *str,
 763			      unsigned int maxlen)
 764{
 765	char __user *p = dest;
 766	int len, ret;
 767
 768	if (!str)
 769		return -ENOENT;
 770
 771	if (maxlen == 0)
 772		return -EINVAL;
 773
 774	len = strlen(str) + 1;
 775	if (len > maxlen)
 776		len = maxlen;
 777
 778	ret = copy_to_user(p, str, len);
 779	if (ret)
 780		return -EFAULT;
 781
 782	/* force terminating '\0' */
 783	ret = put_user(0, p + len - 1);
 784	return ret ? -EFAULT : len;
 785}
 786
 787static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
 788				 unsigned long arg, void __user *p)
 789{
 790	int			retval;
 791	struct uinput_device	*udev = file->private_data;
 792	struct uinput_ff_upload ff_up;
 793	struct uinput_ff_erase  ff_erase;
 794	struct uinput_request   *req;
 795	char			*phys;
 796	const char		*name;
 797	unsigned int		size;
 798
 799	retval = mutex_lock_interruptible(&udev->mutex);
 800	if (retval)
 801		return retval;
 802
 803	if (!udev->dev) {
 804		retval = uinput_allocate_device(udev);
 805		if (retval)
 806			goto out;
 807	}
 808
 809	switch (cmd) {
 810		case UI_GET_VERSION:
 811			if (put_user(UINPUT_VERSION,
 812				     (unsigned int __user *)p))
 813				retval = -EFAULT;
 814			goto out;
 815
 816		case UI_DEV_CREATE:
 817			retval = uinput_create_device(udev);
 818			goto out;
 819
 820		case UI_DEV_DESTROY:
 821			uinput_destroy_device(udev);
 822			goto out;
 823
 824		case UI_DEV_SETUP:
 825			retval = uinput_dev_setup(udev, p);
 826			goto out;
 827
 828		/* UI_ABS_SETUP is handled in the variable size ioctls */
 829
 830		case UI_SET_EVBIT:
 831			retval = uinput_set_bit(arg, evbit, EV_MAX);
 832			goto out;
 833
 834		case UI_SET_KEYBIT:
 835			retval = uinput_set_bit(arg, keybit, KEY_MAX);
 836			goto out;
 837
 838		case UI_SET_RELBIT:
 839			retval = uinput_set_bit(arg, relbit, REL_MAX);
 840			goto out;
 841
 842		case UI_SET_ABSBIT:
 843			retval = uinput_set_bit(arg, absbit, ABS_MAX);
 844			goto out;
 845
 846		case UI_SET_MSCBIT:
 847			retval = uinput_set_bit(arg, mscbit, MSC_MAX);
 848			goto out;
 849
 850		case UI_SET_LEDBIT:
 851			retval = uinput_set_bit(arg, ledbit, LED_MAX);
 852			goto out;
 853
 854		case UI_SET_SNDBIT:
 855			retval = uinput_set_bit(arg, sndbit, SND_MAX);
 856			goto out;
 857
 858		case UI_SET_FFBIT:
 859			retval = uinput_set_bit(arg, ffbit, FF_MAX);
 860			goto out;
 861
 862		case UI_SET_SWBIT:
 863			retval = uinput_set_bit(arg, swbit, SW_MAX);
 864			goto out;
 865
 866		case UI_SET_PROPBIT:
 867			retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
 868			goto out;
 869
 870		case UI_SET_PHYS:
 871			if (udev->state == UIST_CREATED) {
 872				retval = -EINVAL;
 873				goto out;
 874			}
 875
 876			phys = strndup_user(p, 1024);
 877			if (IS_ERR(phys)) {
 878				retval = PTR_ERR(phys);
 879				goto out;
 880			}
 881
 882			kfree(udev->dev->phys);
 883			udev->dev->phys = phys;
 884			goto out;
 885
 886		case UI_BEGIN_FF_UPLOAD:
 887			retval = uinput_ff_upload_from_user(p, &ff_up);
 888			if (retval)
 889				goto out;
 890
 891			req = uinput_request_find(udev, ff_up.request_id);
 892			if (!req || req->code != UI_FF_UPLOAD ||
 893			    !req->u.upload.effect) {
 894				retval = -EINVAL;
 895				goto out;
 896			}
 897
 898			ff_up.retval = 0;
 899			ff_up.effect = *req->u.upload.effect;
 900			if (req->u.upload.old)
 901				ff_up.old = *req->u.upload.old;
 902			else
 903				memset(&ff_up.old, 0, sizeof(struct ff_effect));
 904
 905			retval = uinput_ff_upload_to_user(p, &ff_up);
 906			goto out;
 907
 908		case UI_BEGIN_FF_ERASE:
 909			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 910				retval = -EFAULT;
 911				goto out;
 912			}
 913
 914			req = uinput_request_find(udev, ff_erase.request_id);
 915			if (!req || req->code != UI_FF_ERASE) {
 916				retval = -EINVAL;
 917				goto out;
 918			}
 919
 920			ff_erase.retval = 0;
 921			ff_erase.effect_id = req->u.effect_id;
 922			if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
 923				retval = -EFAULT;
 924				goto out;
 925			}
 926
 927			goto out;
 928
 929		case UI_END_FF_UPLOAD:
 930			retval = uinput_ff_upload_from_user(p, &ff_up);
 931			if (retval)
 932				goto out;
 933
 934			req = uinput_request_find(udev, ff_up.request_id);
 935			if (!req || req->code != UI_FF_UPLOAD ||
 936			    !req->u.upload.effect) {
 937				retval = -EINVAL;
 938				goto out;
 939			}
 940
 941			req->retval = ff_up.retval;
 942			uinput_request_done(udev, req);
 943			goto out;
 944
 945		case UI_END_FF_ERASE:
 946			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 947				retval = -EFAULT;
 948				goto out;
 949			}
 950
 951			req = uinput_request_find(udev, ff_erase.request_id);
 952			if (!req || req->code != UI_FF_ERASE) {
 953				retval = -EINVAL;
 954				goto out;
 955			}
 956
 957			req->retval = ff_erase.retval;
 958			uinput_request_done(udev, req);
 959			goto out;
 960	}
 961
 962	size = _IOC_SIZE(cmd);
 963
 964	/* Now check variable-length commands */
 965	switch (cmd & ~IOCSIZE_MASK) {
 966	case UI_GET_SYSNAME(0):
 967		if (udev->state != UIST_CREATED) {
 968			retval = -ENOENT;
 969			goto out;
 970		}
 971		name = dev_name(&udev->dev->dev);
 972		retval = uinput_str_to_user(p, name, size);
 973		goto out;
 974
 975	case UI_ABS_SETUP & ~IOCSIZE_MASK:
 976		retval = uinput_abs_setup(udev, p, size);
 977		goto out;
 978	}
 979
 980	retval = -EINVAL;
 981 out:
 982	mutex_unlock(&udev->mutex);
 983	return retval;
 984}
 985
 986static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 987{
 988	return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
 989}
 990
 991#ifdef CONFIG_COMPAT
 992
 993#define UI_SET_PHYS_COMPAT	_IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t)
 994
 995static long uinput_compat_ioctl(struct file *file,
 996				unsigned int cmd, unsigned long arg)
 997{
 998	if (cmd == UI_SET_PHYS_COMPAT)
 999		cmd = UI_SET_PHYS;
1000
1001	return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
1002}
1003#endif
1004
1005static const struct file_operations uinput_fops = {
1006	.owner		= THIS_MODULE,
1007	.open		= uinput_open,
1008	.release	= uinput_release,
1009	.read		= uinput_read,
1010	.write		= uinput_write,
1011	.poll		= uinput_poll,
1012	.unlocked_ioctl	= uinput_ioctl,
1013#ifdef CONFIG_COMPAT
1014	.compat_ioctl	= uinput_compat_ioctl,
1015#endif
1016	.llseek		= no_llseek,
1017};
1018
1019static struct miscdevice uinput_misc = {
1020	.fops		= &uinput_fops,
1021	.minor		= UINPUT_MINOR,
1022	.name		= UINPUT_NAME,
1023};
1024module_misc_device(uinput_misc);
1025
1026MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
1027MODULE_ALIAS("devname:" UINPUT_NAME);
1028
 
 
 
 
 
 
 
 
 
 
1029MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
1030MODULE_DESCRIPTION("User level driver support for input subsystem");
1031MODULE_LICENSE("GPL");
1032MODULE_VERSION("0.3");