Linux Audio

Check our new training course

Loading...
v3.15
 
  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;
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 (udev->ff_effects_max) {
267		error = input_ff_create(dev, udev->ff_effects_max);
268		if (error)
269			goto fail1;
270
271		dev->ff->upload = uinput_dev_upload_effect;
272		dev->ff->erase = uinput_dev_erase_effect;
273		dev->ff->playback = uinput_dev_playback;
274		dev->ff->set_gain = uinput_dev_set_gain;
275		dev->ff->set_autocenter = uinput_dev_set_autocenter;
 
 
 
 
 
 
276	}
277
 
 
 
 
278	error = input_register_device(udev->dev);
279	if (error)
280		goto fail2;
281
282	udev->state = UIST_CREATED;
283
284	return 0;
285
286 fail2:	input_ff_destroy(dev);
287 fail1: uinput_destroy_device(udev);
288	return error;
289}
290
291static int uinput_open(struct inode *inode, struct file *file)
292{
293	struct uinput_device *newdev;
294
295	newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
296	if (!newdev)
297		return -ENOMEM;
298
299	mutex_init(&newdev->mutex);
300	spin_lock_init(&newdev->requests_lock);
301	init_waitqueue_head(&newdev->requests_waitq);
302	init_waitqueue_head(&newdev->waitq);
303	newdev->state = UIST_NEW_DEVICE;
304
305	file->private_data = newdev;
306	nonseekable_open(inode, file);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
307
308	return 0;
309}
310
311static int uinput_validate_absbits(struct input_dev *dev)
312{
313	unsigned int cnt;
314	int retval = 0;
315
316	for (cnt = 0; cnt < ABS_CNT; cnt++) {
317		int min, max;
318		if (!test_bit(cnt, dev->absbit))
319			continue;
320
321		min = input_abs_get_min(dev, cnt);
322		max = input_abs_get_max(dev, cnt);
323
324		if ((min != 0 || max != 0) && max <= min) {
325			printk(KERN_DEBUG
326				"%s: invalid abs[%02x] min:%d max:%d\n",
327				UINPUT_NAME, cnt,
328				input_abs_get_min(dev, cnt),
329				input_abs_get_max(dev, cnt));
330			retval = -EINVAL;
331			break;
332		}
333
334		if (input_abs_get_flat(dev, cnt) >
335		    input_abs_get_max(dev, cnt) - input_abs_get_min(dev, cnt)) {
336			printk(KERN_DEBUG
337				"%s: abs_flat #%02x out of range: %d "
338				"(min:%d/max:%d)\n",
339				UINPUT_NAME, cnt,
340				input_abs_get_flat(dev, cnt),
341				input_abs_get_min(dev, cnt),
342				input_abs_get_max(dev, cnt));
343			retval = -EINVAL;
344			break;
345		}
346	}
347	return retval;
 
348}
349
350static int uinput_allocate_device(struct uinput_device *udev)
 
351{
352	udev->dev = input_allocate_device();
353	if (!udev->dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
354		return -ENOMEM;
355
356	udev->dev->event = uinput_dev_event;
357	input_set_drvdata(udev->dev, udev);
 
 
 
 
 
 
 
 
358
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
359	return 0;
360}
361
362static int uinput_setup_device(struct uinput_device *udev,
363			       const char __user *buffer, size_t count)
 
364{
365	struct uinput_user_dev	*user_dev;
366	struct input_dev	*dev;
367	int			i;
368	int			retval;
369
370	if (count != sizeof(struct uinput_user_dev))
371		return -EINVAL;
372
373	if (!udev->dev) {
374		retval = uinput_allocate_device(udev);
375		if (retval)
376			return retval;
377	}
378
379	dev = udev->dev;
380
381	user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
382	if (IS_ERR(user_dev))
383		return PTR_ERR(user_dev);
384
385	udev->ff_effects_max = user_dev->ff_effects_max;
386
387	/* Ensure name is filled in */
388	if (!user_dev->name[0]) {
389		retval = -EINVAL;
390		goto exit;
391	}
392
393	kfree(dev->name);
394	dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
395			     GFP_KERNEL);
396	if (!dev->name) {
397		retval = -ENOMEM;
398		goto exit;
399	}
400
401	dev->id.bustype	= user_dev->id.bustype;
402	dev->id.vendor	= user_dev->id.vendor;
403	dev->id.product	= user_dev->id.product;
404	dev->id.version	= user_dev->id.version;
405
406	for (i = 0; i < ABS_CNT; i++) {
407		input_abs_set_max(dev, i, user_dev->absmax[i]);
408		input_abs_set_min(dev, i, user_dev->absmin[i]);
409		input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
410		input_abs_set_flat(dev, i, user_dev->absflat[i]);
411	}
412
413	/* check if absmin/absmax/absfuzz/absflat are filled as
414	 * told in Documentation/input/input-programming.txt */
415	if (test_bit(EV_ABS, dev->evbit)) {
416		retval = uinput_validate_absbits(dev);
417		if (retval < 0)
418			goto exit;
419		if (test_bit(ABS_MT_SLOT, dev->absbit)) {
420			int nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
421			input_mt_init_slots(dev, nslot, 0);
422		} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
423			input_set_events_per_packet(dev, 60);
424		}
425	}
426
427	udev->state = UIST_SETUP_COMPLETE;
428	retval = count;
429
430 exit:
431	kfree(user_dev);
432	return retval;
433}
434
435static ssize_t uinput_inject_events(struct uinput_device *udev,
436				    const char __user *buffer, size_t count)
437{
438	struct input_event ev;
439	size_t bytes = 0;
440
441	if (count != 0 && count < input_event_size())
442		return -EINVAL;
443
444	while (bytes + input_event_size() <= count) {
445		/*
446		 * Note that even if some events were fetched successfully
447		 * we are still going to return EFAULT instead of partial
448		 * count to let userspace know that it got it's buffers
449		 * all wrong.
450		 */
451		if (input_event_from_user(buffer + bytes, &ev))
452			return -EFAULT;
453
454		input_event(udev->dev, ev.type, ev.code, ev.value);
455		bytes += input_event_size();
 
456	}
457
458	return bytes;
459}
460
461static ssize_t uinput_write(struct file *file, const char __user *buffer,
462			    size_t count, loff_t *ppos)
463{
464	struct uinput_device *udev = file->private_data;
465	int retval;
466
467	if (count == 0)
468		return 0;
469
470	retval = mutex_lock_interruptible(&udev->mutex);
471	if (retval)
472		return retval;
473
474	retval = udev->state == UIST_CREATED ?
475			uinput_inject_events(udev, buffer, count) :
476			uinput_setup_device(udev, buffer, count);
477
478	mutex_unlock(&udev->mutex);
479
480	return retval;
481}
482
483static bool uinput_fetch_next_event(struct uinput_device *udev,
484				    struct input_event *event)
485{
486	bool have_event;
487
488	spin_lock_irq(&udev->dev->event_lock);
489
490	have_event = udev->head != udev->tail;
491	if (have_event) {
492		*event = udev->buff[udev->tail];
493		udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
494	}
495
496	spin_unlock_irq(&udev->dev->event_lock);
497
498	return have_event;
499}
500
501static ssize_t uinput_events_to_user(struct uinput_device *udev,
502				     char __user *buffer, size_t count)
503{
504	struct input_event event;
505	size_t read = 0;
506
507	while (read + input_event_size() <= count &&
508	       uinput_fetch_next_event(udev, &event)) {
509
510		if (input_event_to_user(buffer + read, &event))
511			return -EFAULT;
512
513		read += input_event_size();
514	}
515
516	return read;
517}
518
519static ssize_t uinput_read(struct file *file, char __user *buffer,
520			   size_t count, loff_t *ppos)
521{
522	struct uinput_device *udev = file->private_data;
523	ssize_t retval;
524
525	if (count != 0 && count < input_event_size())
526		return -EINVAL;
527
528	do {
529		retval = mutex_lock_interruptible(&udev->mutex);
530		if (retval)
531			return retval;
532
533		if (udev->state != UIST_CREATED)
534			retval = -ENODEV;
535		else if (udev->head == udev->tail &&
536			 (file->f_flags & O_NONBLOCK))
537			retval = -EAGAIN;
538		else
539			retval = uinput_events_to_user(udev, buffer, count);
540
541		mutex_unlock(&udev->mutex);
542
543		if (retval || count == 0)
544			break;
545
546		if (!(file->f_flags & O_NONBLOCK))
547			retval = wait_event_interruptible(udev->waitq,
548						  udev->head != udev->tail ||
549						  udev->state != UIST_CREATED);
550	} while (retval == 0);
551
552	return retval;
553}
554
555static unsigned int uinput_poll(struct file *file, poll_table *wait)
556{
557	struct uinput_device *udev = file->private_data;
 
558
559	poll_wait(file, &udev->waitq, wait);
560
561	if (udev->head != udev->tail)
562		return POLLIN | POLLRDNORM;
563
564	return 0;
565}
566
567static int uinput_release(struct inode *inode, struct file *file)
568{
569	struct uinput_device *udev = file->private_data;
570
571	uinput_destroy_device(udev);
572	kfree(udev);
573
574	return 0;
575}
576
577#ifdef CONFIG_COMPAT
578struct uinput_ff_upload_compat {
579	__u32			request_id;
580	__s32			retval;
581	struct ff_effect_compat	effect;
582	struct ff_effect_compat	old;
583};
584
585static int uinput_ff_upload_to_user(char __user *buffer,
586				    const struct uinput_ff_upload *ff_up)
587{
588	if (INPUT_COMPAT_TEST) {
589		struct uinput_ff_upload_compat ff_up_compat;
590
591		ff_up_compat.request_id = ff_up->request_id;
592		ff_up_compat.retval = ff_up->retval;
593		/*
594		 * It so happens that the pointer that gives us the trouble
595		 * is the last field in the structure. Since we don't support
596		 * custom waveforms in uinput anyway we can just copy the whole
597		 * thing (to the compat size) and ignore the pointer.
598		 */
599		memcpy(&ff_up_compat.effect, &ff_up->effect,
600			sizeof(struct ff_effect_compat));
601		memcpy(&ff_up_compat.old, &ff_up->old,
602			sizeof(struct ff_effect_compat));
603
604		if (copy_to_user(buffer, &ff_up_compat,
605				 sizeof(struct uinput_ff_upload_compat)))
606			return -EFAULT;
607	} else {
608		if (copy_to_user(buffer, ff_up,
609				 sizeof(struct uinput_ff_upload)))
610			return -EFAULT;
611	}
612
613	return 0;
614}
615
616static int uinput_ff_upload_from_user(const char __user *buffer,
617				      struct uinput_ff_upload *ff_up)
618{
619	if (INPUT_COMPAT_TEST) {
620		struct uinput_ff_upload_compat ff_up_compat;
621
622		if (copy_from_user(&ff_up_compat, buffer,
623				   sizeof(struct uinput_ff_upload_compat)))
624			return -EFAULT;
625
626		ff_up->request_id = ff_up_compat.request_id;
627		ff_up->retval = ff_up_compat.retval;
628		memcpy(&ff_up->effect, &ff_up_compat.effect,
629			sizeof(struct ff_effect_compat));
630		memcpy(&ff_up->old, &ff_up_compat.old,
631			sizeof(struct ff_effect_compat));
632
633	} else {
634		if (copy_from_user(ff_up, buffer,
635				   sizeof(struct uinput_ff_upload)))
636			return -EFAULT;
637	}
638
639	return 0;
640}
641
642#else
643
644static int uinput_ff_upload_to_user(char __user *buffer,
645				    const struct uinput_ff_upload *ff_up)
646{
647	if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
648		return -EFAULT;
649
650	return 0;
651}
652
653static int uinput_ff_upload_from_user(const char __user *buffer,
654				      struct uinput_ff_upload *ff_up)
655{
656	if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
657		return -EFAULT;
658
659	return 0;
660}
661
662#endif
663
664#define uinput_set_bit(_arg, _bit, _max)		\
665({							\
666	int __ret = 0;					\
667	if (udev->state == UIST_CREATED)		\
668		__ret =  -EINVAL;			\
669	else if ((_arg) > (_max))			\
670		__ret = -EINVAL;			\
671	else set_bit((_arg), udev->dev->_bit);		\
672	__ret;						\
673})
674
675static int uinput_str_to_user(void __user *dest, const char *str,
676			      unsigned int maxlen)
677{
678	char __user *p = dest;
679	int len, ret;
680
681	if (!str)
682		return -ENOENT;
683
684	if (maxlen == 0)
685		return -EINVAL;
686
687	len = strlen(str) + 1;
688	if (len > maxlen)
689		len = maxlen;
690
691	ret = copy_to_user(p, str, len);
692	if (ret)
693		return -EFAULT;
694
695	/* force terminating '\0' */
696	ret = put_user(0, p + len - 1);
697	return ret ? -EFAULT : len;
698}
699
700static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
701				 unsigned long arg, void __user *p)
702{
703	int			retval;
704	struct uinput_device	*udev = file->private_data;
705	struct uinput_ff_upload ff_up;
706	struct uinput_ff_erase  ff_erase;
707	struct uinput_request   *req;
708	char			*phys;
709	const char		*name;
710	unsigned int		size;
711
712	retval = mutex_lock_interruptible(&udev->mutex);
713	if (retval)
714		return retval;
715
716	if (!udev->dev) {
717		retval = uinput_allocate_device(udev);
718		if (retval)
 
719			goto out;
 
720	}
721
722	switch (cmd) {
723		case UI_DEV_CREATE:
724			retval = uinput_create_device(udev);
725			goto out;
 
726
727		case UI_DEV_DESTROY:
728			uinput_destroy_device(udev);
729			goto out;
730
731		case UI_SET_EVBIT:
732			retval = uinput_set_bit(arg, evbit, EV_MAX);
733			goto out;
734
735		case UI_SET_KEYBIT:
736			retval = uinput_set_bit(arg, keybit, KEY_MAX);
737			goto out;
738
739		case UI_SET_RELBIT:
740			retval = uinput_set_bit(arg, relbit, REL_MAX);
741			goto out;
742
743		case UI_SET_ABSBIT:
744			retval = uinput_set_bit(arg, absbit, ABS_MAX);
745			goto out;
746
747		case UI_SET_MSCBIT:
748			retval = uinput_set_bit(arg, mscbit, MSC_MAX);
749			goto out;
750
751		case UI_SET_LEDBIT:
752			retval = uinput_set_bit(arg, ledbit, LED_MAX);
753			goto out;
754
755		case UI_SET_SNDBIT:
756			retval = uinput_set_bit(arg, sndbit, SND_MAX);
757			goto out;
758
759		case UI_SET_FFBIT:
760			retval = uinput_set_bit(arg, ffbit, FF_MAX);
761			goto out;
762
763		case UI_SET_SWBIT:
764			retval = uinput_set_bit(arg, swbit, SW_MAX);
765			goto out;
766
767		case UI_SET_PROPBIT:
768			retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
769			goto out;
770
771		case UI_SET_PHYS:
772			if (udev->state == UIST_CREATED) {
773				retval = -EINVAL;
774				goto out;
775			}
776
777			phys = strndup_user(p, 1024);
778			if (IS_ERR(phys)) {
779				retval = PTR_ERR(phys);
780				goto out;
781			}
782
783			kfree(udev->dev->phys);
784			udev->dev->phys = phys;
 
 
 
 
 
785			goto out;
 
786
787		case UI_BEGIN_FF_UPLOAD:
788			retval = uinput_ff_upload_from_user(p, &ff_up);
789			if (retval)
790				goto out;
 
791
792			req = uinput_request_find(udev, ff_up.request_id);
793			if (!req || req->code != UI_FF_UPLOAD ||
794			    !req->u.upload.effect) {
795				retval = -EINVAL;
796				goto out;
797			}
798
799			ff_up.retval = 0;
800			ff_up.effect = *req->u.upload.effect;
801			if (req->u.upload.old)
802				ff_up.old = *req->u.upload.old;
803			else
804				memset(&ff_up.old, 0, sizeof(struct ff_effect));
805
806			retval = uinput_ff_upload_to_user(p, &ff_up);
 
 
 
807			goto out;
 
808
809		case UI_BEGIN_FF_ERASE:
810			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
811				retval = -EFAULT;
812				goto out;
813			}
 
814
815			req = uinput_request_find(udev, ff_erase.request_id);
816			if (!req || req->code != UI_FF_ERASE) {
817				retval = -EINVAL;
818				goto out;
819			}
820
821			ff_erase.retval = 0;
822			ff_erase.effect_id = req->u.effect_id;
823			if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
824				retval = -EFAULT;
825				goto out;
826			}
827
 
 
 
828			goto out;
 
829
830		case UI_END_FF_UPLOAD:
831			retval = uinput_ff_upload_from_user(p, &ff_up);
832			if (retval)
833				goto out;
 
 
834
835			req = uinput_request_find(udev, ff_up.request_id);
836			if (!req || req->code != UI_FF_UPLOAD ||
837			    !req->u.upload.effect) {
838				retval = -EINVAL;
839				goto out;
840			}
841
842			req->retval = ff_up.retval;
843			uinput_request_done(udev, req);
 
844			goto out;
845
846		case UI_END_FF_ERASE:
847			if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
848				retval = -EFAULT;
849				goto out;
850			}
 
851
852			req = uinput_request_find(udev, ff_erase.request_id);
853			if (!req || req->code != UI_FF_ERASE) {
854				retval = -EINVAL;
855				goto out;
856			}
857
858			req->retval = ff_erase.retval;
859			uinput_request_done(udev, req);
 
860			goto out;
 
 
 
 
 
 
 
 
 
 
 
861	}
862
863	size = _IOC_SIZE(cmd);
864
865	/* Now check variable-length commands */
866	switch (cmd & ~IOCSIZE_MASK) {
867	case UI_GET_SYSNAME(0):
868		if (udev->state != UIST_CREATED) {
869			retval = -ENOENT;
870			goto out;
871		}
872		name = dev_name(&udev->dev->dev);
873		retval = uinput_str_to_user(p, name, size);
874		goto out;
 
 
 
 
875	}
876
877	retval = -EINVAL;
878 out:
879	mutex_unlock(&udev->mutex);
880	return retval;
881}
882
883static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
884{
885	return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
886}
887
888#ifdef CONFIG_COMPAT
 
 
 
 
 
 
 
 
 
 
 
 
889static long uinput_compat_ioctl(struct file *file,
890				unsigned int cmd, unsigned long arg)
891{
 
 
 
 
 
 
 
 
 
 
 
 
892	return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
893}
894#endif
895
896static const struct file_operations uinput_fops = {
897	.owner		= THIS_MODULE,
898	.open		= uinput_open,
899	.release	= uinput_release,
900	.read		= uinput_read,
901	.write		= uinput_write,
902	.poll		= uinput_poll,
903	.unlocked_ioctl	= uinput_ioctl,
904#ifdef CONFIG_COMPAT
905	.compat_ioctl	= uinput_compat_ioctl,
906#endif
907	.llseek		= no_llseek,
908};
909
910static struct miscdevice uinput_misc = {
911	.fops		= &uinput_fops,
912	.minor		= UINPUT_MINOR,
913	.name		= UINPUT_NAME,
914};
 
 
915MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
916MODULE_ALIAS("devname:" UINPUT_NAME);
917
918static int __init uinput_init(void)
919{
920	return misc_register(&uinput_misc);
921}
922
923static void __exit uinput_exit(void)
924{
925	misc_deregister(&uinput_misc);
926}
927
928MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
929MODULE_DESCRIPTION("User level driver support for input subsystem");
930MODULE_LICENSE("GPL");
931MODULE_VERSION("0.3");
932
933module_init(uinput_init);
934module_exit(uinput_exit);
v5.9
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  User level driver support for input subsystem
   4 *
   5 * Heavily based on evdev.c by Vojtech Pavlik
   6 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   7 * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
   8 *
   9 * Changes/Revisions:
  10 *	0.4	01/09/2014 (Benjamin Tissoires <benjamin.tissoires@redhat.com>)
  11 *		- add UI_GET_SYSNAME ioctl
  12 *	0.3	09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>)
  13 *		- updated ff support for the changes in kernel interface
  14 *		- added MODULE_VERSION
  15 *	0.2	16/10/2004 (Micah Dowty <micah@navi.cx>)
  16 *		- added force feedback support
  17 *              - added UI_SET_PHYS
  18 *	0.1	20/06/2002
  19 *		- first public version
  20 */
  21#include <uapi/linux/uinput.h>
  22#include <linux/poll.h>
  23#include <linux/sched.h>
  24#include <linux/slab.h>
  25#include <linux/module.h>
  26#include <linux/init.h>
  27#include <linux/fs.h>
  28#include <linux/miscdevice.h>
  29#include <linux/overflow.h>
  30#include <linux/input/mt.h>
  31#include "../input-compat.h"
  32
  33#define UINPUT_NAME		"uinput"
  34#define UINPUT_BUFFER_SIZE	16
  35#define UINPUT_NUM_REQUESTS	16
  36
  37enum uinput_state { UIST_NEW_DEVICE, UIST_SETUP_COMPLETE, UIST_CREATED };
  38
  39struct uinput_request {
  40	unsigned int		id;
  41	unsigned int		code;	/* UI_FF_UPLOAD, UI_FF_ERASE */
  42
  43	int			retval;
  44	struct completion	done;
  45
  46	union {
  47		unsigned int	effect_id;
  48		struct {
  49			struct ff_effect *effect;
  50			struct ff_effect *old;
  51		} upload;
  52	} u;
  53};
  54
  55struct uinput_device {
  56	struct input_dev	*dev;
  57	struct mutex		mutex;
  58	enum uinput_state	state;
  59	wait_queue_head_t	waitq;
  60	unsigned char		ready;
  61	unsigned char		head;
  62	unsigned char		tail;
  63	struct input_event	buff[UINPUT_BUFFER_SIZE];
  64	unsigned int		ff_effects_max;
  65
  66	struct uinput_request	*requests[UINPUT_NUM_REQUESTS];
  67	wait_queue_head_t	requests_waitq;
  68	spinlock_t		requests_lock;
  69};
  70
  71static int uinput_dev_event(struct input_dev *dev,
  72			    unsigned int type, unsigned int code, int value)
  73{
  74	struct uinput_device	*udev = input_get_drvdata(dev);
  75	struct timespec64	ts;
  76
  77	ktime_get_ts64(&ts);
  78
  79	udev->buff[udev->head] = (struct input_event) {
  80		.input_event_sec = ts.tv_sec,
  81		.input_event_usec = ts.tv_nsec / NSEC_PER_USEC,
  82		.type = type,
  83		.code = code,
  84		.value = value,
  85	};
  86
 
 
 
 
  87	udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
  88
  89	wake_up_interruptible(&udev->waitq);
  90
  91	return 0;
  92}
  93
  94/* Atomically allocate an ID for the given request. Returns 0 on success. */
  95static bool uinput_request_alloc_id(struct uinput_device *udev,
  96				    struct uinput_request *request)
  97{
  98	unsigned int id;
  99	bool reserved = false;
 100
 101	spin_lock(&udev->requests_lock);
 102
 103	for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
 104		if (!udev->requests[id]) {
 105			request->id = id;
 106			udev->requests[id] = request;
 107			reserved = true;
 108			break;
 109		}
 110	}
 111
 112	spin_unlock(&udev->requests_lock);
 113	return reserved;
 114}
 115
 116static struct uinput_request *uinput_request_find(struct uinput_device *udev,
 117						  unsigned int id)
 118{
 119	/* Find an input request, by ID. Returns NULL if the ID isn't valid. */
 120	if (id >= UINPUT_NUM_REQUESTS)
 121		return NULL;
 122
 123	return udev->requests[id];
 124}
 125
 126static int uinput_request_reserve_slot(struct uinput_device *udev,
 127				       struct uinput_request *request)
 128{
 129	/* Allocate slot. If none are available right away, wait. */
 130	return wait_event_interruptible(udev->requests_waitq,
 131					uinput_request_alloc_id(udev, request));
 132}
 133
 134static void uinput_request_release_slot(struct uinput_device *udev,
 135					unsigned int id)
 136{
 137	/* Mark slot as available */
 138	spin_lock(&udev->requests_lock);
 139	udev->requests[id] = NULL;
 140	spin_unlock(&udev->requests_lock);
 141
 142	wake_up(&udev->requests_waitq);
 143}
 144
 145static int uinput_request_send(struct uinput_device *udev,
 146			       struct uinput_request *request)
 147{
 148	int retval;
 149
 150	retval = mutex_lock_interruptible(&udev->mutex);
 151	if (retval)
 152		return retval;
 153
 154	if (udev->state != UIST_CREATED) {
 155		retval = -ENODEV;
 156		goto out;
 157	}
 158
 159	init_completion(&request->done);
 160
 161	/*
 162	 * Tell our userspace application about this new request
 163	 * by queueing an input event.
 164	 */
 165	uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
 166
 167 out:
 168	mutex_unlock(&udev->mutex);
 169	return retval;
 170}
 171
 172static int uinput_request_submit(struct uinput_device *udev,
 173				 struct uinput_request *request)
 174{
 175	int retval;
 176
 177	retval = uinput_request_reserve_slot(udev, request);
 178	if (retval)
 179		return retval;
 180
 181	retval = uinput_request_send(udev, request);
 182	if (retval)
 183		goto out;
 184
 185	if (!wait_for_completion_timeout(&request->done, 30 * HZ)) {
 186		retval = -ETIMEDOUT;
 187		goto out;
 188	}
 189
 190	retval = request->retval;
 191
 192 out:
 193	uinput_request_release_slot(udev, request->id);
 194	return retval;
 195}
 196
 197/*
 198 * Fail all outstanding requests so handlers don't wait for the userspace
 199 * to finish processing them.
 200 */
 201static void uinput_flush_requests(struct uinput_device *udev)
 202{
 203	struct uinput_request *request;
 204	int i;
 205
 206	spin_lock(&udev->requests_lock);
 207
 208	for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
 209		request = udev->requests[i];
 210		if (request) {
 211			request->retval = -ENODEV;
 212			complete(&request->done);
 213		}
 214	}
 215
 216	spin_unlock(&udev->requests_lock);
 217}
 218
 219static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
 220{
 221	uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
 222}
 223
 224static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
 225{
 226	uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
 227}
 228
 229static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
 230{
 231	return uinput_dev_event(dev, EV_FF, effect_id, value);
 232}
 233
 234static int uinput_dev_upload_effect(struct input_dev *dev,
 235				    struct ff_effect *effect,
 236				    struct ff_effect *old)
 237{
 238	struct uinput_device *udev = input_get_drvdata(dev);
 239	struct uinput_request request;
 240
 241	/*
 242	 * uinput driver does not currently support periodic effects with
 243	 * custom waveform since it does not have a way to pass buffer of
 244	 * samples (custom_data) to userspace. If ever there is a device
 245	 * supporting custom waveforms we would need to define an additional
 246	 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
 247	 */
 248	if (effect->type == FF_PERIODIC &&
 249			effect->u.periodic.waveform == FF_CUSTOM)
 250		return -EINVAL;
 251
 252	request.code = UI_FF_UPLOAD;
 253	request.u.upload.effect = effect;
 254	request.u.upload.old = old;
 255
 256	return uinput_request_submit(udev, &request);
 257}
 258
 259static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
 260{
 261	struct uinput_device *udev = input_get_drvdata(dev);
 262	struct uinput_request request;
 263
 264	if (!test_bit(EV_FF, dev->evbit))
 265		return -ENOSYS;
 266
 267	request.code = UI_FF_ERASE;
 268	request.u.effect_id = effect_id;
 269
 270	return uinput_request_submit(udev, &request);
 271}
 272
 273static int uinput_dev_flush(struct input_dev *dev, struct file *file)
 274{
 275	/*
 276	 * If we are called with file == NULL that means we are tearing
 277	 * down the device, and therefore we can not handle FF erase
 278	 * requests: either we are handling UI_DEV_DESTROY (and holding
 279	 * the udev->mutex), or the file descriptor is closed and there is
 280	 * nobody on the other side anymore.
 281	 */
 282	return file ? input_ff_flush(dev, file) : 0;
 283}
 284
 285static void uinput_destroy_device(struct uinput_device *udev)
 286{
 287	const char *name, *phys;
 288	struct input_dev *dev = udev->dev;
 289	enum uinput_state old_state = udev->state;
 290
 291	udev->state = UIST_NEW_DEVICE;
 292
 293	if (dev) {
 294		name = dev->name;
 295		phys = dev->phys;
 296		if (old_state == UIST_CREATED) {
 297			uinput_flush_requests(udev);
 298			input_unregister_device(dev);
 299		} else {
 300			input_free_device(dev);
 301		}
 302		kfree(name);
 303		kfree(phys);
 304		udev->dev = NULL;
 305	}
 306}
 307
 308static int uinput_create_device(struct uinput_device *udev)
 309{
 310	struct input_dev *dev = udev->dev;
 311	int error, nslot;
 312
 313	if (udev->state != UIST_SETUP_COMPLETE) {
 314		printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
 315		return -EINVAL;
 316	}
 317
 318	if (test_bit(EV_ABS, dev->evbit)) {
 319		input_alloc_absinfo(dev);
 320		if (!dev->absinfo) {
 321			error = -EINVAL;
 322			goto fail1;
 323		}
 324
 325		if (test_bit(ABS_MT_SLOT, dev->absbit)) {
 326			nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
 327			error = input_mt_init_slots(dev, nslot, 0);
 328			if (error)
 329				goto fail1;
 330		} else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
 331			input_set_events_per_packet(dev, 60);
 332		}
 333	}
 334
 335	if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) {
 336		printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n",
 337			UINPUT_NAME);
 338		error = -EINVAL;
 339		goto fail1;
 340	}
 341
 342	if (udev->ff_effects_max) {
 343		error = input_ff_create(dev, udev->ff_effects_max);
 344		if (error)
 345			goto fail1;
 346
 347		dev->ff->upload = uinput_dev_upload_effect;
 348		dev->ff->erase = uinput_dev_erase_effect;
 349		dev->ff->playback = uinput_dev_playback;
 350		dev->ff->set_gain = uinput_dev_set_gain;
 351		dev->ff->set_autocenter = uinput_dev_set_autocenter;
 352		/*
 353		 * The standard input_ff_flush() implementation does
 354		 * not quite work for uinput as we can't reasonably
 355		 * handle FF requests during device teardown.
 356		 */
 357		dev->flush = uinput_dev_flush;
 358	}
 359
 360	dev->event = uinput_dev_event;
 361
 362	input_set_drvdata(udev->dev, udev);
 363
 364	error = input_register_device(udev->dev);
 365	if (error)
 366		goto fail2;
 367
 368	udev->state = UIST_CREATED;
 369
 370	return 0;
 371
 372 fail2:	input_ff_destroy(dev);
 373 fail1: uinput_destroy_device(udev);
 374	return error;
 375}
 376
 377static int uinput_open(struct inode *inode, struct file *file)
 378{
 379	struct uinput_device *newdev;
 380
 381	newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
 382	if (!newdev)
 383		return -ENOMEM;
 384
 385	mutex_init(&newdev->mutex);
 386	spin_lock_init(&newdev->requests_lock);
 387	init_waitqueue_head(&newdev->requests_waitq);
 388	init_waitqueue_head(&newdev->waitq);
 389	newdev->state = UIST_NEW_DEVICE;
 390
 391	file->private_data = newdev;
 392	stream_open(inode, file);
 393
 394	return 0;
 395}
 396
 397static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code,
 398				   const struct input_absinfo *abs)
 399{
 400	int min, max, range;
 401
 402	min = abs->minimum;
 403	max = abs->maximum;
 404
 405	if ((min != 0 || max != 0) && max < min) {
 406		printk(KERN_DEBUG
 407		       "%s: invalid abs[%02x] min:%d max:%d\n",
 408		       UINPUT_NAME, code, min, max);
 409		return -EINVAL;
 410	}
 411
 412	if (!check_sub_overflow(max, min, &range) && abs->flat > range) {
 413		printk(KERN_DEBUG
 414		       "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n",
 415		       UINPUT_NAME, code, abs->flat, min, max);
 416		return -EINVAL;
 417	}
 418
 419	return 0;
 420}
 421
 422static int uinput_validate_absbits(struct input_dev *dev)
 423{
 424	unsigned int cnt;
 425	int error;
 426
 427	if (!test_bit(EV_ABS, dev->evbit))
 428		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 429
 430	/*
 431	 * Check if absmin/absmax/absfuzz/absflat are sane.
 432	 */
 433
 434	for_each_set_bit(cnt, dev->absbit, ABS_CNT) {
 435		if (!dev->absinfo)
 436			return -EINVAL;
 437
 438		error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]);
 439		if (error)
 440			return error;
 
 441	}
 442
 443	return 0;
 444}
 445
 446static int uinput_dev_setup(struct uinput_device *udev,
 447			    struct uinput_setup __user *arg)
 448{
 449	struct uinput_setup setup;
 450	struct input_dev *dev;
 451
 452	if (udev->state == UIST_CREATED)
 453		return -EINVAL;
 454
 455	if (copy_from_user(&setup, arg, sizeof(setup)))
 456		return -EFAULT;
 457
 458	if (!setup.name[0])
 459		return -EINVAL;
 460
 461	dev = udev->dev;
 462	dev->id = setup.id;
 463	udev->ff_effects_max = setup.ff_effects_max;
 464
 465	kfree(dev->name);
 466	dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL);
 467	if (!dev->name)
 468		return -ENOMEM;
 469
 470	udev->state = UIST_SETUP_COMPLETE;
 471	return 0;
 472}
 473
 474static int uinput_abs_setup(struct uinput_device *udev,
 475			    struct uinput_setup __user *arg, size_t size)
 476{
 477	struct uinput_abs_setup setup = {};
 478	struct input_dev *dev;
 479	int error;
 480
 481	if (size > sizeof(setup))
 482		return -E2BIG;
 483
 484	if (udev->state == UIST_CREATED)
 485		return -EINVAL;
 486
 487	if (copy_from_user(&setup, arg, size))
 488		return -EFAULT;
 489
 490	if (setup.code > ABS_MAX)
 491		return -ERANGE;
 492
 493	dev = udev->dev;
 494
 495	error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo);
 496	if (error)
 497		return error;
 498
 499	input_alloc_absinfo(dev);
 500	if (!dev->absinfo)
 501		return -ENOMEM;
 502
 503	set_bit(setup.code, dev->absbit);
 504	dev->absinfo[setup.code] = setup.absinfo;
 505	return 0;
 506}
 507
 508/* legacy setup via write() */
 509static int uinput_setup_device_legacy(struct uinput_device *udev,
 510				      const char __user *buffer, size_t count)
 511{
 512	struct uinput_user_dev	*user_dev;
 513	struct input_dev	*dev;
 514	int			i;
 515	int			retval;
 516
 517	if (count != sizeof(struct uinput_user_dev))
 518		return -EINVAL;
 519
 520	if (!udev->dev) {
 521		udev->dev = input_allocate_device();
 522		if (!udev->dev)
 523			return -ENOMEM;
 524	}
 525
 526	dev = udev->dev;
 527
 528	user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
 529	if (IS_ERR(user_dev))
 530		return PTR_ERR(user_dev);
 531
 532	udev->ff_effects_max = user_dev->ff_effects_max;
 533
 534	/* Ensure name is filled in */
 535	if (!user_dev->name[0]) {
 536		retval = -EINVAL;
 537		goto exit;
 538	}
 539
 540	kfree(dev->name);
 541	dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
 542			     GFP_KERNEL);
 543	if (!dev->name) {
 544		retval = -ENOMEM;
 545		goto exit;
 546	}
 547
 548	dev->id.bustype	= user_dev->id.bustype;
 549	dev->id.vendor	= user_dev->id.vendor;
 550	dev->id.product	= user_dev->id.product;
 551	dev->id.version	= user_dev->id.version;
 552
 553	for (i = 0; i < ABS_CNT; i++) {
 554		input_abs_set_max(dev, i, user_dev->absmax[i]);
 555		input_abs_set_min(dev, i, user_dev->absmin[i]);
 556		input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
 557		input_abs_set_flat(dev, i, user_dev->absflat[i]);
 558	}
 559
 560	retval = uinput_validate_absbits(dev);
 561	if (retval < 0)
 562		goto exit;
 
 
 
 
 
 
 
 
 
 
 563
 564	udev->state = UIST_SETUP_COMPLETE;
 565	retval = count;
 566
 567 exit:
 568	kfree(user_dev);
 569	return retval;
 570}
 571
 572static ssize_t uinput_inject_events(struct uinput_device *udev,
 573				    const char __user *buffer, size_t count)
 574{
 575	struct input_event ev;
 576	size_t bytes = 0;
 577
 578	if (count != 0 && count < input_event_size())
 579		return -EINVAL;
 580
 581	while (bytes + input_event_size() <= count) {
 582		/*
 583		 * Note that even if some events were fetched successfully
 584		 * we are still going to return EFAULT instead of partial
 585		 * count to let userspace know that it got it's buffers
 586		 * all wrong.
 587		 */
 588		if (input_event_from_user(buffer + bytes, &ev))
 589			return -EFAULT;
 590
 591		input_event(udev->dev, ev.type, ev.code, ev.value);
 592		bytes += input_event_size();
 593		cond_resched();
 594	}
 595
 596	return bytes;
 597}
 598
 599static ssize_t uinput_write(struct file *file, const char __user *buffer,
 600			    size_t count, loff_t *ppos)
 601{
 602	struct uinput_device *udev = file->private_data;
 603	int retval;
 604
 605	if (count == 0)
 606		return 0;
 607
 608	retval = mutex_lock_interruptible(&udev->mutex);
 609	if (retval)
 610		return retval;
 611
 612	retval = udev->state == UIST_CREATED ?
 613			uinput_inject_events(udev, buffer, count) :
 614			uinput_setup_device_legacy(udev, buffer, count);
 615
 616	mutex_unlock(&udev->mutex);
 617
 618	return retval;
 619}
 620
 621static bool uinput_fetch_next_event(struct uinput_device *udev,
 622				    struct input_event *event)
 623{
 624	bool have_event;
 625
 626	spin_lock_irq(&udev->dev->event_lock);
 627
 628	have_event = udev->head != udev->tail;
 629	if (have_event) {
 630		*event = udev->buff[udev->tail];
 631		udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
 632	}
 633
 634	spin_unlock_irq(&udev->dev->event_lock);
 635
 636	return have_event;
 637}
 638
 639static ssize_t uinput_events_to_user(struct uinput_device *udev,
 640				     char __user *buffer, size_t count)
 641{
 642	struct input_event event;
 643	size_t read = 0;
 644
 645	while (read + input_event_size() <= count &&
 646	       uinput_fetch_next_event(udev, &event)) {
 647
 648		if (input_event_to_user(buffer + read, &event))
 649			return -EFAULT;
 650
 651		read += input_event_size();
 652	}
 653
 654	return read;
 655}
 656
 657static ssize_t uinput_read(struct file *file, char __user *buffer,
 658			   size_t count, loff_t *ppos)
 659{
 660	struct uinput_device *udev = file->private_data;
 661	ssize_t retval;
 662
 663	if (count != 0 && count < input_event_size())
 664		return -EINVAL;
 665
 666	do {
 667		retval = mutex_lock_interruptible(&udev->mutex);
 668		if (retval)
 669			return retval;
 670
 671		if (udev->state != UIST_CREATED)
 672			retval = -ENODEV;
 673		else if (udev->head == udev->tail &&
 674			 (file->f_flags & O_NONBLOCK))
 675			retval = -EAGAIN;
 676		else
 677			retval = uinput_events_to_user(udev, buffer, count);
 678
 679		mutex_unlock(&udev->mutex);
 680
 681		if (retval || count == 0)
 682			break;
 683
 684		if (!(file->f_flags & O_NONBLOCK))
 685			retval = wait_event_interruptible(udev->waitq,
 686						  udev->head != udev->tail ||
 687						  udev->state != UIST_CREATED);
 688	} while (retval == 0);
 689
 690	return retval;
 691}
 692
 693static __poll_t uinput_poll(struct file *file, poll_table *wait)
 694{
 695	struct uinput_device *udev = file->private_data;
 696	__poll_t mask = EPOLLOUT | EPOLLWRNORM; /* uinput is always writable */
 697
 698	poll_wait(file, &udev->waitq, wait);
 699
 700	if (udev->head != udev->tail)
 701		mask |= EPOLLIN | EPOLLRDNORM;
 702
 703	return mask;
 704}
 705
 706static int uinput_release(struct inode *inode, struct file *file)
 707{
 708	struct uinput_device *udev = file->private_data;
 709
 710	uinput_destroy_device(udev);
 711	kfree(udev);
 712
 713	return 0;
 714}
 715
 716#ifdef CONFIG_COMPAT
 717struct uinput_ff_upload_compat {
 718	__u32			request_id;
 719	__s32			retval;
 720	struct ff_effect_compat	effect;
 721	struct ff_effect_compat	old;
 722};
 723
 724static int uinput_ff_upload_to_user(char __user *buffer,
 725				    const struct uinput_ff_upload *ff_up)
 726{
 727	if (in_compat_syscall()) {
 728		struct uinput_ff_upload_compat ff_up_compat;
 729
 730		ff_up_compat.request_id = ff_up->request_id;
 731		ff_up_compat.retval = ff_up->retval;
 732		/*
 733		 * It so happens that the pointer that gives us the trouble
 734		 * is the last field in the structure. Since we don't support
 735		 * custom waveforms in uinput anyway we can just copy the whole
 736		 * thing (to the compat size) and ignore the pointer.
 737		 */
 738		memcpy(&ff_up_compat.effect, &ff_up->effect,
 739			sizeof(struct ff_effect_compat));
 740		memcpy(&ff_up_compat.old, &ff_up->old,
 741			sizeof(struct ff_effect_compat));
 742
 743		if (copy_to_user(buffer, &ff_up_compat,
 744				 sizeof(struct uinput_ff_upload_compat)))
 745			return -EFAULT;
 746	} else {
 747		if (copy_to_user(buffer, ff_up,
 748				 sizeof(struct uinput_ff_upload)))
 749			return -EFAULT;
 750	}
 751
 752	return 0;
 753}
 754
 755static int uinput_ff_upload_from_user(const char __user *buffer,
 756				      struct uinput_ff_upload *ff_up)
 757{
 758	if (in_compat_syscall()) {
 759		struct uinput_ff_upload_compat ff_up_compat;
 760
 761		if (copy_from_user(&ff_up_compat, buffer,
 762				   sizeof(struct uinput_ff_upload_compat)))
 763			return -EFAULT;
 764
 765		ff_up->request_id = ff_up_compat.request_id;
 766		ff_up->retval = ff_up_compat.retval;
 767		memcpy(&ff_up->effect, &ff_up_compat.effect,
 768			sizeof(struct ff_effect_compat));
 769		memcpy(&ff_up->old, &ff_up_compat.old,
 770			sizeof(struct ff_effect_compat));
 771
 772	} else {
 773		if (copy_from_user(ff_up, buffer,
 774				   sizeof(struct uinput_ff_upload)))
 775			return -EFAULT;
 776	}
 777
 778	return 0;
 779}
 780
 781#else
 782
 783static int uinput_ff_upload_to_user(char __user *buffer,
 784				    const struct uinput_ff_upload *ff_up)
 785{
 786	if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
 787		return -EFAULT;
 788
 789	return 0;
 790}
 791
 792static int uinput_ff_upload_from_user(const char __user *buffer,
 793				      struct uinput_ff_upload *ff_up)
 794{
 795	if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
 796		return -EFAULT;
 797
 798	return 0;
 799}
 800
 801#endif
 802
 803#define uinput_set_bit(_arg, _bit, _max)		\
 804({							\
 805	int __ret = 0;					\
 806	if (udev->state == UIST_CREATED)		\
 807		__ret =  -EINVAL;			\
 808	else if ((_arg) > (_max))			\
 809		__ret = -EINVAL;			\
 810	else set_bit((_arg), udev->dev->_bit);		\
 811	__ret;						\
 812})
 813
 814static int uinput_str_to_user(void __user *dest, const char *str,
 815			      unsigned int maxlen)
 816{
 817	char __user *p = dest;
 818	int len, ret;
 819
 820	if (!str)
 821		return -ENOENT;
 822
 823	if (maxlen == 0)
 824		return -EINVAL;
 825
 826	len = strlen(str) + 1;
 827	if (len > maxlen)
 828		len = maxlen;
 829
 830	ret = copy_to_user(p, str, len);
 831	if (ret)
 832		return -EFAULT;
 833
 834	/* force terminating '\0' */
 835	ret = put_user(0, p + len - 1);
 836	return ret ? -EFAULT : len;
 837}
 838
 839static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
 840				 unsigned long arg, void __user *p)
 841{
 842	int			retval;
 843	struct uinput_device	*udev = file->private_data;
 844	struct uinput_ff_upload ff_up;
 845	struct uinput_ff_erase  ff_erase;
 846	struct uinput_request   *req;
 847	char			*phys;
 848	const char		*name;
 849	unsigned int		size;
 850
 851	retval = mutex_lock_interruptible(&udev->mutex);
 852	if (retval)
 853		return retval;
 854
 855	if (!udev->dev) {
 856		udev->dev = input_allocate_device();
 857		if (!udev->dev) {
 858			retval = -ENOMEM;
 859			goto out;
 860		}
 861	}
 862
 863	switch (cmd) {
 864	case UI_GET_VERSION:
 865		if (put_user(UINPUT_VERSION, (unsigned int __user *)p))
 866			retval = -EFAULT;
 867		goto out;
 868
 869	case UI_DEV_CREATE:
 870		retval = uinput_create_device(udev);
 871		goto out;
 872
 873	case UI_DEV_DESTROY:
 874		uinput_destroy_device(udev);
 875		goto out;
 876
 877	case UI_DEV_SETUP:
 878		retval = uinput_dev_setup(udev, p);
 879		goto out;
 880
 881	/* UI_ABS_SETUP is handled in the variable size ioctls */
 
 
 882
 883	case UI_SET_EVBIT:
 884		retval = uinput_set_bit(arg, evbit, EV_MAX);
 885		goto out;
 886
 887	case UI_SET_KEYBIT:
 888		retval = uinput_set_bit(arg, keybit, KEY_MAX);
 889		goto out;
 890
 891	case UI_SET_RELBIT:
 892		retval = uinput_set_bit(arg, relbit, REL_MAX);
 893		goto out;
 894
 895	case UI_SET_ABSBIT:
 896		retval = uinput_set_bit(arg, absbit, ABS_MAX);
 897		goto out;
 898
 899	case UI_SET_MSCBIT:
 900		retval = uinput_set_bit(arg, mscbit, MSC_MAX);
 901		goto out;
 902
 903	case UI_SET_LEDBIT:
 904		retval = uinput_set_bit(arg, ledbit, LED_MAX);
 905		goto out;
 906
 907	case UI_SET_SNDBIT:
 908		retval = uinput_set_bit(arg, sndbit, SND_MAX);
 909		goto out;
 910
 911	case UI_SET_FFBIT:
 912		retval = uinput_set_bit(arg, ffbit, FF_MAX);
 913		goto out;
 
 
 914
 915	case UI_SET_SWBIT:
 916		retval = uinput_set_bit(arg, swbit, SW_MAX);
 917		goto out;
 
 
 918
 919	case UI_SET_PROPBIT:
 920		retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
 921		goto out;
 922
 923	case UI_SET_PHYS:
 924		if (udev->state == UIST_CREATED) {
 925			retval = -EINVAL;
 926			goto out;
 927		}
 928
 929		phys = strndup_user(p, 1024);
 930		if (IS_ERR(phys)) {
 931			retval = PTR_ERR(phys);
 932			goto out;
 933		}
 934
 935		kfree(udev->dev->phys);
 936		udev->dev->phys = phys;
 937		goto out;
 
 
 
 938
 939	case UI_BEGIN_FF_UPLOAD:
 940		retval = uinput_ff_upload_from_user(p, &ff_up);
 941		if (retval)
 942			goto out;
 
 
 943
 944		req = uinput_request_find(udev, ff_up.request_id);
 945		if (!req || req->code != UI_FF_UPLOAD ||
 946		    !req->u.upload.effect) {
 947			retval = -EINVAL;
 948			goto out;
 949		}
 950
 951		ff_up.retval = 0;
 952		ff_up.effect = *req->u.upload.effect;
 953		if (req->u.upload.old)
 954			ff_up.old = *req->u.upload.old;
 955		else
 956			memset(&ff_up.old, 0, sizeof(struct ff_effect));
 957
 958		retval = uinput_ff_upload_to_user(p, &ff_up);
 959		goto out;
 
 
 
 960
 961	case UI_BEGIN_FF_ERASE:
 962		if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
 963			retval = -EFAULT;
 964			goto out;
 965		}
 
 966
 967		req = uinput_request_find(udev, ff_erase.request_id);
 968		if (!req || req->code != UI_FF_ERASE) {
 969			retval = -EINVAL;
 970			goto out;
 971		}
 972
 973		ff_erase.retval = 0;
 974		ff_erase.effect_id = req->u.effect_id;
 975		if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
 976			retval = -EFAULT;
 977			goto out;
 978		}
 979
 980		goto out;
 
 
 
 
 
 981
 982	case UI_END_FF_UPLOAD:
 983		retval = uinput_ff_upload_from_user(p, &ff_up);
 984		if (retval)
 985			goto out;
 986
 987		req = uinput_request_find(udev, ff_up.request_id);
 988		if (!req || req->code != UI_FF_UPLOAD ||
 989		    !req->u.upload.effect) {
 990			retval = -EINVAL;
 991			goto out;
 992		}
 993
 994		req->retval = ff_up.retval;
 995		complete(&req->done);
 996		goto out;
 
 
 997
 998	case UI_END_FF_ERASE:
 999		if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
1000			retval = -EFAULT;
1001			goto out;
1002		}
1003
1004		req = uinput_request_find(udev, ff_erase.request_id);
1005		if (!req || req->code != UI_FF_ERASE) {
1006			retval = -EINVAL;
1007			goto out;
1008		}
1009
1010		req->retval = ff_erase.retval;
1011		complete(&req->done);
1012		goto out;
1013	}
1014
1015	size = _IOC_SIZE(cmd);
1016
1017	/* Now check variable-length commands */
1018	switch (cmd & ~IOCSIZE_MASK) {
1019	case UI_GET_SYSNAME(0):
1020		if (udev->state != UIST_CREATED) {
1021			retval = -ENOENT;
1022			goto out;
1023		}
1024		name = dev_name(&udev->dev->dev);
1025		retval = uinput_str_to_user(p, name, size);
1026		goto out;
1027
1028	case UI_ABS_SETUP & ~IOCSIZE_MASK:
1029		retval = uinput_abs_setup(udev, p, size);
1030		goto out;
1031	}
1032
1033	retval = -EINVAL;
1034 out:
1035	mutex_unlock(&udev->mutex);
1036	return retval;
1037}
1038
1039static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1040{
1041	return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
1042}
1043
1044#ifdef CONFIG_COMPAT
1045
1046/*
1047 * These IOCTLs change their size and thus their numbers between
1048 * 32 and 64 bits.
1049 */
1050#define UI_SET_PHYS_COMPAT		\
1051	_IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t)
1052#define UI_BEGIN_FF_UPLOAD_COMPAT	\
1053	_IOWR(UINPUT_IOCTL_BASE, 200, struct uinput_ff_upload_compat)
1054#define UI_END_FF_UPLOAD_COMPAT		\
1055	_IOW(UINPUT_IOCTL_BASE, 201, struct uinput_ff_upload_compat)
1056
1057static long uinput_compat_ioctl(struct file *file,
1058				unsigned int cmd, unsigned long arg)
1059{
1060	switch (cmd) {
1061	case UI_SET_PHYS_COMPAT:
1062		cmd = UI_SET_PHYS;
1063		break;
1064	case UI_BEGIN_FF_UPLOAD_COMPAT:
1065		cmd = UI_BEGIN_FF_UPLOAD;
1066		break;
1067	case UI_END_FF_UPLOAD_COMPAT:
1068		cmd = UI_END_FF_UPLOAD;
1069		break;
1070	}
1071
1072	return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
1073}
1074#endif
1075
1076static const struct file_operations uinput_fops = {
1077	.owner		= THIS_MODULE,
1078	.open		= uinput_open,
1079	.release	= uinput_release,
1080	.read		= uinput_read,
1081	.write		= uinput_write,
1082	.poll		= uinput_poll,
1083	.unlocked_ioctl	= uinput_ioctl,
1084#ifdef CONFIG_COMPAT
1085	.compat_ioctl	= uinput_compat_ioctl,
1086#endif
1087	.llseek		= no_llseek,
1088};
1089
1090static struct miscdevice uinput_misc = {
1091	.fops		= &uinput_fops,
1092	.minor		= UINPUT_MINOR,
1093	.name		= UINPUT_NAME,
1094};
1095module_misc_device(uinput_misc);
1096
1097MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
1098MODULE_ALIAS("devname:" UINPUT_NAME);
1099
 
 
 
 
 
 
 
 
 
 
1100MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
1101MODULE_DESCRIPTION("User level driver support for input subsystem");
1102MODULE_LICENSE("GPL");