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