projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Merge branch 'for-3.18/drivers' of git://git.kernel.dk/linux-block
[deliverable/linux.git] / drivers / staging / comedi / comedi_fops.c
1 /*
2 comedi/comedi_fops.c
3 comedi kernel module
4
5 COMEDI - Linux Control and Measurement Device Interface
6 Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org>
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17 */
18
19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20
21 #include "comedi_compat32.h"
22
23 #include <linux/module.h>
24 #include <linux/errno.h>
25 #include <linux/kernel.h>
26 #include <linux/sched.h>
27 #include <linux/fcntl.h>
28 #include <linux/delay.h>
29 #include <linux/mm.h>
30 #include <linux/slab.h>
31 #include <linux/kmod.h>
32 #include <linux/poll.h>
33 #include <linux/init.h>
34 #include <linux/device.h>
35 #include <linux/vmalloc.h>
36 #include <linux/fs.h>
37 #include "comedidev.h"
38 #include <linux/cdev.h>
39 #include <linux/stat.h>
40
41 #include <linux/io.h>
42 #include <linux/uaccess.h>
43
44 #include "comedi_internal.h"
45
46 #define COMEDI_NUM_MINORS 0x100
47 #define COMEDI_NUM_SUBDEVICE_MINORS \
48 (COMEDI_NUM_MINORS - COMEDI_NUM_BOARD_MINORS)
49
50 static int comedi_num_legacy_minors;
51 module_param(comedi_num_legacy_minors, int, S_IRUGO);
52 MODULE_PARM_DESC(comedi_num_legacy_minors,
53 "number of comedi minor devices to reserve for non-auto-configured devices (default 0)"
54 );
55
56 unsigned int comedi_default_buf_size_kb = CONFIG_COMEDI_DEFAULT_BUF_SIZE_KB;
57 module_param(comedi_default_buf_size_kb, uint, S_IRUGO | S_IWUSR);
58 MODULE_PARM_DESC(comedi_default_buf_size_kb,
59 "default asynchronous buffer size in KiB (default "
60 __MODULE_STRING(CONFIG_COMEDI_DEFAULT_BUF_SIZE_KB) ")");
61
62 unsigned int comedi_default_buf_maxsize_kb
63 = CONFIG_COMEDI_DEFAULT_BUF_MAXSIZE_KB;
64 module_param(comedi_default_buf_maxsize_kb, uint, S_IRUGO | S_IWUSR);
65 MODULE_PARM_DESC(comedi_default_buf_maxsize_kb,
66 "default maximum size of asynchronous buffer in KiB (default "
67 __MODULE_STRING(CONFIG_COMEDI_DEFAULT_BUF_MAXSIZE_KB) ")");
68
69 static DEFINE_MUTEX(comedi_board_minor_table_lock);
70 static struct comedi_device
71 *comedi_board_minor_table[COMEDI_NUM_BOARD_MINORS];
72
73 static DEFINE_MUTEX(comedi_subdevice_minor_table_lock);
74 /* Note: indexed by minor - COMEDI_NUM_BOARD_MINORS. */
75 static struct comedi_subdevice
76 *comedi_subdevice_minor_table[COMEDI_NUM_SUBDEVICE_MINORS];
77
78 static struct class *comedi_class;
79 static struct cdev comedi_cdev;
80
81 static void comedi_device_init(struct comedi_device *dev)
82 {
83 kref_init(&dev->refcount);
84 spin_lock_init(&dev->spinlock);
85 mutex_init(&dev->mutex);
86 init_rwsem(&dev->attach_lock);
87 dev->minor = -1;
88 }
89
90 static void comedi_dev_kref_release(struct kref *kref)
91 {
92 struct comedi_device *dev =
93 container_of(kref, struct comedi_device, refcount);
94
95 mutex_destroy(&dev->mutex);
96 put_device(dev->class_dev);
97 kfree(dev);
98 }
99
100 int comedi_dev_put(struct comedi_device *dev)
101 {
102 if (dev)
103 return kref_put(&dev->refcount, comedi_dev_kref_release);
104 return 1;
105 }
106 EXPORT_SYMBOL_GPL(comedi_dev_put);
107
108 static struct comedi_device *comedi_dev_get(struct comedi_device *dev)
109 {
110 if (dev)
111 kref_get(&dev->refcount);
112 return dev;
113 }
114
115 static void comedi_device_cleanup(struct comedi_device *dev)
116 {
117 struct module *driver_module = NULL;
118
119 if (dev == NULL)
120 return;
121 mutex_lock(&dev->mutex);
122 if (dev->attached)
123 driver_module = dev->driver->module;
124 comedi_device_detach(dev);
125 if (driver_module && dev->use_count)
126 module_put(driver_module);
127 mutex_unlock(&dev->mutex);
128 }
129
130 static bool comedi_clear_board_dev(struct comedi_device *dev)
131 {
132 unsigned int i = dev->minor;
133 bool cleared = false;
134
135 mutex_lock(&comedi_board_minor_table_lock);
136 if (dev == comedi_board_minor_table[i]) {
137 comedi_board_minor_table[i] = NULL;
138 cleared = true;
139 }
140 mutex_unlock(&comedi_board_minor_table_lock);
141 return cleared;
142 }
143
144 static struct comedi_device *comedi_clear_board_minor(unsigned minor)
145 {
146 struct comedi_device *dev;
147
148 mutex_lock(&comedi_board_minor_table_lock);
149 dev = comedi_board_minor_table[minor];
150 comedi_board_minor_table[minor] = NULL;
151 mutex_unlock(&comedi_board_minor_table_lock);
152 return dev;
153 }
154
155 static void comedi_free_board_dev(struct comedi_device *dev)
156 {
157 if (dev) {
158 comedi_device_cleanup(dev);
159 if (dev->class_dev) {
160 device_destroy(comedi_class,
161 MKDEV(COMEDI_MAJOR, dev->minor));
162 }
163 comedi_dev_put(dev);
164 }
165 }
166
167 static struct comedi_subdevice
168 *comedi_subdevice_from_minor(const struct comedi_device *dev, unsigned minor)
169 {
170 struct comedi_subdevice *s;
171 unsigned int i = minor - COMEDI_NUM_BOARD_MINORS;
172
173 BUG_ON(i >= COMEDI_NUM_SUBDEVICE_MINORS);
174 mutex_lock(&comedi_subdevice_minor_table_lock);
175 s = comedi_subdevice_minor_table[i];
176 if (s && s->device != dev)
177 s = NULL;
178 mutex_unlock(&comedi_subdevice_minor_table_lock);
179 return s;
180 }
181
182 static struct comedi_device *comedi_dev_get_from_board_minor(unsigned minor)
183 {
184 struct comedi_device *dev;
185
186 BUG_ON(minor >= COMEDI_NUM_BOARD_MINORS);
187 mutex_lock(&comedi_board_minor_table_lock);
188 dev = comedi_dev_get(comedi_board_minor_table[minor]);
189 mutex_unlock(&comedi_board_minor_table_lock);
190 return dev;
191 }
192
193 static struct comedi_device *comedi_dev_get_from_subdevice_minor(unsigned minor)
194 {
195 struct comedi_device *dev;
196 struct comedi_subdevice *s;
197 unsigned int i = minor - COMEDI_NUM_BOARD_MINORS;
198
199 BUG_ON(i >= COMEDI_NUM_SUBDEVICE_MINORS);
200 mutex_lock(&comedi_subdevice_minor_table_lock);
201 s = comedi_subdevice_minor_table[i];
202 dev = comedi_dev_get(s ? s->device : NULL);
203 mutex_unlock(&comedi_subdevice_minor_table_lock);
204 return dev;
205 }
206
207 struct comedi_device *comedi_dev_get_from_minor(unsigned minor)
208 {
209 if (minor < COMEDI_NUM_BOARD_MINORS)
210 return comedi_dev_get_from_board_minor(minor);
211
212 return comedi_dev_get_from_subdevice_minor(minor);
213 }
214 EXPORT_SYMBOL_GPL(comedi_dev_get_from_minor);
215
216 static struct comedi_subdevice *
217 comedi_read_subdevice(const struct comedi_device *dev, unsigned int minor)
218 {
219 struct comedi_subdevice *s;
220
221 if (minor >= COMEDI_NUM_BOARD_MINORS) {
222 s = comedi_subdevice_from_minor(dev, minor);
223 if (s == NULL || (s->subdev_flags & SDF_CMD_READ))
224 return s;
225 }
226 return dev->read_subdev;
227 }
228
229 static struct comedi_subdevice *
230 comedi_write_subdevice(const struct comedi_device *dev, unsigned int minor)
231 {
232 struct comedi_subdevice *s;
233
234 if (minor >= COMEDI_NUM_BOARD_MINORS) {
235 s = comedi_subdevice_from_minor(dev, minor);
236 if (s == NULL || (s->subdev_flags & SDF_CMD_WRITE))
237 return s;
238 }
239 return dev->write_subdev;
240 }
241
242 static int resize_async_buffer(struct comedi_device *dev,
243 struct comedi_subdevice *s, unsigned new_size)
244 {
245 struct comedi_async *async = s->async;
246 int retval;
247
248 if (new_size > async->max_bufsize)
249 return -EPERM;
250
251 if (s->busy) {
252 dev_dbg(dev->class_dev,
253 "subdevice is busy, cannot resize buffer\n");
254 return -EBUSY;
255 }
256 if (comedi_buf_is_mmapped(s)) {
257 dev_dbg(dev->class_dev,
258 "subdevice is mmapped, cannot resize buffer\n");
259 return -EBUSY;
260 }
261
262 /* make sure buffer is an integral number of pages
263 * (we round up) */
264 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK;
265
266 retval = comedi_buf_alloc(dev, s, new_size);
267 if (retval < 0)
268 return retval;
269
270 if (s->buf_change) {
271 retval = s->buf_change(dev, s);
272 if (retval < 0)
273 return retval;
274 }
275
276 dev_dbg(dev->class_dev, "subd %d buffer resized to %i bytes\n",
277 s->index, async->prealloc_bufsz);
278 return 0;
279 }
280
281 /* sysfs attribute files */
282
283 static ssize_t max_read_buffer_kb_show(struct device *csdev,
284 struct device_attribute *attr, char *buf)
285 {
286 unsigned int minor = MINOR(csdev->devt);
287 struct comedi_device *dev;
288 struct comedi_subdevice *s;
289 unsigned int size = 0;
290
291 dev = comedi_dev_get_from_minor(minor);
292 if (!dev)
293 return -ENODEV;
294
295 mutex_lock(&dev->mutex);
296 s = comedi_read_subdevice(dev, minor);
297 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
298 size = s->async->max_bufsize / 1024;
299 mutex_unlock(&dev->mutex);
300
301 comedi_dev_put(dev);
302 return snprintf(buf, PAGE_SIZE, "%u\n", size);
303 }
304
305 static ssize_t max_read_buffer_kb_store(struct device *csdev,
306 struct device_attribute *attr,
307 const char *buf, size_t count)
308 {
309 unsigned int minor = MINOR(csdev->devt);
310 struct comedi_device *dev;
311 struct comedi_subdevice *s;
312 unsigned int size;
313 int err;
314
315 err = kstrtouint(buf, 10, &size);
316 if (err)
317 return err;
318 if (size > (UINT_MAX / 1024))
319 return -EINVAL;
320 size *= 1024;
321
322 dev = comedi_dev_get_from_minor(minor);
323 if (!dev)
324 return -ENODEV;
325
326 mutex_lock(&dev->mutex);
327 s = comedi_read_subdevice(dev, minor);
328 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
329 s->async->max_bufsize = size;
330 else
331 err = -EINVAL;
332 mutex_unlock(&dev->mutex);
333
334 comedi_dev_put(dev);
335 return err ? err : count;
336 }
337 static DEVICE_ATTR_RW(max_read_buffer_kb);
338
339 static ssize_t read_buffer_kb_show(struct device *csdev,
340 struct device_attribute *attr, char *buf)
341 {
342 unsigned int minor = MINOR(csdev->devt);
343 struct comedi_device *dev;
344 struct comedi_subdevice *s;
345 unsigned int size = 0;
346
347 dev = comedi_dev_get_from_minor(minor);
348 if (!dev)
349 return -ENODEV;
350
351 mutex_lock(&dev->mutex);
352 s = comedi_read_subdevice(dev, minor);
353 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
354 size = s->async->prealloc_bufsz / 1024;
355 mutex_unlock(&dev->mutex);
356
357 comedi_dev_put(dev);
358 return snprintf(buf, PAGE_SIZE, "%u\n", size);
359 }
360
361 static ssize_t read_buffer_kb_store(struct device *csdev,
362 struct device_attribute *attr,
363 const char *buf, size_t count)
364 {
365 unsigned int minor = MINOR(csdev->devt);
366 struct comedi_device *dev;
367 struct comedi_subdevice *s;
368 unsigned int size;
369 int err;
370
371 err = kstrtouint(buf, 10, &size);
372 if (err)
373 return err;
374 if (size > (UINT_MAX / 1024))
375 return -EINVAL;
376 size *= 1024;
377
378 dev = comedi_dev_get_from_minor(minor);
379 if (!dev)
380 return -ENODEV;
381
382 mutex_lock(&dev->mutex);
383 s = comedi_read_subdevice(dev, minor);
384 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
385 err = resize_async_buffer(dev, s, size);
386 else
387 err = -EINVAL;
388 mutex_unlock(&dev->mutex);
389
390 comedi_dev_put(dev);
391 return err ? err : count;
392 }
393 static DEVICE_ATTR_RW(read_buffer_kb);
394
395 static ssize_t max_write_buffer_kb_show(struct device *csdev,
396 struct device_attribute *attr,
397 char *buf)
398 {
399 unsigned int minor = MINOR(csdev->devt);
400 struct comedi_device *dev;
401 struct comedi_subdevice *s;
402 unsigned int size = 0;
403
404 dev = comedi_dev_get_from_minor(minor);
405 if (!dev)
406 return -ENODEV;
407
408 mutex_lock(&dev->mutex);
409 s = comedi_write_subdevice(dev, minor);
410 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
411 size = s->async->max_bufsize / 1024;
412 mutex_unlock(&dev->mutex);
413
414 comedi_dev_put(dev);
415 return snprintf(buf, PAGE_SIZE, "%u\n", size);
416 }
417
418 static ssize_t max_write_buffer_kb_store(struct device *csdev,
419 struct device_attribute *attr,
420 const char *buf, size_t count)
421 {
422 unsigned int minor = MINOR(csdev->devt);
423 struct comedi_device *dev;
424 struct comedi_subdevice *s;
425 unsigned int size;
426 int err;
427
428 err = kstrtouint(buf, 10, &size);
429 if (err)
430 return err;
431 if (size > (UINT_MAX / 1024))
432 return -EINVAL;
433 size *= 1024;
434
435 dev = comedi_dev_get_from_minor(minor);
436 if (!dev)
437 return -ENODEV;
438
439 mutex_lock(&dev->mutex);
440 s = comedi_write_subdevice(dev, minor);
441 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
442 s->async->max_bufsize = size;
443 else
444 err = -EINVAL;
445 mutex_unlock(&dev->mutex);
446
447 comedi_dev_put(dev);
448 return err ? err : count;
449 }
450 static DEVICE_ATTR_RW(max_write_buffer_kb);
451
452 static ssize_t write_buffer_kb_show(struct device *csdev,
453 struct device_attribute *attr, char *buf)
454 {
455 unsigned int minor = MINOR(csdev->devt);
456 struct comedi_device *dev;
457 struct comedi_subdevice *s;
458 unsigned int size = 0;
459
460 dev = comedi_dev_get_from_minor(minor);
461 if (!dev)
462 return -ENODEV;
463
464 mutex_lock(&dev->mutex);
465 s = comedi_write_subdevice(dev, minor);
466 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
467 size = s->async->prealloc_bufsz / 1024;
468 mutex_unlock(&dev->mutex);
469
470 comedi_dev_put(dev);
471 return snprintf(buf, PAGE_SIZE, "%u\n", size);
472 }
473
474 static ssize_t write_buffer_kb_store(struct device *csdev,
475 struct device_attribute *attr,
476 const char *buf, size_t count)
477 {
478 unsigned int minor = MINOR(csdev->devt);
479 struct comedi_device *dev;
480 struct comedi_subdevice *s;
481 unsigned int size;
482 int err;
483
484 err = kstrtouint(buf, 10, &size);
485 if (err)
486 return err;
487 if (size > (UINT_MAX / 1024))
488 return -EINVAL;
489 size *= 1024;
490
491 dev = comedi_dev_get_from_minor(minor);
492 if (!dev)
493 return -ENODEV;
494
495 mutex_lock(&dev->mutex);
496 s = comedi_write_subdevice(dev, minor);
497 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
498 err = resize_async_buffer(dev, s, size);
499 else
500 err = -EINVAL;
501 mutex_unlock(&dev->mutex);
502
503 comedi_dev_put(dev);
504 return err ? err : count;
505 }
506 static DEVICE_ATTR_RW(write_buffer_kb);
507
508 static struct attribute *comedi_dev_attrs[] = {
509 &dev_attr_max_read_buffer_kb.attr,
510 &dev_attr_read_buffer_kb.attr,
511 &dev_attr_max_write_buffer_kb.attr,
512 &dev_attr_write_buffer_kb.attr,
513 NULL,
514 };
515 ATTRIBUTE_GROUPS(comedi_dev);
516
517 static void comedi_set_subdevice_runflags(struct comedi_subdevice *s,
518 unsigned mask, unsigned bits)
519 {
520 unsigned long flags;
521
522 spin_lock_irqsave(&s->spin_lock, flags);
523 s->runflags &= ~mask;
524 s->runflags |= (bits & mask);
525 spin_unlock_irqrestore(&s->spin_lock, flags);
526 }
527
528 static unsigned comedi_get_subdevice_runflags(struct comedi_subdevice *s)
529 {
530 unsigned long flags;
531 unsigned runflags;
532
533 spin_lock_irqsave(&s->spin_lock, flags);
534 runflags = s->runflags;
535 spin_unlock_irqrestore(&s->spin_lock, flags);
536 return runflags;
537 }
538
539 bool comedi_is_subdevice_running(struct comedi_subdevice *s)
540 {
541 unsigned runflags = comedi_get_subdevice_runflags(s);
542
543 return (runflags & SRF_RUNNING) ? true : false;
544 }
545 EXPORT_SYMBOL_GPL(comedi_is_subdevice_running);
546
547 static bool comedi_is_subdevice_in_error(struct comedi_subdevice *s)
548 {
549 unsigned runflags = comedi_get_subdevice_runflags(s);
550
551 return (runflags & SRF_ERROR) ? true : false;
552 }
553
554 static bool comedi_is_subdevice_idle(struct comedi_subdevice *s)
555 {
556 unsigned runflags = comedi_get_subdevice_runflags(s);
557
558 return (runflags & (SRF_ERROR | SRF_RUNNING)) ? false : true;
559 }
560
561 /**
562 * comedi_alloc_spriv() - Allocate memory for the subdevice private data.
563 * @s: comedi_subdevice struct
564 * @size: size of the memory to allocate
565 *
566 * This also sets the subdevice runflags to allow the core to automatically
567 * free the private data during the detach.
568 */
569 void *comedi_alloc_spriv(struct comedi_subdevice *s, size_t size)
570 {
571 s->private = kzalloc(size, GFP_KERNEL);
572 if (s->private)
573 s->runflags |= SRF_FREE_SPRIV;
574 return s->private;
575 }
576 EXPORT_SYMBOL_GPL(comedi_alloc_spriv);
577
578 /*
579 This function restores a subdevice to an idle state.
580 */
581 static void do_become_nonbusy(struct comedi_device *dev,
582 struct comedi_subdevice *s)
583 {
584 struct comedi_async *async = s->async;
585
586 comedi_set_subdevice_runflags(s, SRF_RUNNING, 0);
587 if (async) {
588 comedi_buf_reset(s);
589 async->inttrig = NULL;
590 kfree(async->cmd.chanlist);
591 async->cmd.chanlist = NULL;
592 s->busy = NULL;
593 wake_up_interruptible_all(&s->async->wait_head);
594 } else {
595 dev_err(dev->class_dev,
596 "BUG: (?) do_become_nonbusy called with async=NULL\n");
597 s->busy = NULL;
598 }
599 }
600
601 static int do_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
602 {
603 int ret = 0;
604
605 if (comedi_is_subdevice_running(s) && s->cancel)
606 ret = s->cancel(dev, s);
607
608 do_become_nonbusy(dev, s);
609
610 return ret;
611 }
612
613 void comedi_device_cancel_all(struct comedi_device *dev)
614 {
615 struct comedi_subdevice *s;
616 int i;
617
618 if (!dev->attached)
619 return;
620
621 for (i = 0; i < dev->n_subdevices; i++) {
622 s = &dev->subdevices[i];
623 if (s->async)
624 do_cancel(dev, s);
625 }
626 }
627
628 static int is_device_busy(struct comedi_device *dev)
629 {
630 struct comedi_subdevice *s;
631 int i;
632
633 if (!dev->attached)
634 return 0;
635
636 for (i = 0; i < dev->n_subdevices; i++) {
637 s = &dev->subdevices[i];
638 if (s->busy)
639 return 1;
640 if (s->async && comedi_buf_is_mmapped(s))
641 return 1;
642 }
643
644 return 0;
645 }
646
647 /*
648 COMEDI_DEVCONFIG
649 device config ioctl
650
651 arg:
652 pointer to devconfig structure
653
654 reads:
655 devconfig structure at arg
656
657 writes:
658 none
659 */
660 static int do_devconfig_ioctl(struct comedi_device *dev,
661 struct comedi_devconfig __user *arg)
662 {
663 struct comedi_devconfig it;
664
665 if (!capable(CAP_SYS_ADMIN))
666 return -EPERM;
667
668 if (arg == NULL) {
669 if (is_device_busy(dev))
670 return -EBUSY;
671 if (dev->attached) {
672 struct module *driver_module = dev->driver->module;
673
674 comedi_device_detach(dev);
675 module_put(driver_module);
676 }
677 return 0;
678 }
679
680 if (copy_from_user(&it, arg, sizeof(it)))
681 return -EFAULT;
682
683 it.board_name[COMEDI_NAMELEN - 1] = 0;
684
685 if (it.options[COMEDI_DEVCONF_AUX_DATA_LENGTH]) {
686 dev_warn(dev->class_dev,
687 "comedi_config --init_data is deprecated\n");
688 return -EINVAL;
689 }
690
691 if (dev->minor >= comedi_num_legacy_minors)
692 /* don't re-use dynamically allocated comedi devices */
693 return -EBUSY;
694
695 /* This increments the driver module count on success. */
696 return comedi_device_attach(dev, &it);
697 }
698
699 /*
700 COMEDI_BUFCONFIG
701 buffer configuration ioctl
702
703 arg:
704 pointer to bufconfig structure
705
706 reads:
707 bufconfig at arg
708
709 writes:
710 modified bufconfig at arg
711
712 */
713 static int do_bufconfig_ioctl(struct comedi_device *dev,
714 struct comedi_bufconfig __user *arg)
715 {
716 struct comedi_bufconfig bc;
717 struct comedi_async *async;
718 struct comedi_subdevice *s;
719 int retval = 0;
720
721 if (copy_from_user(&bc, arg, sizeof(bc)))
722 return -EFAULT;
723
724 if (bc.subdevice >= dev->n_subdevices)
725 return -EINVAL;
726
727 s = &dev->subdevices[bc.subdevice];
728 async = s->async;
729
730 if (!async) {
731 dev_dbg(dev->class_dev,
732 "subdevice does not have async capability\n");
733 bc.size = 0;
734 bc.maximum_size = 0;
735 goto copyback;
736 }
737
738 if (bc.maximum_size) {
739 if (!capable(CAP_SYS_ADMIN))
740 return -EPERM;
741
742 async->max_bufsize = bc.maximum_size;
743 }
744
745 if (bc.size) {
746 retval = resize_async_buffer(dev, s, bc.size);
747 if (retval < 0)
748 return retval;
749 }
750
751 bc.size = async->prealloc_bufsz;
752 bc.maximum_size = async->max_bufsize;
753
754 copyback:
755 if (copy_to_user(arg, &bc, sizeof(bc)))
756 return -EFAULT;
757
758 return 0;
759 }
760
761 /*
762 COMEDI_DEVINFO
763 device info ioctl
764
765 arg:
766 pointer to devinfo structure
767
768 reads:
769 none
770
771 writes:
772 devinfo structure
773
774 */
775 static int do_devinfo_ioctl(struct comedi_device *dev,
776 struct comedi_devinfo __user *arg,
777 struct file *file)
778 {
779 const unsigned minor = iminor(file_inode(file));
780 struct comedi_subdevice *s;
781 struct comedi_devinfo devinfo;
782
783 memset(&devinfo, 0, sizeof(devinfo));
784
785 /* fill devinfo structure */
786 devinfo.version_code = COMEDI_VERSION_CODE;
787 devinfo.n_subdevs = dev->n_subdevices;
788 strlcpy(devinfo.driver_name, dev->driver->driver_name, COMEDI_NAMELEN);
789 strlcpy(devinfo.board_name, dev->board_name, COMEDI_NAMELEN);
790
791 s = comedi_read_subdevice(dev, minor);
792 if (s)
793 devinfo.read_subdevice = s->index;
794 else
795 devinfo.read_subdevice = -1;
796
797 s = comedi_write_subdevice(dev, minor);
798 if (s)
799 devinfo.write_subdevice = s->index;
800 else
801 devinfo.write_subdevice = -1;
802
803 if (copy_to_user(arg, &devinfo, sizeof(devinfo)))
804 return -EFAULT;
805
806 return 0;
807 }
808
809 /*
810 COMEDI_SUBDINFO
811 subdevice info ioctl
812
813 arg:
814 pointer to array of subdevice info structures
815
816 reads:
817 none
818
819 writes:
820 array of subdevice info structures at arg
821
822 */
823 static int do_subdinfo_ioctl(struct comedi_device *dev,
824 struct comedi_subdinfo __user *arg, void *file)
825 {
826 int ret, i;
827 struct comedi_subdinfo *tmp, *us;
828 struct comedi_subdevice *s;
829
830 tmp = kcalloc(dev->n_subdevices, sizeof(*tmp), GFP_KERNEL);
831 if (!tmp)
832 return -ENOMEM;
833
834 /* fill subdinfo structs */
835 for (i = 0; i < dev->n_subdevices; i++) {
836 s = &dev->subdevices[i];
837 us = tmp + i;
838
839 us->type = s->type;
840 us->n_chan = s->n_chan;
841 us->subd_flags = s->subdev_flags;
842 if (comedi_is_subdevice_running(s))
843 us->subd_flags |= SDF_RUNNING;
844 #define TIMER_nanosec 5 /* backwards compatibility */
845 us->timer_type = TIMER_nanosec;
846 us->len_chanlist = s->len_chanlist;
847 us->maxdata = s->maxdata;
848 if (s->range_table) {
849 us->range_type =
850 (i << 24) | (0 << 16) | (s->range_table->length);
851 } else {
852 us->range_type = 0; /* XXX */
853 }
854
855 if (s->busy)
856 us->subd_flags |= SDF_BUSY;
857 if (s->busy == file)
858 us->subd_flags |= SDF_BUSY_OWNER;
859 if (s->lock)
860 us->subd_flags |= SDF_LOCKED;
861 if (s->lock == file)
862 us->subd_flags |= SDF_LOCK_OWNER;
863 if (!s->maxdata && s->maxdata_list)
864 us->subd_flags |= SDF_MAXDATA;
865 if (s->range_table_list)
866 us->subd_flags |= SDF_RANGETYPE;
867 if (s->do_cmd)
868 us->subd_flags |= SDF_CMD;
869
870 if (s->insn_bits != &insn_inval)
871 us->insn_bits_support = COMEDI_SUPPORTED;
872 else
873 us->insn_bits_support = COMEDI_UNSUPPORTED;
874 }
875
876 ret = copy_to_user(arg, tmp, dev->n_subdevices * sizeof(*tmp));
877
878 kfree(tmp);
879
880 return ret ? -EFAULT : 0;
881 }
882
883 /*
884 COMEDI_CHANINFO
885 subdevice info ioctl
886
887 arg:
888 pointer to chaninfo structure
889
890 reads:
891 chaninfo structure at arg
892
893 writes:
894 arrays at elements of chaninfo structure
895
896 */
897 static int do_chaninfo_ioctl(struct comedi_device *dev,
898 struct comedi_chaninfo __user *arg)
899 {
900 struct comedi_subdevice *s;
901 struct comedi_chaninfo it;
902
903 if (copy_from_user(&it, arg, sizeof(it)))
904 return -EFAULT;
905
906 if (it.subdev >= dev->n_subdevices)
907 return -EINVAL;
908 s = &dev->subdevices[it.subdev];
909
910 if (it.maxdata_list) {
911 if (s->maxdata || !s->maxdata_list)
912 return -EINVAL;
913 if (copy_to_user(it.maxdata_list, s->maxdata_list,
914 s->n_chan * sizeof(unsigned int)))
915 return -EFAULT;
916 }
917
918 if (it.flaglist)
919 return -EINVAL; /* flaglist not supported */
920
921 if (it.rangelist) {
922 int i;
923
924 if (!s->range_table_list)
925 return -EINVAL;
926 for (i = 0; i < s->n_chan; i++) {
927 int x;
928
929 x = (dev->minor << 28) | (it.subdev << 24) | (i << 16) |
930 (s->range_table_list[i]->length);
931 if (put_user(x, it.rangelist + i))
932 return -EFAULT;
933 }
934 #if 0
935 if (copy_to_user(it.rangelist, s->range_type_list,
936 s->n_chan * sizeof(unsigned int)))
937 return -EFAULT;
938 #endif
939 }
940
941 return 0;
942 }
943
944 /*
945 COMEDI_BUFINFO
946 buffer information ioctl
947
948 arg:
949 pointer to bufinfo structure
950
951 reads:
952 bufinfo at arg
953
954 writes:
955 modified bufinfo at arg
956
957 */
958 static int do_bufinfo_ioctl(struct comedi_device *dev,
959 struct comedi_bufinfo __user *arg, void *file)
960 {
961 struct comedi_bufinfo bi;
962 struct comedi_subdevice *s;
963 struct comedi_async *async;
964
965 if (copy_from_user(&bi, arg, sizeof(bi)))
966 return -EFAULT;
967
968 if (bi.subdevice >= dev->n_subdevices)
969 return -EINVAL;
970
971 s = &dev->subdevices[bi.subdevice];
972
973 async = s->async;
974
975 if (!async) {
976 dev_dbg(dev->class_dev,
977 "subdevice does not have async capability\n");
978 bi.buf_write_ptr = 0;
979 bi.buf_read_ptr = 0;
980 bi.buf_write_count = 0;
981 bi.buf_read_count = 0;
982 bi.bytes_read = 0;
983 bi.bytes_written = 0;
984 goto copyback;
985 }
986 if (!s->busy) {
987 bi.bytes_read = 0;
988 bi.bytes_written = 0;
989 goto copyback_position;
990 }
991 if (s->busy != file)
992 return -EACCES;
993
994 if (bi.bytes_read && (s->subdev_flags & SDF_CMD_READ)) {
995 bi.bytes_read = comedi_buf_read_alloc(s, bi.bytes_read);
996 comedi_buf_read_free(s, bi.bytes_read);
997
998 if (comedi_is_subdevice_idle(s) &&
999 comedi_buf_n_bytes_ready(s) == 0) {
1000 do_become_nonbusy(dev, s);
1001 }
1002 }
1003
1004 if (bi.bytes_written && (s->subdev_flags & SDF_CMD_WRITE)) {
1005 bi.bytes_written =
1006 comedi_buf_write_alloc(s, bi.bytes_written);
1007 comedi_buf_write_free(s, bi.bytes_written);
1008 }
1009
1010 copyback_position:
1011 bi.buf_write_count = async->buf_write_count;
1012 bi.buf_write_ptr = async->buf_write_ptr;
1013 bi.buf_read_count = async->buf_read_count;
1014 bi.buf_read_ptr = async->buf_read_ptr;
1015
1016 copyback:
1017 if (copy_to_user(arg, &bi, sizeof(bi)))
1018 return -EFAULT;
1019
1020 return 0;
1021 }
1022
1023 static int check_insn_config_length(struct comedi_insn *insn,
1024 unsigned int *data)
1025 {
1026 if (insn->n < 1)
1027 return -EINVAL;
1028
1029 switch (data[0]) {
1030 case INSN_CONFIG_DIO_OUTPUT:
1031 case INSN_CONFIG_DIO_INPUT:
1032 case INSN_CONFIG_DISARM:
1033 case INSN_CONFIG_RESET:
1034 if (insn->n == 1)
1035 return 0;
1036 break;
1037 case INSN_CONFIG_ARM:
1038 case INSN_CONFIG_DIO_QUERY:
1039 case INSN_CONFIG_BLOCK_SIZE:
1040 case INSN_CONFIG_FILTER:
1041 case INSN_CONFIG_SERIAL_CLOCK:
1042 case INSN_CONFIG_BIDIRECTIONAL_DATA:
1043 case INSN_CONFIG_ALT_SOURCE:
1044 case INSN_CONFIG_SET_COUNTER_MODE:
1045 case INSN_CONFIG_8254_READ_STATUS:
1046 case INSN_CONFIG_SET_ROUTING:
1047 case INSN_CONFIG_GET_ROUTING:
1048 case INSN_CONFIG_GET_PWM_STATUS:
1049 case INSN_CONFIG_PWM_SET_PERIOD:
1050 case INSN_CONFIG_PWM_GET_PERIOD:
1051 if (insn->n == 2)
1052 return 0;
1053 break;
1054 case INSN_CONFIG_SET_GATE_SRC:
1055 case INSN_CONFIG_GET_GATE_SRC:
1056 case INSN_CONFIG_SET_CLOCK_SRC:
1057 case INSN_CONFIG_GET_CLOCK_SRC:
1058 case INSN_CONFIG_SET_OTHER_SRC:
1059 case INSN_CONFIG_GET_COUNTER_STATUS:
1060 case INSN_CONFIG_PWM_SET_H_BRIDGE:
1061 case INSN_CONFIG_PWM_GET_H_BRIDGE:
1062 case INSN_CONFIG_GET_HARDWARE_BUFFER_SIZE:
1063 if (insn->n == 3)
1064 return 0;
1065 break;
1066 case INSN_CONFIG_PWM_OUTPUT:
1067 case INSN_CONFIG_ANALOG_TRIG:
1068 if (insn->n == 5)
1069 return 0;
1070 break;
1071 case INSN_CONFIG_DIGITAL_TRIG:
1072 if (insn->n == 6)
1073 return 0;
1074 break;
1075 /* by default we allow the insn since we don't have checks for
1076 * all possible cases yet */
1077 default:
1078 pr_warn("No check for data length of config insn id %i is implemented\n",
1079 data[0]);
1080 pr_warn("Add a check to %s in %s\n", __func__, __FILE__);
1081 pr_warn("Assuming n=%i is correct\n", insn->n);
1082 return 0;
1083 }
1084 return -EINVAL;
1085 }
1086
1087 static int parse_insn(struct comedi_device *dev, struct comedi_insn *insn,
1088 unsigned int *data, void *file)
1089 {
1090 struct comedi_subdevice *s;
1091 int ret = 0;
1092 int i;
1093
1094 if (insn->insn & INSN_MASK_SPECIAL) {
1095 /* a non-subdevice instruction */
1096
1097 switch (insn->insn) {
1098 case INSN_GTOD:
1099 {
1100 struct timeval tv;
1101
1102 if (insn->n != 2) {
1103 ret = -EINVAL;
1104 break;
1105 }
1106
1107 do_gettimeofday(&tv);
1108 data[0] = tv.tv_sec;
1109 data[1] = tv.tv_usec;
1110 ret = 2;
1111
1112 break;
1113 }
1114 case INSN_WAIT:
1115 if (insn->n != 1 || data[0] >= 100000) {
1116 ret = -EINVAL;
1117 break;
1118 }
1119 udelay(data[0] / 1000);
1120 ret = 1;
1121 break;
1122 case INSN_INTTRIG:
1123 if (insn->n != 1) {
1124 ret = -EINVAL;
1125 break;
1126 }
1127 if (insn->subdev >= dev->n_subdevices) {
1128 dev_dbg(dev->class_dev,
1129 "%d not usable subdevice\n",
1130 insn->subdev);
1131 ret = -EINVAL;
1132 break;
1133 }
1134 s = &dev->subdevices[insn->subdev];
1135 if (!s->async) {
1136 dev_dbg(dev->class_dev, "no async\n");
1137 ret = -EINVAL;
1138 break;
1139 }
1140 if (!s->async->inttrig) {
1141 dev_dbg(dev->class_dev, "no inttrig\n");
1142 ret = -EAGAIN;
1143 break;
1144 }
1145 ret = s->async->inttrig(dev, s, data[0]);
1146 if (ret >= 0)
1147 ret = 1;
1148 break;
1149 default:
1150 dev_dbg(dev->class_dev, "invalid insn\n");
1151 ret = -EINVAL;
1152 break;
1153 }
1154 } else {
1155 /* a subdevice instruction */
1156 unsigned int maxdata;
1157
1158 if (insn->subdev >= dev->n_subdevices) {
1159 dev_dbg(dev->class_dev, "subdevice %d out of range\n",
1160 insn->subdev);
1161 ret = -EINVAL;
1162 goto out;
1163 }
1164 s = &dev->subdevices[insn->subdev];
1165
1166 if (s->type == COMEDI_SUBD_UNUSED) {
1167 dev_dbg(dev->class_dev, "%d not usable subdevice\n",
1168 insn->subdev);
1169 ret = -EIO;
1170 goto out;
1171 }
1172
1173 /* are we locked? (ioctl lock) */
1174 if (s->lock && s->lock != file) {
1175 dev_dbg(dev->class_dev, "device locked\n");
1176 ret = -EACCES;
1177 goto out;
1178 }
1179
1180 ret = comedi_check_chanlist(s, 1, &insn->chanspec);
1181 if (ret < 0) {
1182 ret = -EINVAL;
1183 dev_dbg(dev->class_dev, "bad chanspec\n");
1184 goto out;
1185 }
1186
1187 if (s->busy) {
1188 ret = -EBUSY;
1189 goto out;
1190 }
1191 /* This looks arbitrary. It is. */
1192 s->busy = &parse_insn;
1193 switch (insn->insn) {
1194 case INSN_READ:
1195 ret = s->insn_read(dev, s, insn, data);
1196 if (ret == -ETIMEDOUT) {
1197 dev_dbg(dev->class_dev,
1198 "subdevice %d read instruction timed out\n",
1199 s->index);
1200 }
1201 break;
1202 case INSN_WRITE:
1203 maxdata = s->maxdata_list
1204 ? s->maxdata_list[CR_CHAN(insn->chanspec)]
1205 : s->maxdata;
1206 for (i = 0; i < insn->n; ++i) {
1207 if (data[i] > maxdata) {
1208 ret = -EINVAL;
1209 dev_dbg(dev->class_dev,
1210 "bad data value(s)\n");
1211 break;
1212 }
1213 }
1214 if (ret == 0) {
1215 ret = s->insn_write(dev, s, insn, data);
1216 if (ret == -ETIMEDOUT) {
1217 dev_dbg(dev->class_dev,
1218 "subdevice %d write instruction timed out\n",
1219 s->index);
1220 }
1221 }
1222 break;
1223 case INSN_BITS:
1224 if (insn->n != 2) {
1225 ret = -EINVAL;
1226 } else {
1227 /* Most drivers ignore the base channel in
1228 * insn->chanspec. Fix this here if
1229 * the subdevice has <= 32 channels. */
1230 unsigned int orig_mask = data[0];
1231 unsigned int shift = 0;
1232
1233 if (s->n_chan <= 32) {
1234 shift = CR_CHAN(insn->chanspec);
1235 if (shift > 0) {
1236 insn->chanspec = 0;
1237 data[0] <<= shift;
1238 data[1] <<= shift;
1239 }
1240 }
1241 ret = s->insn_bits(dev, s, insn, data);
1242 data[0] = orig_mask;
1243 if (shift > 0)
1244 data[1] >>= shift;
1245 }
1246 break;
1247 case INSN_CONFIG:
1248 ret = check_insn_config_length(insn, data);
1249 if (ret)
1250 break;
1251 ret = s->insn_config(dev, s, insn, data);
1252 break;
1253 default:
1254 ret = -EINVAL;
1255 break;
1256 }
1257
1258 s->busy = NULL;
1259 }
1260
1261 out:
1262 return ret;
1263 }
1264
1265 /*
1266 * COMEDI_INSNLIST
1267 * synchronous instructions
1268 *
1269 * arg:
1270 * pointer to sync cmd structure
1271 *
1272 * reads:
1273 * sync cmd struct at arg
1274 * instruction list
1275 * data (for writes)
1276 *
1277 * writes:
1278 * data (for reads)
1279 */
1280 /* arbitrary limits */
1281 #define MAX_SAMPLES 256
1282 static int do_insnlist_ioctl(struct comedi_device *dev,
1283 struct comedi_insnlist __user *arg, void *file)
1284 {
1285 struct comedi_insnlist insnlist;
1286 struct comedi_insn *insns = NULL;
1287 unsigned int *data = NULL;
1288 int i = 0;
1289 int ret = 0;
1290
1291 if (copy_from_user(&insnlist, arg, sizeof(insnlist)))
1292 return -EFAULT;
1293
1294 data = kmalloc_array(MAX_SAMPLES, sizeof(unsigned int), GFP_KERNEL);
1295 if (!data) {
1296 ret = -ENOMEM;
1297 goto error;
1298 }
1299
1300 insns = kcalloc(insnlist.n_insns, sizeof(*insns), GFP_KERNEL);
1301 if (!insns) {
1302 ret = -ENOMEM;
1303 goto error;
1304 }
1305
1306 if (copy_from_user(insns, insnlist.insns,
1307 sizeof(*insns) * insnlist.n_insns)) {
1308 dev_dbg(dev->class_dev, "copy_from_user failed\n");
1309 ret = -EFAULT;
1310 goto error;
1311 }
1312
1313 for (i = 0; i < insnlist.n_insns; i++) {
1314 if (insns[i].n > MAX_SAMPLES) {
1315 dev_dbg(dev->class_dev,
1316 "number of samples too large\n");
1317 ret = -EINVAL;
1318 goto error;
1319 }
1320 if (insns[i].insn & INSN_MASK_WRITE) {
1321 if (copy_from_user(data, insns[i].data,
1322 insns[i].n * sizeof(unsigned int))) {
1323 dev_dbg(dev->class_dev,
1324 "copy_from_user failed\n");
1325 ret = -EFAULT;
1326 goto error;
1327 }
1328 }
1329 ret = parse_insn(dev, insns + i, data, file);
1330 if (ret < 0)
1331 goto error;
1332 if (insns[i].insn & INSN_MASK_READ) {
1333 if (copy_to_user(insns[i].data, data,
1334 insns[i].n * sizeof(unsigned int))) {
1335 dev_dbg(dev->class_dev,
1336 "copy_to_user failed\n");
1337 ret = -EFAULT;
1338 goto error;
1339 }
1340 }
1341 if (need_resched())
1342 schedule();
1343 }
1344
1345 error:
1346 kfree(insns);
1347 kfree(data);
1348
1349 if (ret < 0)
1350 return ret;
1351 return i;
1352 }
1353
1354 /*
1355 * COMEDI_INSN
1356 * synchronous instructions
1357 *
1358 * arg:
1359 * pointer to insn
1360 *
1361 * reads:
1362 * struct comedi_insn struct at arg
1363 * data (for writes)
1364 *
1365 * writes:
1366 * data (for reads)
1367 */
1368 static int do_insn_ioctl(struct comedi_device *dev,
1369 struct comedi_insn __user *arg, void *file)
1370 {
1371 struct comedi_insn insn;
1372 unsigned int *data = NULL;
1373 int ret = 0;
1374
1375 data = kmalloc_array(MAX_SAMPLES, sizeof(unsigned int), GFP_KERNEL);
1376 if (!data) {
1377 ret = -ENOMEM;
1378 goto error;
1379 }
1380
1381 if (copy_from_user(&insn, arg, sizeof(insn))) {
1382 ret = -EFAULT;
1383 goto error;
1384 }
1385
1386 /* This is where the behavior of insn and insnlist deviate. */
1387 if (insn.n > MAX_SAMPLES)
1388 insn.n = MAX_SAMPLES;
1389 if (insn.insn & INSN_MASK_WRITE) {
1390 if (copy_from_user(data,
1391 insn.data,
1392 insn.n * sizeof(unsigned int))) {
1393 ret = -EFAULT;
1394 goto error;
1395 }
1396 }
1397 ret = parse_insn(dev, &insn, data, file);
1398 if (ret < 0)
1399 goto error;
1400 if (insn.insn & INSN_MASK_READ) {
1401 if (copy_to_user(insn.data,
1402 data,
1403 insn.n * sizeof(unsigned int))) {
1404 ret = -EFAULT;
1405 goto error;
1406 }
1407 }
1408 ret = insn.n;
1409
1410 error:
1411 kfree(data);
1412
1413 return ret;
1414 }
1415
1416 static int __comedi_get_user_cmd(struct comedi_device *dev,
1417 struct comedi_cmd __user *arg,
1418 struct comedi_cmd *cmd)
1419 {
1420 struct comedi_subdevice *s;
1421
1422 if (copy_from_user(cmd, arg, sizeof(*cmd))) {
1423 dev_dbg(dev->class_dev, "bad cmd address\n");
1424 return -EFAULT;
1425 }
1426
1427 if (cmd->subdev >= dev->n_subdevices) {
1428 dev_dbg(dev->class_dev, "%d no such subdevice\n", cmd->subdev);
1429 return -ENODEV;
1430 }
1431
1432 s = &dev->subdevices[cmd->subdev];
1433
1434 if (s->type == COMEDI_SUBD_UNUSED) {
1435 dev_dbg(dev->class_dev, "%d not valid subdevice\n",
1436 cmd->subdev);
1437 return -EIO;
1438 }
1439
1440 if (!s->do_cmd || !s->do_cmdtest || !s->async) {
1441 dev_dbg(dev->class_dev,
1442 "subdevice %d does not support commands\n",
1443 cmd->subdev);
1444 return -EIO;
1445 }
1446
1447 /* make sure channel/gain list isn't too long */
1448 if (cmd->chanlist_len > s->len_chanlist) {
1449 dev_dbg(dev->class_dev, "channel/gain list too long %d > %d\n",
1450 cmd->chanlist_len, s->len_chanlist);
1451 return -EINVAL;
1452 }
1453
1454 return 0;
1455 }
1456
1457 static int __comedi_get_user_chanlist(struct comedi_device *dev,
1458 struct comedi_subdevice *s,
1459 unsigned int __user *user_chanlist,
1460 struct comedi_cmd *cmd)
1461 {
1462 unsigned int *chanlist;
1463 int ret;
1464
1465 /* user_chanlist could be NULL for do_cmdtest ioctls */
1466 if (!user_chanlist)
1467 return 0;
1468
1469 chanlist = memdup_user(user_chanlist,
1470 cmd->chanlist_len * sizeof(unsigned int));
1471 if (IS_ERR(chanlist))
1472 return PTR_ERR(chanlist);
1473
1474 /* make sure each element in channel/gain list is valid */
1475 ret = comedi_check_chanlist(s, cmd->chanlist_len, chanlist);
1476 if (ret < 0) {
1477 kfree(chanlist);
1478 return ret;
1479 }
1480
1481 cmd->chanlist = chanlist;
1482
1483 return 0;
1484 }
1485
1486 static int do_cmd_ioctl(struct comedi_device *dev,
1487 struct comedi_cmd __user *arg, void *file)
1488 {
1489 struct comedi_cmd cmd;
1490 struct comedi_subdevice *s;
1491 struct comedi_async *async;
1492 unsigned int __user *user_chanlist;
1493 int ret;
1494
1495 /* get the user's cmd and do some simple validation */
1496 ret = __comedi_get_user_cmd(dev, arg, &cmd);
1497 if (ret)
1498 return ret;
1499
1500 /* save user's chanlist pointer so it can be restored later */
1501 user_chanlist = (unsigned int __user *)cmd.chanlist;
1502
1503 s = &dev->subdevices[cmd.subdev];
1504 async = s->async;
1505
1506 /* are we locked? (ioctl lock) */
1507 if (s->lock && s->lock != file) {
1508 dev_dbg(dev->class_dev, "subdevice locked\n");
1509 return -EACCES;
1510 }
1511
1512 /* are we busy? */
1513 if (s->busy) {
1514 dev_dbg(dev->class_dev, "subdevice busy\n");
1515 return -EBUSY;
1516 }
1517
1518 /* make sure channel/gain list isn't too short */
1519 if (cmd.chanlist_len < 1) {
1520 dev_dbg(dev->class_dev, "channel/gain list too short %u < 1\n",
1521 cmd.chanlist_len);
1522 return -EINVAL;
1523 }
1524
1525 async->cmd = cmd;
1526 async->cmd.data = NULL;
1527
1528 /* load channel/gain list */
1529 ret = __comedi_get_user_chanlist(dev, s, user_chanlist, &async->cmd);
1530 if (ret)
1531 goto cleanup;
1532
1533 ret = s->do_cmdtest(dev, s, &async->cmd);
1534
1535 if (async->cmd.flags & CMDF_BOGUS || ret) {
1536 dev_dbg(dev->class_dev, "test returned %d\n", ret);
1537 cmd = async->cmd;
1538 /* restore chanlist pointer before copying back */
1539 cmd.chanlist = (unsigned int __force *)user_chanlist;
1540 cmd.data = NULL;
1541 if (copy_to_user(arg, &cmd, sizeof(cmd))) {
1542 dev_dbg(dev->class_dev, "fault writing cmd\n");
1543 ret = -EFAULT;
1544 goto cleanup;
1545 }
1546 ret = -EAGAIN;
1547 goto cleanup;
1548 }
1549
1550 if (!async->prealloc_bufsz) {
1551 ret = -ENOMEM;
1552 dev_dbg(dev->class_dev, "no buffer (?)\n");
1553 goto cleanup;
1554 }
1555
1556 comedi_buf_reset(s);
1557
1558 async->cb_mask =
1559 COMEDI_CB_EOA | COMEDI_CB_BLOCK | COMEDI_CB_ERROR |
1560 COMEDI_CB_OVERFLOW;
1561 if (async->cmd.flags & CMDF_WAKE_EOS)
1562 async->cb_mask |= COMEDI_CB_EOS;
1563
1564 comedi_set_subdevice_runflags(s, SRF_ERROR | SRF_RUNNING, SRF_RUNNING);
1565
1566 /* set s->busy _after_ setting SRF_RUNNING flag to avoid race with
1567 * comedi_read() or comedi_write() */
1568 s->busy = file;
1569 ret = s->do_cmd(dev, s);
1570 if (ret == 0)
1571 return 0;
1572
1573 cleanup:
1574 do_become_nonbusy(dev, s);
1575
1576 return ret;
1577 }
1578
1579 /*
1580 COMEDI_CMDTEST
1581 command testing ioctl
1582
1583 arg:
1584 pointer to cmd structure
1585
1586 reads:
1587 cmd structure at arg
1588 channel/range list
1589
1590 writes:
1591 modified cmd structure at arg
1592
1593 */
1594 static int do_cmdtest_ioctl(struct comedi_device *dev,
1595 struct comedi_cmd __user *arg, void *file)
1596 {
1597 struct comedi_cmd cmd;
1598 struct comedi_subdevice *s;
1599 unsigned int __user *user_chanlist;
1600 int ret;
1601
1602 /* get the user's cmd and do some simple validation */
1603 ret = __comedi_get_user_cmd(dev, arg, &cmd);
1604 if (ret)
1605 return ret;
1606
1607 /* save user's chanlist pointer so it can be restored later */
1608 user_chanlist = (unsigned int __user *)cmd.chanlist;
1609
1610 s = &dev->subdevices[cmd.subdev];
1611
1612 /* load channel/gain list */
1613 ret = __comedi_get_user_chanlist(dev, s, user_chanlist, &cmd);
1614 if (ret)
1615 return ret;
1616
1617 ret = s->do_cmdtest(dev, s, &cmd);
1618
1619 /* restore chanlist pointer before copying back */
1620 cmd.chanlist = (unsigned int __force *)user_chanlist;
1621
1622 if (copy_to_user(arg, &cmd, sizeof(cmd))) {
1623 dev_dbg(dev->class_dev, "bad cmd address\n");
1624 ret = -EFAULT;
1625 }
1626
1627 return ret;
1628 }
1629
1630 /*
1631 COMEDI_LOCK
1632 lock subdevice
1633
1634 arg:
1635 subdevice number
1636
1637 reads:
1638 none
1639
1640 writes:
1641 none
1642
1643 */
1644
1645 static int do_lock_ioctl(struct comedi_device *dev, unsigned int arg,
1646 void *file)
1647 {
1648 int ret = 0;
1649 unsigned long flags;
1650 struct comedi_subdevice *s;
1651
1652 if (arg >= dev->n_subdevices)
1653 return -EINVAL;
1654 s = &dev->subdevices[arg];
1655
1656 spin_lock_irqsave(&s->spin_lock, flags);
1657 if (s->busy || s->lock)
1658 ret = -EBUSY;
1659 else
1660 s->lock = file;
1661 spin_unlock_irqrestore(&s->spin_lock, flags);
1662
1663 return ret;
1664 }
1665
1666 /*
1667 COMEDI_UNLOCK
1668 unlock subdevice
1669
1670 arg:
1671 subdevice number
1672
1673 reads:
1674 none
1675
1676 writes:
1677 none
1678
1679 This function isn't protected by the semaphore, since
1680 we already own the lock.
1681 */
1682 static int do_unlock_ioctl(struct comedi_device *dev, unsigned int arg,
1683 void *file)
1684 {
1685 struct comedi_subdevice *s;
1686
1687 if (arg >= dev->n_subdevices)
1688 return -EINVAL;
1689 s = &dev->subdevices[arg];
1690
1691 if (s->busy)
1692 return -EBUSY;
1693
1694 if (s->lock && s->lock != file)
1695 return -EACCES;
1696
1697 if (s->lock == file)
1698 s->lock = NULL;
1699
1700 return 0;
1701 }
1702
1703 /*
1704 COMEDI_CANCEL
1705 cancel acquisition ioctl
1706
1707 arg:
1708 subdevice number
1709
1710 reads:
1711 nothing
1712
1713 writes:
1714 nothing
1715
1716 */
1717 static int do_cancel_ioctl(struct comedi_device *dev, unsigned int arg,
1718 void *file)
1719 {
1720 struct comedi_subdevice *s;
1721 int ret;
1722
1723 if (arg >= dev->n_subdevices)
1724 return -EINVAL;
1725 s = &dev->subdevices[arg];
1726 if (s->async == NULL)
1727 return -EINVAL;
1728
1729 if (!s->busy)
1730 return 0;
1731
1732 if (s->busy != file)
1733 return -EBUSY;
1734
1735 ret = do_cancel(dev, s);
1736
1737 return ret;
1738 }
1739
1740 /*
1741 COMEDI_POLL ioctl
1742 instructs driver to synchronize buffers
1743
1744 arg:
1745 subdevice number
1746
1747 reads:
1748 nothing
1749
1750 writes:
1751 nothing
1752
1753 */
1754 static int do_poll_ioctl(struct comedi_device *dev, unsigned int arg,
1755 void *file)
1756 {
1757 struct comedi_subdevice *s;
1758
1759 if (arg >= dev->n_subdevices)
1760 return -EINVAL;
1761 s = &dev->subdevices[arg];
1762
1763 if (!s->busy)
1764 return 0;
1765
1766 if (s->busy != file)
1767 return -EBUSY;
1768
1769 if (s->poll)
1770 return s->poll(dev, s);
1771
1772 return -EINVAL;
1773 }
1774
1775 static long comedi_unlocked_ioctl(struct file *file, unsigned int cmd,
1776 unsigned long arg)
1777 {
1778 const unsigned minor = iminor(file_inode(file));
1779 struct comedi_device *dev = file->private_data;
1780 int rc;
1781
1782 mutex_lock(&dev->mutex);
1783
1784 /* Device config is special, because it must work on
1785 * an unconfigured device. */
1786 if (cmd == COMEDI_DEVCONFIG) {
1787 if (minor >= COMEDI_NUM_BOARD_MINORS) {
1788 /* Device config not appropriate on non-board minors. */
1789 rc = -ENOTTY;
1790 goto done;
1791 }
1792 rc = do_devconfig_ioctl(dev,
1793 (struct comedi_devconfig __user *)arg);
1794 if (rc == 0) {
1795 if (arg == 0 &&
1796 dev->minor >= comedi_num_legacy_minors) {
1797 /* Successfully unconfigured a dynamically
1798 * allocated device. Try and remove it. */
1799 if (comedi_clear_board_dev(dev)) {
1800 mutex_unlock(&dev->mutex);
1801 comedi_free_board_dev(dev);
1802 return rc;
1803 }
1804 }
1805 }
1806 goto done;
1807 }
1808
1809 if (!dev->attached) {
1810 dev_dbg(dev->class_dev, "no driver attached\n");
1811 rc = -ENODEV;
1812 goto done;
1813 }
1814
1815 switch (cmd) {
1816 case COMEDI_BUFCONFIG:
1817 rc = do_bufconfig_ioctl(dev,
1818 (struct comedi_bufconfig __user *)arg);
1819 break;
1820 case COMEDI_DEVINFO:
1821 rc = do_devinfo_ioctl(dev, (struct comedi_devinfo __user *)arg,
1822 file);
1823 break;
1824 case COMEDI_SUBDINFO:
1825 rc = do_subdinfo_ioctl(dev,
1826 (struct comedi_subdinfo __user *)arg,
1827 file);
1828 break;
1829 case COMEDI_CHANINFO:
1830 rc = do_chaninfo_ioctl(dev, (void __user *)arg);
1831 break;
1832 case COMEDI_RANGEINFO:
1833 rc = do_rangeinfo_ioctl(dev, (void __user *)arg);
1834 break;
1835 case COMEDI_BUFINFO:
1836 rc = do_bufinfo_ioctl(dev,
1837 (struct comedi_bufinfo __user *)arg,
1838 file);
1839 break;
1840 case COMEDI_LOCK:
1841 rc = do_lock_ioctl(dev, arg, file);
1842 break;
1843 case COMEDI_UNLOCK:
1844 rc = do_unlock_ioctl(dev, arg, file);
1845 break;
1846 case COMEDI_CANCEL:
1847 rc = do_cancel_ioctl(dev, arg, file);
1848 break;
1849 case COMEDI_CMD:
1850 rc = do_cmd_ioctl(dev, (struct comedi_cmd __user *)arg, file);
1851 break;
1852 case COMEDI_CMDTEST:
1853 rc = do_cmdtest_ioctl(dev, (struct comedi_cmd __user *)arg,
1854 file);
1855 break;
1856 case COMEDI_INSNLIST:
1857 rc = do_insnlist_ioctl(dev,
1858 (struct comedi_insnlist __user *)arg,
1859 file);
1860 break;
1861 case COMEDI_INSN:
1862 rc = do_insn_ioctl(dev, (struct comedi_insn __user *)arg,
1863 file);
1864 break;
1865 case COMEDI_POLL:
1866 rc = do_poll_ioctl(dev, arg, file);
1867 break;
1868 default:
1869 rc = -ENOTTY;
1870 break;
1871 }
1872
1873 done:
1874 mutex_unlock(&dev->mutex);
1875 return rc;
1876 }
1877
1878 static void comedi_vm_open(struct vm_area_struct *area)
1879 {
1880 struct comedi_buf_map *bm;
1881
1882 bm = area->vm_private_data;
1883 comedi_buf_map_get(bm);
1884 }
1885
1886 static void comedi_vm_close(struct vm_area_struct *area)
1887 {
1888 struct comedi_buf_map *bm;
1889
1890 bm = area->vm_private_data;
1891 comedi_buf_map_put(bm);
1892 }
1893
1894 static struct vm_operations_struct comedi_vm_ops = {
1895 .open = comedi_vm_open,
1896 .close = comedi_vm_close,
1897 };
1898
1899 static int comedi_mmap(struct file *file, struct vm_area_struct *vma)
1900 {
1901 const unsigned minor = iminor(file_inode(file));
1902 struct comedi_device *dev = file->private_data;
1903 struct comedi_subdevice *s;
1904 struct comedi_async *async;
1905 struct comedi_buf_map *bm = NULL;
1906 unsigned long start = vma->vm_start;
1907 unsigned long size;
1908 int n_pages;
1909 int i;
1910 int retval;
1911
1912 /*
1913 * 'trylock' avoids circular dependency with current->mm->mmap_sem
1914 * and down-reading &dev->attach_lock should normally succeed without
1915 * contention unless the device is in the process of being attached
1916 * or detached.
1917 */
1918 if (!down_read_trylock(&dev->attach_lock))
1919 return -EAGAIN;
1920
1921 if (!dev->attached) {
1922 dev_dbg(dev->class_dev, "no driver attached\n");
1923 retval = -ENODEV;
1924 goto done;
1925 }
1926
1927 if (vma->vm_flags & VM_WRITE)
1928 s = comedi_write_subdevice(dev, minor);
1929 else
1930 s = comedi_read_subdevice(dev, minor);
1931 if (!s) {
1932 retval = -EINVAL;
1933 goto done;
1934 }
1935
1936 async = s->async;
1937 if (!async) {
1938 retval = -EINVAL;
1939 goto done;
1940 }
1941
1942 if (vma->vm_pgoff != 0) {
1943 dev_dbg(dev->class_dev, "mmap() offset must be 0.\n");
1944 retval = -EINVAL;
1945 goto done;
1946 }
1947
1948 size = vma->vm_end - vma->vm_start;
1949 if (size > async->prealloc_bufsz) {
1950 retval = -EFAULT;
1951 goto done;
1952 }
1953 if (size & (~PAGE_MASK)) {
1954 retval = -EFAULT;
1955 goto done;
1956 }
1957
1958 n_pages = size >> PAGE_SHIFT;
1959
1960 /* get reference to current buf map (if any) */
1961 bm = comedi_buf_map_from_subdev_get(s);
1962 if (!bm || n_pages > bm->n_pages) {
1963 retval = -EINVAL;
1964 goto done;
1965 }
1966 for (i = 0; i < n_pages; ++i) {
1967 struct comedi_buf_page *buf = &bm->page_list[i];
1968
1969 if (remap_pfn_range(vma, start,
1970 page_to_pfn(virt_to_page(buf->virt_addr)),
1971 PAGE_SIZE, PAGE_SHARED)) {
1972 retval = -EAGAIN;
1973 goto done;
1974 }
1975 start += PAGE_SIZE;
1976 }
1977
1978 vma->vm_ops = &comedi_vm_ops;
1979 vma->vm_private_data = bm;
1980
1981 vma->vm_ops->open(vma);
1982
1983 retval = 0;
1984 done:
1985 up_read(&dev->attach_lock);
1986 comedi_buf_map_put(bm); /* put reference to buf map - okay if NULL */
1987 return retval;
1988 }
1989
1990 static unsigned int comedi_poll(struct file *file, poll_table *wait)
1991 {
1992 unsigned int mask = 0;
1993 const unsigned minor = iminor(file_inode(file));
1994 struct comedi_device *dev = file->private_data;
1995 struct comedi_subdevice *s;
1996
1997 mutex_lock(&dev->mutex);
1998
1999 if (!dev->attached) {
2000 dev_dbg(dev->class_dev, "no driver attached\n");
2001 goto done;
2002 }
2003
2004 s = comedi_read_subdevice(dev, minor);
2005 if (s && s->async) {
2006 poll_wait(file, &s->async->wait_head, wait);
2007 if (!s->busy || !comedi_is_subdevice_running(s) ||
2008 comedi_buf_read_n_available(s) > 0)
2009 mask |= POLLIN | POLLRDNORM;
2010 }
2011
2012 s = comedi_write_subdevice(dev, minor);
2013 if (s && s->async) {
2014 unsigned int bps = bytes_per_sample(s);
2015
2016 poll_wait(file, &s->async->wait_head, wait);
2017 comedi_buf_write_alloc(s, s->async->prealloc_bufsz);
2018 if (!s->busy || !comedi_is_subdevice_running(s) ||
2019 comedi_buf_write_n_allocated(s) >= bps)
2020 mask |= POLLOUT | POLLWRNORM;
2021 }
2022
2023 done:
2024 mutex_unlock(&dev->mutex);
2025 return mask;
2026 }
2027
2028 static ssize_t comedi_write(struct file *file, const char __user *buf,
2029 size_t nbytes, loff_t *offset)
2030 {
2031 struct comedi_subdevice *s;
2032 struct comedi_async *async;
2033 int n, m, count = 0, retval = 0;
2034 DECLARE_WAITQUEUE(wait, current);
2035 const unsigned minor = iminor(file_inode(file));
2036 struct comedi_device *dev = file->private_data;
2037 bool on_wait_queue = false;
2038 bool attach_locked;
2039 unsigned int old_detach_count;
2040
2041 /* Protect against device detachment during operation. */
2042 down_read(&dev->attach_lock);
2043 attach_locked = true;
2044 old_detach_count = dev->detach_count;
2045
2046 if (!dev->attached) {
2047 dev_dbg(dev->class_dev, "no driver attached\n");
2048 retval = -ENODEV;
2049 goto out;
2050 }
2051
2052 s = comedi_write_subdevice(dev, minor);
2053 if (!s || !s->async) {
2054 retval = -EIO;
2055 goto out;
2056 }
2057
2058 async = s->async;
2059
2060 if (!s->busy || !nbytes)
2061 goto out;
2062 if (s->busy != file) {
2063 retval = -EACCES;
2064 goto out;
2065 }
2066
2067 add_wait_queue(&async->wait_head, &wait);
2068 on_wait_queue = true;
2069 while (nbytes > 0 && !retval) {
2070 set_current_state(TASK_INTERRUPTIBLE);
2071
2072 if (!comedi_is_subdevice_running(s)) {
2073 if (count == 0) {
2074 struct comedi_subdevice *new_s;
2075
2076 if (comedi_is_subdevice_in_error(s))
2077 retval = -EPIPE;
2078 else
2079 retval = 0;
2080 /*
2081 * To avoid deadlock, cannot acquire dev->mutex
2082 * while dev->attach_lock is held. Need to
2083 * remove task from the async wait queue before
2084 * releasing dev->attach_lock, as it might not
2085 * be valid afterwards.
2086 */
2087 remove_wait_queue(&async->wait_head, &wait);
2088 on_wait_queue = false;
2089 up_read(&dev->attach_lock);
2090 attach_locked = false;
2091 mutex_lock(&dev->mutex);
2092 /*
2093 * Become non-busy unless things have changed
2094 * behind our back. Checking dev->detach_count
2095 * is unchanged ought to be sufficient (unless
2096 * there have been 2**32 detaches in the
2097 * meantime!), but check the subdevice pointer
2098 * as well just in case.
2099 */
2100 new_s = comedi_write_subdevice(dev, minor);
2101 if (dev->attached &&
2102 old_detach_count == dev->detach_count &&
2103 s == new_s && new_s->async == async)
2104 do_become_nonbusy(dev, s);
2105 mutex_unlock(&dev->mutex);
2106 }
2107 break;
2108 }
2109
2110 n = nbytes;
2111
2112 m = n;
2113 if (async->buf_write_ptr + m > async->prealloc_bufsz)
2114 m = async->prealloc_bufsz - async->buf_write_ptr;
2115 comedi_buf_write_alloc(s, async->prealloc_bufsz);
2116 if (m > comedi_buf_write_n_allocated(s))
2117 m = comedi_buf_write_n_allocated(s);
2118 if (m < n)
2119 n = m;
2120
2121 if (n == 0) {
2122 if (file->f_flags & O_NONBLOCK) {
2123 retval = -EAGAIN;
2124 break;
2125 }
2126 schedule();
2127 if (signal_pending(current)) {
2128 retval = -ERESTARTSYS;
2129 break;
2130 }
2131 if (!s->busy)
2132 break;
2133 if (s->busy != file) {
2134 retval = -EACCES;
2135 break;
2136 }
2137 continue;
2138 }
2139
2140 m = copy_from_user(async->prealloc_buf + async->buf_write_ptr,
2141 buf, n);
2142 if (m) {
2143 n -= m;
2144 retval = -EFAULT;
2145 }
2146 comedi_buf_write_free(s, n);
2147
2148 count += n;
2149 nbytes -= n;
2150
2151 buf += n;
2152 break; /* makes device work like a pipe */
2153 }
2154 out:
2155 if (on_wait_queue)
2156 remove_wait_queue(&async->wait_head, &wait);
2157 set_current_state(TASK_RUNNING);
2158 if (attach_locked)
2159 up_read(&dev->attach_lock);
2160
2161 return count ? count : retval;
2162 }
2163
2164 static ssize_t comedi_read(struct file *file, char __user *buf, size_t nbytes,
2165 loff_t *offset)
2166 {
2167 struct comedi_subdevice *s;
2168 struct comedi_async *async;
2169 int n, m, count = 0, retval = 0;
2170 DECLARE_WAITQUEUE(wait, current);
2171 const unsigned minor = iminor(file_inode(file));
2172 struct comedi_device *dev = file->private_data;
2173 unsigned int old_detach_count;
2174 bool become_nonbusy = false;
2175 bool attach_locked;
2176
2177 /* Protect against device detachment during operation. */
2178 down_read(&dev->attach_lock);
2179 attach_locked = true;
2180 old_detach_count = dev->detach_count;
2181
2182 if (!dev->attached) {
2183 dev_dbg(dev->class_dev, "no driver attached\n");
2184 retval = -ENODEV;
2185 goto out;
2186 }
2187
2188 s = comedi_read_subdevice(dev, minor);
2189 if (!s || !s->async) {
2190 retval = -EIO;
2191 goto out;
2192 }
2193
2194 async = s->async;
2195 if (!s->busy || !nbytes)
2196 goto out;
2197 if (s->busy != file) {
2198 retval = -EACCES;
2199 goto out;
2200 }
2201
2202 add_wait_queue(&async->wait_head, &wait);
2203 while (nbytes > 0 && !retval) {
2204 set_current_state(TASK_INTERRUPTIBLE);
2205
2206 n = nbytes;
2207
2208 m = comedi_buf_read_n_available(s);
2209 if (async->buf_read_ptr + m > async->prealloc_bufsz)
2210 m = async->prealloc_bufsz - async->buf_read_ptr;
2211 if (m < n)
2212 n = m;
2213
2214 if (n == 0) {
2215 if (!comedi_is_subdevice_running(s)) {
2216 if (comedi_is_subdevice_in_error(s))
2217 retval = -EPIPE;
2218 else
2219 retval = 0;
2220 become_nonbusy = true;
2221 break;
2222 }
2223 if (file->f_flags & O_NONBLOCK) {
2224 retval = -EAGAIN;
2225 break;
2226 }
2227 schedule();
2228 if (signal_pending(current)) {
2229 retval = -ERESTARTSYS;
2230 break;
2231 }
2232 if (!s->busy) {
2233 retval = 0;
2234 break;
2235 }
2236 if (s->busy != file) {
2237 retval = -EACCES;
2238 break;
2239 }
2240 continue;
2241 }
2242 m = copy_to_user(buf, async->prealloc_buf +
2243 async->buf_read_ptr, n);
2244 if (m) {
2245 n -= m;
2246 retval = -EFAULT;
2247 }
2248
2249 comedi_buf_read_alloc(s, n);
2250 comedi_buf_read_free(s, n);
2251
2252 count += n;
2253 nbytes -= n;
2254
2255 buf += n;
2256 break; /* makes device work like a pipe */
2257 }
2258 remove_wait_queue(&async->wait_head, &wait);
2259 set_current_state(TASK_RUNNING);
2260 if (become_nonbusy || comedi_is_subdevice_idle(s)) {
2261 struct comedi_subdevice *new_s;
2262
2263 /*
2264 * To avoid deadlock, cannot acquire dev->mutex
2265 * while dev->attach_lock is held.
2266 */
2267 up_read(&dev->attach_lock);
2268 attach_locked = false;
2269 mutex_lock(&dev->mutex);
2270 /*
2271 * Check device hasn't become detached behind our back.
2272 * Checking dev->detach_count is unchanged ought to be
2273 * sufficient (unless there have been 2**32 detaches in the
2274 * meantime!), but check the subdevice pointer as well just in
2275 * case.
2276 */
2277 new_s = comedi_read_subdevice(dev, minor);
2278 if (dev->attached && old_detach_count == dev->detach_count &&
2279 s == new_s && new_s->async == async) {
2280 if (become_nonbusy || comedi_buf_n_bytes_ready(s) == 0)
2281 do_become_nonbusy(dev, s);
2282 }
2283 mutex_unlock(&dev->mutex);
2284 }
2285 out:
2286 if (attach_locked)
2287 up_read(&dev->attach_lock);
2288
2289 return count ? count : retval;
2290 }
2291
2292 static int comedi_open(struct inode *inode, struct file *file)
2293 {
2294 const unsigned minor = iminor(inode);
2295 struct comedi_device *dev = comedi_dev_get_from_minor(minor);
2296 int rc;
2297
2298 if (!dev) {
2299 pr_debug("invalid minor number\n");
2300 return -ENODEV;
2301 }
2302
2303 mutex_lock(&dev->mutex);
2304 if (!dev->attached && !capable(CAP_NET_ADMIN)) {
2305 dev_dbg(dev->class_dev, "not attached and not CAP_NET_ADMIN\n");
2306 rc = -ENODEV;
2307 goto out;
2308 }
2309 if (dev->attached && dev->use_count == 0) {
2310 if (!try_module_get(dev->driver->module)) {
2311 rc = -ENOSYS;
2312 goto out;
2313 }
2314 if (dev->open) {
2315 rc = dev->open(dev);
2316 if (rc < 0) {
2317 module_put(dev->driver->module);
2318 goto out;
2319 }
2320 }
2321 }
2322
2323 dev->use_count++;
2324 file->private_data = dev;
2325 rc = 0;
2326
2327 out:
2328 mutex_unlock(&dev->mutex);
2329 if (rc)
2330 comedi_dev_put(dev);
2331 return rc;
2332 }
2333
2334 static int comedi_fasync(int fd, struct file *file, int on)
2335 {
2336 struct comedi_device *dev = file->private_data;
2337
2338 return fasync_helper(fd, file, on, &dev->async_queue);
2339 }
2340
2341 static int comedi_close(struct inode *inode, struct file *file)
2342 {
2343 struct comedi_device *dev = file->private_data;
2344 struct comedi_subdevice *s = NULL;
2345 int i;
2346
2347 mutex_lock(&dev->mutex);
2348
2349 if (dev->subdevices) {
2350 for (i = 0; i < dev->n_subdevices; i++) {
2351 s = &dev->subdevices[i];
2352
2353 if (s->busy == file)
2354 do_cancel(dev, s);
2355 if (s->lock == file)
2356 s->lock = NULL;
2357 }
2358 }
2359 if (dev->attached && dev->use_count == 1) {
2360 if (dev->close)
2361 dev->close(dev);
2362 module_put(dev->driver->module);
2363 }
2364
2365 dev->use_count--;
2366
2367 mutex_unlock(&dev->mutex);
2368 comedi_dev_put(dev);
2369
2370 return 0;
2371 }
2372
2373 static const struct file_operations comedi_fops = {
2374 .owner = THIS_MODULE,
2375 .unlocked_ioctl = comedi_unlocked_ioctl,
2376 .compat_ioctl = comedi_compat_ioctl,
2377 .open = comedi_open,
2378 .release = comedi_close,
2379 .read = comedi_read,
2380 .write = comedi_write,
2381 .mmap = comedi_mmap,
2382 .poll = comedi_poll,
2383 .fasync = comedi_fasync,
2384 .llseek = noop_llseek,
2385 };
2386
2387 void comedi_event(struct comedi_device *dev, struct comedi_subdevice *s)
2388 {
2389 struct comedi_async *async = s->async;
2390 unsigned runflags = 0;
2391 unsigned runflags_mask = 0;
2392
2393 if (!comedi_is_subdevice_running(s))
2394 return;
2395
2396 if (s->
2397 async->events & (COMEDI_CB_EOA | COMEDI_CB_ERROR |
2398 COMEDI_CB_OVERFLOW)) {
2399 runflags_mask |= SRF_RUNNING;
2400 }
2401 /* remember if an error event has occurred, so an error
2402 * can be returned the next time the user does a read() */
2403 if (s->async->events & (COMEDI_CB_ERROR | COMEDI_CB_OVERFLOW)) {
2404 runflags_mask |= SRF_ERROR;
2405 runflags |= SRF_ERROR;
2406 }
2407 if (runflags_mask) {
2408 /*sets SRF_ERROR and SRF_RUNNING together atomically */
2409 comedi_set_subdevice_runflags(s, runflags_mask, runflags);
2410 }
2411
2412 if (async->cb_mask & s->async->events) {
2413 wake_up_interruptible(&async->wait_head);
2414 if (s->subdev_flags & SDF_CMD_READ)
2415 kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
2416 if (s->subdev_flags & SDF_CMD_WRITE)
2417 kill_fasync(&dev->async_queue, SIGIO, POLL_OUT);
2418 }
2419 s->async->events = 0;
2420 }
2421 EXPORT_SYMBOL_GPL(comedi_event);
2422
2423 /* Note: the ->mutex is pre-locked on successful return */
2424 struct comedi_device *comedi_alloc_board_minor(struct device *hardware_device)
2425 {
2426 struct comedi_device *dev;
2427 struct device *csdev;
2428 unsigned i;
2429
2430 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
2431 if (dev == NULL)
2432 return ERR_PTR(-ENOMEM);
2433 comedi_device_init(dev);
2434 comedi_set_hw_dev(dev, hardware_device);
2435 mutex_lock(&dev->mutex);
2436 mutex_lock(&comedi_board_minor_table_lock);
2437 for (i = hardware_device ? comedi_num_legacy_minors : 0;
2438 i < COMEDI_NUM_BOARD_MINORS; ++i) {
2439 if (comedi_board_minor_table[i] == NULL) {
2440 comedi_board_minor_table[i] = dev;
2441 break;
2442 }
2443 }
2444 mutex_unlock(&comedi_board_minor_table_lock);
2445 if (i == COMEDI_NUM_BOARD_MINORS) {
2446 mutex_unlock(&dev->mutex);
2447 comedi_device_cleanup(dev);
2448 comedi_dev_put(dev);
2449 pr_err("ran out of minor numbers for board device files\n");
2450 return ERR_PTR(-EBUSY);
2451 }
2452 dev->minor = i;
2453 csdev = device_create(comedi_class, hardware_device,
2454 MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i", i);
2455 if (!IS_ERR(csdev))
2456 dev->class_dev = get_device(csdev);
2457
2458 /* Note: dev->mutex needs to be unlocked by the caller. */
2459 return dev;
2460 }
2461
2462 static void comedi_free_board_minor(unsigned minor)
2463 {
2464 BUG_ON(minor >= COMEDI_NUM_BOARD_MINORS);
2465 comedi_free_board_dev(comedi_clear_board_minor(minor));
2466 }
2467
2468 void comedi_release_hardware_device(struct device *hardware_device)
2469 {
2470 int minor;
2471 struct comedi_device *dev;
2472
2473 for (minor = comedi_num_legacy_minors; minor < COMEDI_NUM_BOARD_MINORS;
2474 minor++) {
2475 mutex_lock(&comedi_board_minor_table_lock);
2476 dev = comedi_board_minor_table[minor];
2477 if (dev && dev->hw_dev == hardware_device) {
2478 comedi_board_minor_table[minor] = NULL;
2479 mutex_unlock(&comedi_board_minor_table_lock);
2480 comedi_free_board_dev(dev);
2481 break;
2482 }
2483 mutex_unlock(&comedi_board_minor_table_lock);
2484 }
2485 }
2486
2487 int comedi_alloc_subdevice_minor(struct comedi_subdevice *s)
2488 {
2489 struct comedi_device *dev = s->device;
2490 struct device *csdev;
2491 unsigned i;
2492
2493 mutex_lock(&comedi_subdevice_minor_table_lock);
2494 for (i = 0; i < COMEDI_NUM_SUBDEVICE_MINORS; ++i) {
2495 if (comedi_subdevice_minor_table[i] == NULL) {
2496 comedi_subdevice_minor_table[i] = s;
2497 break;
2498 }
2499 }
2500 mutex_unlock(&comedi_subdevice_minor_table_lock);
2501 if (i == COMEDI_NUM_SUBDEVICE_MINORS) {
2502 pr_err("ran out of minor numbers for subdevice files\n");
2503 return -EBUSY;
2504 }
2505 i += COMEDI_NUM_BOARD_MINORS;
2506 s->minor = i;
2507 csdev = device_create(comedi_class, dev->class_dev,
2508 MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i_subd%i",
2509 dev->minor, s->index);
2510 if (!IS_ERR(csdev))
2511 s->class_dev = csdev;
2512
2513 return 0;
2514 }
2515
2516 void comedi_free_subdevice_minor(struct comedi_subdevice *s)
2517 {
2518 unsigned int i;
2519
2520 if (s == NULL)
2521 return;
2522 if (s->minor < 0)
2523 return;
2524
2525 BUG_ON(s->minor >= COMEDI_NUM_MINORS);
2526 BUG_ON(s->minor < COMEDI_NUM_BOARD_MINORS);
2527
2528 i = s->minor - COMEDI_NUM_BOARD_MINORS;
2529 mutex_lock(&comedi_subdevice_minor_table_lock);
2530 if (s == comedi_subdevice_minor_table[i])
2531 comedi_subdevice_minor_table[i] = NULL;
2532 mutex_unlock(&comedi_subdevice_minor_table_lock);
2533 if (s->class_dev) {
2534 device_destroy(comedi_class, MKDEV(COMEDI_MAJOR, s->minor));
2535 s->class_dev = NULL;
2536 }
2537 }
2538
2539 static void comedi_cleanup_board_minors(void)
2540 {
2541 unsigned i;
2542
2543 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++)
2544 comedi_free_board_minor(i);
2545 }
2546
2547 static int __init comedi_init(void)
2548 {
2549 int i;
2550 int retval;
2551
2552 pr_info("version " COMEDI_RELEASE " - http://www.comedi.org\n");
2553
2554 if (comedi_num_legacy_minors < 0 ||
2555 comedi_num_legacy_minors > COMEDI_NUM_BOARD_MINORS) {
2556 pr_err("invalid value for module parameter \"comedi_num_legacy_minors\". Valid values are 0 through %i.\n",
2557 COMEDI_NUM_BOARD_MINORS);
2558 return -EINVAL;
2559 }
2560
2561 retval = register_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2562 COMEDI_NUM_MINORS, "comedi");
2563 if (retval)
2564 return -EIO;
2565 cdev_init(&comedi_cdev, &comedi_fops);
2566 comedi_cdev.owner = THIS_MODULE;
2567
2568 retval = kobject_set_name(&comedi_cdev.kobj, "comedi");
2569 if (retval) {
2570 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2571 COMEDI_NUM_MINORS);
2572 return retval;
2573 }
2574
2575 if (cdev_add(&comedi_cdev, MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS)) {
2576 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2577 COMEDI_NUM_MINORS);
2578 return -EIO;
2579 }
2580 comedi_class = class_create(THIS_MODULE, "comedi");
2581 if (IS_ERR(comedi_class)) {
2582 pr_err("failed to create class\n");
2583 cdev_del(&comedi_cdev);
2584 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2585 COMEDI_NUM_MINORS);
2586 return PTR_ERR(comedi_class);
2587 }
2588
2589 comedi_class->dev_groups = comedi_dev_groups;
2590
2591 /* XXX requires /proc interface */
2592 comedi_proc_init();
2593
2594 /* create devices files for legacy/manual use */
2595 for (i = 0; i < comedi_num_legacy_minors; i++) {
2596 struct comedi_device *dev;
2597
2598 dev = comedi_alloc_board_minor(NULL);
2599 if (IS_ERR(dev)) {
2600 comedi_cleanup_board_minors();
2601 cdev_del(&comedi_cdev);
2602 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2603 COMEDI_NUM_MINORS);
2604 return PTR_ERR(dev);
2605 }
2606 /* comedi_alloc_board_minor() locked the mutex */
2607 mutex_unlock(&dev->mutex);
2608 }
2609
2610 return 0;
2611 }
2612 module_init(comedi_init);
2613
2614 static void __exit comedi_cleanup(void)
2615 {
2616 int i;
2617
2618 comedi_cleanup_board_minors();
2619 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; ++i)
2620 BUG_ON(comedi_board_minor_table[i]);
2621 for (i = 0; i < COMEDI_NUM_SUBDEVICE_MINORS; ++i)
2622 BUG_ON(comedi_subdevice_minor_table[i]);
2623
2624 class_destroy(comedi_class);
2625 cdev_del(&comedi_cdev);
2626 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS);
2627
2628 comedi_proc_cleanup();
2629 }
2630 module_exit(comedi_cleanup);
2631
2632 MODULE_AUTHOR("http://www.comedi.org");
2633 MODULE_DESCRIPTION("Comedi core module");
2634 MODULE_LICENSE("GPL");
Linux kernel - Deliverables
This page took 0.081503 seconds and 6 git commands to generate.