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 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21
22 */
23
24 #undef DEBUG
25
26 #define __NO_VERSION__
27 #include "comedi_fops.h"
28 #include "comedi_compat32.h"
29
30 #include <linux/module.h>
31 #include <linux/errno.h>
32 #include <linux/kernel.h>
33 #include <linux/sched.h>
34 #include <linux/fcntl.h>
35 #include <linux/delay.h>
36 #include <linux/ioport.h>
37 #include <linux/mm.h>
38 #include <linux/slab.h>
39 #include <linux/kmod.h>
40 #include <linux/poll.h>
41 #include <linux/init.h>
42 #include <linux/device.h>
43 #include <linux/vmalloc.h>
44 #include <linux/fs.h>
45 #include "comedidev.h"
46 #include <linux/cdev.h>
47 #include <linux/stat.h>
48
49 #include <linux/io.h>
50 #include <linux/uaccess.h>
51
52 #include "internal.h"
53
54 MODULE_AUTHOR("http://www.comedi.org");
55 MODULE_DESCRIPTION("Comedi core module");
56 MODULE_LICENSE("GPL");
57
58 #ifdef CONFIG_COMEDI_DEBUG
59 int comedi_debug;
60 EXPORT_SYMBOL(comedi_debug);
61 module_param(comedi_debug, int, 0644);
62 #endif
63
64 bool comedi_autoconfig = 1;
65 module_param(comedi_autoconfig, bool, 0444);
66
67 static int comedi_num_legacy_minors;
68 module_param(comedi_num_legacy_minors, int, 0444);
69
70 static DEFINE_SPINLOCK(comedi_file_info_table_lock);
71 static struct comedi_device_file_info
72 *comedi_file_info_table[COMEDI_NUM_MINORS];
73
74 static int do_devconfig_ioctl(struct comedi_device *dev,
75 struct comedi_devconfig __user *arg);
76 static int do_bufconfig_ioctl(struct comedi_device *dev,
77 struct comedi_bufconfig __user *arg);
78 static int do_devinfo_ioctl(struct comedi_device *dev,
79 struct comedi_devinfo __user *arg,
80 struct file *file);
81 static int do_subdinfo_ioctl(struct comedi_device *dev,
82 struct comedi_subdinfo __user *arg, void *file);
83 static int do_chaninfo_ioctl(struct comedi_device *dev,
84 struct comedi_chaninfo __user *arg);
85 static int do_bufinfo_ioctl(struct comedi_device *dev,
86 struct comedi_bufinfo __user *arg, void *file);
87 static int do_cmd_ioctl(struct comedi_device *dev,
88 struct comedi_cmd __user *arg, void *file);
89 static int do_lock_ioctl(struct comedi_device *dev, unsigned int arg,
90 void *file);
91 static int do_unlock_ioctl(struct comedi_device *dev, unsigned int arg,
92 void *file);
93 static int do_cancel_ioctl(struct comedi_device *dev, unsigned int arg,
94 void *file);
95 static int do_cmdtest_ioctl(struct comedi_device *dev,
96 struct comedi_cmd __user *arg, void *file);
97 static int do_insnlist_ioctl(struct comedi_device *dev,
98 struct comedi_insnlist __user *arg, void *file);
99 static int do_insn_ioctl(struct comedi_device *dev,
100 struct comedi_insn __user *arg, void *file);
101 static int do_poll_ioctl(struct comedi_device *dev, unsigned int subd,
102 void *file);
103
104 static void do_become_nonbusy(struct comedi_device *dev,
105 struct comedi_subdevice *s);
106 static int do_cancel(struct comedi_device *dev, struct comedi_subdevice *s);
107
108 static int comedi_fasync(int fd, struct file *file, int on);
109
110 static int is_device_busy(struct comedi_device *dev);
111 static int resize_async_buffer(struct comedi_device *dev,
112 struct comedi_subdevice *s,
113 struct comedi_async *async, unsigned new_size);
114
115 /* declarations for sysfs attribute files */
116 static struct device_attribute dev_attr_max_read_buffer_kb;
117 static struct device_attribute dev_attr_read_buffer_kb;
118 static struct device_attribute dev_attr_max_write_buffer_kb;
119 static struct device_attribute dev_attr_write_buffer_kb;
120
comedi_unlocked_ioctl(struct file * file,unsigned int cmd,unsigned long arg)121 static long comedi_unlocked_ioctl(struct file *file, unsigned int cmd,
122 unsigned long arg)
123 {
124 const unsigned minor = iminor(file->f_dentry->d_inode);
125 struct comedi_device_file_info *dev_file_info =
126 comedi_get_device_file_info(minor);
127 struct comedi_device *dev;
128 int rc;
129
130 if (dev_file_info == NULL || dev_file_info->device == NULL)
131 return -ENODEV;
132 dev = dev_file_info->device;
133
134 mutex_lock(&dev->mutex);
135
136 /* Device config is special, because it must work on
137 * an unconfigured device. */
138 if (cmd == COMEDI_DEVCONFIG) {
139 if (minor >= COMEDI_NUM_BOARD_MINORS) {
140 /* Device config not appropriate on non-board minors. */
141 rc = -ENOTTY;
142 goto done;
143 }
144 rc = do_devconfig_ioctl(dev,
145 (struct comedi_devconfig __user *)arg);
146 if (rc == 0)
147 /* Evade comedi_auto_unconfig(). */
148 dev_file_info->hardware_device = NULL;
149 goto done;
150 }
151
152 if (!dev->attached) {
153 DPRINTK("no driver configured on /dev/comedi%i\n", dev->minor);
154 rc = -ENODEV;
155 goto done;
156 }
157
158 switch (cmd) {
159 case COMEDI_BUFCONFIG:
160 rc = do_bufconfig_ioctl(dev,
161 (struct comedi_bufconfig __user *)arg);
162 break;
163 case COMEDI_DEVINFO:
164 rc = do_devinfo_ioctl(dev, (struct comedi_devinfo __user *)arg,
165 file);
166 break;
167 case COMEDI_SUBDINFO:
168 rc = do_subdinfo_ioctl(dev,
169 (struct comedi_subdinfo __user *)arg,
170 file);
171 break;
172 case COMEDI_CHANINFO:
173 rc = do_chaninfo_ioctl(dev, (void __user *)arg);
174 break;
175 case COMEDI_RANGEINFO:
176 rc = do_rangeinfo_ioctl(dev, (void __user *)arg);
177 break;
178 case COMEDI_BUFINFO:
179 rc = do_bufinfo_ioctl(dev,
180 (struct comedi_bufinfo __user *)arg,
181 file);
182 break;
183 case COMEDI_LOCK:
184 rc = do_lock_ioctl(dev, arg, file);
185 break;
186 case COMEDI_UNLOCK:
187 rc = do_unlock_ioctl(dev, arg, file);
188 break;
189 case COMEDI_CANCEL:
190 rc = do_cancel_ioctl(dev, arg, file);
191 break;
192 case COMEDI_CMD:
193 rc = do_cmd_ioctl(dev, (struct comedi_cmd __user *)arg, file);
194 break;
195 case COMEDI_CMDTEST:
196 rc = do_cmdtest_ioctl(dev, (struct comedi_cmd __user *)arg,
197 file);
198 break;
199 case COMEDI_INSNLIST:
200 rc = do_insnlist_ioctl(dev,
201 (struct comedi_insnlist __user *)arg,
202 file);
203 break;
204 case COMEDI_INSN:
205 rc = do_insn_ioctl(dev, (struct comedi_insn __user *)arg,
206 file);
207 break;
208 case COMEDI_POLL:
209 rc = do_poll_ioctl(dev, arg, file);
210 break;
211 default:
212 rc = -ENOTTY;
213 break;
214 }
215
216 done:
217 mutex_unlock(&dev->mutex);
218 return rc;
219 }
220
221 /*
222 COMEDI_DEVCONFIG
223 device config ioctl
224
225 arg:
226 pointer to devconfig structure
227
228 reads:
229 devconfig structure at arg
230
231 writes:
232 none
233 */
do_devconfig_ioctl(struct comedi_device * dev,struct comedi_devconfig __user * arg)234 static int do_devconfig_ioctl(struct comedi_device *dev,
235 struct comedi_devconfig __user *arg)
236 {
237 struct comedi_devconfig it;
238 int ret;
239 unsigned char *aux_data = NULL;
240 int aux_len;
241
242 if (!capable(CAP_SYS_ADMIN))
243 return -EPERM;
244
245 if (arg == NULL) {
246 if (is_device_busy(dev))
247 return -EBUSY;
248 if (dev->attached) {
249 struct module *driver_module = dev->driver->module;
250 comedi_device_detach(dev);
251 module_put(driver_module);
252 }
253 return 0;
254 }
255
256 if (copy_from_user(&it, arg, sizeof(struct comedi_devconfig)))
257 return -EFAULT;
258
259 it.board_name[COMEDI_NAMELEN - 1] = 0;
260
261 if (comedi_aux_data(it.options, 0) &&
262 it.options[COMEDI_DEVCONF_AUX_DATA_LENGTH]) {
263 int bit_shift;
264 aux_len = it.options[COMEDI_DEVCONF_AUX_DATA_LENGTH];
265 if (aux_len < 0)
266 return -EFAULT;
267
268 aux_data = vmalloc(aux_len);
269 if (!aux_data)
270 return -ENOMEM;
271
272 if (copy_from_user(aux_data,
273 comedi_aux_data(it.options, 0), aux_len)) {
274 vfree(aux_data);
275 return -EFAULT;
276 }
277 it.options[COMEDI_DEVCONF_AUX_DATA_LO] =
278 (unsigned long)aux_data;
279 if (sizeof(void *) > sizeof(int)) {
280 bit_shift = sizeof(int) * 8;
281 it.options[COMEDI_DEVCONF_AUX_DATA_HI] =
282 ((unsigned long)aux_data) >> bit_shift;
283 } else
284 it.options[COMEDI_DEVCONF_AUX_DATA_HI] = 0;
285 }
286
287 ret = comedi_device_attach(dev, &it);
288 if (ret == 0) {
289 if (!try_module_get(dev->driver->module)) {
290 comedi_device_detach(dev);
291 ret = -ENOSYS;
292 }
293 }
294
295 if (aux_data)
296 vfree(aux_data);
297
298 return ret;
299 }
300
301 /*
302 COMEDI_BUFCONFIG
303 buffer configuration ioctl
304
305 arg:
306 pointer to bufconfig structure
307
308 reads:
309 bufconfig at arg
310
311 writes:
312 modified bufconfig at arg
313
314 */
do_bufconfig_ioctl(struct comedi_device * dev,struct comedi_bufconfig __user * arg)315 static int do_bufconfig_ioctl(struct comedi_device *dev,
316 struct comedi_bufconfig __user *arg)
317 {
318 struct comedi_bufconfig bc;
319 struct comedi_async *async;
320 struct comedi_subdevice *s;
321 int retval = 0;
322
323 if (copy_from_user(&bc, arg, sizeof(struct comedi_bufconfig)))
324 return -EFAULT;
325
326 if (bc.subdevice >= dev->n_subdevices || bc.subdevice < 0)
327 return -EINVAL;
328
329 s = dev->subdevices + bc.subdevice;
330 async = s->async;
331
332 if (!async) {
333 DPRINTK("subdevice does not have async capability\n");
334 bc.size = 0;
335 bc.maximum_size = 0;
336 goto copyback;
337 }
338
339 if (bc.maximum_size) {
340 if (!capable(CAP_SYS_ADMIN))
341 return -EPERM;
342
343 async->max_bufsize = bc.maximum_size;
344 }
345
346 if (bc.size) {
347 retval = resize_async_buffer(dev, s, async, bc.size);
348 if (retval < 0)
349 return retval;
350 }
351
352 bc.size = async->prealloc_bufsz;
353 bc.maximum_size = async->max_bufsize;
354
355 copyback:
356 if (copy_to_user(arg, &bc, sizeof(struct comedi_bufconfig)))
357 return -EFAULT;
358
359 return 0;
360 }
361
362 /*
363 COMEDI_DEVINFO
364 device info ioctl
365
366 arg:
367 pointer to devinfo structure
368
369 reads:
370 none
371
372 writes:
373 devinfo structure
374
375 */
do_devinfo_ioctl(struct comedi_device * dev,struct comedi_devinfo __user * arg,struct file * file)376 static int do_devinfo_ioctl(struct comedi_device *dev,
377 struct comedi_devinfo __user *arg,
378 struct file *file)
379 {
380 struct comedi_devinfo devinfo;
381 const unsigned minor = iminor(file->f_dentry->d_inode);
382 struct comedi_device_file_info *dev_file_info =
383 comedi_get_device_file_info(minor);
384 struct comedi_subdevice *read_subdev =
385 comedi_get_read_subdevice(dev_file_info);
386 struct comedi_subdevice *write_subdev =
387 comedi_get_write_subdevice(dev_file_info);
388
389 memset(&devinfo, 0, sizeof(devinfo));
390
391 /* fill devinfo structure */
392 devinfo.version_code = COMEDI_VERSION_CODE;
393 devinfo.n_subdevs = dev->n_subdevices;
394 strlcpy(devinfo.driver_name, dev->driver->driver_name, COMEDI_NAMELEN);
395 strlcpy(devinfo.board_name, dev->board_name, COMEDI_NAMELEN);
396
397 if (read_subdev)
398 devinfo.read_subdevice = read_subdev - dev->subdevices;
399 else
400 devinfo.read_subdevice = -1;
401
402 if (write_subdev)
403 devinfo.write_subdevice = write_subdev - dev->subdevices;
404 else
405 devinfo.write_subdevice = -1;
406
407 if (copy_to_user(arg, &devinfo, sizeof(struct comedi_devinfo)))
408 return -EFAULT;
409
410 return 0;
411 }
412
413 /*
414 COMEDI_SUBDINFO
415 subdevice info ioctl
416
417 arg:
418 pointer to array of subdevice info structures
419
420 reads:
421 none
422
423 writes:
424 array of subdevice info structures at arg
425
426 */
do_subdinfo_ioctl(struct comedi_device * dev,struct comedi_subdinfo __user * arg,void * file)427 static int do_subdinfo_ioctl(struct comedi_device *dev,
428 struct comedi_subdinfo __user *arg, void *file)
429 {
430 int ret, i;
431 struct comedi_subdinfo *tmp, *us;
432 struct comedi_subdevice *s;
433
434 tmp =
435 kcalloc(dev->n_subdevices, sizeof(struct comedi_subdinfo),
436 GFP_KERNEL);
437 if (!tmp)
438 return -ENOMEM;
439
440 /* fill subdinfo structs */
441 for (i = 0; i < dev->n_subdevices; i++) {
442 s = dev->subdevices + i;
443 us = tmp + i;
444
445 us->type = s->type;
446 us->n_chan = s->n_chan;
447 us->subd_flags = s->subdev_flags;
448 if (comedi_get_subdevice_runflags(s) & SRF_RUNNING)
449 us->subd_flags |= SDF_RUNNING;
450 #define TIMER_nanosec 5 /* backwards compatibility */
451 us->timer_type = TIMER_nanosec;
452 us->len_chanlist = s->len_chanlist;
453 us->maxdata = s->maxdata;
454 if (s->range_table) {
455 us->range_type =
456 (i << 24) | (0 << 16) | (s->range_table->length);
457 } else {
458 us->range_type = 0; /* XXX */
459 }
460 us->flags = s->flags;
461
462 if (s->busy)
463 us->subd_flags |= SDF_BUSY;
464 if (s->busy == file)
465 us->subd_flags |= SDF_BUSY_OWNER;
466 if (s->lock)
467 us->subd_flags |= SDF_LOCKED;
468 if (s->lock == file)
469 us->subd_flags |= SDF_LOCK_OWNER;
470 if (!s->maxdata && s->maxdata_list)
471 us->subd_flags |= SDF_MAXDATA;
472 if (s->flaglist)
473 us->subd_flags |= SDF_FLAGS;
474 if (s->range_table_list)
475 us->subd_flags |= SDF_RANGETYPE;
476 if (s->do_cmd)
477 us->subd_flags |= SDF_CMD;
478
479 if (s->insn_bits != &insn_inval)
480 us->insn_bits_support = COMEDI_SUPPORTED;
481 else
482 us->insn_bits_support = COMEDI_UNSUPPORTED;
483
484 us->settling_time_0 = s->settling_time_0;
485 }
486
487 ret = copy_to_user(arg, tmp,
488 dev->n_subdevices * sizeof(struct comedi_subdinfo));
489
490 kfree(tmp);
491
492 return ret ? -EFAULT : 0;
493 }
494
495 /*
496 COMEDI_CHANINFO
497 subdevice info ioctl
498
499 arg:
500 pointer to chaninfo structure
501
502 reads:
503 chaninfo structure at arg
504
505 writes:
506 arrays at elements of chaninfo structure
507
508 */
do_chaninfo_ioctl(struct comedi_device * dev,struct comedi_chaninfo __user * arg)509 static int do_chaninfo_ioctl(struct comedi_device *dev,
510 struct comedi_chaninfo __user *arg)
511 {
512 struct comedi_subdevice *s;
513 struct comedi_chaninfo it;
514
515 if (copy_from_user(&it, arg, sizeof(struct comedi_chaninfo)))
516 return -EFAULT;
517
518 if (it.subdev >= dev->n_subdevices)
519 return -EINVAL;
520 s = dev->subdevices + it.subdev;
521
522 if (it.maxdata_list) {
523 if (s->maxdata || !s->maxdata_list)
524 return -EINVAL;
525 if (copy_to_user(it.maxdata_list, s->maxdata_list,
526 s->n_chan * sizeof(unsigned int)))
527 return -EFAULT;
528 }
529
530 if (it.flaglist) {
531 if (!s->flaglist)
532 return -EINVAL;
533 if (copy_to_user(it.flaglist, s->flaglist,
534 s->n_chan * sizeof(unsigned int)))
535 return -EFAULT;
536 }
537
538 if (it.rangelist) {
539 int i;
540
541 if (!s->range_table_list)
542 return -EINVAL;
543 for (i = 0; i < s->n_chan; i++) {
544 int x;
545
546 x = (dev->minor << 28) | (it.subdev << 24) | (i << 16) |
547 (s->range_table_list[i]->length);
548 if (put_user(x, it.rangelist + i))
549 return -EFAULT;
550 }
551 #if 0
552 if (copy_to_user(it.rangelist, s->range_type_list,
553 s->n_chan * sizeof(unsigned int)))
554 return -EFAULT;
555 #endif
556 }
557
558 return 0;
559 }
560
561 /*
562 COMEDI_BUFINFO
563 buffer information ioctl
564
565 arg:
566 pointer to bufinfo structure
567
568 reads:
569 bufinfo at arg
570
571 writes:
572 modified bufinfo at arg
573
574 */
do_bufinfo_ioctl(struct comedi_device * dev,struct comedi_bufinfo __user * arg,void * file)575 static int do_bufinfo_ioctl(struct comedi_device *dev,
576 struct comedi_bufinfo __user *arg, void *file)
577 {
578 struct comedi_bufinfo bi;
579 struct comedi_subdevice *s;
580 struct comedi_async *async;
581
582 if (copy_from_user(&bi, arg, sizeof(struct comedi_bufinfo)))
583 return -EFAULT;
584
585 if (bi.subdevice >= dev->n_subdevices || bi.subdevice < 0)
586 return -EINVAL;
587
588 s = dev->subdevices + bi.subdevice;
589
590 if (s->lock && s->lock != file)
591 return -EACCES;
592
593 async = s->async;
594
595 if (!async) {
596 DPRINTK("subdevice does not have async capability\n");
597 bi.buf_write_ptr = 0;
598 bi.buf_read_ptr = 0;
599 bi.buf_write_count = 0;
600 bi.buf_read_count = 0;
601 bi.bytes_read = 0;
602 bi.bytes_written = 0;
603 goto copyback;
604 }
605 if (!s->busy) {
606 bi.bytes_read = 0;
607 bi.bytes_written = 0;
608 goto copyback_position;
609 }
610 if (s->busy != file)
611 return -EACCES;
612
613 if (bi.bytes_read && (s->subdev_flags & SDF_CMD_READ)) {
614 bi.bytes_read = comedi_buf_read_alloc(async, bi.bytes_read);
615 comedi_buf_read_free(async, bi.bytes_read);
616
617 if (!(comedi_get_subdevice_runflags(s) & (SRF_ERROR |
618 SRF_RUNNING))
619 && async->buf_write_count == async->buf_read_count) {
620 do_become_nonbusy(dev, s);
621 }
622 }
623
624 if (bi.bytes_written && (s->subdev_flags & SDF_CMD_WRITE)) {
625 bi.bytes_written =
626 comedi_buf_write_alloc(async, bi.bytes_written);
627 comedi_buf_write_free(async, bi.bytes_written);
628 }
629
630 copyback_position:
631 bi.buf_write_count = async->buf_write_count;
632 bi.buf_write_ptr = async->buf_write_ptr;
633 bi.buf_read_count = async->buf_read_count;
634 bi.buf_read_ptr = async->buf_read_ptr;
635
636 copyback:
637 if (copy_to_user(arg, &bi, sizeof(struct comedi_bufinfo)))
638 return -EFAULT;
639
640 return 0;
641 }
642
643 static int parse_insn(struct comedi_device *dev, struct comedi_insn *insn,
644 unsigned int *data, void *file);
645 /*
646 * COMEDI_INSNLIST
647 * synchronous instructions
648 *
649 * arg:
650 * pointer to sync cmd structure
651 *
652 * reads:
653 * sync cmd struct at arg
654 * instruction list
655 * data (for writes)
656 *
657 * writes:
658 * data (for reads)
659 */
660 /* arbitrary limits */
661 #define MAX_SAMPLES 256
do_insnlist_ioctl(struct comedi_device * dev,struct comedi_insnlist __user * arg,void * file)662 static int do_insnlist_ioctl(struct comedi_device *dev,
663 struct comedi_insnlist __user *arg, void *file)
664 {
665 struct comedi_insnlist insnlist;
666 struct comedi_insn *insns = NULL;
667 unsigned int *data = NULL;
668 int i = 0;
669 int ret = 0;
670
671 if (copy_from_user(&insnlist, arg, sizeof(struct comedi_insnlist)))
672 return -EFAULT;
673
674 data = kmalloc(sizeof(unsigned int) * MAX_SAMPLES, GFP_KERNEL);
675 if (!data) {
676 DPRINTK("kmalloc failed\n");
677 ret = -ENOMEM;
678 goto error;
679 }
680
681 insns =
682 kcalloc(insnlist.n_insns, sizeof(struct comedi_insn), GFP_KERNEL);
683 if (!insns) {
684 DPRINTK("kmalloc failed\n");
685 ret = -ENOMEM;
686 goto error;
687 }
688
689 if (copy_from_user(insns, insnlist.insns,
690 sizeof(struct comedi_insn) * insnlist.n_insns)) {
691 DPRINTK("copy_from_user failed\n");
692 ret = -EFAULT;
693 goto error;
694 }
695
696 for (i = 0; i < insnlist.n_insns; i++) {
697 if (insns[i].n > MAX_SAMPLES) {
698 DPRINTK("number of samples too large\n");
699 ret = -EINVAL;
700 goto error;
701 }
702 if (insns[i].insn & INSN_MASK_WRITE) {
703 if (copy_from_user(data, insns[i].data,
704 insns[i].n * sizeof(unsigned int))) {
705 DPRINTK("copy_from_user failed\n");
706 ret = -EFAULT;
707 goto error;
708 }
709 }
710 ret = parse_insn(dev, insns + i, data, file);
711 if (ret < 0)
712 goto error;
713 if (insns[i].insn & INSN_MASK_READ) {
714 if (copy_to_user(insns[i].data, data,
715 insns[i].n * sizeof(unsigned int))) {
716 DPRINTK("copy_to_user failed\n");
717 ret = -EFAULT;
718 goto error;
719 }
720 }
721 if (need_resched())
722 schedule();
723 }
724
725 error:
726 kfree(insns);
727 kfree(data);
728
729 if (ret < 0)
730 return ret;
731 return i;
732 }
733
check_insn_config_length(struct comedi_insn * insn,unsigned int * data)734 static int check_insn_config_length(struct comedi_insn *insn,
735 unsigned int *data)
736 {
737 if (insn->n < 1)
738 return -EINVAL;
739
740 switch (data[0]) {
741 case INSN_CONFIG_DIO_OUTPUT:
742 case INSN_CONFIG_DIO_INPUT:
743 case INSN_CONFIG_DISARM:
744 case INSN_CONFIG_RESET:
745 if (insn->n == 1)
746 return 0;
747 break;
748 case INSN_CONFIG_ARM:
749 case INSN_CONFIG_DIO_QUERY:
750 case INSN_CONFIG_BLOCK_SIZE:
751 case INSN_CONFIG_FILTER:
752 case INSN_CONFIG_SERIAL_CLOCK:
753 case INSN_CONFIG_BIDIRECTIONAL_DATA:
754 case INSN_CONFIG_ALT_SOURCE:
755 case INSN_CONFIG_SET_COUNTER_MODE:
756 case INSN_CONFIG_8254_READ_STATUS:
757 case INSN_CONFIG_SET_ROUTING:
758 case INSN_CONFIG_GET_ROUTING:
759 case INSN_CONFIG_GET_PWM_STATUS:
760 case INSN_CONFIG_PWM_SET_PERIOD:
761 case INSN_CONFIG_PWM_GET_PERIOD:
762 if (insn->n == 2)
763 return 0;
764 break;
765 case INSN_CONFIG_SET_GATE_SRC:
766 case INSN_CONFIG_GET_GATE_SRC:
767 case INSN_CONFIG_SET_CLOCK_SRC:
768 case INSN_CONFIG_GET_CLOCK_SRC:
769 case INSN_CONFIG_SET_OTHER_SRC:
770 case INSN_CONFIG_GET_COUNTER_STATUS:
771 case INSN_CONFIG_PWM_SET_H_BRIDGE:
772 case INSN_CONFIG_PWM_GET_H_BRIDGE:
773 case INSN_CONFIG_GET_HARDWARE_BUFFER_SIZE:
774 if (insn->n == 3)
775 return 0;
776 break;
777 case INSN_CONFIG_PWM_OUTPUT:
778 case INSN_CONFIG_ANALOG_TRIG:
779 if (insn->n == 5)
780 return 0;
781 break;
782 /* by default we allow the insn since we don't have checks for
783 * all possible cases yet */
784 default:
785 printk(KERN_WARNING
786 "comedi: no check for data length of config insn id "
787 "%i is implemented.\n"
788 " Add a check to %s in %s.\n"
789 " Assuming n=%i is correct.\n", data[0], __func__,
790 __FILE__, insn->n);
791 return 0;
792 break;
793 }
794 return -EINVAL;
795 }
796
parse_insn(struct comedi_device * dev,struct comedi_insn * insn,unsigned int * data,void * file)797 static int parse_insn(struct comedi_device *dev, struct comedi_insn *insn,
798 unsigned int *data, void *file)
799 {
800 struct comedi_subdevice *s;
801 int ret = 0;
802 int i;
803
804 if (insn->insn & INSN_MASK_SPECIAL) {
805 /* a non-subdevice instruction */
806
807 switch (insn->insn) {
808 case INSN_GTOD:
809 {
810 struct timeval tv;
811
812 if (insn->n != 2) {
813 ret = -EINVAL;
814 break;
815 }
816
817 do_gettimeofday(&tv);
818 data[0] = tv.tv_sec;
819 data[1] = tv.tv_usec;
820 ret = 2;
821
822 break;
823 }
824 case INSN_WAIT:
825 if (insn->n != 1 || data[0] >= 100000) {
826 ret = -EINVAL;
827 break;
828 }
829 udelay(data[0] / 1000);
830 ret = 1;
831 break;
832 case INSN_INTTRIG:
833 if (insn->n != 1) {
834 ret = -EINVAL;
835 break;
836 }
837 if (insn->subdev >= dev->n_subdevices) {
838 DPRINTK("%d not usable subdevice\n",
839 insn->subdev);
840 ret = -EINVAL;
841 break;
842 }
843 s = dev->subdevices + insn->subdev;
844 if (!s->async) {
845 DPRINTK("no async\n");
846 ret = -EINVAL;
847 break;
848 }
849 if (!s->async->inttrig) {
850 DPRINTK("no inttrig\n");
851 ret = -EAGAIN;
852 break;
853 }
854 ret = s->async->inttrig(dev, s, data[0]);
855 if (ret >= 0)
856 ret = 1;
857 break;
858 default:
859 DPRINTK("invalid insn\n");
860 ret = -EINVAL;
861 break;
862 }
863 } else {
864 /* a subdevice instruction */
865 unsigned int maxdata;
866
867 if (insn->subdev >= dev->n_subdevices) {
868 DPRINTK("subdevice %d out of range\n", insn->subdev);
869 ret = -EINVAL;
870 goto out;
871 }
872 s = dev->subdevices + insn->subdev;
873
874 if (s->type == COMEDI_SUBD_UNUSED) {
875 DPRINTK("%d not usable subdevice\n", insn->subdev);
876 ret = -EIO;
877 goto out;
878 }
879
880 /* are we locked? (ioctl lock) */
881 if (s->lock && s->lock != file) {
882 DPRINTK("device locked\n");
883 ret = -EACCES;
884 goto out;
885 }
886
887 ret = comedi_check_chanlist(s, 1, &insn->chanspec);
888 if (ret < 0) {
889 ret = -EINVAL;
890 DPRINTK("bad chanspec\n");
891 goto out;
892 }
893
894 if (s->busy) {
895 ret = -EBUSY;
896 goto out;
897 }
898 /* This looks arbitrary. It is. */
899 s->busy = &parse_insn;
900 switch (insn->insn) {
901 case INSN_READ:
902 ret = s->insn_read(dev, s, insn, data);
903 break;
904 case INSN_WRITE:
905 maxdata = s->maxdata_list
906 ? s->maxdata_list[CR_CHAN(insn->chanspec)]
907 : s->maxdata;
908 for (i = 0; i < insn->n; ++i) {
909 if (data[i] > maxdata) {
910 ret = -EINVAL;
911 DPRINTK("bad data value(s)\n");
912 break;
913 }
914 }
915 if (ret == 0)
916 ret = s->insn_write(dev, s, insn, data);
917 break;
918 case INSN_BITS:
919 if (insn->n != 2) {
920 ret = -EINVAL;
921 } else {
922 /* Most drivers ignore the base channel in
923 * insn->chanspec. Fix this here if
924 * the subdevice has <= 32 channels. */
925 unsigned int shift;
926 unsigned int orig_mask;
927
928 orig_mask = data[0];
929 if (s->n_chan <= 32) {
930 shift = CR_CHAN(insn->chanspec);
931 if (shift > 0) {
932 insn->chanspec = 0;
933 data[0] <<= shift;
934 data[1] <<= shift;
935 }
936 } else
937 shift = 0;
938 ret = s->insn_bits(dev, s, insn, data);
939 data[0] = orig_mask;
940 if (shift > 0)
941 data[1] >>= shift;
942 }
943 break;
944 case INSN_CONFIG:
945 ret = check_insn_config_length(insn, data);
946 if (ret)
947 break;
948 ret = s->insn_config(dev, s, insn, data);
949 break;
950 default:
951 ret = -EINVAL;
952 break;
953 }
954
955 s->busy = NULL;
956 }
957
958 out:
959 return ret;
960 }
961
962 /*
963 * COMEDI_INSN
964 * synchronous instructions
965 *
966 * arg:
967 * pointer to insn
968 *
969 * reads:
970 * struct comedi_insn struct at arg
971 * data (for writes)
972 *
973 * writes:
974 * data (for reads)
975 */
do_insn_ioctl(struct comedi_device * dev,struct comedi_insn __user * arg,void * file)976 static int do_insn_ioctl(struct comedi_device *dev,
977 struct comedi_insn __user *arg, void *file)
978 {
979 struct comedi_insn insn;
980 unsigned int *data = NULL;
981 int ret = 0;
982
983 data = kmalloc(sizeof(unsigned int) * MAX_SAMPLES, GFP_KERNEL);
984 if (!data) {
985 ret = -ENOMEM;
986 goto error;
987 }
988
989 if (copy_from_user(&insn, arg, sizeof(struct comedi_insn))) {
990 ret = -EFAULT;
991 goto error;
992 }
993
994 /* This is where the behavior of insn and insnlist deviate. */
995 if (insn.n > MAX_SAMPLES)
996 insn.n = MAX_SAMPLES;
997 if (insn.insn & INSN_MASK_WRITE) {
998 if (copy_from_user(data,
999 insn.data,
1000 insn.n * sizeof(unsigned int))) {
1001 ret = -EFAULT;
1002 goto error;
1003 }
1004 }
1005 ret = parse_insn(dev, &insn, data, file);
1006 if (ret < 0)
1007 goto error;
1008 if (insn.insn & INSN_MASK_READ) {
1009 if (copy_to_user(insn.data,
1010 data,
1011 insn.n * sizeof(unsigned int))) {
1012 ret = -EFAULT;
1013 goto error;
1014 }
1015 }
1016 ret = insn.n;
1017
1018 error:
1019 kfree(data);
1020
1021 return ret;
1022 }
1023
comedi_set_subdevice_runflags(struct comedi_subdevice * s,unsigned mask,unsigned bits)1024 static void comedi_set_subdevice_runflags(struct comedi_subdevice *s,
1025 unsigned mask, unsigned bits)
1026 {
1027 unsigned long flags;
1028
1029 spin_lock_irqsave(&s->spin_lock, flags);
1030 s->runflags &= ~mask;
1031 s->runflags |= (bits & mask);
1032 spin_unlock_irqrestore(&s->spin_lock, flags);
1033 }
1034
do_cmd_ioctl(struct comedi_device * dev,struct comedi_cmd __user * cmd,void * file)1035 static int do_cmd_ioctl(struct comedi_device *dev,
1036 struct comedi_cmd __user *cmd, void *file)
1037 {
1038 struct comedi_cmd user_cmd;
1039 struct comedi_subdevice *s;
1040 struct comedi_async *async;
1041 int ret = 0;
1042 unsigned int __user *chanlist_saver = NULL;
1043
1044 if (copy_from_user(&user_cmd, cmd, sizeof(struct comedi_cmd))) {
1045 DPRINTK("bad cmd address\n");
1046 return -EFAULT;
1047 }
1048 /* save user's chanlist pointer so it can be restored later */
1049 chanlist_saver = user_cmd.chanlist;
1050
1051 if (user_cmd.subdev >= dev->n_subdevices) {
1052 DPRINTK("%d no such subdevice\n", user_cmd.subdev);
1053 return -ENODEV;
1054 }
1055
1056 s = dev->subdevices + user_cmd.subdev;
1057 async = s->async;
1058
1059 if (s->type == COMEDI_SUBD_UNUSED) {
1060 DPRINTK("%d not valid subdevice\n", user_cmd.subdev);
1061 return -EIO;
1062 }
1063
1064 if (!s->do_cmd || !s->do_cmdtest || !s->async) {
1065 DPRINTK("subdevice %i does not support commands\n",
1066 user_cmd.subdev);
1067 return -EIO;
1068 }
1069
1070 /* are we locked? (ioctl lock) */
1071 if (s->lock && s->lock != file) {
1072 DPRINTK("subdevice locked\n");
1073 return -EACCES;
1074 }
1075
1076 /* are we busy? */
1077 if (s->busy) {
1078 DPRINTK("subdevice busy\n");
1079 return -EBUSY;
1080 }
1081
1082 /* make sure channel/gain list isn't too long */
1083 if (user_cmd.chanlist_len > s->len_chanlist) {
1084 DPRINTK("channel/gain list too long %u > %d\n",
1085 user_cmd.chanlist_len, s->len_chanlist);
1086 return -EINVAL;
1087 }
1088
1089 /* make sure channel/gain list isn't too short */
1090 if (user_cmd.chanlist_len < 1) {
1091 DPRINTK("channel/gain list too short %u < 1\n",
1092 user_cmd.chanlist_len);
1093 return -EINVAL;
1094 }
1095
1096 async->cmd = user_cmd;
1097 async->cmd.data = NULL;
1098 /* load channel/gain list */
1099 async->cmd.chanlist =
1100 kmalloc(async->cmd.chanlist_len * sizeof(int), GFP_KERNEL);
1101 if (!async->cmd.chanlist) {
1102 DPRINTK("allocation failed\n");
1103 return -ENOMEM;
1104 }
1105
1106 if (copy_from_user(async->cmd.chanlist, user_cmd.chanlist,
1107 async->cmd.chanlist_len * sizeof(int))) {
1108 DPRINTK("fault reading chanlist\n");
1109 ret = -EFAULT;
1110 goto cleanup;
1111 }
1112
1113 /* make sure each element in channel/gain list is valid */
1114 ret = comedi_check_chanlist(s,
1115 async->cmd.chanlist_len,
1116 async->cmd.chanlist);
1117 if (ret < 0) {
1118 DPRINTK("bad chanlist\n");
1119 goto cleanup;
1120 }
1121
1122 ret = s->do_cmdtest(dev, s, &async->cmd);
1123
1124 if (async->cmd.flags & TRIG_BOGUS || ret) {
1125 DPRINTK("test returned %d\n", ret);
1126 user_cmd = async->cmd;
1127 /* restore chanlist pointer before copying back */
1128 user_cmd.chanlist = chanlist_saver;
1129 user_cmd.data = NULL;
1130 if (copy_to_user(cmd, &user_cmd, sizeof(struct comedi_cmd))) {
1131 DPRINTK("fault writing cmd\n");
1132 ret = -EFAULT;
1133 goto cleanup;
1134 }
1135 ret = -EAGAIN;
1136 goto cleanup;
1137 }
1138
1139 if (!async->prealloc_bufsz) {
1140 ret = -ENOMEM;
1141 DPRINTK("no buffer (?)\n");
1142 goto cleanup;
1143 }
1144
1145 comedi_reset_async_buf(async);
1146
1147 async->cb_mask =
1148 COMEDI_CB_EOA | COMEDI_CB_BLOCK | COMEDI_CB_ERROR |
1149 COMEDI_CB_OVERFLOW;
1150 if (async->cmd.flags & TRIG_WAKE_EOS)
1151 async->cb_mask |= COMEDI_CB_EOS;
1152
1153 comedi_set_subdevice_runflags(s, ~0, SRF_USER | SRF_RUNNING);
1154
1155 /* set s->busy _after_ setting SRF_RUNNING flag to avoid race with
1156 * comedi_read() or comedi_write() */
1157 s->busy = file;
1158 ret = s->do_cmd(dev, s);
1159 if (ret == 0)
1160 return 0;
1161
1162 cleanup:
1163 do_become_nonbusy(dev, s);
1164
1165 return ret;
1166 }
1167
1168 /*
1169 COMEDI_CMDTEST
1170 command testing ioctl
1171
1172 arg:
1173 pointer to cmd structure
1174
1175 reads:
1176 cmd structure at arg
1177 channel/range list
1178
1179 writes:
1180 modified cmd structure at arg
1181
1182 */
do_cmdtest_ioctl(struct comedi_device * dev,struct comedi_cmd __user * arg,void * file)1183 static int do_cmdtest_ioctl(struct comedi_device *dev,
1184 struct comedi_cmd __user *arg, void *file)
1185 {
1186 struct comedi_cmd user_cmd;
1187 struct comedi_subdevice *s;
1188 int ret = 0;
1189 unsigned int *chanlist = NULL;
1190 unsigned int __user *chanlist_saver = NULL;
1191
1192 if (copy_from_user(&user_cmd, arg, sizeof(struct comedi_cmd))) {
1193 DPRINTK("bad cmd address\n");
1194 return -EFAULT;
1195 }
1196 /* save user's chanlist pointer so it can be restored later */
1197 chanlist_saver = user_cmd.chanlist;
1198
1199 if (user_cmd.subdev >= dev->n_subdevices) {
1200 DPRINTK("%d no such subdevice\n", user_cmd.subdev);
1201 return -ENODEV;
1202 }
1203
1204 s = dev->subdevices + user_cmd.subdev;
1205 if (s->type == COMEDI_SUBD_UNUSED) {
1206 DPRINTK("%d not valid subdevice\n", user_cmd.subdev);
1207 return -EIO;
1208 }
1209
1210 if (!s->do_cmd || !s->do_cmdtest) {
1211 DPRINTK("subdevice %i does not support commands\n",
1212 user_cmd.subdev);
1213 return -EIO;
1214 }
1215
1216 /* make sure channel/gain list isn't too long */
1217 if (user_cmd.chanlist_len > s->len_chanlist) {
1218 DPRINTK("channel/gain list too long %d > %d\n",
1219 user_cmd.chanlist_len, s->len_chanlist);
1220 ret = -EINVAL;
1221 goto cleanup;
1222 }
1223
1224 /* load channel/gain list */
1225 if (user_cmd.chanlist) {
1226 chanlist =
1227 kmalloc(user_cmd.chanlist_len * sizeof(int), GFP_KERNEL);
1228 if (!chanlist) {
1229 DPRINTK("allocation failed\n");
1230 ret = -ENOMEM;
1231 goto cleanup;
1232 }
1233
1234 if (copy_from_user(chanlist, user_cmd.chanlist,
1235 user_cmd.chanlist_len * sizeof(int))) {
1236 DPRINTK("fault reading chanlist\n");
1237 ret = -EFAULT;
1238 goto cleanup;
1239 }
1240
1241 /* make sure each element in channel/gain list is valid */
1242 ret = comedi_check_chanlist(s, user_cmd.chanlist_len, chanlist);
1243 if (ret < 0) {
1244 DPRINTK("bad chanlist\n");
1245 goto cleanup;
1246 }
1247
1248 user_cmd.chanlist = chanlist;
1249 }
1250
1251 ret = s->do_cmdtest(dev, s, &user_cmd);
1252
1253 /* restore chanlist pointer before copying back */
1254 user_cmd.chanlist = chanlist_saver;
1255
1256 if (copy_to_user(arg, &user_cmd, sizeof(struct comedi_cmd))) {
1257 DPRINTK("bad cmd address\n");
1258 ret = -EFAULT;
1259 goto cleanup;
1260 }
1261 cleanup:
1262 kfree(chanlist);
1263
1264 return ret;
1265 }
1266
1267 /*
1268 COMEDI_LOCK
1269 lock subdevice
1270
1271 arg:
1272 subdevice number
1273
1274 reads:
1275 none
1276
1277 writes:
1278 none
1279
1280 */
1281
do_lock_ioctl(struct comedi_device * dev,unsigned int arg,void * file)1282 static int do_lock_ioctl(struct comedi_device *dev, unsigned int arg,
1283 void *file)
1284 {
1285 int ret = 0;
1286 unsigned long flags;
1287 struct comedi_subdevice *s;
1288
1289 if (arg >= dev->n_subdevices)
1290 return -EINVAL;
1291 s = dev->subdevices + arg;
1292
1293 spin_lock_irqsave(&s->spin_lock, flags);
1294 if (s->busy || s->lock)
1295 ret = -EBUSY;
1296 else
1297 s->lock = file;
1298 spin_unlock_irqrestore(&s->spin_lock, flags);
1299
1300 #if 0
1301 if (ret < 0)
1302 return ret;
1303
1304 if (s->lock_f)
1305 ret = s->lock_f(dev, s);
1306 #endif
1307
1308 return ret;
1309 }
1310
1311 /*
1312 COMEDI_UNLOCK
1313 unlock subdevice
1314
1315 arg:
1316 subdevice number
1317
1318 reads:
1319 none
1320
1321 writes:
1322 none
1323
1324 This function isn't protected by the semaphore, since
1325 we already own the lock.
1326 */
do_unlock_ioctl(struct comedi_device * dev,unsigned int arg,void * file)1327 static int do_unlock_ioctl(struct comedi_device *dev, unsigned int arg,
1328 void *file)
1329 {
1330 struct comedi_subdevice *s;
1331
1332 if (arg >= dev->n_subdevices)
1333 return -EINVAL;
1334 s = dev->subdevices + arg;
1335
1336 if (s->busy)
1337 return -EBUSY;
1338
1339 if (s->lock && s->lock != file)
1340 return -EACCES;
1341
1342 if (s->lock == file) {
1343 #if 0
1344 if (s->unlock)
1345 s->unlock(dev, s);
1346 #endif
1347
1348 s->lock = NULL;
1349 }
1350
1351 return 0;
1352 }
1353
1354 /*
1355 COMEDI_CANCEL
1356 cancel acquisition ioctl
1357
1358 arg:
1359 subdevice number
1360
1361 reads:
1362 nothing
1363
1364 writes:
1365 nothing
1366
1367 */
do_cancel_ioctl(struct comedi_device * dev,unsigned int arg,void * file)1368 static int do_cancel_ioctl(struct comedi_device *dev, unsigned int arg,
1369 void *file)
1370 {
1371 struct comedi_subdevice *s;
1372 int ret;
1373
1374 if (arg >= dev->n_subdevices)
1375 return -EINVAL;
1376 s = dev->subdevices + arg;
1377 if (s->async == NULL)
1378 return -EINVAL;
1379
1380 if (s->lock && s->lock != file)
1381 return -EACCES;
1382
1383 if (!s->busy)
1384 return 0;
1385
1386 if (s->busy != file)
1387 return -EBUSY;
1388
1389 ret = do_cancel(dev, s);
1390 if (comedi_get_subdevice_runflags(s) & SRF_USER)
1391 wake_up_interruptible(&s->async->wait_head);
1392
1393 return ret;
1394 }
1395
1396 /*
1397 COMEDI_POLL ioctl
1398 instructs driver to synchronize buffers
1399
1400 arg:
1401 subdevice number
1402
1403 reads:
1404 nothing
1405
1406 writes:
1407 nothing
1408
1409 */
do_poll_ioctl(struct comedi_device * dev,unsigned int arg,void * file)1410 static int do_poll_ioctl(struct comedi_device *dev, unsigned int arg,
1411 void *file)
1412 {
1413 struct comedi_subdevice *s;
1414
1415 if (arg >= dev->n_subdevices)
1416 return -EINVAL;
1417 s = dev->subdevices + arg;
1418
1419 if (s->lock && s->lock != file)
1420 return -EACCES;
1421
1422 if (!s->busy)
1423 return 0;
1424
1425 if (s->busy != file)
1426 return -EBUSY;
1427
1428 if (s->poll)
1429 return s->poll(dev, s);
1430
1431 return -EINVAL;
1432 }
1433
do_cancel(struct comedi_device * dev,struct comedi_subdevice * s)1434 static int do_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
1435 {
1436 int ret = 0;
1437
1438 if ((comedi_get_subdevice_runflags(s) & SRF_RUNNING) && s->cancel)
1439 ret = s->cancel(dev, s);
1440
1441 do_become_nonbusy(dev, s);
1442
1443 return ret;
1444 }
1445
1446
comedi_vm_open(struct vm_area_struct * area)1447 static void comedi_vm_open(struct vm_area_struct *area)
1448 {
1449 struct comedi_async *async;
1450 struct comedi_device *dev;
1451
1452 async = area->vm_private_data;
1453 dev = async->subdevice->device;
1454
1455 mutex_lock(&dev->mutex);
1456 async->mmap_count++;
1457 mutex_unlock(&dev->mutex);
1458 }
1459
comedi_vm_close(struct vm_area_struct * area)1460 static void comedi_vm_close(struct vm_area_struct *area)
1461 {
1462 struct comedi_async *async;
1463 struct comedi_device *dev;
1464
1465 async = area->vm_private_data;
1466 dev = async->subdevice->device;
1467
1468 mutex_lock(&dev->mutex);
1469 async->mmap_count--;
1470 mutex_unlock(&dev->mutex);
1471 }
1472
1473 static struct vm_operations_struct comedi_vm_ops = {
1474 .open = comedi_vm_open,
1475 .close = comedi_vm_close,
1476 };
1477
comedi_mmap(struct file * file,struct vm_area_struct * vma)1478 static int comedi_mmap(struct file *file, struct vm_area_struct *vma)
1479 {
1480 const unsigned minor = iminor(file->f_dentry->d_inode);
1481 struct comedi_async *async = NULL;
1482 unsigned long start = vma->vm_start;
1483 unsigned long size;
1484 int n_pages;
1485 int i;
1486 int retval;
1487 struct comedi_subdevice *s;
1488 struct comedi_device_file_info *dev_file_info;
1489 struct comedi_device *dev;
1490
1491 dev_file_info = comedi_get_device_file_info(minor);
1492 if (dev_file_info == NULL)
1493 return -ENODEV;
1494 dev = dev_file_info->device;
1495 if (dev == NULL)
1496 return -ENODEV;
1497
1498 mutex_lock(&dev->mutex);
1499 if (!dev->attached) {
1500 DPRINTK("no driver configured on comedi%i\n", dev->minor);
1501 retval = -ENODEV;
1502 goto done;
1503 }
1504 if (vma->vm_flags & VM_WRITE)
1505 s = comedi_get_write_subdevice(dev_file_info);
1506 else
1507 s = comedi_get_read_subdevice(dev_file_info);
1508
1509 if (s == NULL) {
1510 retval = -EINVAL;
1511 goto done;
1512 }
1513 async = s->async;
1514 if (async == NULL) {
1515 retval = -EINVAL;
1516 goto done;
1517 }
1518
1519 if (vma->vm_pgoff != 0) {
1520 DPRINTK("comedi: mmap() offset must be 0.\n");
1521 retval = -EINVAL;
1522 goto done;
1523 }
1524
1525 size = vma->vm_end - vma->vm_start;
1526 if (size > async->prealloc_bufsz) {
1527 retval = -EFAULT;
1528 goto done;
1529 }
1530 if (size & (~PAGE_MASK)) {
1531 retval = -EFAULT;
1532 goto done;
1533 }
1534
1535 n_pages = size >> PAGE_SHIFT;
1536 for (i = 0; i < n_pages; ++i) {
1537 if (remap_pfn_range(vma, start,
1538 page_to_pfn(virt_to_page
1539 (async->buf_page_list
1540 [i].virt_addr)), PAGE_SIZE,
1541 PAGE_SHARED)) {
1542 retval = -EAGAIN;
1543 goto done;
1544 }
1545 start += PAGE_SIZE;
1546 }
1547
1548 vma->vm_ops = &comedi_vm_ops;
1549 vma->vm_private_data = async;
1550
1551 async->mmap_count++;
1552
1553 retval = 0;
1554 done:
1555 mutex_unlock(&dev->mutex);
1556 return retval;
1557 }
1558
comedi_poll(struct file * file,poll_table * wait)1559 static unsigned int comedi_poll(struct file *file, poll_table * wait)
1560 {
1561 unsigned int mask = 0;
1562 const unsigned minor = iminor(file->f_dentry->d_inode);
1563 struct comedi_subdevice *read_subdev;
1564 struct comedi_subdevice *write_subdev;
1565 struct comedi_device_file_info *dev_file_info;
1566 struct comedi_device *dev;
1567 dev_file_info = comedi_get_device_file_info(minor);
1568
1569 if (dev_file_info == NULL)
1570 return -ENODEV;
1571 dev = dev_file_info->device;
1572 if (dev == NULL)
1573 return -ENODEV;
1574
1575 mutex_lock(&dev->mutex);
1576 if (!dev->attached) {
1577 DPRINTK("no driver configured on comedi%i\n", dev->minor);
1578 mutex_unlock(&dev->mutex);
1579 return 0;
1580 }
1581
1582 mask = 0;
1583 read_subdev = comedi_get_read_subdevice(dev_file_info);
1584 if (read_subdev && read_subdev->async) {
1585 poll_wait(file, &read_subdev->async->wait_head, wait);
1586 if (!read_subdev->busy
1587 || comedi_buf_read_n_available(read_subdev->async) > 0
1588 || !(comedi_get_subdevice_runflags(read_subdev) &
1589 SRF_RUNNING)) {
1590 mask |= POLLIN | POLLRDNORM;
1591 }
1592 }
1593 write_subdev = comedi_get_write_subdevice(dev_file_info);
1594 if (write_subdev && write_subdev->async) {
1595 poll_wait(file, &write_subdev->async->wait_head, wait);
1596 comedi_buf_write_alloc(write_subdev->async,
1597 write_subdev->async->prealloc_bufsz);
1598 if (!write_subdev->busy
1599 || !(comedi_get_subdevice_runflags(write_subdev) &
1600 SRF_RUNNING)
1601 || comedi_buf_write_n_allocated(write_subdev->async) >=
1602 bytes_per_sample(write_subdev->async->subdevice)) {
1603 mask |= POLLOUT | POLLWRNORM;
1604 }
1605 }
1606
1607 mutex_unlock(&dev->mutex);
1608 return mask;
1609 }
1610
comedi_write(struct file * file,const char __user * buf,size_t nbytes,loff_t * offset)1611 static ssize_t comedi_write(struct file *file, const char __user *buf,
1612 size_t nbytes, loff_t *offset)
1613 {
1614 struct comedi_subdevice *s;
1615 struct comedi_async *async;
1616 int n, m, count = 0, retval = 0;
1617 DECLARE_WAITQUEUE(wait, current);
1618 const unsigned minor = iminor(file->f_dentry->d_inode);
1619 struct comedi_device_file_info *dev_file_info;
1620 struct comedi_device *dev;
1621 dev_file_info = comedi_get_device_file_info(minor);
1622
1623 if (dev_file_info == NULL)
1624 return -ENODEV;
1625 dev = dev_file_info->device;
1626 if (dev == NULL)
1627 return -ENODEV;
1628
1629 if (!dev->attached) {
1630 DPRINTK("no driver configured on comedi%i\n", dev->minor);
1631 retval = -ENODEV;
1632 goto done;
1633 }
1634
1635 s = comedi_get_write_subdevice(dev_file_info);
1636 if (s == NULL || s->async == NULL) {
1637 retval = -EIO;
1638 goto done;
1639 }
1640 async = s->async;
1641
1642 if (!nbytes) {
1643 retval = 0;
1644 goto done;
1645 }
1646 if (!s->busy) {
1647 retval = 0;
1648 goto done;
1649 }
1650 if (s->busy != file) {
1651 retval = -EACCES;
1652 goto done;
1653 }
1654 add_wait_queue(&async->wait_head, &wait);
1655 while (nbytes > 0 && !retval) {
1656 set_current_state(TASK_INTERRUPTIBLE);
1657
1658 if (!(comedi_get_subdevice_runflags(s) & SRF_RUNNING)) {
1659 if (count == 0) {
1660 mutex_lock(&dev->mutex);
1661 if (comedi_get_subdevice_runflags(s) &
1662 SRF_ERROR) {
1663 retval = -EPIPE;
1664 } else {
1665 retval = 0;
1666 }
1667 do_become_nonbusy(dev, s);
1668 mutex_unlock(&dev->mutex);
1669 }
1670 break;
1671 }
1672
1673 n = nbytes;
1674
1675 m = n;
1676 if (async->buf_write_ptr + m > async->prealloc_bufsz)
1677 m = async->prealloc_bufsz - async->buf_write_ptr;
1678 comedi_buf_write_alloc(async, async->prealloc_bufsz);
1679 if (m > comedi_buf_write_n_allocated(async))
1680 m = comedi_buf_write_n_allocated(async);
1681 if (m < n)
1682 n = m;
1683
1684 if (n == 0) {
1685 if (file->f_flags & O_NONBLOCK) {
1686 retval = -EAGAIN;
1687 break;
1688 }
1689 schedule();
1690 if (signal_pending(current)) {
1691 retval = -ERESTARTSYS;
1692 break;
1693 }
1694 if (!s->busy)
1695 break;
1696 if (s->busy != file) {
1697 retval = -EACCES;
1698 break;
1699 }
1700 continue;
1701 }
1702
1703 m = copy_from_user(async->prealloc_buf + async->buf_write_ptr,
1704 buf, n);
1705 if (m) {
1706 n -= m;
1707 retval = -EFAULT;
1708 }
1709 comedi_buf_write_free(async, n);
1710
1711 count += n;
1712 nbytes -= n;
1713
1714 buf += n;
1715 break; /* makes device work like a pipe */
1716 }
1717 set_current_state(TASK_RUNNING);
1718 remove_wait_queue(&async->wait_head, &wait);
1719
1720 done:
1721 return count ? count : retval;
1722 }
1723
comedi_read(struct file * file,char __user * buf,size_t nbytes,loff_t * offset)1724 static ssize_t comedi_read(struct file *file, char __user *buf, size_t nbytes,
1725 loff_t *offset)
1726 {
1727 struct comedi_subdevice *s;
1728 struct comedi_async *async;
1729 int n, m, count = 0, retval = 0;
1730 DECLARE_WAITQUEUE(wait, current);
1731 const unsigned minor = iminor(file->f_dentry->d_inode);
1732 struct comedi_device_file_info *dev_file_info;
1733 struct comedi_device *dev;
1734 dev_file_info = comedi_get_device_file_info(minor);
1735
1736 if (dev_file_info == NULL)
1737 return -ENODEV;
1738 dev = dev_file_info->device;
1739 if (dev == NULL)
1740 return -ENODEV;
1741
1742 if (!dev->attached) {
1743 DPRINTK("no driver configured on comedi%i\n", dev->minor);
1744 retval = -ENODEV;
1745 goto done;
1746 }
1747
1748 s = comedi_get_read_subdevice(dev_file_info);
1749 if (s == NULL || s->async == NULL) {
1750 retval = -EIO;
1751 goto done;
1752 }
1753 async = s->async;
1754 if (!nbytes) {
1755 retval = 0;
1756 goto done;
1757 }
1758 if (!s->busy) {
1759 retval = 0;
1760 goto done;
1761 }
1762 if (s->busy != file) {
1763 retval = -EACCES;
1764 goto done;
1765 }
1766
1767 add_wait_queue(&async->wait_head, &wait);
1768 while (nbytes > 0 && !retval) {
1769 set_current_state(TASK_INTERRUPTIBLE);
1770
1771 n = nbytes;
1772
1773 m = comedi_buf_read_n_available(async);
1774 /* printk("%d available\n",m); */
1775 if (async->buf_read_ptr + m > async->prealloc_bufsz)
1776 m = async->prealloc_bufsz - async->buf_read_ptr;
1777 /* printk("%d contiguous\n",m); */
1778 if (m < n)
1779 n = m;
1780
1781 if (n == 0) {
1782 if (!(comedi_get_subdevice_runflags(s) & SRF_RUNNING)) {
1783 mutex_lock(&dev->mutex);
1784 do_become_nonbusy(dev, s);
1785 if (comedi_get_subdevice_runflags(s) &
1786 SRF_ERROR) {
1787 retval = -EPIPE;
1788 } else {
1789 retval = 0;
1790 }
1791 mutex_unlock(&dev->mutex);
1792 break;
1793 }
1794 if (file->f_flags & O_NONBLOCK) {
1795 retval = -EAGAIN;
1796 break;
1797 }
1798 schedule();
1799 if (signal_pending(current)) {
1800 retval = -ERESTARTSYS;
1801 break;
1802 }
1803 if (!s->busy) {
1804 retval = 0;
1805 break;
1806 }
1807 if (s->busy != file) {
1808 retval = -EACCES;
1809 break;
1810 }
1811 continue;
1812 }
1813 m = copy_to_user(buf, async->prealloc_buf +
1814 async->buf_read_ptr, n);
1815 if (m) {
1816 n -= m;
1817 retval = -EFAULT;
1818 }
1819
1820 comedi_buf_read_alloc(async, n);
1821 comedi_buf_read_free(async, n);
1822
1823 count += n;
1824 nbytes -= n;
1825
1826 buf += n;
1827 break; /* makes device work like a pipe */
1828 }
1829 if (!(comedi_get_subdevice_runflags(s) & (SRF_ERROR | SRF_RUNNING))) {
1830 mutex_lock(&dev->mutex);
1831 if (async->buf_read_count - async->buf_write_count == 0)
1832 do_become_nonbusy(dev, s);
1833 mutex_unlock(&dev->mutex);
1834 }
1835 set_current_state(TASK_RUNNING);
1836 remove_wait_queue(&async->wait_head, &wait);
1837
1838 done:
1839 return count ? count : retval;
1840 }
1841
1842 /*
1843 This function restores a subdevice to an idle state.
1844 */
do_become_nonbusy(struct comedi_device * dev,struct comedi_subdevice * s)1845 void do_become_nonbusy(struct comedi_device *dev, struct comedi_subdevice *s)
1846 {
1847 struct comedi_async *async = s->async;
1848
1849 comedi_set_subdevice_runflags(s, SRF_RUNNING, 0);
1850 if (async) {
1851 comedi_reset_async_buf(async);
1852 async->inttrig = NULL;
1853 kfree(async->cmd.chanlist);
1854 async->cmd.chanlist = NULL;
1855 } else {
1856 printk(KERN_ERR
1857 "BUG: (?) do_become_nonbusy called with async=0\n");
1858 }
1859
1860 s->busy = NULL;
1861 }
1862
comedi_open(struct inode * inode,struct file * file)1863 static int comedi_open(struct inode *inode, struct file *file)
1864 {
1865 const unsigned minor = iminor(inode);
1866 struct comedi_device_file_info *dev_file_info =
1867 comedi_get_device_file_info(minor);
1868 struct comedi_device *dev =
1869 dev_file_info ? dev_file_info->device : NULL;
1870
1871 if (dev == NULL) {
1872 DPRINTK("invalid minor number\n");
1873 return -ENODEV;
1874 }
1875
1876 /* This is slightly hacky, but we want module autoloading
1877 * to work for root.
1878 * case: user opens device, attached -> ok
1879 * case: user opens device, unattached, in_request_module=0 -> autoload
1880 * case: user opens device, unattached, in_request_module=1 -> fail
1881 * case: root opens device, attached -> ok
1882 * case: root opens device, unattached, in_request_module=1 -> ok
1883 * (typically called from modprobe)
1884 * case: root opens device, unattached, in_request_module=0 -> autoload
1885 *
1886 * The last could be changed to "-> ok", which would deny root
1887 * autoloading.
1888 */
1889 mutex_lock(&dev->mutex);
1890 if (dev->attached)
1891 goto ok;
1892 if (!capable(CAP_NET_ADMIN) && dev->in_request_module) {
1893 DPRINTK("in request module\n");
1894 mutex_unlock(&dev->mutex);
1895 return -ENODEV;
1896 }
1897 if (capable(CAP_NET_ADMIN) && dev->in_request_module)
1898 goto ok;
1899
1900 dev->in_request_module = 1;
1901
1902 #ifdef CONFIG_KMOD
1903 mutex_unlock(&dev->mutex);
1904 request_module("char-major-%i-%i", COMEDI_MAJOR, dev->minor);
1905 mutex_lock(&dev->mutex);
1906 #endif
1907
1908 dev->in_request_module = 0;
1909
1910 if (!dev->attached && !capable(CAP_NET_ADMIN)) {
1911 DPRINTK("not attached and not CAP_NET_ADMIN\n");
1912 mutex_unlock(&dev->mutex);
1913 return -ENODEV;
1914 }
1915 ok:
1916 __module_get(THIS_MODULE);
1917
1918 if (dev->attached) {
1919 if (!try_module_get(dev->driver->module)) {
1920 module_put(THIS_MODULE);
1921 mutex_unlock(&dev->mutex);
1922 return -ENOSYS;
1923 }
1924 }
1925
1926 if (dev->attached && dev->use_count == 0 && dev->open) {
1927 int rc = dev->open(dev);
1928 if (rc < 0) {
1929 module_put(dev->driver->module);
1930 module_put(THIS_MODULE);
1931 mutex_unlock(&dev->mutex);
1932 return rc;
1933 }
1934 }
1935
1936 dev->use_count++;
1937
1938 mutex_unlock(&dev->mutex);
1939
1940 return 0;
1941 }
1942
comedi_close(struct inode * inode,struct file * file)1943 static int comedi_close(struct inode *inode, struct file *file)
1944 {
1945 const unsigned minor = iminor(inode);
1946 struct comedi_subdevice *s = NULL;
1947 int i;
1948 struct comedi_device_file_info *dev_file_info;
1949 struct comedi_device *dev;
1950 dev_file_info = comedi_get_device_file_info(minor);
1951
1952 if (dev_file_info == NULL)
1953 return -ENODEV;
1954 dev = dev_file_info->device;
1955 if (dev == NULL)
1956 return -ENODEV;
1957
1958 mutex_lock(&dev->mutex);
1959
1960 if (dev->subdevices) {
1961 for (i = 0; i < dev->n_subdevices; i++) {
1962 s = dev->subdevices + i;
1963
1964 if (s->busy == file)
1965 do_cancel(dev, s);
1966 if (s->lock == file)
1967 s->lock = NULL;
1968 }
1969 }
1970 if (dev->attached && dev->use_count == 1 && dev->close)
1971 dev->close(dev);
1972
1973 module_put(THIS_MODULE);
1974 if (dev->attached)
1975 module_put(dev->driver->module);
1976
1977 dev->use_count--;
1978
1979 mutex_unlock(&dev->mutex);
1980
1981 if (file->f_flags & FASYNC)
1982 comedi_fasync(-1, file, 0);
1983
1984 return 0;
1985 }
1986
comedi_fasync(int fd,struct file * file,int on)1987 static int comedi_fasync(int fd, struct file *file, int on)
1988 {
1989 const unsigned minor = iminor(file->f_dentry->d_inode);
1990 struct comedi_device_file_info *dev_file_info;
1991 struct comedi_device *dev;
1992 dev_file_info = comedi_get_device_file_info(minor);
1993
1994 if (dev_file_info == NULL)
1995 return -ENODEV;
1996 dev = dev_file_info->device;
1997 if (dev == NULL)
1998 return -ENODEV;
1999
2000 return fasync_helper(fd, file, on, &dev->async_queue);
2001 }
2002
2003 const struct file_operations comedi_fops = {
2004 .owner = THIS_MODULE,
2005 .unlocked_ioctl = comedi_unlocked_ioctl,
2006 .compat_ioctl = comedi_compat_ioctl,
2007 .open = comedi_open,
2008 .release = comedi_close,
2009 .read = comedi_read,
2010 .write = comedi_write,
2011 .mmap = comedi_mmap,
2012 .poll = comedi_poll,
2013 .fasync = comedi_fasync,
2014 .llseek = noop_llseek,
2015 };
2016
2017 struct class *comedi_class;
2018 static struct cdev comedi_cdev;
2019
comedi_cleanup_legacy_minors(void)2020 static void comedi_cleanup_legacy_minors(void)
2021 {
2022 unsigned i;
2023
2024 for (i = 0; i < comedi_num_legacy_minors; i++)
2025 comedi_free_board_minor(i);
2026 }
2027
comedi_init(void)2028 static int __init comedi_init(void)
2029 {
2030 int i;
2031 int retval;
2032
2033 printk(KERN_INFO "comedi: version " COMEDI_RELEASE
2034 " - http://www.comedi.org\n");
2035
2036 if (comedi_num_legacy_minors < 0 ||
2037 comedi_num_legacy_minors > COMEDI_NUM_BOARD_MINORS) {
2038 printk(KERN_ERR "comedi: error: invalid value for module "
2039 "parameter \"comedi_num_legacy_minors\". Valid values "
2040 "are 0 through %i.\n", COMEDI_NUM_BOARD_MINORS);
2041 return -EINVAL;
2042 }
2043
2044 /*
2045 * comedi is unusable if both comedi_autoconfig and
2046 * comedi_num_legacy_minors are zero, so we might as well adjust the
2047 * defaults in that case
2048 */
2049 if (comedi_autoconfig == 0 && comedi_num_legacy_minors == 0)
2050 comedi_num_legacy_minors = 16;
2051
2052 memset(comedi_file_info_table, 0,
2053 sizeof(struct comedi_device_file_info *) * COMEDI_NUM_MINORS);
2054
2055 retval = register_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2056 COMEDI_NUM_MINORS, "comedi");
2057 if (retval)
2058 return -EIO;
2059 cdev_init(&comedi_cdev, &comedi_fops);
2060 comedi_cdev.owner = THIS_MODULE;
2061 kobject_set_name(&comedi_cdev.kobj, "comedi");
2062 if (cdev_add(&comedi_cdev, MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS)) {
2063 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2064 COMEDI_NUM_MINORS);
2065 return -EIO;
2066 }
2067 comedi_class = class_create(THIS_MODULE, "comedi");
2068 if (IS_ERR(comedi_class)) {
2069 printk(KERN_ERR "comedi: failed to create class");
2070 cdev_del(&comedi_cdev);
2071 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2072 COMEDI_NUM_MINORS);
2073 return PTR_ERR(comedi_class);
2074 }
2075
2076 /* XXX requires /proc interface */
2077 comedi_proc_init();
2078
2079 /* create devices files for legacy/manual use */
2080 for (i = 0; i < comedi_num_legacy_minors; i++) {
2081 int minor;
2082 minor = comedi_alloc_board_minor(NULL);
2083 if (minor < 0) {
2084 comedi_cleanup_legacy_minors();
2085 cdev_del(&comedi_cdev);
2086 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2087 COMEDI_NUM_MINORS);
2088 return minor;
2089 }
2090 }
2091
2092 return 0;
2093 }
2094
comedi_cleanup(void)2095 static void __exit comedi_cleanup(void)
2096 {
2097 int i;
2098
2099 comedi_cleanup_legacy_minors();
2100 for (i = 0; i < COMEDI_NUM_MINORS; ++i)
2101 BUG_ON(comedi_file_info_table[i]);
2102
2103 class_destroy(comedi_class);
2104 cdev_del(&comedi_cdev);
2105 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS);
2106
2107 comedi_proc_cleanup();
2108 }
2109
2110 module_init(comedi_init);
2111 module_exit(comedi_cleanup);
2112
comedi_error(const struct comedi_device * dev,const char * s)2113 void comedi_error(const struct comedi_device *dev, const char *s)
2114 {
2115 printk(KERN_ERR "comedi%d: %s: %s\n", dev->minor,
2116 dev->driver->driver_name, s);
2117 }
2118 EXPORT_SYMBOL(comedi_error);
2119
comedi_event(struct comedi_device * dev,struct comedi_subdevice * s)2120 void comedi_event(struct comedi_device *dev, struct comedi_subdevice *s)
2121 {
2122 struct comedi_async *async = s->async;
2123 unsigned runflags = 0;
2124 unsigned runflags_mask = 0;
2125
2126 /* DPRINTK("comedi_event 0x%x\n",mask); */
2127
2128 if ((comedi_get_subdevice_runflags(s) & SRF_RUNNING) == 0)
2129 return;
2130
2131 if (s->
2132 async->events & (COMEDI_CB_EOA | COMEDI_CB_ERROR |
2133 COMEDI_CB_OVERFLOW)) {
2134 runflags_mask |= SRF_RUNNING;
2135 }
2136 /* remember if an error event has occurred, so an error
2137 * can be returned the next time the user does a read() */
2138 if (s->async->events & (COMEDI_CB_ERROR | COMEDI_CB_OVERFLOW)) {
2139 runflags_mask |= SRF_ERROR;
2140 runflags |= SRF_ERROR;
2141 }
2142 if (runflags_mask) {
2143 /*sets SRF_ERROR and SRF_RUNNING together atomically */
2144 comedi_set_subdevice_runflags(s, runflags_mask, runflags);
2145 }
2146
2147 if (async->cb_mask & s->async->events) {
2148 if (comedi_get_subdevice_runflags(s) & SRF_USER) {
2149 wake_up_interruptible(&async->wait_head);
2150 if (s->subdev_flags & SDF_CMD_READ)
2151 kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
2152 if (s->subdev_flags & SDF_CMD_WRITE)
2153 kill_fasync(&dev->async_queue, SIGIO, POLL_OUT);
2154 } else {
2155 if (async->cb_func)
2156 async->cb_func(s->async->events, async->cb_arg);
2157 }
2158 }
2159 s->async->events = 0;
2160 }
2161 EXPORT_SYMBOL(comedi_event);
2162
comedi_get_subdevice_runflags(struct comedi_subdevice * s)2163 unsigned comedi_get_subdevice_runflags(struct comedi_subdevice *s)
2164 {
2165 unsigned long flags;
2166 unsigned runflags;
2167
2168 spin_lock_irqsave(&s->spin_lock, flags);
2169 runflags = s->runflags;
2170 spin_unlock_irqrestore(&s->spin_lock, flags);
2171 return runflags;
2172 }
2173 EXPORT_SYMBOL(comedi_get_subdevice_runflags);
2174
is_device_busy(struct comedi_device * dev)2175 static int is_device_busy(struct comedi_device *dev)
2176 {
2177 struct comedi_subdevice *s;
2178 int i;
2179
2180 if (!dev->attached)
2181 return 0;
2182
2183 for (i = 0; i < dev->n_subdevices; i++) {
2184 s = dev->subdevices + i;
2185 if (s->busy)
2186 return 1;
2187 if (s->async && s->async->mmap_count)
2188 return 1;
2189 }
2190
2191 return 0;
2192 }
2193
comedi_device_init(struct comedi_device * dev)2194 static void comedi_device_init(struct comedi_device *dev)
2195 {
2196 memset(dev, 0, sizeof(struct comedi_device));
2197 spin_lock_init(&dev->spinlock);
2198 mutex_init(&dev->mutex);
2199 dev->minor = -1;
2200 }
2201
comedi_device_cleanup(struct comedi_device * dev)2202 static void comedi_device_cleanup(struct comedi_device *dev)
2203 {
2204 if (dev == NULL)
2205 return;
2206 mutex_lock(&dev->mutex);
2207 comedi_device_detach(dev);
2208 mutex_unlock(&dev->mutex);
2209 mutex_destroy(&dev->mutex);
2210 }
2211
comedi_alloc_board_minor(struct device * hardware_device)2212 int comedi_alloc_board_minor(struct device *hardware_device)
2213 {
2214 unsigned long flags;
2215 struct comedi_device_file_info *info;
2216 struct device *csdev;
2217 unsigned i;
2218 int retval;
2219
2220 info = kzalloc(sizeof(struct comedi_device_file_info), GFP_KERNEL);
2221 if (info == NULL)
2222 return -ENOMEM;
2223 info->device = kzalloc(sizeof(struct comedi_device), GFP_KERNEL);
2224 if (info->device == NULL) {
2225 kfree(info);
2226 return -ENOMEM;
2227 }
2228 info->hardware_device = hardware_device;
2229 comedi_device_init(info->device);
2230 spin_lock_irqsave(&comedi_file_info_table_lock, flags);
2231 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; ++i) {
2232 if (comedi_file_info_table[i] == NULL) {
2233 comedi_file_info_table[i] = info;
2234 break;
2235 }
2236 }
2237 spin_unlock_irqrestore(&comedi_file_info_table_lock, flags);
2238 if (i == COMEDI_NUM_BOARD_MINORS) {
2239 comedi_device_cleanup(info->device);
2240 kfree(info->device);
2241 kfree(info);
2242 printk(KERN_ERR
2243 "comedi: error: "
2244 "ran out of minor numbers for board device files.\n");
2245 return -EBUSY;
2246 }
2247 info->device->minor = i;
2248 csdev = device_create(comedi_class, hardware_device,
2249 MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i", i);
2250 if (!IS_ERR(csdev))
2251 info->device->class_dev = csdev;
2252 dev_set_drvdata(csdev, info);
2253 retval = device_create_file(csdev, &dev_attr_max_read_buffer_kb);
2254 if (retval) {
2255 printk(KERN_ERR
2256 "comedi: "
2257 "failed to create sysfs attribute file \"%s\".\n",
2258 dev_attr_max_read_buffer_kb.attr.name);
2259 comedi_free_board_minor(i);
2260 return retval;
2261 }
2262 retval = device_create_file(csdev, &dev_attr_read_buffer_kb);
2263 if (retval) {
2264 printk(KERN_ERR
2265 "comedi: "
2266 "failed to create sysfs attribute file \"%s\".\n",
2267 dev_attr_read_buffer_kb.attr.name);
2268 comedi_free_board_minor(i);
2269 return retval;
2270 }
2271 retval = device_create_file(csdev, &dev_attr_max_write_buffer_kb);
2272 if (retval) {
2273 printk(KERN_ERR
2274 "comedi: "
2275 "failed to create sysfs attribute file \"%s\".\n",
2276 dev_attr_max_write_buffer_kb.attr.name);
2277 comedi_free_board_minor(i);
2278 return retval;
2279 }
2280 retval = device_create_file(csdev, &dev_attr_write_buffer_kb);
2281 if (retval) {
2282 printk(KERN_ERR
2283 "comedi: "
2284 "failed to create sysfs attribute file \"%s\".\n",
2285 dev_attr_write_buffer_kb.attr.name);
2286 comedi_free_board_minor(i);
2287 return retval;
2288 }
2289 return i;
2290 }
2291
comedi_free_board_minor(unsigned minor)2292 void comedi_free_board_minor(unsigned minor)
2293 {
2294 unsigned long flags;
2295 struct comedi_device_file_info *info;
2296
2297 BUG_ON(minor >= COMEDI_NUM_BOARD_MINORS);
2298 spin_lock_irqsave(&comedi_file_info_table_lock, flags);
2299 info = comedi_file_info_table[minor];
2300 comedi_file_info_table[minor] = NULL;
2301 spin_unlock_irqrestore(&comedi_file_info_table_lock, flags);
2302
2303 if (info) {
2304 struct comedi_device *dev = info->device;
2305 if (dev) {
2306 if (dev->class_dev) {
2307 device_destroy(comedi_class,
2308 MKDEV(COMEDI_MAJOR, dev->minor));
2309 }
2310 comedi_device_cleanup(dev);
2311 kfree(dev);
2312 }
2313 kfree(info);
2314 }
2315 }
2316
comedi_find_board_minor(struct device * hardware_device)2317 int comedi_find_board_minor(struct device *hardware_device)
2318 {
2319 int minor;
2320 struct comedi_device_file_info *info;
2321
2322 for (minor = 0; minor < COMEDI_NUM_BOARD_MINORS; minor++) {
2323 spin_lock(&comedi_file_info_table_lock);
2324 info = comedi_file_info_table[minor];
2325 if (info && info->hardware_device == hardware_device) {
2326 spin_unlock(&comedi_file_info_table_lock);
2327 return minor;
2328 }
2329 spin_unlock(&comedi_file_info_table_lock);
2330 }
2331 return -ENODEV;
2332 }
2333
comedi_alloc_subdevice_minor(struct comedi_device * dev,struct comedi_subdevice * s)2334 int comedi_alloc_subdevice_minor(struct comedi_device *dev,
2335 struct comedi_subdevice *s)
2336 {
2337 unsigned long flags;
2338 struct comedi_device_file_info *info;
2339 struct device *csdev;
2340 unsigned i;
2341 int retval;
2342
2343 info = kmalloc(sizeof(struct comedi_device_file_info), GFP_KERNEL);
2344 if (info == NULL)
2345 return -ENOMEM;
2346 info->device = dev;
2347 info->read_subdevice = s;
2348 info->write_subdevice = s;
2349 spin_lock_irqsave(&comedi_file_info_table_lock, flags);
2350 for (i = COMEDI_FIRST_SUBDEVICE_MINOR; i < COMEDI_NUM_MINORS; ++i) {
2351 if (comedi_file_info_table[i] == NULL) {
2352 comedi_file_info_table[i] = info;
2353 break;
2354 }
2355 }
2356 spin_unlock_irqrestore(&comedi_file_info_table_lock, flags);
2357 if (i == COMEDI_NUM_MINORS) {
2358 kfree(info);
2359 printk(KERN_ERR
2360 "comedi: error: "
2361 "ran out of minor numbers for board device files.\n");
2362 return -EBUSY;
2363 }
2364 s->minor = i;
2365 csdev = device_create(comedi_class, dev->class_dev,
2366 MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i_subd%i",
2367 dev->minor, (int)(s - dev->subdevices));
2368 if (!IS_ERR(csdev))
2369 s->class_dev = csdev;
2370 dev_set_drvdata(csdev, info);
2371 retval = device_create_file(csdev, &dev_attr_max_read_buffer_kb);
2372 if (retval) {
2373 printk(KERN_ERR
2374 "comedi: "
2375 "failed to create sysfs attribute file \"%s\".\n",
2376 dev_attr_max_read_buffer_kb.attr.name);
2377 comedi_free_subdevice_minor(s);
2378 return retval;
2379 }
2380 retval = device_create_file(csdev, &dev_attr_read_buffer_kb);
2381 if (retval) {
2382 printk(KERN_ERR
2383 "comedi: "
2384 "failed to create sysfs attribute file \"%s\".\n",
2385 dev_attr_read_buffer_kb.attr.name);
2386 comedi_free_subdevice_minor(s);
2387 return retval;
2388 }
2389 retval = device_create_file(csdev, &dev_attr_max_write_buffer_kb);
2390 if (retval) {
2391 printk(KERN_ERR
2392 "comedi: "
2393 "failed to create sysfs attribute file \"%s\".\n",
2394 dev_attr_max_write_buffer_kb.attr.name);
2395 comedi_free_subdevice_minor(s);
2396 return retval;
2397 }
2398 retval = device_create_file(csdev, &dev_attr_write_buffer_kb);
2399 if (retval) {
2400 printk(KERN_ERR
2401 "comedi: "
2402 "failed to create sysfs attribute file \"%s\".\n",
2403 dev_attr_write_buffer_kb.attr.name);
2404 comedi_free_subdevice_minor(s);
2405 return retval;
2406 }
2407 return i;
2408 }
2409
comedi_free_subdevice_minor(struct comedi_subdevice * s)2410 void comedi_free_subdevice_minor(struct comedi_subdevice *s)
2411 {
2412 unsigned long flags;
2413 struct comedi_device_file_info *info;
2414
2415 if (s == NULL)
2416 return;
2417 if (s->minor < 0)
2418 return;
2419
2420 BUG_ON(s->minor >= COMEDI_NUM_MINORS);
2421 BUG_ON(s->minor < COMEDI_FIRST_SUBDEVICE_MINOR);
2422
2423 spin_lock_irqsave(&comedi_file_info_table_lock, flags);
2424 info = comedi_file_info_table[s->minor];
2425 comedi_file_info_table[s->minor] = NULL;
2426 spin_unlock_irqrestore(&comedi_file_info_table_lock, flags);
2427
2428 if (s->class_dev) {
2429 device_destroy(comedi_class, MKDEV(COMEDI_MAJOR, s->minor));
2430 s->class_dev = NULL;
2431 }
2432 kfree(info);
2433 }
2434
comedi_get_device_file_info(unsigned minor)2435 struct comedi_device_file_info *comedi_get_device_file_info(unsigned minor)
2436 {
2437 unsigned long flags;
2438 struct comedi_device_file_info *info;
2439
2440 BUG_ON(minor >= COMEDI_NUM_MINORS);
2441 spin_lock_irqsave(&comedi_file_info_table_lock, flags);
2442 info = comedi_file_info_table[minor];
2443 spin_unlock_irqrestore(&comedi_file_info_table_lock, flags);
2444 return info;
2445 }
2446 EXPORT_SYMBOL_GPL(comedi_get_device_file_info);
2447
resize_async_buffer(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_async * async,unsigned new_size)2448 static int resize_async_buffer(struct comedi_device *dev,
2449 struct comedi_subdevice *s,
2450 struct comedi_async *async, unsigned new_size)
2451 {
2452 int retval;
2453
2454 if (new_size > async->max_bufsize)
2455 return -EPERM;
2456
2457 if (s->busy) {
2458 DPRINTK("subdevice is busy, cannot resize buffer\n");
2459 return -EBUSY;
2460 }
2461 if (async->mmap_count) {
2462 DPRINTK("subdevice is mmapped, cannot resize buffer\n");
2463 return -EBUSY;
2464 }
2465
2466 if (!async->prealloc_buf)
2467 return -EINVAL;
2468
2469 /* make sure buffer is an integral number of pages
2470 * (we round up) */
2471 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK;
2472
2473 retval = comedi_buf_alloc(dev, s, new_size);
2474 if (retval < 0)
2475 return retval;
2476
2477 if (s->buf_change) {
2478 retval = s->buf_change(dev, s, new_size);
2479 if (retval < 0)
2480 return retval;
2481 }
2482
2483 DPRINTK("comedi%i subd %d buffer resized to %i bytes\n",
2484 dev->minor, (int)(s - dev->subdevices), async->prealloc_bufsz);
2485 return 0;
2486 }
2487
2488 /* sysfs attribute files */
2489
2490 static const unsigned bytes_per_kibi = 1024;
2491
show_max_read_buffer_kb(struct device * dev,struct device_attribute * attr,char * buf)2492 static ssize_t show_max_read_buffer_kb(struct device *dev,
2493 struct device_attribute *attr, char *buf)
2494 {
2495 ssize_t retval;
2496 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2497 unsigned max_buffer_size_kb = 0;
2498 struct comedi_subdevice *const read_subdevice =
2499 comedi_get_read_subdevice(info);
2500
2501 mutex_lock(&info->device->mutex);
2502 if (read_subdevice &&
2503 (read_subdevice->subdev_flags & SDF_CMD_READ) &&
2504 read_subdevice->async) {
2505 max_buffer_size_kb = read_subdevice->async->max_bufsize /
2506 bytes_per_kibi;
2507 }
2508 retval = snprintf(buf, PAGE_SIZE, "%i\n", max_buffer_size_kb);
2509 mutex_unlock(&info->device->mutex);
2510
2511 return retval;
2512 }
2513
store_max_read_buffer_kb(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2514 static ssize_t store_max_read_buffer_kb(struct device *dev,
2515 struct device_attribute *attr,
2516 const char *buf, size_t count)
2517 {
2518 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2519 unsigned int new_max_size_kb;
2520 unsigned int new_max_size;
2521 int ret;
2522 struct comedi_subdevice *const read_subdevice =
2523 comedi_get_read_subdevice(info);
2524
2525 ret = kstrtouint(buf, 10, &new_max_size_kb);
2526 if (ret)
2527 return ret;
2528 if (new_max_size_kb > (UINT_MAX / bytes_per_kibi))
2529 return -EINVAL;
2530 new_max_size = new_max_size_kb * bytes_per_kibi;
2531
2532 mutex_lock(&info->device->mutex);
2533 if (read_subdevice == NULL ||
2534 (read_subdevice->subdev_flags & SDF_CMD_READ) == 0 ||
2535 read_subdevice->async == NULL) {
2536 mutex_unlock(&info->device->mutex);
2537 return -EINVAL;
2538 }
2539 read_subdevice->async->max_bufsize = new_max_size;
2540 mutex_unlock(&info->device->mutex);
2541
2542 return count;
2543 }
2544
2545 static struct device_attribute dev_attr_max_read_buffer_kb = {
2546 .attr = {
2547 .name = "max_read_buffer_kb",
2548 .mode = S_IRUGO | S_IWUSR},
2549 .show = &show_max_read_buffer_kb,
2550 .store = &store_max_read_buffer_kb
2551 };
2552
show_read_buffer_kb(struct device * dev,struct device_attribute * attr,char * buf)2553 static ssize_t show_read_buffer_kb(struct device *dev,
2554 struct device_attribute *attr, char *buf)
2555 {
2556 ssize_t retval;
2557 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2558 unsigned buffer_size_kb = 0;
2559 struct comedi_subdevice *const read_subdevice =
2560 comedi_get_read_subdevice(info);
2561
2562 mutex_lock(&info->device->mutex);
2563 if (read_subdevice &&
2564 (read_subdevice->subdev_flags & SDF_CMD_READ) &&
2565 read_subdevice->async) {
2566 buffer_size_kb = read_subdevice->async->prealloc_bufsz /
2567 bytes_per_kibi;
2568 }
2569 retval = snprintf(buf, PAGE_SIZE, "%i\n", buffer_size_kb);
2570 mutex_unlock(&info->device->mutex);
2571
2572 return retval;
2573 }
2574
store_read_buffer_kb(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2575 static ssize_t store_read_buffer_kb(struct device *dev,
2576 struct device_attribute *attr,
2577 const char *buf, size_t count)
2578 {
2579 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2580 unsigned int new_size_kb;
2581 unsigned int new_size;
2582 int retval;
2583 int ret;
2584 struct comedi_subdevice *const read_subdevice =
2585 comedi_get_read_subdevice(info);
2586
2587 ret = kstrtouint(buf, 10, &new_size_kb);
2588 if (ret)
2589 return ret;
2590 if (new_size_kb > (UINT_MAX / bytes_per_kibi))
2591 return -EINVAL;
2592 new_size = new_size_kb * bytes_per_kibi;
2593
2594 mutex_lock(&info->device->mutex);
2595 if (read_subdevice == NULL ||
2596 (read_subdevice->subdev_flags & SDF_CMD_READ) == 0 ||
2597 read_subdevice->async == NULL) {
2598 mutex_unlock(&info->device->mutex);
2599 return -EINVAL;
2600 }
2601 retval = resize_async_buffer(info->device, read_subdevice,
2602 read_subdevice->async, new_size);
2603 mutex_unlock(&info->device->mutex);
2604
2605 if (retval < 0)
2606 return retval;
2607 return count;
2608 }
2609
2610 static struct device_attribute dev_attr_read_buffer_kb = {
2611 .attr = {
2612 .name = "read_buffer_kb",
2613 .mode = S_IRUGO | S_IWUSR | S_IWGRP},
2614 .show = &show_read_buffer_kb,
2615 .store = &store_read_buffer_kb
2616 };
2617
show_max_write_buffer_kb(struct device * dev,struct device_attribute * attr,char * buf)2618 static ssize_t show_max_write_buffer_kb(struct device *dev,
2619 struct device_attribute *attr,
2620 char *buf)
2621 {
2622 ssize_t retval;
2623 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2624 unsigned max_buffer_size_kb = 0;
2625 struct comedi_subdevice *const write_subdevice =
2626 comedi_get_write_subdevice(info);
2627
2628 mutex_lock(&info->device->mutex);
2629 if (write_subdevice &&
2630 (write_subdevice->subdev_flags & SDF_CMD_WRITE) &&
2631 write_subdevice->async) {
2632 max_buffer_size_kb = write_subdevice->async->max_bufsize /
2633 bytes_per_kibi;
2634 }
2635 retval = snprintf(buf, PAGE_SIZE, "%i\n", max_buffer_size_kb);
2636 mutex_unlock(&info->device->mutex);
2637
2638 return retval;
2639 }
2640
store_max_write_buffer_kb(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2641 static ssize_t store_max_write_buffer_kb(struct device *dev,
2642 struct device_attribute *attr,
2643 const char *buf, size_t count)
2644 {
2645 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2646 unsigned int new_max_size_kb;
2647 unsigned int new_max_size;
2648 int ret;
2649 struct comedi_subdevice *const write_subdevice =
2650 comedi_get_write_subdevice(info);
2651
2652 ret = kstrtouint(buf, 10, &new_max_size_kb);
2653 if (ret)
2654 return ret;
2655 if (new_max_size_kb > (UINT_MAX / bytes_per_kibi))
2656 return -EINVAL;
2657 new_max_size = new_max_size_kb * bytes_per_kibi;
2658
2659 mutex_lock(&info->device->mutex);
2660 if (write_subdevice == NULL ||
2661 (write_subdevice->subdev_flags & SDF_CMD_WRITE) == 0 ||
2662 write_subdevice->async == NULL) {
2663 mutex_unlock(&info->device->mutex);
2664 return -EINVAL;
2665 }
2666 write_subdevice->async->max_bufsize = new_max_size;
2667 mutex_unlock(&info->device->mutex);
2668
2669 return count;
2670 }
2671
2672 static struct device_attribute dev_attr_max_write_buffer_kb = {
2673 .attr = {
2674 .name = "max_write_buffer_kb",
2675 .mode = S_IRUGO | S_IWUSR},
2676 .show = &show_max_write_buffer_kb,
2677 .store = &store_max_write_buffer_kb
2678 };
2679
show_write_buffer_kb(struct device * dev,struct device_attribute * attr,char * buf)2680 static ssize_t show_write_buffer_kb(struct device *dev,
2681 struct device_attribute *attr, char *buf)
2682 {
2683 ssize_t retval;
2684 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2685 unsigned buffer_size_kb = 0;
2686 struct comedi_subdevice *const write_subdevice =
2687 comedi_get_write_subdevice(info);
2688
2689 mutex_lock(&info->device->mutex);
2690 if (write_subdevice &&
2691 (write_subdevice->subdev_flags & SDF_CMD_WRITE) &&
2692 write_subdevice->async) {
2693 buffer_size_kb = write_subdevice->async->prealloc_bufsz /
2694 bytes_per_kibi;
2695 }
2696 retval = snprintf(buf, PAGE_SIZE, "%i\n", buffer_size_kb);
2697 mutex_unlock(&info->device->mutex);
2698
2699 return retval;
2700 }
2701
store_write_buffer_kb(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2702 static ssize_t store_write_buffer_kb(struct device *dev,
2703 struct device_attribute *attr,
2704 const char *buf, size_t count)
2705 {
2706 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2707 unsigned int new_size_kb;
2708 unsigned int new_size;
2709 int retval;
2710 int ret;
2711 struct comedi_subdevice *const write_subdevice =
2712 comedi_get_write_subdevice(info);
2713
2714 ret = kstrtouint(buf, 10, &new_size_kb);
2715 if (ret)
2716 return ret;
2717 if (new_size_kb > (UINT_MAX / bytes_per_kibi))
2718 return -EINVAL;
2719 new_size = ((uint64_t) new_size_kb) * bytes_per_kibi;
2720
2721 mutex_lock(&info->device->mutex);
2722 if (write_subdevice == NULL ||
2723 (write_subdevice->subdev_flags & SDF_CMD_WRITE) == 0 ||
2724 write_subdevice->async == NULL) {
2725 mutex_unlock(&info->device->mutex);
2726 return -EINVAL;
2727 }
2728 retval = resize_async_buffer(info->device, write_subdevice,
2729 write_subdevice->async, new_size);
2730 mutex_unlock(&info->device->mutex);
2731
2732 if (retval < 0)
2733 return retval;
2734 return count;
2735 }
2736
2737 static struct device_attribute dev_attr_write_buffer_kb = {
2738 .attr = {
2739 .name = "write_buffer_kb",
2740 .mode = S_IRUGO | S_IWUSR | S_IWGRP},
2741 .show = &show_write_buffer_kb,
2742 .store = &store_write_buffer_kb
2743 };
2744