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 s->busy = file;
1082
1083 /* make sure channel/gain list isn't too long */
1084 if (user_cmd.chanlist_len > s->len_chanlist) {
1085 DPRINTK("channel/gain list too long %u > %d\n",
1086 user_cmd.chanlist_len, s->len_chanlist);
1087 ret = -EINVAL;
1088 goto cleanup;
1089 }
1090
1091 /* make sure channel/gain list isn't too short */
1092 if (user_cmd.chanlist_len < 1) {
1093 DPRINTK("channel/gain list too short %u < 1\n",
1094 user_cmd.chanlist_len);
1095 ret = -EINVAL;
1096 goto cleanup;
1097 }
1098
1099 async->cmd = user_cmd;
1100 async->cmd.data = NULL;
1101 /* load channel/gain list */
1102 async->cmd.chanlist =
1103 kmalloc(async->cmd.chanlist_len * sizeof(int), GFP_KERNEL);
1104 if (!async->cmd.chanlist) {
1105 DPRINTK("allocation failed\n");
1106 ret = -ENOMEM;
1107 goto cleanup;
1108 }
1109
1110 if (copy_from_user(async->cmd.chanlist, user_cmd.chanlist,
1111 async->cmd.chanlist_len * sizeof(int))) {
1112 DPRINTK("fault reading chanlist\n");
1113 ret = -EFAULT;
1114 goto cleanup;
1115 }
1116
1117 /* make sure each element in channel/gain list is valid */
1118 ret = comedi_check_chanlist(s,
1119 async->cmd.chanlist_len,
1120 async->cmd.chanlist);
1121 if (ret < 0) {
1122 DPRINTK("bad chanlist\n");
1123 goto cleanup;
1124 }
1125
1126 ret = s->do_cmdtest(dev, s, &async->cmd);
1127
1128 if (async->cmd.flags & TRIG_BOGUS || ret) {
1129 DPRINTK("test returned %d\n", ret);
1130 user_cmd = async->cmd;
1131 /* restore chanlist pointer before copying back */
1132 user_cmd.chanlist = chanlist_saver;
1133 user_cmd.data = NULL;
1134 if (copy_to_user(cmd, &user_cmd, sizeof(struct comedi_cmd))) {
1135 DPRINTK("fault writing cmd\n");
1136 ret = -EFAULT;
1137 goto cleanup;
1138 }
1139 ret = -EAGAIN;
1140 goto cleanup;
1141 }
1142
1143 if (!async->prealloc_bufsz) {
1144 ret = -ENOMEM;
1145 DPRINTK("no buffer (?)\n");
1146 goto cleanup;
1147 }
1148
1149 comedi_reset_async_buf(async);
1150
1151 async->cb_mask =
1152 COMEDI_CB_EOA | COMEDI_CB_BLOCK | COMEDI_CB_ERROR |
1153 COMEDI_CB_OVERFLOW;
1154 if (async->cmd.flags & TRIG_WAKE_EOS)
1155 async->cb_mask |= COMEDI_CB_EOS;
1156
1157 comedi_set_subdevice_runflags(s, ~0, SRF_USER | SRF_RUNNING);
1158
1159 ret = s->do_cmd(dev, s);
1160 if (ret == 0)
1161 return 0;
1162
1163 cleanup:
1164 do_become_nonbusy(dev, s);
1165
1166 return ret;
1167 }
1168
1169 /*
1170 COMEDI_CMDTEST
1171 command testing ioctl
1172
1173 arg:
1174 pointer to cmd structure
1175
1176 reads:
1177 cmd structure at arg
1178 channel/range list
1179
1180 writes:
1181 modified cmd structure at arg
1182
1183 */
do_cmdtest_ioctl(struct comedi_device * dev,struct comedi_cmd __user * arg,void * file)1184 static int do_cmdtest_ioctl(struct comedi_device *dev,
1185 struct comedi_cmd __user *arg, void *file)
1186 {
1187 struct comedi_cmd user_cmd;
1188 struct comedi_subdevice *s;
1189 int ret = 0;
1190 unsigned int *chanlist = NULL;
1191 unsigned int __user *chanlist_saver = NULL;
1192
1193 if (copy_from_user(&user_cmd, arg, sizeof(struct comedi_cmd))) {
1194 DPRINTK("bad cmd address\n");
1195 return -EFAULT;
1196 }
1197 /* save user's chanlist pointer so it can be restored later */
1198 chanlist_saver = user_cmd.chanlist;
1199
1200 if (user_cmd.subdev >= dev->n_subdevices) {
1201 DPRINTK("%d no such subdevice\n", user_cmd.subdev);
1202 return -ENODEV;
1203 }
1204
1205 s = dev->subdevices + user_cmd.subdev;
1206 if (s->type == COMEDI_SUBD_UNUSED) {
1207 DPRINTK("%d not valid subdevice\n", user_cmd.subdev);
1208 return -EIO;
1209 }
1210
1211 if (!s->do_cmd || !s->do_cmdtest) {
1212 DPRINTK("subdevice %i does not support commands\n",
1213 user_cmd.subdev);
1214 return -EIO;
1215 }
1216
1217 /* make sure channel/gain list isn't too long */
1218 if (user_cmd.chanlist_len > s->len_chanlist) {
1219 DPRINTK("channel/gain list too long %d > %d\n",
1220 user_cmd.chanlist_len, s->len_chanlist);
1221 ret = -EINVAL;
1222 goto cleanup;
1223 }
1224
1225 /* load channel/gain list */
1226 if (user_cmd.chanlist) {
1227 chanlist =
1228 kmalloc(user_cmd.chanlist_len * sizeof(int), GFP_KERNEL);
1229 if (!chanlist) {
1230 DPRINTK("allocation failed\n");
1231 ret = -ENOMEM;
1232 goto cleanup;
1233 }
1234
1235 if (copy_from_user(chanlist, user_cmd.chanlist,
1236 user_cmd.chanlist_len * sizeof(int))) {
1237 DPRINTK("fault reading chanlist\n");
1238 ret = -EFAULT;
1239 goto cleanup;
1240 }
1241
1242 /* make sure each element in channel/gain list is valid */
1243 ret = comedi_check_chanlist(s, user_cmd.chanlist_len, chanlist);
1244 if (ret < 0) {
1245 DPRINTK("bad chanlist\n");
1246 goto cleanup;
1247 }
1248
1249 user_cmd.chanlist = chanlist;
1250 }
1251
1252 ret = s->do_cmdtest(dev, s, &user_cmd);
1253
1254 /* restore chanlist pointer before copying back */
1255 user_cmd.chanlist = chanlist_saver;
1256
1257 if (copy_to_user(arg, &user_cmd, sizeof(struct comedi_cmd))) {
1258 DPRINTK("bad cmd address\n");
1259 ret = -EFAULT;
1260 goto cleanup;
1261 }
1262 cleanup:
1263 kfree(chanlist);
1264
1265 return ret;
1266 }
1267
1268 /*
1269 COMEDI_LOCK
1270 lock subdevice
1271
1272 arg:
1273 subdevice number
1274
1275 reads:
1276 none
1277
1278 writes:
1279 none
1280
1281 */
1282
do_lock_ioctl(struct comedi_device * dev,unsigned int arg,void * file)1283 static int do_lock_ioctl(struct comedi_device *dev, unsigned int arg,
1284 void *file)
1285 {
1286 int ret = 0;
1287 unsigned long flags;
1288 struct comedi_subdevice *s;
1289
1290 if (arg >= dev->n_subdevices)
1291 return -EINVAL;
1292 s = dev->subdevices + arg;
1293
1294 spin_lock_irqsave(&s->spin_lock, flags);
1295 if (s->busy || s->lock)
1296 ret = -EBUSY;
1297 else
1298 s->lock = file;
1299 spin_unlock_irqrestore(&s->spin_lock, flags);
1300
1301 #if 0
1302 if (ret < 0)
1303 return ret;
1304
1305 if (s->lock_f)
1306 ret = s->lock_f(dev, s);
1307 #endif
1308
1309 return ret;
1310 }
1311
1312 /*
1313 COMEDI_UNLOCK
1314 unlock subdevice
1315
1316 arg:
1317 subdevice number
1318
1319 reads:
1320 none
1321
1322 writes:
1323 none
1324
1325 This function isn't protected by the semaphore, since
1326 we already own the lock.
1327 */
do_unlock_ioctl(struct comedi_device * dev,unsigned int arg,void * file)1328 static int do_unlock_ioctl(struct comedi_device *dev, unsigned int arg,
1329 void *file)
1330 {
1331 struct comedi_subdevice *s;
1332
1333 if (arg >= dev->n_subdevices)
1334 return -EINVAL;
1335 s = dev->subdevices + arg;
1336
1337 if (s->busy)
1338 return -EBUSY;
1339
1340 if (s->lock && s->lock != file)
1341 return -EACCES;
1342
1343 if (s->lock == file) {
1344 #if 0
1345 if (s->unlock)
1346 s->unlock(dev, s);
1347 #endif
1348
1349 s->lock = NULL;
1350 }
1351
1352 return 0;
1353 }
1354
1355 /*
1356 COMEDI_CANCEL
1357 cancel acquisition ioctl
1358
1359 arg:
1360 subdevice number
1361
1362 reads:
1363 nothing
1364
1365 writes:
1366 nothing
1367
1368 */
do_cancel_ioctl(struct comedi_device * dev,unsigned int arg,void * file)1369 static int do_cancel_ioctl(struct comedi_device *dev, unsigned int arg,
1370 void *file)
1371 {
1372 struct comedi_subdevice *s;
1373 int ret;
1374
1375 if (arg >= dev->n_subdevices)
1376 return -EINVAL;
1377 s = dev->subdevices + arg;
1378 if (s->async == NULL)
1379 return -EINVAL;
1380
1381 if (s->lock && s->lock != file)
1382 return -EACCES;
1383
1384 if (!s->busy)
1385 return 0;
1386
1387 if (s->busy != file)
1388 return -EBUSY;
1389
1390 ret = do_cancel(dev, s);
1391 if (comedi_get_subdevice_runflags(s) & SRF_USER)
1392 wake_up_interruptible(&s->async->wait_head);
1393
1394 return ret;
1395 }
1396
1397 /*
1398 COMEDI_POLL ioctl
1399 instructs driver to synchronize buffers
1400
1401 arg:
1402 subdevice number
1403
1404 reads:
1405 nothing
1406
1407 writes:
1408 nothing
1409
1410 */
do_poll_ioctl(struct comedi_device * dev,unsigned int arg,void * file)1411 static int do_poll_ioctl(struct comedi_device *dev, unsigned int arg,
1412 void *file)
1413 {
1414 struct comedi_subdevice *s;
1415
1416 if (arg >= dev->n_subdevices)
1417 return -EINVAL;
1418 s = dev->subdevices + arg;
1419
1420 if (s->lock && s->lock != file)
1421 return -EACCES;
1422
1423 if (!s->busy)
1424 return 0;
1425
1426 if (s->busy != file)
1427 return -EBUSY;
1428
1429 if (s->poll)
1430 return s->poll(dev, s);
1431
1432 return -EINVAL;
1433 }
1434
do_cancel(struct comedi_device * dev,struct comedi_subdevice * s)1435 static int do_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
1436 {
1437 int ret = 0;
1438
1439 if ((comedi_get_subdevice_runflags(s) & SRF_RUNNING) && s->cancel)
1440 ret = s->cancel(dev, s);
1441
1442 do_become_nonbusy(dev, s);
1443
1444 return ret;
1445 }
1446
1447
comedi_vm_open(struct vm_area_struct * area)1448 static void comedi_vm_open(struct vm_area_struct *area)
1449 {
1450 struct comedi_async *async;
1451 struct comedi_device *dev;
1452
1453 async = area->vm_private_data;
1454 dev = async->subdevice->device;
1455
1456 mutex_lock(&dev->mutex);
1457 async->mmap_count++;
1458 mutex_unlock(&dev->mutex);
1459 }
1460
comedi_vm_close(struct vm_area_struct * area)1461 static void comedi_vm_close(struct vm_area_struct *area)
1462 {
1463 struct comedi_async *async;
1464 struct comedi_device *dev;
1465
1466 async = area->vm_private_data;
1467 dev = async->subdevice->device;
1468
1469 mutex_lock(&dev->mutex);
1470 async->mmap_count--;
1471 mutex_unlock(&dev->mutex);
1472 }
1473
1474 static struct vm_operations_struct comedi_vm_ops = {
1475 .open = comedi_vm_open,
1476 .close = comedi_vm_close,
1477 };
1478
comedi_mmap(struct file * file,struct vm_area_struct * vma)1479 static int comedi_mmap(struct file *file, struct vm_area_struct *vma)
1480 {
1481 const unsigned minor = iminor(file->f_dentry->d_inode);
1482 struct comedi_async *async = NULL;
1483 unsigned long start = vma->vm_start;
1484 unsigned long size;
1485 int n_pages;
1486 int i;
1487 int retval;
1488 struct comedi_subdevice *s;
1489 struct comedi_device_file_info *dev_file_info;
1490 struct comedi_device *dev;
1491
1492 dev_file_info = comedi_get_device_file_info(minor);
1493 if (dev_file_info == NULL)
1494 return -ENODEV;
1495 dev = dev_file_info->device;
1496 if (dev == NULL)
1497 return -ENODEV;
1498
1499 mutex_lock(&dev->mutex);
1500 if (!dev->attached) {
1501 DPRINTK("no driver configured on comedi%i\n", dev->minor);
1502 retval = -ENODEV;
1503 goto done;
1504 }
1505 if (vma->vm_flags & VM_WRITE)
1506 s = comedi_get_write_subdevice(dev_file_info);
1507 else
1508 s = comedi_get_read_subdevice(dev_file_info);
1509
1510 if (s == NULL) {
1511 retval = -EINVAL;
1512 goto done;
1513 }
1514 async = s->async;
1515 if (async == NULL) {
1516 retval = -EINVAL;
1517 goto done;
1518 }
1519
1520 if (vma->vm_pgoff != 0) {
1521 DPRINTK("comedi: mmap() offset must be 0.\n");
1522 retval = -EINVAL;
1523 goto done;
1524 }
1525
1526 size = vma->vm_end - vma->vm_start;
1527 if (size > async->prealloc_bufsz) {
1528 retval = -EFAULT;
1529 goto done;
1530 }
1531 if (size & (~PAGE_MASK)) {
1532 retval = -EFAULT;
1533 goto done;
1534 }
1535
1536 n_pages = size >> PAGE_SHIFT;
1537 for (i = 0; i < n_pages; ++i) {
1538 if (remap_pfn_range(vma, start,
1539 page_to_pfn(virt_to_page
1540 (async->buf_page_list
1541 [i].virt_addr)), PAGE_SIZE,
1542 PAGE_SHARED)) {
1543 retval = -EAGAIN;
1544 goto done;
1545 }
1546 start += PAGE_SIZE;
1547 }
1548
1549 vma->vm_ops = &comedi_vm_ops;
1550 vma->vm_private_data = async;
1551
1552 async->mmap_count++;
1553
1554 retval = 0;
1555 done:
1556 mutex_unlock(&dev->mutex);
1557 return retval;
1558 }
1559
comedi_poll(struct file * file,poll_table * wait)1560 static unsigned int comedi_poll(struct file *file, poll_table * wait)
1561 {
1562 unsigned int mask = 0;
1563 const unsigned minor = iminor(file->f_dentry->d_inode);
1564 struct comedi_subdevice *read_subdev;
1565 struct comedi_subdevice *write_subdev;
1566 struct comedi_device_file_info *dev_file_info;
1567 struct comedi_device *dev;
1568 dev_file_info = comedi_get_device_file_info(minor);
1569
1570 if (dev_file_info == NULL)
1571 return -ENODEV;
1572 dev = dev_file_info->device;
1573 if (dev == NULL)
1574 return -ENODEV;
1575
1576 mutex_lock(&dev->mutex);
1577 if (!dev->attached) {
1578 DPRINTK("no driver configured on comedi%i\n", dev->minor);
1579 mutex_unlock(&dev->mutex);
1580 return 0;
1581 }
1582
1583 mask = 0;
1584 read_subdev = comedi_get_read_subdevice(dev_file_info);
1585 if (read_subdev && read_subdev->async) {
1586 poll_wait(file, &read_subdev->async->wait_head, wait);
1587 if (!read_subdev->busy
1588 || comedi_buf_read_n_available(read_subdev->async) > 0
1589 || !(comedi_get_subdevice_runflags(read_subdev) &
1590 SRF_RUNNING)) {
1591 mask |= POLLIN | POLLRDNORM;
1592 }
1593 }
1594 write_subdev = comedi_get_write_subdevice(dev_file_info);
1595 if (write_subdev && write_subdev->async) {
1596 poll_wait(file, &write_subdev->async->wait_head, wait);
1597 comedi_buf_write_alloc(write_subdev->async,
1598 write_subdev->async->prealloc_bufsz);
1599 if (!write_subdev->busy
1600 || !(comedi_get_subdevice_runflags(write_subdev) &
1601 SRF_RUNNING)
1602 || comedi_buf_write_n_allocated(write_subdev->async) >=
1603 bytes_per_sample(write_subdev->async->subdevice)) {
1604 mask |= POLLOUT | POLLWRNORM;
1605 }
1606 }
1607
1608 mutex_unlock(&dev->mutex);
1609 return mask;
1610 }
1611
comedi_write(struct file * file,const char __user * buf,size_t nbytes,loff_t * offset)1612 static ssize_t comedi_write(struct file *file, const char __user *buf,
1613 size_t nbytes, loff_t *offset)
1614 {
1615 struct comedi_subdevice *s;
1616 struct comedi_async *async;
1617 int n, m, count = 0, retval = 0;
1618 DECLARE_WAITQUEUE(wait, current);
1619 const unsigned minor = iminor(file->f_dentry->d_inode);
1620 struct comedi_device_file_info *dev_file_info;
1621 struct comedi_device *dev;
1622 dev_file_info = comedi_get_device_file_info(minor);
1623
1624 if (dev_file_info == NULL)
1625 return -ENODEV;
1626 dev = dev_file_info->device;
1627 if (dev == NULL)
1628 return -ENODEV;
1629
1630 if (!dev->attached) {
1631 DPRINTK("no driver configured on comedi%i\n", dev->minor);
1632 retval = -ENODEV;
1633 goto done;
1634 }
1635
1636 s = comedi_get_write_subdevice(dev_file_info);
1637 if (s == NULL || s->async == NULL) {
1638 retval = -EIO;
1639 goto done;
1640 }
1641 async = s->async;
1642
1643 if (!nbytes) {
1644 retval = 0;
1645 goto done;
1646 }
1647 if (!s->busy) {
1648 retval = 0;
1649 goto done;
1650 }
1651 if (s->busy != file) {
1652 retval = -EACCES;
1653 goto done;
1654 }
1655 add_wait_queue(&async->wait_head, &wait);
1656 while (nbytes > 0 && !retval) {
1657 set_current_state(TASK_INTERRUPTIBLE);
1658
1659 if (!(comedi_get_subdevice_runflags(s) & SRF_RUNNING)) {
1660 if (count == 0) {
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 }
1669 break;
1670 }
1671
1672 n = nbytes;
1673
1674 m = n;
1675 if (async->buf_write_ptr + m > async->prealloc_bufsz)
1676 m = async->prealloc_bufsz - async->buf_write_ptr;
1677 comedi_buf_write_alloc(async, async->prealloc_bufsz);
1678 if (m > comedi_buf_write_n_allocated(async))
1679 m = comedi_buf_write_n_allocated(async);
1680 if (m < n)
1681 n = m;
1682
1683 if (n == 0) {
1684 if (file->f_flags & O_NONBLOCK) {
1685 retval = -EAGAIN;
1686 break;
1687 }
1688 schedule();
1689 if (signal_pending(current)) {
1690 retval = -ERESTARTSYS;
1691 break;
1692 }
1693 if (!s->busy)
1694 break;
1695 if (s->busy != file) {
1696 retval = -EACCES;
1697 break;
1698 }
1699 continue;
1700 }
1701
1702 m = copy_from_user(async->prealloc_buf + async->buf_write_ptr,
1703 buf, n);
1704 if (m) {
1705 n -= m;
1706 retval = -EFAULT;
1707 }
1708 comedi_buf_write_free(async, n);
1709
1710 count += n;
1711 nbytes -= n;
1712
1713 buf += n;
1714 break; /* makes device work like a pipe */
1715 }
1716 set_current_state(TASK_RUNNING);
1717 remove_wait_queue(&async->wait_head, &wait);
1718
1719 done:
1720 return count ? count : retval;
1721 }
1722
comedi_read(struct file * file,char __user * buf,size_t nbytes,loff_t * offset)1723 static ssize_t comedi_read(struct file *file, char __user *buf, size_t nbytes,
1724 loff_t *offset)
1725 {
1726 struct comedi_subdevice *s;
1727 struct comedi_async *async;
1728 int n, m, count = 0, retval = 0;
1729 DECLARE_WAITQUEUE(wait, current);
1730 const unsigned minor = iminor(file->f_dentry->d_inode);
1731 struct comedi_device_file_info *dev_file_info;
1732 struct comedi_device *dev;
1733 dev_file_info = comedi_get_device_file_info(minor);
1734
1735 if (dev_file_info == NULL)
1736 return -ENODEV;
1737 dev = dev_file_info->device;
1738 if (dev == NULL)
1739 return -ENODEV;
1740
1741 if (!dev->attached) {
1742 DPRINTK("no driver configured on comedi%i\n", dev->minor);
1743 retval = -ENODEV;
1744 goto done;
1745 }
1746
1747 s = comedi_get_read_subdevice(dev_file_info);
1748 if (s == NULL || s->async == NULL) {
1749 retval = -EIO;
1750 goto done;
1751 }
1752 async = s->async;
1753 if (!nbytes) {
1754 retval = 0;
1755 goto done;
1756 }
1757 if (!s->busy) {
1758 retval = 0;
1759 goto done;
1760 }
1761 if (s->busy != file) {
1762 retval = -EACCES;
1763 goto done;
1764 }
1765
1766 add_wait_queue(&async->wait_head, &wait);
1767 while (nbytes > 0 && !retval) {
1768 set_current_state(TASK_INTERRUPTIBLE);
1769
1770 n = nbytes;
1771
1772 m = comedi_buf_read_n_available(async);
1773 /* printk("%d available\n",m); */
1774 if (async->buf_read_ptr + m > async->prealloc_bufsz)
1775 m = async->prealloc_bufsz - async->buf_read_ptr;
1776 /* printk("%d contiguous\n",m); */
1777 if (m < n)
1778 n = m;
1779
1780 if (n == 0) {
1781 if (!(comedi_get_subdevice_runflags(s) & SRF_RUNNING)) {
1782 do_become_nonbusy(dev, s);
1783 if (comedi_get_subdevice_runflags(s) &
1784 SRF_ERROR) {
1785 retval = -EPIPE;
1786 } else {
1787 retval = 0;
1788 }
1789 break;
1790 }
1791 if (file->f_flags & O_NONBLOCK) {
1792 retval = -EAGAIN;
1793 break;
1794 }
1795 schedule();
1796 if (signal_pending(current)) {
1797 retval = -ERESTARTSYS;
1798 break;
1799 }
1800 if (!s->busy) {
1801 retval = 0;
1802 break;
1803 }
1804 if (s->busy != file) {
1805 retval = -EACCES;
1806 break;
1807 }
1808 continue;
1809 }
1810 m = copy_to_user(buf, async->prealloc_buf +
1811 async->buf_read_ptr, n);
1812 if (m) {
1813 n -= m;
1814 retval = -EFAULT;
1815 }
1816
1817 comedi_buf_read_alloc(async, n);
1818 comedi_buf_read_free(async, n);
1819
1820 count += n;
1821 nbytes -= n;
1822
1823 buf += n;
1824 break; /* makes device work like a pipe */
1825 }
1826 if (!(comedi_get_subdevice_runflags(s) & (SRF_ERROR | SRF_RUNNING)) &&
1827 async->buf_read_count - async->buf_write_count == 0) {
1828 do_become_nonbusy(dev, s);
1829 }
1830 set_current_state(TASK_RUNNING);
1831 remove_wait_queue(&async->wait_head, &wait);
1832
1833 done:
1834 return count ? count : retval;
1835 }
1836
1837 /*
1838 This function restores a subdevice to an idle state.
1839 */
do_become_nonbusy(struct comedi_device * dev,struct comedi_subdevice * s)1840 void do_become_nonbusy(struct comedi_device *dev, struct comedi_subdevice *s)
1841 {
1842 struct comedi_async *async = s->async;
1843
1844 comedi_set_subdevice_runflags(s, SRF_RUNNING, 0);
1845 if (async) {
1846 comedi_reset_async_buf(async);
1847 async->inttrig = NULL;
1848 kfree(async->cmd.chanlist);
1849 async->cmd.chanlist = NULL;
1850 } else {
1851 printk(KERN_ERR
1852 "BUG: (?) do_become_nonbusy called with async=0\n");
1853 }
1854
1855 s->busy = NULL;
1856 }
1857
comedi_open(struct inode * inode,struct file * file)1858 static int comedi_open(struct inode *inode, struct file *file)
1859 {
1860 const unsigned minor = iminor(inode);
1861 struct comedi_device_file_info *dev_file_info =
1862 comedi_get_device_file_info(minor);
1863 struct comedi_device *dev =
1864 dev_file_info ? dev_file_info->device : NULL;
1865
1866 if (dev == NULL) {
1867 DPRINTK("invalid minor number\n");
1868 return -ENODEV;
1869 }
1870
1871 /* This is slightly hacky, but we want module autoloading
1872 * to work for root.
1873 * case: user opens device, attached -> ok
1874 * case: user opens device, unattached, in_request_module=0 -> autoload
1875 * case: user opens device, unattached, in_request_module=1 -> fail
1876 * case: root opens device, attached -> ok
1877 * case: root opens device, unattached, in_request_module=1 -> ok
1878 * (typically called from modprobe)
1879 * case: root opens device, unattached, in_request_module=0 -> autoload
1880 *
1881 * The last could be changed to "-> ok", which would deny root
1882 * autoloading.
1883 */
1884 mutex_lock(&dev->mutex);
1885 if (dev->attached)
1886 goto ok;
1887 if (!capable(CAP_NET_ADMIN) && dev->in_request_module) {
1888 DPRINTK("in request module\n");
1889 mutex_unlock(&dev->mutex);
1890 return -ENODEV;
1891 }
1892 if (capable(CAP_NET_ADMIN) && dev->in_request_module)
1893 goto ok;
1894
1895 dev->in_request_module = 1;
1896
1897 #ifdef CONFIG_KMOD
1898 mutex_unlock(&dev->mutex);
1899 request_module("char-major-%i-%i", COMEDI_MAJOR, dev->minor);
1900 mutex_lock(&dev->mutex);
1901 #endif
1902
1903 dev->in_request_module = 0;
1904
1905 if (!dev->attached && !capable(CAP_NET_ADMIN)) {
1906 DPRINTK("not attached and not CAP_NET_ADMIN\n");
1907 mutex_unlock(&dev->mutex);
1908 return -ENODEV;
1909 }
1910 ok:
1911 __module_get(THIS_MODULE);
1912
1913 if (dev->attached) {
1914 if (!try_module_get(dev->driver->module)) {
1915 module_put(THIS_MODULE);
1916 mutex_unlock(&dev->mutex);
1917 return -ENOSYS;
1918 }
1919 }
1920
1921 if (dev->attached && dev->use_count == 0 && dev->open) {
1922 int rc = dev->open(dev);
1923 if (rc < 0) {
1924 module_put(dev->driver->module);
1925 module_put(THIS_MODULE);
1926 mutex_unlock(&dev->mutex);
1927 return rc;
1928 }
1929 }
1930
1931 dev->use_count++;
1932
1933 mutex_unlock(&dev->mutex);
1934
1935 return 0;
1936 }
1937
comedi_close(struct inode * inode,struct file * file)1938 static int comedi_close(struct inode *inode, struct file *file)
1939 {
1940 const unsigned minor = iminor(inode);
1941 struct comedi_subdevice *s = NULL;
1942 int i;
1943 struct comedi_device_file_info *dev_file_info;
1944 struct comedi_device *dev;
1945 dev_file_info = comedi_get_device_file_info(minor);
1946
1947 if (dev_file_info == NULL)
1948 return -ENODEV;
1949 dev = dev_file_info->device;
1950 if (dev == NULL)
1951 return -ENODEV;
1952
1953 mutex_lock(&dev->mutex);
1954
1955 if (dev->subdevices) {
1956 for (i = 0; i < dev->n_subdevices; i++) {
1957 s = dev->subdevices + i;
1958
1959 if (s->busy == file)
1960 do_cancel(dev, s);
1961 if (s->lock == file)
1962 s->lock = NULL;
1963 }
1964 }
1965 if (dev->attached && dev->use_count == 1 && dev->close)
1966 dev->close(dev);
1967
1968 module_put(THIS_MODULE);
1969 if (dev->attached)
1970 module_put(dev->driver->module);
1971
1972 dev->use_count--;
1973
1974 mutex_unlock(&dev->mutex);
1975
1976 if (file->f_flags & FASYNC)
1977 comedi_fasync(-1, file, 0);
1978
1979 return 0;
1980 }
1981
comedi_fasync(int fd,struct file * file,int on)1982 static int comedi_fasync(int fd, struct file *file, int on)
1983 {
1984 const unsigned minor = iminor(file->f_dentry->d_inode);
1985 struct comedi_device_file_info *dev_file_info;
1986 struct comedi_device *dev;
1987 dev_file_info = comedi_get_device_file_info(minor);
1988
1989 if (dev_file_info == NULL)
1990 return -ENODEV;
1991 dev = dev_file_info->device;
1992 if (dev == NULL)
1993 return -ENODEV;
1994
1995 return fasync_helper(fd, file, on, &dev->async_queue);
1996 }
1997
1998 const struct file_operations comedi_fops = {
1999 .owner = THIS_MODULE,
2000 .unlocked_ioctl = comedi_unlocked_ioctl,
2001 .compat_ioctl = comedi_compat_ioctl,
2002 .open = comedi_open,
2003 .release = comedi_close,
2004 .read = comedi_read,
2005 .write = comedi_write,
2006 .mmap = comedi_mmap,
2007 .poll = comedi_poll,
2008 .fasync = comedi_fasync,
2009 .llseek = noop_llseek,
2010 };
2011
2012 struct class *comedi_class;
2013 static struct cdev comedi_cdev;
2014
comedi_cleanup_legacy_minors(void)2015 static void comedi_cleanup_legacy_minors(void)
2016 {
2017 unsigned i;
2018
2019 for (i = 0; i < comedi_num_legacy_minors; i++)
2020 comedi_free_board_minor(i);
2021 }
2022
comedi_init(void)2023 static int __init comedi_init(void)
2024 {
2025 int i;
2026 int retval;
2027
2028 printk(KERN_INFO "comedi: version " COMEDI_RELEASE
2029 " - http://www.comedi.org\n");
2030
2031 if (comedi_num_legacy_minors < 0 ||
2032 comedi_num_legacy_minors > COMEDI_NUM_BOARD_MINORS) {
2033 printk(KERN_ERR "comedi: error: invalid value for module "
2034 "parameter \"comedi_num_legacy_minors\". Valid values "
2035 "are 0 through %i.\n", COMEDI_NUM_BOARD_MINORS);
2036 return -EINVAL;
2037 }
2038
2039 /*
2040 * comedi is unusable if both comedi_autoconfig and
2041 * comedi_num_legacy_minors are zero, so we might as well adjust the
2042 * defaults in that case
2043 */
2044 if (comedi_autoconfig == 0 && comedi_num_legacy_minors == 0)
2045 comedi_num_legacy_minors = 16;
2046
2047 memset(comedi_file_info_table, 0,
2048 sizeof(struct comedi_device_file_info *) * COMEDI_NUM_MINORS);
2049
2050 retval = register_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2051 COMEDI_NUM_MINORS, "comedi");
2052 if (retval)
2053 return -EIO;
2054 cdev_init(&comedi_cdev, &comedi_fops);
2055 comedi_cdev.owner = THIS_MODULE;
2056 kobject_set_name(&comedi_cdev.kobj, "comedi");
2057 if (cdev_add(&comedi_cdev, MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS)) {
2058 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2059 COMEDI_NUM_MINORS);
2060 return -EIO;
2061 }
2062 comedi_class = class_create(THIS_MODULE, "comedi");
2063 if (IS_ERR(comedi_class)) {
2064 printk(KERN_ERR "comedi: failed to create class");
2065 cdev_del(&comedi_cdev);
2066 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2067 COMEDI_NUM_MINORS);
2068 return PTR_ERR(comedi_class);
2069 }
2070
2071 /* XXX requires /proc interface */
2072 comedi_proc_init();
2073
2074 /* create devices files for legacy/manual use */
2075 for (i = 0; i < comedi_num_legacy_minors; i++) {
2076 int minor;
2077 minor = comedi_alloc_board_minor(NULL);
2078 if (minor < 0) {
2079 comedi_cleanup_legacy_minors();
2080 cdev_del(&comedi_cdev);
2081 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0),
2082 COMEDI_NUM_MINORS);
2083 return minor;
2084 }
2085 }
2086
2087 return 0;
2088 }
2089
comedi_cleanup(void)2090 static void __exit comedi_cleanup(void)
2091 {
2092 int i;
2093
2094 comedi_cleanup_legacy_minors();
2095 for (i = 0; i < COMEDI_NUM_MINORS; ++i)
2096 BUG_ON(comedi_file_info_table[i]);
2097
2098 class_destroy(comedi_class);
2099 cdev_del(&comedi_cdev);
2100 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS);
2101
2102 comedi_proc_cleanup();
2103 }
2104
2105 module_init(comedi_init);
2106 module_exit(comedi_cleanup);
2107
comedi_error(const struct comedi_device * dev,const char * s)2108 void comedi_error(const struct comedi_device *dev, const char *s)
2109 {
2110 printk(KERN_ERR "comedi%d: %s: %s\n", dev->minor,
2111 dev->driver->driver_name, s);
2112 }
2113 EXPORT_SYMBOL(comedi_error);
2114
comedi_event(struct comedi_device * dev,struct comedi_subdevice * s)2115 void comedi_event(struct comedi_device *dev, struct comedi_subdevice *s)
2116 {
2117 struct comedi_async *async = s->async;
2118 unsigned runflags = 0;
2119 unsigned runflags_mask = 0;
2120
2121 /* DPRINTK("comedi_event 0x%x\n",mask); */
2122
2123 if ((comedi_get_subdevice_runflags(s) & SRF_RUNNING) == 0)
2124 return;
2125
2126 if (s->
2127 async->events & (COMEDI_CB_EOA | COMEDI_CB_ERROR |
2128 COMEDI_CB_OVERFLOW)) {
2129 runflags_mask |= SRF_RUNNING;
2130 }
2131 /* remember if an error event has occurred, so an error
2132 * can be returned the next time the user does a read() */
2133 if (s->async->events & (COMEDI_CB_ERROR | COMEDI_CB_OVERFLOW)) {
2134 runflags_mask |= SRF_ERROR;
2135 runflags |= SRF_ERROR;
2136 }
2137 if (runflags_mask) {
2138 /*sets SRF_ERROR and SRF_RUNNING together atomically */
2139 comedi_set_subdevice_runflags(s, runflags_mask, runflags);
2140 }
2141
2142 if (async->cb_mask & s->async->events) {
2143 if (comedi_get_subdevice_runflags(s) & SRF_USER) {
2144 wake_up_interruptible(&async->wait_head);
2145 if (s->subdev_flags & SDF_CMD_READ)
2146 kill_fasync(&dev->async_queue, SIGIO, POLL_IN);
2147 if (s->subdev_flags & SDF_CMD_WRITE)
2148 kill_fasync(&dev->async_queue, SIGIO, POLL_OUT);
2149 } else {
2150 if (async->cb_func)
2151 async->cb_func(s->async->events, async->cb_arg);
2152 }
2153 }
2154 s->async->events = 0;
2155 }
2156 EXPORT_SYMBOL(comedi_event);
2157
comedi_get_subdevice_runflags(struct comedi_subdevice * s)2158 unsigned comedi_get_subdevice_runflags(struct comedi_subdevice *s)
2159 {
2160 unsigned long flags;
2161 unsigned runflags;
2162
2163 spin_lock_irqsave(&s->spin_lock, flags);
2164 runflags = s->runflags;
2165 spin_unlock_irqrestore(&s->spin_lock, flags);
2166 return runflags;
2167 }
2168 EXPORT_SYMBOL(comedi_get_subdevice_runflags);
2169
is_device_busy(struct comedi_device * dev)2170 static int is_device_busy(struct comedi_device *dev)
2171 {
2172 struct comedi_subdevice *s;
2173 int i;
2174
2175 if (!dev->attached)
2176 return 0;
2177
2178 for (i = 0; i < dev->n_subdevices; i++) {
2179 s = dev->subdevices + i;
2180 if (s->busy)
2181 return 1;
2182 if (s->async && s->async->mmap_count)
2183 return 1;
2184 }
2185
2186 return 0;
2187 }
2188
comedi_device_init(struct comedi_device * dev)2189 static void comedi_device_init(struct comedi_device *dev)
2190 {
2191 memset(dev, 0, sizeof(struct comedi_device));
2192 spin_lock_init(&dev->spinlock);
2193 mutex_init(&dev->mutex);
2194 dev->minor = -1;
2195 }
2196
comedi_device_cleanup(struct comedi_device * dev)2197 static void comedi_device_cleanup(struct comedi_device *dev)
2198 {
2199 if (dev == NULL)
2200 return;
2201 mutex_lock(&dev->mutex);
2202 comedi_device_detach(dev);
2203 mutex_unlock(&dev->mutex);
2204 mutex_destroy(&dev->mutex);
2205 }
2206
comedi_alloc_board_minor(struct device * hardware_device)2207 int comedi_alloc_board_minor(struct device *hardware_device)
2208 {
2209 unsigned long flags;
2210 struct comedi_device_file_info *info;
2211 struct device *csdev;
2212 unsigned i;
2213 int retval;
2214
2215 info = kzalloc(sizeof(struct comedi_device_file_info), GFP_KERNEL);
2216 if (info == NULL)
2217 return -ENOMEM;
2218 info->device = kzalloc(sizeof(struct comedi_device), GFP_KERNEL);
2219 if (info->device == NULL) {
2220 kfree(info);
2221 return -ENOMEM;
2222 }
2223 info->hardware_device = hardware_device;
2224 comedi_device_init(info->device);
2225 spin_lock_irqsave(&comedi_file_info_table_lock, flags);
2226 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; ++i) {
2227 if (comedi_file_info_table[i] == NULL) {
2228 comedi_file_info_table[i] = info;
2229 break;
2230 }
2231 }
2232 spin_unlock_irqrestore(&comedi_file_info_table_lock, flags);
2233 if (i == COMEDI_NUM_BOARD_MINORS) {
2234 comedi_device_cleanup(info->device);
2235 kfree(info->device);
2236 kfree(info);
2237 printk(KERN_ERR
2238 "comedi: error: "
2239 "ran out of minor numbers for board device files.\n");
2240 return -EBUSY;
2241 }
2242 info->device->minor = i;
2243 csdev = device_create(comedi_class, hardware_device,
2244 MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i", i);
2245 if (!IS_ERR(csdev))
2246 info->device->class_dev = csdev;
2247 dev_set_drvdata(csdev, info);
2248 retval = device_create_file(csdev, &dev_attr_max_read_buffer_kb);
2249 if (retval) {
2250 printk(KERN_ERR
2251 "comedi: "
2252 "failed to create sysfs attribute file \"%s\".\n",
2253 dev_attr_max_read_buffer_kb.attr.name);
2254 comedi_free_board_minor(i);
2255 return retval;
2256 }
2257 retval = device_create_file(csdev, &dev_attr_read_buffer_kb);
2258 if (retval) {
2259 printk(KERN_ERR
2260 "comedi: "
2261 "failed to create sysfs attribute file \"%s\".\n",
2262 dev_attr_read_buffer_kb.attr.name);
2263 comedi_free_board_minor(i);
2264 return retval;
2265 }
2266 retval = device_create_file(csdev, &dev_attr_max_write_buffer_kb);
2267 if (retval) {
2268 printk(KERN_ERR
2269 "comedi: "
2270 "failed to create sysfs attribute file \"%s\".\n",
2271 dev_attr_max_write_buffer_kb.attr.name);
2272 comedi_free_board_minor(i);
2273 return retval;
2274 }
2275 retval = device_create_file(csdev, &dev_attr_write_buffer_kb);
2276 if (retval) {
2277 printk(KERN_ERR
2278 "comedi: "
2279 "failed to create sysfs attribute file \"%s\".\n",
2280 dev_attr_write_buffer_kb.attr.name);
2281 comedi_free_board_minor(i);
2282 return retval;
2283 }
2284 return i;
2285 }
2286
comedi_free_board_minor(unsigned minor)2287 void comedi_free_board_minor(unsigned minor)
2288 {
2289 unsigned long flags;
2290 struct comedi_device_file_info *info;
2291
2292 BUG_ON(minor >= COMEDI_NUM_BOARD_MINORS);
2293 spin_lock_irqsave(&comedi_file_info_table_lock, flags);
2294 info = comedi_file_info_table[minor];
2295 comedi_file_info_table[minor] = NULL;
2296 spin_unlock_irqrestore(&comedi_file_info_table_lock, flags);
2297
2298 if (info) {
2299 struct comedi_device *dev = info->device;
2300 if (dev) {
2301 if (dev->class_dev) {
2302 device_destroy(comedi_class,
2303 MKDEV(COMEDI_MAJOR, dev->minor));
2304 }
2305 comedi_device_cleanup(dev);
2306 kfree(dev);
2307 }
2308 kfree(info);
2309 }
2310 }
2311
comedi_find_board_minor(struct device * hardware_device)2312 int comedi_find_board_minor(struct device *hardware_device)
2313 {
2314 int minor;
2315 struct comedi_device_file_info *info;
2316
2317 for (minor = 0; minor < COMEDI_NUM_BOARD_MINORS; minor++) {
2318 spin_lock(&comedi_file_info_table_lock);
2319 info = comedi_file_info_table[minor];
2320 if (info && info->hardware_device == hardware_device) {
2321 spin_unlock(&comedi_file_info_table_lock);
2322 return minor;
2323 }
2324 spin_unlock(&comedi_file_info_table_lock);
2325 }
2326 return -ENODEV;
2327 }
2328
comedi_alloc_subdevice_minor(struct comedi_device * dev,struct comedi_subdevice * s)2329 int comedi_alloc_subdevice_minor(struct comedi_device *dev,
2330 struct comedi_subdevice *s)
2331 {
2332 unsigned long flags;
2333 struct comedi_device_file_info *info;
2334 struct device *csdev;
2335 unsigned i;
2336 int retval;
2337
2338 info = kmalloc(sizeof(struct comedi_device_file_info), GFP_KERNEL);
2339 if (info == NULL)
2340 return -ENOMEM;
2341 info->device = dev;
2342 info->read_subdevice = s;
2343 info->write_subdevice = s;
2344 spin_lock_irqsave(&comedi_file_info_table_lock, flags);
2345 for (i = COMEDI_FIRST_SUBDEVICE_MINOR; i < COMEDI_NUM_MINORS; ++i) {
2346 if (comedi_file_info_table[i] == NULL) {
2347 comedi_file_info_table[i] = info;
2348 break;
2349 }
2350 }
2351 spin_unlock_irqrestore(&comedi_file_info_table_lock, flags);
2352 if (i == COMEDI_NUM_MINORS) {
2353 kfree(info);
2354 printk(KERN_ERR
2355 "comedi: error: "
2356 "ran out of minor numbers for board device files.\n");
2357 return -EBUSY;
2358 }
2359 s->minor = i;
2360 csdev = device_create(comedi_class, dev->class_dev,
2361 MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i_subd%i",
2362 dev->minor, (int)(s - dev->subdevices));
2363 if (!IS_ERR(csdev))
2364 s->class_dev = csdev;
2365 dev_set_drvdata(csdev, info);
2366 retval = device_create_file(csdev, &dev_attr_max_read_buffer_kb);
2367 if (retval) {
2368 printk(KERN_ERR
2369 "comedi: "
2370 "failed to create sysfs attribute file \"%s\".\n",
2371 dev_attr_max_read_buffer_kb.attr.name);
2372 comedi_free_subdevice_minor(s);
2373 return retval;
2374 }
2375 retval = device_create_file(csdev, &dev_attr_read_buffer_kb);
2376 if (retval) {
2377 printk(KERN_ERR
2378 "comedi: "
2379 "failed to create sysfs attribute file \"%s\".\n",
2380 dev_attr_read_buffer_kb.attr.name);
2381 comedi_free_subdevice_minor(s);
2382 return retval;
2383 }
2384 retval = device_create_file(csdev, &dev_attr_max_write_buffer_kb);
2385 if (retval) {
2386 printk(KERN_ERR
2387 "comedi: "
2388 "failed to create sysfs attribute file \"%s\".\n",
2389 dev_attr_max_write_buffer_kb.attr.name);
2390 comedi_free_subdevice_minor(s);
2391 return retval;
2392 }
2393 retval = device_create_file(csdev, &dev_attr_write_buffer_kb);
2394 if (retval) {
2395 printk(KERN_ERR
2396 "comedi: "
2397 "failed to create sysfs attribute file \"%s\".\n",
2398 dev_attr_write_buffer_kb.attr.name);
2399 comedi_free_subdevice_minor(s);
2400 return retval;
2401 }
2402 return i;
2403 }
2404
comedi_free_subdevice_minor(struct comedi_subdevice * s)2405 void comedi_free_subdevice_minor(struct comedi_subdevice *s)
2406 {
2407 unsigned long flags;
2408 struct comedi_device_file_info *info;
2409
2410 if (s == NULL)
2411 return;
2412 if (s->minor < 0)
2413 return;
2414
2415 BUG_ON(s->minor >= COMEDI_NUM_MINORS);
2416 BUG_ON(s->minor < COMEDI_FIRST_SUBDEVICE_MINOR);
2417
2418 spin_lock_irqsave(&comedi_file_info_table_lock, flags);
2419 info = comedi_file_info_table[s->minor];
2420 comedi_file_info_table[s->minor] = NULL;
2421 spin_unlock_irqrestore(&comedi_file_info_table_lock, flags);
2422
2423 if (s->class_dev) {
2424 device_destroy(comedi_class, MKDEV(COMEDI_MAJOR, s->minor));
2425 s->class_dev = NULL;
2426 }
2427 kfree(info);
2428 }
2429
comedi_get_device_file_info(unsigned minor)2430 struct comedi_device_file_info *comedi_get_device_file_info(unsigned minor)
2431 {
2432 unsigned long flags;
2433 struct comedi_device_file_info *info;
2434
2435 BUG_ON(minor >= COMEDI_NUM_MINORS);
2436 spin_lock_irqsave(&comedi_file_info_table_lock, flags);
2437 info = comedi_file_info_table[minor];
2438 spin_unlock_irqrestore(&comedi_file_info_table_lock, flags);
2439 return info;
2440 }
2441 EXPORT_SYMBOL_GPL(comedi_get_device_file_info);
2442
resize_async_buffer(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_async * async,unsigned new_size)2443 static int resize_async_buffer(struct comedi_device *dev,
2444 struct comedi_subdevice *s,
2445 struct comedi_async *async, unsigned new_size)
2446 {
2447 int retval;
2448
2449 if (new_size > async->max_bufsize)
2450 return -EPERM;
2451
2452 if (s->busy) {
2453 DPRINTK("subdevice is busy, cannot resize buffer\n");
2454 return -EBUSY;
2455 }
2456 if (async->mmap_count) {
2457 DPRINTK("subdevice is mmapped, cannot resize buffer\n");
2458 return -EBUSY;
2459 }
2460
2461 if (!async->prealloc_buf)
2462 return -EINVAL;
2463
2464 /* make sure buffer is an integral number of pages
2465 * (we round up) */
2466 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK;
2467
2468 retval = comedi_buf_alloc(dev, s, new_size);
2469 if (retval < 0)
2470 return retval;
2471
2472 if (s->buf_change) {
2473 retval = s->buf_change(dev, s, new_size);
2474 if (retval < 0)
2475 return retval;
2476 }
2477
2478 DPRINTK("comedi%i subd %d buffer resized to %i bytes\n",
2479 dev->minor, (int)(s - dev->subdevices), async->prealloc_bufsz);
2480 return 0;
2481 }
2482
2483 /* sysfs attribute files */
2484
2485 static const unsigned bytes_per_kibi = 1024;
2486
show_max_read_buffer_kb(struct device * dev,struct device_attribute * attr,char * buf)2487 static ssize_t show_max_read_buffer_kb(struct device *dev,
2488 struct device_attribute *attr, char *buf)
2489 {
2490 ssize_t retval;
2491 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2492 unsigned max_buffer_size_kb = 0;
2493 struct comedi_subdevice *const read_subdevice =
2494 comedi_get_read_subdevice(info);
2495
2496 mutex_lock(&info->device->mutex);
2497 if (read_subdevice &&
2498 (read_subdevice->subdev_flags & SDF_CMD_READ) &&
2499 read_subdevice->async) {
2500 max_buffer_size_kb = read_subdevice->async->max_bufsize /
2501 bytes_per_kibi;
2502 }
2503 retval = snprintf(buf, PAGE_SIZE, "%i\n", max_buffer_size_kb);
2504 mutex_unlock(&info->device->mutex);
2505
2506 return retval;
2507 }
2508
store_max_read_buffer_kb(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2509 static ssize_t store_max_read_buffer_kb(struct device *dev,
2510 struct device_attribute *attr,
2511 const char *buf, size_t count)
2512 {
2513 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2514 unsigned int new_max_size_kb;
2515 unsigned int new_max_size;
2516 int ret;
2517 struct comedi_subdevice *const read_subdevice =
2518 comedi_get_read_subdevice(info);
2519
2520 ret = kstrtouint(buf, 10, &new_max_size_kb);
2521 if (ret)
2522 return ret;
2523 if (new_max_size_kb > (UINT_MAX / bytes_per_kibi))
2524 return -EINVAL;
2525 new_max_size = new_max_size_kb * bytes_per_kibi;
2526
2527 mutex_lock(&info->device->mutex);
2528 if (read_subdevice == NULL ||
2529 (read_subdevice->subdev_flags & SDF_CMD_READ) == 0 ||
2530 read_subdevice->async == NULL) {
2531 mutex_unlock(&info->device->mutex);
2532 return -EINVAL;
2533 }
2534 read_subdevice->async->max_bufsize = new_max_size;
2535 mutex_unlock(&info->device->mutex);
2536
2537 return count;
2538 }
2539
2540 static struct device_attribute dev_attr_max_read_buffer_kb = {
2541 .attr = {
2542 .name = "max_read_buffer_kb",
2543 .mode = S_IRUGO | S_IWUSR},
2544 .show = &show_max_read_buffer_kb,
2545 .store = &store_max_read_buffer_kb
2546 };
2547
show_read_buffer_kb(struct device * dev,struct device_attribute * attr,char * buf)2548 static ssize_t show_read_buffer_kb(struct device *dev,
2549 struct device_attribute *attr, char *buf)
2550 {
2551 ssize_t retval;
2552 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2553 unsigned buffer_size_kb = 0;
2554 struct comedi_subdevice *const read_subdevice =
2555 comedi_get_read_subdevice(info);
2556
2557 mutex_lock(&info->device->mutex);
2558 if (read_subdevice &&
2559 (read_subdevice->subdev_flags & SDF_CMD_READ) &&
2560 read_subdevice->async) {
2561 buffer_size_kb = read_subdevice->async->prealloc_bufsz /
2562 bytes_per_kibi;
2563 }
2564 retval = snprintf(buf, PAGE_SIZE, "%i\n", buffer_size_kb);
2565 mutex_unlock(&info->device->mutex);
2566
2567 return retval;
2568 }
2569
store_read_buffer_kb(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2570 static ssize_t store_read_buffer_kb(struct device *dev,
2571 struct device_attribute *attr,
2572 const char *buf, size_t count)
2573 {
2574 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2575 unsigned int new_size_kb;
2576 unsigned int new_size;
2577 int retval;
2578 int ret;
2579 struct comedi_subdevice *const read_subdevice =
2580 comedi_get_read_subdevice(info);
2581
2582 ret = kstrtouint(buf, 10, &new_size_kb);
2583 if (ret)
2584 return ret;
2585 if (new_size_kb > (UINT_MAX / bytes_per_kibi))
2586 return -EINVAL;
2587 new_size = new_size_kb * bytes_per_kibi;
2588
2589 mutex_lock(&info->device->mutex);
2590 if (read_subdevice == NULL ||
2591 (read_subdevice->subdev_flags & SDF_CMD_READ) == 0 ||
2592 read_subdevice->async == NULL) {
2593 mutex_unlock(&info->device->mutex);
2594 return -EINVAL;
2595 }
2596 retval = resize_async_buffer(info->device, read_subdevice,
2597 read_subdevice->async, new_size);
2598 mutex_unlock(&info->device->mutex);
2599
2600 if (retval < 0)
2601 return retval;
2602 return count;
2603 }
2604
2605 static struct device_attribute dev_attr_read_buffer_kb = {
2606 .attr = {
2607 .name = "read_buffer_kb",
2608 .mode = S_IRUGO | S_IWUSR | S_IWGRP},
2609 .show = &show_read_buffer_kb,
2610 .store = &store_read_buffer_kb
2611 };
2612
show_max_write_buffer_kb(struct device * dev,struct device_attribute * attr,char * buf)2613 static ssize_t show_max_write_buffer_kb(struct device *dev,
2614 struct device_attribute *attr,
2615 char *buf)
2616 {
2617 ssize_t retval;
2618 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2619 unsigned max_buffer_size_kb = 0;
2620 struct comedi_subdevice *const write_subdevice =
2621 comedi_get_write_subdevice(info);
2622
2623 mutex_lock(&info->device->mutex);
2624 if (write_subdevice &&
2625 (write_subdevice->subdev_flags & SDF_CMD_WRITE) &&
2626 write_subdevice->async) {
2627 max_buffer_size_kb = write_subdevice->async->max_bufsize /
2628 bytes_per_kibi;
2629 }
2630 retval = snprintf(buf, PAGE_SIZE, "%i\n", max_buffer_size_kb);
2631 mutex_unlock(&info->device->mutex);
2632
2633 return retval;
2634 }
2635
store_max_write_buffer_kb(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2636 static ssize_t store_max_write_buffer_kb(struct device *dev,
2637 struct device_attribute *attr,
2638 const char *buf, size_t count)
2639 {
2640 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2641 unsigned int new_max_size_kb;
2642 unsigned int new_max_size;
2643 int ret;
2644 struct comedi_subdevice *const write_subdevice =
2645 comedi_get_write_subdevice(info);
2646
2647 ret = kstrtouint(buf, 10, &new_max_size_kb);
2648 if (ret)
2649 return ret;
2650 if (new_max_size_kb > (UINT_MAX / bytes_per_kibi))
2651 return -EINVAL;
2652 new_max_size = new_max_size_kb * bytes_per_kibi;
2653
2654 mutex_lock(&info->device->mutex);
2655 if (write_subdevice == NULL ||
2656 (write_subdevice->subdev_flags & SDF_CMD_WRITE) == 0 ||
2657 write_subdevice->async == NULL) {
2658 mutex_unlock(&info->device->mutex);
2659 return -EINVAL;
2660 }
2661 write_subdevice->async->max_bufsize = new_max_size;
2662 mutex_unlock(&info->device->mutex);
2663
2664 return count;
2665 }
2666
2667 static struct device_attribute dev_attr_max_write_buffer_kb = {
2668 .attr = {
2669 .name = "max_write_buffer_kb",
2670 .mode = S_IRUGO | S_IWUSR},
2671 .show = &show_max_write_buffer_kb,
2672 .store = &store_max_write_buffer_kb
2673 };
2674
show_write_buffer_kb(struct device * dev,struct device_attribute * attr,char * buf)2675 static ssize_t show_write_buffer_kb(struct device *dev,
2676 struct device_attribute *attr, char *buf)
2677 {
2678 ssize_t retval;
2679 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2680 unsigned buffer_size_kb = 0;
2681 struct comedi_subdevice *const write_subdevice =
2682 comedi_get_write_subdevice(info);
2683
2684 mutex_lock(&info->device->mutex);
2685 if (write_subdevice &&
2686 (write_subdevice->subdev_flags & SDF_CMD_WRITE) &&
2687 write_subdevice->async) {
2688 buffer_size_kb = write_subdevice->async->prealloc_bufsz /
2689 bytes_per_kibi;
2690 }
2691 retval = snprintf(buf, PAGE_SIZE, "%i\n", buffer_size_kb);
2692 mutex_unlock(&info->device->mutex);
2693
2694 return retval;
2695 }
2696
store_write_buffer_kb(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)2697 static ssize_t store_write_buffer_kb(struct device *dev,
2698 struct device_attribute *attr,
2699 const char *buf, size_t count)
2700 {
2701 struct comedi_device_file_info *info = dev_get_drvdata(dev);
2702 unsigned int new_size_kb;
2703 unsigned int new_size;
2704 int retval;
2705 int ret;
2706 struct comedi_subdevice *const write_subdevice =
2707 comedi_get_write_subdevice(info);
2708
2709 ret = kstrtouint(buf, 10, &new_size_kb);
2710 if (ret)
2711 return ret;
2712 if (new_size_kb > (UINT_MAX / bytes_per_kibi))
2713 return -EINVAL;
2714 new_size = ((uint64_t) new_size_kb) * bytes_per_kibi;
2715
2716 mutex_lock(&info->device->mutex);
2717 if (write_subdevice == NULL ||
2718 (write_subdevice->subdev_flags & SDF_CMD_WRITE) == 0 ||
2719 write_subdevice->async == NULL) {
2720 mutex_unlock(&info->device->mutex);
2721 return -EINVAL;
2722 }
2723 retval = resize_async_buffer(info->device, write_subdevice,
2724 write_subdevice->async, new_size);
2725 mutex_unlock(&info->device->mutex);
2726
2727 if (retval < 0)
2728 return retval;
2729 return count;
2730 }
2731
2732 static struct device_attribute dev_attr_write_buffer_kb = {
2733 .attr = {
2734 .name = "write_buffer_kb",
2735 .mode = S_IRUGO | S_IWUSR | S_IWGRP},
2736 .show = &show_write_buffer_kb,
2737 .store = &store_write_buffer_kb
2738 };
2739