1/* 2 comedi/comedi_fops.c 3 comedi kernel module 4 5 COMEDI - Linux Control and Measurement Device Interface 6 Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org> 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 2 of the License, or 11 (at your option) any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17*/ 18 19#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 20 21#include "comedi_compat32.h" 22 23#include <linux/module.h> 24#include <linux/errno.h> 25#include <linux/kernel.h> 26#include <linux/sched.h> 27#include <linux/fcntl.h> 28#include <linux/delay.h> 29#include <linux/mm.h> 30#include <linux/slab.h> 31#include <linux/kmod.h> 32#include <linux/poll.h> 33#include <linux/init.h> 34#include <linux/device.h> 35#include <linux/vmalloc.h> 36#include <linux/fs.h> 37#include "comedidev.h" 38#include <linux/cdev.h> 39#include <linux/stat.h> 40 41#include <linux/io.h> 42#include <linux/uaccess.h> 43 44#include "comedi_internal.h" 45 46#define COMEDI_NUM_MINORS 0x100 47#define COMEDI_NUM_SUBDEVICE_MINORS \ 48 (COMEDI_NUM_MINORS - COMEDI_NUM_BOARD_MINORS) 49 50static int comedi_num_legacy_minors; 51module_param(comedi_num_legacy_minors, int, S_IRUGO); 52MODULE_PARM_DESC(comedi_num_legacy_minors, 53 "number of comedi minor devices to reserve for non-auto-configured devices (default 0)" 54 ); 55 56unsigned int comedi_default_buf_size_kb = CONFIG_COMEDI_DEFAULT_BUF_SIZE_KB; 57module_param(comedi_default_buf_size_kb, uint, S_IRUGO | S_IWUSR); 58MODULE_PARM_DESC(comedi_default_buf_size_kb, 59 "default asynchronous buffer size in KiB (default " 60 __MODULE_STRING(CONFIG_COMEDI_DEFAULT_BUF_SIZE_KB) ")"); 61 62unsigned int comedi_default_buf_maxsize_kb 63 = CONFIG_COMEDI_DEFAULT_BUF_MAXSIZE_KB; 64module_param(comedi_default_buf_maxsize_kb, uint, S_IRUGO | S_IWUSR); 65MODULE_PARM_DESC(comedi_default_buf_maxsize_kb, 66 "default maximum size of asynchronous buffer in KiB (default " 67 __MODULE_STRING(CONFIG_COMEDI_DEFAULT_BUF_MAXSIZE_KB) ")"); 68 69static DEFINE_MUTEX(comedi_board_minor_table_lock); 70static struct comedi_device 71*comedi_board_minor_table[COMEDI_NUM_BOARD_MINORS]; 72 73static DEFINE_MUTEX(comedi_subdevice_minor_table_lock); 74/* Note: indexed by minor - COMEDI_NUM_BOARD_MINORS. */ 75static struct comedi_subdevice 76*comedi_subdevice_minor_table[COMEDI_NUM_SUBDEVICE_MINORS]; 77 78static struct class *comedi_class; 79static struct cdev comedi_cdev; 80 81static void comedi_device_init(struct comedi_device *dev) 82{ 83 kref_init(&dev->refcount); 84 spin_lock_init(&dev->spinlock); 85 mutex_init(&dev->mutex); 86 init_rwsem(&dev->attach_lock); 87 dev->minor = -1; 88} 89 90static void comedi_dev_kref_release(struct kref *kref) 91{ 92 struct comedi_device *dev = 93 container_of(kref, struct comedi_device, refcount); 94 95 mutex_destroy(&dev->mutex); 96 put_device(dev->class_dev); 97 kfree(dev); 98} 99 100int comedi_dev_put(struct comedi_device *dev) 101{ 102 if (dev) 103 return kref_put(&dev->refcount, comedi_dev_kref_release); 104 return 1; 105} 106EXPORT_SYMBOL_GPL(comedi_dev_put); 107 108static struct comedi_device *comedi_dev_get(struct comedi_device *dev) 109{ 110 if (dev) 111 kref_get(&dev->refcount); 112 return dev; 113} 114 115static void comedi_device_cleanup(struct comedi_device *dev) 116{ 117 struct module *driver_module = NULL; 118 119 if (dev == NULL) 120 return; 121 mutex_lock(&dev->mutex); 122 if (dev->attached) 123 driver_module = dev->driver->module; 124 comedi_device_detach(dev); 125 if (driver_module && dev->use_count) 126 module_put(driver_module); 127 mutex_unlock(&dev->mutex); 128} 129 130static bool comedi_clear_board_dev(struct comedi_device *dev) 131{ 132 unsigned int i = dev->minor; 133 bool cleared = false; 134 135 mutex_lock(&comedi_board_minor_table_lock); 136 if (dev == comedi_board_minor_table[i]) { 137 comedi_board_minor_table[i] = NULL; 138 cleared = true; 139 } 140 mutex_unlock(&comedi_board_minor_table_lock); 141 return cleared; 142} 143 144static struct comedi_device *comedi_clear_board_minor(unsigned minor) 145{ 146 struct comedi_device *dev; 147 148 mutex_lock(&comedi_board_minor_table_lock); 149 dev = comedi_board_minor_table[minor]; 150 comedi_board_minor_table[minor] = NULL; 151 mutex_unlock(&comedi_board_minor_table_lock); 152 return dev; 153} 154 155static void comedi_free_board_dev(struct comedi_device *dev) 156{ 157 if (dev) { 158 comedi_device_cleanup(dev); 159 if (dev->class_dev) { 160 device_destroy(comedi_class, 161 MKDEV(COMEDI_MAJOR, dev->minor)); 162 } 163 comedi_dev_put(dev); 164 } 165} 166 167static struct comedi_subdevice 168*comedi_subdevice_from_minor(const struct comedi_device *dev, unsigned minor) 169{ 170 struct comedi_subdevice *s; 171 unsigned int i = minor - COMEDI_NUM_BOARD_MINORS; 172 173 BUG_ON(i >= COMEDI_NUM_SUBDEVICE_MINORS); 174 mutex_lock(&comedi_subdevice_minor_table_lock); 175 s = comedi_subdevice_minor_table[i]; 176 if (s && s->device != dev) 177 s = NULL; 178 mutex_unlock(&comedi_subdevice_minor_table_lock); 179 return s; 180} 181 182static struct comedi_device *comedi_dev_get_from_board_minor(unsigned minor) 183{ 184 struct comedi_device *dev; 185 186 BUG_ON(minor >= COMEDI_NUM_BOARD_MINORS); 187 mutex_lock(&comedi_board_minor_table_lock); 188 dev = comedi_dev_get(comedi_board_minor_table[minor]); 189 mutex_unlock(&comedi_board_minor_table_lock); 190 return dev; 191} 192 193static struct comedi_device *comedi_dev_get_from_subdevice_minor(unsigned minor) 194{ 195 struct comedi_device *dev; 196 struct comedi_subdevice *s; 197 unsigned int i = minor - COMEDI_NUM_BOARD_MINORS; 198 199 BUG_ON(i >= COMEDI_NUM_SUBDEVICE_MINORS); 200 mutex_lock(&comedi_subdevice_minor_table_lock); 201 s = comedi_subdevice_minor_table[i]; 202 dev = comedi_dev_get(s ? s->device : NULL); 203 mutex_unlock(&comedi_subdevice_minor_table_lock); 204 return dev; 205} 206 207struct comedi_device *comedi_dev_get_from_minor(unsigned minor) 208{ 209 if (minor < COMEDI_NUM_BOARD_MINORS) 210 return comedi_dev_get_from_board_minor(minor); 211 212 return comedi_dev_get_from_subdevice_minor(minor); 213} 214EXPORT_SYMBOL_GPL(comedi_dev_get_from_minor); 215 216static struct comedi_subdevice * 217comedi_read_subdevice(const struct comedi_device *dev, unsigned int minor) 218{ 219 struct comedi_subdevice *s; 220 221 if (minor >= COMEDI_NUM_BOARD_MINORS) { 222 s = comedi_subdevice_from_minor(dev, minor); 223 if (s == NULL || (s->subdev_flags & SDF_CMD_READ)) 224 return s; 225 } 226 return dev->read_subdev; 227} 228 229static struct comedi_subdevice * 230comedi_write_subdevice(const struct comedi_device *dev, unsigned int minor) 231{ 232 struct comedi_subdevice *s; 233 234 if (minor >= COMEDI_NUM_BOARD_MINORS) { 235 s = comedi_subdevice_from_minor(dev, minor); 236 if (s == NULL || (s->subdev_flags & SDF_CMD_WRITE)) 237 return s; 238 } 239 return dev->write_subdev; 240} 241 242static int resize_async_buffer(struct comedi_device *dev, 243 struct comedi_subdevice *s, unsigned new_size) 244{ 245 struct comedi_async *async = s->async; 246 int retval; 247 248 if (new_size > async->max_bufsize) 249 return -EPERM; 250 251 if (s->busy) { 252 dev_dbg(dev->class_dev, 253 "subdevice is busy, cannot resize buffer\n"); 254 return -EBUSY; 255 } 256 if (comedi_buf_is_mmapped(s)) { 257 dev_dbg(dev->class_dev, 258 "subdevice is mmapped, cannot resize buffer\n"); 259 return -EBUSY; 260 } 261 262 /* make sure buffer is an integral number of pages 263 * (we round up) */ 264 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK; 265 266 retval = comedi_buf_alloc(dev, s, new_size); 267 if (retval < 0) 268 return retval; 269 270 if (s->buf_change) { 271 retval = s->buf_change(dev, s); 272 if (retval < 0) 273 return retval; 274 } 275 276 dev_dbg(dev->class_dev, "subd %d buffer resized to %i bytes\n", 277 s->index, async->prealloc_bufsz); 278 return 0; 279} 280 281/* sysfs attribute files */ 282 283static ssize_t max_read_buffer_kb_show(struct device *csdev, 284 struct device_attribute *attr, char *buf) 285{ 286 unsigned int minor = MINOR(csdev->devt); 287 struct comedi_device *dev; 288 struct comedi_subdevice *s; 289 unsigned int size = 0; 290 291 dev = comedi_dev_get_from_minor(minor); 292 if (!dev) 293 return -ENODEV; 294 295 mutex_lock(&dev->mutex); 296 s = comedi_read_subdevice(dev, minor); 297 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async) 298 size = s->async->max_bufsize / 1024; 299 mutex_unlock(&dev->mutex); 300 301 comedi_dev_put(dev); 302 return snprintf(buf, PAGE_SIZE, "%u\n", size); 303} 304 305static ssize_t max_read_buffer_kb_store(struct device *csdev, 306 struct device_attribute *attr, 307 const char *buf, size_t count) 308{ 309 unsigned int minor = MINOR(csdev->devt); 310 struct comedi_device *dev; 311 struct comedi_subdevice *s; 312 unsigned int size; 313 int err; 314 315 err = kstrtouint(buf, 10, &size); 316 if (err) 317 return err; 318 if (size > (UINT_MAX / 1024)) 319 return -EINVAL; 320 size *= 1024; 321 322 dev = comedi_dev_get_from_minor(minor); 323 if (!dev) 324 return -ENODEV; 325 326 mutex_lock(&dev->mutex); 327 s = comedi_read_subdevice(dev, minor); 328 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async) 329 s->async->max_bufsize = size; 330 else 331 err = -EINVAL; 332 mutex_unlock(&dev->mutex); 333 334 comedi_dev_put(dev); 335 return err ? err : count; 336} 337static DEVICE_ATTR_RW(max_read_buffer_kb); 338 339static ssize_t read_buffer_kb_show(struct device *csdev, 340 struct device_attribute *attr, char *buf) 341{ 342 unsigned int minor = MINOR(csdev->devt); 343 struct comedi_device *dev; 344 struct comedi_subdevice *s; 345 unsigned int size = 0; 346 347 dev = comedi_dev_get_from_minor(minor); 348 if (!dev) 349 return -ENODEV; 350 351 mutex_lock(&dev->mutex); 352 s = comedi_read_subdevice(dev, minor); 353 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async) 354 size = s->async->prealloc_bufsz / 1024; 355 mutex_unlock(&dev->mutex); 356 357 comedi_dev_put(dev); 358 return snprintf(buf, PAGE_SIZE, "%u\n", size); 359} 360 361static ssize_t read_buffer_kb_store(struct device *csdev, 362 struct device_attribute *attr, 363 const char *buf, size_t count) 364{ 365 unsigned int minor = MINOR(csdev->devt); 366 struct comedi_device *dev; 367 struct comedi_subdevice *s; 368 unsigned int size; 369 int err; 370 371 err = kstrtouint(buf, 10, &size); 372 if (err) 373 return err; 374 if (size > (UINT_MAX / 1024)) 375 return -EINVAL; 376 size *= 1024; 377 378 dev = comedi_dev_get_from_minor(minor); 379 if (!dev) 380 return -ENODEV; 381 382 mutex_lock(&dev->mutex); 383 s = comedi_read_subdevice(dev, minor); 384 if (s && (s->subdev_flags & SDF_CMD_READ) && s->async) 385 err = resize_async_buffer(dev, s, size); 386 else 387 err = -EINVAL; 388 mutex_unlock(&dev->mutex); 389 390 comedi_dev_put(dev); 391 return err ? err : count; 392} 393static DEVICE_ATTR_RW(read_buffer_kb); 394 395static ssize_t max_write_buffer_kb_show(struct device *csdev, 396 struct device_attribute *attr, 397 char *buf) 398{ 399 unsigned int minor = MINOR(csdev->devt); 400 struct comedi_device *dev; 401 struct comedi_subdevice *s; 402 unsigned int size = 0; 403 404 dev = comedi_dev_get_from_minor(minor); 405 if (!dev) 406 return -ENODEV; 407 408 mutex_lock(&dev->mutex); 409 s = comedi_write_subdevice(dev, minor); 410 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async) 411 size = s->async->max_bufsize / 1024; 412 mutex_unlock(&dev->mutex); 413 414 comedi_dev_put(dev); 415 return snprintf(buf, PAGE_SIZE, "%u\n", size); 416} 417 418static ssize_t max_write_buffer_kb_store(struct device *csdev, 419 struct device_attribute *attr, 420 const char *buf, size_t count) 421{ 422 unsigned int minor = MINOR(csdev->devt); 423 struct comedi_device *dev; 424 struct comedi_subdevice *s; 425 unsigned int size; 426 int err; 427 428 err = kstrtouint(buf, 10, &size); 429 if (err) 430 return err; 431 if (size > (UINT_MAX / 1024)) 432 return -EINVAL; 433 size *= 1024; 434 435 dev = comedi_dev_get_from_minor(minor); 436 if (!dev) 437 return -ENODEV; 438 439 mutex_lock(&dev->mutex); 440 s = comedi_write_subdevice(dev, minor); 441 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async) 442 s->async->max_bufsize = size; 443 else 444 err = -EINVAL; 445 mutex_unlock(&dev->mutex); 446 447 comedi_dev_put(dev); 448 return err ? err : count; 449} 450static DEVICE_ATTR_RW(max_write_buffer_kb); 451 452static ssize_t write_buffer_kb_show(struct device *csdev, 453 struct device_attribute *attr, char *buf) 454{ 455 unsigned int minor = MINOR(csdev->devt); 456 struct comedi_device *dev; 457 struct comedi_subdevice *s; 458 unsigned int size = 0; 459 460 dev = comedi_dev_get_from_minor(minor); 461 if (!dev) 462 return -ENODEV; 463 464 mutex_lock(&dev->mutex); 465 s = comedi_write_subdevice(dev, minor); 466 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async) 467 size = s->async->prealloc_bufsz / 1024; 468 mutex_unlock(&dev->mutex); 469 470 comedi_dev_put(dev); 471 return snprintf(buf, PAGE_SIZE, "%u\n", size); 472} 473 474static ssize_t write_buffer_kb_store(struct device *csdev, 475 struct device_attribute *attr, 476 const char *buf, size_t count) 477{ 478 unsigned int minor = MINOR(csdev->devt); 479 struct comedi_device *dev; 480 struct comedi_subdevice *s; 481 unsigned int size; 482 int err; 483 484 err = kstrtouint(buf, 10, &size); 485 if (err) 486 return err; 487 if (size > (UINT_MAX / 1024)) 488 return -EINVAL; 489 size *= 1024; 490 491 dev = comedi_dev_get_from_minor(minor); 492 if (!dev) 493 return -ENODEV; 494 495 mutex_lock(&dev->mutex); 496 s = comedi_write_subdevice(dev, minor); 497 if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async) 498 err = resize_async_buffer(dev, s, size); 499 else 500 err = -EINVAL; 501 mutex_unlock(&dev->mutex); 502 503 comedi_dev_put(dev); 504 return err ? err : count; 505} 506static DEVICE_ATTR_RW(write_buffer_kb); 507 508static struct attribute *comedi_dev_attrs[] = { 509 &dev_attr_max_read_buffer_kb.attr, 510 &dev_attr_read_buffer_kb.attr, 511 &dev_attr_max_write_buffer_kb.attr, 512 &dev_attr_write_buffer_kb.attr, 513 NULL, 514}; 515ATTRIBUTE_GROUPS(comedi_dev); 516 517static void comedi_set_subdevice_runflags(struct comedi_subdevice *s, 518 unsigned mask, unsigned bits) 519{ 520 unsigned long flags; 521 522 spin_lock_irqsave(&s->spin_lock, flags); 523 s->runflags &= ~mask; 524 s->runflags |= (bits & mask); 525 spin_unlock_irqrestore(&s->spin_lock, flags); 526} 527 528static unsigned comedi_get_subdevice_runflags(struct comedi_subdevice *s) 529{ 530 unsigned long flags; 531 unsigned runflags; 532 533 spin_lock_irqsave(&s->spin_lock, flags); 534 runflags = s->runflags; 535 spin_unlock_irqrestore(&s->spin_lock, flags); 536 return runflags; 537} 538 539bool comedi_is_subdevice_running(struct comedi_subdevice *s) 540{ 541 unsigned runflags = comedi_get_subdevice_runflags(s); 542 543 return (runflags & SRF_RUNNING) ? true : false; 544} 545EXPORT_SYMBOL_GPL(comedi_is_subdevice_running); 546 547static bool comedi_is_subdevice_in_error(struct comedi_subdevice *s) 548{ 549 unsigned runflags = comedi_get_subdevice_runflags(s); 550 551 return (runflags & SRF_ERROR) ? true : false; 552} 553 554static bool comedi_is_subdevice_idle(struct comedi_subdevice *s) 555{ 556 unsigned runflags = comedi_get_subdevice_runflags(s); 557 558 return (runflags & (SRF_ERROR | SRF_RUNNING)) ? false : true; 559} 560 561/** 562 * comedi_alloc_spriv() - Allocate memory for the subdevice private data. 563 * @s: comedi_subdevice struct 564 * @size: size of the memory to allocate 565 * 566 * This also sets the subdevice runflags to allow the core to automatically 567 * free the private data during the detach. 568 */ 569void *comedi_alloc_spriv(struct comedi_subdevice *s, size_t size) 570{ 571 s->private = kzalloc(size, GFP_KERNEL); 572 if (s->private) 573 s->runflags |= SRF_FREE_SPRIV; 574 return s->private; 575} 576EXPORT_SYMBOL_GPL(comedi_alloc_spriv); 577 578/* 579 This function restores a subdevice to an idle state. 580 */ 581static void do_become_nonbusy(struct comedi_device *dev, 582 struct comedi_subdevice *s) 583{ 584 struct comedi_async *async = s->async; 585 586 comedi_set_subdevice_runflags(s, SRF_RUNNING, 0); 587 if (async) { 588 comedi_buf_reset(s); 589 async->inttrig = NULL; 590 kfree(async->cmd.chanlist); 591 async->cmd.chanlist = NULL; 592 s->busy = NULL; 593 wake_up_interruptible_all(&s->async->wait_head); 594 } else { 595 dev_err(dev->class_dev, 596 "BUG: (?) do_become_nonbusy called with async=NULL\n"); 597 s->busy = NULL; 598 } 599} 600 601static int do_cancel(struct comedi_device *dev, struct comedi_subdevice *s) 602{ 603 int ret = 0; 604 605 if (comedi_is_subdevice_running(s) && s->cancel) 606 ret = s->cancel(dev, s); 607 608 do_become_nonbusy(dev, s); 609 610 return ret; 611} 612 613void comedi_device_cancel_all(struct comedi_device *dev) 614{ 615 struct comedi_subdevice *s; 616 int i; 617 618 if (!dev->attached) 619 return; 620 621 for (i = 0; i < dev->n_subdevices; i++) { 622 s = &dev->subdevices[i]; 623 if (s->async) 624 do_cancel(dev, s); 625 } 626} 627 628static int is_device_busy(struct comedi_device *dev) 629{ 630 struct comedi_subdevice *s; 631 int i; 632 633 if (!dev->attached) 634 return 0; 635 636 for (i = 0; i < dev->n_subdevices; i++) { 637 s = &dev->subdevices[i]; 638 if (s->busy) 639 return 1; 640 if (s->async && comedi_buf_is_mmapped(s)) 641 return 1; 642 } 643 644 return 0; 645} 646 647/* 648 COMEDI_DEVCONFIG 649 device config ioctl 650 651 arg: 652 pointer to devconfig structure 653 654 reads: 655 devconfig structure at arg 656 657 writes: 658 none 659*/ 660static int do_devconfig_ioctl(struct comedi_device *dev, 661 struct comedi_devconfig __user *arg) 662{ 663 struct comedi_devconfig it; 664 665 if (!capable(CAP_SYS_ADMIN)) 666 return -EPERM; 667 668 if (arg == NULL) { 669 if (is_device_busy(dev)) 670 return -EBUSY; 671 if (dev->attached) { 672 struct module *driver_module = dev->driver->module; 673 674 comedi_device_detach(dev); 675 module_put(driver_module); 676 } 677 return 0; 678 } 679 680 if (copy_from_user(&it, arg, sizeof(it))) 681 return -EFAULT; 682 683 it.board_name[COMEDI_NAMELEN - 1] = 0; 684 685 if (it.options[COMEDI_DEVCONF_AUX_DATA_LENGTH]) { 686 dev_warn(dev->class_dev, 687 "comedi_config --init_data is deprecated\n"); 688 return -EINVAL; 689 } 690 691 if (dev->minor >= comedi_num_legacy_minors) 692 /* don't re-use dynamically allocated comedi devices */ 693 return -EBUSY; 694 695 /* This increments the driver module count on success. */ 696 return comedi_device_attach(dev, &it); 697} 698 699/* 700 COMEDI_BUFCONFIG 701 buffer configuration ioctl 702 703 arg: 704 pointer to bufconfig structure 705 706 reads: 707 bufconfig at arg 708 709 writes: 710 modified bufconfig at arg 711 712*/ 713static int do_bufconfig_ioctl(struct comedi_device *dev, 714 struct comedi_bufconfig __user *arg) 715{ 716 struct comedi_bufconfig bc; 717 struct comedi_async *async; 718 struct comedi_subdevice *s; 719 int retval = 0; 720 721 if (copy_from_user(&bc, arg, sizeof(bc))) 722 return -EFAULT; 723 724 if (bc.subdevice >= dev->n_subdevices) 725 return -EINVAL; 726 727 s = &dev->subdevices[bc.subdevice]; 728 async = s->async; 729 730 if (!async) { 731 dev_dbg(dev->class_dev, 732 "subdevice does not have async capability\n"); 733 bc.size = 0; 734 bc.maximum_size = 0; 735 goto copyback; 736 } 737 738 if (bc.maximum_size) { 739 if (!capable(CAP_SYS_ADMIN)) 740 return -EPERM; 741 742 async->max_bufsize = bc.maximum_size; 743 } 744 745 if (bc.size) { 746 retval = resize_async_buffer(dev, s, bc.size); 747 if (retval < 0) 748 return retval; 749 } 750 751 bc.size = async->prealloc_bufsz; 752 bc.maximum_size = async->max_bufsize; 753 754copyback: 755 if (copy_to_user(arg, &bc, sizeof(bc))) 756 return -EFAULT; 757 758 return 0; 759} 760 761/* 762 COMEDI_DEVINFO 763 device info ioctl 764 765 arg: 766 pointer to devinfo structure 767 768 reads: 769 none 770 771 writes: 772 devinfo structure 773 774*/ 775static int do_devinfo_ioctl(struct comedi_device *dev, 776 struct comedi_devinfo __user *arg, 777 struct file *file) 778{ 779 const unsigned minor = iminor(file_inode(file)); 780 struct comedi_subdevice *s; 781 struct comedi_devinfo devinfo; 782 783 memset(&devinfo, 0, sizeof(devinfo)); 784 785 /* fill devinfo structure */ 786 devinfo.version_code = COMEDI_VERSION_CODE; 787 devinfo.n_subdevs = dev->n_subdevices; 788 strlcpy(devinfo.driver_name, dev->driver->driver_name, COMEDI_NAMELEN); 789 strlcpy(devinfo.board_name, dev->board_name, COMEDI_NAMELEN); 790 791 s = comedi_read_subdevice(dev, minor); 792 if (s) 793 devinfo.read_subdevice = s->index; 794 else 795 devinfo.read_subdevice = -1; 796 797 s = comedi_write_subdevice(dev, minor); 798 if (s) 799 devinfo.write_subdevice = s->index; 800 else 801 devinfo.write_subdevice = -1; 802 803 if (copy_to_user(arg, &devinfo, sizeof(devinfo))) 804 return -EFAULT; 805 806 return 0; 807} 808 809/* 810 COMEDI_SUBDINFO 811 subdevice info ioctl 812 813 arg: 814 pointer to array of subdevice info structures 815 816 reads: 817 none 818 819 writes: 820 array of subdevice info structures at arg 821 822*/ 823static int do_subdinfo_ioctl(struct comedi_device *dev, 824 struct comedi_subdinfo __user *arg, void *file) 825{ 826 int ret, i; 827 struct comedi_subdinfo *tmp, *us; 828 struct comedi_subdevice *s; 829 830 tmp = kcalloc(dev->n_subdevices, sizeof(*tmp), GFP_KERNEL); 831 if (!tmp) 832 return -ENOMEM; 833 834 /* fill subdinfo structs */ 835 for (i = 0; i < dev->n_subdevices; i++) { 836 s = &dev->subdevices[i]; 837 us = tmp + i; 838 839 us->type = s->type; 840 us->n_chan = s->n_chan; 841 us->subd_flags = s->subdev_flags; 842 if (comedi_is_subdevice_running(s)) 843 us->subd_flags |= SDF_RUNNING; 844#define TIMER_nanosec 5 /* backwards compatibility */ 845 us->timer_type = TIMER_nanosec; 846 us->len_chanlist = s->len_chanlist; 847 us->maxdata = s->maxdata; 848 if (s->range_table) { 849 us->range_type = 850 (i << 24) | (0 << 16) | (s->range_table->length); 851 } else { 852 us->range_type = 0; /* XXX */ 853 } 854 855 if (s->busy) 856 us->subd_flags |= SDF_BUSY; 857 if (s->busy == file) 858 us->subd_flags |= SDF_BUSY_OWNER; 859 if (s->lock) 860 us->subd_flags |= SDF_LOCKED; 861 if (s->lock == file) 862 us->subd_flags |= SDF_LOCK_OWNER; 863 if (!s->maxdata && s->maxdata_list) 864 us->subd_flags |= SDF_MAXDATA; 865 if (s->range_table_list) 866 us->subd_flags |= SDF_RANGETYPE; 867 if (s->do_cmd) 868 us->subd_flags |= SDF_CMD; 869 870 if (s->insn_bits != &insn_inval) 871 us->insn_bits_support = COMEDI_SUPPORTED; 872 else 873 us->insn_bits_support = COMEDI_UNSUPPORTED; 874 } 875 876 ret = copy_to_user(arg, tmp, dev->n_subdevices * sizeof(*tmp)); 877 878 kfree(tmp); 879 880 return ret ? -EFAULT : 0; 881} 882 883/* 884 COMEDI_CHANINFO 885 subdevice info ioctl 886 887 arg: 888 pointer to chaninfo structure 889 890 reads: 891 chaninfo structure at arg 892 893 writes: 894 arrays at elements of chaninfo structure 895 896*/ 897static int do_chaninfo_ioctl(struct comedi_device *dev, 898 struct comedi_chaninfo __user *arg) 899{ 900 struct comedi_subdevice *s; 901 struct comedi_chaninfo it; 902 903 if (copy_from_user(&it, arg, sizeof(it))) 904 return -EFAULT; 905 906 if (it.subdev >= dev->n_subdevices) 907 return -EINVAL; 908 s = &dev->subdevices[it.subdev]; 909 910 if (it.maxdata_list) { 911 if (s->maxdata || !s->maxdata_list) 912 return -EINVAL; 913 if (copy_to_user(it.maxdata_list, s->maxdata_list, 914 s->n_chan * sizeof(unsigned int))) 915 return -EFAULT; 916 } 917 918 if (it.flaglist) 919 return -EINVAL; /* flaglist not supported */ 920 921 if (it.rangelist) { 922 int i; 923 924 if (!s->range_table_list) 925 return -EINVAL; 926 for (i = 0; i < s->n_chan; i++) { 927 int x; 928 929 x = (dev->minor << 28) | (it.subdev << 24) | (i << 16) | 930 (s->range_table_list[i]->length); 931 if (put_user(x, it.rangelist + i)) 932 return -EFAULT; 933 } 934#if 0 935 if (copy_to_user(it.rangelist, s->range_type_list, 936 s->n_chan * sizeof(unsigned int))) 937 return -EFAULT; 938#endif 939 } 940 941 return 0; 942} 943 944 /* 945 COMEDI_BUFINFO 946 buffer information ioctl 947 948 arg: 949 pointer to bufinfo structure 950 951 reads: 952 bufinfo at arg 953 954 writes: 955 modified bufinfo at arg 956 957 */ 958static int do_bufinfo_ioctl(struct comedi_device *dev, 959 struct comedi_bufinfo __user *arg, void *file) 960{ 961 struct comedi_bufinfo bi; 962 struct comedi_subdevice *s; 963 struct comedi_async *async; 964 965 if (copy_from_user(&bi, arg, sizeof(bi))) 966 return -EFAULT; 967 968 if (bi.subdevice >= dev->n_subdevices) 969 return -EINVAL; 970 971 s = &dev->subdevices[bi.subdevice]; 972 973 async = s->async; 974 975 if (!async) { 976 dev_dbg(dev->class_dev, 977 "subdevice does not have async capability\n"); 978 bi.buf_write_ptr = 0; 979 bi.buf_read_ptr = 0; 980 bi.buf_write_count = 0; 981 bi.buf_read_count = 0; 982 bi.bytes_read = 0; 983 bi.bytes_written = 0; 984 goto copyback; 985 } 986 if (!s->busy) { 987 bi.bytes_read = 0; 988 bi.bytes_written = 0; 989 goto copyback_position; 990 } 991 if (s->busy != file) 992 return -EACCES; 993 994 if (bi.bytes_read && (s->subdev_flags & SDF_CMD_READ)) { 995 bi.bytes_read = comedi_buf_read_alloc(s, bi.bytes_read); 996 comedi_buf_read_free(s, bi.bytes_read); 997 998 if (comedi_is_subdevice_idle(s) && 999 comedi_buf_n_bytes_ready(s) == 0) { 1000 do_become_nonbusy(dev, s); 1001 } 1002 } 1003 1004 if (bi.bytes_written && (s->subdev_flags & SDF_CMD_WRITE)) { 1005 bi.bytes_written = 1006 comedi_buf_write_alloc(s, bi.bytes_written); 1007 comedi_buf_write_free(s, bi.bytes_written); 1008 } 1009 1010copyback_position: 1011 bi.buf_write_count = async->buf_write_count; 1012 bi.buf_write_ptr = async->buf_write_ptr; 1013 bi.buf_read_count = async->buf_read_count; 1014 bi.buf_read_ptr = async->buf_read_ptr; 1015 1016copyback: 1017 if (copy_to_user(arg, &bi, sizeof(bi))) 1018 return -EFAULT; 1019 1020 return 0; 1021} 1022 1023static int check_insn_config_length(struct comedi_insn *insn, 1024 unsigned int *data) 1025{ 1026 if (insn->n < 1) 1027 return -EINVAL; 1028 1029 switch (data[0]) { 1030 case INSN_CONFIG_DIO_OUTPUT: 1031 case INSN_CONFIG_DIO_INPUT: 1032 case INSN_CONFIG_DISARM: 1033 case INSN_CONFIG_RESET: 1034 if (insn->n == 1) 1035 return 0; 1036 break; 1037 case INSN_CONFIG_ARM: 1038 case INSN_CONFIG_DIO_QUERY: 1039 case INSN_CONFIG_BLOCK_SIZE: 1040 case INSN_CONFIG_FILTER: 1041 case INSN_CONFIG_SERIAL_CLOCK: 1042 case INSN_CONFIG_BIDIRECTIONAL_DATA: 1043 case INSN_CONFIG_ALT_SOURCE: 1044 case INSN_CONFIG_SET_COUNTER_MODE: 1045 case INSN_CONFIG_8254_READ_STATUS: 1046 case INSN_CONFIG_SET_ROUTING: 1047 case INSN_CONFIG_GET_ROUTING: 1048 case INSN_CONFIG_GET_PWM_STATUS: 1049 case INSN_CONFIG_PWM_SET_PERIOD: 1050 case INSN_CONFIG_PWM_GET_PERIOD: 1051 if (insn->n == 2) 1052 return 0; 1053 break; 1054 case INSN_CONFIG_SET_GATE_SRC: 1055 case INSN_CONFIG_GET_GATE_SRC: 1056 case INSN_CONFIG_SET_CLOCK_SRC: 1057 case INSN_CONFIG_GET_CLOCK_SRC: 1058 case INSN_CONFIG_SET_OTHER_SRC: 1059 case INSN_CONFIG_GET_COUNTER_STATUS: 1060 case INSN_CONFIG_PWM_SET_H_BRIDGE: 1061 case INSN_CONFIG_PWM_GET_H_BRIDGE: 1062 case INSN_CONFIG_GET_HARDWARE_BUFFER_SIZE: 1063 if (insn->n == 3) 1064 return 0; 1065 break; 1066 case INSN_CONFIG_PWM_OUTPUT: 1067 case INSN_CONFIG_ANALOG_TRIG: 1068 if (insn->n == 5) 1069 return 0; 1070 break; 1071 case INSN_CONFIG_DIGITAL_TRIG: 1072 if (insn->n == 6) 1073 return 0; 1074 break; 1075 /* by default we allow the insn since we don't have checks for 1076 * all possible cases yet */ 1077 default: 1078 pr_warn("No check for data length of config insn id %i is implemented\n", 1079 data[0]); 1080 pr_warn("Add a check to %s in %s\n", __func__, __FILE__); 1081 pr_warn("Assuming n=%i is correct\n", insn->n); 1082 return 0; 1083 } 1084 return -EINVAL; 1085} 1086 1087static int parse_insn(struct comedi_device *dev, struct comedi_insn *insn, 1088 unsigned int *data, void *file) 1089{ 1090 struct comedi_subdevice *s; 1091 int ret = 0; 1092 int i; 1093 1094 if (insn->insn & INSN_MASK_SPECIAL) { 1095 /* a non-subdevice instruction */ 1096 1097 switch (insn->insn) { 1098 case INSN_GTOD: 1099 { 1100 struct timeval tv; 1101 1102 if (insn->n != 2) { 1103 ret = -EINVAL; 1104 break; 1105 } 1106 1107 do_gettimeofday(&tv); 1108 data[0] = tv.tv_sec; 1109 data[1] = tv.tv_usec; 1110 ret = 2; 1111 1112 break; 1113 } 1114 case INSN_WAIT: 1115 if (insn->n != 1 || data[0] >= 100000) { 1116 ret = -EINVAL; 1117 break; 1118 } 1119 udelay(data[0] / 1000); 1120 ret = 1; 1121 break; 1122 case INSN_INTTRIG: 1123 if (insn->n != 1) { 1124 ret = -EINVAL; 1125 break; 1126 } 1127 if (insn->subdev >= dev->n_subdevices) { 1128 dev_dbg(dev->class_dev, 1129 "%d not usable subdevice\n", 1130 insn->subdev); 1131 ret = -EINVAL; 1132 break; 1133 } 1134 s = &dev->subdevices[insn->subdev]; 1135 if (!s->async) { 1136 dev_dbg(dev->class_dev, "no async\n"); 1137 ret = -EINVAL; 1138 break; 1139 } 1140 if (!s->async->inttrig) { 1141 dev_dbg(dev->class_dev, "no inttrig\n"); 1142 ret = -EAGAIN; 1143 break; 1144 } 1145 ret = s->async->inttrig(dev, s, data[0]); 1146 if (ret >= 0) 1147 ret = 1; 1148 break; 1149 default: 1150 dev_dbg(dev->class_dev, "invalid insn\n"); 1151 ret = -EINVAL; 1152 break; 1153 } 1154 } else { 1155 /* a subdevice instruction */ 1156 unsigned int maxdata; 1157 1158 if (insn->subdev >= dev->n_subdevices) { 1159 dev_dbg(dev->class_dev, "subdevice %d out of range\n", 1160 insn->subdev); 1161 ret = -EINVAL; 1162 goto out; 1163 } 1164 s = &dev->subdevices[insn->subdev]; 1165 1166 if (s->type == COMEDI_SUBD_UNUSED) { 1167 dev_dbg(dev->class_dev, "%d not usable subdevice\n", 1168 insn->subdev); 1169 ret = -EIO; 1170 goto out; 1171 } 1172 1173 /* are we locked? (ioctl lock) */ 1174 if (s->lock && s->lock != file) { 1175 dev_dbg(dev->class_dev, "device locked\n"); 1176 ret = -EACCES; 1177 goto out; 1178 } 1179 1180 ret = comedi_check_chanlist(s, 1, &insn->chanspec); 1181 if (ret < 0) { 1182 ret = -EINVAL; 1183 dev_dbg(dev->class_dev, "bad chanspec\n"); 1184 goto out; 1185 } 1186 1187 if (s->busy) { 1188 ret = -EBUSY; 1189 goto out; 1190 } 1191 /* This looks arbitrary. It is. */ 1192 s->busy = &parse_insn; 1193 switch (insn->insn) { 1194 case INSN_READ: 1195 ret = s->insn_read(dev, s, insn, data); 1196 if (ret == -ETIMEDOUT) { 1197 dev_dbg(dev->class_dev, 1198 "subdevice %d read instruction timed out\n", 1199 s->index); 1200 } 1201 break; 1202 case INSN_WRITE: 1203 maxdata = s->maxdata_list 1204 ? s->maxdata_list[CR_CHAN(insn->chanspec)] 1205 : s->maxdata; 1206 for (i = 0; i < insn->n; ++i) { 1207 if (data[i] > maxdata) { 1208 ret = -EINVAL; 1209 dev_dbg(dev->class_dev, 1210 "bad data value(s)\n"); 1211 break; 1212 } 1213 } 1214 if (ret == 0) { 1215 ret = s->insn_write(dev, s, insn, data); 1216 if (ret == -ETIMEDOUT) { 1217 dev_dbg(dev->class_dev, 1218 "subdevice %d write instruction timed out\n", 1219 s->index); 1220 } 1221 } 1222 break; 1223 case INSN_BITS: 1224 if (insn->n != 2) { 1225 ret = -EINVAL; 1226 } else { 1227 /* Most drivers ignore the base channel in 1228 * insn->chanspec. Fix this here if 1229 * the subdevice has <= 32 channels. */ 1230 unsigned int orig_mask = data[0]; 1231 unsigned int shift = 0; 1232 1233 if (s->n_chan <= 32) { 1234 shift = CR_CHAN(insn->chanspec); 1235 if (shift > 0) { 1236 insn->chanspec = 0; 1237 data[0] <<= shift; 1238 data[1] <<= shift; 1239 } 1240 } 1241 ret = s->insn_bits(dev, s, insn, data); 1242 data[0] = orig_mask; 1243 if (shift > 0) 1244 data[1] >>= shift; 1245 } 1246 break; 1247 case INSN_CONFIG: 1248 ret = check_insn_config_length(insn, data); 1249 if (ret) 1250 break; 1251 ret = s->insn_config(dev, s, insn, data); 1252 break; 1253 default: 1254 ret = -EINVAL; 1255 break; 1256 } 1257 1258 s->busy = NULL; 1259 } 1260 1261out: 1262 return ret; 1263} 1264 1265/* 1266 * COMEDI_INSNLIST 1267 * synchronous instructions 1268 * 1269 * arg: 1270 * pointer to sync cmd structure 1271 * 1272 * reads: 1273 * sync cmd struct at arg 1274 * instruction list 1275 * data (for writes) 1276 * 1277 * writes: 1278 * data (for reads) 1279 */ 1280/* arbitrary limits */ 1281#define MAX_SAMPLES 256 1282static int do_insnlist_ioctl(struct comedi_device *dev, 1283 struct comedi_insnlist __user *arg, void *file) 1284{ 1285 struct comedi_insnlist insnlist; 1286 struct comedi_insn *insns = NULL; 1287 unsigned int *data = NULL; 1288 int i = 0; 1289 int ret = 0; 1290 1291 if (copy_from_user(&insnlist, arg, sizeof(insnlist))) 1292 return -EFAULT; 1293 1294 data = kmalloc_array(MAX_SAMPLES, sizeof(unsigned int), GFP_KERNEL); 1295 if (!data) { 1296 ret = -ENOMEM; 1297 goto error; 1298 } 1299 1300 insns = kcalloc(insnlist.n_insns, sizeof(*insns), GFP_KERNEL); 1301 if (!insns) { 1302 ret = -ENOMEM; 1303 goto error; 1304 } 1305 1306 if (copy_from_user(insns, insnlist.insns, 1307 sizeof(*insns) * insnlist.n_insns)) { 1308 dev_dbg(dev->class_dev, "copy_from_user failed\n"); 1309 ret = -EFAULT; 1310 goto error; 1311 } 1312 1313 for (i = 0; i < insnlist.n_insns; i++) { 1314 if (insns[i].n > MAX_SAMPLES) { 1315 dev_dbg(dev->class_dev, 1316 "number of samples too large\n"); 1317 ret = -EINVAL; 1318 goto error; 1319 } 1320 if (insns[i].insn & INSN_MASK_WRITE) { 1321 if (copy_from_user(data, insns[i].data, 1322 insns[i].n * sizeof(unsigned int))) { 1323 dev_dbg(dev->class_dev, 1324 "copy_from_user failed\n"); 1325 ret = -EFAULT; 1326 goto error; 1327 } 1328 } 1329 ret = parse_insn(dev, insns + i, data, file); 1330 if (ret < 0) 1331 goto error; 1332 if (insns[i].insn & INSN_MASK_READ) { 1333 if (copy_to_user(insns[i].data, data, 1334 insns[i].n * sizeof(unsigned int))) { 1335 dev_dbg(dev->class_dev, 1336 "copy_to_user failed\n"); 1337 ret = -EFAULT; 1338 goto error; 1339 } 1340 } 1341 if (need_resched()) 1342 schedule(); 1343 } 1344 1345error: 1346 kfree(insns); 1347 kfree(data); 1348 1349 if (ret < 0) 1350 return ret; 1351 return i; 1352} 1353 1354/* 1355 * COMEDI_INSN 1356 * synchronous instructions 1357 * 1358 * arg: 1359 * pointer to insn 1360 * 1361 * reads: 1362 * struct comedi_insn struct at arg 1363 * data (for writes) 1364 * 1365 * writes: 1366 * data (for reads) 1367 */ 1368static int do_insn_ioctl(struct comedi_device *dev, 1369 struct comedi_insn __user *arg, void *file) 1370{ 1371 struct comedi_insn insn; 1372 unsigned int *data = NULL; 1373 int ret = 0; 1374 1375 data = kmalloc_array(MAX_SAMPLES, sizeof(unsigned int), GFP_KERNEL); 1376 if (!data) { 1377 ret = -ENOMEM; 1378 goto error; 1379 } 1380 1381 if (copy_from_user(&insn, arg, sizeof(insn))) { 1382 ret = -EFAULT; 1383 goto error; 1384 } 1385 1386 /* This is where the behavior of insn and insnlist deviate. */ 1387 if (insn.n > MAX_SAMPLES) 1388 insn.n = MAX_SAMPLES; 1389 if (insn.insn & INSN_MASK_WRITE) { 1390 if (copy_from_user(data, 1391 insn.data, 1392 insn.n * sizeof(unsigned int))) { 1393 ret = -EFAULT; 1394 goto error; 1395 } 1396 } 1397 ret = parse_insn(dev, &insn, data, file); 1398 if (ret < 0) 1399 goto error; 1400 if (insn.insn & INSN_MASK_READ) { 1401 if (copy_to_user(insn.data, 1402 data, 1403 insn.n * sizeof(unsigned int))) { 1404 ret = -EFAULT; 1405 goto error; 1406 } 1407 } 1408 ret = insn.n; 1409 1410error: 1411 kfree(data); 1412 1413 return ret; 1414} 1415 1416static int __comedi_get_user_cmd(struct comedi_device *dev, 1417 struct comedi_cmd __user *arg, 1418 struct comedi_cmd *cmd) 1419{ 1420 struct comedi_subdevice *s; 1421 1422 if (copy_from_user(cmd, arg, sizeof(*cmd))) { 1423 dev_dbg(dev->class_dev, "bad cmd address\n"); 1424 return -EFAULT; 1425 } 1426 1427 if (cmd->subdev >= dev->n_subdevices) { 1428 dev_dbg(dev->class_dev, "%d no such subdevice\n", cmd->subdev); 1429 return -ENODEV; 1430 } 1431 1432 s = &dev->subdevices[cmd->subdev]; 1433 1434 if (s->type == COMEDI_SUBD_UNUSED) { 1435 dev_dbg(dev->class_dev, "%d not valid subdevice\n", 1436 cmd->subdev); 1437 return -EIO; 1438 } 1439 1440 if (!s->do_cmd || !s->do_cmdtest || !s->async) { 1441 dev_dbg(dev->class_dev, 1442 "subdevice %d does not support commands\n", 1443 cmd->subdev); 1444 return -EIO; 1445 } 1446 1447 /* make sure channel/gain list isn't too long */ 1448 if (cmd->chanlist_len > s->len_chanlist) { 1449 dev_dbg(dev->class_dev, "channel/gain list too long %d > %d\n", 1450 cmd->chanlist_len, s->len_chanlist); 1451 return -EINVAL; 1452 } 1453 1454 return 0; 1455} 1456 1457static int __comedi_get_user_chanlist(struct comedi_device *dev, 1458 struct comedi_subdevice *s, 1459 unsigned int __user *user_chanlist, 1460 struct comedi_cmd *cmd) 1461{ 1462 unsigned int *chanlist; 1463 int ret; 1464 1465 cmd->chanlist = NULL; 1466 chanlist = memdup_user(user_chanlist, 1467 cmd->chanlist_len * sizeof(unsigned int)); 1468 if (IS_ERR(chanlist)) 1469 return PTR_ERR(chanlist); 1470 1471 /* make sure each element in channel/gain list is valid */ 1472 ret = comedi_check_chanlist(s, cmd->chanlist_len, chanlist); 1473 if (ret < 0) { 1474 kfree(chanlist); 1475 return ret; 1476 } 1477 1478 cmd->chanlist = chanlist; 1479 1480 return 0; 1481} 1482 1483static int do_cmd_ioctl(struct comedi_device *dev, 1484 struct comedi_cmd __user *arg, void *file) 1485{ 1486 struct comedi_cmd cmd; 1487 struct comedi_subdevice *s; 1488 struct comedi_async *async; 1489 unsigned int __user *user_chanlist; 1490 int ret; 1491 1492 /* get the user's cmd and do some simple validation */ 1493 ret = __comedi_get_user_cmd(dev, arg, &cmd); 1494 if (ret) 1495 return ret; 1496 1497 /* save user's chanlist pointer so it can be restored later */ 1498 user_chanlist = (unsigned int __user *)cmd.chanlist; 1499 1500 s = &dev->subdevices[cmd.subdev]; 1501 async = s->async; 1502 1503 /* are we locked? (ioctl lock) */ 1504 if (s->lock && s->lock != file) { 1505 dev_dbg(dev->class_dev, "subdevice locked\n"); 1506 return -EACCES; 1507 } 1508 1509 /* are we busy? */ 1510 if (s->busy) { 1511 dev_dbg(dev->class_dev, "subdevice busy\n"); 1512 return -EBUSY; 1513 } 1514 1515 /* make sure channel/gain list isn't too short */ 1516 if (cmd.chanlist_len < 1) { 1517 dev_dbg(dev->class_dev, "channel/gain list too short %u < 1\n", 1518 cmd.chanlist_len); 1519 return -EINVAL; 1520 } 1521 1522 async->cmd = cmd; 1523 async->cmd.data = NULL; 1524 1525 /* load channel/gain list */ 1526 ret = __comedi_get_user_chanlist(dev, s, user_chanlist, &async->cmd); 1527 if (ret) 1528 goto cleanup; 1529 1530 ret = s->do_cmdtest(dev, s, &async->cmd); 1531 1532 if (async->cmd.flags & CMDF_BOGUS || ret) { 1533 dev_dbg(dev->class_dev, "test returned %d\n", ret); 1534 cmd = async->cmd; 1535 /* restore chanlist pointer before copying back */ 1536 cmd.chanlist = (unsigned int __force *)user_chanlist; 1537 cmd.data = NULL; 1538 if (copy_to_user(arg, &cmd, sizeof(cmd))) { 1539 dev_dbg(dev->class_dev, "fault writing cmd\n"); 1540 ret = -EFAULT; 1541 goto cleanup; 1542 } 1543 ret = -EAGAIN; 1544 goto cleanup; 1545 } 1546 1547 if (!async->prealloc_bufsz) { 1548 ret = -ENOMEM; 1549 dev_dbg(dev->class_dev, "no buffer (?)\n"); 1550 goto cleanup; 1551 } 1552 1553 comedi_buf_reset(s); 1554 1555 async->cb_mask = 1556 COMEDI_CB_EOA | COMEDI_CB_BLOCK | COMEDI_CB_ERROR | 1557 COMEDI_CB_OVERFLOW; 1558 if (async->cmd.flags & CMDF_WAKE_EOS) 1559 async->cb_mask |= COMEDI_CB_EOS; 1560 1561 comedi_set_subdevice_runflags(s, SRF_ERROR | SRF_RUNNING, SRF_RUNNING); 1562 1563 /* set s->busy _after_ setting SRF_RUNNING flag to avoid race with 1564 * comedi_read() or comedi_write() */ 1565 s->busy = file; 1566 ret = s->do_cmd(dev, s); 1567 if (ret == 0) 1568 return 0; 1569 1570cleanup: 1571 do_become_nonbusy(dev, s); 1572 1573 return ret; 1574} 1575 1576/* 1577 COMEDI_CMDTEST 1578 command testing ioctl 1579 1580 arg: 1581 pointer to cmd structure 1582 1583 reads: 1584 cmd structure at arg 1585 channel/range list 1586 1587 writes: 1588 modified cmd structure at arg 1589 1590*/ 1591static int do_cmdtest_ioctl(struct comedi_device *dev, 1592 struct comedi_cmd __user *arg, void *file) 1593{ 1594 struct comedi_cmd cmd; 1595 struct comedi_subdevice *s; 1596 unsigned int __user *user_chanlist; 1597 int ret; 1598 1599 /* get the user's cmd and do some simple validation */ 1600 ret = __comedi_get_user_cmd(dev, arg, &cmd); 1601 if (ret) 1602 return ret; 1603 1604 /* save user's chanlist pointer so it can be restored later */ 1605 user_chanlist = (unsigned int __user *)cmd.chanlist; 1606 1607 s = &dev->subdevices[cmd.subdev]; 1608 1609 /* user_chanlist can be NULL for COMEDI_CMDTEST ioctl */ 1610 if (user_chanlist) { 1611 /* load channel/gain list */ 1612 ret = __comedi_get_user_chanlist(dev, s, user_chanlist, &cmd); 1613 if (ret) 1614 return ret; 1615 } 1616 1617 ret = s->do_cmdtest(dev, s, &cmd); 1618 1619 kfree(cmd.chanlist); /* free kernel copy of user chanlist */ 1620 1621 /* restore chanlist pointer before copying back */ 1622 cmd.chanlist = (unsigned int __force *)user_chanlist; 1623 1624 if (copy_to_user(arg, &cmd, sizeof(cmd))) { 1625 dev_dbg(dev->class_dev, "bad cmd address\n"); 1626 ret = -EFAULT; 1627 } 1628 1629 return ret; 1630} 1631 1632/* 1633 COMEDI_LOCK 1634 lock subdevice 1635 1636 arg: 1637 subdevice number 1638 1639 reads: 1640 none 1641 1642 writes: 1643 none 1644 1645*/ 1646 1647static int do_lock_ioctl(struct comedi_device *dev, unsigned long arg, 1648 void *file) 1649{ 1650 int ret = 0; 1651 unsigned long flags; 1652 struct comedi_subdevice *s; 1653 1654 if (arg >= dev->n_subdevices) 1655 return -EINVAL; 1656 s = &dev->subdevices[arg]; 1657 1658 spin_lock_irqsave(&s->spin_lock, flags); 1659 if (s->busy || s->lock) 1660 ret = -EBUSY; 1661 else 1662 s->lock = file; 1663 spin_unlock_irqrestore(&s->spin_lock, flags); 1664 1665 return ret; 1666} 1667 1668/* 1669 COMEDI_UNLOCK 1670 unlock subdevice 1671 1672 arg: 1673 subdevice number 1674 1675 reads: 1676 none 1677 1678 writes: 1679 none 1680 1681 This function isn't protected by the semaphore, since 1682 we already own the lock. 1683*/ 1684static int do_unlock_ioctl(struct comedi_device *dev, unsigned long arg, 1685 void *file) 1686{ 1687 struct comedi_subdevice *s; 1688 1689 if (arg >= dev->n_subdevices) 1690 return -EINVAL; 1691 s = &dev->subdevices[arg]; 1692 1693 if (s->busy) 1694 return -EBUSY; 1695 1696 if (s->lock && s->lock != file) 1697 return -EACCES; 1698 1699 if (s->lock == file) 1700 s->lock = NULL; 1701 1702 return 0; 1703} 1704 1705/* 1706 COMEDI_CANCEL 1707 cancel acquisition ioctl 1708 1709 arg: 1710 subdevice number 1711 1712 reads: 1713 nothing 1714 1715 writes: 1716 nothing 1717 1718*/ 1719static int do_cancel_ioctl(struct comedi_device *dev, unsigned long arg, 1720 void *file) 1721{ 1722 struct comedi_subdevice *s; 1723 int ret; 1724 1725 if (arg >= dev->n_subdevices) 1726 return -EINVAL; 1727 s = &dev->subdevices[arg]; 1728 if (s->async == NULL) 1729 return -EINVAL; 1730 1731 if (!s->busy) 1732 return 0; 1733 1734 if (s->busy != file) 1735 return -EBUSY; 1736 1737 ret = do_cancel(dev, s); 1738 1739 return ret; 1740} 1741 1742/* 1743 COMEDI_POLL ioctl 1744 instructs driver to synchronize buffers 1745 1746 arg: 1747 subdevice number 1748 1749 reads: 1750 nothing 1751 1752 writes: 1753 nothing 1754 1755*/ 1756static int do_poll_ioctl(struct comedi_device *dev, unsigned long arg, 1757 void *file) 1758{ 1759 struct comedi_subdevice *s; 1760 1761 if (arg >= dev->n_subdevices) 1762 return -EINVAL; 1763 s = &dev->subdevices[arg]; 1764 1765 if (!s->busy) 1766 return 0; 1767 1768 if (s->busy != file) 1769 return -EBUSY; 1770 1771 if (s->poll) 1772 return s->poll(dev, s); 1773 1774 return -EINVAL; 1775} 1776 1777static long comedi_unlocked_ioctl(struct file *file, unsigned int cmd, 1778 unsigned long arg) 1779{ 1780 const unsigned minor = iminor(file_inode(file)); 1781 struct comedi_device *dev = file->private_data; 1782 int rc; 1783 1784 mutex_lock(&dev->mutex); 1785 1786 /* Device config is special, because it must work on 1787 * an unconfigured device. */ 1788 if (cmd == COMEDI_DEVCONFIG) { 1789 if (minor >= COMEDI_NUM_BOARD_MINORS) { 1790 /* Device config not appropriate on non-board minors. */ 1791 rc = -ENOTTY; 1792 goto done; 1793 } 1794 rc = do_devconfig_ioctl(dev, 1795 (struct comedi_devconfig __user *)arg); 1796 if (rc == 0) { 1797 if (arg == 0 && 1798 dev->minor >= comedi_num_legacy_minors) { 1799 /* Successfully unconfigured a dynamically 1800 * allocated device. Try and remove it. */ 1801 if (comedi_clear_board_dev(dev)) { 1802 mutex_unlock(&dev->mutex); 1803 comedi_free_board_dev(dev); 1804 return rc; 1805 } 1806 } 1807 } 1808 goto done; 1809 } 1810 1811 if (!dev->attached) { 1812 dev_dbg(dev->class_dev, "no driver attached\n"); 1813 rc = -ENODEV; 1814 goto done; 1815 } 1816 1817 switch (cmd) { 1818 case COMEDI_BUFCONFIG: 1819 rc = do_bufconfig_ioctl(dev, 1820 (struct comedi_bufconfig __user *)arg); 1821 break; 1822 case COMEDI_DEVINFO: 1823 rc = do_devinfo_ioctl(dev, (struct comedi_devinfo __user *)arg, 1824 file); 1825 break; 1826 case COMEDI_SUBDINFO: 1827 rc = do_subdinfo_ioctl(dev, 1828 (struct comedi_subdinfo __user *)arg, 1829 file); 1830 break; 1831 case COMEDI_CHANINFO: 1832 rc = do_chaninfo_ioctl(dev, (void __user *)arg); 1833 break; 1834 case COMEDI_RANGEINFO: 1835 rc = do_rangeinfo_ioctl(dev, (void __user *)arg); 1836 break; 1837 case COMEDI_BUFINFO: 1838 rc = do_bufinfo_ioctl(dev, 1839 (struct comedi_bufinfo __user *)arg, 1840 file); 1841 break; 1842 case COMEDI_LOCK: 1843 rc = do_lock_ioctl(dev, arg, file); 1844 break; 1845 case COMEDI_UNLOCK: 1846 rc = do_unlock_ioctl(dev, arg, file); 1847 break; 1848 case COMEDI_CANCEL: 1849 rc = do_cancel_ioctl(dev, arg, file); 1850 break; 1851 case COMEDI_CMD: 1852 rc = do_cmd_ioctl(dev, (struct comedi_cmd __user *)arg, file); 1853 break; 1854 case COMEDI_CMDTEST: 1855 rc = do_cmdtest_ioctl(dev, (struct comedi_cmd __user *)arg, 1856 file); 1857 break; 1858 case COMEDI_INSNLIST: 1859 rc = do_insnlist_ioctl(dev, 1860 (struct comedi_insnlist __user *)arg, 1861 file); 1862 break; 1863 case COMEDI_INSN: 1864 rc = do_insn_ioctl(dev, (struct comedi_insn __user *)arg, 1865 file); 1866 break; 1867 case COMEDI_POLL: 1868 rc = do_poll_ioctl(dev, arg, file); 1869 break; 1870 default: 1871 rc = -ENOTTY; 1872 break; 1873 } 1874 1875done: 1876 mutex_unlock(&dev->mutex); 1877 return rc; 1878} 1879 1880static void comedi_vm_open(struct vm_area_struct *area) 1881{ 1882 struct comedi_buf_map *bm; 1883 1884 bm = area->vm_private_data; 1885 comedi_buf_map_get(bm); 1886} 1887 1888static void comedi_vm_close(struct vm_area_struct *area) 1889{ 1890 struct comedi_buf_map *bm; 1891 1892 bm = area->vm_private_data; 1893 comedi_buf_map_put(bm); 1894} 1895 1896static struct vm_operations_struct comedi_vm_ops = { 1897 .open = comedi_vm_open, 1898 .close = comedi_vm_close, 1899}; 1900 1901static int comedi_mmap(struct file *file, struct vm_area_struct *vma) 1902{ 1903 const unsigned minor = iminor(file_inode(file)); 1904 struct comedi_device *dev = file->private_data; 1905 struct comedi_subdevice *s; 1906 struct comedi_async *async; 1907 struct comedi_buf_map *bm = NULL; 1908 unsigned long start = vma->vm_start; 1909 unsigned long size; 1910 int n_pages; 1911 int i; 1912 int retval; 1913 1914 /* 1915 * 'trylock' avoids circular dependency with current->mm->mmap_sem 1916 * and down-reading &dev->attach_lock should normally succeed without 1917 * contention unless the device is in the process of being attached 1918 * or detached. 1919 */ 1920 if (!down_read_trylock(&dev->attach_lock)) 1921 return -EAGAIN; 1922 1923 if (!dev->attached) { 1924 dev_dbg(dev->class_dev, "no driver attached\n"); 1925 retval = -ENODEV; 1926 goto done; 1927 } 1928 1929 if (vma->vm_flags & VM_WRITE) 1930 s = comedi_write_subdevice(dev, minor); 1931 else 1932 s = comedi_read_subdevice(dev, minor); 1933 if (!s) { 1934 retval = -EINVAL; 1935 goto done; 1936 } 1937 1938 async = s->async; 1939 if (!async) { 1940 retval = -EINVAL; 1941 goto done; 1942 } 1943 1944 if (vma->vm_pgoff != 0) { 1945 dev_dbg(dev->class_dev, "mmap() offset must be 0.\n"); 1946 retval = -EINVAL; 1947 goto done; 1948 } 1949 1950 size = vma->vm_end - vma->vm_start; 1951 if (size > async->prealloc_bufsz) { 1952 retval = -EFAULT; 1953 goto done; 1954 } 1955 if (size & (~PAGE_MASK)) { 1956 retval = -EFAULT; 1957 goto done; 1958 } 1959 1960 n_pages = size >> PAGE_SHIFT; 1961 1962 /* get reference to current buf map (if any) */ 1963 bm = comedi_buf_map_from_subdev_get(s); 1964 if (!bm || n_pages > bm->n_pages) { 1965 retval = -EINVAL; 1966 goto done; 1967 } 1968 for (i = 0; i < n_pages; ++i) { 1969 struct comedi_buf_page *buf = &bm->page_list[i]; 1970 1971 if (remap_pfn_range(vma, start, 1972 page_to_pfn(virt_to_page(buf->virt_addr)), 1973 PAGE_SIZE, PAGE_SHARED)) { 1974 retval = -EAGAIN; 1975 goto done; 1976 } 1977 start += PAGE_SIZE; 1978 } 1979 1980 vma->vm_ops = &comedi_vm_ops; 1981 vma->vm_private_data = bm; 1982 1983 vma->vm_ops->open(vma); 1984 1985 retval = 0; 1986done: 1987 up_read(&dev->attach_lock); 1988 comedi_buf_map_put(bm); /* put reference to buf map - okay if NULL */ 1989 return retval; 1990} 1991 1992static unsigned int comedi_poll(struct file *file, poll_table *wait) 1993{ 1994 unsigned int mask = 0; 1995 const unsigned minor = iminor(file_inode(file)); 1996 struct comedi_device *dev = file->private_data; 1997 struct comedi_subdevice *s; 1998 1999 mutex_lock(&dev->mutex); 2000 2001 if (!dev->attached) { 2002 dev_dbg(dev->class_dev, "no driver attached\n"); 2003 goto done; 2004 } 2005 2006 s = comedi_read_subdevice(dev, minor); 2007 if (s && s->async) { 2008 poll_wait(file, &s->async->wait_head, wait); 2009 if (!s->busy || !comedi_is_subdevice_running(s) || 2010 comedi_buf_read_n_available(s) > 0) 2011 mask |= POLLIN | POLLRDNORM; 2012 } 2013 2014 s = comedi_write_subdevice(dev, minor); 2015 if (s && s->async) { 2016 unsigned int bps = bytes_per_sample(s); 2017 2018 poll_wait(file, &s->async->wait_head, wait); 2019 comedi_buf_write_alloc(s, s->async->prealloc_bufsz); 2020 if (!s->busy || !comedi_is_subdevice_running(s) || 2021 comedi_buf_write_n_allocated(s) >= bps) 2022 mask |= POLLOUT | POLLWRNORM; 2023 } 2024 2025done: 2026 mutex_unlock(&dev->mutex); 2027 return mask; 2028} 2029 2030static ssize_t comedi_write(struct file *file, const char __user *buf, 2031 size_t nbytes, loff_t *offset) 2032{ 2033 struct comedi_subdevice *s; 2034 struct comedi_async *async; 2035 int n, m, count = 0, retval = 0; 2036 DECLARE_WAITQUEUE(wait, current); 2037 const unsigned minor = iminor(file_inode(file)); 2038 struct comedi_device *dev = file->private_data; 2039 bool on_wait_queue = false; 2040 bool attach_locked; 2041 unsigned int old_detach_count; 2042 2043 /* Protect against device detachment during operation. */ 2044 down_read(&dev->attach_lock); 2045 attach_locked = true; 2046 old_detach_count = dev->detach_count; 2047 2048 if (!dev->attached) { 2049 dev_dbg(dev->class_dev, "no driver attached\n"); 2050 retval = -ENODEV; 2051 goto out; 2052 } 2053 2054 s = comedi_write_subdevice(dev, minor); 2055 if (!s || !s->async) { 2056 retval = -EIO; 2057 goto out; 2058 } 2059 2060 async = s->async; 2061 2062 if (!s->busy || !nbytes) 2063 goto out; 2064 if (s->busy != file) { 2065 retval = -EACCES; 2066 goto out; 2067 } 2068 2069 add_wait_queue(&async->wait_head, &wait); 2070 on_wait_queue = true; 2071 while (nbytes > 0 && !retval) { 2072 set_current_state(TASK_INTERRUPTIBLE); 2073 2074 if (!comedi_is_subdevice_running(s)) { 2075 if (count == 0) { 2076 struct comedi_subdevice *new_s; 2077 2078 if (comedi_is_subdevice_in_error(s)) 2079 retval = -EPIPE; 2080 else 2081 retval = 0; 2082 /* 2083 * To avoid deadlock, cannot acquire dev->mutex 2084 * while dev->attach_lock is held. Need to 2085 * remove task from the async wait queue before 2086 * releasing dev->attach_lock, as it might not 2087 * be valid afterwards. 2088 */ 2089 remove_wait_queue(&async->wait_head, &wait); 2090 on_wait_queue = false; 2091 up_read(&dev->attach_lock); 2092 attach_locked = false; 2093 mutex_lock(&dev->mutex); 2094 /* 2095 * Become non-busy unless things have changed 2096 * behind our back. Checking dev->detach_count 2097 * is unchanged ought to be sufficient (unless 2098 * there have been 2**32 detaches in the 2099 * meantime!), but check the subdevice pointer 2100 * as well just in case. 2101 */ 2102 new_s = comedi_write_subdevice(dev, minor); 2103 if (dev->attached && 2104 old_detach_count == dev->detach_count && 2105 s == new_s && new_s->async == async) 2106 do_become_nonbusy(dev, s); 2107 mutex_unlock(&dev->mutex); 2108 } 2109 break; 2110 } 2111 2112 n = nbytes; 2113 2114 m = n; 2115 if (async->buf_write_ptr + m > async->prealloc_bufsz) 2116 m = async->prealloc_bufsz - async->buf_write_ptr; 2117 comedi_buf_write_alloc(s, async->prealloc_bufsz); 2118 if (m > comedi_buf_write_n_allocated(s)) 2119 m = comedi_buf_write_n_allocated(s); 2120 if (m < n) 2121 n = m; 2122 2123 if (n == 0) { 2124 if (file->f_flags & O_NONBLOCK) { 2125 retval = -EAGAIN; 2126 break; 2127 } 2128 schedule(); 2129 if (signal_pending(current)) { 2130 retval = -ERESTARTSYS; 2131 break; 2132 } 2133 if (!s->busy) 2134 break; 2135 if (s->busy != file) { 2136 retval = -EACCES; 2137 break; 2138 } 2139 continue; 2140 } 2141 2142 m = copy_from_user(async->prealloc_buf + async->buf_write_ptr, 2143 buf, n); 2144 if (m) { 2145 n -= m; 2146 retval = -EFAULT; 2147 } 2148 comedi_buf_write_free(s, n); 2149 2150 count += n; 2151 nbytes -= n; 2152 2153 buf += n; 2154 break; /* makes device work like a pipe */ 2155 } 2156out: 2157 if (on_wait_queue) 2158 remove_wait_queue(&async->wait_head, &wait); 2159 set_current_state(TASK_RUNNING); 2160 if (attach_locked) 2161 up_read(&dev->attach_lock); 2162 2163 return count ? count : retval; 2164} 2165 2166static ssize_t comedi_read(struct file *file, char __user *buf, size_t nbytes, 2167 loff_t *offset) 2168{ 2169 struct comedi_subdevice *s; 2170 struct comedi_async *async; 2171 int n, m, count = 0, retval = 0; 2172 DECLARE_WAITQUEUE(wait, current); 2173 const unsigned minor = iminor(file_inode(file)); 2174 struct comedi_device *dev = file->private_data; 2175 unsigned int old_detach_count; 2176 bool become_nonbusy = false; 2177 bool attach_locked; 2178 2179 /* Protect against device detachment during operation. */ 2180 down_read(&dev->attach_lock); 2181 attach_locked = true; 2182 old_detach_count = dev->detach_count; 2183 2184 if (!dev->attached) { 2185 dev_dbg(dev->class_dev, "no driver attached\n"); 2186 retval = -ENODEV; 2187 goto out; 2188 } 2189 2190 s = comedi_read_subdevice(dev, minor); 2191 if (!s || !s->async) { 2192 retval = -EIO; 2193 goto out; 2194 } 2195 2196 async = s->async; 2197 if (!s->busy || !nbytes) 2198 goto out; 2199 if (s->busy != file) { 2200 retval = -EACCES; 2201 goto out; 2202 } 2203 2204 add_wait_queue(&async->wait_head, &wait); 2205 while (nbytes > 0 && !retval) { 2206 set_current_state(TASK_INTERRUPTIBLE); 2207 2208 n = nbytes; 2209 2210 m = comedi_buf_read_n_available(s); 2211 if (async->buf_read_ptr + m > async->prealloc_bufsz) 2212 m = async->prealloc_bufsz - async->buf_read_ptr; 2213 if (m < n) 2214 n = m; 2215 2216 if (n == 0) { 2217 if (!comedi_is_subdevice_running(s)) { 2218 if (comedi_is_subdevice_in_error(s)) 2219 retval = -EPIPE; 2220 else 2221 retval = 0; 2222 become_nonbusy = true; 2223 break; 2224 } 2225 if (file->f_flags & O_NONBLOCK) { 2226 retval = -EAGAIN; 2227 break; 2228 } 2229 schedule(); 2230 if (signal_pending(current)) { 2231 retval = -ERESTARTSYS; 2232 break; 2233 } 2234 if (!s->busy) { 2235 retval = 0; 2236 break; 2237 } 2238 if (s->busy != file) { 2239 retval = -EACCES; 2240 break; 2241 } 2242 continue; 2243 } 2244 m = copy_to_user(buf, async->prealloc_buf + 2245 async->buf_read_ptr, n); 2246 if (m) { 2247 n -= m; 2248 retval = -EFAULT; 2249 } 2250 2251 comedi_buf_read_alloc(s, n); 2252 comedi_buf_read_free(s, n); 2253 2254 count += n; 2255 nbytes -= n; 2256 2257 buf += n; 2258 break; /* makes device work like a pipe */ 2259 } 2260 remove_wait_queue(&async->wait_head, &wait); 2261 set_current_state(TASK_RUNNING); 2262 if (become_nonbusy || comedi_is_subdevice_idle(s)) { 2263 struct comedi_subdevice *new_s; 2264 2265 /* 2266 * To avoid deadlock, cannot acquire dev->mutex 2267 * while dev->attach_lock is held. 2268 */ 2269 up_read(&dev->attach_lock); 2270 attach_locked = false; 2271 mutex_lock(&dev->mutex); 2272 /* 2273 * Check device hasn't become detached behind our back. 2274 * Checking dev->detach_count is unchanged ought to be 2275 * sufficient (unless there have been 2**32 detaches in the 2276 * meantime!), but check the subdevice pointer as well just in 2277 * case. 2278 */ 2279 new_s = comedi_read_subdevice(dev, minor); 2280 if (dev->attached && old_detach_count == dev->detach_count && 2281 s == new_s && new_s->async == async) { 2282 if (become_nonbusy || comedi_buf_n_bytes_ready(s) == 0) 2283 do_become_nonbusy(dev, s); 2284 } 2285 mutex_unlock(&dev->mutex); 2286 } 2287out: 2288 if (attach_locked) 2289 up_read(&dev->attach_lock); 2290 2291 return count ? count : retval; 2292} 2293 2294static int comedi_open(struct inode *inode, struct file *file) 2295{ 2296 const unsigned minor = iminor(inode); 2297 struct comedi_device *dev = comedi_dev_get_from_minor(minor); 2298 int rc; 2299 2300 if (!dev) { 2301 pr_debug("invalid minor number\n"); 2302 return -ENODEV; 2303 } 2304 2305 mutex_lock(&dev->mutex); 2306 if (!dev->attached && !capable(CAP_NET_ADMIN)) { 2307 dev_dbg(dev->class_dev, "not attached and not CAP_NET_ADMIN\n"); 2308 rc = -ENODEV; 2309 goto out; 2310 } 2311 if (dev->attached && dev->use_count == 0) { 2312 if (!try_module_get(dev->driver->module)) { 2313 rc = -ENOSYS; 2314 goto out; 2315 } 2316 if (dev->open) { 2317 rc = dev->open(dev); 2318 if (rc < 0) { 2319 module_put(dev->driver->module); 2320 goto out; 2321 } 2322 } 2323 } 2324 2325 dev->use_count++; 2326 file->private_data = dev; 2327 rc = 0; 2328 2329out: 2330 mutex_unlock(&dev->mutex); 2331 if (rc) 2332 comedi_dev_put(dev); 2333 return rc; 2334} 2335 2336static int comedi_fasync(int fd, struct file *file, int on) 2337{ 2338 struct comedi_device *dev = file->private_data; 2339 2340 return fasync_helper(fd, file, on, &dev->async_queue); 2341} 2342 2343static int comedi_close(struct inode *inode, struct file *file) 2344{ 2345 struct comedi_device *dev = file->private_data; 2346 struct comedi_subdevice *s = NULL; 2347 int i; 2348 2349 mutex_lock(&dev->mutex); 2350 2351 if (dev->subdevices) { 2352 for (i = 0; i < dev->n_subdevices; i++) { 2353 s = &dev->subdevices[i]; 2354 2355 if (s->busy == file) 2356 do_cancel(dev, s); 2357 if (s->lock == file) 2358 s->lock = NULL; 2359 } 2360 } 2361 if (dev->attached && dev->use_count == 1) { 2362 if (dev->close) 2363 dev->close(dev); 2364 module_put(dev->driver->module); 2365 } 2366 2367 dev->use_count--; 2368 2369 mutex_unlock(&dev->mutex); 2370 comedi_dev_put(dev); 2371 2372 return 0; 2373} 2374 2375static const struct file_operations comedi_fops = { 2376 .owner = THIS_MODULE, 2377 .unlocked_ioctl = comedi_unlocked_ioctl, 2378 .compat_ioctl = comedi_compat_ioctl, 2379 .open = comedi_open, 2380 .release = comedi_close, 2381 .read = comedi_read, 2382 .write = comedi_write, 2383 .mmap = comedi_mmap, 2384 .poll = comedi_poll, 2385 .fasync = comedi_fasync, 2386 .llseek = noop_llseek, 2387}; 2388 2389void comedi_event(struct comedi_device *dev, struct comedi_subdevice *s) 2390{ 2391 struct comedi_async *async = s->async; 2392 unsigned runflags = 0; 2393 unsigned runflags_mask = 0; 2394 2395 if (!comedi_is_subdevice_running(s)) 2396 return; 2397 2398 if (s-> 2399 async->events & (COMEDI_CB_EOA | COMEDI_CB_ERROR | 2400 COMEDI_CB_OVERFLOW)) { 2401 runflags_mask |= SRF_RUNNING; 2402 } 2403 /* remember if an error event has occurred, so an error 2404 * can be returned the next time the user does a read() */ 2405 if (s->async->events & (COMEDI_CB_ERROR | COMEDI_CB_OVERFLOW)) { 2406 runflags_mask |= SRF_ERROR; 2407 runflags |= SRF_ERROR; 2408 } 2409 if (runflags_mask) { 2410 /*sets SRF_ERROR and SRF_RUNNING together atomically */ 2411 comedi_set_subdevice_runflags(s, runflags_mask, runflags); 2412 } 2413 2414 if (async->cb_mask & s->async->events) { 2415 wake_up_interruptible(&async->wait_head); 2416 if (s->subdev_flags & SDF_CMD_READ) 2417 kill_fasync(&dev->async_queue, SIGIO, POLL_IN); 2418 if (s->subdev_flags & SDF_CMD_WRITE) 2419 kill_fasync(&dev->async_queue, SIGIO, POLL_OUT); 2420 } 2421 s->async->events = 0; 2422} 2423EXPORT_SYMBOL_GPL(comedi_event); 2424 2425/* Note: the ->mutex is pre-locked on successful return */ 2426struct comedi_device *comedi_alloc_board_minor(struct device *hardware_device) 2427{ 2428 struct comedi_device *dev; 2429 struct device *csdev; 2430 unsigned i; 2431 2432 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 2433 if (dev == NULL) 2434 return ERR_PTR(-ENOMEM); 2435 comedi_device_init(dev); 2436 comedi_set_hw_dev(dev, hardware_device); 2437 mutex_lock(&dev->mutex); 2438 mutex_lock(&comedi_board_minor_table_lock); 2439 for (i = hardware_device ? comedi_num_legacy_minors : 0; 2440 i < COMEDI_NUM_BOARD_MINORS; ++i) { 2441 if (comedi_board_minor_table[i] == NULL) { 2442 comedi_board_minor_table[i] = dev; 2443 break; 2444 } 2445 } 2446 mutex_unlock(&comedi_board_minor_table_lock); 2447 if (i == COMEDI_NUM_BOARD_MINORS) { 2448 mutex_unlock(&dev->mutex); 2449 comedi_device_cleanup(dev); 2450 comedi_dev_put(dev); 2451 pr_err("ran out of minor numbers for board device files\n"); 2452 return ERR_PTR(-EBUSY); 2453 } 2454 dev->minor = i; 2455 csdev = device_create(comedi_class, hardware_device, 2456 MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i", i); 2457 if (!IS_ERR(csdev)) 2458 dev->class_dev = get_device(csdev); 2459 2460 /* Note: dev->mutex needs to be unlocked by the caller. */ 2461 return dev; 2462} 2463 2464static void comedi_free_board_minor(unsigned minor) 2465{ 2466 BUG_ON(minor >= COMEDI_NUM_BOARD_MINORS); 2467 comedi_free_board_dev(comedi_clear_board_minor(minor)); 2468} 2469 2470void comedi_release_hardware_device(struct device *hardware_device) 2471{ 2472 int minor; 2473 struct comedi_device *dev; 2474 2475 for (minor = comedi_num_legacy_minors; minor < COMEDI_NUM_BOARD_MINORS; 2476 minor++) { 2477 mutex_lock(&comedi_board_minor_table_lock); 2478 dev = comedi_board_minor_table[minor]; 2479 if (dev && dev->hw_dev == hardware_device) { 2480 comedi_board_minor_table[minor] = NULL; 2481 mutex_unlock(&comedi_board_minor_table_lock); 2482 comedi_free_board_dev(dev); 2483 break; 2484 } 2485 mutex_unlock(&comedi_board_minor_table_lock); 2486 } 2487} 2488 2489int comedi_alloc_subdevice_minor(struct comedi_subdevice *s) 2490{ 2491 struct comedi_device *dev = s->device; 2492 struct device *csdev; 2493 unsigned i; 2494 2495 mutex_lock(&comedi_subdevice_minor_table_lock); 2496 for (i = 0; i < COMEDI_NUM_SUBDEVICE_MINORS; ++i) { 2497 if (comedi_subdevice_minor_table[i] == NULL) { 2498 comedi_subdevice_minor_table[i] = s; 2499 break; 2500 } 2501 } 2502 mutex_unlock(&comedi_subdevice_minor_table_lock); 2503 if (i == COMEDI_NUM_SUBDEVICE_MINORS) { 2504 pr_err("ran out of minor numbers for subdevice files\n"); 2505 return -EBUSY; 2506 } 2507 i += COMEDI_NUM_BOARD_MINORS; 2508 s->minor = i; 2509 csdev = device_create(comedi_class, dev->class_dev, 2510 MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i_subd%i", 2511 dev->minor, s->index); 2512 if (!IS_ERR(csdev)) 2513 s->class_dev = csdev; 2514 2515 return 0; 2516} 2517 2518void comedi_free_subdevice_minor(struct comedi_subdevice *s) 2519{ 2520 unsigned int i; 2521 2522 if (s == NULL) 2523 return; 2524 if (s->minor < 0) 2525 return; 2526 2527 BUG_ON(s->minor >= COMEDI_NUM_MINORS); 2528 BUG_ON(s->minor < COMEDI_NUM_BOARD_MINORS); 2529 2530 i = s->minor - COMEDI_NUM_BOARD_MINORS; 2531 mutex_lock(&comedi_subdevice_minor_table_lock); 2532 if (s == comedi_subdevice_minor_table[i]) 2533 comedi_subdevice_minor_table[i] = NULL; 2534 mutex_unlock(&comedi_subdevice_minor_table_lock); 2535 if (s->class_dev) { 2536 device_destroy(comedi_class, MKDEV(COMEDI_MAJOR, s->minor)); 2537 s->class_dev = NULL; 2538 } 2539} 2540 2541static void comedi_cleanup_board_minors(void) 2542{ 2543 unsigned i; 2544 2545 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) 2546 comedi_free_board_minor(i); 2547} 2548 2549static int __init comedi_init(void) 2550{ 2551 int i; 2552 int retval; 2553 2554 pr_info("version " COMEDI_RELEASE " - http://www.comedi.org\n"); 2555 2556 if (comedi_num_legacy_minors < 0 || 2557 comedi_num_legacy_minors > COMEDI_NUM_BOARD_MINORS) { 2558 pr_err("invalid value for module parameter \"comedi_num_legacy_minors\". Valid values are 0 through %i.\n", 2559 COMEDI_NUM_BOARD_MINORS); 2560 return -EINVAL; 2561 } 2562 2563 retval = register_chrdev_region(MKDEV(COMEDI_MAJOR, 0), 2564 COMEDI_NUM_MINORS, "comedi"); 2565 if (retval) 2566 return -EIO; 2567 cdev_init(&comedi_cdev, &comedi_fops); 2568 comedi_cdev.owner = THIS_MODULE; 2569 2570 retval = kobject_set_name(&comedi_cdev.kobj, "comedi"); 2571 if (retval) { 2572 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0), 2573 COMEDI_NUM_MINORS); 2574 return retval; 2575 } 2576 2577 if (cdev_add(&comedi_cdev, MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS)) { 2578 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0), 2579 COMEDI_NUM_MINORS); 2580 return -EIO; 2581 } 2582 comedi_class = class_create(THIS_MODULE, "comedi"); 2583 if (IS_ERR(comedi_class)) { 2584 pr_err("failed to create class\n"); 2585 cdev_del(&comedi_cdev); 2586 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0), 2587 COMEDI_NUM_MINORS); 2588 return PTR_ERR(comedi_class); 2589 } 2590 2591 comedi_class->dev_groups = comedi_dev_groups; 2592 2593 /* XXX requires /proc interface */ 2594 comedi_proc_init(); 2595 2596 /* create devices files for legacy/manual use */ 2597 for (i = 0; i < comedi_num_legacy_minors; i++) { 2598 struct comedi_device *dev; 2599 2600 dev = comedi_alloc_board_minor(NULL); 2601 if (IS_ERR(dev)) { 2602 comedi_cleanup_board_minors(); 2603 cdev_del(&comedi_cdev); 2604 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0), 2605 COMEDI_NUM_MINORS); 2606 return PTR_ERR(dev); 2607 } 2608 /* comedi_alloc_board_minor() locked the mutex */ 2609 mutex_unlock(&dev->mutex); 2610 } 2611 2612 return 0; 2613} 2614module_init(comedi_init); 2615 2616static void __exit comedi_cleanup(void) 2617{ 2618 int i; 2619 2620 comedi_cleanup_board_minors(); 2621 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; ++i) 2622 BUG_ON(comedi_board_minor_table[i]); 2623 for (i = 0; i < COMEDI_NUM_SUBDEVICE_MINORS; ++i) 2624 BUG_ON(comedi_subdevice_minor_table[i]); 2625 2626 class_destroy(comedi_class); 2627 cdev_del(&comedi_cdev); 2628 unregister_chrdev_region(MKDEV(COMEDI_MAJOR, 0), COMEDI_NUM_MINORS); 2629 2630 comedi_proc_cleanup(); 2631} 2632module_exit(comedi_cleanup); 2633 2634MODULE_AUTHOR("http://www.comedi.org"); 2635MODULE_DESCRIPTION("Comedi core module"); 2636MODULE_LICENSE("GPL"); 2637