openprom.c revision 55929332c92e5d34d65a8f784604c92677ea3e15
1/* 2 * Linux/SPARC PROM Configuration Driver 3 * Copyright (C) 1996 Thomas K. Dyas (tdyas@noc.rutgers.edu) 4 * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be) 5 * 6 * This character device driver allows user programs to access the 7 * PROM device tree. It is compatible with the SunOS /dev/openprom 8 * driver and the NetBSD /dev/openprom driver. The SunOS eeprom 9 * utility works without any modifications. 10 * 11 * The driver uses a minor number under the misc device major. The 12 * file read/write mode determines the type of access to the PROM. 13 * Interrupts are disabled whenever the driver calls into the PROM for 14 * sanity's sake. 15 */ 16 17/* This program is free software; you can redistribute it and/or 18 * modify it under the terms of the GNU General Public License as 19 * published by the Free Software Foundation; either version 2 of the 20 * License, or (at your option) any later version. 21 * 22 * This program is distributed in the hope that it will be useful, but 23 * WITHOUT ANY WARRANTY; without even the implied warranty of 24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 25 * General Public License for more details. 26 * 27 * You should have received a copy of the GNU General Public License 28 * along with this program; if not, write to the Free Software 29 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 30 */ 31 32#include <linux/module.h> 33#include <linux/kernel.h> 34#include <linux/errno.h> 35#include <linux/slab.h> 36#include <linux/smp_lock.h> 37#include <linux/string.h> 38#include <linux/miscdevice.h> 39#include <linux/init.h> 40#include <linux/fs.h> 41#include <asm/oplib.h> 42#include <asm/prom.h> 43#include <asm/system.h> 44#include <asm/uaccess.h> 45#include <asm/openpromio.h> 46#ifdef CONFIG_PCI 47#include <linux/pci.h> 48#endif 49 50MODULE_AUTHOR("Thomas K. Dyas (tdyas@noc.rutgers.edu) and Eddie C. Dost (ecd@skynet.be)"); 51MODULE_DESCRIPTION("OPENPROM Configuration Driver"); 52MODULE_LICENSE("GPL"); 53MODULE_VERSION("1.0"); 54MODULE_ALIAS_MISCDEV(SUN_OPENPROM_MINOR); 55 56/* Private data kept by the driver for each descriptor. */ 57typedef struct openprom_private_data 58{ 59 struct device_node *current_node; /* Current node for SunOS ioctls. */ 60 struct device_node *lastnode; /* Last valid node used by BSD ioctls. */ 61} DATA; 62 63/* ID of the PROM node containing all of the EEPROM options. */ 64static struct device_node *options_node; 65 66/* 67 * Copy an openpromio structure into kernel space from user space. 68 * This routine does error checking to make sure that all memory 69 * accesses are within bounds. A pointer to the allocated openpromio 70 * structure will be placed in "*opp_p". Return value is the length 71 * of the user supplied buffer. 72 */ 73static int copyin(struct openpromio __user *info, struct openpromio **opp_p) 74{ 75 unsigned int bufsize; 76 77 if (!info || !opp_p) 78 return -EFAULT; 79 80 if (get_user(bufsize, &info->oprom_size)) 81 return -EFAULT; 82 83 if (bufsize == 0) 84 return -EINVAL; 85 86 /* If the bufsize is too large, just limit it. 87 * Fix from Jason Rappleye. 88 */ 89 if (bufsize > OPROMMAXPARAM) 90 bufsize = OPROMMAXPARAM; 91 92 if (!(*opp_p = kzalloc(sizeof(int) + bufsize + 1, GFP_KERNEL))) 93 return -ENOMEM; 94 95 if (copy_from_user(&(*opp_p)->oprom_array, 96 &info->oprom_array, bufsize)) { 97 kfree(*opp_p); 98 return -EFAULT; 99 } 100 return bufsize; 101} 102 103static int getstrings(struct openpromio __user *info, struct openpromio **opp_p) 104{ 105 int n, bufsize; 106 char c; 107 108 if (!info || !opp_p) 109 return -EFAULT; 110 111 if (!(*opp_p = kzalloc(sizeof(int) + OPROMMAXPARAM + 1, GFP_KERNEL))) 112 return -ENOMEM; 113 114 (*opp_p)->oprom_size = 0; 115 116 n = bufsize = 0; 117 while ((n < 2) && (bufsize < OPROMMAXPARAM)) { 118 if (get_user(c, &info->oprom_array[bufsize])) { 119 kfree(*opp_p); 120 return -EFAULT; 121 } 122 if (c == '\0') 123 n++; 124 (*opp_p)->oprom_array[bufsize++] = c; 125 } 126 if (!n) { 127 kfree(*opp_p); 128 return -EINVAL; 129 } 130 return bufsize; 131} 132 133/* 134 * Copy an openpromio structure in kernel space back to user space. 135 */ 136static int copyout(void __user *info, struct openpromio *opp, int len) 137{ 138 if (copy_to_user(info, opp, len)) 139 return -EFAULT; 140 return 0; 141} 142 143static int opromgetprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize) 144{ 145 const void *pval; 146 int len; 147 148 if (!dp || 149 !(pval = of_get_property(dp, op->oprom_array, &len)) || 150 len <= 0 || len > bufsize) 151 return copyout(argp, op, sizeof(int)); 152 153 memcpy(op->oprom_array, pval, len); 154 op->oprom_array[len] = '\0'; 155 op->oprom_size = len; 156 157 return copyout(argp, op, sizeof(int) + bufsize); 158} 159 160static int opromnxtprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize) 161{ 162 struct property *prop; 163 int len; 164 165 if (!dp) 166 return copyout(argp, op, sizeof(int)); 167 if (op->oprom_array[0] == '\0') { 168 prop = dp->properties; 169 if (!prop) 170 return copyout(argp, op, sizeof(int)); 171 len = strlen(prop->name); 172 } else { 173 prop = of_find_property(dp, op->oprom_array, NULL); 174 175 if (!prop || 176 !prop->next || 177 (len = strlen(prop->next->name)) + 1 > bufsize) 178 return copyout(argp, op, sizeof(int)); 179 180 prop = prop->next; 181 } 182 183 memcpy(op->oprom_array, prop->name, len); 184 op->oprom_array[len] = '\0'; 185 op->oprom_size = ++len; 186 187 return copyout(argp, op, sizeof(int) + bufsize); 188} 189 190static int opromsetopt(struct device_node *dp, struct openpromio *op, int bufsize) 191{ 192 char *buf = op->oprom_array + strlen(op->oprom_array) + 1; 193 int len = op->oprom_array + bufsize - buf; 194 195 return of_set_property(options_node, op->oprom_array, buf, len); 196} 197 198static int opromnext(void __user *argp, unsigned int cmd, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data) 199{ 200 phandle ph; 201 202 BUILD_BUG_ON(sizeof(phandle) != sizeof(int)); 203 204 if (bufsize < sizeof(phandle)) 205 return -EINVAL; 206 207 ph = *((int *) op->oprom_array); 208 if (ph) { 209 dp = of_find_node_by_phandle(ph); 210 if (!dp) 211 return -EINVAL; 212 213 switch (cmd) { 214 case OPROMNEXT: 215 dp = dp->sibling; 216 break; 217 218 case OPROMCHILD: 219 dp = dp->child; 220 break; 221 222 case OPROMSETCUR: 223 default: 224 break; 225 }; 226 } else { 227 /* Sibling of node zero is the root node. */ 228 if (cmd != OPROMNEXT) 229 return -EINVAL; 230 231 dp = of_find_node_by_path("/"); 232 } 233 234 ph = 0; 235 if (dp) 236 ph = dp->phandle; 237 238 data->current_node = dp; 239 *((int *) op->oprom_array) = ph; 240 op->oprom_size = sizeof(phandle); 241 242 return copyout(argp, op, bufsize + sizeof(int)); 243} 244 245static int oprompci2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data) 246{ 247 int err = -EINVAL; 248 249 if (bufsize >= 2*sizeof(int)) { 250#ifdef CONFIG_PCI 251 struct pci_dev *pdev; 252 struct device_node *dp; 253 254 pdev = pci_get_bus_and_slot (((int *) op->oprom_array)[0], 255 ((int *) op->oprom_array)[1]); 256 257 dp = pci_device_to_OF_node(pdev); 258 data->current_node = dp; 259 *((int *)op->oprom_array) = dp->phandle; 260 op->oprom_size = sizeof(int); 261 err = copyout(argp, op, bufsize + sizeof(int)); 262 263 pci_dev_put(pdev); 264#endif 265 } 266 267 return err; 268} 269 270static int oprompath2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data) 271{ 272 phandle ph = 0; 273 274 dp = of_find_node_by_path(op->oprom_array); 275 if (dp) 276 ph = dp->phandle; 277 data->current_node = dp; 278 *((int *)op->oprom_array) = ph; 279 op->oprom_size = sizeof(int); 280 281 return copyout(argp, op, bufsize + sizeof(int)); 282} 283 284static int opromgetbootargs(void __user *argp, struct openpromio *op, int bufsize) 285{ 286 char *buf = saved_command_line; 287 int len = strlen(buf); 288 289 if (len > bufsize) 290 return -EINVAL; 291 292 strcpy(op->oprom_array, buf); 293 op->oprom_size = len; 294 295 return copyout(argp, op, bufsize + sizeof(int)); 296} 297 298/* 299 * SunOS and Solaris /dev/openprom ioctl calls. 300 */ 301static long openprom_sunos_ioctl(struct file * file, 302 unsigned int cmd, unsigned long arg, 303 struct device_node *dp) 304{ 305 DATA *data = file->private_data; 306 struct openpromio *opp = NULL; 307 int bufsize, error = 0; 308 static int cnt; 309 void __user *argp = (void __user *)arg; 310 311 if (cmd == OPROMSETOPT) 312 bufsize = getstrings(argp, &opp); 313 else 314 bufsize = copyin(argp, &opp); 315 316 if (bufsize < 0) 317 return bufsize; 318 319 lock_kernel(); 320 321 switch (cmd) { 322 case OPROMGETOPT: 323 case OPROMGETPROP: 324 error = opromgetprop(argp, dp, opp, bufsize); 325 break; 326 327 case OPROMNXTOPT: 328 case OPROMNXTPROP: 329 error = opromnxtprop(argp, dp, opp, bufsize); 330 break; 331 332 case OPROMSETOPT: 333 case OPROMSETOPT2: 334 error = opromsetopt(dp, opp, bufsize); 335 break; 336 337 case OPROMNEXT: 338 case OPROMCHILD: 339 case OPROMSETCUR: 340 error = opromnext(argp, cmd, dp, opp, bufsize, data); 341 break; 342 343 case OPROMPCI2NODE: 344 error = oprompci2node(argp, dp, opp, bufsize, data); 345 break; 346 347 case OPROMPATH2NODE: 348 error = oprompath2node(argp, dp, opp, bufsize, data); 349 break; 350 351 case OPROMGETBOOTARGS: 352 error = opromgetbootargs(argp, opp, bufsize); 353 break; 354 355 case OPROMU2P: 356 case OPROMGETCONS: 357 case OPROMGETFBNAME: 358 if (cnt++ < 10) 359 printk(KERN_INFO "openprom_sunos_ioctl: unimplemented ioctl\n"); 360 error = -EINVAL; 361 break; 362 default: 363 if (cnt++ < 10) 364 printk(KERN_INFO "openprom_sunos_ioctl: cmd 0x%X, arg 0x%lX\n", cmd, arg); 365 error = -EINVAL; 366 break; 367 } 368 369 kfree(opp); 370 unlock_kernel(); 371 372 return error; 373} 374 375static struct device_node *get_node(phandle n, DATA *data) 376{ 377 struct device_node *dp = of_find_node_by_phandle(n); 378 379 if (dp) 380 data->lastnode = dp; 381 382 return dp; 383} 384 385/* Copy in a whole string from userspace into kernelspace. */ 386static int copyin_string(char __user *user, size_t len, char **ptr) 387{ 388 char *tmp; 389 390 if ((ssize_t)len < 0 || (ssize_t)(len + 1) < 0) 391 return -EINVAL; 392 393 tmp = kmalloc(len + 1, GFP_KERNEL); 394 if (!tmp) 395 return -ENOMEM; 396 397 if (copy_from_user(tmp, user, len)) { 398 kfree(tmp); 399 return -EFAULT; 400 } 401 402 tmp[len] = '\0'; 403 404 *ptr = tmp; 405 406 return 0; 407} 408 409/* 410 * NetBSD /dev/openprom ioctl calls. 411 */ 412static int opiocget(void __user *argp, DATA *data) 413{ 414 struct opiocdesc op; 415 struct device_node *dp; 416 char *str; 417 const void *pval; 418 int err, len; 419 420 if (copy_from_user(&op, argp, sizeof(op))) 421 return -EFAULT; 422 423 dp = get_node(op.op_nodeid, data); 424 425 err = copyin_string(op.op_name, op.op_namelen, &str); 426 if (err) 427 return err; 428 429 pval = of_get_property(dp, str, &len); 430 err = 0; 431 if (!pval || len > op.op_buflen) { 432 err = -EINVAL; 433 } else { 434 op.op_buflen = len; 435 if (copy_to_user(argp, &op, sizeof(op)) || 436 copy_to_user(op.op_buf, pval, len)) 437 err = -EFAULT; 438 } 439 kfree(str); 440 441 return err; 442} 443 444static int opiocnextprop(void __user *argp, DATA *data) 445{ 446 struct opiocdesc op; 447 struct device_node *dp; 448 struct property *prop; 449 char *str; 450 int err, len; 451 452 if (copy_from_user(&op, argp, sizeof(op))) 453 return -EFAULT; 454 455 dp = get_node(op.op_nodeid, data); 456 if (!dp) 457 return -EINVAL; 458 459 err = copyin_string(op.op_name, op.op_namelen, &str); 460 if (err) 461 return err; 462 463 if (str[0] == '\0') { 464 prop = dp->properties; 465 } else { 466 prop = of_find_property(dp, str, NULL); 467 if (prop) 468 prop = prop->next; 469 } 470 kfree(str); 471 472 if (!prop) 473 len = 0; 474 else 475 len = prop->length; 476 477 if (len > op.op_buflen) 478 len = op.op_buflen; 479 480 if (copy_to_user(argp, &op, sizeof(op))) 481 return -EFAULT; 482 483 if (len && 484 copy_to_user(op.op_buf, prop->value, len)) 485 return -EFAULT; 486 487 return 0; 488} 489 490static int opiocset(void __user *argp, DATA *data) 491{ 492 struct opiocdesc op; 493 struct device_node *dp; 494 char *str, *tmp; 495 int err; 496 497 if (copy_from_user(&op, argp, sizeof(op))) 498 return -EFAULT; 499 500 dp = get_node(op.op_nodeid, data); 501 if (!dp) 502 return -EINVAL; 503 504 err = copyin_string(op.op_name, op.op_namelen, &str); 505 if (err) 506 return err; 507 508 err = copyin_string(op.op_buf, op.op_buflen, &tmp); 509 if (err) { 510 kfree(str); 511 return err; 512 } 513 514 err = of_set_property(dp, str, tmp, op.op_buflen); 515 516 kfree(str); 517 kfree(tmp); 518 519 return err; 520} 521 522static int opiocgetnext(unsigned int cmd, void __user *argp) 523{ 524 struct device_node *dp; 525 phandle nd; 526 527 BUILD_BUG_ON(sizeof(phandle) != sizeof(int)); 528 529 if (copy_from_user(&nd, argp, sizeof(phandle))) 530 return -EFAULT; 531 532 if (nd == 0) { 533 if (cmd != OPIOCGETNEXT) 534 return -EINVAL; 535 dp = of_find_node_by_path("/"); 536 } else { 537 dp = of_find_node_by_phandle(nd); 538 nd = 0; 539 if (dp) { 540 if (cmd == OPIOCGETNEXT) 541 dp = dp->sibling; 542 else 543 dp = dp->child; 544 } 545 } 546 if (dp) 547 nd = dp->phandle; 548 if (copy_to_user(argp, &nd, sizeof(phandle))) 549 return -EFAULT; 550 551 return 0; 552} 553 554static int openprom_bsd_ioctl(struct file * file, 555 unsigned int cmd, unsigned long arg) 556{ 557 DATA *data = (DATA *) file->private_data; 558 void __user *argp = (void __user *)arg; 559 int err; 560 561 lock_kernel(); 562 switch (cmd) { 563 case OPIOCGET: 564 err = opiocget(argp, data); 565 break; 566 567 case OPIOCNEXTPROP: 568 err = opiocnextprop(argp, data); 569 break; 570 571 case OPIOCSET: 572 err = opiocset(argp, data); 573 break; 574 575 case OPIOCGETOPTNODE: 576 BUILD_BUG_ON(sizeof(phandle) != sizeof(int)); 577 578 err = 0; 579 if (copy_to_user(argp, &options_node->phandle, sizeof(phandle))) 580 err = -EFAULT; 581 break; 582 583 case OPIOCGETNEXT: 584 case OPIOCGETCHILD: 585 err = opiocgetnext(cmd, argp); 586 break; 587 588 default: 589 err = -EINVAL; 590 break; 591 }; 592 unlock_kernel(); 593 594 return err; 595} 596 597 598/* 599 * Handoff control to the correct ioctl handler. 600 */ 601static long openprom_ioctl(struct file * file, 602 unsigned int cmd, unsigned long arg) 603{ 604 DATA *data = (DATA *) file->private_data; 605 606 switch (cmd) { 607 case OPROMGETOPT: 608 case OPROMNXTOPT: 609 if ((file->f_mode & FMODE_READ) == 0) 610 return -EPERM; 611 return openprom_sunos_ioctl(file, cmd, arg, 612 options_node); 613 614 case OPROMSETOPT: 615 case OPROMSETOPT2: 616 if ((file->f_mode & FMODE_WRITE) == 0) 617 return -EPERM; 618 return openprom_sunos_ioctl(file, cmd, arg, 619 options_node); 620 621 case OPROMNEXT: 622 case OPROMCHILD: 623 case OPROMGETPROP: 624 case OPROMNXTPROP: 625 if ((file->f_mode & FMODE_READ) == 0) 626 return -EPERM; 627 return openprom_sunos_ioctl(file, cmd, arg, 628 data->current_node); 629 630 case OPROMU2P: 631 case OPROMGETCONS: 632 case OPROMGETFBNAME: 633 case OPROMGETBOOTARGS: 634 case OPROMSETCUR: 635 case OPROMPCI2NODE: 636 case OPROMPATH2NODE: 637 if ((file->f_mode & FMODE_READ) == 0) 638 return -EPERM; 639 return openprom_sunos_ioctl(file, cmd, arg, NULL); 640 641 case OPIOCGET: 642 case OPIOCNEXTPROP: 643 case OPIOCGETOPTNODE: 644 case OPIOCGETNEXT: 645 case OPIOCGETCHILD: 646 if ((file->f_mode & FMODE_READ) == 0) 647 return -EBADF; 648 return openprom_bsd_ioctl(file,cmd,arg); 649 650 case OPIOCSET: 651 if ((file->f_mode & FMODE_WRITE) == 0) 652 return -EBADF; 653 return openprom_bsd_ioctl(file,cmd,arg); 654 655 default: 656 return -EINVAL; 657 }; 658} 659 660static long openprom_compat_ioctl(struct file *file, unsigned int cmd, 661 unsigned long arg) 662{ 663 long rval = -ENOTTY; 664 665 /* 666 * SunOS/Solaris only, the NetBSD one's have embedded pointers in 667 * the arg which we'd need to clean up... 668 */ 669 switch (cmd) { 670 case OPROMGETOPT: 671 case OPROMSETOPT: 672 case OPROMNXTOPT: 673 case OPROMSETOPT2: 674 case OPROMNEXT: 675 case OPROMCHILD: 676 case OPROMGETPROP: 677 case OPROMNXTPROP: 678 case OPROMU2P: 679 case OPROMGETCONS: 680 case OPROMGETFBNAME: 681 case OPROMGETBOOTARGS: 682 case OPROMSETCUR: 683 case OPROMPCI2NODE: 684 case OPROMPATH2NODE: 685 rval = openprom_ioctl(file, cmd, arg); 686 break; 687 } 688 689 return rval; 690} 691 692static int openprom_open(struct inode * inode, struct file * file) 693{ 694 DATA *data; 695 696 data = kmalloc(sizeof(DATA), GFP_KERNEL); 697 if (!data) 698 return -ENOMEM; 699 700 lock_kernel(); 701 data->current_node = of_find_node_by_path("/"); 702 data->lastnode = data->current_node; 703 file->private_data = (void *) data; 704 unlock_kernel(); 705 706 return 0; 707} 708 709static int openprom_release(struct inode * inode, struct file * file) 710{ 711 kfree(file->private_data); 712 return 0; 713} 714 715static const struct file_operations openprom_fops = { 716 .owner = THIS_MODULE, 717 .llseek = no_llseek, 718 .unlocked_ioctl = openprom_ioctl, 719 .compat_ioctl = openprom_compat_ioctl, 720 .open = openprom_open, 721 .release = openprom_release, 722}; 723 724static struct miscdevice openprom_dev = { 725 .minor = SUN_OPENPROM_MINOR, 726 .name = "openprom", 727 .fops = &openprom_fops, 728}; 729 730static int __init openprom_init(void) 731{ 732 struct device_node *dp; 733 int err; 734 735 err = misc_register(&openprom_dev); 736 if (err) 737 return err; 738 739 dp = of_find_node_by_path("/"); 740 dp = dp->child; 741 while (dp) { 742 if (!strcmp(dp->name, "options")) 743 break; 744 dp = dp->sibling; 745 } 746 options_node = dp; 747 748 if (!options_node) { 749 misc_deregister(&openprom_dev); 750 return -EIO; 751 } 752 753 return 0; 754} 755 756static void __exit openprom_cleanup(void) 757{ 758 misc_deregister(&openprom_dev); 759} 760 761module_init(openprom_init); 762module_exit(openprom_cleanup); 763