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/mutex.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 50 MODULE_AUTHOR("Thomas K. Dyas (tdyas@noc.rutgers.edu) and Eddie C. Dost (ecd@skynet.be)"); 51 MODULE_DESCRIPTION("OPENPROM Configuration Driver"); 52 MODULE_LICENSE("GPL"); 53 MODULE_VERSION("1.0"); 54 MODULE_ALIAS_MISCDEV(SUN_OPENPROM_MINOR); 55 56 /* Private data kept by the driver for each descriptor. */ 57 typedef 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. */ 64 static DEFINE_MUTEX(openprom_mutex); 65 static struct device_node *options_node; 66 67 /* 68 * Copy an openpromio structure into kernel space from user space. 69 * This routine does error checking to make sure that all memory 70 * accesses are within bounds. A pointer to the allocated openpromio 71 * structure will be placed in "*opp_p". Return value is the length 72 * of the user supplied buffer. 73 */ 74 static int copyin(struct openpromio __user *info, struct openpromio **opp_p) 75 { 76 unsigned int bufsize; 77 78 if (!info || !opp_p) 79 return -EFAULT; 80 81 if (get_user(bufsize, &info->oprom_size)) 82 return -EFAULT; 83 84 if (bufsize == 0) 85 return -EINVAL; 86 87 /* If the bufsize is too large, just limit it. 88 * Fix from Jason Rappleye. 89 */ 90 if (bufsize > OPROMMAXPARAM) 91 bufsize = OPROMMAXPARAM; 92 93 if (!(*opp_p = kzalloc(sizeof(int) + bufsize + 1, GFP_KERNEL))) 94 return -ENOMEM; 95 96 if (copy_from_user(&(*opp_p)->oprom_array, 97 &info->oprom_array, bufsize)) { 98 kfree(*opp_p); 99 return -EFAULT; 100 } 101 return bufsize; 102 } 103 104 static int getstrings(struct openpromio __user *info, struct openpromio **opp_p) 105 { 106 int n, bufsize; 107 char c; 108 109 if (!info || !opp_p) 110 return -EFAULT; 111 112 if (!(*opp_p = kzalloc(sizeof(int) + OPROMMAXPARAM + 1, GFP_KERNEL))) 113 return -ENOMEM; 114 115 (*opp_p)->oprom_size = 0; 116 117 n = bufsize = 0; 118 while ((n < 2) && (bufsize < OPROMMAXPARAM)) { 119 if (get_user(c, &info->oprom_array[bufsize])) { 120 kfree(*opp_p); 121 return -EFAULT; 122 } 123 if (c == '\0') 124 n++; 125 (*opp_p)->oprom_array[bufsize++] = c; 126 } 127 if (!n) { 128 kfree(*opp_p); 129 return -EINVAL; 130 } 131 return bufsize; 132 } 133 134 /* 135 * Copy an openpromio structure in kernel space back to user space. 136 */ 137 static int copyout(void __user *info, struct openpromio *opp, int len) 138 { 139 if (copy_to_user(info, opp, len)) 140 return -EFAULT; 141 return 0; 142 } 143 144 static int opromgetprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize) 145 { 146 const void *pval; 147 int len; 148 149 if (!dp || 150 !(pval = of_get_property(dp, op->oprom_array, &len)) || 151 len <= 0 || len > bufsize) 152 return copyout(argp, op, sizeof(int)); 153 154 memcpy(op->oprom_array, pval, len); 155 op->oprom_array[len] = '\0'; 156 op->oprom_size = len; 157 158 return copyout(argp, op, sizeof(int) + bufsize); 159 } 160 161 static int opromnxtprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize) 162 { 163 struct property *prop; 164 int len; 165 166 if (!dp) 167 return copyout(argp, op, sizeof(int)); 168 if (op->oprom_array[0] == '\0') { 169 prop = dp->properties; 170 if (!prop) 171 return copyout(argp, op, sizeof(int)); 172 len = strlen(prop->name); 173 } else { 174 prop = of_find_property(dp, op->oprom_array, NULL); 175 176 if (!prop || 177 !prop->next || 178 (len = strlen(prop->next->name)) + 1 > bufsize) 179 return copyout(argp, op, sizeof(int)); 180 181 prop = prop->next; 182 } 183 184 memcpy(op->oprom_array, prop->name, len); 185 op->oprom_array[len] = '\0'; 186 op->oprom_size = ++len; 187 188 return copyout(argp, op, sizeof(int) + bufsize); 189 } 190 191 static int opromsetopt(struct device_node *dp, struct openpromio *op, int bufsize) 192 { 193 char *buf = op->oprom_array + strlen(op->oprom_array) + 1; 194 int len = op->oprom_array + bufsize - buf; 195 196 return of_set_property(options_node, op->oprom_array, buf, len); 197 } 198 199 static int opromnext(void __user *argp, unsigned int cmd, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data) 200 { 201 phandle ph; 202 203 BUILD_BUG_ON(sizeof(phandle) != sizeof(int)); 204 205 if (bufsize < sizeof(phandle)) 206 return -EINVAL; 207 208 ph = *((int *) op->oprom_array); 209 if (ph) { 210 dp = of_find_node_by_phandle(ph); 211 if (!dp) 212 return -EINVAL; 213 214 switch (cmd) { 215 case OPROMNEXT: 216 dp = dp->sibling; 217 break; 218 219 case OPROMCHILD: 220 dp = dp->child; 221 break; 222 223 case OPROMSETCUR: 224 default: 225 break; 226 }; 227 } else { 228 /* Sibling of node zero is the root node. */ 229 if (cmd != OPROMNEXT) 230 return -EINVAL; 231 232 dp = of_find_node_by_path("/"); 233 } 234 235 ph = 0; 236 if (dp) 237 ph = dp->phandle; 238 239 data->current_node = dp; 240 *((int *) op->oprom_array) = ph; 241 op->oprom_size = sizeof(phandle); 242 243 return copyout(argp, op, bufsize + sizeof(int)); 244 } 245 246 static int oprompci2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data) 247 { 248 int err = -EINVAL; 249 250 if (bufsize >= 2*sizeof(int)) { 251 #ifdef CONFIG_PCI 252 struct pci_dev *pdev; 253 struct device_node *dp; 254 255 pdev = pci_get_bus_and_slot (((int *) op->oprom_array)[0], 256 ((int *) op->oprom_array)[1]); 257 258 dp = pci_device_to_OF_node(pdev); 259 data->current_node = dp; 260 *((int *)op->oprom_array) = dp->phandle; 261 op->oprom_size = sizeof(int); 262 err = copyout(argp, op, bufsize + sizeof(int)); 263 264 pci_dev_put(pdev); 265 #endif 266 } 267 268 return err; 269 } 270 271 static int oprompath2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data) 272 { 273 phandle ph = 0; 274 275 dp = of_find_node_by_path(op->oprom_array); 276 if (dp) 277 ph = dp->phandle; 278 data->current_node = dp; 279 *((int *)op->oprom_array) = ph; 280 op->oprom_size = sizeof(int); 281 282 return copyout(argp, op, bufsize + sizeof(int)); 283 } 284 285 static int opromgetbootargs(void __user *argp, struct openpromio *op, int bufsize) 286 { 287 char *buf = saved_command_line; 288 int len = strlen(buf); 289 290 if (len > bufsize) 291 return -EINVAL; 292 293 strcpy(op->oprom_array, buf); 294 op->oprom_size = len; 295 296 return copyout(argp, op, bufsize + sizeof(int)); 297 } 298 299 /* 300 * SunOS and Solaris /dev/openprom ioctl calls. 301 */ 302 static long openprom_sunos_ioctl(struct file * file, 303 unsigned int cmd, unsigned long arg, 304 struct device_node *dp) 305 { 306 DATA *data = file->private_data; 307 struct openpromio *opp = NULL; 308 int bufsize, error = 0; 309 static int cnt; 310 void __user *argp = (void __user *)arg; 311 312 if (cmd == OPROMSETOPT) 313 bufsize = getstrings(argp, &opp); 314 else 315 bufsize = copyin(argp, &opp); 316 317 if (bufsize < 0) 318 return bufsize; 319 320 mutex_lock(&openprom_mutex); 321 322 switch (cmd) { 323 case OPROMGETOPT: 324 case OPROMGETPROP: 325 error = opromgetprop(argp, dp, opp, bufsize); 326 break; 327 328 case OPROMNXTOPT: 329 case OPROMNXTPROP: 330 error = opromnxtprop(argp, dp, opp, bufsize); 331 break; 332 333 case OPROMSETOPT: 334 case OPROMSETOPT2: 335 error = opromsetopt(dp, opp, bufsize); 336 break; 337 338 case OPROMNEXT: 339 case OPROMCHILD: 340 case OPROMSETCUR: 341 error = opromnext(argp, cmd, dp, opp, bufsize, data); 342 break; 343 344 case OPROMPCI2NODE: 345 error = oprompci2node(argp, dp, opp, bufsize, data); 346 break; 347 348 case OPROMPATH2NODE: 349 error = oprompath2node(argp, dp, opp, bufsize, data); 350 break; 351 352 case OPROMGETBOOTARGS: 353 error = opromgetbootargs(argp, opp, bufsize); 354 break; 355 356 case OPROMU2P: 357 case OPROMGETCONS: 358 case OPROMGETFBNAME: 359 if (cnt++ < 10) 360 printk(KERN_INFO "openprom_sunos_ioctl: unimplemented ioctl\n"); 361 error = -EINVAL; 362 break; 363 default: 364 if (cnt++ < 10) 365 printk(KERN_INFO "openprom_sunos_ioctl: cmd 0x%X, arg 0x%lX\n", cmd, arg); 366 error = -EINVAL; 367 break; 368 } 369 370 kfree(opp); 371 mutex_unlock(&openprom_mutex); 372 373 return error; 374 } 375 376 static struct device_node *get_node(phandle n, DATA *data) 377 { 378 struct device_node *dp = of_find_node_by_phandle(n); 379 380 if (dp) 381 data->lastnode = dp; 382 383 return dp; 384 } 385 386 /* Copy in a whole string from userspace into kernelspace. */ 387 static int copyin_string(char __user *user, size_t len, char **ptr) 388 { 389 char *tmp; 390 391 if ((ssize_t)len < 0 || (ssize_t)(len + 1) < 0) 392 return -EINVAL; 393 394 tmp = kmalloc(len + 1, GFP_KERNEL); 395 if (!tmp) 396 return -ENOMEM; 397 398 if (copy_from_user(tmp, user, len)) { 399 kfree(tmp); 400 return -EFAULT; 401 } 402 403 tmp[len] = '\0'; 404 405 *ptr = tmp; 406 407 return 0; 408 } 409 410 /* 411 * NetBSD /dev/openprom ioctl calls. 412 */ 413 static int opiocget(void __user *argp, DATA *data) 414 { 415 struct opiocdesc op; 416 struct device_node *dp; 417 char *str; 418 const void *pval; 419 int err, len; 420 421 if (copy_from_user(&op, argp, sizeof(op))) 422 return -EFAULT; 423 424 dp = get_node(op.op_nodeid, data); 425 426 err = copyin_string(op.op_name, op.op_namelen, &str); 427 if (err) 428 return err; 429 430 pval = of_get_property(dp, str, &len); 431 err = 0; 432 if (!pval || len > op.op_buflen) { 433 err = -EINVAL; 434 } else { 435 op.op_buflen = len; 436 if (copy_to_user(argp, &op, sizeof(op)) || 437 copy_to_user(op.op_buf, pval, len)) 438 err = -EFAULT; 439 } 440 kfree(str); 441 442 return err; 443 } 444 445 static int opiocnextprop(void __user *argp, DATA *data) 446 { 447 struct opiocdesc op; 448 struct device_node *dp; 449 struct property *prop; 450 char *str; 451 int err, len; 452 453 if (copy_from_user(&op, argp, sizeof(op))) 454 return -EFAULT; 455 456 dp = get_node(op.op_nodeid, data); 457 if (!dp) 458 return -EINVAL; 459 460 err = copyin_string(op.op_name, op.op_namelen, &str); 461 if (err) 462 return err; 463 464 if (str[0] == '\0') { 465 prop = dp->properties; 466 } else { 467 prop = of_find_property(dp, str, NULL); 468 if (prop) 469 prop = prop->next; 470 } 471 kfree(str); 472 473 if (!prop) 474 len = 0; 475 else 476 len = prop->length; 477 478 if (len > op.op_buflen) 479 len = op.op_buflen; 480 481 if (copy_to_user(argp, &op, sizeof(op))) 482 return -EFAULT; 483 484 if (len && 485 copy_to_user(op.op_buf, prop->value, len)) 486 return -EFAULT; 487 488 return 0; 489 } 490 491 static int opiocset(void __user *argp, DATA *data) 492 { 493 struct opiocdesc op; 494 struct device_node *dp; 495 char *str, *tmp; 496 int err; 497 498 if (copy_from_user(&op, argp, sizeof(op))) 499 return -EFAULT; 500 501 dp = get_node(op.op_nodeid, data); 502 if (!dp) 503 return -EINVAL; 504 505 err = copyin_string(op.op_name, op.op_namelen, &str); 506 if (err) 507 return err; 508 509 err = copyin_string(op.op_buf, op.op_buflen, &tmp); 510 if (err) { 511 kfree(str); 512 return err; 513 } 514 515 err = of_set_property(dp, str, tmp, op.op_buflen); 516 517 kfree(str); 518 kfree(tmp); 519 520 return err; 521 } 522 523 static int opiocgetnext(unsigned int cmd, void __user *argp) 524 { 525 struct device_node *dp; 526 phandle nd; 527 528 BUILD_BUG_ON(sizeof(phandle) != sizeof(int)); 529 530 if (copy_from_user(&nd, argp, sizeof(phandle))) 531 return -EFAULT; 532 533 if (nd == 0) { 534 if (cmd != OPIOCGETNEXT) 535 return -EINVAL; 536 dp = of_find_node_by_path("/"); 537 } else { 538 dp = of_find_node_by_phandle(nd); 539 nd = 0; 540 if (dp) { 541 if (cmd == OPIOCGETNEXT) 542 dp = dp->sibling; 543 else 544 dp = dp->child; 545 } 546 } 547 if (dp) 548 nd = dp->phandle; 549 if (copy_to_user(argp, &nd, sizeof(phandle))) 550 return -EFAULT; 551 552 return 0; 553 } 554 555 static int openprom_bsd_ioctl(struct file * file, 556 unsigned int cmd, unsigned long arg) 557 { 558 DATA *data = file->private_data; 559 void __user *argp = (void __user *)arg; 560 int err; 561 562 mutex_lock(&openprom_mutex); 563 switch (cmd) { 564 case OPIOCGET: 565 err = opiocget(argp, data); 566 break; 567 568 case OPIOCNEXTPROP: 569 err = opiocnextprop(argp, data); 570 break; 571 572 case OPIOCSET: 573 err = opiocset(argp, data); 574 break; 575 576 case OPIOCGETOPTNODE: 577 BUILD_BUG_ON(sizeof(phandle) != sizeof(int)); 578 579 err = 0; 580 if (copy_to_user(argp, &options_node->phandle, sizeof(phandle))) 581 err = -EFAULT; 582 break; 583 584 case OPIOCGETNEXT: 585 case OPIOCGETCHILD: 586 err = opiocgetnext(cmd, argp); 587 break; 588 589 default: 590 err = -EINVAL; 591 break; 592 }; 593 mutex_unlock(&openprom_mutex); 594 595 return err; 596 } 597 598 599 /* 600 * Handoff control to the correct ioctl handler. 601 */ 602 static long openprom_ioctl(struct file * file, 603 unsigned int cmd, unsigned long arg) 604 { 605 DATA *data = file->private_data; 606 607 switch (cmd) { 608 case OPROMGETOPT: 609 case OPROMNXTOPT: 610 if ((file->f_mode & FMODE_READ) == 0) 611 return -EPERM; 612 return openprom_sunos_ioctl(file, cmd, arg, 613 options_node); 614 615 case OPROMSETOPT: 616 case OPROMSETOPT2: 617 if ((file->f_mode & FMODE_WRITE) == 0) 618 return -EPERM; 619 return openprom_sunos_ioctl(file, cmd, arg, 620 options_node); 621 622 case OPROMNEXT: 623 case OPROMCHILD: 624 case OPROMGETPROP: 625 case OPROMNXTPROP: 626 if ((file->f_mode & FMODE_READ) == 0) 627 return -EPERM; 628 return openprom_sunos_ioctl(file, cmd, arg, 629 data->current_node); 630 631 case OPROMU2P: 632 case OPROMGETCONS: 633 case OPROMGETFBNAME: 634 case OPROMGETBOOTARGS: 635 case OPROMSETCUR: 636 case OPROMPCI2NODE: 637 case OPROMPATH2NODE: 638 if ((file->f_mode & FMODE_READ) == 0) 639 return -EPERM; 640 return openprom_sunos_ioctl(file, cmd, arg, NULL); 641 642 case OPIOCGET: 643 case OPIOCNEXTPROP: 644 case OPIOCGETOPTNODE: 645 case OPIOCGETNEXT: 646 case OPIOCGETCHILD: 647 if ((file->f_mode & FMODE_READ) == 0) 648 return -EBADF; 649 return openprom_bsd_ioctl(file,cmd,arg); 650 651 case OPIOCSET: 652 if ((file->f_mode & FMODE_WRITE) == 0) 653 return -EBADF; 654 return openprom_bsd_ioctl(file,cmd,arg); 655 656 default: 657 return -EINVAL; 658 }; 659 } 660 661 static long openprom_compat_ioctl(struct file *file, unsigned int cmd, 662 unsigned long arg) 663 { 664 long rval = -ENOTTY; 665 666 /* 667 * SunOS/Solaris only, the NetBSD one's have embedded pointers in 668 * the arg which we'd need to clean up... 669 */ 670 switch (cmd) { 671 case OPROMGETOPT: 672 case OPROMSETOPT: 673 case OPROMNXTOPT: 674 case OPROMSETOPT2: 675 case OPROMNEXT: 676 case OPROMCHILD: 677 case OPROMGETPROP: 678 case OPROMNXTPROP: 679 case OPROMU2P: 680 case OPROMGETCONS: 681 case OPROMGETFBNAME: 682 case OPROMGETBOOTARGS: 683 case OPROMSETCUR: 684 case OPROMPCI2NODE: 685 case OPROMPATH2NODE: 686 rval = openprom_ioctl(file, cmd, arg); 687 break; 688 } 689 690 return rval; 691 } 692 693 static int openprom_open(struct inode * inode, struct file * file) 694 { 695 DATA *data; 696 697 data = kmalloc(sizeof(DATA), GFP_KERNEL); 698 if (!data) 699 return -ENOMEM; 700 701 mutex_lock(&openprom_mutex); 702 data->current_node = of_find_node_by_path("/"); 703 data->lastnode = data->current_node; 704 file->private_data = (void *) data; 705 mutex_unlock(&openprom_mutex); 706 707 return 0; 708 } 709 710 static int openprom_release(struct inode * inode, struct file * file) 711 { 712 kfree(file->private_data); 713 return 0; 714 } 715 716 static const struct file_operations openprom_fops = { 717 .owner = THIS_MODULE, 718 .llseek = no_llseek, 719 .unlocked_ioctl = openprom_ioctl, 720 .compat_ioctl = openprom_compat_ioctl, 721 .open = openprom_open, 722 .release = openprom_release, 723 }; 724 725 static struct miscdevice openprom_dev = { 726 .minor = SUN_OPENPROM_MINOR, 727 .name = "openprom", 728 .fops = &openprom_fops, 729 }; 730 731 static int __init openprom_init(void) 732 { 733 struct device_node *dp; 734 int err; 735 736 err = misc_register(&openprom_dev); 737 if (err) 738 return err; 739 740 dp = of_find_node_by_path("/"); 741 dp = dp->child; 742 while (dp) { 743 if (!strcmp(dp->name, "options")) 744 break; 745 dp = dp->sibling; 746 } 747 options_node = dp; 748 749 if (!options_node) { 750 misc_deregister(&openprom_dev); 751 return -EIO; 752 } 753 754 return 0; 755 } 756 757 static void __exit openprom_cleanup(void) 758 { 759 misc_deregister(&openprom_dev); 760 } 761 762 module_init(openprom_init); 763 module_exit(openprom_cleanup); 764