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/uaccess.h> 44 #include <asm/openpromio.h> 45 #ifdef CONFIG_PCI 46 #include <linux/pci.h> 47 #endif 48 49 MODULE_AUTHOR("Thomas K. Dyas (tdyas@noc.rutgers.edu) and Eddie C. Dost (ecd@skynet.be)"); 50 MODULE_DESCRIPTION("OPENPROM Configuration Driver"); 51 MODULE_LICENSE("GPL"); 52 MODULE_VERSION("1.0"); 53 MODULE_ALIAS_MISCDEV(SUN_OPENPROM_MINOR); 54 55 /* Private data kept by the driver for each descriptor. */ 56 typedef struct openprom_private_data 57 { 58 struct device_node *current_node; /* Current node for SunOS ioctls. */ 59 struct device_node *lastnode; /* Last valid node used by BSD ioctls. */ 60 } DATA; 61 62 /* ID of the PROM node containing all of the EEPROM options. */ 63 static DEFINE_MUTEX(openprom_mutex); 64 static 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 */ 73 static 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 } 102 103 static 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 */ 136 static 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 } 142 143 static 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 } 159 160 static 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 } 189 190 static 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 } 197 198 static 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 } 244 245 static 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 } 269 270 static 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 } 283 284 static 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 */ 301 static 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 mutex_lock(&openprom_mutex); 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 mutex_unlock(&openprom_mutex); 371 372 return error; 373 } 374 375 static 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. */ 386 static 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 = memdup_user_nul(user, len); 394 if (IS_ERR(tmp)) 395 return PTR_ERR(tmp); 396 397 *ptr = tmp; 398 399 return 0; 400 } 401 402 /* 403 * NetBSD /dev/openprom ioctl calls. 404 */ 405 static int opiocget(void __user *argp, DATA *data) 406 { 407 struct opiocdesc op; 408 struct device_node *dp; 409 char *str; 410 const void *pval; 411 int err, len; 412 413 if (copy_from_user(&op, argp, sizeof(op))) 414 return -EFAULT; 415 416 dp = get_node(op.op_nodeid, data); 417 418 err = copyin_string(op.op_name, op.op_namelen, &str); 419 if (err) 420 return err; 421 422 pval = of_get_property(dp, str, &len); 423 err = 0; 424 if (!pval || len > op.op_buflen) { 425 err = -EINVAL; 426 } else { 427 op.op_buflen = len; 428 if (copy_to_user(argp, &op, sizeof(op)) || 429 copy_to_user(op.op_buf, pval, len)) 430 err = -EFAULT; 431 } 432 kfree(str); 433 434 return err; 435 } 436 437 static int opiocnextprop(void __user *argp, DATA *data) 438 { 439 struct opiocdesc op; 440 struct device_node *dp; 441 struct property *prop; 442 char *str; 443 int err, len; 444 445 if (copy_from_user(&op, argp, sizeof(op))) 446 return -EFAULT; 447 448 dp = get_node(op.op_nodeid, data); 449 if (!dp) 450 return -EINVAL; 451 452 err = copyin_string(op.op_name, op.op_namelen, &str); 453 if (err) 454 return err; 455 456 if (str[0] == '\0') { 457 prop = dp->properties; 458 } else { 459 prop = of_find_property(dp, str, NULL); 460 if (prop) 461 prop = prop->next; 462 } 463 kfree(str); 464 465 if (!prop) 466 len = 0; 467 else 468 len = prop->length; 469 470 if (len > op.op_buflen) 471 len = op.op_buflen; 472 473 if (copy_to_user(argp, &op, sizeof(op))) 474 return -EFAULT; 475 476 if (len && 477 copy_to_user(op.op_buf, prop->value, len)) 478 return -EFAULT; 479 480 return 0; 481 } 482 483 static int opiocset(void __user *argp, DATA *data) 484 { 485 struct opiocdesc op; 486 struct device_node *dp; 487 char *str, *tmp; 488 int err; 489 490 if (copy_from_user(&op, argp, sizeof(op))) 491 return -EFAULT; 492 493 dp = get_node(op.op_nodeid, data); 494 if (!dp) 495 return -EINVAL; 496 497 err = copyin_string(op.op_name, op.op_namelen, &str); 498 if (err) 499 return err; 500 501 err = copyin_string(op.op_buf, op.op_buflen, &tmp); 502 if (err) { 503 kfree(str); 504 return err; 505 } 506 507 err = of_set_property(dp, str, tmp, op.op_buflen); 508 509 kfree(str); 510 kfree(tmp); 511 512 return err; 513 } 514 515 static int opiocgetnext(unsigned int cmd, void __user *argp) 516 { 517 struct device_node *dp; 518 phandle nd; 519 520 BUILD_BUG_ON(sizeof(phandle) != sizeof(int)); 521 522 if (copy_from_user(&nd, argp, sizeof(phandle))) 523 return -EFAULT; 524 525 if (nd == 0) { 526 if (cmd != OPIOCGETNEXT) 527 return -EINVAL; 528 dp = of_find_node_by_path("/"); 529 } else { 530 dp = of_find_node_by_phandle(nd); 531 nd = 0; 532 if (dp) { 533 if (cmd == OPIOCGETNEXT) 534 dp = dp->sibling; 535 else 536 dp = dp->child; 537 } 538 } 539 if (dp) 540 nd = dp->phandle; 541 if (copy_to_user(argp, &nd, sizeof(phandle))) 542 return -EFAULT; 543 544 return 0; 545 } 546 547 static int openprom_bsd_ioctl(struct file * file, 548 unsigned int cmd, unsigned long arg) 549 { 550 DATA *data = file->private_data; 551 void __user *argp = (void __user *)arg; 552 int err; 553 554 mutex_lock(&openprom_mutex); 555 switch (cmd) { 556 case OPIOCGET: 557 err = opiocget(argp, data); 558 break; 559 560 case OPIOCNEXTPROP: 561 err = opiocnextprop(argp, data); 562 break; 563 564 case OPIOCSET: 565 err = opiocset(argp, data); 566 break; 567 568 case OPIOCGETOPTNODE: 569 BUILD_BUG_ON(sizeof(phandle) != sizeof(int)); 570 571 err = 0; 572 if (copy_to_user(argp, &options_node->phandle, sizeof(phandle))) 573 err = -EFAULT; 574 break; 575 576 case OPIOCGETNEXT: 577 case OPIOCGETCHILD: 578 err = opiocgetnext(cmd, argp); 579 break; 580 581 default: 582 err = -EINVAL; 583 break; 584 } 585 mutex_unlock(&openprom_mutex); 586 587 return err; 588 } 589 590 591 /* 592 * Handoff control to the correct ioctl handler. 593 */ 594 static long openprom_ioctl(struct file * file, 595 unsigned int cmd, unsigned long arg) 596 { 597 DATA *data = file->private_data; 598 599 switch (cmd) { 600 case OPROMGETOPT: 601 case OPROMNXTOPT: 602 if ((file->f_mode & FMODE_READ) == 0) 603 return -EPERM; 604 return openprom_sunos_ioctl(file, cmd, arg, 605 options_node); 606 607 case OPROMSETOPT: 608 case OPROMSETOPT2: 609 if ((file->f_mode & FMODE_WRITE) == 0) 610 return -EPERM; 611 return openprom_sunos_ioctl(file, cmd, arg, 612 options_node); 613 614 case OPROMNEXT: 615 case OPROMCHILD: 616 case OPROMGETPROP: 617 case OPROMNXTPROP: 618 if ((file->f_mode & FMODE_READ) == 0) 619 return -EPERM; 620 return openprom_sunos_ioctl(file, cmd, arg, 621 data->current_node); 622 623 case OPROMU2P: 624 case OPROMGETCONS: 625 case OPROMGETFBNAME: 626 case OPROMGETBOOTARGS: 627 case OPROMSETCUR: 628 case OPROMPCI2NODE: 629 case OPROMPATH2NODE: 630 if ((file->f_mode & FMODE_READ) == 0) 631 return -EPERM; 632 return openprom_sunos_ioctl(file, cmd, arg, NULL); 633 634 case OPIOCGET: 635 case OPIOCNEXTPROP: 636 case OPIOCGETOPTNODE: 637 case OPIOCGETNEXT: 638 case OPIOCGETCHILD: 639 if ((file->f_mode & FMODE_READ) == 0) 640 return -EBADF; 641 return openprom_bsd_ioctl(file,cmd,arg); 642 643 case OPIOCSET: 644 if ((file->f_mode & FMODE_WRITE) == 0) 645 return -EBADF; 646 return openprom_bsd_ioctl(file,cmd,arg); 647 648 default: 649 return -EINVAL; 650 }; 651 } 652 653 static long openprom_compat_ioctl(struct file *file, unsigned int cmd, 654 unsigned long arg) 655 { 656 long rval = -ENOTTY; 657 658 /* 659 * SunOS/Solaris only, the NetBSD one's have embedded pointers in 660 * the arg which we'd need to clean up... 661 */ 662 switch (cmd) { 663 case OPROMGETOPT: 664 case OPROMSETOPT: 665 case OPROMNXTOPT: 666 case OPROMSETOPT2: 667 case OPROMNEXT: 668 case OPROMCHILD: 669 case OPROMGETPROP: 670 case OPROMNXTPROP: 671 case OPROMU2P: 672 case OPROMGETCONS: 673 case OPROMGETFBNAME: 674 case OPROMGETBOOTARGS: 675 case OPROMSETCUR: 676 case OPROMPCI2NODE: 677 case OPROMPATH2NODE: 678 rval = openprom_ioctl(file, cmd, arg); 679 break; 680 } 681 682 return rval; 683 } 684 685 static int openprom_open(struct inode * inode, struct file * file) 686 { 687 DATA *data; 688 689 data = kmalloc(sizeof(DATA), GFP_KERNEL); 690 if (!data) 691 return -ENOMEM; 692 693 mutex_lock(&openprom_mutex); 694 data->current_node = of_find_node_by_path("/"); 695 data->lastnode = data->current_node; 696 file->private_data = (void *) data; 697 mutex_unlock(&openprom_mutex); 698 699 return 0; 700 } 701 702 static int openprom_release(struct inode * inode, struct file * file) 703 { 704 kfree(file->private_data); 705 return 0; 706 } 707 708 static const struct file_operations openprom_fops = { 709 .owner = THIS_MODULE, 710 .llseek = no_llseek, 711 .unlocked_ioctl = openprom_ioctl, 712 .compat_ioctl = openprom_compat_ioctl, 713 .open = openprom_open, 714 .release = openprom_release, 715 }; 716 717 static struct miscdevice openprom_dev = { 718 .minor = SUN_OPENPROM_MINOR, 719 .name = "openprom", 720 .fops = &openprom_fops, 721 }; 722 723 static int __init openprom_init(void) 724 { 725 struct device_node *dp; 726 int err; 727 728 err = misc_register(&openprom_dev); 729 if (err) 730 return err; 731 732 dp = of_find_node_by_path("/"); 733 dp = dp->child; 734 while (dp) { 735 if (!strcmp(dp->name, "options")) 736 break; 737 dp = dp->sibling; 738 } 739 options_node = dp; 740 741 if (!options_node) { 742 misc_deregister(&openprom_dev); 743 return -EIO; 744 } 745 746 return 0; 747 } 748 749 static void __exit openprom_cleanup(void) 750 { 751 misc_deregister(&openprom_dev); 752 } 753 754 module_init(openprom_init); 755 module_exit(openprom_cleanup); 756