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 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 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 int openprom_sunos_ioctl(struct inode * inode, 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 switch (cmd) { 320 case OPROMGETOPT: 321 case OPROMGETPROP: 322 error = opromgetprop(argp, dp, opp, bufsize); 323 break; 324 325 case OPROMNXTOPT: 326 case OPROMNXTPROP: 327 error = opromnxtprop(argp, dp, opp, bufsize); 328 break; 329 330 case OPROMSETOPT: 331 case OPROMSETOPT2: 332 error = opromsetopt(dp, opp, bufsize); 333 break; 334 335 case OPROMNEXT: 336 case OPROMCHILD: 337 case OPROMSETCUR: 338 error = opromnext(argp, cmd, dp, opp, bufsize, data); 339 break; 340 341 case OPROMPCI2NODE: 342 error = oprompci2node(argp, dp, opp, bufsize, data); 343 break; 344 345 case OPROMPATH2NODE: 346 error = oprompath2node(argp, dp, opp, bufsize, data); 347 break; 348 349 case OPROMGETBOOTARGS: 350 error = opromgetbootargs(argp, opp, bufsize); 351 break; 352 353 case OPROMU2P: 354 case OPROMGETCONS: 355 case OPROMGETFBNAME: 356 if (cnt++ < 10) 357 printk(KERN_INFO "openprom_sunos_ioctl: unimplemented ioctl\n"); 358 error = -EINVAL; 359 break; 360 default: 361 if (cnt++ < 10) 362 printk(KERN_INFO "openprom_sunos_ioctl: cmd 0x%X, arg 0x%lX\n", cmd, arg); 363 error = -EINVAL; 364 break; 365 } 366 367 kfree(opp); 368 return error; 369 } 370 371 static struct device_node *get_node(phandle n, DATA *data) 372 { 373 struct device_node *dp = of_find_node_by_phandle(n); 374 375 if (dp) 376 data->lastnode = dp; 377 378 return dp; 379 } 380 381 /* Copy in a whole string from userspace into kernelspace. */ 382 static int copyin_string(char __user *user, size_t len, char **ptr) 383 { 384 char *tmp; 385 386 if ((ssize_t)len < 0 || (ssize_t)(len + 1) < 0) 387 return -EINVAL; 388 389 tmp = kmalloc(len + 1, GFP_KERNEL); 390 if (!tmp) 391 return -ENOMEM; 392 393 if (copy_from_user(tmp, user, len)) { 394 kfree(tmp); 395 return -EFAULT; 396 } 397 398 tmp[len] = '\0'; 399 400 *ptr = tmp; 401 402 return 0; 403 } 404 405 /* 406 * NetBSD /dev/openprom ioctl calls. 407 */ 408 static int opiocget(void __user *argp, DATA *data) 409 { 410 struct opiocdesc op; 411 struct device_node *dp; 412 char *str; 413 const void *pval; 414 int err, len; 415 416 if (copy_from_user(&op, argp, sizeof(op))) 417 return -EFAULT; 418 419 dp = get_node(op.op_nodeid, data); 420 421 err = copyin_string(op.op_name, op.op_namelen, &str); 422 if (err) 423 return err; 424 425 pval = of_get_property(dp, str, &len); 426 err = 0; 427 if (!pval || len > op.op_buflen) { 428 err = -EINVAL; 429 } else { 430 op.op_buflen = len; 431 if (copy_to_user(argp, &op, sizeof(op)) || 432 copy_to_user(op.op_buf, pval, len)) 433 err = -EFAULT; 434 } 435 kfree(str); 436 437 return err; 438 } 439 440 static int opiocnextprop(void __user *argp, DATA *data) 441 { 442 struct opiocdesc op; 443 struct device_node *dp; 444 struct property *prop; 445 char *str; 446 int err, len; 447 448 if (copy_from_user(&op, argp, sizeof(op))) 449 return -EFAULT; 450 451 dp = get_node(op.op_nodeid, data); 452 if (!dp) 453 return -EINVAL; 454 455 err = copyin_string(op.op_name, op.op_namelen, &str); 456 if (err) 457 return err; 458 459 if (str[0] == '\0') { 460 prop = dp->properties; 461 } else { 462 prop = of_find_property(dp, str, NULL); 463 if (prop) 464 prop = prop->next; 465 } 466 kfree(str); 467 468 if (!prop) 469 len = 0; 470 else 471 len = prop->length; 472 473 if (len > op.op_buflen) 474 len = op.op_buflen; 475 476 if (copy_to_user(argp, &op, sizeof(op))) 477 return -EFAULT; 478 479 if (len && 480 copy_to_user(op.op_buf, prop->value, len)) 481 return -EFAULT; 482 483 return 0; 484 } 485 486 static int opiocset(void __user *argp, DATA *data) 487 { 488 struct opiocdesc op; 489 struct device_node *dp; 490 char *str, *tmp; 491 int err; 492 493 if (copy_from_user(&op, argp, sizeof(op))) 494 return -EFAULT; 495 496 dp = get_node(op.op_nodeid, data); 497 if (!dp) 498 return -EINVAL; 499 500 err = copyin_string(op.op_name, op.op_namelen, &str); 501 if (err) 502 return err; 503 504 err = copyin_string(op.op_buf, op.op_buflen, &tmp); 505 if (err) { 506 kfree(str); 507 return err; 508 } 509 510 err = of_set_property(dp, str, tmp, op.op_buflen); 511 512 kfree(str); 513 kfree(tmp); 514 515 return err; 516 } 517 518 static int opiocgetnext(unsigned int cmd, void __user *argp) 519 { 520 struct device_node *dp; 521 phandle nd; 522 523 BUILD_BUG_ON(sizeof(phandle) != sizeof(int)); 524 525 if (copy_from_user(&nd, argp, sizeof(phandle))) 526 return -EFAULT; 527 528 if (nd == 0) { 529 if (cmd != OPIOCGETNEXT) 530 return -EINVAL; 531 dp = of_find_node_by_path("/"); 532 } else { 533 dp = of_find_node_by_phandle(nd); 534 nd = 0; 535 if (dp) { 536 if (cmd == OPIOCGETNEXT) 537 dp = dp->sibling; 538 else 539 dp = dp->child; 540 } 541 } 542 if (dp) 543 nd = dp->phandle; 544 if (copy_to_user(argp, &nd, sizeof(phandle))) 545 return -EFAULT; 546 547 return 0; 548 } 549 550 static int openprom_bsd_ioctl(struct inode * inode, struct file * file, 551 unsigned int cmd, unsigned long arg) 552 { 553 DATA *data = (DATA *) file->private_data; 554 void __user *argp = (void __user *)arg; 555 int err; 556 557 switch (cmd) { 558 case OPIOCGET: 559 err = opiocget(argp, data); 560 break; 561 562 case OPIOCNEXTPROP: 563 err = opiocnextprop(argp, data); 564 break; 565 566 case OPIOCSET: 567 err = opiocset(argp, data); 568 break; 569 570 case OPIOCGETOPTNODE: 571 BUILD_BUG_ON(sizeof(phandle) != sizeof(int)); 572 573 if (copy_to_user(argp, &options_node->phandle, sizeof(phandle))) 574 return -EFAULT; 575 576 return 0; 577 578 case OPIOCGETNEXT: 579 case OPIOCGETCHILD: 580 err = opiocgetnext(cmd, argp); 581 break; 582 583 default: 584 return -EINVAL; 585 586 }; 587 588 return err; 589 } 590 591 592 /* 593 * Handoff control to the correct ioctl handler. 594 */ 595 static int openprom_ioctl(struct inode * inode, struct file * file, 596 unsigned int cmd, unsigned long arg) 597 { 598 DATA *data = (DATA *) file->private_data; 599 600 switch (cmd) { 601 case OPROMGETOPT: 602 case OPROMNXTOPT: 603 if ((file->f_mode & FMODE_READ) == 0) 604 return -EPERM; 605 return openprom_sunos_ioctl(inode, file, cmd, arg, 606 options_node); 607 608 case OPROMSETOPT: 609 case OPROMSETOPT2: 610 if ((file->f_mode & FMODE_WRITE) == 0) 611 return -EPERM; 612 return openprom_sunos_ioctl(inode, file, cmd, arg, 613 options_node); 614 615 case OPROMNEXT: 616 case OPROMCHILD: 617 case OPROMGETPROP: 618 case OPROMNXTPROP: 619 if ((file->f_mode & FMODE_READ) == 0) 620 return -EPERM; 621 return openprom_sunos_ioctl(inode, file, cmd, arg, 622 data->current_node); 623 624 case OPROMU2P: 625 case OPROMGETCONS: 626 case OPROMGETFBNAME: 627 case OPROMGETBOOTARGS: 628 case OPROMSETCUR: 629 case OPROMPCI2NODE: 630 case OPROMPATH2NODE: 631 if ((file->f_mode & FMODE_READ) == 0) 632 return -EPERM; 633 return openprom_sunos_ioctl(inode, file, cmd, arg, NULL); 634 635 case OPIOCGET: 636 case OPIOCNEXTPROP: 637 case OPIOCGETOPTNODE: 638 case OPIOCGETNEXT: 639 case OPIOCGETCHILD: 640 if ((file->f_mode & FMODE_READ) == 0) 641 return -EBADF; 642 return openprom_bsd_ioctl(inode,file,cmd,arg); 643 644 case OPIOCSET: 645 if ((file->f_mode & FMODE_WRITE) == 0) 646 return -EBADF; 647 return openprom_bsd_ioctl(inode,file,cmd,arg); 648 649 default: 650 return -EINVAL; 651 }; 652 } 653 654 static long openprom_compat_ioctl(struct file *file, unsigned int cmd, 655 unsigned long arg) 656 { 657 long rval = -ENOTTY; 658 659 /* 660 * SunOS/Solaris only, the NetBSD one's have embedded pointers in 661 * the arg which we'd need to clean up... 662 */ 663 switch (cmd) { 664 case OPROMGETOPT: 665 case OPROMSETOPT: 666 case OPROMNXTOPT: 667 case OPROMSETOPT2: 668 case OPROMNEXT: 669 case OPROMCHILD: 670 case OPROMGETPROP: 671 case OPROMNXTPROP: 672 case OPROMU2P: 673 case OPROMGETCONS: 674 case OPROMGETFBNAME: 675 case OPROMGETBOOTARGS: 676 case OPROMSETCUR: 677 case OPROMPCI2NODE: 678 case OPROMPATH2NODE: 679 rval = openprom_ioctl(file->f_path.dentry->d_inode, file, cmd, arg); 680 break; 681 } 682 683 return rval; 684 } 685 686 static int openprom_open(struct inode * inode, struct file * file) 687 { 688 DATA *data; 689 690 data = kmalloc(sizeof(DATA), GFP_KERNEL); 691 if (!data) 692 return -ENOMEM; 693 694 lock_kernel(); 695 data->current_node = of_find_node_by_path("/"); 696 data->lastnode = data->current_node; 697 file->private_data = (void *) data; 698 unlock_kernel(); 699 700 return 0; 701 } 702 703 static int openprom_release(struct inode * inode, struct file * file) 704 { 705 kfree(file->private_data); 706 return 0; 707 } 708 709 static const struct file_operations openprom_fops = { 710 .owner = THIS_MODULE, 711 .llseek = no_llseek, 712 .ioctl = openprom_ioctl, 713 .compat_ioctl = openprom_compat_ioctl, 714 .open = openprom_open, 715 .release = openprom_release, 716 }; 717 718 static struct miscdevice openprom_dev = { 719 .minor = SUN_OPENPROM_MINOR, 720 .name = "openprom", 721 .fops = &openprom_fops, 722 }; 723 724 static int __init openprom_init(void) 725 { 726 struct device_node *dp; 727 int err; 728 729 err = misc_register(&openprom_dev); 730 if (err) 731 return err; 732 733 dp = of_find_node_by_path("/"); 734 dp = dp->child; 735 while (dp) { 736 if (!strcmp(dp->name, "options")) 737 break; 738 dp = dp->sibling; 739 } 740 options_node = dp; 741 742 if (!options_node) { 743 misc_deregister(&openprom_dev); 744 return -EIO; 745 } 746 747 return 0; 748 } 749 750 static void __exit openprom_cleanup(void) 751 { 752 misc_deregister(&openprom_dev); 753 } 754 755 module_init(openprom_init); 756 module_exit(openprom_cleanup); 757