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