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 <linux/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_domain_bus_and_slot(0, 255 ((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 char * copyin_string(char __user *user, size_t len) 388 { 389 if ((ssize_t)len < 0 || (ssize_t)(len + 1) < 0) 390 return ERR_PTR(-EINVAL); 391 392 return memdup_user_nul(user, len); 393 } 394 395 /* 396 * NetBSD /dev/openprom ioctl calls. 397 */ 398 static int opiocget(void __user *argp, DATA *data) 399 { 400 struct opiocdesc op; 401 struct device_node *dp; 402 char *str; 403 const void *pval; 404 int err, len; 405 406 if (copy_from_user(&op, argp, sizeof(op))) 407 return -EFAULT; 408 409 dp = get_node(op.op_nodeid, data); 410 411 str = copyin_string(op.op_name, op.op_namelen); 412 if (IS_ERR(str)) 413 return PTR_ERR(str); 414 415 pval = of_get_property(dp, str, &len); 416 err = 0; 417 if (!pval || len > op.op_buflen) { 418 err = -EINVAL; 419 } else { 420 op.op_buflen = len; 421 if (copy_to_user(argp, &op, sizeof(op)) || 422 copy_to_user(op.op_buf, pval, len)) 423 err = -EFAULT; 424 } 425 kfree(str); 426 427 return err; 428 } 429 430 static int opiocnextprop(void __user *argp, DATA *data) 431 { 432 struct opiocdesc op; 433 struct device_node *dp; 434 struct property *prop; 435 char *str; 436 int len; 437 438 if (copy_from_user(&op, argp, sizeof(op))) 439 return -EFAULT; 440 441 dp = get_node(op.op_nodeid, data); 442 if (!dp) 443 return -EINVAL; 444 445 str = copyin_string(op.op_name, op.op_namelen); 446 if (IS_ERR(str)) 447 return PTR_ERR(str); 448 449 if (str[0] == '\0') { 450 prop = dp->properties; 451 } else { 452 prop = of_find_property(dp, str, NULL); 453 if (prop) 454 prop = prop->next; 455 } 456 kfree(str); 457 458 if (!prop) 459 len = 0; 460 else 461 len = prop->length; 462 463 if (len > op.op_buflen) 464 len = op.op_buflen; 465 466 if (copy_to_user(argp, &op, sizeof(op))) 467 return -EFAULT; 468 469 if (len && 470 copy_to_user(op.op_buf, prop->value, len)) 471 return -EFAULT; 472 473 return 0; 474 } 475 476 static int opiocset(void __user *argp, DATA *data) 477 { 478 struct opiocdesc op; 479 struct device_node *dp; 480 char *str, *tmp; 481 int err; 482 483 if (copy_from_user(&op, argp, sizeof(op))) 484 return -EFAULT; 485 486 dp = get_node(op.op_nodeid, data); 487 if (!dp) 488 return -EINVAL; 489 490 str = copyin_string(op.op_name, op.op_namelen); 491 if (IS_ERR(str)) 492 return PTR_ERR(str); 493 494 tmp = copyin_string(op.op_buf, op.op_buflen); 495 if (IS_ERR(tmp)) { 496 kfree(str); 497 return PTR_ERR(tmp); 498 } 499 500 err = of_set_property(dp, str, tmp, op.op_buflen); 501 502 kfree(str); 503 kfree(tmp); 504 505 return err; 506 } 507 508 static int opiocgetnext(unsigned int cmd, void __user *argp) 509 { 510 struct device_node *dp; 511 phandle nd; 512 513 BUILD_BUG_ON(sizeof(phandle) != sizeof(int)); 514 515 if (copy_from_user(&nd, argp, sizeof(phandle))) 516 return -EFAULT; 517 518 if (nd == 0) { 519 if (cmd != OPIOCGETNEXT) 520 return -EINVAL; 521 dp = of_find_node_by_path("/"); 522 } else { 523 dp = of_find_node_by_phandle(nd); 524 nd = 0; 525 if (dp) { 526 if (cmd == OPIOCGETNEXT) 527 dp = dp->sibling; 528 else 529 dp = dp->child; 530 } 531 } 532 if (dp) 533 nd = dp->phandle; 534 if (copy_to_user(argp, &nd, sizeof(phandle))) 535 return -EFAULT; 536 537 return 0; 538 } 539 540 static int openprom_bsd_ioctl(struct file * file, 541 unsigned int cmd, unsigned long arg) 542 { 543 DATA *data = file->private_data; 544 void __user *argp = (void __user *)arg; 545 int err; 546 547 mutex_lock(&openprom_mutex); 548 switch (cmd) { 549 case OPIOCGET: 550 err = opiocget(argp, data); 551 break; 552 553 case OPIOCNEXTPROP: 554 err = opiocnextprop(argp, data); 555 break; 556 557 case OPIOCSET: 558 err = opiocset(argp, data); 559 break; 560 561 case OPIOCGETOPTNODE: 562 BUILD_BUG_ON(sizeof(phandle) != sizeof(int)); 563 564 err = 0; 565 if (copy_to_user(argp, &options_node->phandle, sizeof(phandle))) 566 err = -EFAULT; 567 break; 568 569 case OPIOCGETNEXT: 570 case OPIOCGETCHILD: 571 err = opiocgetnext(cmd, argp); 572 break; 573 574 default: 575 err = -EINVAL; 576 break; 577 } 578 mutex_unlock(&openprom_mutex); 579 580 return err; 581 } 582 583 584 /* 585 * Handoff control to the correct ioctl handler. 586 */ 587 static long openprom_ioctl(struct file * file, 588 unsigned int cmd, unsigned long arg) 589 { 590 DATA *data = file->private_data; 591 592 switch (cmd) { 593 case OPROMGETOPT: 594 case OPROMNXTOPT: 595 if ((file->f_mode & FMODE_READ) == 0) 596 return -EPERM; 597 return openprom_sunos_ioctl(file, cmd, arg, 598 options_node); 599 600 case OPROMSETOPT: 601 case OPROMSETOPT2: 602 if ((file->f_mode & FMODE_WRITE) == 0) 603 return -EPERM; 604 return openprom_sunos_ioctl(file, cmd, arg, 605 options_node); 606 607 case OPROMNEXT: 608 case OPROMCHILD: 609 case OPROMGETPROP: 610 case OPROMNXTPROP: 611 if ((file->f_mode & FMODE_READ) == 0) 612 return -EPERM; 613 return openprom_sunos_ioctl(file, cmd, arg, 614 data->current_node); 615 616 case OPROMU2P: 617 case OPROMGETCONS: 618 case OPROMGETFBNAME: 619 case OPROMGETBOOTARGS: 620 case OPROMSETCUR: 621 case OPROMPCI2NODE: 622 case OPROMPATH2NODE: 623 if ((file->f_mode & FMODE_READ) == 0) 624 return -EPERM; 625 return openprom_sunos_ioctl(file, cmd, arg, NULL); 626 627 case OPIOCGET: 628 case OPIOCNEXTPROP: 629 case OPIOCGETOPTNODE: 630 case OPIOCGETNEXT: 631 case OPIOCGETCHILD: 632 if ((file->f_mode & FMODE_READ) == 0) 633 return -EBADF; 634 return openprom_bsd_ioctl(file,cmd,arg); 635 636 case OPIOCSET: 637 if ((file->f_mode & FMODE_WRITE) == 0) 638 return -EBADF; 639 return openprom_bsd_ioctl(file,cmd,arg); 640 641 default: 642 return -EINVAL; 643 }; 644 } 645 646 static long openprom_compat_ioctl(struct file *file, unsigned int cmd, 647 unsigned long arg) 648 { 649 long rval = -ENOTTY; 650 651 /* 652 * SunOS/Solaris only, the NetBSD one's have embedded pointers in 653 * the arg which we'd need to clean up... 654 */ 655 switch (cmd) { 656 case OPROMGETOPT: 657 case OPROMSETOPT: 658 case OPROMNXTOPT: 659 case OPROMSETOPT2: 660 case OPROMNEXT: 661 case OPROMCHILD: 662 case OPROMGETPROP: 663 case OPROMNXTPROP: 664 case OPROMU2P: 665 case OPROMGETCONS: 666 case OPROMGETFBNAME: 667 case OPROMGETBOOTARGS: 668 case OPROMSETCUR: 669 case OPROMPCI2NODE: 670 case OPROMPATH2NODE: 671 rval = openprom_ioctl(file, cmd, arg); 672 break; 673 } 674 675 return rval; 676 } 677 678 static int openprom_open(struct inode * inode, struct file * file) 679 { 680 DATA *data; 681 682 data = kmalloc(sizeof(DATA), GFP_KERNEL); 683 if (!data) 684 return -ENOMEM; 685 686 mutex_lock(&openprom_mutex); 687 data->current_node = of_find_node_by_path("/"); 688 data->lastnode = data->current_node; 689 file->private_data = (void *) data; 690 mutex_unlock(&openprom_mutex); 691 692 return 0; 693 } 694 695 static int openprom_release(struct inode * inode, struct file * file) 696 { 697 kfree(file->private_data); 698 return 0; 699 } 700 701 static const struct file_operations openprom_fops = { 702 .owner = THIS_MODULE, 703 .llseek = no_llseek, 704 .unlocked_ioctl = openprom_ioctl, 705 .compat_ioctl = openprom_compat_ioctl, 706 .open = openprom_open, 707 .release = openprom_release, 708 }; 709 710 static struct miscdevice openprom_dev = { 711 .minor = SUN_OPENPROM_MINOR, 712 .name = "openprom", 713 .fops = &openprom_fops, 714 }; 715 716 static int __init openprom_init(void) 717 { 718 struct device_node *dp; 719 int err; 720 721 err = misc_register(&openprom_dev); 722 if (err) 723 return err; 724 725 dp = of_find_node_by_path("/"); 726 dp = dp->child; 727 while (dp) { 728 if (!strcmp(dp->name, "options")) 729 break; 730 dp = dp->sibling; 731 } 732 options_node = dp; 733 734 if (!options_node) { 735 misc_deregister(&openprom_dev); 736 return -EIO; 737 } 738 739 return 0; 740 } 741 742 static void __exit openprom_cleanup(void) 743 { 744 misc_deregister(&openprom_dev); 745 } 746 747 module_init(openprom_init); 748 module_exit(openprom_cleanup); 749