drivers/sbus/char/openprom.c

   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 #define PROMLIB_INTERNAL
  33
  34 #include <linux/config.h>
  35 #include <linux/module.h>
  36 #include <linux/kernel.h>
  37 #include <linux/sched.h>
  38 #include <linux/errno.h>
  39 #include <linux/malloc.h>
  40 #include <linux/string.h>
  41 #include <linux/miscdevice.h>
  42 #include <linux/init.h>
  43 #include <asm/oplib.h>
  44 #include <asm/system.h>
  45 #include <asm/uaccess.h>
  46 #include <asm/openpromio.h>
  47 #ifdef CONFIG_PCI
  48 #include <linux/pci.h>
  49 #include <asm/pbm.h>
  50 #endif
  51
  52 /* Private data kept by the driver for each descriptor. */
  53 typedef struct openprom_private_data
  54 {
  55         int current_node;       /* Current node for SunOS ioctls. */
  56         int lastnode;           /* Last valid node used by BSD ioctls. */
  57 } DATA;
  58
  59 /* ID of the PROM node containing all of the EEPROM options. */
  60 static int options_node = 0;
  61
  62 /*
  63  * Copy an openpromio structure into kernel space from user space.
  64  * This routine does error checking to make sure that all memory
  65  * accesses are within bounds. A pointer to the allocated openpromio
  66  * structure will be placed in "*opp_p". Return value is the length
  67  * of the user supplied buffer.
  68  */
  69 static int copyin(struct openpromio *info, struct openpromio **opp_p)
  70 {
  71         int bufsize;
  72
  73         if (!info || !opp_p)
  74                 return -EFAULT;
  75
  76         if (get_user(bufsize, &info->oprom_size))
  77                 return -EFAULT;
  78
  79         if (bufsize == 0)
  80                 return -EINVAL;
  81
  82         /* If the bufsize is too large, just limit it.
  83          * Fix from Jason Rappleye.
  84          */
  85         if (bufsize > OPROMMAXPARAM)
  86                 bufsize = OPROMMAXPARAM;
  87
  88         if (!(*opp_p = kmalloc(sizeof(int) + bufsize + 1, GFP_KERNEL)))
  89                 return -ENOMEM;
  90         memset(*opp_p, 0, sizeof(int) + bufsize + 1);
  91
  92         if (copy_from_user(&(*opp_p)->oprom_array,
  93                            &info->oprom_array, bufsize)) {
  94                 kfree(*opp_p);
  95                 return -EFAULT;
  96         }
  97         return bufsize;
  98 }
  99
 100 static int getstrings(struct openpromio *info, struct openpromio **opp_p)
 101 {
 102         int n, bufsize;
 103         char c;
 104
 105         if (!info || !opp_p)
 106                 return -EFAULT;
 107
 108         if (!(*opp_p = kmalloc(sizeof(int) + OPROMMAXPARAM + 1, GFP_KERNEL)))
 109                 return -ENOMEM;
 110
 111         memset(*opp_p, 0, sizeof(int) + OPROMMAXPARAM + 1);
 112         (*opp_p)->oprom_size = 0;
 113
 114         n = bufsize = 0;
 115         while ((n < 2) && (bufsize < OPROMMAXPARAM)) {
 116                 if (get_user(c, &info->oprom_array[bufsize])) {
 117                         kfree(*opp_p);
 118                         return -EFAULT;
 119                 }
 120                 if (c == '\0')
 121                         n++;
 122                 (*opp_p)->oprom_array[bufsize++] = c;
 123         }
 124         if (!n) {
 125                 kfree(*opp_p);
 126                 return -EINVAL;
 127         }
 128         return bufsize;
 129 }
 130
 131 /*
 132  * Copy an openpromio structure in kernel space back to user space.
 133  */
 134 static int copyout(void *info, struct openpromio *opp, int len)
 135 {
 136         if (copy_to_user(info, opp, len))
 137                 return -EFAULT;
 138         return 0;
 139 }
 140
 141 /*
 142  *      SunOS and Solaris /dev/openprom ioctl calls.
 143  */
 144 static int openprom_sunos_ioctl(struct inode * inode, struct file * file,
 145                                 unsigned int cmd, unsigned long arg, int node)
 146 {
 147         DATA *data = (DATA *) file->private_data;
 148         char buffer[OPROMMAXPARAM+1], *buf;
 149         struct openpromio *opp;
 150         unsigned long flags;
 151         int bufsize, len, error = 0;
 152         extern char saved_command_line[];
 153         static int cnt;
 154
 155         if (cmd == OPROMSETOPT)
 156                 bufsize = getstrings((void *)arg, &opp);
 157         else
 158                 bufsize = copyin((void *)arg, &opp);
 159
 160         if (bufsize < 0)
 161                 return bufsize;
 162
 163         switch (cmd) {
 164         case OPROMGETOPT:
 165         case OPROMGETPROP:
 166                 save_and_cli(flags);
 167                 len = prom_getproplen(node, opp->oprom_array);
 168                 restore_flags(flags);
 169
 170                 if (len <= 0 || len > bufsize) {
 171                         error = copyout((void *)arg, opp, sizeof(int));
 172                         break;
 173                 }
 174
 175                 save_and_cli(flags);
 176                 len = prom_getproperty(node, opp->oprom_array, buffer, bufsize);
 177                 restore_flags(flags);
 178
 179                 memcpy(opp->oprom_array, buffer, len);
 180                 opp->oprom_array[len] = '\0';
 181                 opp->oprom_size = len;
 182
 183                 error = copyout((void *)arg, opp, sizeof(int) + bufsize);
 184                 break;
 185
 186         case OPROMNXTOPT:
 187         case OPROMNXTPROP:
 188                 save_and_cli(flags);
 189                 buf = prom_nextprop(node, opp->oprom_array, buffer);
 190                 restore_flags(flags);
 191
 192                 len = strlen(buf);
 193                 if (len == 0 || len + 1 > bufsize) {
 194                         error = copyout((void *)arg, opp, sizeof(int));
 195                         break;
 196                 }
 197
 198                 memcpy(opp->oprom_array, buf, len);
 199                 opp->oprom_array[len] = '\0';
 200                 opp->oprom_size = ++len;
 201
 202                 error = copyout((void *)arg, opp, sizeof(int) + bufsize);
 203                 break;
 204
 205         case OPROMSETOPT:
 206         case OPROMSETOPT2:
 207                 buf = opp->oprom_array + strlen(opp->oprom_array) + 1;
 208                 len = opp->oprom_array + bufsize - buf;
 209
 210                 save_and_cli(flags);
 211                 error = prom_setprop(options_node, opp->oprom_array,
 212                                      buf, len);
 213                 restore_flags(flags);
 214
 215                 if (error < 0)
 216                         error = -EINVAL;
 217                 break;
 218
 219         case OPROMNEXT:
 220         case OPROMCHILD:
 221         case OPROMSETCUR:
 222                 if (bufsize < sizeof(int)) {
 223                         error = -EINVAL;
 224                         break;
 225                 }
 226
 227                 node = *((int *) opp->oprom_array);
 228
 229                 save_and_cli(flags);
 230                 switch (cmd) {
 231                 case OPROMNEXT: node = __prom_getsibling(node); break;
 232                 case OPROMCHILD: node = __prom_getchild(node); break;
 233                 case OPROMSETCUR: break;
 234                 }
 235                 restore_flags(flags);
 236
 237                 data->current_node = node;
 238                 *((int *)opp->oprom_array) = node;
 239                 opp->oprom_size = sizeof(int);
 240
 241                 error = copyout((void *)arg, opp, bufsize + sizeof(int));
 242                 break;
 243
 244         case OPROMPCI2NODE:
 245                 error = -EINVAL;
 246
 247                 if (bufsize >= 2*sizeof(int)) {
 248 #ifdef CONFIG_PCI
 249                         struct pci_dev *pdev;
 250                         struct pcidev_cookie *pcp;
 251                         pdev = pci_find_slot (((int *) opp->oprom_array)[0],
 252                                               ((int *) opp->oprom_array)[1]);
 253
 254                         pcp = pdev->sysdata;
 255                         if (pcp != NULL && pcp->prom_node != -1 && pcp->prom_node) {
 256                                 node = pcp->prom_node;
 257                                 data->current_node = node;
 258                                 *((int *)opp->oprom_array) = node;
 259                                 opp->oprom_size = sizeof(int);
 260                                 error = copyout((void *)arg, opp, bufsize + sizeof(int));
 261                         }
 262 #endif
 263                 }
 264                 break;
 265
 266         case OPROMPATH2NODE:
 267                 save_and_cli(flags);
 268                 node = prom_finddevice(opp->oprom_array);
 269                 restore_flags(flags);
 270                 data->current_node = node;
 271                 *((int *)opp->oprom_array) = node;
 272                 opp->oprom_size = sizeof(int);
 273
 274                 error = copyout((void *)arg, opp, bufsize + sizeof(int));
 275                 break;
 276
 277         case OPROMGETBOOTARGS:
 278                 buf = saved_command_line;
 279
 280                 len = strlen(buf);
 281
 282                 if (len > bufsize) {
 283                         error = -EINVAL;
 284                         break;
 285                 }
 286
 287                 strcpy(opp->oprom_array, buf);
 288                 opp->oprom_size = len;
 289
 290                 error = copyout((void *)arg, opp, bufsize + sizeof(int));
 291                 break;
 292
 293         case OPROMU2P:
 294         case OPROMGETCONS:
 295         case OPROMGETFBNAME:
 296                 if (cnt++ < 10)
 297                         printk(KERN_INFO "openprom_sunos_ioctl: unimplemented ioctl\n");
 298                 error = -EINVAL;
 299                 break;
 300         default:
 301                 if (cnt++ < 10)
 302                         printk(KERN_INFO "openprom_sunos_ioctl: cmd 0x%X, arg 0x%lX\n", cmd, arg);
 303                 error = -EINVAL;
 304                 break;
 305         }
 306
 307         kfree(opp);
 308         return error;
 309 }
 310
 311
 312 /* Return nonzero if a specific node is in the PROM device tree. */
 313 static int intree(int root, int node)
 314 {
 315         for (; root != 0; root = prom_getsibling(root))
 316                 if (root == node || intree(prom_getchild(root),node))
 317                         return 1;
 318         return 0;
 319 }
 320
 321 /* Return nonzero if a specific node is "valid". */
 322 static int goodnode(int n, DATA *data)
 323 {
 324         if (n == data->lastnode || n == prom_root_node || n == options_node)
 325                 return 1;
 326         if (n == 0 || n == -1 || !intree(prom_root_node,n))
 327                 return 0;
 328         data->lastnode = n;
 329         return 1;
 330 }
 331
 332 /* Copy in a whole string from userspace into kernelspace. */
 333 static int copyin_string(char *user, size_t len, char **ptr)
 334 {
 335         char *tmp;
 336
 337         tmp = kmalloc(len + 1, GFP_KERNEL);
 338         if (!tmp)
 339                 return -ENOMEM;
 340
 341         if(copy_from_user(tmp, user, len)) {
 342                 kfree(tmp);
 343                 return -EFAULT;
 344         }
 345
 346         tmp[len] = '\0';
 347
 348         *ptr = tmp;
 349
 350         return 0;
 351 }
 352
 353 /*
 354  *      NetBSD /dev/openprom ioctl calls.
 355  */
 356 static int openprom_bsd_ioctl(struct inode * inode, struct file * file,
 357                               unsigned int cmd, unsigned long arg)
 358 {
 359         DATA *data = (DATA *) file->private_data;
 360         struct opiocdesc op;
 361         unsigned long flags;
 362         int error, node, len;
 363         char *str, *tmp;
 364         char buffer[64];
 365         static int cnt;
 366
 367         switch (cmd) {
 368         case OPIOCGET:
 369                 if (copy_from_user(&op, (void *)arg, sizeof(op)))
 370                         return -EFAULT;
 371
 372                 if (!goodnode(op.op_nodeid,data))
 373                         return -EINVAL;
 374
 375                 error = copyin_string(op.op_name, op.op_namelen, &str);
 376                 if (error)
 377                         return error;
 378
 379                 save_and_cli(flags);
 380                 len = prom_getproplen(op.op_nodeid,str);
 381                 restore_flags(flags);
 382
 383                 if (len > op.op_buflen) {
 384                         kfree(str);
 385                         return -ENOMEM;
 386                 }
 387
 388                 op.op_buflen = len;
 389
 390                 if (len <= 0) {
 391                         kfree(str);
 392                         /* Verified by the above copy_from_user */
 393                         if (__copy_to_user((void *)arg, &op,
 394                                        sizeof(op)))
 395                                 return -EFAULT;
 396                         return 0;
 397                 }
 398
 399                 tmp = kmalloc(len + 1, GFP_KERNEL);
 400                 if (!tmp) {
 401                         kfree(str);
 402                         return -ENOMEM;
 403                 }
 404
 405                 save_and_cli(flags);
 406                 prom_getproperty(op.op_nodeid, str, tmp, len);
 407                 restore_flags(flags);
 408
 409                 tmp[len] = '\0';
 410
 411                 error = __copy_to_user((void *)arg, &op, sizeof(op));
 412                 if (!error)
 413                         error = copy_to_user(op.op_buf, tmp, len);
 414
 415                 kfree(tmp);
 416                 kfree(str);
 417
 418                 return error;
 419
 420         case OPIOCNEXTPROP:
 421                 if (copy_from_user(&op, (void *)arg, sizeof(op)))
 422                         return -EFAULT;
 423
 424                 if (!goodnode(op.op_nodeid,data))
 425                         return -EINVAL;
 426
 427                 error = copyin_string(op.op_name, op.op_namelen, &str);
 428                 if (error)
 429                         return error;
 430
 431                 save_and_cli(flags);
 432                 tmp = prom_nextprop(op.op_nodeid,str,buffer);
 433                 restore_flags(flags);
 434
 435                 if (tmp) {
 436                         len = strlen(tmp);
 437                         if (len > op.op_buflen)
 438                                 len = op.op_buflen;
 439                         else
 440                                 op.op_buflen = len;
 441                 } else {
 442                         len = op.op_buflen = 0;
 443                 }
 444
 445                 error = verify_area(VERIFY_WRITE, (void *)arg, sizeof(op));
 446                 if (error) {
 447                         kfree(str);
 448                         return error;
 449                 }
 450
 451                 error = verify_area(VERIFY_WRITE, op.op_buf, len);
 452                 if (error) {
 453                         kfree(str);
 454                         return error;
 455                 }
 456
 457                 error = __copy_to_user((void *)arg, &op, sizeof(op));
 458                 if (!error) error = __copy_to_user(op.op_buf, tmp, len);
 459
 460                 kfree(str);
 461
 462                 return error;
 463
 464         case OPIOCSET:
 465                 if (copy_from_user(&op, (void *)arg, sizeof(op)))
 466                         return -EFAULT;
 467
 468                 if (!goodnode(op.op_nodeid,data))
 469                         return -EINVAL;
 470
 471                 error = copyin_string(op.op_name, op.op_namelen, &str);
 472                 if (error)
 473                         return error;
 474
 475                 error = copyin_string(op.op_buf, op.op_buflen, &tmp);
 476                 if (error) {
 477                         kfree(str);
 478                         return error;
 479                 }
 480
 481                 save_and_cli(flags);
 482                 len = prom_setprop(op.op_nodeid,str,tmp,op.op_buflen+1);
 483                 restore_flags(flags);
 484
 485                 if (len != op.op_buflen)
 486                         return -EINVAL;
 487
 488                 kfree(str);
 489                 kfree(tmp);
 490
 491                 return 0;
 492
 493         case OPIOCGETOPTNODE:
 494                 if (copy_to_user((void *)arg, &options_node, sizeof(int)))
 495                         return -EFAULT;
 496                 return 0;
 497
 498         case OPIOCGETNEXT:
 499         case OPIOCGETCHILD:
 500                 if (copy_from_user(&node, (void *)arg, sizeof(int)))
 501                         return -EFAULT;
 502
 503                 save_and_cli(flags);
 504                 if (cmd == OPIOCGETNEXT)
 505                         node = __prom_getsibling(node);
 506                 else
 507                         node = __prom_getchild(node);
 508                 restore_flags(flags);
 509
 510                 if (__copy_to_user((void *)arg, &node, sizeof(int)))
 511                         return -EFAULT;
 512
 513                 return 0;
 514
 515         default:
 516                 if (cnt++ < 10)
 517                         printk(KERN_INFO "openprom_bsd_ioctl: cmd 0x%X\n", cmd);
 518                 return -EINVAL;
 519
 520         }
 521 }
 522
 523
 524 /*
 525  *      Handoff control to the correct ioctl handler.
 526  */
 527 static int openprom_ioctl(struct inode * inode, struct file * file,
 528                           unsigned int cmd, unsigned long arg)
 529 {
 530         DATA *data = (DATA *) file->private_data;
 531         static int cnt;
 532
 533         switch (cmd) {
 534         case OPROMGETOPT:
 535         case OPROMNXTOPT:
 536                 if ((file->f_mode & FMODE_READ) == 0)
 537                         return -EPERM;
 538                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 539                                             options_node);
 540
 541         case OPROMSETOPT:
 542         case OPROMSETOPT2:
 543                 if ((file->f_mode & FMODE_WRITE) == 0)
 544                         return -EPERM;
 545                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 546                                             options_node);
 547
 548         case OPROMNEXT:
 549         case OPROMCHILD:
 550         case OPROMGETPROP:
 551         case OPROMNXTPROP:
 552                 if ((file->f_mode & FMODE_READ) == 0)
 553                         return -EPERM;
 554                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 555                                             data->current_node);
 556
 557         case OPROMU2P:
 558         case OPROMGETCONS:
 559         case OPROMGETFBNAME:
 560         case OPROMGETBOOTARGS:
 561         case OPROMSETCUR:
 562         case OPROMPCI2NODE:
 563         case OPROMPATH2NODE:
 564                 if ((file->f_mode & FMODE_READ) == 0)
 565                         return -EPERM;
 566                 return openprom_sunos_ioctl(inode, file, cmd, arg, 0);
 567
 568         case OPIOCGET:
 569         case OPIOCNEXTPROP:
 570         case OPIOCGETOPTNODE:
 571         case OPIOCGETNEXT:
 572         case OPIOCGETCHILD:
 573                 if ((file->f_mode & FMODE_READ) == 0)
 574                         return -EBADF;
 575                 return openprom_bsd_ioctl(inode,file,cmd,arg);
 576
 577         case OPIOCSET:
 578                 if ((file->f_mode & FMODE_WRITE) == 0)
 579                         return -EBADF;
 580                 return openprom_bsd_ioctl(inode,file,cmd,arg);
 581
 582         default:
 583                 if (cnt++ < 10)
 584                         printk("openprom_ioctl: cmd 0x%X, arg 0x%lX\n", cmd, arg);
 585                 return -EINVAL;
 586         }
 587 }
 588
 589 static long long openprom_lseek(struct file * file, long long offset, int origin)
 590 {
 591         return -ESPIPE;
 592 }
 593
 594 static int openprom_open(struct inode * inode, struct file * file)
 595 {
 596         DATA *data;
 597
 598         data = (DATA *) kmalloc(sizeof(DATA), GFP_KERNEL);
 599         if (!data)
 600                 return -ENOMEM;
 601
 602         data->current_node = prom_root_node;
 603         data->lastnode = prom_root_node;
 604         file->private_data = (void *)data;
 605
 606         return 0;
 607 }
 608
 609 static int openprom_release(struct inode * inode, struct file * file)
 610 {
 611         kfree(file->private_data);
 612         return 0;
 613 }
 614
 615 static struct file_operations openprom_fops = {
 616         owner:          THIS_MODULE,
 617         llseek:         openprom_lseek,
 618         ioctl:          openprom_ioctl,
 619         open:           openprom_open,
 620         release:        openprom_release,
 621 };
 622
 623 static struct miscdevice openprom_dev = {
 624         SUN_OPENPROM_MINOR, "openprom", &openprom_fops
 625 };
 626
 627 EXPORT_NO_SYMBOLS;
 628
 629 #ifdef MODULE
 630 int init_module(void)
 631 #else
 632 int __init openprom_init(void)
 633 #endif
 634 {
 635         unsigned long flags;
 636         int error;
 637
 638         error = misc_register(&openprom_dev);
 639         if (error) {
 640                 printk(KERN_ERR "openprom: unable to get misc minor\n");
 641                 return error;
 642         }
 643
 644         save_and_cli(flags);
 645         options_node = prom_getchild(prom_root_node);
 646         options_node = prom_searchsiblings(options_node,"options");
 647         restore_flags(flags);
 648
 649         if (options_node == 0 || options_node == -1) {
 650                 printk(KERN_ERR "openprom: unable to find options node\n");
 651                 misc_deregister(&openprom_dev);
 652                 return -EIO;
 653         }
 654
 655         return 0;
 656 }
 657
 658 #ifdef MODULE
 659 void cleanup_module(void)
 660 {
 661         misc_deregister(&openprom_dev);
 662 }
 663 #endif