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