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