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 #include <linux/module.h>
  33 #include <linux/kernel.h>
  34 #include <linux/sched.h>
  35 #include <linux/errno.h>
  36 #include <linux/slab.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/system.h>
  44 #include <asm/uaccess.h>
  45 #include <asm/openpromio.h>
  46 #ifdef CONFIG_PCI
  47 #include <linux/pci.h>
  48 #include <asm/pbm.h>
  49 #endif
  50
  51 MODULE_AUTHOR("Thomas K. Dyas (tdyas@noc.rutgers.edu) and Eddie C. Dost  (ecd@skynet.be)");
  52 MODULE_DESCRIPTION("OPENPROM Configuration Driver");
  53 MODULE_LICENSE("GPL");
  54 MODULE_VERSION("1.0");
  55
  56 /* Private data kept by the driver for each descriptor. */
  57 typedef struct openprom_private_data
  58 {
  59         struct device_node *current_node; /* Current node for SunOS ioctls. */
  60         struct device_node *lastnode; /* Last valid node used by BSD ioctls. */
  61 } DATA;
  62
  63 /* ID of the PROM node containing all of the EEPROM options. */
  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         void *pval;
 146         int len;
 147
 148         pval = of_get_property(dp, op->oprom_array, &len);
 149         if (!pval || len <= 0 || len > bufsize)
 150                 return copyout(argp, op, sizeof(int));
 151
 152         memcpy(op->oprom_array, pval, len);
 153         op->oprom_array[len] = '\0';
 154         op->oprom_size = len;
 155
 156         return copyout(argp, op, sizeof(int) + bufsize);
 157 }
 158
 159 static int opromnxtprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize)
 160 {
 161         struct property *prop;
 162         int len;
 163
 164         if (op->oprom_array[0] == '\0') {
 165                 prop = dp->properties;
 166                 if (!prop)
 167                         return copyout(argp, op, sizeof(int));
 168                 len = strlen(prop->name);
 169         } else {
 170                 prop = of_find_property(dp, op->oprom_array, NULL);
 171
 172                 if (!prop ||
 173                     !prop->next ||
 174                     (len = strlen(prop->next->name)) + 1 > bufsize)
 175                         return copyout(argp, op, sizeof(int));
 176
 177                 prop = prop->next;
 178         }
 179
 180         memcpy(op->oprom_array, prop->name, len);
 181         op->oprom_array[len] = '\0';
 182         op->oprom_size = ++len;
 183
 184         return copyout(argp, op, sizeof(int) + bufsize);
 185 }
 186
 187 static int opromsetopt(struct device_node *dp, struct openpromio *op, int bufsize)
 188 {
 189         char *buf = op->oprom_array + strlen(op->oprom_array) + 1;
 190         int len = op->oprom_array + bufsize - buf;
 191
 192         return of_set_property(options_node, op->oprom_array, buf, len);
 193 }
 194
 195 static int opromnext(void __user *argp, unsigned int cmd, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
 196 {
 197         phandle ph;
 198
 199         BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
 200
 201         if (bufsize < sizeof(phandle))
 202                 return -EINVAL;
 203
 204         ph = *((int *) op->oprom_array);
 205         if (ph) {
 206                 dp = of_find_node_by_phandle(ph);
 207                 if (!dp)
 208                         return -EINVAL;
 209
 210                 switch (cmd) {
 211                 case OPROMNEXT:
 212                         dp = dp->sibling;
 213                         break;
 214
 215                 case OPROMCHILD:
 216                         dp = dp->child;
 217                         break;
 218
 219                 case OPROMSETCUR:
 220                 default:
 221                         break;
 222                 };
 223         } else {
 224                 /* Sibling of node zero is the root node.  */
 225                 if (cmd != OPROMNEXT)
 226                         return -EINVAL;
 227
 228                 dp = of_find_node_by_path("/");
 229         }
 230
 231         ph = 0;
 232         if (dp)
 233                 ph = dp->node;
 234
 235         data->current_node = dp;
 236         *((int *) op->oprom_array) = ph;
 237         op->oprom_size = sizeof(phandle);
 238
 239         return copyout(argp, op, bufsize + sizeof(int));
 240 }
 241
 242 static int oprompci2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
 243 {
 244         int err = -EINVAL;
 245
 246         if (bufsize >= 2*sizeof(int)) {
 247 #ifdef CONFIG_PCI
 248                 struct pci_dev *pdev;
 249                 struct pcidev_cookie *pcp;
 250                 pdev = pci_find_slot (((int *) op->oprom_array)[0],
 251                                       ((int *) op->oprom_array)[1]);
 252
 253                 pcp = pdev->sysdata;
 254                 if (pcp != NULL) {
 255                         dp = pcp->prom_node;
 256                         data->current_node = dp;
 257                         *((int *)op->oprom_array) = dp->node;
 258                         op->oprom_size = sizeof(int);
 259                         err = copyout(argp, op, bufsize + sizeof(int));
 260                 }
 261 #endif
 262         }
 263
 264         return err;
 265 }
 266
 267 static int oprompath2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
 268 {
 269         dp = of_find_node_by_path(op->oprom_array);
 270         data->current_node = dp;
 271         *((int *)op->oprom_array) = dp->node;
 272         op->oprom_size = sizeof(int);
 273
 274         return copyout(argp, op, bufsize + sizeof(int));
 275 }
 276
 277 static int opromgetbootargs(void __user *argp, struct openpromio *op, int bufsize)
 278 {
 279         char *buf = saved_command_line;
 280         int len = strlen(buf);
 281
 282         if (len > bufsize)
 283                 return -EINVAL;
 284
 285         strcpy(op->oprom_array, buf);
 286         op->oprom_size = len;
 287
 288         return copyout(argp, op, bufsize + sizeof(int));
 289 }
 290
 291 /*
 292  *      SunOS and Solaris /dev/openprom ioctl calls.
 293  */
 294 static int openprom_sunos_ioctl(struct inode * inode, struct file * file,
 295                                 unsigned int cmd, unsigned long arg,
 296                                 struct device_node *dp)
 297 {
 298         DATA *data = file->private_data;
 299         struct openpromio *opp;
 300         int bufsize, error = 0;
 301         static int cnt;
 302         void __user *argp = (void __user *)arg;
 303
 304         if (cmd == OPROMSETOPT)
 305                 bufsize = getstrings(argp, &opp);
 306         else
 307                 bufsize = copyin(argp, &opp);
 308
 309         if (bufsize < 0)
 310                 return bufsize;
 311
 312         switch (cmd) {
 313         case OPROMGETOPT:
 314         case OPROMGETPROP:
 315                 error = opromgetprop(argp, dp, opp, bufsize);
 316                 break;
 317
 318         case OPROMNXTOPT:
 319         case OPROMNXTPROP:
 320                 error = opromnxtprop(argp, dp, opp, bufsize);
 321                 break;
 322
 323         case OPROMSETOPT:
 324         case OPROMSETOPT2:
 325                 error = opromsetopt(dp, opp, bufsize);
 326                 break;
 327
 328         case OPROMNEXT:
 329         case OPROMCHILD:
 330         case OPROMSETCUR:
 331                 error = opromnext(argp, cmd, dp, opp, bufsize, data);
 332                 break;
 333
 334         case OPROMPCI2NODE:
 335                 error = oprompci2node(argp, dp, opp, bufsize, data);
 336                 break;
 337
 338         case OPROMPATH2NODE:
 339                 error = oprompath2node(argp, dp, opp, bufsize, data);
 340                 break;
 341
 342         case OPROMGETBOOTARGS:
 343                 error = opromgetbootargs(argp, opp, bufsize);
 344                 break;
 345
 346         case OPROMU2P:
 347         case OPROMGETCONS:
 348         case OPROMGETFBNAME:
 349                 if (cnt++ < 10)
 350                         printk(KERN_INFO "openprom_sunos_ioctl: unimplemented ioctl\n");
 351                 error = -EINVAL;
 352                 break;
 353         default:
 354                 if (cnt++ < 10)
 355                         printk(KERN_INFO "openprom_sunos_ioctl: cmd 0x%X, arg 0x%lX\n", cmd, arg);
 356                 error = -EINVAL;
 357                 break;
 358         }
 359
 360         kfree(opp);
 361         return error;
 362 }
 363
 364 static struct device_node *get_node(phandle n, DATA *data)
 365 {
 366         struct device_node *dp = of_find_node_by_phandle(n);
 367
 368         if (dp)
 369                 data->lastnode = dp;
 370
 371         return dp;
 372 }
 373
 374 /* Copy in a whole string from userspace into kernelspace. */
 375 static int copyin_string(char __user *user, size_t len, char **ptr)
 376 {
 377         char *tmp;
 378
 379         if ((ssize_t)len < 0 || (ssize_t)(len + 1) < 0)
 380                 return -EINVAL;
 381
 382         tmp = kmalloc(len + 1, GFP_KERNEL);
 383         if (!tmp)
 384                 return -ENOMEM;
 385
 386         if (copy_from_user(tmp, user, len)) {
 387                 kfree(tmp);
 388                 return -EFAULT;
 389         }
 390
 391         tmp[len] = '\0';
 392
 393         *ptr = tmp;
 394
 395         return 0;
 396 }
 397
 398 /*
 399  *      NetBSD /dev/openprom ioctl calls.
 400  */
 401 static int opiocget(void __user *argp, DATA *data)
 402 {
 403         struct opiocdesc op;
 404         struct device_node *dp;
 405         char *str;
 406         void *pval;
 407         int err, len;
 408
 409         if (copy_from_user(&op, argp, sizeof(op)))
 410                 return -EFAULT;
 411
 412         dp = get_node(op.op_nodeid, data);
 413
 414         err = copyin_string(op.op_name, op.op_namelen, &str);
 415         if (err)
 416                 return err;
 417
 418         pval = of_get_property(dp, str, &len);
 419         err = 0;
 420         if (!pval || len > op.op_buflen) {
 421                 err = -EINVAL;
 422         } else {
 423                 op.op_buflen = len;
 424                 if (copy_to_user(argp, &op, sizeof(op)) ||
 425                     copy_to_user(op.op_buf, pval, len))
 426                         err = -EFAULT;
 427         }
 428         kfree(str);
 429
 430         return err;
 431 }
 432
 433 static int opiocnextprop(void __user *argp, DATA *data)
 434 {
 435         struct opiocdesc op;
 436         struct device_node *dp;
 437         struct property *prop;
 438         char *str;
 439         int err, len;
 440
 441         if (copy_from_user(&op, argp, sizeof(op)))
 442                 return -EFAULT;
 443
 444         dp = get_node(op.op_nodeid, data);
 445         if (!dp)
 446                 return -EINVAL;
 447
 448         err = copyin_string(op.op_name, op.op_namelen, &str);
 449         if (err)
 450                 return err;
 451
 452         if (str[0] == '\0') {
 453                 prop = dp->properties;
 454         } else {
 455                 prop = of_find_property(dp, str, NULL);
 456                 if (prop)
 457                         prop = prop->next;
 458         }
 459         kfree(str);
 460
 461         if (!prop)
 462                 len = 0;
 463         else
 464                 len = prop->length;
 465
 466         if (len > op.op_buflen)
 467                 len = op.op_buflen;
 468
 469         if (copy_to_user(argp, &op, sizeof(op)))
 470                 return -EFAULT;
 471
 472         if (len &&
 473             copy_to_user(op.op_buf, prop->value, len))
 474                 return -EFAULT;
 475
 476         return 0;
 477 }
 478
 479 static int opiocset(void __user *argp, DATA *data)
 480 {
 481         struct opiocdesc op;
 482         struct device_node *dp;
 483         char *str, *tmp;
 484         int err;
 485
 486         if (copy_from_user(&op, argp, sizeof(op)))
 487                 return -EFAULT;
 488
 489         dp = get_node(op.op_nodeid, data);
 490         if (!dp)
 491                 return -EINVAL;
 492
 493         err = copyin_string(op.op_name, op.op_namelen, &str);
 494         if (err)
 495                 return err;
 496
 497         err = copyin_string(op.op_buf, op.op_buflen, &tmp);
 498         if (err) {
 499                 kfree(str);
 500                 return err;
 501         }
 502
 503         err = of_set_property(dp, str, tmp, op.op_buflen);
 504
 505         kfree(str);
 506         kfree(tmp);
 507
 508         return err;
 509 }
 510
 511 static int opiocgetnext(unsigned int cmd, void __user *argp)
 512 {
 513         struct device_node *dp;
 514         phandle nd;
 515
 516         BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
 517
 518         if (copy_from_user(&nd, argp, sizeof(phandle)))
 519                 return -EFAULT;
 520
 521         if (nd == 0) {
 522                 if (cmd != OPIOCGETNEXT)
 523                         return -EINVAL;
 524                 dp = of_find_node_by_path("/");
 525         } else {
 526                 dp = of_find_node_by_phandle(nd);
 527                 nd = 0;
 528                 if (dp) {
 529                         if (cmd == OPIOCGETNEXT)
 530                                 dp = dp->sibling;
 531                         else
 532                                 dp = dp->child;
 533                 }
 534         }
 535         if (dp)
 536                 nd = dp->node;
 537         if (copy_to_user(argp, &nd, sizeof(phandle)))
 538                 return -EFAULT;
 539
 540         return 0;
 541 }
 542
 543 static int openprom_bsd_ioctl(struct inode * inode, struct file * file,
 544                               unsigned int cmd, unsigned long arg)
 545 {
 546         DATA *data = (DATA *) file->private_data;
 547         void __user *argp = (void __user *)arg;
 548         int err;
 549
 550         switch (cmd) {
 551         case OPIOCGET:
 552                 err = opiocget(argp, data);
 553                 break;
 554
 555         case OPIOCNEXTPROP:
 556                 err = opiocnextprop(argp, data);
 557                 break;
 558
 559         case OPIOCSET:
 560                 err = opiocset(argp, data);
 561                 break;
 562
 563         case OPIOCGETOPTNODE:
 564                 BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
 565
 566                 if (copy_to_user(argp, &options_node->node, sizeof(phandle)))
 567                         return -EFAULT;
 568
 569                 return 0;
 570
 571         case OPIOCGETNEXT:
 572         case OPIOCGETCHILD:
 573                 err = opiocgetnext(cmd, argp);
 574                 break;
 575
 576         default:
 577                 return -EINVAL;
 578
 579         };
 580
 581         return err;
 582 }
 583
 584
 585 /*
 586  *      Handoff control to the correct ioctl handler.
 587  */
 588 static int openprom_ioctl(struct inode * inode, struct file * file,
 589                           unsigned int cmd, unsigned long arg)
 590 {
 591         DATA *data = (DATA *) file->private_data;
 592
 593         switch (cmd) {
 594         case OPROMGETOPT:
 595         case OPROMNXTOPT:
 596                 if ((file->f_mode & FMODE_READ) == 0)
 597                         return -EPERM;
 598                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 599                                             options_node);
 600
 601         case OPROMSETOPT:
 602         case OPROMSETOPT2:
 603                 if ((file->f_mode & FMODE_WRITE) == 0)
 604                         return -EPERM;
 605                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 606                                             options_node);
 607
 608         case OPROMNEXT:
 609         case OPROMCHILD:
 610         case OPROMGETPROP:
 611         case OPROMNXTPROP:
 612                 if ((file->f_mode & FMODE_READ) == 0)
 613                         return -EPERM;
 614                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 615                                             data->current_node);
 616
 617         case OPROMU2P:
 618         case OPROMGETCONS:
 619         case OPROMGETFBNAME:
 620         case OPROMGETBOOTARGS:
 621         case OPROMSETCUR:
 622         case OPROMPCI2NODE:
 623         case OPROMPATH2NODE:
 624                 if ((file->f_mode & FMODE_READ) == 0)
 625                         return -EPERM;
 626                 return openprom_sunos_ioctl(inode, file, cmd, arg, 0);
 627
 628         case OPIOCGET:
 629         case OPIOCNEXTPROP:
 630         case OPIOCGETOPTNODE:
 631         case OPIOCGETNEXT:
 632         case OPIOCGETCHILD:
 633                 if ((file->f_mode & FMODE_READ) == 0)
 634                         return -EBADF;
 635                 return openprom_bsd_ioctl(inode,file,cmd,arg);
 636
 637         case OPIOCSET:
 638                 if ((file->f_mode & FMODE_WRITE) == 0)
 639                         return -EBADF;
 640                 return openprom_bsd_ioctl(inode,file,cmd,arg);
 641
 642         default:
 643                 return -EINVAL;
 644         };
 645 }
 646
 647 static long openprom_compat_ioctl(struct file *file, unsigned int cmd,
 648                 unsigned long arg)
 649 {
 650         long rval = -ENOTTY;
 651
 652         /*
 653          * SunOS/Solaris only, the NetBSD one's have embedded pointers in
 654          * the arg which we'd need to clean up...
 655          */
 656         switch (cmd) {
 657         case OPROMGETOPT:
 658         case OPROMSETOPT:
 659         case OPROMNXTOPT:
 660         case OPROMSETOPT2:
 661         case OPROMNEXT:
 662         case OPROMCHILD:
 663         case OPROMGETPROP:
 664         case OPROMNXTPROP:
 665         case OPROMU2P:
 666         case OPROMGETCONS:
 667         case OPROMGETFBNAME:
 668         case OPROMGETBOOTARGS:
 669         case OPROMSETCUR:
 670         case OPROMPCI2NODE:
 671         case OPROMPATH2NODE:
 672                 rval = openprom_ioctl(file->f_dentry->d_inode, file, cmd, arg);
 673                 break;
 674         }
 675
 676         return rval;
 677 }
 678
 679 static int openprom_open(struct inode * inode, struct file * file)
 680 {
 681         DATA *data;
 682
 683         data = kmalloc(sizeof(DATA), GFP_KERNEL);
 684         if (!data)
 685                 return -ENOMEM;
 686
 687         data->current_node = of_find_node_by_path("/");
 688         data->lastnode = data->current_node;
 689         file->private_data = (void *) data;
 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 struct file_operations openprom_fops = {
 701         .owner =        THIS_MODULE,
 702         .llseek =       no_llseek,
 703         .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);