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/errno.h>
  35 #include <linux/slab.h>
  36 #include <linux/string.h>
  37 #include <linux/miscdevice.h>
  38 #include <linux/init.h>
  39 #include <linux/fs.h>
  40 #include <asm/oplib.h>
  41 #include <asm/prom.h>
  42 #include <asm/system.h>
  43 #include <asm/uaccess.h>
  44 #include <asm/openpromio.h>
  45 #ifdef CONFIG_PCI
  46 #include <linux/pci.h>
  47 #endif
  48
  49 MODULE_AUTHOR("Thomas K. Dyas (tdyas@noc.rutgers.edu) and Eddie C. Dost  (ecd@skynet.be)");
  50 MODULE_DESCRIPTION("OPENPROM Configuration Driver");
  51 MODULE_LICENSE("GPL");
  52 MODULE_VERSION("1.0");
  53
  54 /* Private data kept by the driver for each descriptor. */
  55 typedef struct openprom_private_data
  56 {
  57         struct device_node *current_node; /* Current node for SunOS ioctls. */
  58         struct device_node *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 struct device_node *options_node;
  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 = kzalloc(sizeof(int) + bufsize + 1, GFP_KERNEL)))
  91                 return -ENOMEM;
  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 = kzalloc(sizeof(int) + OPROMMAXPARAM + 1, GFP_KERNEL)))
 110                 return -ENOMEM;
 111
 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 __user *info, struct openpromio *opp, int len)
 135 {
 136         if (copy_to_user(info, opp, len))
 137                 return -EFAULT;
 138         return 0;
 139 }
 140
 141 static int opromgetprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize)
 142 {
 143         const void *pval;
 144         int len;
 145
 146         if (!dp ||
 147             !(pval = of_get_property(dp, op->oprom_array, &len)) ||
 148             len <= 0 || len > bufsize)
 149                 return copyout(argp, op, sizeof(int));
 150
 151         memcpy(op->oprom_array, pval, len);
 152         op->oprom_array[len] = '\0';
 153         op->oprom_size = len;
 154
 155         return copyout(argp, op, sizeof(int) + bufsize);
 156 }
 157
 158 static int opromnxtprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize)
 159 {
 160         struct property *prop;
 161         int len;
 162
 163         if (!dp)
 164                 return copyout(argp, op, sizeof(int));
 165         if (op->oprom_array[0] == '\0') {
 166                 prop = dp->properties;
 167                 if (!prop)
 168                         return copyout(argp, op, sizeof(int));
 169                 len = strlen(prop->name);
 170         } else {
 171                 prop = of_find_property(dp, op->oprom_array, NULL);
 172
 173                 if (!prop ||
 174                     !prop->next ||
 175                     (len = strlen(prop->next->name)) + 1 > bufsize)
 176                         return copyout(argp, op, sizeof(int));
 177
 178                 prop = prop->next;
 179         }
 180
 181         memcpy(op->oprom_array, prop->name, len);
 182         op->oprom_array[len] = '\0';
 183         op->oprom_size = ++len;
 184
 185         return copyout(argp, op, sizeof(int) + bufsize);
 186 }
 187
 188 static int opromsetopt(struct device_node *dp, struct openpromio *op, int bufsize)
 189 {
 190         char *buf = op->oprom_array + strlen(op->oprom_array) + 1;
 191         int len = op->oprom_array + bufsize - buf;
 192
 193         return of_set_property(options_node, op->oprom_array, buf, len);
 194 }
 195
 196 static int opromnext(void __user *argp, unsigned int cmd, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
 197 {
 198         phandle ph;
 199
 200         BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
 201
 202         if (bufsize < sizeof(phandle))
 203                 return -EINVAL;
 204
 205         ph = *((int *) op->oprom_array);
 206         if (ph) {
 207                 dp = of_find_node_by_phandle(ph);
 208                 if (!dp)
 209                         return -EINVAL;
 210
 211                 switch (cmd) {
 212                 case OPROMNEXT:
 213                         dp = dp->sibling;
 214                         break;
 215
 216                 case OPROMCHILD:
 217                         dp = dp->child;
 218                         break;
 219
 220                 case OPROMSETCUR:
 221                 default:
 222                         break;
 223                 };
 224         } else {
 225                 /* Sibling of node zero is the root node.  */
 226                 if (cmd != OPROMNEXT)
 227                         return -EINVAL;
 228
 229                 dp = of_find_node_by_path("/");
 230         }
 231
 232         ph = 0;
 233         if (dp)
 234                 ph = dp->node;
 235
 236         data->current_node = dp;
 237         *((int *) op->oprom_array) = ph;
 238         op->oprom_size = sizeof(phandle);
 239
 240         return copyout(argp, op, bufsize + sizeof(int));
 241 }
 242
 243 static int oprompci2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
 244 {
 245         int err = -EINVAL;
 246
 247         if (bufsize >= 2*sizeof(int)) {
 248 #ifdef CONFIG_PCI
 249                 struct pci_dev *pdev;
 250                 struct device_node *dp;
 251
 252                 pdev = pci_get_bus_and_slot (((int *) op->oprom_array)[0],
 253                                       ((int *) op->oprom_array)[1]);
 254
 255                 dp = pci_device_to_OF_node(pdev);
 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                 pci_dev_put(pdev);
 262 #endif
 263         }
 264
 265         return err;
 266 }
 267
 268 static int oprompath2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
 269 {
 270         phandle ph = 0;
 271
 272         dp = of_find_node_by_path(op->oprom_array);
 273         if (dp)
 274                 ph = dp->node;
 275         data->current_node = dp;
 276         *((int *)op->oprom_array) = ph;
 277         op->oprom_size = sizeof(int);
 278
 279         return copyout(argp, op, bufsize + sizeof(int));
 280 }
 281
 282 static int opromgetbootargs(void __user *argp, struct openpromio *op, int bufsize)
 283 {
 284         char *buf = saved_command_line;
 285         int len = strlen(buf);
 286
 287         if (len > bufsize)
 288                 return -EINVAL;
 289
 290         strcpy(op->oprom_array, buf);
 291         op->oprom_size = len;
 292
 293         return copyout(argp, op, bufsize + sizeof(int));
 294 }
 295
 296 /*
 297  *      SunOS and Solaris /dev/openprom ioctl calls.
 298  */
 299 static int openprom_sunos_ioctl(struct inode * inode, struct file * file,
 300                                 unsigned int cmd, unsigned long arg,
 301                                 struct device_node *dp)
 302 {
 303         DATA *data = file->private_data;
 304         struct openpromio *opp;
 305         int bufsize, error = 0;
 306         static int cnt;
 307         void __user *argp = (void __user *)arg;
 308
 309         if (cmd == OPROMSETOPT)
 310                 bufsize = getstrings(argp, &opp);
 311         else
 312                 bufsize = copyin(argp, &opp);
 313
 314         if (bufsize < 0)
 315                 return bufsize;
 316
 317         switch (cmd) {
 318         case OPROMGETOPT:
 319         case OPROMGETPROP:
 320                 error = opromgetprop(argp, dp, opp, bufsize);
 321                 break;
 322
 323         case OPROMNXTOPT:
 324         case OPROMNXTPROP:
 325                 error = opromnxtprop(argp, dp, opp, bufsize);
 326                 break;
 327
 328         case OPROMSETOPT:
 329         case OPROMSETOPT2:
 330                 error = opromsetopt(dp, opp, bufsize);
 331                 break;
 332
 333         case OPROMNEXT:
 334         case OPROMCHILD:
 335         case OPROMSETCUR:
 336                 error = opromnext(argp, cmd, dp, opp, bufsize, data);
 337                 break;
 338
 339         case OPROMPCI2NODE:
 340                 error = oprompci2node(argp, dp, opp, bufsize, data);
 341                 break;
 342
 343         case OPROMPATH2NODE:
 344                 error = oprompath2node(argp, dp, opp, bufsize, data);
 345                 break;
 346
 347         case OPROMGETBOOTARGS:
 348                 error = opromgetbootargs(argp, opp, bufsize);
 349                 break;
 350
 351         case OPROMU2P:
 352         case OPROMGETCONS:
 353         case OPROMGETFBNAME:
 354                 if (cnt++ < 10)
 355                         printk(KERN_INFO "openprom_sunos_ioctl: unimplemented ioctl\n");
 356                 error = -EINVAL;
 357                 break;
 358         default:
 359                 if (cnt++ < 10)
 360                         printk(KERN_INFO "openprom_sunos_ioctl: cmd 0x%X, arg 0x%lX\n", cmd, arg);
 361                 error = -EINVAL;
 362                 break;
 363         }
 364
 365         kfree(opp);
 366         return error;
 367 }
 368
 369 static struct device_node *get_node(phandle n, DATA *data)
 370 {
 371         struct device_node *dp = of_find_node_by_phandle(n);
 372
 373         if (dp)
 374                 data->lastnode = dp;
 375
 376         return dp;
 377 }
 378
 379 /* Copy in a whole string from userspace into kernelspace. */
 380 static int copyin_string(char __user *user, size_t len, char **ptr)
 381 {
 382         char *tmp;
 383
 384         if ((ssize_t)len < 0 || (ssize_t)(len + 1) < 0)
 385                 return -EINVAL;
 386
 387         tmp = kmalloc(len + 1, GFP_KERNEL);
 388         if (!tmp)
 389                 return -ENOMEM;
 390
 391         if (copy_from_user(tmp, user, len)) {
 392                 kfree(tmp);
 393                 return -EFAULT;
 394         }
 395
 396         tmp[len] = '\0';
 397
 398         *ptr = tmp;
 399
 400         return 0;
 401 }
 402
 403 /*
 404  *      NetBSD /dev/openprom ioctl calls.
 405  */
 406 static int opiocget(void __user *argp, DATA *data)
 407 {
 408         struct opiocdesc op;
 409         struct device_node *dp;
 410         char *str;
 411         const void *pval;
 412         int err, len;
 413
 414         if (copy_from_user(&op, argp, sizeof(op)))
 415                 return -EFAULT;
 416
 417         dp = get_node(op.op_nodeid, data);
 418
 419         err = copyin_string(op.op_name, op.op_namelen, &str);
 420         if (err)
 421                 return err;
 422
 423         pval = of_get_property(dp, str, &len);
 424         err = 0;
 425         if (!pval || len > op.op_buflen) {
 426                 err = -EINVAL;
 427         } else {
 428                 op.op_buflen = len;
 429                 if (copy_to_user(argp, &op, sizeof(op)) ||
 430                     copy_to_user(op.op_buf, pval, len))
 431                         err = -EFAULT;
 432         }
 433         kfree(str);
 434
 435         return err;
 436 }
 437
 438 static int opiocnextprop(void __user *argp, DATA *data)
 439 {
 440         struct opiocdesc op;
 441         struct device_node *dp;
 442         struct property *prop;
 443         char *str;
 444         int err, len;
 445
 446         if (copy_from_user(&op, argp, sizeof(op)))
 447                 return -EFAULT;
 448
 449         dp = get_node(op.op_nodeid, data);
 450         if (!dp)
 451                 return -EINVAL;
 452
 453         err = copyin_string(op.op_name, op.op_namelen, &str);
 454         if (err)
 455                 return err;
 456
 457         if (str[0] == '\0') {
 458                 prop = dp->properties;
 459         } else {
 460                 prop = of_find_property(dp, str, NULL);
 461                 if (prop)
 462                         prop = prop->next;
 463         }
 464         kfree(str);
 465
 466         if (!prop)
 467                 len = 0;
 468         else
 469                 len = prop->length;
 470
 471         if (len > op.op_buflen)
 472                 len = op.op_buflen;
 473
 474         if (copy_to_user(argp, &op, sizeof(op)))
 475                 return -EFAULT;
 476
 477         if (len &&
 478             copy_to_user(op.op_buf, prop->value, len))
 479                 return -EFAULT;
 480
 481         return 0;
 482 }
 483
 484 static int opiocset(void __user *argp, DATA *data)
 485 {
 486         struct opiocdesc op;
 487         struct device_node *dp;
 488         char *str, *tmp;
 489         int err;
 490
 491         if (copy_from_user(&op, argp, sizeof(op)))
 492                 return -EFAULT;
 493
 494         dp = get_node(op.op_nodeid, data);
 495         if (!dp)
 496                 return -EINVAL;
 497
 498         err = copyin_string(op.op_name, op.op_namelen, &str);
 499         if (err)
 500                 return err;
 501
 502         err = copyin_string(op.op_buf, op.op_buflen, &tmp);
 503         if (err) {
 504                 kfree(str);
 505                 return err;
 506         }
 507
 508         err = of_set_property(dp, str, tmp, op.op_buflen);
 509
 510         kfree(str);
 511         kfree(tmp);
 512
 513         return err;
 514 }
 515
 516 static int opiocgetnext(unsigned int cmd, void __user *argp)
 517 {
 518         struct device_node *dp;
 519         phandle nd;
 520
 521         BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
 522
 523         if (copy_from_user(&nd, argp, sizeof(phandle)))
 524                 return -EFAULT;
 525
 526         if (nd == 0) {
 527                 if (cmd != OPIOCGETNEXT)
 528                         return -EINVAL;
 529                 dp = of_find_node_by_path("/");
 530         } else {
 531                 dp = of_find_node_by_phandle(nd);
 532                 nd = 0;
 533                 if (dp) {
 534                         if (cmd == OPIOCGETNEXT)
 535                                 dp = dp->sibling;
 536                         else
 537                                 dp = dp->child;
 538                 }
 539         }
 540         if (dp)
 541                 nd = dp->node;
 542         if (copy_to_user(argp, &nd, sizeof(phandle)))
 543                 return -EFAULT;
 544
 545         return 0;
 546 }
 547
 548 static int openprom_bsd_ioctl(struct inode * inode, struct file * file,
 549                               unsigned int cmd, unsigned long arg)
 550 {
 551         DATA *data = (DATA *) file->private_data;
 552         void __user *argp = (void __user *)arg;
 553         int err;
 554
 555         switch (cmd) {
 556         case OPIOCGET:
 557                 err = opiocget(argp, data);
 558                 break;
 559
 560         case OPIOCNEXTPROP:
 561                 err = opiocnextprop(argp, data);
 562                 break;
 563
 564         case OPIOCSET:
 565                 err = opiocset(argp, data);
 566                 break;
 567
 568         case OPIOCGETOPTNODE:
 569                 BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
 570
 571                 if (copy_to_user(argp, &options_node->node, sizeof(phandle)))
 572                         return -EFAULT;
 573
 574                 return 0;
 575
 576         case OPIOCGETNEXT:
 577         case OPIOCGETCHILD:
 578                 err = opiocgetnext(cmd, argp);
 579                 break;
 580
 581         default:
 582                 return -EINVAL;
 583
 584         };
 585
 586         return err;
 587 }
 588
 589
 590 /*
 591  *      Handoff control to the correct ioctl handler.
 592  */
 593 static int openprom_ioctl(struct inode * inode, struct file * file,
 594                           unsigned int cmd, unsigned long arg)
 595 {
 596         DATA *data = (DATA *) file->private_data;
 597
 598         switch (cmd) {
 599         case OPROMGETOPT:
 600         case OPROMNXTOPT:
 601                 if ((file->f_mode & FMODE_READ) == 0)
 602                         return -EPERM;
 603                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 604                                             options_node);
 605
 606         case OPROMSETOPT:
 607         case OPROMSETOPT2:
 608                 if ((file->f_mode & FMODE_WRITE) == 0)
 609                         return -EPERM;
 610                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 611                                             options_node);
 612
 613         case OPROMNEXT:
 614         case OPROMCHILD:
 615         case OPROMGETPROP:
 616         case OPROMNXTPROP:
 617                 if ((file->f_mode & FMODE_READ) == 0)
 618                         return -EPERM;
 619                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 620                                             data->current_node);
 621
 622         case OPROMU2P:
 623         case OPROMGETCONS:
 624         case OPROMGETFBNAME:
 625         case OPROMGETBOOTARGS:
 626         case OPROMSETCUR:
 627         case OPROMPCI2NODE:
 628         case OPROMPATH2NODE:
 629                 if ((file->f_mode & FMODE_READ) == 0)
 630                         return -EPERM;
 631                 return openprom_sunos_ioctl(inode, file, cmd, arg, NULL);
 632
 633         case OPIOCGET:
 634         case OPIOCNEXTPROP:
 635         case OPIOCGETOPTNODE:
 636         case OPIOCGETNEXT:
 637         case OPIOCGETCHILD:
 638                 if ((file->f_mode & FMODE_READ) == 0)
 639                         return -EBADF;
 640                 return openprom_bsd_ioctl(inode,file,cmd,arg);
 641
 642         case OPIOCSET:
 643                 if ((file->f_mode & FMODE_WRITE) == 0)
 644                         return -EBADF;
 645                 return openprom_bsd_ioctl(inode,file,cmd,arg);
 646
 647         default:
 648                 return -EINVAL;
 649         };
 650 }
 651
 652 static long openprom_compat_ioctl(struct file *file, unsigned int cmd,
 653                 unsigned long arg)
 654 {
 655         long rval = -ENOTTY;
 656
 657         /*
 658          * SunOS/Solaris only, the NetBSD one's have embedded pointers in
 659          * the arg which we'd need to clean up...
 660          */
 661         switch (cmd) {
 662         case OPROMGETOPT:
 663         case OPROMSETOPT:
 664         case OPROMNXTOPT:
 665         case OPROMSETOPT2:
 666         case OPROMNEXT:
 667         case OPROMCHILD:
 668         case OPROMGETPROP:
 669         case OPROMNXTPROP:
 670         case OPROMU2P:
 671         case OPROMGETCONS:
 672         case OPROMGETFBNAME:
 673         case OPROMGETBOOTARGS:
 674         case OPROMSETCUR:
 675         case OPROMPCI2NODE:
 676         case OPROMPATH2NODE:
 677                 rval = openprom_ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
 678                 break;
 679         }
 680
 681         return rval;
 682 }
 683
 684 static int openprom_open(struct inode * inode, struct file * file)
 685 {
 686         DATA *data;
 687
 688         data = kmalloc(sizeof(DATA), GFP_KERNEL);
 689         if (!data)
 690                 return -ENOMEM;
 691
 692         data->current_node = of_find_node_by_path("/");
 693         data->lastnode = data->current_node;
 694         file->private_data = (void *) data;
 695
 696         return 0;
 697 }
 698
 699 static int openprom_release(struct inode * inode, struct file * file)
 700 {
 701         kfree(file->private_data);
 702         return 0;
 703 }
 704
 705 static const struct file_operations openprom_fops = {
 706         .owner =        THIS_MODULE,
 707         .llseek =       no_llseek,
 708         .ioctl =        openprom_ioctl,
 709         .compat_ioctl = openprom_compat_ioctl,
 710         .open =         openprom_open,
 711         .release =      openprom_release,
 712 };
 713
 714 static struct miscdevice openprom_dev = {
 715         .minor          = SUN_OPENPROM_MINOR,
 716         .name           = "openprom",
 717         .fops           = &openprom_fops,
 718 };
 719
 720 static int __init openprom_init(void)
 721 {
 722         struct device_node *dp;
 723         int err;
 724
 725         err = misc_register(&openprom_dev);
 726         if (err)
 727                 return err;
 728
 729         dp = of_find_node_by_path("/");
 730         dp = dp->child;
 731         while (dp) {
 732                 if (!strcmp(dp->name, "options"))
 733                         break;
 734                 dp = dp->sibling;
 735         }
 736         options_node = dp;
 737
 738         if (!options_node) {
 739                 misc_deregister(&openprom_dev);
 740                 return -EIO;
 741         }
 742
 743         return 0;
 744 }
 745
 746 static void __exit openprom_cleanup(void)
 747 {
 748         misc_deregister(&openprom_dev);
 749 }
 750
 751 module_init(openprom_init);
 752 module_exit(openprom_cleanup);