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/config.h>
  33 #include <linux/module.h>
  34 #include <linux/kernel.h>
  35 #include <linux/sched.h>
  36 #include <linux/errno.h>
  37 #include <linux/slab.h>
  38 #include <linux/string.h>
  39 #include <linux/miscdevice.h>
  40 #include <linux/init.h>
  41 #include <linux/fs.h>
  42 #include <asm/oplib.h>
  43 #include <asm/prom.h>
  44 #include <asm/system.h>
  45 #include <asm/uaccess.h>
  46 #include <asm/openpromio.h>
  47 #ifdef CONFIG_PCI
  48 #include <linux/pci.h>
  49 #include <asm/pbm.h>
  50 #endif
  51
  52 MODULE_AUTHOR("Thomas K. Dyas (tdyas@noc.rutgers.edu) and Eddie C. Dost  (ecd@skynet.be)");
  53 MODULE_DESCRIPTION("OPENPROM Configuration Driver");
  54 MODULE_LICENSE("GPL");
  55 MODULE_VERSION("1.0");
  56
  57 /* Private data kept by the driver for each descriptor. */
  58 typedef struct openprom_private_data
  59 {
  60         struct device_node *current_node; /* Current node for SunOS ioctls. */
  61         struct device_node *lastnode; /* Last valid node used by BSD ioctls. */
  62 } DATA;
  63
  64 /* ID of the PROM node containing all of the EEPROM options. */
  65 static struct device_node *options_node;
  66
  67 /*
  68  * Copy an openpromio structure into kernel space from user space.
  69  * This routine does error checking to make sure that all memory
  70  * accesses are within bounds. A pointer to the allocated openpromio
  71  * structure will be placed in "*opp_p". Return value is the length
  72  * of the user supplied buffer.
  73  */
  74 static int copyin(struct openpromio __user *info, struct openpromio **opp_p)
  75 {
  76         unsigned int bufsize;
  77
  78         if (!info || !opp_p)
  79                 return -EFAULT;
  80
  81         if (get_user(bufsize, &info->oprom_size))
  82                 return -EFAULT;
  83
  84         if (bufsize == 0)
  85                 return -EINVAL;
  86
  87         /* If the bufsize is too large, just limit it.
  88          * Fix from Jason Rappleye.
  89          */
  90         if (bufsize > OPROMMAXPARAM)
  91                 bufsize = OPROMMAXPARAM;
  92
  93         if (!(*opp_p = kzalloc(sizeof(int) + bufsize + 1, GFP_KERNEL)))
  94                 return -ENOMEM;
  95
  96         if (copy_from_user(&(*opp_p)->oprom_array,
  97                            &info->oprom_array, bufsize)) {
  98                 kfree(*opp_p);
  99                 return -EFAULT;
 100         }
 101         return bufsize;
 102 }
 103
 104 static int getstrings(struct openpromio __user *info, struct openpromio **opp_p)
 105 {
 106         int n, bufsize;
 107         char c;
 108
 109         if (!info || !opp_p)
 110                 return -EFAULT;
 111
 112         if (!(*opp_p = kzalloc(sizeof(int) + OPROMMAXPARAM + 1, GFP_KERNEL)))
 113                 return -ENOMEM;
 114
 115         (*opp_p)->oprom_size = 0;
 116
 117         n = bufsize = 0;
 118         while ((n < 2) && (bufsize < OPROMMAXPARAM)) {
 119                 if (get_user(c, &info->oprom_array[bufsize])) {
 120                         kfree(*opp_p);
 121                         return -EFAULT;
 122                 }
 123                 if (c == '\0')
 124                         n++;
 125                 (*opp_p)->oprom_array[bufsize++] = c;
 126         }
 127         if (!n) {
 128                 kfree(*opp_p);
 129                 return -EINVAL;
 130         }
 131         return bufsize;
 132 }
 133
 134 /*
 135  * Copy an openpromio structure in kernel space back to user space.
 136  */
 137 static int copyout(void __user *info, struct openpromio *opp, int len)
 138 {
 139         if (copy_to_user(info, opp, len))
 140                 return -EFAULT;
 141         return 0;
 142 }
 143
 144 static int opromgetprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize)
 145 {
 146         void *pval;
 147         int len;
 148
 149         pval = of_get_property(dp, op->oprom_array, &len);
 150         if (!pval || len <= 0 || len > bufsize)
 151                 return copyout(argp, op, sizeof(int));
 152
 153         memcpy(op->oprom_array, pval, len);
 154         op->oprom_array[len] = '\0';
 155         op->oprom_size = len;
 156
 157         return copyout(argp, op, sizeof(int) + bufsize);
 158 }
 159
 160 static int opromnxtprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize)
 161 {
 162         struct property *prop;
 163         int len;
 164
 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 pcidev_cookie *pcp;
 251                 pdev = pci_find_slot (((int *) op->oprom_array)[0],
 252                                       ((int *) op->oprom_array)[1]);
 253
 254                 pcp = pdev->sysdata;
 255                 if (pcp != NULL) {
 256                         dp = pcp->prom_node;
 257                         data->current_node = dp;
 258                         *((int *)op->oprom_array) = dp->node;
 259                         op->oprom_size = sizeof(int);
 260                         err = copyout(argp, op, bufsize + sizeof(int));
 261                 }
 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         dp = of_find_node_by_path(op->oprom_array);
 271         data->current_node = dp;
 272         *((int *)op->oprom_array) = dp->node;
 273         op->oprom_size = sizeof(int);
 274
 275         return copyout(argp, op, bufsize + sizeof(int));
 276 }
 277
 278 static int opromgetbootargs(void __user *argp, struct openpromio *op, int bufsize)
 279 {
 280         char *buf = saved_command_line;
 281         int len = strlen(buf);
 282
 283         if (len > bufsize)
 284                 return -EINVAL;
 285
 286         strcpy(op->oprom_array, buf);
 287         op->oprom_size = len;
 288
 289         return copyout(argp, op, bufsize + sizeof(int));
 290 }
 291
 292 /*
 293  *      SunOS and Solaris /dev/openprom ioctl calls.
 294  */
 295 static int openprom_sunos_ioctl(struct inode * inode, struct file * file,
 296                                 unsigned int cmd, unsigned long arg,
 297                                 struct device_node *dp)
 298 {
 299         DATA *data = file->private_data;
 300         struct openpromio *opp;
 301         int bufsize, error = 0;
 302         static int cnt;
 303         void __user *argp = (void __user *)arg;
 304
 305         if (cmd == OPROMSETOPT)
 306                 bufsize = getstrings(argp, &opp);
 307         else
 308                 bufsize = copyin(argp, &opp);
 309
 310         if (bufsize < 0)
 311                 return bufsize;
 312
 313         switch (cmd) {
 314         case OPROMGETOPT:
 315         case OPROMGETPROP:
 316                 error = opromgetprop(argp, dp, opp, bufsize);
 317                 break;
 318
 319         case OPROMNXTOPT:
 320         case OPROMNXTPROP:
 321                 error = opromnxtprop(argp, dp, opp, bufsize);
 322                 break;
 323
 324         case OPROMSETOPT:
 325         case OPROMSETOPT2:
 326                 error = opromsetopt(dp, opp, bufsize);
 327                 break;
 328
 329         case OPROMNEXT:
 330         case OPROMCHILD:
 331         case OPROMSETCUR:
 332                 error = opromnext(argp, cmd, dp, opp, bufsize, data);
 333                 break;
 334
 335         case OPROMPCI2NODE:
 336                 error = oprompci2node(argp, dp, opp, bufsize, data);
 337                 break;
 338
 339         case OPROMPATH2NODE:
 340                 error = oprompath2node(argp, dp, opp, bufsize, data);
 341                 break;
 342
 343         case OPROMGETBOOTARGS:
 344                 error = opromgetbootargs(argp, opp, bufsize);
 345                 break;
 346
 347         case OPROMU2P:
 348         case OPROMGETCONS:
 349         case OPROMGETFBNAME:
 350                 if (cnt++ < 10)
 351                         printk(KERN_INFO "openprom_sunos_ioctl: unimplemented ioctl\n");
 352                 error = -EINVAL;
 353                 break;
 354         default:
 355                 if (cnt++ < 10)
 356                         printk(KERN_INFO "openprom_sunos_ioctl: cmd 0x%X, arg 0x%lX\n", cmd, arg);
 357                 error = -EINVAL;
 358                 break;
 359         }
 360
 361         kfree(opp);
 362         return error;
 363 }
 364
 365 static struct device_node *get_node(phandle n, DATA *data)
 366 {
 367         struct device_node *dp = of_find_node_by_phandle(n);
 368
 369         if (dp)
 370                 data->lastnode = dp;
 371
 372         return dp;
 373 }
 374
 375 /* Copy in a whole string from userspace into kernelspace. */
 376 static int copyin_string(char __user *user, size_t len, char **ptr)
 377 {
 378         char *tmp;
 379
 380         if ((ssize_t)len < 0 || (ssize_t)(len + 1) < 0)
 381                 return -EINVAL;
 382
 383         tmp = kmalloc(len + 1, GFP_KERNEL);
 384         if (!tmp)
 385                 return -ENOMEM;
 386
 387         if (copy_from_user(tmp, user, len)) {
 388                 kfree(tmp);
 389                 return -EFAULT;
 390         }
 391
 392         tmp[len] = '\0';
 393
 394         *ptr = tmp;
 395
 396         return 0;
 397 }
 398
 399 /*
 400  *      NetBSD /dev/openprom ioctl calls.
 401  */
 402 static int opiocget(void __user *argp, DATA *data)
 403 {
 404         struct opiocdesc op;
 405         struct device_node *dp;
 406         char *str;
 407         void *pval;
 408         int err, len;
 409
 410         if (copy_from_user(&op, argp, sizeof(op)))
 411                 return -EFAULT;
 412
 413         dp = get_node(op.op_nodeid, data);
 414
 415         err = copyin_string(op.op_name, op.op_namelen, &str);
 416         if (err)
 417                 return err;
 418
 419         pval = of_get_property(dp, str, &len);
 420         err = 0;
 421         if (!pval || len > op.op_buflen) {
 422                 err = -EINVAL;
 423         } else {
 424                 op.op_buflen = len;
 425                 if (copy_to_user(argp, &op, sizeof(op)) ||
 426                     copy_to_user(op.op_buf, pval, len))
 427                         err = -EFAULT;
 428         }
 429         kfree(str);
 430
 431         return err;
 432 }
 433
 434 static int opiocnextprop(void __user *argp, DATA *data)
 435 {
 436         struct opiocdesc op;
 437         struct device_node *dp;
 438         struct property *prop;
 439         char *str;
 440         int err, len;
 441
 442         if (copy_from_user(&op, argp, sizeof(op)))
 443                 return -EFAULT;
 444
 445         dp = get_node(op.op_nodeid, data);
 446         if (!dp)
 447                 return -EINVAL;
 448
 449         err = copyin_string(op.op_name, op.op_namelen, &str);
 450         if (err)
 451                 return err;
 452
 453         if (str[0] == '\0') {
 454                 prop = dp->properties;
 455         } else {
 456                 prop = of_find_property(dp, str, NULL);
 457                 if (prop)
 458                         prop = prop->next;
 459         }
 460         kfree(str);
 461
 462         if (!prop)
 463                 len = 0;
 464         else
 465                 len = prop->length;
 466
 467         if (len > op.op_buflen)
 468                 len = op.op_buflen;
 469
 470         if (copy_to_user(argp, &op, sizeof(op)))
 471                 return -EFAULT;
 472
 473         if (len &&
 474             copy_to_user(op.op_buf, prop->value, len))
 475                 return -EFAULT;
 476
 477         return 0;
 478 }
 479
 480 static int opiocset(void __user *argp, DATA *data)
 481 {
 482         struct opiocdesc op;
 483         struct device_node *dp;
 484         char *str, *tmp;
 485         int err;
 486
 487         if (copy_from_user(&op, argp, sizeof(op)))
 488                 return -EFAULT;
 489
 490         dp = get_node(op.op_nodeid, data);
 491         if (!dp)
 492                 return -EINVAL;
 493
 494         err = copyin_string(op.op_name, op.op_namelen, &str);
 495         if (err)
 496                 return err;
 497
 498         err = copyin_string(op.op_buf, op.op_buflen, &tmp);
 499         if (err) {
 500                 kfree(str);
 501                 return err;
 502         }
 503
 504         err = of_set_property(dp, str, tmp, op.op_buflen);
 505
 506         kfree(str);
 507         kfree(tmp);
 508
 509         return err;
 510 }
 511
 512 static int opiocgetnext(unsigned int cmd, void __user *argp)
 513 {
 514         struct device_node *dp;
 515         phandle nd;
 516
 517         BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
 518
 519         if (copy_from_user(&nd, argp, sizeof(phandle)))
 520                 return -EFAULT;
 521
 522         if (nd == 0) {
 523                 if (cmd != OPIOCGETNEXT)
 524                         return -EINVAL;
 525                 dp = of_find_node_by_path("/");
 526         } else {
 527                 dp = of_find_node_by_phandle(nd);
 528                 nd = 0;
 529                 if (dp) {
 530                         if (cmd == OPIOCGETNEXT)
 531                                 dp = dp->sibling;
 532                         else
 533                                 dp = dp->child;
 534                 }
 535         }
 536         if (dp)
 537                 nd = dp->node;
 538         if (copy_to_user(argp, &nd, sizeof(phandle)))
 539                 return -EFAULT;
 540
 541         return 0;
 542 }
 543
 544 static int openprom_bsd_ioctl(struct inode * inode, struct file * file,
 545                               unsigned int cmd, unsigned long arg)
 546 {
 547         DATA *data = (DATA *) file->private_data;
 548         void __user *argp = (void __user *)arg;
 549         int err;
 550
 551         switch (cmd) {
 552         case OPIOCGET:
 553                 err = opiocget(argp, data);
 554                 break;
 555
 556         case OPIOCNEXTPROP:
 557                 err = opiocnextprop(argp, data);
 558                 break;
 559
 560         case OPIOCSET:
 561                 err = opiocset(argp, data);
 562                 break;
 563
 564         case OPIOCGETOPTNODE:
 565                 BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
 566
 567                 if (copy_to_user(argp, &options_node->node, sizeof(phandle)))
 568                         return -EFAULT;
 569
 570                 return 0;
 571
 572         case OPIOCGETNEXT:
 573         case OPIOCGETCHILD:
 574                 err = opiocgetnext(cmd, argp);
 575                 break;
 576
 577         default:
 578                 return -EINVAL;
 579
 580         };
 581
 582         return err;
 583 }
 584
 585
 586 /*
 587  *      Handoff control to the correct ioctl handler.
 588  */
 589 static int openprom_ioctl(struct inode * inode, struct file * file,
 590                           unsigned int cmd, unsigned long arg)
 591 {
 592         DATA *data = (DATA *) file->private_data;
 593
 594         switch (cmd) {
 595         case OPROMGETOPT:
 596         case OPROMNXTOPT:
 597                 if ((file->f_mode & FMODE_READ) == 0)
 598                         return -EPERM;
 599                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 600                                             options_node);
 601
 602         case OPROMSETOPT:
 603         case OPROMSETOPT2:
 604                 if ((file->f_mode & FMODE_WRITE) == 0)
 605                         return -EPERM;
 606                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 607                                             options_node);
 608
 609         case OPROMNEXT:
 610         case OPROMCHILD:
 611         case OPROMGETPROP:
 612         case OPROMNXTPROP:
 613                 if ((file->f_mode & FMODE_READ) == 0)
 614                         return -EPERM;
 615                 return openprom_sunos_ioctl(inode, file, cmd, arg,
 616                                             data->current_node);
 617
 618         case OPROMU2P:
 619         case OPROMGETCONS:
 620         case OPROMGETFBNAME:
 621         case OPROMGETBOOTARGS:
 622         case OPROMSETCUR:
 623         case OPROMPCI2NODE:
 624         case OPROMPATH2NODE:
 625                 if ((file->f_mode & FMODE_READ) == 0)
 626                         return -EPERM;
 627                 return openprom_sunos_ioctl(inode, file, cmd, arg, 0);
 628
 629         case OPIOCGET:
 630         case OPIOCNEXTPROP:
 631         case OPIOCGETOPTNODE:
 632         case OPIOCGETNEXT:
 633         case OPIOCGETCHILD:
 634                 if ((file->f_mode & FMODE_READ) == 0)
 635                         return -EBADF;
 636                 return openprom_bsd_ioctl(inode,file,cmd,arg);
 637
 638         case OPIOCSET:
 639                 if ((file->f_mode & FMODE_WRITE) == 0)
 640                         return -EBADF;
 641                 return openprom_bsd_ioctl(inode,file,cmd,arg);
 642
 643         default:
 644                 return -EINVAL;
 645         };
 646 }
 647
 648 static long openprom_compat_ioctl(struct file *file, unsigned int cmd,
 649                 unsigned long arg)
 650 {
 651         long rval = -ENOTTY;
 652
 653         /*
 654          * SunOS/Solaris only, the NetBSD one's have embedded pointers in
 655          * the arg which we'd need to clean up...
 656          */
 657         switch (cmd) {
 658         case OPROMGETOPT:
 659         case OPROMSETOPT:
 660         case OPROMNXTOPT:
 661         case OPROMSETOPT2:
 662         case OPROMNEXT:
 663         case OPROMCHILD:
 664         case OPROMGETPROP:
 665         case OPROMNXTPROP:
 666         case OPROMU2P:
 667         case OPROMGETCONS:
 668         case OPROMGETFBNAME:
 669         case OPROMGETBOOTARGS:
 670         case OPROMSETCUR:
 671         case OPROMPCI2NODE:
 672         case OPROMPATH2NODE:
 673                 rval = openprom_ioctl(file->f_dentry->d_inode, file, cmd, arg);
 674                 break;
 675         }
 676
 677         return rval;
 678 }
 679
 680 static int openprom_open(struct inode * inode, struct file * file)
 681 {
 682         DATA *data;
 683
 684         data = kmalloc(sizeof(DATA), GFP_KERNEL);
 685         if (!data)
 686                 return -ENOMEM;
 687
 688         data->current_node = of_find_node_by_path("/");
 689         data->lastnode = data->current_node;
 690         file->private_data = (void *) data;
 691
 692         return 0;
 693 }
 694
 695 static int openprom_release(struct inode * inode, struct file * file)
 696 {
 697         kfree(file->private_data);
 698         return 0;
 699 }
 700
 701 static struct file_operations openprom_fops = {
 702         .owner =        THIS_MODULE,
 703         .llseek =       no_llseek,
 704         .ioctl =        openprom_ioctl,
 705         .compat_ioctl = openprom_compat_ioctl,
 706         .open =         openprom_open,
 707         .release =      openprom_release,
 708 };
 709
 710 static struct miscdevice openprom_dev = {
 711         .minor          = SUN_OPENPROM_MINOR,
 712         .name           = "openprom",
 713         .fops           = &openprom_fops,
 714 };
 715
 716 static int __init openprom_init(void)
 717 {
 718         struct device_node *dp;
 719         int err;
 720
 721         err = misc_register(&openprom_dev);
 722         if (err)
 723                 return err;
 724
 725         dp = of_find_node_by_path("/");
 726         dp = dp->child;
 727         while (dp) {
 728                 if (!strcmp(dp->name, "options"))
 729                         break;
 730                 dp = dp->sibling;
 731         }
 732         options_node = dp;
 733
 734         if (!options_node) {
 735                 misc_deregister(&openprom_dev);
 736                 return -EIO;
 737         }
 738
 739         return 0;
 740 }
 741
 742 static void __exit openprom_cleanup(void)
 743 {
 744         misc_deregister(&openprom_dev);
 745 }
 746
 747 module_init(openprom_init);
 748 module_exit(openprom_cleanup);