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