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/mutex.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 #endif
49
50 MODULE_AUTHOR("Thomas K. Dyas (tdyas@noc.rutgers.edu) and Eddie C. Dost (ecd@skynet.be)");
51 MODULE_DESCRIPTION("OPENPROM Configuration Driver");
52 MODULE_LICENSE("GPL");
53 MODULE_VERSION("1.0");
54 MODULE_ALIAS_MISCDEV(SUN_OPENPROM_MINOR);
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 DEFINE_MUTEX(openprom_mutex);
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 */
copyin(struct openpromio __user * info,struct openpromio ** opp_p)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
getstrings(struct openpromio __user * info,struct openpromio ** opp_p)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 */
copyout(void __user * info,struct openpromio * opp,int len)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
opromgetprop(void __user * argp,struct device_node * dp,struct openpromio * op,int bufsize)144 static int opromgetprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize)
145 {
146 const void *pval;
147 int len;
148
149 if (!dp ||
150 !(pval = of_get_property(dp, op->oprom_array, &len)) ||
151 len <= 0 || len > bufsize)
152 return copyout(argp, op, sizeof(int));
153
154 memcpy(op->oprom_array, pval, len);
155 op->oprom_array[len] = '\0';
156 op->oprom_size = len;
157
158 return copyout(argp, op, sizeof(int) + bufsize);
159 }
160
opromnxtprop(void __user * argp,struct device_node * dp,struct openpromio * op,int bufsize)161 static int opromnxtprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize)
162 {
163 struct property *prop;
164 int len;
165
166 if (!dp)
167 return copyout(argp, op, sizeof(int));
168 if (op->oprom_array[0] == '\0') {
169 prop = dp->properties;
170 if (!prop)
171 return copyout(argp, op, sizeof(int));
172 len = strlen(prop->name);
173 } else {
174 prop = of_find_property(dp, op->oprom_array, NULL);
175
176 if (!prop ||
177 !prop->next ||
178 (len = strlen(prop->next->name)) + 1 > bufsize)
179 return copyout(argp, op, sizeof(int));
180
181 prop = prop->next;
182 }
183
184 memcpy(op->oprom_array, prop->name, len);
185 op->oprom_array[len] = '\0';
186 op->oprom_size = ++len;
187
188 return copyout(argp, op, sizeof(int) + bufsize);
189 }
190
opromsetopt(struct device_node * dp,struct openpromio * op,int bufsize)191 static int opromsetopt(struct device_node *dp, struct openpromio *op, int bufsize)
192 {
193 char *buf = op->oprom_array + strlen(op->oprom_array) + 1;
194 int len = op->oprom_array + bufsize - buf;
195
196 return of_set_property(options_node, op->oprom_array, buf, len);
197 }
198
opromnext(void __user * argp,unsigned int cmd,struct device_node * dp,struct openpromio * op,int bufsize,DATA * data)199 static int opromnext(void __user *argp, unsigned int cmd, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
200 {
201 phandle ph;
202
203 BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
204
205 if (bufsize < sizeof(phandle))
206 return -EINVAL;
207
208 ph = *((int *) op->oprom_array);
209 if (ph) {
210 dp = of_find_node_by_phandle(ph);
211 if (!dp)
212 return -EINVAL;
213
214 switch (cmd) {
215 case OPROMNEXT:
216 dp = dp->sibling;
217 break;
218
219 case OPROMCHILD:
220 dp = dp->child;
221 break;
222
223 case OPROMSETCUR:
224 default:
225 break;
226 };
227 } else {
228 /* Sibling of node zero is the root node. */
229 if (cmd != OPROMNEXT)
230 return -EINVAL;
231
232 dp = of_find_node_by_path("/");
233 }
234
235 ph = 0;
236 if (dp)
237 ph = dp->phandle;
238
239 data->current_node = dp;
240 *((int *) op->oprom_array) = ph;
241 op->oprom_size = sizeof(phandle);
242
243 return copyout(argp, op, bufsize + sizeof(int));
244 }
245
oprompci2node(void __user * argp,struct device_node * dp,struct openpromio * op,int bufsize,DATA * data)246 static int oprompci2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
247 {
248 int err = -EINVAL;
249
250 if (bufsize >= 2*sizeof(int)) {
251 #ifdef CONFIG_PCI
252 struct pci_dev *pdev;
253 struct device_node *dp;
254
255 pdev = pci_get_bus_and_slot (((int *) op->oprom_array)[0],
256 ((int *) op->oprom_array)[1]);
257
258 dp = pci_device_to_OF_node(pdev);
259 data->current_node = dp;
260 *((int *)op->oprom_array) = dp->phandle;
261 op->oprom_size = sizeof(int);
262 err = copyout(argp, op, bufsize + sizeof(int));
263
264 pci_dev_put(pdev);
265 #endif
266 }
267
268 return err;
269 }
270
oprompath2node(void __user * argp,struct device_node * dp,struct openpromio * op,int bufsize,DATA * data)271 static int oprompath2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
272 {
273 phandle ph = 0;
274
275 dp = of_find_node_by_path(op->oprom_array);
276 if (dp)
277 ph = dp->phandle;
278 data->current_node = dp;
279 *((int *)op->oprom_array) = ph;
280 op->oprom_size = sizeof(int);
281
282 return copyout(argp, op, bufsize + sizeof(int));
283 }
284
opromgetbootargs(void __user * argp,struct openpromio * op,int bufsize)285 static int opromgetbootargs(void __user *argp, struct openpromio *op, int bufsize)
286 {
287 char *buf = saved_command_line;
288 int len = strlen(buf);
289
290 if (len > bufsize)
291 return -EINVAL;
292
293 strcpy(op->oprom_array, buf);
294 op->oprom_size = len;
295
296 return copyout(argp, op, bufsize + sizeof(int));
297 }
298
299 /*
300 * SunOS and Solaris /dev/openprom ioctl calls.
301 */
openprom_sunos_ioctl(struct file * file,unsigned int cmd,unsigned long arg,struct device_node * dp)302 static long openprom_sunos_ioctl(struct file * file,
303 unsigned int cmd, unsigned long arg,
304 struct device_node *dp)
305 {
306 DATA *data = file->private_data;
307 struct openpromio *opp = NULL;
308 int bufsize, error = 0;
309 static int cnt;
310 void __user *argp = (void __user *)arg;
311
312 if (cmd == OPROMSETOPT)
313 bufsize = getstrings(argp, &opp);
314 else
315 bufsize = copyin(argp, &opp);
316
317 if (bufsize < 0)
318 return bufsize;
319
320 mutex_lock(&openprom_mutex);
321
322 switch (cmd) {
323 case OPROMGETOPT:
324 case OPROMGETPROP:
325 error = opromgetprop(argp, dp, opp, bufsize);
326 break;
327
328 case OPROMNXTOPT:
329 case OPROMNXTPROP:
330 error = opromnxtprop(argp, dp, opp, bufsize);
331 break;
332
333 case OPROMSETOPT:
334 case OPROMSETOPT2:
335 error = opromsetopt(dp, opp, bufsize);
336 break;
337
338 case OPROMNEXT:
339 case OPROMCHILD:
340 case OPROMSETCUR:
341 error = opromnext(argp, cmd, dp, opp, bufsize, data);
342 break;
343
344 case OPROMPCI2NODE:
345 error = oprompci2node(argp, dp, opp, bufsize, data);
346 break;
347
348 case OPROMPATH2NODE:
349 error = oprompath2node(argp, dp, opp, bufsize, data);
350 break;
351
352 case OPROMGETBOOTARGS:
353 error = opromgetbootargs(argp, opp, bufsize);
354 break;
355
356 case OPROMU2P:
357 case OPROMGETCONS:
358 case OPROMGETFBNAME:
359 if (cnt++ < 10)
360 printk(KERN_INFO "openprom_sunos_ioctl: unimplemented ioctl\n");
361 error = -EINVAL;
362 break;
363 default:
364 if (cnt++ < 10)
365 printk(KERN_INFO "openprom_sunos_ioctl: cmd 0x%X, arg 0x%lX\n", cmd, arg);
366 error = -EINVAL;
367 break;
368 }
369
370 kfree(opp);
371 mutex_unlock(&openprom_mutex);
372
373 return error;
374 }
375
get_node(phandle n,DATA * data)376 static struct device_node *get_node(phandle n, DATA *data)
377 {
378 struct device_node *dp = of_find_node_by_phandle(n);
379
380 if (dp)
381 data->lastnode = dp;
382
383 return dp;
384 }
385
386 /* Copy in a whole string from userspace into kernelspace. */
copyin_string(char __user * user,size_t len,char ** ptr)387 static int copyin_string(char __user *user, size_t len, char **ptr)
388 {
389 char *tmp;
390
391 if ((ssize_t)len < 0 || (ssize_t)(len + 1) < 0)
392 return -EINVAL;
393
394 tmp = kmalloc(len + 1, GFP_KERNEL);
395 if (!tmp)
396 return -ENOMEM;
397
398 if (copy_from_user(tmp, user, len)) {
399 kfree(tmp);
400 return -EFAULT;
401 }
402
403 tmp[len] = '\0';
404
405 *ptr = tmp;
406
407 return 0;
408 }
409
410 /*
411 * NetBSD /dev/openprom ioctl calls.
412 */
opiocget(void __user * argp,DATA * data)413 static int opiocget(void __user *argp, DATA *data)
414 {
415 struct opiocdesc op;
416 struct device_node *dp;
417 char *str;
418 const void *pval;
419 int err, len;
420
421 if (copy_from_user(&op, argp, sizeof(op)))
422 return -EFAULT;
423
424 dp = get_node(op.op_nodeid, data);
425
426 err = copyin_string(op.op_name, op.op_namelen, &str);
427 if (err)
428 return err;
429
430 pval = of_get_property(dp, str, &len);
431 err = 0;
432 if (!pval || len > op.op_buflen) {
433 err = -EINVAL;
434 } else {
435 op.op_buflen = len;
436 if (copy_to_user(argp, &op, sizeof(op)) ||
437 copy_to_user(op.op_buf, pval, len))
438 err = -EFAULT;
439 }
440 kfree(str);
441
442 return err;
443 }
444
opiocnextprop(void __user * argp,DATA * data)445 static int opiocnextprop(void __user *argp, DATA *data)
446 {
447 struct opiocdesc op;
448 struct device_node *dp;
449 struct property *prop;
450 char *str;
451 int err, len;
452
453 if (copy_from_user(&op, argp, sizeof(op)))
454 return -EFAULT;
455
456 dp = get_node(op.op_nodeid, data);
457 if (!dp)
458 return -EINVAL;
459
460 err = copyin_string(op.op_name, op.op_namelen, &str);
461 if (err)
462 return err;
463
464 if (str[0] == '\0') {
465 prop = dp->properties;
466 } else {
467 prop = of_find_property(dp, str, NULL);
468 if (prop)
469 prop = prop->next;
470 }
471 kfree(str);
472
473 if (!prop)
474 len = 0;
475 else
476 len = prop->length;
477
478 if (len > op.op_buflen)
479 len = op.op_buflen;
480
481 if (copy_to_user(argp, &op, sizeof(op)))
482 return -EFAULT;
483
484 if (len &&
485 copy_to_user(op.op_buf, prop->value, len))
486 return -EFAULT;
487
488 return 0;
489 }
490
opiocset(void __user * argp,DATA * data)491 static int opiocset(void __user *argp, DATA *data)
492 {
493 struct opiocdesc op;
494 struct device_node *dp;
495 char *str, *tmp;
496 int err;
497
498 if (copy_from_user(&op, argp, sizeof(op)))
499 return -EFAULT;
500
501 dp = get_node(op.op_nodeid, data);
502 if (!dp)
503 return -EINVAL;
504
505 err = copyin_string(op.op_name, op.op_namelen, &str);
506 if (err)
507 return err;
508
509 err = copyin_string(op.op_buf, op.op_buflen, &tmp);
510 if (err) {
511 kfree(str);
512 return err;
513 }
514
515 err = of_set_property(dp, str, tmp, op.op_buflen);
516
517 kfree(str);
518 kfree(tmp);
519
520 return err;
521 }
522
opiocgetnext(unsigned int cmd,void __user * argp)523 static int opiocgetnext(unsigned int cmd, void __user *argp)
524 {
525 struct device_node *dp;
526 phandle nd;
527
528 BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
529
530 if (copy_from_user(&nd, argp, sizeof(phandle)))
531 return -EFAULT;
532
533 if (nd == 0) {
534 if (cmd != OPIOCGETNEXT)
535 return -EINVAL;
536 dp = of_find_node_by_path("/");
537 } else {
538 dp = of_find_node_by_phandle(nd);
539 nd = 0;
540 if (dp) {
541 if (cmd == OPIOCGETNEXT)
542 dp = dp->sibling;
543 else
544 dp = dp->child;
545 }
546 }
547 if (dp)
548 nd = dp->phandle;
549 if (copy_to_user(argp, &nd, sizeof(phandle)))
550 return -EFAULT;
551
552 return 0;
553 }
554
openprom_bsd_ioctl(struct file * file,unsigned int cmd,unsigned long arg)555 static int openprom_bsd_ioctl(struct file * file,
556 unsigned int cmd, unsigned long arg)
557 {
558 DATA *data = file->private_data;
559 void __user *argp = (void __user *)arg;
560 int err;
561
562 mutex_lock(&openprom_mutex);
563 switch (cmd) {
564 case OPIOCGET:
565 err = opiocget(argp, data);
566 break;
567
568 case OPIOCNEXTPROP:
569 err = opiocnextprop(argp, data);
570 break;
571
572 case OPIOCSET:
573 err = opiocset(argp, data);
574 break;
575
576 case OPIOCGETOPTNODE:
577 BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
578
579 err = 0;
580 if (copy_to_user(argp, &options_node->phandle, sizeof(phandle)))
581 err = -EFAULT;
582 break;
583
584 case OPIOCGETNEXT:
585 case OPIOCGETCHILD:
586 err = opiocgetnext(cmd, argp);
587 break;
588
589 default:
590 err = -EINVAL;
591 break;
592 };
593 mutex_unlock(&openprom_mutex);
594
595 return err;
596 }
597
598
599 /*
600 * Handoff control to the correct ioctl handler.
601 */
openprom_ioctl(struct file * file,unsigned int cmd,unsigned long arg)602 static long openprom_ioctl(struct file * file,
603 unsigned int cmd, unsigned long arg)
604 {
605 DATA *data = file->private_data;
606
607 switch (cmd) {
608 case OPROMGETOPT:
609 case OPROMNXTOPT:
610 if ((file->f_mode & FMODE_READ) == 0)
611 return -EPERM;
612 return openprom_sunos_ioctl(file, cmd, arg,
613 options_node);
614
615 case OPROMSETOPT:
616 case OPROMSETOPT2:
617 if ((file->f_mode & FMODE_WRITE) == 0)
618 return -EPERM;
619 return openprom_sunos_ioctl(file, cmd, arg,
620 options_node);
621
622 case OPROMNEXT:
623 case OPROMCHILD:
624 case OPROMGETPROP:
625 case OPROMNXTPROP:
626 if ((file->f_mode & FMODE_READ) == 0)
627 return -EPERM;
628 return openprom_sunos_ioctl(file, cmd, arg,
629 data->current_node);
630
631 case OPROMU2P:
632 case OPROMGETCONS:
633 case OPROMGETFBNAME:
634 case OPROMGETBOOTARGS:
635 case OPROMSETCUR:
636 case OPROMPCI2NODE:
637 case OPROMPATH2NODE:
638 if ((file->f_mode & FMODE_READ) == 0)
639 return -EPERM;
640 return openprom_sunos_ioctl(file, cmd, arg, NULL);
641
642 case OPIOCGET:
643 case OPIOCNEXTPROP:
644 case OPIOCGETOPTNODE:
645 case OPIOCGETNEXT:
646 case OPIOCGETCHILD:
647 if ((file->f_mode & FMODE_READ) == 0)
648 return -EBADF;
649 return openprom_bsd_ioctl(file,cmd,arg);
650
651 case OPIOCSET:
652 if ((file->f_mode & FMODE_WRITE) == 0)
653 return -EBADF;
654 return openprom_bsd_ioctl(file,cmd,arg);
655
656 default:
657 return -EINVAL;
658 };
659 }
660
openprom_compat_ioctl(struct file * file,unsigned int cmd,unsigned long arg)661 static long openprom_compat_ioctl(struct file *file, unsigned int cmd,
662 unsigned long arg)
663 {
664 long rval = -ENOTTY;
665
666 /*
667 * SunOS/Solaris only, the NetBSD one's have embedded pointers in
668 * the arg which we'd need to clean up...
669 */
670 switch (cmd) {
671 case OPROMGETOPT:
672 case OPROMSETOPT:
673 case OPROMNXTOPT:
674 case OPROMSETOPT2:
675 case OPROMNEXT:
676 case OPROMCHILD:
677 case OPROMGETPROP:
678 case OPROMNXTPROP:
679 case OPROMU2P:
680 case OPROMGETCONS:
681 case OPROMGETFBNAME:
682 case OPROMGETBOOTARGS:
683 case OPROMSETCUR:
684 case OPROMPCI2NODE:
685 case OPROMPATH2NODE:
686 rval = openprom_ioctl(file, cmd, arg);
687 break;
688 }
689
690 return rval;
691 }
692
openprom_open(struct inode * inode,struct file * file)693 static int openprom_open(struct inode * inode, struct file * file)
694 {
695 DATA *data;
696
697 data = kmalloc(sizeof(DATA), GFP_KERNEL);
698 if (!data)
699 return -ENOMEM;
700
701 mutex_lock(&openprom_mutex);
702 data->current_node = of_find_node_by_path("/");
703 data->lastnode = data->current_node;
704 file->private_data = (void *) data;
705 mutex_unlock(&openprom_mutex);
706
707 return 0;
708 }
709
openprom_release(struct inode * inode,struct file * file)710 static int openprom_release(struct inode * inode, struct file * file)
711 {
712 kfree(file->private_data);
713 return 0;
714 }
715
716 static const struct file_operations openprom_fops = {
717 .owner = THIS_MODULE,
718 .llseek = no_llseek,
719 .unlocked_ioctl = openprom_ioctl,
720 .compat_ioctl = openprom_compat_ioctl,
721 .open = openprom_open,
722 .release = openprom_release,
723 };
724
725 static struct miscdevice openprom_dev = {
726 .minor = SUN_OPENPROM_MINOR,
727 .name = "openprom",
728 .fops = &openprom_fops,
729 };
730
openprom_init(void)731 static int __init openprom_init(void)
732 {
733 struct device_node *dp;
734 int err;
735
736 err = misc_register(&openprom_dev);
737 if (err)
738 return err;
739
740 dp = of_find_node_by_path("/");
741 dp = dp->child;
742 while (dp) {
743 if (!strcmp(dp->name, "options"))
744 break;
745 dp = dp->sibling;
746 }
747 options_node = dp;
748
749 if (!options_node) {
750 misc_deregister(&openprom_dev);
751 return -EIO;
752 }
753
754 return 0;
755 }
756
openprom_cleanup(void)757 static void __exit openprom_cleanup(void)
758 {
759 misc_deregister(&openprom_dev);
760 }
761
762 module_init(openprom_init);
763 module_exit(openprom_cleanup);
764