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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
4 */
5
6#include <linux/device.h>
7#include <linux/fs.h>
8#include <linux/mm.h>
9#include <linux/err.h>
10#include <linux/init.h>
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/sched.h>
15#include <linux/mutex.h>
16#include <linux/backing-dev.h>
17#include <linux/compat.h>
18#include <linux/mount.h>
19#include <linux/blkpg.h>
20#include <linux/magic.h>
21#include <linux/major.h>
22#include <linux/mtd/mtd.h>
23#include <linux/mtd/partitions.h>
24#include <linux/mtd/map.h>
25
26#include <linux/uaccess.h>
27
28#include "mtdcore.h"
29
30static DEFINE_MUTEX(mtd_mutex);
31
32/*
33 * Data structure to hold the pointer to the mtd device as well
34 * as mode information of various use cases.
35 */
36struct mtd_file_info {
37 struct mtd_info *mtd;
38 enum mtd_file_modes mode;
39};
40
41static loff_t mtdchar_lseek(struct file *file, loff_t offset, int orig)
42{
43 struct mtd_file_info *mfi = file->private_data;
44 return fixed_size_llseek(file, offset, orig, mfi->mtd->size);
45}
46
47static int mtdchar_open(struct inode *inode, struct file *file)
48{
49 int minor = iminor(inode);
50 int devnum = minor >> 1;
51 int ret = 0;
52 struct mtd_info *mtd;
53 struct mtd_file_info *mfi;
54
55 pr_debug("MTD_open\n");
56
57 /* You can't open the RO devices RW */
58 if ((file->f_mode & FMODE_WRITE) && (minor & 1))
59 return -EACCES;
60
61 mutex_lock(&mtd_mutex);
62 mtd = get_mtd_device(NULL, devnum);
63
64 if (IS_ERR(mtd)) {
65 ret = PTR_ERR(mtd);
66 goto out;
67 }
68
69 if (mtd->type == MTD_ABSENT) {
70 ret = -ENODEV;
71 goto out1;
72 }
73
74 /* You can't open it RW if it's not a writeable device */
75 if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
76 ret = -EACCES;
77 goto out1;
78 }
79
80 mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
81 if (!mfi) {
82 ret = -ENOMEM;
83 goto out1;
84 }
85 mfi->mtd = mtd;
86 file->private_data = mfi;
87 mutex_unlock(&mtd_mutex);
88 return 0;
89
90out1:
91 put_mtd_device(mtd);
92out:
93 mutex_unlock(&mtd_mutex);
94 return ret;
95} /* mtdchar_open */
96
97/*====================================================================*/
98
99static int mtdchar_close(struct inode *inode, struct file *file)
100{
101 struct mtd_file_info *mfi = file->private_data;
102 struct mtd_info *mtd = mfi->mtd;
103
104 pr_debug("MTD_close\n");
105
106 /* Only sync if opened RW */
107 if ((file->f_mode & FMODE_WRITE))
108 mtd_sync(mtd);
109
110 put_mtd_device(mtd);
111 file->private_data = NULL;
112 kfree(mfi);
113
114 return 0;
115} /* mtdchar_close */
116
117/* Back in June 2001, dwmw2 wrote:
118 *
119 * FIXME: This _really_ needs to die. In 2.5, we should lock the
120 * userspace buffer down and use it directly with readv/writev.
121 *
122 * The implementation below, using mtd_kmalloc_up_to, mitigates
123 * allocation failures when the system is under low-memory situations
124 * or if memory is highly fragmented at the cost of reducing the
125 * performance of the requested transfer due to a smaller buffer size.
126 *
127 * A more complex but more memory-efficient implementation based on
128 * get_user_pages and iovecs to cover extents of those pages is a
129 * longer-term goal, as intimated by dwmw2 above. However, for the
130 * write case, this requires yet more complex head and tail transfer
131 * handling when those head and tail offsets and sizes are such that
132 * alignment requirements are not met in the NAND subdriver.
133 */
134
135static ssize_t mtdchar_read(struct file *file, char __user *buf, size_t count,
136 loff_t *ppos)
137{
138 struct mtd_file_info *mfi = file->private_data;
139 struct mtd_info *mtd = mfi->mtd;
140 size_t retlen;
141 size_t total_retlen=0;
142 int ret=0;
143 int len;
144 size_t size = count;
145 char *kbuf;
146
147 pr_debug("MTD_read\n");
148
149 if (*ppos + count > mtd->size) {
150 if (*ppos < mtd->size)
151 count = mtd->size - *ppos;
152 else
153 count = 0;
154 }
155
156 if (!count)
157 return 0;
158
159 kbuf = mtd_kmalloc_up_to(mtd, &size);
160 if (!kbuf)
161 return -ENOMEM;
162
163 while (count) {
164 len = min_t(size_t, count, size);
165
166 switch (mfi->mode) {
167 case MTD_FILE_MODE_OTP_FACTORY:
168 ret = mtd_read_fact_prot_reg(mtd, *ppos, len,
169 &retlen, kbuf);
170 break;
171 case MTD_FILE_MODE_OTP_USER:
172 ret = mtd_read_user_prot_reg(mtd, *ppos, len,
173 &retlen, kbuf);
174 break;
175 case MTD_FILE_MODE_RAW:
176 {
177 struct mtd_oob_ops ops = {};
178
179 ops.mode = MTD_OPS_RAW;
180 ops.datbuf = kbuf;
181 ops.oobbuf = NULL;
182 ops.len = len;
183
184 ret = mtd_read_oob(mtd, *ppos, &ops);
185 retlen = ops.retlen;
186 break;
187 }
188 default:
189 ret = mtd_read(mtd, *ppos, len, &retlen, kbuf);
190 }
191 /* Nand returns -EBADMSG on ECC errors, but it returns
192 * the data. For our userspace tools it is important
193 * to dump areas with ECC errors!
194 * For kernel internal usage it also might return -EUCLEAN
195 * to signal the caller that a bitflip has occurred and has
196 * been corrected by the ECC algorithm.
197 * Userspace software which accesses NAND this way
198 * must be aware of the fact that it deals with NAND
199 */
200 if (!ret || mtd_is_bitflip_or_eccerr(ret)) {
201 *ppos += retlen;
202 if (copy_to_user(buf, kbuf, retlen)) {
203 kfree(kbuf);
204 return -EFAULT;
205 }
206 else
207 total_retlen += retlen;
208
209 count -= retlen;
210 buf += retlen;
211 if (retlen == 0)
212 count = 0;
213 }
214 else {
215 kfree(kbuf);
216 return ret;
217 }
218
219 }
220
221 kfree(kbuf);
222 return total_retlen;
223} /* mtdchar_read */
224
225static ssize_t mtdchar_write(struct file *file, const char __user *buf, size_t count,
226 loff_t *ppos)
227{
228 struct mtd_file_info *mfi = file->private_data;
229 struct mtd_info *mtd = mfi->mtd;
230 size_t size = count;
231 char *kbuf;
232 size_t retlen;
233 size_t total_retlen=0;
234 int ret=0;
235 int len;
236
237 pr_debug("MTD_write\n");
238
239 if (*ppos >= mtd->size)
240 return -ENOSPC;
241
242 if (*ppos + count > mtd->size)
243 count = mtd->size - *ppos;
244
245 if (!count)
246 return 0;
247
248 kbuf = mtd_kmalloc_up_to(mtd, &size);
249 if (!kbuf)
250 return -ENOMEM;
251
252 while (count) {
253 len = min_t(size_t, count, size);
254
255 if (copy_from_user(kbuf, buf, len)) {
256 kfree(kbuf);
257 return -EFAULT;
258 }
259
260 switch (mfi->mode) {
261 case MTD_FILE_MODE_OTP_FACTORY:
262 ret = -EROFS;
263 break;
264 case MTD_FILE_MODE_OTP_USER:
265 ret = mtd_write_user_prot_reg(mtd, *ppos, len,
266 &retlen, kbuf);
267 break;
268
269 case MTD_FILE_MODE_RAW:
270 {
271 struct mtd_oob_ops ops = {};
272
273 ops.mode = MTD_OPS_RAW;
274 ops.datbuf = kbuf;
275 ops.oobbuf = NULL;
276 ops.ooboffs = 0;
277 ops.len = len;
278
279 ret = mtd_write_oob(mtd, *ppos, &ops);
280 retlen = ops.retlen;
281 break;
282 }
283
284 default:
285 ret = mtd_write(mtd, *ppos, len, &retlen, kbuf);
286 }
287
288 /*
289 * Return -ENOSPC only if no data could be written at all.
290 * Otherwise just return the number of bytes that actually
291 * have been written.
292 */
293 if ((ret == -ENOSPC) && (total_retlen))
294 break;
295
296 if (!ret) {
297 *ppos += retlen;
298 total_retlen += retlen;
299 count -= retlen;
300 buf += retlen;
301 }
302 else {
303 kfree(kbuf);
304 return ret;
305 }
306 }
307
308 kfree(kbuf);
309 return total_retlen;
310} /* mtdchar_write */
311
312/*======================================================================
313
314 IOCTL calls for getting device parameters.
315
316======================================================================*/
317
318static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
319{
320 struct mtd_info *mtd = mfi->mtd;
321 size_t retlen;
322
323 switch (mode) {
324 case MTD_OTP_FACTORY:
325 if (mtd_read_fact_prot_reg(mtd, -1, 0, &retlen, NULL) ==
326 -EOPNOTSUPP)
327 return -EOPNOTSUPP;
328
329 mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
330 break;
331 case MTD_OTP_USER:
332 if (mtd_read_user_prot_reg(mtd, -1, 0, &retlen, NULL) ==
333 -EOPNOTSUPP)
334 return -EOPNOTSUPP;
335
336 mfi->mode = MTD_FILE_MODE_OTP_USER;
337 break;
338 case MTD_OTP_OFF:
339 mfi->mode = MTD_FILE_MODE_NORMAL;
340 break;
341 default:
342 return -EINVAL;
343 }
344
345 return 0;
346}
347
348static int mtdchar_writeoob(struct file *file, struct mtd_info *mtd,
349 uint64_t start, uint32_t length, void __user *ptr,
350 uint32_t __user *retp)
351{
352 struct mtd_info *master = mtd_get_master(mtd);
353 struct mtd_file_info *mfi = file->private_data;
354 struct mtd_oob_ops ops = {};
355 uint32_t retlen;
356 int ret = 0;
357
358 if (length > 4096)
359 return -EINVAL;
360
361 if (!master->_write_oob)
362 return -EOPNOTSUPP;
363
364 ops.ooblen = length;
365 ops.ooboffs = start & (mtd->writesize - 1);
366 ops.datbuf = NULL;
367 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
368 MTD_OPS_PLACE_OOB;
369
370 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
371 return -EINVAL;
372
373 ops.oobbuf = memdup_user(ptr, length);
374 if (IS_ERR(ops.oobbuf))
375 return PTR_ERR(ops.oobbuf);
376
377 start &= ~((uint64_t)mtd->writesize - 1);
378 ret = mtd_write_oob(mtd, start, &ops);
379
380 if (ops.oobretlen > 0xFFFFFFFFU)
381 ret = -EOVERFLOW;
382 retlen = ops.oobretlen;
383 if (copy_to_user(retp, &retlen, sizeof(length)))
384 ret = -EFAULT;
385
386 kfree(ops.oobbuf);
387 return ret;
388}
389
390static int mtdchar_readoob(struct file *file, struct mtd_info *mtd,
391 uint64_t start, uint32_t length, void __user *ptr,
392 uint32_t __user *retp)
393{
394 struct mtd_file_info *mfi = file->private_data;
395 struct mtd_oob_ops ops = {};
396 int ret = 0;
397
398 if (length > 4096)
399 return -EINVAL;
400
401 ops.ooblen = length;
402 ops.ooboffs = start & (mtd->writesize - 1);
403 ops.datbuf = NULL;
404 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
405 MTD_OPS_PLACE_OOB;
406
407 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
408 return -EINVAL;
409
410 ops.oobbuf = kmalloc(length, GFP_KERNEL);
411 if (!ops.oobbuf)
412 return -ENOMEM;
413
414 start &= ~((uint64_t)mtd->writesize - 1);
415 ret = mtd_read_oob(mtd, start, &ops);
416
417 if (put_user(ops.oobretlen, retp))
418 ret = -EFAULT;
419 else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
420 ops.oobretlen))
421 ret = -EFAULT;
422
423 kfree(ops.oobbuf);
424
425 /*
426 * NAND returns -EBADMSG on ECC errors, but it returns the OOB
427 * data. For our userspace tools it is important to dump areas
428 * with ECC errors!
429 * For kernel internal usage it also might return -EUCLEAN
430 * to signal the caller that a bitflip has occurred and has
431 * been corrected by the ECC algorithm.
432 *
433 * Note: currently the standard NAND function, nand_read_oob_std,
434 * does not calculate ECC for the OOB area, so do not rely on
435 * this behavior unless you have replaced it with your own.
436 */
437 if (mtd_is_bitflip_or_eccerr(ret))
438 return 0;
439
440 return ret;
441}
442
443/*
444 * Copies (and truncates, if necessary) OOB layout information to the
445 * deprecated layout struct, nand_ecclayout_user. This is necessary only to
446 * support the deprecated API ioctl ECCGETLAYOUT while allowing all new
447 * functionality to use mtd_ooblayout_ops flexibly (i.e. mtd_ooblayout_ops
448 * can describe any kind of OOB layout with almost zero overhead from a
449 * memory usage point of view).
450 */
451static int shrink_ecclayout(struct mtd_info *mtd,
452 struct nand_ecclayout_user *to)
453{
454 struct mtd_oob_region oobregion;
455 int i, section = 0, ret;
456
457 if (!mtd || !to)
458 return -EINVAL;
459
460 memset(to, 0, sizeof(*to));
461
462 to->eccbytes = 0;
463 for (i = 0; i < MTD_MAX_ECCPOS_ENTRIES;) {
464 u32 eccpos;
465
466 ret = mtd_ooblayout_ecc(mtd, section++, &oobregion);
467 if (ret < 0) {
468 if (ret != -ERANGE)
469 return ret;
470
471 break;
472 }
473
474 eccpos = oobregion.offset;
475 for (; i < MTD_MAX_ECCPOS_ENTRIES &&
476 eccpos < oobregion.offset + oobregion.length; i++) {
477 to->eccpos[i] = eccpos++;
478 to->eccbytes++;
479 }
480 }
481
482 for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
483 ret = mtd_ooblayout_free(mtd, i, &oobregion);
484 if (ret < 0) {
485 if (ret != -ERANGE)
486 return ret;
487
488 break;
489 }
490
491 to->oobfree[i].offset = oobregion.offset;
492 to->oobfree[i].length = oobregion.length;
493 to->oobavail += to->oobfree[i].length;
494 }
495
496 return 0;
497}
498
499static int get_oobinfo(struct mtd_info *mtd, struct nand_oobinfo *to)
500{
501 struct mtd_oob_region oobregion;
502 int i, section = 0, ret;
503
504 if (!mtd || !to)
505 return -EINVAL;
506
507 memset(to, 0, sizeof(*to));
508
509 to->eccbytes = 0;
510 for (i = 0; i < ARRAY_SIZE(to->eccpos);) {
511 u32 eccpos;
512
513 ret = mtd_ooblayout_ecc(mtd, section++, &oobregion);
514 if (ret < 0) {
515 if (ret != -ERANGE)
516 return ret;
517
518 break;
519 }
520
521 if (oobregion.length + i > ARRAY_SIZE(to->eccpos))
522 return -EINVAL;
523
524 eccpos = oobregion.offset;
525 for (; eccpos < oobregion.offset + oobregion.length; i++) {
526 to->eccpos[i] = eccpos++;
527 to->eccbytes++;
528 }
529 }
530
531 for (i = 0; i < 8; i++) {
532 ret = mtd_ooblayout_free(mtd, i, &oobregion);
533 if (ret < 0) {
534 if (ret != -ERANGE)
535 return ret;
536
537 break;
538 }
539
540 to->oobfree[i][0] = oobregion.offset;
541 to->oobfree[i][1] = oobregion.length;
542 }
543
544 to->useecc = MTD_NANDECC_AUTOPLACE;
545
546 return 0;
547}
548
549static int mtdchar_blkpg_ioctl(struct mtd_info *mtd,
550 struct blkpg_ioctl_arg *arg)
551{
552 struct blkpg_partition p;
553
554 if (!capable(CAP_SYS_ADMIN))
555 return -EPERM;
556
557 if (copy_from_user(&p, arg->data, sizeof(p)))
558 return -EFAULT;
559
560 switch (arg->op) {
561 case BLKPG_ADD_PARTITION:
562
563 /* Only master mtd device must be used to add partitions */
564 if (mtd_is_partition(mtd))
565 return -EINVAL;
566
567 /* Sanitize user input */
568 p.devname[BLKPG_DEVNAMELTH - 1] = '\0';
569
570 return mtd_add_partition(mtd, p.devname, p.start, p.length);
571
572 case BLKPG_DEL_PARTITION:
573
574 if (p.pno < 0)
575 return -EINVAL;
576
577 return mtd_del_partition(mtd, p.pno);
578
579 default:
580 return -EINVAL;
581 }
582}
583
584static int mtdchar_write_ioctl(struct mtd_info *mtd,
585 struct mtd_write_req __user *argp)
586{
587 struct mtd_info *master = mtd_get_master(mtd);
588 struct mtd_write_req req;
589 struct mtd_oob_ops ops = {};
590 const void __user *usr_data, *usr_oob;
591 int ret;
592
593 if (copy_from_user(&req, argp, sizeof(req)))
594 return -EFAULT;
595
596 usr_data = (const void __user *)(uintptr_t)req.usr_data;
597 usr_oob = (const void __user *)(uintptr_t)req.usr_oob;
598
599 if (!master->_write_oob)
600 return -EOPNOTSUPP;
601 ops.mode = req.mode;
602 ops.len = (size_t)req.len;
603 ops.ooblen = (size_t)req.ooblen;
604 ops.ooboffs = 0;
605
606 if (usr_data) {
607 ops.datbuf = memdup_user(usr_data, ops.len);
608 if (IS_ERR(ops.datbuf))
609 return PTR_ERR(ops.datbuf);
610 } else {
611 ops.datbuf = NULL;
612 }
613
614 if (usr_oob) {
615 ops.oobbuf = memdup_user(usr_oob, ops.ooblen);
616 if (IS_ERR(ops.oobbuf)) {
617 kfree(ops.datbuf);
618 return PTR_ERR(ops.oobbuf);
619 }
620 } else {
621 ops.oobbuf = NULL;
622 }
623
624 ret = mtd_write_oob(mtd, (loff_t)req.start, &ops);
625
626 kfree(ops.datbuf);
627 kfree(ops.oobbuf);
628
629 return ret;
630}
631
632static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
633{
634 struct mtd_file_info *mfi = file->private_data;
635 struct mtd_info *mtd = mfi->mtd;
636 struct mtd_info *master = mtd_get_master(mtd);
637 void __user *argp = (void __user *)arg;
638 int ret = 0;
639 struct mtd_info_user info;
640
641 pr_debug("MTD_ioctl\n");
642
643 /*
644 * Check the file mode to require "dangerous" commands to have write
645 * permissions.
646 */
647 switch (cmd) {
648 /* "safe" commands */
649 case MEMGETREGIONCOUNT:
650 case MEMGETREGIONINFO:
651 case MEMGETINFO:
652 case MEMREADOOB:
653 case MEMREADOOB64:
654 case MEMLOCK:
655 case MEMUNLOCK:
656 case MEMISLOCKED:
657 case MEMGETOOBSEL:
658 case MEMGETBADBLOCK:
659 case MEMSETBADBLOCK:
660 case OTPSELECT:
661 case OTPGETREGIONCOUNT:
662 case OTPGETREGIONINFO:
663 case OTPLOCK:
664 case ECCGETLAYOUT:
665 case ECCGETSTATS:
666 case MTDFILEMODE:
667 case BLKPG:
668 case BLKRRPART:
669 break;
670
671 /* "dangerous" commands */
672 case MEMERASE:
673 case MEMERASE64:
674 case MEMWRITEOOB:
675 case MEMWRITEOOB64:
676 case MEMWRITE:
677 if (!(file->f_mode & FMODE_WRITE))
678 return -EPERM;
679 break;
680
681 default:
682 return -ENOTTY;
683 }
684
685 switch (cmd) {
686 case MEMGETREGIONCOUNT:
687 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
688 return -EFAULT;
689 break;
690
691 case MEMGETREGIONINFO:
692 {
693 uint32_t ur_idx;
694 struct mtd_erase_region_info *kr;
695 struct region_info_user __user *ur = argp;
696
697 if (get_user(ur_idx, &(ur->regionindex)))
698 return -EFAULT;
699
700 if (ur_idx >= mtd->numeraseregions)
701 return -EINVAL;
702
703 kr = &(mtd->eraseregions[ur_idx]);
704
705 if (put_user(kr->offset, &(ur->offset))
706 || put_user(kr->erasesize, &(ur->erasesize))
707 || put_user(kr->numblocks, &(ur->numblocks)))
708 return -EFAULT;
709
710 break;
711 }
712
713 case MEMGETINFO:
714 memset(&info, 0, sizeof(info));
715 info.type = mtd->type;
716 info.flags = mtd->flags;
717 info.size = mtd->size;
718 info.erasesize = mtd->erasesize;
719 info.writesize = mtd->writesize;
720 info.oobsize = mtd->oobsize;
721 /* The below field is obsolete */
722 info.padding = 0;
723 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
724 return -EFAULT;
725 break;
726
727 case MEMERASE:
728 case MEMERASE64:
729 {
730 struct erase_info *erase;
731
732 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
733 if (!erase)
734 ret = -ENOMEM;
735 else {
736 if (cmd == MEMERASE64) {
737 struct erase_info_user64 einfo64;
738
739 if (copy_from_user(&einfo64, argp,
740 sizeof(struct erase_info_user64))) {
741 kfree(erase);
742 return -EFAULT;
743 }
744 erase->addr = einfo64.start;
745 erase->len = einfo64.length;
746 } else {
747 struct erase_info_user einfo32;
748
749 if (copy_from_user(&einfo32, argp,
750 sizeof(struct erase_info_user))) {
751 kfree(erase);
752 return -EFAULT;
753 }
754 erase->addr = einfo32.start;
755 erase->len = einfo32.length;
756 }
757
758 ret = mtd_erase(mtd, erase);
759 kfree(erase);
760 }
761 break;
762 }
763
764 case MEMWRITEOOB:
765 {
766 struct mtd_oob_buf buf;
767 struct mtd_oob_buf __user *buf_user = argp;
768
769 /* NOTE: writes return length to buf_user->length */
770 if (copy_from_user(&buf, argp, sizeof(buf)))
771 ret = -EFAULT;
772 else
773 ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
774 buf.ptr, &buf_user->length);
775 break;
776 }
777
778 case MEMREADOOB:
779 {
780 struct mtd_oob_buf buf;
781 struct mtd_oob_buf __user *buf_user = argp;
782
783 /* NOTE: writes return length to buf_user->start */
784 if (copy_from_user(&buf, argp, sizeof(buf)))
785 ret = -EFAULT;
786 else
787 ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
788 buf.ptr, &buf_user->start);
789 break;
790 }
791
792 case MEMWRITEOOB64:
793 {
794 struct mtd_oob_buf64 buf;
795 struct mtd_oob_buf64 __user *buf_user = argp;
796
797 if (copy_from_user(&buf, argp, sizeof(buf)))
798 ret = -EFAULT;
799 else
800 ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
801 (void __user *)(uintptr_t)buf.usr_ptr,
802 &buf_user->length);
803 break;
804 }
805
806 case MEMREADOOB64:
807 {
808 struct mtd_oob_buf64 buf;
809 struct mtd_oob_buf64 __user *buf_user = argp;
810
811 if (copy_from_user(&buf, argp, sizeof(buf)))
812 ret = -EFAULT;
813 else
814 ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
815 (void __user *)(uintptr_t)buf.usr_ptr,
816 &buf_user->length);
817 break;
818 }
819
820 case MEMWRITE:
821 {
822 ret = mtdchar_write_ioctl(mtd,
823 (struct mtd_write_req __user *)arg);
824 break;
825 }
826
827 case MEMLOCK:
828 {
829 struct erase_info_user einfo;
830
831 if (copy_from_user(&einfo, argp, sizeof(einfo)))
832 return -EFAULT;
833
834 ret = mtd_lock(mtd, einfo.start, einfo.length);
835 break;
836 }
837
838 case MEMUNLOCK:
839 {
840 struct erase_info_user einfo;
841
842 if (copy_from_user(&einfo, argp, sizeof(einfo)))
843 return -EFAULT;
844
845 ret = mtd_unlock(mtd, einfo.start, einfo.length);
846 break;
847 }
848
849 case MEMISLOCKED:
850 {
851 struct erase_info_user einfo;
852
853 if (copy_from_user(&einfo, argp, sizeof(einfo)))
854 return -EFAULT;
855
856 ret = mtd_is_locked(mtd, einfo.start, einfo.length);
857 break;
858 }
859
860 /* Legacy interface */
861 case MEMGETOOBSEL:
862 {
863 struct nand_oobinfo oi;
864
865 if (!master->ooblayout)
866 return -EOPNOTSUPP;
867
868 ret = get_oobinfo(mtd, &oi);
869 if (ret)
870 return ret;
871
872 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
873 return -EFAULT;
874 break;
875 }
876
877 case MEMGETBADBLOCK:
878 {
879 loff_t offs;
880
881 if (copy_from_user(&offs, argp, sizeof(loff_t)))
882 return -EFAULT;
883 return mtd_block_isbad(mtd, offs);
884 break;
885 }
886
887 case MEMSETBADBLOCK:
888 {
889 loff_t offs;
890
891 if (copy_from_user(&offs, argp, sizeof(loff_t)))
892 return -EFAULT;
893 return mtd_block_markbad(mtd, offs);
894 break;
895 }
896
897 case OTPSELECT:
898 {
899 int mode;
900 if (copy_from_user(&mode, argp, sizeof(int)))
901 return -EFAULT;
902
903 mfi->mode = MTD_FILE_MODE_NORMAL;
904
905 ret = otp_select_filemode(mfi, mode);
906
907 file->f_pos = 0;
908 break;
909 }
910
911 case OTPGETREGIONCOUNT:
912 case OTPGETREGIONINFO:
913 {
914 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
915 size_t retlen;
916 if (!buf)
917 return -ENOMEM;
918 switch (mfi->mode) {
919 case MTD_FILE_MODE_OTP_FACTORY:
920 ret = mtd_get_fact_prot_info(mtd, 4096, &retlen, buf);
921 break;
922 case MTD_FILE_MODE_OTP_USER:
923 ret = mtd_get_user_prot_info(mtd, 4096, &retlen, buf);
924 break;
925 default:
926 ret = -EINVAL;
927 break;
928 }
929 if (!ret) {
930 if (cmd == OTPGETREGIONCOUNT) {
931 int nbr = retlen / sizeof(struct otp_info);
932 ret = copy_to_user(argp, &nbr, sizeof(int));
933 } else
934 ret = copy_to_user(argp, buf, retlen);
935 if (ret)
936 ret = -EFAULT;
937 }
938 kfree(buf);
939 break;
940 }
941
942 case OTPLOCK:
943 {
944 struct otp_info oinfo;
945
946 if (mfi->mode != MTD_FILE_MODE_OTP_USER)
947 return -EINVAL;
948 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
949 return -EFAULT;
950 ret = mtd_lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
951 break;
952 }
953
954 /* This ioctl is being deprecated - it truncates the ECC layout */
955 case ECCGETLAYOUT:
956 {
957 struct nand_ecclayout_user *usrlay;
958
959 if (!master->ooblayout)
960 return -EOPNOTSUPP;
961
962 usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
963 if (!usrlay)
964 return -ENOMEM;
965
966 shrink_ecclayout(mtd, usrlay);
967
968 if (copy_to_user(argp, usrlay, sizeof(*usrlay)))
969 ret = -EFAULT;
970 kfree(usrlay);
971 break;
972 }
973
974 case ECCGETSTATS:
975 {
976 if (copy_to_user(argp, &mtd->ecc_stats,
977 sizeof(struct mtd_ecc_stats)))
978 return -EFAULT;
979 break;
980 }
981
982 case MTDFILEMODE:
983 {
984 mfi->mode = 0;
985
986 switch(arg) {
987 case MTD_FILE_MODE_OTP_FACTORY:
988 case MTD_FILE_MODE_OTP_USER:
989 ret = otp_select_filemode(mfi, arg);
990 break;
991
992 case MTD_FILE_MODE_RAW:
993 if (!mtd_has_oob(mtd))
994 return -EOPNOTSUPP;
995 mfi->mode = arg;
996
997 case MTD_FILE_MODE_NORMAL:
998 break;
999 default:
1000 ret = -EINVAL;
1001 }
1002 file->f_pos = 0;
1003 break;
1004 }
1005
1006 case BLKPG:
1007 {
1008 struct blkpg_ioctl_arg __user *blk_arg = argp;
1009 struct blkpg_ioctl_arg a;
1010
1011 if (copy_from_user(&a, blk_arg, sizeof(a)))
1012 ret = -EFAULT;
1013 else
1014 ret = mtdchar_blkpg_ioctl(mtd, &a);
1015 break;
1016 }
1017
1018 case BLKRRPART:
1019 {
1020 /* No reread partition feature. Just return ok */
1021 ret = 0;
1022 break;
1023 }
1024 }
1025
1026 return ret;
1027} /* memory_ioctl */
1028
1029static long mtdchar_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
1030{
1031 int ret;
1032
1033 mutex_lock(&mtd_mutex);
1034 ret = mtdchar_ioctl(file, cmd, arg);
1035 mutex_unlock(&mtd_mutex);
1036
1037 return ret;
1038}
1039
1040#ifdef CONFIG_COMPAT
1041
1042struct mtd_oob_buf32 {
1043 u_int32_t start;
1044 u_int32_t length;
1045 compat_caddr_t ptr; /* unsigned char* */
1046};
1047
1048#define MEMWRITEOOB32 _IOWR('M', 3, struct mtd_oob_buf32)
1049#define MEMREADOOB32 _IOWR('M', 4, struct mtd_oob_buf32)
1050
1051static long mtdchar_compat_ioctl(struct file *file, unsigned int cmd,
1052 unsigned long arg)
1053{
1054 struct mtd_file_info *mfi = file->private_data;
1055 struct mtd_info *mtd = mfi->mtd;
1056 void __user *argp = compat_ptr(arg);
1057 int ret = 0;
1058
1059 mutex_lock(&mtd_mutex);
1060
1061 switch (cmd) {
1062 case MEMWRITEOOB32:
1063 {
1064 struct mtd_oob_buf32 buf;
1065 struct mtd_oob_buf32 __user *buf_user = argp;
1066
1067 if (!(file->f_mode & FMODE_WRITE)) {
1068 ret = -EPERM;
1069 break;
1070 }
1071
1072 if (copy_from_user(&buf, argp, sizeof(buf)))
1073 ret = -EFAULT;
1074 else
1075 ret = mtdchar_writeoob(file, mtd, buf.start,
1076 buf.length, compat_ptr(buf.ptr),
1077 &buf_user->length);
1078 break;
1079 }
1080
1081 case MEMREADOOB32:
1082 {
1083 struct mtd_oob_buf32 buf;
1084 struct mtd_oob_buf32 __user *buf_user = argp;
1085
1086 /* NOTE: writes return length to buf->start */
1087 if (copy_from_user(&buf, argp, sizeof(buf)))
1088 ret = -EFAULT;
1089 else
1090 ret = mtdchar_readoob(file, mtd, buf.start,
1091 buf.length, compat_ptr(buf.ptr),
1092 &buf_user->start);
1093 break;
1094 }
1095
1096 case BLKPG:
1097 {
1098 /* Convert from blkpg_compat_ioctl_arg to blkpg_ioctl_arg */
1099 struct blkpg_compat_ioctl_arg __user *uarg = argp;
1100 struct blkpg_compat_ioctl_arg compat_arg;
1101 struct blkpg_ioctl_arg a;
1102
1103 if (copy_from_user(&compat_arg, uarg, sizeof(compat_arg))) {
1104 ret = -EFAULT;
1105 break;
1106 }
1107
1108 memset(&a, 0, sizeof(a));
1109 a.op = compat_arg.op;
1110 a.flags = compat_arg.flags;
1111 a.datalen = compat_arg.datalen;
1112 a.data = compat_ptr(compat_arg.data);
1113
1114 ret = mtdchar_blkpg_ioctl(mtd, &a);
1115 break;
1116 }
1117
1118 default:
1119 ret = mtdchar_ioctl(file, cmd, (unsigned long)argp);
1120 }
1121
1122 mutex_unlock(&mtd_mutex);
1123
1124 return ret;
1125}
1126
1127#endif /* CONFIG_COMPAT */
1128
1129/*
1130 * try to determine where a shared mapping can be made
1131 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
1132 * mappings)
1133 */
1134#ifndef CONFIG_MMU
1135static unsigned long mtdchar_get_unmapped_area(struct file *file,
1136 unsigned long addr,
1137 unsigned long len,
1138 unsigned long pgoff,
1139 unsigned long flags)
1140{
1141 struct mtd_file_info *mfi = file->private_data;
1142 struct mtd_info *mtd = mfi->mtd;
1143 unsigned long offset;
1144 int ret;
1145
1146 if (addr != 0)
1147 return (unsigned long) -EINVAL;
1148
1149 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
1150 return (unsigned long) -EINVAL;
1151
1152 offset = pgoff << PAGE_SHIFT;
1153 if (offset > mtd->size - len)
1154 return (unsigned long) -EINVAL;
1155
1156 ret = mtd_get_unmapped_area(mtd, len, offset, flags);
1157 return ret == -EOPNOTSUPP ? -ENODEV : ret;
1158}
1159
1160static unsigned mtdchar_mmap_capabilities(struct file *file)
1161{
1162 struct mtd_file_info *mfi = file->private_data;
1163
1164 return mtd_mmap_capabilities(mfi->mtd);
1165}
1166#endif
1167
1168/*
1169 * set up a mapping for shared memory segments
1170 */
1171static int mtdchar_mmap(struct file *file, struct vm_area_struct *vma)
1172{
1173#ifdef CONFIG_MMU
1174 struct mtd_file_info *mfi = file->private_data;
1175 struct mtd_info *mtd = mfi->mtd;
1176 struct map_info *map = mtd->priv;
1177
1178 /* This is broken because it assumes the MTD device is map-based
1179 and that mtd->priv is a valid struct map_info. It should be
1180 replaced with something that uses the mtd_get_unmapped_area()
1181 operation properly. */
1182 if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
1183#ifdef pgprot_noncached
1184 if (file->f_flags & O_DSYNC || map->phys >= __pa(high_memory))
1185 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1186#endif
1187 return vm_iomap_memory(vma, map->phys, map->size);
1188 }
1189 return -ENODEV;
1190#else
1191 return vma->vm_flags & VM_SHARED ? 0 : -EACCES;
1192#endif
1193}
1194
1195static const struct file_operations mtd_fops = {
1196 .owner = THIS_MODULE,
1197 .llseek = mtdchar_lseek,
1198 .read = mtdchar_read,
1199 .write = mtdchar_write,
1200 .unlocked_ioctl = mtdchar_unlocked_ioctl,
1201#ifdef CONFIG_COMPAT
1202 .compat_ioctl = mtdchar_compat_ioctl,
1203#endif
1204 .open = mtdchar_open,
1205 .release = mtdchar_close,
1206 .mmap = mtdchar_mmap,
1207#ifndef CONFIG_MMU
1208 .get_unmapped_area = mtdchar_get_unmapped_area,
1209 .mmap_capabilities = mtdchar_mmap_capabilities,
1210#endif
1211};
1212
1213int __init init_mtdchar(void)
1214{
1215 int ret;
1216
1217 ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1218 "mtd", &mtd_fops);
1219 if (ret < 0) {
1220 pr_err("Can't allocate major number %d for MTD\n",
1221 MTD_CHAR_MAJOR);
1222 return ret;
1223 }
1224
1225 return ret;
1226}
1227
1228void __exit cleanup_mtdchar(void)
1229{
1230 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1231}
1232
1233MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
4 */
5
6#include <linux/device.h>
7#include <linux/fs.h>
8#include <linux/mm.h>
9#include <linux/err.h>
10#include <linux/init.h>
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/sched.h>
15#include <linux/mutex.h>
16#include <linux/backing-dev.h>
17#include <linux/compat.h>
18#include <linux/mount.h>
19#include <linux/blkpg.h>
20#include <linux/magic.h>
21#include <linux/major.h>
22#include <linux/mtd/mtd.h>
23#include <linux/mtd/partitions.h>
24#include <linux/mtd/map.h>
25
26#include <linux/uaccess.h>
27
28#include "mtdcore.h"
29
30/*
31 * Data structure to hold the pointer to the mtd device as well
32 * as mode information of various use cases.
33 */
34struct mtd_file_info {
35 struct mtd_info *mtd;
36 enum mtd_file_modes mode;
37};
38
39static loff_t mtdchar_lseek(struct file *file, loff_t offset, int orig)
40{
41 struct mtd_file_info *mfi = file->private_data;
42 return fixed_size_llseek(file, offset, orig, mfi->mtd->size);
43}
44
45static int mtdchar_open(struct inode *inode, struct file *file)
46{
47 int minor = iminor(inode);
48 int devnum = minor >> 1;
49 int ret = 0;
50 struct mtd_info *mtd;
51 struct mtd_file_info *mfi;
52
53 pr_debug("MTD_open\n");
54
55 /* You can't open the RO devices RW */
56 if ((file->f_mode & FMODE_WRITE) && (minor & 1))
57 return -EACCES;
58
59 mtd = get_mtd_device(NULL, devnum);
60
61 if (IS_ERR(mtd))
62 return PTR_ERR(mtd);
63
64 if (mtd->type == MTD_ABSENT) {
65 ret = -ENODEV;
66 goto out1;
67 }
68
69 /* You can't open it RW if it's not a writeable device */
70 if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
71 ret = -EACCES;
72 goto out1;
73 }
74
75 mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
76 if (!mfi) {
77 ret = -ENOMEM;
78 goto out1;
79 }
80 mfi->mtd = mtd;
81 file->private_data = mfi;
82 return 0;
83
84out1:
85 put_mtd_device(mtd);
86 return ret;
87} /* mtdchar_open */
88
89/*====================================================================*/
90
91static int mtdchar_close(struct inode *inode, struct file *file)
92{
93 struct mtd_file_info *mfi = file->private_data;
94 struct mtd_info *mtd = mfi->mtd;
95
96 pr_debug("MTD_close\n");
97
98 /* Only sync if opened RW */
99 if ((file->f_mode & FMODE_WRITE))
100 mtd_sync(mtd);
101
102 put_mtd_device(mtd);
103 file->private_data = NULL;
104 kfree(mfi);
105
106 return 0;
107} /* mtdchar_close */
108
109/* Back in June 2001, dwmw2 wrote:
110 *
111 * FIXME: This _really_ needs to die. In 2.5, we should lock the
112 * userspace buffer down and use it directly with readv/writev.
113 *
114 * The implementation below, using mtd_kmalloc_up_to, mitigates
115 * allocation failures when the system is under low-memory situations
116 * or if memory is highly fragmented at the cost of reducing the
117 * performance of the requested transfer due to a smaller buffer size.
118 *
119 * A more complex but more memory-efficient implementation based on
120 * get_user_pages and iovecs to cover extents of those pages is a
121 * longer-term goal, as intimated by dwmw2 above. However, for the
122 * write case, this requires yet more complex head and tail transfer
123 * handling when those head and tail offsets and sizes are such that
124 * alignment requirements are not met in the NAND subdriver.
125 */
126
127static ssize_t mtdchar_read(struct file *file, char __user *buf, size_t count,
128 loff_t *ppos)
129{
130 struct mtd_file_info *mfi = file->private_data;
131 struct mtd_info *mtd = mfi->mtd;
132 size_t retlen;
133 size_t total_retlen=0;
134 int ret=0;
135 int len;
136 size_t size = count;
137 char *kbuf;
138
139 pr_debug("MTD_read\n");
140
141 if (*ppos + count > mtd->size) {
142 if (*ppos < mtd->size)
143 count = mtd->size - *ppos;
144 else
145 count = 0;
146 }
147
148 if (!count)
149 return 0;
150
151 kbuf = mtd_kmalloc_up_to(mtd, &size);
152 if (!kbuf)
153 return -ENOMEM;
154
155 while (count) {
156 len = min_t(size_t, count, size);
157
158 switch (mfi->mode) {
159 case MTD_FILE_MODE_OTP_FACTORY:
160 ret = mtd_read_fact_prot_reg(mtd, *ppos, len,
161 &retlen, kbuf);
162 break;
163 case MTD_FILE_MODE_OTP_USER:
164 ret = mtd_read_user_prot_reg(mtd, *ppos, len,
165 &retlen, kbuf);
166 break;
167 case MTD_FILE_MODE_RAW:
168 {
169 struct mtd_oob_ops ops = {};
170
171 ops.mode = MTD_OPS_RAW;
172 ops.datbuf = kbuf;
173 ops.oobbuf = NULL;
174 ops.len = len;
175
176 ret = mtd_read_oob(mtd, *ppos, &ops);
177 retlen = ops.retlen;
178 break;
179 }
180 default:
181 ret = mtd_read(mtd, *ppos, len, &retlen, kbuf);
182 }
183 /* Nand returns -EBADMSG on ECC errors, but it returns
184 * the data. For our userspace tools it is important
185 * to dump areas with ECC errors!
186 * For kernel internal usage it also might return -EUCLEAN
187 * to signal the caller that a bitflip has occurred and has
188 * been corrected by the ECC algorithm.
189 * Userspace software which accesses NAND this way
190 * must be aware of the fact that it deals with NAND
191 */
192 if (!ret || mtd_is_bitflip_or_eccerr(ret)) {
193 *ppos += retlen;
194 if (copy_to_user(buf, kbuf, retlen)) {
195 kfree(kbuf);
196 return -EFAULT;
197 }
198 else
199 total_retlen += retlen;
200
201 count -= retlen;
202 buf += retlen;
203 if (retlen == 0)
204 count = 0;
205 }
206 else {
207 kfree(kbuf);
208 return ret;
209 }
210
211 }
212
213 kfree(kbuf);
214 return total_retlen;
215} /* mtdchar_read */
216
217static ssize_t mtdchar_write(struct file *file, const char __user *buf, size_t count,
218 loff_t *ppos)
219{
220 struct mtd_file_info *mfi = file->private_data;
221 struct mtd_info *mtd = mfi->mtd;
222 size_t size = count;
223 char *kbuf;
224 size_t retlen;
225 size_t total_retlen=0;
226 int ret=0;
227 int len;
228
229 pr_debug("MTD_write\n");
230
231 if (*ppos >= mtd->size)
232 return -ENOSPC;
233
234 if (*ppos + count > mtd->size)
235 count = mtd->size - *ppos;
236
237 if (!count)
238 return 0;
239
240 kbuf = mtd_kmalloc_up_to(mtd, &size);
241 if (!kbuf)
242 return -ENOMEM;
243
244 while (count) {
245 len = min_t(size_t, count, size);
246
247 if (copy_from_user(kbuf, buf, len)) {
248 kfree(kbuf);
249 return -EFAULT;
250 }
251
252 switch (mfi->mode) {
253 case MTD_FILE_MODE_OTP_FACTORY:
254 ret = -EROFS;
255 break;
256 case MTD_FILE_MODE_OTP_USER:
257 ret = mtd_write_user_prot_reg(mtd, *ppos, len,
258 &retlen, kbuf);
259 break;
260
261 case MTD_FILE_MODE_RAW:
262 {
263 struct mtd_oob_ops ops = {};
264
265 ops.mode = MTD_OPS_RAW;
266 ops.datbuf = kbuf;
267 ops.oobbuf = NULL;
268 ops.ooboffs = 0;
269 ops.len = len;
270
271 ret = mtd_write_oob(mtd, *ppos, &ops);
272 retlen = ops.retlen;
273 break;
274 }
275
276 default:
277 ret = mtd_write(mtd, *ppos, len, &retlen, kbuf);
278 }
279
280 /*
281 * Return -ENOSPC only if no data could be written at all.
282 * Otherwise just return the number of bytes that actually
283 * have been written.
284 */
285 if ((ret == -ENOSPC) && (total_retlen))
286 break;
287
288 if (!ret) {
289 *ppos += retlen;
290 total_retlen += retlen;
291 count -= retlen;
292 buf += retlen;
293 }
294 else {
295 kfree(kbuf);
296 return ret;
297 }
298 }
299
300 kfree(kbuf);
301 return total_retlen;
302} /* mtdchar_write */
303
304/*======================================================================
305
306 IOCTL calls for getting device parameters.
307
308======================================================================*/
309
310static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
311{
312 struct mtd_info *mtd = mfi->mtd;
313 size_t retlen;
314
315 switch (mode) {
316 case MTD_OTP_FACTORY:
317 if (mtd_read_fact_prot_reg(mtd, -1, 0, &retlen, NULL) ==
318 -EOPNOTSUPP)
319 return -EOPNOTSUPP;
320
321 mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
322 break;
323 case MTD_OTP_USER:
324 if (mtd_read_user_prot_reg(mtd, -1, 0, &retlen, NULL) ==
325 -EOPNOTSUPP)
326 return -EOPNOTSUPP;
327
328 mfi->mode = MTD_FILE_MODE_OTP_USER;
329 break;
330 case MTD_OTP_OFF:
331 mfi->mode = MTD_FILE_MODE_NORMAL;
332 break;
333 default:
334 return -EINVAL;
335 }
336
337 return 0;
338}
339
340static int mtdchar_writeoob(struct file *file, struct mtd_info *mtd,
341 uint64_t start, uint32_t length, void __user *ptr,
342 uint32_t __user *retp)
343{
344 struct mtd_info *master = mtd_get_master(mtd);
345 struct mtd_file_info *mfi = file->private_data;
346 struct mtd_oob_ops ops = {};
347 uint32_t retlen;
348 int ret = 0;
349
350 if (length > 4096)
351 return -EINVAL;
352
353 if (!master->_write_oob)
354 return -EOPNOTSUPP;
355
356 ops.ooblen = length;
357 ops.ooboffs = start & (mtd->writesize - 1);
358 ops.datbuf = NULL;
359 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
360 MTD_OPS_PLACE_OOB;
361
362 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
363 return -EINVAL;
364
365 ops.oobbuf = memdup_user(ptr, length);
366 if (IS_ERR(ops.oobbuf))
367 return PTR_ERR(ops.oobbuf);
368
369 start &= ~((uint64_t)mtd->writesize - 1);
370 ret = mtd_write_oob(mtd, start, &ops);
371
372 if (ops.oobretlen > 0xFFFFFFFFU)
373 ret = -EOVERFLOW;
374 retlen = ops.oobretlen;
375 if (copy_to_user(retp, &retlen, sizeof(length)))
376 ret = -EFAULT;
377
378 kfree(ops.oobbuf);
379 return ret;
380}
381
382static int mtdchar_readoob(struct file *file, struct mtd_info *mtd,
383 uint64_t start, uint32_t length, void __user *ptr,
384 uint32_t __user *retp)
385{
386 struct mtd_file_info *mfi = file->private_data;
387 struct mtd_oob_ops ops = {};
388 int ret = 0;
389
390 if (length > 4096)
391 return -EINVAL;
392
393 ops.ooblen = length;
394 ops.ooboffs = start & (mtd->writesize - 1);
395 ops.datbuf = NULL;
396 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
397 MTD_OPS_PLACE_OOB;
398
399 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
400 return -EINVAL;
401
402 ops.oobbuf = kmalloc(length, GFP_KERNEL);
403 if (!ops.oobbuf)
404 return -ENOMEM;
405
406 start &= ~((uint64_t)mtd->writesize - 1);
407 ret = mtd_read_oob(mtd, start, &ops);
408
409 if (put_user(ops.oobretlen, retp))
410 ret = -EFAULT;
411 else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
412 ops.oobretlen))
413 ret = -EFAULT;
414
415 kfree(ops.oobbuf);
416
417 /*
418 * NAND returns -EBADMSG on ECC errors, but it returns the OOB
419 * data. For our userspace tools it is important to dump areas
420 * with ECC errors!
421 * For kernel internal usage it also might return -EUCLEAN
422 * to signal the caller that a bitflip has occurred and has
423 * been corrected by the ECC algorithm.
424 *
425 * Note: currently the standard NAND function, nand_read_oob_std,
426 * does not calculate ECC for the OOB area, so do not rely on
427 * this behavior unless you have replaced it with your own.
428 */
429 if (mtd_is_bitflip_or_eccerr(ret))
430 return 0;
431
432 return ret;
433}
434
435/*
436 * Copies (and truncates, if necessary) OOB layout information to the
437 * deprecated layout struct, nand_ecclayout_user. This is necessary only to
438 * support the deprecated API ioctl ECCGETLAYOUT while allowing all new
439 * functionality to use mtd_ooblayout_ops flexibly (i.e. mtd_ooblayout_ops
440 * can describe any kind of OOB layout with almost zero overhead from a
441 * memory usage point of view).
442 */
443static int shrink_ecclayout(struct mtd_info *mtd,
444 struct nand_ecclayout_user *to)
445{
446 struct mtd_oob_region oobregion;
447 int i, section = 0, ret;
448
449 if (!mtd || !to)
450 return -EINVAL;
451
452 memset(to, 0, sizeof(*to));
453
454 to->eccbytes = 0;
455 for (i = 0; i < MTD_MAX_ECCPOS_ENTRIES;) {
456 u32 eccpos;
457
458 ret = mtd_ooblayout_ecc(mtd, section++, &oobregion);
459 if (ret < 0) {
460 if (ret != -ERANGE)
461 return ret;
462
463 break;
464 }
465
466 eccpos = oobregion.offset;
467 for (; i < MTD_MAX_ECCPOS_ENTRIES &&
468 eccpos < oobregion.offset + oobregion.length; i++) {
469 to->eccpos[i] = eccpos++;
470 to->eccbytes++;
471 }
472 }
473
474 for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
475 ret = mtd_ooblayout_free(mtd, i, &oobregion);
476 if (ret < 0) {
477 if (ret != -ERANGE)
478 return ret;
479
480 break;
481 }
482
483 to->oobfree[i].offset = oobregion.offset;
484 to->oobfree[i].length = oobregion.length;
485 to->oobavail += to->oobfree[i].length;
486 }
487
488 return 0;
489}
490
491static int get_oobinfo(struct mtd_info *mtd, struct nand_oobinfo *to)
492{
493 struct mtd_oob_region oobregion;
494 int i, section = 0, ret;
495
496 if (!mtd || !to)
497 return -EINVAL;
498
499 memset(to, 0, sizeof(*to));
500
501 to->eccbytes = 0;
502 for (i = 0; i < ARRAY_SIZE(to->eccpos);) {
503 u32 eccpos;
504
505 ret = mtd_ooblayout_ecc(mtd, section++, &oobregion);
506 if (ret < 0) {
507 if (ret != -ERANGE)
508 return ret;
509
510 break;
511 }
512
513 if (oobregion.length + i > ARRAY_SIZE(to->eccpos))
514 return -EINVAL;
515
516 eccpos = oobregion.offset;
517 for (; eccpos < oobregion.offset + oobregion.length; i++) {
518 to->eccpos[i] = eccpos++;
519 to->eccbytes++;
520 }
521 }
522
523 for (i = 0; i < 8; i++) {
524 ret = mtd_ooblayout_free(mtd, i, &oobregion);
525 if (ret < 0) {
526 if (ret != -ERANGE)
527 return ret;
528
529 break;
530 }
531
532 to->oobfree[i][0] = oobregion.offset;
533 to->oobfree[i][1] = oobregion.length;
534 }
535
536 to->useecc = MTD_NANDECC_AUTOPLACE;
537
538 return 0;
539}
540
541static int mtdchar_blkpg_ioctl(struct mtd_info *mtd,
542 struct blkpg_ioctl_arg *arg)
543{
544 struct blkpg_partition p;
545
546 if (!capable(CAP_SYS_ADMIN))
547 return -EPERM;
548
549 if (copy_from_user(&p, arg->data, sizeof(p)))
550 return -EFAULT;
551
552 switch (arg->op) {
553 case BLKPG_ADD_PARTITION:
554
555 /* Only master mtd device must be used to add partitions */
556 if (mtd_is_partition(mtd))
557 return -EINVAL;
558
559 /* Sanitize user input */
560 p.devname[BLKPG_DEVNAMELTH - 1] = '\0';
561
562 return mtd_add_partition(mtd, p.devname, p.start, p.length);
563
564 case BLKPG_DEL_PARTITION:
565
566 if (p.pno < 0)
567 return -EINVAL;
568
569 return mtd_del_partition(mtd, p.pno);
570
571 default:
572 return -EINVAL;
573 }
574}
575
576static int mtdchar_write_ioctl(struct mtd_info *mtd,
577 struct mtd_write_req __user *argp)
578{
579 struct mtd_info *master = mtd_get_master(mtd);
580 struct mtd_write_req req;
581 struct mtd_oob_ops ops = {};
582 const void __user *usr_data, *usr_oob;
583 int ret;
584
585 if (copy_from_user(&req, argp, sizeof(req)))
586 return -EFAULT;
587
588 usr_data = (const void __user *)(uintptr_t)req.usr_data;
589 usr_oob = (const void __user *)(uintptr_t)req.usr_oob;
590
591 if (!master->_write_oob)
592 return -EOPNOTSUPP;
593 ops.mode = req.mode;
594 ops.len = (size_t)req.len;
595 ops.ooblen = (size_t)req.ooblen;
596 ops.ooboffs = 0;
597
598 if (usr_data) {
599 ops.datbuf = memdup_user(usr_data, ops.len);
600 if (IS_ERR(ops.datbuf))
601 return PTR_ERR(ops.datbuf);
602 } else {
603 ops.datbuf = NULL;
604 }
605
606 if (usr_oob) {
607 ops.oobbuf = memdup_user(usr_oob, ops.ooblen);
608 if (IS_ERR(ops.oobbuf)) {
609 kfree(ops.datbuf);
610 return PTR_ERR(ops.oobbuf);
611 }
612 } else {
613 ops.oobbuf = NULL;
614 }
615
616 ret = mtd_write_oob(mtd, (loff_t)req.start, &ops);
617
618 kfree(ops.datbuf);
619 kfree(ops.oobbuf);
620
621 return ret;
622}
623
624static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
625{
626 struct mtd_file_info *mfi = file->private_data;
627 struct mtd_info *mtd = mfi->mtd;
628 struct mtd_info *master = mtd_get_master(mtd);
629 void __user *argp = (void __user *)arg;
630 int ret = 0;
631 struct mtd_info_user info;
632
633 pr_debug("MTD_ioctl\n");
634
635 /*
636 * Check the file mode to require "dangerous" commands to have write
637 * permissions.
638 */
639 switch (cmd) {
640 /* "safe" commands */
641 case MEMGETREGIONCOUNT:
642 case MEMGETREGIONINFO:
643 case MEMGETINFO:
644 case MEMREADOOB:
645 case MEMREADOOB64:
646 case MEMISLOCKED:
647 case MEMGETOOBSEL:
648 case MEMGETBADBLOCK:
649 case OTPSELECT:
650 case OTPGETREGIONCOUNT:
651 case OTPGETREGIONINFO:
652 case ECCGETLAYOUT:
653 case ECCGETSTATS:
654 case MTDFILEMODE:
655 case BLKPG:
656 case BLKRRPART:
657 break;
658
659 /* "dangerous" commands */
660 case MEMERASE:
661 case MEMERASE64:
662 case MEMLOCK:
663 case MEMUNLOCK:
664 case MEMSETBADBLOCK:
665 case MEMWRITEOOB:
666 case MEMWRITEOOB64:
667 case MEMWRITE:
668 case OTPLOCK:
669 case OTPERASE:
670 if (!(file->f_mode & FMODE_WRITE))
671 return -EPERM;
672 break;
673
674 default:
675 return -ENOTTY;
676 }
677
678 switch (cmd) {
679 case MEMGETREGIONCOUNT:
680 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
681 return -EFAULT;
682 break;
683
684 case MEMGETREGIONINFO:
685 {
686 uint32_t ur_idx;
687 struct mtd_erase_region_info *kr;
688 struct region_info_user __user *ur = argp;
689
690 if (get_user(ur_idx, &(ur->regionindex)))
691 return -EFAULT;
692
693 if (ur_idx >= mtd->numeraseregions)
694 return -EINVAL;
695
696 kr = &(mtd->eraseregions[ur_idx]);
697
698 if (put_user(kr->offset, &(ur->offset))
699 || put_user(kr->erasesize, &(ur->erasesize))
700 || put_user(kr->numblocks, &(ur->numblocks)))
701 return -EFAULT;
702
703 break;
704 }
705
706 case MEMGETINFO:
707 memset(&info, 0, sizeof(info));
708 info.type = mtd->type;
709 info.flags = mtd->flags;
710 info.size = mtd->size;
711 info.erasesize = mtd->erasesize;
712 info.writesize = mtd->writesize;
713 info.oobsize = mtd->oobsize;
714 /* The below field is obsolete */
715 info.padding = 0;
716 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
717 return -EFAULT;
718 break;
719
720 case MEMERASE:
721 case MEMERASE64:
722 {
723 struct erase_info *erase;
724
725 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
726 if (!erase)
727 ret = -ENOMEM;
728 else {
729 if (cmd == MEMERASE64) {
730 struct erase_info_user64 einfo64;
731
732 if (copy_from_user(&einfo64, argp,
733 sizeof(struct erase_info_user64))) {
734 kfree(erase);
735 return -EFAULT;
736 }
737 erase->addr = einfo64.start;
738 erase->len = einfo64.length;
739 } else {
740 struct erase_info_user einfo32;
741
742 if (copy_from_user(&einfo32, argp,
743 sizeof(struct erase_info_user))) {
744 kfree(erase);
745 return -EFAULT;
746 }
747 erase->addr = einfo32.start;
748 erase->len = einfo32.length;
749 }
750
751 ret = mtd_erase(mtd, erase);
752 kfree(erase);
753 }
754 break;
755 }
756
757 case MEMWRITEOOB:
758 {
759 struct mtd_oob_buf buf;
760 struct mtd_oob_buf __user *buf_user = argp;
761
762 /* NOTE: writes return length to buf_user->length */
763 if (copy_from_user(&buf, argp, sizeof(buf)))
764 ret = -EFAULT;
765 else
766 ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
767 buf.ptr, &buf_user->length);
768 break;
769 }
770
771 case MEMREADOOB:
772 {
773 struct mtd_oob_buf buf;
774 struct mtd_oob_buf __user *buf_user = argp;
775
776 /* NOTE: writes return length to buf_user->start */
777 if (copy_from_user(&buf, argp, sizeof(buf)))
778 ret = -EFAULT;
779 else
780 ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
781 buf.ptr, &buf_user->start);
782 break;
783 }
784
785 case MEMWRITEOOB64:
786 {
787 struct mtd_oob_buf64 buf;
788 struct mtd_oob_buf64 __user *buf_user = argp;
789
790 if (copy_from_user(&buf, argp, sizeof(buf)))
791 ret = -EFAULT;
792 else
793 ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
794 (void __user *)(uintptr_t)buf.usr_ptr,
795 &buf_user->length);
796 break;
797 }
798
799 case MEMREADOOB64:
800 {
801 struct mtd_oob_buf64 buf;
802 struct mtd_oob_buf64 __user *buf_user = argp;
803
804 if (copy_from_user(&buf, argp, sizeof(buf)))
805 ret = -EFAULT;
806 else
807 ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
808 (void __user *)(uintptr_t)buf.usr_ptr,
809 &buf_user->length);
810 break;
811 }
812
813 case MEMWRITE:
814 {
815 ret = mtdchar_write_ioctl(mtd,
816 (struct mtd_write_req __user *)arg);
817 break;
818 }
819
820 case MEMLOCK:
821 {
822 struct erase_info_user einfo;
823
824 if (copy_from_user(&einfo, argp, sizeof(einfo)))
825 return -EFAULT;
826
827 ret = mtd_lock(mtd, einfo.start, einfo.length);
828 break;
829 }
830
831 case MEMUNLOCK:
832 {
833 struct erase_info_user einfo;
834
835 if (copy_from_user(&einfo, argp, sizeof(einfo)))
836 return -EFAULT;
837
838 ret = mtd_unlock(mtd, einfo.start, einfo.length);
839 break;
840 }
841
842 case MEMISLOCKED:
843 {
844 struct erase_info_user einfo;
845
846 if (copy_from_user(&einfo, argp, sizeof(einfo)))
847 return -EFAULT;
848
849 ret = mtd_is_locked(mtd, einfo.start, einfo.length);
850 break;
851 }
852
853 /* Legacy interface */
854 case MEMGETOOBSEL:
855 {
856 struct nand_oobinfo oi;
857
858 if (!master->ooblayout)
859 return -EOPNOTSUPP;
860
861 ret = get_oobinfo(mtd, &oi);
862 if (ret)
863 return ret;
864
865 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
866 return -EFAULT;
867 break;
868 }
869
870 case MEMGETBADBLOCK:
871 {
872 loff_t offs;
873
874 if (copy_from_user(&offs, argp, sizeof(loff_t)))
875 return -EFAULT;
876 return mtd_block_isbad(mtd, offs);
877 }
878
879 case MEMSETBADBLOCK:
880 {
881 loff_t offs;
882
883 if (copy_from_user(&offs, argp, sizeof(loff_t)))
884 return -EFAULT;
885 return mtd_block_markbad(mtd, offs);
886 }
887
888 case OTPSELECT:
889 {
890 int mode;
891 if (copy_from_user(&mode, argp, sizeof(int)))
892 return -EFAULT;
893
894 mfi->mode = MTD_FILE_MODE_NORMAL;
895
896 ret = otp_select_filemode(mfi, mode);
897
898 file->f_pos = 0;
899 break;
900 }
901
902 case OTPGETREGIONCOUNT:
903 case OTPGETREGIONINFO:
904 {
905 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
906 size_t retlen;
907 if (!buf)
908 return -ENOMEM;
909 switch (mfi->mode) {
910 case MTD_FILE_MODE_OTP_FACTORY:
911 ret = mtd_get_fact_prot_info(mtd, 4096, &retlen, buf);
912 break;
913 case MTD_FILE_MODE_OTP_USER:
914 ret = mtd_get_user_prot_info(mtd, 4096, &retlen, buf);
915 break;
916 default:
917 ret = -EINVAL;
918 break;
919 }
920 if (!ret) {
921 if (cmd == OTPGETREGIONCOUNT) {
922 int nbr = retlen / sizeof(struct otp_info);
923 ret = copy_to_user(argp, &nbr, sizeof(int));
924 } else
925 ret = copy_to_user(argp, buf, retlen);
926 if (ret)
927 ret = -EFAULT;
928 }
929 kfree(buf);
930 break;
931 }
932
933 case OTPLOCK:
934 case OTPERASE:
935 {
936 struct otp_info oinfo;
937
938 if (mfi->mode != MTD_FILE_MODE_OTP_USER)
939 return -EINVAL;
940 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
941 return -EFAULT;
942 if (cmd == OTPLOCK)
943 ret = mtd_lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
944 else
945 ret = mtd_erase_user_prot_reg(mtd, oinfo.start, oinfo.length);
946 break;
947 }
948
949 /* This ioctl is being deprecated - it truncates the ECC layout */
950 case ECCGETLAYOUT:
951 {
952 struct nand_ecclayout_user *usrlay;
953
954 if (!master->ooblayout)
955 return -EOPNOTSUPP;
956
957 usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
958 if (!usrlay)
959 return -ENOMEM;
960
961 shrink_ecclayout(mtd, usrlay);
962
963 if (copy_to_user(argp, usrlay, sizeof(*usrlay)))
964 ret = -EFAULT;
965 kfree(usrlay);
966 break;
967 }
968
969 case ECCGETSTATS:
970 {
971 if (copy_to_user(argp, &mtd->ecc_stats,
972 sizeof(struct mtd_ecc_stats)))
973 return -EFAULT;
974 break;
975 }
976
977 case MTDFILEMODE:
978 {
979 mfi->mode = 0;
980
981 switch(arg) {
982 case MTD_FILE_MODE_OTP_FACTORY:
983 case MTD_FILE_MODE_OTP_USER:
984 ret = otp_select_filemode(mfi, arg);
985 break;
986
987 case MTD_FILE_MODE_RAW:
988 if (!mtd_has_oob(mtd))
989 return -EOPNOTSUPP;
990 mfi->mode = arg;
991 break;
992
993 case MTD_FILE_MODE_NORMAL:
994 break;
995 default:
996 ret = -EINVAL;
997 }
998 file->f_pos = 0;
999 break;
1000 }
1001
1002 case BLKPG:
1003 {
1004 struct blkpg_ioctl_arg __user *blk_arg = argp;
1005 struct blkpg_ioctl_arg a;
1006
1007 if (copy_from_user(&a, blk_arg, sizeof(a)))
1008 ret = -EFAULT;
1009 else
1010 ret = mtdchar_blkpg_ioctl(mtd, &a);
1011 break;
1012 }
1013
1014 case BLKRRPART:
1015 {
1016 /* No reread partition feature. Just return ok */
1017 ret = 0;
1018 break;
1019 }
1020 }
1021
1022 return ret;
1023} /* memory_ioctl */
1024
1025static long mtdchar_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
1026{
1027 struct mtd_file_info *mfi = file->private_data;
1028 struct mtd_info *mtd = mfi->mtd;
1029 struct mtd_info *master = mtd_get_master(mtd);
1030 int ret;
1031
1032 mutex_lock(&master->master.chrdev_lock);
1033 ret = mtdchar_ioctl(file, cmd, arg);
1034 mutex_unlock(&master->master.chrdev_lock);
1035
1036 return ret;
1037}
1038
1039#ifdef CONFIG_COMPAT
1040
1041struct mtd_oob_buf32 {
1042 u_int32_t start;
1043 u_int32_t length;
1044 compat_caddr_t ptr; /* unsigned char* */
1045};
1046
1047#define MEMWRITEOOB32 _IOWR('M', 3, struct mtd_oob_buf32)
1048#define MEMREADOOB32 _IOWR('M', 4, struct mtd_oob_buf32)
1049
1050static long mtdchar_compat_ioctl(struct file *file, unsigned int cmd,
1051 unsigned long arg)
1052{
1053 struct mtd_file_info *mfi = file->private_data;
1054 struct mtd_info *mtd = mfi->mtd;
1055 struct mtd_info *master = mtd_get_master(mtd);
1056 void __user *argp = compat_ptr(arg);
1057 int ret = 0;
1058
1059 mutex_lock(&master->master.chrdev_lock);
1060
1061 switch (cmd) {
1062 case MEMWRITEOOB32:
1063 {
1064 struct mtd_oob_buf32 buf;
1065 struct mtd_oob_buf32 __user *buf_user = argp;
1066
1067 if (!(file->f_mode & FMODE_WRITE)) {
1068 ret = -EPERM;
1069 break;
1070 }
1071
1072 if (copy_from_user(&buf, argp, sizeof(buf)))
1073 ret = -EFAULT;
1074 else
1075 ret = mtdchar_writeoob(file, mtd, buf.start,
1076 buf.length, compat_ptr(buf.ptr),
1077 &buf_user->length);
1078 break;
1079 }
1080
1081 case MEMREADOOB32:
1082 {
1083 struct mtd_oob_buf32 buf;
1084 struct mtd_oob_buf32 __user *buf_user = argp;
1085
1086 /* NOTE: writes return length to buf->start */
1087 if (copy_from_user(&buf, argp, sizeof(buf)))
1088 ret = -EFAULT;
1089 else
1090 ret = mtdchar_readoob(file, mtd, buf.start,
1091 buf.length, compat_ptr(buf.ptr),
1092 &buf_user->start);
1093 break;
1094 }
1095
1096 case BLKPG:
1097 {
1098 /* Convert from blkpg_compat_ioctl_arg to blkpg_ioctl_arg */
1099 struct blkpg_compat_ioctl_arg __user *uarg = argp;
1100 struct blkpg_compat_ioctl_arg compat_arg;
1101 struct blkpg_ioctl_arg a;
1102
1103 if (copy_from_user(&compat_arg, uarg, sizeof(compat_arg))) {
1104 ret = -EFAULT;
1105 break;
1106 }
1107
1108 memset(&a, 0, sizeof(a));
1109 a.op = compat_arg.op;
1110 a.flags = compat_arg.flags;
1111 a.datalen = compat_arg.datalen;
1112 a.data = compat_ptr(compat_arg.data);
1113
1114 ret = mtdchar_blkpg_ioctl(mtd, &a);
1115 break;
1116 }
1117
1118 default:
1119 ret = mtdchar_ioctl(file, cmd, (unsigned long)argp);
1120 }
1121
1122 mutex_unlock(&master->master.chrdev_lock);
1123
1124 return ret;
1125}
1126
1127#endif /* CONFIG_COMPAT */
1128
1129/*
1130 * try to determine where a shared mapping can be made
1131 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
1132 * mappings)
1133 */
1134#ifndef CONFIG_MMU
1135static unsigned long mtdchar_get_unmapped_area(struct file *file,
1136 unsigned long addr,
1137 unsigned long len,
1138 unsigned long pgoff,
1139 unsigned long flags)
1140{
1141 struct mtd_file_info *mfi = file->private_data;
1142 struct mtd_info *mtd = mfi->mtd;
1143 unsigned long offset;
1144 int ret;
1145
1146 if (addr != 0)
1147 return (unsigned long) -EINVAL;
1148
1149 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
1150 return (unsigned long) -EINVAL;
1151
1152 offset = pgoff << PAGE_SHIFT;
1153 if (offset > mtd->size - len)
1154 return (unsigned long) -EINVAL;
1155
1156 ret = mtd_get_unmapped_area(mtd, len, offset, flags);
1157 return ret == -EOPNOTSUPP ? -ENODEV : ret;
1158}
1159
1160static unsigned mtdchar_mmap_capabilities(struct file *file)
1161{
1162 struct mtd_file_info *mfi = file->private_data;
1163
1164 return mtd_mmap_capabilities(mfi->mtd);
1165}
1166#endif
1167
1168/*
1169 * set up a mapping for shared memory segments
1170 */
1171static int mtdchar_mmap(struct file *file, struct vm_area_struct *vma)
1172{
1173#ifdef CONFIG_MMU
1174 struct mtd_file_info *mfi = file->private_data;
1175 struct mtd_info *mtd = mfi->mtd;
1176 struct map_info *map = mtd->priv;
1177
1178 /* This is broken because it assumes the MTD device is map-based
1179 and that mtd->priv is a valid struct map_info. It should be
1180 replaced with something that uses the mtd_get_unmapped_area()
1181 operation properly. */
1182 if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
1183#ifdef pgprot_noncached
1184 if (file->f_flags & O_DSYNC || map->phys >= __pa(high_memory))
1185 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1186#endif
1187 return vm_iomap_memory(vma, map->phys, map->size);
1188 }
1189 return -ENODEV;
1190#else
1191 return vma->vm_flags & VM_SHARED ? 0 : -EACCES;
1192#endif
1193}
1194
1195static const struct file_operations mtd_fops = {
1196 .owner = THIS_MODULE,
1197 .llseek = mtdchar_lseek,
1198 .read = mtdchar_read,
1199 .write = mtdchar_write,
1200 .unlocked_ioctl = mtdchar_unlocked_ioctl,
1201#ifdef CONFIG_COMPAT
1202 .compat_ioctl = mtdchar_compat_ioctl,
1203#endif
1204 .open = mtdchar_open,
1205 .release = mtdchar_close,
1206 .mmap = mtdchar_mmap,
1207#ifndef CONFIG_MMU
1208 .get_unmapped_area = mtdchar_get_unmapped_area,
1209 .mmap_capabilities = mtdchar_mmap_capabilities,
1210#endif
1211};
1212
1213int __init init_mtdchar(void)
1214{
1215 int ret;
1216
1217 ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1218 "mtd", &mtd_fops);
1219 if (ret < 0) {
1220 pr_err("Can't allocate major number %d for MTD\n",
1221 MTD_CHAR_MAJOR);
1222 return ret;
1223 }
1224
1225 return ret;
1226}
1227
1228void __exit cleanup_mtdchar(void)
1229{
1230 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1231}
1232
1233MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);