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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/*
2 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 *
18 */
19
20#include <linux/device.h>
21#include <linux/fs.h>
22#include <linux/mm.h>
23#include <linux/err.h>
24#include <linux/init.h>
25#include <linux/kernel.h>
26#include <linux/module.h>
27#include <linux/slab.h>
28#include <linux/sched.h>
29#include <linux/mutex.h>
30#include <linux/backing-dev.h>
31#include <linux/compat.h>
32#include <linux/mount.h>
33#include <linux/blkpg.h>
34#include <linux/magic.h>
35#include <linux/mtd/mtd.h>
36#include <linux/mtd/partitions.h>
37#include <linux/mtd/map.h>
38
39#include <asm/uaccess.h>
40
41static DEFINE_MUTEX(mtd_mutex);
42
43/*
44 * Data structure to hold the pointer to the mtd device as well
45 * as mode information of various use cases.
46 */
47struct mtd_file_info {
48 struct mtd_info *mtd;
49 struct inode *ino;
50 enum mtd_file_modes mode;
51};
52
53static loff_t mtdchar_lseek(struct file *file, loff_t offset, int orig)
54{
55 struct mtd_file_info *mfi = file->private_data;
56 struct mtd_info *mtd = mfi->mtd;
57
58 switch (orig) {
59 case SEEK_SET:
60 break;
61 case SEEK_CUR:
62 offset += file->f_pos;
63 break;
64 case SEEK_END:
65 offset += mtd->size;
66 break;
67 default:
68 return -EINVAL;
69 }
70
71 if (offset >= 0 && offset <= mtd->size)
72 return file->f_pos = offset;
73
74 return -EINVAL;
75}
76
77static int count;
78static struct vfsmount *mnt;
79static struct file_system_type mtd_inodefs_type;
80
81static int mtdchar_open(struct inode *inode, struct file *file)
82{
83 int minor = iminor(inode);
84 int devnum = minor >> 1;
85 int ret = 0;
86 struct mtd_info *mtd;
87 struct mtd_file_info *mfi;
88 struct inode *mtd_ino;
89
90 pr_debug("MTD_open\n");
91
92 /* You can't open the RO devices RW */
93 if ((file->f_mode & FMODE_WRITE) && (minor & 1))
94 return -EACCES;
95
96 ret = simple_pin_fs(&mtd_inodefs_type, &mnt, &count);
97 if (ret)
98 return ret;
99
100 mutex_lock(&mtd_mutex);
101 mtd = get_mtd_device(NULL, devnum);
102
103 if (IS_ERR(mtd)) {
104 ret = PTR_ERR(mtd);
105 goto out;
106 }
107
108 if (mtd->type == MTD_ABSENT) {
109 ret = -ENODEV;
110 goto out1;
111 }
112
113 mtd_ino = iget_locked(mnt->mnt_sb, devnum);
114 if (!mtd_ino) {
115 ret = -ENOMEM;
116 goto out1;
117 }
118 if (mtd_ino->i_state & I_NEW) {
119 mtd_ino->i_private = mtd;
120 mtd_ino->i_mode = S_IFCHR;
121 mtd_ino->i_data.backing_dev_info = mtd->backing_dev_info;
122 unlock_new_inode(mtd_ino);
123 }
124 file->f_mapping = mtd_ino->i_mapping;
125
126 /* You can't open it RW if it's not a writeable device */
127 if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
128 ret = -EACCES;
129 goto out2;
130 }
131
132 mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
133 if (!mfi) {
134 ret = -ENOMEM;
135 goto out2;
136 }
137 mfi->ino = mtd_ino;
138 mfi->mtd = mtd;
139 file->private_data = mfi;
140 mutex_unlock(&mtd_mutex);
141 return 0;
142
143out2:
144 iput(mtd_ino);
145out1:
146 put_mtd_device(mtd);
147out:
148 mutex_unlock(&mtd_mutex);
149 simple_release_fs(&mnt, &count);
150 return ret;
151} /* mtdchar_open */
152
153/*====================================================================*/
154
155static int mtdchar_close(struct inode *inode, struct file *file)
156{
157 struct mtd_file_info *mfi = file->private_data;
158 struct mtd_info *mtd = mfi->mtd;
159
160 pr_debug("MTD_close\n");
161
162 /* Only sync if opened RW */
163 if ((file->f_mode & FMODE_WRITE))
164 mtd_sync(mtd);
165
166 iput(mfi->ino);
167
168 put_mtd_device(mtd);
169 file->private_data = NULL;
170 kfree(mfi);
171 simple_release_fs(&mnt, &count);
172
173 return 0;
174} /* mtdchar_close */
175
176/* Back in June 2001, dwmw2 wrote:
177 *
178 * FIXME: This _really_ needs to die. In 2.5, we should lock the
179 * userspace buffer down and use it directly with readv/writev.
180 *
181 * The implementation below, using mtd_kmalloc_up_to, mitigates
182 * allocation failures when the system is under low-memory situations
183 * or if memory is highly fragmented at the cost of reducing the
184 * performance of the requested transfer due to a smaller buffer size.
185 *
186 * A more complex but more memory-efficient implementation based on
187 * get_user_pages and iovecs to cover extents of those pages is a
188 * longer-term goal, as intimated by dwmw2 above. However, for the
189 * write case, this requires yet more complex head and tail transfer
190 * handling when those head and tail offsets and sizes are such that
191 * alignment requirements are not met in the NAND subdriver.
192 */
193
194static ssize_t mtdchar_read(struct file *file, char __user *buf, size_t count,
195 loff_t *ppos)
196{
197 struct mtd_file_info *mfi = file->private_data;
198 struct mtd_info *mtd = mfi->mtd;
199 size_t retlen;
200 size_t total_retlen=0;
201 int ret=0;
202 int len;
203 size_t size = count;
204 char *kbuf;
205
206 pr_debug("MTD_read\n");
207
208 if (*ppos + count > mtd->size)
209 count = mtd->size - *ppos;
210
211 if (!count)
212 return 0;
213
214 kbuf = mtd_kmalloc_up_to(mtd, &size);
215 if (!kbuf)
216 return -ENOMEM;
217
218 while (count) {
219 len = min_t(size_t, count, size);
220
221 switch (mfi->mode) {
222 case MTD_FILE_MODE_OTP_FACTORY:
223 ret = mtd_read_fact_prot_reg(mtd, *ppos, len,
224 &retlen, kbuf);
225 break;
226 case MTD_FILE_MODE_OTP_USER:
227 ret = mtd_read_user_prot_reg(mtd, *ppos, len,
228 &retlen, kbuf);
229 break;
230 case MTD_FILE_MODE_RAW:
231 {
232 struct mtd_oob_ops ops;
233
234 ops.mode = MTD_OPS_RAW;
235 ops.datbuf = kbuf;
236 ops.oobbuf = NULL;
237 ops.len = len;
238
239 ret = mtd_read_oob(mtd, *ppos, &ops);
240 retlen = ops.retlen;
241 break;
242 }
243 default:
244 ret = mtd_read(mtd, *ppos, len, &retlen, kbuf);
245 }
246 /* Nand returns -EBADMSG on ECC errors, but it returns
247 * the data. For our userspace tools it is important
248 * to dump areas with ECC errors!
249 * For kernel internal usage it also might return -EUCLEAN
250 * to signal the caller that a bitflip has occurred and has
251 * been corrected by the ECC algorithm.
252 * Userspace software which accesses NAND this way
253 * must be aware of the fact that it deals with NAND
254 */
255 if (!ret || mtd_is_bitflip_or_eccerr(ret)) {
256 *ppos += retlen;
257 if (copy_to_user(buf, kbuf, retlen)) {
258 kfree(kbuf);
259 return -EFAULT;
260 }
261 else
262 total_retlen += retlen;
263
264 count -= retlen;
265 buf += retlen;
266 if (retlen == 0)
267 count = 0;
268 }
269 else {
270 kfree(kbuf);
271 return ret;
272 }
273
274 }
275
276 kfree(kbuf);
277 return total_retlen;
278} /* mtdchar_read */
279
280static ssize_t mtdchar_write(struct file *file, const char __user *buf, size_t count,
281 loff_t *ppos)
282{
283 struct mtd_file_info *mfi = file->private_data;
284 struct mtd_info *mtd = mfi->mtd;
285 size_t size = count;
286 char *kbuf;
287 size_t retlen;
288 size_t total_retlen=0;
289 int ret=0;
290 int len;
291
292 pr_debug("MTD_write\n");
293
294 if (*ppos == mtd->size)
295 return -ENOSPC;
296
297 if (*ppos + count > mtd->size)
298 count = mtd->size - *ppos;
299
300 if (!count)
301 return 0;
302
303 kbuf = mtd_kmalloc_up_to(mtd, &size);
304 if (!kbuf)
305 return -ENOMEM;
306
307 while (count) {
308 len = min_t(size_t, count, size);
309
310 if (copy_from_user(kbuf, buf, len)) {
311 kfree(kbuf);
312 return -EFAULT;
313 }
314
315 switch (mfi->mode) {
316 case MTD_FILE_MODE_OTP_FACTORY:
317 ret = -EROFS;
318 break;
319 case MTD_FILE_MODE_OTP_USER:
320 ret = mtd_write_user_prot_reg(mtd, *ppos, len,
321 &retlen, kbuf);
322 break;
323
324 case MTD_FILE_MODE_RAW:
325 {
326 struct mtd_oob_ops ops;
327
328 ops.mode = MTD_OPS_RAW;
329 ops.datbuf = kbuf;
330 ops.oobbuf = NULL;
331 ops.ooboffs = 0;
332 ops.len = len;
333
334 ret = mtd_write_oob(mtd, *ppos, &ops);
335 retlen = ops.retlen;
336 break;
337 }
338
339 default:
340 ret = mtd_write(mtd, *ppos, len, &retlen, kbuf);
341 }
342 if (!ret) {
343 *ppos += retlen;
344 total_retlen += retlen;
345 count -= retlen;
346 buf += retlen;
347 }
348 else {
349 kfree(kbuf);
350 return ret;
351 }
352 }
353
354 kfree(kbuf);
355 return total_retlen;
356} /* mtdchar_write */
357
358/*======================================================================
359
360 IOCTL calls for getting device parameters.
361
362======================================================================*/
363static void mtdchar_erase_callback (struct erase_info *instr)
364{
365 wake_up((wait_queue_head_t *)instr->priv);
366}
367
368#ifdef CONFIG_HAVE_MTD_OTP
369static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
370{
371 struct mtd_info *mtd = mfi->mtd;
372 size_t retlen;
373 int ret = 0;
374
375 /*
376 * Make a fake call to mtd_read_fact_prot_reg() to check if OTP
377 * operations are supported.
378 */
379 if (mtd_read_fact_prot_reg(mtd, -1, 0, &retlen, NULL) == -EOPNOTSUPP)
380 return -EOPNOTSUPP;
381
382 switch (mode) {
383 case MTD_OTP_FACTORY:
384 mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
385 break;
386 case MTD_OTP_USER:
387 mfi->mode = MTD_FILE_MODE_OTP_USER;
388 break;
389 default:
390 ret = -EINVAL;
391 case MTD_OTP_OFF:
392 break;
393 }
394 return ret;
395}
396#else
397# define otp_select_filemode(f,m) -EOPNOTSUPP
398#endif
399
400static int mtdchar_writeoob(struct file *file, struct mtd_info *mtd,
401 uint64_t start, uint32_t length, void __user *ptr,
402 uint32_t __user *retp)
403{
404 struct mtd_file_info *mfi = file->private_data;
405 struct mtd_oob_ops ops;
406 uint32_t retlen;
407 int ret = 0;
408
409 if (!(file->f_mode & FMODE_WRITE))
410 return -EPERM;
411
412 if (length > 4096)
413 return -EINVAL;
414
415 if (!mtd->_write_oob)
416 ret = -EOPNOTSUPP;
417 else
418 ret = access_ok(VERIFY_READ, ptr, length) ? 0 : -EFAULT;
419
420 if (ret)
421 return ret;
422
423 ops.ooblen = length;
424 ops.ooboffs = start & (mtd->writesize - 1);
425 ops.datbuf = NULL;
426 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
427 MTD_OPS_PLACE_OOB;
428
429 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
430 return -EINVAL;
431
432 ops.oobbuf = memdup_user(ptr, length);
433 if (IS_ERR(ops.oobbuf))
434 return PTR_ERR(ops.oobbuf);
435
436 start &= ~((uint64_t)mtd->writesize - 1);
437 ret = mtd_write_oob(mtd, start, &ops);
438
439 if (ops.oobretlen > 0xFFFFFFFFU)
440 ret = -EOVERFLOW;
441 retlen = ops.oobretlen;
442 if (copy_to_user(retp, &retlen, sizeof(length)))
443 ret = -EFAULT;
444
445 kfree(ops.oobbuf);
446 return ret;
447}
448
449static int mtdchar_readoob(struct file *file, struct mtd_info *mtd,
450 uint64_t start, uint32_t length, void __user *ptr,
451 uint32_t __user *retp)
452{
453 struct mtd_file_info *mfi = file->private_data;
454 struct mtd_oob_ops ops;
455 int ret = 0;
456
457 if (length > 4096)
458 return -EINVAL;
459
460 if (!access_ok(VERIFY_WRITE, ptr, length))
461 return -EFAULT;
462
463 ops.ooblen = length;
464 ops.ooboffs = start & (mtd->writesize - 1);
465 ops.datbuf = NULL;
466 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
467 MTD_OPS_PLACE_OOB;
468
469 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
470 return -EINVAL;
471
472 ops.oobbuf = kmalloc(length, GFP_KERNEL);
473 if (!ops.oobbuf)
474 return -ENOMEM;
475
476 start &= ~((uint64_t)mtd->writesize - 1);
477 ret = mtd_read_oob(mtd, start, &ops);
478
479 if (put_user(ops.oobretlen, retp))
480 ret = -EFAULT;
481 else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
482 ops.oobretlen))
483 ret = -EFAULT;
484
485 kfree(ops.oobbuf);
486
487 /*
488 * NAND returns -EBADMSG on ECC errors, but it returns the OOB
489 * data. For our userspace tools it is important to dump areas
490 * with ECC errors!
491 * For kernel internal usage it also might return -EUCLEAN
492 * to signal the caller that a bitflip has occured and has
493 * been corrected by the ECC algorithm.
494 *
495 * Note: currently the standard NAND function, nand_read_oob_std,
496 * does not calculate ECC for the OOB area, so do not rely on
497 * this behavior unless you have replaced it with your own.
498 */
499 if (mtd_is_bitflip_or_eccerr(ret))
500 return 0;
501
502 return ret;
503}
504
505/*
506 * Copies (and truncates, if necessary) data from the larger struct,
507 * nand_ecclayout, to the smaller, deprecated layout struct,
508 * nand_ecclayout_user. This is necessary only to support the deprecated
509 * API ioctl ECCGETLAYOUT while allowing all new functionality to use
510 * nand_ecclayout flexibly (i.e. the struct may change size in new
511 * releases without requiring major rewrites).
512 */
513static int shrink_ecclayout(const struct nand_ecclayout *from,
514 struct nand_ecclayout_user *to)
515{
516 int i;
517
518 if (!from || !to)
519 return -EINVAL;
520
521 memset(to, 0, sizeof(*to));
522
523 to->eccbytes = min((int)from->eccbytes, MTD_MAX_ECCPOS_ENTRIES);
524 for (i = 0; i < to->eccbytes; i++)
525 to->eccpos[i] = from->eccpos[i];
526
527 for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
528 if (from->oobfree[i].length == 0 &&
529 from->oobfree[i].offset == 0)
530 break;
531 to->oobavail += from->oobfree[i].length;
532 to->oobfree[i] = from->oobfree[i];
533 }
534
535 return 0;
536}
537
538static int mtdchar_blkpg_ioctl(struct mtd_info *mtd,
539 struct blkpg_ioctl_arg __user *arg)
540{
541 struct blkpg_ioctl_arg a;
542 struct blkpg_partition p;
543
544 if (!capable(CAP_SYS_ADMIN))
545 return -EPERM;
546
547 if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
548 return -EFAULT;
549
550 if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
551 return -EFAULT;
552
553 switch (a.op) {
554 case BLKPG_ADD_PARTITION:
555
556 /* Only master mtd device must be used to add partitions */
557 if (mtd_is_partition(mtd))
558 return -EINVAL;
559
560 return mtd_add_partition(mtd, p.devname, p.start, p.length);
561
562 case BLKPG_DEL_PARTITION:
563
564 if (p.pno < 0)
565 return -EINVAL;
566
567 return mtd_del_partition(mtd, p.pno);
568
569 default:
570 return -EINVAL;
571 }
572}
573
574static int mtdchar_write_ioctl(struct mtd_info *mtd,
575 struct mtd_write_req __user *argp)
576{
577 struct mtd_write_req req;
578 struct mtd_oob_ops ops;
579 void __user *usr_data, *usr_oob;
580 int ret;
581
582 if (copy_from_user(&req, argp, sizeof(req)) ||
583 !access_ok(VERIFY_READ, req.usr_data, req.len) ||
584 !access_ok(VERIFY_READ, req.usr_oob, req.ooblen))
585 return -EFAULT;
586 if (!mtd->_write_oob)
587 return -EOPNOTSUPP;
588
589 ops.mode = req.mode;
590 ops.len = (size_t)req.len;
591 ops.ooblen = (size_t)req.ooblen;
592 ops.ooboffs = 0;
593
594 usr_data = (void __user *)(uintptr_t)req.usr_data;
595 usr_oob = (void __user *)(uintptr_t)req.usr_oob;
596
597 if (req.usr_data) {
598 ops.datbuf = memdup_user(usr_data, ops.len);
599 if (IS_ERR(ops.datbuf))
600 return PTR_ERR(ops.datbuf);
601 } else {
602 ops.datbuf = NULL;
603 }
604
605 if (req.usr_oob) {
606 ops.oobbuf = memdup_user(usr_oob, ops.ooblen);
607 if (IS_ERR(ops.oobbuf)) {
608 kfree(ops.datbuf);
609 return PTR_ERR(ops.oobbuf);
610 }
611 } else {
612 ops.oobbuf = NULL;
613 }
614
615 ret = mtd_write_oob(mtd, (loff_t)req.start, &ops);
616
617 kfree(ops.datbuf);
618 kfree(ops.oobbuf);
619
620 return ret;
621}
622
623static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
624{
625 struct mtd_file_info *mfi = file->private_data;
626 struct mtd_info *mtd = mfi->mtd;
627 void __user *argp = (void __user *)arg;
628 int ret = 0;
629 u_long size;
630 struct mtd_info_user info;
631
632 pr_debug("MTD_ioctl\n");
633
634 size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
635 if (cmd & IOC_IN) {
636 if (!access_ok(VERIFY_READ, argp, size))
637 return -EFAULT;
638 }
639 if (cmd & IOC_OUT) {
640 if (!access_ok(VERIFY_WRITE, argp, size))
641 return -EFAULT;
642 }
643
644 switch (cmd) {
645 case MEMGETREGIONCOUNT:
646 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
647 return -EFAULT;
648 break;
649
650 case MEMGETREGIONINFO:
651 {
652 uint32_t ur_idx;
653 struct mtd_erase_region_info *kr;
654 struct region_info_user __user *ur = argp;
655
656 if (get_user(ur_idx, &(ur->regionindex)))
657 return -EFAULT;
658
659 if (ur_idx >= mtd->numeraseregions)
660 return -EINVAL;
661
662 kr = &(mtd->eraseregions[ur_idx]);
663
664 if (put_user(kr->offset, &(ur->offset))
665 || put_user(kr->erasesize, &(ur->erasesize))
666 || put_user(kr->numblocks, &(ur->numblocks)))
667 return -EFAULT;
668
669 break;
670 }
671
672 case MEMGETINFO:
673 memset(&info, 0, sizeof(info));
674 info.type = mtd->type;
675 info.flags = mtd->flags;
676 info.size = mtd->size;
677 info.erasesize = mtd->erasesize;
678 info.writesize = mtd->writesize;
679 info.oobsize = mtd->oobsize;
680 /* The below field is obsolete */
681 info.padding = 0;
682 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
683 return -EFAULT;
684 break;
685
686 case MEMERASE:
687 case MEMERASE64:
688 {
689 struct erase_info *erase;
690
691 if(!(file->f_mode & FMODE_WRITE))
692 return -EPERM;
693
694 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
695 if (!erase)
696 ret = -ENOMEM;
697 else {
698 wait_queue_head_t waitq;
699 DECLARE_WAITQUEUE(wait, current);
700
701 init_waitqueue_head(&waitq);
702
703 if (cmd == MEMERASE64) {
704 struct erase_info_user64 einfo64;
705
706 if (copy_from_user(&einfo64, argp,
707 sizeof(struct erase_info_user64))) {
708 kfree(erase);
709 return -EFAULT;
710 }
711 erase->addr = einfo64.start;
712 erase->len = einfo64.length;
713 } else {
714 struct erase_info_user einfo32;
715
716 if (copy_from_user(&einfo32, argp,
717 sizeof(struct erase_info_user))) {
718 kfree(erase);
719 return -EFAULT;
720 }
721 erase->addr = einfo32.start;
722 erase->len = einfo32.length;
723 }
724 erase->mtd = mtd;
725 erase->callback = mtdchar_erase_callback;
726 erase->priv = (unsigned long)&waitq;
727
728 /*
729 FIXME: Allow INTERRUPTIBLE. Which means
730 not having the wait_queue head on the stack.
731
732 If the wq_head is on the stack, and we
733 leave because we got interrupted, then the
734 wq_head is no longer there when the
735 callback routine tries to wake us up.
736 */
737 ret = mtd_erase(mtd, erase);
738 if (!ret) {
739 set_current_state(TASK_UNINTERRUPTIBLE);
740 add_wait_queue(&waitq, &wait);
741 if (erase->state != MTD_ERASE_DONE &&
742 erase->state != MTD_ERASE_FAILED)
743 schedule();
744 remove_wait_queue(&waitq, &wait);
745 set_current_state(TASK_RUNNING);
746
747 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
748 }
749 kfree(erase);
750 }
751 break;
752 }
753
754 case MEMWRITEOOB:
755 {
756 struct mtd_oob_buf buf;
757 struct mtd_oob_buf __user *buf_user = argp;
758
759 /* NOTE: writes return length to buf_user->length */
760 if (copy_from_user(&buf, argp, sizeof(buf)))
761 ret = -EFAULT;
762 else
763 ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
764 buf.ptr, &buf_user->length);
765 break;
766 }
767
768 case MEMREADOOB:
769 {
770 struct mtd_oob_buf buf;
771 struct mtd_oob_buf __user *buf_user = argp;
772
773 /* NOTE: writes return length to buf_user->start */
774 if (copy_from_user(&buf, argp, sizeof(buf)))
775 ret = -EFAULT;
776 else
777 ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
778 buf.ptr, &buf_user->start);
779 break;
780 }
781
782 case MEMWRITEOOB64:
783 {
784 struct mtd_oob_buf64 buf;
785 struct mtd_oob_buf64 __user *buf_user = argp;
786
787 if (copy_from_user(&buf, argp, sizeof(buf)))
788 ret = -EFAULT;
789 else
790 ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
791 (void __user *)(uintptr_t)buf.usr_ptr,
792 &buf_user->length);
793 break;
794 }
795
796 case MEMREADOOB64:
797 {
798 struct mtd_oob_buf64 buf;
799 struct mtd_oob_buf64 __user *buf_user = argp;
800
801 if (copy_from_user(&buf, argp, sizeof(buf)))
802 ret = -EFAULT;
803 else
804 ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
805 (void __user *)(uintptr_t)buf.usr_ptr,
806 &buf_user->length);
807 break;
808 }
809
810 case MEMWRITE:
811 {
812 ret = mtdchar_write_ioctl(mtd,
813 (struct mtd_write_req __user *)arg);
814 break;
815 }
816
817 case MEMLOCK:
818 {
819 struct erase_info_user einfo;
820
821 if (copy_from_user(&einfo, argp, sizeof(einfo)))
822 return -EFAULT;
823
824 ret = mtd_lock(mtd, einfo.start, einfo.length);
825 break;
826 }
827
828 case MEMUNLOCK:
829 {
830 struct erase_info_user einfo;
831
832 if (copy_from_user(&einfo, argp, sizeof(einfo)))
833 return -EFAULT;
834
835 ret = mtd_unlock(mtd, einfo.start, einfo.length);
836 break;
837 }
838
839 case MEMISLOCKED:
840 {
841 struct erase_info_user einfo;
842
843 if (copy_from_user(&einfo, argp, sizeof(einfo)))
844 return -EFAULT;
845
846 ret = mtd_is_locked(mtd, einfo.start, einfo.length);
847 break;
848 }
849
850 /* Legacy interface */
851 case MEMGETOOBSEL:
852 {
853 struct nand_oobinfo oi;
854
855 if (!mtd->ecclayout)
856 return -EOPNOTSUPP;
857 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
858 return -EINVAL;
859
860 oi.useecc = MTD_NANDECC_AUTOPLACE;
861 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
862 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
863 sizeof(oi.oobfree));
864 oi.eccbytes = mtd->ecclayout->eccbytes;
865
866 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
867 return -EFAULT;
868 break;
869 }
870
871 case MEMGETBADBLOCK:
872 {
873 loff_t offs;
874
875 if (copy_from_user(&offs, argp, sizeof(loff_t)))
876 return -EFAULT;
877 return mtd_block_isbad(mtd, offs);
878 break;
879 }
880
881 case MEMSETBADBLOCK:
882 {
883 loff_t offs;
884
885 if (copy_from_user(&offs, argp, sizeof(loff_t)))
886 return -EFAULT;
887 return mtd_block_markbad(mtd, offs);
888 break;
889 }
890
891#ifdef CONFIG_HAVE_MTD_OTP
892 case OTPSELECT:
893 {
894 int mode;
895 if (copy_from_user(&mode, argp, sizeof(int)))
896 return -EFAULT;
897
898 mfi->mode = MTD_FILE_MODE_NORMAL;
899
900 ret = otp_select_filemode(mfi, mode);
901
902 file->f_pos = 0;
903 break;
904 }
905
906 case OTPGETREGIONCOUNT:
907 case OTPGETREGIONINFO:
908 {
909 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
910 if (!buf)
911 return -ENOMEM;
912 switch (mfi->mode) {
913 case MTD_FILE_MODE_OTP_FACTORY:
914 ret = mtd_get_fact_prot_info(mtd, buf, 4096);
915 break;
916 case MTD_FILE_MODE_OTP_USER:
917 ret = mtd_get_user_prot_info(mtd, buf, 4096);
918 break;
919 default:
920 ret = -EINVAL;
921 break;
922 }
923 if (ret >= 0) {
924 if (cmd == OTPGETREGIONCOUNT) {
925 int nbr = ret / sizeof(struct otp_info);
926 ret = copy_to_user(argp, &nbr, sizeof(int));
927 } else
928 ret = copy_to_user(argp, buf, ret);
929 if (ret)
930 ret = -EFAULT;
931 }
932 kfree(buf);
933 break;
934 }
935
936 case OTPLOCK:
937 {
938 struct otp_info oinfo;
939
940 if (mfi->mode != MTD_FILE_MODE_OTP_USER)
941 return -EINVAL;
942 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
943 return -EFAULT;
944 ret = mtd_lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
945 break;
946 }
947#endif
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 (!mtd->ecclayout)
955 return -EOPNOTSUPP;
956
957 usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
958 if (!usrlay)
959 return -ENOMEM;
960
961 shrink_ecclayout(mtd->ecclayout, 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
992 case MTD_FILE_MODE_NORMAL:
993 break;
994 default:
995 ret = -EINVAL;
996 }
997 file->f_pos = 0;
998 break;
999 }
1000
1001 case BLKPG:
1002 {
1003 ret = mtdchar_blkpg_ioctl(mtd,
1004 (struct blkpg_ioctl_arg __user *)arg);
1005 break;
1006 }
1007
1008 case BLKRRPART:
1009 {
1010 /* No reread partition feature. Just return ok */
1011 ret = 0;
1012 break;
1013 }
1014
1015 default:
1016 ret = -ENOTTY;
1017 }
1018
1019 return ret;
1020} /* memory_ioctl */
1021
1022static long mtdchar_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
1023{
1024 int ret;
1025
1026 mutex_lock(&mtd_mutex);
1027 ret = mtdchar_ioctl(file, cmd, arg);
1028 mutex_unlock(&mtd_mutex);
1029
1030 return ret;
1031}
1032
1033#ifdef CONFIG_COMPAT
1034
1035struct mtd_oob_buf32 {
1036 u_int32_t start;
1037 u_int32_t length;
1038 compat_caddr_t ptr; /* unsigned char* */
1039};
1040
1041#define MEMWRITEOOB32 _IOWR('M', 3, struct mtd_oob_buf32)
1042#define MEMREADOOB32 _IOWR('M', 4, struct mtd_oob_buf32)
1043
1044static long mtdchar_compat_ioctl(struct file *file, unsigned int cmd,
1045 unsigned long arg)
1046{
1047 struct mtd_file_info *mfi = file->private_data;
1048 struct mtd_info *mtd = mfi->mtd;
1049 void __user *argp = compat_ptr(arg);
1050 int ret = 0;
1051
1052 mutex_lock(&mtd_mutex);
1053
1054 switch (cmd) {
1055 case MEMWRITEOOB32:
1056 {
1057 struct mtd_oob_buf32 buf;
1058 struct mtd_oob_buf32 __user *buf_user = argp;
1059
1060 if (copy_from_user(&buf, argp, sizeof(buf)))
1061 ret = -EFAULT;
1062 else
1063 ret = mtdchar_writeoob(file, mtd, buf.start,
1064 buf.length, compat_ptr(buf.ptr),
1065 &buf_user->length);
1066 break;
1067 }
1068
1069 case MEMREADOOB32:
1070 {
1071 struct mtd_oob_buf32 buf;
1072 struct mtd_oob_buf32 __user *buf_user = argp;
1073
1074 /* NOTE: writes return length to buf->start */
1075 if (copy_from_user(&buf, argp, sizeof(buf)))
1076 ret = -EFAULT;
1077 else
1078 ret = mtdchar_readoob(file, mtd, buf.start,
1079 buf.length, compat_ptr(buf.ptr),
1080 &buf_user->start);
1081 break;
1082 }
1083 default:
1084 ret = mtdchar_ioctl(file, cmd, (unsigned long)argp);
1085 }
1086
1087 mutex_unlock(&mtd_mutex);
1088
1089 return ret;
1090}
1091
1092#endif /* CONFIG_COMPAT */
1093
1094/*
1095 * try to determine where a shared mapping can be made
1096 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
1097 * mappings)
1098 */
1099#ifndef CONFIG_MMU
1100static unsigned long mtdchar_get_unmapped_area(struct file *file,
1101 unsigned long addr,
1102 unsigned long len,
1103 unsigned long pgoff,
1104 unsigned long flags)
1105{
1106 struct mtd_file_info *mfi = file->private_data;
1107 struct mtd_info *mtd = mfi->mtd;
1108 unsigned long offset;
1109 int ret;
1110
1111 if (addr != 0)
1112 return (unsigned long) -EINVAL;
1113
1114 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
1115 return (unsigned long) -EINVAL;
1116
1117 offset = pgoff << PAGE_SHIFT;
1118 if (offset > mtd->size - len)
1119 return (unsigned long) -EINVAL;
1120
1121 ret = mtd_get_unmapped_area(mtd, len, offset, flags);
1122 return ret == -EOPNOTSUPP ? -ENOSYS : ret;
1123}
1124#endif
1125
1126/*
1127 * set up a mapping for shared memory segments
1128 */
1129static int mtdchar_mmap(struct file *file, struct vm_area_struct *vma)
1130{
1131#ifdef CONFIG_MMU
1132 struct mtd_file_info *mfi = file->private_data;
1133 struct mtd_info *mtd = mfi->mtd;
1134 struct map_info *map = mtd->priv;
1135 unsigned long start;
1136 unsigned long off;
1137 u32 len;
1138
1139 if (mtd->type == MTD_RAM || mtd->type == MTD_ROM) {
1140 off = vma->vm_pgoff << PAGE_SHIFT;
1141 start = map->phys;
1142 len = PAGE_ALIGN((start & ~PAGE_MASK) + map->size);
1143 start &= PAGE_MASK;
1144 if ((vma->vm_end - vma->vm_start + off) > len)
1145 return -EINVAL;
1146
1147 off += start;
1148 vma->vm_pgoff = off >> PAGE_SHIFT;
1149 vma->vm_flags |= VM_IO | VM_RESERVED;
1150
1151#ifdef pgprot_noncached
1152 if (file->f_flags & O_DSYNC || off >= __pa(high_memory))
1153 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1154#endif
1155 if (io_remap_pfn_range(vma, vma->vm_start, off >> PAGE_SHIFT,
1156 vma->vm_end - vma->vm_start,
1157 vma->vm_page_prot))
1158 return -EAGAIN;
1159
1160 return 0;
1161 }
1162 return -ENOSYS;
1163#else
1164 return vma->vm_flags & VM_SHARED ? 0 : -ENOSYS;
1165#endif
1166}
1167
1168static const struct file_operations mtd_fops = {
1169 .owner = THIS_MODULE,
1170 .llseek = mtdchar_lseek,
1171 .read = mtdchar_read,
1172 .write = mtdchar_write,
1173 .unlocked_ioctl = mtdchar_unlocked_ioctl,
1174#ifdef CONFIG_COMPAT
1175 .compat_ioctl = mtdchar_compat_ioctl,
1176#endif
1177 .open = mtdchar_open,
1178 .release = mtdchar_close,
1179 .mmap = mtdchar_mmap,
1180#ifndef CONFIG_MMU
1181 .get_unmapped_area = mtdchar_get_unmapped_area,
1182#endif
1183};
1184
1185static const struct super_operations mtd_ops = {
1186 .drop_inode = generic_delete_inode,
1187 .statfs = simple_statfs,
1188};
1189
1190static struct dentry *mtd_inodefs_mount(struct file_system_type *fs_type,
1191 int flags, const char *dev_name, void *data)
1192{
1193 return mount_pseudo(fs_type, "mtd_inode:", &mtd_ops, NULL, MTD_INODE_FS_MAGIC);
1194}
1195
1196static struct file_system_type mtd_inodefs_type = {
1197 .name = "mtd_inodefs",
1198 .mount = mtd_inodefs_mount,
1199 .kill_sb = kill_anon_super,
1200};
1201
1202static int __init init_mtdchar(void)
1203{
1204 int ret;
1205
1206 ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1207 "mtd", &mtd_fops);
1208 if (ret < 0) {
1209 pr_notice("Can't allocate major number %d for "
1210 "Memory Technology Devices.\n", MTD_CHAR_MAJOR);
1211 return ret;
1212 }
1213
1214 ret = register_filesystem(&mtd_inodefs_type);
1215 if (ret) {
1216 pr_notice("Can't register mtd_inodefs filesystem: %d\n", ret);
1217 goto err_unregister_chdev;
1218 }
1219 return ret;
1220
1221err_unregister_chdev:
1222 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1223 return ret;
1224}
1225
1226static void __exit cleanup_mtdchar(void)
1227{
1228 unregister_filesystem(&mtd_inodefs_type);
1229 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1230}
1231
1232module_init(init_mtdchar);
1233module_exit(cleanup_mtdchar);
1234
1235MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
1236
1237MODULE_LICENSE("GPL");
1238MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1239MODULE_DESCRIPTION("Direct character-device access to MTD devices");
1240MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);