Loading...
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/mtd/mtd.h>
35#include <linux/mtd/partitions.h>
36#include <linux/mtd/map.h>
37
38#include <asm/uaccess.h>
39
40#define MTD_INODE_FS_MAGIC 0x11307854
41static DEFINE_MUTEX(mtd_mutex);
42static struct vfsmount *mtd_inode_mnt __read_mostly;
43
44/*
45 * Data structure to hold the pointer to the mtd device as well
46 * as mode information ofr various use cases.
47 */
48struct mtd_file_info {
49 struct mtd_info *mtd;
50 struct inode *ino;
51 enum mtd_file_modes mode;
52};
53
54static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
55{
56 struct mtd_file_info *mfi = file->private_data;
57 struct mtd_info *mtd = mfi->mtd;
58
59 switch (orig) {
60 case SEEK_SET:
61 break;
62 case SEEK_CUR:
63 offset += file->f_pos;
64 break;
65 case SEEK_END:
66 offset += mtd->size;
67 break;
68 default:
69 return -EINVAL;
70 }
71
72 if (offset >= 0 && offset <= mtd->size)
73 return file->f_pos = offset;
74
75 return -EINVAL;
76}
77
78
79
80static int mtd_open(struct inode *inode, struct file *file)
81{
82 int minor = iminor(inode);
83 int devnum = minor >> 1;
84 int ret = 0;
85 struct mtd_info *mtd;
86 struct mtd_file_info *mfi;
87 struct inode *mtd_ino;
88
89 DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
90
91 /* You can't open the RO devices RW */
92 if ((file->f_mode & FMODE_WRITE) && (minor & 1))
93 return -EACCES;
94
95 mutex_lock(&mtd_mutex);
96 mtd = get_mtd_device(NULL, devnum);
97
98 if (IS_ERR(mtd)) {
99 ret = PTR_ERR(mtd);
100 goto out;
101 }
102
103 if (mtd->type == MTD_ABSENT) {
104 put_mtd_device(mtd);
105 ret = -ENODEV;
106 goto out;
107 }
108
109 mtd_ino = iget_locked(mtd_inode_mnt->mnt_sb, devnum);
110 if (!mtd_ino) {
111 put_mtd_device(mtd);
112 ret = -ENOMEM;
113 goto out;
114 }
115 if (mtd_ino->i_state & I_NEW) {
116 mtd_ino->i_private = mtd;
117 mtd_ino->i_mode = S_IFCHR;
118 mtd_ino->i_data.backing_dev_info = mtd->backing_dev_info;
119 unlock_new_inode(mtd_ino);
120 }
121 file->f_mapping = mtd_ino->i_mapping;
122
123 /* You can't open it RW if it's not a writeable device */
124 if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
125 iput(mtd_ino);
126 put_mtd_device(mtd);
127 ret = -EACCES;
128 goto out;
129 }
130
131 mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
132 if (!mfi) {
133 iput(mtd_ino);
134 put_mtd_device(mtd);
135 ret = -ENOMEM;
136 goto out;
137 }
138 mfi->ino = mtd_ino;
139 mfi->mtd = mtd;
140 file->private_data = mfi;
141
142out:
143 mutex_unlock(&mtd_mutex);
144 return ret;
145} /* mtd_open */
146
147/*====================================================================*/
148
149static int mtd_close(struct inode *inode, struct file *file)
150{
151 struct mtd_file_info *mfi = file->private_data;
152 struct mtd_info *mtd = mfi->mtd;
153
154 DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
155
156 /* Only sync if opened RW */
157 if ((file->f_mode & FMODE_WRITE) && mtd->sync)
158 mtd->sync(mtd);
159
160 iput(mfi->ino);
161
162 put_mtd_device(mtd);
163 file->private_data = NULL;
164 kfree(mfi);
165
166 return 0;
167} /* mtd_close */
168
169/* Back in June 2001, dwmw2 wrote:
170 *
171 * FIXME: This _really_ needs to die. In 2.5, we should lock the
172 * userspace buffer down and use it directly with readv/writev.
173 *
174 * The implementation below, using mtd_kmalloc_up_to, mitigates
175 * allocation failures when the system is under low-memory situations
176 * or if memory is highly fragmented at the cost of reducing the
177 * performance of the requested transfer due to a smaller buffer size.
178 *
179 * A more complex but more memory-efficient implementation based on
180 * get_user_pages and iovecs to cover extents of those pages is a
181 * longer-term goal, as intimated by dwmw2 above. However, for the
182 * write case, this requires yet more complex head and tail transfer
183 * handling when those head and tail offsets and sizes are such that
184 * alignment requirements are not met in the NAND subdriver.
185 */
186
187static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
188{
189 struct mtd_file_info *mfi = file->private_data;
190 struct mtd_info *mtd = mfi->mtd;
191 size_t retlen=0;
192 size_t total_retlen=0;
193 int ret=0;
194 int len;
195 size_t size = count;
196 char *kbuf;
197
198 DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
199
200 if (*ppos + count > mtd->size)
201 count = mtd->size - *ppos;
202
203 if (!count)
204 return 0;
205
206 kbuf = mtd_kmalloc_up_to(mtd, &size);
207 if (!kbuf)
208 return -ENOMEM;
209
210 while (count) {
211 len = min_t(size_t, count, size);
212
213 switch (mfi->mode) {
214 case MTD_MODE_OTP_FACTORY:
215 ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
216 break;
217 case MTD_MODE_OTP_USER:
218 ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
219 break;
220 case MTD_MODE_RAW:
221 {
222 struct mtd_oob_ops ops;
223
224 ops.mode = MTD_OOB_RAW;
225 ops.datbuf = kbuf;
226 ops.oobbuf = NULL;
227 ops.len = len;
228
229 ret = mtd->read_oob(mtd, *ppos, &ops);
230 retlen = ops.retlen;
231 break;
232 }
233 default:
234 ret = mtd->read(mtd, *ppos, len, &retlen, kbuf);
235 }
236 /* Nand returns -EBADMSG on ecc errors, but it returns
237 * the data. For our userspace tools it is important
238 * to dump areas with ecc errors !
239 * For kernel internal usage it also might return -EUCLEAN
240 * to signal the caller that a bitflip has occurred and has
241 * been corrected by the ECC algorithm.
242 * Userspace software which accesses NAND this way
243 * must be aware of the fact that it deals with NAND
244 */
245 if (!ret || (ret == -EUCLEAN) || (ret == -EBADMSG)) {
246 *ppos += retlen;
247 if (copy_to_user(buf, kbuf, retlen)) {
248 kfree(kbuf);
249 return -EFAULT;
250 }
251 else
252 total_retlen += retlen;
253
254 count -= retlen;
255 buf += retlen;
256 if (retlen == 0)
257 count = 0;
258 }
259 else {
260 kfree(kbuf);
261 return ret;
262 }
263
264 }
265
266 kfree(kbuf);
267 return total_retlen;
268} /* mtd_read */
269
270static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
271{
272 struct mtd_file_info *mfi = file->private_data;
273 struct mtd_info *mtd = mfi->mtd;
274 size_t size = count;
275 char *kbuf;
276 size_t retlen;
277 size_t total_retlen=0;
278 int ret=0;
279 int len;
280
281 DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
282
283 if (*ppos == mtd->size)
284 return -ENOSPC;
285
286 if (*ppos + count > mtd->size)
287 count = mtd->size - *ppos;
288
289 if (!count)
290 return 0;
291
292 kbuf = mtd_kmalloc_up_to(mtd, &size);
293 if (!kbuf)
294 return -ENOMEM;
295
296 while (count) {
297 len = min_t(size_t, count, size);
298
299 if (copy_from_user(kbuf, buf, len)) {
300 kfree(kbuf);
301 return -EFAULT;
302 }
303
304 switch (mfi->mode) {
305 case MTD_MODE_OTP_FACTORY:
306 ret = -EROFS;
307 break;
308 case MTD_MODE_OTP_USER:
309 if (!mtd->write_user_prot_reg) {
310 ret = -EOPNOTSUPP;
311 break;
312 }
313 ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
314 break;
315
316 case MTD_MODE_RAW:
317 {
318 struct mtd_oob_ops ops;
319
320 ops.mode = MTD_OOB_RAW;
321 ops.datbuf = kbuf;
322 ops.oobbuf = NULL;
323 ops.len = len;
324
325 ret = mtd->write_oob(mtd, *ppos, &ops);
326 retlen = ops.retlen;
327 break;
328 }
329
330 default:
331 ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
332 }
333 if (!ret) {
334 *ppos += retlen;
335 total_retlen += retlen;
336 count -= retlen;
337 buf += retlen;
338 }
339 else {
340 kfree(kbuf);
341 return ret;
342 }
343 }
344
345 kfree(kbuf);
346 return total_retlen;
347} /* mtd_write */
348
349/*======================================================================
350
351 IOCTL calls for getting device parameters.
352
353======================================================================*/
354static void mtdchar_erase_callback (struct erase_info *instr)
355{
356 wake_up((wait_queue_head_t *)instr->priv);
357}
358
359#ifdef CONFIG_HAVE_MTD_OTP
360static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
361{
362 struct mtd_info *mtd = mfi->mtd;
363 int ret = 0;
364
365 switch (mode) {
366 case MTD_OTP_FACTORY:
367 if (!mtd->read_fact_prot_reg)
368 ret = -EOPNOTSUPP;
369 else
370 mfi->mode = MTD_MODE_OTP_FACTORY;
371 break;
372 case MTD_OTP_USER:
373 if (!mtd->read_fact_prot_reg)
374 ret = -EOPNOTSUPP;
375 else
376 mfi->mode = MTD_MODE_OTP_USER;
377 break;
378 default:
379 ret = -EINVAL;
380 case MTD_OTP_OFF:
381 break;
382 }
383 return ret;
384}
385#else
386# define otp_select_filemode(f,m) -EOPNOTSUPP
387#endif
388
389static int mtd_do_writeoob(struct file *file, struct mtd_info *mtd,
390 uint64_t start, uint32_t length, void __user *ptr,
391 uint32_t __user *retp)
392{
393 struct mtd_oob_ops ops;
394 uint32_t retlen;
395 int ret = 0;
396
397 if (!(file->f_mode & FMODE_WRITE))
398 return -EPERM;
399
400 if (length > 4096)
401 return -EINVAL;
402
403 if (!mtd->write_oob)
404 ret = -EOPNOTSUPP;
405 else
406 ret = access_ok(VERIFY_READ, ptr, length) ? 0 : -EFAULT;
407
408 if (ret)
409 return ret;
410
411 ops.ooblen = length;
412 ops.ooboffs = start & (mtd->oobsize - 1);
413 ops.datbuf = NULL;
414 ops.mode = MTD_OOB_PLACE;
415
416 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
417 return -EINVAL;
418
419 ops.oobbuf = memdup_user(ptr, length);
420 if (IS_ERR(ops.oobbuf))
421 return PTR_ERR(ops.oobbuf);
422
423 start &= ~((uint64_t)mtd->oobsize - 1);
424 ret = mtd->write_oob(mtd, start, &ops);
425
426 if (ops.oobretlen > 0xFFFFFFFFU)
427 ret = -EOVERFLOW;
428 retlen = ops.oobretlen;
429 if (copy_to_user(retp, &retlen, sizeof(length)))
430 ret = -EFAULT;
431
432 kfree(ops.oobbuf);
433 return ret;
434}
435
436static int mtd_do_readoob(struct mtd_info *mtd, uint64_t start,
437 uint32_t length, void __user *ptr, uint32_t __user *retp)
438{
439 struct mtd_oob_ops ops;
440 int ret = 0;
441
442 if (length > 4096)
443 return -EINVAL;
444
445 if (!mtd->read_oob)
446 ret = -EOPNOTSUPP;
447 else
448 ret = access_ok(VERIFY_WRITE, ptr,
449 length) ? 0 : -EFAULT;
450 if (ret)
451 return ret;
452
453 ops.ooblen = length;
454 ops.ooboffs = start & (mtd->oobsize - 1);
455 ops.datbuf = NULL;
456 ops.mode = MTD_OOB_PLACE;
457
458 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
459 return -EINVAL;
460
461 ops.oobbuf = kmalloc(length, GFP_KERNEL);
462 if (!ops.oobbuf)
463 return -ENOMEM;
464
465 start &= ~((uint64_t)mtd->oobsize - 1);
466 ret = mtd->read_oob(mtd, start, &ops);
467
468 if (put_user(ops.oobretlen, retp))
469 ret = -EFAULT;
470 else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
471 ops.oobretlen))
472 ret = -EFAULT;
473
474 kfree(ops.oobbuf);
475 return ret;
476}
477
478/*
479 * Copies (and truncates, if necessary) data from the larger struct,
480 * nand_ecclayout, to the smaller, deprecated layout struct,
481 * nand_ecclayout_user. This is necessary only to suppport the deprecated
482 * API ioctl ECCGETLAYOUT while allowing all new functionality to use
483 * nand_ecclayout flexibly (i.e. the struct may change size in new
484 * releases without requiring major rewrites).
485 */
486static int shrink_ecclayout(const struct nand_ecclayout *from,
487 struct nand_ecclayout_user *to)
488{
489 int i;
490
491 if (!from || !to)
492 return -EINVAL;
493
494 memset(to, 0, sizeof(*to));
495
496 to->eccbytes = min((int)from->eccbytes, MTD_MAX_ECCPOS_ENTRIES);
497 for (i = 0; i < to->eccbytes; i++)
498 to->eccpos[i] = from->eccpos[i];
499
500 for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
501 if (from->oobfree[i].length == 0 &&
502 from->oobfree[i].offset == 0)
503 break;
504 to->oobavail += from->oobfree[i].length;
505 to->oobfree[i] = from->oobfree[i];
506 }
507
508 return 0;
509}
510
511static int mtd_blkpg_ioctl(struct mtd_info *mtd,
512 struct blkpg_ioctl_arg __user *arg)
513{
514 struct blkpg_ioctl_arg a;
515 struct blkpg_partition p;
516
517 if (!capable(CAP_SYS_ADMIN))
518 return -EPERM;
519
520 if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
521 return -EFAULT;
522
523 if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
524 return -EFAULT;
525
526 switch (a.op) {
527 case BLKPG_ADD_PARTITION:
528
529 /* Only master mtd device must be used to add partitions */
530 if (mtd_is_partition(mtd))
531 return -EINVAL;
532
533 return mtd_add_partition(mtd, p.devname, p.start, p.length);
534
535 case BLKPG_DEL_PARTITION:
536
537 if (p.pno < 0)
538 return -EINVAL;
539
540 return mtd_del_partition(mtd, p.pno);
541
542 default:
543 return -EINVAL;
544 }
545}
546
547static int mtd_ioctl(struct file *file, u_int cmd, u_long arg)
548{
549 struct mtd_file_info *mfi = file->private_data;
550 struct mtd_info *mtd = mfi->mtd;
551 void __user *argp = (void __user *)arg;
552 int ret = 0;
553 u_long size;
554 struct mtd_info_user info;
555
556 DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
557
558 size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
559 if (cmd & IOC_IN) {
560 if (!access_ok(VERIFY_READ, argp, size))
561 return -EFAULT;
562 }
563 if (cmd & IOC_OUT) {
564 if (!access_ok(VERIFY_WRITE, argp, size))
565 return -EFAULT;
566 }
567
568 switch (cmd) {
569 case MEMGETREGIONCOUNT:
570 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
571 return -EFAULT;
572 break;
573
574 case MEMGETREGIONINFO:
575 {
576 uint32_t ur_idx;
577 struct mtd_erase_region_info *kr;
578 struct region_info_user __user *ur = argp;
579
580 if (get_user(ur_idx, &(ur->regionindex)))
581 return -EFAULT;
582
583 if (ur_idx >= mtd->numeraseregions)
584 return -EINVAL;
585
586 kr = &(mtd->eraseregions[ur_idx]);
587
588 if (put_user(kr->offset, &(ur->offset))
589 || put_user(kr->erasesize, &(ur->erasesize))
590 || put_user(kr->numblocks, &(ur->numblocks)))
591 return -EFAULT;
592
593 break;
594 }
595
596 case MEMGETINFO:
597 memset(&info, 0, sizeof(info));
598 info.type = mtd->type;
599 info.flags = mtd->flags;
600 info.size = mtd->size;
601 info.erasesize = mtd->erasesize;
602 info.writesize = mtd->writesize;
603 info.oobsize = mtd->oobsize;
604 /* The below fields are obsolete */
605 info.ecctype = -1;
606 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
607 return -EFAULT;
608 break;
609
610 case MEMERASE:
611 case MEMERASE64:
612 {
613 struct erase_info *erase;
614
615 if(!(file->f_mode & FMODE_WRITE))
616 return -EPERM;
617
618 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
619 if (!erase)
620 ret = -ENOMEM;
621 else {
622 wait_queue_head_t waitq;
623 DECLARE_WAITQUEUE(wait, current);
624
625 init_waitqueue_head(&waitq);
626
627 if (cmd == MEMERASE64) {
628 struct erase_info_user64 einfo64;
629
630 if (copy_from_user(&einfo64, argp,
631 sizeof(struct erase_info_user64))) {
632 kfree(erase);
633 return -EFAULT;
634 }
635 erase->addr = einfo64.start;
636 erase->len = einfo64.length;
637 } else {
638 struct erase_info_user einfo32;
639
640 if (copy_from_user(&einfo32, argp,
641 sizeof(struct erase_info_user))) {
642 kfree(erase);
643 return -EFAULT;
644 }
645 erase->addr = einfo32.start;
646 erase->len = einfo32.length;
647 }
648 erase->mtd = mtd;
649 erase->callback = mtdchar_erase_callback;
650 erase->priv = (unsigned long)&waitq;
651
652 /*
653 FIXME: Allow INTERRUPTIBLE. Which means
654 not having the wait_queue head on the stack.
655
656 If the wq_head is on the stack, and we
657 leave because we got interrupted, then the
658 wq_head is no longer there when the
659 callback routine tries to wake us up.
660 */
661 ret = mtd->erase(mtd, erase);
662 if (!ret) {
663 set_current_state(TASK_UNINTERRUPTIBLE);
664 add_wait_queue(&waitq, &wait);
665 if (erase->state != MTD_ERASE_DONE &&
666 erase->state != MTD_ERASE_FAILED)
667 schedule();
668 remove_wait_queue(&waitq, &wait);
669 set_current_state(TASK_RUNNING);
670
671 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
672 }
673 kfree(erase);
674 }
675 break;
676 }
677
678 case MEMWRITEOOB:
679 {
680 struct mtd_oob_buf buf;
681 struct mtd_oob_buf __user *buf_user = argp;
682
683 /* NOTE: writes return length to buf_user->length */
684 if (copy_from_user(&buf, argp, sizeof(buf)))
685 ret = -EFAULT;
686 else
687 ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
688 buf.ptr, &buf_user->length);
689 break;
690 }
691
692 case MEMREADOOB:
693 {
694 struct mtd_oob_buf buf;
695 struct mtd_oob_buf __user *buf_user = argp;
696
697 /* NOTE: writes return length to buf_user->start */
698 if (copy_from_user(&buf, argp, sizeof(buf)))
699 ret = -EFAULT;
700 else
701 ret = mtd_do_readoob(mtd, buf.start, buf.length,
702 buf.ptr, &buf_user->start);
703 break;
704 }
705
706 case MEMWRITEOOB64:
707 {
708 struct mtd_oob_buf64 buf;
709 struct mtd_oob_buf64 __user *buf_user = argp;
710
711 if (copy_from_user(&buf, argp, sizeof(buf)))
712 ret = -EFAULT;
713 else
714 ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
715 (void __user *)(uintptr_t)buf.usr_ptr,
716 &buf_user->length);
717 break;
718 }
719
720 case MEMREADOOB64:
721 {
722 struct mtd_oob_buf64 buf;
723 struct mtd_oob_buf64 __user *buf_user = argp;
724
725 if (copy_from_user(&buf, argp, sizeof(buf)))
726 ret = -EFAULT;
727 else
728 ret = mtd_do_readoob(mtd, buf.start, buf.length,
729 (void __user *)(uintptr_t)buf.usr_ptr,
730 &buf_user->length);
731 break;
732 }
733
734 case MEMLOCK:
735 {
736 struct erase_info_user einfo;
737
738 if (copy_from_user(&einfo, argp, sizeof(einfo)))
739 return -EFAULT;
740
741 if (!mtd->lock)
742 ret = -EOPNOTSUPP;
743 else
744 ret = mtd->lock(mtd, einfo.start, einfo.length);
745 break;
746 }
747
748 case MEMUNLOCK:
749 {
750 struct erase_info_user einfo;
751
752 if (copy_from_user(&einfo, argp, sizeof(einfo)))
753 return -EFAULT;
754
755 if (!mtd->unlock)
756 ret = -EOPNOTSUPP;
757 else
758 ret = mtd->unlock(mtd, einfo.start, einfo.length);
759 break;
760 }
761
762 case MEMISLOCKED:
763 {
764 struct erase_info_user einfo;
765
766 if (copy_from_user(&einfo, argp, sizeof(einfo)))
767 return -EFAULT;
768
769 if (!mtd->is_locked)
770 ret = -EOPNOTSUPP;
771 else
772 ret = mtd->is_locked(mtd, einfo.start, einfo.length);
773 break;
774 }
775
776 /* Legacy interface */
777 case MEMGETOOBSEL:
778 {
779 struct nand_oobinfo oi;
780
781 if (!mtd->ecclayout)
782 return -EOPNOTSUPP;
783 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
784 return -EINVAL;
785
786 oi.useecc = MTD_NANDECC_AUTOPLACE;
787 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
788 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
789 sizeof(oi.oobfree));
790 oi.eccbytes = mtd->ecclayout->eccbytes;
791
792 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
793 return -EFAULT;
794 break;
795 }
796
797 case MEMGETBADBLOCK:
798 {
799 loff_t offs;
800
801 if (copy_from_user(&offs, argp, sizeof(loff_t)))
802 return -EFAULT;
803 if (!mtd->block_isbad)
804 ret = -EOPNOTSUPP;
805 else
806 return mtd->block_isbad(mtd, offs);
807 break;
808 }
809
810 case MEMSETBADBLOCK:
811 {
812 loff_t offs;
813
814 if (copy_from_user(&offs, argp, sizeof(loff_t)))
815 return -EFAULT;
816 if (!mtd->block_markbad)
817 ret = -EOPNOTSUPP;
818 else
819 return mtd->block_markbad(mtd, offs);
820 break;
821 }
822
823#ifdef CONFIG_HAVE_MTD_OTP
824 case OTPSELECT:
825 {
826 int mode;
827 if (copy_from_user(&mode, argp, sizeof(int)))
828 return -EFAULT;
829
830 mfi->mode = MTD_MODE_NORMAL;
831
832 ret = otp_select_filemode(mfi, mode);
833
834 file->f_pos = 0;
835 break;
836 }
837
838 case OTPGETREGIONCOUNT:
839 case OTPGETREGIONINFO:
840 {
841 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
842 if (!buf)
843 return -ENOMEM;
844 ret = -EOPNOTSUPP;
845 switch (mfi->mode) {
846 case MTD_MODE_OTP_FACTORY:
847 if (mtd->get_fact_prot_info)
848 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
849 break;
850 case MTD_MODE_OTP_USER:
851 if (mtd->get_user_prot_info)
852 ret = mtd->get_user_prot_info(mtd, buf, 4096);
853 break;
854 default:
855 break;
856 }
857 if (ret >= 0) {
858 if (cmd == OTPGETREGIONCOUNT) {
859 int nbr = ret / sizeof(struct otp_info);
860 ret = copy_to_user(argp, &nbr, sizeof(int));
861 } else
862 ret = copy_to_user(argp, buf, ret);
863 if (ret)
864 ret = -EFAULT;
865 }
866 kfree(buf);
867 break;
868 }
869
870 case OTPLOCK:
871 {
872 struct otp_info oinfo;
873
874 if (mfi->mode != MTD_MODE_OTP_USER)
875 return -EINVAL;
876 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
877 return -EFAULT;
878 if (!mtd->lock_user_prot_reg)
879 return -EOPNOTSUPP;
880 ret = mtd->lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
881 break;
882 }
883#endif
884
885 /* This ioctl is being deprecated - it truncates the ecc layout */
886 case ECCGETLAYOUT:
887 {
888 struct nand_ecclayout_user *usrlay;
889
890 if (!mtd->ecclayout)
891 return -EOPNOTSUPP;
892
893 usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
894 if (!usrlay)
895 return -ENOMEM;
896
897 shrink_ecclayout(mtd->ecclayout, usrlay);
898
899 if (copy_to_user(argp, usrlay, sizeof(*usrlay)))
900 ret = -EFAULT;
901 kfree(usrlay);
902 break;
903 }
904
905 case ECCGETSTATS:
906 {
907 if (copy_to_user(argp, &mtd->ecc_stats,
908 sizeof(struct mtd_ecc_stats)))
909 return -EFAULT;
910 break;
911 }
912
913 case MTDFILEMODE:
914 {
915 mfi->mode = 0;
916
917 switch(arg) {
918 case MTD_MODE_OTP_FACTORY:
919 case MTD_MODE_OTP_USER:
920 ret = otp_select_filemode(mfi, arg);
921 break;
922
923 case MTD_MODE_RAW:
924 if (!mtd->read_oob || !mtd->write_oob)
925 return -EOPNOTSUPP;
926 mfi->mode = arg;
927
928 case MTD_MODE_NORMAL:
929 break;
930 default:
931 ret = -EINVAL;
932 }
933 file->f_pos = 0;
934 break;
935 }
936
937 case BLKPG:
938 {
939 ret = mtd_blkpg_ioctl(mtd,
940 (struct blkpg_ioctl_arg __user *)arg);
941 break;
942 }
943
944 case BLKRRPART:
945 {
946 /* No reread partition feature. Just return ok */
947 ret = 0;
948 break;
949 }
950
951 default:
952 ret = -ENOTTY;
953 }
954
955 return ret;
956} /* memory_ioctl */
957
958static long mtd_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
959{
960 int ret;
961
962 mutex_lock(&mtd_mutex);
963 ret = mtd_ioctl(file, cmd, arg);
964 mutex_unlock(&mtd_mutex);
965
966 return ret;
967}
968
969#ifdef CONFIG_COMPAT
970
971struct mtd_oob_buf32 {
972 u_int32_t start;
973 u_int32_t length;
974 compat_caddr_t ptr; /* unsigned char* */
975};
976
977#define MEMWRITEOOB32 _IOWR('M', 3, struct mtd_oob_buf32)
978#define MEMREADOOB32 _IOWR('M', 4, struct mtd_oob_buf32)
979
980static long mtd_compat_ioctl(struct file *file, unsigned int cmd,
981 unsigned long arg)
982{
983 struct mtd_file_info *mfi = file->private_data;
984 struct mtd_info *mtd = mfi->mtd;
985 void __user *argp = compat_ptr(arg);
986 int ret = 0;
987
988 mutex_lock(&mtd_mutex);
989
990 switch (cmd) {
991 case MEMWRITEOOB32:
992 {
993 struct mtd_oob_buf32 buf;
994 struct mtd_oob_buf32 __user *buf_user = argp;
995
996 if (copy_from_user(&buf, argp, sizeof(buf)))
997 ret = -EFAULT;
998 else
999 ret = mtd_do_writeoob(file, mtd, buf.start,
1000 buf.length, compat_ptr(buf.ptr),
1001 &buf_user->length);
1002 break;
1003 }
1004
1005 case MEMREADOOB32:
1006 {
1007 struct mtd_oob_buf32 buf;
1008 struct mtd_oob_buf32 __user *buf_user = argp;
1009
1010 /* NOTE: writes return length to buf->start */
1011 if (copy_from_user(&buf, argp, sizeof(buf)))
1012 ret = -EFAULT;
1013 else
1014 ret = mtd_do_readoob(mtd, buf.start,
1015 buf.length, compat_ptr(buf.ptr),
1016 &buf_user->start);
1017 break;
1018 }
1019 default:
1020 ret = mtd_ioctl(file, cmd, (unsigned long)argp);
1021 }
1022
1023 mutex_unlock(&mtd_mutex);
1024
1025 return ret;
1026}
1027
1028#endif /* CONFIG_COMPAT */
1029
1030/*
1031 * try to determine where a shared mapping can be made
1032 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
1033 * mappings)
1034 */
1035#ifndef CONFIG_MMU
1036static unsigned long mtd_get_unmapped_area(struct file *file,
1037 unsigned long addr,
1038 unsigned long len,
1039 unsigned long pgoff,
1040 unsigned long flags)
1041{
1042 struct mtd_file_info *mfi = file->private_data;
1043 struct mtd_info *mtd = mfi->mtd;
1044
1045 if (mtd->get_unmapped_area) {
1046 unsigned long offset;
1047
1048 if (addr != 0)
1049 return (unsigned long) -EINVAL;
1050
1051 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
1052 return (unsigned long) -EINVAL;
1053
1054 offset = pgoff << PAGE_SHIFT;
1055 if (offset > mtd->size - len)
1056 return (unsigned long) -EINVAL;
1057
1058 return mtd->get_unmapped_area(mtd, len, offset, flags);
1059 }
1060
1061 /* can't map directly */
1062 return (unsigned long) -ENOSYS;
1063}
1064#endif
1065
1066/*
1067 * set up a mapping for shared memory segments
1068 */
1069static int mtd_mmap(struct file *file, struct vm_area_struct *vma)
1070{
1071#ifdef CONFIG_MMU
1072 struct mtd_file_info *mfi = file->private_data;
1073 struct mtd_info *mtd = mfi->mtd;
1074 struct map_info *map = mtd->priv;
1075 unsigned long start;
1076 unsigned long off;
1077 u32 len;
1078
1079 if (mtd->type == MTD_RAM || mtd->type == MTD_ROM) {
1080 off = vma->vm_pgoff << PAGE_SHIFT;
1081 start = map->phys;
1082 len = PAGE_ALIGN((start & ~PAGE_MASK) + map->size);
1083 start &= PAGE_MASK;
1084 if ((vma->vm_end - vma->vm_start + off) > len)
1085 return -EINVAL;
1086
1087 off += start;
1088 vma->vm_pgoff = off >> PAGE_SHIFT;
1089 vma->vm_flags |= VM_IO | VM_RESERVED;
1090
1091#ifdef pgprot_noncached
1092 if (file->f_flags & O_DSYNC || off >= __pa(high_memory))
1093 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1094#endif
1095 if (io_remap_pfn_range(vma, vma->vm_start, off >> PAGE_SHIFT,
1096 vma->vm_end - vma->vm_start,
1097 vma->vm_page_prot))
1098 return -EAGAIN;
1099
1100 return 0;
1101 }
1102 return -ENOSYS;
1103#else
1104 return vma->vm_flags & VM_SHARED ? 0 : -ENOSYS;
1105#endif
1106}
1107
1108static const struct file_operations mtd_fops = {
1109 .owner = THIS_MODULE,
1110 .llseek = mtd_lseek,
1111 .read = mtd_read,
1112 .write = mtd_write,
1113 .unlocked_ioctl = mtd_unlocked_ioctl,
1114#ifdef CONFIG_COMPAT
1115 .compat_ioctl = mtd_compat_ioctl,
1116#endif
1117 .open = mtd_open,
1118 .release = mtd_close,
1119 .mmap = mtd_mmap,
1120#ifndef CONFIG_MMU
1121 .get_unmapped_area = mtd_get_unmapped_area,
1122#endif
1123};
1124
1125static struct dentry *mtd_inodefs_mount(struct file_system_type *fs_type,
1126 int flags, const char *dev_name, void *data)
1127{
1128 return mount_pseudo(fs_type, "mtd_inode:", NULL, NULL, MTD_INODE_FS_MAGIC);
1129}
1130
1131static struct file_system_type mtd_inodefs_type = {
1132 .name = "mtd_inodefs",
1133 .mount = mtd_inodefs_mount,
1134 .kill_sb = kill_anon_super,
1135};
1136
1137static void mtdchar_notify_add(struct mtd_info *mtd)
1138{
1139}
1140
1141static void mtdchar_notify_remove(struct mtd_info *mtd)
1142{
1143 struct inode *mtd_ino = ilookup(mtd_inode_mnt->mnt_sb, mtd->index);
1144
1145 if (mtd_ino) {
1146 /* Destroy the inode if it exists */
1147 mtd_ino->i_nlink = 0;
1148 iput(mtd_ino);
1149 }
1150}
1151
1152static struct mtd_notifier mtdchar_notifier = {
1153 .add = mtdchar_notify_add,
1154 .remove = mtdchar_notify_remove,
1155};
1156
1157static int __init init_mtdchar(void)
1158{
1159 int ret;
1160
1161 ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1162 "mtd", &mtd_fops);
1163 if (ret < 0) {
1164 pr_notice("Can't allocate major number %d for "
1165 "Memory Technology Devices.\n", MTD_CHAR_MAJOR);
1166 return ret;
1167 }
1168
1169 ret = register_filesystem(&mtd_inodefs_type);
1170 if (ret) {
1171 pr_notice("Can't register mtd_inodefs filesystem: %d\n", ret);
1172 goto err_unregister_chdev;
1173 }
1174
1175 mtd_inode_mnt = kern_mount(&mtd_inodefs_type);
1176 if (IS_ERR(mtd_inode_mnt)) {
1177 ret = PTR_ERR(mtd_inode_mnt);
1178 pr_notice("Error mounting mtd_inodefs filesystem: %d\n", ret);
1179 goto err_unregister_filesystem;
1180 }
1181 register_mtd_user(&mtdchar_notifier);
1182
1183 return ret;
1184
1185err_unregister_filesystem:
1186 unregister_filesystem(&mtd_inodefs_type);
1187err_unregister_chdev:
1188 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1189 return ret;
1190}
1191
1192static void __exit cleanup_mtdchar(void)
1193{
1194 unregister_mtd_user(&mtdchar_notifier);
1195 kern_unmount(mtd_inode_mnt);
1196 unregister_filesystem(&mtd_inodefs_type);
1197 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1198}
1199
1200module_init(init_mtdchar);
1201module_exit(cleanup_mtdchar);
1202
1203MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
1204
1205MODULE_LICENSE("GPL");
1206MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1207MODULE_DESCRIPTION("Direct character-device access to MTD devices");
1208MODULE_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);