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/major.h>
36 #include <linux/mtd/mtd.h>
37 #include <linux/mtd/partitions.h>
38 #include <linux/mtd/map.h>
39
40 #include <asm/uaccess.h>
41
42 #include "mtdcore.h"
43
44 static DEFINE_MUTEX(mtd_mutex);
45
46 /*
47 * Data structure to hold the pointer to the mtd device as well
48 * as mode information of various use cases.
49 */
50 struct mtd_file_info {
51 struct mtd_info *mtd;
52 struct inode *ino;
53 enum mtd_file_modes mode;
54 };
55
mtdchar_lseek(struct file * file,loff_t offset,int orig)56 static loff_t mtdchar_lseek(struct file *file, loff_t offset, int orig)
57 {
58 struct mtd_file_info *mfi = file->private_data;
59 return fixed_size_llseek(file, offset, orig, mfi->mtd->size);
60 }
61
62 static int count;
63 static struct vfsmount *mnt;
64 static struct file_system_type mtd_inodefs_type;
65
mtdchar_open(struct inode * inode,struct file * file)66 static int mtdchar_open(struct inode *inode, struct file *file)
67 {
68 int minor = iminor(inode);
69 int devnum = minor >> 1;
70 int ret = 0;
71 struct mtd_info *mtd;
72 struct mtd_file_info *mfi;
73 struct inode *mtd_ino;
74
75 pr_debug("MTD_open\n");
76
77 /* You can't open the RO devices RW */
78 if ((file->f_mode & FMODE_WRITE) && (minor & 1))
79 return -EACCES;
80
81 ret = simple_pin_fs(&mtd_inodefs_type, &mnt, &count);
82 if (ret)
83 return ret;
84
85 mutex_lock(&mtd_mutex);
86 mtd = get_mtd_device(NULL, devnum);
87
88 if (IS_ERR(mtd)) {
89 ret = PTR_ERR(mtd);
90 goto out;
91 }
92
93 if (mtd->type == MTD_ABSENT) {
94 ret = -ENODEV;
95 goto out1;
96 }
97
98 mtd_ino = iget_locked(mnt->mnt_sb, devnum);
99 if (!mtd_ino) {
100 ret = -ENOMEM;
101 goto out1;
102 }
103 if (mtd_ino->i_state & I_NEW) {
104 mtd_ino->i_private = mtd;
105 mtd_ino->i_mode = S_IFCHR;
106 mtd_ino->i_data.backing_dev_info = mtd->backing_dev_info;
107 unlock_new_inode(mtd_ino);
108 }
109 file->f_mapping = mtd_ino->i_mapping;
110
111 /* You can't open it RW if it's not a writeable device */
112 if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
113 ret = -EACCES;
114 goto out2;
115 }
116
117 mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
118 if (!mfi) {
119 ret = -ENOMEM;
120 goto out2;
121 }
122 mfi->ino = mtd_ino;
123 mfi->mtd = mtd;
124 file->private_data = mfi;
125 mutex_unlock(&mtd_mutex);
126 return 0;
127
128 out2:
129 iput(mtd_ino);
130 out1:
131 put_mtd_device(mtd);
132 out:
133 mutex_unlock(&mtd_mutex);
134 simple_release_fs(&mnt, &count);
135 return ret;
136 } /* mtdchar_open */
137
138 /*====================================================================*/
139
mtdchar_close(struct inode * inode,struct file * file)140 static int mtdchar_close(struct inode *inode, struct file *file)
141 {
142 struct mtd_file_info *mfi = file->private_data;
143 struct mtd_info *mtd = mfi->mtd;
144
145 pr_debug("MTD_close\n");
146
147 /* Only sync if opened RW */
148 if ((file->f_mode & FMODE_WRITE))
149 mtd_sync(mtd);
150
151 iput(mfi->ino);
152
153 put_mtd_device(mtd);
154 file->private_data = NULL;
155 kfree(mfi);
156 simple_release_fs(&mnt, &count);
157
158 return 0;
159 } /* mtdchar_close */
160
161 /* Back in June 2001, dwmw2 wrote:
162 *
163 * FIXME: This _really_ needs to die. In 2.5, we should lock the
164 * userspace buffer down and use it directly with readv/writev.
165 *
166 * The implementation below, using mtd_kmalloc_up_to, mitigates
167 * allocation failures when the system is under low-memory situations
168 * or if memory is highly fragmented at the cost of reducing the
169 * performance of the requested transfer due to a smaller buffer size.
170 *
171 * A more complex but more memory-efficient implementation based on
172 * get_user_pages and iovecs to cover extents of those pages is a
173 * longer-term goal, as intimated by dwmw2 above. However, for the
174 * write case, this requires yet more complex head and tail transfer
175 * handling when those head and tail offsets and sizes are such that
176 * alignment requirements are not met in the NAND subdriver.
177 */
178
mtdchar_read(struct file * file,char __user * buf,size_t count,loff_t * ppos)179 static ssize_t mtdchar_read(struct file *file, char __user *buf, size_t count,
180 loff_t *ppos)
181 {
182 struct mtd_file_info *mfi = file->private_data;
183 struct mtd_info *mtd = mfi->mtd;
184 size_t retlen;
185 size_t total_retlen=0;
186 int ret=0;
187 int len;
188 size_t size = count;
189 char *kbuf;
190
191 pr_debug("MTD_read\n");
192
193 if (*ppos + count > mtd->size)
194 count = mtd->size - *ppos;
195
196 if (!count)
197 return 0;
198
199 kbuf = mtd_kmalloc_up_to(mtd, &size);
200 if (!kbuf)
201 return -ENOMEM;
202
203 while (count) {
204 len = min_t(size_t, count, size);
205
206 switch (mfi->mode) {
207 case MTD_FILE_MODE_OTP_FACTORY:
208 ret = mtd_read_fact_prot_reg(mtd, *ppos, len,
209 &retlen, kbuf);
210 break;
211 case MTD_FILE_MODE_OTP_USER:
212 ret = mtd_read_user_prot_reg(mtd, *ppos, len,
213 &retlen, kbuf);
214 break;
215 case MTD_FILE_MODE_RAW:
216 {
217 struct mtd_oob_ops ops;
218
219 ops.mode = MTD_OPS_RAW;
220 ops.datbuf = kbuf;
221 ops.oobbuf = NULL;
222 ops.len = len;
223
224 ret = mtd_read_oob(mtd, *ppos, &ops);
225 retlen = ops.retlen;
226 break;
227 }
228 default:
229 ret = mtd_read(mtd, *ppos, len, &retlen, kbuf);
230 }
231 /* Nand returns -EBADMSG on ECC errors, but it returns
232 * the data. For our userspace tools it is important
233 * to dump areas with ECC errors!
234 * For kernel internal usage it also might return -EUCLEAN
235 * to signal the caller that a bitflip has occurred and has
236 * been corrected by the ECC algorithm.
237 * Userspace software which accesses NAND this way
238 * must be aware of the fact that it deals with NAND
239 */
240 if (!ret || mtd_is_bitflip_or_eccerr(ret)) {
241 *ppos += retlen;
242 if (copy_to_user(buf, kbuf, retlen)) {
243 kfree(kbuf);
244 return -EFAULT;
245 }
246 else
247 total_retlen += retlen;
248
249 count -= retlen;
250 buf += retlen;
251 if (retlen == 0)
252 count = 0;
253 }
254 else {
255 kfree(kbuf);
256 return ret;
257 }
258
259 }
260
261 kfree(kbuf);
262 return total_retlen;
263 } /* mtdchar_read */
264
mtdchar_write(struct file * file,const char __user * buf,size_t count,loff_t * ppos)265 static ssize_t mtdchar_write(struct file *file, const char __user *buf, size_t count,
266 loff_t *ppos)
267 {
268 struct mtd_file_info *mfi = file->private_data;
269 struct mtd_info *mtd = mfi->mtd;
270 size_t size = count;
271 char *kbuf;
272 size_t retlen;
273 size_t total_retlen=0;
274 int ret=0;
275 int len;
276
277 pr_debug("MTD_write\n");
278
279 if (*ppos == mtd->size)
280 return -ENOSPC;
281
282 if (*ppos + count > mtd->size)
283 count = mtd->size - *ppos;
284
285 if (!count)
286 return 0;
287
288 kbuf = mtd_kmalloc_up_to(mtd, &size);
289 if (!kbuf)
290 return -ENOMEM;
291
292 while (count) {
293 len = min_t(size_t, count, size);
294
295 if (copy_from_user(kbuf, buf, len)) {
296 kfree(kbuf);
297 return -EFAULT;
298 }
299
300 switch (mfi->mode) {
301 case MTD_FILE_MODE_OTP_FACTORY:
302 ret = -EROFS;
303 break;
304 case MTD_FILE_MODE_OTP_USER:
305 ret = mtd_write_user_prot_reg(mtd, *ppos, len,
306 &retlen, kbuf);
307 break;
308
309 case MTD_FILE_MODE_RAW:
310 {
311 struct mtd_oob_ops ops;
312
313 ops.mode = MTD_OPS_RAW;
314 ops.datbuf = kbuf;
315 ops.oobbuf = NULL;
316 ops.ooboffs = 0;
317 ops.len = len;
318
319 ret = mtd_write_oob(mtd, *ppos, &ops);
320 retlen = ops.retlen;
321 break;
322 }
323
324 default:
325 ret = mtd_write(mtd, *ppos, len, &retlen, kbuf);
326 }
327
328 /*
329 * Return -ENOSPC only if no data could be written at all.
330 * Otherwise just return the number of bytes that actually
331 * have been written.
332 */
333 if ((ret == -ENOSPC) && (total_retlen))
334 break;
335
336 if (!ret) {
337 *ppos += retlen;
338 total_retlen += retlen;
339 count -= retlen;
340 buf += retlen;
341 }
342 else {
343 kfree(kbuf);
344 return ret;
345 }
346 }
347
348 kfree(kbuf);
349 return total_retlen;
350 } /* mtdchar_write */
351
352 /*======================================================================
353
354 IOCTL calls for getting device parameters.
355
356 ======================================================================*/
mtdchar_erase_callback(struct erase_info * instr)357 static void mtdchar_erase_callback (struct erase_info *instr)
358 {
359 wake_up((wait_queue_head_t *)instr->priv);
360 }
361
otp_select_filemode(struct mtd_file_info * mfi,int mode)362 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
363 {
364 struct mtd_info *mtd = mfi->mtd;
365 size_t retlen;
366
367 switch (mode) {
368 case MTD_OTP_FACTORY:
369 if (mtd_read_fact_prot_reg(mtd, -1, 0, &retlen, NULL) ==
370 -EOPNOTSUPP)
371 return -EOPNOTSUPP;
372
373 mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
374 break;
375 case MTD_OTP_USER:
376 if (mtd_read_user_prot_reg(mtd, -1, 0, &retlen, NULL) ==
377 -EOPNOTSUPP)
378 return -EOPNOTSUPP;
379
380 mfi->mode = MTD_FILE_MODE_OTP_USER;
381 break;
382 case MTD_OTP_OFF:
383 mfi->mode = MTD_FILE_MODE_NORMAL;
384 break;
385 default:
386 return -EINVAL;
387 }
388
389 return 0;
390 }
391
mtdchar_writeoob(struct file * file,struct mtd_info * mtd,uint64_t start,uint32_t length,void __user * ptr,uint32_t __user * retp)392 static int mtdchar_writeoob(struct file *file, struct mtd_info *mtd,
393 uint64_t start, uint32_t length, void __user *ptr,
394 uint32_t __user *retp)
395 {
396 struct mtd_file_info *mfi = file->private_data;
397 struct mtd_oob_ops ops;
398 uint32_t retlen;
399 int ret = 0;
400
401 if (!(file->f_mode & FMODE_WRITE))
402 return -EPERM;
403
404 if (length > 4096)
405 return -EINVAL;
406
407 if (!mtd->_write_oob)
408 ret = -EOPNOTSUPP;
409 else
410 ret = access_ok(VERIFY_READ, ptr, length) ? 0 : -EFAULT;
411
412 if (ret)
413 return ret;
414
415 ops.ooblen = length;
416 ops.ooboffs = start & (mtd->writesize - 1);
417 ops.datbuf = NULL;
418 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
419 MTD_OPS_PLACE_OOB;
420
421 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
422 return -EINVAL;
423
424 ops.oobbuf = memdup_user(ptr, length);
425 if (IS_ERR(ops.oobbuf))
426 return PTR_ERR(ops.oobbuf);
427
428 start &= ~((uint64_t)mtd->writesize - 1);
429 ret = mtd_write_oob(mtd, start, &ops);
430
431 if (ops.oobretlen > 0xFFFFFFFFU)
432 ret = -EOVERFLOW;
433 retlen = ops.oobretlen;
434 if (copy_to_user(retp, &retlen, sizeof(length)))
435 ret = -EFAULT;
436
437 kfree(ops.oobbuf);
438 return ret;
439 }
440
mtdchar_readoob(struct file * file,struct mtd_info * mtd,uint64_t start,uint32_t length,void __user * ptr,uint32_t __user * retp)441 static int mtdchar_readoob(struct file *file, struct mtd_info *mtd,
442 uint64_t start, uint32_t length, void __user *ptr,
443 uint32_t __user *retp)
444 {
445 struct mtd_file_info *mfi = file->private_data;
446 struct mtd_oob_ops ops;
447 int ret = 0;
448
449 if (length > 4096)
450 return -EINVAL;
451
452 if (!access_ok(VERIFY_WRITE, ptr, length))
453 return -EFAULT;
454
455 ops.ooblen = length;
456 ops.ooboffs = start & (mtd->writesize - 1);
457 ops.datbuf = NULL;
458 ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
459 MTD_OPS_PLACE_OOB;
460
461 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
462 return -EINVAL;
463
464 ops.oobbuf = kmalloc(length, GFP_KERNEL);
465 if (!ops.oobbuf)
466 return -ENOMEM;
467
468 start &= ~((uint64_t)mtd->writesize - 1);
469 ret = mtd_read_oob(mtd, start, &ops);
470
471 if (put_user(ops.oobretlen, retp))
472 ret = -EFAULT;
473 else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
474 ops.oobretlen))
475 ret = -EFAULT;
476
477 kfree(ops.oobbuf);
478
479 /*
480 * NAND returns -EBADMSG on ECC errors, but it returns the OOB
481 * data. For our userspace tools it is important to dump areas
482 * with ECC errors!
483 * For kernel internal usage it also might return -EUCLEAN
484 * to signal the caller that a bitflip has occured and has
485 * been corrected by the ECC algorithm.
486 *
487 * Note: currently the standard NAND function, nand_read_oob_std,
488 * does not calculate ECC for the OOB area, so do not rely on
489 * this behavior unless you have replaced it with your own.
490 */
491 if (mtd_is_bitflip_or_eccerr(ret))
492 return 0;
493
494 return ret;
495 }
496
497 /*
498 * Copies (and truncates, if necessary) data from the larger struct,
499 * nand_ecclayout, to the smaller, deprecated layout struct,
500 * nand_ecclayout_user. This is necessary only to support the deprecated
501 * API ioctl ECCGETLAYOUT while allowing all new functionality to use
502 * nand_ecclayout flexibly (i.e. the struct may change size in new
503 * releases without requiring major rewrites).
504 */
shrink_ecclayout(const struct nand_ecclayout * from,struct nand_ecclayout_user * to)505 static int shrink_ecclayout(const struct nand_ecclayout *from,
506 struct nand_ecclayout_user *to)
507 {
508 int i;
509
510 if (!from || !to)
511 return -EINVAL;
512
513 memset(to, 0, sizeof(*to));
514
515 to->eccbytes = min((int)from->eccbytes, MTD_MAX_ECCPOS_ENTRIES);
516 for (i = 0; i < to->eccbytes; i++)
517 to->eccpos[i] = from->eccpos[i];
518
519 for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
520 if (from->oobfree[i].length == 0 &&
521 from->oobfree[i].offset == 0)
522 break;
523 to->oobavail += from->oobfree[i].length;
524 to->oobfree[i] = from->oobfree[i];
525 }
526
527 return 0;
528 }
529
mtdchar_blkpg_ioctl(struct mtd_info * mtd,struct blkpg_ioctl_arg __user * arg)530 static int mtdchar_blkpg_ioctl(struct mtd_info *mtd,
531 struct blkpg_ioctl_arg __user *arg)
532 {
533 struct blkpg_ioctl_arg a;
534 struct blkpg_partition p;
535
536 if (!capable(CAP_SYS_ADMIN))
537 return -EPERM;
538
539 if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
540 return -EFAULT;
541
542 if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
543 return -EFAULT;
544
545 switch (a.op) {
546 case BLKPG_ADD_PARTITION:
547
548 /* Only master mtd device must be used to add partitions */
549 if (mtd_is_partition(mtd))
550 return -EINVAL;
551
552 /* Sanitize user input */
553 p.devname[BLKPG_DEVNAMELTH - 1] = '\0';
554
555 return mtd_add_partition(mtd, p.devname, p.start, p.length);
556
557 case BLKPG_DEL_PARTITION:
558
559 if (p.pno < 0)
560 return -EINVAL;
561
562 return mtd_del_partition(mtd, p.pno);
563
564 default:
565 return -EINVAL;
566 }
567 }
568
mtdchar_write_ioctl(struct mtd_info * mtd,struct mtd_write_req __user * argp)569 static int mtdchar_write_ioctl(struct mtd_info *mtd,
570 struct mtd_write_req __user *argp)
571 {
572 struct mtd_write_req req;
573 struct mtd_oob_ops ops;
574 const void __user *usr_data, *usr_oob;
575 int ret;
576
577 if (copy_from_user(&req, argp, sizeof(req)))
578 return -EFAULT;
579
580 usr_data = (const void __user *)(uintptr_t)req.usr_data;
581 usr_oob = (const void __user *)(uintptr_t)req.usr_oob;
582 if (!access_ok(VERIFY_READ, usr_data, req.len) ||
583 !access_ok(VERIFY_READ, usr_oob, req.ooblen))
584 return -EFAULT;
585
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 if (usr_data) {
595 ops.datbuf = memdup_user(usr_data, ops.len);
596 if (IS_ERR(ops.datbuf))
597 return PTR_ERR(ops.datbuf);
598 } else {
599 ops.datbuf = NULL;
600 }
601
602 if (usr_oob) {
603 ops.oobbuf = memdup_user(usr_oob, ops.ooblen);
604 if (IS_ERR(ops.oobbuf)) {
605 kfree(ops.datbuf);
606 return PTR_ERR(ops.oobbuf);
607 }
608 } else {
609 ops.oobbuf = NULL;
610 }
611
612 ret = mtd_write_oob(mtd, (loff_t)req.start, &ops);
613
614 kfree(ops.datbuf);
615 kfree(ops.oobbuf);
616
617 return ret;
618 }
619
mtdchar_ioctl(struct file * file,u_int cmd,u_long arg)620 static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
621 {
622 struct mtd_file_info *mfi = file->private_data;
623 struct mtd_info *mtd = mfi->mtd;
624 void __user *argp = (void __user *)arg;
625 int ret = 0;
626 u_long size;
627 struct mtd_info_user info;
628
629 pr_debug("MTD_ioctl\n");
630
631 size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
632 if (cmd & IOC_IN) {
633 if (!access_ok(VERIFY_READ, argp, size))
634 return -EFAULT;
635 }
636 if (cmd & IOC_OUT) {
637 if (!access_ok(VERIFY_WRITE, argp, size))
638 return -EFAULT;
639 }
640
641 switch (cmd) {
642 case MEMGETREGIONCOUNT:
643 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
644 return -EFAULT;
645 break;
646
647 case MEMGETREGIONINFO:
648 {
649 uint32_t ur_idx;
650 struct mtd_erase_region_info *kr;
651 struct region_info_user __user *ur = argp;
652
653 if (get_user(ur_idx, &(ur->regionindex)))
654 return -EFAULT;
655
656 if (ur_idx >= mtd->numeraseregions)
657 return -EINVAL;
658
659 kr = &(mtd->eraseregions[ur_idx]);
660
661 if (put_user(kr->offset, &(ur->offset))
662 || put_user(kr->erasesize, &(ur->erasesize))
663 || put_user(kr->numblocks, &(ur->numblocks)))
664 return -EFAULT;
665
666 break;
667 }
668
669 case MEMGETINFO:
670 memset(&info, 0, sizeof(info));
671 info.type = mtd->type;
672 info.flags = mtd->flags;
673 info.size = mtd->size;
674 info.erasesize = mtd->erasesize;
675 info.writesize = mtd->writesize;
676 info.oobsize = mtd->oobsize;
677 /* The below field is obsolete */
678 info.padding = 0;
679 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
680 return -EFAULT;
681 break;
682
683 case MEMERASE:
684 case MEMERASE64:
685 {
686 struct erase_info *erase;
687
688 if(!(file->f_mode & FMODE_WRITE))
689 return -EPERM;
690
691 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
692 if (!erase)
693 ret = -ENOMEM;
694 else {
695 wait_queue_head_t waitq;
696 DECLARE_WAITQUEUE(wait, current);
697
698 init_waitqueue_head(&waitq);
699
700 if (cmd == MEMERASE64) {
701 struct erase_info_user64 einfo64;
702
703 if (copy_from_user(&einfo64, argp,
704 sizeof(struct erase_info_user64))) {
705 kfree(erase);
706 return -EFAULT;
707 }
708 erase->addr = einfo64.start;
709 erase->len = einfo64.length;
710 } else {
711 struct erase_info_user einfo32;
712
713 if (copy_from_user(&einfo32, argp,
714 sizeof(struct erase_info_user))) {
715 kfree(erase);
716 return -EFAULT;
717 }
718 erase->addr = einfo32.start;
719 erase->len = einfo32.length;
720 }
721 erase->mtd = mtd;
722 erase->callback = mtdchar_erase_callback;
723 erase->priv = (unsigned long)&waitq;
724
725 /*
726 FIXME: Allow INTERRUPTIBLE. Which means
727 not having the wait_queue head on the stack.
728
729 If the wq_head is on the stack, and we
730 leave because we got interrupted, then the
731 wq_head is no longer there when the
732 callback routine tries to wake us up.
733 */
734 ret = mtd_erase(mtd, erase);
735 if (!ret) {
736 set_current_state(TASK_UNINTERRUPTIBLE);
737 add_wait_queue(&waitq, &wait);
738 if (erase->state != MTD_ERASE_DONE &&
739 erase->state != MTD_ERASE_FAILED)
740 schedule();
741 remove_wait_queue(&waitq, &wait);
742 set_current_state(TASK_RUNNING);
743
744 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
745 }
746 kfree(erase);
747 }
748 break;
749 }
750
751 case MEMWRITEOOB:
752 {
753 struct mtd_oob_buf buf;
754 struct mtd_oob_buf __user *buf_user = argp;
755
756 /* NOTE: writes return length to buf_user->length */
757 if (copy_from_user(&buf, argp, sizeof(buf)))
758 ret = -EFAULT;
759 else
760 ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
761 buf.ptr, &buf_user->length);
762 break;
763 }
764
765 case MEMREADOOB:
766 {
767 struct mtd_oob_buf buf;
768 struct mtd_oob_buf __user *buf_user = argp;
769
770 /* NOTE: writes return length to buf_user->start */
771 if (copy_from_user(&buf, argp, sizeof(buf)))
772 ret = -EFAULT;
773 else
774 ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
775 buf.ptr, &buf_user->start);
776 break;
777 }
778
779 case MEMWRITEOOB64:
780 {
781 struct mtd_oob_buf64 buf;
782 struct mtd_oob_buf64 __user *buf_user = argp;
783
784 if (copy_from_user(&buf, argp, sizeof(buf)))
785 ret = -EFAULT;
786 else
787 ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
788 (void __user *)(uintptr_t)buf.usr_ptr,
789 &buf_user->length);
790 break;
791 }
792
793 case MEMREADOOB64:
794 {
795 struct mtd_oob_buf64 buf;
796 struct mtd_oob_buf64 __user *buf_user = argp;
797
798 if (copy_from_user(&buf, argp, sizeof(buf)))
799 ret = -EFAULT;
800 else
801 ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
802 (void __user *)(uintptr_t)buf.usr_ptr,
803 &buf_user->length);
804 break;
805 }
806
807 case MEMWRITE:
808 {
809 ret = mtdchar_write_ioctl(mtd,
810 (struct mtd_write_req __user *)arg);
811 break;
812 }
813
814 case MEMLOCK:
815 {
816 struct erase_info_user einfo;
817
818 if (copy_from_user(&einfo, argp, sizeof(einfo)))
819 return -EFAULT;
820
821 ret = mtd_lock(mtd, einfo.start, einfo.length);
822 break;
823 }
824
825 case MEMUNLOCK:
826 {
827 struct erase_info_user einfo;
828
829 if (copy_from_user(&einfo, argp, sizeof(einfo)))
830 return -EFAULT;
831
832 ret = mtd_unlock(mtd, einfo.start, einfo.length);
833 break;
834 }
835
836 case MEMISLOCKED:
837 {
838 struct erase_info_user einfo;
839
840 if (copy_from_user(&einfo, argp, sizeof(einfo)))
841 return -EFAULT;
842
843 ret = mtd_is_locked(mtd, einfo.start, einfo.length);
844 break;
845 }
846
847 /* Legacy interface */
848 case MEMGETOOBSEL:
849 {
850 struct nand_oobinfo oi;
851
852 if (!mtd->ecclayout)
853 return -EOPNOTSUPP;
854 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
855 return -EINVAL;
856
857 oi.useecc = MTD_NANDECC_AUTOPLACE;
858 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
859 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
860 sizeof(oi.oobfree));
861 oi.eccbytes = mtd->ecclayout->eccbytes;
862
863 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
864 return -EFAULT;
865 break;
866 }
867
868 case MEMGETBADBLOCK:
869 {
870 loff_t offs;
871
872 if (copy_from_user(&offs, argp, sizeof(loff_t)))
873 return -EFAULT;
874 return mtd_block_isbad(mtd, offs);
875 break;
876 }
877
878 case MEMSETBADBLOCK:
879 {
880 loff_t offs;
881
882 if (copy_from_user(&offs, argp, sizeof(loff_t)))
883 return -EFAULT;
884 return mtd_block_markbad(mtd, offs);
885 break;
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 {
935 struct otp_info oinfo;
936
937 if (mfi->mode != MTD_FILE_MODE_OTP_USER)
938 return -EINVAL;
939 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
940 return -EFAULT;
941 ret = mtd_lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
942 break;
943 }
944
945 /* This ioctl is being deprecated - it truncates the ECC layout */
946 case ECCGETLAYOUT:
947 {
948 struct nand_ecclayout_user *usrlay;
949
950 if (!mtd->ecclayout)
951 return -EOPNOTSUPP;
952
953 usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
954 if (!usrlay)
955 return -ENOMEM;
956
957 shrink_ecclayout(mtd->ecclayout, usrlay);
958
959 if (copy_to_user(argp, usrlay, sizeof(*usrlay)))
960 ret = -EFAULT;
961 kfree(usrlay);
962 break;
963 }
964
965 case ECCGETSTATS:
966 {
967 if (copy_to_user(argp, &mtd->ecc_stats,
968 sizeof(struct mtd_ecc_stats)))
969 return -EFAULT;
970 break;
971 }
972
973 case MTDFILEMODE:
974 {
975 mfi->mode = 0;
976
977 switch(arg) {
978 case MTD_FILE_MODE_OTP_FACTORY:
979 case MTD_FILE_MODE_OTP_USER:
980 ret = otp_select_filemode(mfi, arg);
981 break;
982
983 case MTD_FILE_MODE_RAW:
984 if (!mtd_has_oob(mtd))
985 return -EOPNOTSUPP;
986 mfi->mode = arg;
987
988 case MTD_FILE_MODE_NORMAL:
989 break;
990 default:
991 ret = -EINVAL;
992 }
993 file->f_pos = 0;
994 break;
995 }
996
997 case BLKPG:
998 {
999 ret = mtdchar_blkpg_ioctl(mtd,
1000 (struct blkpg_ioctl_arg __user *)arg);
1001 break;
1002 }
1003
1004 case BLKRRPART:
1005 {
1006 /* No reread partition feature. Just return ok */
1007 ret = 0;
1008 break;
1009 }
1010
1011 default:
1012 ret = -ENOTTY;
1013 }
1014
1015 return ret;
1016 } /* memory_ioctl */
1017
mtdchar_unlocked_ioctl(struct file * file,u_int cmd,u_long arg)1018 static long mtdchar_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
1019 {
1020 int ret;
1021
1022 mutex_lock(&mtd_mutex);
1023 ret = mtdchar_ioctl(file, cmd, arg);
1024 mutex_unlock(&mtd_mutex);
1025
1026 return ret;
1027 }
1028
1029 #ifdef CONFIG_COMPAT
1030
1031 struct mtd_oob_buf32 {
1032 u_int32_t start;
1033 u_int32_t length;
1034 compat_caddr_t ptr; /* unsigned char* */
1035 };
1036
1037 #define MEMWRITEOOB32 _IOWR('M', 3, struct mtd_oob_buf32)
1038 #define MEMREADOOB32 _IOWR('M', 4, struct mtd_oob_buf32)
1039
mtdchar_compat_ioctl(struct file * file,unsigned int cmd,unsigned long arg)1040 static long mtdchar_compat_ioctl(struct file *file, unsigned int cmd,
1041 unsigned long arg)
1042 {
1043 struct mtd_file_info *mfi = file->private_data;
1044 struct mtd_info *mtd = mfi->mtd;
1045 void __user *argp = compat_ptr(arg);
1046 int ret = 0;
1047
1048 mutex_lock(&mtd_mutex);
1049
1050 switch (cmd) {
1051 case MEMWRITEOOB32:
1052 {
1053 struct mtd_oob_buf32 buf;
1054 struct mtd_oob_buf32 __user *buf_user = argp;
1055
1056 if (copy_from_user(&buf, argp, sizeof(buf)))
1057 ret = -EFAULT;
1058 else
1059 ret = mtdchar_writeoob(file, mtd, buf.start,
1060 buf.length, compat_ptr(buf.ptr),
1061 &buf_user->length);
1062 break;
1063 }
1064
1065 case MEMREADOOB32:
1066 {
1067 struct mtd_oob_buf32 buf;
1068 struct mtd_oob_buf32 __user *buf_user = argp;
1069
1070 /* NOTE: writes return length to buf->start */
1071 if (copy_from_user(&buf, argp, sizeof(buf)))
1072 ret = -EFAULT;
1073 else
1074 ret = mtdchar_readoob(file, mtd, buf.start,
1075 buf.length, compat_ptr(buf.ptr),
1076 &buf_user->start);
1077 break;
1078 }
1079 default:
1080 ret = mtdchar_ioctl(file, cmd, (unsigned long)argp);
1081 }
1082
1083 mutex_unlock(&mtd_mutex);
1084
1085 return ret;
1086 }
1087
1088 #endif /* CONFIG_COMPAT */
1089
1090 /*
1091 * try to determine where a shared mapping can be made
1092 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
1093 * mappings)
1094 */
1095 #ifndef CONFIG_MMU
mtdchar_get_unmapped_area(struct file * file,unsigned long addr,unsigned long len,unsigned long pgoff,unsigned long flags)1096 static unsigned long mtdchar_get_unmapped_area(struct file *file,
1097 unsigned long addr,
1098 unsigned long len,
1099 unsigned long pgoff,
1100 unsigned long flags)
1101 {
1102 struct mtd_file_info *mfi = file->private_data;
1103 struct mtd_info *mtd = mfi->mtd;
1104 unsigned long offset;
1105 int ret;
1106
1107 if (addr != 0)
1108 return (unsigned long) -EINVAL;
1109
1110 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
1111 return (unsigned long) -EINVAL;
1112
1113 offset = pgoff << PAGE_SHIFT;
1114 if (offset > mtd->size - len)
1115 return (unsigned long) -EINVAL;
1116
1117 ret = mtd_get_unmapped_area(mtd, len, offset, flags);
1118 return ret == -EOPNOTSUPP ? -ENODEV : ret;
1119 }
1120 #endif
1121
1122 /*
1123 * set up a mapping for shared memory segments
1124 */
mtdchar_mmap(struct file * file,struct vm_area_struct * vma)1125 static int mtdchar_mmap(struct file *file, struct vm_area_struct *vma)
1126 {
1127 #ifdef CONFIG_MMU
1128 struct mtd_file_info *mfi = file->private_data;
1129 struct mtd_info *mtd = mfi->mtd;
1130 struct map_info *map = mtd->priv;
1131
1132 /* This is broken because it assumes the MTD device is map-based
1133 and that mtd->priv is a valid struct map_info. It should be
1134 replaced with something that uses the mtd_get_unmapped_area()
1135 operation properly. */
1136 if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
1137 #ifdef pgprot_noncached
1138 if (file->f_flags & O_DSYNC || map->phys >= __pa(high_memory))
1139 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1140 #endif
1141 return vm_iomap_memory(vma, map->phys, map->size);
1142 }
1143 return -ENODEV;
1144 #else
1145 return vma->vm_flags & VM_SHARED ? 0 : -EACCES;
1146 #endif
1147 }
1148
1149 static const struct file_operations mtd_fops = {
1150 .owner = THIS_MODULE,
1151 .llseek = mtdchar_lseek,
1152 .read = mtdchar_read,
1153 .write = mtdchar_write,
1154 .unlocked_ioctl = mtdchar_unlocked_ioctl,
1155 #ifdef CONFIG_COMPAT
1156 .compat_ioctl = mtdchar_compat_ioctl,
1157 #endif
1158 .open = mtdchar_open,
1159 .release = mtdchar_close,
1160 .mmap = mtdchar_mmap,
1161 #ifndef CONFIG_MMU
1162 .get_unmapped_area = mtdchar_get_unmapped_area,
1163 #endif
1164 };
1165
1166 static const struct super_operations mtd_ops = {
1167 .drop_inode = generic_delete_inode,
1168 .statfs = simple_statfs,
1169 };
1170
mtd_inodefs_mount(struct file_system_type * fs_type,int flags,const char * dev_name,void * data)1171 static struct dentry *mtd_inodefs_mount(struct file_system_type *fs_type,
1172 int flags, const char *dev_name, void *data)
1173 {
1174 return mount_pseudo(fs_type, "mtd_inode:", &mtd_ops, NULL, MTD_INODE_FS_MAGIC);
1175 }
1176
1177 static struct file_system_type mtd_inodefs_type = {
1178 .name = "mtd_inodefs",
1179 .mount = mtd_inodefs_mount,
1180 .kill_sb = kill_anon_super,
1181 };
1182 MODULE_ALIAS_FS("mtd_inodefs");
1183
init_mtdchar(void)1184 int __init init_mtdchar(void)
1185 {
1186 int ret;
1187
1188 ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1189 "mtd", &mtd_fops);
1190 if (ret < 0) {
1191 pr_err("Can't allocate major number %d for MTD\n",
1192 MTD_CHAR_MAJOR);
1193 return ret;
1194 }
1195
1196 ret = register_filesystem(&mtd_inodefs_type);
1197 if (ret) {
1198 pr_err("Can't register mtd_inodefs filesystem, error %d\n",
1199 ret);
1200 goto err_unregister_chdev;
1201 }
1202
1203 return ret;
1204
1205 err_unregister_chdev:
1206 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1207 return ret;
1208 }
1209
cleanup_mtdchar(void)1210 void __exit cleanup_mtdchar(void)
1211 {
1212 unregister_filesystem(&mtd_inodefs_type);
1213 __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1214 }
1215
1216 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
1217