Merge branch 'bkl/ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic...
[linux-2.6.git] / drivers / mtd / mtdchar.c
1 /*
2  * Character-device access to raw MTD devices.
3  *
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/smp_lock.h>
16 #include <linux/backing-dev.h>
17 #include <linux/compat.h>
18 #include <linux/mount.h>
19
20 #include <linux/mtd/mtd.h>
21 #include <linux/mtd/compatmac.h>
22
23 #include <asm/uaccess.h>
24
25 #define MTD_INODE_FS_MAGIC 0x11307854
26 static struct vfsmount *mtd_inode_mnt __read_mostly;
27
28 /*
29  * Data structure to hold the pointer to the mtd device as well
30  * as mode information ofr various use cases.
31  */
32 struct mtd_file_info {
33         struct mtd_info *mtd;
34         struct inode *ino;
35         enum mtd_file_modes mode;
36 };
37
38 static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
39 {
40         struct mtd_file_info *mfi = file->private_data;
41         struct mtd_info *mtd = mfi->mtd;
42
43         switch (orig) {
44         case SEEK_SET:
45                 break;
46         case SEEK_CUR:
47                 offset += file->f_pos;
48                 break;
49         case SEEK_END:
50                 offset += mtd->size;
51                 break;
52         default:
53                 return -EINVAL;
54         }
55
56         if (offset >= 0 && offset <= mtd->size)
57                 return file->f_pos = offset;
58
59         return -EINVAL;
60 }
61
62
63
64 static int mtd_open(struct inode *inode, struct file *file)
65 {
66         int minor = iminor(inode);
67         int devnum = minor >> 1;
68         int ret = 0;
69         struct mtd_info *mtd;
70         struct mtd_file_info *mfi;
71         struct inode *mtd_ino;
72
73         DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
74
75         /* You can't open the RO devices RW */
76         if ((file->f_mode & FMODE_WRITE) && (minor & 1))
77                 return -EACCES;
78
79         lock_kernel();
80         mtd = get_mtd_device(NULL, devnum);
81
82         if (IS_ERR(mtd)) {
83                 ret = PTR_ERR(mtd);
84                 goto out;
85         }
86
87         if (mtd->type == MTD_ABSENT) {
88                 put_mtd_device(mtd);
89                 ret = -ENODEV;
90                 goto out;
91         }
92
93         mtd_ino = iget_locked(mtd_inode_mnt->mnt_sb, devnum);
94         if (!mtd_ino) {
95                 put_mtd_device(mtd);
96                 ret = -ENOMEM;
97                 goto out;
98         }
99         if (mtd_ino->i_state & I_NEW) {
100                 mtd_ino->i_private = mtd;
101                 mtd_ino->i_mode = S_IFCHR;
102                 mtd_ino->i_data.backing_dev_info = mtd->backing_dev_info;
103                 unlock_new_inode(mtd_ino);
104         }
105         file->f_mapping = mtd_ino->i_mapping;
106
107         /* You can't open it RW if it's not a writeable device */
108         if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
109                 iput(mtd_ino);
110                 put_mtd_device(mtd);
111                 ret = -EACCES;
112                 goto out;
113         }
114
115         mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
116         if (!mfi) {
117                 iput(mtd_ino);
118                 put_mtd_device(mtd);
119                 ret = -ENOMEM;
120                 goto out;
121         }
122         mfi->ino = mtd_ino;
123         mfi->mtd = mtd;
124         file->private_data = mfi;
125
126 out:
127         unlock_kernel();
128         return ret;
129 } /* mtd_open */
130
131 /*====================================================================*/
132
133 static int mtd_close(struct inode *inode, struct file *file)
134 {
135         struct mtd_file_info *mfi = file->private_data;
136         struct mtd_info *mtd = mfi->mtd;
137
138         DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
139
140         /* Only sync if opened RW */
141         if ((file->f_mode & FMODE_WRITE) && mtd->sync)
142                 mtd->sync(mtd);
143
144         iput(mfi->ino);
145
146         put_mtd_device(mtd);
147         file->private_data = NULL;
148         kfree(mfi);
149
150         return 0;
151 } /* mtd_close */
152
153 /* FIXME: This _really_ needs to die. In 2.5, we should lock the
154    userspace buffer down and use it directly with readv/writev.
155 */
156 #define MAX_KMALLOC_SIZE 0x20000
157
158 static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
159 {
160         struct mtd_file_info *mfi = file->private_data;
161         struct mtd_info *mtd = mfi->mtd;
162         size_t retlen=0;
163         size_t total_retlen=0;
164         int ret=0;
165         int len;
166         char *kbuf;
167
168         DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
169
170         if (*ppos + count > mtd->size)
171                 count = mtd->size - *ppos;
172
173         if (!count)
174                 return 0;
175
176         /* FIXME: Use kiovec in 2.5 to lock down the user's buffers
177            and pass them directly to the MTD functions */
178
179         if (count > MAX_KMALLOC_SIZE)
180                 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
181         else
182                 kbuf=kmalloc(count, GFP_KERNEL);
183
184         if (!kbuf)
185                 return -ENOMEM;
186
187         while (count) {
188
189                 if (count > MAX_KMALLOC_SIZE)
190                         len = MAX_KMALLOC_SIZE;
191                 else
192                         len = count;
193
194                 switch (mfi->mode) {
195                 case MTD_MODE_OTP_FACTORY:
196                         ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
197                         break;
198                 case MTD_MODE_OTP_USER:
199                         ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
200                         break;
201                 case MTD_MODE_RAW:
202                 {
203                         struct mtd_oob_ops ops;
204
205                         ops.mode = MTD_OOB_RAW;
206                         ops.datbuf = kbuf;
207                         ops.oobbuf = NULL;
208                         ops.len = len;
209
210                         ret = mtd->read_oob(mtd, *ppos, &ops);
211                         retlen = ops.retlen;
212                         break;
213                 }
214                 default:
215                         ret = mtd->read(mtd, *ppos, len, &retlen, kbuf);
216                 }
217                 /* Nand returns -EBADMSG on ecc errors, but it returns
218                  * the data. For our userspace tools it is important
219                  * to dump areas with ecc errors !
220                  * For kernel internal usage it also might return -EUCLEAN
221                  * to signal the caller that a bitflip has occured and has
222                  * been corrected by the ECC algorithm.
223                  * Userspace software which accesses NAND this way
224                  * must be aware of the fact that it deals with NAND
225                  */
226                 if (!ret || (ret == -EUCLEAN) || (ret == -EBADMSG)) {
227                         *ppos += retlen;
228                         if (copy_to_user(buf, kbuf, retlen)) {
229                                 kfree(kbuf);
230                                 return -EFAULT;
231                         }
232                         else
233                                 total_retlen += retlen;
234
235                         count -= retlen;
236                         buf += retlen;
237                         if (retlen == 0)
238                                 count = 0;
239                 }
240                 else {
241                         kfree(kbuf);
242                         return ret;
243                 }
244
245         }
246
247         kfree(kbuf);
248         return total_retlen;
249 } /* mtd_read */
250
251 static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
252 {
253         struct mtd_file_info *mfi = file->private_data;
254         struct mtd_info *mtd = mfi->mtd;
255         char *kbuf;
256         size_t retlen;
257         size_t total_retlen=0;
258         int ret=0;
259         int len;
260
261         DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
262
263         if (*ppos == mtd->size)
264                 return -ENOSPC;
265
266         if (*ppos + count > mtd->size)
267                 count = mtd->size - *ppos;
268
269         if (!count)
270                 return 0;
271
272         if (count > MAX_KMALLOC_SIZE)
273                 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
274         else
275                 kbuf=kmalloc(count, GFP_KERNEL);
276
277         if (!kbuf)
278                 return -ENOMEM;
279
280         while (count) {
281
282                 if (count > MAX_KMALLOC_SIZE)
283                         len = MAX_KMALLOC_SIZE;
284                 else
285                         len = count;
286
287                 if (copy_from_user(kbuf, buf, len)) {
288                         kfree(kbuf);
289                         return -EFAULT;
290                 }
291
292                 switch (mfi->mode) {
293                 case MTD_MODE_OTP_FACTORY:
294                         ret = -EROFS;
295                         break;
296                 case MTD_MODE_OTP_USER:
297                         if (!mtd->write_user_prot_reg) {
298                                 ret = -EOPNOTSUPP;
299                                 break;
300                         }
301                         ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
302                         break;
303
304                 case MTD_MODE_RAW:
305                 {
306                         struct mtd_oob_ops ops;
307
308                         ops.mode = MTD_OOB_RAW;
309                         ops.datbuf = kbuf;
310                         ops.oobbuf = NULL;
311                         ops.len = len;
312
313                         ret = mtd->write_oob(mtd, *ppos, &ops);
314                         retlen = ops.retlen;
315                         break;
316                 }
317
318                 default:
319                         ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
320                 }
321                 if (!ret) {
322                         *ppos += retlen;
323                         total_retlen += retlen;
324                         count -= retlen;
325                         buf += retlen;
326                 }
327                 else {
328                         kfree(kbuf);
329                         return ret;
330                 }
331         }
332
333         kfree(kbuf);
334         return total_retlen;
335 } /* mtd_write */
336
337 /*======================================================================
338
339     IOCTL calls for getting device parameters.
340
341 ======================================================================*/
342 static void mtdchar_erase_callback (struct erase_info *instr)
343 {
344         wake_up((wait_queue_head_t *)instr->priv);
345 }
346
347 #ifdef CONFIG_HAVE_MTD_OTP
348 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
349 {
350         struct mtd_info *mtd = mfi->mtd;
351         int ret = 0;
352
353         switch (mode) {
354         case MTD_OTP_FACTORY:
355                 if (!mtd->read_fact_prot_reg)
356                         ret = -EOPNOTSUPP;
357                 else
358                         mfi->mode = MTD_MODE_OTP_FACTORY;
359                 break;
360         case MTD_OTP_USER:
361                 if (!mtd->read_fact_prot_reg)
362                         ret = -EOPNOTSUPP;
363                 else
364                         mfi->mode = MTD_MODE_OTP_USER;
365                 break;
366         default:
367                 ret = -EINVAL;
368         case MTD_OTP_OFF:
369                 break;
370         }
371         return ret;
372 }
373 #else
374 # define otp_select_filemode(f,m)       -EOPNOTSUPP
375 #endif
376
377 static int mtd_do_writeoob(struct file *file, struct mtd_info *mtd,
378         uint64_t start, uint32_t length, void __user *ptr,
379         uint32_t __user *retp)
380 {
381         struct mtd_oob_ops ops;
382         uint32_t retlen;
383         int ret = 0;
384
385         if (!(file->f_mode & FMODE_WRITE))
386                 return -EPERM;
387
388         if (length > 4096)
389                 return -EINVAL;
390
391         if (!mtd->write_oob)
392                 ret = -EOPNOTSUPP;
393         else
394                 ret = access_ok(VERIFY_READ, ptr, length) ? 0 : -EFAULT;
395
396         if (ret)
397                 return ret;
398
399         ops.ooblen = length;
400         ops.ooboffs = start & (mtd->oobsize - 1);
401         ops.datbuf = NULL;
402         ops.mode = MTD_OOB_PLACE;
403
404         if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
405                 return -EINVAL;
406
407         ops.oobbuf = kmalloc(length, GFP_KERNEL);
408         if (!ops.oobbuf)
409                 return -ENOMEM;
410
411         if (copy_from_user(ops.oobbuf, ptr, length)) {
412                 kfree(ops.oobbuf);
413                 return -EFAULT;
414         }
415
416         start &= ~((uint64_t)mtd->oobsize - 1);
417         ret = mtd->write_oob(mtd, start, &ops);
418
419         if (ops.oobretlen > 0xFFFFFFFFU)
420                 ret = -EOVERFLOW;
421         retlen = ops.oobretlen;
422         if (copy_to_user(retp, &retlen, sizeof(length)))
423                 ret = -EFAULT;
424
425         kfree(ops.oobbuf);
426         return ret;
427 }
428
429 static int mtd_do_readoob(struct mtd_info *mtd, uint64_t start,
430         uint32_t length, void __user *ptr, uint32_t __user *retp)
431 {
432         struct mtd_oob_ops ops;
433         int ret = 0;
434
435         if (length > 4096)
436                 return -EINVAL;
437
438         if (!mtd->read_oob)
439                 ret = -EOPNOTSUPP;
440         else
441                 ret = access_ok(VERIFY_WRITE, ptr,
442                                 length) ? 0 : -EFAULT;
443         if (ret)
444                 return ret;
445
446         ops.ooblen = length;
447         ops.ooboffs = start & (mtd->oobsize - 1);
448         ops.datbuf = NULL;
449         ops.mode = MTD_OOB_PLACE;
450
451         if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
452                 return -EINVAL;
453
454         ops.oobbuf = kmalloc(length, GFP_KERNEL);
455         if (!ops.oobbuf)
456                 return -ENOMEM;
457
458         start &= ~((uint64_t)mtd->oobsize - 1);
459         ret = mtd->read_oob(mtd, start, &ops);
460
461         if (put_user(ops.oobretlen, retp))
462                 ret = -EFAULT;
463         else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
464                                             ops.oobretlen))
465                 ret = -EFAULT;
466
467         kfree(ops.oobbuf);
468         return ret;
469 }
470
471 static int mtd_ioctl(struct file *file, u_int cmd, u_long arg)
472 {
473         struct mtd_file_info *mfi = file->private_data;
474         struct mtd_info *mtd = mfi->mtd;
475         void __user *argp = (void __user *)arg;
476         int ret = 0;
477         u_long size;
478         struct mtd_info_user info;
479
480         DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
481
482         size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
483         if (cmd & IOC_IN) {
484                 if (!access_ok(VERIFY_READ, argp, size))
485                         return -EFAULT;
486         }
487         if (cmd & IOC_OUT) {
488                 if (!access_ok(VERIFY_WRITE, argp, size))
489                         return -EFAULT;
490         }
491
492         switch (cmd) {
493         case MEMGETREGIONCOUNT:
494                 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
495                         return -EFAULT;
496                 break;
497
498         case MEMGETREGIONINFO:
499         {
500                 uint32_t ur_idx;
501                 struct mtd_erase_region_info *kr;
502                 struct region_info_user __user *ur = argp;
503
504                 if (get_user(ur_idx, &(ur->regionindex)))
505                         return -EFAULT;
506
507                 kr = &(mtd->eraseregions[ur_idx]);
508
509                 if (put_user(kr->offset, &(ur->offset))
510                     || put_user(kr->erasesize, &(ur->erasesize))
511                     || put_user(kr->numblocks, &(ur->numblocks)))
512                         return -EFAULT;
513
514                 break;
515         }
516
517         case MEMGETINFO:
518                 info.type       = mtd->type;
519                 info.flags      = mtd->flags;
520                 info.size       = mtd->size;
521                 info.erasesize  = mtd->erasesize;
522                 info.writesize  = mtd->writesize;
523                 info.oobsize    = mtd->oobsize;
524                 /* The below fields are obsolete */
525                 info.ecctype    = -1;
526                 info.eccsize    = 0;
527                 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
528                         return -EFAULT;
529                 break;
530
531         case MEMERASE:
532         case MEMERASE64:
533         {
534                 struct erase_info *erase;
535
536                 if(!(file->f_mode & FMODE_WRITE))
537                         return -EPERM;
538
539                 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
540                 if (!erase)
541                         ret = -ENOMEM;
542                 else {
543                         wait_queue_head_t waitq;
544                         DECLARE_WAITQUEUE(wait, current);
545
546                         init_waitqueue_head(&waitq);
547
548                         if (cmd == MEMERASE64) {
549                                 struct erase_info_user64 einfo64;
550
551                                 if (copy_from_user(&einfo64, argp,
552                                             sizeof(struct erase_info_user64))) {
553                                         kfree(erase);
554                                         return -EFAULT;
555                                 }
556                                 erase->addr = einfo64.start;
557                                 erase->len = einfo64.length;
558                         } else {
559                                 struct erase_info_user einfo32;
560
561                                 if (copy_from_user(&einfo32, argp,
562                                             sizeof(struct erase_info_user))) {
563                                         kfree(erase);
564                                         return -EFAULT;
565                                 }
566                                 erase->addr = einfo32.start;
567                                 erase->len = einfo32.length;
568                         }
569                         erase->mtd = mtd;
570                         erase->callback = mtdchar_erase_callback;
571                         erase->priv = (unsigned long)&waitq;
572
573                         /*
574                           FIXME: Allow INTERRUPTIBLE. Which means
575                           not having the wait_queue head on the stack.
576
577                           If the wq_head is on the stack, and we
578                           leave because we got interrupted, then the
579                           wq_head is no longer there when the
580                           callback routine tries to wake us up.
581                         */
582                         ret = mtd->erase(mtd, erase);
583                         if (!ret) {
584                                 set_current_state(TASK_UNINTERRUPTIBLE);
585                                 add_wait_queue(&waitq, &wait);
586                                 if (erase->state != MTD_ERASE_DONE &&
587                                     erase->state != MTD_ERASE_FAILED)
588                                         schedule();
589                                 remove_wait_queue(&waitq, &wait);
590                                 set_current_state(TASK_RUNNING);
591
592                                 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
593                         }
594                         kfree(erase);
595                 }
596                 break;
597         }
598
599         case MEMWRITEOOB:
600         {
601                 struct mtd_oob_buf buf;
602                 struct mtd_oob_buf __user *buf_user = argp;
603
604                 /* NOTE: writes return length to buf_user->length */
605                 if (copy_from_user(&buf, argp, sizeof(buf)))
606                         ret = -EFAULT;
607                 else
608                         ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
609                                 buf.ptr, &buf_user->length);
610                 break;
611         }
612
613         case MEMREADOOB:
614         {
615                 struct mtd_oob_buf buf;
616                 struct mtd_oob_buf __user *buf_user = argp;
617
618                 /* NOTE: writes return length to buf_user->start */
619                 if (copy_from_user(&buf, argp, sizeof(buf)))
620                         ret = -EFAULT;
621                 else
622                         ret = mtd_do_readoob(mtd, buf.start, buf.length,
623                                 buf.ptr, &buf_user->start);
624                 break;
625         }
626
627         case MEMWRITEOOB64:
628         {
629                 struct mtd_oob_buf64 buf;
630                 struct mtd_oob_buf64 __user *buf_user = argp;
631
632                 if (copy_from_user(&buf, argp, sizeof(buf)))
633                         ret = -EFAULT;
634                 else
635                         ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
636                                 (void __user *)(uintptr_t)buf.usr_ptr,
637                                 &buf_user->length);
638                 break;
639         }
640
641         case MEMREADOOB64:
642         {
643                 struct mtd_oob_buf64 buf;
644                 struct mtd_oob_buf64 __user *buf_user = argp;
645
646                 if (copy_from_user(&buf, argp, sizeof(buf)))
647                         ret = -EFAULT;
648                 else
649                         ret = mtd_do_readoob(mtd, buf.start, buf.length,
650                                 (void __user *)(uintptr_t)buf.usr_ptr,
651                                 &buf_user->length);
652                 break;
653         }
654
655         case MEMLOCK:
656         {
657                 struct erase_info_user einfo;
658
659                 if (copy_from_user(&einfo, argp, sizeof(einfo)))
660                         return -EFAULT;
661
662                 if (!mtd->lock)
663                         ret = -EOPNOTSUPP;
664                 else
665                         ret = mtd->lock(mtd, einfo.start, einfo.length);
666                 break;
667         }
668
669         case MEMUNLOCK:
670         {
671                 struct erase_info_user einfo;
672
673                 if (copy_from_user(&einfo, argp, sizeof(einfo)))
674                         return -EFAULT;
675
676                 if (!mtd->unlock)
677                         ret = -EOPNOTSUPP;
678                 else
679                         ret = mtd->unlock(mtd, einfo.start, einfo.length);
680                 break;
681         }
682
683         /* Legacy interface */
684         case MEMGETOOBSEL:
685         {
686                 struct nand_oobinfo oi;
687
688                 if (!mtd->ecclayout)
689                         return -EOPNOTSUPP;
690                 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
691                         return -EINVAL;
692
693                 oi.useecc = MTD_NANDECC_AUTOPLACE;
694                 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
695                 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
696                        sizeof(oi.oobfree));
697                 oi.eccbytes = mtd->ecclayout->eccbytes;
698
699                 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
700                         return -EFAULT;
701                 break;
702         }
703
704         case MEMGETBADBLOCK:
705         {
706                 loff_t offs;
707
708                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
709                         return -EFAULT;
710                 if (!mtd->block_isbad)
711                         ret = -EOPNOTSUPP;
712                 else
713                         return mtd->block_isbad(mtd, offs);
714                 break;
715         }
716
717         case MEMSETBADBLOCK:
718         {
719                 loff_t offs;
720
721                 if (copy_from_user(&offs, argp, sizeof(loff_t)))
722                         return -EFAULT;
723                 if (!mtd->block_markbad)
724                         ret = -EOPNOTSUPP;
725                 else
726                         return mtd->block_markbad(mtd, offs);
727                 break;
728         }
729
730 #ifdef CONFIG_HAVE_MTD_OTP
731         case OTPSELECT:
732         {
733                 int mode;
734                 if (copy_from_user(&mode, argp, sizeof(int)))
735                         return -EFAULT;
736
737                 mfi->mode = MTD_MODE_NORMAL;
738
739                 ret = otp_select_filemode(mfi, mode);
740
741                 file->f_pos = 0;
742                 break;
743         }
744
745         case OTPGETREGIONCOUNT:
746         case OTPGETREGIONINFO:
747         {
748                 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
749                 if (!buf)
750                         return -ENOMEM;
751                 ret = -EOPNOTSUPP;
752                 switch (mfi->mode) {
753                 case MTD_MODE_OTP_FACTORY:
754                         if (mtd->get_fact_prot_info)
755                                 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
756                         break;
757                 case MTD_MODE_OTP_USER:
758                         if (mtd->get_user_prot_info)
759                                 ret = mtd->get_user_prot_info(mtd, buf, 4096);
760                         break;
761                 default:
762                         break;
763                 }
764                 if (ret >= 0) {
765                         if (cmd == OTPGETREGIONCOUNT) {
766                                 int nbr = ret / sizeof(struct otp_info);
767                                 ret = copy_to_user(argp, &nbr, sizeof(int));
768                         } else
769                                 ret = copy_to_user(argp, buf, ret);
770                         if (ret)
771                                 ret = -EFAULT;
772                 }
773                 kfree(buf);
774                 break;
775         }
776
777         case OTPLOCK:
778         {
779                 struct otp_info oinfo;
780
781                 if (mfi->mode != MTD_MODE_OTP_USER)
782                         return -EINVAL;
783                 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
784                         return -EFAULT;
785                 if (!mtd->lock_user_prot_reg)
786                         return -EOPNOTSUPP;
787                 ret = mtd->lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
788                 break;
789         }
790 #endif
791
792         case ECCGETLAYOUT:
793         {
794                 if (!mtd->ecclayout)
795                         return -EOPNOTSUPP;
796
797                 if (copy_to_user(argp, mtd->ecclayout,
798                                  sizeof(struct nand_ecclayout)))
799                         return -EFAULT;
800                 break;
801         }
802
803         case ECCGETSTATS:
804         {
805                 if (copy_to_user(argp, &mtd->ecc_stats,
806                                  sizeof(struct mtd_ecc_stats)))
807                         return -EFAULT;
808                 break;
809         }
810
811         case MTDFILEMODE:
812         {
813                 mfi->mode = 0;
814
815                 switch(arg) {
816                 case MTD_MODE_OTP_FACTORY:
817                 case MTD_MODE_OTP_USER:
818                         ret = otp_select_filemode(mfi, arg);
819                         break;
820
821                 case MTD_MODE_RAW:
822                         if (!mtd->read_oob || !mtd->write_oob)
823                                 return -EOPNOTSUPP;
824                         mfi->mode = arg;
825
826                 case MTD_MODE_NORMAL:
827                         break;
828                 default:
829                         ret = -EINVAL;
830                 }
831                 file->f_pos = 0;
832                 break;
833         }
834
835         default:
836                 ret = -ENOTTY;
837         }
838
839         return ret;
840 } /* memory_ioctl */
841
842 static long mtd_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
843 {
844         int ret;
845
846         lock_kernel();
847         ret = mtd_ioctl(file, cmd, arg);
848         unlock_kernel();
849
850         return ret;
851 }
852
853 #ifdef CONFIG_COMPAT
854
855 struct mtd_oob_buf32 {
856         u_int32_t start;
857         u_int32_t length;
858         compat_caddr_t ptr;     /* unsigned char* */
859 };
860
861 #define MEMWRITEOOB32           _IOWR('M', 3, struct mtd_oob_buf32)
862 #define MEMREADOOB32            _IOWR('M', 4, struct mtd_oob_buf32)
863
864 static long mtd_compat_ioctl(struct file *file, unsigned int cmd,
865         unsigned long arg)
866 {
867         struct mtd_file_info *mfi = file->private_data;
868         struct mtd_info *mtd = mfi->mtd;
869         void __user *argp = compat_ptr(arg);
870         int ret = 0;
871
872         lock_kernel();
873
874         switch (cmd) {
875         case MEMWRITEOOB32:
876         {
877                 struct mtd_oob_buf32 buf;
878                 struct mtd_oob_buf32 __user *buf_user = argp;
879
880                 if (copy_from_user(&buf, argp, sizeof(buf)))
881                         ret = -EFAULT;
882                 else
883                         ret = mtd_do_writeoob(file, mtd, buf.start,
884                                 buf.length, compat_ptr(buf.ptr),
885                                 &buf_user->length);
886                 break;
887         }
888
889         case MEMREADOOB32:
890         {
891                 struct mtd_oob_buf32 buf;
892                 struct mtd_oob_buf32 __user *buf_user = argp;
893
894                 /* NOTE: writes return length to buf->start */
895                 if (copy_from_user(&buf, argp, sizeof(buf)))
896                         ret = -EFAULT;
897                 else
898                         ret = mtd_do_readoob(mtd, buf.start,
899                                 buf.length, compat_ptr(buf.ptr),
900                                 &buf_user->start);
901                 break;
902         }
903         default:
904                 ret = mtd_ioctl(file, cmd, (unsigned long)argp);
905         }
906
907         unlock_kernel();
908
909         return ret;
910 }
911
912 #endif /* CONFIG_COMPAT */
913
914 /*
915  * try to determine where a shared mapping can be made
916  * - only supported for NOMMU at the moment (MMU can't doesn't copy private
917  *   mappings)
918  */
919 #ifndef CONFIG_MMU
920 static unsigned long mtd_get_unmapped_area(struct file *file,
921                                            unsigned long addr,
922                                            unsigned long len,
923                                            unsigned long pgoff,
924                                            unsigned long flags)
925 {
926         struct mtd_file_info *mfi = file->private_data;
927         struct mtd_info *mtd = mfi->mtd;
928
929         if (mtd->get_unmapped_area) {
930                 unsigned long offset;
931
932                 if (addr != 0)
933                         return (unsigned long) -EINVAL;
934
935                 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
936                         return (unsigned long) -EINVAL;
937
938                 offset = pgoff << PAGE_SHIFT;
939                 if (offset > mtd->size - len)
940                         return (unsigned long) -EINVAL;
941
942                 return mtd->get_unmapped_area(mtd, len, offset, flags);
943         }
944
945         /* can't map directly */
946         return (unsigned long) -ENOSYS;
947 }
948 #endif
949
950 /*
951  * set up a mapping for shared memory segments
952  */
953 static int mtd_mmap(struct file *file, struct vm_area_struct *vma)
954 {
955 #ifdef CONFIG_MMU
956         struct mtd_file_info *mfi = file->private_data;
957         struct mtd_info *mtd = mfi->mtd;
958
959         if (mtd->type == MTD_RAM || mtd->type == MTD_ROM)
960                 return 0;
961         return -ENOSYS;
962 #else
963         return vma->vm_flags & VM_SHARED ? 0 : -ENOSYS;
964 #endif
965 }
966
967 static const struct file_operations mtd_fops = {
968         .owner          = THIS_MODULE,
969         .llseek         = mtd_lseek,
970         .read           = mtd_read,
971         .write          = mtd_write,
972         .unlocked_ioctl = mtd_unlocked_ioctl,
973 #ifdef CONFIG_COMPAT
974         .compat_ioctl   = mtd_compat_ioctl,
975 #endif
976         .open           = mtd_open,
977         .release        = mtd_close,
978         .mmap           = mtd_mmap,
979 #ifndef CONFIG_MMU
980         .get_unmapped_area = mtd_get_unmapped_area,
981 #endif
982 };
983
984 static int mtd_inodefs_get_sb(struct file_system_type *fs_type, int flags,
985                                const char *dev_name, void *data,
986                                struct vfsmount *mnt)
987 {
988         return get_sb_pseudo(fs_type, "mtd_inode:", NULL, MTD_INODE_FS_MAGIC,
989                              mnt);
990 }
991
992 static struct file_system_type mtd_inodefs_type = {
993        .name = "mtd_inodefs",
994        .get_sb = mtd_inodefs_get_sb,
995        .kill_sb = kill_anon_super,
996 };
997
998 static void mtdchar_notify_add(struct mtd_info *mtd)
999 {
1000 }
1001
1002 static void mtdchar_notify_remove(struct mtd_info *mtd)
1003 {
1004         struct inode *mtd_ino = ilookup(mtd_inode_mnt->mnt_sb, mtd->index);
1005
1006         if (mtd_ino) {
1007                 /* Destroy the inode if it exists */
1008                 mtd_ino->i_nlink = 0;
1009                 iput(mtd_ino);
1010         }
1011 }
1012
1013 static struct mtd_notifier mtdchar_notifier = {
1014         .add = mtdchar_notify_add,
1015         .remove = mtdchar_notify_remove,
1016 };
1017
1018 static int __init init_mtdchar(void)
1019 {
1020         int ret;
1021
1022         ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1023                                    "mtd", &mtd_fops);
1024         if (ret < 0) {
1025                 pr_notice("Can't allocate major number %d for "
1026                                 "Memory Technology Devices.\n", MTD_CHAR_MAJOR);
1027                 return ret;
1028         }
1029
1030         ret = register_filesystem(&mtd_inodefs_type);
1031         if (ret) {
1032                 pr_notice("Can't register mtd_inodefs filesystem: %d\n", ret);
1033                 goto err_unregister_chdev;
1034         }
1035
1036         mtd_inode_mnt = kern_mount(&mtd_inodefs_type);
1037         if (IS_ERR(mtd_inode_mnt)) {
1038                 ret = PTR_ERR(mtd_inode_mnt);
1039                 pr_notice("Error mounting mtd_inodefs filesystem: %d\n", ret);
1040                 goto err_unregister_filesystem;
1041         }
1042         register_mtd_user(&mtdchar_notifier);
1043
1044         return ret;
1045
1046 err_unregister_filesystem:
1047         unregister_filesystem(&mtd_inodefs_type);
1048 err_unregister_chdev:
1049         __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1050         return ret;
1051 }
1052
1053 static void __exit cleanup_mtdchar(void)
1054 {
1055         unregister_mtd_user(&mtdchar_notifier);
1056         mntput(mtd_inode_mnt);
1057         unregister_filesystem(&mtd_inodefs_type);
1058         __unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1059 }
1060
1061 module_init(init_mtdchar);
1062 module_exit(cleanup_mtdchar);
1063
1064 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
1065
1066 MODULE_LICENSE("GPL");
1067 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1068 MODULE_DESCRIPTION("Direct character-device access to MTD devices");
1069 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);