First Support on Ginger and OMAP TI
[linux-ginger.git] / drivers / mtd / mtdchar.c
blob5b081cb84351340dd6164fe448703f93c6dfca47
1 /*
2 * Character-device access to raw MTD devices.
4 */
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>
19 #include <linux/mtd/mtd.h>
20 #include <linux/mtd/compatmac.h>
22 #include <asm/uaccess.h>
26 * Data structure to hold the pointer to the mtd device as well
27 * as mode information ofr various use cases.
29 struct mtd_file_info {
30 struct mtd_info *mtd;
31 enum mtd_file_modes mode;
34 static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
36 struct mtd_file_info *mfi = file->private_data;
37 struct mtd_info *mtd = mfi->mtd;
39 switch (orig) {
40 case SEEK_SET:
41 break;
42 case SEEK_CUR:
43 offset += file->f_pos;
44 break;
45 case SEEK_END:
46 offset += mtd->size;
47 break;
48 default:
49 return -EINVAL;
52 if (offset >= 0 && offset <= mtd->size)
53 return file->f_pos = offset;
55 return -EINVAL;
60 static int mtd_open(struct inode *inode, struct file *file)
62 int minor = iminor(inode);
63 int devnum = minor >> 1;
64 int ret = 0;
65 struct mtd_info *mtd;
66 struct mtd_file_info *mfi;
68 DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
70 if (devnum >= MAX_MTD_DEVICES)
71 return -ENODEV;
73 /* You can't open the RO devices RW */
74 if ((file->f_mode & FMODE_WRITE) && (minor & 1))
75 return -EACCES;
77 lock_kernel();
78 mtd = get_mtd_device(NULL, devnum);
80 if (IS_ERR(mtd)) {
81 ret = PTR_ERR(mtd);
82 goto out;
85 if (mtd->type == MTD_ABSENT) {
86 put_mtd_device(mtd);
87 ret = -ENODEV;
88 goto out;
91 if (mtd->backing_dev_info)
92 file->f_mapping->backing_dev_info = mtd->backing_dev_info;
94 /* You can't open it RW if it's not a writeable device */
95 if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
96 put_mtd_device(mtd);
97 ret = -EACCES;
98 goto out;
101 mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
102 if (!mfi) {
103 put_mtd_device(mtd);
104 ret = -ENOMEM;
105 goto out;
107 mfi->mtd = mtd;
108 file->private_data = mfi;
110 out:
111 unlock_kernel();
112 return ret;
113 } /* mtd_open */
115 /*====================================================================*/
117 static int mtd_close(struct inode *inode, struct file *file)
119 struct mtd_file_info *mfi = file->private_data;
120 struct mtd_info *mtd = mfi->mtd;
122 DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
124 /* Only sync if opened RW */
125 if ((file->f_mode & FMODE_WRITE) && mtd->sync)
126 mtd->sync(mtd);
128 put_mtd_device(mtd);
129 file->private_data = NULL;
130 kfree(mfi);
132 return 0;
133 } /* mtd_close */
135 /* FIXME: This _really_ needs to die. In 2.5, we should lock the
136 userspace buffer down and use it directly with readv/writev.
138 #define MAX_KMALLOC_SIZE 0x20000
140 static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
142 struct mtd_file_info *mfi = file->private_data;
143 struct mtd_info *mtd = mfi->mtd;
144 size_t retlen=0;
145 size_t total_retlen=0;
146 int ret=0;
147 int len;
148 char *kbuf;
150 DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
152 if (*ppos + count > mtd->size)
153 count = mtd->size - *ppos;
155 if (!count)
156 return 0;
158 /* FIXME: Use kiovec in 2.5 to lock down the user's buffers
159 and pass them directly to the MTD functions */
161 if (count > MAX_KMALLOC_SIZE)
162 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
163 else
164 kbuf=kmalloc(count, GFP_KERNEL);
166 if (!kbuf)
167 return -ENOMEM;
169 while (count) {
171 if (count > MAX_KMALLOC_SIZE)
172 len = MAX_KMALLOC_SIZE;
173 else
174 len = count;
176 switch (mfi->mode) {
177 case MTD_MODE_OTP_FACTORY:
178 ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
179 break;
180 case MTD_MODE_OTP_USER:
181 ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
182 break;
183 case MTD_MODE_RAW:
185 struct mtd_oob_ops ops;
187 ops.mode = MTD_OOB_RAW;
188 ops.datbuf = kbuf;
189 ops.oobbuf = NULL;
190 ops.len = len;
192 ret = mtd->read_oob(mtd, *ppos, &ops);
193 retlen = ops.retlen;
194 break;
196 default:
197 ret = mtd->read(mtd, *ppos, len, &retlen, kbuf);
199 /* Nand returns -EBADMSG on ecc errors, but it returns
200 * the data. For our userspace tools it is important
201 * to dump areas with ecc errors !
202 * For kernel internal usage it also might return -EUCLEAN
203 * to signal the caller that a bitflip has occured and has
204 * been corrected by the ECC algorithm.
205 * Userspace software which accesses NAND this way
206 * must be aware of the fact that it deals with NAND
208 if (!ret || (ret == -EUCLEAN) || (ret == -EBADMSG)) {
209 *ppos += retlen;
210 if (copy_to_user(buf, kbuf, retlen)) {
211 kfree(kbuf);
212 return -EFAULT;
214 else
215 total_retlen += retlen;
217 count -= retlen;
218 buf += retlen;
219 if (retlen == 0)
220 count = 0;
222 else {
223 kfree(kbuf);
224 return ret;
229 kfree(kbuf);
230 return total_retlen;
231 } /* mtd_read */
233 static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
235 struct mtd_file_info *mfi = file->private_data;
236 struct mtd_info *mtd = mfi->mtd;
237 char *kbuf;
238 size_t retlen;
239 size_t total_retlen=0;
240 int ret=0;
241 int len;
243 DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
245 if (*ppos == mtd->size)
246 return -ENOSPC;
248 if (*ppos + count > mtd->size)
249 count = mtd->size - *ppos;
251 if (!count)
252 return 0;
254 if (count > MAX_KMALLOC_SIZE)
255 kbuf=kmalloc(MAX_KMALLOC_SIZE, GFP_KERNEL);
256 else
257 kbuf=kmalloc(count, GFP_KERNEL);
259 if (!kbuf)
260 return -ENOMEM;
262 while (count) {
264 if (count > MAX_KMALLOC_SIZE)
265 len = MAX_KMALLOC_SIZE;
266 else
267 len = count;
269 if (copy_from_user(kbuf, buf, len)) {
270 kfree(kbuf);
271 return -EFAULT;
274 switch (mfi->mode) {
275 case MTD_MODE_OTP_FACTORY:
276 ret = -EROFS;
277 break;
278 case MTD_MODE_OTP_USER:
279 if (!mtd->write_user_prot_reg) {
280 ret = -EOPNOTSUPP;
281 break;
283 ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
284 break;
286 case MTD_MODE_RAW:
288 struct mtd_oob_ops ops;
290 ops.mode = MTD_OOB_RAW;
291 ops.datbuf = kbuf;
292 ops.oobbuf = NULL;
293 ops.len = len;
295 ret = mtd->write_oob(mtd, *ppos, &ops);
296 retlen = ops.retlen;
297 break;
300 default:
301 ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
303 if (!ret) {
304 *ppos += retlen;
305 total_retlen += retlen;
306 count -= retlen;
307 buf += retlen;
309 else {
310 kfree(kbuf);
311 return ret;
315 kfree(kbuf);
316 return total_retlen;
317 } /* mtd_write */
319 /*======================================================================
321 IOCTL calls for getting device parameters.
323 ======================================================================*/
324 static void mtdchar_erase_callback (struct erase_info *instr)
326 wake_up((wait_queue_head_t *)instr->priv);
329 #ifdef CONFIG_HAVE_MTD_OTP
330 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
332 struct mtd_info *mtd = mfi->mtd;
333 int ret = 0;
335 switch (mode) {
336 case MTD_OTP_FACTORY:
337 if (!mtd->read_fact_prot_reg)
338 ret = -EOPNOTSUPP;
339 else
340 mfi->mode = MTD_MODE_OTP_FACTORY;
341 break;
342 case MTD_OTP_USER:
343 if (!mtd->read_fact_prot_reg)
344 ret = -EOPNOTSUPP;
345 else
346 mfi->mode = MTD_MODE_OTP_USER;
347 break;
348 default:
349 ret = -EINVAL;
350 case MTD_OTP_OFF:
351 break;
353 return ret;
355 #else
356 # define otp_select_filemode(f,m) -EOPNOTSUPP
357 #endif
359 static int mtd_do_writeoob(struct file *file, struct mtd_info *mtd,
360 uint64_t start, uint32_t length, void __user *ptr,
361 uint32_t __user *retp)
363 struct mtd_oob_ops ops;
364 uint32_t retlen;
365 int ret = 0;
367 if (!(file->f_mode & FMODE_WRITE))
368 return -EPERM;
370 if (length > 4096)
371 return -EINVAL;
373 if (!mtd->write_oob)
374 ret = -EOPNOTSUPP;
375 else
376 ret = access_ok(VERIFY_READ, ptr, length) ? 0 : EFAULT;
378 if (ret)
379 return ret;
381 ops.ooblen = length;
382 ops.ooboffs = start & (mtd->oobsize - 1);
383 ops.datbuf = NULL;
384 ops.mode = MTD_OOB_PLACE;
386 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
387 return -EINVAL;
389 ops.oobbuf = kmalloc(length, GFP_KERNEL);
390 if (!ops.oobbuf)
391 return -ENOMEM;
393 if (copy_from_user(ops.oobbuf, ptr, length)) {
394 kfree(ops.oobbuf);
395 return -EFAULT;
398 start &= ~((uint64_t)mtd->oobsize - 1);
399 ret = mtd->write_oob(mtd, start, &ops);
401 if (ops.oobretlen > 0xFFFFFFFFU)
402 ret = -EOVERFLOW;
403 retlen = ops.oobretlen;
404 if (copy_to_user(retp, &retlen, sizeof(length)))
405 ret = -EFAULT;
407 kfree(ops.oobbuf);
408 return ret;
411 static int mtd_do_readoob(struct mtd_info *mtd, uint64_t start,
412 uint32_t length, void __user *ptr, uint32_t __user *retp)
414 struct mtd_oob_ops ops;
415 int ret = 0;
417 if (length > 4096)
418 return -EINVAL;
420 if (!mtd->read_oob)
421 ret = -EOPNOTSUPP;
422 else
423 ret = access_ok(VERIFY_WRITE, ptr,
424 length) ? 0 : -EFAULT;
425 if (ret)
426 return ret;
428 ops.ooblen = length;
429 ops.ooboffs = start & (mtd->oobsize - 1);
430 ops.datbuf = NULL;
431 ops.mode = MTD_OOB_PLACE;
433 if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
434 return -EINVAL;
436 ops.oobbuf = kmalloc(length, GFP_KERNEL);
437 if (!ops.oobbuf)
438 return -ENOMEM;
440 start &= ~((uint64_t)mtd->oobsize - 1);
441 ret = mtd->read_oob(mtd, start, &ops);
443 if (put_user(ops.oobretlen, retp))
444 ret = -EFAULT;
445 else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
446 ops.oobretlen))
447 ret = -EFAULT;
449 kfree(ops.oobbuf);
450 return ret;
453 static int mtd_ioctl(struct inode *inode, struct file *file,
454 u_int cmd, u_long arg)
456 struct mtd_file_info *mfi = file->private_data;
457 struct mtd_info *mtd = mfi->mtd;
458 void __user *argp = (void __user *)arg;
459 int ret = 0;
460 u_long size;
461 struct mtd_info_user info;
463 DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
465 size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
466 if (cmd & IOC_IN) {
467 if (!access_ok(VERIFY_READ, argp, size))
468 return -EFAULT;
470 if (cmd & IOC_OUT) {
471 if (!access_ok(VERIFY_WRITE, argp, size))
472 return -EFAULT;
475 switch (cmd) {
476 case MEMGETREGIONCOUNT:
477 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
478 return -EFAULT;
479 break;
481 case MEMGETREGIONINFO:
483 uint32_t ur_idx;
484 struct mtd_erase_region_info *kr;
485 struct region_info_user *ur = (struct region_info_user *) argp;
487 if (get_user(ur_idx, &(ur->regionindex)))
488 return -EFAULT;
490 kr = &(mtd->eraseregions[ur_idx]);
492 if (put_user(kr->offset, &(ur->offset))
493 || put_user(kr->erasesize, &(ur->erasesize))
494 || put_user(kr->numblocks, &(ur->numblocks)))
495 return -EFAULT;
497 break;
500 case MEMGETINFO:
501 info.type = mtd->type;
502 info.flags = mtd->flags;
503 info.size = mtd->size;
504 info.erasesize = mtd->erasesize;
505 info.writesize = mtd->writesize;
506 info.oobsize = mtd->oobsize;
507 /* The below fields are obsolete */
508 info.ecctype = -1;
509 info.eccsize = 0;
510 if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
511 return -EFAULT;
512 break;
514 case MEMERASE:
515 case MEMERASE64:
517 struct erase_info *erase;
519 if(!(file->f_mode & FMODE_WRITE))
520 return -EPERM;
522 erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
523 if (!erase)
524 ret = -ENOMEM;
525 else {
526 wait_queue_head_t waitq;
527 DECLARE_WAITQUEUE(wait, current);
529 init_waitqueue_head(&waitq);
531 if (cmd == MEMERASE64) {
532 struct erase_info_user64 einfo64;
534 if (copy_from_user(&einfo64, argp,
535 sizeof(struct erase_info_user64))) {
536 kfree(erase);
537 return -EFAULT;
539 erase->addr = einfo64.start;
540 erase->len = einfo64.length;
541 } else {
542 struct erase_info_user einfo32;
544 if (copy_from_user(&einfo32, argp,
545 sizeof(struct erase_info_user))) {
546 kfree(erase);
547 return -EFAULT;
549 erase->addr = einfo32.start;
550 erase->len = einfo32.length;
552 erase->mtd = mtd;
553 erase->callback = mtdchar_erase_callback;
554 erase->priv = (unsigned long)&waitq;
557 FIXME: Allow INTERRUPTIBLE. Which means
558 not having the wait_queue head on the stack.
560 If the wq_head is on the stack, and we
561 leave because we got interrupted, then the
562 wq_head is no longer there when the
563 callback routine tries to wake us up.
565 ret = mtd->erase(mtd, erase);
566 if (!ret) {
567 set_current_state(TASK_UNINTERRUPTIBLE);
568 add_wait_queue(&waitq, &wait);
569 if (erase->state != MTD_ERASE_DONE &&
570 erase->state != MTD_ERASE_FAILED)
571 schedule();
572 remove_wait_queue(&waitq, &wait);
573 set_current_state(TASK_RUNNING);
575 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
577 kfree(erase);
579 break;
582 case MEMWRITEOOB:
584 struct mtd_oob_buf buf;
585 struct mtd_oob_buf __user *buf_user = argp;
587 /* NOTE: writes return length to buf_user->length */
588 if (copy_from_user(&buf, argp, sizeof(buf)))
589 ret = -EFAULT;
590 else
591 ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
592 buf.ptr, &buf_user->length);
593 break;
596 case MEMREADOOB:
598 struct mtd_oob_buf buf;
599 struct mtd_oob_buf __user *buf_user = argp;
601 /* NOTE: writes return length to buf_user->start */
602 if (copy_from_user(&buf, argp, sizeof(buf)))
603 ret = -EFAULT;
604 else
605 ret = mtd_do_readoob(mtd, buf.start, buf.length,
606 buf.ptr, &buf_user->start);
607 break;
610 case MEMWRITEOOB64:
612 struct mtd_oob_buf64 buf;
613 struct mtd_oob_buf64 __user *buf_user = argp;
615 if (copy_from_user(&buf, argp, sizeof(buf)))
616 ret = -EFAULT;
617 else
618 ret = mtd_do_writeoob(file, mtd, buf.start, buf.length,
619 (void __user *)(uintptr_t)buf.usr_ptr,
620 &buf_user->length);
621 break;
624 case MEMREADOOB64:
626 struct mtd_oob_buf64 buf;
627 struct mtd_oob_buf64 __user *buf_user = argp;
629 if (copy_from_user(&buf, argp, sizeof(buf)))
630 ret = -EFAULT;
631 else
632 ret = mtd_do_readoob(mtd, buf.start, buf.length,
633 (void __user *)(uintptr_t)buf.usr_ptr,
634 &buf_user->length);
635 break;
638 case MEMLOCK:
640 struct erase_info_user einfo;
642 if (copy_from_user(&einfo, argp, sizeof(einfo)))
643 return -EFAULT;
645 if (!mtd->lock)
646 ret = -EOPNOTSUPP;
647 else
648 ret = mtd->lock(mtd, einfo.start, einfo.length);
649 break;
652 case MEMUNLOCK:
654 struct erase_info_user einfo;
656 if (copy_from_user(&einfo, argp, sizeof(einfo)))
657 return -EFAULT;
659 if (!mtd->unlock)
660 ret = -EOPNOTSUPP;
661 else
662 ret = mtd->unlock(mtd, einfo.start, einfo.length);
663 break;
666 /* Legacy interface */
667 case MEMGETOOBSEL:
669 struct nand_oobinfo oi;
671 if (!mtd->ecclayout)
672 return -EOPNOTSUPP;
673 if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
674 return -EINVAL;
676 oi.useecc = MTD_NANDECC_AUTOPLACE;
677 memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
678 memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
679 sizeof(oi.oobfree));
680 oi.eccbytes = mtd->ecclayout->eccbytes;
682 if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
683 return -EFAULT;
684 break;
687 case MEMGETBADBLOCK:
689 loff_t offs;
691 if (copy_from_user(&offs, argp, sizeof(loff_t)))
692 return -EFAULT;
693 if (!mtd->block_isbad)
694 ret = -EOPNOTSUPP;
695 else
696 return mtd->block_isbad(mtd, offs);
697 break;
700 case MEMSETBADBLOCK:
702 loff_t offs;
704 if (copy_from_user(&offs, argp, sizeof(loff_t)))
705 return -EFAULT;
706 if (!mtd->block_markbad)
707 ret = -EOPNOTSUPP;
708 else
709 return mtd->block_markbad(mtd, offs);
710 break;
713 #ifdef CONFIG_HAVE_MTD_OTP
714 case OTPSELECT:
716 int mode;
717 if (copy_from_user(&mode, argp, sizeof(int)))
718 return -EFAULT;
720 mfi->mode = MTD_MODE_NORMAL;
722 ret = otp_select_filemode(mfi, mode);
724 file->f_pos = 0;
725 break;
728 case OTPGETREGIONCOUNT:
729 case OTPGETREGIONINFO:
731 struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
732 if (!buf)
733 return -ENOMEM;
734 ret = -EOPNOTSUPP;
735 switch (mfi->mode) {
736 case MTD_MODE_OTP_FACTORY:
737 if (mtd->get_fact_prot_info)
738 ret = mtd->get_fact_prot_info(mtd, buf, 4096);
739 break;
740 case MTD_MODE_OTP_USER:
741 if (mtd->get_user_prot_info)
742 ret = mtd->get_user_prot_info(mtd, buf, 4096);
743 break;
744 default:
745 break;
747 if (ret >= 0) {
748 if (cmd == OTPGETREGIONCOUNT) {
749 int nbr = ret / sizeof(struct otp_info);
750 ret = copy_to_user(argp, &nbr, sizeof(int));
751 } else
752 ret = copy_to_user(argp, buf, ret);
753 if (ret)
754 ret = -EFAULT;
756 kfree(buf);
757 break;
760 case OTPLOCK:
762 struct otp_info oinfo;
764 if (mfi->mode != MTD_MODE_OTP_USER)
765 return -EINVAL;
766 if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
767 return -EFAULT;
768 if (!mtd->lock_user_prot_reg)
769 return -EOPNOTSUPP;
770 ret = mtd->lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
771 break;
773 #endif
775 case ECCGETLAYOUT:
777 if (!mtd->ecclayout)
778 return -EOPNOTSUPP;
780 if (copy_to_user(argp, mtd->ecclayout,
781 sizeof(struct nand_ecclayout)))
782 return -EFAULT;
783 break;
786 case ECCGETSTATS:
788 if (copy_to_user(argp, &mtd->ecc_stats,
789 sizeof(struct mtd_ecc_stats)))
790 return -EFAULT;
791 break;
794 case MTDFILEMODE:
796 mfi->mode = 0;
798 switch(arg) {
799 case MTD_MODE_OTP_FACTORY:
800 case MTD_MODE_OTP_USER:
801 ret = otp_select_filemode(mfi, arg);
802 break;
804 case MTD_MODE_RAW:
805 if (!mtd->read_oob || !mtd->write_oob)
806 return -EOPNOTSUPP;
807 mfi->mode = arg;
809 case MTD_MODE_NORMAL:
810 break;
811 default:
812 ret = -EINVAL;
814 file->f_pos = 0;
815 break;
818 default:
819 ret = -ENOTTY;
822 return ret;
823 } /* memory_ioctl */
825 #ifdef CONFIG_COMPAT
827 struct mtd_oob_buf32 {
828 u_int32_t start;
829 u_int32_t length;
830 compat_caddr_t ptr; /* unsigned char* */
833 #define MEMWRITEOOB32 _IOWR('M', 3, struct mtd_oob_buf32)
834 #define MEMREADOOB32 _IOWR('M', 4, struct mtd_oob_buf32)
836 static long mtd_compat_ioctl(struct file *file, unsigned int cmd,
837 unsigned long arg)
839 struct inode *inode = file->f_path.dentry->d_inode;
840 struct mtd_file_info *mfi = file->private_data;
841 struct mtd_info *mtd = mfi->mtd;
842 void __user *argp = compat_ptr(arg);
843 int ret = 0;
845 lock_kernel();
847 switch (cmd) {
848 case MEMWRITEOOB32:
850 struct mtd_oob_buf32 buf;
851 struct mtd_oob_buf32 __user *buf_user = argp;
853 if (copy_from_user(&buf, argp, sizeof(buf)))
854 ret = -EFAULT;
855 else
856 ret = mtd_do_writeoob(file, mtd, buf.start,
857 buf.length, compat_ptr(buf.ptr),
858 &buf_user->length);
859 break;
862 case MEMREADOOB32:
864 struct mtd_oob_buf32 buf;
865 struct mtd_oob_buf32 __user *buf_user = argp;
867 /* NOTE: writes return length to buf->start */
868 if (copy_from_user(&buf, argp, sizeof(buf)))
869 ret = -EFAULT;
870 else
871 ret = mtd_do_readoob(mtd, buf.start,
872 buf.length, compat_ptr(buf.ptr),
873 &buf_user->start);
874 break;
876 default:
877 ret = mtd_ioctl(inode, file, cmd, (unsigned long)argp);
880 unlock_kernel();
882 return ret;
885 #endif /* CONFIG_COMPAT */
888 * try to determine where a shared mapping can be made
889 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
890 * mappings)
892 #ifndef CONFIG_MMU
893 static unsigned long mtd_get_unmapped_area(struct file *file,
894 unsigned long addr,
895 unsigned long len,
896 unsigned long pgoff,
897 unsigned long flags)
899 struct mtd_file_info *mfi = file->private_data;
900 struct mtd_info *mtd = mfi->mtd;
902 if (mtd->get_unmapped_area) {
903 unsigned long offset;
905 if (addr != 0)
906 return (unsigned long) -EINVAL;
908 if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
909 return (unsigned long) -EINVAL;
911 offset = pgoff << PAGE_SHIFT;
912 if (offset > mtd->size - len)
913 return (unsigned long) -EINVAL;
915 return mtd->get_unmapped_area(mtd, len, offset, flags);
918 /* can't map directly */
919 return (unsigned long) -ENOSYS;
921 #endif
924 * set up a mapping for shared memory segments
926 static int mtd_mmap(struct file *file, struct vm_area_struct *vma)
928 #ifdef CONFIG_MMU
929 struct mtd_file_info *mfi = file->private_data;
930 struct mtd_info *mtd = mfi->mtd;
932 if (mtd->type == MTD_RAM || mtd->type == MTD_ROM)
933 return 0;
934 return -ENOSYS;
935 #else
936 return vma->vm_flags & VM_SHARED ? 0 : -ENOSYS;
937 #endif
940 static const struct file_operations mtd_fops = {
941 .owner = THIS_MODULE,
942 .llseek = mtd_lseek,
943 .read = mtd_read,
944 .write = mtd_write,
945 .ioctl = mtd_ioctl,
946 #ifdef CONFIG_COMPAT
947 .compat_ioctl = mtd_compat_ioctl,
948 #endif
949 .open = mtd_open,
950 .release = mtd_close,
951 .mmap = mtd_mmap,
952 #ifndef CONFIG_MMU
953 .get_unmapped_area = mtd_get_unmapped_area,
954 #endif
957 static int __init init_mtdchar(void)
959 int status;
961 status = register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops);
962 if (status < 0) {
963 printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
964 MTD_CHAR_MAJOR);
967 return status;
970 static void __exit cleanup_mtdchar(void)
972 unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
975 module_init(init_mtdchar);
976 module_exit(cleanup_mtdchar);
978 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
980 MODULE_LICENSE("GPL");
981 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
982 MODULE_DESCRIPTION("Direct character-device access to MTD devices");
983 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);