2 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
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.
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.
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
20 #include <linux/device.h>
23 #include <linux/err.h>
24 #include <linux/init.h>
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/slab.h>
28 #include <linux/sched.h>
29 #include <linux/mutex.h>
30 #include <linux/backing-dev.h>
31 #include <linux/compat.h>
32 #include <linux/mount.h>
33 #include <linux/blkpg.h>
34 #include <linux/magic.h>
35 #include <linux/mtd/mtd.h>
36 #include <linux/mtd/partitions.h>
37 #include <linux/mtd/map.h>
39 #include <asm/uaccess.h>
41 static DEFINE_MUTEX(mtd_mutex
);
44 * Data structure to hold the pointer to the mtd device as well
45 * as mode information of various use cases.
47 struct mtd_file_info
{
50 enum mtd_file_modes mode
;
53 static loff_t
mtdchar_lseek(struct file
*file
, loff_t offset
, int orig
)
55 struct mtd_file_info
*mfi
= file
->private_data
;
56 struct mtd_info
*mtd
= mfi
->mtd
;
62 offset
+= file
->f_pos
;
71 if (offset
>= 0 && offset
<= mtd
->size
)
72 return file
->f_pos
= offset
;
78 static struct vfsmount
*mnt
;
79 static struct file_system_type mtd_inodefs_type
;
81 static int mtdchar_open(struct inode
*inode
, struct file
*file
)
83 int minor
= iminor(inode
);
84 int devnum
= minor
>> 1;
87 struct mtd_file_info
*mfi
;
88 struct inode
*mtd_ino
;
90 pr_debug("MTD_open\n");
92 /* You can't open the RO devices RW */
93 if ((file
->f_mode
& FMODE_WRITE
) && (minor
& 1))
96 ret
= simple_pin_fs(&mtd_inodefs_type
, &mnt
, &count
);
100 mutex_lock(&mtd_mutex
);
101 mtd
= get_mtd_device(NULL
, devnum
);
108 if (mtd
->type
== MTD_ABSENT
) {
113 mtd_ino
= iget_locked(mnt
->mnt_sb
, devnum
);
118 if (mtd_ino
->i_state
& I_NEW
) {
119 mtd_ino
->i_private
= mtd
;
120 mtd_ino
->i_mode
= S_IFCHR
;
121 mtd_ino
->i_data
.backing_dev_info
= mtd
->backing_dev_info
;
122 unlock_new_inode(mtd_ino
);
124 file
->f_mapping
= mtd_ino
->i_mapping
;
126 /* You can't open it RW if it's not a writeable device */
127 if ((file
->f_mode
& FMODE_WRITE
) && !(mtd
->flags
& MTD_WRITEABLE
)) {
132 mfi
= kzalloc(sizeof(*mfi
), GFP_KERNEL
);
139 file
->private_data
= mfi
;
140 mutex_unlock(&mtd_mutex
);
148 mutex_unlock(&mtd_mutex
);
149 simple_release_fs(&mnt
, &count
);
153 /*====================================================================*/
155 static int mtdchar_close(struct inode
*inode
, struct file
*file
)
157 struct mtd_file_info
*mfi
= file
->private_data
;
158 struct mtd_info
*mtd
= mfi
->mtd
;
160 pr_debug("MTD_close\n");
162 /* Only sync if opened RW */
163 if ((file
->f_mode
& FMODE_WRITE
))
169 file
->private_data
= NULL
;
171 simple_release_fs(&mnt
, &count
);
174 } /* mtdchar_close */
176 /* Back in June 2001, dwmw2 wrote:
178 * FIXME: This _really_ needs to die. In 2.5, we should lock the
179 * userspace buffer down and use it directly with readv/writev.
181 * The implementation below, using mtd_kmalloc_up_to, mitigates
182 * allocation failures when the system is under low-memory situations
183 * or if memory is highly fragmented at the cost of reducing the
184 * performance of the requested transfer due to a smaller buffer size.
186 * A more complex but more memory-efficient implementation based on
187 * get_user_pages and iovecs to cover extents of those pages is a
188 * longer-term goal, as intimated by dwmw2 above. However, for the
189 * write case, this requires yet more complex head and tail transfer
190 * handling when those head and tail offsets and sizes are such that
191 * alignment requirements are not met in the NAND subdriver.
194 static ssize_t
mtdchar_read(struct file
*file
, char __user
*buf
, size_t count
,
197 struct mtd_file_info
*mfi
= file
->private_data
;
198 struct mtd_info
*mtd
= mfi
->mtd
;
200 size_t total_retlen
=0;
206 pr_debug("MTD_read\n");
208 if (*ppos
+ count
> mtd
->size
)
209 count
= mtd
->size
- *ppos
;
214 kbuf
= mtd_kmalloc_up_to(mtd
, &size
);
219 len
= min_t(size_t, count
, size
);
222 case MTD_FILE_MODE_OTP_FACTORY
:
223 ret
= mtd_read_fact_prot_reg(mtd
, *ppos
, len
,
226 case MTD_FILE_MODE_OTP_USER
:
227 ret
= mtd_read_user_prot_reg(mtd
, *ppos
, len
,
230 case MTD_FILE_MODE_RAW
:
232 struct mtd_oob_ops ops
;
234 ops
.mode
= MTD_OPS_RAW
;
239 ret
= mtd_read_oob(mtd
, *ppos
, &ops
);
244 ret
= mtd_read(mtd
, *ppos
, len
, &retlen
, kbuf
);
246 /* Nand returns -EBADMSG on ECC errors, but it returns
247 * the data. For our userspace tools it is important
248 * to dump areas with ECC errors!
249 * For kernel internal usage it also might return -EUCLEAN
250 * to signal the caller that a bitflip has occurred and has
251 * been corrected by the ECC algorithm.
252 * Userspace software which accesses NAND this way
253 * must be aware of the fact that it deals with NAND
255 if (!ret
|| mtd_is_bitflip_or_eccerr(ret
)) {
257 if (copy_to_user(buf
, kbuf
, retlen
)) {
262 total_retlen
+= retlen
;
280 static ssize_t
mtdchar_write(struct file
*file
, const char __user
*buf
, size_t count
,
283 struct mtd_file_info
*mfi
= file
->private_data
;
284 struct mtd_info
*mtd
= mfi
->mtd
;
288 size_t total_retlen
=0;
292 pr_debug("MTD_write\n");
294 if (*ppos
== mtd
->size
)
297 if (*ppos
+ count
> mtd
->size
)
298 count
= mtd
->size
- *ppos
;
303 kbuf
= mtd_kmalloc_up_to(mtd
, &size
);
308 len
= min_t(size_t, count
, size
);
310 if (copy_from_user(kbuf
, buf
, len
)) {
316 case MTD_FILE_MODE_OTP_FACTORY
:
319 case MTD_FILE_MODE_OTP_USER
:
320 ret
= mtd_write_user_prot_reg(mtd
, *ppos
, len
,
324 case MTD_FILE_MODE_RAW
:
326 struct mtd_oob_ops ops
;
328 ops
.mode
= MTD_OPS_RAW
;
334 ret
= mtd_write_oob(mtd
, *ppos
, &ops
);
340 ret
= mtd_write(mtd
, *ppos
, len
, &retlen
, kbuf
);
344 total_retlen
+= retlen
;
356 } /* mtdchar_write */
358 /*======================================================================
360 IOCTL calls for getting device parameters.
362 ======================================================================*/
363 static void mtdchar_erase_callback (struct erase_info
*instr
)
365 wake_up((wait_queue_head_t
*)instr
->priv
);
368 #ifdef CONFIG_HAVE_MTD_OTP
369 static int otp_select_filemode(struct mtd_file_info
*mfi
, int mode
)
371 struct mtd_info
*mtd
= mfi
->mtd
;
376 * Make a fake call to mtd_read_fact_prot_reg() to check if OTP
377 * operations are supported.
379 if (mtd_read_fact_prot_reg(mtd
, -1, 0, &retlen
, NULL
) == -EOPNOTSUPP
)
383 case MTD_OTP_FACTORY
:
384 mfi
->mode
= MTD_FILE_MODE_OTP_FACTORY
;
387 mfi
->mode
= MTD_FILE_MODE_OTP_USER
;
397 # define otp_select_filemode(f,m) -EOPNOTSUPP
400 static int mtdchar_writeoob(struct file
*file
, struct mtd_info
*mtd
,
401 uint64_t start
, uint32_t length
, void __user
*ptr
,
402 uint32_t __user
*retp
)
404 struct mtd_file_info
*mfi
= file
->private_data
;
405 struct mtd_oob_ops ops
;
409 if (!(file
->f_mode
& FMODE_WRITE
))
415 if (!mtd
->_write_oob
)
418 ret
= access_ok(VERIFY_READ
, ptr
, length
) ? 0 : -EFAULT
;
424 ops
.ooboffs
= start
& (mtd
->writesize
- 1);
426 ops
.mode
= (mfi
->mode
== MTD_FILE_MODE_RAW
) ? MTD_OPS_RAW
:
429 if (ops
.ooboffs
&& ops
.ooblen
> (mtd
->oobsize
- ops
.ooboffs
))
432 ops
.oobbuf
= memdup_user(ptr
, length
);
433 if (IS_ERR(ops
.oobbuf
))
434 return PTR_ERR(ops
.oobbuf
);
436 start
&= ~((uint64_t)mtd
->writesize
- 1);
437 ret
= mtd_write_oob(mtd
, start
, &ops
);
439 if (ops
.oobretlen
> 0xFFFFFFFFU
)
441 retlen
= ops
.oobretlen
;
442 if (copy_to_user(retp
, &retlen
, sizeof(length
)))
449 static int mtdchar_readoob(struct file
*file
, struct mtd_info
*mtd
,
450 uint64_t start
, uint32_t length
, void __user
*ptr
,
451 uint32_t __user
*retp
)
453 struct mtd_file_info
*mfi
= file
->private_data
;
454 struct mtd_oob_ops ops
;
460 if (!access_ok(VERIFY_WRITE
, ptr
, length
))
464 ops
.ooboffs
= start
& (mtd
->writesize
- 1);
466 ops
.mode
= (mfi
->mode
== MTD_FILE_MODE_RAW
) ? MTD_OPS_RAW
:
469 if (ops
.ooboffs
&& ops
.ooblen
> (mtd
->oobsize
- ops
.ooboffs
))
472 ops
.oobbuf
= kmalloc(length
, GFP_KERNEL
);
476 start
&= ~((uint64_t)mtd
->writesize
- 1);
477 ret
= mtd_read_oob(mtd
, start
, &ops
);
479 if (put_user(ops
.oobretlen
, retp
))
481 else if (ops
.oobretlen
&& copy_to_user(ptr
, ops
.oobbuf
,
488 * NAND returns -EBADMSG on ECC errors, but it returns the OOB
489 * data. For our userspace tools it is important to dump areas
491 * For kernel internal usage it also might return -EUCLEAN
492 * to signal the caller that a bitflip has occured and has
493 * been corrected by the ECC algorithm.
495 * Note: currently the standard NAND function, nand_read_oob_std,
496 * does not calculate ECC for the OOB area, so do not rely on
497 * this behavior unless you have replaced it with your own.
499 if (mtd_is_bitflip_or_eccerr(ret
))
506 * Copies (and truncates, if necessary) data from the larger struct,
507 * nand_ecclayout, to the smaller, deprecated layout struct,
508 * nand_ecclayout_user. This is necessary only to support the deprecated
509 * API ioctl ECCGETLAYOUT while allowing all new functionality to use
510 * nand_ecclayout flexibly (i.e. the struct may change size in new
511 * releases without requiring major rewrites).
513 static int shrink_ecclayout(const struct nand_ecclayout
*from
,
514 struct nand_ecclayout_user
*to
)
521 memset(to
, 0, sizeof(*to
));
523 to
->eccbytes
= min((int)from
->eccbytes
, MTD_MAX_ECCPOS_ENTRIES
);
524 for (i
= 0; i
< to
->eccbytes
; i
++)
525 to
->eccpos
[i
] = from
->eccpos
[i
];
527 for (i
= 0; i
< MTD_MAX_OOBFREE_ENTRIES
; i
++) {
528 if (from
->oobfree
[i
].length
== 0 &&
529 from
->oobfree
[i
].offset
== 0)
531 to
->oobavail
+= from
->oobfree
[i
].length
;
532 to
->oobfree
[i
] = from
->oobfree
[i
];
538 static int mtdchar_blkpg_ioctl(struct mtd_info
*mtd
,
539 struct blkpg_ioctl_arg __user
*arg
)
541 struct blkpg_ioctl_arg a
;
542 struct blkpg_partition p
;
544 if (!capable(CAP_SYS_ADMIN
))
547 if (copy_from_user(&a
, arg
, sizeof(struct blkpg_ioctl_arg
)))
550 if (copy_from_user(&p
, a
.data
, sizeof(struct blkpg_partition
)))
554 case BLKPG_ADD_PARTITION
:
556 /* Only master mtd device must be used to add partitions */
557 if (mtd_is_partition(mtd
))
560 return mtd_add_partition(mtd
, p
.devname
, p
.start
, p
.length
);
562 case BLKPG_DEL_PARTITION
:
567 return mtd_del_partition(mtd
, p
.pno
);
574 static int mtdchar_write_ioctl(struct mtd_info
*mtd
,
575 struct mtd_write_req __user
*argp
)
577 struct mtd_write_req req
;
578 struct mtd_oob_ops ops
;
579 void __user
*usr_data
, *usr_oob
;
582 if (copy_from_user(&req
, argp
, sizeof(req
)) ||
583 !access_ok(VERIFY_READ
, req
.usr_data
, req
.len
) ||
584 !access_ok(VERIFY_READ
, req
.usr_oob
, req
.ooblen
))
586 if (!mtd
->_write_oob
)
590 ops
.len
= (size_t)req
.len
;
591 ops
.ooblen
= (size_t)req
.ooblen
;
594 usr_data
= (void __user
*)(uintptr_t)req
.usr_data
;
595 usr_oob
= (void __user
*)(uintptr_t)req
.usr_oob
;
598 ops
.datbuf
= memdup_user(usr_data
, ops
.len
);
599 if (IS_ERR(ops
.datbuf
))
600 return PTR_ERR(ops
.datbuf
);
606 ops
.oobbuf
= memdup_user(usr_oob
, ops
.ooblen
);
607 if (IS_ERR(ops
.oobbuf
)) {
609 return PTR_ERR(ops
.oobbuf
);
615 ret
= mtd_write_oob(mtd
, (loff_t
)req
.start
, &ops
);
623 static int mtdchar_ioctl(struct file
*file
, u_int cmd
, u_long arg
)
625 struct mtd_file_info
*mfi
= file
->private_data
;
626 struct mtd_info
*mtd
= mfi
->mtd
;
627 void __user
*argp
= (void __user
*)arg
;
630 struct mtd_info_user info
;
632 pr_debug("MTD_ioctl\n");
634 size
= (cmd
& IOCSIZE_MASK
) >> IOCSIZE_SHIFT
;
636 if (!access_ok(VERIFY_READ
, argp
, size
))
640 if (!access_ok(VERIFY_WRITE
, argp
, size
))
645 case MEMGETREGIONCOUNT
:
646 if (copy_to_user(argp
, &(mtd
->numeraseregions
), sizeof(int)))
650 case MEMGETREGIONINFO
:
653 struct mtd_erase_region_info
*kr
;
654 struct region_info_user __user
*ur
= argp
;
656 if (get_user(ur_idx
, &(ur
->regionindex
)))
659 if (ur_idx
>= mtd
->numeraseregions
)
662 kr
= &(mtd
->eraseregions
[ur_idx
]);
664 if (put_user(kr
->offset
, &(ur
->offset
))
665 || put_user(kr
->erasesize
, &(ur
->erasesize
))
666 || put_user(kr
->numblocks
, &(ur
->numblocks
)))
673 memset(&info
, 0, sizeof(info
));
674 info
.type
= mtd
->type
;
675 info
.flags
= mtd
->flags
;
676 info
.size
= mtd
->size
;
677 info
.erasesize
= mtd
->erasesize
;
678 info
.writesize
= mtd
->writesize
;
679 info
.oobsize
= mtd
->oobsize
;
680 /* The below field is obsolete */
682 if (copy_to_user(argp
, &info
, sizeof(struct mtd_info_user
)))
689 struct erase_info
*erase
;
691 if(!(file
->f_mode
& FMODE_WRITE
))
694 erase
=kzalloc(sizeof(struct erase_info
),GFP_KERNEL
);
698 wait_queue_head_t waitq
;
699 DECLARE_WAITQUEUE(wait
, current
);
701 init_waitqueue_head(&waitq
);
703 if (cmd
== MEMERASE64
) {
704 struct erase_info_user64 einfo64
;
706 if (copy_from_user(&einfo64
, argp
,
707 sizeof(struct erase_info_user64
))) {
711 erase
->addr
= einfo64
.start
;
712 erase
->len
= einfo64
.length
;
714 struct erase_info_user einfo32
;
716 if (copy_from_user(&einfo32
, argp
,
717 sizeof(struct erase_info_user
))) {
721 erase
->addr
= einfo32
.start
;
722 erase
->len
= einfo32
.length
;
725 erase
->callback
= mtdchar_erase_callback
;
726 erase
->priv
= (unsigned long)&waitq
;
729 FIXME: Allow INTERRUPTIBLE. Which means
730 not having the wait_queue head on the stack.
732 If the wq_head is on the stack, and we
733 leave because we got interrupted, then the
734 wq_head is no longer there when the
735 callback routine tries to wake us up.
737 ret
= mtd_erase(mtd
, erase
);
739 set_current_state(TASK_UNINTERRUPTIBLE
);
740 add_wait_queue(&waitq
, &wait
);
741 if (erase
->state
!= MTD_ERASE_DONE
&&
742 erase
->state
!= MTD_ERASE_FAILED
)
744 remove_wait_queue(&waitq
, &wait
);
745 set_current_state(TASK_RUNNING
);
747 ret
= (erase
->state
== MTD_ERASE_FAILED
)?-EIO
:0;
756 struct mtd_oob_buf buf
;
757 struct mtd_oob_buf __user
*buf_user
= argp
;
759 /* NOTE: writes return length to buf_user->length */
760 if (copy_from_user(&buf
, argp
, sizeof(buf
)))
763 ret
= mtdchar_writeoob(file
, mtd
, buf
.start
, buf
.length
,
764 buf
.ptr
, &buf_user
->length
);
770 struct mtd_oob_buf buf
;
771 struct mtd_oob_buf __user
*buf_user
= argp
;
773 /* NOTE: writes return length to buf_user->start */
774 if (copy_from_user(&buf
, argp
, sizeof(buf
)))
777 ret
= mtdchar_readoob(file
, mtd
, buf
.start
, buf
.length
,
778 buf
.ptr
, &buf_user
->start
);
784 struct mtd_oob_buf64 buf
;
785 struct mtd_oob_buf64 __user
*buf_user
= argp
;
787 if (copy_from_user(&buf
, argp
, sizeof(buf
)))
790 ret
= mtdchar_writeoob(file
, mtd
, buf
.start
, buf
.length
,
791 (void __user
*)(uintptr_t)buf
.usr_ptr
,
798 struct mtd_oob_buf64 buf
;
799 struct mtd_oob_buf64 __user
*buf_user
= argp
;
801 if (copy_from_user(&buf
, argp
, sizeof(buf
)))
804 ret
= mtdchar_readoob(file
, mtd
, buf
.start
, buf
.length
,
805 (void __user
*)(uintptr_t)buf
.usr_ptr
,
812 ret
= mtdchar_write_ioctl(mtd
,
813 (struct mtd_write_req __user
*)arg
);
819 struct erase_info_user einfo
;
821 if (copy_from_user(&einfo
, argp
, sizeof(einfo
)))
824 ret
= mtd_lock(mtd
, einfo
.start
, einfo
.length
);
830 struct erase_info_user einfo
;
832 if (copy_from_user(&einfo
, argp
, sizeof(einfo
)))
835 ret
= mtd_unlock(mtd
, einfo
.start
, einfo
.length
);
841 struct erase_info_user einfo
;
843 if (copy_from_user(&einfo
, argp
, sizeof(einfo
)))
846 ret
= mtd_is_locked(mtd
, einfo
.start
, einfo
.length
);
850 /* Legacy interface */
853 struct nand_oobinfo oi
;
857 if (mtd
->ecclayout
->eccbytes
> ARRAY_SIZE(oi
.eccpos
))
860 oi
.useecc
= MTD_NANDECC_AUTOPLACE
;
861 memcpy(&oi
.eccpos
, mtd
->ecclayout
->eccpos
, sizeof(oi
.eccpos
));
862 memcpy(&oi
.oobfree
, mtd
->ecclayout
->oobfree
,
864 oi
.eccbytes
= mtd
->ecclayout
->eccbytes
;
866 if (copy_to_user(argp
, &oi
, sizeof(struct nand_oobinfo
)))
875 if (copy_from_user(&offs
, argp
, sizeof(loff_t
)))
877 return mtd_block_isbad(mtd
, offs
);
885 if (copy_from_user(&offs
, argp
, sizeof(loff_t
)))
887 return mtd_block_markbad(mtd
, offs
);
891 #ifdef CONFIG_HAVE_MTD_OTP
895 if (copy_from_user(&mode
, argp
, sizeof(int)))
898 mfi
->mode
= MTD_FILE_MODE_NORMAL
;
900 ret
= otp_select_filemode(mfi
, mode
);
906 case OTPGETREGIONCOUNT
:
907 case OTPGETREGIONINFO
:
909 struct otp_info
*buf
= kmalloc(4096, GFP_KERNEL
);
913 case MTD_FILE_MODE_OTP_FACTORY
:
914 ret
= mtd_get_fact_prot_info(mtd
, buf
, 4096);
916 case MTD_FILE_MODE_OTP_USER
:
917 ret
= mtd_get_user_prot_info(mtd
, buf
, 4096);
924 if (cmd
== OTPGETREGIONCOUNT
) {
925 int nbr
= ret
/ sizeof(struct otp_info
);
926 ret
= copy_to_user(argp
, &nbr
, sizeof(int));
928 ret
= copy_to_user(argp
, buf
, ret
);
938 struct otp_info oinfo
;
940 if (mfi
->mode
!= MTD_FILE_MODE_OTP_USER
)
942 if (copy_from_user(&oinfo
, argp
, sizeof(oinfo
)))
944 ret
= mtd_lock_user_prot_reg(mtd
, oinfo
.start
, oinfo
.length
);
949 /* This ioctl is being deprecated - it truncates the ECC layout */
952 struct nand_ecclayout_user
*usrlay
;
957 usrlay
= kmalloc(sizeof(*usrlay
), GFP_KERNEL
);
961 shrink_ecclayout(mtd
->ecclayout
, usrlay
);
963 if (copy_to_user(argp
, usrlay
, sizeof(*usrlay
)))
971 if (copy_to_user(argp
, &mtd
->ecc_stats
,
972 sizeof(struct mtd_ecc_stats
)))
982 case MTD_FILE_MODE_OTP_FACTORY
:
983 case MTD_FILE_MODE_OTP_USER
:
984 ret
= otp_select_filemode(mfi
, arg
);
987 case MTD_FILE_MODE_RAW
:
988 if (!mtd_has_oob(mtd
))
992 case MTD_FILE_MODE_NORMAL
:
1003 ret
= mtdchar_blkpg_ioctl(mtd
,
1004 (struct blkpg_ioctl_arg __user
*)arg
);
1010 /* No reread partition feature. Just return ok */
1020 } /* memory_ioctl */
1022 static long mtdchar_unlocked_ioctl(struct file
*file
, u_int cmd
, u_long arg
)
1026 mutex_lock(&mtd_mutex
);
1027 ret
= mtdchar_ioctl(file
, cmd
, arg
);
1028 mutex_unlock(&mtd_mutex
);
1033 #ifdef CONFIG_COMPAT
1035 struct mtd_oob_buf32
{
1038 compat_caddr_t ptr
; /* unsigned char* */
1041 #define MEMWRITEOOB32 _IOWR('M', 3, struct mtd_oob_buf32)
1042 #define MEMREADOOB32 _IOWR('M', 4, struct mtd_oob_buf32)
1044 static long mtdchar_compat_ioctl(struct file
*file
, unsigned int cmd
,
1047 struct mtd_file_info
*mfi
= file
->private_data
;
1048 struct mtd_info
*mtd
= mfi
->mtd
;
1049 void __user
*argp
= compat_ptr(arg
);
1052 mutex_lock(&mtd_mutex
);
1057 struct mtd_oob_buf32 buf
;
1058 struct mtd_oob_buf32 __user
*buf_user
= argp
;
1060 if (copy_from_user(&buf
, argp
, sizeof(buf
)))
1063 ret
= mtdchar_writeoob(file
, mtd
, buf
.start
,
1064 buf
.length
, compat_ptr(buf
.ptr
),
1071 struct mtd_oob_buf32 buf
;
1072 struct mtd_oob_buf32 __user
*buf_user
= argp
;
1074 /* NOTE: writes return length to buf->start */
1075 if (copy_from_user(&buf
, argp
, sizeof(buf
)))
1078 ret
= mtdchar_readoob(file
, mtd
, buf
.start
,
1079 buf
.length
, compat_ptr(buf
.ptr
),
1084 ret
= mtdchar_ioctl(file
, cmd
, (unsigned long)argp
);
1087 mutex_unlock(&mtd_mutex
);
1092 #endif /* CONFIG_COMPAT */
1095 * try to determine where a shared mapping can be made
1096 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
1100 static unsigned long mtdchar_get_unmapped_area(struct file
*file
,
1103 unsigned long pgoff
,
1104 unsigned long flags
)
1106 struct mtd_file_info
*mfi
= file
->private_data
;
1107 struct mtd_info
*mtd
= mfi
->mtd
;
1108 unsigned long offset
;
1112 return (unsigned long) -EINVAL
;
1114 if (len
> mtd
->size
|| pgoff
>= (mtd
->size
>> PAGE_SHIFT
))
1115 return (unsigned long) -EINVAL
;
1117 offset
= pgoff
<< PAGE_SHIFT
;
1118 if (offset
> mtd
->size
- len
)
1119 return (unsigned long) -EINVAL
;
1121 ret
= mtd_get_unmapped_area(mtd
, len
, offset
, flags
);
1122 return ret
== -EOPNOTSUPP
? -ENOSYS
: ret
;
1126 static inline unsigned long get_vm_size(struct vm_area_struct
*vma
)
1128 return vma
->vm_end
- vma
->vm_start
;
1131 static inline resource_size_t
get_vm_offset(struct vm_area_struct
*vma
)
1133 return (resource_size_t
) vma
->vm_pgoff
<< PAGE_SHIFT
;
1137 * Set a new vm offset.
1139 * Verify that the incoming offset really works as a page offset,
1140 * and that the offset and size fit in a resource_size_t.
1142 static inline int set_vm_offset(struct vm_area_struct
*vma
, resource_size_t off
)
1144 pgoff_t pgoff
= off
>> PAGE_SHIFT
;
1145 if (off
!= (resource_size_t
) pgoff
<< PAGE_SHIFT
)
1147 if (off
+ get_vm_size(vma
) - 1 < off
)
1149 vma
->vm_pgoff
= pgoff
;
1154 * set up a mapping for shared memory segments
1156 static int mtdchar_mmap(struct file
*file
, struct vm_area_struct
*vma
)
1159 struct mtd_file_info
*mfi
= file
->private_data
;
1160 struct mtd_info
*mtd
= mfi
->mtd
;
1161 struct map_info
*map
= mtd
->priv
;
1162 resource_size_t start
, off
;
1163 unsigned long len
, vma_len
;
1165 /* This is broken because it assumes the MTD device is map-based
1166 and that mtd->priv is a valid struct map_info. It should be
1167 replaced with something that uses the mtd_get_unmapped_area()
1168 operation properly. */
1169 if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
1170 off
= get_vm_offset(vma
);
1172 len
= PAGE_ALIGN((start
& ~PAGE_MASK
) + map
->size
);
1174 vma_len
= get_vm_size(vma
);
1176 /* Overflow in off+len? */
1177 if (vma_len
+ off
< off
)
1179 /* Does it fit in the mapping? */
1180 if (vma_len
+ off
> len
)
1184 /* Did that overflow? */
1187 if (set_vm_offset(vma
, off
) < 0)
1189 vma
->vm_flags
|= VM_IO
| VM_DONTEXPAND
| VM_DONTDUMP
;
1191 #ifdef pgprot_noncached
1192 if (file
->f_flags
& O_DSYNC
|| off
>= __pa(high_memory
))
1193 vma
->vm_page_prot
= pgprot_noncached(vma
->vm_page_prot
);
1195 if (io_remap_pfn_range(vma
, vma
->vm_start
, off
>> PAGE_SHIFT
,
1196 vma
->vm_end
- vma
->vm_start
,
1204 return vma
->vm_flags
& VM_SHARED
? 0 : -ENOSYS
;
1208 static const struct file_operations mtd_fops
= {
1209 .owner
= THIS_MODULE
,
1210 .llseek
= mtdchar_lseek
,
1211 .read
= mtdchar_read
,
1212 .write
= mtdchar_write
,
1213 .unlocked_ioctl
= mtdchar_unlocked_ioctl
,
1214 #ifdef CONFIG_COMPAT
1215 .compat_ioctl
= mtdchar_compat_ioctl
,
1217 .open
= mtdchar_open
,
1218 .release
= mtdchar_close
,
1219 .mmap
= mtdchar_mmap
,
1221 .get_unmapped_area
= mtdchar_get_unmapped_area
,
1225 static const struct super_operations mtd_ops
= {
1226 .drop_inode
= generic_delete_inode
,
1227 .statfs
= simple_statfs
,
1230 static struct dentry
*mtd_inodefs_mount(struct file_system_type
*fs_type
,
1231 int flags
, const char *dev_name
, void *data
)
1233 return mount_pseudo(fs_type
, "mtd_inode:", &mtd_ops
, NULL
, MTD_INODE_FS_MAGIC
);
1236 static struct file_system_type mtd_inodefs_type
= {
1237 .name
= "mtd_inodefs",
1238 .mount
= mtd_inodefs_mount
,
1239 .kill_sb
= kill_anon_super
,
1242 static int __init
init_mtdchar(void)
1246 ret
= __register_chrdev(MTD_CHAR_MAJOR
, 0, 1 << MINORBITS
,
1249 pr_notice("Can't allocate major number %d for "
1250 "Memory Technology Devices.\n", MTD_CHAR_MAJOR
);
1254 ret
= register_filesystem(&mtd_inodefs_type
);
1256 pr_notice("Can't register mtd_inodefs filesystem: %d\n", ret
);
1257 goto err_unregister_chdev
;
1261 err_unregister_chdev
:
1262 __unregister_chrdev(MTD_CHAR_MAJOR
, 0, 1 << MINORBITS
, "mtd");
1266 static void __exit
cleanup_mtdchar(void)
1268 unregister_filesystem(&mtd_inodefs_type
);
1269 __unregister_chrdev(MTD_CHAR_MAJOR
, 0, 1 << MINORBITS
, "mtd");
1272 module_init(init_mtdchar
);
1273 module_exit(cleanup_mtdchar
);
1275 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR
);
1277 MODULE_LICENSE("GPL");
1278 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1279 MODULE_DESCRIPTION("Direct character-device access to MTD devices");
1280 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR
);