]>
git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - drivers/mtd/mtdchar.c
2 * Character-device access to raw MTD devices.
6 #include <linux/device.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>
16 #include <linux/mtd/mtd.h>
17 #include <linux/mtd/compatmac.h>
19 #include <asm/uaccess.h>
21 static struct class *mtd_class
;
23 static void mtd_notify_add(struct mtd_info
* mtd
)
28 device_create(mtd_class
, NULL
, MKDEV(MTD_CHAR_MAJOR
, mtd
->index
*2), "mtd%d", mtd
->index
);
30 device_create(mtd_class
, NULL
,
31 MKDEV(MTD_CHAR_MAJOR
, mtd
->index
*2+1), "mtd%dro", mtd
->index
);
34 static void mtd_notify_remove(struct mtd_info
* mtd
)
39 device_destroy(mtd_class
, MKDEV(MTD_CHAR_MAJOR
, mtd
->index
*2));
40 device_destroy(mtd_class
, MKDEV(MTD_CHAR_MAJOR
, mtd
->index
*2+1));
43 static struct mtd_notifier notifier
= {
44 .add
= mtd_notify_add
,
45 .remove
= mtd_notify_remove
,
49 * Data structure to hold the pointer to the mtd device as well
50 * as mode information ofr various use cases.
52 struct mtd_file_info
{
54 enum mtd_file_modes mode
;
57 static loff_t
mtd_lseek (struct file
*file
, loff_t offset
, int orig
)
59 struct mtd_file_info
*mfi
= file
->private_data
;
60 struct mtd_info
*mtd
= mfi
->mtd
;
66 offset
+= file
->f_pos
;
75 if (offset
>= 0 && offset
<= mtd
->size
)
76 return file
->f_pos
= offset
;
83 static int mtd_open(struct inode
*inode
, struct file
*file
)
85 int minor
= iminor(inode
);
86 int devnum
= minor
>> 1;
88 struct mtd_file_info
*mfi
;
90 DEBUG(MTD_DEBUG_LEVEL0
, "MTD_open\n");
92 if (devnum
>= MAX_MTD_DEVICES
)
95 /* You can't open the RO devices RW */
96 if ((file
->f_mode
& 2) && (minor
& 1))
99 mtd
= get_mtd_device(NULL
, devnum
);
104 if (MTD_ABSENT
== mtd
->type
) {
109 /* You can't open it RW if it's not a writeable device */
110 if ((file
->f_mode
& 2) && !(mtd
->flags
& MTD_WRITEABLE
)) {
115 mfi
= kzalloc(sizeof(*mfi
), GFP_KERNEL
);
121 file
->private_data
= mfi
;
126 /*====================================================================*/
128 static int mtd_close(struct inode
*inode
, struct file
*file
)
130 struct mtd_file_info
*mfi
= file
->private_data
;
131 struct mtd_info
*mtd
= mfi
->mtd
;
133 DEBUG(MTD_DEBUG_LEVEL0
, "MTD_close\n");
135 /* Only sync if opened RW */
136 if ((file
->f_mode
& 2) && mtd
->sync
)
140 file
->private_data
= NULL
;
146 /* FIXME: This _really_ needs to die. In 2.5, we should lock the
147 userspace buffer down and use it directly with readv/writev.
149 #define MAX_KMALLOC_SIZE 0x20000
151 static ssize_t
mtd_read(struct file
*file
, char __user
*buf
, size_t count
,loff_t
*ppos
)
153 struct mtd_file_info
*mfi
= file
->private_data
;
154 struct mtd_info
*mtd
= mfi
->mtd
;
156 size_t total_retlen
=0;
161 DEBUG(MTD_DEBUG_LEVEL0
,"MTD_read\n");
163 if (*ppos
+ count
> mtd
->size
)
164 count
= mtd
->size
- *ppos
;
169 /* FIXME: Use kiovec in 2.5 to lock down the user's buffers
170 and pass them directly to the MTD functions */
172 if (count
> MAX_KMALLOC_SIZE
)
173 kbuf
=kmalloc(MAX_KMALLOC_SIZE
, GFP_KERNEL
);
175 kbuf
=kmalloc(count
, GFP_KERNEL
);
182 if (count
> MAX_KMALLOC_SIZE
)
183 len
= MAX_KMALLOC_SIZE
;
188 case MTD_MODE_OTP_FACTORY
:
189 ret
= mtd
->read_fact_prot_reg(mtd
, *ppos
, len
, &retlen
, kbuf
);
191 case MTD_MODE_OTP_USER
:
192 ret
= mtd
->read_user_prot_reg(mtd
, *ppos
, len
, &retlen
, kbuf
);
196 struct mtd_oob_ops ops
;
198 ops
.mode
= MTD_OOB_RAW
;
203 ret
= mtd
->read_oob(mtd
, *ppos
, &ops
);
208 ret
= mtd
->read(mtd
, *ppos
, len
, &retlen
, kbuf
);
210 /* Nand returns -EBADMSG on ecc errors, but it returns
211 * the data. For our userspace tools it is important
212 * to dump areas with ecc errors !
213 * For kernel internal usage it also might return -EUCLEAN
214 * to signal the caller that a bitflip has occured and has
215 * been corrected by the ECC algorithm.
216 * Userspace software which accesses NAND this way
217 * must be aware of the fact that it deals with NAND
219 if (!ret
|| (ret
== -EUCLEAN
) || (ret
== -EBADMSG
)) {
221 if (copy_to_user(buf
, kbuf
, retlen
)) {
226 total_retlen
+= retlen
;
244 static ssize_t
mtd_write(struct file
*file
, const char __user
*buf
, size_t count
,loff_t
*ppos
)
246 struct mtd_file_info
*mfi
= file
->private_data
;
247 struct mtd_info
*mtd
= mfi
->mtd
;
250 size_t total_retlen
=0;
254 DEBUG(MTD_DEBUG_LEVEL0
,"MTD_write\n");
256 if (*ppos
== mtd
->size
)
259 if (*ppos
+ count
> mtd
->size
)
260 count
= mtd
->size
- *ppos
;
265 if (count
> MAX_KMALLOC_SIZE
)
266 kbuf
=kmalloc(MAX_KMALLOC_SIZE
, GFP_KERNEL
);
268 kbuf
=kmalloc(count
, GFP_KERNEL
);
275 if (count
> MAX_KMALLOC_SIZE
)
276 len
= MAX_KMALLOC_SIZE
;
280 if (copy_from_user(kbuf
, buf
, len
)) {
286 case MTD_MODE_OTP_FACTORY
:
289 case MTD_MODE_OTP_USER
:
290 if (!mtd
->write_user_prot_reg
) {
294 ret
= mtd
->write_user_prot_reg(mtd
, *ppos
, len
, &retlen
, kbuf
);
299 struct mtd_oob_ops ops
;
301 ops
.mode
= MTD_OOB_RAW
;
306 ret
= mtd
->write_oob(mtd
, *ppos
, &ops
);
312 ret
= (*(mtd
->write
))(mtd
, *ppos
, len
, &retlen
, kbuf
);
316 total_retlen
+= retlen
;
330 /*======================================================================
332 IOCTL calls for getting device parameters.
334 ======================================================================*/
335 static void mtdchar_erase_callback (struct erase_info
*instr
)
337 wake_up((wait_queue_head_t
*)instr
->priv
);
340 #if defined(CONFIG_MTD_OTP) || defined(CONFIG_MTD_ONENAND_OTP)
341 static int otp_select_filemode(struct mtd_file_info
*mfi
, int mode
)
343 struct mtd_info
*mtd
= mfi
->mtd
;
347 case MTD_OTP_FACTORY
:
348 if (!mtd
->read_fact_prot_reg
)
351 mfi
->mode
= MTD_MODE_OTP_FACTORY
;
354 if (!mtd
->read_fact_prot_reg
)
357 mfi
->mode
= MTD_MODE_OTP_USER
;
367 # define otp_select_filemode(f,m) -EOPNOTSUPP
370 static int mtd_ioctl(struct inode
*inode
, struct file
*file
,
371 u_int cmd
, u_long arg
)
373 struct mtd_file_info
*mfi
= file
->private_data
;
374 struct mtd_info
*mtd
= mfi
->mtd
;
375 void __user
*argp
= (void __user
*)arg
;
378 struct mtd_info_user info
;
380 DEBUG(MTD_DEBUG_LEVEL0
, "MTD_ioctl\n");
382 size
= (cmd
& IOCSIZE_MASK
) >> IOCSIZE_SHIFT
;
384 if (!access_ok(VERIFY_READ
, argp
, size
))
388 if (!access_ok(VERIFY_WRITE
, argp
, size
))
393 case MEMGETREGIONCOUNT
:
394 if (copy_to_user(argp
, &(mtd
->numeraseregions
), sizeof(int)))
398 case MEMGETREGIONINFO
:
400 struct region_info_user ur
;
402 if (copy_from_user(&ur
, argp
, sizeof(struct region_info_user
)))
405 if (ur
.regionindex
>= mtd
->numeraseregions
)
407 if (copy_to_user(argp
, &(mtd
->eraseregions
[ur
.regionindex
]),
408 sizeof(struct mtd_erase_region_info
)))
414 info
.type
= mtd
->type
;
415 info
.flags
= mtd
->flags
;
416 info
.size
= mtd
->size
;
417 info
.erasesize
= mtd
->erasesize
;
418 info
.writesize
= mtd
->writesize
;
419 info
.oobsize
= mtd
->oobsize
;
420 /* The below fields are obsolete */
423 if (copy_to_user(argp
, &info
, sizeof(struct mtd_info_user
)))
429 struct erase_info
*erase
;
431 if(!(file
->f_mode
& 2))
434 erase
=kzalloc(sizeof(struct erase_info
),GFP_KERNEL
);
438 wait_queue_head_t waitq
;
439 DECLARE_WAITQUEUE(wait
, current
);
441 init_waitqueue_head(&waitq
);
443 if (copy_from_user(&erase
->addr
, argp
,
444 sizeof(struct erase_info_user
))) {
449 erase
->callback
= mtdchar_erase_callback
;
450 erase
->priv
= (unsigned long)&waitq
;
453 FIXME: Allow INTERRUPTIBLE. Which means
454 not having the wait_queue head on the stack.
456 If the wq_head is on the stack, and we
457 leave because we got interrupted, then the
458 wq_head is no longer there when the
459 callback routine tries to wake us up.
461 ret
= mtd
->erase(mtd
, erase
);
463 set_current_state(TASK_UNINTERRUPTIBLE
);
464 add_wait_queue(&waitq
, &wait
);
465 if (erase
->state
!= MTD_ERASE_DONE
&&
466 erase
->state
!= MTD_ERASE_FAILED
)
468 remove_wait_queue(&waitq
, &wait
);
469 set_current_state(TASK_RUNNING
);
471 ret
= (erase
->state
== MTD_ERASE_FAILED
)?-EIO
:0;
480 struct mtd_oob_buf buf
;
481 struct mtd_oob_ops ops
;
482 struct mtd_oob_buf __user
*user_buf
= argp
;
485 if(!(file
->f_mode
& 2))
488 if (copy_from_user(&buf
, argp
, sizeof(struct mtd_oob_buf
)))
491 if (buf
.length
> 4096)
497 ret
= access_ok(VERIFY_READ
, buf
.ptr
,
498 buf
.length
) ? 0 : EFAULT
;
503 ops
.ooblen
= buf
.length
;
504 ops
.ooboffs
= buf
.start
& (mtd
->oobsize
- 1);
506 ops
.mode
= MTD_OOB_PLACE
;
508 if (ops
.ooboffs
&& ops
.ooblen
> (mtd
->oobsize
- ops
.ooboffs
))
511 ops
.oobbuf
= kmalloc(buf
.length
, GFP_KERNEL
);
515 if (copy_from_user(ops
.oobbuf
, buf
.ptr
, buf
.length
)) {
520 buf
.start
&= ~(mtd
->oobsize
- 1);
521 ret
= mtd
->write_oob(mtd
, buf
.start
, &ops
);
523 if (ops
.oobretlen
> 0xFFFFFFFFU
)
525 retlen
= ops
.oobretlen
;
526 if (copy_to_user(&user_buf
->length
, &retlen
, sizeof(buf
.length
)))
536 struct mtd_oob_buf buf
;
537 struct mtd_oob_ops ops
;
539 if (copy_from_user(&buf
, argp
, sizeof(struct mtd_oob_buf
)))
542 if (buf
.length
> 4096)
548 ret
= access_ok(VERIFY_WRITE
, buf
.ptr
,
549 buf
.length
) ? 0 : -EFAULT
;
553 ops
.ooblen
= buf
.length
;
554 ops
.ooboffs
= buf
.start
& (mtd
->oobsize
- 1);
556 ops
.mode
= MTD_OOB_PLACE
;
558 if (ops
.ooboffs
&& ops
.ooblen
> (mtd
->oobsize
- ops
.ooboffs
))
561 ops
.oobbuf
= kmalloc(buf
.length
, GFP_KERNEL
);
565 buf
.start
&= ~(mtd
->oobsize
- 1);
566 ret
= mtd
->read_oob(mtd
, buf
.start
, &ops
);
568 if (put_user(ops
.oobretlen
, (uint32_t __user
*)argp
))
570 else if (ops
.oobretlen
&& copy_to_user(buf
.ptr
, ops
.oobbuf
,
580 struct erase_info_user einfo
;
582 if (copy_from_user(&einfo
, argp
, sizeof(einfo
)))
588 ret
= mtd
->lock(mtd
, einfo
.start
, einfo
.length
);
594 struct erase_info_user einfo
;
596 if (copy_from_user(&einfo
, argp
, sizeof(einfo
)))
602 ret
= mtd
->unlock(mtd
, einfo
.start
, einfo
.length
);
606 /* Legacy interface */
609 struct nand_oobinfo oi
;
613 if (mtd
->ecclayout
->eccbytes
> ARRAY_SIZE(oi
.eccpos
))
616 oi
.useecc
= MTD_NANDECC_AUTOPLACE
;
617 memcpy(&oi
.eccpos
, mtd
->ecclayout
->eccpos
, sizeof(oi
.eccpos
));
618 memcpy(&oi
.oobfree
, mtd
->ecclayout
->oobfree
,
620 oi
.eccbytes
= mtd
->ecclayout
->eccbytes
;
622 if (copy_to_user(argp
, &oi
, sizeof(struct nand_oobinfo
)))
631 if (copy_from_user(&offs
, argp
, sizeof(loff_t
)))
633 if (!mtd
->block_isbad
)
636 return mtd
->block_isbad(mtd
, offs
);
644 if (copy_from_user(&offs
, argp
, sizeof(loff_t
)))
646 if (!mtd
->block_markbad
)
649 return mtd
->block_markbad(mtd
, offs
);
653 #if defined(CONFIG_MTD_OTP) || defined(CONFIG_MTD_ONENAND_OTP)
657 if (copy_from_user(&mode
, argp
, sizeof(int)))
660 mfi
->mode
= MTD_MODE_NORMAL
;
662 ret
= otp_select_filemode(mfi
, mode
);
668 case OTPGETREGIONCOUNT
:
669 case OTPGETREGIONINFO
:
671 struct otp_info
*buf
= kmalloc(4096, GFP_KERNEL
);
676 case MTD_MODE_OTP_FACTORY
:
677 if (mtd
->get_fact_prot_info
)
678 ret
= mtd
->get_fact_prot_info(mtd
, buf
, 4096);
680 case MTD_MODE_OTP_USER
:
681 if (mtd
->get_user_prot_info
)
682 ret
= mtd
->get_user_prot_info(mtd
, buf
, 4096);
688 if (cmd
== OTPGETREGIONCOUNT
) {
689 int nbr
= ret
/ sizeof(struct otp_info
);
690 ret
= copy_to_user(argp
, &nbr
, sizeof(int));
692 ret
= copy_to_user(argp
, buf
, ret
);
702 struct otp_info oinfo
;
704 if (mfi
->mode
!= MTD_MODE_OTP_USER
)
706 if (copy_from_user(&oinfo
, argp
, sizeof(oinfo
)))
708 if (!mtd
->lock_user_prot_reg
)
710 ret
= mtd
->lock_user_prot_reg(mtd
, oinfo
.start
, oinfo
.length
);
720 if (copy_to_user(argp
, mtd
->ecclayout
,
721 sizeof(struct nand_ecclayout
)))
728 if (copy_to_user(argp
, &mtd
->ecc_stats
,
729 sizeof(struct mtd_ecc_stats
)))
739 case MTD_MODE_OTP_FACTORY
:
740 case MTD_MODE_OTP_USER
:
741 ret
= otp_select_filemode(mfi
, arg
);
745 if (!mtd
->read_oob
|| !mtd
->write_oob
)
749 case MTD_MODE_NORMAL
:
765 static const struct file_operations mtd_fops
= {
766 .owner
= THIS_MODULE
,
772 .release
= mtd_close
,
775 static int __init
init_mtdchar(void)
777 if (register_chrdev(MTD_CHAR_MAJOR
, "mtd", &mtd_fops
)) {
778 printk(KERN_NOTICE
"Can't allocate major number %d for Memory Technology Devices.\n",
783 mtd_class
= class_create(THIS_MODULE
, "mtd");
785 if (IS_ERR(mtd_class
)) {
786 printk(KERN_ERR
"Error creating mtd class.\n");
787 unregister_chrdev(MTD_CHAR_MAJOR
, "mtd");
788 return PTR_ERR(mtd_class
);
791 register_mtd_user(¬ifier
);
795 static void __exit
cleanup_mtdchar(void)
797 unregister_mtd_user(¬ifier
);
798 class_destroy(mtd_class
);
799 unregister_chrdev(MTD_CHAR_MAJOR
, "mtd");
802 module_init(init_mtdchar
);
803 module_exit(cleanup_mtdchar
);
806 MODULE_LICENSE("GPL");
807 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
808 MODULE_DESCRIPTION("Direct character-device access to MTD devices");