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660685d9d1
linux/drivers/mtd/mtdchar.c
Artem Bityutskiy 660685d9d1 mtd: merge mtdchar module with mtdcore 
The MTD subsystem has historically tried to be as configurable as possible. The
side-effect of this is that its configuration menu is rather large, and we are
gradually shrinking it. For example, we recently merged partitions support with
the mtdcore.

This patch does the next step - it merges the mtdchar module to mtdcore. And in
this case this is not only about eliminating too fine-grained separation and
simplifying the configuration menu. This is also about eliminating seemingly
useless kernel module.

Indeed, mtdchar is a module that allows user-space making use of MTD devices
via /dev/mtd* character devices. If users do not enable it, they simply cannot
use MTD devices at all. They cannot read or write the flash contents. Is it a
sane and useful setup? I believe not. And everyone just enables mtdchar.

Having mtdchar separate is also a little bit harmful. People sometimes miss the
fact that they need to enable an additional configuration option to have
user-space MTD interfaces, and then they wonder why on earth the kernel does
not allow using the flash? They spend time asking around.

Thus, let's just get rid of this module and make it part of mtd core.

Note, mtdchar had additional configuration option to enable OTP interfaces,
which are present on some flashes. I removed that option as well - it saves a
really tiny amount space.

[dwmw2: Strictly speaking, you can mount file systems on MTD devices just
        fine without the mtdchar (or mtdblock) devices; you just can't do
        other manipulations directly on the underlying device. But still I
        agree that it makes sense to make this unconditional. And Yay! we
        get to kill off an instance of checking CONFIG_foo_MODULE, which is
        an abomination that should never happen.]

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2013-04-05 13:16:54 +01:00

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/*
* Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/mutex.h>
#include <linux/backing-dev.h>
#include <linux/compat.h>
#include <linux/mount.h>
#include <linux/blkpg.h>
#include <linux/magic.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/mtd/map.h>
#include <asm/uaccess.h>
#include "mtdcore.h"
static DEFINE_MUTEX(mtd_mutex);
/*
* Data structure to hold the pointer to the mtd device as well
* as mode information of various use cases.
*/
struct mtd_file_info {
struct mtd_info *mtd;
struct inode *ino;
enum mtd_file_modes mode;
};
static loff_t mtdchar_lseek(struct file *file, loff_t offset, int orig)
{
struct mtd_file_info *mfi = file->private_data;
struct mtd_info *mtd = mfi->mtd;
switch (orig) {
case SEEK_SET:
break;
case SEEK_CUR:
offset += file->f_pos;
break;
case SEEK_END:
offset += mtd->size;
break;
default:
return -EINVAL;
}
if (offset >= 0 && offset <= mtd->size)
return file->f_pos = offset;
return -EINVAL;
}
static int count;
static struct vfsmount *mnt;
static struct file_system_type mtd_inodefs_type;
static int mtdchar_open(struct inode *inode, struct file *file)
{
int minor = iminor(inode);
int devnum = minor >> 1;
int ret = 0;
struct mtd_info *mtd;
struct mtd_file_info *mfi;
struct inode *mtd_ino;
pr_debug("MTD_open\n");
/* You can't open the RO devices RW */
if ((file->f_mode & FMODE_WRITE) && (minor & 1))
return -EACCES;
ret = simple_pin_fs(&mtd_inodefs_type, &mnt, &count);
if (ret)
return ret;
mutex_lock(&mtd_mutex);
mtd = get_mtd_device(NULL, devnum);
if (IS_ERR(mtd)) {
ret = PTR_ERR(mtd);
goto out;
}
if (mtd->type == MTD_ABSENT) {
ret = -ENODEV;
goto out1;
}
mtd_ino = iget_locked(mnt->mnt_sb, devnum);
if (!mtd_ino) {
ret = -ENOMEM;
goto out1;
}
if (mtd_ino->i_state & I_NEW) {
mtd_ino->i_private = mtd;
mtd_ino->i_mode = S_IFCHR;
mtd_ino->i_data.backing_dev_info = mtd->backing_dev_info;
unlock_new_inode(mtd_ino);
}
file->f_mapping = mtd_ino->i_mapping;
/* You can't open it RW if it's not a writeable device */
if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
ret = -EACCES;
goto out2;
}
mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
if (!mfi) {
ret = -ENOMEM;
goto out2;
}
mfi->ino = mtd_ino;
mfi->mtd = mtd;
file->private_data = mfi;
mutex_unlock(&mtd_mutex);
return 0;
out2:
iput(mtd_ino);
out1:
put_mtd_device(mtd);
out:
mutex_unlock(&mtd_mutex);
simple_release_fs(&mnt, &count);
return ret;
} /* mtdchar_open */
/*====================================================================*/
static int mtdchar_close(struct inode *inode, struct file *file)
{
struct mtd_file_info *mfi = file->private_data;
struct mtd_info *mtd = mfi->mtd;
pr_debug("MTD_close\n");
/* Only sync if opened RW */
if ((file->f_mode & FMODE_WRITE))
mtd_sync(mtd);
iput(mfi->ino);
put_mtd_device(mtd);
file->private_data = NULL;
kfree(mfi);
simple_release_fs(&mnt, &count);
return 0;
} /* mtdchar_close */
/* Back in June 2001, dwmw2 wrote:
*
* FIXME: This _really_ needs to die. In 2.5, we should lock the
* userspace buffer down and use it directly with readv/writev.
*
* The implementation below, using mtd_kmalloc_up_to, mitigates
* allocation failures when the system is under low-memory situations
* or if memory is highly fragmented at the cost of reducing the
* performance of the requested transfer due to a smaller buffer size.
*
* A more complex but more memory-efficient implementation based on
* get_user_pages and iovecs to cover extents of those pages is a
* longer-term goal, as intimated by dwmw2 above. However, for the
* write case, this requires yet more complex head and tail transfer
* handling when those head and tail offsets and sizes are such that
* alignment requirements are not met in the NAND subdriver.
*/
static ssize_t mtdchar_read(struct file *file, char __user *buf, size_t count,
loff_t *ppos)
{
struct mtd_file_info *mfi = file->private_data;
struct mtd_info *mtd = mfi->mtd;
size_t retlen;
size_t total_retlen=0;
int ret=0;
int len;
size_t size = count;
char *kbuf;
pr_debug("MTD_read\n");
if (*ppos + count > mtd->size)
count = mtd->size - *ppos;
if (!count)
return 0;
kbuf = mtd_kmalloc_up_to(mtd, &size);
if (!kbuf)
return -ENOMEM;
while (count) {
len = min_t(size_t, count, size);
switch (mfi->mode) {
case MTD_FILE_MODE_OTP_FACTORY:
ret = mtd_read_fact_prot_reg(mtd, *ppos, len,
&retlen, kbuf);
break;
case MTD_FILE_MODE_OTP_USER:
ret = mtd_read_user_prot_reg(mtd, *ppos, len,
&retlen, kbuf);
break;
case MTD_FILE_MODE_RAW:
{
struct mtd_oob_ops ops;
ops.mode = MTD_OPS_RAW;
ops.datbuf = kbuf;
ops.oobbuf = NULL;
ops.len = len;
ret = mtd_read_oob(mtd, *ppos, &ops);
retlen = ops.retlen;
break;
}
default:
ret = mtd_read(mtd, *ppos, len, &retlen, kbuf);
}
/* Nand returns -EBADMSG on ECC errors, but it returns
* the data. For our userspace tools it is important
* to dump areas with ECC errors!
* For kernel internal usage it also might return -EUCLEAN
* to signal the caller that a bitflip has occurred and has
* been corrected by the ECC algorithm.
* Userspace software which accesses NAND this way
* must be aware of the fact that it deals with NAND
*/
if (!ret || mtd_is_bitflip_or_eccerr(ret)) {
*ppos += retlen;
if (copy_to_user(buf, kbuf, retlen)) {
kfree(kbuf);
return -EFAULT;
}
else
total_retlen += retlen;
count -= retlen;
buf += retlen;
if (retlen == 0)
count = 0;
}
else {
kfree(kbuf);
return ret;
}
}
kfree(kbuf);
return total_retlen;
} /* mtdchar_read */
static ssize_t mtdchar_write(struct file *file, const char __user *buf, size_t count,
loff_t *ppos)
{
struct mtd_file_info *mfi = file->private_data;
struct mtd_info *mtd = mfi->mtd;
size_t size = count;
char *kbuf;
size_t retlen;
size_t total_retlen=0;
int ret=0;
int len;
pr_debug("MTD_write\n");
if (*ppos == mtd->size)
return -ENOSPC;
if (*ppos + count > mtd->size)
count = mtd->size - *ppos;
if (!count)
return 0;
kbuf = mtd_kmalloc_up_to(mtd, &size);
if (!kbuf)
return -ENOMEM;
while (count) {
len = min_t(size_t, count, size);
if (copy_from_user(kbuf, buf, len)) {
kfree(kbuf);
return -EFAULT;
}
switch (mfi->mode) {
case MTD_FILE_MODE_OTP_FACTORY:
ret = -EROFS;
break;
case MTD_FILE_MODE_OTP_USER:
ret = mtd_write_user_prot_reg(mtd, *ppos, len,
&retlen, kbuf);
break;
case MTD_FILE_MODE_RAW:
{
struct mtd_oob_ops ops;
ops.mode = MTD_OPS_RAW;
ops.datbuf = kbuf;
ops.oobbuf = NULL;
ops.ooboffs = 0;
ops.len = len;
ret = mtd_write_oob(mtd, *ppos, &ops);
retlen = ops.retlen;
break;
}
default:
ret = mtd_write(mtd, *ppos, len, &retlen, kbuf);
}
if (!ret) {
*ppos += retlen;
total_retlen += retlen;
count -= retlen;
buf += retlen;
}
else {
kfree(kbuf);
return ret;
}
}
kfree(kbuf);
return total_retlen;
} /* mtdchar_write */
/*======================================================================
IOCTL calls for getting device parameters.
======================================================================*/
static void mtdchar_erase_callback (struct erase_info *instr)
{
wake_up((wait_queue_head_t *)instr->priv);
}
static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
{
struct mtd_info *mtd = mfi->mtd;
size_t retlen;
switch (mode) {
case MTD_OTP_FACTORY:
if (mtd_read_fact_prot_reg(mtd, -1, 0, &retlen, NULL) ==
-EOPNOTSUPP)
return -EOPNOTSUPP;
mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
break;
case MTD_OTP_USER:
if (mtd_read_user_prot_reg(mtd, -1, 0, &retlen, NULL) ==
-EOPNOTSUPP)
return -EOPNOTSUPP;
mfi->mode = MTD_FILE_MODE_OTP_USER;
break;
case MTD_OTP_OFF:
mfi->mode = MTD_FILE_MODE_NORMAL;
break;
default:
return -EINVAL;
}
return 0;
}
static int mtdchar_writeoob(struct file *file, struct mtd_info *mtd,
uint64_t start, uint32_t length, void __user *ptr,
uint32_t __user *retp)
{
struct mtd_file_info *mfi = file->private_data;
struct mtd_oob_ops ops;
uint32_t retlen;
int ret = 0;
if (!(file->f_mode & FMODE_WRITE))
return -EPERM;
if (length > 4096)
return -EINVAL;
if (!mtd->_write_oob)
ret = -EOPNOTSUPP;
else
ret = access_ok(VERIFY_READ, ptr, length) ? 0 : -EFAULT;
if (ret)
return ret;
ops.ooblen = length;
ops.ooboffs = start & (mtd->writesize - 1);
ops.datbuf = NULL;
ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
MTD_OPS_PLACE_OOB;
if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
return -EINVAL;
ops.oobbuf = memdup_user(ptr, length);
if (IS_ERR(ops.oobbuf))
return PTR_ERR(ops.oobbuf);
start &= ~((uint64_t)mtd->writesize - 1);
ret = mtd_write_oob(mtd, start, &ops);
if (ops.oobretlen > 0xFFFFFFFFU)
ret = -EOVERFLOW;
retlen = ops.oobretlen;
if (copy_to_user(retp, &retlen, sizeof(length)))
ret = -EFAULT;
kfree(ops.oobbuf);
return ret;
}
static int mtdchar_readoob(struct file *file, struct mtd_info *mtd,
uint64_t start, uint32_t length, void __user *ptr,
uint32_t __user *retp)
{
struct mtd_file_info *mfi = file->private_data;
struct mtd_oob_ops ops;
int ret = 0;
if (length > 4096)
return -EINVAL;
if (!access_ok(VERIFY_WRITE, ptr, length))
return -EFAULT;
ops.ooblen = length;
ops.ooboffs = start & (mtd->writesize - 1);
ops.datbuf = NULL;
ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
MTD_OPS_PLACE_OOB;
if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
return -EINVAL;
ops.oobbuf = kmalloc(length, GFP_KERNEL);
if (!ops.oobbuf)
return -ENOMEM;
start &= ~((uint64_t)mtd->writesize - 1);
ret = mtd_read_oob(mtd, start, &ops);
if (put_user(ops.oobretlen, retp))
ret = -EFAULT;
else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
ops.oobretlen))
ret = -EFAULT;
kfree(ops.oobbuf);
/*
* NAND returns -EBADMSG on ECC errors, but it returns the OOB
* data. For our userspace tools it is important to dump areas
* with ECC errors!
* For kernel internal usage it also might return -EUCLEAN
* to signal the caller that a bitflip has occured and has
* been corrected by the ECC algorithm.
*
* Note: currently the standard NAND function, nand_read_oob_std,
* does not calculate ECC for the OOB area, so do not rely on
* this behavior unless you have replaced it with your own.
*/
if (mtd_is_bitflip_or_eccerr(ret))
return 0;
return ret;
}
/*
* Copies (and truncates, if necessary) data from the larger struct,
* nand_ecclayout, to the smaller, deprecated layout struct,
* nand_ecclayout_user. This is necessary only to support the deprecated
* API ioctl ECCGETLAYOUT while allowing all new functionality to use
* nand_ecclayout flexibly (i.e. the struct may change size in new
* releases without requiring major rewrites).
*/
static int shrink_ecclayout(const struct nand_ecclayout *from,
struct nand_ecclayout_user *to)
{
int i;
if (!from || !to)
return -EINVAL;
memset(to, 0, sizeof(*to));
to->eccbytes = min((int)from->eccbytes, MTD_MAX_ECCPOS_ENTRIES);
for (i = 0; i < to->eccbytes; i++)
to->eccpos[i] = from->eccpos[i];
for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
if (from->oobfree[i].length == 0 &&
from->oobfree[i].offset == 0)
break;
to->oobavail += from->oobfree[i].length;
to->oobfree[i] = from->oobfree[i];
}
return 0;
}
static int mtdchar_blkpg_ioctl(struct mtd_info *mtd,
struct blkpg_ioctl_arg __user *arg)
{
struct blkpg_ioctl_arg a;
struct blkpg_partition p;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
return -EFAULT;
if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
return -EFAULT;
switch (a.op) {
case BLKPG_ADD_PARTITION:
/* Only master mtd device must be used to add partitions */
if (mtd_is_partition(mtd))
return -EINVAL;
return mtd_add_partition(mtd, p.devname, p.start, p.length);
case BLKPG_DEL_PARTITION:
if (p.pno < 0)
return -EINVAL;
return mtd_del_partition(mtd, p.pno);
default:
return -EINVAL;
}
}
static int mtdchar_write_ioctl(struct mtd_info *mtd,
struct mtd_write_req __user *argp)
{
struct mtd_write_req req;
struct mtd_oob_ops ops;
void __user *usr_data, *usr_oob;
int ret;
if (copy_from_user(&req, argp, sizeof(req)) ||
!access_ok(VERIFY_READ, req.usr_data, req.len) ||
!access_ok(VERIFY_READ, req.usr_oob, req.ooblen))
return -EFAULT;
if (!mtd->_write_oob)
return -EOPNOTSUPP;
ops.mode = req.mode;
ops.len = (size_t)req.len;
ops.ooblen = (size_t)req.ooblen;
ops.ooboffs = 0;
usr_data = (void __user *)(uintptr_t)req.usr_data;
usr_oob = (void __user *)(uintptr_t)req.usr_oob;
if (req.usr_data) {
ops.datbuf = memdup_user(usr_data, ops.len);
if (IS_ERR(ops.datbuf))
return PTR_ERR(ops.datbuf);
} else {
ops.datbuf = NULL;
}
if (req.usr_oob) {
ops.oobbuf = memdup_user(usr_oob, ops.ooblen);
if (IS_ERR(ops.oobbuf)) {
kfree(ops.datbuf);
return PTR_ERR(ops.oobbuf);
}
} else {
ops.oobbuf = NULL;
}
ret = mtd_write_oob(mtd, (loff_t)req.start, &ops);
kfree(ops.datbuf);
kfree(ops.oobbuf);
return ret;
}
static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
{
struct mtd_file_info *mfi = file->private_data;
struct mtd_info *mtd = mfi->mtd;
void __user *argp = (void __user *)arg;
int ret = 0;
u_long size;
struct mtd_info_user info;
pr_debug("MTD_ioctl\n");
size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
if (cmd & IOC_IN) {
if (!access_ok(VERIFY_READ, argp, size))
return -EFAULT;
}
if (cmd & IOC_OUT) {
if (!access_ok(VERIFY_WRITE, argp, size))
return -EFAULT;
}
switch (cmd) {
case MEMGETREGIONCOUNT:
if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
return -EFAULT;
break;
case MEMGETREGIONINFO:
{
uint32_t ur_idx;
struct mtd_erase_region_info *kr;
struct region_info_user __user *ur = argp;
if (get_user(ur_idx, &(ur->regionindex)))
return -EFAULT;
if (ur_idx >= mtd->numeraseregions)
return -EINVAL;
kr = &(mtd->eraseregions[ur_idx]);
if (put_user(kr->offset, &(ur->offset))
|| put_user(kr->erasesize, &(ur->erasesize))
|| put_user(kr->numblocks, &(ur->numblocks)))
return -EFAULT;
break;
}
case MEMGETINFO:
memset(&info, 0, sizeof(info));
info.type = mtd->type;
info.flags = mtd->flags;
info.size = mtd->size;
info.erasesize = mtd->erasesize;
info.writesize = mtd->writesize;
info.oobsize = mtd->oobsize;
/* The below field is obsolete */
info.padding = 0;
if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
return -EFAULT;
break;
case MEMERASE:
case MEMERASE64:
{
struct erase_info *erase;
if(!(file->f_mode & FMODE_WRITE))
return -EPERM;
erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
if (!erase)
ret = -ENOMEM;
else {
wait_queue_head_t waitq;
DECLARE_WAITQUEUE(wait, current);
init_waitqueue_head(&waitq);
if (cmd == MEMERASE64) {
struct erase_info_user64 einfo64;
if (copy_from_user(&einfo64, argp,
sizeof(struct erase_info_user64))) {
kfree(erase);
return -EFAULT;
}
erase->addr = einfo64.start;
erase->len = einfo64.length;
} else {
struct erase_info_user einfo32;
if (copy_from_user(&einfo32, argp,
sizeof(struct erase_info_user))) {
kfree(erase);
return -EFAULT;
}
erase->addr = einfo32.start;
erase->len = einfo32.length;
}
erase->mtd = mtd;
erase->callback = mtdchar_erase_callback;
erase->priv = (unsigned long)&waitq;
/*
FIXME: Allow INTERRUPTIBLE. Which means
not having the wait_queue head on the stack.
If the wq_head is on the stack, and we
leave because we got interrupted, then the
wq_head is no longer there when the
callback routine tries to wake us up.
*/
ret = mtd_erase(mtd, erase);
if (!ret) {
set_current_state(TASK_UNINTERRUPTIBLE);
add_wait_queue(&waitq, &wait);
if (erase->state != MTD_ERASE_DONE &&
erase->state != MTD_ERASE_FAILED)
schedule();
remove_wait_queue(&waitq, &wait);
set_current_state(TASK_RUNNING);
ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
}
kfree(erase);
}
break;
}
case MEMWRITEOOB:
{
struct mtd_oob_buf buf;
struct mtd_oob_buf __user *buf_user = argp;
/* NOTE: writes return length to buf_user->length */
if (copy_from_user(&buf, argp, sizeof(buf)))
ret = -EFAULT;
else
ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
buf.ptr, &buf_user->length);
break;
}
case MEMREADOOB:
{
struct mtd_oob_buf buf;
struct mtd_oob_buf __user *buf_user = argp;
/* NOTE: writes return length to buf_user->start */
if (copy_from_user(&buf, argp, sizeof(buf)))
ret = -EFAULT;
else
ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
buf.ptr, &buf_user->start);
break;
}
case MEMWRITEOOB64:
{
struct mtd_oob_buf64 buf;
struct mtd_oob_buf64 __user *buf_user = argp;
if (copy_from_user(&buf, argp, sizeof(buf)))
ret = -EFAULT;
else
ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
(void __user *)(uintptr_t)buf.usr_ptr,
&buf_user->length);
break;
}
case MEMREADOOB64:
{
struct mtd_oob_buf64 buf;
struct mtd_oob_buf64 __user *buf_user = argp;
if (copy_from_user(&buf, argp, sizeof(buf)))
ret = -EFAULT;
else
ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
(void __user *)(uintptr_t)buf.usr_ptr,
&buf_user->length);
break;
}
case MEMWRITE:
{
ret = mtdchar_write_ioctl(mtd,
(struct mtd_write_req __user *)arg);
break;
}
case MEMLOCK:
{
struct erase_info_user einfo;
if (copy_from_user(&einfo, argp, sizeof(einfo)))
return -EFAULT;
ret = mtd_lock(mtd, einfo.start, einfo.length);
break;
}
case MEMUNLOCK:
{
struct erase_info_user einfo;
if (copy_from_user(&einfo, argp, sizeof(einfo)))
return -EFAULT;
ret = mtd_unlock(mtd, einfo.start, einfo.length);
break;
}
case MEMISLOCKED:
{
struct erase_info_user einfo;
if (copy_from_user(&einfo, argp, sizeof(einfo)))
return -EFAULT;
ret = mtd_is_locked(mtd, einfo.start, einfo.length);
break;
}
/* Legacy interface */
case MEMGETOOBSEL:
{
struct nand_oobinfo oi;
if (!mtd->ecclayout)
return -EOPNOTSUPP;
if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
return -EINVAL;
oi.useecc = MTD_NANDECC_AUTOPLACE;
memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
sizeof(oi.oobfree));
oi.eccbytes = mtd->ecclayout->eccbytes;
if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
return -EFAULT;
break;
}
case MEMGETBADBLOCK:
{
loff_t offs;
if (copy_from_user(&offs, argp, sizeof(loff_t)))
return -EFAULT;
return mtd_block_isbad(mtd, offs);
break;
}
case MEMSETBADBLOCK:
{
loff_t offs;
if (copy_from_user(&offs, argp, sizeof(loff_t)))
return -EFAULT;
return mtd_block_markbad(mtd, offs);
break;
}
case OTPSELECT:
{
int mode;
if (copy_from_user(&mode, argp, sizeof(int)))
return -EFAULT;
mfi->mode = MTD_FILE_MODE_NORMAL;
ret = otp_select_filemode(mfi, mode);
file->f_pos = 0;
break;
}
case OTPGETREGIONCOUNT:
case OTPGETREGIONINFO:
{
struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
if (!buf)
return -ENOMEM;
switch (mfi->mode) {
case MTD_FILE_MODE_OTP_FACTORY:
ret = mtd_get_fact_prot_info(mtd, buf, 4096);
break;
case MTD_FILE_MODE_OTP_USER:
ret = mtd_get_user_prot_info(mtd, buf, 4096);
break;
default:
ret = -EINVAL;
break;
}
if (ret >= 0) {
if (cmd == OTPGETREGIONCOUNT) {
int nbr = ret / sizeof(struct otp_info);
ret = copy_to_user(argp, &nbr, sizeof(int));
} else
ret = copy_to_user(argp, buf, ret);
if (ret)
ret = -EFAULT;
}
kfree(buf);
break;
}
case OTPLOCK:
{
struct otp_info oinfo;
if (mfi->mode != MTD_FILE_MODE_OTP_USER)
return -EINVAL;
if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
return -EFAULT;
ret = mtd_lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
break;
}
/* This ioctl is being deprecated - it truncates the ECC layout */
case ECCGETLAYOUT:
{
struct nand_ecclayout_user *usrlay;
if (!mtd->ecclayout)
return -EOPNOTSUPP;
usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
if (!usrlay)
return -ENOMEM;
shrink_ecclayout(mtd->ecclayout, usrlay);
if (copy_to_user(argp, usrlay, sizeof(*usrlay)))
ret = -EFAULT;
kfree(usrlay);
break;
}
case ECCGETSTATS:
{
if (copy_to_user(argp, &mtd->ecc_stats,
sizeof(struct mtd_ecc_stats)))
return -EFAULT;
break;
}
case MTDFILEMODE:
{
mfi->mode = 0;
switch(arg) {
case MTD_FILE_MODE_OTP_FACTORY:
case MTD_FILE_MODE_OTP_USER:
ret = otp_select_filemode(mfi, arg);
break;
case MTD_FILE_MODE_RAW:
if (!mtd_has_oob(mtd))
return -EOPNOTSUPP;
mfi->mode = arg;
case MTD_FILE_MODE_NORMAL:
break;
default:
ret = -EINVAL;
}
file->f_pos = 0;
break;
}
case BLKPG:
{
ret = mtdchar_blkpg_ioctl(mtd,
(struct blkpg_ioctl_arg __user *)arg);
break;
}
case BLKRRPART:
{
/* No reread partition feature. Just return ok */
ret = 0;
break;
}
default:
ret = -ENOTTY;
}
return ret;
} /* memory_ioctl */
static long mtdchar_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
{
int ret;
mutex_lock(&mtd_mutex);
ret = mtdchar_ioctl(file, cmd, arg);
mutex_unlock(&mtd_mutex);
return ret;
}
#ifdef CONFIG_COMPAT
struct mtd_oob_buf32 {
u_int32_t start;
u_int32_t length;
compat_caddr_t ptr; /* unsigned char* */
};
#define MEMWRITEOOB32 _IOWR('M', 3, struct mtd_oob_buf32)
#define MEMREADOOB32 _IOWR('M', 4, struct mtd_oob_buf32)
static long mtdchar_compat_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
struct mtd_file_info *mfi = file->private_data;
struct mtd_info *mtd = mfi->mtd;
void __user *argp = compat_ptr(arg);
int ret = 0;
mutex_lock(&mtd_mutex);
switch (cmd) {
case MEMWRITEOOB32:
{
struct mtd_oob_buf32 buf;
struct mtd_oob_buf32 __user *buf_user = argp;
if (copy_from_user(&buf, argp, sizeof(buf)))
ret = -EFAULT;
else
ret = mtdchar_writeoob(file, mtd, buf.start,
buf.length, compat_ptr(buf.ptr),
&buf_user->length);
break;
}
case MEMREADOOB32:
{
struct mtd_oob_buf32 buf;
struct mtd_oob_buf32 __user *buf_user = argp;
/* NOTE: writes return length to buf->start */
if (copy_from_user(&buf, argp, sizeof(buf)))
ret = -EFAULT;
else
ret = mtdchar_readoob(file, mtd, buf.start,
buf.length, compat_ptr(buf.ptr),
&buf_user->start);
break;
}
default:
ret = mtdchar_ioctl(file, cmd, (unsigned long)argp);
}
mutex_unlock(&mtd_mutex);
return ret;
}
#endif /* CONFIG_COMPAT */
/*
* try to determine where a shared mapping can be made
* - only supported for NOMMU at the moment (MMU can't doesn't copy private
* mappings)
*/
#ifndef CONFIG_MMU
static unsigned long mtdchar_get_unmapped_area(struct file *file,
unsigned long addr,
unsigned long len,
unsigned long pgoff,
unsigned long flags)
{
struct mtd_file_info *mfi = file->private_data;
struct mtd_info *mtd = mfi->mtd;
unsigned long offset;
int ret;
if (addr != 0)
return (unsigned long) -EINVAL;
if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
return (unsigned long) -EINVAL;
offset = pgoff << PAGE_SHIFT;
if (offset > mtd->size - len)
return (unsigned long) -EINVAL;
ret = mtd_get_unmapped_area(mtd, len, offset, flags);
return ret == -EOPNOTSUPP ? -ENOSYS : ret;
}
#endif
static inline unsigned long get_vm_size(struct vm_area_struct *vma)
{
return vma->vm_end - vma->vm_start;
}
static inline resource_size_t get_vm_offset(struct vm_area_struct *vma)
{
return (resource_size_t) vma->vm_pgoff << PAGE_SHIFT;
}
/*
* Set a new vm offset.
*
* Verify that the incoming offset really works as a page offset,
* and that the offset and size fit in a resource_size_t.
*/
static inline int set_vm_offset(struct vm_area_struct *vma, resource_size_t off)
{
pgoff_t pgoff = off >> PAGE_SHIFT;
if (off != (resource_size_t) pgoff << PAGE_SHIFT)
return -EINVAL;
if (off + get_vm_size(vma) - 1 < off)
return -EINVAL;
vma->vm_pgoff = pgoff;
return 0;
}
/*
* set up a mapping for shared memory segments
*/
static int mtdchar_mmap(struct file *file, struct vm_area_struct *vma)
{
#ifdef CONFIG_MMU
struct mtd_file_info *mfi = file->private_data;
struct mtd_info *mtd = mfi->mtd;
struct map_info *map = mtd->priv;
resource_size_t start, off;
unsigned long len, vma_len;
/* This is broken because it assumes the MTD device is map-based
and that mtd->priv is a valid struct map_info. It should be
replaced with something that uses the mtd_get_unmapped_area()
operation properly. */
if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
off = get_vm_offset(vma);
start = map->phys;
len = PAGE_ALIGN((start & ~PAGE_MASK) + map->size);
start &= PAGE_MASK;
vma_len = get_vm_size(vma);
/* Overflow in off+len? */
if (vma_len + off < off)
return -EINVAL;
/* Does it fit in the mapping? */
if (vma_len + off > len)
return -EINVAL;
off += start;
/* Did that overflow? */
if (off < start)
return -EINVAL;
if (set_vm_offset(vma, off) < 0)
return -EINVAL;
vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
#ifdef pgprot_noncached
if (file->f_flags & O_DSYNC || off >= __pa(high_memory))
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
#endif
if (io_remap_pfn_range(vma, vma->vm_start, off >> PAGE_SHIFT,
vma->vm_end - vma->vm_start,
vma->vm_page_prot))
return -EAGAIN;
return 0;
}
return -ENOSYS;
#else
return vma->vm_flags & VM_SHARED ? 0 : -ENOSYS;
#endif
}
static const struct file_operations mtd_fops = {
.owner = THIS_MODULE,
.llseek = mtdchar_lseek,
.read = mtdchar_read,
.write = mtdchar_write,
.unlocked_ioctl = mtdchar_unlocked_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = mtdchar_compat_ioctl,
#endif
.open = mtdchar_open,
.release = mtdchar_close,
.mmap = mtdchar_mmap,
#ifndef CONFIG_MMU
.get_unmapped_area = mtdchar_get_unmapped_area,
#endif
};
static const struct super_operations mtd_ops = {
.drop_inode = generic_delete_inode,
.statfs = simple_statfs,
};
static struct dentry *mtd_inodefs_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
return mount_pseudo(fs_type, "mtd_inode:", &mtd_ops, NULL, MTD_INODE_FS_MAGIC);
}
static struct file_system_type mtd_inodefs_type = {
.name = "mtd_inodefs",
.mount = mtd_inodefs_mount,
.kill_sb = kill_anon_super,
};
MODULE_ALIAS_FS("mtd_inodefs");
int __init init_mtdchar(void)
{
int ret;
ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
"mtd", &mtd_fops);
if (ret < 0) {
pr_err("Can't allocate major number %d for MTD\n",
MTD_CHAR_MAJOR);
return ret;
}
ret = register_filesystem(&mtd_inodefs_type);
if (ret) {
pr_err("Can't register mtd_inodefs filesystem, error %d\n",
ret);
goto err_unregister_chdev;
}
return ret;
err_unregister_chdev:
__unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
return ret;
}
void __exit cleanup_mtdchar(void)
{
unregister_filesystem(&mtd_inodefs_type);
__unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
}
MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
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