86 lines
1.8 KiB
C
86 lines
1.8 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Simple read-only (writable only for RAM) mtdblock driver
|
|
*
|
|
* Copyright © 2001-2010 David Woodhouse <dwmw2@infradead.org>
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/mtd/mtd.h>
|
|
#include <linux/mtd/blktrans.h>
|
|
#include <linux/module.h>
|
|
#include <linux/major.h>
|
|
|
|
static int mtdblock_readsect(struct mtd_blktrans_dev *dev,
|
|
unsigned long block, char *buf)
|
|
{
|
|
size_t retlen;
|
|
|
|
if (mtd_read(dev->mtd, (block * 512), 512, &retlen, buf))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
static int mtdblock_writesect(struct mtd_blktrans_dev *dev,
|
|
unsigned long block, char *buf)
|
|
{
|
|
size_t retlen;
|
|
|
|
if (mtd_write(dev->mtd, (block * 512), 512, &retlen, buf))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
static void mtdblock_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
|
|
{
|
|
struct mtd_blktrans_dev *dev = kzalloc(sizeof(*dev), GFP_KERNEL);
|
|
|
|
if (!dev)
|
|
return;
|
|
|
|
dev->mtd = mtd;
|
|
dev->devnum = mtd->index;
|
|
|
|
dev->size = mtd->size >> 9;
|
|
dev->tr = tr;
|
|
dev->readonly = 1;
|
|
|
|
if (add_mtd_blktrans_dev(dev))
|
|
kfree(dev);
|
|
}
|
|
|
|
static void mtdblock_remove_dev(struct mtd_blktrans_dev *dev)
|
|
{
|
|
del_mtd_blktrans_dev(dev);
|
|
}
|
|
|
|
static struct mtd_blktrans_ops mtdblock_tr = {
|
|
.name = "mtdblock",
|
|
.major = MTD_BLOCK_MAJOR,
|
|
.part_bits = 0,
|
|
.blksize = 512,
|
|
.readsect = mtdblock_readsect,
|
|
.writesect = mtdblock_writesect,
|
|
.add_mtd = mtdblock_add_mtd,
|
|
.remove_dev = mtdblock_remove_dev,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static int __init mtdblock_init(void)
|
|
{
|
|
return register_mtd_blktrans(&mtdblock_tr);
|
|
}
|
|
|
|
static void __exit mtdblock_exit(void)
|
|
{
|
|
deregister_mtd_blktrans(&mtdblock_tr);
|
|
}
|
|
|
|
module_init(mtdblock_init);
|
|
module_exit(mtdblock_exit);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
|
|
MODULE_DESCRIPTION("Simple read-only block device emulation access to MTD devices");
|