mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-14 15:54:15 +08:00
98 lines
2.4 KiB
C
98 lines
2.4 KiB
C
/*
|
|
* Simple read-only (writable only for RAM) mtdblock driver
|
|
*
|
|
* Copyright © 2001-2010 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/init.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/mtd/mtd.h>
|
|
#include <linux/mtd/blktrans.h>
|
|
|
|
static int mtdblock_readsect(struct mtd_blktrans_dev *dev,
|
|
unsigned long block, char *buf)
|
|
{
|
|
size_t retlen;
|
|
|
|
if (dev->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 (dev->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 = 31,
|
|
.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");
|