1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
|
/*
* $Id: mtdblock_ro.c,v 1.19 2004/11/16 18:28:59 dwmw2 Exp $
*
* (C) 2003 David Woodhouse <dwmw2@infradead.org>
*
* Simple read-only (writable only for RAM) mtdblock driver
*/
#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 = kmalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return;
memset(dev, 0, sizeof(*dev));
dev->mtd = mtd;
dev->devnum = mtd->index;
dev->blksize = 512;
dev->size = mtd->size >> 9;
dev->tr = tr;
dev->readonly = 1;
add_mtd_blktrans_dev(dev);
}
static void mtdblock_remove_dev(struct mtd_blktrans_dev *dev)
{
del_mtd_blktrans_dev(dev);
kfree(dev);
}
static struct mtd_blktrans_ops mtdblock_tr = {
.name = "mtdblock",
.major = 31,
.part_bits = 0,
.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");
|
