1// SPDX-License-Identifier: GPL-2.0-or-later
 2/*
 3 * Simple read-only (writable only for RAM) mtdblock driver
 4 *
 5 * Copyright © 2001-2010 David Woodhouse <dwmw2@infradead.org>
 6 */
 7
 8#include <linux/init.h>
 9#include <linux/slab.h>
10#include <linux/mtd/mtd.h>
11#include <linux/mtd/blktrans.h>
12#include <linux/module.h>
13#include <linux/major.h>
14
15static int mtdblock_readsect(struct mtd_blktrans_dev *dev,
16			      unsigned long block, char *buf)
17{
18	size_t retlen;
19	int err;
20
21	err = mtd_read(dev->mtd, (block * 512), 512, &retlen, buf);
22	if (err && !mtd_is_bitflip(err))
23		return 1;
24	return 0;
25}
26
27static int mtdblock_writesect(struct mtd_blktrans_dev *dev,
28			      unsigned long block, char *buf)
29{
30	size_t retlen;
31
32	if (mtd_write(dev->mtd, (block * 512), 512, &retlen, buf))
33		return 1;
34	return 0;
35}
36
37static void mtdblock_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
38{
39	struct mtd_blktrans_dev *dev = kzalloc(sizeof(*dev), GFP_KERNEL);
40
41	if (!dev)
42		return;
43
44	dev->mtd = mtd;
45	dev->devnum = mtd->index;
46
47	dev->size = mtd->size >> 9;
48	dev->tr = tr;
49	dev->readonly = 1;
50
51	if (mtd_type_is_nand(mtd))
52		pr_warn_ratelimited("%s: MTD device '%s' is NAND, please consider using UBI block devices instead.\n",
53			tr->name, mtd->name);
54
55	if (add_mtd_blktrans_dev(dev))
56		kfree(dev);
57}
58
59static void mtdblock_remove_dev(struct mtd_blktrans_dev *dev)
60{
61	del_mtd_blktrans_dev(dev);
62}
63
64static struct mtd_blktrans_ops mtdblock_tr = {
65	.name		= "mtdblock",
66	.major		= MTD_BLOCK_MAJOR,
67	.part_bits	= 0,
68	.blksize 	= 512,
69	.readsect	= mtdblock_readsect,
70	.writesect	= mtdblock_writesect,
71	.add_mtd	= mtdblock_add_mtd,
72	.remove_dev	= mtdblock_remove_dev,
73	.owner		= THIS_MODULE,
74};
75
76module_mtd_blktrans(mtdblock_tr);
77
78MODULE_LICENSE("GPL");
79MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
80MODULE_DESCRIPTION("Simple read-only block device emulation access to MTD devices");

 1// SPDX-License-Identifier: GPL-2.0-or-later
 2/*
 3 * Simple read-only (writable only for RAM) mtdblock driver
 4 *
 5 * Copyright © 2001-2010 David Woodhouse <dwmw2@infradead.org>
 6 */
 7
 8#include <linux/init.h>
 9#include <linux/slab.h>
10#include <linux/mtd/mtd.h>
11#include <linux/mtd/blktrans.h>
12#include <linux/module.h>
13#include <linux/major.h>
14
15static int mtdblock_readsect(struct mtd_blktrans_dev *dev,
16			      unsigned long block, char *buf)
17{
18	size_t retlen;
 
19
20	if (mtd_read(dev->mtd, (block * 512), 512, &retlen, buf))
 
21		return 1;
22	return 0;
23}
24
25static int mtdblock_writesect(struct mtd_blktrans_dev *dev,
26			      unsigned long block, char *buf)
27{
28	size_t retlen;
29
30	if (mtd_write(dev->mtd, (block * 512), 512, &retlen, buf))
31		return 1;
32	return 0;
33}
34
35static void mtdblock_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
36{
37	struct mtd_blktrans_dev *dev = kzalloc(sizeof(*dev), GFP_KERNEL);
38
39	if (!dev)
40		return;
41
42	dev->mtd = mtd;
43	dev->devnum = mtd->index;
44
45	dev->size = mtd->size >> 9;
46	dev->tr = tr;
47	dev->readonly = 1;
 
 
 
 
48
49	if (add_mtd_blktrans_dev(dev))
50		kfree(dev);
51}
52
53static void mtdblock_remove_dev(struct mtd_blktrans_dev *dev)
54{
55	del_mtd_blktrans_dev(dev);
56}
57
58static struct mtd_blktrans_ops mtdblock_tr = {
59	.name		= "mtdblock",
60	.major		= MTD_BLOCK_MAJOR,
61	.part_bits	= 0,
62	.blksize 	= 512,
63	.readsect	= mtdblock_readsect,
64	.writesect	= mtdblock_writesect,
65	.add_mtd	= mtdblock_add_mtd,
66	.remove_dev	= mtdblock_remove_dev,
67	.owner		= THIS_MODULE,
68};
69
70module_mtd_blktrans(mtdblock_tr);
71
72MODULE_LICENSE("GPL");
73MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
74MODULE_DESCRIPTION("Simple read-only block device emulation access to MTD devices");