Commit | Line | Data |
---|---|---|
fd534e9b | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 | 2 | /* |
1da177e4 | 3 | * Simple read-only (writable only for RAM) mtdblock driver |
a1452a37 DW |
4 | * |
5 | * Copyright © 2001-2010 David Woodhouse <dwmw2@infradead.org> | |
1da177e4 LT |
6 | */ |
7 | ||
8 | #include <linux/init.h> | |
9 | #include <linux/slab.h> | |
10 | #include <linux/mtd/mtd.h> | |
11 | #include <linux/mtd/blktrans.h> | |
a0e5cc58 | 12 | #include <linux/module.h> |
f83c3838 | 13 | #include <linux/major.h> |
1da177e4 LT |
14 | |
15 | static int mtdblock_readsect(struct mtd_blktrans_dev *dev, | |
16 | unsigned long block, char *buf) | |
17 | { | |
18 | size_t retlen; | |
19 | ||
329ad399 | 20 | if (mtd_read(dev->mtd, (block * 512), 512, &retlen, buf)) |
1da177e4 LT |
21 | return 1; |
22 | return 0; | |
23 | } | |
24 | ||
25 | static int mtdblock_writesect(struct mtd_blktrans_dev *dev, | |
26 | unsigned long block, char *buf) | |
27 | { | |
28 | size_t retlen; | |
29 | ||
eda95cbf | 30 | if (mtd_write(dev->mtd, (block * 512), 512, &retlen, buf)) |
1da177e4 LT |
31 | return 1; |
32 | return 0; | |
33 | } | |
34 | ||
35 | static void mtdblock_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) | |
36 | { | |
95b93a0c | 37 | struct mtd_blktrans_dev *dev = kzalloc(sizeof(*dev), GFP_KERNEL); |
1da177e4 LT |
38 | |
39 | if (!dev) | |
40 | return; | |
41 | ||
1da177e4 LT |
42 | dev->mtd = mtd; |
43 | dev->devnum = mtd->index; | |
19187672 | 44 | |
1da177e4 LT |
45 | dev->size = mtd->size >> 9; |
46 | dev->tr = tr; | |
af63a3bc | 47 | dev->readonly = 1; |
1da177e4 | 48 | |
298304f1 ML |
49 | if (add_mtd_blktrans_dev(dev)) |
50 | kfree(dev); | |
1da177e4 LT |
51 | } |
52 | ||
53 | static void mtdblock_remove_dev(struct mtd_blktrans_dev *dev) | |
54 | { | |
55 | del_mtd_blktrans_dev(dev); | |
1da177e4 LT |
56 | } |
57 | ||
58 | static struct mtd_blktrans_ops mtdblock_tr = { | |
59 | .name = "mtdblock", | |
2aabeb20 | 60 | .major = MTD_BLOCK_MAJOR, |
1da177e4 | 61 | .part_bits = 0, |
19187672 | 62 | .blksize = 512, |
1da177e4 LT |
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 | ||
70 | static int __init mtdblock_init(void) | |
71 | { | |
72 | return register_mtd_blktrans(&mtdblock_tr); | |
73 | } | |
74 | ||
75 | static void __exit mtdblock_exit(void) | |
76 | { | |
77 | deregister_mtd_blktrans(&mtdblock_tr); | |
78 | } | |
79 | ||
80 | module_init(mtdblock_init); | |
81 | module_exit(mtdblock_exit); | |
82 | ||
83 | MODULE_LICENSE("GPL"); | |
84 | MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>"); | |
85 | MODULE_DESCRIPTION("Simple read-only block device emulation access to MTD devices"); |