| /* |
| * 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> |
| #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"); |