100 lines
2.5 KiB
C
100 lines
2.5 KiB
C
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/*
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* Simple read-only (writable only for RAM) mtdblock driver
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*
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* Copyright © 2001-2010 David Woodhouse <dwmw2@infradead.org>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*
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*/
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#include <linux/init.h>
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#include <linux/slab.h>
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#include <linux/mtd/mtd.h>
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#include <linux/mtd/blktrans.h>
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#include <linux/module.h>
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#include <linux/major.h>
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static int mtdblock_readsect(struct mtd_blktrans_dev *dev,
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unsigned long block, char *buf)
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{
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size_t retlen;
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if (mtd_read(dev->mtd, (block * 512), 512, &retlen, buf))
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return 1;
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return 0;
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}
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static int mtdblock_writesect(struct mtd_blktrans_dev *dev,
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unsigned long block, char *buf)
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{
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size_t retlen;
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if (mtd_write(dev->mtd, (block * 512), 512, &retlen, buf))
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return 1;
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return 0;
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}
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static void mtdblock_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
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{
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struct mtd_blktrans_dev *dev = kzalloc(sizeof(*dev), GFP_KERNEL);
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if (!dev)
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return;
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dev->mtd = mtd;
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dev->devnum = mtd->index;
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dev->size = mtd->size >> 9;
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dev->tr = tr;
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dev->readonly = 1;
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if (add_mtd_blktrans_dev(dev))
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kfree(dev);
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}
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static void mtdblock_remove_dev(struct mtd_blktrans_dev *dev)
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{
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del_mtd_blktrans_dev(dev);
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}
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static struct mtd_blktrans_ops mtdblock_tr = {
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.name = "mtdblock",
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.major = MTD_BLOCK_MAJOR,
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.part_bits = 0,
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.blksize = 512,
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.readsect = mtdblock_readsect,
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.writesect = mtdblock_writesect,
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.add_mtd = mtdblock_add_mtd,
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.remove_dev = mtdblock_remove_dev,
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.owner = THIS_MODULE,
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};
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static int __init mtdblock_init(void)
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{
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return register_mtd_blktrans(&mtdblock_tr);
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}
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static void __exit mtdblock_exit(void)
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{
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deregister_mtd_blktrans(&mtdblock_tr);
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}
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module_init(mtdblock_init);
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module_exit(mtdblock_exit);
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
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MODULE_DESCRIPTION("Simple read-only block device emulation access to MTD devices");
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