75 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			75 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-or-later
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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| 	if (!dev)
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| 		return;
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| 
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| 	dev->mtd = mtd;
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| 	dev->devnum = mtd->index;
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| 
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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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| 
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| 	if (add_mtd_blktrans_dev(dev))
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| 		kfree(dev);
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| }
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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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| 
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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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| 
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| module_mtd_blktrans(mtdblock_tr);
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| 
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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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