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/*
* YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
*
* Copyright (C) 2002-2011 Aleph One Ltd.
* for Toby Churchill Ltd and Brightstar Engineering
*
* Created by Charles Manning <charles@aleph1.co.uk>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include "yaffs_bitmap.h"
#include "yaffs_trace.h"
/*
* Chunk bitmap manipulations
*/
static inline u8 *yaffs_block_bits(struct yaffs_dev *dev, int blk)
{
if (blk < dev->internal_start_block || blk > dev->internal_end_block) {
yaffs_trace(YAFFS_TRACE_ERROR,
"BlockBits block %d is not valid",
blk);
BUG();
}
return dev->chunk_bits +
(dev->chunk_bit_stride * (blk - dev->internal_start_block));
}
void yaffs_verify_chunk_bit_id(struct yaffs_dev *dev, int blk, int chunk)
{
if (blk < dev->internal_start_block || blk > dev->internal_end_block ||
chunk < 0 || chunk >= dev->param.chunks_per_block) {
yaffs_trace(YAFFS_TRACE_ERROR,
"Chunk Id (%d:%d) invalid",
blk, chunk);
BUG();
}
}
void yaffs_clear_chunk_bits(struct yaffs_dev *dev, int blk)
{
u8 *blk_bits = yaffs_block_bits(dev, blk);
memset(blk_bits, 0, dev->chunk_bit_stride);
}
void yaffs_clear_chunk_bit(struct yaffs_dev *dev, int blk, int chunk)
{
u8 *blk_bits = yaffs_block_bits(dev, blk);
yaffs_verify_chunk_bit_id(dev, blk, chunk);
blk_bits[chunk / 8] &= ~(1 << (chunk & 7));
}
void yaffs_set_chunk_bit(struct yaffs_dev *dev, int blk, int chunk)
{
u8 *blk_bits = yaffs_block_bits(dev, blk);
yaffs_verify_chunk_bit_id(dev, blk, chunk);
blk_bits[chunk / 8] |= (1 << (chunk & 7));
}
int yaffs_check_chunk_bit(struct yaffs_dev *dev, int blk, int chunk)
{
u8 *blk_bits = yaffs_block_bits(dev, blk);
yaffs_verify_chunk_bit_id(dev, blk, chunk);
return (blk_bits[chunk / 8] & (1 << (chunk & 7))) ? 1 : 0;
}
int yaffs_still_some_chunks(struct yaffs_dev *dev, int blk)
{
u8 *blk_bits = yaffs_block_bits(dev, blk);
int i;
for (i = 0; i < dev->chunk_bit_stride; i++) {
if (*blk_bits)
return 1;
blk_bits++;
}
return 0;
}
int yaffs_count_chunk_bits(struct yaffs_dev *dev, int blk)
{
u8 *blk_bits = yaffs_block_bits(dev, blk);
int i;
int n = 0;
for (i = 0; i < dev->chunk_bit_stride; i++, blk_bits++)
n += hweight8(*blk_bits);
return n;
}
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