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/*
* YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
*
* Copyright (C) 2002-2010 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 Y_INLINE __u8 *yaffs_BlockBits(yaffs_Device *dev, int blk)
{
if (blk < dev->internalStartBlock || blk > dev->internalEndBlock) {
T(YAFFS_TRACE_ERROR,
(TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),
blk));
YBUG();
}
return dev->chunkBits +
(dev->chunkBitmapStride * (blk - dev->internalStartBlock));
}
void yaffs_VerifyChunkBitId(yaffs_Device *dev, int blk, int chunk)
{
if (blk < dev->internalStartBlock || blk > dev->internalEndBlock ||
chunk < 0 || chunk >= dev->param.nChunksPerBlock) {
T(YAFFS_TRACE_ERROR,
(TSTR("**>> yaffs: Chunk Id (%d:%d) invalid"TENDSTR),
blk, chunk));
YBUG();
}
}
void yaffs_ClearChunkBits(yaffs_Device *dev, int blk)
{
__u8 *blkBits = yaffs_BlockBits(dev, blk);
memset(blkBits, 0, dev->chunkBitmapStride);
}
void yaffs_ClearChunkBit(yaffs_Device *dev, int blk, int chunk)
{
__u8 *blkBits = yaffs_BlockBits(dev, blk);
yaffs_VerifyChunkBitId(dev, blk, chunk);
blkBits[chunk / 8] &= ~(1 << (chunk & 7));
}
void yaffs_SetChunkBit(yaffs_Device *dev, int blk, int chunk)
{
__u8 *blkBits = yaffs_BlockBits(dev, blk);
yaffs_VerifyChunkBitId(dev, blk, chunk);
blkBits[chunk / 8] |= (1 << (chunk & 7));
}
int yaffs_CheckChunkBit(yaffs_Device *dev, int blk, int chunk)
{
__u8 *blkBits = yaffs_BlockBits(dev, blk);
yaffs_VerifyChunkBitId(dev, blk, chunk);
return (blkBits[chunk / 8] & (1 << (chunk & 7))) ? 1 : 0;
}
int yaffs_StillSomeChunkBits(yaffs_Device *dev, int blk)
{
__u8 *blkBits = yaffs_BlockBits(dev, blk);
int i;
for (i = 0; i < dev->chunkBitmapStride; i++) {
if (*blkBits)
return 1;
blkBits++;
}
return 0;
}
int yaffs_CountChunkBits(yaffs_Device *dev, int blk)
{
__u8 *blkBits = yaffs_BlockBits(dev, blk);
int i;
int n = 0;
for (i = 0; i < dev->chunkBitmapStride; i++) {
__u8 x = *blkBits;
while (x) {
if (x & 1)
n++;
x >>= 1;
}
blkBits++;
}
return n;
}
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