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106 lines
2.4 KiB
C
106 lines
2.4 KiB
C
/*
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* YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
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*
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* Copyright (C) 2002-2010 Aleph One Ltd.
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* for Toby Churchill Ltd and Brightstar Engineering
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*
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* Created by Charles Manning <charles@aleph1.co.uk>
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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 version 2 as
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* published by the Free Software Foundation.
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*/
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#include "yaffs_bitmap.h"
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#include "yaffs_trace.h"
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/*
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* Chunk bitmap manipulations
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*/
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static Y_INLINE __u8 *yaffs_BlockBits(yaffs_dev_t *dev, int blk)
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{
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if (blk < dev->internal_start_block || blk > dev->internal_end_block) {
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T(YAFFS_TRACE_ERROR,
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(TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),
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blk));
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YBUG();
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}
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return dev->chunk_bits +
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(dev->chunk_bit_stride * (blk - dev->internal_start_block));
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}
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void yaffs_verify_chunk_bit_id(yaffs_dev_t *dev, int blk, int chunk)
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{
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if (blk < dev->internal_start_block || blk > dev->internal_end_block ||
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chunk < 0 || chunk >= dev->param.chunks_per_block) {
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T(YAFFS_TRACE_ERROR,
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(TSTR("**>> yaffs: Chunk Id (%d:%d) invalid"TENDSTR),
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blk, chunk));
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YBUG();
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}
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}
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void yaffs_clear_chunk_bits(yaffs_dev_t *dev, int blk)
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{
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__u8 *blkBits = yaffs_BlockBits(dev, blk);
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memset(blkBits, 0, dev->chunk_bit_stride);
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}
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void yaffs_clear_chunk_bit(yaffs_dev_t *dev, int blk, int chunk)
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{
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__u8 *blkBits = yaffs_BlockBits(dev, blk);
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yaffs_verify_chunk_bit_id(dev, blk, chunk);
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blkBits[chunk / 8] &= ~(1 << (chunk & 7));
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}
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void yaffs_set_chunk_bit(yaffs_dev_t *dev, int blk, int chunk)
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{
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__u8 *blkBits = yaffs_BlockBits(dev, blk);
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yaffs_verify_chunk_bit_id(dev, blk, chunk);
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blkBits[chunk / 8] |= (1 << (chunk & 7));
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}
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int yaffs_check_chunk_bit(yaffs_dev_t *dev, int blk, int chunk)
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{
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__u8 *blkBits = yaffs_BlockBits(dev, blk);
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yaffs_verify_chunk_bit_id(dev, blk, chunk);
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return (blkBits[chunk / 8] & (1 << (chunk & 7))) ? 1 : 0;
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}
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int yaffs_still_some_chunks(yaffs_dev_t *dev, int blk)
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{
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__u8 *blkBits = yaffs_BlockBits(dev, blk);
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int i;
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for (i = 0; i < dev->chunk_bit_stride; i++) {
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if (*blkBits)
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return 1;
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blkBits++;
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}
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return 0;
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}
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int yaffs_count_chunk_bits(yaffs_dev_t *dev, int blk)
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{
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__u8 *blkBits = yaffs_BlockBits(dev, blk);
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int i;
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int n = 0;
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for (i = 0; i < dev->chunk_bit_stride; i++) {
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__u8 x = *blkBits;
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while (x) {
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if (x & 1)
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n++;
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x >>= 1;
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}
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blkBits++;
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}
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return n;
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}
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