mirror of https://github.com/hak5/openwrt-owl.git
106 lines
2.4 KiB
C
106 lines
2.4 KiB
C
|
/*
|
||
|
|
* 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_dev_t *dev, int blk)
|
||
|
|
{
|
||
|
|
if (blk < dev->internal_start_block || blk > dev->internal_end_block) {
|
||
|
|
T(YAFFS_TRACE_ERROR,
|
||
|
|
(TSTR("**>> yaffs: BlockBits block %d is not valid" TENDSTR),
|
||
|
|
blk));
|
||
|
|
YBUG();
|
||
|
|
}
|
||
|
|
return dev->chunk_bits +
|
||
|
|
(dev->chunk_bit_stride * (blk - dev->internal_start_block));
|
||
|
|
}
|
||
|
|
|
||
|
|
void yaffs_verify_chunk_bit_id(yaffs_dev_t *dev, int blk, int chunk)
|
||
|
|
{
|
||
|
|
if (blk < dev->internal_start_block || blk > dev->internal_end_block ||
|
||
|
|
chunk < 0 || chunk >= dev->param.chunks_per_block) {
|
||
|
|
T(YAFFS_TRACE_ERROR,
|
||
|
|
(TSTR("**>> yaffs: Chunk Id (%d:%d) invalid"TENDSTR),
|
||
|
|
blk, chunk));
|
||
|
|
YBUG();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void yaffs_clear_chunk_bits(yaffs_dev_t *dev, int blk)
|
||
|
|
{
|
||
|
|
__u8 *blkBits = yaffs_BlockBits(dev, blk);
|
||
|
|
|
||
|
|
memset(blkBits, 0, dev->chunk_bit_stride);
|
||
|
|
}
|
||
|
|
|
||
|
|
void yaffs_clear_chunk_bit(yaffs_dev_t *dev, int blk, int chunk)
|
||
|
|
{
|
||
|
|
__u8 *blkBits = yaffs_BlockBits(dev, blk);
|
||
|
|
|
||
|
|
yaffs_verify_chunk_bit_id(dev, blk, chunk);
|
||
|
|
|
||
|
|
blkBits[chunk / 8] &= ~(1 << (chunk & 7));
|
||
|
|
}
|
||
|
|
|
||
|
|
void yaffs_set_chunk_bit(yaffs_dev_t *dev, int blk, int chunk)
|
||
|
|
{
|
||
|
|
__u8 *blkBits = yaffs_BlockBits(dev, blk);
|
||
|
|
|
||
|
|
yaffs_verify_chunk_bit_id(dev, blk, chunk);
|
||
|
|
|
||
|
|
blkBits[chunk / 8] |= (1 << (chunk & 7));
|
||
|
|
}
|
||
|
|
|
||
|
|
int yaffs_check_chunk_bit(yaffs_dev_t *dev, int blk, int chunk)
|
||
|
|
{
|
||
|
|
__u8 *blkBits = yaffs_BlockBits(dev, blk);
|
||
|
|
yaffs_verify_chunk_bit_id(dev, blk, chunk);
|
||
|
|
|
||
|
|
return (blkBits[chunk / 8] & (1 << (chunk & 7))) ? 1 : 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
int yaffs_still_some_chunks(yaffs_dev_t *dev, int blk)
|
||
|
|
{
|
||
|
|
__u8 *blkBits = yaffs_BlockBits(dev, blk);
|
||
|
|
int i;
|
||
|
|
for (i = 0; i < dev->chunk_bit_stride; i++) {
|
||
|
|
if (*blkBits)
|
||
|
|
return 1;
|
||
|
|
blkBits++;
|
||
|
|
}
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
int yaffs_count_chunk_bits(yaffs_dev_t *dev, int blk)
|
||
|
|
{
|
||
|
|
__u8 *blkBits = yaffs_BlockBits(dev, blk);
|
||
|
|
int i;
|
||
|
|
int n = 0;
|
||
|
|
for (i = 0; i < dev->chunk_bit_stride; i++) {
|
||
|
|
__u8 x = *blkBits;
|
||
|
|
while (x) {
|
||
|
|
if (x & 1)
|
||
|
|
n++;
|
||
|
|
x >>= 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
blkBits++;
|
||
|
|
}
|
||
|
|
return n;
|
||
|
|
}
|
||
|
|
|