1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
|
/*
* 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;
}
|
