blob: ae329e8b4acbfd66147a3ff1761632f64484e52a (
plain)
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
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
|
/*
* These are too big to be inlined.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/bitops.h>
#include <asm/byteorder.h>
unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
unsigned long offset)
{
const unsigned long *p = addr + (offset >> 6);
unsigned long result = offset & ~63UL;
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= 63UL;
if (offset) {
tmp = *(p++);
tmp |= ~0UL >> (64 - offset);
if (size < 64)
goto found_first;
if (~tmp)
goto found_middle;
size -= 64;
result += 64;
}
while (size & ~63UL) {
if (~(tmp = *(p++)))
goto found_middle;
result += 64;
size -= 64;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp |= ~0UL << size;
if (tmp == ~0UL) /* Are any bits zero? */
return result + size; /* Nope. */
found_middle:
return result + ffz(tmp);
}
EXPORT_SYMBOL(find_next_zero_bit);
unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
unsigned long offset)
{
const unsigned long *p = addr + (offset >> 6);
unsigned long result = offset & ~63UL;
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= 63UL;
if (offset) {
tmp = *(p++);
tmp &= (~0UL << offset);
if (size < 64)
goto found_first;
if (tmp)
goto found_middle;
size -= 64;
result += 64;
}
while (size & ~63UL) {
if ((tmp = *(p++)))
goto found_middle;
result += 64;
size -= 64;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp &= (~0UL >> (64 - size));
if (tmp == 0UL) /* Are any bits set? */
return result + size; /* Nope. */
found_middle:
return result + __ffs(tmp);
}
EXPORT_SYMBOL(find_next_bit);
static inline unsigned int ext2_ilog2(unsigned int x)
{
int lz;
asm("cntlzw %0,%1": "=r"(lz):"r"(x));
return 31 - lz;
}
static inline unsigned int ext2_ffz(unsigned int x)
{
u32 rc;
if ((x = ~x) == 0)
return 32;
rc = ext2_ilog2(x & -x);
return rc;
}
unsigned long find_next_zero_le_bit(const unsigned long *addr, unsigned long size,
unsigned long offset)
{
const unsigned int *p = ((const unsigned int *)addr) + (offset >> 5);
unsigned int result = offset & ~31;
unsigned int tmp;
if (offset >= size)
return size;
size -= result;
offset &= 31;
if (offset) {
tmp = cpu_to_le32p(p++);
tmp |= ~0U >> (32 - offset); /* bug or feature ? */
if (size < 32)
goto found_first;
if (tmp != ~0)
goto found_middle;
size -= 32;
result += 32;
}
while (size >= 32) {
if ((tmp = cpu_to_le32p(p++)) != ~0)
goto found_middle;
result += 32;
size -= 32;
}
if (!size)
return result;
tmp = cpu_to_le32p(p);
found_first:
tmp |= ~0 << size;
if (tmp == ~0) /* Are any bits zero? */
return result + size; /* Nope. */
found_middle:
return result + ext2_ffz(tmp);
}
EXPORT_SYMBOL(find_next_zero_le_bit);
|
