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
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
|
/* $Id: bitops.h,v 1.3 2000/10/17 14:56:27 bjornw Exp $ */
/* all of these should probably be rewritten in assembler for speed. */
#ifndef _CRIS_BITOPS_H
#define _CRIS_BITOPS_H
#include <asm/system.h>
/*
* These have to be done with inline assembly: that way the bit-setting
* is guaranteed to be atomic. All bit operations return 0 if the bit
* was cleared before the operation and != 0 if it was not.
*
* bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
*/
/*
* Some hacks to defeat gcc over-optimizations..
*/
struct __dummy { unsigned long a[100]; };
#define ADDR (*(struct __dummy *) addr)
#define CONST_ADDR (*(const struct __dummy *) addr)
#define set_bit(nr, addr) (void)test_and_set_bit(nr, addr)
#define clear_bit(nr, addr) (void)test_and_clear_bit(nr, addr)
#define change_bit(nr, addr) (void)test_and_change_bit(nr, addr)
extern __inline__ int test_and_set_bit(int nr, void *addr)
{
unsigned int mask, retval;
unsigned long flags;
unsigned int *adr = (unsigned int *)addr;
adr += nr >> 5;
mask = 1 << (nr & 0x1f);
save_flags(flags);
cli();
retval = (mask & *adr) != 0;
*adr |= mask;
restore_flags(flags);
return retval;
}
/*
* clear_bit() doesn't provide any barrier for the compiler.
*/
#define smp_mb__before_clear_bit() barrier()
#define smp_mb__after_clear_bit() barrier()
extern __inline__ int test_and_clear_bit(int nr, void *addr)
{
unsigned int mask, retval;
unsigned long flags;
unsigned int *adr = (unsigned int *)addr;
adr += nr >> 5;
mask = 1 << (nr & 0x1f);
save_flags(flags);
cli();
retval = (mask & *adr) != 0;
*adr &= ~mask;
restore_flags(flags);
return retval;
}
extern __inline__ int test_and_change_bit(int nr, void *addr)
{
unsigned int mask, retval;
unsigned long flags;
unsigned int *adr = (unsigned int *)addr;
adr += nr >> 5;
mask = 1 << (nr & 0x1f);
save_flags(flags);
cli();
retval = (mask & *adr) != 0;
*adr ^= mask;
restore_flags(flags);
return retval;
}
/*
* This routine doesn't need to be atomic.
*/
extern __inline__ int test_bit(int nr, const void *addr)
{
unsigned int mask;
unsigned int *adr = (unsigned int *)addr;
adr += nr >> 5;
mask = 1 << (nr & 0x1f);
return ((mask & *adr) != 0);
}
/*
* Find-bit routines..
*/
/*
* ffz = Find First Zero in word. Undefined if no zero exists,
* so code should check against ~0UL first..
*/
extern __inline__ unsigned long ffz(unsigned long word)
{
unsigned long result = 0;
while(word & 1) {
result++;
word >>= 1;
}
return result;
}
/*
* Find first one in word. Undefined if no one exists,
* so code should check against 0UL first..
*/
extern __inline__ unsigned long find_first_one(unsigned long word)
{
unsigned long result = 0;
while(!(word & 1)) {
result++;
word >>= 1;
}
return result;
}
extern __inline__ int find_next_zero_bit (void * addr, int size, int offset)
{
unsigned long *p = ((unsigned long *) addr) + (offset >> 5);
unsigned long result = offset & ~31UL;
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= 31UL;
if (offset) {
tmp = *(p++);
tmp |= ~0UL >> (32-offset);
if (size < 32)
goto found_first;
if (~tmp)
goto found_middle;
size -= 32;
result += 32;
}
while (size & ~31UL) {
if (~(tmp = *(p++)))
goto found_middle;
result += 32;
size -= 32;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp |= ~0UL >> size;
found_middle:
return result + ffz(tmp);
}
#define find_first_zero_bit(addr, size) \
find_next_zero_bit((addr), (size), 0)
#ifdef __KERNEL__
#define ext2_set_bit test_and_set_bit
#define ext2_clear_bit test_and_clear_bit
#define ext2_test_bit test_bit
#define ext2_find_first_zero_bit find_first_zero_bit
#define ext2_find_next_zero_bit find_next_zero_bit
/* Bitmap functions for the minix filesystem. */
#define minix_set_bit(nr,addr) test_and_set_bit(nr,addr)
#define minix_clear_bit(nr,addr) test_and_clear_bit(nr,addr)
#define minix_test_bit(nr,addr) test_bit(nr,addr)
#define minix_find_first_zero_bit(addr,size) find_first_zero_bit(addr,size)
#endif /* __KERNEL__ */
#endif /* _CRIS_BITOPS_H */
|
