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Linux kernel mirror (for testing)
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1/* $Id: bitops.h,v 1.39 2002/01/30 01:40:00 davem Exp $
2 * bitops.h: Bit string operations on the V9.
3 *
4 * Copyright 1996, 1997 David S. Miller (davem@caip.rutgers.edu)
5 */
6
7#ifndef _SPARC64_BITOPS_H
8#define _SPARC64_BITOPS_H
9
10#include <linux/config.h>
11#include <linux/compiler.h>
12#include <asm/byteorder.h>
13
14extern int test_and_set_bit(unsigned long nr, volatile unsigned long *addr);
15extern int test_and_clear_bit(unsigned long nr, volatile unsigned long *addr);
16extern int test_and_change_bit(unsigned long nr, volatile unsigned long *addr);
17extern void set_bit(unsigned long nr, volatile unsigned long *addr);
18extern void clear_bit(unsigned long nr, volatile unsigned long *addr);
19extern void change_bit(unsigned long nr, volatile unsigned long *addr);
20
21/* "non-atomic" versions... */
22
23static inline void __set_bit(int nr, volatile unsigned long *addr)
24{
25 unsigned long *m = ((unsigned long *)addr) + (nr >> 6);
26
27 *m |= (1UL << (nr & 63));
28}
29
30static inline void __clear_bit(int nr, volatile unsigned long *addr)
31{
32 unsigned long *m = ((unsigned long *)addr) + (nr >> 6);
33
34 *m &= ~(1UL << (nr & 63));
35}
36
37static inline void __change_bit(int nr, volatile unsigned long *addr)
38{
39 unsigned long *m = ((unsigned long *)addr) + (nr >> 6);
40
41 *m ^= (1UL << (nr & 63));
42}
43
44static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
45{
46 unsigned long *m = ((unsigned long *)addr) + (nr >> 6);
47 unsigned long old = *m;
48 unsigned long mask = (1UL << (nr & 63));
49
50 *m = (old | mask);
51 return ((old & mask) != 0);
52}
53
54static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
55{
56 unsigned long *m = ((unsigned long *)addr) + (nr >> 6);
57 unsigned long old = *m;
58 unsigned long mask = (1UL << (nr & 63));
59
60 *m = (old & ~mask);
61 return ((old & mask) != 0);
62}
63
64static inline int __test_and_change_bit(int nr, volatile unsigned long *addr)
65{
66 unsigned long *m = ((unsigned long *)addr) + (nr >> 6);
67 unsigned long old = *m;
68 unsigned long mask = (1UL << (nr & 63));
69
70 *m = (old ^ mask);
71 return ((old & mask) != 0);
72}
73
74#ifdef CONFIG_SMP
75#define smp_mb__before_clear_bit() membar_storeload_loadload()
76#define smp_mb__after_clear_bit() membar_storeload_storestore()
77#else
78#define smp_mb__before_clear_bit() barrier()
79#define smp_mb__after_clear_bit() barrier()
80#endif
81
82static inline int test_bit(int nr, __const__ volatile unsigned long *addr)
83{
84 return (1UL & (addr[nr >> 6] >> (nr & 63))) != 0UL;
85}
86
87/* The easy/cheese version for now. */
88static inline unsigned long ffz(unsigned long word)
89{
90 unsigned long result;
91
92 result = 0;
93 while(word & 1) {
94 result++;
95 word >>= 1;
96 }
97 return result;
98}
99
100/**
101 * __ffs - find first bit in word.
102 * @word: The word to search
103 *
104 * Undefined if no bit exists, so code should check against 0 first.
105 */
106static inline unsigned long __ffs(unsigned long word)
107{
108 unsigned long result = 0;
109
110 while (!(word & 1UL)) {
111 result++;
112 word >>= 1;
113 }
114 return result;
115}
116
117/*
118 * fls: find last bit set.
119 */
120
121#define fls(x) generic_fls(x)
122#define fls64(x) generic_fls64(x)
123
124#ifdef __KERNEL__
125
126/*
127 * Every architecture must define this function. It's the fastest
128 * way of searching a 140-bit bitmap where the first 100 bits are
129 * unlikely to be set. It's guaranteed that at least one of the 140
130 * bits is cleared.
131 */
132static inline int sched_find_first_bit(unsigned long *b)
133{
134 if (unlikely(b[0]))
135 return __ffs(b[0]);
136 if (unlikely(((unsigned int)b[1])))
137 return __ffs(b[1]) + 64;
138 if (b[1] >> 32)
139 return __ffs(b[1] >> 32) + 96;
140 return __ffs(b[2]) + 128;
141}
142
143/*
144 * ffs: find first bit set. This is defined the same way as
145 * the libc and compiler builtin ffs routines, therefore
146 * differs in spirit from the above ffz (man ffs).
147 */
148static inline int ffs(int x)
149{
150 if (!x)
151 return 0;
152 return __ffs((unsigned long)x) + 1;
153}
154
155/*
156 * hweightN: returns the hamming weight (i.e. the number
157 * of bits set) of a N-bit word
158 */
159
160#ifdef ULTRA_HAS_POPULATION_COUNT
161
162static inline unsigned int hweight64(unsigned long w)
163{
164 unsigned int res;
165
166 __asm__ ("popc %1,%0" : "=r" (res) : "r" (w));
167 return res;
168}
169
170static inline unsigned int hweight32(unsigned int w)
171{
172 unsigned int res;
173
174 __asm__ ("popc %1,%0" : "=r" (res) : "r" (w & 0xffffffff));
175 return res;
176}
177
178static inline unsigned int hweight16(unsigned int w)
179{
180 unsigned int res;
181
182 __asm__ ("popc %1,%0" : "=r" (res) : "r" (w & 0xffff));
183 return res;
184}
185
186static inline unsigned int hweight8(unsigned int w)
187{
188 unsigned int res;
189
190 __asm__ ("popc %1,%0" : "=r" (res) : "r" (w & 0xff));
191 return res;
192}
193
194#else
195
196#define hweight64(x) generic_hweight64(x)
197#define hweight32(x) generic_hweight32(x)
198#define hweight16(x) generic_hweight16(x)
199#define hweight8(x) generic_hweight8(x)
200
201#endif
202#endif /* __KERNEL__ */
203
204/**
205 * find_next_bit - find the next set bit in a memory region
206 * @addr: The address to base the search on
207 * @offset: The bitnumber to start searching at
208 * @size: The maximum size to search
209 */
210extern unsigned long find_next_bit(const unsigned long *, unsigned long,
211 unsigned long);
212
213/**
214 * find_first_bit - find the first set bit in a memory region
215 * @addr: The address to start the search at
216 * @size: The maximum size to search
217 *
218 * Returns the bit-number of the first set bit, not the number of the byte
219 * containing a bit.
220 */
221#define find_first_bit(addr, size) \
222 find_next_bit((addr), (size), 0)
223
224/* find_next_zero_bit() finds the first zero bit in a bit string of length
225 * 'size' bits, starting the search at bit 'offset'. This is largely based
226 * on Linus's ALPHA routines, which are pretty portable BTW.
227 */
228
229extern unsigned long find_next_zero_bit(const unsigned long *,
230 unsigned long, unsigned long);
231
232#define find_first_zero_bit(addr, size) \
233 find_next_zero_bit((addr), (size), 0)
234
235#define test_and_set_le_bit(nr,addr) \
236 test_and_set_bit((nr) ^ 0x38, (addr))
237#define test_and_clear_le_bit(nr,addr) \
238 test_and_clear_bit((nr) ^ 0x38, (addr))
239
240static inline int test_le_bit(int nr, __const__ unsigned long * addr)
241{
242 int mask;
243 __const__ unsigned char *ADDR = (__const__ unsigned char *) addr;
244
245 ADDR += nr >> 3;
246 mask = 1 << (nr & 0x07);
247 return ((mask & *ADDR) != 0);
248}
249
250#define find_first_zero_le_bit(addr, size) \
251 find_next_zero_le_bit((addr), (size), 0)
252
253extern unsigned long find_next_zero_le_bit(unsigned long *, unsigned long, unsigned long);
254
255#ifdef __KERNEL__
256
257#define __set_le_bit(nr, addr) \
258 __set_bit((nr) ^ 0x38, (addr))
259#define __clear_le_bit(nr, addr) \
260 __clear_bit((nr) ^ 0x38, (addr))
261#define __test_and_clear_le_bit(nr, addr) \
262 __test_and_clear_bit((nr) ^ 0x38, (addr))
263#define __test_and_set_le_bit(nr, addr) \
264 __test_and_set_bit((nr) ^ 0x38, (addr))
265
266#define ext2_set_bit(nr,addr) \
267 __test_and_set_le_bit((nr),(unsigned long *)(addr))
268#define ext2_set_bit_atomic(lock,nr,addr) \
269 test_and_set_le_bit((nr),(unsigned long *)(addr))
270#define ext2_clear_bit(nr,addr) \
271 __test_and_clear_le_bit((nr),(unsigned long *)(addr))
272#define ext2_clear_bit_atomic(lock,nr,addr) \
273 test_and_clear_le_bit((nr),(unsigned long *)(addr))
274#define ext2_test_bit(nr,addr) \
275 test_le_bit((nr),(unsigned long *)(addr))
276#define ext2_find_first_zero_bit(addr, size) \
277 find_first_zero_le_bit((unsigned long *)(addr), (size))
278#define ext2_find_next_zero_bit(addr, size, off) \
279 find_next_zero_le_bit((unsigned long *)(addr), (size), (off))
280
281/* Bitmap functions for the minix filesystem. */
282#define minix_test_and_set_bit(nr,addr) \
283 test_and_set_bit((nr),(unsigned long *)(addr))
284#define minix_set_bit(nr,addr) \
285 set_bit((nr),(unsigned long *)(addr))
286#define minix_test_and_clear_bit(nr,addr) \
287 test_and_clear_bit((nr),(unsigned long *)(addr))
288#define minix_test_bit(nr,addr) \
289 test_bit((nr),(unsigned long *)(addr))
290#define minix_find_first_zero_bit(addr,size) \
291 find_first_zero_bit((unsigned long *)(addr),(size))
292
293#endif /* __KERNEL__ */
294
295#endif /* defined(_SPARC64_BITOPS_H) */