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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _LINUX_BITOPS_H
2#define _LINUX_BITOPS_H
3#include <asm/types.h>
4
Jiri Slabyd05be132007-10-18 23:40:31 -07005#ifdef __KERNEL__
Jiri Slaby93043ec2007-10-18 23:40:35 -07006#define BIT(nr) (1UL << (nr))
Jiri Slabyd05be132007-10-18 23:40:31 -07007#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG))
8#define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
Jiri Slabyd05be132007-10-18 23:40:31 -07009#define BITS_PER_BYTE 8
Eric Dumazetede9c692008-04-29 00:58:35 -070010#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
Jiri Slabyd05be132007-10-18 23:40:31 -070011#endif
12
Linus Torvalds1da177e2005-04-16 15:20:36 -070013/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070014 * Include this here because some architectures need generic_ffs/fls in
15 * scope
16 */
17#include <asm/bitops.h>
18
Shannon Nelson3e037452007-10-16 01:27:40 -070019#define for_each_bit(bit, addr, size) \
20 for ((bit) = find_first_bit((addr), (size)); \
21 (bit) < (size); \
22 (bit) = find_next_bit((addr), (size), (bit) + 1))
23
24
Linus Torvalds1da177e2005-04-16 15:20:36 -070025static __inline__ int get_bitmask_order(unsigned int count)
26{
27 int order;
28
29 order = fls(count);
30 return order; /* We could be slightly more clever with -1 here... */
31}
32
Siddha, Suresh B94605ef2005-11-05 17:25:54 +010033static __inline__ int get_count_order(unsigned int count)
34{
35 int order;
36
37 order = fls(count) - 1;
38 if (count & (count - 1))
39 order++;
40 return order;
41}
42
Linus Torvalds1da177e2005-04-16 15:20:36 -070043static inline unsigned long hweight_long(unsigned long w)
44{
Akinobu Mitae9bebd62006-03-26 01:39:55 -080045 return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
Linus Torvalds1da177e2005-04-16 15:20:36 -070046}
47
Robert P. J. Day45f8bde2007-01-26 00:57:09 -080048/**
Linus Torvalds1da177e2005-04-16 15:20:36 -070049 * rol32 - rotate a 32-bit value left
Linus Torvalds1da177e2005-04-16 15:20:36 -070050 * @word: value to rotate
51 * @shift: bits to roll
52 */
53static inline __u32 rol32(__u32 word, unsigned int shift)
54{
55 return (word << shift) | (word >> (32 - shift));
56}
57
Robert P. J. Day45f8bde2007-01-26 00:57:09 -080058/**
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 * ror32 - rotate a 32-bit value right
Linus Torvalds1da177e2005-04-16 15:20:36 -070060 * @word: value to rotate
61 * @shift: bits to roll
62 */
63static inline __u32 ror32(__u32 word, unsigned int shift)
64{
65 return (word >> shift) | (word << (32 - shift));
66}
67
Harvey Harrison3afe3922008-03-28 14:16:01 -070068/**
69 * rol16 - rotate a 16-bit value left
70 * @word: value to rotate
71 * @shift: bits to roll
72 */
73static inline __u16 rol16(__u16 word, unsigned int shift)
74{
75 return (word << shift) | (word >> (16 - shift));
76}
77
78/**
79 * ror16 - rotate a 16-bit value right
80 * @word: value to rotate
81 * @shift: bits to roll
82 */
83static inline __u16 ror16(__u16 word, unsigned int shift)
84{
85 return (word >> shift) | (word << (16 - shift));
86}
87
88/**
89 * rol8 - rotate an 8-bit value left
90 * @word: value to rotate
91 * @shift: bits to roll
92 */
93static inline __u8 rol8(__u8 word, unsigned int shift)
94{
95 return (word << shift) | (word >> (8 - shift));
96}
97
98/**
99 * ror8 - rotate an 8-bit value right
100 * @word: value to rotate
101 * @shift: bits to roll
102 */
103static inline __u8 ror8(__u8 word, unsigned int shift)
104{
105 return (word >> shift) | (word << (8 - shift));
106}
107
Andrew Morton962749a2006-03-25 03:08:01 -0800108static inline unsigned fls_long(unsigned long l)
109{
110 if (sizeof(l) == 4)
111 return fls(l);
112 return fls64(l);
113}
114
Steven Whitehouse952043a2009-04-23 08:48:15 +0100115/**
116 * __ffs64 - find first set bit in a 64 bit word
117 * @word: The 64 bit word
118 *
119 * On 64 bit arches this is a synomyn for __ffs
120 * The result is not defined if no bits are set, so check that @word
121 * is non-zero before calling this.
122 */
123static inline unsigned long __ffs64(u64 word)
124{
125#if BITS_PER_LONG == 32
126 if (((u32)word) == 0UL)
127 return __ffs((u32)(word >> 32)) + 32;
128#elif BITS_PER_LONG != 64
129#error BITS_PER_LONG not 32 or 64
130#endif
131 return __ffs((unsigned long)word);
132}
133
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100134#ifdef __KERNEL__
Alexander van Heukelum77b9bd92008-04-01 11:46:19 +0200135#ifdef CONFIG_GENERIC_FIND_FIRST_BIT
Alexander van Heukelum77b9bd92008-04-01 11:46:19 +0200136
137/**
138 * find_first_bit - find the first set bit in a memory region
139 * @addr: The address to start the search at
140 * @size: The maximum size to search
141 *
142 * Returns the bit number of the first set bit.
143 */
Thomas Gleixnerfee4b192008-04-29 12:01:02 +0200144extern unsigned long find_first_bit(const unsigned long *addr,
145 unsigned long size);
Alexander van Heukelum77b9bd92008-04-01 11:46:19 +0200146
147/**
148 * find_first_zero_bit - find the first cleared bit in a memory region
149 * @addr: The address to start the search at
150 * @size: The maximum size to search
151 *
152 * Returns the bit number of the first cleared bit.
153 */
Thomas Gleixnerfee4b192008-04-29 12:01:02 +0200154extern unsigned long find_first_zero_bit(const unsigned long *addr,
155 unsigned long size);
Alexander van Heukelum77b9bd92008-04-01 11:46:19 +0200156#endif /* CONFIG_GENERIC_FIND_FIRST_BIT */
157
Rusty Russellab53d472009-01-01 10:12:19 +1030158#ifdef CONFIG_GENERIC_FIND_LAST_BIT
159/**
160 * find_last_bit - find the last set bit in a memory region
161 * @addr: The address to start the search at
162 * @size: The maximum size to search
163 *
164 * Returns the bit number of the first set bit, or size.
165 */
166extern unsigned long find_last_bit(const unsigned long *addr,
167 unsigned long size);
168#endif /* CONFIG_GENERIC_FIND_LAST_BIT */
169
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100170#ifdef CONFIG_GENERIC_FIND_NEXT_BIT
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100171
172/**
173 * find_next_bit - find the next set bit in a memory region
174 * @addr: The address to base the search on
175 * @offset: The bitnumber to start searching at
176 * @size: The bitmap size in bits
177 */
Thomas Gleixnerfee4b192008-04-29 12:01:02 +0200178extern unsigned long find_next_bit(const unsigned long *addr,
179 unsigned long size, unsigned long offset);
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100180
181/**
182 * find_next_zero_bit - find the next cleared bit in a memory region
183 * @addr: The address to base the search on
184 * @offset: The bitnumber to start searching at
185 * @size: The bitmap size in bits
186 */
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100187
Thomas Gleixnerfee4b192008-04-29 12:01:02 +0200188extern unsigned long find_next_zero_bit(const unsigned long *addr,
189 unsigned long size,
190 unsigned long offset);
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100191
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100192#endif /* CONFIG_GENERIC_FIND_NEXT_BIT */
193#endif /* __KERNEL__ */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194#endif