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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
Borislav Petkov4677d4a2010-05-03 14:57:11 +020013extern unsigned int __sw_hweight8(unsigned int w);
14extern unsigned int __sw_hweight16(unsigned int w);
15extern unsigned int __sw_hweight32(unsigned int w);
16extern unsigned long __sw_hweight64(__u64 w);
17
Linus Torvalds1da177e2005-04-16 15:20:36 -070018/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070019 * Include this here because some architectures need generic_ffs/fls in
20 * scope
21 */
22#include <asm/bitops.h>
23
Akinobu Mita984b3f52010-03-05 13:41:37 -080024#define for_each_set_bit(bit, addr, size) \
Shannon Nelson3e037452007-10-16 01:27:40 -070025 for ((bit) = find_first_bit((addr), (size)); \
26 (bit) < (size); \
27 (bit) = find_next_bit((addr), (size), (bit) + 1))
28
Linus Torvalds1da177e2005-04-16 15:20:36 -070029static __inline__ int get_bitmask_order(unsigned int count)
30{
31 int order;
Peter Zijlstra9f416992010-01-22 15:59:29 +010032
Linus Torvalds1da177e2005-04-16 15:20:36 -070033 order = fls(count);
34 return order; /* We could be slightly more clever with -1 here... */
35}
36
Siddha, Suresh B94605ef2005-11-05 17:25:54 +010037static __inline__ int get_count_order(unsigned int count)
38{
39 int order;
Peter Zijlstra9f416992010-01-22 15:59:29 +010040
Siddha, Suresh B94605ef2005-11-05 17:25:54 +010041 order = fls(count) - 1;
42 if (count & (count - 1))
43 order++;
44 return order;
45}
46
Linus Torvalds1da177e2005-04-16 15:20:36 -070047static inline unsigned long hweight_long(unsigned long w)
48{
Akinobu Mitae9bebd62006-03-26 01:39:55 -080049 return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
Linus Torvalds1da177e2005-04-16 15:20:36 -070050}
51
Robert P. J. Day45f8bde2007-01-26 00:57:09 -080052/**
Linus Torvalds1da177e2005-04-16 15:20:36 -070053 * rol32 - rotate a 32-bit value left
Linus Torvalds1da177e2005-04-16 15:20:36 -070054 * @word: value to rotate
55 * @shift: bits to roll
56 */
57static inline __u32 rol32(__u32 word, unsigned int shift)
58{
59 return (word << shift) | (word >> (32 - shift));
60}
61
Robert P. J. Day45f8bde2007-01-26 00:57:09 -080062/**
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 * ror32 - rotate a 32-bit value right
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 * @word: value to rotate
65 * @shift: bits to roll
66 */
67static inline __u32 ror32(__u32 word, unsigned int shift)
68{
69 return (word >> shift) | (word << (32 - shift));
70}
71
Harvey Harrison3afe3922008-03-28 14:16:01 -070072/**
73 * rol16 - rotate a 16-bit value left
74 * @word: value to rotate
75 * @shift: bits to roll
76 */
77static inline __u16 rol16(__u16 word, unsigned int shift)
78{
79 return (word << shift) | (word >> (16 - shift));
80}
81
82/**
83 * ror16 - rotate a 16-bit value right
84 * @word: value to rotate
85 * @shift: bits to roll
86 */
87static inline __u16 ror16(__u16 word, unsigned int shift)
88{
89 return (word >> shift) | (word << (16 - shift));
90}
91
92/**
93 * rol8 - rotate an 8-bit value left
94 * @word: value to rotate
95 * @shift: bits to roll
96 */
97static inline __u8 rol8(__u8 word, unsigned int shift)
98{
99 return (word << shift) | (word >> (8 - shift));
100}
101
102/**
103 * ror8 - rotate an 8-bit value right
104 * @word: value to rotate
105 * @shift: bits to roll
106 */
107static inline __u8 ror8(__u8 word, unsigned int shift)
108{
109 return (word >> shift) | (word << (8 - shift));
110}
111
Andrew Morton962749a2006-03-25 03:08:01 -0800112static inline unsigned fls_long(unsigned long l)
113{
114 if (sizeof(l) == 4)
115 return fls(l);
116 return fls64(l);
117}
118
Steven Whitehouse952043a2009-04-23 08:48:15 +0100119/**
120 * __ffs64 - find first set bit in a 64 bit word
121 * @word: The 64 bit word
122 *
123 * On 64 bit arches this is a synomyn for __ffs
124 * The result is not defined if no bits are set, so check that @word
125 * is non-zero before calling this.
126 */
127static inline unsigned long __ffs64(u64 word)
128{
129#if BITS_PER_LONG == 32
130 if (((u32)word) == 0UL)
131 return __ffs((u32)(word >> 32)) + 32;
132#elif BITS_PER_LONG != 64
133#error BITS_PER_LONG not 32 or 64
134#endif
135 return __ffs((unsigned long)word);
136}
137
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100138#ifdef __KERNEL__
Alexander van Heukelum77b9bd92008-04-01 11:46:19 +0200139#ifdef CONFIG_GENERIC_FIND_FIRST_BIT
Alexander van Heukelum77b9bd92008-04-01 11:46:19 +0200140
141/**
142 * find_first_bit - find the first set bit in a memory region
143 * @addr: The address to start the search at
144 * @size: The maximum size to search
145 *
146 * Returns the bit number of the first set bit.
147 */
Thomas Gleixnerfee4b192008-04-29 12:01:02 +0200148extern unsigned long find_first_bit(const unsigned long *addr,
149 unsigned long size);
Alexander van Heukelum77b9bd92008-04-01 11:46:19 +0200150
151/**
152 * find_first_zero_bit - find the first cleared bit in a memory region
153 * @addr: The address to start the search at
154 * @size: The maximum size to search
155 *
156 * Returns the bit number of the first cleared bit.
157 */
Thomas Gleixnerfee4b192008-04-29 12:01:02 +0200158extern unsigned long find_first_zero_bit(const unsigned long *addr,
159 unsigned long size);
Alexander van Heukelum77b9bd92008-04-01 11:46:19 +0200160#endif /* CONFIG_GENERIC_FIND_FIRST_BIT */
161
Rusty Russellab53d472009-01-01 10:12:19 +1030162#ifdef CONFIG_GENERIC_FIND_LAST_BIT
163/**
164 * find_last_bit - find the last set bit in a memory region
165 * @addr: The address to start the search at
166 * @size: The maximum size to search
167 *
168 * Returns the bit number of the first set bit, or size.
169 */
170extern unsigned long find_last_bit(const unsigned long *addr,
171 unsigned long size);
172#endif /* CONFIG_GENERIC_FIND_LAST_BIT */
173
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100174#ifdef CONFIG_GENERIC_FIND_NEXT_BIT
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100175
176/**
177 * find_next_bit - find the next set bit in a memory region
178 * @addr: The address to base the search on
179 * @offset: The bitnumber to start searching at
180 * @size: The bitmap size in bits
181 */
Thomas Gleixnerfee4b192008-04-29 12:01:02 +0200182extern unsigned long find_next_bit(const unsigned long *addr,
183 unsigned long size, unsigned long offset);
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100184
185/**
186 * find_next_zero_bit - find the next cleared bit in a memory region
187 * @addr: The address to base the search on
188 * @offset: The bitnumber to start searching at
189 * @size: The bitmap size in bits
190 */
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100191
Thomas Gleixnerfee4b192008-04-29 12:01:02 +0200192extern unsigned long find_next_zero_bit(const unsigned long *addr,
193 unsigned long size,
194 unsigned long offset);
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100195
Alexander van Heukelum64970b62008-03-11 16:17:19 +0100196#endif /* CONFIG_GENERIC_FIND_NEXT_BIT */
197#endif /* __KERNEL__ */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198#endif