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36 * libcfs/include/libcfs/user-bitops.h
38 * Author: Nikita Danilov <nikita@clusterfs.com>
41 #ifndef __LIBCFS_USER_BITOPS_H__
42 #define __LIBCFS_USER_BITOPS_H__
44 /* test if bit nr is set in bitmap addr; returns previous value of bit nr */
45 static __inline__ int set_bit(int nr, unsigned long * addr)
49 addr += nr / BITS_PER_LONG;
50 mask = 1UL << (nr & (BITS_PER_LONG - 1));
51 nr = (mask & *addr) != 0;
56 /* clear bit nr in bitmap addr; returns previous value of bit nr*/
57 static __inline__ int clear_bit(int nr, unsigned long * addr)
61 addr += nr / BITS_PER_LONG;
62 mask = 1UL << (nr & (BITS_PER_LONG - 1));
63 nr = (mask & *addr) != 0;
68 static __inline__ int test_bit(int nr, const unsigned long * addr)
70 return ((1UL << (nr & (BITS_PER_LONG - 1))) & ((addr)[nr / BITS_PER_LONG])) != 0;
73 /* using binary seach */
74 static __inline__ unsigned long __ffs(long data)
78 #if BITS_PER_LONG == 64
79 if ((data & 0xFFFFFFFF) == 0) {
84 if ((data & 0xFFFF) == 0) {
88 if ((data & 0xFF) == 0) {
92 if ((data & 0xF) == 0) {
96 if ((data & 0x3) == 0) {
100 if ((data & 0x1) == 0)
106 #define __ffz(x) __ffs(~(x))
108 unsigned long find_next_bit(unsigned long *addr,
109 unsigned long size, unsigned long offset);
111 unsigned long find_next_zero_bit(unsigned long *addr,
112 unsigned long size, unsigned long offset);
114 #define find_first_bit(addr,size) (find_next_bit((addr),(size),0))
115 #define find_first_zero_bit(addr,size) (find_next_zero_bit((addr),(size),0))