2 * Copyright (c) 2003 Marcel Moolenaar
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 * $FreeBSD: src/sys/gnu/fs/ext2fs/ext2_bitops.h,v 1.3 2006/04/13 19:37:32 cracauer Exp $
27 * $DragonFly: src/sys/vfs/gnu/ext2fs/ext2_bitops.h,v 1.1 2007/09/23 04:09:55 yanyh Exp $
30 #ifndef _SYS_GNU_EXT2FS_EXT2_BITOPS_H_
31 #define _SYS_GNU_EXT2FS_EXT2_BITOPS_H_
33 #define find_first_zero_bit(data, sz) find_next_zero_bit(data, sz, 0)
36 clear_bit(int no, void *data)
39 uint32_t mask, new, old;
41 p = (uint32_t*)data + (no >> 5);
42 mask = (1U << (no & 31));
46 } while (!atomic_cmpset_32(p, old, new));
51 set_bit(int no, void *data)
54 uint32_t mask, new, old;
56 p = (uint32_t*)data + (no >> 5);
57 mask = (1U << (no & 31));
61 } while (!atomic_cmpset_32(p, old, new));
66 test_bit(int no, void *data)
71 p = (uint32_t*)data + (no >> 5);
72 mask = (1U << (no & 31));
76 static __inline size_t
77 find_next_zero_bit(void *data, size_t sz, size_t ofs)
83 p = (uint32_t*)data + (ofs >> 5);
85 mask = ~0U << (ofs & 31);
88 return (ffs(~bit) + ofs - 1);
90 ofs = (ofs + 31U) & ~31U;
92 while(ofs < sz && *p == ~0U) {
99 return (ffs(~bit) + ofs - 1);
102 static __inline void *
103 memscan(void *data, int c, size_t sz)
108 while (sz && *p != c) {
115 #endif /* _SYS_GNU_EXT2FS_EXT2_BITOPS_H_ */