/* find_next_bit.c: fallback find next bit implementation * * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include <linux/types.h> #include <linux/bitops.h> #define BITOP_WORD(nr) ((nr) / BITS_PER_LONG) /* * Find the next set bit in a memory region. */
unsigned long find_next_bit(const unsigned long *addr, unsigned long size, unsigned long offset) { const unsigned long *p = addr + BITOP_WORD(offset); unsigned long result = offset & ~(BITS_PER_LONG-1); unsigned long tmp; if (offset >= size) return size; size -= result; offset %= BITS_PER_LONG; if (offset) { tmp = *(p++); tmp &= (~0UL << offset); if (size < BITS_PER_LONG) goto found_first; if (tmp) goto found_middle; size -= BITS_PER_LONG; result += BITS_PER_LONG; } while (size & ~(BITS_PER_LONG-1)) { if ((tmp = *(p++))) goto found_middle; result += BITS_PER_LONG; size -= BITS_PER_LONG; } if (!size) return result; tmp = *p; found_first: tmp &= (~0UL >> (BITS_PER_LONG - size)); if (tmp == 0UL) /* Are any bits set? */ return result + size; /* Nope. */ found_middle: return result + __ffs(tmp); }Contributors
| Person | Tokens | Prop | Commits | CommitProp | |
| matthew wilcox | matthew wilcox | 201 | 100.00% | 1 | 100.00% |
| Total | 201 | 100.00% | 1 | 100.00% |
| Person | Tokens | Prop | Commits | CommitProp | |
| matthew wilcox | matthew wilcox | 216 | 100.00% | 1 | 100.00% |
| Total | 216 | 100.00% | 1 | 100.00% |