/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*- * vim:expandtab:shiftwidth=8:tabstop=8: * * Copyright (C) 2007 Cluster File Systems, Inc. * * This file is part of Lustre, http://www.lustre.org. * * Lustre is free software; you can redistribute it and/or modify it under the * terms of version 2 of the GNU General Public License as published by the * Free Software Foundation. * * Lustre is distributed in the hope that it will be useful, but WITHOUT ANY * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more * details. * * You should have received a copy of the GNU General Public License along * with Lustre; if not, write to the Free Software Foundation, Inc., 675 Mass * Ave, Cambridge, MA 02139, USA. * */ #ifndef __KERNEL__ #include #include #include #define OFF_BY_START(start) ((start)/BITS_PER_LONG) unsigned long find_next_bit(unsigned long *addr, unsigned long size, unsigned long offset) { unsigned long *word, *last; unsigned long first_bit, bit, base; word = addr + OFF_BY_START(offset); last = addr + OFF_BY_START(size-1); first_bit = offset % BITS_PER_LONG; base = offset - first_bit; if (offset >= size) return size; if (first_bit != 0) { int tmp = (*word++) & (~0UL << first_bit); bit = __ffs(tmp); if (bit < BITS_PER_LONG) goto found; word++; base += BITS_PER_LONG; } while (word <= last) { if (*word != 0UL) { bit = __ffs(*word); goto found; } word++; base += BITS_PER_LONG; } return size; found: return base + bit; } unsigned long find_next_zero_bit(unsigned long *addr, unsigned long size, unsigned long offset) { unsigned long *word, *last; unsigned long first_bit, bit, base; word = addr + OFF_BY_START(offset); last = addr + OFF_BY_START(size-1); first_bit = offset % BITS_PER_LONG; base = offset - first_bit; if (offset >= size) return size; if (first_bit != 0) { int tmp = (*word++) & (~0UL << first_bit); bit = __ffz(tmp); if (bit < BITS_PER_LONG) goto found; word++; base += BITS_PER_LONG; } while (word <= last) { if (*word != ~0UL) { bit = __ffz(*word); goto found; } word++; base += BITS_PER_LONG; } return size; found: return base + bit; } #endif