/* find_last_bit.c: fallback find next bit implementation
   *
   * Copyright (C) 2008 IBM Corporation
   * Written by Rusty Russell <rusty@rustcorp.com.au>
   * (Inspired by David Howell's find_next_bit implementation)
   *
   * 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/bitops.h>
  #include <linux/export.h>
  #include <asm/types.h>
  #include <asm/byteorder.h>
  
  #ifndef find_last_bit
  
  unsigned long find_last_bit(const unsigned long *addr, unsigned long size)
  {
  	unsigned long words;
  	unsigned long tmp;
  
  	/* Start at final word. */
  	words = size / BITS_PER_LONG;
  
  	/* Partial final word? */
  	if (size & (BITS_PER_LONG-1)) {
  		tmp = (addr[words] & (~0UL >> (BITS_PER_LONG
  					 - (size & (BITS_PER_LONG-1)))));
  		if (tmp)
  			goto found;
  	}
  
  	while (words) {
  		tmp = addr[--words];
  		if (tmp) {
  found:
  			return words * BITS_PER_LONG + __fls(tmp);
  		}
  	}
  
  	/* Not found */
  	return size;
  }
  EXPORT_SYMBOL(find_last_bit);
  
  #endif