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/*

 *  linux/fs/ext2/bitmap.c

 *

 * Copyright (C) 1992, 1993, 1994, 1995

 * Remy Card (card@masi.ibp.fr)

 * Laboratoire MASI - Institut Blaise Pascal

 * Universite Pierre et Marie Curie (Paris VI)

 */

#include <linux/fs.h>

#include <linux/ext2_fs.h>

static int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};

unsigned long ext2_count_free (struct buffer_head * map, unsigned int numchars)

{

        unsigned int i;

        unsigned long sum = 0;

        if (!map)

                return (0);

        for (i = 0; i < numchars; i++)

                sum += nibblemap[map->b_data[i] & 0xf] +

                        nibblemap[(map->b_data[i] >> 4) & 0xf];

        return (sum);

}