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/*
* linux/fs/ext4/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/buffer_head.h>
#include <linux/jbd2.h>
#include "ext4.h"
#ifdef EXT4FS_DEBUG
static const int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
unsigned long ext4_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;
}
#endif /* EXT4FS_DEBUG */
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