blob: e9983a0dd39674fe68133ac741a09385e384d61d [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/ext2/bitmap.c
3 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
8 */
9
Adrian Bunk4610a6b2006-01-09 20:54:05 -080010#ifdef EXT2FS_DEBUG
11
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/buffer_head.h>
13
Adrian Bunk4610a6b2006-01-09 20:54:05 -080014#include "ext2.h"
15
Linus Torvalds1da177e2005-04-16 15:20:36 -070016static int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
17
18unsigned long ext2_count_free (struct buffer_head * map, unsigned int numchars)
19{
20 unsigned int i;
21 unsigned long sum = 0;
22
23 if (!map)
24 return (0);
25 for (i = 0; i < numchars; i++)
26 sum += nibblemap[map->b_data[i] & 0xf] +
27 nibblemap[(map->b_data[i] >> 4) & 0xf];
28 return (sum);
29}
Adrian Bunk4610a6b2006-01-09 20:54:05 -080030
31#endif /* EXT2FS_DEBUG */
32