2005-04-17 06:20:36 +08:00
|
|
|
/*
|
|
|
|
* linux/fs/ext3/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)
|
|
|
|
*/
|
|
|
|
|
2012-03-30 10:30:07 +08:00
|
|
|
#include "ext3.h"
|
2006-01-10 12:54:06 +08:00
|
|
|
|
2006-03-25 19:07:47 +08:00
|
|
|
#ifdef EXT3FS_DEBUG
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2007-10-17 14:26:15 +08:00
|
|
|
static const int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
unsigned long ext3_count_free (struct buffer_head * map, unsigned int numchars)
|
|
|
|
{
|
|
|
|
unsigned int i;
|
|
|
|
unsigned long sum = 0;
|
|
|
|
|
2006-09-27 16:49:27 +08:00
|
|
|
if (!map)
|
2005-04-17 06:20:36 +08:00
|
|
|
return (0);
|
|
|
|
for (i = 0; i < numchars; i++)
|
|
|
|
sum += nibblemap[map->b_data[i] & 0xf] +
|
|
|
|
nibblemap[(map->b_data[i] >> 4) & 0xf];
|
|
|
|
return (sum);
|
|
|
|
}
|
2006-01-10 12:54:06 +08:00
|
|
|
|
|
|
|
#endif /* EXT3FS_DEBUG */
|
|
|
|
|