[mirror_ubuntu-bionic-kernel.git] / fs / ext3 / bitmap.c

/*
 *  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)
 */

#include <linux/buffer_head.h>
#include <linux/jbd.h>
#include <linux/ext3_fs.h>

#ifdef EXT3FS_DEBUG

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

unsigned long ext3_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  /*  EXT3FS_DEBUG  */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/ext3/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
	10	#include <linux/buffer_head.h>
c1f5a194 KT	11	#include <linux/jbd.h>
c1f5a194 KT	12	#include <linux/ext3_fs.h>
3af13763	13
c1f5a194	14	#ifdef EXT3FS_DEBUG
1da177e4	15
febfcf91	16	static const int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
1da177e4 LT	17
	18	unsigned long ext3_count_free (struct buffer_head * map, unsigned int numchars)
	19	{
	20	unsigned int i;
	21	unsigned long sum = 0;
	22
ae6ddcc5	23	if (!map)
1da177e4 LT	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	}
3af13763 AB	30
	31	#endif /* EXT3FS_DEBUG */
	32