| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> | 
| Kirk True | c1f5a19 | 2006-03-25 03:07:47 -0800 | [diff] [blame] | 11 | #include <linux/jbd.h> | 
 | 12 | #include <linux/ext3_fs.h> | 
| Adrian Bunk | 3af1376 | 2006-01-09 20:54:06 -0800 | [diff] [blame] | 13 |  | 
| Kirk True | c1f5a19 | 2006-03-25 03:07:47 -0800 | [diff] [blame] | 14 | #ifdef EXT3FS_DEBUG | 
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 |  | 
 | 16 | static int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0}; | 
 | 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 |  | 
 | 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 Bunk | 3af1376 | 2006-01-09 20:54:06 -0800 | [diff] [blame] | 30 |  | 
 | 31 | #endif  /*  EXT3FS_DEBUG  */ | 
 | 32 |  |