| /* | |
| * 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 int ext4_count_free(struct buffer_head *map, unsigned int numchars) | |
| { | |
| unsigned int i, 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 */ | |