diff options
Diffstat (limited to 'fs/ext4/bitmap.c')
| -rw-r--r-- | fs/ext4/bitmap.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/fs/ext4/bitmap.c b/fs/ext4/bitmap.c new file mode 100644 index 000000000000..11e93c169bcf --- /dev/null +++ b/fs/ext4/bitmap.c @@ -0,0 +1,32 @@ +/* + * 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 <linux/ext4_fs.h> + +#ifdef EXT4FS_DEBUG + +static int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0}; + +unsigned long ext4_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 /* EXT4FS_DEBUG */ + |