summaryrefslogtreecommitdiff
path: root/ext2fs/bitmap.c
diff options
context:
space:
mode:
authorMiles Bader <miles@gnu.org>1995-04-11 02:25:14 +0000
committerMiles Bader <miles@gnu.org>1995-04-11 02:25:14 +0000
commit445d60d75f81a7428f80e29bdb59a4c2745a8bd5 (patch)
tree9185ef90be6c6302c31bf8099b77d801f25ab06c /ext2fs/bitmap.c
parent54ab36c50603b0e85ed1fe7af348a31cd3714c97 (diff)
Initial revision
Diffstat (limited to 'ext2fs/bitmap.c')
-rw-r--r--ext2fs/bitmap.c26
1 files changed, 26 insertions, 0 deletions
diff --git a/ext2fs/bitmap.c b/ext2fs/bitmap.c
new file mode 100644
index 00000000..8b9b5d23
--- /dev/null
+++ b/ext2fs/bitmap.c
@@ -0,0 +1,26 @@
+/*
+ * linux/fs/ext2/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/fs.h>
+#include <linux/ext2_fs.h>
+
+static int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
+
+unsigned long ext2_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);
+}