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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/ext2/bitmap.c
downloadop-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
op-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/ext2/bitmap.c')
-rw-r--r--fs/ext2/bitmap.c25
1 files changed, 25 insertions, 0 deletions
diff --git a/fs/ext2/bitmap.c b/fs/ext2/bitmap.c
new file mode 100644
index 0000000..20145b7
--- /dev/null
+++ b/fs/ext2/bitmap.c
@@ -0,0 +1,25 @@
+/*
+ * 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/buffer_head.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);
+}
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