Btrfs-progs: cleanup duplicated division functions

div_factor has been implemented for two times, cleanup it.
And I move them into a independent file named math.h because they are
common math functions.

[Eric Sandeen: port kernel commit 3fed40c to userspace]

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/math.h b/math.h
new file mode 100644
index 00000000..482dba33
--- /dev/null
+++ b/math.h
@@ -0,0 +1,33 @@
+
+/*
+ * Copyright (C) 2012 Fujitsu.  All rights reserved.
+ * Written by Miao Xie <miaox@cn.fujitsu.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#ifndef __BTRFS_MATH_H
+#define __BTRFS_MATH_H
+
+static inline u64 div_factor(u64 num, int factor)
+{
+	if (factor == 10)
+		return num;
+	num *= factor;
+	num /= 10;
+	return num;
+}
+
+#endif