zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/fs/ext4/bitmap.c b/ap/os/linux/linux-3.4.x/fs/ext4/bitmap.c
new file mode 100644
index 0000000..bbde5d5
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/ext4/bitmap.c
@@ -0,0 +1,25 @@
+/*
+ * 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"
+
+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(char *bitmap, unsigned int numchars)
+{
+ unsigned int i, sum = 0;
+
+ for (i = 0; i < numchars; i++)
+ sum += nibblemap[bitmap[i] & 0xf] +
+ nibblemap[(bitmap[i] >> 4) & 0xf];
+ return sum;
+}
+