1 files changed, 49 insertions, 0 deletions

diff --git a/include/linux/calc64.h b/include/linux/calc64.h
new file mode 100644
index 000000000000..ebf4b8f38d88
--- /dev/null
+++ b/include/linux/calc64.h
@@ -0,0 +1,49 @@
+#ifndef _LINUX_CALC64_H
+#define _LINUX_CALC64_H
+
+#include <linux/types.h>
+#include <asm/div64.h>
+
+/*
+ * This is a generic macro which is used when the architecture
+ * specific div64.h does not provide a optimized one.
+ *
+ * The 64bit dividend is divided by the divisor (data type long), the
+ * result is returned and the remainder stored in the variable
+ * referenced by remainder (data type long *). In contrast to the
+ * do_div macro the dividend is kept intact.
+ */
+#ifndef div_long_long_rem
+#define div_long_long_rem(dividend, divisor, remainder) \
+        do_div_llr((dividend), divisor, remainder)
+
+static inline unsigned long do_div_llr(const long long dividend,
+                                       const long divisor, long *remainder)
+{
+        u64 result = dividend;
+
+        *(remainder) = do_div(result, divisor);
+        return (unsigned long) result;
+}
+#endif
+
+/*
+ * Sign aware variation of the above. On some architectures a
+ * negative dividend leads to an divide overflow exception, which
+ * is avoided by the sign check.
+ */
+static inline long div_long_long_rem_signed(const long long dividend,
+                                            const long divisor, long *remainder)
+{
+        long res;
+
+        if (unlikely(dividend < 0)) {
+                res = -div_long_long_rem(-dividend, divisor, remainder);
+                *remainder = -(*remainder);
+        } else
+                res = div_long_long_rem(dividend, divisor, remainder);
+
+        return res;
+}
+
+#endif