1 files changed, 22 insertions, 1 deletions

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 2b0a35e6bc69..edef168a0406 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -58,7 +58,18 @@ extern const char linux_proc_banner[];
 
 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
-#define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
+#define roundup(x, y) (                                 \
+{                                                       \
+        typeof(y) __y = y;                              \
+        (((x) + (__y - 1)) / __y) * __y;                \
+}                                                       \
+)
+#define rounddown(x, y) (                               \
+{                                                       \
+        typeof(x) __x = (x);                            \
+        __x - (__x % (y));                              \
+}                                                       \
+)
 #define DIV_ROUND_CLOSEST(x, divisor)(                  \
 {                                                       \
         typeof(divisor) __divisor = divisor;            \
@@ -641,6 +652,16 @@ static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
         _max1 > _max2 ? _max1 : _max2; })
 
 /**
+ * min_not_zero - return the minimum that is _not_ zero, unless both are zero
+ * @x: value1
+ * @y: value2
+ */
+#define min_not_zero(x, y) ({                   \
+        typeof(x) __x = (x);                    \
+        typeof(y) __y = (y);                    \
+        __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
+
+/**
  * clamp - return a value clamped to a given range with strict typechecking
  * @val: current value
  * @min: minimum allowable value