Merge branches 'arm/rockchip', 'arm/exynos', 'arm/smmu', 'x86/vt-d', 'x86/amd', ...

[sfrench/cifs-2.6.git] / include / linux / ktime.h

diff --git a/include/linux/ktime.h b/include/linux/ktime.h
index 5fc3d1083071ca24a96a6da038324fafae997667..2b6a204bd8d40cfb74db80e19bec216795366e33 100644 (file)
--- a/include/linux/ktime.h
+++ b/include/linux/ktime.h
@@ -166,19 +166,34 @@ static inline bool ktime_before(const ktime_t cmp1, const ktime_t cmp2)
 }
 
 #if BITS_PER_LONG < 64
-extern u64 __ktime_divns(const ktime_t kt, s64 div);
-static inline u64 ktime_divns(const ktime_t kt, s64 div)
+extern s64 __ktime_divns(const ktime_t kt, s64 div);
+static inline s64 ktime_divns(const ktime_t kt, s64 div)
 {
+       /*
+        * Negative divisors could cause an inf loop,
+        * so bug out here.
+        */
+       BUG_ON(div < 0);
        if (__builtin_constant_p(div) && !(div >> 32)) {
-               u64 ns = kt.tv64;
-               do_div(ns, div);
-               return ns;
+               s64 ns = kt.tv64;
+               u64 tmp = ns < 0 ? -ns : ns;
+
+               do_div(tmp, div);
+               return ns < 0 ? -tmp : tmp;
        } else {
                return __ktime_divns(kt, div);
        }
 }
 #else /* BITS_PER_LONG < 64 */
-# define ktime_divns(kt, div)          (u64)((kt).tv64 / (div))
+static inline s64 ktime_divns(const ktime_t kt, s64 div)
+{
+       /*
+        * 32-bit implementation cannot handle negative divisors,
+        * so catch them on 64bit as well.
+        */
+       WARN_ON(div < 0);
+       return kt.tv64 / div;
+}
 #endif
 
 static inline s64 ktime_to_us(const ktime_t kt)