kernel.h: define u8, s8, u32, etc. limits

commit 89a0714106aac7309c7dfa0f004b39e1e89d2942 upstream.

Create constants that define the maximum and minimum values
representable by the kernel types u8, s8, u16, s16, and so on.

Signed-off-by: Alex Elder <elder@linaro.org>
Cc: Sage Weil <sage@inktank.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index e9ef6d6b51d5b07f6471e96dc20efa5685416220..341551c7b4c82d265d6f511442459911206de7f3 100644 (file)
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -29,6 +29,19 @@
 #define ULLONG_MAX     (~0ULL)
 #define SIZE_MAX       (~(size_t)0)
 
+#define U8_MAX         ((u8)~0U)
+#define S8_MAX         ((s8)(U8_MAX>>1))
+#define S8_MIN         ((s8)(-S8_MAX - 1))
+#define U16_MAX                ((u16)~0U)
+#define S16_MAX                ((s16)(U16_MAX>>1))
+#define S16_MIN                ((s16)(-S16_MAX - 1))
+#define U32_MAX                ((u32)~0U)
+#define S32_MAX                ((s32)(U32_MAX>>1))
+#define S32_MIN                ((s32)(-S32_MAX - 1))
+#define U64_MAX                ((u64)~0ULL)
+#define S64_MAX                ((s64)(U64_MAX>>1))
+#define S64_MIN                ((s64)(-S64_MAX - 1))
+
 #define STACK_MAGIC    0xdeadbeef
 
 #define REPEAT_BYTE(x) ((~0ul / 0xff) * (x))