[tip:x86/asm] x86/asm/msr: Make wrmsrl_safe() a function

[tip-bot for Andy Lutomirski <tipbot@zytor.com>]

Commit-ID:  cf991de2f614f454b3cb2a300c06ecdf69f3a70d
Gitweb:     http://git.kernel.org/tip/cf991de2f614f454b3cb2a300c06ecdf69f3a70d
Author:     Andy Lutomirski <luto@kernel.org>
AuthorDate: Thu, 4 Jun 2015 17:13:44 -0700
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Fri, 5 Jun 2015 09:41:22 +0200

x86/asm/msr: Make wrmsrl_safe() a function

The wrmsrl_safe macro performs invalid shifts if the value
argument is 32 bits.  This makes it unnecessarily awkward to
write code that puts an unsigned long into an MSR.

Convert it to a real inline function.

For inspiration, see:

  7c74d5b7b7b6 ("x86/asm/entry/64: Fix MSR_IA32_SYSENTER_CS MSR value").

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: <linux-kernel@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
[ Applied small improvements. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 arch/x86/include/asm/msr.h | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h
index de36f22..13bf576 100644
--- a/arch/x86/include/asm/msr.h
+++ b/arch/x86/include/asm/msr.h
@@ -205,8 +205,13 @@ do {                                                            \
 
 #endif	/* !CONFIG_PARAVIRT */
 
-#define wrmsrl_safe(msr, val) wrmsr_safe((msr), (u32)(val),		\
-					     (u32)((val) >> 32))
+/*
+ * 64-bit version of wrmsr_safe():
+ */
+static inline int wrmsrl_safe(u32 msr, u64 val)
+{
+	return wrmsr_safe(msr, (u32)val,  (u32)(val >> 32));
+}
 
 #define write_tsc(low, high) wrmsr(MSR_IA32_TSC, (low), (high))