x86: provide read and write cr8 paravirt hooks

Since the cr8 manipulation functions ended up staying in the tree,
they can't be defined just when PARAVIRT is off: In this patch,
those functions are defined for the PARAVIRT case too.

[ mingo@elte.hu: fixes ]
Signed-off-by: NGlauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

include/asm-x86/paravirt.h

@@ -619,6 +619,7 @@ static inline void write_cr4(unsigned long x)
 	PVOP_VCALL1(pv_cpu_ops.write_cr4, x);
 }
 
+#ifdef CONFIG_X86_64
 static inline unsigned long read_cr8(void)
 {
 	return PVOP_CALL0(unsigned long, pv_cpu_ops.read_cr8);
@@ -628,6 +629,7 @@ static inline void write_cr8(unsigned long x)
 {
 	PVOP_VCALL1(pv_cpu_ops.write_cr8, x);
 }
+#endif
 
 static inline void raw_safe_halt(void)
 {

include/asm-x86/system.h

@@ -231,6 +231,20 @@ static inline void native_write_cr4(unsigned long val)
 	asm volatile("mov %0,%%cr4": :"r" (val), "m" (__force_order));
 }
 
+#ifdef CONFIG_X86_64
+static inline unsigned long native_read_cr8(void)
+{
+	unsigned long cr8;
+	asm volatile("movq %%cr8,%0" : "=r" (cr8));
+	return cr8;
+}
+
+static inline void native_write_cr8(unsigned long val)
+{
+	asm volatile("movq %0,%%cr8" :: "r" (val) : "memory");
+}
+#endif
+
 static inline void native_wbinvd(void)
 {
 	asm volatile("wbinvd": : :"memory");
@@ -248,21 +262,9 @@ static inline void native_wbinvd(void)
 #define read_cr4_safe()	(native_read_cr4_safe())
 #define write_cr4(x)	(native_write_cr4(x))
 #define wbinvd()	(native_wbinvd())
-
 #ifdef CONFIG_X86_64
-
-static inline unsigned long read_cr8(void)
-{
-	unsigned long cr8;
-	asm volatile("movq %%cr8,%0" : "=r" (cr8));
-	return cr8;
-}
-
-static inline void write_cr8(unsigned long val)
-{
-	asm volatile("movq %0,%%cr8" :: "r" (val) : "memory");
-}
-
+#define read_cr8()	(native_read_cr8())
+#define write_cr8(x)	(native_write_cr8(x))
 #endif
 
 /* Clear the 'TS' bit */