x86: puts read and write cr8 into pv_cpu_ops

This patch adds room for read and write_cr8 functions back in
pv_cpu_ops struct
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

@@ -101,6 +101,11 @@ struct pv_cpu_ops {
 	unsigned long (*read_cr4)(void);
 	void (*write_cr4)(unsigned long);
 
+#ifdef CONFIG_X86_64
+	unsigned long (*read_cr8)(void);
+	void (*write_cr8)(unsigned long);
+#endif
+
 	/* Segment descriptor handling */
 	void (*load_tr_desc)(void);
 	void (*load_gdt)(const struct desc_ptr *);
@@ -614,6 +619,16 @@ static inline void write_cr4(unsigned long x)
 	PVOP_VCALL1(pv_cpu_ops.write_cr4, x);
 }
 
+static inline unsigned long read_cr8(void)
+{
+	return PVOP_CALL0(unsigned long, pv_cpu_ops.read_cr8);
+}
+
+static inline void write_cr8(unsigned long x)
+{
+	PVOP_VCALL1(pv_cpu_ops.write_cr8, x);
+}
+
 static inline void raw_safe_halt(void)
 {
 	PVOP_VCALL0(pv_irq_ops.safe_halt);