[PATCH] i386: Add smp_ops interface

Add a smp_ops interface.  This abstracts the API defined by
<linux/smp.h> for use within arch/i386.  The primary intent is that it
be used by a paravirtualizing hypervisor to implement SMP, but it
could also be used by non-APIC-using sub-architectures.

This is related to CONFIG_PARAVIRT, but is implemented unconditionally
since it is simpler that way and not a highly performance-sensitive
interface.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/include/asm-i386/smp.h b/include/asm-i386/smp.h
index 9cab153..2d083cb 100644
--- a/include/asm-i386/smp.h
+++ b/include/asm-i386/smp.h
@@ -49,6 +49,59 @@
 extern void cpu_uninit(void);
 #endif
 
+struct smp_ops
+{
+	void (*smp_prepare_boot_cpu)(void);
+	void (*smp_prepare_cpus)(unsigned max_cpus);
+	int (*cpu_up)(unsigned cpu);
+	void (*smp_cpus_done)(unsigned max_cpus);
+
+	void (*smp_send_stop)(void);
+	void (*smp_send_reschedule)(int cpu);
+	int (*smp_call_function_mask)(cpumask_t mask,
+				      void (*func)(void *info), void *info,
+				      int wait);
+};
+
+extern struct smp_ops smp_ops;
+
+static inline void smp_prepare_boot_cpu(void)
+{
+	smp_ops.smp_prepare_boot_cpu();
+}
+static inline void smp_prepare_cpus(unsigned int max_cpus)
+{
+	smp_ops.smp_prepare_cpus(max_cpus);
+}
+static inline int __cpu_up(unsigned int cpu)
+{
+	return smp_ops.cpu_up(cpu);
+}
+static inline void smp_cpus_done(unsigned int max_cpus)
+{
+	smp_ops.smp_cpus_done(max_cpus);
+}
+
+static inline void smp_send_stop(void)
+{
+	smp_ops.smp_send_stop();
+}
+static inline void smp_send_reschedule(int cpu)
+{
+	smp_ops.smp_send_reschedule(cpu);
+}
+static inline int smp_call_function_mask(cpumask_t mask,
+					 void (*func) (void *info), void *info,
+					 int wait)
+{
+	return smp_ops.smp_call_function_mask(mask, func, info, wait);
+}
+
+void native_smp_prepare_boot_cpu(void);
+void native_smp_prepare_cpus(unsigned int max_cpus);
+int native_cpu_up(unsigned int cpunum);
+void native_smp_cpus_done(unsigned int max_cpus);
+
 #ifndef CONFIG_PARAVIRT
 #define startup_ipi_hook(phys_apicid, start_eip, start_esp) 		\
 do { } while (0)