kernel: add c++ support

arch/user/include/socks/machine/cpu.h

@@ -1,6 +1,10 @@
 #ifndef SOCKS_USER_CPU_H_
 #define SOCKS_USER_CPU_H_
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 typedef struct ml_cpu_block {
 	int cpu_reserved;
 } ml_cpu_block;
@@ -12,4 +16,8 @@ extern int ml_cpu_block_use(ml_cpu_block *p);
 
 extern void ml_halt_cpu(void);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif

arch/user/include/socks/machine/hwlock.h

@@ -3,6 +3,10 @@
 
 #define ML_HWLOCK_INIT (0)
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 typedef int ml_hwlock_t;
 
 extern void ml_hwlock_lock(ml_hwlock_t *lck);
@@ -11,4 +15,8 @@ extern void ml_hwlock_unlock(ml_hwlock_t *lck);
 extern void ml_hwlock_lock_irqsave(ml_hwlock_t *lck, unsigned long *flags);
 extern void ml_hwlock_unlock_irqrestore(ml_hwlock_t *lck, unsigned long flags);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif

arch/user/include/socks/machine/init.h

@@ -3,6 +3,10 @@
 
 #include <stdint.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #define __X2(x) #x
 #define __X(x) __X2(x)
 
@@ -18,4 +22,8 @@
 
 extern int ml_init(uintptr_t arg);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif

arch/user/include/socks/machine/vm.h

@@ -3,6 +3,10 @@
 
 #include <stdint.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 extern uintptr_t __pagemap_base(void);
 extern uintptr_t __pagemap_limit(void);
 
@@ -23,4 +27,8 @@ extern uintptr_t __pagemap_limit(void);
 #define VM_PAGE_MIN_ORDER VM_PAGE_4K
 #define VM_PAGE_MAX_ORDER VM_PAGE_8M
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif