cleanup

arch/x86_64/mem.c

@@ -1,4 +1,5 @@
 #include <zinnia/types.h>
+#include <arch/mem.h>
 #include <stddef.h>
 #include <stdint.h>
 
@@ -29,3 +30,7 @@ uintptr_t arch_mem_pfndb_addr() {
 uintptr_t arch_mem_mapping_addr() {
     return 0xFFFF'C000'0000'0000;
 }
+
+bool arch_mem_addr_is_user(uintptr_t addr) {
+    return addr < 0x0000'8000'0000'0000;
+}