qom/cpu: Add MemoryRegion property

Add a MemoryRegion property, which if set is used to construct
the CPU's initial (default) AddressSpace.

Backports commit 6731d864f80938e404dc3e5eb7f6b76b891e3e43 from qemu

qemu/cpus.c

@@ -88,8 +88,11 @@ int qemu_init_vcpu(CPUState *cpu)
         /* If the target cpu hasn't set up any address spaces itself,
          * give it the default one.
          */
+        AddressSpace *as = address_space_init_shareable(cpu->uc,
+                                                        cpu->memory,
+                                                        "cpu-memory");
         cpu->num_ases = 1;
-        cpu_address_space_init(cpu, &cpu->uc->as, 0);
+        cpu_address_space_init(cpu, as, 0);
     }
 
     if (tcg_enabled(cpu->uc)) {

qemu/exec.c

@@ -451,6 +451,25 @@ void cpu_exec_init(CPUState *cpu, void *opaque)
 
     // TODO: assert uc does not already have a cpu?
     uc->cpu = cpu;
+
+#ifndef CONFIG_USER_ONLY
+
+    // Unicorn: commented out
+    /* This is a softmmu CPU object, so create a property for it
+     * so users can wire up its memory. (This can't go in qom/cpu.c
+     * because that file is compiled only once for both user-mode
+     * and system builds.) The default if no link is set up is to use
+     * the system address space.
+     */
+    /*object_property_add_link(OBJECT(cpu), "memory", TYPE_MEMORY_REGION,
+                             (Object **)&cpu->memory,
+                             qdev_prop_allow_set_link_before_realize,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
+                             &error_abort);*/
+    cpu->memory = uc->system_memory;
+    // Unicorn: commented out
+    /*object_ref(OBJECT(cpu->memory)); */
+#endif
 }
 
 #if defined(CONFIG_USER_ONLY)

qemu/include/qom/cpu.h

@@ -264,6 +264,7 @@ struct CPUState {
     CPUAddressSpace *cpu_ases;
     int num_ases;
     AddressSpace *as;
+    MemoryRegion *memory;
 
     void *env_ptr; /* CPUArchState */
     struct TranslationBlock *current_tb;

qemu/unicorn_common.h

@@ -44,6 +44,8 @@ static void release_common(void *t)
 
     // TODO(danghvu): these function is not available outside qemu
     // so we keep them here instead of outside uc_close.
+    phys_mem_clean(&s->uc->as);
+    address_space_destroy(&s->uc->as);
     for (i = 0; i < s->uc->cpu->num_ases; i++) {
         AddressSpace *as = s->uc->cpu->cpu_ases[i].as;
         phys_mem_clean(as);