XObject CreateNative

src/xenia/kernel/objects/xthread.cc

@@ -144,17 +144,13 @@ uint8_t GetFakeCpuNumber(uint8_t proc_mask) {
 
 X_STATUS XThread::Create() {
   // Thread kernel object
-  // TODO: This is supposed to be preceded by X_OBJECT_HEADER, need to see if
-  // that's absolutely necessary.
-  thread_object_address_ = memory()->SystemHeapAlloc(sizeof(X_THREAD));
-  if (!thread_object_address_) {
+  // This call will also setup the native pointer for us.
+  uint8_t* guest_object = CreateNative(sizeof(X_THREAD));
+  if (!guest_object) {
     XELOGW("Unable to allocate thread object");
     return X_STATUS_NO_MEMORY;
   }
 
-  // Set native info.
-  SetNativePointer(thread_object_address_, true);
-
   // Allocate thread state block from heap.
   // This is set as r13 for user code and some special inlined Win32 calls
   // (like GetLastError/etc) will poke it directly.

src/xenia/kernel/objects/xthread.h

@@ -87,7 +87,6 @@ class XThread : public XObject {
 
   uint32_t pcr_ptr() const { return pcr_address_; }
   uint32_t thread_state_ptr() const { return thread_state_address_; }
-  uint32_t object_ptr() const { return thread_object_address_; }
 
   cpu::ThreadState* thread_state() const { return thread_state_; }
   uint32_t thread_id() const { return thread_id_; }
@@ -148,7 +147,6 @@ class XThread : public XObject {
   uint32_t tls_address_;
   uint32_t pcr_address_;
   uint32_t thread_state_address_;
-  uint32_t thread_object_address_; // Kernel object
   cpu::ThreadState* thread_state_;
 
   std::string name_;

src/xenia/kernel/xboxkrnl_ob.cc

@@ -77,7 +77,7 @@ SHIM_CALL ObReferenceObjectByHandle_shim(PPCContext* ppc_context,
           } break;*/
           case XObject::kTypeThread: {
             auto thread = object.get<XThread>();
-            native_ptr = thread->object_ptr();
+            native_ptr = thread->guest_object();
           } break;
           default: {
             assert_unhandled_case(object->type());
@@ -89,6 +89,8 @@ SHIM_CALL ObReferenceObjectByHandle_shim(PPCContext* ppc_context,
         assert(object->type() == XObject::kTypeSemaphore);
         auto sem = object.get<XSemaphore>();
 
+        native_ptr = sem->guest_object();
+
         // TODO(benvanik): implement.
         assert_unhandled_case(object_type_ptr);
         native_ptr = 0xDEADF00D;
@@ -97,7 +99,7 @@ SHIM_CALL ObReferenceObjectByHandle_shim(PPCContext* ppc_context,
         assert(object->type() == XObject::kTypeThread);
         auto thread = object.get<XThread>();
 
-        native_ptr = thread->object_ptr();
+        native_ptr = thread->guest_object();
       } break;
       default: {
         assert_unhandled_case(object_type_ptr);

src/xenia/kernel/xobject.cc

@@ -24,7 +24,9 @@ XObject::XObject(KernelState* kernel_state, Type type)
       handle_ref_count_(0),
       pointer_ref_count_(1),
       type_(type),
-      handle_(X_INVALID_HANDLE_VALUE) {
+      handle_(X_INVALID_HANDLE_VALUE),
+      guest_object_ptr_(0),
+      allocated_guest_object_(false) {
   // Added pointer check to support usage without a kernel_state
   if (kernel_state != nullptr) {
     kernel_state->object_table()->AddHandle(this, &handle_);
@@ -34,6 +36,11 @@ XObject::XObject(KernelState* kernel_state, Type type)
 XObject::~XObject() {
   assert_zero(handle_ref_count_);
   assert_zero(pointer_ref_count_);
+
+  if (allocated_guest_object_) {
+    uint32_t ptr = guest_object_ptr_ - sizeof(X_OBJECT_HEADER);
+    memory()->SystemHeapFree(ptr);
+  }
 }
 
 Emulator* XObject::emulator() const { return kernel_state_->emulator_; }
@@ -161,6 +168,38 @@ X_STATUS XObject::WaitMultiple(uint32_t count, XObject** objects,
   return result;
 }
 
+uint8_t* XObject::CreateNative(uint32_t size) {
+  std::lock_guard<xe::recursive_mutex> lock(kernel_state_->object_mutex());
+
+  uint32_t total_size = size + sizeof(X_OBJECT_HEADER);
+
+  auto mem = memory()->SystemHeapAlloc(total_size);
+  if (!mem) {
+    // Out of memory!
+    return nullptr;
+  }
+
+  allocated_guest_object_ = true;
+  memory()->Zero(mem, total_size);
+  guest_object_ptr_ = mem + sizeof(X_OBJECT_HEADER);
+  SetNativePointer(guest_object_ptr_, true);
+
+  auto header = memory()->TranslateVirtual<X_OBJECT_HEADER*>(mem);
+
+  auto creation_info =
+      memory()->SystemHeapAlloc(sizeof(X_OBJECT_CREATE_INFORMATION));
+  if (creation_info) {
+    memory()->Zero(creation_info, sizeof(X_OBJECT_CREATE_INFORMATION));
+
+    // Set it up in the header.
+    // Some kernel method is accessing this struct and dereferencing a member.
+    // With our current definition that member is non_paged_pool_charge.
+    header->object_create_info = creation_info;
+  }
+
+  return memory()->TranslateVirtual(guest_object_ptr_);
+}
+
 void XObject::SetNativePointer(uint32_t native_ptr, bool uninitialized) {
   std::lock_guard<xe::recursive_mutex> lock(kernel_state_->object_mutex());
 
@@ -173,6 +212,7 @@ void XObject::SetNativePointer(uint32_t native_ptr, bool uninitialized) {
   }
 
   // Stash pointer in struct.
+  // FIXME: This assumes the object has a dispatch header (some don't!)
   uint64_t object_ptr = reinterpret_cast<uint64_t>(this);
   object_ptr |= 0x1;
   header->wait_list_flink = (uint32_t)(object_ptr >> 32);
@@ -251,6 +291,7 @@ object_ref<XObject> XObject::GetNativeObject(KernelState* kernel_state,
     }
 
     // Stash pointer in struct.
+    // FIXME: This assumes the object contains a dispatch header (some don't!)
     uint64_t object_ptr = reinterpret_cast<uint64_t>(object);
     object_ptr |= 0x1;
     header->wait_list_flink = (uint32_t)(object_ptr >> 32);

src/xenia/kernel/xobject.h

@@ -76,6 +76,7 @@ struct X_OBJECT_HEADER {
   // (There's actually a body field here which is the object itself)
 };
 
+// http://www.nirsoft.net/kernel_struct/vista/OBJECT_CREATE_INFORMATION.html
 struct X_OBJECT_CREATE_INFORMATION {
   xe::be<uint32_t> attributes;
   xe::be<uint32_t> root_directory_ptr;
@@ -114,6 +115,7 @@ class XObject {
   Type type();
   X_HANDLE handle() const;
   const std::string& name() const { return name_; }
+  uint32_t guest_object() const { return guest_object_ptr_; }
 
   void RetainHandle();
   bool ReleaseHandle();
@@ -149,6 +151,8 @@ class XObject {
   virtual void* GetWaitHandle() { return 0; }
 
  protected:
+  // Creates the kernel object for guest code to use. Typically not needed.
+  uint8_t* CreateNative(uint32_t size);
   void SetNativePointer(uint32_t native_ptr, bool uninitialized = false);
 
   static uint32_t TimeoutTicksToMs(int64_t timeout_ticks);
@@ -162,6 +166,11 @@ class XObject {
   Type type_;
   X_HANDLE handle_;
   std::string name_;  // May be zero length.
+
+  // Guest pointer for kernel object. Remember: X_OBJECT_HEADER precedes this
+  // if we allocated it!
+  uint32_t guest_object_ptr_;
+  bool allocated_guest_object_;
 };
 
 template <typename T>