MemArena: Add Darwin implementation

Source/Core/Common/CMakeLists.txt

@@ -228,6 +228,11 @@ elseif(WIN32)
     Logging/ConsoleListenerWin.cpp
     MemArenaWin.cpp
   )
+elseif(APPLE)
+  target_sources(common PRIVATE
+    Logging/ConsoleListenerNix.cpp
+    MemArenaDarwin.cpp
+  )
 else()
   target_sources(common PRIVATE
     Logging/ConsoleListenerNix.cpp

Source/Core/Common/MemArena.h

@@ -7,6 +7,10 @@
 #include <string_view>
 #include <vector>
 
+#ifdef __APPLE__
+#include <mach/mach.h>
+#endif
+
 #include "Common/CommonTypes.h"
 #include "Common/DynamicLibrary.h"
 
@@ -120,6 +124,13 @@ class MemArena final
   void* m_reserved_region = nullptr;
   void* m_memory_handle = nullptr;
   WindowsMemoryFunctions m_memory_functions;
+#elif defined(__APPLE__)
+  vm_address_t m_shm_address = 0;
+  vm_size_t m_shm_size = 0;
+  mem_entry_name_port_t m_shm_entry = MACH_PORT_NULL;
+
+  vm_address_t m_region_address = 0;
+  vm_size_t m_region_size = 0;
 #else
   int m_shm_fd = 0;
   void* m_reserved_region = nullptr;

Source/Core/Common/MemArenaDarwin.cpp

@@ -0,0 +1,225 @@
+// Copyright 2025 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "Common/MemArena.h"
+
+#include "Common/Assert.h"
+#include "Common/Logging/Log.h"
+
+namespace Common
+{
+MemArena::MemArena() = default;
+MemArena::~MemArena() = default;
+
+void MemArena::GrabSHMSegment(size_t size, std::string_view base_name)
+{
+  kern_return_t retval = vm_allocate(mach_task_self(), &m_shm_address, size, VM_FLAGS_ANYWHERE);
+  if (retval != KERN_SUCCESS)
+  {
+    ERROR_LOG_FMT(MEMMAP, "GrabSHMSegment failed: vm_allocate returned {0:#x}", retval);
+
+    m_shm_address = 0;
+
+    return;
+  }
+
+  memory_object_size_t entry_size = size;
+  constexpr vm_prot_t prot = VM_PROT_READ | VM_PROT_WRITE;
+
+  retval = mach_make_memory_entry_64(mach_task_self(), &entry_size, m_shm_address, prot,
+                                     &m_shm_entry, MACH_PORT_NULL);
+  if (retval != KERN_SUCCESS)
+  {
+    ERROR_LOG_FMT(MEMMAP, "GrabSHMSegment failed: mach_make_memory_entry_64 returned {0:#x}",
+                  retval);
+
+    m_shm_address = 0;
+    m_shm_entry = MACH_PORT_NULL;
+
+    return;
+  }
+
+  m_shm_size = size;
+}
+
+void MemArena::ReleaseSHMSegment()
+{
+  if (m_shm_entry != MACH_PORT_NULL)
+  {
+    mach_port_deallocate(mach_task_self(), m_shm_entry);
+  }
+
+  if (m_shm_address != 0)
+  {
+    vm_deallocate(mach_task_self(), m_shm_address, m_shm_size);
+  }
+
+  m_shm_address = 0;
+  m_shm_size = 0;
+  m_shm_entry = MACH_PORT_NULL;
+}
+
+void* MemArena::CreateView(s64 offset, size_t size)
+{
+  if (m_shm_address == 0)
+  {
+    ERROR_LOG_FMT(MEMMAP, "CreateView failed: no shared memory segment allocated");
+    return nullptr;
+  }
+
+  vm_address_t address;
+  constexpr vm_prot_t prot = VM_PROT_READ | VM_PROT_WRITE;
+
+  kern_return_t retval = vm_map(mach_task_self(), &address, size, 0, VM_FLAGS_ANYWHERE, m_shm_entry,
+                                offset, false, prot, prot, VM_INHERIT_DEFAULT);
+  if (retval != KERN_SUCCESS)
+  {
+    ERROR_LOG_FMT(MEMMAP, "CreateView failed: vm_map returned {0:#x}", retval);
+    return nullptr;
+  }
+
+  return reinterpret_cast<void*>(address);
+}
+
+void MemArena::ReleaseView(void* view, size_t size)
+{
+  vm_deallocate(mach_task_self(), reinterpret_cast<vm_address_t>(view), size);
+}
+
+u8* MemArena::ReserveMemoryRegion(size_t memory_size)
+{
+  vm_address_t address;
+
+  kern_return_t retval = vm_allocate(mach_task_self(), &address, memory_size, VM_FLAGS_ANYWHERE);
+  if (retval != KERN_SUCCESS)
+  {
+    ERROR_LOG_FMT(MEMMAP, "ReserveMemoryRegion: vm_allocate returned {0:#x}", retval);
+    return nullptr;
+  }
+
+  retval = vm_protect(mach_task_self(), address, memory_size, true, VM_PROT_NONE);
+  if (retval != KERN_SUCCESS)
+  {
+    ERROR_LOG_FMT(MEMMAP, "ReserveMemoryRegion failed: vm_prot returned {0:#x}", retval);
+    return nullptr;
+  }
+
+  m_region_address = address;
+  m_region_size = memory_size;
+
+  return reinterpret_cast<u8*>(m_region_address);
+}
+
+void MemArena::ReleaseMemoryRegion()
+{
+  if (m_region_address != 0)
+  {
+    vm_deallocate(mach_task_self(), m_region_address, m_region_size);
+  }
+
+  m_region_address = 0;
+  m_region_size = 0;
+}
+
+void* MemArena::MapInMemoryRegion(s64 offset, size_t size, void* base)
+{
+  if (m_shm_address == 0)
+  {
+    ERROR_LOG_FMT(MEMMAP, "MapInMemoryRegion failed: no shared memory segment allocated");
+    return nullptr;
+  }
+
+  vm_address_t address = reinterpret_cast<vm_address_t>(base);
+  constexpr vm_prot_t prot = VM_PROT_READ | VM_PROT_WRITE;
+
+  kern_return_t retval =
+      vm_map(mach_task_self(), &address, size, 0, VM_FLAGS_FIXED | VM_FLAGS_OVERWRITE, m_shm_entry,
+             offset, false, prot, prot, VM_INHERIT_DEFAULT);
+  if (retval != KERN_SUCCESS)
+  {
+    ERROR_LOG_FMT(MEMMAP, "MapInMemoryRegion failed: vm_map returned {0:#x}", retval);
+    return nullptr;
+  }
+
+  return reinterpret_cast<void*>(address);
+}
+
+void MemArena::UnmapFromMemoryRegion(void* view, size_t size)
+{
+  vm_address_t address = reinterpret_cast<vm_address_t>(view);
+
+  kern_return_t retval =
+      vm_allocate(mach_task_self(), &address, size, VM_FLAGS_FIXED | VM_FLAGS_OVERWRITE);
+  if (retval != KERN_SUCCESS)
+  {
+    ERROR_LOG_FMT(MEMMAP, "UnmapFromMemoryRegion failed: vm_allocate returned {0:#x}", retval);
+    return;
+  }
+
+  retval = vm_protect(mach_task_self(), address, size, true, VM_PROT_NONE);
+  if (retval != KERN_SUCCESS)
+  {
+    ERROR_LOG_FMT(MEMMAP, "UnmapFromMemoryRegion failed: vm_prot returned {0:#x}", retval);
+  }
+}
+
+LazyMemoryRegion::LazyMemoryRegion() = default;
+
+LazyMemoryRegion::~LazyMemoryRegion()
+{
+  Release();
+}
+
+void* LazyMemoryRegion::Create(size_t size)
+{
+  ASSERT(!m_memory);
+
+  if (size == 0)
+    return nullptr;
+
+  vm_address_t memory = 0;
+
+  kern_return_t retval = vm_allocate(mach_task_self(), &memory, size, VM_FLAGS_ANYWHERE);
+  if (retval != KERN_SUCCESS)
+  {
+    ERROR_LOG_FMT(MEMMAP, "Failed to allocate memory space: {0:#x}", retval);
+    return nullptr;
+  }
+
+  m_memory = reinterpret_cast<void*>(memory);
+  m_size = size;
+
+  return m_memory;
+}
+
+void LazyMemoryRegion::Clear()
+{
+  ASSERT(m_memory);
+
+  vm_address_t new_memory = reinterpret_cast<vm_address_t>(m_memory);
+
+  kern_return_t retval =
+      vm_allocate(mach_task_self(), &new_memory, m_size, VM_FLAGS_FIXED | VM_FLAGS_OVERWRITE);
+  if (retval != KERN_SUCCESS)
+  {
+    ERROR_LOG_FMT(MEMMAP, "Failed to reallocate memory space: {0:#x}", retval);
+
+    m_memory = nullptr;
+
+    return;
+  }
+
+  m_memory = reinterpret_cast<void*>(new_memory);
+}
+
+void LazyMemoryRegion::Release()
+{
+  if (m_memory)
+  {
+    vm_deallocate(mach_task_self(), reinterpret_cast<vm_address_t>(m_memory), m_size);
+  }
+
+  m_memory = nullptr;
+  m_size = 0;
+}
+}  // namespace Common