1 files changed, 130 insertions, 0 deletions
diff --git a/src/Ryujinx.HLE/HOS/Kernel/Memory/KTransferMemory.cs b/src/Ryujinx.HLE/HOS/Kernel/Memory/KTransferMemory.cs
new file mode 100644
index 00000000..b2449598
--- /dev/null
+++ b/src/Ryujinx.HLE/HOS/Kernel/Memory/KTransferMemory.cs
@@ -0,0 +1,130 @@
+using Ryujinx.Common;
+using Ryujinx.HLE.HOS.Kernel.Common;
+using Ryujinx.HLE.HOS.Kernel.Process;
+using Ryujinx.Horizon.Common;
+using System;
+
+namespace Ryujinx.HLE.HOS.Kernel.Memory
+{
+    class KTransferMemory : KAutoObject
+    {
+        private KProcess _creator;
+
+        // TODO: Remove when we no longer need to read it from the owner directly.
+        public KProcess Creator => _creator;
+
+        private readonly KPageList _pageList;
+
+        public ulong Address { get; private set; }
+        public ulong Size { get; private set; }
+
+        public KMemoryPermission Permission { get; private set; }
+
+        private bool _hasBeenInitialized;
+        private bool _isMapped;
+
+        public KTransferMemory(KernelContext context) : base(context)
+        {
+            _pageList = new KPageList();
+        }
+
+        public KTransferMemory(KernelContext context, SharedMemoryStorage storage) : base(context)
+        {
+            _pageList = storage.GetPageList();
+            Permission = KMemoryPermission.ReadAndWrite;
+
+            _hasBeenInitialized = true;
+            _isMapped = false;
+        }
+
+        public Result Initialize(ulong address, ulong size, KMemoryPermission permission)
+        {
+            KProcess creator = KernelStatic.GetCurrentProcess();
+
+            _creator = creator;
+
+            Result result = creator.MemoryManager.BorrowTransferMemory(_pageList, address, size, permission);
+
+            if (result != Result.Success)
+            {
+                return result;
+            }
+
+            creator.IncrementReferenceCount();
+
+            Permission = permission;
+            Address = address;
+            Size = size;
+            _hasBeenInitialized = true;
+            _isMapped = false;
+
+            return result;
+        }
+
+        public Result MapIntoProcess(
+            KPageTableBase memoryManager,
+            ulong address,
+            ulong size,
+            KProcess process,
+            KMemoryPermission permission)
+        {
+            if (_pageList.GetPagesCount() != BitUtils.DivRoundUp<ulong>(size, KPageTableBase.PageSize))
+            {
+                return KernelResult.InvalidSize;
+            }
+
+            if (permission != Permission || _isMapped)
+            {
+                return KernelResult.InvalidState;
+            }
+
+            MemoryState state = Permission == KMemoryPermission.None ? MemoryState.TransferMemoryIsolated : MemoryState.TransferMemory;
+
+            Result result = memoryManager.MapPages(address, _pageList, state, KMemoryPermission.ReadAndWrite);
+
+            if (result == Result.Success)
+            {
+                _isMapped = true;
+            }
+
+            return result;
+        }
+
+        public Result UnmapFromProcess(
+            KPageTableBase memoryManager,
+            ulong address,
+            ulong size,
+            KProcess process)
+        {
+            if (_pageList.GetPagesCount() != BitUtils.DivRoundUp<ulong>(size, (ulong)KPageTableBase.PageSize))
+            {
+                return KernelResult.InvalidSize;
+            }
+
+            MemoryState state = Permission == KMemoryPermission.None ? MemoryState.TransferMemoryIsolated : MemoryState.TransferMemory;
+
+            Result result = memoryManager.UnmapPages(address, _pageList, state);
+
+            if (result == Result.Success)
+            {
+                _isMapped = false;
+            }
+
+            return result;
+        }
+
+        protected override void Destroy()
+        {
+            if (_hasBeenInitialized)
+            {
+                if (!_isMapped && _creator.MemoryManager.UnborrowTransferMemory(Address, Size, _pageList) != Result.Success)
+                {
+                    throw new InvalidOperationException("Unexpected failure restoring transfer memory attributes.");
+                }
+
+                _creator.ResourceLimit?.Release(LimitableResource.TransferMemory, 1);
+                _creator.DecrementReferenceCount();
+            }
+        }
+    }
+}
+\ No newline at end of file