2 files changed, 61 insertions, 0 deletions
diff --git a/Ryujinx.Cpu/MemoryManager.cs b/Ryujinx.Cpu/MemoryManager.cs
index 001c41f8..211a8c0d 100644
--- a/Ryujinx.Cpu/MemoryManager.cs
+++ b/Ryujinx.Cpu/MemoryManager.cs
@@ -194,6 +194,38 @@ namespace Ryujinx.Cpu
         }
 
         /// <summary>
+        /// Gets a region of memory that can be written to.
+        /// </summary>
+        /// <remarks>
+        /// If the requested region is not contiguous in physical memory,
+        /// this will perform an allocation, and flush the data (writing it
+        /// back to guest memory) on disposal.
+        /// </remarks>
+        /// <param name="va">Virtual address of the data</param>
+        /// <param name="size">Size of the data</param>
+        /// <returns>A writable region of memory containing the data</returns>
+        public WritableRegion GetWritableRegion(ulong va, int size)
+        {
+            if (size == 0)
+            {
+                return new WritableRegion(null, va, Memory<byte>.Empty);
+            }
+
+            if (IsContiguous(va, size))
+            {
+                return new WritableRegion(null, va, _backingMemory.GetMemory(GetPhysicalAddressInternal(va), size));
+            }
+            else
+            {
+                Memory<byte> memory = new byte[size];
+
+                GetSpan(va, size).CopyTo(memory.Span);
+
+                return new WritableRegion(this, va, memory);
+            }
+        }
+
+        /// <summary>
         /// Gets a reference for the given type at the specified virtual memory address.
         /// </summary>
         /// <remarks>
diff --git a/Ryujinx.Cpu/WritableRegion.cs b/Ryujinx.Cpu/WritableRegion.cs
new file mode 100644
index 00000000..5ea0a2d8
--- /dev/null
+++ b/Ryujinx.Cpu/WritableRegion.cs
@@ -0,0 +1,29 @@
+using System;
+
+namespace Ryujinx.Cpu
+{
+    public sealed class WritableRegion : IDisposable
+    {
+        private readonly MemoryManager _mm;
+        private readonly ulong _va;
+
+        private bool NeedsWriteback => _mm != null;
+
+        public Memory<byte> Memory { get; }
+
+        internal WritableRegion(MemoryManager mm, ulong va, Memory<byte> memory)
+        {
+            _mm = mm;
+            _va = va;
+            Memory = memory;
+        }
+
+        public void Dispose()
+        {
+            if (NeedsWriteback)
+            {
+                _mm.Write(_va, Memory.Span);
+            }
+        }
+    }
+}