1 files changed, 276 insertions, 0 deletions
diff --git a/Ryujinx.Memory/MemoryBlock.cs b/Ryujinx.Memory/MemoryBlock.cs
new file mode 100644
index 00000000..850fb115
--- /dev/null
+++ b/Ryujinx.Memory/MemoryBlock.cs
@@ -0,0 +1,276 @@
+using System;
+using System.Runtime.CompilerServices;
+using System.Threading;
+
+namespace Ryujinx.Memory
+{
+    /// <summary>
+    /// Represents a block of contiguous physical guest memory.
+    /// </summary>
+    public sealed class MemoryBlock : IDisposable
+    {
+        private IntPtr _pointer;
+
+        /// <summary>
+        /// Pointer to the memory block data.
+        /// </summary>
+        public IntPtr Pointer => _pointer;
+
+        /// <summary>
+        /// Size of the memory block.
+        /// </summary>
+        public ulong Size { get; }
+
+        /// <summary>
+        /// Initializes a new instance of the memory block class.
+        /// </summary>
+        /// <param name="size">Size of the memory block</param>
+        /// <param name="flags">Flags that control memory block memory allocation</param>
+        /// <exception cref="OutOfMemoryException">Throw when there's no enough memory to allocate the requested size</exception>
+        /// <exception cref="PlatformNotSupportedException">Throw when the current platform is not supported</exception>
+        public MemoryBlock(ulong size, MemoryAllocationFlags flags = MemoryAllocationFlags.None)
+        {
+            if (flags.HasFlag(MemoryAllocationFlags.Reserve))
+            {
+                _pointer = MemoryManagement.Reserve(size);
+            }
+            else
+            {
+                _pointer = MemoryManagement.Allocate(size);
+            }
+
+            Size = size;
+        }
+
+        /// <summary>
+        /// Commits a region of memory that has previously been reserved.
+        /// This can be used to allocate memory on demand.
+        /// </summary>
+        /// <param name="offset">Starting offset of the range to be committed</param>
+        /// <param name="size">Size of the range to be committed</param>
+        /// <returns>True if the operation was successful, false otherwise</returns>
+        /// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
+        /// <exception cref="ArgumentOutOfRangeException">Throw when either <paramref name="offset"/> or <paramref name="size"/> are out of range</exception>
+        public bool Commit(ulong offset, ulong size)
+        {
+            return MemoryManagement.Commit(GetPointerInternal(offset, size), size);
+        }
+
+        /// <summary>
+        /// Reprotects a region of memory.
+        /// </summary>
+        /// <param name="offset">Starting offset of the range to be reprotected</param>
+        /// <param name="size">Size of the range to be reprotected</param>
+        /// <param name="permission">New memory permissions</param>
+        /// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
+        /// <exception cref="ArgumentOutOfRangeException">Throw when either <paramref name="offset"/> or <paramref name="size"/> are out of range</exception>
+        /// <exception cref="MemoryProtectionException">Throw when <paramref name="permission"/> is invalid</exception>
+        public void Reprotect(ulong offset, ulong size, MemoryPermission permission)
+        {
+            MemoryManagement.Reprotect(GetPointerInternal(offset, size), size, permission);
+        }
+
+        /// <summary>
+        /// Reads bytes from the memory block.
+        /// </summary>
+        /// <param name="offset">Starting offset of the range being read</param>
+        /// <param name="data">Span where the bytes being read will be copied to</param>
+        /// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
+        /// <exception cref="ArgumentOutOfRangeException">Throw when the memory region specified for the the data is out of range</exception>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public void Read(ulong offset, Span<byte> data)
+        {
+            GetSpan(offset, data.Length).CopyTo(data);
+        }
+
+        /// <summary>
+        /// Reads data from the memory block.
+        /// </summary>
+        /// <typeparam name="T">Type of the data</typeparam>
+        /// <param name="offset">Offset where the data is located</param>
+        /// <returns>Data at the specified address</returns>
+        /// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
+        /// <exception cref="ArgumentOutOfRangeException">Throw when the memory region specified for the the data is out of range</exception>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public T Read<T>(ulong offset) where T : unmanaged
+        {
+            return GetRef<T>(offset);
+        }
+
+        /// <summary>
+        /// Writes bytes to the memory block.
+        /// </summary>
+        /// <param name="offset">Starting offset of the range being written</param>
+        /// <param name="data">Span where the bytes being written will be copied from</param>
+        /// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
+        /// <exception cref="ArgumentOutOfRangeException">Throw when the memory region specified for the the data is out of range</exception>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public void Write(ulong offset, ReadOnlySpan<byte> data)
+        {
+            data.CopyTo(GetSpan(offset, data.Length));
+        }
+
+        /// <summary>
+        /// Writes data to the memory block.
+        /// </summary>
+        /// <typeparam name="T">Type of the data being written</typeparam>
+        /// <param name="offset">Offset to write the data into</param>
+        /// <param name="data">Data to be written</param>
+        /// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
+        /// <exception cref="ArgumentOutOfRangeException">Throw when the memory region specified for the the data is out of range</exception>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public void Write<T>(ulong offset, T data) where T : unmanaged
+        {
+            GetRef<T>(offset) = data;
+        }
+
+        /// <summary>
+        /// Copies data from one memory location to another.
+        /// </summary>
+        /// <param name="srcOffset">Source offset to read the data from</param>
+        /// <param name="dstOffset">Destination offset to write the data into</param>
+        /// <param name="size">Size of the copy in bytes</param>
+        /// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
+        /// <exception cref="ArgumentOutOfRangeException">Throw when <paramref name="srcOffset"/>, <paramref name="dstOffset"/> or <paramref name="size"/> is out of range</exception>
+        public void Copy(ulong srcOffset, ulong dstOffset, ulong size)
+        {
+            const int MaxChunkSize = 1 << 30;
+            
+            for (ulong offset = 0; offset < size; offset += MaxChunkSize)
+            {
+                int copySize = (int)Math.Min(MaxChunkSize, size - offset);
+
+                Write(dstOffset + offset, GetSpan(srcOffset + offset, copySize));
+            }   
+        }
+
+        /// <summary>
+        /// Fills a region of memory with zeros.
+        /// </summary>
+        /// <param name="offset">Offset of the region to fill with zeros</param>
+        /// <param name="size">Size in bytes of the region to fill</param>
+        /// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
+        /// <exception cref="ArgumentOutOfRangeException">Throw when either <paramref name="offset"/> or <paramref name="size"/> are out of range</exception>
+        public void ZeroFill(ulong offset, ulong size)
+        {
+            const int MaxChunkSize = 1 << 30;
+
+            for (ulong subOffset = 0; subOffset < size; subOffset += MaxChunkSize)
+            {
+                int copySize = (int)Math.Min(MaxChunkSize, size - subOffset);
+
+                GetSpan(offset + subOffset, copySize).Fill(0);
+            }
+        }
+
+        /// <summary>
+        /// Gets a reference of the data at a given memory block region.
+        /// </summary>
+        /// <typeparam name="T">Data type</typeparam>
+        /// <param name="offset">Offset of the memory region</param>
+        /// <returns>A reference to the given memory region data</returns>
+        /// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
+        /// <exception cref="ArgumentOutOfRangeException">Throw when either <paramref name="offset"/> or <paramref name="size"/> are out of range</exception>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public unsafe ref T GetRef<T>(ulong offset) where T : unmanaged
+        {
+            IntPtr ptr = _pointer;
+
+            if (ptr == IntPtr.Zero)
+            {
+                ThrowObjectDisposed();
+            }
+
+            int size = Unsafe.SizeOf<T>();
+
+            ulong endOffset = offset + (ulong)size;
+
+            if (endOffset > Size || endOffset < offset)
+            {
+                ThrowArgumentOutOfRange();
+            }
+
+            return ref Unsafe.AsRef<T>((void*)PtrAddr(ptr, offset));
+        }
+
+        /// <summary>
+        /// Gets the pointer of a given memory block region.
+        /// </summary>
+        /// <param name="offset">Start offset of the memory region</param>
+        /// <param name="size">Size in bytes of the region</param>
+        /// <returns>The pointer to the memory region</returns>
+        /// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
+        /// <exception cref="ArgumentOutOfRangeException">Throw when either <paramref name="offset"/> or <paramref name="size"/> are out of range</exception>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public IntPtr GetPointer(ulong offset, int size) => GetPointerInternal(offset, (ulong)size);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private IntPtr GetPointerInternal(ulong offset, ulong size)
+        {
+            IntPtr ptr = _pointer;
+
+            if (ptr == IntPtr.Zero)
+            {
+                ThrowObjectDisposed();
+            }
+
+            ulong endOffset = offset + size;
+
+            if (endOffset > Size || endOffset < offset)
+            {
+                ThrowArgumentOutOfRange();
+            }
+
+            return PtrAddr(ptr, offset);
+        }
+
+        /// <summary>
+        /// Gets the span of a given memory block region.
+        /// </summary>
+        /// <param name="offset">Start offset of the memory region</param>
+        /// <param name="size">Size in bytes of the region</param>
+        /// <returns>Span of the memory region</returns>
+        /// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
+        /// <exception cref="ArgumentOutOfRangeException">Throw when either <paramref name="offset"/> or <paramref name="size"/> are out of range</exception>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public unsafe Span<byte> GetSpan(ulong offset, int size)
+        {
+            return new Span<byte>((void*)GetPointer(offset, size), size);
+        }
+
+        /// <summary>
+        /// Adds a 64-bits offset to a native pointer.
+        /// </summary>
+        /// <param name="pointer">Native pointer</param>
+        /// <param name="offset">Offset to add</param>
+        /// <returns>Native pointer with the added offset</returns>
+        private IntPtr PtrAddr(IntPtr pointer, ulong offset)
+        {
+            return (IntPtr)(pointer.ToInt64() + (long)offset);
+        }
+
+        /// <summary>
+        /// Frees the memory allocated for this memory block.
+        /// </summary>
+        /// <remarks>
+        /// It's an error to use the memory block after disposal.
+        /// </remarks>
+        public void Dispose() => FreeMemory();
+
+        ~MemoryBlock() => FreeMemory();
+
+        private void FreeMemory()
+        {
+            IntPtr ptr = Interlocked.Exchange(ref _pointer, IntPtr.Zero);
+
+            // If pointer is null, the memory was already freed or never allocated.
+            if (ptr != IntPtr.Zero)
+            {
+                MemoryManagement.Free(ptr);
+            }
+        }
+
+        private void ThrowObjectDisposed() => throw new ObjectDisposedException(nameof(MemoryBlock));
+        private void ThrowArgumentOutOfRange() => throw new ArgumentOutOfRangeException();
+    }
+}