1 files changed, 214 insertions, 1 deletions
diff --git a/src/Ryujinx.Graphics.Gpu/Memory/Buffer.cs b/src/Ryujinx.Graphics.Gpu/Memory/Buffer.cs
index 12461e96..e01e5142 100644
--- a/src/Ryujinx.Graphics.Gpu/Memory/Buffer.cs
+++ b/src/Ryujinx.Graphics.Gpu/Memory/Buffer.cs
@@ -5,6 +5,8 @@ using Ryujinx.Memory.Tracking;
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Runtime.CompilerServices;
+using System.Threading;
 
 namespace Ryujinx.Graphics.Gpu.Memory
 {
@@ -65,6 +67,9 @@ namespace Ryujinx.Graphics.Gpu.Memory
         private readonly Action<ulong, ulong> _loadDelegate;
         private readonly Action<ulong, ulong> _modifiedDelegate;
 
+        private HashSet<MultiRangeBuffer> _virtualDependencies;
+        private readonly ReaderWriterLockSlim _virtualDependenciesLock;
+
         private int _sequenceNumber;
 
         private readonly bool _useGranular;
@@ -152,6 +157,8 @@ namespace Ryujinx.Graphics.Gpu.Memory
             _externalFlushDelegate = new RegionSignal(ExternalFlush);
             _loadDelegate = new Action<ulong, ulong>(LoadRegion);
             _modifiedDelegate = new Action<ulong, ulong>(RegionModified);
+
+            _virtualDependenciesLock = new ReaderWriterLockSlim();
         }
 
         /// <summary>
@@ -220,6 +227,7 @@ namespace Ryujinx.Graphics.Gpu.Memory
         /// </remarks>
         /// <param name="address">Start address of the range to synchronize</param>
         /// <param name="size">Size in bytes of the range to synchronize</param>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public void SynchronizeMemory(ulong address, ulong size)
         {
             if (_useGranular)
@@ -239,6 +247,7 @@ namespace Ryujinx.Graphics.Gpu.Memory
                     else
                     {
                         _context.Renderer.SetBufferData(Handle, 0, _physicalMemory.GetSpan(Address, (int)Size));
+                        CopyToDependantVirtualBuffers();
                     }
 
                     _sequenceNumber = _context.SequenceNumber;
@@ -460,6 +469,8 @@ namespace Ryujinx.Graphics.Gpu.Memory
             int offset = (int)(mAddress - Address);
 
             _context.Renderer.SetBufferData(Handle, offset, _physicalMemory.GetSpan(mAddress, (int)mSize));
+
+            CopyToDependantVirtualBuffers(mAddress, mSize);
         }
 
         /// <summary>
@@ -520,6 +531,7 @@ namespace Ryujinx.Graphics.Gpu.Memory
         /// <param name="dstOffset">The offset of the destination buffer to copy into</param>
         public void CopyTo(Buffer destination, int dstOffset)
         {
+            CopyFromDependantVirtualBuffers();
             _context.Renderer.Pipeline.CopyBuffer(Handle, destination.Handle, 0, dstOffset, (int)Size);
         }
 
@@ -536,7 +548,7 @@ namespace Ryujinx.Graphics.Gpu.Memory
             using PinnedSpan<byte> data = _context.Renderer.GetBufferData(Handle, offset, (int)size);
 
             // TODO: When write tracking shaders, they will need to be aware of changes in overlapping buffers.
-            _physicalMemory.WriteUntracked(address, data.Get());
+            _physicalMemory.WriteUntracked(address, CopyFromDependantVirtualBuffers(data.Get(), address, size));
         }
 
         /// <summary>
@@ -618,6 +630,207 @@ namespace Ryujinx.Graphics.Gpu.Memory
         }
 
         /// <summary>
+        /// Adds a virtual buffer dependency, indicating that a virtual buffer depends on data from this buffer.
+        /// </summary>
+        /// <param name="virtualBuffer">Dependant virtual buffer</param>
+        public void AddVirtualDependency(MultiRangeBuffer virtualBuffer)
+        {
+            _virtualDependenciesLock.EnterWriteLock();
+
+            try
+            {
+                (_virtualDependencies ??= new()).Add(virtualBuffer);
+            }
+            finally
+            {
+                _virtualDependenciesLock.ExitWriteLock();
+            }
+        }
+
+        /// <summary>
+        /// Removes a virtual buffer dependency, indicating that a virtual buffer no longer depends on data from this buffer.
+        /// </summary>
+        /// <param name="virtualBuffer">Dependant virtual buffer</param>
+        public void RemoveVirtualDependency(MultiRangeBuffer virtualBuffer)
+        {
+            _virtualDependenciesLock.EnterWriteLock();
+
+            try
+            {
+                if (_virtualDependencies != null)
+                {
+                    _virtualDependencies.Remove(virtualBuffer);
+
+                    if (_virtualDependencies.Count == 0)
+                    {
+                        _virtualDependencies = null;
+                    }
+                }
+            }
+            finally
+            {
+                _virtualDependenciesLock.ExitWriteLock();
+            }
+        }
+
+        /// <summary>
+        /// Copies the buffer data to all virtual buffers that depends on it.
+        /// </summary>
+        public void CopyToDependantVirtualBuffers()
+        {
+            CopyToDependantVirtualBuffers(Address, Size);
+        }
+
+        /// <summary>
+        /// Copies the buffer data inside the specifide range to all virtual buffers that depends on it.
+        /// </summary>
+        /// <param name="address">Address of the range</param>
+        /// <param name="size">Size of the range in bytes</param>
+        public void CopyToDependantVirtualBuffers(ulong address, ulong size)
+        {
+            if (_virtualDependencies != null)
+            {
+                foreach (var virtualBuffer in _virtualDependencies)
+                {
+                    CopyToDependantVirtualBuffer(virtualBuffer, address, size);
+                }
+            }
+        }
+
+        /// <summary>
+        /// Copies all modified ranges from all virtual buffers back into this buffer.
+        /// </summary>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public void CopyFromDependantVirtualBuffers()
+        {
+            if (_virtualDependencies != null)
+            {
+                CopyFromDependantVirtualBuffersImpl();
+            }
+        }
+
+        /// <summary>
+        /// Copies all modified ranges from all virtual buffers back into this buffer.
+        /// </summary>
+        [MethodImpl(MethodImplOptions.NoInlining)]
+        private void CopyFromDependantVirtualBuffersImpl()
+        {
+            foreach (var virtualBuffer in _virtualDependencies.OrderBy(x => x.ModificationSequenceNumber))
+            {
+                virtualBuffer.ConsumeModifiedRegion(this, (mAddress, mSize) =>
+                {
+                    // Get offset inside both this and the virtual buffer.
+                    // Note that sometimes there is no right answer for the virtual offset,
+                    // as the same physical range might be mapped multiple times inside a virtual buffer.
+                    // We just assume it does not happen in practice as it can only be implemented correctly
+                    // when the host has support for proper sparse mapping.
+
+                    ulong mEndAddress = mAddress + mSize;
+                    mAddress = Math.Max(mAddress, Address);
+                    mSize = Math.Min(mEndAddress, EndAddress) - mAddress;
+
+                    int physicalOffset = (int)(mAddress - Address);
+                    int virtualOffset = virtualBuffer.Range.FindOffset(new(mAddress, mSize));
+
+                    _context.Renderer.Pipeline.CopyBuffer(virtualBuffer.Handle, Handle, virtualOffset, physicalOffset, (int)mSize);
+                });
+            }
+        }
+
+        /// <summary>
+        /// Copies all overlapping modified ranges from all virtual buffers back into this buffer, and returns an updated span with the data.
+        /// </summary>
+        /// <param name="dataSpan">Span where the unmodified data will be taken from for the output</param>
+        /// <param name="address">Address of the region to copy</param>
+        /// <param name="size">Size of the region to copy in bytes</param>
+        /// <returns>A span with <paramref name="dataSpan"/>, and the data for all modified ranges if any</returns>
+        private ReadOnlySpan<byte> CopyFromDependantVirtualBuffers(ReadOnlySpan<byte> dataSpan, ulong address, ulong size)
+        {
+            _virtualDependenciesLock.EnterReadLock();
+
+            try
+            {
+                if (_virtualDependencies != null)
+                {
+                    byte[] storage = dataSpan.ToArray();
+
+                    foreach (var virtualBuffer in _virtualDependencies.OrderBy(x => x.ModificationSequenceNumber))
+                    {
+                        virtualBuffer.ConsumeModifiedRegion(address, size, (mAddress, mSize) =>
+                        {
+                            // Get offset inside both this and the virtual buffer.
+                            // Note that sometimes there is no right answer for the virtual offset,
+                            // as the same physical range might be mapped multiple times inside a virtual buffer.
+                            // We just assume it does not happen in practice as it can only be implemented correctly
+                            // when the host has support for proper sparse mapping.
+
+                            ulong mEndAddress = mAddress + mSize;
+                            mAddress = Math.Max(mAddress, address);
+                            mSize = Math.Min(mEndAddress, address + size) - mAddress;
+
+                            int physicalOffset = (int)(mAddress - Address);
+                            int virtualOffset = virtualBuffer.Range.FindOffset(new(mAddress, mSize));
+
+                            _context.Renderer.Pipeline.CopyBuffer(virtualBuffer.Handle, Handle, virtualOffset, physicalOffset, (int)size);
+                            virtualBuffer.GetData(storage.AsSpan().Slice((int)(mAddress - address), (int)mSize), virtualOffset, (int)mSize);
+                        });
+                    }
+
+                    dataSpan = storage;
+                }
+            }
+            finally
+            {
+                _virtualDependenciesLock.ExitReadLock();
+            }
+
+            return dataSpan;
+        }
+
+        /// <summary>
+        /// Copies the buffer data to the specified virtual buffer.
+        /// </summary>
+        /// <param name="virtualBuffer">Virtual buffer to copy the data into</param>
+        public void CopyToDependantVirtualBuffer(MultiRangeBuffer virtualBuffer)
+        {
+            CopyToDependantVirtualBuffer(virtualBuffer, Address, Size);
+        }
+
+        /// <summary>
+        /// Copies the buffer data inside the given range to the specified virtual buffer.
+        /// </summary>
+        /// <param name="virtualBuffer">Virtual buffer to copy the data into</param>
+        /// <param name="address">Address of the range</param>
+        /// <param name="size">Size of the range in bytes</param>
+        public void CopyToDependantVirtualBuffer(MultiRangeBuffer virtualBuffer, ulong address, ulong size)
+        {
+            // Broadcast data to all ranges of the virtual buffer that are contained inside this buffer.
+
+            ulong lastOffset = 0;
+
+            while (virtualBuffer.TryGetPhysicalOffset(this, lastOffset, out ulong srcOffset, out ulong dstOffset, out ulong copySize))
+            {
+                ulong innerOffset = address - Address;
+                ulong innerEndOffset = (address + size) - Address;
+
+                lastOffset = dstOffset + copySize;
+
+                // Clamp range to the specified range.
+                ulong copySrcOffset = Math.Max(srcOffset, innerOffset);
+                ulong copySrcEndOffset = Math.Min(innerEndOffset, srcOffset + copySize);
+
+                if (copySrcEndOffset > copySrcOffset)
+                {
+                    copySize = copySrcEndOffset - copySrcOffset;
+                    dstOffset += copySrcOffset - srcOffset;
+                    srcOffset = copySrcOffset;
+
+                    _context.Renderer.Pipeline.CopyBuffer(Handle, virtualBuffer.Handle, (int)srcOffset, (int)dstOffset, (int)copySize);
+                }
+            }
+        }
+
+        /// <summary>
         /// Increments the buffer reference count.
         /// </summary>
         public void IncrementReferenceCount()