ryujinx-mirror/Ryujinx.Cpu/MemoryManager.cs

608 lines
19 KiB
C#

using ARMeilleure.Memory;
using Ryujinx.Cpu.Tracking;
using Ryujinx.Memory;
using Ryujinx.Memory.Range;
using Ryujinx.Memory.Tracking;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Threading;
namespace Ryujinx.Cpu
{
/// <summary>
/// Represents a CPU memory manager.
/// </summary>
public sealed class MemoryManager : MemoryManagerBase, IMemoryManager, IVirtualMemoryManagerTracked, IWritableBlock
{
public const int PageBits = 12;
public const int PageSize = 1 << PageBits;
public const int PageMask = PageSize - 1;
private const int PteSize = 8;
private const int PointerTagBit = 62;
private readonly InvalidAccessHandler _invalidAccessHandler;
/// <summary>
/// Address space width in bits.
/// </summary>
public int AddressSpaceBits { get; }
private readonly ulong _addressSpaceSize;
private readonly MemoryBlock _pageTable;
/// <summary>
/// Page table base pointer.
/// </summary>
public IntPtr PageTablePointer => _pageTable.Pointer;
public MemoryManagerType Type => MemoryManagerType.SoftwarePageTable;
public MemoryTracking Tracking { get; }
public event Action<ulong, ulong> UnmapEvent;
/// <summary>
/// Creates a new instance of the memory manager.
/// </summary>
/// <param name="addressSpaceSize">Size of the address space</param>
/// <param name="invalidAccessHandler">Optional function to handle invalid memory accesses</param>
public MemoryManager(ulong addressSpaceSize, InvalidAccessHandler invalidAccessHandler = null)
{
_invalidAccessHandler = invalidAccessHandler;
ulong asSize = PageSize;
int asBits = PageBits;
while (asSize < addressSpaceSize)
{
asSize <<= 1;
asBits++;
}
AddressSpaceBits = asBits;
_addressSpaceSize = asSize;
_pageTable = new MemoryBlock((asSize / PageSize) * PteSize);
Tracking = new MemoryTracking(this, PageSize);
}
/// <inheritdoc/>
public void Map(ulong va, nuint hostAddress, ulong size)
{
AssertValidAddressAndSize(va, size);
ulong remainingSize = size;
ulong oVa = va;
while (remainingSize != 0)
{
_pageTable.Write((va / PageSize) * PteSize, hostAddress);
va += PageSize;
hostAddress += PageSize;
remainingSize -= PageSize;
}
Tracking.Map(oVa, size);
}
/// <inheritdoc/>
public void Unmap(ulong va, ulong size)
{
// If size is 0, there's nothing to unmap, just exit early.
if (size == 0)
{
return;
}
AssertValidAddressAndSize(va, size);
UnmapEvent?.Invoke(va, size);
Tracking.Unmap(va, size);
ulong remainingSize = size;
while (remainingSize != 0)
{
_pageTable.Write((va / PageSize) * PteSize, (nuint)0);
va += PageSize;
remainingSize -= PageSize;
}
}
/// <inheritdoc/>
public T Read<T>(ulong va) where T : unmanaged
{
return MemoryMarshal.Cast<byte, T>(GetSpan(va, Unsafe.SizeOf<T>()))[0];
}
/// <inheritdoc/>
public T ReadTracked<T>(ulong va) where T : unmanaged
{
SignalMemoryTracking(va, (ulong)Unsafe.SizeOf<T>(), false);
return MemoryMarshal.Cast<byte, T>(GetSpan(va, Unsafe.SizeOf<T>()))[0];
}
/// <inheritdoc/>
public void Read(ulong va, Span<byte> data)
{
ReadImpl(va, data);
}
/// <inheritdoc/>
public void Write<T>(ulong va, T value) where T : unmanaged
{
Write(va, MemoryMarshal.Cast<T, byte>(MemoryMarshal.CreateSpan(ref value, 1)));
}
/// <inheritdoc/>
public void Write(ulong va, ReadOnlySpan<byte> data)
{
if (data.Length == 0)
{
return;
}
SignalMemoryTracking(va, (ulong)data.Length, true);
WriteImpl(va, data);
}
/// <inheritdoc/>
public void WriteUntracked(ulong va, ReadOnlySpan<byte> data)
{
if (data.Length == 0)
{
return;
}
WriteImpl(va, data);
}
/// <summary>
/// Writes data to CPU mapped memory.
/// </summary>
/// <param name="va">Virtual address to write the data into</param>
/// <param name="data">Data to be written</param>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private void WriteImpl(ulong va, ReadOnlySpan<byte> data)
{
try
{
AssertValidAddressAndSize(va, (ulong)data.Length);
if (IsContiguousAndMapped(va, data.Length))
{
data.CopyTo(GetHostSpanContiguous(va, data.Length));
}
else
{
int offset = 0, size;
if ((va & PageMask) != 0)
{
size = Math.Min(data.Length, PageSize - (int)(va & PageMask));
data.Slice(0, size).CopyTo(GetHostSpanContiguous(va, size));
offset += size;
}
for (; offset < data.Length; offset += size)
{
size = Math.Min(data.Length - offset, PageSize);
data.Slice(offset, size).CopyTo(GetHostSpanContiguous(va + (ulong)offset, size));
}
}
}
catch (InvalidMemoryRegionException)
{
if (_invalidAccessHandler == null || !_invalidAccessHandler(va))
{
throw;
}
}
}
/// <inheritdoc/>
public ReadOnlySpan<byte> GetSpan(ulong va, int size, bool tracked = false)
{
if (size == 0)
{
return ReadOnlySpan<byte>.Empty;
}
if (tracked)
{
SignalMemoryTracking(va, (ulong)size, false);
}
if (IsContiguousAndMapped(va, size))
{
return GetHostSpanContiguous(va, size);
}
else
{
Span<byte> data = new byte[size];
ReadImpl(va, data);
return data;
}
}
/// <inheritdoc/>
public unsafe WritableRegion GetWritableRegion(ulong va, int size, bool tracked = false)
{
if (size == 0)
{
return new WritableRegion(null, va, Memory<byte>.Empty);
}
if (IsContiguousAndMapped(va, size))
{
if (tracked)
{
SignalMemoryTracking(va, (ulong)size, true);
}
return new WritableRegion(null, va, new NativeMemoryManager<byte>((byte*)GetHostAddress(va), size).Memory);
}
else
{
Memory<byte> memory = new byte[size];
GetSpan(va, size).CopyTo(memory.Span);
return new WritableRegion(this, va, memory, tracked);
}
}
/// <inheritdoc/>
public unsafe ref T GetRef<T>(ulong va) where T : unmanaged
{
if (!IsContiguous(va, Unsafe.SizeOf<T>()))
{
ThrowMemoryNotContiguous();
}
SignalMemoryTracking(va, (ulong)Unsafe.SizeOf<T>(), true);
return ref *(T*)GetHostAddress(va);
}
/// <summary>
/// Computes the number of pages in a virtual address range.
/// </summary>
/// <param name="va">Virtual address of the range</param>
/// <param name="size">Size of the range</param>
/// <param name="startVa">The virtual address of the beginning of the first page</param>
/// <remarks>This function does not differentiate between allocated and unallocated pages.</remarks>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private int GetPagesCount(ulong va, uint size, out ulong startVa)
{
// WARNING: Always check if ulong does not overflow during the operations.
startVa = va & ~(ulong)PageMask;
ulong vaSpan = (va - startVa + size + PageMask) & ~(ulong)PageMask;
return (int)(vaSpan / PageSize);
}
private void ThrowMemoryNotContiguous() => throw new MemoryNotContiguousException();
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private bool IsContiguousAndMapped(ulong va, int size) => IsContiguous(va, size) && IsMapped(va);
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private bool IsContiguous(ulong va, int size)
{
if (!ValidateAddress(va) || !ValidateAddressAndSize(va, (ulong)size))
{
return false;
}
int pages = GetPagesCount(va, (uint)size, out va);
for (int page = 0; page < pages - 1; page++)
{
if (!ValidateAddress(va + PageSize))
{
return false;
}
if (GetHostAddress(va) + PageSize != GetHostAddress(va + PageSize))
{
return false;
}
va += PageSize;
}
return true;
}
/// <inheritdoc/>
public IEnumerable<HostMemoryRange> GetPhysicalRegions(ulong va, ulong size)
{
if (size == 0)
{
return Enumerable.Empty<HostMemoryRange>();
}
if (!ValidateAddress(va) || !ValidateAddressAndSize(va, size))
{
return null;
}
int pages = GetPagesCount(va, (uint)size, out va);
var regions = new List<HostMemoryRange>();
nuint regionStart = GetHostAddress(va);
ulong regionSize = PageSize;
for (int page = 0; page < pages - 1; page++)
{
if (!ValidateAddress(va + PageSize))
{
return null;
}
nuint newHostAddress = GetHostAddress(va + PageSize);
if (GetHostAddress(va) + PageSize != newHostAddress)
{
regions.Add(new HostMemoryRange(regionStart, regionSize));
regionStart = newHostAddress;
regionSize = 0;
}
va += PageSize;
regionSize += PageSize;
}
regions.Add(new HostMemoryRange(regionStart, regionSize));
return regions;
}
private void ReadImpl(ulong va, Span<byte> data)
{
if (data.Length == 0)
{
return;
}
try
{
AssertValidAddressAndSize(va, (ulong)data.Length);
int offset = 0, size;
if ((va & PageMask) != 0)
{
size = Math.Min(data.Length, PageSize - (int)(va & PageMask));
GetHostSpanContiguous(va, size).CopyTo(data.Slice(0, size));
offset += size;
}
for (; offset < data.Length; offset += size)
{
size = Math.Min(data.Length - offset, PageSize);
GetHostSpanContiguous(va + (ulong)offset, size).CopyTo(data.Slice(offset, size));
}
}
catch (InvalidMemoryRegionException)
{
if (_invalidAccessHandler == null || !_invalidAccessHandler(va))
{
throw;
}
}
}
/// <inheritdoc/>
public bool IsRangeMapped(ulong va, ulong size)
{
if (size == 0UL)
{
return true;
}
if (!ValidateAddressAndSize(va, size))
{
return false;
}
int pages = GetPagesCount(va, (uint)size, out va);
for (int page = 0; page < pages; page++)
{
if (!IsMapped(va))
{
return false;
}
va += PageSize;
}
return true;
}
/// <inheritdoc/>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public bool IsMapped(ulong va)
{
if (!ValidateAddress(va))
{
return false;
}
return _pageTable.Read<nuint>((va / PageSize) * PteSize) != 0;
}
private bool ValidateAddress(ulong va)
{
return va < _addressSpaceSize;
}
/// <summary>
/// Checks if the combination of virtual address and size is part of the addressable space.
/// </summary>
/// <param name="va">Virtual address of the range</param>
/// <param name="size">Size of the range in bytes</param>
/// <returns>True if the combination of virtual address and size is part of the addressable space</returns>
private bool ValidateAddressAndSize(ulong va, ulong size)
{
ulong endVa = va + size;
return endVa >= va && endVa >= size && endVa <= _addressSpaceSize;
}
/// <summary>
/// Ensures the combination of virtual address and size is part of the addressable space.
/// </summary>
/// <param name="va">Virtual address of the range</param>
/// <param name="size">Size of the range in bytes</param>
/// <exception cref="InvalidMemoryRegionException">Throw when the memory region specified outside the addressable space</exception>
private void AssertValidAddressAndSize(ulong va, ulong size)
{
if (!ValidateAddressAndSize(va, size))
{
throw new InvalidMemoryRegionException($"va=0x{va:X16}, size=0x{size:X16}");
}
}
/// <summary>
/// Get a span representing the given virtual address and size range in host memory.
/// This function assumes that the requested virtual memory region is contiguous.
/// </summary>
/// <param name="va">Virtual address of the range</param>
/// <param name="size">Size of the range in bytes</param>
/// <returns>A span representing the given virtual range in host memory</returns>
/// <exception cref="InvalidMemoryRegionException">Throw when the base virtual address is not mapped</exception>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private unsafe Span<byte> GetHostSpanContiguous(ulong va, int size)
{
return new Span<byte>((void*)GetHostAddress(va), size);
}
/// <summary>
/// Get the host address for a given virtual address, using the page table.
/// </summary>
/// <param name="va">Virtual address</param>
/// <returns>The corresponding host address for the given virtual address</returns>
/// <exception cref="InvalidMemoryRegionException">Throw when the virtual address is not mapped</exception>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private nuint GetHostAddress(ulong va)
{
nuint pageBase = _pageTable.Read<nuint>((va / PageSize) * PteSize) & unchecked((nuint)0xffff_ffff_ffffUL);
if (pageBase == 0)
{
ThrowInvalidMemoryRegionException($"Not mapped: va=0x{va:X16}");
}
return pageBase + (nuint)(va & PageMask);
}
/// <inheritdoc/>
public void TrackingReprotect(ulong va, ulong size, MemoryPermission protection)
{
AssertValidAddressAndSize(va, size);
// Protection is inverted on software pages, since the default value is 0.
protection = (~protection) & MemoryPermission.ReadAndWrite;
long tag = protection switch
{
MemoryPermission.None => 0L,
MemoryPermission.Write => 2L << PointerTagBit,
_ => 3L << PointerTagBit
};
int pages = GetPagesCount(va, (uint)size, out va);
ulong pageStart = va >> PageBits;
long invTagMask = ~(0xffffL << 48);
for (int page = 0; page < pages; page++)
{
ref long pageRef = ref _pageTable.GetRef<long>(pageStart * PteSize);
long pte;
do
{
pte = Volatile.Read(ref pageRef);
}
while (pte != 0 && Interlocked.CompareExchange(ref pageRef, (pte & invTagMask) | tag, pte) != pte);
pageStart++;
}
}
/// <inheritdoc/>
public CpuRegionHandle BeginTracking(ulong address, ulong size)
{
return new CpuRegionHandle(Tracking.BeginTracking(address, size));
}
/// <inheritdoc/>
public CpuMultiRegionHandle BeginGranularTracking(ulong address, ulong size, IEnumerable<IRegionHandle> handles, ulong granularity)
{
return new CpuMultiRegionHandle(Tracking.BeginGranularTracking(address, size, handles, granularity));
}
/// <inheritdoc/>
public CpuSmartMultiRegionHandle BeginSmartGranularTracking(ulong address, ulong size, ulong granularity)
{
return new CpuSmartMultiRegionHandle(Tracking.BeginSmartGranularTracking(address, size, granularity));
}
/// <inheritdoc/>
public void SignalMemoryTracking(ulong va, ulong size, bool write)
{
AssertValidAddressAndSize(va, size);
// We emulate guard pages for software memory access. This makes for an easy transition to
// tracking using host guard pages in future, but also supporting platforms where this is not possible.
// Write tag includes read protection, since we don't have any read actions that aren't performed before write too.
long tag = (write ? 3L : 1L) << PointerTagBit;
int pages = GetPagesCount(va, (uint)size, out _);
ulong pageStart = va >> PageBits;
for (int page = 0; page < pages; page++)
{
ref long pageRef = ref _pageTable.GetRef<long>(pageStart * PteSize);
long pte;
pte = Volatile.Read(ref pageRef);
if ((pte & tag) != 0)
{
Tracking.VirtualMemoryEvent(va, size, write);
break;
}
pageStart++;
}
}
/// <summary>
/// Disposes of resources used by the memory manager.
/// </summary>
protected override void Destroy() => _pageTable.Dispose();
private void ThrowInvalidMemoryRegionException(string message) => throw new InvalidMemoryRegionException(message);
}
}