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ryujinx-final/Ryujinx.Graphics.Gpu/Memory/MemoryManager.cs

350 lines
No EOL
12 KiB
C#

namespace Ryujinx.Graphics.Gpu.Memory
{
/// <summary>
/// GPU memory manager.
/// </summary>
public class MemoryManager
{
private const ulong AddressSpaceSize = 1UL << 40;
public const ulong BadAddress = ulong.MaxValue;
private const int PtLvl0Bits = 14;
private const int PtLvl1Bits = 14;
public const int PtPageBits = 12;
private const ulong PtLvl0Size = 1UL << PtLvl0Bits;
private const ulong PtLvl1Size = 1UL << PtLvl1Bits;
public const ulong PageSize = 1UL << PtPageBits;
private const ulong PtLvl0Mask = PtLvl0Size - 1;
private const ulong PtLvl1Mask = PtLvl1Size - 1;
public const ulong PageMask = PageSize - 1;
private const int PtLvl0Bit = PtPageBits + PtLvl1Bits;
private const int PtLvl1Bit = PtPageBits;
private const ulong PteUnmapped = 0xffffffff_ffffffff;
private const ulong PteReserved = 0xffffffff_fffffffe;
private ulong[][] _pageTable;
/// <summary>
/// Creates a new instance of the GPU memory manager.
/// </summary>
public MemoryManager()
{
_pageTable = new ulong[PtLvl0Size][];
}
/// <summary>
/// Maps a given range of pages to the specified CPU virtual address.
/// All addresses and sizes must be page aligned.
/// </summary>
/// <param name="pa">CPU virtual address to map into</param>
/// <param name="va">GPU virtual address to be mapped</param>
/// <param name="size">Size in bytes of the mapping</param>
/// <returns>GPU virtual address of the mapping</returns>
public ulong Map(ulong pa, ulong va, ulong size)
{
lock (_pageTable)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
SetPte(va + offset, pa + offset);
}
}
return va;
}
/// <summary>
/// Maps a given range of pages to a allocated GPU virtual address.
/// The memory is automatically allocated by the memory manager.
/// </summary>
/// <param name="pa">CPU virtual address to map into</param>
/// <param name="size">Mapping size in bytes</param>
/// <returns>GPU virtual address where the range was mapped, or an all ones mask in case of failure</returns>
public ulong Map(ulong pa, ulong size)
{
lock (_pageTable)
{
ulong va = GetFreePosition(size);
if (va != PteUnmapped)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
SetPte(va + offset, pa + offset);
}
}
return va;
}
}
/// <summary>
/// Maps a given range of pages to a allocated GPU virtual address.
/// The memory is automatically allocated by the memory manager.
/// This also ensures that the mapping is always done in the first 4GB of GPU address space.
/// </summary>
/// <param name="pa">CPU virtual address to map into</param>
/// <param name="size">Mapping size in bytes</param>
/// <returns>GPU virtual address where the range was mapped, or an all ones mask in case of failure</returns>
public ulong MapLow(ulong pa, ulong size)
{
lock (_pageTable)
{
ulong va = GetFreePosition(size, 1, PageSize);
if (va != PteUnmapped && va <= uint.MaxValue && (va + size) <= uint.MaxValue)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
SetPte(va + offset, pa + offset);
}
}
else
{
va = PteUnmapped;
}
return va;
}
}
/// <summary>
/// Reserves memory at a fixed GPU memory location.
/// This prevents the reserved region from being used for memory allocation for map.
/// </summary>
/// <param name="va">GPU virtual address to reserve</param>
/// <param name="size">Reservation size in bytes</param>
/// <returns>GPU virtual address of the reservation, or an all ones mask in case of failure</returns>
public ulong ReserveFixed(ulong va, ulong size)
{
lock (_pageTable)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
if (IsPageInUse(va + offset))
{
return PteUnmapped;
}
}
for (ulong offset = 0; offset < size; offset += PageSize)
{
SetPte(va + offset, PteReserved);
}
}
return va;
}
/// <summary>
/// Reserves memory at any GPU memory location.
/// </summary>
/// <param name="size">Reservation size in bytes</param>
/// <param name="alignment">Reservation address alignment in bytes</param>
/// <returns>GPU virtual address of the reservation, or an all ones mask in case of failure</returns>
public ulong Reserve(ulong size, ulong alignment)
{
lock (_pageTable)
{
ulong address = GetFreePosition(size, alignment);
if (address != PteUnmapped)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
SetPte(address + offset, PteReserved);
}
}
return address;
}
}
/// <summary>
/// Frees memory that was previously allocated by a map or reserved.
/// </summary>
/// <param name="va">GPU virtual address to free</param>
/// <param name="size">Size in bytes of the region being freed</param>
public void Free(ulong va, ulong size)
{
lock (_pageTable)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
SetPte(va + offset, PteUnmapped);
}
}
}
/// <summary>
/// Gets the address of a unused (free) region of the specified size.
/// </summary>
/// <param name="size">Size of the region in bytes</param>
/// <param name="alignment">Required alignment of the region address in bytes</param>
/// <param name="start">Start address of the search on the address space</param>
/// <returns>GPU virtual address of the allocation, or an all ones mask in case of failure</returns>
private ulong GetFreePosition(ulong size, ulong alignment = 1, ulong start = 1UL << 32)
{
// Note: Address 0 is not considered valid by the driver,
// when 0 is returned it's considered a mapping error.
ulong address = start;
ulong freeSize = 0;
if (alignment == 0)
{
alignment = 1;
}
alignment = (alignment + PageMask) & ~PageMask;
while (address + freeSize < AddressSpaceSize)
{
if (!IsPageInUse(address + freeSize))
{
freeSize += PageSize;
if (freeSize >= size)
{
return address;
}
}
else
{
address += freeSize + PageSize;
freeSize = 0;
ulong remainder = address % alignment;
if (remainder != 0)
{
address = (address - remainder) + alignment;
}
}
}
return PteUnmapped;
}
/// <summary>
/// Gets the number of mapped or reserved pages on a given region.
/// </summary>
/// <param name="gpuVa">Start GPU virtual address of the region</param>
/// <returns>Mapped size in bytes of the specified region</returns>
internal ulong GetSubSize(ulong gpuVa)
{
ulong size = 0;
while (GetPte(gpuVa + size) != PteUnmapped)
{
size += PageSize;
}
return size;
}
/// <summary>
/// Translated a GPU virtual address to a CPU virtual address.
/// </summary>
/// <param name="gpuVa">GPU virtual address to be translated</param>
/// <returns>CPU virtual address</returns>
internal ulong Translate(ulong gpuVa)
{
ulong baseAddress = GetPte(gpuVa);
if (baseAddress == PteUnmapped || baseAddress == PteReserved)
{
return PteUnmapped;
}
return baseAddress + (gpuVa & PageMask);
}
/// <summary>
/// Checks if a given memory region is currently unmapped.
/// </summary>
/// <param name="gpuVa">Start GPU virtual address of the region</param>
/// <param name="size">Size in bytes of the region</param>
/// <returns>True if the region is unmapped (free), false otherwise</returns>
public bool IsRegionFree(ulong gpuVa, ulong size)
{
for (ulong offset = 0; offset < size; offset += PageSize)
{
if (IsPageInUse(gpuVa + offset))
{
return false;
}
}
return true;
}
/// <summary>
/// Checks if a given memory page is mapped or reserved.
/// </summary>
/// <param name="gpuVa">GPU virtual address of the page</param>
/// <returns>True if the page is mapped or reserved, false otherwise</returns>
private bool IsPageInUse(ulong gpuVa)
{
if (gpuVa >> PtLvl0Bits + PtLvl1Bits + PtPageBits != 0)
{
return false;
}
ulong l0 = (gpuVa >> PtLvl0Bit) & PtLvl0Mask;
ulong l1 = (gpuVa >> PtLvl1Bit) & PtLvl1Mask;
if (_pageTable[l0] == null)
{
return false;
}
return _pageTable[l0][l1] != PteUnmapped;
}
/// <summary>
/// Gets the Page Table entry for a given GPU virtual address.
/// </summary>
/// <param name="gpuVa">GPU virtual address</param>
/// <returns>Page table entry (CPU virtual address)</returns>
private ulong GetPte(ulong gpuVa)
{
ulong l0 = (gpuVa >> PtLvl0Bit) & PtLvl0Mask;
ulong l1 = (gpuVa >> PtLvl1Bit) & PtLvl1Mask;
if (_pageTable[l0] == null)
{
return PteUnmapped;
}
return _pageTable[l0][l1];
}
/// <summary>
/// Sets a Page Table entry at a given GPU virtual address.
/// </summary>
/// <param name="gpuVa">GPU virtual address</param>
/// <param name="pte">Page table entry (CPU virtual address)</param>
private void SetPte(ulong gpuVa, ulong pte)
{
ulong l0 = (gpuVa >> PtLvl0Bit) & PtLvl0Mask;
ulong l1 = (gpuVa >> PtLvl1Bit) & PtLvl1Mask;
if (_pageTable[l0] == null)
{
_pageTable[l0] = new ulong[PtLvl1Size];
for (ulong index = 0; index < PtLvl1Size; index++)
{
_pageTable[l0][index] = PteUnmapped;
}
}
_pageTable[l0][l1] = pte;
}
}
}