// Public nt-lite DMA declarations.

#pragma once

#include <stddef.h>
#include <stdint.h>
#include <ntlite/status.h>

struct DEVICE_OBJECT;
struct PROCESS;
typedef struct IO_DMA_ADAPTER IO_DMA_ADAPTER;
typedef struct IO_DMA_BUFFER IO_DMA_BUFFER;
typedef struct IO_DMA_MAPPING IO_DMA_MAPPING;
typedef struct MM_PINNED_MEMORY MM_PINNED_MEMORY;

typedef enum IO_DMA_DIRECTION {
    IoDmaToDevice = 1,
    IoDmaFromDevice,
    IoDmaBidirectional
} IO_DMA_DIRECTION;

// Fails a streaming mapping instead of allocating a bounce buffer.
#define IO_DMA_MAP_NO_BOUNCE 0x00000001u

// Describes immutable constraints shared by one device adapter. Address,
// alignment, and boundary limits apply to common buffers. Segment limits apply
// to streaming mappings. Zero selects the unconstrained default for each field.
typedef struct IO_DMA_REQUIREMENTS {
    uint64_t MaximumDeviceAddress;
    size_t Alignment;
    size_t Boundary;
    size_t MaximumSegmentLength;
    uint32_t MaximumSegments;
} IO_DMA_REQUIREMENTS;

// Describes one device-visible span in a streaming mapping.
typedef struct IO_DMA_SEGMENT {
    uint64_t DeviceAddress;
    size_t Length;
} IO_DMA_SEGMENT;

// Reports cumulative activity and live ownership for validation.
typedef struct IO_DMA_STATS {
    uint64_t AdaptersCreated;
    uint64_t AdaptersDestroyed;
    uint64_t AdaptersInUse;
    uint64_t CommonBuffersAllocated;
    uint64_t CommonBuffersFreed;
    uint64_t CommonBuffersInUse;
    uint64_t CommonBufferBytesInUse;
    uint64_t PinnedKernelRanges;
    uint64_t PinnedUserRanges;
    uint64_t PinnedRangesReleased;
    uint64_t PinnedRangesInUse;
    uint64_t PinnedPagesInUse;
    uint64_t StreamingMappings;
    uint64_t StreamingMappingsUnmapped;
    uint64_t StreamingMappingsInUse;
    uint64_t DirectMappings;
    uint64_t BounceMappings;
    uint64_t BounceBytesCopiedToDevice;
    uint64_t BounceBytesCopiedToCpu;
    uint64_t FailedAllocations;
    uint64_t FailedMappings;
} IO_DMA_STATS;


__declspec(dllexport) KSTATUS IoDmaGetAdapter(struct DEVICE_OBJECT* device, const IO_DMA_REQUIREMENTS* requirements, IO_DMA_ADAPTER** outAdapter);
__declspec(dllexport) void IoDmaPutAdapter(IO_DMA_ADAPTER* adapter);
__declspec(dllexport) KSTATUS IoDmaAllocateCommonBuffer(IO_DMA_ADAPTER* adapter, size_t size, size_t alignment, IO_DMA_BUFFER** outBuffer);
__declspec(dllexport) void IoDmaFreeCommonBuffer(IO_DMA_BUFFER* buffer);
__declspec(dllexport) void* IoDmaGetCommonBufferAddress(const IO_DMA_BUFFER* buffer);
__declspec(dllexport) uint64_t IoDmaGetCommonBufferDeviceAddress(const IO_DMA_BUFFER* buffer);
__declspec(dllexport) size_t IoDmaGetCommonBufferSize(const IO_DMA_BUFFER* buffer);
__declspec(dllexport) KSTATUS IoDmaPinKernelMemory(void* address, size_t size, IO_DMA_DIRECTION direction, MM_PINNED_MEMORY** outMemory);
__declspec(dllexport) KSTATUS IoDmaPinUserMemory(struct PROCESS* process, void* address, size_t size, IO_DMA_DIRECTION direction, MM_PINNED_MEMORY** outMemory);
__declspec(dllexport) void IoDmaUnpinMemory(MM_PINNED_MEMORY* memory);
__declspec(dllexport) KSTATUS IoDmaMapPinnedMemory(IO_DMA_ADAPTER* adapter, MM_PINNED_MEMORY* memory, size_t offset, size_t length, IO_DMA_DIRECTION direction, uint32_t flags, IO_DMA_MAPPING** outMapping);
__declspec(dllexport) void IoDmaUnmapMemory(IO_DMA_MAPPING* mapping);
__declspec(dllexport) KSTATUS IoDmaSynchronizeForDevice(IO_DMA_MAPPING* mapping);
__declspec(dllexport) KSTATUS IoDmaSynchronizeForCpu(IO_DMA_MAPPING* mapping);
__declspec(dllexport) uint32_t IoDmaGetSegmentCount(const IO_DMA_MAPPING* mapping);
__declspec(dllexport) const IO_DMA_SEGMENT* IoDmaGetSegments(const IO_DMA_MAPPING* mapping);
__declspec(dllexport) void IoDmaQueryStats(IO_DMA_STATS* outStats);