#pragma once
// io_driver.h - definitive kernel driver/device I/O model
//
// Disk controllers register DEVICE_OBJECTs.  IRPs are submitted only through
// IoCallDriver()/IoSubmitIrp(); drivers complete accepted IRPs by calling
// IoCompleteRequest().  There is no legacy DISK_DRIVER submit table.

#include <stdint.h>
#include <stdbool.h>
#include <stddef.h>
#include <ke_status.h>

typedef struct HAL_API HAL_API;
typedef KSTATUS (*DRIVER_ENTRY_FN)(const HAL_API* hal);
typedef void    (*DRIVER_UNLOAD_FN)(void);

struct IRP;
typedef struct DRIVER_OBJECT DRIVER_OBJECT;
typedef struct DEVICE_OBJECT DEVICE_OBJECT;

typedef enum IO_MAJOR_FUNCTION {
    IRP_MJ_READ  = 0,
    IRP_MJ_WRITE = 1,
    IRP_MJ_DEVICE_CONTROL = 2,
    IRP_MJ_MAXIMUM_FUNCTION = 3,
} IO_MAJOR_FUNCTION;

typedef KSTATUS (*PDRIVER_DISPATCH)(DEVICE_OBJECT* device, struct IRP* irp);

struct DRIVER_OBJECT {
    const char*       Name;
    PDRIVER_DISPATCH  MajorFunction[IRP_MJ_MAXIMUM_FUNCTION];
    DRIVER_UNLOAD_FN  DriverUnload;
};

struct DEVICE_OBJECT {
    DRIVER_OBJECT* DriverObject;
    void*          DeviceExtension;
    uint32_t       Flags;
    uint32_t       AlignmentRequirement;
    uint64_t       SectorCount;
    uint8_t        DiskIndex;
};

#define DEVICE_OBJECT_DISK       0x00000001u
#define DEVICE_OBJECT_REMOVABLE  0x00000002u

__declspec(dllexport) KSTATUS IoCreateDevice(DRIVER_OBJECT* driver,
                                             size_t extensionSize,
                                             DEVICE_OBJECT** outDevice);
__declspec(dllexport) void    IoDeleteDevice(DEVICE_OBJECT* device);

__declspec(dllexport) KSTATUS IoRegisterDiskDevice(uint8_t driveIndex,
                                                   DEVICE_OBJECT* device);
__declspec(dllexport) DEVICE_OBJECT* IoGetDiskDevice(uint8_t driveIndex);
__declspec(dllexport) bool    IoDiskDevicePresent(uint8_t driveIndex);
__declspec(dllexport) uint64_t IoDiskSectorCount(uint8_t driveIndex);

__declspec(dllexport) KSTATUS IoCallDriver(DEVICE_OBJECT* device,
                                           struct IRP* irp);

__declspec(dllexport) KSTATUS IoReadDiskSectors(uint8_t driveIndex,
                                                uint64_t lba,
                                                uint32_t count,
                                                void* buffer);
__declspec(dllexport) KSTATUS IoWriteDiskSectors(uint8_t driveIndex,
                                                 uint64_t lba,
                                                 uint32_t count,
                                                 const void* buffer);