/*++

Copyright (c) 1990-2003 Microsoft Corporation, All Rights Reserved

Module Name:

    ramdisk.h

Abstract:

    This file includes data declarations for the Ram Disk driver for NT.

Environment:

    Kernel mode only.

--*/

#ifndef _RAMDISK_H_
#define _RAMDISK_H_

#pragma warning(disable:4201)  // nameless struct/union warning

#include <ntddk.h>
#include <ntdddisk.h>

#pragma warning(default:4201)

#include <wdf.h>
#define NTSTRSAFE_LIB
#include <ntstrsafe.h>
#include "forward_progress.h"

#define NT_DEVICE_NAME                  L"\\Device\\Ramdisk"
#define DOS_DEVICE_NAME                 L"\\DosDevices\\"

#define RAMDISK_TAG                     'DmaR'  // "RamD"
#define DOS_DEVNAME_LENGTH              (sizeof(DOS_DEVICE_NAME)+sizeof(WCHAR)*10)
#define DRIVE_LETTER_LENGTH             (sizeof(WCHAR)*10)

#define DRIVE_LETTER_BUFFER_SIZE        10
#define DOS_DEVNAME_BUFFER_SIZE         (sizeof(DOS_DEVICE_NAME) / 2) + 10

#define RAMDISK_MEDIA_TYPE              0xF8
#define DIR_ENTRIES_PER_SECTOR          16

#define DEFAULT_DISK_SIZE               (1024*1024)     // 1 MB
#define DEFAULT_ROOT_DIR_ENTRIES        512
#define DEFAULT_SECTORS_PER_CLUSTER     2
#define DEFAULT_DRIVE_LETTER            L"Z:"

typedef struct _DISK_INFO {
    ULONG   DiskSize;           // Ramdisk size in bytes
    ULONG   RootDirEntries;     // No. of root directory entries
    ULONG   SectorsPerCluster;  // Sectors per cluster
    UNICODE_STRING DriveLetter; // Drive letter to be used
} DISK_INFO, *PDISK_INFO;

typedef struct _DEVICE_EXTENSION {
    PUCHAR              DiskImage;                  // Pointer to beginning of disk image
    DISK_GEOMETRY       DiskGeometry;               // Drive parameters built by Ramdisk
    DISK_INFO           DiskRegInfo;                // Disk parameters from the registry
    UNICODE_STRING      SymbolicLink;               // Dos symbolic name; Drive letter
    WCHAR               DriveLetterBuffer[DRIVE_LETTER_BUFFER_SIZE];
    WCHAR               DosDeviceNameBuffer[DOS_DEVNAME_BUFFER_SIZE];
} DEVICE_EXTENSION, *PDEVICE_EXTENSION;

WDF_DECLARE_CONTEXT_TYPE_WITH_NAME(DEVICE_EXTENSION, DeviceGetExtension)

typedef struct _QUEUE_EXTENSION {
    PDEVICE_EXTENSION DeviceExtension;
} QUEUE_EXTENSION, *PQUEUE_EXTENSION;

WDF_DECLARE_CONTEXT_TYPE_WITH_NAME(QUEUE_EXTENSION, QueueGetExtension)

#pragma pack(1)

typedef struct  _BOOT_SECTOR
{
    UCHAR       bsJump[3];          // x86 jmp instruction, checked by FS
    CCHAR       bsOemName[8];       // OEM name of formatter
    USHORT      bsBytesPerSec;      // Bytes per Sector
    UCHAR       bsSecPerClus;       // Sectors per Cluster
    USHORT      bsResSectors;       // Reserved Sectors
    UCHAR       bsFATs;             // Number of FATs - we always use 1
    USHORT      bsRootDirEnts;      // Number of Root Dir Entries
    USHORT      bsSectors;          // Number of Sectors
    UCHAR       bsMedia;            // Media type - we use RAMDISK_MEDIA_TYPE
    USHORT      bsFATsecs;          // Number of FAT sectors
    USHORT      bsSecPerTrack;      // Sectors per Track - we use 32
    USHORT      bsHeads;            // Number of Heads - we use 2
    ULONG       bsHiddenSecs;       // Hidden Sectors - we set to 0
    ULONG       bsHugeSectors;      // Number of Sectors if > 32 MB size
    UCHAR       bsDriveNumber;      // Drive Number - not used
    UCHAR       bsReserved1;        // Reserved
    UCHAR       bsBootSignature;    // New Format Boot Signature - 0x29
    ULONG       bsVolumeID;         // VolumeID - set to 0x12345678
    CCHAR       bsLabel[11];        // Label - set to RamDisk
    CCHAR       bsFileSystemType[8];// File System Type - FAT12 or FAT16
    CCHAR       bsReserved2[448];   // Reserved
    UCHAR       bsSig2[2];          // Originial Boot Signature - 0x55, 0xAA
}   BOOT_SECTOR, *PBOOT_SECTOR;

typedef struct  _DIR_ENTRY
{
    UCHAR       deName[8];          // File Name
    UCHAR       deExtension[3];     // File Extension
    UCHAR       deAttributes;       // File Attributes
    UCHAR       deReserved;         // Reserved
    USHORT      deTime;             // File Time
    USHORT      deDate;             // File Date
    USHORT      deStartCluster;     // First Cluster of file
    ULONG       deFileSize;         // File Length
}   DIR_ENTRY, *PDIR_ENTRY;

#pragma pack()

//
// Directory Entry Attributes
//

#define DIR_ATTR_READONLY   0x01
#define DIR_ATTR_HIDDEN     0x02
#define DIR_ATTR_SYSTEM     0x04
#define DIR_ATTR_VOLUME     0x08
#define DIR_ATTR_DIRECTORY  0x10
#define DIR_ATTR_ARCHIVE    0x20

DRIVER_INITIALIZE DriverEntry;

#if KMDF_VERSION_MINOR >= 7

EVT_WDF_DRIVER_DEVICE_ADD RamDiskEvtDeviceAdd;
EVT_WDF_DEVICE_CONTEXT_CLEANUP RamDiskEvtDeviceContextCleanup;
EVT_WDF_IO_QUEUE_IO_READ RamDiskEvtIoRead;
EVT_WDF_IO_QUEUE_IO_WRITE RamDiskEvtIoWrite;
EVT_WDF_IO_QUEUE_IO_DEVICE_CONTROL RamDiskEvtIoDeviceControl;

#else

NTSTATUS
RamDiskEvtDeviceAdd(
    IN WDFDRIVER Driver,
    IN PWDFDEVICE_INIT DeviceInit
    );

VOID
RamDiskEvtDeviceContextCleanup(
    IN WDFOBJECT Device
    );

VOID
RamDiskEvtIoRead(
    IN WDFQUEUE Queue,
    IN WDFREQUEST Request,
    IN size_t Length
    );

VOID
RamDiskEvtIoWrite(
    IN WDFQUEUE Queue,
    IN WDFREQUEST Request,
    IN size_t Length
    );

VOID
RamDiskEvtIoDeviceControl(
    IN WDFQUEUE Queue,
    IN WDFREQUEST Request,
    IN size_t OutputBufferLength,
    IN size_t InputBufferLength,
    IN ULONG IoControlCode
    );

#endif

VOID
RamDiskQueryDiskRegParameters(
    _In_ PWSTR RegistryPath,
    _In_ PDISK_INFO DiskRegInfo
    );

NTSTATUS
RamDiskFormatDisk(
    IN PDEVICE_EXTENSION DeviceExtension
    );

BOOLEAN
RamDiskCheckParameters(
    IN PDEVICE_EXTENSION devExt,
    IN LARGE_INTEGER ByteOffset,
    IN size_t Length
    );

#endif    // _RAMDISK_H_