OvmfPkg/Include/IndustryStandard/VirtioBlk.h

   1 /** @file
   2
   3   Virtio Block Device specific type and macro definitions corresponding to the
   4   virtio-0.9.5 specification.
   5
   6   Copyright (C) 2012, Red Hat, Inc.
   7
   8   This program and the accompanying materials are licensed and made available
   9   under the terms and conditions of the BSD License which accompanies this
  10   distribution. The full text of the license may be found at
  11   http://opensource.org/licenses/bsd-license.php
  12
  13   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
  14   WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  15
  16 **/
  17
  18 #ifndef _VIRTIO_BLK_H_
  19 #define _VIRTIO_BLK_H_
  20
  21 #include <IndustryStandard/Virtio.h>
  22
  23
  24 //
  25 // virtio-0.9.5, Appendix D: Block Device
  26 //
  27 #pragma pack(1)
  28 typedef struct {
  29   VIRTIO_HDR Generic;
  30   UINT64     VhdrCapacity;
  31   UINT32     VhdrSizeMax;
  32   UINT32     VhdrSegMax;
  33   UINT16     VhdrCylinders;
  34   UINT8      VhdrHeads;
  35   UINT8      VhdrSectors;
  36   UINT32     VhdrBlkSize;
  37 } VBLK_HDR;
  38 #pragma pack()
  39
  40 #define OFFSET_OF_VBLK(Field) OFFSET_OF (VBLK_HDR, Field)
  41 #define SIZE_OF_VBLK(Field)   (sizeof ((VBLK_HDR *) 0)->Field)
  42
  43 #define VIRTIO_BLK_F_BARRIER  BIT0
  44 #define VIRTIO_BLK_F_SIZE_MAX BIT1
  45 #define VIRTIO_BLK_F_SEG_MAX  BIT2
  46 #define VIRTIO_BLK_F_GEOMETRY BIT4
  47 #define VIRTIO_BLK_F_RO       BIT5
  48 #define VIRTIO_BLK_F_BLK_SIZE BIT6 // treated as "logical block size" in
  49                                    // practice; actual host side implementation
  50                                    // negotiates "optimal" block size
  51                                    // separately
  52 #define VIRTIO_BLK_F_SCSI     BIT7
  53 #define VIRTIO_BLK_F_FLUSH    BIT9 // identical to "write cache enabled"
  54
  55 //
  56 // We keep the status byte separate from the rest of the virtio-blk request
  57 // header. See description of historical scattering at the end of Appendix D:
  58 // we're going to put the status byte in a separate VRING_DESC.
  59 //
  60 #pragma pack(1)
  61 typedef struct {
  62   UINT32 Type;
  63   UINT32 IoPrio;
  64   UINT64 Sector;
  65 } VIRTIO_BLK_REQ;
  66 #pragma pack()
  67
  68 #define VIRTIO_BLK_T_IN           0x00000000
  69 #define VIRTIO_BLK_T_OUT          0x00000001
  70 #define VIRTIO_BLK_T_SCSI_CMD     0x00000002
  71 #define VIRTIO_BLK_T_SCSI_CMD_OUT 0x00000003
  72 #define VIRTIO_BLK_T_FLUSH        0x00000004
  73 #define VIRTIO_BLK_T_FLUSH_OUT    0x00000005
  74 #define VIRTIO_BLK_T_BARRIER      BIT31
  75
  76 #define VIRTIO_BLK_S_OK           0x00
  77 #define VIRTIO_BLK_S_IOERR        0x01
  78 #define VIRTIO_BLK_S_UNSUPP       0x02
  79
  80 #endif // _VIRTIO_BLK_H_