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   UINT8  PhysicalBlockExp; // # of logical blocks per physical block (log2)
  30   UINT8  AlignmentOffset;  // offset of first aligned logical block
  31   UINT16 MinIoSize;        // suggested minimum I/O size in blocks
  32   UINT32 OptIoSize;        // optimal (suggested maximum) I/O size in blocks
  33 } VIRTIO_BLK_TOPOLOGY;
  34
  35 typedef struct {
  36   UINT64              Capacity;
  37   UINT32              SizeMax;
  38   UINT32              SegMax;
  39   UINT16              Cylinders;
  40   UINT8               Heads;
  41   UINT8               Sectors;
  42   UINT32              BlkSize;
  43   VIRTIO_BLK_TOPOLOGY Topology;
  44 } VIRTIO_BLK_CONFIG;
  45 #pragma pack()
  46
  47 #define OFFSET_OF_VBLK(Field) OFFSET_OF (VIRTIO_BLK_CONFIG, Field)
  48 #define SIZE_OF_VBLK(Field)   (sizeof ((VIRTIO_BLK_CONFIG *) 0)->Field)
  49
  50 #define VIRTIO_BLK_F_BARRIER  BIT0
  51 #define VIRTIO_BLK_F_SIZE_MAX BIT1
  52 #define VIRTIO_BLK_F_SEG_MAX  BIT2
  53 #define VIRTIO_BLK_F_GEOMETRY BIT4
  54 #define VIRTIO_BLK_F_RO       BIT5
  55 #define VIRTIO_BLK_F_BLK_SIZE BIT6  // treated as "logical block size" in
  56                                     // practice; actual host side
  57                                     // implementation negotiates "optimal"
  58                                     // block size separately, via
  59                                     // VIRTIO_BLK_F_TOPOLOGY
  60 #define VIRTIO_BLK_F_SCSI     BIT7
  61 #define VIRTIO_BLK_F_FLUSH    BIT9  // identical to "write cache enabled"
  62 #define VIRTIO_BLK_F_TOPOLOGY BIT10 // information on optimal I/O alignment
  63
  64 //
  65 // We keep the status byte separate from the rest of the virtio-blk request
  66 // header. See description of historical scattering at the end of Appendix D:
  67 // we're going to put the status byte in a separate VRING_DESC.
  68 //
  69 #pragma pack(1)
  70 typedef struct {
  71   UINT32 Type;
  72   UINT32 IoPrio;
  73   UINT64 Sector;
  74 } VIRTIO_BLK_REQ;
  75 #pragma pack()
  76
  77 #define VIRTIO_BLK_T_IN           0x00000000
  78 #define VIRTIO_BLK_T_OUT          0x00000001
  79 #define VIRTIO_BLK_T_SCSI_CMD     0x00000002
  80 #define VIRTIO_BLK_T_SCSI_CMD_OUT 0x00000003
  81 #define VIRTIO_BLK_T_FLUSH        0x00000004
  82 #define VIRTIO_BLK_T_FLUSH_OUT    0x00000005
  83 #define VIRTIO_BLK_T_BARRIER      BIT31
  84
  85 #define VIRTIO_BLK_S_OK           0x00
  86 #define VIRTIO_BLK_S_IOERR        0x01
  87 #define VIRTIO_BLK_S_UNSUPP       0x02
  88
  89 #endif // _VIRTIO_BLK_H_