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   SPDX-License-Identifier: BSD-2-Clause-Patent
   9
  10 **/
  11
  12 #ifndef _VIRTIO_BLK_H_
  13 #define _VIRTIO_BLK_H_
  14
  15 #include <IndustryStandard/Virtio.h>
  16
  17 //
  18 // virtio-0.9.5, Appendix D: Block Device
  19 //
  20 #pragma pack(1)
  21 typedef struct {
  22   UINT8     PhysicalBlockExp; // # of logical blocks per physical block (log2)
  23   UINT8     AlignmentOffset;  // offset of first aligned logical block
  24   UINT16    MinIoSize;        // suggested minimum I/O size in blocks
  25   UINT32    OptIoSize;        // optimal (suggested maximum) I/O size in blocks
  26 } VIRTIO_BLK_TOPOLOGY;
  27
  28 typedef struct {
  29   UINT64                 Capacity;
  30   UINT32                 SizeMax;
  31   UINT32                 SegMax;
  32   UINT16                 Cylinders;
  33   UINT8                  Heads;
  34   UINT8                  Sectors;
  35   UINT32                 BlkSize;
  36   VIRTIO_BLK_TOPOLOGY    Topology;
  37 } VIRTIO_BLK_CONFIG;
  38 #pragma pack()
  39
  40 #define OFFSET_OF_VBLK(Field)  OFFSET_OF (VIRTIO_BLK_CONFIG, Field)
  41 #define SIZE_OF_VBLK(Field)    (sizeof ((VIRTIO_BLK_CONFIG *) 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
  50                                     // implementation negotiates "optimal"
  51                                     // block size separately, via
  52                                     // VIRTIO_BLK_F_TOPOLOGY
  53 #define VIRTIO_BLK_F_SCSI      BIT7
  54 #define VIRTIO_BLK_F_FLUSH     BIT9  // identical to "write cache enabled"
  55 #define VIRTIO_BLK_F_TOPOLOGY  BIT10 // information on optimal I/O alignment
  56
  57 //
  58 // We keep the status byte separate from the rest of the virtio-blk request
  59 // header. See description of historical scattering at the end of Appendix D:
  60 // we're going to put the status byte in a separate VRING_DESC.
  61 //
  62 #pragma pack(1)
  63 typedef struct {
  64   UINT32    Type;
  65   UINT32    IoPrio;
  66   UINT64    Sector;
  67 } VIRTIO_BLK_REQ;
  68 #pragma pack()
  69
  70 #define VIRTIO_BLK_T_IN            0x00000000
  71 #define VIRTIO_BLK_T_OUT           0x00000001
  72 #define VIRTIO_BLK_T_SCSI_CMD      0x00000002
  73 #define VIRTIO_BLK_T_SCSI_CMD_OUT  0x00000003
  74 #define VIRTIO_BLK_T_FLUSH         0x00000004
  75 #define VIRTIO_BLK_T_FLUSH_OUT     0x00000005
  76 #define VIRTIO_BLK_T_BARRIER       BIT31
  77
  78 #define VIRTIO_BLK_S_OK      0x00
  79 #define VIRTIO_BLK_S_IOERR   0x01
  80 #define VIRTIO_BLK_S_UNSUPP  0x02
  81
  82 #endif // _VIRTIO_BLK_H_