LXR uboot/drivers/virtio/virtio

   1/* SPDX-License-Identifier: BSD-3-Clause */
   2/*
   3 * Copyright (C) 2018, Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>
   4 * Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
   5 *
   6 * From Linux kernel include/uapi/linux/virtio_blk.h
   7 */
   8
   9#ifndef _LINUX_VIRTIO_BLK_H
  10#define _LINUX_VIRTIO_BLK_H
  11
  12/* Feature bits */
  13#define VIRTIO_BLK_F_SIZE_MAX   1       /* Indicates maximum segment size */
  14#define VIRTIO_BLK_F_SEG_MAX    2       /* Indicates maximum # of segments */
  15#define VIRTIO_BLK_F_GEOMETRY   4       /* Legacy geometry available */
  16#define VIRTIO_BLK_F_RO         5       /* Disk is read-only */
  17#define VIRTIO_BLK_F_BLK_SIZE   6       /* Block size of disk is available */
  18#define VIRTIO_BLK_F_TOPOLOGY   10      /* Topology information is available */
  19#define VIRTIO_BLK_F_MQ         12      /* Support more than one vq */
  20
  21/* Legacy feature bits */
  22#ifndef VIRTIO_BLK_NO_LEGACY
  23#define VIRTIO_BLK_F_BARRIER    0       /* Does host support barriers? */
  24#define VIRTIO_BLK_F_SCSI       7       /* Supports scsi command passthru */
  25#define VIRTIO_BLK_F_FLUSH      9       /* Flush command supported */
  26#define VIRTIO_BLK_F_CONFIG_WCE 11      /* Writeback mode available in config */
  27#ifndef __KERNEL__
  28/* Old (deprecated) name for VIRTIO_BLK_F_FLUSH */
  29#define VIRTIO_BLK_F_WCE        VIRTIO_BLK_F_FLUSH
  30#endif
  31#endif /* !VIRTIO_BLK_NO_LEGACY */
  32
  33#define VIRTIO_BLK_ID_BYTES     20      /* ID string length */
  34
  35struct __packed virtio_blk_config {
  36        /* The capacity (in 512-byte sectors) */
  37        __u64 capacity;
  38        /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */
  39        __u32 size_max;
  40        /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */
  41        __u32 seg_max;
  42        /* geometry of the device (if VIRTIO_BLK_F_GEOMETRY) */
  43        struct virtio_blk_geometry {
  44                __u16 cylinders;
  45                __u8 heads;
  46                __u8 sectors;
  47        } geometry;
  48
  49        /* block size of device (if VIRTIO_BLK_F_BLK_SIZE) */
  50        __u32 blk_size;
  51
  52        /* the next 4 entries are guarded by VIRTIO_BLK_F_TOPOLOGY */
  53        /* exponent for physical block per logical block */
  54        __u8 physical_block_exp;
  55        /* alignment offset in logical blocks */
  56        __u8 alignment_offset;
  57        /* minimum I/O size without performance penalty in logical blocks */
  58        __u16 min_io_size;
  59        /* optimal sustained I/O size in logical blocks */
  60        __u32 opt_io_size;
  61
  62        /* writeback mode (if VIRTIO_BLK_F_CONFIG_WCE) */
  63        __u8 wce;
  64        __u8 unused;
  65
  66        /* number of vqs, only available when VIRTIO_BLK_F_MQ is set */
  67        __u16 num_queues;
  68};
  69
  70/*
  71 * Command types
  72 *
  73 * Usage is a bit tricky as some bits are used as flags and some are not.
  74 *
  75 * Rules:
  76 *   VIRTIO_BLK_T_OUT may be combined with VIRTIO_BLK_T_SCSI_CMD or
  77 *   VIRTIO_BLK_T_BARRIER. VIRTIO_BLK_T_FLUSH is a command of its own
  78 *   and may not be combined with any of the other flags.
  79 */
  80
  81/* These two define direction */
  82#define VIRTIO_BLK_T_IN         0
  83#define VIRTIO_BLK_T_OUT        1
  84
  85#ifndef VIRTIO_BLK_NO_LEGACY
  86/* This bit says it's a scsi command, not an actual read or write */
  87#define VIRTIO_BLK_T_SCSI_CMD   2
  88#endif /* VIRTIO_BLK_NO_LEGACY */
  89
  90/* Cache flush command */
  91#define VIRTIO_BLK_T_FLUSH      4
  92
  93/* Get device ID command */
  94#define VIRTIO_BLK_T_GET_ID     8
  95
  96#ifndef VIRTIO_BLK_NO_LEGACY
  97/* Barrier before this op */
  98#define VIRTIO_BLK_T_BARRIER    0x80000000
  99#endif /* !VIRTIO_BLK_NO_LEGACY */
 100
 101/*
 102 * This comes first in the read scatter-gather list.
 103 * For legacy virtio, if VIRTIO_F_ANY_LAYOUT is not negotiated,
 104 * this is the first element of the read scatter-gather list.
 105 */
 106struct virtio_blk_outhdr {
 107        /* VIRTIO_BLK_T* */
 108        __virtio32 type;
 109        /* io priority */
 110        __virtio32 ioprio;
 111        /* Sector (ie. 512 byte offset) */
 112        __virtio64 sector;
 113};
 114
 115#ifndef VIRTIO_BLK_NO_LEGACY
 116struct virtio_scsi_inhdr {
 117        __virtio32 errors;
 118        __virtio32 data_len;
 119        __virtio32 sense_len;
 120        __virtio32 residual;
 121};
 122#endif /* !VIRTIO_BLK_NO_LEGACY */
 123
 124/* And this is the final byte of the write scatter-gather list */
 125#define VIRTIO_BLK_S_OK         0
 126#define VIRTIO_BLK_S_IOERR      1
 127#define VIRTIO_BLK_S_UNSUPP     2
 128
 129#endif /* _LINUX_VIRTIO_BLK_H */
 130