include/hw/virtio/virtio-blk.h

   1 /*
   2  * Virtio Block Device
   3  *
   4  * Copyright IBM, Corp. 2007
   5  *
   6  * Authors:
   7  *  Anthony Liguori   <aliguori@us.ibm.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2.  See
  10  * the COPYING file in the top-level directory.
  11  *
  12  */
  13
  14 #ifndef _QEMU_VIRTIO_BLK_H
  15 #define _QEMU_VIRTIO_BLK_H
  16
  17 #include "hw/virtio/virtio.h"
  18 #include "hw/block/block.h"
  19
  20 #define TYPE_VIRTIO_BLK "virtio-blk"
  21 #define VIRTIO_BLK(obj) \
  22         OBJECT_CHECK(VirtIOBlock, (obj), TYPE_VIRTIO_BLK)
  23
  24 /* from Linux's linux/virtio_blk.h */
  25
  26 /* The ID for virtio_block */
  27 #define VIRTIO_ID_BLOCK 2
  28
  29 /* Feature bits */
  30 #define VIRTIO_BLK_F_BARRIER    0       /* Does host support barriers? */
  31 #define VIRTIO_BLK_F_SIZE_MAX   1       /* Indicates maximum segment size */
  32 #define VIRTIO_BLK_F_SEG_MAX    2       /* Indicates maximum # of segments */
  33 #define VIRTIO_BLK_F_GEOMETRY   4       /* Indicates support of legacy geometry */
  34 #define VIRTIO_BLK_F_RO         5       /* Disk is read-only */
  35 #define VIRTIO_BLK_F_BLK_SIZE   6       /* Block size of disk is available*/
  36 #define VIRTIO_BLK_F_SCSI       7       /* Supports scsi command passthru */
  37 /* #define VIRTIO_BLK_F_IDENTIFY   8       ATA IDENTIFY supported, DEPRECATED */
  38 #define VIRTIO_BLK_F_WCE        9       /* write cache enabled */
  39 #define VIRTIO_BLK_F_TOPOLOGY   10      /* Topology information is available */
  40 #define VIRTIO_BLK_F_CONFIG_WCE 11      /* write cache configurable */
  41
  42 #define VIRTIO_BLK_ID_BYTES     20      /* ID string length */
  43
  44 struct virtio_blk_config
  45 {
  46     uint64_t capacity;
  47     uint32_t size_max;
  48     uint32_t seg_max;
  49     uint16_t cylinders;
  50     uint8_t heads;
  51     uint8_t sectors;
  52     uint32_t blk_size;
  53     uint8_t physical_block_exp;
  54     uint8_t alignment_offset;
  55     uint16_t min_io_size;
  56     uint32_t opt_io_size;
  57     uint8_t wce;
  58 } QEMU_PACKED;
  59
  60 /* These two define direction. */
  61 #define VIRTIO_BLK_T_IN         0
  62 #define VIRTIO_BLK_T_OUT        1
  63
  64 /* This bit says it's a scsi command, not an actual read or write. */
  65 #define VIRTIO_BLK_T_SCSI_CMD   2
  66
  67 /* Flush the volatile write cache */
  68 #define VIRTIO_BLK_T_FLUSH      4
  69
  70 /* return the device ID string */
  71 #define VIRTIO_BLK_T_GET_ID     8
  72
  73 /* Barrier before this op. */
  74 #define VIRTIO_BLK_T_BARRIER    0x80000000
  75
  76 /* This is the first element of the read scatter-gather list. */
  77 struct virtio_blk_outhdr
  78 {
  79     /* VIRTIO_BLK_T* */
  80     uint32_t type;
  81     /* io priority. */
  82     uint32_t ioprio;
  83     /* Sector (ie. 512 byte offset) */
  84     uint64_t sector;
  85 };
  86
  87 #define VIRTIO_BLK_S_OK         0
  88 #define VIRTIO_BLK_S_IOERR      1
  89 #define VIRTIO_BLK_S_UNSUPP     2
  90
  91 /* This is the last element of the write scatter-gather list */
  92 struct virtio_blk_inhdr
  93 {
  94     unsigned char status;
  95 };
  96
  97 /* SCSI pass-through header */
  98 struct virtio_scsi_inhdr
  99 {
 100     uint32_t errors;
 101     uint32_t data_len;
 102     uint32_t sense_len;
 103     uint32_t residual;
 104 };
 105
 106 struct VirtIOBlkConf
 107 {
 108     BlockConf conf;
 109     char *serial;
 110     uint32_t scsi;
 111     uint32_t config_wce;
 112     uint32_t data_plane;
 113 };
 114
 115 struct VirtIOBlockDataPlane;
 116
 117 typedef struct VirtIOBlock {
 118     VirtIODevice parent_obj;
 119     BlockDriverState *bs;
 120     VirtQueue *vq;
 121     void *rq;
 122     QEMUBH *bh;
 123     BlockConf *conf;
 124     VirtIOBlkConf blk;
 125     unsigned short sector_mask;
 126     VMChangeStateEntry *change;
 127 #ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
 128     struct VirtIOBlockDataPlane *dataplane;
 129 #endif
 130 } VirtIOBlock;
 131
 132 #define DEFINE_VIRTIO_BLK_FEATURES(_state, _field) \
 133         DEFINE_VIRTIO_COMMON_FEATURES(_state, _field)
 134
 135 #ifdef __linux__
 136 #define DEFINE_VIRTIO_BLK_PROPERTIES(_state, _field)                          \
 137         DEFINE_BLOCK_PROPERTIES(_state, _field.conf),                         \
 138         DEFINE_BLOCK_CHS_PROPERTIES(_state, _field.conf),                     \
 139         DEFINE_PROP_STRING("serial", _state, _field.serial),                  \
 140         DEFINE_PROP_BIT("config-wce", _state, _field.config_wce, 0, true),    \
 141         DEFINE_PROP_BIT("scsi", _state, _field.scsi, 0, true)
 142 #else
 143 #define DEFINE_VIRTIO_BLK_PROPERTIES(_state, _field)                          \
 144         DEFINE_BLOCK_PROPERTIES(_state, _field.conf),                         \
 145         DEFINE_BLOCK_CHS_PROPERTIES(_state, _field.conf),                     \
 146         DEFINE_PROP_STRING("serial", _state, _field.serial),                  \
 147         DEFINE_PROP_BIT("config-wce", _state, _field.config_wce, 0, true)
 148 #endif /* __linux__ */
 149
 150 void virtio_blk_set_conf(DeviceState *dev, VirtIOBlkConf *blk);
 151
 152 #endif