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 #include "sysemu/iothread.h"
  20
  21 #define TYPE_VIRTIO_BLK "virtio-blk-device"
  22 #define VIRTIO_BLK(obj) \
  23         OBJECT_CHECK(VirtIOBlock, (obj), TYPE_VIRTIO_BLK)
  24
  25 /* from Linux's linux/virtio_blk.h */
  26
  27 /* The ID for virtio_block */
  28 #define VIRTIO_ID_BLOCK 2
  29
  30 /* Feature bits */
  31 #define VIRTIO_BLK_F_BARRIER    0       /* Does host support barriers? */
  32 #define VIRTIO_BLK_F_SIZE_MAX   1       /* Indicates maximum segment size */
  33 #define VIRTIO_BLK_F_SEG_MAX    2       /* Indicates maximum # of segments */
  34 #define VIRTIO_BLK_F_GEOMETRY   4       /* Indicates support of legacy geometry */
  35 #define VIRTIO_BLK_F_RO         5       /* Disk is read-only */
  36 #define VIRTIO_BLK_F_BLK_SIZE   6       /* Block size of disk is available*/
  37 #define VIRTIO_BLK_F_SCSI       7       /* Supports scsi command passthru */
  38 /* #define VIRTIO_BLK_F_IDENTIFY   8       ATA IDENTIFY supported, DEPRECATED */
  39 #define VIRTIO_BLK_F_WCE        9       /* write cache enabled */
  40 #define VIRTIO_BLK_F_TOPOLOGY   10      /* Topology information is available */
  41 #define VIRTIO_BLK_F_CONFIG_WCE 11      /* write cache configurable */
  42
  43 #define VIRTIO_BLK_ID_BYTES     20      /* ID string length */
  44
  45 struct virtio_blk_config
  46 {
  47     uint64_t capacity;
  48     uint32_t size_max;
  49     uint32_t seg_max;
  50     uint16_t cylinders;
  51     uint8_t heads;
  52     uint8_t sectors;
  53     uint32_t blk_size;
  54     uint8_t physical_block_exp;
  55     uint8_t alignment_offset;
  56     uint16_t min_io_size;
  57     uint32_t opt_io_size;
  58     uint8_t wce;
  59 } QEMU_PACKED;
  60
  61 /* These two define direction. */
  62 #define VIRTIO_BLK_T_IN         0
  63 #define VIRTIO_BLK_T_OUT        1
  64
  65 /* This bit says it's a scsi command, not an actual read or write. */
  66 #define VIRTIO_BLK_T_SCSI_CMD   2
  67
  68 /* Flush the volatile write cache */
  69 #define VIRTIO_BLK_T_FLUSH      4
  70
  71 /* return the device ID string */
  72 #define VIRTIO_BLK_T_GET_ID     8
  73
  74 /* Barrier before this op. */
  75 #define VIRTIO_BLK_T_BARRIER    0x80000000
  76
  77 /* This is the first element of the read scatter-gather list. */
  78 struct virtio_blk_outhdr
  79 {
  80     /* VIRTIO_BLK_T* */
  81     uint32_t type;
  82     /* io priority. */
  83     uint32_t ioprio;
  84     /* Sector (ie. 512 byte offset) */
  85     uint64_t sector;
  86 };
  87
  88 #define VIRTIO_BLK_S_OK         0
  89 #define VIRTIO_BLK_S_IOERR      1
  90 #define VIRTIO_BLK_S_UNSUPP     2
  91
  92 /* This is the last element of the write scatter-gather list */
  93 struct virtio_blk_inhdr
  94 {
  95     unsigned char status;
  96 };
  97
  98 /* SCSI pass-through header */
  99 struct virtio_scsi_inhdr
 100 {
 101     uint32_t errors;
 102     uint32_t data_len;
 103     uint32_t sense_len;
 104     uint32_t residual;
 105 };
 106
 107 struct VirtIOBlkConf
 108 {
 109     BlockConf conf;
 110     IOThread *iothread;
 111     char *serial;
 112     uint32_t scsi;
 113     uint32_t config_wce;
 114     uint32_t data_plane;
 115 };
 116
 117 struct VirtIOBlockDataPlane;
 118
 119 typedef struct VirtIOBlock {
 120     VirtIODevice parent_obj;
 121     BlockDriverState *bs;
 122     VirtQueue *vq;
 123     void *rq;
 124     QEMUBH *bh;
 125     BlockConf *conf;
 126     VirtIOBlkConf blk;
 127     unsigned short sector_mask;
 128     bool original_wce;
 129     VMChangeStateEntry *change;
 130 #ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
 131     Notifier migration_state_notifier;
 132     struct VirtIOBlockDataPlane *dataplane;
 133 #endif
 134 } VirtIOBlock;
 135
 136 #define DEFINE_VIRTIO_BLK_FEATURES(_state, _field) \
 137         DEFINE_VIRTIO_COMMON_FEATURES(_state, _field)
 138
 139 #ifdef __linux__
 140 #define DEFINE_VIRTIO_BLK_PROPERTIES(_state, _field)                          \
 141         DEFINE_BLOCK_PROPERTIES(_state, _field.conf),                         \
 142         DEFINE_BLOCK_CHS_PROPERTIES(_state, _field.conf),                     \
 143         DEFINE_PROP_STRING("serial", _state, _field.serial),                  \
 144         DEFINE_PROP_BIT("config-wce", _state, _field.config_wce, 0, true),    \
 145         DEFINE_PROP_BIT("scsi", _state, _field.scsi, 0, true),                \
 146         DEFINE_PROP_IOTHREAD("x-iothread", _state, _field.iothread)
 147 #else
 148 #define DEFINE_VIRTIO_BLK_PROPERTIES(_state, _field)                          \
 149         DEFINE_BLOCK_PROPERTIES(_state, _field.conf),                         \
 150         DEFINE_BLOCK_CHS_PROPERTIES(_state, _field.conf),                     \
 151         DEFINE_PROP_STRING("serial", _state, _field.serial),                  \
 152         DEFINE_PROP_BIT("config-wce", _state, _field.config_wce, 0, true),    \
 153         DEFINE_PROP_IOTHREAD("x-iothread", _state, _field.iothread)
 154 #endif /* __linux__ */
 155
 156 void virtio_blk_set_conf(DeviceState *dev, VirtIOBlkConf *blk);
 157
 158 int virtio_blk_handle_scsi_req(VirtIOBlock *blk,
 159                                VirtQueueElement *elem);
 160
 161 #endif