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