| #ifndef _LINUX_VIRTIO_BLK_H |
| #define _LINUX_VIRTIO_BLK_H |
| #include <linux/virtio_config.h> |
| |
| /* The ID for virtio_block */ |
| #define VIRTIO_ID_BLOCK 2 |
| |
| /* Feature bits */ |
| #define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */ |
| #define VIRTIO_BLK_F_SIZE_MAX 1 /* Indicates maximum segment size */ |
| #define VIRTIO_BLK_F_SEG_MAX 2 /* Indicates maximum # of segments */ |
| #define VIRTIO_BLK_F_GEOMETRY 4 /* Legacy geometry available */ |
| #define VIRTIO_BLK_F_RO 5 /* Disk is read-only */ |
| |
| struct virtio_blk_config |
| { |
| /* The capacity (in 512-byte sectors). */ |
| __le64 capacity; |
| /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */ |
| __le32 size_max; |
| /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */ |
| __le32 seg_max; |
| /* geometry the device (if VIRTIO_BLK_F_GEOMETRY) */ |
| struct virtio_blk_geometry { |
| __le16 cylinders; |
| __u8 heads; |
| __u8 sectors; |
| } geometry; |
| } __attribute__((packed)); |
| |
| /* These two define direction. */ |
| #define VIRTIO_BLK_T_IN 0 |
| #define VIRTIO_BLK_T_OUT 1 |
| |
| /* This bit says it's a scsi command, not an actual read or write. */ |
| #define VIRTIO_BLK_T_SCSI_CMD 2 |
| |
| /* Barrier before this op. */ |
| #define VIRTIO_BLK_T_BARRIER 0x80000000 |
| |
| /* This is the first element of the read scatter-gather list. */ |
| struct virtio_blk_outhdr |
| { |
| /* VIRTIO_BLK_T* */ |
| __u32 type; |
| /* io priority. */ |
| __u32 ioprio; |
| /* Sector (ie. 512 byte offset) */ |
| __u64 sector; |
| }; |
| |
| /* And this is the final byte of the write scatter-gather list. */ |
| #define VIRTIO_BLK_S_OK 0 |
| #define VIRTIO_BLK_S_IOERR 1 |
| #define VIRTIO_BLK_S_UNSUPP 2 |
| #endif /* _LINUX_VIRTIO_BLK_H */ |