1 #ifndef _LINUX_VIRTIO_BLK_H 2 #define _LINUX_VIRTIO_BLK_H 3 #include <linux/virtio_config.h> 4 5 /* The ID for virtio_block */ 6 #define VIRTIO_ID_BLOCK 2 7 8 /* Feature bits */ 9 #define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */ 10 #define VIRTIO_BLK_F_SIZE_MAX 1 /* Indicates maximum segment size */ 11 #define VIRTIO_BLK_F_SEG_MAX 2 /* Indicates maximum # of segments */ 12 13 struct virtio_blk_config 14 { 15 /* The capacity (in 512-byte sectors). */ 16 __le64 capacity; 17 /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */ 18 __le32 size_max; 19 /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */ 20 __le32 seg_max; 21 } __attribute__((packed)); 22 23 /* These two define direction. */ 24 #define VIRTIO_BLK_T_IN 0 25 #define VIRTIO_BLK_T_OUT 1 26 27 /* This bit says it's a scsi command, not an actual read or write. */ 28 #define VIRTIO_BLK_T_SCSI_CMD 2 29 30 /* Barrier before this op. */ 31 #define VIRTIO_BLK_T_BARRIER 0x80000000 32 33 /* This is the first element of the read scatter-gather list. */ 34 struct virtio_blk_outhdr 35 { 36 /* VIRTIO_BLK_T* */ 37 __u32 type; 38 /* io priority. */ 39 __u32 ioprio; 40 /* Sector (ie. 512 byte offset) */ 41 __u64 sector; 42 }; 43 44 #define VIRTIO_BLK_S_OK 0 45 #define VIRTIO_BLK_S_IOERR 1 46 #define VIRTIO_BLK_S_UNSUPP 2 47 48 /* This is the first element of the write scatter-gather list */ 49 struct virtio_blk_inhdr 50 { 51 unsigned char status; 52 }; 53 #endif /* _LINUX_VIRTIO_BLK_H */ 54