82 lines
2.4 KiB
C
82 lines
2.4 KiB
C
#ifndef _LINUX_VIRTIO_BLK_H
|
|
#define _LINUX_VIRTIO_BLK_H
|
|
/* This header is BSD licensed so anyone can use the definitions to implement
|
|
* compatible drivers/servers. */
|
|
#include <linux/types.h>
|
|
#include <linux/virtio_ids.h>
|
|
#include <linux/virtio_config.h>
|
|
|
|
/* 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 */
|
|
#define VIRTIO_BLK_F_BLK_SIZE 6 /* Block size of disk is available*/
|
|
#define VIRTIO_BLK_F_SCSI 7 /* Supports scsi command passthru */
|
|
#define VIRTIO_BLK_F_FLUSH 9 /* Cache flush command support */
|
|
|
|
struct virtio_blk_config {
|
|
/* The capacity (in 512-byte sectors). */
|
|
__u64 capacity;
|
|
/* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */
|
|
__u32 size_max;
|
|
/* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */
|
|
__u32 seg_max;
|
|
/* geometry the device (if VIRTIO_BLK_F_GEOMETRY) */
|
|
struct virtio_blk_geometry {
|
|
__u16 cylinders;
|
|
__u8 heads;
|
|
__u8 sectors;
|
|
} geometry;
|
|
/* block size of device (if VIRTIO_BLK_F_BLK_SIZE) */
|
|
__u32 blk_size;
|
|
} __attribute__((packed));
|
|
|
|
/*
|
|
* Command types
|
|
*
|
|
* Usage is a bit tricky as some bits are used as flags and some are not.
|
|
*
|
|
* Rules:
|
|
* VIRTIO_BLK_T_OUT may be combined with VIRTIO_BLK_T_SCSI_CMD or
|
|
* VIRTIO_BLK_T_BARRIER. VIRTIO_BLK_T_FLUSH is a command of its own
|
|
* and may not be combined with any of the other flags.
|
|
*/
|
|
|
|
/* 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
|
|
|
|
/* Cache flush command */
|
|
#define VIRTIO_BLK_T_FLUSH 4
|
|
|
|
/* 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;
|
|
};
|
|
|
|
struct virtio_scsi_inhdr {
|
|
__u32 errors;
|
|
__u32 data_len;
|
|
__u32 sense_len;
|
|
__u32 residual;
|
|
};
|
|
|
|
/* 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 */
|