[deliverable/linux.git] / include / linux / virtio_blk.h

#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). */
	__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;
} __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 */
Commit	Line	Data
	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	#define VIRTIO_BLK_F_GEOMETRY 4 /* Legacy geometry available */
	13	#define VIRTIO_BLK_F_RO 5 /* Disk is read-only */
	14
	15	struct virtio_blk_config
	16	{
	17	/* The capacity (in 512-byte sectors). */
	18	__u64 capacity;
	19	/* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */
	20	__u32 size_max;
	21	/* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */
	22	__u32 seg_max;
	23	/* geometry the device (if VIRTIO_BLK_F_GEOMETRY) */
	24	struct virtio_blk_geometry {
	25	__u16 cylinders;
	26	__u8 heads;
	27	__u8 sectors;
	28	} geometry;
	29	} __attribute__((packed));
	30
	31	/* These two define direction. */
	32	#define VIRTIO_BLK_T_IN 0
	33	#define VIRTIO_BLK_T_OUT 1
	34
	35	/* This bit says it's a scsi command, not an actual read or write. */
	36	#define VIRTIO_BLK_T_SCSI_CMD 2
	37
	38	/* Barrier before this op. */
	39	#define VIRTIO_BLK_T_BARRIER 0x80000000
	40
	41	/* This is the first element of the read scatter-gather list. */
	42	struct virtio_blk_outhdr
	43	{
	44	/* VIRTIO_BLK_T* */
	45	__u32 type;
	46	/* io priority. */
	47	__u32 ioprio;
	48	/* Sector (ie. 512 byte offset) */
	49	__u64 sector;
	50	};
	51
	52	/* And this is the final byte of the write scatter-gather list. */
	53	#define VIRTIO_BLK_S_OK 0
	54	#define VIRTIO_BLK_S_IOERR 1
	55	#define VIRTIO_BLK_S_UNSUPP 2
	56	#endif /* _LINUX_VIRTIO_BLK_H */