xemu/hw/virtio-blk.h
Christoph Hellwig 8b91408b62 fix virtio_blk_inhdr comment
The inhdr is at the end of the S/G list, not the beginning.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-05-01 09:44:11 -05:00

88 lines
2.1 KiB
C

/*
* Virtio Block Device
*
* Copyright IBM, Corp. 2007
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#ifndef _QEMU_VIRTIO_BLK_H
#define _QEMU_VIRTIO_BLK_H
#include "virtio.h"
#include "block.h"
#include "pci.h"
/* from Linux's linux/virtio_blk.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 /* Indicates support of legacy geometry */
#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 */
struct virtio_blk_config
{
uint64_t capacity;
uint32_t size_max;
uint32_t seg_max;
uint16_t cylinders;
uint8_t heads;
uint8_t sectors;
} __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* */
uint32_t type;
/* io priority. */
uint32_t ioprio;
/* Sector (ie. 512 byte offset) */
uint64_t sector;
};
#define VIRTIO_BLK_S_OK 0
#define VIRTIO_BLK_S_IOERR 1
#define VIRTIO_BLK_S_UNSUPP 2
/* This is the last element of the write scatter-gather list */
struct virtio_blk_inhdr
{
unsigned char status;
};
/* SCSI pass-through header */
struct virtio_scsi_inhdr
{
uint32_t errors;
uint32_t data_len;
uint32_t sense_len;
uint32_t residual;
};
void *virtio_blk_init(PCIBus *bus, BlockDriverState *bs);
#endif