ref: 9b874fb5cb093713f4850c922936cc1d04378303
dir: /sys/src/9/xen/xen-public/io/vscsiif.h/
/******************************************************************************
* vscsiif.h
*
* Based on the blkif.h code.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
* Copyright(c) FUJITSU Limited 2008.
*/
#ifndef __XEN__PUBLIC_IO_SCSI_H__
#define __XEN__PUBLIC_IO_SCSI_H__
#include "ring.h"
#include "../grant_table.h"
/* commands between backend and frontend */
#define VSCSIIF_ACT_SCSI_CDB 1 /* SCSI CDB command */
#define VSCSIIF_ACT_SCSI_ABORT 2 /* SCSI Device(Lun) Abort*/
#define VSCSIIF_ACT_SCSI_RESET 3 /* SCSI Device(Lun) Reset*/
#define VSCSIIF_ACT_SCSI_SG_PRESET 4 /* Preset SG elements */
/*
* Maximum scatter/gather segments per request.
*
* Considering balance between allocating at least 16 "vscsiif_request"
* structures on one page (4096 bytes) and the number of scatter/gather
* elements needed, we decided to use 26 as a magic number.
*/
#define VSCSIIF_SG_TABLESIZE 26
/*
* based on Linux kernel 2.6.18
*/
#define VSCSIIF_MAX_COMMAND_SIZE 16
#define VSCSIIF_SENSE_BUFFERSIZE 96
struct scsiif_request_segment {
grant_ref_t gref;
uint16_t offset;
uint16_t length;
};
typedef struct scsiif_request_segment vscsiif_segment_t;
struct vscsiif_request {
uint16_t rqid; /* private guest value, echoed in resp */
uint8_t act; /* command between backend and frontend */
uint8_t cmd_len;
uint8_t cmnd[VSCSIIF_MAX_COMMAND_SIZE];
uint16_t timeout_per_command; /* The command is issued by twice
the value in Backend. */
uint16_t channel, id, lun;
uint16_t padding;
uint8_t sc_data_direction; /* for DMA_TO_DEVICE(1)
DMA_FROM_DEVICE(2)
DMA_NONE(3) requests */
uint8_t nr_segments; /* Number of pieces of scatter-gather */
vscsiif_segment_t seg[VSCSIIF_SG_TABLESIZE];
uint32_t reserved[3];
};
typedef struct vscsiif_request vscsiif_request_t;
#define VSCSIIF_SG_LIST_SIZE ((sizeof(vscsiif_request_t) - 4) \
/ sizeof(vscsiif_segment_t))
struct vscsiif_sg_list {
/* First two fields must match struct vscsiif_request! */
uint16_t rqid; /* private guest value, must match main req */
uint8_t act; /* VSCSIIF_ACT_SCSI_SG_PRESET */
uint8_t nr_segments; /* Number of pieces of scatter-gather */
vscsiif_segment_t seg[VSCSIIF_SG_LIST_SIZE];
};
typedef struct vscsiif_sg_list vscsiif_sg_list_t;
struct vscsiif_response {
uint16_t rqid;
uint8_t act; /* valid only when backend supports SG_PRESET */
uint8_t sense_len;
uint8_t sense_buffer[VSCSIIF_SENSE_BUFFERSIZE];
int32_t rslt;
uint32_t residual_len; /* request bufflen -
return the value from physical device */
uint32_t reserved[36];
};
typedef struct vscsiif_response vscsiif_response_t;
DEFINE_RING_TYPES(vscsiif, struct vscsiif_request, struct vscsiif_response);
#endif /*__XEN__PUBLIC_IO_SCSI_H__*/
/*
* Local variables:
* mode: C
* c-file-style: "BSD"
* c-basic-offset: 4
* tab-width: 4
* indent-tabs-mode: nil
* End:
*/