vscsiif.h revision 251767 
1/******************************************************************************
2 * vscsiif.h
3 *
4 * Based on the blkif.h code.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to
8 * deal in the Software without restriction, including without limitation the
9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22 * DEALINGS IN THE SOFTWARE.
23 *
24 * Copyright(c) FUJITSU Limited 2008.
25 */
26
27#ifndef __XEN__PUBLIC_IO_SCSI_H__
28#define __XEN__PUBLIC_IO_SCSI_H__
29
30#include "ring.h"
31#include "../grant_table.h"
32
33/* command between backend and frontend */
34#define VSCSIIF_ACT_SCSI_CDB         1    /* SCSI CDB command */
35#define VSCSIIF_ACT_SCSI_ABORT       2    /* SCSI Device(Lun) Abort*/
36#define VSCSIIF_ACT_SCSI_RESET       3    /* SCSI Device(Lun) Reset*/
37
38
39#define VSCSIIF_BACK_MAX_PENDING_REQS    128
40
41/*
42 * Maximum scatter/gather segments per request.
43 *
44 * Considering balance between allocating al least 16 "vscsiif_request"
45 * structures on one page (4096bytes) and number of scatter gather
46 * needed, we decided to use 26 as a magic number.
47 */
48#define VSCSIIF_SG_TABLESIZE             26
49
50/*
51 * base on linux kernel 2.6.18
52 */
53#define VSCSIIF_MAX_COMMAND_SIZE         16
54#define VSCSIIF_SENSE_BUFFERSIZE         96
55
56
57struct vscsiif_request {
58    uint16_t rqid;          /* private guest value, echoed in resp  */
59    uint8_t act;            /* command between backend and frontend */
60    uint8_t cmd_len;
61
62    uint8_t cmnd[VSCSIIF_MAX_COMMAND_SIZE];
63    uint16_t timeout_per_command;     /* The command is issued by twice
64                                         the value in Backend. */
65    uint16_t channel, id, lun;
66    uint16_t padding;
67    uint8_t sc_data_direction;        /* for DMA_TO_DEVICE(1)
68                                         DMA_FROM_DEVICE(2)
69                                         DMA_NONE(3) requests  */
70    uint8_t nr_segments;              /* Number of pieces of scatter-gather */
71
72    struct scsiif_request_segment {
73        grant_ref_t gref;
74        uint16_t offset;
75        uint16_t length;
76    } seg[VSCSIIF_SG_TABLESIZE];
77    uint32_t reserved[3];
78};
79typedef struct vscsiif_request vscsiif_request_t;
80
81struct vscsiif_response {
82    uint16_t rqid;
83    uint8_t padding;
84    uint8_t sense_len;
85    uint8_t sense_buffer[VSCSIIF_SENSE_BUFFERSIZE];
86    int32_t rslt;
87    uint32_t residual_len;     /* request bufflen -
88                                  return the value from physical device */
89    uint32_t reserved[36];
90};
91typedef struct vscsiif_response vscsiif_response_t;
92
93DEFINE_RING_TYPES(vscsiif, struct vscsiif_request, struct vscsiif_response);
94
95
96#endif  /*__XEN__PUBLIC_IO_SCSI_H__*/
97/*
98 * Local variables:
99 * mode: C
100 * c-set-style: "BSD"
101 * c-basic-offset: 4
102 * tab-width: 4
103 * indent-tabs-mode: nil
104 * End:
105 */
106