1/*
2 * BSG helper library
3 *
4 * Copyright (C) 2008 James Smart, Emulex Corporation
5 * Copyright (C) 2011 Red Hat, Inc. All rights reserved.
6 * Copyright (C) 2011 Mike Christie
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 *
22 */
23#ifndef _BLK_BSG_
24#define _BLK_BSG_
25
26#include <linux/blkdev.h>
27#include <scsi/scsi_request.h>
28
29struct request;
30struct device;
31struct scatterlist;
32struct request_queue;
33
34typedef int (bsg_job_fn) (struct bsg_job *);
35typedef enum blk_eh_timer_return (bsg_timeout_fn)(struct request *);
36
37struct bsg_buffer {
38 unsigned int payload_len;
39 int sg_cnt;
40 struct scatterlist *sg_list;
41};
42
43struct bsg_job {
44 struct device *dev;
45
46 struct kref kref;
47
48 unsigned int timeout;
49
50 /* Transport/driver specific request/reply structs */
51 void *request;
52 void *reply;
53
54 unsigned int request_len;
55 unsigned int reply_len;
56 /*
57 * On entry : reply_len indicates the buffer size allocated for
58 * the reply.
59 *
60 * Upon completion : the message handler must set reply_len
61 * to indicates the size of the reply to be returned to the
62 * caller.
63 */
64
65 /* DMA payloads for the request/response */
66 struct bsg_buffer request_payload;
67 struct bsg_buffer reply_payload;
68
69 int result;
70 unsigned int reply_payload_rcv_len;
71
72 /* BIDI support */
73 struct request *bidi_rq;
74 struct bio *bidi_bio;
75
76 void *dd_data; /* Used for driver-specific storage */
77};
78
79void bsg_job_done(struct bsg_job *job, int result,
80 unsigned int reply_payload_rcv_len);
81struct request_queue *bsg_setup_queue(struct device *dev, const char *name,
82 bsg_job_fn *job_fn, bsg_timeout_fn *timeout, int dd_job_size);
83void bsg_remove_queue(struct request_queue *q);
84void bsg_job_put(struct bsg_job *job);
85int __must_check bsg_job_get(struct bsg_job *job);
86
87#endif
88