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 
29 struct request;
30 struct device;
31 struct scatterlist;
32 struct request_queue;
33 
34 struct bsg_buffer {
35 	unsigned int payload_len;
36 	int sg_cnt;
37 	struct scatterlist *sg_list;
38 };
39 
40 struct bsg_job {
41 	struct device *dev;
42 
43 	struct kref kref;
44 
45 	unsigned int timeout;
46 
47 	/* Transport/driver specific request/reply structs */
48 	void *request;
49 	void *reply;
50 
51 	unsigned int request_len;
52 	unsigned int reply_len;
53 	/*
54 	 * On entry : reply_len indicates the buffer size allocated for
55 	 * the reply.
56 	 *
57 	 * Upon completion : the message handler must set reply_len
58 	 *  to indicates the size of the reply to be returned to the
59 	 *  caller.
60 	 */
61 
62 	/* DMA payloads for the request/response */
63 	struct bsg_buffer request_payload;
64 	struct bsg_buffer reply_payload;
65 
66 	int result;
67 	unsigned int reply_payload_rcv_len;
68 
69 	void *dd_data;		/* Used for driver-specific storage */
70 };
71 
72 void bsg_job_done(struct bsg_job *job, int result,
73 		  unsigned int reply_payload_rcv_len);
74 struct request_queue *bsg_setup_queue(struct device *dev, const char *name,
75 		bsg_job_fn *job_fn, int dd_job_size);
76 void bsg_job_put(struct bsg_job *job);
77 int __must_check bsg_job_get(struct bsg_job *job);
78 
79 #endif
80