1 /*
2  * Copyright (c) 2008, XenSource Inc.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are met:
7  *     * Redistributions of source code must retain the above copyright
8  *       notice, this list of conditions and the following disclaimer.
9  *     * Redistributions in binary form must reproduce the above copyright
10  *       notice, this list of conditions and the following disclaimer in the
11  *       documentation and/or other materials provided with the distribution.
12  *     * Neither the name of XenSource Inc. nor the names of its contributors
13  *       may be used to endorse or promote products derived from this software
14  *       without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
20  * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
21  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
23  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
24  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
25  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
26  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 #ifndef _TAPDISK_RING_H_
29 #define _TAPDISK_RING_H_
30 
31 #include <inttypes.h>
32 
33 #include <xenctrl.h>
34 #include <xen/io/ring.h>
35 
36 typedef struct td_uring             td_uring_t;
37 typedef struct td_uring_header      td_uring_header_t;
38 typedef struct td_uring_request     td_uring_request_t;
39 typedef struct td_uring_response    td_uring_response_t;
40 
41 struct td_uring {
42 	int                         ctlfd;
43 
44 	char                       *shmem_path;
45 	char                       *ctlfd_path;
46 
47 	void                       *shmem;
48 	void                       *ring_area;
49 	void                       *data_area;
50 };
51 
52 struct td_uring_header {
53 	char                        cookie[8];
54 	uint32_t                    version;
55 	uint32_t                    shmem_size;
56 	uint32_t                    ring_size;
57 	uint32_t                    data_size;
58 	char                        reserved[4064];
59 };
60 
61 struct td_uring_request {
62 	uint8_t                     op;
63 	uint64_t                    id;
64 	uint64_t                    sec;
65 	uint32_t                    secs;
66 	uint32_t                    offset;
67 };
68 
69 struct td_uring_response {
70 	uint8_t                     op;
71 	uint64_t                    id;
72 	uint8_t                     status;
73 };
74 
75 DEFINE_RING_TYPES(td_uring, td_uring_request_t, td_uring_response_t);
76 
77 int tapdisk_uring_create(td_uring_t *, const char *location,
78 			uint32_t ring_size, uint32_t data_size);
79 int tapdisk_uring_destroy(td_uring_t *);
80 
81 int tapdisk_uring_connect(td_uring_t *, const char *location);
82 int tapdisk_uring_disconnect(td_uring_t *);
83 
84 int tapdisk_uring_poll(td_uring_t *);
85 int tapdisk_uring_kick(td_uring_t *);
86 
87 #endif
88