xref: /freebsd/sys/geom/multipath/g_multipath.h (revision b0d29bc47dba79f6f38e67eabadfb4b32ffd9390)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2006-2007 Matthew Jacob <mjacob@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 /*
31  * Based upon work by Pawel Jakub Dawidek <pjd@FreeBSD.org> for all of the
32  * fine geom examples, and by Poul Henning Kamp <phk@FreeBSD.org> for GEOM
33  * itself, all of which is most gratefully acknowledged.
34  */
35 
36 #ifndef	_G_MULTIPATH_H_
37 #define	_G_MULTIPATH_H_
38 
39 #define	G_MULTIPATH_CLASS_NAME	"MULTIPATH"
40 #define	G_MULTIPATH_VERSION	1
41 #define	G_MULTIPATH_MAGIC	"GEOM::MULTIPATH"
42 
43 #include <sys/endian.h>
44 
45 #ifdef	_KERNEL
46 
47 struct g_multipath_softc {
48 	struct g_provider *	sc_pp;
49 	struct g_consumer *	sc_active;
50 	struct mtx		sc_mtx;
51 	char			sc_name[16];
52 	char			sc_uuid[40];
53 	off_t			sc_size;
54 	int			sc_opened;
55 	int			sc_stopping;
56 	int			sc_ndisks;
57 	int			sc_active_active; /* Active/Active mode */
58 };
59 #endif	/* _KERNEL */
60 
61 struct g_multipath_metadata {
62 	char		md_magic[16];	/* Magic Value */
63 	char 		md_uuid[40];	/* more magic */
64 	char		md_name[16];	/* a friendly name */
65 	uint32_t	md_version;	/* version */
66 	uint32_t	md_sectorsize;	/* sectorsize of provider */
67 	uint64_t	md_size;	/* absolute size of provider */
68 	uint8_t		md_active_active; /* Active/Active mode */
69 };
70 
71 static __inline void
72 multipath_metadata_encode(const struct g_multipath_metadata *, u_char *);
73 
74 static __inline void
75 multipath_metadata_decode(u_char *, struct g_multipath_metadata *);
76 
77 static __inline void
78 multipath_metadata_encode(const struct g_multipath_metadata *md, u_char *data)
79 {
80 	bcopy(md->md_magic, data, sizeof(md->md_magic));
81 	data += sizeof(md->md_magic);
82 	bcopy(md->md_uuid, data, sizeof(md->md_uuid));
83 	data += sizeof(md->md_uuid);
84 	bcopy(md->md_name, data, sizeof(md->md_name));
85 	data += sizeof(md->md_name);
86 	le32enc(data, md->md_version);
87 	data += sizeof(md->md_version);
88 	le32enc(data, md->md_sectorsize);
89 	data += sizeof(md->md_sectorsize);
90 	le64enc(data, md->md_size);
91 	data += sizeof(md->md_size);
92 	*data = md->md_active_active;
93 }
94 
95 static __inline void
96 multipath_metadata_decode(u_char *data, struct g_multipath_metadata *md)
97 {
98 	bcopy(data, md->md_magic, sizeof(md->md_magic));
99 	data += sizeof(md->md_magic);
100 	bcopy(data, md->md_uuid, sizeof(md->md_uuid));
101 	data += sizeof(md->md_uuid);
102 	bcopy(data, md->md_name, sizeof(md->md_name));
103 	data += sizeof(md->md_name);
104 	md->md_version = le32dec(data);
105 	data += sizeof(md->md_version);
106 	md->md_sectorsize = le32dec(data);
107 	data += sizeof(md->md_sectorsize);
108 	md->md_size = le64dec(data);
109 	data += sizeof(md->md_size);
110 	md->md_active_active = *data;
111 }
112 #endif	/* _G_MULTIPATH_H_ */
113