g_multipath.h revision 260478 
1/*-
2 * Copyright (c) 2006-2007 Matthew Jacob <mjacob@FreeBSD.org>
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
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: stable/10/sys/geom/multipath/g_multipath.h 260478 2014-01-09 11:11:47Z mav $
27 */
28/*
29 * Based upon work by Pawel Jakub Dawidek <pjd@FreeBSD.org> for all of the
30 * fine geom examples, and by Poul Henning Kamp <phk@FreeBSD.org> for GEOM
31 * itself, all of which is most gratefully acknowledged.
32 */
33
34#ifndef	_G_MULTIPATH_H_
35#define	_G_MULTIPATH_H_
36
37#define	G_MULTIPATH_CLASS_NAME	"MULTIPATH"
38#define	G_MULTIPATH_VERSION	1
39#define	G_MULTIPATH_MAGIC	"GEOM::MULTIPATH"
40
41#include <sys/endian.h>
42
43#ifdef	_KERNEL
44
45struct g_multipath_softc {
46	struct g_provider *	sc_pp;
47	struct g_consumer *	sc_active;
48	struct mtx		sc_mtx;
49	char			sc_name[16];
50	char			sc_uuid[40];
51	off_t			sc_size;
52	int			sc_opened;
53	int			sc_stopping;
54	int			sc_ndisks;
55	int			sc_active_active; /* Active/Active mode */
56};
57#endif	/* _KERNEL */
58
59struct g_multipath_metadata {
60	char		md_magic[16];	/* Magic Value */
61	char 		md_uuid[40];	/* more magic */
62	char		md_name[16];	/* a friendly name */
63	uint32_t	md_version;	/* version */
64	uint32_t	md_sectorsize;	/* sectorsize of provider */
65	uint64_t	md_size;	/* absolute size of provider */
66	uint8_t		md_active_active; /* Active/Active mode */
67};
68
69static __inline void
70multipath_metadata_encode(const struct g_multipath_metadata *, u_char *);
71
72static __inline void
73multipath_metadata_decode(u_char *, struct g_multipath_metadata *);
74
75static __inline void
76multipath_metadata_encode(const struct g_multipath_metadata *md, u_char *data)
77{
78	bcopy(md->md_magic, data, sizeof(md->md_magic));
79	data += sizeof(md->md_magic);
80	bcopy(md->md_uuid, data, sizeof(md->md_uuid));
81	data += sizeof(md->md_uuid);
82	bcopy(md->md_name, data, sizeof(md->md_name));
83	data += sizeof(md->md_name);
84	le32enc(data, md->md_version);
85	data += sizeof(md->md_version);
86	le32enc(data, md->md_sectorsize);
87	data += sizeof(md->md_sectorsize);
88	le64enc(data, md->md_size);
89	data += sizeof(md->md_size);
90	*data = md->md_active_active;
91}
92
93static __inline void
94multipath_metadata_decode(u_char *data, struct g_multipath_metadata *md)
95{
96	bcopy(data, md->md_magic, sizeof(md->md_magic));
97	data += sizeof(md->md_magic);
98	bcopy(data, md->md_uuid, sizeof(md->md_uuid));
99	data += sizeof(md->md_uuid);
100	bcopy(data, md->md_name, sizeof(md->md_name));
101	data += sizeof(md->md_name);
102	md->md_version = le32dec(data);
103	data += sizeof(md->md_version);
104	md->md_sectorsize = le32dec(data);
105	data += sizeof(md->md_sectorsize);
106	md->md_size = le64dec(data);
107	data += sizeof(md->md_size);
108	md->md_active_active = *data;
109}
110#endif	/* _G_MULTIPATH_H_ */
111