xref: /freebsd/sys/geom/gate/g_gate.h (revision a35d88931c87cfe6bd38f01d7bad22140b3b38f3)
1 /*-
2  * Copyright (c) 2004 Pawel Jakub Dawidek <pjd@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  * $FreeBSD$
27  */
28 
29 #ifndef _G_GATE_H_
30 #define _G_GATE_H_
31 
32 #include <sys/param.h>
33 #include <sys/lock.h>
34 #include <sys/mutex.h>
35 #include <sys/queue.h>
36 
37 #include <geom/geom.h>
38 
39 #define	G_GATE_CLASS_NAME	"GATE"
40 #define	G_GATE_PROVIDER_NAME	"ggate"
41 #define	G_GATE_MOD_NAME		"ggate"
42 #define	G_GATE_CTL_NAME		"ggctl"
43 
44 #define G_GATE_VERSION		0
45 
46 /*
47  * Maximum number of request that can be stored in
48  * the queue when there are no workers.
49  */
50 #define	G_GATE_MAX_QUEUE_SIZE	4096
51 
52 #define	G_GATE_FLAG_READONLY	0x0001
53 #define	G_GATE_FLAG_WRITEONLY	0x0002
54 #define	G_GATE_FLAG_DESTROY	0x1000
55 #define	G_GATE_USERFLAGS	(G_GATE_FLAG_READONLY | G_GATE_FLAG_WRITEONLY)
56 
57 #define G_GATE_CMD_CREATE	_IOWR('m', 0, struct g_gate_ctl_create)
58 #define G_GATE_CMD_DESTROY	_IOWR('m', 1, struct g_gate_ctl_destroy)
59 #define G_GATE_CMD_START	_IOWR('m', 2, struct g_gate_ctl_io)
60 #define G_GATE_CMD_DONE		_IOWR('m', 3, struct g_gate_ctl_io)
61 
62 #define	G_GATE_INFOSIZE		2048
63 
64 #ifdef _KERNEL
65 /*
66  * 'P:' means 'Protected by'.
67  */
68 struct g_gate_softc {
69 	int			 sc_unit;		/* P: (read-only) */
70 	int16_t			 sc_ref;		/* P: g_gate_list_mtx */
71 	struct g_provider	*sc_provider;		/* P: (read-only) */
72 	uint32_t		 sc_flags;		/* P: (read-only) */
73 
74 	struct bio_queue_head	 sc_inqueue;		/* P: sc_inqueue_mtx */
75 	struct mtx		 sc_inqueue_mtx;
76 	struct bio_queue_head	 sc_outqueue;		/* P: sc_outqueue_mtx */
77 	struct mtx		 sc_outqueue_mtx;
78 	uint32_t		 sc_queue_count;	/* P: (atomic) */
79 	uint32_t		 sc_queue_size;		/* P: (read-only) */
80 	u_int			 sc_timeout;		/* P: (read-only) */
81 	struct callout		 sc_callout;		/* P: (modified only
82 							       from callout
83 							       thread) */
84 	uintptr_t		 sc_seq;		/* P: (modified only
85 							       from g_down
86 							       thread) */
87 	LIST_ENTRY(g_gate_softc) sc_next;		/* P: g_gate_list_mtx */
88 	char			 sc_info[G_GATE_INFOSIZE]; /* P: (read-only) */
89 };
90 #define	sc_name	sc_provider->geom->name
91 
92 #define	G_GATE_DEBUG(lvl, ...)	do {					\
93 	if (g_gate_debug >= (lvl)) {					\
94 		printf("GEOM_GATE");					\
95 		if (g_gate_debug > 0)					\
96 			printf("[%u]", lvl);				\
97 		printf(": ");						\
98 		printf(__VA_ARGS__);					\
99 		printf("\n");						\
100 	}								\
101 } while (0)
102 #define	G_GATE_LOGREQ(lvl, bp, ...)	do {				\
103 	if (g_gate_debug >= (lvl)) {					\
104 		printf("GEOM_GATE");					\
105 		if (g_gate_debug > 0)					\
106 			printf("[%u]", lvl);				\
107 		printf(": ");						\
108 		printf(__VA_ARGS__);					\
109 		printf(" ");						\
110 		g_print_bio(bp);					\
111 		printf("\n");						\
112 	}								\
113 } while (0)
114 #endif	/* !_KERNEL */
115 
116 struct g_gate_ctl_create {
117 	u_int	gctl_version;
118 	off_t	gctl_mediasize;
119 	u_int	gctl_sectorsize;
120 	u_int	gctl_flags;
121 	u_int	gctl_maxcount;
122 	u_int	gctl_timeout;
123 	char	gctl_info[G_GATE_INFOSIZE];
124 	int	gctl_unit;	/* out */
125 };
126 
127 struct g_gate_ctl_destroy {
128 	u_int	gctl_version;
129 	int	gctl_unit;
130 	int	gctl_force;
131 };
132 
133 struct g_gate_ctl_io {
134 	u_int		 gctl_version;
135 	int		 gctl_unit;
136 	uintptr_t	 gctl_seq;
137 	u_int		 gctl_cmd;
138 	off_t		 gctl_offset;
139 	off_t		 gctl_length;
140 	void		*gctl_data;
141 	int		 gctl_error;
142 };
143 #endif	/* !_G_GATE_H_ */
144