1/*-
2 * Copyright (c) 1997 Doug Rabson
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 AUTHOR 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 AUTHOR 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: releng/10.3/sys/sys/module.h 283642 2015-05-28 06:45:13Z dim $
27 */
28
29#ifndef _SYS_MODULE_H_
30#define _SYS_MODULE_H_
31
32/*
33 * Module metadata types
34 */
35#define	MDT_DEPEND	1		/* argument is a module name */
36#define	MDT_MODULE	2		/* module declaration */
37#define	MDT_VERSION	3		/* module version(s) */
38
39#define	MDT_STRUCT_VERSION	1	/* version of metadata structure */
40#define	MDT_SETNAME	"modmetadata_set"
41
42typedef enum modeventtype {
43	MOD_LOAD,
44	MOD_UNLOAD,
45	MOD_SHUTDOWN,
46	MOD_QUIESCE
47} modeventtype_t;
48
49typedef struct module *module_t;
50typedef int (*modeventhand_t)(module_t, int /* modeventtype_t */, void *);
51
52/*
53 * Struct for registering modules statically via SYSINIT.
54 */
55typedef struct moduledata {
56	const char	*name;		/* module name */
57	modeventhand_t  evhand;		/* event handler */
58	void		*priv;		/* extra data */
59} moduledata_t;
60
61/*
62 * A module can use this to report module specific data to the user via
63 * kldstat(2).
64 */
65typedef union modspecific {
66	int	intval;
67	u_int	uintval;
68	long	longval;
69	u_long	ulongval;
70} modspecific_t;
71
72/*
73 * Module dependency declarartion
74 */
75struct mod_depend {
76	int	md_ver_minimum;
77	int	md_ver_preferred;
78	int	md_ver_maximum;
79};
80
81/*
82 * Module version declaration
83 */
84struct mod_version {
85	int	mv_version;
86};
87
88struct mod_metadata {
89	int		md_version;	/* structure version MDTV_* */
90	int		md_type;	/* type of entry MDT_* */
91	void		*md_data;	/* specific data */
92	const char	*md_cval;	/* common string label */
93};
94
95#ifdef	_KERNEL
96
97#include <sys/linker_set.h>
98
99#define	MODULE_METADATA(uniquifier, type, data, cval)			\
100	static struct mod_metadata _mod_metadata##uniquifier = {	\
101		MDT_STRUCT_VERSION,					\
102		type,							\
103		data,							\
104		cval							\
105	};								\
106	DATA_SET(modmetadata_set, _mod_metadata##uniquifier)
107
108#define	MODULE_DEPEND(module, mdepend, vmin, vpref, vmax)		\
109	static struct mod_depend _##module##_depend_on_##mdepend	\
110	    __section(".data") = {					\
111		vmin,							\
112		vpref,							\
113		vmax							\
114	};								\
115	MODULE_METADATA(_md_##module##_on_##mdepend, MDT_DEPEND,	\
116	    &_##module##_depend_on_##mdepend, #mdepend)
117
118/*
119 * Every kernel has a 'kernel' module with the version set to
120 * __FreeBSD_version.  We embed a MODULE_DEPEND() inside every module
121 * that depends on the 'kernel' module.  It uses the current value of
122 * __FreeBSD_version as the minimum and preferred versions.  For the
123 * maximum version it rounds the version up to the end of its branch
124 * (i.e. M99999 for M.x).  This allows a module built on M.x to work
125 * on M.y systems where y >= x, but fail on M.z systems where z < x.
126 */
127#define	MODULE_KERNEL_MAXVER	(roundup(__FreeBSD_version, 100000) - 1)
128
129#define	DECLARE_MODULE_WITH_MAXVER(name, data, sub, order, maxver)	\
130	MODULE_DEPEND(name, kernel, __FreeBSD_version,			\
131	    __FreeBSD_version, maxver);			\
132	MODULE_METADATA(_md_##name, MDT_MODULE, &data, #name);		\
133	SYSINIT(name##module, sub, order, module_register_init, &data);	\
134	struct __hack
135
136#define	DECLARE_MODULE(name, data, sub, order)				\
137	DECLARE_MODULE_WITH_MAXVER(name, data, sub, order, MODULE_KERNEL_MAXVER)
138
139/*
140 * The module declared with DECLARE_MODULE_TIED can only be loaded
141 * into the kernel with exactly the same __FreeBSD_version.
142 *
143 * Use it for modules that use kernel interfaces that are not stable
144 * even on STABLE/X branches.
145 */
146#define	DECLARE_MODULE_TIED(name, data, sub, order)				\
147	DECLARE_MODULE_WITH_MAXVER(name, data, sub, order, __FreeBSD_version)
148
149#define	MODULE_VERSION(module, version)					\
150	static struct mod_version _##module##_version			\
151	    __section(".data") = {					\
152		version							\
153	};								\
154	MODULE_METADATA(_##module##_version, MDT_VERSION,		\
155	    &_##module##_version, #module)
156
157extern struct sx modules_sx;
158
159#define	MOD_XLOCK	sx_xlock(&modules_sx)
160#define	MOD_SLOCK	sx_slock(&modules_sx)
161#define	MOD_XUNLOCK	sx_xunlock(&modules_sx)
162#define	MOD_SUNLOCK	sx_sunlock(&modules_sx)
163#define	MOD_LOCK_ASSERT	sx_assert(&modules_sx, SX_LOCKED)
164#define	MOD_XLOCK_ASSERT	sx_assert(&modules_sx, SX_XLOCKED)
165
166struct linker_file;
167
168void	module_register_init(const void *);
169int	module_register(const struct moduledata *, struct linker_file *);
170module_t	module_lookupbyname(const char *);
171module_t	module_lookupbyid(int);
172int	module_quiesce(module_t);
173void	module_reference(module_t);
174void	module_release(module_t);
175int	module_unload(module_t);
176int	module_getid(module_t);
177module_t	module_getfnext(module_t);
178const char *	module_getname(module_t);
179void	module_setspecific(module_t, modspecific_t *);
180struct linker_file *module_file(module_t);
181
182#ifdef	MOD_DEBUG
183extern int mod_debug;
184#define	MOD_DEBUG_REFS	1
185
186#define	MOD_DPF(cat, args) do {						\
187	if (mod_debug & MOD_DEBUG_##cat)				\
188		printf(args);						\
189} while (0)
190
191#else	/* !MOD_DEBUG */
192
193#define	MOD_DPF(cat, args)
194#endif
195#endif	/* _KERNEL */
196
197#define	MAXMODNAME	32
198
199struct module_stat {
200	int		version;	/* set to sizeof(struct module_stat) */
201	char		name[MAXMODNAME];
202	int		refs;
203	int		id;
204	modspecific_t	data;
205};
206
207#ifndef _KERNEL
208
209#include <sys/cdefs.h>
210
211__BEGIN_DECLS
212int	modnext(int _modid);
213int	modfnext(int _modid);
214int	modstat(int _modid, struct module_stat *_stat);
215int	modfind(const char *_name);
216__END_DECLS
217
218#endif
219
220#endif	/* !_SYS_MODULE_H_ */
221