module.h revision 298493
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: stable/10/sys/sys/module.h 298493 2016-04-22 21:38:37Z emaste $
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#define	MDT_PNP_INFO	4		/* Plug and play hints record */
39
40#define	MDT_STRUCT_VERSION	1	/* version of metadata structure */
41#define	MDT_SETNAME	"modmetadata_set"
42
43typedef enum modeventtype {
44	MOD_LOAD,
45	MOD_UNLOAD,
46	MOD_SHUTDOWN,
47	MOD_QUIESCE
48} modeventtype_t;
49
50typedef struct module *module_t;
51typedef int (*modeventhand_t)(module_t, int /* modeventtype_t */, void *);
52
53/*
54 * Struct for registering modules statically via SYSINIT.
55 */
56typedef struct moduledata {
57	const char	*name;		/* module name */
58	modeventhand_t  evhand;		/* event handler */
59	void		*priv;		/* extra data */
60} moduledata_t;
61
62/*
63 * A module can use this to report module specific data to the user via
64 * kldstat(2).
65 */
66typedef union modspecific {
67	int	intval;
68	u_int	uintval;
69	long	longval;
70	u_long	ulongval;
71} modspecific_t;
72
73/*
74 * Module dependency declarartion
75 */
76struct mod_depend {
77	int	md_ver_minimum;
78	int	md_ver_preferred;
79	int	md_ver_maximum;
80};
81
82/*
83 * Module version declaration
84 */
85struct mod_version {
86	int	mv_version;
87};
88
89struct mod_metadata {
90	int		md_version;	/* structure version MDTV_* */
91	int		md_type;	/* type of entry MDT_* */
92	void		*md_data;	/* specific data */
93	const char	*md_cval;	/* common string label */
94};
95
96#ifdef	_KERNEL
97
98#include <sys/linker_set.h>
99
100#define	MODULE_METADATA(uniquifier, type, data, cval)			\
101	static struct mod_metadata _mod_metadata##uniquifier = {	\
102		MDT_STRUCT_VERSION,					\
103		type,							\
104		data,							\
105		cval							\
106	};								\
107	DATA_SET(modmetadata_set, _mod_metadata##uniquifier)
108
109#define	MODULE_DEPEND(module, mdepend, vmin, vpref, vmax)		\
110	static struct mod_depend _##module##_depend_on_##mdepend	\
111	    __section(".data") = {					\
112		vmin,							\
113		vpref,							\
114		vmax							\
115	};								\
116	MODULE_METADATA(_md_##module##_on_##mdepend, MDT_DEPEND,	\
117	    &_##module##_depend_on_##mdepend, #mdepend)
118
119/*
120 * Every kernel has a 'kernel' module with the version set to
121 * __FreeBSD_version.  We embed a MODULE_DEPEND() inside every module
122 * that depends on the 'kernel' module.  It uses the current value of
123 * __FreeBSD_version as the minimum and preferred versions.  For the
124 * maximum version it rounds the version up to the end of its branch
125 * (i.e. M99999 for M.x).  This allows a module built on M.x to work
126 * on M.y systems where y >= x, but fail on M.z systems where z < x.
127 */
128#define	MODULE_KERNEL_MAXVER	(roundup(__FreeBSD_version, 100000) - 1)
129
130#define	DECLARE_MODULE_WITH_MAXVER(name, data, sub, order, maxver)	\
131	MODULE_DEPEND(name, kernel, __FreeBSD_version,			\
132	    __FreeBSD_version, maxver);			\
133	MODULE_METADATA(_md_##name, MDT_MODULE, &data, #name);		\
134	SYSINIT(name##module, sub, order, module_register_init, &data);	\
135	struct __hack
136
137#define	DECLARE_MODULE(name, data, sub, order)				\
138	DECLARE_MODULE_WITH_MAXVER(name, data, sub, order, MODULE_KERNEL_MAXVER)
139
140/*
141 * The module declared with DECLARE_MODULE_TIED can only be loaded
142 * into the kernel with exactly the same __FreeBSD_version.
143 *
144 * Use it for modules that use kernel interfaces that are not stable
145 * even on STABLE/X branches.
146 */
147#define	DECLARE_MODULE_TIED(name, data, sub, order)				\
148	DECLARE_MODULE_WITH_MAXVER(name, data, sub, order, __FreeBSD_version)
149
150#define	MODULE_VERSION(module, version)					\
151	static struct mod_version _##module##_version			\
152	    __section(".data") = {					\
153		version							\
154	};								\
155	MODULE_METADATA(_##module##_version, MDT_VERSION,		\
156	    &_##module##_version, #module)
157
158extern struct sx modules_sx;
159
160#define	MOD_XLOCK	sx_xlock(&modules_sx)
161#define	MOD_SLOCK	sx_slock(&modules_sx)
162#define	MOD_XUNLOCK	sx_xunlock(&modules_sx)
163#define	MOD_SUNLOCK	sx_sunlock(&modules_sx)
164#define	MOD_LOCK_ASSERT	sx_assert(&modules_sx, SX_LOCKED)
165#define	MOD_XLOCK_ASSERT	sx_assert(&modules_sx, SX_XLOCKED)
166
167struct linker_file;
168
169void	module_register_init(const void *);
170int	module_register(const struct moduledata *, struct linker_file *);
171module_t	module_lookupbyname(const char *);
172module_t	module_lookupbyid(int);
173int	module_quiesce(module_t);
174void	module_reference(module_t);
175void	module_release(module_t);
176int	module_unload(module_t);
177int	module_getid(module_t);
178module_t	module_getfnext(module_t);
179const char *	module_getname(module_t);
180void	module_setspecific(module_t, modspecific_t *);
181struct linker_file *module_file(module_t);
182
183#ifdef	MOD_DEBUG
184extern int mod_debug;
185#define	MOD_DEBUG_REFS	1
186
187#define	MOD_DPF(cat, args) do {						\
188	if (mod_debug & MOD_DEBUG_##cat)				\
189		printf(args);						\
190} while (0)
191
192#else	/* !MOD_DEBUG */
193
194#define	MOD_DPF(cat, args)
195#endif
196#endif	/* _KERNEL */
197
198#define	MAXMODNAME	32
199
200struct module_stat {
201	int		version;	/* set to sizeof(struct module_stat) */
202	char		name[MAXMODNAME];
203	int		refs;
204	int		id;
205	modspecific_t	data;
206};
207
208#ifndef _KERNEL
209
210#include <sys/cdefs.h>
211
212__BEGIN_DECLS
213int	modnext(int _modid);
214int	modfnext(int _modid);
215int	modstat(int _modid, struct module_stat *_stat);
216int	modfind(const char *_name);
217__END_DECLS
218
219#endif
220
221#endif	/* !_SYS_MODULE_H_ */
222