xref: /netbsd/sys/sys/module.h (revision b81cd7ea)
1 /*	$NetBSD: module.h,v 1.48 2021/10/24 06:52:26 skrll Exp $	*/
2 
3 /*-
4  * Copyright (c) 2008 The NetBSD Foundation, Inc.
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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #ifndef _SYS_MODULE_H_
30 #define _SYS_MODULE_H_
31 
32 #include <sys/types.h>
33 #include <sys/param.h>
34 #include <sys/cdefs.h>
35 #include <sys/uio.h>
36 
37 #define	MAXMODNAME	32
38 #define	MAXMODDEPS	10
39 
40 /* Module classes, provided only for system boot and module validation. */
41 typedef enum modclass {
42 	MODULE_CLASS_ANY,
43 	MODULE_CLASS_MISC,
44 	MODULE_CLASS_VFS,
45 	MODULE_CLASS_DRIVER,
46 	MODULE_CLASS_EXEC,
47 	MODULE_CLASS_SECMODEL,
48 	MODULE_CLASS_BUFQ,
49 	MODULE_CLASS_MAX
50 } modclass_t;
51 
52 /* Module sources: where did it come from? */
53 typedef enum modsrc {
54 	MODULE_SOURCE_KERNEL,
55 	MODULE_SOURCE_BOOT,
56 	MODULE_SOURCE_FILESYS
57 } modsrc_t;
58 
59 /* Commands passed to module control routine. */
60 typedef enum modcmd {
61 	MODULE_CMD_INIT,		/* mandatory */
62 	MODULE_CMD_FINI,		/* mandatory */
63 	MODULE_CMD_STAT,		/* optional */
64 	MODULE_CMD_AUTOUNLOAD,		/* optional */
65 } modcmd_t;
66 
67 #ifdef _KERNEL
68 
69 #include <sys/kernel.h>
70 #include <sys/mutex.h>
71 #include <sys/queue.h>
72 #include <sys/specificdata.h>
73 
74 #include <prop/proplib.h>
75 
76 /* Module header structure. */
77 typedef struct modinfo {
78 	u_int			mi_version;
79 	modclass_t		mi_class;
80 	int			(*mi_modcmd)(modcmd_t, void *);
81 	const char		*mi_name;
82 	const char		*mi_required;
83 } const modinfo_t;
84 
85 /* Per module information, maintained by kern_module.c */
86 
87 struct sysctllog;
88 
89 typedef struct module {
90 	u_int			mod_refcnt;
91 	int			mod_flags;
92 #define MODFLG_MUST_FORCE	0x01
93 #define MODFLG_AUTO_LOADED	0x02
94 	const modinfo_t		*mod_info;
95 	struct kobj		*mod_kobj;
96 	TAILQ_ENTRY(module)	mod_chain;
97 	struct module		*(*mod_required)[MAXMODDEPS];
98 	u_int			mod_nrequired;
99 	u_int			mod_arequired;
100 	modsrc_t		mod_source;
101 	time_t			mod_autotime;
102 	specificdata_reference	mod_sdref;
103 	struct sysctllog	*mod_sysctllog;
104 } module_t;
105 
106 /*
107  * Per-module linkage.  Loadable modules have a `link_set_modules' section
108  * containing only one entry, pointing to the module's modinfo_t record.
109  * For the kernel, `link_set_modules' can contain multiple entries and
110  * records all modules built into the kernel at link time.
111  *
112  * Alternatively, in some environments rump kernels use
113  * __attribute__((constructor)) due to link sets being
114  * difficult (impossible?) to implement (e.g. GNU gold, OS X, etc.)
115  * If we're cold (read: rump_init() has not been called), we lob the
116  * module onto the list to be handled when rump_init() runs.
117  * nb. it's not possible to use in-kernel locking mechanisms here since
118  * the code runs before rump_init().  We solve the problem by decreeing
119  * that thou shalt not call dlopen()/dlclose() for rump kernel components
120  * from multiple threads before calling rump_init().
121  */
122 
123 #ifdef RUMP_USE_CTOR
124 struct modinfo_chain {
125 	const struct modinfo	*mc_info;
126 	LIST_ENTRY(modinfo_chain) mc_entries;
127 };
128 LIST_HEAD(modinfo_boot_chain, modinfo_chain);
129 #define _MODULE_REGISTER(name)						\
130 static struct modinfo_chain __CONCAT(mc,name) = {			\
131 	.mc_info = &__CONCAT(name,_modinfo),				\
132 };									\
133 static void __CONCAT(modctor_,name)(void) __attribute__((__constructor__));\
134 static void __CONCAT(modctor_,name)(void)				\
135 {									\
136 	extern struct modinfo_boot_chain modinfo_boot_chain;		\
137 	if (cold) {							\
138 		struct modinfo_chain *mc = &__CONCAT(mc,name);		\
139 		LIST_INSERT_HEAD(&modinfo_boot_chain, mc, mc_entries);	\
140 	}								\
141 }									\
142 									\
143 static void __CONCAT(moddtor_,name)(void) __attribute__((__destructor__));\
144 static void __CONCAT(moddtor_,name)(void)				\
145 {									\
146 	struct modinfo_chain *mc = &__CONCAT(mc,name);			\
147 	if (cold) {							\
148 		LIST_REMOVE(mc, mc_entries);				\
149 	}								\
150 }
151 
152 #else /* RUMP_USE_CTOR */
153 
154 #define _MODULE_REGISTER(name) __link_set_add_rodata(modules, __CONCAT(name,_modinfo));
155 
156 #endif /* RUMP_USE_CTOR */
157 
158 #define	MODULE(class, name, required)				\
159 static int __CONCAT(name,_modcmd)(modcmd_t, void *);		\
160 static const modinfo_t __CONCAT(name,_modinfo) = {		\
161 	.mi_version = __NetBSD_Version__,			\
162 	.mi_class = (class),					\
163 	.mi_modcmd = __CONCAT(name,_modcmd),			\
164 	.mi_name = __STRING(name),				\
165 	.mi_required = (required)				\
166 }; 								\
167 _MODULE_REGISTER(name)
168 
169 TAILQ_HEAD(modlist, module);
170 
171 extern struct vm_map	*module_map;
172 extern u_int		module_count;
173 extern u_int		module_builtinlist;
174 extern struct modlist	module_list;
175 extern struct modlist	module_builtins;
176 extern u_int		module_gen;
177 
178 void	module_init(void);
179 void	module_start_unload_thread(void);
180 void	module_builtin_require_force(void);
181 void	module_init_md(void);
182 void	module_init_class(modclass_t);
183 int	module_prime(const char *, void *, size_t);
184 
185 module_t *module_kernel(void);
186 const char *module_name(struct module *);
187 modsrc_t module_source(struct module *);
188 bool	module_compatible(int, int);
189 int	module_load(const char *, int, prop_dictionary_t, modclass_t);
190 int	module_builtin_add(modinfo_t * const *, size_t, bool);
191 int	module_builtin_remove(modinfo_t *, bool);
192 int	module_autoload(const char *, modclass_t);
193 int	module_unload(const char *);
194 void	module_hold(module_t *);
195 void	module_rele(module_t *);
196 int	module_find_section(const char *, void **, size_t *);
197 void	module_thread_kick(void);
198 void	module_load_vfs_init(void);
199 
200 specificdata_key_t module_specific_key_create(specificdata_key_t *, specificdata_dtor_t);
201 void	module_specific_key_delete(specificdata_key_t);
202 void	*module_getspecific(module_t *, specificdata_key_t);
203 void	module_setspecific(module_t *, specificdata_key_t, void *);
204 void	*module_register_callbacks(void (*)(struct module *),
205 				  void (*)(struct module *));
206 void	module_unregister_callbacks(void *);
207 
208 void	module_whatis(uintptr_t, void (*)(const char *, ...)
209     __printflike(1, 2));
210 void	module_print_list(void (*)(const char *, ...) __printflike(1, 2));
211 
212 #ifdef _MODULE_INTERNAL
213 extern
214 int	(*module_load_vfs_vec)(const char *, int, bool, module_t *,
215 			       prop_dictionary_t *);
216 int	module_load_vfs(const char *, int, bool, module_t *,
217 			prop_dictionary_t *);
218 void	module_error(const char *, ...) __printflike(1, 2);
219 void	module_print(const char *, ...) __printflike(1, 2);
220 #endif /* _MODULE_INTERNAL */
221 
222 #define MODULE_BASE_SIZE 64
223 extern char	module_base[MODULE_BASE_SIZE];
224 extern const char	*module_machine;
225 
226 struct netbsd32_modctl_args;
227 extern int compat32_80_modctl_compat_stub(struct lwp *,
228     const struct netbsd32_modctl_args *, register_t *);
229 
230 #else	/* _KERNEL */
231 
232 #include <stdint.h>
233 
234 #endif	/* _KERNEL */
235 
236 typedef struct modctl_load {
237 	const char *ml_filename;
238 
239 #define MODCTL_NO_PROP		0x2
240 #define MODCTL_LOAD_FORCE	0x1
241 	int ml_flags;
242 
243 	const char *ml_props;
244 	size_t ml_propslen;
245 } modctl_load_t;
246 
247 enum modctl {
248 	MODCTL_LOAD,		/* modctl_load_t *ml */
249 	MODCTL_UNLOAD,		/* char *name */
250 	MODCTL_OSTAT,		/* struct iovec *buffer */
251 	MODCTL_EXISTS,		/* enum: 0: load, 1: autoload */
252 	MODCTL_STAT		/* struct iovec *buffer */
253 };
254 
255 /*
256  * This structure is used with the newer version of MODCTL_STAT, which
257  * exports strings of arbitrary length for the list of required modules.
258  */
259 typedef struct modstat {
260 	char		ms_name[MAXMODNAME];
261 	uint64_t	ms_addr;
262 	modsrc_t	ms_source;
263 	modclass_t	ms_class;
264 	u_int		ms_size;
265 	u_int		ms_refcnt;
266 	u_int		ms_flags;
267 	u_int		ms_reqoffset;	/* offset to module's required list
268 					   from beginning of iovec buffer! */
269 } modstat_t;
270 
271 int	modctl(int, void *);
272 
273 #ifdef _KERNEL
274 /* attention: pointers passed are userland pointers!,
275    see modctl_load_t */
276 int	handle_modctl_load(const char *, int, const char *, size_t);
277 #endif
278 
279 #endif	/* !_SYS_MODULE_H_ */
280