1 /*	$NetBSD: module.h,v 1.40 2016/01/18 16:46:08 pooka 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/queue.h>
36 #include <sys/uio.h>
37 
38 #define	MAXMODNAME	32
39 #define	MAXMODDEPS	10
40 
41 /* Module classes, provided only for system boot and cosmetic purposes. */
42 typedef enum modclass {
43 	MODULE_CLASS_ANY,
44 	MODULE_CLASS_MISC,
45 	MODULE_CLASS_VFS,
46 	MODULE_CLASS_DRIVER,
47 	MODULE_CLASS_EXEC,
48 	MODULE_CLASS_SECMODEL
49 } modclass_t;
50 
51 /* Module sources: where did it come from? */
52 typedef enum modsrc {
53 	MODULE_SOURCE_KERNEL,
54 	MODULE_SOURCE_BOOT,
55 	MODULE_SOURCE_FILESYS
56 } modsrc_t;
57 
58 /* Commands passed to module control routine. */
59 typedef enum modcmd {
60 	MODULE_CMD_INIT,		/* mandatory */
61 	MODULE_CMD_FINI,		/* mandatory */
62 	MODULE_CMD_STAT,		/* optional */
63 	MODULE_CMD_AUTOUNLOAD,		/* optional */
64 } modcmd_t;
65 
66 #ifdef _KERNEL
67 
68 #include <sys/kernel.h>
69 #include <sys/mutex.h>
70 
71 #include <prop/proplib.h>
72 
73 /* Module header structure. */
74 typedef struct modinfo {
75 	u_int		mi_version;
76 	modclass_t	mi_class;
77 	int		(*mi_modcmd)(modcmd_t, void *);
78 	const char	*mi_name;
79 	const char	*mi_required;
80 } const modinfo_t;
81 
82 /* Per module information, maintained by kern_module.c */
83 typedef struct module {
84 	u_int			mod_refcnt;
85 	const modinfo_t		*mod_info;
86 	struct kobj		*mod_kobj;
87 	TAILQ_ENTRY(module)	mod_chain;
88 	struct module		*mod_required[MAXMODDEPS];
89 	u_int			mod_nrequired;
90 	modsrc_t		mod_source;
91 	time_t			mod_autotime;
92 	void 			*mod_ctf;
93 	u_int			mod_fbtentries;	/* DTrace FBT entry count */
94 	int			mod_flags;
95 #define MODFLG_MUST_FORCE	0x01
96 #define MODFLG_AUTO_LOADED	0x02
97 
98 } module_t;
99 
100 /*
101  * Per-module linkage.  Loadable modules have a `link_set_modules' section
102  * containing only one entry, pointing to the module's modinfo_t record.
103  * For the kernel, `link_set_modules' can contain multiple entries and
104  * records all modules built into the kernel at link time.
105  *
106  * Alternatively, in some environments rump kernels use
107  * __attribute__((constructor)) due to link sets being
108  * difficult (impossible?) to implement (e.g. GNU gold, OS X, etc.)
109  * If we're cold (read: rump_init() has not been called), we lob the
110  * module onto the list to be handled when rump_init() runs.
111  * nb. it's not possible to use in-kernel locking mechanisms here since
112  * the code runs before rump_init().  We solve the problem by decreeing
113  * that thou shalt not call dlopen()/dlclose() for rump kernel components
114  * from multiple threads before calling rump_init().
115  */
116 
117 #ifdef RUMP_USE_CTOR
118 struct modinfo_chain {
119 	const struct modinfo	*mc_info;
120 	LIST_ENTRY(modinfo_chain) mc_entries;
121 };
122 LIST_HEAD(modinfo_boot_chain, modinfo_chain);
123 #define _MODULE_REGISTER(name)						\
124 static struct modinfo_chain __CONCAT(mc,name) = {			\
125 	.mc_info = &__CONCAT(name,_modinfo),				\
126 };									\
127 static void __CONCAT(modctor_,name)(void) __attribute__((__constructor__));\
128 static void __CONCAT(modctor_,name)(void)				\
129 {									\
130 	extern struct modinfo_boot_chain modinfo_boot_chain;		\
131 	if (cold) {							\
132 		struct modinfo_chain *mc = &__CONCAT(mc,name);		\
133 		LIST_INSERT_HEAD(&modinfo_boot_chain, mc, mc_entries);	\
134 	}								\
135 }									\
136 									\
137 static void __CONCAT(moddtor_,name)(void) __attribute__((__destructor__));\
138 static void __CONCAT(moddtor_,name)(void)				\
139 {									\
140 	struct modinfo_chain *mc = &__CONCAT(mc,name);			\
141 	if (cold) {							\
142 		LIST_REMOVE(mc, mc_entries);				\
143 	}								\
144 }
145 
146 #else /* RUMP_USE_CTOR */
147 
148 #define _MODULE_REGISTER(name) __link_set_add_rodata(modules, __CONCAT(name,_modinfo));
149 
150 #endif /* RUMP_USE_CTOR */
151 
152 #define	MODULE(class, name, required)				\
153 static int __CONCAT(name,_modcmd)(modcmd_t, void *);		\
154 static const modinfo_t __CONCAT(name,_modinfo) = {		\
155 	.mi_version = __NetBSD_Version__,			\
156 	.mi_class = (class),					\
157 	.mi_modcmd = __CONCAT(name,_modcmd),			\
158 	.mi_name = __STRING(name),				\
159 	.mi_required = (required)				\
160 }; 								\
161 _MODULE_REGISTER(name)
162 
163 TAILQ_HEAD(modlist, module);
164 
165 extern struct vm_map	*module_map;
166 extern u_int		module_count;
167 extern u_int		module_builtinlist;
168 extern struct modlist	module_list;
169 extern struct modlist	module_builtins;
170 extern u_int		module_gen;
171 
172 void	module_init(void);
173 void	module_start_unload_thread(void);
174 void	module_builtin_require_force(void);
175 void	module_init_md(void);
176 void	module_init_class(modclass_t);
177 int	module_prime(const char *, void *, size_t);
178 
179 bool	module_compatible(int, int);
180 int	module_load(const char *, int, prop_dictionary_t, modclass_t);
181 int	module_builtin_add(modinfo_t * const *, size_t, bool);
182 int	module_builtin_remove(modinfo_t *, bool);
183 int	module_autoload(const char *, modclass_t);
184 int	module_unload(const char *);
185 int	module_hold(const char *);
186 void	module_rele(const char *);
187 int	module_find_section(const char *, void **, size_t *);
188 void	module_thread_kick(void);
189 void	module_load_vfs_init(void);
190 
191 void	module_whatis(uintptr_t, void (*)(const char *, ...)
192     __printflike(1, 2));
193 void	module_print_list(void (*)(const char *, ...) __printflike(1, 2));
194 
195 #ifdef _MODULE_INTERNAL
196 extern
197 int	(*module_load_vfs_vec)(const char *, int, bool, module_t *,
198 			       prop_dictionary_t *);
199 int	module_load_vfs(const char *, int, bool, module_t *,
200 			prop_dictionary_t *);
201 void	module_error(const char *, ...) __printflike(1, 2);
202 void	module_print(const char *, ...) __printflike(1, 2);
203 #endif /* _MODULE_INTERNAL */
204 
205 #define MODULE_BASE_SIZE 64
206 extern char	module_base[MODULE_BASE_SIZE];
207 extern const char	*module_machine;
208 
209 #else	/* _KERNEL */
210 
211 #include <stdint.h>
212 
213 #endif	/* _KERNEL */
214 
215 typedef struct modctl_load {
216 	const char *ml_filename;
217 
218 #define MODCTL_NO_PROP		0x2
219 #define MODCTL_LOAD_FORCE	0x1
220 	int ml_flags;
221 
222 	const char *ml_props;
223 	size_t ml_propslen;
224 } modctl_load_t;
225 
226 typedef enum modctl {
227 	MODCTL_LOAD,		/* modctl_load_t *ml */
228 	MODCTL_UNLOAD,		/* char *name */
229 	MODCTL_STAT,		/* struct iovec *buffer */
230 	MODCTL_EXISTS		/* enum: 0: load, 1: autoload */
231 } modctl_t;
232 
233 /*
234  * This structure intentionally has the same layout for 32 and 64
235  * bit builds.
236  */
237 typedef struct modstat {
238 	char		ms_name[MAXMODNAME];
239 	char		ms_required[MAXMODNAME * MAXMODDEPS];
240 	uint64_t	ms_addr;
241 	modsrc_t	ms_source;
242 	modclass_t	ms_class;
243 	u_int		ms_size;
244 	u_int		ms_refcnt;
245 	u_int		ms_flags;
246 	u_int		ms_reserved[3];
247 } modstat_t;
248 
249 int	modctl(int, void *);
250 
251 #ifdef _KERNEL
252 /* attention: pointers passed are userland pointers!,
253    see modctl_load_t */
254 int	handle_modctl_load(const char *, int, const char *, size_t);
255 #endif
256 
257 #endif	/* !_SYS_MODULE_H_ */
258