1 #ifndef __LINUX_KMOD_H__
2 #define __LINUX_KMOD_H__
3
4 /*
5 * include/linux/kmod.h
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 */
21
22 #include <linux/gfp.h>
23 #include <linux/stddef.h>
24 #include <linux/errno.h>
25 #include <linux/compiler.h>
26 #include <linux/workqueue.h>
27 #include <linux/sysctl.h>
28
29 #define KMOD_PATH_LEN 256
30
31 #ifdef CONFIG_MODULES
32 extern char modprobe_path[]; /* for sysctl */
33 /* modprobe exit status on success, -ve on error. Return value
34 * usually useless though. */
35 extern __printf(2, 3)
36 int __request_module(bool wait, const char *name, ...);
37 #define request_module(mod...) __request_module(true, mod)
38 #define request_module_nowait(mod...) __request_module(false, mod)
39 #define try_then_request_module(x, mod...) \
40 ((x) ?: (__request_module(true, mod), (x)))
41 #else
request_module(const char * name,...)42 static inline int request_module(const char *name, ...) { return -ENOSYS; }
request_module_nowait(const char * name,...)43 static inline int request_module_nowait(const char *name, ...) { return -ENOSYS; }
44 #define try_then_request_module(x, mod...) (x)
45 #endif
46
47
48 struct cred;
49 struct file;
50
51 enum umh_wait {
52 UMH_NO_WAIT = -1, /* don't wait at all */
53 UMH_WAIT_EXEC = 0, /* wait for the exec, but not the process */
54 UMH_WAIT_PROC = 1, /* wait for the process to complete */
55 };
56
57 struct subprocess_info {
58 struct work_struct work;
59 struct completion *complete;
60 char *path;
61 char **argv;
62 char **envp;
63 enum umh_wait wait;
64 int retval;
65 int (*init)(struct subprocess_info *info, struct cred *new);
66 void (*cleanup)(struct subprocess_info *info);
67 void *data;
68 };
69
70 /* Allocate a subprocess_info structure */
71 struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
72 char **envp, gfp_t gfp_mask);
73
74 /* Set various pieces of state into the subprocess_info structure */
75 void call_usermodehelper_setfns(struct subprocess_info *info,
76 int (*init)(struct subprocess_info *info, struct cred *new),
77 void (*cleanup)(struct subprocess_info *info),
78 void *data);
79
80 /* Actually execute the sub-process */
81 int call_usermodehelper_exec(struct subprocess_info *info, enum umh_wait wait);
82
83 /* Free the subprocess_info. This is only needed if you're not going
84 to call call_usermodehelper_exec */
85 void call_usermodehelper_freeinfo(struct subprocess_info *info);
86
87 static inline int
call_usermodehelper_fns(char * path,char ** argv,char ** envp,enum umh_wait wait,int (* init)(struct subprocess_info * info,struct cred * new),void (* cleanup)(struct subprocess_info *),void * data)88 call_usermodehelper_fns(char *path, char **argv, char **envp,
89 enum umh_wait wait,
90 int (*init)(struct subprocess_info *info, struct cred *new),
91 void (*cleanup)(struct subprocess_info *), void *data)
92 {
93 struct subprocess_info *info;
94 gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
95
96 info = call_usermodehelper_setup(path, argv, envp, gfp_mask);
97
98 if (info == NULL)
99 return -ENOMEM;
100
101 call_usermodehelper_setfns(info, init, cleanup, data);
102
103 return call_usermodehelper_exec(info, wait);
104 }
105
106 static inline int
call_usermodehelper(char * path,char ** argv,char ** envp,enum umh_wait wait)107 call_usermodehelper(char *path, char **argv, char **envp, enum umh_wait wait)
108 {
109 return call_usermodehelper_fns(path, argv, envp, wait,
110 NULL, NULL, NULL);
111 }
112
113 extern struct ctl_table usermodehelper_table[];
114
115 extern void usermodehelper_init(void);
116
117 extern int usermodehelper_disable(void);
118 extern void usermodehelper_enable(void);
119 extern bool usermodehelper_is_disabled(void);
120 extern void read_lock_usermodehelper(void);
121 extern void read_unlock_usermodehelper(void);
122
123 #endif /* __LINUX_KMOD_H__ */
124