summaryrefslogtreecommitdiffstats
path: root/include/linux/kmod.h
blob: d876dce217f067d39d58542c50656578ab93a5b9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
#ifndef __LINUX_KMOD_H__
#define __LINUX_KMOD_H__

/*
 *	include/linux/kmod.h
 *
 *      This program is free software; you can redistribute it and/or modify
 *      it under the terms of the GNU General Public License as published by
 *      the Free Software Foundation; either version 2 of the License, or
 *      (at your option) any later version.
 *
 *      This program is distributed in the hope that it will be useful,
 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *      GNU General Public License for more details.
 *
 *      You should have received a copy of the GNU General Public License
 *      along with this program; if not, write to the Free Software
 *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/gfp.h>
#include <linux/stddef.h>
#include <linux/errno.h>
#include <linux/compiler.h>
#include <linux/workqueue.h>

#define KMOD_PATH_LEN 256

#ifdef CONFIG_MODULES
extern char modprobe_path[]; /* for sysctl */
/* modprobe exit status on success, -ve on error.  Return value
 * usually useless though. */
extern int __request_module(bool wait, const char *name, ...) \
	__attribute__((format(printf, 2, 3)));
#define request_module(mod...) __request_module(true, mod)
#define request_module_nowait(mod...) __request_module(false, mod)
#define try_then_request_module(x, mod...) \
	((x) ?: (__request_module(true, mod), (x)))
#else
static inline int request_module(const char *name, ...) { return -ENOSYS; }
static inline int request_module_nowait(const char *name, ...) { return -ENOSYS; }
#define try_then_request_module(x, mod...) (x)
#endif


struct key;
struct file;

enum umh_wait {
	UMH_NO_WAIT = -1,	/* don't wait at all */
	UMH_WAIT_EXEC = 0,	/* wait for the exec, but not the process */
	UMH_WAIT_PROC = 1,	/* wait for the process to complete */
};

struct subprocess_info {
	struct work_struct work;
	struct completion *complete;
	struct cred *cred;
	char *path;
	char **argv;
	char **envp;
	enum umh_wait wait;
	int retval;
	int (*init)(struct subprocess_info *info);
	void (*cleanup)(struct subprocess_info *info);
	void *data;
};

/* Allocate a subprocess_info structure */
struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
						  char **envp, gfp_t gfp_mask);

/* Set various pieces of state into the subprocess_info structure */
void call_usermodehelper_setfns(struct subprocess_info *info,
		    int (*init)(struct subprocess_info *info),
		    void (*cleanup)(struct subprocess_info *info),
		    void *data);

/* Actually execute the sub-process */
int call_usermodehelper_exec(struct subprocess_info *info, enum umh_wait wait);

/* Free the subprocess_info. This is only needed if you're not going
   to call call_usermodehelper_exec */
void call_usermodehelper_freeinfo(struct subprocess_info *info);

static inline int
call_usermodehelper_fns(char *path, char **argv, char **envp,
			enum umh_wait wait,
			int (*init)(struct subprocess_info *info),
			void (*cleanup)(struct subprocess_info *), void *data)
{
	struct subprocess_info *info;
	gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;

	info = call_usermodehelper_setup(path, argv, envp, gfp_mask);

	if (info == NULL)
		return -ENOMEM;

	call_usermodehelper_setfns(info, init, cleanup, data);

	return call_usermodehelper_exec(info, wait);
}

static inline int
call_usermodehelper(char *path, char **argv, char **envp, enum umh_wait wait)
{
	return call_usermodehelper_fns(path, argv, envp, wait,
				       NULL, NULL, NULL);
}

extern void usermodehelper_init(void);

extern int usermodehelper_disable(void);
extern void usermodehelper_enable(void);

#endif /* __LINUX_KMOD_H__ */