xref: /linux-6.15/include/linux/kmod.h (revision 545e4006)
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/stddef.h>
23 #include <linux/errno.h>
24 #include <linux/compiler.h>
25 
26 #define KMOD_PATH_LEN 256
27 
28 #ifdef CONFIG_MODULES
29 /* modprobe exit status on success, -ve on error.  Return value
30  * usually useless though. */
31 extern int request_module(const char * name, ...) __attribute__ ((format (printf, 1, 2)));
32 #define try_then_request_module(x, mod...) ((x) ?: (request_module(mod), (x)))
33 #else
34 static inline int request_module(const char * name, ...) { return -ENOSYS; }
35 #define try_then_request_module(x, mod...) (x)
36 #endif
37 
38 
39 struct key;
40 struct file;
41 struct subprocess_info;
42 
43 /* Allocate a subprocess_info structure */
44 struct subprocess_info *call_usermodehelper_setup(char *path,
45 						  char **argv, char **envp);
46 
47 /* Set various pieces of state into the subprocess_info structure */
48 void call_usermodehelper_setkeys(struct subprocess_info *info,
49 				 struct key *session_keyring);
50 int call_usermodehelper_stdinpipe(struct subprocess_info *sub_info,
51 				  struct file **filp);
52 void call_usermodehelper_setcleanup(struct subprocess_info *info,
53 				    void (*cleanup)(char **argv, char **envp));
54 
55 enum umh_wait {
56 	UMH_NO_WAIT = -1,	/* don't wait at all */
57 	UMH_WAIT_EXEC = 0,	/* wait for the exec, but not the process */
58 	UMH_WAIT_PROC = 1,	/* wait for the process to complete */
59 };
60 
61 /* Actually execute the sub-process */
62 int call_usermodehelper_exec(struct subprocess_info *info, enum umh_wait wait);
63 
64 /* Free the subprocess_info. This is only needed if you're not going
65    to call call_usermodehelper_exec */
66 void call_usermodehelper_freeinfo(struct subprocess_info *info);
67 
68 static inline int
69 call_usermodehelper(char *path, char **argv, char **envp, enum umh_wait wait)
70 {
71 	struct subprocess_info *info;
72 
73 	info = call_usermodehelper_setup(path, argv, envp);
74 	if (info == NULL)
75 		return -ENOMEM;
76 	return call_usermodehelper_exec(info, wait);
77 }
78 
79 static inline int
80 call_usermodehelper_keys(char *path, char **argv, char **envp,
81 			 struct key *session_keyring, enum umh_wait wait)
82 {
83 	struct subprocess_info *info;
84 
85 	info = call_usermodehelper_setup(path, argv, envp);
86 	if (info == NULL)
87 		return -ENOMEM;
88 
89 	call_usermodehelper_setkeys(info, session_keyring);
90 	return call_usermodehelper_exec(info, wait);
91 }
92 
93 extern void usermodehelper_init(void);
94 
95 struct file;
96 extern int call_usermodehelper_pipe(char *path, char *argv[], char *envp[],
97 				    struct file **filp);
98 
99 #endif /* __LINUX_KMOD_H__ */
100