xref: /openbmc/linux/include/linux/umh.h (revision 861dc0b4)
1 #ifndef __LINUX_UMH_H__
2 #define __LINUX_UMH_H__
3 
4 #include <linux/gfp.h>
5 #include <linux/stddef.h>
6 #include <linux/errno.h>
7 #include <linux/compiler.h>
8 #include <linux/workqueue.h>
9 #include <linux/sysctl.h>
10 
11 struct cred;
12 struct file;
13 
14 #define UMH_NO_WAIT	0x00	/* don't wait at all */
15 #define UMH_WAIT_EXEC	0x01	/* wait for the exec, but not the process */
16 #define UMH_WAIT_PROC	0x02	/* wait for the process to complete */
17 #define UMH_KILLABLE	0x04	/* wait for EXEC/PROC killable */
18 #define UMH_FREEZABLE	0x08	/* wait for EXEC/PROC freezable */
19 
20 struct subprocess_info {
21 	struct work_struct work;
22 	struct completion *complete;
23 	const char *path;
24 	char **argv;
25 	char **envp;
26 	int wait;
27 	int retval;
28 	int (*init)(struct subprocess_info *info, struct cred *new);
29 	void (*cleanup)(struct subprocess_info *info);
30 	void *data;
31 } __randomize_layout;
32 
33 extern int
34 call_usermodehelper(const char *path, char **argv, char **envp, int wait);
35 
36 extern struct subprocess_info *
37 call_usermodehelper_setup(const char *path, char **argv, char **envp,
38 			  gfp_t gfp_mask,
39 			  int (*init)(struct subprocess_info *info, struct cred *new),
40 			  void (*cleanup)(struct subprocess_info *), void *data);
41 
42 extern int
43 call_usermodehelper_exec(struct subprocess_info *info, int wait);
44 
45 enum umh_disable_depth {
46 	UMH_ENABLED = 0,
47 	UMH_FREEZING,
48 	UMH_DISABLED,
49 };
50 
51 extern int __usermodehelper_disable(enum umh_disable_depth depth);
52 extern void __usermodehelper_set_disable_depth(enum umh_disable_depth depth);
53 
usermodehelper_disable(void)54 static inline int usermodehelper_disable(void)
55 {
56 	return __usermodehelper_disable(UMH_DISABLED);
57 }
58 
usermodehelper_enable(void)59 static inline void usermodehelper_enable(void)
60 {
61 	__usermodehelper_set_disable_depth(UMH_ENABLED);
62 }
63 
64 extern int usermodehelper_read_trylock(void);
65 extern long usermodehelper_read_lock_wait(long timeout);
66 extern void usermodehelper_read_unlock(void);
67 
68 #endif /* __LINUX_UMH_H__ */
69