include/linux/umh.h

File Facts

System

Linux kernel

Corpus path

include/linux/umh.h

Extension

.h

Size

1862 bytes

Lines

69

Domain

Core OS

Bucket

Core Kernel Interface

Inferred role

Core OS: implementation source

Status

source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

• Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/gfp.h
• linux/stddef.h
• linux/errno.h
• linux/compiler.h
• linux/workqueue.h
• linux/sysctl.h

Detected Declarations

• struct cred
• struct file
• struct subprocess_info
• enum umh_disable_depth
• function usermodehelper_disable
• function usermodehelper_enable

Annotated Snippet

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

extern int
call_usermodehelper(const char *path, char **argv, char **envp, int wait);

extern struct subprocess_info *
call_usermodehelper_setup(const char *path, char **argv, char **envp,
			  gfp_t gfp_mask,
			  int (*init)(struct subprocess_info *info, struct cred *new),
			  void (*cleanup)(struct subprocess_info *), void *data);

extern int
call_usermodehelper_exec(struct subprocess_info *info, int wait);

enum umh_disable_depth {
	UMH_ENABLED = 0,
	UMH_FREEZING,
	UMH_DISABLED,
};

extern int __usermodehelper_disable(enum umh_disable_depth depth);
extern void __usermodehelper_set_disable_depth(enum umh_disable_depth depth);

static inline int usermodehelper_disable(void)
{
	return __usermodehelper_disable(UMH_DISABLED);
}

static inline void usermodehelper_enable(void)
{
	__usermodehelper_set_disable_depth(UMH_ENABLED);
}

extern int usermodehelper_read_trylock(void);
extern long usermodehelper_read_lock_wait(long timeout);
extern void usermodehelper_read_unlock(void);

#endif /* __LINUX_UMH_H__ */

Annotation

• Immediate include surface: `linux/gfp.h`, `linux/stddef.h`, `linux/errno.h`, `linux/compiler.h`, `linux/workqueue.h`, `linux/sysctl.h`.
• Detected declarations: `struct cred`, `struct file`, `struct subprocess_info`, `enum umh_disable_depth`, `function usermodehelper_disable`, `function usermodehelper_enable`.
• Atlas domain: Core OS / Core Kernel Interface.
• Implementation status: source implementation candidate.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.