fs/kernfs/kernfs-internal.h

File Facts

System

Linux kernel

Corpus path

fs/kernfs/kernfs-internal.h

Extension

.h

Size

6509 bytes

Lines

237

Domain

Core OS

Bucket

VFS And Filesystem Core

Inferred role

Core OS: operation-table or driver-model contract

Status

pattern 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 an operation table; this is where Linux turns generic core objects into subsystem-specific behavior.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/lockdep.h
• linux/fs.h
• linux/mutex.h
• linux/rwsem.h
• linux/xattr.h
• linux/kernfs.h
• linux/fs_context.h

Detected Declarations

• struct kernfs_iattrs
• struct kernfs_root
• struct kernfs_super_info
• function kernfs_root_is_locked
• function kernfs_rename_is_locked
• function kernfs_set_rev
• function kernfs_inc_rev
• function kernfs_dir_changed

Annotated Snippet

extern const struct file_operations kernfs_dir_fops;
extern const struct inode_operations kernfs_dir_iops;

struct kernfs_node *kernfs_get_active(struct kernfs_node *kn);
void kernfs_put_active(struct kernfs_node *kn);
int kernfs_add_one(struct kernfs_node *kn);
struct kernfs_node *kernfs_new_node(struct kernfs_node *parent,
				    const char *name, umode_t mode,
				    kuid_t uid, kgid_t gid,
				    unsigned flags);

/*
 * file.c
 */
extern const struct file_operations kernfs_file_fops;

bool kernfs_should_drain_open_files(struct kernfs_node *kn);
void kernfs_drain_open_files(struct kernfs_node *kn);

/*
 * symlink.c
 */
extern const struct inode_operations kernfs_symlink_iops;

/*
 * kernfs locks
 */
extern struct kernfs_global_locks *kernfs_locks;

/* Hashed mutex helpers - protect per-node data structures */
static inline struct mutex *kernfs_node_lock_ptr(struct kernfs_node *kn)
{
	int idx = hash_ptr(kn, NR_KERNFS_LOCK_BITS);

	return &kernfs_locks->node_mutex[idx];
}

static inline struct mutex *kernfs_node_lock(struct kernfs_node *kn)
{
	struct mutex *lock = kernfs_node_lock_ptr(kn);

	mutex_lock(lock);
	return lock;
}

DEFINE_CLASS(kernfs_node_lock, struct mutex *,
	     mutex_unlock(_T), kernfs_node_lock(kn), struct kernfs_node *kn)

#endif	/* __KERNFS_INTERNAL_H */

Annotation

• Immediate include surface: `linux/lockdep.h`, `linux/fs.h`, `linux/mutex.h`, `linux/rwsem.h`, `linux/xattr.h`, `linux/kernfs.h`, `linux/fs_context.h`.
• Detected declarations: `struct kernfs_iattrs`, `struct kernfs_root`, `struct kernfs_super_info`, `function kernfs_root_is_locked`, `function kernfs_rename_is_locked`, `function kernfs_set_rev`, `function kernfs_inc_rev`, `function kernfs_dir_changed`.
• Atlas domain: Core OS / VFS And Filesystem Core.
• Implementation status: pattern implementation candidate.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

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.