include/linux/fs.h

File Facts

System

Linux kernel

Corpus path

include/linux/fs.h

Extension

.h

Size

121836 bytes

Lines

3670

Domain

Core OS

Bucket

Core Kernel Interface

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.
• Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Allocates kernel memory; connect allocation flags and lifetime to context constraints.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/fs/super.h
• linux/vfsdebug.h
• linux/linkage.h
• linux/wait_bit.h
• linux/kdev_t.h
• linux/dcache.h
• linux/path.h
• linux/stat.h
• linux/cache.h
• linux/list.h
• linux/llist.h
• linux/radix-tree.h
• linux/xarray.h
• linux/rbtree.h
• linux/init.h
• linux/pid.h
• linux/bug.h
• linux/mutex.h
• linux/rwsem.h
• linux/mm_types.h
• linux/capability.h
• linux/semaphore.h
• linux/fcntl.h
• linux/rculist_bl.h
• linux/atomic.h
• linux/shrinker.h
• linux/migrate_mode.h
• linux/uidgid.h
• linux/lockdep.h
• linux/percpu-rwsem.h
• linux/workqueue.h
• linux/delayed_call.h

Detected Declarations

• struct bdi_writeback
• struct bio
• struct io_comp_batch
• struct fiemap_extent_info
• struct kiocb
• struct kobject
• struct pipe_inode_info
• struct poll_table_struct
• struct kstatfs
• struct vm_area_struct
• struct vfsmount
• struct cred
• struct swap_info_struct
• struct seq_file
• struct iov_iter
• struct fsnotify_mark_connector
• struct fs_context
• struct fs_parameter_spec
• struct file_kattr
• struct iomap_ops
• struct delegated_inode
• struct buffer_head
• struct iattr
• struct page
• struct address_space
• struct writeback_control
• struct readahead_control
• struct kiocb
• struct address_space_operations
• struct mapping_metadata_bhs
• struct address_space
• struct posix_acl
• struct inode_state_flags
• struct inode
• struct fown_struct
• struct file_ra_state
• struct file
• struct file_handle
• struct file_lock
• struct file_lease
• struct fasync_struct
• struct renamedata
• struct dir_context
• struct dir_context
• struct io_uring_cmd
• struct offset_ctx
• struct file_operations
• struct inode_operations

Annotated Snippet

const struct file_operations	*i_fop;	/* former ->i_op->default_file_ops */
		void (*free_inode)(struct inode *);
	};
	struct file_lock_context	*i_flctx;
	struct address_space	i_data;
	union {
		struct list_head	i_devices;
		int			i_linklen;
	};
	union {
		struct pipe_inode_info	*i_pipe;
		struct cdev		*i_cdev;
		char			*i_link;
		unsigned		i_dir_seq;
	};


#ifdef CONFIG_FSNOTIFY
	__u32			i_fsnotify_mask; /* all events this inode cares about */
	/* 32-bit hole reserved for expanding i_fsnotify_mask */
	struct fsnotify_mark_connector __rcu	*i_fsnotify_marks;
#endif

	void			*i_private; /* fs or device private pointer */
} __randomize_layout;

/*
 * i_state handling
 *
 * We hide all of it behind helpers so that we can validate consumers.
 */
static inline enum inode_state_flags_enum inode_state_read_once(struct inode *inode)
{
	return READ_ONCE(inode->i_state.__state);
}

static inline enum inode_state_flags_enum inode_state_read(struct inode *inode)
{
	lockdep_assert_held(&inode->i_lock);
	return inode->i_state.__state;
}

static inline void inode_state_set_raw(struct inode *inode,
				       enum inode_state_flags_enum flags)
{
	WRITE_ONCE(inode->i_state.__state, inode->i_state.__state | flags);
}

static inline void inode_state_set(struct inode *inode,
				   enum inode_state_flags_enum flags)
{
	lockdep_assert_held(&inode->i_lock);
	inode_state_set_raw(inode, flags);
}

static inline void inode_state_clear_raw(struct inode *inode,
					 enum inode_state_flags_enum flags)
{
	WRITE_ONCE(inode->i_state.__state, inode->i_state.__state & ~flags);
}

static inline void inode_state_clear(struct inode *inode,
				     enum inode_state_flags_enum flags)
{
	lockdep_assert_held(&inode->i_lock);
	inode_state_clear_raw(inode, flags);
}

static inline void inode_state_assign_raw(struct inode *inode,
					  enum inode_state_flags_enum flags)
{
	WRITE_ONCE(inode->i_state.__state, flags);
}

static inline void inode_state_assign(struct inode *inode,
				      enum inode_state_flags_enum flags)
{
	lockdep_assert_held(&inode->i_lock);
	inode_state_assign_raw(inode, flags);
}

static inline void inode_state_replace_raw(struct inode *inode,
					   enum inode_state_flags_enum clearflags,
					   enum inode_state_flags_enum setflags)
{
	enum inode_state_flags_enum flags;
	flags = inode->i_state.__state;
	flags &= ~clearflags;
	flags |= setflags;
	inode_state_assign_raw(inode, flags);

Annotation

• Immediate include surface: `linux/fs/super.h`, `linux/vfsdebug.h`, `linux/linkage.h`, `linux/wait_bit.h`, `linux/kdev_t.h`, `linux/dcache.h`, `linux/path.h`, `linux/stat.h`.
• Detected declarations: `struct bdi_writeback`, `struct bio`, `struct io_comp_batch`, `struct fiemap_extent_info`, `struct kiocb`, `struct kobject`, `struct pipe_inode_info`, `struct poll_table_struct`, `struct kstatfs`, `struct vm_area_struct`.
• Atlas domain: Core OS / Core Kernel Interface.
• Implementation status: pattern implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
• 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.