Linux Filesystems API

Table of Contents

1. The Linux VFS

The Filesystem types

enum positive_aop_returns — aop return codes with specific semantics

struct export_operations — for nfsd to communicate with file systems

The Directory Cache

d_invalidate — invalidate a dentry

shrink_dcache_sb — shrink dcache for a superblock

have_submounts — check for mounts over a dentry

shrink_dcache_parent — prune dcache

d_alloc — allocate a dcache entry

d_instantiate — fill in inode information for a dentry

d_alloc_root — allocate root dentry

d_alloc_anon — allocate an anonymous dentry

d_splice_alias — splice a disconnected dentry into the tree if one exists

d_lookup — search for a dentry

d_validate — verify dentry provided from insecure source

d_delete — delete a dentry

d_rehash — add an entry back to the hash

d_move — move a dentry

d_materialise_unique — introduce an inode into the tree

find_inode_number — check for dentry with name

__d_drop — drop a dentry

d_add — add dentry to hash queues

d_add_unique — add dentry to hash queues without aliasing

dget — get a reference to a dentry

d_unhashed — is dentry hashed

Inode Handling

clear_inode — clear an inode

invalidate_inodes — discard the inodes on a device

new_inode — obtain an inode

iunique — get a unique inode number

ilookup5_nowait — search for an inode in the inode cache

ilookup5 — search for an inode in the inode cache

ilookup — search for an inode in the inode cache

iget5_locked — obtain an inode from a mounted file system

iget_locked — obtain an inode from a mounted file system

__insert_inode_hash — hash an inode

remove_inode_hash — remove an inode from the hash

iput — put an inode

bmap — find a block number in a file

touch_atime — update the access time

file_update_time — update mtime and ctime time

make_bad_inode — mark an inode bad due to an I/O error

is_bad_inode — is an inode errored

Registration and Superblocks

deactivate_super — drop an active reference to superblock

generic_shutdown_super — common helper for ->kill_sb

sget — find or create a superblock

get_super — get the superblock of a device

File Locks

posix_lock_file — Apply a POSIX-style lock to a file

posix_lock_file_conf — Apply a POSIX-style lock to a file

posix_lock_file_wait — Apply a POSIX-style lock to a file

locks_mandatory_area — Check for a conflicting lock

__break_lease — revoke all outstanding leases on file

lease_get_mtime —

flock_lock_file_wait — Apply a FLOCK-style lock to a file

posix_unblock_lock — stop waiting for a file lock

lock_may_read — checks that the region is free of locks

lock_may_write — checks that the region is free of locks

locks_mandatory_locked — Check for an active lock

fcntl_getlease — Enquire what lease is currently active

__setlease — sets a lease on an open file

fcntl_setlease — sets a lease on an open file

sys_flock — flock system call.

get_locks_status — reports lock usage in /proc/locks

Other Functions

mpage_readpages — populate an address space with some pages, and

mpage_writepages — walk the list of dirty pages of the given

generic_permission — check for access rights on a Posix-like filesystem

vfs_permission — check for access rights to a given path

file_permission — check for additional access rights to a given file

lookup_create — lookup a dentry, creating it if it doesn't exist

freeze_bdev — - lock a filesystem and force it into a consistent state

thaw_bdev — - unlock filesystem

sync_mapping_buffers — write out and wait upon a mapping's “associated”

mark_buffer_dirty — mark a buffer_head as needing writeout

__bread — reads a specified block and returns the bh

block_invalidatepage — invalidate part of all of a buffer-backed page

ll_rw_block — level access to block devices (DEPRECATED)

bio_alloc_bioset — allocate a bio for I/O

bio_put — release a reference to a bio

__bio_clone — clone a bio

bio_clone — clone a bio

bio_get_nr_vecs — return approx number of vecs

bio_add_pc_page — attempt to add page to bio

bio_add_page — attempt to add page to bio

bio_uncopy_user — finish previously mapped bio

bio_copy_user — copy user data to bio

bio_map_user — map user address into bio

bio_unmap_user — unmap a bio

bio_map_kern — map kernel address into bio

bio_endio — end I/O on a bio

seq_open — initialize sequential file

seq_read — ->read method for sequential files.

seq_lseek — ->llseek method for sequential files.

seq_release — free the structures associated with sequential file.

seq_escape — print string into buffer, escaping some characters

register_filesystem — register a new filesystem

unregister_filesystem — unregister a file system

__mark_inode_dirty — internal function

write_inode_now — write an inode to disk

sync_inode — write an inode and its pages to disk.

generic_osync_inode — flush all dirty data for a given inode to disk

bd_claim_by_disk — wrapper function for bd_claim_by_kobject

bd_release_from_disk — wrapper function for bd_release_from_kobject

open_bdev_excl — open a block device by name and set it up for use

close_bdev_excl — release a blockdevice openen by open_bdev_excl

2. The proc filesystem

sysctl interface

register_sysctl_table — register a sysctl hierarchy

unregister_sysctl_table — unregister a sysctl table hierarchy

proc_dostring — read a string sysctl

proc_dointvec — read a vector of integers

proc_dointvec_minmax — read a vector of integers with min/max values

proc_doulongvec_minmax — read a vector of long integers with min/max values

proc_doulongvec_ms_jiffies_minmax — read a vector of millisecond values with min/max values

proc_dointvec_jiffies — read a vector of integers as seconds

proc_dointvec_userhz_jiffies — read a vector of integers as 1/USER_HZ seconds

proc_dointvec_ms_jiffies — read a vector of integers as 1 milliseconds

proc filesystem interface

proc_flush_task — Remove dcache entries for task from the /proc dcache.

3. The Filesystem for Exporting Kernel Objects

sysfs_create_file — create an attribute file for an object.

sysfs_update_file — update the modified timestamp on an object attribute.

sysfs_chmod_file — update the modified mode value on an object attribute.

sysfs_remove_file — remove an object attribute.

sysfs_create_link — create symlink between two objects.

sysfs_remove_link — remove symlink in object's directory.

sysfs_create_bin_file — create binary file for object.

sysfs_remove_bin_file — remove binary file for object.

4. The debugfs filesystem

debugfs interface

debugfs_create_file — create a file in the debugfs filesystem

debugfs_create_dir — create a directory in the debugfs filesystem

debugfs_remove — removes a file or directory from the debugfs filesystem

debugfs_create_u8 — create a debugfs file that is used to read and write an unsigned 8-bit value

debugfs_create_u16 — create a debugfs file that is used to read and write an unsigned 16-bit value

debugfs_create_u32 — create a debugfs file that is used to read and write an unsigned 32-bit value

debugfs_create_bool — create a debugfs file that is used to read and write a boolean value

debugfs_create_blob — create a debugfs file that is used to read and write a binary blob

5. The Linux Journalling API

Overview

Details

Summary

Data Types

Structures

Functions

Journal Level

Transasction Level

See also