blob: 36b49bd09264a5bd92df902a1de7d10771d4b770 [file] [log] [blame]
* Copyright (C) 2011 Novell Inc.
* Copyright (C) 2016 Red Hat, Inc.
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
struct ovl_config {
char *lowerdir;
char *upperdir;
char *workdir;
bool default_permissions;
bool redirect_dir;
bool index;
/* private information held for overlayfs's superblock */
struct ovl_fs {
struct vfsmount *upper_mnt;
unsigned numlower;
struct vfsmount **lower_mnt;
/* workbasedir is the path at workdir= mount option */
struct dentry *workbasedir;
/* workdir is the 'work' directory under workbasedir */
struct dentry *workdir;
/* index directory listing overlay inodes by origin file handle */
struct dentry *indexdir;
long namelen;
/* pathnames of lower and upper dirs, for show_options */
struct ovl_config config;
/* creds of process who forced instantiation of super block */
const struct cred *creator_cred;
bool tmpfile;
bool noxattr;
/* sb common to all layers */
struct super_block *same_sb;
/* Did we take the inuse lock? */
bool upperdir_locked;
bool workdir_locked;
/* private information held for every overlayfs dentry */
struct ovl_entry {
union {
struct {
unsigned long has_upper;
bool opaque;
struct rcu_head rcu;
unsigned numlower;
struct path lowerstack[];
struct ovl_entry *ovl_alloc_entry(unsigned int numlower);
struct ovl_inode {
struct ovl_dir_cache *cache;
const char *redirect;
u64 version;
unsigned long flags;
struct inode vfs_inode;
struct dentry *__upperdentry;
struct inode *lower;
/* synchronize copy up and more */
struct mutex lock;
static inline struct ovl_inode *OVL_I(struct inode *inode)
return container_of(inode, struct ovl_inode, vfs_inode);
static inline struct dentry *ovl_upperdentry_dereference(struct ovl_inode *oi)
return READ_ONCE(oi->__upperdentry);