94 строки
2.1 KiB
C
94 строки
2.1 KiB
C
/*
|
|
*
|
|
* 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 redirect_follow;
|
|
const char *redirect_mode;
|
|
bool index;
|
|
};
|
|
|
|
struct ovl_layer {
|
|
struct vfsmount *mnt;
|
|
dev_t pseudo_dev;
|
|
};
|
|
|
|
struct ovl_path {
|
|
struct ovl_layer *layer;
|
|
struct dentry *dentry;
|
|
};
|
|
|
|
/* private information held for overlayfs's superblock */
|
|
struct ovl_fs {
|
|
struct vfsmount *upper_mnt;
|
|
unsigned numlower;
|
|
struct ovl_layer *lower_layers;
|
|
/* 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 ovl_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);
|
|
}
|