1 /* SPDX-License-Identifier: GPL-2.0-only */
4 * Copyright (C) 2011 Novell Inc.
5 * Copyright (C) 2016 Red Hat, Inc.
12 bool default_permissions;
15 const char *redirect_mode;
23 struct super_block *sb;
25 /* Unusable (conflicting) uuid */
27 /* Used as a lower layer (but maybe also as upper) */
33 /* Trap in ovl inode cache */
36 /* Index of this layer in fs root (upper idx == 0) */
38 /* One fsid per unique underlying sb (upper fsid == 0) */
43 const struct ovl_layer *layer;
44 struct dentry *dentry;
47 /* private information held for overlayfs's superblock */
49 struct vfsmount *upper_mnt;
50 unsigned int numlayer;
51 /* Number of unique fs among layers including upper fs */
53 const struct ovl_layer *layers;
55 /* workbasedir is the path at workdir= mount option */
56 struct dentry *workbasedir;
57 /* workdir is the 'work' directory under workbasedir */
58 struct dentry *workdir;
59 /* index directory listing overlay inodes by origin file handle */
60 struct dentry *indexdir;
62 /* pathnames of lower and upper dirs, for show_options */
63 struct ovl_config config;
64 /* creds of process who forced instantiation of super block */
65 const struct cred *creator_cred;
68 /* Did we take the inuse lock? */
71 /* Traps in ovl inode cache */
72 struct inode *upperdir_trap;
73 struct inode *workbasedir_trap;
74 struct inode *workdir_trap;
75 struct inode *indexdir_trap;
76 /* -1: disabled, 0: same fs, 1..32: number of unused ino bits */
80 static inline struct ovl_fs *OVL_FS(struct super_block *sb)
82 return (struct ovl_fs *)sb->s_fs_info;
85 /* private information held for every overlayfs dentry */
94 struct ovl_path lowerstack[];
97 struct ovl_entry *ovl_alloc_entry(unsigned int numlower);
99 static inline struct ovl_entry *OVL_E(struct dentry *dentry)
101 return (struct ovl_entry *) dentry->d_fsdata;
106 struct ovl_dir_cache *cache; /* directory */
107 struct inode *lowerdata; /* regular file */
109 const char *redirect;
112 struct inode vfs_inode;
113 struct dentry *__upperdentry;
116 /* synchronize copy up and more */
120 static inline struct ovl_inode *OVL_I(struct inode *inode)
122 return container_of(inode, struct ovl_inode, vfs_inode);
125 static inline struct dentry *ovl_upperdentry_dereference(struct ovl_inode *oi)
127 return READ_ONCE(oi->__upperdentry);