diff options
Diffstat (limited to 'fs/overlayfs/ovl_entry.h')
| -rw-r--r-- | fs/overlayfs/ovl_entry.h | 107 |
1 files changed, 77 insertions, 30 deletions
diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h index e1af8f660698..1d4828dbcf7a 100644 --- a/fs/overlayfs/ovl_entry.h +++ b/fs/overlayfs/ovl_entry.h @@ -6,15 +6,14 @@ */ struct ovl_config { - char *lowerdir; char *upperdir; char *workdir; + char **lowerdirs; bool default_permissions; - bool redirect_dir; - bool redirect_follow; - const char *redirect_mode; + int redirect_mode; + int verity_mode; bool index; - bool uuid; + int uuid; bool nfs_export; int xino; bool metacopy; @@ -32,6 +31,7 @@ struct ovl_sb { }; struct ovl_layer { + /* ovl_free_fs() relies on @mnt being the first member! */ struct vfsmount *mnt; /* Trap in ovl inode cache */ struct inode *trap; @@ -40,6 +40,8 @@ struct ovl_layer { int idx; /* One fsid per unique underlying sb (upper fsid == 0) */ int fsid; + /* xwhiteouts were found on this layer */ + bool has_xwhiteouts; }; struct ovl_path { @@ -47,19 +49,24 @@ struct ovl_path { struct dentry *dentry; }; +struct ovl_entry { + unsigned int __numlower; + struct ovl_path __lowerstack[] __counted_by(__numlower); +}; + /* private information held for overlayfs's superblock */ struct ovl_fs { unsigned int numlayer; /* Number of unique fs among layers including upper fs */ unsigned int numfs; - const struct ovl_layer *layers; + /* Number of data-only lower layers */ + unsigned int numdatalayer; + struct ovl_layer *layers; struct ovl_sb *fs; /* workbasedir is the path at workdir= mount option */ struct dentry *workbasedir; - /* workdir is the 'work' directory under workbasedir */ + /* workdir is the 'work' or 'index' 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; @@ -67,36 +74,49 @@ struct ovl_fs { const struct cred *creator_cred; bool tmpfile; bool noxattr; + bool nofh; /* Did we take the inuse lock? */ bool upperdir_locked; bool workdir_locked; - bool share_whiteout; /* Traps in ovl inode cache */ struct inode *workbasedir_trap; struct inode *workdir_trap; - struct inode *indexdir_trap; /* -1: disabled, 0: same fs, 1..32: number of unused ino bits */ int xino_mode; /* For allocation of non-persistent inode numbers */ atomic_long_t last_ino; - /* Whiteout dentry cache */ + /* Shared whiteout cache */ struct dentry *whiteout; + bool no_shared_whiteout; + struct mutex whiteout_lock; /* r/o snapshot of upperdir sb's only taken on volatile mounts */ errseq_t errseq; + bool casefold; }; +/* Number of lower layers, not including data-only layers */ +static inline unsigned int ovl_numlowerlayer(struct ovl_fs *ofs) +{ + return ofs->numlayer - ofs->numdatalayer - 1; +} + static inline struct vfsmount *ovl_upper_mnt(struct ovl_fs *ofs) { return ofs->layers[0].mnt; } -static inline struct user_namespace *ovl_upper_mnt_userns(struct ovl_fs *ofs) +static inline struct mnt_idmap *ovl_upper_mnt_idmap(struct ovl_fs *ofs) { - return mnt_user_ns(ovl_upper_mnt(ofs)); + return mnt_idmap(ovl_upper_mnt(ofs)); } +extern struct file_system_type ovl_fs_type; + static inline struct ovl_fs *OVL_FS(struct super_block *sb) { + if (IS_ENABLED(CONFIG_OVERLAY_FS_DEBUG)) + WARN_ON_ONCE(sb->s_type != &ovl_fs_type); + return (struct ovl_fs *)sb->s_fs_info; } @@ -105,36 +125,53 @@ static inline bool ovl_should_sync(struct ovl_fs *ofs) return !ofs->config.ovl_volatile; } -/* private information held for every overlayfs dentry */ -struct ovl_entry { - union { - struct { - unsigned long flags; - }; - struct rcu_head rcu; - }; - unsigned numlower; - struct ovl_path lowerstack[]; -}; +static inline unsigned int ovl_numlower(struct ovl_entry *oe) +{ + return oe ? oe->__numlower : 0; +} -struct ovl_entry *ovl_alloc_entry(unsigned int numlower); +static inline struct ovl_path *ovl_lowerstack(struct ovl_entry *oe) +{ + return ovl_numlower(oe) ? oe->__lowerstack : NULL; +} -static inline struct ovl_entry *OVL_E(struct dentry *dentry) +static inline struct ovl_path *ovl_lowerpath(struct ovl_entry *oe) { - return (struct ovl_entry *) dentry->d_fsdata; + return ovl_lowerstack(oe); +} + +static inline struct ovl_path *ovl_lowerdata(struct ovl_entry *oe) +{ + struct ovl_path *lowerstack = ovl_lowerstack(oe); + + return lowerstack ? &lowerstack[oe->__numlower - 1] : NULL; +} + +/* May return NULL if lazy lookup of lowerdata is needed */ +static inline struct dentry *ovl_lowerdata_dentry(struct ovl_entry *oe) +{ + struct ovl_path *lowerdata = ovl_lowerdata(oe); + + return lowerdata ? READ_ONCE(lowerdata->dentry) : NULL; +} + +/* private information held for every overlayfs dentry */ +static inline unsigned long *OVL_E_FLAGS(struct dentry *dentry) +{ + return (unsigned long *) &dentry->d_fsdata; } struct ovl_inode { union { struct ovl_dir_cache *cache; /* directory */ - struct inode *lowerdata; /* regular file */ + const char *lowerdata_redirect; /* regular file */ }; const char *redirect; u64 version; unsigned long flags; struct inode vfs_inode; struct dentry *__upperdentry; - struct ovl_path lowerpath; + struct ovl_entry *oe; /* synchronize copy up and more */ struct mutex lock; @@ -145,6 +182,16 @@ static inline struct ovl_inode *OVL_I(struct inode *inode) return container_of(inode, struct ovl_inode, vfs_inode); } +static inline struct ovl_entry *OVL_I_E(struct inode *inode) +{ + return inode ? OVL_I(inode)->oe : NULL; +} + +static inline struct ovl_entry *OVL_E(struct dentry *dentry) +{ + return OVL_I_E(d_inode(dentry)); +} + static inline struct dentry *ovl_upperdentry_dereference(struct ovl_inode *oi) { return READ_ONCE(oi->__upperdentry); |