/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_NAMEI_H #define _LINUX_NAMEI_H #include #include #include #include enum { MAX_NESTED_LINKS = 8 }; #define MAXSYMLINKS 40 /* * Type of the last component on LOOKUP_PARENT */ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND}; /* * The bitmask for a lookup event: * - follow links at the end * - require a directory * - ending slashes ok even for nonexistent files * - internal "there are more path components" flag * - dentry cache is untrusted; force a real lookup * - suppress terminal automount */ #define LOOKUP_FOLLOW 0x0001 #define LOOKUP_DIRECTORY 0x0002 #define LOOKUP_AUTOMOUNT 0x0004 #define LOOKUP_PARENT 0x0010 #define LOOKUP_REVAL 0x0020 #define LOOKUP_RCU 0x0040 #define LOOKUP_NO_REVAL 0x0080 /* * Intent data */ #define LOOKUP_OPEN 0x0100 #define LOOKUP_CREATE 0x0200 #define LOOKUP_EXCL 0x0400 #define LOOKUP_RENAME_TARGET 0x0800 #define LOOKUP_JUMPED 0x1000 #define LOOKUP_ROOT 0x2000 #define LOOKUP_EMPTY 0x4000 #define LOOKUP_DOWN 0x8000 extern int path_pts(struct path *path); extern int user_path_at_empty(int, const char __user *, unsigned, struct path *, int *empty); static inline int user_path_at(int dfd, const char __user *name, unsigned flags, struct path *path) { return user_path_at_empty(dfd, name, flags, path, NULL); } static inline int user_path(const char __user *name, struct path *path) { return user_path_at_empty(AT_FDCWD, name, LOOKUP_FOLLOW, path, NULL); } static inline int user_lpath(const char __user *name, struct path *path) { return user_path_at_empty(AT_FDCWD, name, 0, path, NULL); } static inline int user_path_dir(const char __user *name, struct path *path) { return user_path_at_empty(AT_FDCWD, name, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, path, NULL); } extern int kern_path(const char *, unsigned, struct path *); extern struct dentry *kern_path_create(int, const char *, struct path *, unsigned int); extern struct dentry *user_path_create(int, const char __user *, struct path *, unsigned int); extern void done_path_create(struct path *, struct dentry *); extern struct dentry *kern_path_locked(const char *, struct path *); extern int vfs_path_lookup(struct dentry *, struct vfsmount *, const char *, unsigned int, struct path *); extern int kern_path_mountpoint(int, const char *, struct path *, unsigned int); extern struct dentry *try_lookup_one_len(const char *, struct dentry *, int); extern struct dentry *lookup_one_len(const char *, struct dentry *, int); extern struct dentry *lookup_one_len2(const char *, struct vfsmount *mnt, struct dentry *, int); extern struct dentry *lookup_one_len_unlocked(const char *, struct dentry *, int); extern int follow_down_one(struct path *); extern int follow_down(struct path *); extern int follow_up(struct path *); extern struct dentry *lock_rename(struct dentry *, struct dentry *); extern void unlock_rename(struct dentry *, struct dentry *); extern void nd_jump_link(struct path *path); static inline void nd_terminate_link(void *name, size_t len, size_t maxlen) { ((char *) name)[min(len, maxlen)] = '\0'; } /** * retry_estale - determine whether the caller should retry an operation * @error: the error that would currently be returned * @flags: flags being used for next lookup attempt * * Check to see if the error code was -ESTALE, and then determine whether * to retry the call based on whether "flags" already has LOOKUP_REVAL set. * * Returns true if the caller should try the operation again. */ static inline bool retry_estale(const long error, const unsigned int flags) { return error == -ESTALE && !(flags & LOOKUP_REVAL); } #endif /* _LINUX_NAMEI_H */