139 lines
5.5 KiB
C
139 lines
5.5 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _LINUX_NAMEI_H
|
|
#define _LINUX_NAMEI_H
|
|
|
|
#include <linux/fs.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/path.h>
|
|
#include <linux/fcntl.h>
|
|
#include <linux/errno.h>
|
|
|
|
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};
|
|
|
|
/* pathwalk mode */
|
|
#define LOOKUP_FOLLOW 0x0001 /* follow links at the end */
|
|
#define LOOKUP_DIRECTORY 0x0002 /* require a directory */
|
|
#define LOOKUP_AUTOMOUNT 0x0004 /* force terminal automount */
|
|
#define LOOKUP_EMPTY 0x4000 /* accept empty path [user_... only] */
|
|
#define LOOKUP_DOWN 0x8000 /* follow mounts in the starting point */
|
|
#define LOOKUP_MOUNTPOINT 0x0080 /* follow mounts in the end */
|
|
|
|
#define LOOKUP_REVAL 0x0020 /* tell ->d_revalidate() to trust no cache */
|
|
#define LOOKUP_RCU 0x0040 /* RCU pathwalk mode; semi-internal */
|
|
|
|
/* These tell filesystem methods that we are dealing with the final component... */
|
|
#define LOOKUP_OPEN 0x0100 /* ... in open */
|
|
#define LOOKUP_CREATE 0x0200 /* ... in object creation */
|
|
#define LOOKUP_EXCL 0x0400 /* ... in exclusive creation */
|
|
#define LOOKUP_RENAME_TARGET 0x0800 /* ... in destination of rename() */
|
|
|
|
/* internal use only */
|
|
#define LOOKUP_PARENT 0x0010
|
|
|
|
/* Scoping flags for lookup. */
|
|
#define LOOKUP_NO_SYMLINKS 0x010000 /* No symlink crossing. */
|
|
#define LOOKUP_NO_MAGICLINKS 0x020000 /* No nd_jump_link() crossing. */
|
|
#define LOOKUP_NO_XDEV 0x040000 /* No mountpoint crossing. */
|
|
#define LOOKUP_BENEATH 0x080000 /* No escaping from starting point. */
|
|
#define LOOKUP_IN_ROOT 0x100000 /* Treat dirfd as fs root. */
|
|
#define LOOKUP_CACHED 0x200000 /* Only do cached lookup */
|
|
#define LOOKUP_LINKAT_EMPTY 0x400000 /* Linkat request with empty path. */
|
|
/* LOOKUP_* flags which do scope-related checks based on the dirfd. */
|
|
#define LOOKUP_IS_SCOPED (LOOKUP_BENEATH | LOOKUP_IN_ROOT)
|
|
|
|
extern int path_pts(struct path *path);
|
|
|
|
extern int user_path_at(int, const char __user *, unsigned, struct path *);
|
|
|
|
struct dentry *lookup_one_qstr_excl(const struct qstr *name,
|
|
struct dentry *base,
|
|
unsigned int flags);
|
|
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 struct dentry *user_path_locked_at(int , const char __user *, struct path *);
|
|
int vfs_path_parent_lookup(struct filename *filename, unsigned int flags,
|
|
struct path *parent, struct qstr *last, int *type,
|
|
const struct path *root);
|
|
int vfs_path_lookup(struct dentry *, struct vfsmount *, const char *,
|
|
unsigned int, struct path *);
|
|
|
|
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_len_unlocked(const char *, struct dentry *, int);
|
|
extern struct dentry *lookup_positive_unlocked(const char *, struct dentry *, int);
|
|
struct dentry *lookup_one(struct mnt_idmap *, const char *, struct dentry *, int);
|
|
struct dentry *lookup_one_unlocked(struct mnt_idmap *idmap,
|
|
const char *name, struct dentry *base,
|
|
int len);
|
|
struct dentry *lookup_one_positive_unlocked(struct mnt_idmap *idmap,
|
|
const char *name,
|
|
struct dentry *base, int len);
|
|
|
|
extern int follow_down_one(struct path *);
|
|
extern int follow_down(struct path *path, unsigned int flags);
|
|
extern int follow_up(struct path *);
|
|
|
|
extern struct dentry *lock_rename(struct dentry *, struct dentry *);
|
|
extern struct dentry *lock_rename_child(struct dentry *, struct dentry *);
|
|
extern void unlock_rename(struct dentry *, struct dentry *);
|
|
|
|
/**
|
|
* mode_strip_umask - handle vfs umask stripping
|
|
* @dir: parent directory of the new inode
|
|
* @mode: mode of the new inode to be created in @dir
|
|
*
|
|
* In most filesystems, umask stripping depends on whether or not the
|
|
* filesystem supports POSIX ACLs. If the filesystem doesn't support it umask
|
|
* stripping is done directly in here. If the filesystem does support POSIX
|
|
* ACLs umask stripping is deferred until the filesystem calls
|
|
* posix_acl_create().
|
|
*
|
|
* Some filesystems (like NFSv4) also want to avoid umask stripping by the
|
|
* VFS, but don't support POSIX ACLs. Those filesystems can set SB_I_NOUMASK
|
|
* to get this effect without declaring that they support POSIX ACLs.
|
|
*
|
|
* Returns: mode
|
|
*/
|
|
static inline umode_t __must_check mode_strip_umask(const struct inode *dir, umode_t mode)
|
|
{
|
|
if (!IS_POSIXACL(dir) && !(dir->i_sb->s_iflags & SB_I_NOUMASK))
|
|
mode &= ~current_umask();
|
|
return mode;
|
|
}
|
|
|
|
extern int __must_check nd_jump_link(const 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 unlikely(error == -ESTALE && !(flags & LOOKUP_REVAL));
|
|
}
|
|
|
|
#endif /* _LINUX_NAMEI_H */
|