diff options
Diffstat (limited to 'include/linux/namei.h')
| -rw-r--r-- | include/linux/namei.h | 111 |
1 files changed, 73 insertions, 38 deletions
diff --git a/include/linux/namei.h b/include/linux/namei.h index a4bb992623c4..5d085428e471 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -18,67 +18,102 @@ enum { MAX_NESTED_LINKS = 8 }; 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 */ +#define LOOKUP_FOLLOW BIT(0) /* follow links at the end */ +#define LOOKUP_DIRECTORY BIT(1) /* require a directory */ +#define LOOKUP_AUTOMOUNT BIT(2) /* force terminal automount */ +#define LOOKUP_EMPTY BIT(3) /* accept empty path [user_... only] */ +#define LOOKUP_LINKAT_EMPTY BIT(4) /* Linkat request with empty path. */ +#define LOOKUP_DOWN BIT(5) /* follow mounts in the starting point */ +#define LOOKUP_MOUNTPOINT BIT(6) /* follow mounts in the end */ +#define LOOKUP_REVAL BIT(7) /* tell ->d_revalidate() to trust no cache */ +#define LOOKUP_RCU BIT(8) /* RCU pathwalk mode; semi-internal */ +#define LOOKUP_CACHED BIT(9) /* Only do cached lookup */ +#define LOOKUP_PARENT BIT(10) /* Looking up final parent in path */ +/* 5 spare bits for pathwalk */ /* 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() */ +#define LOOKUP_OPEN BIT(16) /* ... in open */ +#define LOOKUP_CREATE BIT(17) /* ... in object creation */ +#define LOOKUP_EXCL BIT(18) /* ... in target must not exist */ +#define LOOKUP_RENAME_TARGET BIT(19) /* ... in destination of rename() */ -/* internal use only */ -#define LOOKUP_PARENT 0x0010 -#define LOOKUP_JUMPED 0x1000 -#define LOOKUP_ROOT 0x2000 -#define LOOKUP_ROOT_GRABBED 0x0008 +/* 4 spare bits for intent */ /* 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_NO_SYMLINKS BIT(24) /* No symlink crossing. */ +#define LOOKUP_NO_MAGICLINKS BIT(25) /* No nd_jump_link() crossing. */ +#define LOOKUP_NO_XDEV BIT(26) /* No mountpoint crossing. */ +#define LOOKUP_BENEATH BIT(27) /* No escaping from starting point. */ +#define LOOKUP_IN_ROOT BIT(28) /* Treat dirfd as fs root. */ /* LOOKUP_* flags which do scope-related checks based on the dirfd. */ #define LOOKUP_IS_SCOPED (LOOKUP_BENEATH | LOOKUP_IN_ROOT) +/* 3 spare bits for scoping */ 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); -} +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 *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); +extern struct dentry *kern_path_locked_negative(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_noperm(struct qstr *, struct dentry *); +extern struct dentry *lookup_noperm(struct qstr *, struct dentry *); +extern struct dentry *lookup_noperm_unlocked(struct qstr *, struct dentry *); +extern struct dentry *lookup_noperm_positive_unlocked(struct qstr *, struct dentry *); +struct dentry *lookup_one(struct mnt_idmap *, struct qstr *, struct dentry *); +struct dentry *lookup_one_unlocked(struct mnt_idmap *idmap, + struct qstr *name, struct dentry *base); +struct dentry *lookup_one_positive_unlocked(struct mnt_idmap *idmap, + struct qstr *name, + struct dentry *base); extern int follow_down_one(struct path *); -extern int follow_down(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 *); -extern int __must_check nd_jump_link(struct path *path); +/** + * 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) { @@ -98,7 +133,7 @@ static inline void nd_terminate_link(void *name, size_t len, size_t maxlen) static inline bool retry_estale(const long error, const unsigned int flags) { - return error == -ESTALE && !(flags & LOOKUP_REVAL); + return unlikely(error == -ESTALE && !(flags & LOOKUP_REVAL)); } #endif /* _LINUX_NAMEI_H */ |