Commit 7e4745a0 authored by Al Viro's avatar Al Viro
Browse files

switch try_to_unlazy_next() to __legitimize_mnt() 



The tricky case (__legitimize_mnt() failing after having grabbed
a reference) can be trivially dealt with by leaving nd->path.mnt
non-NULL, for terminate_walk() to drop it.

legitimize_mnt() becomes static after that.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 51c6546c

fs/mount.h

+0 −1
Original line number Diff line number Diff line
@@ -100,7 +100,6 @@ static inline int is_mounted(struct vfsmount *mnt) 
extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *);



extern int __legitimize_mnt(struct vfsmount *, unsigned);

extern bool legitimize_mnt(struct vfsmount *, unsigned);



static inline bool __path_is_mountpoint(const struct path *path)

{

fs/namei.c

+7 −2
Original line number Diff line number Diff line
@@ -799,13 +799,18 @@ static bool try_to_unlazy(struct nameidata *nd) 
 */

static bool try_to_unlazy_next(struct nameidata *nd, struct dentry *dentry, unsigned seq)

{

	int res;

	BUG_ON(!(nd->flags & LOOKUP_RCU));



	nd->flags &= ~LOOKUP_RCU;

	if (unlikely(!legitimize_links(nd)))

		goto out2;

	if (unlikely(!legitimize_mnt(nd->path.mnt, nd->m_seq)))

	res = __legitimize_mnt(nd->path.mnt, nd->m_seq);

	if (unlikely(res)) {

		if (res > 0)

			goto out2;

		goto out1;

	}

	if (unlikely(!lockref_get_not_dead(&nd->path.dentry->d_lockref)))

		goto out1;

fs/namespace.c

+1 −1
Original line number Diff line number Diff line
@@ -648,7 +648,7 @@ int __legitimize_mnt(struct vfsmount *bastard, unsigned seq) 
}



/* call under rcu_read_lock */

bool legitimize_mnt(struct vfsmount *bastard, unsigned seq)

static bool legitimize_mnt(struct vfsmount *bastard, unsigned seq)

{

	int res = __legitimize_mnt(bastard, seq);

	if (likely(!res))