drop out of RCU in return_reval

... thus killing the need to handle drop-from-RCU in d_revalidate()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2011-02-15 01:35:28 -05:00
parent f5e1c1c1af
commit f60aef7ec6

View file

@ -571,25 +571,9 @@ void release_open_intent(struct nameidata *nd)
}
}
/*
* Call d_revalidate and handle filesystems that request rcu-walk
* to be dropped. This may be called and return in rcu-walk mode,
* regardless of success or error. If -ECHILD is returned, the caller
* must return -ECHILD back up the path walk stack so path walk may
* be restarted in ref-walk mode.
*/
static int d_revalidate(struct dentry *dentry, struct nameidata *nd)
static inline int d_revalidate(struct dentry *dentry, struct nameidata *nd)
{
int status;
status = dentry->d_op->d_revalidate(dentry, nd);
if (status == -ECHILD) {
if (nameidata_dentry_drop_rcu(nd, dentry))
return status;
status = dentry->d_op->d_revalidate(dentry, nd);
}
return status;
return dentry->d_op->d_revalidate(dentry, nd);
}
static struct dentry *
@ -617,7 +601,7 @@ do_revalidate(struct dentry *dentry, struct nameidata *nd)
static inline struct dentry *
do_revalidate_rcu(struct dentry *dentry, struct nameidata *nd)
{
int status = dentry->d_op->d_revalidate(dentry, nd);
int status = d_revalidate(dentry, nd);
if (likely(status > 0))
return dentry;
if (status == -ECHILD) {
@ -1517,12 +1501,15 @@ return_reval:
* We may need to check the cached dentry for staleness.
*/
if (need_reval_dot(nd->path.dentry)) {
if (nameidata_drop_rcu_last_maybe(nd))
return -ECHILD;
/* Note: we do not d_invalidate() */
err = d_revalidate(nd->path.dentry, nd);
if (!err)
err = -ESTALE;
if (err < 0)
break;
return 0;
}
return_base:
if (nameidata_drop_rcu_last_maybe(nd))