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>
diff --git a/fs/namei.c b/fs/namei.c
index a98f7f1..10635d3 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -571,25 +571,9 @@
}
}
-/*
- * 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 @@
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 @@
* 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))