stash_dentry
struct dentry *(*stash_dentry)(struct dentry **stashed,
struct dentry *stash_dentry(struct dentry **stashed, struct dentry *dentry);
if (sops->stash_dentry)
res = sops->stash_dentry(stashed, dentry);
res = stash_dentry(stashed, dentry);
return stash_dentry(stashed, dentry);
.stash_dentry = pidfs_stash_dentry,