// SPDX-License-Identifier: GPL-2.0-or-later/* * eCryptfs: Linux filesystem encryption layer * * Copyright (C) 1997-2003 Erez Zadok * Copyright (C) 2001-2003 Stony Brook University * Copyright (C) 2004-2006 International Business Machines Corp. *   Author(s): Michael A. Halcrow <mahalcro@us.ibm.com> */ #include <linux/dcache.h>#include <linux/namei.h>#include <linux/mount.h>#include <linux/fs_stack.h>#include <linux/slab.h>#include "ecryptfs_kernel.h" /** * ecryptfs_d_revalidate - revalidate an ecryptfs dentry * @dentry: The ecryptfs dentry * @flags: lookup flags * * Called when the VFS needs to revalidate a dentry. This * is called whenever a name lookup finds a dentry in the * dcache. Most filesystems leave this as NULL, because all their * dentries in the dcache are valid. * * Returns 1 if valid, 0 otherwise. * */static int ecryptfs_d_revalidate(struct dentry *dentry, unsigned int flags){	struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);	int rc = 1; 	if (flags & LOOKUP_RCU)		return -ECHILD; 	if (lower_dentry->d_flags & DCACHE_OP_REVALIDATE)		rc = lower_dentry->d_op->d_revalidate(lower_dentry, flags); 	if (d_really_is_positive(dentry)) {		struct inode *inode = d_inode(dentry); 		fsstack_copy_attr_all(inode, ecryptfs_inode_to_lower(inode));		if (!inode->i_nlink)			return 0;	}	return rc;} struct kmem_cache *ecryptfs_dentry_info_cache; static void ecryptfs_dentry_free_rcu(struct rcu_head *head){	kmem_cache_free(ecryptfs_dentry_info_cache,		container_of(head, struct ecryptfs_dentry_info, rcu));} /** * ecryptfs_d_release * @dentry: The ecryptfs dentry * * Called when a dentry is really deallocated. */static void ecryptfs_d_release(struct dentry *dentry){	struct ecryptfs_dentry_info *p = dentry->d_fsdata;	if (p) {		path_put(&p->lower_path);		call_rcu(&p->rcu, ecryptfs_dentry_free_rcu);	}} const struct dentry_operations ecryptfs_dops = {	.d_revalidate = ecryptfs_d_revalidate,	.d_release = ecryptfs_d_release,};