// 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 * @dir: inode of expected parent * @name: expected name * @dentry: dentry to revalidate * @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 inode *dir, const struct qstr *name,				 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) {		struct inode *lower_dir = ecryptfs_inode_to_lower(dir);		struct name_snapshot n; 		take_dentry_name_snapshot(&n, lower_dentry);		rc = lower_dentry->d_op->d_revalidate(lower_dir, &n.name,						      lower_dentry, flags);		release_dentry_name_snapshot(&n);	} 	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;} /** * ecryptfs_d_release * @dentry: The ecryptfs dentry * * Called when a dentry is really deallocated. */static void ecryptfs_d_release(struct dentry *dentry){	dput(dentry->d_fsdata);} const struct dentry_operations ecryptfs_dops = {	.d_revalidate = ecryptfs_d_revalidate,	.d_release = ecryptfs_d_release,};