/**
* 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>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
* 02111-1307, USA.
*/
#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;
if (!(lower_dentry->d_flags & DCACHE_OP_REVALIDATE))
return 1;
if (flags & LOOKUP_RCU)
return -ECHILD;
rc = lower_dentry->d_op->d_revalidate(lower_dentry, flags);
if (dentry->d_inode) {
struct inode *lower_inode =
ecryptfs_inode_to_lower(dentry->d_inode);
fsstack_copy_attr_all(dentry->d_inode, lower_inode);
}
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,
};
