mirror of https://gitee.com/openkylin/linux.git
79 lines
2.0 KiB
C
79 lines
2.0 KiB
C
// 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,
|
|
};
|