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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/**
2 * eCryptfs: Linux filesystem encryption layer
3 *
4 * Copyright (C) 1997-2003 Erez Zadok
5 * Copyright (C) 2001-2003 Stony Brook University
6 * Copyright (C) 2004-2006 International Business Machines Corp.
7 * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation; either version 2 of the
12 * License, or (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
22 * 02111-1307, USA.
23 */
24
25#include <linux/dcache.h>
26#include <linux/namei.h>
27#include "ecryptfs_kernel.h"
28
29/**
30 * ecryptfs_d_revalidate - revalidate an ecryptfs dentry
31 * @dentry: The ecryptfs dentry
32 * @nd: The associated nameidata
33 *
34 * Called when the VFS needs to revalidate a dentry. This
35 * is called whenever a name lookup finds a dentry in the
36 * dcache. Most filesystems leave this as NULL, because all their
37 * dentries in the dcache are valid.
38 *
39 * Returns 1 if valid, 0 otherwise.
40 *
41 */
42static int ecryptfs_d_revalidate(struct dentry *dentry, struct nameidata *nd)
43{
44 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
45 struct vfsmount *lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
46 struct dentry *dentry_save;
47 struct vfsmount *vfsmount_save;
48 int rc = 1;
49
50 if (!lower_dentry->d_op || !lower_dentry->d_op->d_revalidate)
51 goto out;
52 dentry_save = nd->dentry;
53 vfsmount_save = nd->mnt;
54 nd->dentry = lower_dentry;
55 nd->mnt = lower_mnt;
56 rc = lower_dentry->d_op->d_revalidate(lower_dentry, nd);
57 nd->dentry = dentry_save;
58 nd->mnt = vfsmount_save;
59out:
60 return rc;
61}
62
63struct kmem_cache *ecryptfs_dentry_info_cache;
64
65/**
66 * ecryptfs_d_release
67 * @dentry: The ecryptfs dentry
68 *
69 * Called when a dentry is really deallocated.
70 */
71static void ecryptfs_d_release(struct dentry *dentry)
72{
73 struct dentry *lower_dentry;
74
75 lower_dentry = ecryptfs_dentry_to_lower(dentry);
76 if (ecryptfs_dentry_to_private(dentry))
77 kmem_cache_free(ecryptfs_dentry_info_cache,
78 ecryptfs_dentry_to_private(dentry));
79 if (lower_dentry)
80 dput(lower_dentry);
81 return;
82}
83
84struct dentry_operations ecryptfs_dops = {
85 .d_revalidate = ecryptfs_d_revalidate,
86 .d_release = ecryptfs_d_release,
87};