1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* AFS caching stuff
3 *
4 * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8 #include <linux/sched.h>
9 #include "internal.h"
10
11 static enum fscache_checkaux afs_vnode_cache_check_aux(void *cookie_netfs_data,
12 const void *buffer,
13 uint16_t buflen,
14 loff_t object_size);
15
16 struct fscache_netfs afs_cache_netfs = {
17 .name = "afs",
18 .version = 2,
19 };
20
21 struct fscache_cookie_def afs_cell_cache_index_def = {
22 .name = "AFS.cell",
23 .type = FSCACHE_COOKIE_TYPE_INDEX,
24 };
25
26 struct fscache_cookie_def afs_volume_cache_index_def = {
27 .name = "AFS.volume",
28 .type = FSCACHE_COOKIE_TYPE_INDEX,
29 };
30
31 struct fscache_cookie_def afs_vnode_cache_index_def = {
32 .name = "AFS.vnode",
33 .type = FSCACHE_COOKIE_TYPE_DATAFILE,
34 .check_aux = afs_vnode_cache_check_aux,
35 };
36
37 /*
38 * check that the auxiliary data indicates that the entry is still valid
39 */
afs_vnode_cache_check_aux(void * cookie_netfs_data,const void * buffer,uint16_t buflen,loff_t object_size)40 static enum fscache_checkaux afs_vnode_cache_check_aux(void *cookie_netfs_data,
41 const void *buffer,
42 uint16_t buflen,
43 loff_t object_size)
44 {
45 struct afs_vnode *vnode = cookie_netfs_data;
46 struct afs_vnode_cache_aux aux;
47
48 _enter("{%llx,%x,%llx},%p,%u",
49 vnode->fid.vnode, vnode->fid.unique, vnode->status.data_version,
50 buffer, buflen);
51
52 memcpy(&aux, buffer, sizeof(aux));
53
54 /* check the size of the data is what we're expecting */
55 if (buflen != sizeof(aux)) {
56 _leave(" = OBSOLETE [len %hx != %zx]", buflen, sizeof(aux));
57 return FSCACHE_CHECKAUX_OBSOLETE;
58 }
59
60 if (vnode->status.data_version != aux.data_version) {
61 _leave(" = OBSOLETE [vers %llx != %llx]",
62 aux.data_version, vnode->status.data_version);
63 return FSCACHE_CHECKAUX_OBSOLETE;
64 }
65
66 _leave(" = SUCCESS");
67 return FSCACHE_CHECKAUX_OKAY;
68 }
69
