Commit | Line | Data |
---|---|---|
8ec442ae DH |
1 | /* NFS FS-Cache index structure definition |
2 | * | |
3 | * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved. | |
4 | * Written by David Howells (dhowells@redhat.com) | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public Licence | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the Licence, or (at your option) any later version. | |
10 | */ | |
11 | ||
12 | #include <linux/init.h> | |
13 | #include <linux/kernel.h> | |
14 | #include <linux/sched.h> | |
15 | #include <linux/mm.h> | |
16 | #include <linux/nfs_fs.h> | |
17 | #include <linux/nfs_fs_sb.h> | |
18 | #include <linux/in6.h> | |
1eb5d98f | 19 | #include <linux/iversion.h> |
8ec442ae DH |
20 | |
21 | #include "internal.h" | |
22 | #include "fscache.h" | |
23 | ||
24 | #define NFSDBG_FACILITY NFSDBG_FSCACHE | |
25 | ||
26 | /* | |
27 | * Define the NFS filesystem for FS-Cache. Upon registration FS-Cache sticks | |
28 | * the cookie for the top-level index object for NFS into here. The top-level | |
29 | * index can than have other cache objects inserted into it. | |
30 | */ | |
31 | struct fscache_netfs nfs_fscache_netfs = { | |
32 | .name = "nfs", | |
33 | .version = 0, | |
34 | }; | |
35 | ||
36 | /* | |
37 | * Register NFS for caching | |
38 | */ | |
39 | int nfs_fscache_register(void) | |
40 | { | |
41 | return fscache_register_netfs(&nfs_fscache_netfs); | |
42 | } | |
43 | ||
44 | /* | |
45 | * Unregister NFS for caching | |
46 | */ | |
47 | void nfs_fscache_unregister(void) | |
48 | { | |
49 | fscache_unregister_netfs(&nfs_fscache_netfs); | |
50 | } | |
14727281 | 51 | |
14727281 DH |
52 | /* |
53 | * Define the server object for FS-Cache. This is used to describe a server | |
54 | * object to fscache_acquire_cookie(). It is keyed by the NFS protocol and | |
55 | * server address parameters. | |
56 | */ | |
57 | const struct fscache_cookie_def nfs_fscache_server_index_def = { | |
58 | .name = "NFS.server", | |
59 | .type = FSCACHE_COOKIE_TYPE_INDEX, | |
14727281 | 60 | }; |
08734048 | 61 | |
08734048 DH |
62 | /* |
63 | * Define the superblock object for FS-Cache. This is used to describe a | |
64 | * superblock object to fscache_acquire_cookie(). It is keyed by all the NFS | |
65 | * parameters that might cause a separate superblock. | |
66 | */ | |
67 | const struct fscache_cookie_def nfs_fscache_super_index_def = { | |
68 | .name = "NFS.super", | |
69 | .type = FSCACHE_COOKIE_TYPE_INDEX, | |
08734048 | 70 | }; |
10329a5d | 71 | |
10329a5d DH |
72 | /* |
73 | * Consult the netfs about the state of an object | |
74 | * - This function can be absent if the index carries no state data | |
75 | * - The netfs data from the cookie being used as the target is | |
76 | * presented, as is the auxiliary data | |
77 | */ | |
78 | static | |
79 | enum fscache_checkaux nfs_fscache_inode_check_aux(void *cookie_netfs_data, | |
80 | const void *data, | |
ee1235a9 DH |
81 | uint16_t datalen, |
82 | loff_t object_size) | |
10329a5d DH |
83 | { |
84 | struct nfs_fscache_inode_auxdata auxdata; | |
85 | struct nfs_inode *nfsi = cookie_netfs_data; | |
86 | ||
87 | if (datalen != sizeof(auxdata)) | |
88 | return FSCACHE_CHECKAUX_OBSOLETE; | |
89 | ||
90 | memset(&auxdata, 0, sizeof(auxdata)); | |
95582b00 DD |
91 | auxdata.mtime = timespec64_to_timespec(nfsi->vfs_inode.i_mtime); |
92 | auxdata.ctime = timespec64_to_timespec(nfsi->vfs_inode.i_ctime); | |
10329a5d DH |
93 | |
94 | if (NFS_SERVER(&nfsi->vfs_inode)->nfs_client->rpc_ops->version == 4) | |
1eb5d98f | 95 | auxdata.change_attr = inode_peek_iversion_raw(&nfsi->vfs_inode); |
10329a5d DH |
96 | |
97 | if (memcmp(data, &auxdata, datalen) != 0) | |
98 | return FSCACHE_CHECKAUX_OBSOLETE; | |
99 | ||
100 | return FSCACHE_CHECKAUX_OKAY; | |
101 | } | |
102 | ||
1fcdf534 DH |
103 | /* |
104 | * Get an extra reference on a read context. | |
105 | * - This function can be absent if the completion function doesn't require a | |
106 | * context. | |
107 | * - The read context is passed back to NFS in the event that a data read on the | |
108 | * cache fails with EIO - in which case the server must be contacted to | |
109 | * retrieve the data, which requires the read context for security. | |
110 | */ | |
111 | static void nfs_fh_get_context(void *cookie_netfs_data, void *context) | |
112 | { | |
113 | get_nfs_open_context(context); | |
114 | } | |
115 | ||
116 | /* | |
117 | * Release an extra reference on a read context. | |
118 | * - This function can be absent if the completion function doesn't require a | |
119 | * context. | |
120 | */ | |
121 | static void nfs_fh_put_context(void *cookie_netfs_data, void *context) | |
122 | { | |
123 | if (context) | |
124 | put_nfs_open_context(context); | |
125 | } | |
126 | ||
10329a5d DH |
127 | /* |
128 | * Define the inode object for FS-Cache. This is used to describe an inode | |
129 | * object to fscache_acquire_cookie(). It is keyed by the NFS file handle for | |
130 | * an inode. | |
131 | * | |
132 | * Coherency is managed by comparing the copies of i_size, i_mtime and i_ctime | |
133 | * held in the cache auxiliary data for the data storage object with those in | |
134 | * the inode struct in memory. | |
135 | */ | |
136 | const struct fscache_cookie_def nfs_fscache_inode_object_def = { | |
137 | .name = "NFS.fh", | |
138 | .type = FSCACHE_COOKIE_TYPE_DATAFILE, | |
10329a5d | 139 | .check_aux = nfs_fscache_inode_check_aux, |
1fcdf534 DH |
140 | .get_context = nfs_fh_get_context, |
141 | .put_context = nfs_fh_put_context, | |
10329a5d | 142 | }; |