Loading...
1/* NFS filesystem cache interface definitions
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#ifndef _NFS_FSCACHE_H
13#define _NFS_FSCACHE_H
14
15#include <linux/nfs_fs.h>
16#include <linux/nfs_mount.h>
17#include <linux/nfs4_mount.h>
18#include <linux/fscache.h>
19
20#ifdef CONFIG_NFS_FSCACHE
21
22/*
23 * set of NFS FS-Cache objects that form a superblock key
24 */
25struct nfs_fscache_key {
26 struct rb_node node;
27 struct nfs_client *nfs_client; /* the server */
28
29 /* the elements of the unique key - as used by nfs_compare_super() and
30 * nfs_compare_mount_options() to distinguish superblocks */
31 struct {
32 struct {
33 unsigned long s_flags; /* various flags
34 * (& NFS_MS_MASK) */
35 } super;
36
37 struct {
38 struct nfs_fsid fsid;
39 int flags;
40 unsigned int rsize; /* read size */
41 unsigned int wsize; /* write size */
42 unsigned int acregmin; /* attr cache timeouts */
43 unsigned int acregmax;
44 unsigned int acdirmin;
45 unsigned int acdirmax;
46 } nfs_server;
47
48 struct {
49 rpc_authflavor_t au_flavor;
50 } rpc_auth;
51
52 /* uniquifier - can be used if nfs_server.flags includes
53 * NFS_MOUNT_UNSHARED */
54 u8 uniq_len;
55 char uniquifier[0];
56 } key;
57};
58
59/*
60 * fscache-index.c
61 */
62extern struct fscache_netfs nfs_fscache_netfs;
63extern const struct fscache_cookie_def nfs_fscache_server_index_def;
64extern const struct fscache_cookie_def nfs_fscache_super_index_def;
65extern const struct fscache_cookie_def nfs_fscache_inode_object_def;
66
67extern int nfs_fscache_register(void);
68extern void nfs_fscache_unregister(void);
69
70/*
71 * fscache.c
72 */
73extern void nfs_fscache_get_client_cookie(struct nfs_client *);
74extern void nfs_fscache_release_client_cookie(struct nfs_client *);
75
76extern void nfs_fscache_get_super_cookie(struct super_block *, const char *, int);
77extern void nfs_fscache_release_super_cookie(struct super_block *);
78
79extern void nfs_fscache_init_inode(struct inode *);
80extern void nfs_fscache_clear_inode(struct inode *);
81extern void nfs_fscache_open_file(struct inode *, struct file *);
82
83extern void __nfs_fscache_invalidate_page(struct page *, struct inode *);
84extern int nfs_fscache_release_page(struct page *, gfp_t);
85
86extern int __nfs_readpage_from_fscache(struct nfs_open_context *,
87 struct inode *, struct page *);
88extern int __nfs_readpages_from_fscache(struct nfs_open_context *,
89 struct inode *, struct address_space *,
90 struct list_head *, unsigned *);
91extern void __nfs_readpage_to_fscache(struct inode *, struct page *, int);
92
93/*
94 * wait for a page to complete writing to the cache
95 */
96static inline void nfs_fscache_wait_on_page_write(struct nfs_inode *nfsi,
97 struct page *page)
98{
99 if (PageFsCache(page))
100 fscache_wait_on_page_write(nfsi->fscache, page);
101}
102
103/*
104 * release the caching state associated with a page if undergoing complete page
105 * invalidation
106 */
107static inline void nfs_fscache_invalidate_page(struct page *page,
108 struct inode *inode)
109{
110 if (PageFsCache(page))
111 __nfs_fscache_invalidate_page(page, inode);
112}
113
114/*
115 * Retrieve a page from an inode data storage object.
116 */
117static inline int nfs_readpage_from_fscache(struct nfs_open_context *ctx,
118 struct inode *inode,
119 struct page *page)
120{
121 if (NFS_I(inode)->fscache)
122 return __nfs_readpage_from_fscache(ctx, inode, page);
123 return -ENOBUFS;
124}
125
126/*
127 * Retrieve a set of pages from an inode data storage object.
128 */
129static inline int nfs_readpages_from_fscache(struct nfs_open_context *ctx,
130 struct inode *inode,
131 struct address_space *mapping,
132 struct list_head *pages,
133 unsigned *nr_pages)
134{
135 if (NFS_I(inode)->fscache)
136 return __nfs_readpages_from_fscache(ctx, inode, mapping, pages,
137 nr_pages);
138 return -ENOBUFS;
139}
140
141/*
142 * Store a page newly fetched from the server in an inode data storage object
143 * in the cache.
144 */
145static inline void nfs_readpage_to_fscache(struct inode *inode,
146 struct page *page,
147 int sync)
148{
149 if (PageFsCache(page))
150 __nfs_readpage_to_fscache(inode, page, sync);
151}
152
153/*
154 * Invalidate the contents of fscache for this inode. This will not sleep.
155 */
156static inline void nfs_fscache_invalidate(struct inode *inode)
157{
158 fscache_invalidate(NFS_I(inode)->fscache);
159}
160
161/*
162 * Wait for an object to finish being invalidated.
163 */
164static inline void nfs_fscache_wait_on_invalidate(struct inode *inode)
165{
166 fscache_wait_on_invalidate(NFS_I(inode)->fscache);
167}
168
169/*
170 * indicate the client caching state as readable text
171 */
172static inline const char *nfs_server_fscache_state(struct nfs_server *server)
173{
174 if (server->fscache && (server->options & NFS_OPTION_FSCACHE))
175 return "yes";
176 return "no ";
177}
178
179#else /* CONFIG_NFS_FSCACHE */
180static inline int nfs_fscache_register(void) { return 0; }
181static inline void nfs_fscache_unregister(void) {}
182
183static inline void nfs_fscache_get_client_cookie(struct nfs_client *clp) {}
184static inline void nfs_fscache_release_client_cookie(struct nfs_client *clp) {}
185
186static inline void nfs_fscache_release_super_cookie(struct super_block *sb) {}
187
188static inline void nfs_fscache_init_inode(struct inode *inode) {}
189static inline void nfs_fscache_clear_inode(struct inode *inode) {}
190static inline void nfs_fscache_open_file(struct inode *inode,
191 struct file *filp) {}
192
193static inline int nfs_fscache_release_page(struct page *page, gfp_t gfp)
194{
195 return 1; /* True: may release page */
196}
197static inline void nfs_fscache_invalidate_page(struct page *page,
198 struct inode *inode) {}
199static inline void nfs_fscache_wait_on_page_write(struct nfs_inode *nfsi,
200 struct page *page) {}
201
202static inline int nfs_readpage_from_fscache(struct nfs_open_context *ctx,
203 struct inode *inode,
204 struct page *page)
205{
206 return -ENOBUFS;
207}
208static inline int nfs_readpages_from_fscache(struct nfs_open_context *ctx,
209 struct inode *inode,
210 struct address_space *mapping,
211 struct list_head *pages,
212 unsigned *nr_pages)
213{
214 return -ENOBUFS;
215}
216static inline void nfs_readpage_to_fscache(struct inode *inode,
217 struct page *page, int sync) {}
218
219
220static inline void nfs_fscache_invalidate(struct inode *inode) {}
221static inline void nfs_fscache_wait_on_invalidate(struct inode *inode) {}
222
223static inline const char *nfs_server_fscache_state(struct nfs_server *server)
224{
225 return "no ";
226}
227
228#endif /* CONFIG_NFS_FSCACHE */
229#endif /* _NFS_FSCACHE_H */
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/* NFS filesystem cache interface definitions
3 *
4 * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8#ifndef _NFS_FSCACHE_H
9#define _NFS_FSCACHE_H
10
11#include <linux/swap.h>
12#include <linux/nfs_fs.h>
13#include <linux/nfs_mount.h>
14#include <linux/nfs4_mount.h>
15#include <linux/fscache.h>
16#include <linux/iversion.h>
17
18#ifdef CONFIG_NFS_FSCACHE
19
20/*
21 * Definition of the auxiliary data attached to NFS inode storage objects
22 * within the cache.
23 *
24 * The contents of this struct are recorded in the on-disk local cache in the
25 * auxiliary data attached to the data storage object backing an inode. This
26 * permits coherency to be managed when a new inode binds to an already extant
27 * cache object.
28 */
29struct nfs_fscache_inode_auxdata {
30 s64 mtime_sec;
31 s64 mtime_nsec;
32 s64 ctime_sec;
33 s64 ctime_nsec;
34 u64 change_attr;
35};
36
37/*
38 * fscache.c
39 */
40extern int nfs_fscache_get_super_cookie(struct super_block *, const char *, int);
41extern void nfs_fscache_release_super_cookie(struct super_block *);
42
43extern void nfs_fscache_init_inode(struct inode *);
44extern void nfs_fscache_clear_inode(struct inode *);
45extern void nfs_fscache_open_file(struct inode *, struct file *);
46extern void nfs_fscache_release_file(struct inode *, struct file *);
47
48extern int __nfs_fscache_read_page(struct inode *, struct page *);
49extern void __nfs_fscache_write_page(struct inode *, struct page *);
50
51static inline bool nfs_fscache_release_folio(struct folio *folio, gfp_t gfp)
52{
53 if (folio_test_fscache(folio)) {
54 if (current_is_kswapd() || !(gfp & __GFP_FS))
55 return false;
56 folio_wait_fscache(folio);
57 fscache_note_page_release(nfs_i_fscache(folio->mapping->host));
58 nfs_inc_fscache_stats(folio->mapping->host,
59 NFSIOS_FSCACHE_PAGES_UNCACHED);
60 }
61 return true;
62}
63
64/*
65 * Retrieve a page from an inode data storage object.
66 */
67static inline int nfs_fscache_read_page(struct inode *inode, struct page *page)
68{
69 if (nfs_i_fscache(inode))
70 return __nfs_fscache_read_page(inode, page);
71 return -ENOBUFS;
72}
73
74/*
75 * Store a page newly fetched from the server in an inode data storage object
76 * in the cache.
77 */
78static inline void nfs_fscache_write_page(struct inode *inode,
79 struct page *page)
80{
81 if (nfs_i_fscache(inode))
82 __nfs_fscache_write_page(inode, page);
83}
84
85static inline void nfs_fscache_update_auxdata(struct nfs_fscache_inode_auxdata *auxdata,
86 struct inode *inode)
87{
88 memset(auxdata, 0, sizeof(*auxdata));
89 auxdata->mtime_sec = inode->i_mtime.tv_sec;
90 auxdata->mtime_nsec = inode->i_mtime.tv_nsec;
91 auxdata->ctime_sec = inode->i_ctime.tv_sec;
92 auxdata->ctime_nsec = inode->i_ctime.tv_nsec;
93
94 if (NFS_SERVER(inode)->nfs_client->rpc_ops->version == 4)
95 auxdata->change_attr = inode_peek_iversion_raw(inode);
96}
97
98/*
99 * Invalidate the contents of fscache for this inode. This will not sleep.
100 */
101static inline void nfs_fscache_invalidate(struct inode *inode, int flags)
102{
103 struct nfs_fscache_inode_auxdata auxdata;
104 struct nfs_inode *nfsi = NFS_I(inode);
105
106 if (nfsi->fscache) {
107 nfs_fscache_update_auxdata(&auxdata, inode);
108 fscache_invalidate(nfsi->fscache, &auxdata,
109 i_size_read(inode), flags);
110 }
111}
112
113/*
114 * indicate the client caching state as readable text
115 */
116static inline const char *nfs_server_fscache_state(struct nfs_server *server)
117{
118 if (server->fscache)
119 return "yes";
120 return "no ";
121}
122
123#else /* CONFIG_NFS_FSCACHE */
124static inline void nfs_fscache_release_super_cookie(struct super_block *sb) {}
125
126static inline void nfs_fscache_init_inode(struct inode *inode) {}
127static inline void nfs_fscache_clear_inode(struct inode *inode) {}
128static inline void nfs_fscache_open_file(struct inode *inode,
129 struct file *filp) {}
130static inline void nfs_fscache_release_file(struct inode *inode, struct file *file) {}
131
132static inline bool nfs_fscache_release_folio(struct folio *folio, gfp_t gfp)
133{
134 return true; /* may release folio */
135}
136static inline int nfs_fscache_read_page(struct inode *inode, struct page *page)
137{
138 return -ENOBUFS;
139}
140static inline void nfs_fscache_write_page(struct inode *inode, struct page *page) {}
141static inline void nfs_fscache_invalidate(struct inode *inode, int flags) {}
142
143static inline const char *nfs_server_fscache_state(struct nfs_server *server)
144{
145 return "no ";
146}
147
148#endif /* CONFIG_NFS_FSCACHE */
149#endif /* _NFS_FSCACHE_H */