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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 */
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/nfs_fs.h>
12#include <linux/nfs_mount.h>
13#include <linux/nfs4_mount.h>
14#include <linux/fscache.h>
15
16#ifdef CONFIG_NFS_FSCACHE
17
18/*
19 * set of NFS FS-Cache objects that form a superblock key
20 */
21struct nfs_fscache_key {
22 struct rb_node node;
23 struct nfs_client *nfs_client; /* the server */
24
25 /* the elements of the unique key - as used by nfs_compare_super() and
26 * nfs_compare_mount_options() to distinguish superblocks */
27 struct {
28 struct {
29 unsigned long s_flags; /* various flags
30 * (& NFS_MS_MASK) */
31 } super;
32
33 struct {
34 struct nfs_fsid fsid;
35 int flags;
36 unsigned int rsize; /* read size */
37 unsigned int wsize; /* write size */
38 unsigned int acregmin; /* attr cache timeouts */
39 unsigned int acregmax;
40 unsigned int acdirmin;
41 unsigned int acdirmax;
42 } nfs_server;
43
44 struct {
45 rpc_authflavor_t au_flavor;
46 } rpc_auth;
47
48 /* uniquifier - can be used if nfs_server.flags includes
49 * NFS_MOUNT_UNSHARED */
50 u8 uniq_len;
51 char uniquifier[0];
52 } key;
53};
54
55/*
56 * Definition of the auxiliary data attached to NFS inode storage objects
57 * within the cache.
58 *
59 * The contents of this struct are recorded in the on-disk local cache in the
60 * auxiliary data attached to the data storage object backing an inode. This
61 * permits coherency to be managed when a new inode binds to an already extant
62 * cache object.
63 */
64struct nfs_fscache_inode_auxdata {
65 s64 mtime_sec;
66 s64 mtime_nsec;
67 s64 ctime_sec;
68 s64 ctime_nsec;
69 u64 change_attr;
70};
71
72/*
73 * fscache-index.c
74 */
75extern struct fscache_netfs nfs_fscache_netfs;
76extern const struct fscache_cookie_def nfs_fscache_server_index_def;
77extern const struct fscache_cookie_def nfs_fscache_super_index_def;
78extern const struct fscache_cookie_def nfs_fscache_inode_object_def;
79
80extern int nfs_fscache_register(void);
81extern void nfs_fscache_unregister(void);
82
83/*
84 * fscache.c
85 */
86extern void nfs_fscache_get_client_cookie(struct nfs_client *);
87extern void nfs_fscache_release_client_cookie(struct nfs_client *);
88
89extern void nfs_fscache_get_super_cookie(struct super_block *, const char *, int);
90extern void nfs_fscache_release_super_cookie(struct super_block *);
91
92extern void nfs_fscache_init_inode(struct inode *);
93extern void nfs_fscache_clear_inode(struct inode *);
94extern void nfs_fscache_open_file(struct inode *, struct file *);
95
96extern void __nfs_fscache_invalidate_page(struct page *, struct inode *);
97extern int nfs_fscache_release_page(struct page *, gfp_t);
98
99extern int __nfs_readpage_from_fscache(struct nfs_open_context *,
100 struct inode *, struct page *);
101extern int __nfs_readpages_from_fscache(struct nfs_open_context *,
102 struct inode *, struct address_space *,
103 struct list_head *, unsigned *);
104extern void __nfs_readpage_to_fscache(struct inode *, struct page *, int);
105
106/*
107 * wait for a page to complete writing to the cache
108 */
109static inline void nfs_fscache_wait_on_page_write(struct nfs_inode *nfsi,
110 struct page *page)
111{
112 if (PageFsCache(page))
113 fscache_wait_on_page_write(nfsi->fscache, page);
114}
115
116/*
117 * release the caching state associated with a page if undergoing complete page
118 * invalidation
119 */
120static inline void nfs_fscache_invalidate_page(struct page *page,
121 struct inode *inode)
122{
123 if (PageFsCache(page))
124 __nfs_fscache_invalidate_page(page, inode);
125}
126
127/*
128 * Retrieve a page from an inode data storage object.
129 */
130static inline int nfs_readpage_from_fscache(struct nfs_open_context *ctx,
131 struct inode *inode,
132 struct page *page)
133{
134 if (NFS_I(inode)->fscache)
135 return __nfs_readpage_from_fscache(ctx, inode, page);
136 return -ENOBUFS;
137}
138
139/*
140 * Retrieve a set of pages from an inode data storage object.
141 */
142static inline int nfs_readpages_from_fscache(struct nfs_open_context *ctx,
143 struct inode *inode,
144 struct address_space *mapping,
145 struct list_head *pages,
146 unsigned *nr_pages)
147{
148 if (NFS_I(inode)->fscache)
149 return __nfs_readpages_from_fscache(ctx, inode, mapping, pages,
150 nr_pages);
151 return -ENOBUFS;
152}
153
154/*
155 * Store a page newly fetched from the server in an inode data storage object
156 * in the cache.
157 */
158static inline void nfs_readpage_to_fscache(struct inode *inode,
159 struct page *page,
160 int sync)
161{
162 if (PageFsCache(page))
163 __nfs_readpage_to_fscache(inode, page, sync);
164}
165
166/*
167 * Invalidate the contents of fscache for this inode. This will not sleep.
168 */
169static inline void nfs_fscache_invalidate(struct inode *inode)
170{
171 fscache_invalidate(NFS_I(inode)->fscache);
172}
173
174/*
175 * Wait for an object to finish being invalidated.
176 */
177static inline void nfs_fscache_wait_on_invalidate(struct inode *inode)
178{
179 fscache_wait_on_invalidate(NFS_I(inode)->fscache);
180}
181
182/*
183 * indicate the client caching state as readable text
184 */
185static inline const char *nfs_server_fscache_state(struct nfs_server *server)
186{
187 if (server->fscache)
188 return "yes";
189 return "no ";
190}
191
192#else /* CONFIG_NFS_FSCACHE */
193static inline int nfs_fscache_register(void) { return 0; }
194static inline void nfs_fscache_unregister(void) {}
195
196static inline void nfs_fscache_get_client_cookie(struct nfs_client *clp) {}
197static inline void nfs_fscache_release_client_cookie(struct nfs_client *clp) {}
198
199static inline void nfs_fscache_release_super_cookie(struct super_block *sb) {}
200
201static inline void nfs_fscache_init_inode(struct inode *inode) {}
202static inline void nfs_fscache_clear_inode(struct inode *inode) {}
203static inline void nfs_fscache_open_file(struct inode *inode,
204 struct file *filp) {}
205
206static inline int nfs_fscache_release_page(struct page *page, gfp_t gfp)
207{
208 return 1; /* True: may release page */
209}
210static inline void nfs_fscache_invalidate_page(struct page *page,
211 struct inode *inode) {}
212static inline void nfs_fscache_wait_on_page_write(struct nfs_inode *nfsi,
213 struct page *page) {}
214
215static inline int nfs_readpage_from_fscache(struct nfs_open_context *ctx,
216 struct inode *inode,
217 struct page *page)
218{
219 return -ENOBUFS;
220}
221static inline int nfs_readpages_from_fscache(struct nfs_open_context *ctx,
222 struct inode *inode,
223 struct address_space *mapping,
224 struct list_head *pages,
225 unsigned *nr_pages)
226{
227 return -ENOBUFS;
228}
229static inline void nfs_readpage_to_fscache(struct inode *inode,
230 struct page *page, int sync) {}
231
232
233static inline void nfs_fscache_invalidate(struct inode *inode) {}
234static inline void nfs_fscache_wait_on_invalidate(struct inode *inode) {}
235
236static inline const char *nfs_server_fscache_state(struct nfs_server *server)
237{
238 return "no ";
239}
240
241#endif /* CONFIG_NFS_FSCACHE */
242#endif /* _NFS_FSCACHE_H */