x86/amd-iommu: Add per IOMMU reference counting
[linux/fpc-iii.git] / fs / nfs / fscache.h
blobb9c572d0679f8ced0aead467778d56229de9a03b
1 /* NFS filesystem cache interface definitions
3 * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
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.
12 #ifndef _NFS_FSCACHE_H
13 #define _NFS_FSCACHE_H
15 #include <linux/nfs_fs.h>
16 #include <linux/nfs_mount.h>
17 #include <linux/nfs4_mount.h>
18 #include <linux/fscache.h>
20 #ifdef CONFIG_NFS_FSCACHE
23 * set of NFS FS-Cache objects that form a superblock key
25 struct nfs_fscache_key {
26 struct rb_node node;
27 struct nfs_client *nfs_client; /* the server */
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;
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;
48 struct {
49 rpc_authflavor_t au_flavor;
50 } rpc_auth;
52 /* uniquifier - can be used if nfs_server.flags includes
53 * NFS_MOUNT_UNSHARED */
54 u8 uniq_len;
55 char uniquifier[0];
56 } key;
60 * fscache-index.c
62 extern struct fscache_netfs nfs_fscache_netfs;
63 extern const struct fscache_cookie_def nfs_fscache_server_index_def;
64 extern const struct fscache_cookie_def nfs_fscache_super_index_def;
65 extern const struct fscache_cookie_def nfs_fscache_inode_object_def;
67 extern int nfs_fscache_register(void);
68 extern void nfs_fscache_unregister(void);
71 * fscache.c
73 extern void nfs_fscache_get_client_cookie(struct nfs_client *);
74 extern void nfs_fscache_release_client_cookie(struct nfs_client *);
76 extern void nfs_fscache_get_super_cookie(struct super_block *,
77 const char *,
78 struct nfs_clone_mount *);
79 extern void nfs_fscache_release_super_cookie(struct super_block *);
81 extern void nfs_fscache_init_inode_cookie(struct inode *);
82 extern void nfs_fscache_release_inode_cookie(struct inode *);
83 extern void nfs_fscache_zap_inode_cookie(struct inode *);
84 extern void nfs_fscache_set_inode_cookie(struct inode *, struct file *);
85 extern void nfs_fscache_reset_inode_cookie(struct inode *);
87 extern void __nfs_fscache_invalidate_page(struct page *, struct inode *);
88 extern int nfs_fscache_release_page(struct page *, gfp_t);
90 extern int __nfs_readpage_from_fscache(struct nfs_open_context *,
91 struct inode *, struct page *);
92 extern int __nfs_readpages_from_fscache(struct nfs_open_context *,
93 struct inode *, struct address_space *,
94 struct list_head *, unsigned *);
95 extern void __nfs_readpage_to_fscache(struct inode *, struct page *, int);
98 * wait for a page to complete writing to the cache
100 static inline void nfs_fscache_wait_on_page_write(struct nfs_inode *nfsi,
101 struct page *page)
103 if (PageFsCache(page))
104 fscache_wait_on_page_write(nfsi->fscache, page);
108 * release the caching state associated with a page if undergoing complete page
109 * invalidation
111 static inline void nfs_fscache_invalidate_page(struct page *page,
112 struct inode *inode)
114 if (PageFsCache(page))
115 __nfs_fscache_invalidate_page(page, inode);
119 * Retrieve a page from an inode data storage object.
121 static inline int nfs_readpage_from_fscache(struct nfs_open_context *ctx,
122 struct inode *inode,
123 struct page *page)
125 if (NFS_I(inode)->fscache)
126 return __nfs_readpage_from_fscache(ctx, inode, page);
127 return -ENOBUFS;
131 * Retrieve a set of pages from an inode data storage object.
133 static inline int nfs_readpages_from_fscache(struct nfs_open_context *ctx,
134 struct inode *inode,
135 struct address_space *mapping,
136 struct list_head *pages,
137 unsigned *nr_pages)
139 if (NFS_I(inode)->fscache)
140 return __nfs_readpages_from_fscache(ctx, inode, mapping, pages,
141 nr_pages);
142 return -ENOBUFS;
146 * Store a page newly fetched from the server in an inode data storage object
147 * in the cache.
149 static inline void nfs_readpage_to_fscache(struct inode *inode,
150 struct page *page,
151 int sync)
153 if (PageFsCache(page))
154 __nfs_readpage_to_fscache(inode, page, sync);
158 * indicate the client caching state as readable text
160 static inline const char *nfs_server_fscache_state(struct nfs_server *server)
162 if (server->fscache && (server->options & NFS_OPTION_FSCACHE))
163 return "yes";
164 return "no ";
168 #else /* CONFIG_NFS_FSCACHE */
169 static inline int nfs_fscache_register(void) { return 0; }
170 static inline void nfs_fscache_unregister(void) {}
172 static inline void nfs_fscache_get_client_cookie(struct nfs_client *clp) {}
173 static inline void nfs_fscache_release_client_cookie(struct nfs_client *clp) {}
175 static inline void nfs_fscache_get_super_cookie(
176 struct super_block *sb,
177 const char *uniq,
178 struct nfs_clone_mount *mntdata)
181 static inline void nfs_fscache_release_super_cookie(struct super_block *sb) {}
183 static inline void nfs_fscache_init_inode_cookie(struct inode *inode) {}
184 static inline void nfs_fscache_release_inode_cookie(struct inode *inode) {}
185 static inline void nfs_fscache_zap_inode_cookie(struct inode *inode) {}
186 static inline void nfs_fscache_set_inode_cookie(struct inode *inode,
187 struct file *filp) {}
188 static inline void nfs_fscache_reset_inode_cookie(struct inode *inode) {}
190 static inline int nfs_fscache_release_page(struct page *page, gfp_t gfp)
192 return 1; /* True: may release page */
194 static inline void nfs_fscache_invalidate_page(struct page *page,
195 struct inode *inode) {}
196 static inline void nfs_fscache_wait_on_page_write(struct nfs_inode *nfsi,
197 struct page *page) {}
199 static inline int nfs_readpage_from_fscache(struct nfs_open_context *ctx,
200 struct inode *inode,
201 struct page *page)
203 return -ENOBUFS;
205 static inline int nfs_readpages_from_fscache(struct nfs_open_context *ctx,
206 struct inode *inode,
207 struct address_space *mapping,
208 struct list_head *pages,
209 unsigned *nr_pages)
211 return -ENOBUFS;
213 static inline void nfs_readpage_to_fscache(struct inode *inode,
214 struct page *page, int sync) {}
216 static inline const char *nfs_server_fscache_state(struct nfs_server *server)
218 return "no ";
221 #endif /* CONFIG_NFS_FSCACHE */
222 #endif /* _NFS_FSCACHE_H */