fs/cifs/fscache.h

   1 /*
   2  *   fs/cifs/fscache.h - CIFS filesystem cache interface definitions
   3  *
   4  *   Copyright (c) 2010 Novell, Inc.
   5  *   Authors(s): Suresh Jayaraman (sjayaraman@suse.de>
   6  *
   7  *   This library is free software; you can redistribute it and/or modify
   8  *   it under the terms of the GNU Lesser General Public License as published
   9  *   by the Free Software Foundation; either version 2.1 of the License, or
  10  *   (at your option) any later version.
  11  *
  12  *   This library is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  15  *   the GNU Lesser General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU Lesser General Public License
  18  *   along with this library; if not, write to the Free Software
  19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  20  */
  21 #ifndef _CIFS_FSCACHE_H
  22 #define _CIFS_FSCACHE_H
  23
  24 #include <linux/fscache.h>
  25
  26 #include "cifsglob.h"
  27
  28 #ifdef CONFIG_CIFS_FSCACHE
  29
  30 /*
  31  * Auxiliary data attached to CIFS inode within the cache
  32  */
  33 struct cifs_fscache_inode_auxdata {
  34         u64 last_write_time_sec;
  35         u64 last_change_time_sec;
  36         u32 last_write_time_nsec;
  37         u32 last_change_time_nsec;
  38         u64 eof;
  39 };
  40
  41 /*
  42  * cache.c
  43  */
  44 extern struct fscache_netfs cifs_fscache_netfs;
  45 extern const struct fscache_cookie_def cifs_fscache_server_index_def;
  46 extern const struct fscache_cookie_def cifs_fscache_super_index_def;
  47 extern const struct fscache_cookie_def cifs_fscache_inode_object_def;
  48
  49 extern int cifs_fscache_register(void);
  50 extern void cifs_fscache_unregister(void);
  51 extern char *extract_sharename(const char *);
  52
  53 /*
  54  * fscache.c
  55  */
  56 extern void cifs_fscache_get_client_cookie(struct TCP_Server_Info *);
  57 extern void cifs_fscache_release_client_cookie(struct TCP_Server_Info *);
  58 extern void cifs_fscache_get_super_cookie(struct cifs_tcon *);
  59 extern void cifs_fscache_release_super_cookie(struct cifs_tcon *);
  60
  61 extern void cifs_fscache_release_inode_cookie(struct inode *);
  62 extern void cifs_fscache_set_inode_cookie(struct inode *, struct file *);
  63 extern void cifs_fscache_reset_inode_cookie(struct inode *);
  64
  65 extern void __cifs_fscache_invalidate_page(struct page *, struct inode *);
  66 extern int cifs_fscache_release_page(struct page *page, gfp_t gfp);
  67 extern int __cifs_readpage_from_fscache(struct inode *, struct page *);
  68 extern int __cifs_readpages_from_fscache(struct inode *,
  69                                          struct address_space *,
  70                                          struct list_head *,
  71                                          unsigned *);
  72 extern void __cifs_fscache_readpages_cancel(struct inode *, struct list_head *);
  73
  74 extern void __cifs_readpage_to_fscache(struct inode *, struct page *);
  75
  76 static inline void cifs_fscache_invalidate_page(struct page *page,
  77                                                struct inode *inode)
  78 {
  79         if (PageFsCache(page))
  80                 __cifs_fscache_invalidate_page(page, inode);
  81 }
  82
  83 static inline int cifs_readpage_from_fscache(struct inode *inode,
  84                                              struct page *page)
  85 {
  86         if (CIFS_I(inode)->fscache)
  87                 return __cifs_readpage_from_fscache(inode, page);
  88
  89         return -ENOBUFS;
  90 }
  91
  92 static inline int cifs_readpages_from_fscache(struct inode *inode,
  93                                               struct address_space *mapping,
  94                                               struct list_head *pages,
  95                                               unsigned *nr_pages)
  96 {
  97         if (CIFS_I(inode)->fscache)
  98                 return __cifs_readpages_from_fscache(inode, mapping, pages,
  99                                                      nr_pages);
 100         return -ENOBUFS;
 101 }
 102
 103 static inline void cifs_readpage_to_fscache(struct inode *inode,
 104                                             struct page *page)
 105 {
 106         if (PageFsCache(page))
 107                 __cifs_readpage_to_fscache(inode, page);
 108 }
 109
 110 static inline void cifs_fscache_readpages_cancel(struct inode *inode,
 111                                                  struct list_head *pages)
 112 {
 113         if (CIFS_I(inode)->fscache)
 114                 return __cifs_fscache_readpages_cancel(inode, pages);
 115 }
 116
 117 #else /* CONFIG_CIFS_FSCACHE */
 118 static inline int cifs_fscache_register(void) { return 0; }
 119 static inline void cifs_fscache_unregister(void) {}
 120
 121 static inline void
 122 cifs_fscache_get_client_cookie(struct TCP_Server_Info *server) {}
 123 static inline void
 124 cifs_fscache_release_client_cookie(struct TCP_Server_Info *server) {}
 125 static inline void cifs_fscache_get_super_cookie(struct cifs_tcon *tcon) {}
 126 static inline void
 127 cifs_fscache_release_super_cookie(struct cifs_tcon *tcon) {}
 128
 129 static inline void cifs_fscache_release_inode_cookie(struct inode *inode) {}
 130 static inline void cifs_fscache_set_inode_cookie(struct inode *inode,
 131                                                  struct file *filp) {}
 132 static inline void cifs_fscache_reset_inode_cookie(struct inode *inode) {}
 133 static inline int cifs_fscache_release_page(struct page *page, gfp_t gfp)
 134 {
 135         return 1; /* May release page */
 136 }
 137
 138 static inline void cifs_fscache_invalidate_page(struct page *page,
 139                         struct inode *inode) {}
 140 static inline int
 141 cifs_readpage_from_fscache(struct inode *inode, struct page *page)
 142 {
 143         return -ENOBUFS;
 144 }
 145
 146 static inline int cifs_readpages_from_fscache(struct inode *inode,
 147                                               struct address_space *mapping,
 148                                               struct list_head *pages,
 149                                               unsigned *nr_pages)
 150 {
 151         return -ENOBUFS;
 152 }
 153
 154 static inline void cifs_readpage_to_fscache(struct inode *inode,
 155                         struct page *page) {}
 156
 157 static inline void cifs_fscache_readpages_cancel(struct inode *inode,
 158                                                  struct list_head *pages)
 159 {
 160 }
 161
 162 #endif /* CONFIG_CIFS_FSCACHE */
 163
 164 #endif /* _CIFS_FSCACHE_H */