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 extern struct fscache_netfs cifs_fscache_netfs;
  31 extern const struct fscache_cookie_def cifs_fscache_server_index_def;
  32 extern const struct fscache_cookie_def cifs_fscache_super_index_def;
  33 extern const struct fscache_cookie_def cifs_fscache_inode_object_def;
  34
  35 extern int cifs_fscache_register(void);
  36 extern void cifs_fscache_unregister(void);
  37
  38 /*
  39  * fscache.c
  40  */
  41 extern void cifs_fscache_get_client_cookie(struct TCP_Server_Info *);
  42 extern void cifs_fscache_release_client_cookie(struct TCP_Server_Info *);
  43 extern void cifs_fscache_get_super_cookie(struct cifsTconInfo *);
  44 extern void cifs_fscache_release_super_cookie(struct cifsTconInfo *);
  45
  46 extern void cifs_fscache_release_inode_cookie(struct inode *);
  47 extern void cifs_fscache_set_inode_cookie(struct inode *, struct file *);
  48 extern void cifs_fscache_reset_inode_cookie(struct inode *);
  49
  50 extern void __cifs_fscache_invalidate_page(struct page *, struct inode *);
  51 extern int cifs_fscache_release_page(struct page *page, gfp_t gfp);
  52 extern int __cifs_readpage_from_fscache(struct inode *, struct page *);
  53 extern int __cifs_readpages_from_fscache(struct inode *,
  54                                          struct address_space *,
  55                                          struct list_head *,
  56                                          unsigned *);
  57
  58 extern void __cifs_readpage_to_fscache(struct inode *, struct page *);
  59
  60 static inline void cifs_fscache_invalidate_page(struct page *page,
  61                                                struct inode *inode)
  62 {
  63         if (PageFsCache(page))
  64                 __cifs_fscache_invalidate_page(page, inode);
  65 }
  66
  67 static inline int cifs_readpage_from_fscache(struct inode *inode,
  68                                              struct page *page)
  69 {
  70         if (CIFS_I(inode)->fscache)
  71                 return __cifs_readpage_from_fscache(inode, page);
  72
  73         return -ENOBUFS;
  74 }
  75
  76 static inline int cifs_readpages_from_fscache(struct inode *inode,
  77                                               struct address_space *mapping,
  78                                               struct list_head *pages,
  79                                               unsigned *nr_pages)
  80 {
  81         if (CIFS_I(inode)->fscache)
  82                 return __cifs_readpages_from_fscache(inode, mapping, pages,
  83                                                      nr_pages);
  84         return -ENOBUFS;
  85 }
  86
  87 static inline void cifs_readpage_to_fscache(struct inode *inode,
  88                                             struct page *page)
  89 {
  90         if (PageFsCache(page))
  91                 __cifs_readpage_to_fscache(inode, page);
  92 }
  93
  94 #else /* CONFIG_CIFS_FSCACHE */
  95 static inline int cifs_fscache_register(void) { return 0; }
  96 static inline void cifs_fscache_unregister(void) {}
  97
  98 static inline void
  99 cifs_fscache_get_client_cookie(struct TCP_Server_Info *server) {}
 100 static inline void
 101 cifs_fscache_release_client_cookie(struct TCP_Server_Info *server) {}
 102 static inline void cifs_fscache_get_super_cookie(struct cifsTconInfo *tcon) {}
 103 static inline void
 104 cifs_fscache_release_super_cookie(struct cifsTconInfo *tcon) {}
 105
 106 static inline void cifs_fscache_release_inode_cookie(struct inode *inode) {}
 107 static inline void cifs_fscache_set_inode_cookie(struct inode *inode,
 108                                                  struct file *filp) {}
 109 static inline void cifs_fscache_reset_inode_cookie(struct inode *inode) {}
 110 static inline int cifs_fscache_release_page(struct page *page, gfp_t gfp)
 111 {
 112         return 1; /* May release page */
 113 }
 114
 115 static inline void cifs_fscache_invalidate_page(struct page *page,
 116                         struct inode *inode) {}
 117 static inline int
 118 cifs_readpage_from_fscache(struct inode *inode, struct page *page)
 119 {
 120         return -ENOBUFS;
 121 }
 122
 123 static inline int cifs_readpages_from_fscache(struct inode *inode,
 124                                               struct address_space *mapping,
 125                                               struct list_head *pages,
 126                                               unsigned *nr_pages)
 127 {
 128         return -ENOBUFS;
 129 }
 130
 131 static inline void cifs_readpage_to_fscache(struct inode *inode,
 132                         struct page *page) {}
 133
 134 #endif /* CONFIG_CIFS_FSCACHE */
 135
 136 #endif /* _CIFS_FSCACHE_H */