LXR linux/fs/9p/cache.h

   1/*
   2 * V9FS cache definitions.
   3 *
   4 *  Copyright (C) 2009 by Abhishek Kulkarni <adkulkar@umail.iu.edu>
   5 *
   6 *  This program is free software; you can redistribute it and/or modify
   7 *  it under the terms of the GNU General Public License version 2
   8 *  as published by the Free Software Foundation.
   9 *
  10 *  This program is distributed in the hope that it will be useful,
  11 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 *  GNU General Public License for more details.
  14 *
  15 *  You should have received a copy of the GNU General Public License
  16 *  along with this program; if not, write to:
  17 *  Free Software Foundation
  18 *  51 Franklin Street, Fifth Floor
  19 *  Boston, MA  02111-1301  USA
  20 *
  21 */
  22
  23#ifndef _9P_CACHE_H
  24#ifdef CONFIG_9P_FSCACHE
  25#include <linux/fscache.h>
  26#include <linux/spinlock.h>
  27
  28extern struct fscache_netfs v9fs_cache_netfs;
  29extern const struct fscache_cookie_def v9fs_cache_session_index_def;
  30extern const struct fscache_cookie_def v9fs_cache_inode_index_def;
  31
  32extern void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses);
  33extern void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses);
  34
  35extern void v9fs_cache_inode_get_cookie(struct inode *inode);
  36extern void v9fs_cache_inode_put_cookie(struct inode *inode);
  37extern void v9fs_cache_inode_flush_cookie(struct inode *inode);
  38extern void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp);
  39extern void v9fs_cache_inode_reset_cookie(struct inode *inode);
  40
  41extern int __v9fs_cache_register(void);
  42extern void __v9fs_cache_unregister(void);
  43
  44extern int __v9fs_fscache_release_page(struct page *page, gfp_t gfp);
  45extern void __v9fs_fscache_invalidate_page(struct page *page);
  46extern int __v9fs_readpage_from_fscache(struct inode *inode,
  47                                        struct page *page);
  48extern int __v9fs_readpages_from_fscache(struct inode *inode,
  49                                         struct address_space *mapping,
  50                                         struct list_head *pages,
  51                                         unsigned *nr_pages);
  52extern void __v9fs_readpage_to_fscache(struct inode *inode, struct page *page);
  53extern void __v9fs_fscache_wait_on_page_write(struct inode *inode,
  54                                              struct page *page);
  55
  56static inline int v9fs_fscache_release_page(struct page *page,
  57                                            gfp_t gfp)
  58{
  59        return __v9fs_fscache_release_page(page, gfp);
  60}
  61
  62static inline void v9fs_fscache_invalidate_page(struct page *page)
  63{
  64        __v9fs_fscache_invalidate_page(page);
  65}
  66
  67static inline int v9fs_readpage_from_fscache(struct inode *inode,
  68                                             struct page *page)
  69{
  70        return __v9fs_readpage_from_fscache(inode, page);
  71}
  72
  73static inline int v9fs_readpages_from_fscache(struct inode *inode,
  74                                              struct address_space *mapping,
  75                                              struct list_head *pages,
  76                                              unsigned *nr_pages)
  77{
  78        return __v9fs_readpages_from_fscache(inode, mapping, pages,
  79                                             nr_pages);
  80}
  81
  82static inline void v9fs_readpage_to_fscache(struct inode *inode,
  83                                            struct page *page)
  84{
  85        if (PageFsCache(page))
  86                __v9fs_readpage_to_fscache(inode, page);
  87}
  88
  89static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
  90{
  91        struct v9fs_inode *v9inode = V9FS_I(inode);
  92        fscache_uncache_page(v9inode->fscache, page);
  93        BUG_ON(PageFsCache(page));
  94}
  95
  96static inline void v9fs_fscache_wait_on_page_write(struct inode *inode,
  97                                                   struct page *page)
  98{
  99        return __v9fs_fscache_wait_on_page_write(inode, page);
 100}
 101
 102#else /* CONFIG_9P_FSCACHE */
 103
 104static inline void v9fs_cache_inode_get_cookie(struct inode *inode)
 105{
 106}
 107
 108static inline void v9fs_cache_inode_put_cookie(struct inode *inode)
 109{
 110}
 111
 112static inline void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *file)
 113{
 114}
 115
 116static inline int v9fs_fscache_release_page(struct page *page,
 117                                            gfp_t gfp) {
 118        return 1;
 119}
 120
 121static inline void v9fs_fscache_invalidate_page(struct page *page) {}
 122
 123static inline int v9fs_readpage_from_fscache(struct inode *inode,
 124                                             struct page *page)
 125{
 126        return -ENOBUFS;
 127}
 128
 129static inline int v9fs_readpages_from_fscache(struct inode *inode,
 130                                              struct address_space *mapping,
 131                                              struct list_head *pages,
 132                                              unsigned *nr_pages)
 133{
 134        return -ENOBUFS;
 135}
 136
 137static inline void v9fs_readpage_to_fscache(struct inode *inode,
 138                                            struct page *page)
 139{}
 140
 141static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
 142{}
 143
 144static inline void v9fs_fscache_wait_on_page_write(struct inode *inode,
 145                                                   struct page *page)
 146{
 147        return;
 148}
 149
 150#endif /* CONFIG_9P_FSCACHE */
 151#endif /* _9P_CACHE_H */
 152