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#define _9P_CACHE_H
  25#ifdef CONFIG_9P_FSCACHE
  26#include <linux/fscache.h>
  27#include <linux/spinlock.h>
  28
  29extern struct fscache_netfs v9fs_cache_netfs;
  30extern const struct fscache_cookie_def v9fs_cache_session_index_def;
  31extern const struct fscache_cookie_def v9fs_cache_inode_index_def;
  32
  33extern void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses);
  34extern void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses);
  35
  36extern void v9fs_cache_inode_get_cookie(struct inode *inode);
  37extern void v9fs_cache_inode_put_cookie(struct inode *inode);
  38extern void v9fs_cache_inode_flush_cookie(struct inode *inode);
  39extern void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp);
  40extern void v9fs_cache_inode_reset_cookie(struct inode *inode);
  41
  42extern int __v9fs_cache_register(void);
  43extern void __v9fs_cache_unregister(void);
  44
  45extern int __v9fs_fscache_release_page(struct page *page, gfp_t gfp);
  46extern void __v9fs_fscache_invalidate_page(struct page *page);
  47extern int __v9fs_readpage_from_fscache(struct inode *inode,
  48                                        struct page *page);
  49extern int __v9fs_readpages_from_fscache(struct inode *inode,
  50                                         struct address_space *mapping,
  51                                         struct list_head *pages,
  52                                         unsigned *nr_pages);
  53extern void __v9fs_readpage_to_fscache(struct inode *inode, struct page *page);
  54extern void __v9fs_fscache_wait_on_page_write(struct inode *inode,
  55                                              struct page *page);
  56
  57static inline int v9fs_fscache_release_page(struct page *page,
  58                                            gfp_t gfp)
  59{
  60        return __v9fs_fscache_release_page(page, gfp);
  61}
  62
  63static inline void v9fs_fscache_invalidate_page(struct page *page)
  64{
  65        __v9fs_fscache_invalidate_page(page);
  66}
  67
  68static inline int v9fs_readpage_from_fscache(struct inode *inode,
  69                                             struct page *page)
  70{
  71        return __v9fs_readpage_from_fscache(inode, page);
  72}
  73
  74static inline int v9fs_readpages_from_fscache(struct inode *inode,
  75                                              struct address_space *mapping,
  76                                              struct list_head *pages,
  77                                              unsigned *nr_pages)
  78{
  79        return __v9fs_readpages_from_fscache(inode, mapping, pages,
  80                                             nr_pages);
  81}
  82
  83static inline void v9fs_readpage_to_fscache(struct inode *inode,
  84                                            struct page *page)
  85{
  86        if (PageFsCache(page))
  87                __v9fs_readpage_to_fscache(inode, page);
  88}
  89
  90static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
  91{
  92        struct v9fs_inode *v9inode = V9FS_I(inode);
  93        fscache_uncache_page(v9inode->fscache, page);
  94        BUG_ON(PageFsCache(page));
  95}
  96
  97static inline void v9fs_fscache_wait_on_page_write(struct inode *inode,
  98                                                   struct page *page)
  99{
 100        return __v9fs_fscache_wait_on_page_write(inode, page);
 101}
 102
 103#else /* CONFIG_9P_FSCACHE */
 104
 105static inline void v9fs_cache_inode_get_cookie(struct inode *inode)
 106{
 107}
 108
 109static inline void v9fs_cache_inode_put_cookie(struct inode *inode)
 110{
 111}
 112
 113static inline void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *file)
 114{
 115}
 116
 117static inline int v9fs_fscache_release_page(struct page *page,
 118                                            gfp_t gfp) {
 119        return 1;
 120}
 121
 122static inline void v9fs_fscache_invalidate_page(struct page *page) {}
 123
 124static inline int v9fs_readpage_from_fscache(struct inode *inode,
 125                                             struct page *page)
 126{
 127        return -ENOBUFS;
 128}
 129
 130static inline int v9fs_readpages_from_fscache(struct inode *inode,
 131                                              struct address_space *mapping,
 132                                              struct list_head *pages,
 133                                              unsigned *nr_pages)
 134{
 135        return -ENOBUFS;
 136}
 137
 138static inline void v9fs_readpage_to_fscache(struct inode *inode,
 139                                            struct page *page)
 140{}
 141
 142static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
 143{}
 144
 145static inline void v9fs_fscache_wait_on_page_write(struct inode *inode,
 146                                                   struct page *page)
 147{
 148        return;
 149}
 150
 151#endif /* CONFIG_9P_FSCACHE */
 152#endif /* _9P_CACHE_H */
 153