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 int v9fs_fscache_release_page(struct page *page,
 105                                            gfp_t gfp) {
 106        return 1;
 107}
 108
 109static inline void v9fs_fscache_invalidate_page(struct page *page) {}
 110
 111static inline int v9fs_readpage_from_fscache(struct inode *inode,
 112                                             struct page *page)
 113{
 114        return -ENOBUFS;
 115}
 116
 117static inline int v9fs_readpages_from_fscache(struct inode *inode,
 118                                              struct address_space *mapping,
 119                                              struct list_head *pages,
 120                                              unsigned *nr_pages)
 121{
 122        return -ENOBUFS;
 123}
 124
 125static inline void v9fs_readpage_to_fscache(struct inode *inode,
 126                                            struct page *page)
 127{}
 128
 129static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
 130{}
 131
 132static inline void v9fs_fscache_wait_on_page_write(struct inode *inode,
 133                                                   struct page *page)
 134{
 135        return;
 136}
 137
 138#endif /* CONFIG_9P_FSCACHE */
 139#endif /* _9P_CACHE_H */
 140