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 */