vfs: push dentry_unhash on rmdir into file systems
[linux-2.6.git] / 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
28 extern struct fscache_netfs v9fs_cache_netfs;
29 extern const struct fscache_cookie_def v9fs_cache_session_index_def;
30 extern const struct fscache_cookie_def v9fs_cache_inode_index_def;
31
32 extern void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses);
33 extern void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses);
34
35 extern void v9fs_cache_inode_get_cookie(struct inode *inode);
36 extern void v9fs_cache_inode_put_cookie(struct inode *inode);
37 extern void v9fs_cache_inode_flush_cookie(struct inode *inode);
38 extern void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp);
39 extern void v9fs_cache_inode_reset_cookie(struct inode *inode);
40
41 extern int __v9fs_cache_register(void);
42 extern void __v9fs_cache_unregister(void);
43
44 extern int __v9fs_fscache_release_page(struct page *page, gfp_t gfp);
45 extern void __v9fs_fscache_invalidate_page(struct page *page);
46 extern int __v9fs_readpage_from_fscache(struct inode *inode,
47                                         struct page *page);
48 extern int __v9fs_readpages_from_fscache(struct inode *inode,
49                                          struct address_space *mapping,
50                                          struct list_head *pages,
51                                          unsigned *nr_pages);
52 extern void __v9fs_readpage_to_fscache(struct inode *inode, struct page *page);
53 extern void __v9fs_fscache_wait_on_page_write(struct inode *inode,
54                                               struct page *page);
55
56 static inline int v9fs_fscache_release_page(struct page *page,
57                                             gfp_t gfp)
58 {
59         return __v9fs_fscache_release_page(page, gfp);
60 }
61
62 static inline void v9fs_fscache_invalidate_page(struct page *page)
63 {
64         __v9fs_fscache_invalidate_page(page);
65 }
66
67 static inline int v9fs_readpage_from_fscache(struct inode *inode,
68                                              struct page *page)
69 {
70         return __v9fs_readpage_from_fscache(inode, page);
71 }
72
73 static 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
82 static 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
89 static 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
96 static inline void v9fs_fscache_set_key(struct inode *inode,
97                                         struct p9_qid *qid)
98 {
99         struct v9fs_inode *v9inode = V9FS_I(inode);
100         spin_lock(&v9inode->fscache_lock);
101         v9inode->fscache_key = qid;
102         spin_unlock(&v9inode->fscache_lock);
103 }
104
105 static inline void v9fs_fscache_wait_on_page_write(struct inode *inode,
106                                                    struct page *page)
107 {
108         return __v9fs_fscache_wait_on_page_write(inode, page);
109 }
110
111 #else /* CONFIG_9P_FSCACHE */
112
113 static inline int v9fs_fscache_release_page(struct page *page,
114                                             gfp_t gfp) {
115         return 1;
116 }
117
118 static inline void v9fs_fscache_invalidate_page(struct page *page) {}
119
120 static inline int v9fs_readpage_from_fscache(struct inode *inode,
121                                              struct page *page)
122 {
123         return -ENOBUFS;
124 }
125
126 static inline int v9fs_readpages_from_fscache(struct inode *inode,
127                                               struct address_space *mapping,
128                                               struct list_head *pages,
129                                               unsigned *nr_pages)
130 {
131         return -ENOBUFS;
132 }
133
134 static inline void v9fs_readpage_to_fscache(struct inode *inode,
135                                             struct page *page)
136 {}
137
138 static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
139 {}
140
141 static inline void v9fs_fscache_wait_on_page_write(struct inode *inode,
142                                                    struct page *page)
143 {
144         return;
145 }
146
147 #endif /* CONFIG_9P_FSCACHE */
148 #endif /* _9P_CACHE_H */