xref: /openbmc/linux/fs/9p/cache.h (revision 4beec1d7)
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 
29 extern struct fscache_netfs v9fs_cache_netfs;
30 extern const struct fscache_cookie_def v9fs_cache_session_index_def;
31 extern const struct fscache_cookie_def v9fs_cache_inode_index_def;
32 
33 extern void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses);
34 extern void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses);
35 
36 extern void v9fs_cache_inode_get_cookie(struct inode *inode);
37 extern void v9fs_cache_inode_put_cookie(struct inode *inode);
38 extern void v9fs_cache_inode_flush_cookie(struct inode *inode);
39 extern void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp);
40 extern void v9fs_cache_inode_reset_cookie(struct inode *inode);
41 
42 extern int __v9fs_cache_register(void);
43 extern void __v9fs_cache_unregister(void);
44 
45 extern int __v9fs_fscache_release_page(struct page *page, gfp_t gfp);
46 extern void __v9fs_fscache_invalidate_page(struct page *page);
47 extern int __v9fs_readpage_from_fscache(struct inode *inode,
48 					struct page *page);
49 extern int __v9fs_readpages_from_fscache(struct inode *inode,
50 					 struct address_space *mapping,
51 					 struct list_head *pages,
52 					 unsigned *nr_pages);
53 extern void __v9fs_readpage_to_fscache(struct inode *inode, struct page *page);
54 extern void __v9fs_fscache_wait_on_page_write(struct inode *inode,
55 					      struct page *page);
56 
57 static inline int v9fs_fscache_release_page(struct page *page,
58 					    gfp_t gfp)
59 {
60 	return __v9fs_fscache_release_page(page, gfp);
61 }
62 
63 static inline void v9fs_fscache_invalidate_page(struct page *page)
64 {
65 	__v9fs_fscache_invalidate_page(page);
66 }
67 
68 static inline int v9fs_readpage_from_fscache(struct inode *inode,
69 					     struct page *page)
70 {
71 	return __v9fs_readpage_from_fscache(inode, page);
72 }
73 
74 static 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 
83 static 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 
90 static 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 
97 static 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 
105 static inline void v9fs_cache_inode_get_cookie(struct inode *inode)
106 {
107 }
108 
109 static inline void v9fs_cache_inode_put_cookie(struct inode *inode)
110 {
111 }
112 
113 static inline void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *file)
114 {
115 }
116 
117 static inline int v9fs_fscache_release_page(struct page *page,
118 					    gfp_t gfp) {
119 	return 1;
120 }
121 
122 static inline void v9fs_fscache_invalidate_page(struct page *page) {}
123 
124 static inline int v9fs_readpage_from_fscache(struct inode *inode,
125 					     struct page *page)
126 {
127 	return -ENOBUFS;
128 }
129 
130 static 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 
138 static inline void v9fs_readpage_to_fscache(struct inode *inode,
139 					    struct page *page)
140 {}
141 
142 static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
143 {}
144 
145 static 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