xref: /linux/fs/ceph/cache.h (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
1 /*
2  * Ceph cache definitions.
3  *
4  *  Copyright (C) 2013 by Adfin Solutions, Inc. All Rights Reserved.
5  *  Written by Milosz Tanski (milosz@adfin.com)
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License version 2
9  *  as published by the Free Software Foundation.
10  *
11  *  This program is distributed in the hope that it will be useful,
12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *  GNU General Public License for more details.
15  *
16  *  You should have received a copy of the GNU General Public License
17  *  along with this program; if not, write to:
18  *  Free Software Foundation
19  *  51 Franklin Street, Fifth Floor
20  *  Boston, MA  02111-1301  USA
21  *
22  */
23 
24 #ifndef _CEPH_CACHE_H
25 #define _CEPH_CACHE_H
26 
27 #ifdef CONFIG_CEPH_FSCACHE
28 
29 extern struct fscache_netfs ceph_cache_netfs;
30 
31 int ceph_fscache_register(void);
32 void ceph_fscache_unregister(void);
33 
34 int ceph_fscache_register_fs(struct ceph_fs_client* fsc);
35 void ceph_fscache_unregister_fs(struct ceph_fs_client* fsc);
36 
37 void ceph_fscache_register_inode_cookie(struct inode *inode);
38 void ceph_fscache_unregister_inode_cookie(struct ceph_inode_info* ci);
39 void ceph_fscache_file_set_cookie(struct inode *inode, struct file *filp);
40 void ceph_fscache_revalidate_cookie(struct ceph_inode_info *ci);
41 
42 int ceph_readpage_from_fscache(struct inode *inode, struct page *page);
43 int ceph_readpages_from_fscache(struct inode *inode,
44 				struct address_space *mapping,
45 				struct list_head *pages,
46 				unsigned *nr_pages);
47 void ceph_readpage_to_fscache(struct inode *inode, struct page *page);
48 void ceph_invalidate_fscache_page(struct inode* inode, struct page *page);
49 
50 static inline void ceph_fscache_inode_init(struct ceph_inode_info *ci)
51 {
52 	ci->fscache = NULL;
53 	ci->i_fscache_gen = 0;
54 }
55 
56 static inline void ceph_fscache_invalidate(struct inode *inode)
57 {
58 	fscache_invalidate(ceph_inode(inode)->fscache);
59 }
60 
61 static inline void ceph_fscache_uncache_page(struct inode *inode,
62 					     struct page *page)
63 {
64 	struct ceph_inode_info *ci = ceph_inode(inode);
65 	return fscache_uncache_page(ci->fscache, page);
66 }
67 
68 static inline int ceph_release_fscache_page(struct page *page, gfp_t gfp)
69 {
70 	struct inode* inode = page->mapping->host;
71 	struct ceph_inode_info *ci = ceph_inode(inode);
72 	return fscache_maybe_release_page(ci->fscache, page, gfp);
73 }
74 
75 static inline void ceph_fscache_readpage_cancel(struct inode *inode,
76 						struct page *page)
77 {
78 	struct ceph_inode_info *ci = ceph_inode(inode);
79 	if (fscache_cookie_valid(ci->fscache) && PageFsCache(page))
80 		__fscache_uncache_page(ci->fscache, page);
81 }
82 
83 static inline void ceph_fscache_readpages_cancel(struct inode *inode,
84 						 struct list_head *pages)
85 {
86 	struct ceph_inode_info *ci = ceph_inode(inode);
87 	return fscache_readpages_cancel(ci->fscache, pages);
88 }
89 
90 static inline void ceph_disable_fscache_readpage(struct ceph_inode_info *ci)
91 {
92 	ci->i_fscache_gen = ci->i_rdcache_gen - 1;
93 }
94 
95 #else
96 
97 static inline int ceph_fscache_register(void)
98 {
99 	return 0;
100 }
101 
102 static inline void ceph_fscache_unregister(void)
103 {
104 }
105 
106 static inline int ceph_fscache_register_fs(struct ceph_fs_client* fsc)
107 {
108 	return 0;
109 }
110 
111 static inline void ceph_fscache_unregister_fs(struct ceph_fs_client* fsc)
112 {
113 }
114 
115 static inline void ceph_fscache_inode_init(struct ceph_inode_info *ci)
116 {
117 }
118 
119 static inline void ceph_fscache_register_inode_cookie(struct inode *inode)
120 {
121 }
122 
123 static inline void ceph_fscache_unregister_inode_cookie(struct ceph_inode_info* ci)
124 {
125 }
126 
127 static inline void ceph_fscache_file_set_cookie(struct inode *inode,
128 						struct file *filp)
129 {
130 }
131 
132 static inline void ceph_fscache_revalidate_cookie(struct ceph_inode_info *ci)
133 {
134 }
135 
136 static inline void ceph_fscache_uncache_page(struct inode *inode,
137 					     struct page *pages)
138 {
139 }
140 
141 static inline int ceph_readpage_from_fscache(struct inode* inode,
142 					     struct page *page)
143 {
144 	return -ENOBUFS;
145 }
146 
147 static inline int ceph_readpages_from_fscache(struct inode *inode,
148 					      struct address_space *mapping,
149 					      struct list_head *pages,
150 					      unsigned *nr_pages)
151 {
152 	return -ENOBUFS;
153 }
154 
155 static inline void ceph_readpage_to_fscache(struct inode *inode,
156 					    struct page *page)
157 {
158 }
159 
160 static inline void ceph_fscache_invalidate(struct inode *inode)
161 {
162 }
163 
164 static inline void ceph_invalidate_fscache_page(struct inode *inode,
165 						struct page *page)
166 {
167 }
168 
169 static inline int ceph_release_fscache_page(struct page *page, gfp_t gfp)
170 {
171 	return 1;
172 }
173 
174 static inline void ceph_fscache_readpage_cancel(struct inode *inode,
175 						struct page *page)
176 {
177 }
178 
179 static inline void ceph_fscache_readpages_cancel(struct inode *inode,
180 						 struct list_head *pages)
181 {
182 }
183 
184 static inline void ceph_disable_fscache_readpage(struct ceph_inode_info *ci)
185 {
186 }
187 
188 #endif
189 
190 #endif
191