xref: /linux/fs/ceph/cache.h (revision c98be0c96db00e9b6b02d31e0fa7590c54cdaaac)
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_inode_init(struct ceph_inode_info *ci);
38 void ceph_fscache_register_inode_cookie(struct ceph_fs_client* fsc,
39 					struct ceph_inode_info* ci);
40 void ceph_fscache_unregister_inode_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 void ceph_queue_revalidate(struct inode *inode);
50 
51 static inline void ceph_fscache_invalidate(struct inode *inode)
52 {
53 	fscache_invalidate(ceph_inode(inode)->fscache);
54 }
55 
56 static inline void ceph_fscache_uncache_page(struct inode *inode,
57 					     struct page *page)
58 {
59 	struct ceph_inode_info *ci = ceph_inode(inode);
60 	return fscache_uncache_page(ci->fscache, page);
61 }
62 
63 static inline int ceph_release_fscache_page(struct page *page, gfp_t gfp)
64 {
65 	struct inode* inode = page->mapping->host;
66 	struct ceph_inode_info *ci = ceph_inode(inode);
67 	return fscache_maybe_release_page(ci->fscache, page, gfp);
68 }
69 
70 static inline void ceph_fscache_readpage_cancel(struct inode *inode,
71 						struct page *page)
72 {
73 	struct ceph_inode_info *ci = ceph_inode(inode);
74 	if (fscache_cookie_valid(ci->fscache) && PageFsCache(page))
75 		__fscache_uncache_page(ci->fscache, page);
76 }
77 
78 static inline void ceph_fscache_readpages_cancel(struct inode *inode,
79 						 struct list_head *pages)
80 {
81 	struct ceph_inode_info *ci = ceph_inode(inode);
82 	return fscache_readpages_cancel(ci->fscache, pages);
83 }
84 
85 #else
86 
87 static inline int ceph_fscache_register(void)
88 {
89 	return 0;
90 }
91 
92 static inline void ceph_fscache_unregister(void)
93 {
94 }
95 
96 static inline int ceph_fscache_register_fs(struct ceph_fs_client* fsc)
97 {
98 	return 0;
99 }
100 
101 static inline void ceph_fscache_unregister_fs(struct ceph_fs_client* fsc)
102 {
103 }
104 
105 static inline void ceph_fscache_inode_init(struct ceph_inode_info *ci)
106 {
107 }
108 
109 static inline void ceph_fscache_register_inode_cookie(struct ceph_fs_client* parent_fsc,
110 						      struct ceph_inode_info* ci)
111 {
112 }
113 
114 static inline void ceph_fscache_uncache_page(struct inode *inode,
115 					     struct page *pages)
116 {
117 }
118 
119 static inline int ceph_readpage_from_fscache(struct inode* inode,
120 					     struct page *page)
121 {
122 	return -ENOBUFS;
123 }
124 
125 static inline int ceph_readpages_from_fscache(struct inode *inode,
126 					      struct address_space *mapping,
127 					      struct list_head *pages,
128 					      unsigned *nr_pages)
129 {
130 	return -ENOBUFS;
131 }
132 
133 static inline void ceph_readpage_to_fscache(struct inode *inode,
134 					    struct page *page)
135 {
136 }
137 
138 static inline void ceph_fscache_invalidate(struct inode *inode)
139 {
140 }
141 
142 static inline void ceph_invalidate_fscache_page(struct inode *inode,
143 						struct page *page)
144 {
145 }
146 
147 static inline void ceph_fscache_unregister_inode_cookie(struct ceph_inode_info* ci)
148 {
149 }
150 
151 static inline int ceph_release_fscache_page(struct page *page, gfp_t gfp)
152 {
153 	return 1;
154 }
155 
156 static inline void ceph_fscache_readpage_cancel(struct inode *inode,
157 						struct page *page)
158 {
159 }
160 
161 static inline void ceph_fscache_readpages_cancel(struct inode *inode,
162 						 struct list_head *pages)
163 {
164 }
165 
166 static inline void ceph_queue_revalidate(struct inode *inode)
167 {
168 }
169 
170 #endif
171 
172 #endif
173