1 /* SPDX-License-Identifier: LGPL-2.1 */
2 /*
3 * CIFS filesystem cache interface definitions
4 *
5 * Copyright (c) 2010 Novell, Inc.
6 * Authors(s): Suresh Jayaraman (sjayaraman@suse.de>
7 *
8 */
9 #ifndef _CIFS_FSCACHE_H
10 #define _CIFS_FSCACHE_H
11
12 #include <linux/swap.h>
13 #include <linux/fscache.h>
14
15 #include "cifsglob.h"
16
17 /*
18 * Coherency data attached to CIFS volume within the cache
19 */
20 struct cifs_fscache_volume_coherency_data {
21 __le64 resource_id; /* unique server resource id */
22 __le64 vol_create_time;
23 __le32 vol_serial_number;
24 } __packed;
25
26 /*
27 * Coherency data attached to CIFS inode within the cache.
28 */
29 struct cifs_fscache_inode_coherency_data {
30 __le64 last_write_time_sec;
31 __le64 last_change_time_sec;
32 __le32 last_write_time_nsec;
33 __le32 last_change_time_nsec;
34 };
35
36 #ifdef CONFIG_CIFS_FSCACHE
37
38 /*
39 * fscache.c
40 */
41 extern int cifs_fscache_get_super_cookie(struct cifs_tcon *);
42 extern void cifs_fscache_release_super_cookie(struct cifs_tcon *);
43
44 extern void cifs_fscache_get_inode_cookie(struct inode *inode);
45 extern void cifs_fscache_release_inode_cookie(struct inode *);
46 extern void cifs_fscache_unuse_inode_cookie(struct inode *inode, bool update);
47
48 static inline
cifs_fscache_fill_coherency(struct inode * inode,struct cifs_fscache_inode_coherency_data * cd)49 void cifs_fscache_fill_coherency(struct inode *inode,
50 struct cifs_fscache_inode_coherency_data *cd)
51 {
52 struct cifsInodeInfo *cifsi = CIFS_I(inode);
53
54 memset(cd, 0, sizeof(*cd));
55 cd->last_write_time_sec = cpu_to_le64(cifsi->netfs.inode.i_mtime.tv_sec);
56 cd->last_write_time_nsec = cpu_to_le32(cifsi->netfs.inode.i_mtime.tv_nsec);
57 cd->last_change_time_sec = cpu_to_le64(cifsi->netfs.inode.i_ctime.tv_sec);
58 cd->last_change_time_nsec = cpu_to_le32(cifsi->netfs.inode.i_ctime.tv_nsec);
59 }
60
61
cifs_inode_cookie(struct inode * inode)62 static inline struct fscache_cookie *cifs_inode_cookie(struct inode *inode)
63 {
64 return netfs_i_cookie(&CIFS_I(inode)->netfs);
65 }
66
cifs_invalidate_cache(struct inode * inode,unsigned int flags)67 static inline void cifs_invalidate_cache(struct inode *inode, unsigned int flags)
68 {
69 struct cifs_fscache_inode_coherency_data cd;
70
71 cifs_fscache_fill_coherency(inode, &cd);
72 fscache_invalidate(cifs_inode_cookie(inode), &cd,
73 i_size_read(inode), flags);
74 }
75
76 extern int __cifs_fscache_query_occupancy(struct inode *inode,
77 pgoff_t first, unsigned int nr_pages,
78 pgoff_t *_data_first,
79 unsigned int *_data_nr_pages);
80
cifs_fscache_query_occupancy(struct inode * inode,pgoff_t first,unsigned int nr_pages,pgoff_t * _data_first,unsigned int * _data_nr_pages)81 static inline int cifs_fscache_query_occupancy(struct inode *inode,
82 pgoff_t first, unsigned int nr_pages,
83 pgoff_t *_data_first,
84 unsigned int *_data_nr_pages)
85 {
86 if (!cifs_inode_cookie(inode))
87 return -ENOBUFS;
88 return __cifs_fscache_query_occupancy(inode, first, nr_pages,
89 _data_first, _data_nr_pages);
90 }
91
92 extern int __cifs_readpage_from_fscache(struct inode *pinode, struct page *ppage);
93 extern void __cifs_readpage_to_fscache(struct inode *pinode, struct page *ppage);
94
95
cifs_readpage_from_fscache(struct inode * inode,struct page * page)96 static inline int cifs_readpage_from_fscache(struct inode *inode,
97 struct page *page)
98 {
99 if (cifs_inode_cookie(inode))
100 return __cifs_readpage_from_fscache(inode, page);
101 return -ENOBUFS;
102 }
103
cifs_readpage_to_fscache(struct inode * inode,struct page * page)104 static inline void cifs_readpage_to_fscache(struct inode *inode,
105 struct page *page)
106 {
107 if (cifs_inode_cookie(inode))
108 __cifs_readpage_to_fscache(inode, page);
109 }
110
cifs_fscache_release_page(struct page * page,gfp_t gfp)111 static inline int cifs_fscache_release_page(struct page *page, gfp_t gfp)
112 {
113 if (PageFsCache(page)) {
114 if (current_is_kswapd() || !(gfp & __GFP_FS))
115 return false;
116 wait_on_page_fscache(page);
117 fscache_note_page_release(cifs_inode_cookie(page->mapping->host));
118 }
119 return true;
120 }
121
122 #else /* CONFIG_CIFS_FSCACHE */
123 static inline
cifs_fscache_fill_coherency(struct inode * inode,struct cifs_fscache_inode_coherency_data * cd)124 void cifs_fscache_fill_coherency(struct inode *inode,
125 struct cifs_fscache_inode_coherency_data *cd)
126 {
127 }
128
cifs_fscache_get_super_cookie(struct cifs_tcon * tcon)129 static inline int cifs_fscache_get_super_cookie(struct cifs_tcon *tcon) { return 0; }
cifs_fscache_release_super_cookie(struct cifs_tcon * tcon)130 static inline void cifs_fscache_release_super_cookie(struct cifs_tcon *tcon) {}
131
cifs_fscache_get_inode_cookie(struct inode * inode)132 static inline void cifs_fscache_get_inode_cookie(struct inode *inode) {}
cifs_fscache_release_inode_cookie(struct inode * inode)133 static inline void cifs_fscache_release_inode_cookie(struct inode *inode) {}
cifs_fscache_unuse_inode_cookie(struct inode * inode,bool update)134 static inline void cifs_fscache_unuse_inode_cookie(struct inode *inode, bool update) {}
cifs_inode_cookie(struct inode * inode)135 static inline struct fscache_cookie *cifs_inode_cookie(struct inode *inode) { return NULL; }
cifs_invalidate_cache(struct inode * inode,unsigned int flags)136 static inline void cifs_invalidate_cache(struct inode *inode, unsigned int flags) {}
137
cifs_fscache_query_occupancy(struct inode * inode,pgoff_t first,unsigned int nr_pages,pgoff_t * _data_first,unsigned int * _data_nr_pages)138 static inline int cifs_fscache_query_occupancy(struct inode *inode,
139 pgoff_t first, unsigned int nr_pages,
140 pgoff_t *_data_first,
141 unsigned int *_data_nr_pages)
142 {
143 *_data_first = ULONG_MAX;
144 *_data_nr_pages = 0;
145 return -ENOBUFS;
146 }
147
148 static inline int
cifs_readpage_from_fscache(struct inode * inode,struct page * page)149 cifs_readpage_from_fscache(struct inode *inode, struct page *page)
150 {
151 return -ENOBUFS;
152 }
153
154 static inline
cifs_readpage_to_fscache(struct inode * inode,struct page * page)155 void cifs_readpage_to_fscache(struct inode *inode, struct page *page) {}
156
nfs_fscache_release_page(struct page * page,gfp_t gfp)157 static inline int nfs_fscache_release_page(struct page *page, gfp_t gfp)
158 {
159 return true; /* May release page */
160 }
161
162 #endif /* CONFIG_CIFS_FSCACHE */
163
164 #endif /* _CIFS_FSCACHE_H */
165