xref: /linux/fs/smb/client/fscache.h (revision da5b2ad1c2f18834cb1ce429e2e5a5cf5cbdf21b)
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
49 void cifs_fscache_fill_coherency(struct inode *inode,
50 				 struct cifs_fscache_inode_coherency_data *cd)
51 {
52 	struct timespec64 ctime = inode_get_ctime(inode);
53 	struct timespec64 mtime = inode_get_mtime(inode);
54 
55 	memset(cd, 0, sizeof(*cd));
56 	cd->last_write_time_sec   = cpu_to_le64(mtime.tv_sec);
57 	cd->last_write_time_nsec  = cpu_to_le32(mtime.tv_nsec);
58 	cd->last_change_time_sec  = cpu_to_le64(ctime.tv_sec);
59 	cd->last_change_time_nsec = cpu_to_le32(ctime.tv_nsec);
60 }
61 
62 
63 static inline struct fscache_cookie *cifs_inode_cookie(struct inode *inode)
64 {
65 	return netfs_i_cookie(&CIFS_I(inode)->netfs);
66 }
67 
68 static inline void cifs_invalidate_cache(struct inode *inode, unsigned int flags)
69 {
70 	struct cifs_fscache_inode_coherency_data cd;
71 
72 	cifs_fscache_fill_coherency(inode, &cd);
73 	fscache_invalidate(cifs_inode_cookie(inode), &cd,
74 			   i_size_read(inode), flags);
75 }
76 
77 static inline bool cifs_fscache_enabled(struct inode *inode)
78 {
79 	return fscache_cookie_enabled(cifs_inode_cookie(inode));
80 }
81 
82 #else /* CONFIG_CIFS_FSCACHE */
83 static inline
84 void cifs_fscache_fill_coherency(struct inode *inode,
85 				 struct cifs_fscache_inode_coherency_data *cd)
86 {
87 }
88 
89 static inline int cifs_fscache_get_super_cookie(struct cifs_tcon *tcon) { return 0; }
90 static inline void cifs_fscache_release_super_cookie(struct cifs_tcon *tcon) {}
91 
92 static inline void cifs_fscache_get_inode_cookie(struct inode *inode) {}
93 static inline void cifs_fscache_release_inode_cookie(struct inode *inode) {}
94 static inline void cifs_fscache_unuse_inode_cookie(struct inode *inode, bool update) {}
95 static inline struct fscache_cookie *cifs_inode_cookie(struct inode *inode) { return NULL; }
96 static inline void cifs_invalidate_cache(struct inode *inode, unsigned int flags) {}
97 static inline bool cifs_fscache_enabled(struct inode *inode) { return false; }
98 
99 #endif /* CONFIG_CIFS_FSCACHE */
100 
101 #endif /* _CIFS_FSCACHE_H */
102