Commit | Line | Data |
---|---|---|
077b1f83 DM |
1 | #ifndef _LINUX_CLEANCACHE_H |
2 | #define _LINUX_CLEANCACHE_H | |
3 | ||
4 | #include <linux/fs.h> | |
5 | #include <linux/exportfs.h> | |
6 | #include <linux/mm.h> | |
7 | ||
8 | #define CLEANCACHE_KEY_MAX 6 | |
9 | ||
10 | /* | |
11 | * cleancache requires every file with a page in cleancache to have a | |
12 | * unique key unless/until the file is removed/truncated. For some | |
13 | * filesystems, the inode number is unique, but for "modern" filesystems | |
14 | * an exportable filehandle is required (see exportfs.h) | |
15 | */ | |
16 | struct cleancache_filekey { | |
17 | union { | |
18 | ino_t ino; | |
19 | __u32 fh[CLEANCACHE_KEY_MAX]; | |
20 | u32 key[CLEANCACHE_KEY_MAX]; | |
21 | } u; | |
22 | }; | |
23 | ||
24 | struct cleancache_ops { | |
25 | int (*init_fs)(size_t); | |
26 | int (*init_shared_fs)(char *uuid, size_t); | |
27 | int (*get_page)(int, struct cleancache_filekey, | |
28 | pgoff_t, struct page *); | |
29 | void (*put_page)(int, struct cleancache_filekey, | |
30 | pgoff_t, struct page *); | |
91c6cc9b DM |
31 | void (*invalidate_page)(int, struct cleancache_filekey, pgoff_t); |
32 | void (*invalidate_inode)(int, struct cleancache_filekey); | |
33 | void (*invalidate_fs)(int); | |
077b1f83 DM |
34 | }; |
35 | ||
53d85c98 | 36 | extern int cleancache_register_ops(struct cleancache_ops *ops); |
077b1f83 | 37 | extern void __cleancache_init_fs(struct super_block *); |
9de16262 | 38 | extern void __cleancache_init_shared_fs(struct super_block *); |
077b1f83 DM |
39 | extern int __cleancache_get_page(struct page *); |
40 | extern void __cleancache_put_page(struct page *); | |
3167760f DM |
41 | extern void __cleancache_invalidate_page(struct address_space *, struct page *); |
42 | extern void __cleancache_invalidate_inode(struct address_space *); | |
43 | extern void __cleancache_invalidate_fs(struct super_block *); | |
077b1f83 DM |
44 | |
45 | #ifdef CONFIG_CLEANCACHE | |
ff610a1d | 46 | #define cleancache_enabled (1) |
077b1f83 DM |
47 | static inline bool cleancache_fs_enabled(struct page *page) |
48 | { | |
49 | return page->mapping->host->i_sb->cleancache_poolid >= 0; | |
50 | } | |
51 | static inline bool cleancache_fs_enabled_mapping(struct address_space *mapping) | |
52 | { | |
53 | return mapping->host->i_sb->cleancache_poolid >= 0; | |
54 | } | |
55 | #else | |
56 | #define cleancache_enabled (0) | |
57 | #define cleancache_fs_enabled(_page) (0) | |
58 | #define cleancache_fs_enabled_mapping(_page) (0) | |
59 | #endif | |
60 | ||
61 | /* | |
62 | * The shim layer provided by these inline functions allows the compiler | |
63 | * to reduce all cleancache hooks to nothingness if CONFIG_CLEANCACHE | |
64 | * is disabled, to a single global variable check if CONFIG_CLEANCACHE | |
65 | * is enabled but no cleancache "backend" has dynamically enabled it, | |
66 | * and, for the most frequent cleancache ops, to a single global variable | |
67 | * check plus a superblock element comparison if CONFIG_CLEANCACHE is enabled | |
68 | * and a cleancache backend has dynamically enabled cleancache, but the | |
69 | * filesystem referenced by that cleancache op has not enabled cleancache. | |
70 | * As a result, CONFIG_CLEANCACHE can be enabled by default with essentially | |
71 | * no measurable performance impact. | |
72 | */ | |
73 | ||
74 | static inline void cleancache_init_fs(struct super_block *sb) | |
75 | { | |
76 | if (cleancache_enabled) | |
77 | __cleancache_init_fs(sb); | |
78 | } | |
79 | ||
9de16262 | 80 | static inline void cleancache_init_shared_fs(struct super_block *sb) |
077b1f83 DM |
81 | { |
82 | if (cleancache_enabled) | |
9de16262 | 83 | __cleancache_init_shared_fs(sb); |
077b1f83 DM |
84 | } |
85 | ||
86 | static inline int cleancache_get_page(struct page *page) | |
87 | { | |
88 | int ret = -1; | |
89 | ||
90 | if (cleancache_enabled && cleancache_fs_enabled(page)) | |
91 | ret = __cleancache_get_page(page); | |
92 | return ret; | |
93 | } | |
94 | ||
95 | static inline void cleancache_put_page(struct page *page) | |
96 | { | |
97 | if (cleancache_enabled && cleancache_fs_enabled(page)) | |
98 | __cleancache_put_page(page); | |
99 | } | |
100 | ||
3167760f | 101 | static inline void cleancache_invalidate_page(struct address_space *mapping, |
077b1f83 DM |
102 | struct page *page) |
103 | { | |
104 | /* careful... page->mapping is NULL sometimes when this is called */ | |
105 | if (cleancache_enabled && cleancache_fs_enabled_mapping(mapping)) | |
3167760f | 106 | __cleancache_invalidate_page(mapping, page); |
077b1f83 DM |
107 | } |
108 | ||
3167760f | 109 | static inline void cleancache_invalidate_inode(struct address_space *mapping) |
077b1f83 DM |
110 | { |
111 | if (cleancache_enabled && cleancache_fs_enabled_mapping(mapping)) | |
3167760f | 112 | __cleancache_invalidate_inode(mapping); |
077b1f83 DM |
113 | } |
114 | ||
3167760f | 115 | static inline void cleancache_invalidate_fs(struct super_block *sb) |
077b1f83 DM |
116 | { |
117 | if (cleancache_enabled) | |
3167760f | 118 | __cleancache_invalidate_fs(sb); |
077b1f83 DM |
119 | } |
120 | ||
121 | #endif /* _LINUX_CLEANCACHE_H */ |