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14#include <linux/module.h>
15#include <linux/fs.h>
16#include <linux/exportfs.h>
17#include <linux/mm.h>
18#include <linux/cleancache.h>
19
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26
27int cleancache_enabled;
28EXPORT_SYMBOL(cleancache_enabled);
29
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31
32
33
34static struct cleancache_ops cleancache_ops;
35
36
37static unsigned long cleancache_succ_gets;
38static unsigned long cleancache_failed_gets;
39static unsigned long cleancache_puts;
40static unsigned long cleancache_flushes;
41
42
43
44
45
46struct cleancache_ops cleancache_register_ops(struct cleancache_ops *ops)
47{
48 struct cleancache_ops old = cleancache_ops;
49
50 cleancache_ops = *ops;
51 cleancache_enabled = 1;
52 return old;
53}
54EXPORT_SYMBOL(cleancache_register_ops);
55
56
57void __cleancache_init_fs(struct super_block *sb)
58{
59 sb->cleancache_poolid = (*cleancache_ops.init_fs)(PAGE_SIZE);
60}
61EXPORT_SYMBOL(__cleancache_init_fs);
62
63
64void __cleancache_init_shared_fs(char *uuid, struct super_block *sb)
65{
66 sb->cleancache_poolid =
67 (*cleancache_ops.init_shared_fs)(uuid, PAGE_SIZE);
68}
69EXPORT_SYMBOL(__cleancache_init_shared_fs);
70
71
72
73
74
75static int cleancache_get_key(struct inode *inode,
76 struct cleancache_filekey *key)
77{
78 int (*fhfn)(struct dentry *, __u32 *fh, int *, int);
79 int len = 0, maxlen = CLEANCACHE_KEY_MAX;
80 struct super_block *sb = inode->i_sb;
81
82 key->u.ino = inode->i_ino;
83 if (sb->s_export_op != NULL) {
84 fhfn = sb->s_export_op->encode_fh;
85 if (fhfn) {
86 struct dentry d;
87 d.d_inode = inode;
88 len = (*fhfn)(&d, &key->u.fh[0], &maxlen, 0);
89 if (len <= 0 || len == 255)
90 return -1;
91 if (maxlen > CLEANCACHE_KEY_MAX)
92 return -1;
93 }
94 }
95 return 0;
96}
97
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102
103
104
105int __cleancache_get_page(struct page *page)
106{
107 int ret = -1;
108 int pool_id;
109 struct cleancache_filekey key = { .u.key = { 0 } };
110
111 VM_BUG_ON(!PageLocked(page));
112 pool_id = page->mapping->host->i_sb->cleancache_poolid;
113 if (pool_id < 0)
114 goto out;
115
116 if (cleancache_get_key(page->mapping->host, &key) < 0)
117 goto out;
118
119 ret = (*cleancache_ops.get_page)(pool_id, key, page->index, page);
120 if (ret == 0)
121 cleancache_succ_gets++;
122 else
123 cleancache_failed_gets++;
124out:
125 return ret;
126}
127EXPORT_SYMBOL(__cleancache_get_page);
128
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133
134
135void __cleancache_put_page(struct page *page)
136{
137 int pool_id;
138 struct cleancache_filekey key = { .u.key = { 0 } };
139
140 VM_BUG_ON(!PageLocked(page));
141 pool_id = page->mapping->host->i_sb->cleancache_poolid;
142 if (pool_id >= 0 &&
143 cleancache_get_key(page->mapping->host, &key) >= 0) {
144 (*cleancache_ops.put_page)(pool_id, key, page->index, page);
145 cleancache_puts++;
146 }
147}
148EXPORT_SYMBOL(__cleancache_put_page);
149
150
151
152
153
154void __cleancache_flush_page(struct address_space *mapping, struct page *page)
155{
156
157 int pool_id = mapping->host->i_sb->cleancache_poolid;
158 struct cleancache_filekey key = { .u.key = { 0 } };
159
160 if (pool_id >= 0) {
161 VM_BUG_ON(!PageLocked(page));
162 if (cleancache_get_key(mapping->host, &key) >= 0) {
163 (*cleancache_ops.flush_page)(pool_id, key, page->index);
164 cleancache_flushes++;
165 }
166 }
167}
168EXPORT_SYMBOL(__cleancache_flush_page);
169
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173
174
175void __cleancache_flush_inode(struct address_space *mapping)
176{
177 int pool_id = mapping->host->i_sb->cleancache_poolid;
178 struct cleancache_filekey key = { .u.key = { 0 } };
179
180 if (pool_id >= 0 && cleancache_get_key(mapping->host, &key) >= 0)
181 (*cleancache_ops.flush_inode)(pool_id, key);
182}
183EXPORT_SYMBOL(__cleancache_flush_inode);
184
185
186
187
188
189
190void __cleancache_flush_fs(struct super_block *sb)
191{
192 if (sb->cleancache_poolid >= 0) {
193 int old_poolid = sb->cleancache_poolid;
194 sb->cleancache_poolid = -1;
195 (*cleancache_ops.flush_fs)(old_poolid);
196 }
197}
198EXPORT_SYMBOL(__cleancache_flush_fs);
199
200#ifdef CONFIG_SYSFS
201
202
203
204#define CLEANCACHE_SYSFS_RO(_name) \
205 static ssize_t cleancache_##_name##_show(struct kobject *kobj, \
206 struct kobj_attribute *attr, char *buf) \
207 { \
208 return sprintf(buf, "%lu\n", cleancache_##_name); \
209 } \
210 static struct kobj_attribute cleancache_##_name##_attr = { \
211 .attr = { .name = __stringify(_name), .mode = 0444 }, \
212 .show = cleancache_##_name##_show, \
213 }
214
215CLEANCACHE_SYSFS_RO(succ_gets);
216CLEANCACHE_SYSFS_RO(failed_gets);
217CLEANCACHE_SYSFS_RO(puts);
218CLEANCACHE_SYSFS_RO(flushes);
219
220static struct attribute *cleancache_attrs[] = {
221 &cleancache_succ_gets_attr.attr,
222 &cleancache_failed_gets_attr.attr,
223 &cleancache_puts_attr.attr,
224 &cleancache_flushes_attr.attr,
225 NULL,
226};
227
228static struct attribute_group cleancache_attr_group = {
229 .attrs = cleancache_attrs,
230 .name = "cleancache",
231};
232
233#endif
234
235static int __init init_cleancache(void)
236{
237#ifdef CONFIG_SYSFS
238 int err;
239
240 err = sysfs_create_group(mm_kobj, &cleancache_attr_group);
241#endif
242 return 0;
243}
244module_init(init_cleancache)
245