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9#include <linux/ceph/ceph_debug.h>
10
11#include <linux/fs_context.h>
12#include "super.h"
13#include "cache.h"
14
15struct ceph_aux_inode {
16 u64 version;
17 u64 mtime_sec;
18 u64 mtime_nsec;
19};
20
21struct fscache_netfs ceph_cache_netfs = {
22 .name = "ceph",
23 .version = 0,
24};
25
26static DEFINE_MUTEX(ceph_fscache_lock);
27static LIST_HEAD(ceph_fscache_list);
28
29struct ceph_fscache_entry {
30 struct list_head list;
31 struct fscache_cookie *fscache;
32 size_t uniq_len;
33
34 struct ceph_fsid fsid;
35 char uniquifier[];
36};
37
38static const struct fscache_cookie_def ceph_fscache_fsid_object_def = {
39 .name = "CEPH.fsid",
40 .type = FSCACHE_COOKIE_TYPE_INDEX,
41};
42
43int __init ceph_fscache_register(void)
44{
45 return fscache_register_netfs(&ceph_cache_netfs);
46}
47
48void ceph_fscache_unregister(void)
49{
50 fscache_unregister_netfs(&ceph_cache_netfs);
51}
52
53int ceph_fscache_register_fs(struct ceph_fs_client* fsc, struct fs_context *fc)
54{
55 const struct ceph_fsid *fsid = &fsc->client->fsid;
56 const char *fscache_uniq = fsc->mount_options->fscache_uniq;
57 size_t uniq_len = fscache_uniq ? strlen(fscache_uniq) : 0;
58 struct ceph_fscache_entry *ent;
59 int err = 0;
60
61 mutex_lock(&ceph_fscache_lock);
62 list_for_each_entry(ent, &ceph_fscache_list, list) {
63 if (memcmp(&ent->fsid, fsid, sizeof(*fsid)))
64 continue;
65 if (ent->uniq_len != uniq_len)
66 continue;
67 if (uniq_len && memcmp(ent->uniquifier, fscache_uniq, uniq_len))
68 continue;
69
70 errorfc(fc, "fscache cookie already registered for fsid %pU, use fsc=<uniquifier> option",
71 fsid);
72 err = -EBUSY;
73 goto out_unlock;
74 }
75
76 ent = kzalloc(sizeof(*ent) + uniq_len, GFP_KERNEL);
77 if (!ent) {
78 err = -ENOMEM;
79 goto out_unlock;
80 }
81
82 memcpy(&ent->fsid, fsid, sizeof(*fsid));
83 if (uniq_len > 0) {
84 memcpy(&ent->uniquifier, fscache_uniq, uniq_len);
85 ent->uniq_len = uniq_len;
86 }
87
88 fsc->fscache = fscache_acquire_cookie(ceph_cache_netfs.primary_index,
89 &ceph_fscache_fsid_object_def,
90 &ent->fsid, sizeof(ent->fsid) + uniq_len,
91 NULL, 0,
92 fsc, 0, true);
93
94 if (fsc->fscache) {
95 ent->fscache = fsc->fscache;
96 list_add_tail(&ent->list, &ceph_fscache_list);
97 } else {
98 kfree(ent);
99 errorfc(fc, "unable to register fscache cookie for fsid %pU",
100 fsid);
101
102 }
103out_unlock:
104 mutex_unlock(&ceph_fscache_lock);
105 return err;
106}
107
108static enum fscache_checkaux ceph_fscache_inode_check_aux(
109 void *cookie_netfs_data, const void *data, uint16_t dlen,
110 loff_t object_size)
111{
112 struct ceph_aux_inode aux;
113 struct ceph_inode_info* ci = cookie_netfs_data;
114 struct inode* inode = &ci->vfs_inode;
115
116 if (dlen != sizeof(aux) ||
117 i_size_read(inode) != object_size)
118 return FSCACHE_CHECKAUX_OBSOLETE;
119
120 memset(&aux, 0, sizeof(aux));
121 aux.version = ci->i_version;
122 aux.mtime_sec = inode->i_mtime.tv_sec;
123 aux.mtime_nsec = inode->i_mtime.tv_nsec;
124
125 if (memcmp(data, &aux, sizeof(aux)) != 0)
126 return FSCACHE_CHECKAUX_OBSOLETE;
127
128 dout("ceph inode 0x%p cached okay\n", ci);
129 return FSCACHE_CHECKAUX_OKAY;
130}
131
132static const struct fscache_cookie_def ceph_fscache_inode_object_def = {
133 .name = "CEPH.inode",
134 .type = FSCACHE_COOKIE_TYPE_DATAFILE,
135 .check_aux = ceph_fscache_inode_check_aux,
136};
137
138void ceph_fscache_register_inode_cookie(struct inode *inode)
139{
140 struct ceph_inode_info *ci = ceph_inode(inode);
141 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
142 struct ceph_aux_inode aux;
143
144
145 if (!fsc->fscache)
146 return;
147
148
149 if (!S_ISREG(inode->i_mode))
150 return;
151
152 inode_lock_nested(inode, I_MUTEX_CHILD);
153 if (!ci->fscache) {
154 memset(&aux, 0, sizeof(aux));
155 aux.version = ci->i_version;
156 aux.mtime_sec = inode->i_mtime.tv_sec;
157 aux.mtime_nsec = inode->i_mtime.tv_nsec;
158 ci->fscache = fscache_acquire_cookie(fsc->fscache,
159 &ceph_fscache_inode_object_def,
160 &ci->i_vino, sizeof(ci->i_vino),
161 &aux, sizeof(aux),
162 ci, i_size_read(inode), false);
163 }
164 inode_unlock(inode);
165}
166
167void ceph_fscache_unregister_inode_cookie(struct ceph_inode_info* ci)
168{
169 struct fscache_cookie* cookie;
170
171 if ((cookie = ci->fscache) == NULL)
172 return;
173
174 ci->fscache = NULL;
175
176 fscache_relinquish_cookie(cookie, &ci->i_vino, false);
177}
178
179static bool ceph_fscache_can_enable(void *data)
180{
181 struct inode *inode = data;
182 return !inode_is_open_for_write(inode);
183}
184
185void ceph_fscache_file_set_cookie(struct inode *inode, struct file *filp)
186{
187 struct ceph_inode_info *ci = ceph_inode(inode);
188
189 if (!fscache_cookie_valid(ci->fscache))
190 return;
191
192 if (inode_is_open_for_write(inode)) {
193 dout("fscache_file_set_cookie %p %p disabling cache\n",
194 inode, filp);
195 fscache_disable_cookie(ci->fscache, &ci->i_vino, false);
196 } else {
197 fscache_enable_cookie(ci->fscache, &ci->i_vino, i_size_read(inode),
198 ceph_fscache_can_enable, inode);
199 if (fscache_cookie_enabled(ci->fscache)) {
200 dout("fscache_file_set_cookie %p %p enabling cache\n",
201 inode, filp);
202 }
203 }
204}
205
206void ceph_fscache_unregister_fs(struct ceph_fs_client* fsc)
207{
208 if (fscache_cookie_valid(fsc->fscache)) {
209 struct ceph_fscache_entry *ent;
210 bool found = false;
211
212 mutex_lock(&ceph_fscache_lock);
213 list_for_each_entry(ent, &ceph_fscache_list, list) {
214 if (ent->fscache == fsc->fscache) {
215 list_del(&ent->list);
216 kfree(ent);
217 found = true;
218 break;
219 }
220 }
221 WARN_ON_ONCE(!found);
222 mutex_unlock(&ceph_fscache_lock);
223
224 __fscache_relinquish_cookie(fsc->fscache, NULL, false);
225 }
226 fsc->fscache = NULL;
227}
228
