1 /*
2 * fs/cifs/fscache.c - CIFS filesystem cache interface
3 *
4 * Copyright (c) 2010 Novell, Inc.
5 * Author(s): Suresh Jayaraman <sjayaraman@suse.de>
6 *
7 * This library is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU Lesser General Public License as published
9 * by the Free Software Foundation; either version 2.1 of the License, or
10 * (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
15 * the GNU Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this library; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21 #include "fscache.h"
22 #include "cifsglob.h"
23 #include "cifs_debug.h"
24 #include "cifs_fs_sb.h"
25
26 /*
27 * Key layout of CIFS server cache index object
28 */
29 struct cifs_server_key {
30 struct {
31 uint16_t family; /* address family */
32 __be16 port; /* IP port */
33 } hdr;
34 union {
35 struct in_addr ipv4_addr;
36 struct in6_addr ipv6_addr;
37 };
38 } __packed;
39
40 /*
41 * Get a cookie for a server object keyed by {IPaddress,port,family} tuple
42 */
cifs_fscache_get_client_cookie(struct TCP_Server_Info * server)43 void cifs_fscache_get_client_cookie(struct TCP_Server_Info *server)
44 {
45 const struct sockaddr *sa = (struct sockaddr *) &server->dstaddr;
46 const struct sockaddr_in *addr = (struct sockaddr_in *) sa;
47 const struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *) sa;
48 struct cifs_server_key key;
49 uint16_t key_len = sizeof(key.hdr);
50
51 memset(&key, 0, sizeof(key));
52
53 /*
54 * Should not be a problem as sin_family/sin6_family overlays
55 * sa_family field
56 */
57 key.hdr.family = sa->sa_family;
58 switch (sa->sa_family) {
59 case AF_INET:
60 key.hdr.port = addr->sin_port;
61 key.ipv4_addr = addr->sin_addr;
62 key_len += sizeof(key.ipv4_addr);
63 break;
64
65 case AF_INET6:
66 key.hdr.port = addr6->sin6_port;
67 key.ipv6_addr = addr6->sin6_addr;
68 key_len += sizeof(key.ipv6_addr);
69 break;
70
71 default:
72 cifs_dbg(VFS, "Unknown network family '%d'\n", sa->sa_family);
73 server->fscache = NULL;
74 return;
75 }
76
77 server->fscache =
78 fscache_acquire_cookie(cifs_fscache_netfs.primary_index,
79 &cifs_fscache_server_index_def,
80 &key, key_len,
81 NULL, 0,
82 server, 0, true);
83 cifs_dbg(FYI, "%s: (0x%p/0x%p)\n",
84 __func__, server, server->fscache);
85 }
86
cifs_fscache_release_client_cookie(struct TCP_Server_Info * server)87 void cifs_fscache_release_client_cookie(struct TCP_Server_Info *server)
88 {
89 cifs_dbg(FYI, "%s: (0x%p/0x%p)\n",
90 __func__, server, server->fscache);
91 fscache_relinquish_cookie(server->fscache, NULL, false);
92 server->fscache = NULL;
93 }
94
cifs_fscache_get_super_cookie(struct cifs_tcon * tcon)95 void cifs_fscache_get_super_cookie(struct cifs_tcon *tcon)
96 {
97 struct TCP_Server_Info *server = tcon->ses->server;
98 char *sharename;
99 struct cifs_fscache_super_auxdata auxdata;
100
101 sharename = extract_sharename(tcon->treeName);
102 if (IS_ERR(sharename)) {
103 cifs_dbg(FYI, "%s: couldn't extract sharename\n", __func__);
104 tcon->fscache = NULL;
105 return;
106 }
107
108 memset(&auxdata, 0, sizeof(auxdata));
109 auxdata.resource_id = tcon->resource_id;
110 auxdata.vol_create_time = tcon->vol_create_time;
111 auxdata.vol_serial_number = tcon->vol_serial_number;
112
113 tcon->fscache =
114 fscache_acquire_cookie(server->fscache,
115 &cifs_fscache_super_index_def,
116 sharename, strlen(sharename),
117 &auxdata, sizeof(auxdata),
118 tcon, 0, true);
119 kfree(sharename);
120 cifs_dbg(FYI, "%s: (0x%p/0x%p)\n",
121 __func__, server->fscache, tcon->fscache);
122 }
123
cifs_fscache_release_super_cookie(struct cifs_tcon * tcon)124 void cifs_fscache_release_super_cookie(struct cifs_tcon *tcon)
125 {
126 struct cifs_fscache_super_auxdata auxdata;
127
128 memset(&auxdata, 0, sizeof(auxdata));
129 auxdata.resource_id = tcon->resource_id;
130 auxdata.vol_create_time = tcon->vol_create_time;
131 auxdata.vol_serial_number = tcon->vol_serial_number;
132
133 cifs_dbg(FYI, "%s: (0x%p)\n", __func__, tcon->fscache);
134 fscache_relinquish_cookie(tcon->fscache, &auxdata, false);
135 tcon->fscache = NULL;
136 }
137
cifs_fscache_acquire_inode_cookie(struct cifsInodeInfo * cifsi,struct cifs_tcon * tcon)138 static void cifs_fscache_acquire_inode_cookie(struct cifsInodeInfo *cifsi,
139 struct cifs_tcon *tcon)
140 {
141 struct cifs_fscache_inode_auxdata auxdata;
142
143 memset(&auxdata, 0, sizeof(auxdata));
144 auxdata.eof = cifsi->server_eof;
145 auxdata.last_write_time_sec = cifsi->vfs_inode.i_mtime.tv_sec;
146 auxdata.last_change_time_sec = cifsi->vfs_inode.i_ctime.tv_sec;
147 auxdata.last_write_time_nsec = cifsi->vfs_inode.i_mtime.tv_nsec;
148 auxdata.last_change_time_nsec = cifsi->vfs_inode.i_ctime.tv_nsec;
149
150 cifsi->fscache =
151 fscache_acquire_cookie(tcon->fscache,
152 &cifs_fscache_inode_object_def,
153 &cifsi->uniqueid, sizeof(cifsi->uniqueid),
154 &auxdata, sizeof(auxdata),
155 cifsi, cifsi->vfs_inode.i_size, true);
156 }
157
cifs_fscache_enable_inode_cookie(struct inode * inode)158 static void cifs_fscache_enable_inode_cookie(struct inode *inode)
159 {
160 struct cifsInodeInfo *cifsi = CIFS_I(inode);
161 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
162 struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
163
164 if (cifsi->fscache)
165 return;
166
167 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_FSCACHE))
168 return;
169
170 cifs_fscache_acquire_inode_cookie(cifsi, tcon);
171
172 cifs_dbg(FYI, "%s: got FH cookie (0x%p/0x%p)\n",
173 __func__, tcon->fscache, cifsi->fscache);
174 }
175
cifs_fscache_release_inode_cookie(struct inode * inode)176 void cifs_fscache_release_inode_cookie(struct inode *inode)
177 {
178 struct cifs_fscache_inode_auxdata auxdata;
179 struct cifsInodeInfo *cifsi = CIFS_I(inode);
180
181 if (cifsi->fscache) {
182 memset(&auxdata, 0, sizeof(auxdata));
183 auxdata.eof = cifsi->server_eof;
184 auxdata.last_write_time_sec = cifsi->vfs_inode.i_mtime.tv_sec;
185 auxdata.last_change_time_sec = cifsi->vfs_inode.i_ctime.tv_sec;
186 auxdata.last_write_time_nsec = cifsi->vfs_inode.i_mtime.tv_nsec;
187 auxdata.last_change_time_nsec = cifsi->vfs_inode.i_ctime.tv_nsec;
188
189 cifs_dbg(FYI, "%s: (0x%p)\n", __func__, cifsi->fscache);
190 fscache_relinquish_cookie(cifsi->fscache, &auxdata, false);
191 cifsi->fscache = NULL;
192 }
193 }
194
cifs_fscache_disable_inode_cookie(struct inode * inode)195 static void cifs_fscache_disable_inode_cookie(struct inode *inode)
196 {
197 struct cifsInodeInfo *cifsi = CIFS_I(inode);
198
199 if (cifsi->fscache) {
200 cifs_dbg(FYI, "%s: (0x%p)\n", __func__, cifsi->fscache);
201 fscache_uncache_all_inode_pages(cifsi->fscache, inode);
202 fscache_relinquish_cookie(cifsi->fscache, NULL, true);
203 cifsi->fscache = NULL;
204 }
205 }
206
cifs_fscache_set_inode_cookie(struct inode * inode,struct file * filp)207 void cifs_fscache_set_inode_cookie(struct inode *inode, struct file *filp)
208 {
209 if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
210 cifs_fscache_disable_inode_cookie(inode);
211 else
212 cifs_fscache_enable_inode_cookie(inode);
213 }
214
cifs_fscache_reset_inode_cookie(struct inode * inode)215 void cifs_fscache_reset_inode_cookie(struct inode *inode)
216 {
217 struct cifsInodeInfo *cifsi = CIFS_I(inode);
218 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
219 struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
220 struct fscache_cookie *old = cifsi->fscache;
221
222 if (cifsi->fscache) {
223 /* retire the current fscache cache and get a new one */
224 fscache_relinquish_cookie(cifsi->fscache, NULL, true);
225
226 cifs_fscache_acquire_inode_cookie(cifsi, tcon);
227 cifs_dbg(FYI, "%s: new cookie 0x%p oldcookie 0x%p\n",
228 __func__, cifsi->fscache, old);
229 }
230 }
231
cifs_fscache_release_page(struct page * page,gfp_t gfp)232 int cifs_fscache_release_page(struct page *page, gfp_t gfp)
233 {
234 if (PageFsCache(page)) {
235 struct inode *inode = page->mapping->host;
236 struct cifsInodeInfo *cifsi = CIFS_I(inode);
237
238 cifs_dbg(FYI, "%s: (0x%p/0x%p)\n",
239 __func__, page, cifsi->fscache);
240 if (!fscache_maybe_release_page(cifsi->fscache, page, gfp))
241 return 0;
242 }
243
244 return 1;
245 }
246
cifs_readpage_from_fscache_complete(struct page * page,void * ctx,int error)247 static void cifs_readpage_from_fscache_complete(struct page *page, void *ctx,
248 int error)
249 {
250 cifs_dbg(FYI, "%s: (0x%p/%d)\n", __func__, page, error);
251 if (!error)
252 SetPageUptodate(page);
253 unlock_page(page);
254 }
255
256 /*
257 * Retrieve a page from FS-Cache
258 */
__cifs_readpage_from_fscache(struct inode * inode,struct page * page)259 int __cifs_readpage_from_fscache(struct inode *inode, struct page *page)
260 {
261 int ret;
262
263 cifs_dbg(FYI, "%s: (fsc:%p, p:%p, i:0x%p\n",
264 __func__, CIFS_I(inode)->fscache, page, inode);
265 ret = fscache_read_or_alloc_page(CIFS_I(inode)->fscache, page,
266 cifs_readpage_from_fscache_complete,
267 NULL,
268 GFP_KERNEL);
269 switch (ret) {
270
271 case 0: /* page found in fscache, read submitted */
272 cifs_dbg(FYI, "%s: submitted\n", __func__);
273 return ret;
274 case -ENOBUFS: /* page won't be cached */
275 case -ENODATA: /* page not in cache */
276 cifs_dbg(FYI, "%s: %d\n", __func__, ret);
277 return 1;
278
279 default:
280 cifs_dbg(VFS, "unknown error ret = %d\n", ret);
281 }
282 return ret;
283 }
284
285 /*
286 * Retrieve a set of pages from FS-Cache
287 */
__cifs_readpages_from_fscache(struct inode * inode,struct address_space * mapping,struct list_head * pages,unsigned * nr_pages)288 int __cifs_readpages_from_fscache(struct inode *inode,
289 struct address_space *mapping,
290 struct list_head *pages,
291 unsigned *nr_pages)
292 {
293 int ret;
294
295 cifs_dbg(FYI, "%s: (0x%p/%u/0x%p)\n",
296 __func__, CIFS_I(inode)->fscache, *nr_pages, inode);
297 ret = fscache_read_or_alloc_pages(CIFS_I(inode)->fscache, mapping,
298 pages, nr_pages,
299 cifs_readpage_from_fscache_complete,
300 NULL,
301 mapping_gfp_mask(mapping));
302 switch (ret) {
303 case 0: /* read submitted to the cache for all pages */
304 cifs_dbg(FYI, "%s: submitted\n", __func__);
305 return ret;
306
307 case -ENOBUFS: /* some pages are not cached and can't be */
308 case -ENODATA: /* some pages are not cached */
309 cifs_dbg(FYI, "%s: no page\n", __func__);
310 return 1;
311
312 default:
313 cifs_dbg(FYI, "unknown error ret = %d\n", ret);
314 }
315
316 return ret;
317 }
318
__cifs_readpage_to_fscache(struct inode * inode,struct page * page)319 void __cifs_readpage_to_fscache(struct inode *inode, struct page *page)
320 {
321 struct cifsInodeInfo *cifsi = CIFS_I(inode);
322 int ret;
323
324 cifs_dbg(FYI, "%s: (fsc: %p, p: %p, i: %p)\n",
325 __func__, cifsi->fscache, page, inode);
326 ret = fscache_write_page(cifsi->fscache, page,
327 cifsi->vfs_inode.i_size, GFP_KERNEL);
328 if (ret != 0)
329 fscache_uncache_page(cifsi->fscache, page);
330 }
331
__cifs_fscache_readpages_cancel(struct inode * inode,struct list_head * pages)332 void __cifs_fscache_readpages_cancel(struct inode *inode, struct list_head *pages)
333 {
334 cifs_dbg(FYI, "%s: (fsc: %p, i: %p)\n",
335 __func__, CIFS_I(inode)->fscache, inode);
336 fscache_readpages_cancel(CIFS_I(inode)->fscache, pages);
337 }
338
__cifs_fscache_invalidate_page(struct page * page,struct inode * inode)339 void __cifs_fscache_invalidate_page(struct page *page, struct inode *inode)
340 {
341 struct cifsInodeInfo *cifsi = CIFS_I(inode);
342 struct fscache_cookie *cookie = cifsi->fscache;
343
344 cifs_dbg(FYI, "%s: (0x%p/0x%p)\n", __func__, page, cookie);
345 fscache_wait_on_page_write(cookie, page);
346 fscache_uncache_page(cookie, page);
347 }
348