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
100 sharename = extract_sharename(tcon->treeName);
101 if (IS_ERR(sharename)) {
102 cifs_dbg(FYI, "%s: couldn't extract sharename\n", __func__);
103 tcon->fscache = NULL;
104 return;
105 }
106
107 tcon->fscache =
108 fscache_acquire_cookie(server->fscache,
109 &cifs_fscache_super_index_def,
110 sharename, strlen(sharename),
111 &tcon->resource_id, sizeof(tcon->resource_id),
112 tcon, 0, true);
113 kfree(sharename);
114 cifs_dbg(FYI, "%s: (0x%p/0x%p)\n",
115 __func__, server->fscache, tcon->fscache);
116 }
117
cifs_fscache_release_super_cookie(struct cifs_tcon * tcon)118 void cifs_fscache_release_super_cookie(struct cifs_tcon *tcon)
119 {
120 cifs_dbg(FYI, "%s: (0x%p)\n", __func__, tcon->fscache);
121 fscache_relinquish_cookie(tcon->fscache, &tcon->resource_id, false);
122 tcon->fscache = NULL;
123 }
124
cifs_fscache_acquire_inode_cookie(struct cifsInodeInfo * cifsi,struct cifs_tcon * tcon)125 static void cifs_fscache_acquire_inode_cookie(struct cifsInodeInfo *cifsi,
126 struct cifs_tcon *tcon)
127 {
128 struct cifs_fscache_inode_auxdata auxdata;
129
130 memset(&auxdata, 0, sizeof(auxdata));
131 auxdata.eof = cifsi->server_eof;
132 auxdata.last_write_time_sec = cifsi->vfs_inode.i_mtime.tv_sec;
133 auxdata.last_change_time_sec = cifsi->vfs_inode.i_ctime.tv_sec;
134 auxdata.last_write_time_nsec = cifsi->vfs_inode.i_mtime.tv_nsec;
135 auxdata.last_change_time_nsec = cifsi->vfs_inode.i_ctime.tv_nsec;
136
137 cifsi->fscache =
138 fscache_acquire_cookie(tcon->fscache,
139 &cifs_fscache_inode_object_def,
140 &cifsi->uniqueid, sizeof(cifsi->uniqueid),
141 &auxdata, sizeof(auxdata),
142 cifsi, cifsi->vfs_inode.i_size, true);
143 }
144
cifs_fscache_enable_inode_cookie(struct inode * inode)145 static void cifs_fscache_enable_inode_cookie(struct inode *inode)
146 {
147 struct cifsInodeInfo *cifsi = CIFS_I(inode);
148 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
149 struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
150
151 if (cifsi->fscache)
152 return;
153
154 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_FSCACHE))
155 return;
156
157 cifs_fscache_acquire_inode_cookie(cifsi, tcon);
158
159 cifs_dbg(FYI, "%s: got FH cookie (0x%p/0x%p)\n",
160 __func__, tcon->fscache, cifsi->fscache);
161 }
162
cifs_fscache_release_inode_cookie(struct inode * inode)163 void cifs_fscache_release_inode_cookie(struct inode *inode)
164 {
165 struct cifs_fscache_inode_auxdata auxdata;
166 struct cifsInodeInfo *cifsi = CIFS_I(inode);
167
168 if (cifsi->fscache) {
169 memset(&auxdata, 0, sizeof(auxdata));
170 auxdata.eof = cifsi->server_eof;
171 auxdata.last_write_time_sec = cifsi->vfs_inode.i_mtime.tv_sec;
172 auxdata.last_change_time_sec = cifsi->vfs_inode.i_ctime.tv_sec;
173 auxdata.last_write_time_nsec = cifsi->vfs_inode.i_mtime.tv_nsec;
174 auxdata.last_change_time_nsec = cifsi->vfs_inode.i_ctime.tv_nsec;
175
176 cifs_dbg(FYI, "%s: (0x%p)\n", __func__, cifsi->fscache);
177 fscache_relinquish_cookie(cifsi->fscache, &auxdata, false);
178 cifsi->fscache = NULL;
179 }
180 }
181
cifs_fscache_disable_inode_cookie(struct inode * inode)182 static void cifs_fscache_disable_inode_cookie(struct inode *inode)
183 {
184 struct cifsInodeInfo *cifsi = CIFS_I(inode);
185
186 if (cifsi->fscache) {
187 cifs_dbg(FYI, "%s: (0x%p)\n", __func__, cifsi->fscache);
188 fscache_uncache_all_inode_pages(cifsi->fscache, inode);
189 fscache_relinquish_cookie(cifsi->fscache, NULL, true);
190 cifsi->fscache = NULL;
191 }
192 }
193
cifs_fscache_set_inode_cookie(struct inode * inode,struct file * filp)194 void cifs_fscache_set_inode_cookie(struct inode *inode, struct file *filp)
195 {
196 if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
197 cifs_fscache_disable_inode_cookie(inode);
198 else
199 cifs_fscache_enable_inode_cookie(inode);
200 }
201
cifs_fscache_reset_inode_cookie(struct inode * inode)202 void cifs_fscache_reset_inode_cookie(struct inode *inode)
203 {
204 struct cifsInodeInfo *cifsi = CIFS_I(inode);
205 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
206 struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
207 struct fscache_cookie *old = cifsi->fscache;
208
209 if (cifsi->fscache) {
210 /* retire the current fscache cache and get a new one */
211 fscache_relinquish_cookie(cifsi->fscache, NULL, true);
212
213 cifs_fscache_acquire_inode_cookie(cifsi, tcon);
214 cifs_dbg(FYI, "%s: new cookie 0x%p oldcookie 0x%p\n",
215 __func__, cifsi->fscache, old);
216 }
217 }
218
cifs_fscache_release_page(struct page * page,gfp_t gfp)219 int cifs_fscache_release_page(struct page *page, gfp_t gfp)
220 {
221 if (PageFsCache(page)) {
222 struct inode *inode = page->mapping->host;
223 struct cifsInodeInfo *cifsi = CIFS_I(inode);
224
225 cifs_dbg(FYI, "%s: (0x%p/0x%p)\n",
226 __func__, page, cifsi->fscache);
227 if (!fscache_maybe_release_page(cifsi->fscache, page, gfp))
228 return 0;
229 }
230
231 return 1;
232 }
233
cifs_readpage_from_fscache_complete(struct page * page,void * ctx,int error)234 static void cifs_readpage_from_fscache_complete(struct page *page, void *ctx,
235 int error)
236 {
237 cifs_dbg(FYI, "%s: (0x%p/%d)\n", __func__, page, error);
238 if (!error)
239 SetPageUptodate(page);
240 unlock_page(page);
241 }
242
243 /*
244 * Retrieve a page from FS-Cache
245 */
__cifs_readpage_from_fscache(struct inode * inode,struct page * page)246 int __cifs_readpage_from_fscache(struct inode *inode, struct page *page)
247 {
248 int ret;
249
250 cifs_dbg(FYI, "%s: (fsc:%p, p:%p, i:0x%p\n",
251 __func__, CIFS_I(inode)->fscache, page, inode);
252 ret = fscache_read_or_alloc_page(CIFS_I(inode)->fscache, page,
253 cifs_readpage_from_fscache_complete,
254 NULL,
255 GFP_KERNEL);
256 switch (ret) {
257
258 case 0: /* page found in fscache, read submitted */
259 cifs_dbg(FYI, "%s: submitted\n", __func__);
260 return ret;
261 case -ENOBUFS: /* page won't be cached */
262 case -ENODATA: /* page not in cache */
263 cifs_dbg(FYI, "%s: %d\n", __func__, ret);
264 return 1;
265
266 default:
267 cifs_dbg(VFS, "unknown error ret = %d\n", ret);
268 }
269 return ret;
270 }
271
272 /*
273 * Retrieve a set of pages from FS-Cache
274 */
__cifs_readpages_from_fscache(struct inode * inode,struct address_space * mapping,struct list_head * pages,unsigned * nr_pages)275 int __cifs_readpages_from_fscache(struct inode *inode,
276 struct address_space *mapping,
277 struct list_head *pages,
278 unsigned *nr_pages)
279 {
280 int ret;
281
282 cifs_dbg(FYI, "%s: (0x%p/%u/0x%p)\n",
283 __func__, CIFS_I(inode)->fscache, *nr_pages, inode);
284 ret = fscache_read_or_alloc_pages(CIFS_I(inode)->fscache, mapping,
285 pages, nr_pages,
286 cifs_readpage_from_fscache_complete,
287 NULL,
288 mapping_gfp_mask(mapping));
289 switch (ret) {
290 case 0: /* read submitted to the cache for all pages */
291 cifs_dbg(FYI, "%s: submitted\n", __func__);
292 return ret;
293
294 case -ENOBUFS: /* some pages are not cached and can't be */
295 case -ENODATA: /* some pages are not cached */
296 cifs_dbg(FYI, "%s: no page\n", __func__);
297 return 1;
298
299 default:
300 cifs_dbg(FYI, "unknown error ret = %d\n", ret);
301 }
302
303 return ret;
304 }
305
__cifs_readpage_to_fscache(struct inode * inode,struct page * page)306 void __cifs_readpage_to_fscache(struct inode *inode, struct page *page)
307 {
308 struct cifsInodeInfo *cifsi = CIFS_I(inode);
309 int ret;
310
311 cifs_dbg(FYI, "%s: (fsc: %p, p: %p, i: %p)\n",
312 __func__, cifsi->fscache, page, inode);
313 ret = fscache_write_page(cifsi->fscache, page,
314 cifsi->vfs_inode.i_size, GFP_KERNEL);
315 if (ret != 0)
316 fscache_uncache_page(cifsi->fscache, page);
317 }
318
__cifs_fscache_readpages_cancel(struct inode * inode,struct list_head * pages)319 void __cifs_fscache_readpages_cancel(struct inode *inode, struct list_head *pages)
320 {
321 cifs_dbg(FYI, "%s: (fsc: %p, i: %p)\n",
322 __func__, CIFS_I(inode)->fscache, inode);
323 fscache_readpages_cancel(CIFS_I(inode)->fscache, pages);
324 }
325
__cifs_fscache_invalidate_page(struct page * page,struct inode * inode)326 void __cifs_fscache_invalidate_page(struct page *page, struct inode *inode)
327 {
328 struct cifsInodeInfo *cifsi = CIFS_I(inode);
329 struct fscache_cookie *cookie = cifsi->fscache;
330
331 cifs_dbg(FYI, "%s: (0x%p/0x%p)\n", __func__, page, cookie);
332 fscache_wait_on_page_write(cookie, page);
333 fscache_uncache_page(cookie, page);
334 }
335