Merge git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched
[linux-2.6] / fs / 9p / v9fs.c
1 /*
2  *  linux/fs/9p/v9fs.c
3  *
4  *  This file contains functions assisting in mapping VFS to 9P2000
5  *
6  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
7  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License version 2
11  *  as published by the Free Software Foundation.
12  *
13  *  This program is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License
19  *  along with this program; if not, write to:
20  *  Free Software Foundation
21  *  51 Franklin Street, Fifth Floor
22  *  Boston, MA  02111-1301  USA
23  *
24  */
25
26 #include <linux/module.h>
27 #include <linux/errno.h>
28 #include <linux/fs.h>
29 #include <linux/sched.h>
30 #include <linux/parser.h>
31 #include <linux/idr.h>
32 #include <net/9p/9p.h>
33 #include <net/9p/transport.h>
34 #include <net/9p/conn.h>
35 #include <net/9p/client.h>
36 #include "v9fs.h"
37 #include "v9fs_vfs.h"
38
39 /*
40   * Option Parsing (code inspired by NFS code)
41   *
42   */
43
44 enum {
45         /* Options that take integer arguments */
46         Opt_debug, Opt_port, Opt_msize, Opt_uid, Opt_gid, Opt_afid,
47         Opt_rfdno, Opt_wfdno,
48         /* String options */
49         Opt_uname, Opt_remotename,
50         /* Options that take no arguments */
51         Opt_legacy, Opt_nodevmap, Opt_unix, Opt_tcp, Opt_fd, Opt_pci,
52         /* Cache options */
53         Opt_cache_loose,
54         /* Error token */
55         Opt_err
56 };
57
58 static match_table_t tokens = {
59         {Opt_debug, "debug=%x"},
60         {Opt_port, "port=%u"},
61         {Opt_msize, "msize=%u"},
62         {Opt_uid, "uid=%u"},
63         {Opt_gid, "gid=%u"},
64         {Opt_afid, "afid=%u"},
65         {Opt_rfdno, "rfdno=%u"},
66         {Opt_wfdno, "wfdno=%u"},
67         {Opt_uname, "uname=%s"},
68         {Opt_remotename, "aname=%s"},
69         {Opt_unix, "proto=unix"},
70         {Opt_tcp, "proto=tcp"},
71         {Opt_fd, "proto=fd"},
72 #ifdef CONFIG_PCI_9P
73         {Opt_pci, "proto=pci"},
74 #endif
75         {Opt_tcp, "tcp"},
76         {Opt_unix, "unix"},
77         {Opt_fd, "fd"},
78         {Opt_legacy, "noextend"},
79         {Opt_nodevmap, "nodevmap"},
80         {Opt_cache_loose, "cache=loose"},
81         {Opt_cache_loose, "loose"},
82         {Opt_err, NULL}
83 };
84
85 extern struct p9_transport *p9pci_trans_create(void);
86
87 /*
88  *  Parse option string.
89  */
90
91 /**
92  * v9fs_parse_options - parse mount options into session structure
93  * @options: options string passed from mount
94  * @v9ses: existing v9fs session information
95  *
96  */
97
98 static void v9fs_parse_options(char *options, struct v9fs_session_info *v9ses)
99 {
100         char *p;
101         substring_t args[MAX_OPT_ARGS];
102         int option;
103         int ret;
104
105         /* setup defaults */
106         v9ses->port = V9FS_PORT;
107         v9ses->maxdata = 9000;
108         v9ses->proto = PROTO_TCP;
109         v9ses->extended = 1;
110         v9ses->afid = ~0;
111         v9ses->debug = 0;
112         v9ses->rfdno = ~0;
113         v9ses->wfdno = ~0;
114         v9ses->cache = 0;
115
116         if (!options)
117                 return;
118
119         while ((p = strsep(&options, ",")) != NULL) {
120                 int token;
121                 if (!*p)
122                         continue;
123                 token = match_token(p, tokens, args);
124                 if (token < Opt_uname) {
125                         if ((ret = match_int(&args[0], &option)) < 0) {
126                                 P9_DPRINTK(P9_DEBUG_ERROR,
127                                         "integer field, but no integer?\n");
128                                 continue;
129                         }
130                 }
131                 switch (token) {
132                 case Opt_debug:
133                         v9ses->debug = option;
134 #ifdef CONFIG_NET_9P_DEBUG
135                         p9_debug_level = option;
136 #endif
137                         break;
138                 case Opt_port:
139                         v9ses->port = option;
140                         break;
141                 case Opt_msize:
142                         v9ses->maxdata = option;
143                         break;
144                 case Opt_uid:
145                         v9ses->uid = option;
146                         break;
147                 case Opt_gid:
148                         v9ses->gid = option;
149                         break;
150                 case Opt_afid:
151                         v9ses->afid = option;
152                         break;
153                 case Opt_rfdno:
154                         v9ses->rfdno = option;
155                         break;
156                 case Opt_wfdno:
157                         v9ses->wfdno = option;
158                         break;
159                 case Opt_tcp:
160                         v9ses->proto = PROTO_TCP;
161                         break;
162                 case Opt_unix:
163                         v9ses->proto = PROTO_UNIX;
164                         break;
165                 case Opt_pci:
166                         v9ses->proto = PROTO_PCI;
167                         break;
168                 case Opt_fd:
169                         v9ses->proto = PROTO_FD;
170                         break;
171                 case Opt_uname:
172                         match_strcpy(v9ses->name, &args[0]);
173                         break;
174                 case Opt_remotename:
175                         match_strcpy(v9ses->remotename, &args[0]);
176                         break;
177                 case Opt_legacy:
178                         v9ses->extended = 0;
179                         break;
180                 case Opt_nodevmap:
181                         v9ses->nodev = 1;
182                         break;
183                 case Opt_cache_loose:
184                         v9ses->cache = CACHE_LOOSE;
185                         break;
186                 default:
187                         continue;
188                 }
189         }
190 }
191
192 /**
193  * v9fs_session_init - initialize session
194  * @v9ses: session information structure
195  * @dev_name: device being mounted
196  * @data: options
197  *
198  */
199
200 struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
201                   const char *dev_name, char *data)
202 {
203         int retval = -EINVAL;
204         struct p9_transport *trans;
205         struct p9_fid *fid;
206
207         v9ses->name = __getname();
208         if (!v9ses->name)
209                 return ERR_PTR(-ENOMEM);
210
211         v9ses->remotename = __getname();
212         if (!v9ses->remotename) {
213                 __putname(v9ses->name);
214                 return ERR_PTR(-ENOMEM);
215         }
216
217         strcpy(v9ses->name, V9FS_DEFUSER);
218         strcpy(v9ses->remotename, V9FS_DEFANAME);
219
220         v9fs_parse_options(data, v9ses);
221
222         switch (v9ses->proto) {
223         case PROTO_TCP:
224                 trans = p9_trans_create_tcp(dev_name, v9ses->port);
225                 break;
226         case PROTO_UNIX:
227                 trans = p9_trans_create_unix(dev_name);
228                 *v9ses->remotename = 0;
229                 break;
230         case PROTO_FD:
231                 trans = p9_trans_create_fd(v9ses->rfdno, v9ses->wfdno);
232                 *v9ses->remotename = 0;
233                 break;
234 #ifdef CONFIG_PCI_9P
235         case PROTO_PCI:
236                 trans = p9pci_trans_create();
237                 *v9ses->remotename = 0;
238                 break;
239 #endif
240         default:
241                 printk(KERN_ERR "v9fs: Bad mount protocol %d\n", v9ses->proto);
242                 retval = -ENOPROTOOPT;
243                 goto error;
244         };
245
246         if (IS_ERR(trans)) {
247                 retval = PTR_ERR(trans);
248                 trans = NULL;
249                 goto error;
250         }
251
252         v9ses->clnt = p9_client_create(trans, v9ses->maxdata + P9_IOHDRSZ,
253                 v9ses->extended);
254
255         if (IS_ERR(v9ses->clnt)) {
256                 retval = PTR_ERR(v9ses->clnt);
257                 v9ses->clnt = NULL;
258                 P9_DPRINTK(P9_DEBUG_ERROR, "problem initializing 9p client\n");
259                 goto error;
260         }
261
262         fid = p9_client_attach(v9ses->clnt, NULL, v9ses->name,
263                                                         v9ses->remotename);
264         if (IS_ERR(fid)) {
265                 retval = PTR_ERR(fid);
266                 fid = NULL;
267                 P9_DPRINTK(P9_DEBUG_ERROR, "cannot attach\n");
268                 goto error;
269         }
270
271         return fid;
272
273 error:
274         v9fs_session_close(v9ses);
275         return ERR_PTR(retval);
276 }
277
278 /**
279  * v9fs_session_close - shutdown a session
280  * @v9ses: session information structure
281  *
282  */
283
284 void v9fs_session_close(struct v9fs_session_info *v9ses)
285 {
286         if (v9ses->clnt) {
287                 p9_client_destroy(v9ses->clnt);
288                 v9ses->clnt = NULL;
289         }
290
291         __putname(v9ses->name);
292         __putname(v9ses->remotename);
293 }
294
295 /**
296  * v9fs_session_cancel - mark transport as disconnected
297  *      and cancel all pending requests.
298  */
299 void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
300         P9_DPRINTK(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
301         p9_client_disconnect(v9ses->clnt);
302 }
303
304 extern int v9fs_error_init(void);
305
306 /**
307  * v9fs_init - Initialize module
308  *
309  */
310
311 static int __init init_v9fs(void)
312 {
313         printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
314
315         return register_filesystem(&v9fs_fs_type);
316 }
317
318 /**
319  * v9fs_init - shutdown module
320  *
321  */
322
323 static void __exit exit_v9fs(void)
324 {
325         unregister_filesystem(&v9fs_fs_type);
326 }
327
328 module_init(init_v9fs)
329 module_exit(exit_v9fs)
330
331 MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
332 MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
333 MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
334 MODULE_LICENSE("GPL");