Commit | Line | Data |
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9e82cf6a EVH |
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 as published by | |
11 | * the Free Software Foundation; either version 2 of the License, or | |
12 | * (at your option) any later version. | |
13 | * | |
14 | * This program is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | * GNU General Public License for more details. | |
18 | * | |
19 | * You should have received a copy of the GNU General Public License | |
20 | * along with this program; if not, write to: | |
21 | * Free Software Foundation | |
22 | * 51 Franklin Street, Fifth Floor | |
23 | * Boston, MA 02111-1301 USA | |
24 | * | |
25 | */ | |
26 | ||
27 | #include <linux/config.h> | |
28 | #include <linux/module.h> | |
29 | #include <linux/errno.h> | |
30 | #include <linux/fs.h> | |
31 | #include <linux/parser.h> | |
32 | #include <linux/idr.h> | |
33 | ||
34 | #include "debug.h" | |
35 | #include "v9fs.h" | |
36 | #include "9p.h" | |
37 | #include "v9fs_vfs.h" | |
38 | #include "transport.h" | |
39 | #include "mux.h" | |
9e82cf6a EVH |
40 | |
41 | /* TODO: sysfs or debugfs interface */ | |
42 | int v9fs_debug_level = 0; /* feature-rific global debug level */ | |
43 | ||
44 | /* | |
45 | * Option Parsing (code inspired by NFS code) | |
46 | * | |
47 | */ | |
48 | ||
49 | enum { | |
50 | /* Options that take integer arguments */ | |
51 | Opt_port, Opt_msize, Opt_uid, Opt_gid, Opt_afid, Opt_debug, | |
52 | Opt_rfdno, Opt_wfdno, | |
53 | /* String options */ | |
54 | Opt_name, Opt_remotename, | |
55 | /* Options that take no arguments */ | |
56 | Opt_legacy, Opt_nodevmap, Opt_unix, Opt_tcp, Opt_fd, | |
57 | /* Error token */ | |
58 | Opt_err | |
59 | }; | |
60 | ||
61 | static match_table_t tokens = { | |
62 | {Opt_port, "port=%u"}, | |
63 | {Opt_msize, "msize=%u"}, | |
64 | {Opt_uid, "uid=%u"}, | |
65 | {Opt_gid, "gid=%u"}, | |
66 | {Opt_afid, "afid=%u"}, | |
67 | {Opt_rfdno, "rfdno=%u"}, | |
68 | {Opt_wfdno, "wfdno=%u"}, | |
69 | {Opt_debug, "debug=%u"}, | |
70 | {Opt_name, "name=%s"}, | |
71 | {Opt_remotename, "aname=%s"}, | |
72 | {Opt_unix, "proto=unix"}, | |
73 | {Opt_tcp, "proto=tcp"}, | |
74 | {Opt_fd, "proto=fd"}, | |
75 | {Opt_tcp, "tcp"}, | |
76 | {Opt_unix, "unix"}, | |
77 | {Opt_fd, "fd"}, | |
78 | {Opt_legacy, "noextend"}, | |
79 | {Opt_nodevmap, "nodevmap"}, | |
80 | {Opt_err, NULL} | |
81 | }; | |
82 | ||
83 | /* | |
84 | * Parse option string. | |
85 | */ | |
86 | ||
87 | /** | |
88 | * v9fs_parse_options - parse mount options into session structure | |
89 | * @options: options string passed from mount | |
90 | * @v9ses: existing v9fs session information | |
91 | * | |
92 | */ | |
93 | ||
94 | static void v9fs_parse_options(char *options, struct v9fs_session_info *v9ses) | |
95 | { | |
96 | char *p; | |
97 | substring_t args[MAX_OPT_ARGS]; | |
98 | int option; | |
99 | int ret; | |
100 | ||
101 | /* setup defaults */ | |
102 | v9ses->port = V9FS_PORT; | |
103 | v9ses->maxdata = 9000; | |
104 | v9ses->proto = PROTO_TCP; | |
105 | v9ses->extended = 1; | |
106 | v9ses->afid = ~0; | |
107 | v9ses->debug = 0; | |
108 | v9ses->rfdno = ~0; | |
109 | v9ses->wfdno = ~0; | |
110 | ||
111 | if (!options) | |
112 | return; | |
113 | ||
114 | while ((p = strsep(&options, ",")) != NULL) { | |
115 | int token; | |
116 | if (!*p) | |
117 | continue; | |
118 | token = match_token(p, tokens, args); | |
119 | if (token < Opt_name) { | |
120 | if ((ret = match_int(&args[0], &option)) < 0) { | |
121 | dprintk(DEBUG_ERROR, | |
122 | "integer field, but no integer?\n"); | |
123 | continue; | |
124 | } | |
125 | ||
126 | } | |
127 | switch (token) { | |
128 | case Opt_port: | |
129 | v9ses->port = option; | |
130 | break; | |
131 | case Opt_msize: | |
132 | v9ses->maxdata = option; | |
133 | break; | |
134 | case Opt_uid: | |
135 | v9ses->uid = option; | |
136 | break; | |
137 | case Opt_gid: | |
138 | v9ses->gid = option; | |
139 | break; | |
140 | case Opt_afid: | |
141 | v9ses->afid = option; | |
142 | break; | |
143 | case Opt_rfdno: | |
144 | v9ses->rfdno = option; | |
145 | break; | |
146 | case Opt_wfdno: | |
147 | v9ses->wfdno = option; | |
148 | break; | |
149 | case Opt_debug: | |
150 | v9ses->debug = option; | |
151 | break; | |
152 | case Opt_tcp: | |
153 | v9ses->proto = PROTO_TCP; | |
154 | break; | |
155 | case Opt_unix: | |
156 | v9ses->proto = PROTO_UNIX; | |
157 | break; | |
158 | case Opt_fd: | |
159 | v9ses->proto = PROTO_FD; | |
160 | break; | |
161 | case Opt_name: | |
162 | match_strcpy(v9ses->name, &args[0]); | |
163 | break; | |
164 | case Opt_remotename: | |
165 | match_strcpy(v9ses->remotename, &args[0]); | |
166 | break; | |
167 | case Opt_legacy: | |
168 | v9ses->extended = 0; | |
169 | break; | |
170 | case Opt_nodevmap: | |
171 | v9ses->nodev = 1; | |
172 | break; | |
173 | default: | |
174 | continue; | |
175 | } | |
176 | } | |
177 | } | |
178 | ||
179 | /** | |
180 | * v9fs_inode2v9ses - safely extract v9fs session info from super block | |
181 | * @inode: inode to extract information from | |
182 | * | |
183 | * Paranoid function to extract v9ses information from superblock, | |
184 | * if anything is missing it will report an error. | |
185 | * | |
186 | */ | |
187 | ||
188 | struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) | |
189 | { | |
190 | return (inode->i_sb->s_fs_info); | |
191 | } | |
192 | ||
193 | /** | |
194 | * v9fs_get_idpool - allocate numeric id from pool | |
195 | * @p - pool to allocate from | |
196 | * | |
197 | * XXX - This seems to be an awful generic function, should it be in idr.c with | |
198 | * the lock included in struct idr? | |
199 | */ | |
200 | ||
201 | int v9fs_get_idpool(struct v9fs_idpool *p) | |
202 | { | |
203 | int i = 0; | |
204 | int error; | |
205 | ||
206 | retry: | |
207 | if (idr_pre_get(&p->pool, GFP_KERNEL) == 0) | |
208 | return 0; | |
209 | ||
210 | if (down_interruptible(&p->lock) == -EINTR) { | |
211 | eprintk(KERN_WARNING, "Interrupted while locking\n"); | |
212 | return -1; | |
213 | } | |
214 | ||
3cf6429a LI |
215 | /* no need to store exactly p, we just need something non-null */ |
216 | error = idr_get_new(&p->pool, p, &i); | |
9e82cf6a EVH |
217 | up(&p->lock); |
218 | ||
219 | if (error == -EAGAIN) | |
220 | goto retry; | |
221 | else if (error) | |
222 | return -1; | |
223 | ||
224 | return i; | |
225 | } | |
226 | ||
227 | /** | |
228 | * v9fs_put_idpool - release numeric id from pool | |
229 | * @p - pool to allocate from | |
230 | * | |
231 | * XXX - This seems to be an awful generic function, should it be in idr.c with | |
232 | * the lock included in struct idr? | |
233 | */ | |
234 | ||
235 | void v9fs_put_idpool(int id, struct v9fs_idpool *p) | |
236 | { | |
237 | if (down_interruptible(&p->lock) == -EINTR) { | |
238 | eprintk(KERN_WARNING, "Interrupted while locking\n"); | |
239 | return; | |
240 | } | |
241 | idr_remove(&p->pool, id); | |
242 | up(&p->lock); | |
243 | } | |
244 | ||
3cf6429a LI |
245 | /** |
246 | * v9fs_check_idpool - check if the specified id is available | |
247 | * @id - id to check | |
248 | * @p - pool | |
249 | */ | |
250 | int v9fs_check_idpool(int id, struct v9fs_idpool *p) | |
251 | { | |
252 | return idr_find(&p->pool, id) != NULL; | |
253 | } | |
254 | ||
9e82cf6a EVH |
255 | /** |
256 | * v9fs_session_init - initialize session | |
257 | * @v9ses: session information structure | |
258 | * @dev_name: device being mounted | |
259 | * @data: options | |
260 | * | |
261 | */ | |
262 | ||
263 | int | |
264 | v9fs_session_init(struct v9fs_session_info *v9ses, | |
265 | const char *dev_name, char *data) | |
266 | { | |
267 | struct v9fs_fcall *fcall = NULL; | |
268 | struct v9fs_transport *trans_proto; | |
269 | int n = 0; | |
270 | int newfid = -1; | |
271 | int retval = -EINVAL; | |
1dac06b2 | 272 | struct v9fs_str *version; |
9e82cf6a EVH |
273 | |
274 | v9ses->name = __getname(); | |
275 | if (!v9ses->name) | |
276 | return -ENOMEM; | |
277 | ||
278 | v9ses->remotename = __getname(); | |
279 | if (!v9ses->remotename) { | |
ce44eeb6 | 280 | __putname(v9ses->name); |
9e82cf6a EVH |
281 | return -ENOMEM; |
282 | } | |
283 | ||
284 | strcpy(v9ses->name, V9FS_DEFUSER); | |
285 | strcpy(v9ses->remotename, V9FS_DEFANAME); | |
286 | ||
287 | v9fs_parse_options(data, v9ses); | |
288 | ||
289 | /* set global debug level */ | |
290 | v9fs_debug_level = v9ses->debug; | |
291 | ||
292 | /* id pools that are session-dependent: FIDs and TIDs */ | |
293 | idr_init(&v9ses->fidpool.pool); | |
294 | init_MUTEX(&v9ses->fidpool.lock); | |
9e82cf6a EVH |
295 | |
296 | switch (v9ses->proto) { | |
297 | case PROTO_TCP: | |
298 | trans_proto = &v9fs_trans_tcp; | |
299 | break; | |
300 | case PROTO_UNIX: | |
301 | trans_proto = &v9fs_trans_unix; | |
302 | *v9ses->remotename = 0; | |
303 | break; | |
304 | case PROTO_FD: | |
305 | trans_proto = &v9fs_trans_fd; | |
306 | *v9ses->remotename = 0; | |
9e82cf6a EVH |
307 | break; |
308 | default: | |
309 | printk(KERN_ERR "v9fs: Bad mount protocol %d\n", v9ses->proto); | |
310 | retval = -ENOPROTOOPT; | |
311 | goto SessCleanUp; | |
312 | }; | |
313 | ||
a8e63bff LI |
314 | v9ses->transport = kmalloc(sizeof(*v9ses->transport), GFP_KERNEL); |
315 | if (!v9ses->transport) { | |
316 | retval = -ENOMEM; | |
317 | goto SessCleanUp; | |
318 | } | |
319 | ||
320 | memmove(v9ses->transport, trans_proto, sizeof(*v9ses->transport)); | |
9e82cf6a EVH |
321 | |
322 | if ((retval = v9ses->transport->init(v9ses, dev_name, data)) < 0) { | |
323 | eprintk(KERN_ERR, "problem initializing transport\n"); | |
324 | goto SessCleanUp; | |
325 | } | |
326 | ||
327 | v9ses->inprogress = 0; | |
328 | v9ses->shutdown = 0; | |
329 | v9ses->session_hung = 0; | |
330 | ||
3cf6429a LI |
331 | v9ses->mux = v9fs_mux_init(v9ses->transport, v9ses->maxdata + V9FS_IOHDRSZ, |
332 | &v9ses->extended); | |
333 | ||
334 | if (IS_ERR(v9ses->mux)) { | |
335 | retval = PTR_ERR(v9ses->mux); | |
336 | v9ses->mux = NULL; | |
9e82cf6a EVH |
337 | dprintk(DEBUG_ERROR, "problem initializing mux\n"); |
338 | goto SessCleanUp; | |
339 | } | |
340 | ||
341 | if (v9ses->afid == ~0) { | |
342 | if (v9ses->extended) | |
343 | retval = | |
344 | v9fs_t_version(v9ses, v9ses->maxdata, "9P2000.u", | |
345 | &fcall); | |
346 | else | |
347 | retval = v9fs_t_version(v9ses, v9ses->maxdata, "9P2000", | |
348 | &fcall); | |
349 | ||
350 | if (retval < 0) { | |
351 | dprintk(DEBUG_ERROR, "v9fs_t_version failed\n"); | |
352 | goto FreeFcall; | |
353 | } | |
354 | ||
1dac06b2 LI |
355 | version = &fcall->params.rversion.version; |
356 | if (version->len==8 && !memcmp(version->str, "9P2000.u", 8)) { | |
9e82cf6a EVH |
357 | dprintk(DEBUG_9P, "9P2000 UNIX extensions enabled\n"); |
358 | v9ses->extended = 1; | |
1dac06b2 | 359 | } else if (version->len==6 && !memcmp(version->str, "9P2000", 6)) { |
9e82cf6a EVH |
360 | dprintk(DEBUG_9P, "9P2000 legacy mode enabled\n"); |
361 | v9ses->extended = 0; | |
1dac06b2 LI |
362 | } else { |
363 | retval = -EREMOTEIO; | |
364 | goto FreeFcall; | |
9e82cf6a EVH |
365 | } |
366 | ||
367 | n = fcall->params.rversion.msize; | |
368 | kfree(fcall); | |
369 | ||
370 | if (n < v9ses->maxdata) | |
371 | v9ses->maxdata = n; | |
372 | } | |
373 | ||
374 | newfid = v9fs_get_idpool(&v9ses->fidpool); | |
375 | if (newfid < 0) { | |
376 | eprintk(KERN_WARNING, "couldn't allocate FID\n"); | |
377 | retval = -ENOMEM; | |
378 | goto SessCleanUp; | |
379 | } | |
380 | /* it is a little bit ugly, but we have to prevent newfid */ | |
381 | /* being the same as afid, so if it is, get a new fid */ | |
382 | if (v9ses->afid != ~0 && newfid == v9ses->afid) { | |
383 | newfid = v9fs_get_idpool(&v9ses->fidpool); | |
384 | if (newfid < 0) { | |
385 | eprintk(KERN_WARNING, "couldn't allocate FID\n"); | |
386 | retval = -ENOMEM; | |
387 | goto SessCleanUp; | |
388 | } | |
389 | } | |
390 | ||
391 | if ((retval = | |
392 | v9fs_t_attach(v9ses, v9ses->name, v9ses->remotename, newfid, | |
393 | v9ses->afid, NULL)) | |
394 | < 0) { | |
395 | dprintk(DEBUG_ERROR, "cannot attach\n"); | |
396 | goto SessCleanUp; | |
397 | } | |
398 | ||
399 | if (v9ses->afid != ~0) { | |
3cf6429a | 400 | if (v9fs_t_clunk(v9ses, v9ses->afid)) |
9e82cf6a EVH |
401 | dprintk(DEBUG_ERROR, "clunk failed\n"); |
402 | } | |
403 | ||
404 | return newfid; | |
405 | ||
406 | FreeFcall: | |
407 | kfree(fcall); | |
408 | ||
409 | SessCleanUp: | |
410 | v9fs_session_close(v9ses); | |
411 | return retval; | |
412 | } | |
413 | ||
414 | /** | |
415 | * v9fs_session_close - shutdown a session | |
416 | * @v9ses: session information structure | |
417 | * | |
418 | */ | |
419 | ||
420 | void v9fs_session_close(struct v9fs_session_info *v9ses) | |
421 | { | |
3cf6429a LI |
422 | if (v9ses->mux) { |
423 | v9fs_mux_destroy(v9ses->mux); | |
424 | v9ses->mux = NULL; | |
9e82cf6a EVH |
425 | } |
426 | ||
3cf6429a | 427 | if (v9ses->transport) { |
9e82cf6a | 428 | v9ses->transport->close(v9ses->transport); |
3cf6429a LI |
429 | kfree(v9ses->transport); |
430 | v9ses->transport = NULL; | |
431 | } | |
9e82cf6a | 432 | |
ce44eeb6 DA |
433 | __putname(v9ses->name); |
434 | __putname(v9ses->remotename); | |
9e82cf6a EVH |
435 | } |
436 | ||
322b329a EVH |
437 | /** |
438 | * v9fs_session_cancel - mark transport as disconnected | |
439 | * and cancel all pending requests. | |
440 | */ | |
441 | void v9fs_session_cancel(struct v9fs_session_info *v9ses) { | |
3cf6429a | 442 | dprintk(DEBUG_ERROR, "cancel session %p\n", v9ses); |
322b329a | 443 | v9ses->transport->status = Disconnected; |
3cf6429a | 444 | v9fs_mux_cancel(v9ses->mux, -EIO); |
322b329a EVH |
445 | } |
446 | ||
9e82cf6a EVH |
447 | extern int v9fs_error_init(void); |
448 | ||
449 | /** | |
450 | * v9fs_init - Initialize module | |
451 | * | |
452 | */ | |
453 | ||
454 | static int __init init_v9fs(void) | |
455 | { | |
1dac06b2 LI |
456 | int ret; |
457 | ||
9e82cf6a EVH |
458 | v9fs_error_init(); |
459 | ||
460 | printk(KERN_INFO "Installing v9fs 9P2000 file system support\n"); | |
461 | ||
1dac06b2 LI |
462 | ret = v9fs_mux_global_init(); |
463 | if (!ret) | |
464 | ret = register_filesystem(&v9fs_fs_type); | |
465 | ||
466 | return ret; | |
9e82cf6a EVH |
467 | } |
468 | ||
469 | /** | |
470 | * v9fs_init - shutdown module | |
471 | * | |
472 | */ | |
473 | ||
474 | static void __exit exit_v9fs(void) | |
475 | { | |
3cf6429a | 476 | v9fs_mux_global_exit(); |
9e82cf6a EVH |
477 | unregister_filesystem(&v9fs_fs_type); |
478 | } | |
479 | ||
480 | module_init(init_v9fs) | |
481 | module_exit(exit_v9fs) | |
482 | ||
483 | MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>"); | |
484 | MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>"); | |
485 | MODULE_LICENSE("GPL"); |