]>
git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - fs/9p/v9fs.c
4 * This file contains functions assisting in mapping VFS to 9P2000
6 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
7 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
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.
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.
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
27 #include <linux/config.h>
28 #include <linux/module.h>
29 #include <linux/errno.h>
31 #include <linux/parser.h>
32 #include <linux/idr.h>
38 #include "transport.h"
41 /* TODO: sysfs or debugfs interface */
42 int v9fs_debug_level
= 0; /* feature-rific global debug level */
45 * Option Parsing (code inspired by NFS code)
50 /* Options that take integer arguments */
51 Opt_port
, Opt_msize
, Opt_uid
, Opt_gid
, Opt_afid
, Opt_debug
,
54 Opt_name
, Opt_remotename
,
55 /* Options that take no arguments */
56 Opt_legacy
, Opt_nodevmap
, Opt_unix
, Opt_tcp
, Opt_fd
,
61 static match_table_t tokens
= {
62 {Opt_port
, "port=%u"},
63 {Opt_msize
, "msize=%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"},
78 {Opt_legacy
, "noextend"},
79 {Opt_nodevmap
, "nodevmap"},
84 * Parse option string.
88 * v9fs_parse_options - parse mount options into session structure
89 * @options: options string passed from mount
90 * @v9ses: existing v9fs session information
94 static void v9fs_parse_options(char *options
, struct v9fs_session_info
*v9ses
)
97 substring_t args
[MAX_OPT_ARGS
];
102 v9ses
->port
= V9FS_PORT
;
103 v9ses
->maxdata
= 9000;
104 v9ses
->proto
= PROTO_TCP
;
114 while ((p
= strsep(&options
, ",")) != NULL
) {
118 token
= match_token(p
, tokens
, args
);
119 if (token
< Opt_name
) {
120 if ((ret
= match_int(&args
[0], &option
)) < 0) {
122 "integer field, but no integer?\n");
129 v9ses
->port
= option
;
132 v9ses
->maxdata
= option
;
141 v9ses
->afid
= option
;
144 v9ses
->rfdno
= option
;
147 v9ses
->wfdno
= option
;
150 v9ses
->debug
= option
;
153 v9ses
->proto
= PROTO_TCP
;
156 v9ses
->proto
= PROTO_UNIX
;
159 v9ses
->proto
= PROTO_FD
;
162 match_strcpy(v9ses
->name
, &args
[0]);
165 match_strcpy(v9ses
->remotename
, &args
[0]);
180 * v9fs_inode2v9ses - safely extract v9fs session info from super block
181 * @inode: inode to extract information from
183 * Paranoid function to extract v9ses information from superblock,
184 * if anything is missing it will report an error.
188 struct v9fs_session_info
*v9fs_inode2v9ses(struct inode
*inode
)
190 return (inode
->i_sb
->s_fs_info
);
194 * v9fs_get_idpool - allocate numeric id from pool
195 * @p - pool to allocate from
197 * XXX - This seems to be an awful generic function, should it be in idr.c with
198 * the lock included in struct idr?
201 int v9fs_get_idpool(struct v9fs_idpool
*p
)
207 if (idr_pre_get(&p
->pool
, GFP_KERNEL
) == 0)
210 if (down_interruptible(&p
->lock
) == -EINTR
) {
211 eprintk(KERN_WARNING
, "Interrupted while locking\n");
215 /* no need to store exactly p, we just need something non-null */
216 error
= idr_get_new(&p
->pool
, p
, &i
);
219 if (error
== -EAGAIN
)
228 * v9fs_put_idpool - release numeric id from pool
229 * @p - pool to allocate from
231 * XXX - This seems to be an awful generic function, should it be in idr.c with
232 * the lock included in struct idr?
235 void v9fs_put_idpool(int id
, struct v9fs_idpool
*p
)
237 if (down_interruptible(&p
->lock
) == -EINTR
) {
238 eprintk(KERN_WARNING
, "Interrupted while locking\n");
241 idr_remove(&p
->pool
, id
);
246 * v9fs_check_idpool - check if the specified id is available
250 int v9fs_check_idpool(int id
, struct v9fs_idpool
*p
)
252 return idr_find(&p
->pool
, id
) != NULL
;
256 * v9fs_session_init - initialize session
257 * @v9ses: session information structure
258 * @dev_name: device being mounted
264 v9fs_session_init(struct v9fs_session_info
*v9ses
,
265 const char *dev_name
, char *data
)
267 struct v9fs_fcall
*fcall
= NULL
;
268 struct v9fs_transport
*trans_proto
;
271 int retval
= -EINVAL
;
273 v9ses
->name
= __getname();
277 v9ses
->remotename
= __getname();
278 if (!v9ses
->remotename
) {
279 __putname(v9ses
->name
);
283 strcpy(v9ses
->name
, V9FS_DEFUSER
);
284 strcpy(v9ses
->remotename
, V9FS_DEFANAME
);
286 v9fs_parse_options(data
, v9ses
);
288 /* set global debug level */
289 v9fs_debug_level
= v9ses
->debug
;
291 /* id pools that are session-dependent: FIDs and TIDs */
292 idr_init(&v9ses
->fidpool
.pool
);
293 init_MUTEX(&v9ses
->fidpool
.lock
);
295 switch (v9ses
->proto
) {
297 trans_proto
= &v9fs_trans_tcp
;
300 trans_proto
= &v9fs_trans_unix
;
301 *v9ses
->remotename
= 0;
304 trans_proto
= &v9fs_trans_fd
;
305 *v9ses
->remotename
= 0;
308 printk(KERN_ERR
"v9fs: Bad mount protocol %d\n", v9ses
->proto
);
309 retval
= -ENOPROTOOPT
;
313 v9ses
->transport
= kmalloc(sizeof(*v9ses
->transport
), GFP_KERNEL
);
314 if (!v9ses
->transport
) {
319 memmove(v9ses
->transport
, trans_proto
, sizeof(*v9ses
->transport
));
321 if ((retval
= v9ses
->transport
->init(v9ses
, dev_name
, data
)) < 0) {
322 eprintk(KERN_ERR
, "problem initializing transport\n");
326 v9ses
->inprogress
= 0;
328 v9ses
->session_hung
= 0;
330 v9ses
->mux
= v9fs_mux_init(v9ses
->transport
, v9ses
->maxdata
+ V9FS_IOHDRSZ
,
333 if (IS_ERR(v9ses
->mux
)) {
334 retval
= PTR_ERR(v9ses
->mux
);
336 dprintk(DEBUG_ERROR
, "problem initializing mux\n");
340 if (v9ses
->afid
== ~0) {
343 v9fs_t_version(v9ses
, v9ses
->maxdata
, "9P2000.u",
346 retval
= v9fs_t_version(v9ses
, v9ses
->maxdata
, "9P2000",
350 dprintk(DEBUG_ERROR
, "v9fs_t_version failed\n");
354 /* Really should check for 9P1 and report error */
355 if (!v9fs_str_compare("9P2000.u", &fcall
->params
.rversion
.version
)) {
356 dprintk(DEBUG_9P
, "9P2000 UNIX extensions enabled\n");
359 dprintk(DEBUG_9P
, "9P2000 legacy mode enabled\n");
363 n
= fcall
->params
.rversion
.msize
;
366 if (n
< v9ses
->maxdata
)
370 newfid
= v9fs_get_idpool(&v9ses
->fidpool
);
372 eprintk(KERN_WARNING
, "couldn't allocate FID\n");
376 /* it is a little bit ugly, but we have to prevent newfid */
377 /* being the same as afid, so if it is, get a new fid */
378 if (v9ses
->afid
!= ~0 && newfid
== v9ses
->afid
) {
379 newfid
= v9fs_get_idpool(&v9ses
->fidpool
);
381 eprintk(KERN_WARNING
, "couldn't allocate FID\n");
388 v9fs_t_attach(v9ses
, v9ses
->name
, v9ses
->remotename
, newfid
,
391 dprintk(DEBUG_ERROR
, "cannot attach\n");
395 if (v9ses
->afid
!= ~0) {
396 if (v9fs_t_clunk(v9ses
, v9ses
->afid
))
397 dprintk(DEBUG_ERROR
, "clunk failed\n");
406 v9fs_session_close(v9ses
);
411 * v9fs_session_close - shutdown a session
412 * @v9ses: session information structure
416 void v9fs_session_close(struct v9fs_session_info
*v9ses
)
419 v9fs_mux_destroy(v9ses
->mux
);
423 if (v9ses
->transport
) {
424 v9ses
->transport
->close(v9ses
->transport
);
425 kfree(v9ses
->transport
);
426 v9ses
->transport
= NULL
;
429 __putname(v9ses
->name
);
430 __putname(v9ses
->remotename
);
434 * v9fs_session_cancel - mark transport as disconnected
435 * and cancel all pending requests.
437 void v9fs_session_cancel(struct v9fs_session_info
*v9ses
) {
438 dprintk(DEBUG_ERROR
, "cancel session %p\n", v9ses
);
439 v9ses
->transport
->status
= Disconnected
;
440 v9fs_mux_cancel(v9ses
->mux
, -EIO
);
443 extern int v9fs_error_init(void);
446 * v9fs_init - Initialize module
450 static int __init
init_v9fs(void)
454 printk(KERN_INFO
"Installing v9fs 9P2000 file system support\n");
456 v9fs_mux_global_init();
457 return register_filesystem(&v9fs_fs_type
);
461 * v9fs_init - shutdown module
465 static void __exit
exit_v9fs(void)
467 v9fs_mux_global_exit();
468 unregister_filesystem(&v9fs_fs_type
);
471 module_init(init_v9fs
)
472 module_exit(exit_v9fs
)
474 MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
475 MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
476 MODULE_LICENSE("GPL");