4 * This file contains functions assisting in mapping VFS to 9P2000
6 * Copyright (C) 2004-2008 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 version 2
11 * as published by the Free Software Foundation.
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.
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
26 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
28 #include <linux/module.h>
29 #include <linux/errno.h>
31 #include <linux/sched.h>
32 #include <linux/parser.h>
33 #include <linux/idr.h>
34 #include <linux/slab.h>
35 #include <net/9p/9p.h>
36 #include <net/9p/client.h>
37 #include <net/9p/transport.h>
42 static DEFINE_SPINLOCK(v9fs_sessionlist_lock
);
43 static LIST_HEAD(v9fs_sessionlist
);
44 struct kmem_cache
*v9fs_inode_cache
;
47 * Option Parsing (code inspired by NFS code)
48 * NOTE: each transport will parse its own options
52 /* Options that take integer arguments */
53 Opt_debug
, Opt_dfltuid
, Opt_dfltgid
, Opt_afid
,
55 Opt_uname
, Opt_remotename
, Opt_cache
, Opt_cachetag
,
56 /* Options that take no arguments */
59 Opt_cache_loose
, Opt_fscache
, Opt_mmap
,
61 Opt_access
, Opt_posixacl
,
66 static const match_table_t tokens
= {
67 {Opt_debug
, "debug=%x"},
68 {Opt_dfltuid
, "dfltuid=%u"},
69 {Opt_dfltgid
, "dfltgid=%u"},
70 {Opt_afid
, "afid=%u"},
71 {Opt_uname
, "uname=%s"},
72 {Opt_remotename
, "aname=%s"},
73 {Opt_nodevmap
, "nodevmap"},
74 {Opt_cache
, "cache=%s"},
75 {Opt_cache_loose
, "loose"},
76 {Opt_fscache
, "fscache"},
78 {Opt_cachetag
, "cachetag=%s"},
79 {Opt_access
, "access=%s"},
80 {Opt_posixacl
, "posixacl"},
84 /* Interpret mount options for cache mode */
85 static int get_cache_mode(char *s
)
87 int version
= -EINVAL
;
89 if (!strcmp(s
, "loose")) {
90 version
= CACHE_LOOSE
;
91 p9_debug(P9_DEBUG_9P
, "Cache mode: loose\n");
92 } else if (!strcmp(s
, "fscache")) {
93 version
= CACHE_FSCACHE
;
94 p9_debug(P9_DEBUG_9P
, "Cache mode: fscache\n");
95 } else if (!strcmp(s
, "mmap")) {
97 p9_debug(P9_DEBUG_9P
, "Cache mode: mmap\n");
98 } else if (!strcmp(s
, "none")) {
100 p9_debug(P9_DEBUG_9P
, "Cache mode: none\n");
102 pr_info("Unknown Cache mode %s\n", s
);
107 * v9fs_parse_options - parse mount options into session structure
108 * @v9ses: existing v9fs session information
110 * Return 0 upon success, -ERRNO upon failure.
113 static int v9fs_parse_options(struct v9fs_session_info
*v9ses
, char *opts
)
115 char *options
, *tmp_options
;
116 substring_t args
[MAX_OPT_ARGS
];
125 v9ses
->cache
= CACHE_NONE
;
126 #ifdef CONFIG_9P_FSCACHE
127 v9ses
->cachetag
= NULL
;
133 tmp_options
= kstrdup(opts
, GFP_KERNEL
);
136 goto fail_option_alloc
;
138 options
= tmp_options
;
140 while ((p
= strsep(&options
, ",")) != NULL
) {
144 token
= match_token(p
, tokens
, args
);
147 r
= match_int(&args
[0], &option
);
149 p9_debug(P9_DEBUG_ERROR
,
150 "integer field, but no integer?\n");
154 v9ses
->debug
= option
;
155 #ifdef CONFIG_NET_9P_DEBUG
156 p9_debug_level
= option
;
161 r
= match_int(&args
[0], &option
);
163 p9_debug(P9_DEBUG_ERROR
,
164 "integer field, but no integer?\n");
168 v9ses
->dfltuid
= make_kuid(current_user_ns(), option
);
169 if (!uid_valid(v9ses
->dfltuid
)) {
170 p9_debug(P9_DEBUG_ERROR
,
171 "uid field, but not a uid?\n");
177 r
= match_int(&args
[0], &option
);
179 p9_debug(P9_DEBUG_ERROR
,
180 "integer field, but no integer?\n");
184 v9ses
->dfltgid
= make_kgid(current_user_ns(), option
);
185 if (!gid_valid(v9ses
->dfltgid
)) {
186 p9_debug(P9_DEBUG_ERROR
,
187 "gid field, but not a gid?\n");
193 r
= match_int(&args
[0], &option
);
195 p9_debug(P9_DEBUG_ERROR
,
196 "integer field, but no integer?\n");
200 v9ses
->afid
= option
;
204 v9ses
->uname
= match_strdup(&args
[0]);
207 goto free_and_return
;
212 v9ses
->aname
= match_strdup(&args
[0]);
215 goto free_and_return
;
221 case Opt_cache_loose
:
222 v9ses
->cache
= CACHE_LOOSE
;
225 v9ses
->cache
= CACHE_FSCACHE
;
228 v9ses
->cache
= CACHE_MMAP
;
231 #ifdef CONFIG_9P_FSCACHE
232 v9ses
->cachetag
= match_strdup(&args
[0]);
236 s
= match_strdup(&args
[0]);
239 p9_debug(P9_DEBUG_ERROR
,
240 "problem allocating copy of cache arg\n");
241 goto free_and_return
;
243 ret
= get_cache_mode(s
);
244 if (ret
== -EINVAL
) {
246 goto free_and_return
;
254 s
= match_strdup(&args
[0]);
257 p9_debug(P9_DEBUG_ERROR
,
258 "problem allocating copy of access arg\n");
259 goto free_and_return
;
262 v9ses
->flags
&= ~V9FS_ACCESS_MASK
;
263 if (strcmp(s
, "user") == 0)
264 v9ses
->flags
|= V9FS_ACCESS_USER
;
265 else if (strcmp(s
, "any") == 0)
266 v9ses
->flags
|= V9FS_ACCESS_ANY
;
267 else if (strcmp(s
, "client") == 0) {
268 v9ses
->flags
|= V9FS_ACCESS_CLIENT
;
271 v9ses
->flags
|= V9FS_ACCESS_SINGLE
;
272 uid
= simple_strtoul(s
, &e
, 10);
275 pr_info("Unknown access argument %s\n",
278 goto free_and_return
;
280 v9ses
->uid
= make_kuid(current_user_ns(), uid
);
281 if (!uid_valid(v9ses
->uid
)) {
283 pr_info("Uknown uid %s\n", s
);
285 goto free_and_return
;
293 #ifdef CONFIG_9P_FS_POSIX_ACL
294 v9ses
->flags
|= V9FS_POSIX_ACL
;
296 p9_debug(P9_DEBUG_ERROR
,
297 "Not defined CONFIG_9P_FS_POSIX_ACL. Ignoring posixacl option\n");
313 * v9fs_session_init - initialize session
314 * @v9ses: session information structure
315 * @dev_name: device being mounted
320 struct p9_fid
*v9fs_session_init(struct v9fs_session_info
*v9ses
,
321 const char *dev_name
, char *data
)
326 v9ses
->uname
= kstrdup(V9FS_DEFUSER
, GFP_KERNEL
);
330 v9ses
->aname
= kstrdup(V9FS_DEFANAME
, GFP_KERNEL
);
333 init_rwsem(&v9ses
->rename_sem
);
335 rc
= bdi_setup_and_register(&v9ses
->bdi
, "9p");
339 v9ses
->uid
= INVALID_UID
;
340 v9ses
->dfltuid
= V9FS_DEFUID
;
341 v9ses
->dfltgid
= V9FS_DEFGID
;
343 v9ses
->clnt
= p9_client_create(dev_name
, data
);
344 if (IS_ERR(v9ses
->clnt
)) {
345 rc
= PTR_ERR(v9ses
->clnt
);
346 p9_debug(P9_DEBUG_ERROR
, "problem initializing 9p client\n");
350 v9ses
->flags
= V9FS_ACCESS_USER
;
352 if (p9_is_proto_dotl(v9ses
->clnt
)) {
353 v9ses
->flags
= V9FS_ACCESS_CLIENT
;
354 v9ses
->flags
|= V9FS_PROTO_2000L
;
355 } else if (p9_is_proto_dotu(v9ses
->clnt
)) {
356 v9ses
->flags
|= V9FS_PROTO_2000U
;
359 rc
= v9fs_parse_options(v9ses
, data
);
363 v9ses
->maxdata
= v9ses
->clnt
->msize
- P9_IOHDRSZ
;
365 if (!v9fs_proto_dotl(v9ses
) &&
366 ((v9ses
->flags
& V9FS_ACCESS_MASK
) == V9FS_ACCESS_CLIENT
)) {
368 * We support ACCESS_CLIENT only for dotl.
369 * Fall back to ACCESS_USER
371 v9ses
->flags
&= ~V9FS_ACCESS_MASK
;
372 v9ses
->flags
|= V9FS_ACCESS_USER
;
375 /* for legacy mode, fall back to V9FS_ACCESS_ANY */
376 if (!(v9fs_proto_dotu(v9ses
) || v9fs_proto_dotl(v9ses
)) &&
377 ((v9ses
->flags
&V9FS_ACCESS_MASK
) == V9FS_ACCESS_USER
)) {
379 v9ses
->flags
&= ~V9FS_ACCESS_MASK
;
380 v9ses
->flags
|= V9FS_ACCESS_ANY
;
381 v9ses
->uid
= INVALID_UID
;
383 if (!v9fs_proto_dotl(v9ses
) ||
384 !((v9ses
->flags
& V9FS_ACCESS_MASK
) == V9FS_ACCESS_CLIENT
)) {
386 * We support ACL checks on clinet only if the protocol is
387 * 9P2000.L and access is V9FS_ACCESS_CLIENT.
389 v9ses
->flags
&= ~V9FS_ACL_MASK
;
392 fid
= p9_client_attach(v9ses
->clnt
, NULL
, v9ses
->uname
, INVALID_UID
,
396 p9_debug(P9_DEBUG_ERROR
, "cannot attach\n");
400 if ((v9ses
->flags
& V9FS_ACCESS_MASK
) == V9FS_ACCESS_SINGLE
)
401 fid
->uid
= v9ses
->uid
;
403 fid
->uid
= INVALID_UID
;
405 #ifdef CONFIG_9P_FSCACHE
406 /* register the session for caching */
407 v9fs_cache_session_get_cookie(v9ses
);
409 spin_lock(&v9fs_sessionlist_lock
);
410 list_add(&v9ses
->slist
, &v9fs_sessionlist
);
411 spin_unlock(&v9fs_sessionlist_lock
);
416 p9_client_destroy(v9ses
->clnt
);
418 bdi_destroy(&v9ses
->bdi
);
426 * v9fs_session_close - shutdown a session
427 * @v9ses: session information structure
431 void v9fs_session_close(struct v9fs_session_info
*v9ses
)
434 p9_client_destroy(v9ses
->clnt
);
438 #ifdef CONFIG_9P_FSCACHE
439 if (v9ses
->fscache
) {
440 v9fs_cache_session_put_cookie(v9ses
);
441 kfree(v9ses
->cachetag
);
447 bdi_destroy(&v9ses
->bdi
);
449 spin_lock(&v9fs_sessionlist_lock
);
450 list_del(&v9ses
->slist
);
451 spin_unlock(&v9fs_sessionlist_lock
);
455 * v9fs_session_cancel - terminate a session
456 * @v9ses: session to terminate
458 * mark transport as disconnected and cancel all pending requests.
461 void v9fs_session_cancel(struct v9fs_session_info
*v9ses
) {
462 p9_debug(P9_DEBUG_ERROR
, "cancel session %p\n", v9ses
);
463 p9_client_disconnect(v9ses
->clnt
);
467 * v9fs_session_begin_cancel - Begin terminate of a session
468 * @v9ses: session to terminate
470 * After this call we don't allow any request other than clunk.
473 void v9fs_session_begin_cancel(struct v9fs_session_info
*v9ses
)
475 p9_debug(P9_DEBUG_ERROR
, "begin cancel session %p\n", v9ses
);
476 p9_client_begin_disconnect(v9ses
->clnt
);
479 extern int v9fs_error_init(void);
481 static struct kobject
*v9fs_kobj
;
483 #ifdef CONFIG_9P_FSCACHE
485 * caches_show - list caches associated with a session
487 * Returns the size of buffer written.
490 static ssize_t
caches_show(struct kobject
*kobj
,
491 struct kobj_attribute
*attr
,
494 ssize_t n
= 0, count
= 0, limit
= PAGE_SIZE
;
495 struct v9fs_session_info
*v9ses
;
497 spin_lock(&v9fs_sessionlist_lock
);
498 list_for_each_entry(v9ses
, &v9fs_sessionlist
, slist
) {
499 if (v9ses
->cachetag
) {
500 n
= snprintf(buf
, limit
, "%s\n", v9ses
->cachetag
);
511 spin_unlock(&v9fs_sessionlist_lock
);
515 static struct kobj_attribute v9fs_attr_cache
= __ATTR_RO(caches
);
516 #endif /* CONFIG_9P_FSCACHE */
518 static struct attribute
*v9fs_attrs
[] = {
519 #ifdef CONFIG_9P_FSCACHE
520 &v9fs_attr_cache
.attr
,
525 static struct attribute_group v9fs_attr_group
= {
530 * v9fs_sysfs_init - Initialize the v9fs sysfs interface
534 static int __init
v9fs_sysfs_init(void)
536 v9fs_kobj
= kobject_create_and_add("9p", fs_kobj
);
540 if (sysfs_create_group(v9fs_kobj
, &v9fs_attr_group
)) {
541 kobject_put(v9fs_kobj
);
549 * v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface
553 static void v9fs_sysfs_cleanup(void)
555 sysfs_remove_group(v9fs_kobj
, &v9fs_attr_group
);
556 kobject_put(v9fs_kobj
);
559 static void v9fs_inode_init_once(void *foo
)
561 struct v9fs_inode
*v9inode
= (struct v9fs_inode
*)foo
;
562 #ifdef CONFIG_9P_FSCACHE
563 v9inode
->fscache
= NULL
;
565 memset(&v9inode
->qid
, 0, sizeof(v9inode
->qid
));
566 inode_init_once(&v9inode
->vfs_inode
);
570 * v9fs_init_inode_cache - initialize a cache for 9P
571 * Returns 0 on success.
573 static int v9fs_init_inode_cache(void)
575 v9fs_inode_cache
= kmem_cache_create("v9fs_inode_cache",
576 sizeof(struct v9fs_inode
),
577 0, (SLAB_RECLAIM_ACCOUNT
|
578 SLAB_MEM_SPREAD
|SLAB_ACCOUNT
),
579 v9fs_inode_init_once
);
580 if (!v9fs_inode_cache
)
587 * v9fs_destroy_inode_cache - destroy the cache of 9P inode
590 static void v9fs_destroy_inode_cache(void)
593 * Make sure all delayed rcu free inodes are flushed before we
597 kmem_cache_destroy(v9fs_inode_cache
);
600 static int v9fs_cache_register(void)
603 ret
= v9fs_init_inode_cache();
606 #ifdef CONFIG_9P_FSCACHE
607 ret
= fscache_register_netfs(&v9fs_cache_netfs
);
609 v9fs_destroy_inode_cache();
614 static void v9fs_cache_unregister(void)
616 v9fs_destroy_inode_cache();
617 #ifdef CONFIG_9P_FSCACHE
618 fscache_unregister_netfs(&v9fs_cache_netfs
);
623 * init_v9fs - Initialize module
627 static int __init
init_v9fs(void)
630 pr_info("Installing v9fs 9p2000 file system support\n");
631 /* TODO: Setup list of registered trasnport modules */
633 err
= v9fs_cache_register();
635 pr_err("Failed to register v9fs for caching\n");
639 err
= v9fs_sysfs_init();
641 pr_err("Failed to register with sysfs\n");
644 err
= register_filesystem(&v9fs_fs_type
);
646 pr_err("Failed to register filesystem\n");
647 goto out_sysfs_cleanup
;
653 v9fs_sysfs_cleanup();
656 v9fs_cache_unregister();
662 * exit_v9fs - shutdown module
666 static void __exit
exit_v9fs(void)
668 v9fs_sysfs_cleanup();
669 v9fs_cache_unregister();
670 unregister_filesystem(&v9fs_fs_type
);
673 module_init(init_v9fs
)
674 module_exit(exit_v9fs
)
676 MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
677 MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
678 MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
679 MODULE_LICENSE("GPL");