4 * This file contains functions assisting in mapping VFS to 9P2000
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/cred.h>
33 #include <linux/parser.h>
34 #include <linux/idr.h>
35 #include <linux/slab.h>
36 #include <net/9p/9p.h>
37 #include <net/9p/client.h>
38 #include <net/9p/transport.h>
43 static DEFINE_SPINLOCK(v9fs_sessionlist_lock);
44 static LIST_HEAD(v9fs_sessionlist);
45 struct kmem_cache *v9fs_inode_cache;
48 * Option Parsing (code inspired by NFS code)
49 * NOTE: each transport will parse its own options
53 /* Options that take integer arguments */
54 Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid,
56 Opt_uname, Opt_remotename, Opt_cache, Opt_cachetag,
57 /* Options that take no arguments */
60 Opt_cache_loose, Opt_fscache, Opt_mmap,
62 Opt_access, Opt_posixacl,
67 static const match_table_t tokens = {
68 {Opt_debug, "debug=%x"},
69 {Opt_dfltuid, "dfltuid=%u"},
70 {Opt_dfltgid, "dfltgid=%u"},
71 {Opt_afid, "afid=%u"},
72 {Opt_uname, "uname=%s"},
73 {Opt_remotename, "aname=%s"},
74 {Opt_nodevmap, "nodevmap"},
75 {Opt_cache, "cache=%s"},
76 {Opt_cache_loose, "loose"},
77 {Opt_fscache, "fscache"},
79 {Opt_cachetag, "cachetag=%s"},
80 {Opt_access, "access=%s"},
81 {Opt_posixacl, "posixacl"},
85 /* Interpret mount options for cache mode */
86 static int get_cache_mode(char *s)
88 int version = -EINVAL;
90 if (!strcmp(s, "loose")) {
91 version = CACHE_LOOSE;
92 p9_debug(P9_DEBUG_9P, "Cache mode: loose\n");
93 } else if (!strcmp(s, "fscache")) {
94 version = CACHE_FSCACHE;
95 p9_debug(P9_DEBUG_9P, "Cache mode: fscache\n");
96 } else if (!strcmp(s, "mmap")) {
98 p9_debug(P9_DEBUG_9P, "Cache mode: mmap\n");
99 } else if (!strcmp(s, "none")) {
100 version = CACHE_NONE;
101 p9_debug(P9_DEBUG_9P, "Cache mode: none\n");
103 pr_info("Unknown Cache mode %s\n", s);
108 * v9fs_parse_options - parse mount options into session structure
109 * @v9ses: existing v9fs session information
111 * Return 0 upon success, -ERRNO upon failure.
114 static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
116 char *options, *tmp_options;
117 substring_t args[MAX_OPT_ARGS];
126 v9ses->cache = CACHE_NONE;
127 #ifdef CONFIG_9P_FSCACHE
128 v9ses->cachetag = NULL;
134 tmp_options = kstrdup(opts, GFP_KERNEL);
137 goto fail_option_alloc;
139 options = tmp_options;
141 while ((p = strsep(&options, ",")) != NULL) {
145 token = match_token(p, tokens, args);
148 r = match_int(&args[0], &option);
150 p9_debug(P9_DEBUG_ERROR,
151 "integer field, but no integer?\n");
155 v9ses->debug = option;
156 #ifdef CONFIG_NET_9P_DEBUG
157 p9_debug_level = option;
162 r = match_int(&args[0], &option);
164 p9_debug(P9_DEBUG_ERROR,
165 "integer field, but no integer?\n");
169 v9ses->dfltuid = make_kuid(current_user_ns(), option);
170 if (!uid_valid(v9ses->dfltuid)) {
171 p9_debug(P9_DEBUG_ERROR,
172 "uid field, but not a uid?\n");
178 r = match_int(&args[0], &option);
180 p9_debug(P9_DEBUG_ERROR,
181 "integer field, but no integer?\n");
185 v9ses->dfltgid = make_kgid(current_user_ns(), option);
186 if (!gid_valid(v9ses->dfltgid)) {
187 p9_debug(P9_DEBUG_ERROR,
188 "gid field, but not a gid?\n");
194 r = match_int(&args[0], &option);
196 p9_debug(P9_DEBUG_ERROR,
197 "integer field, but no integer?\n");
201 v9ses->afid = option;
205 v9ses->uname = match_strdup(&args[0]);
208 goto free_and_return;
213 v9ses->aname = match_strdup(&args[0]);
216 goto free_and_return;
222 case Opt_cache_loose:
223 v9ses->cache = CACHE_LOOSE;
226 v9ses->cache = CACHE_FSCACHE;
229 v9ses->cache = CACHE_MMAP;
232 #ifdef CONFIG_9P_FSCACHE
233 v9ses->cachetag = match_strdup(&args[0]);
237 s = match_strdup(&args[0]);
240 p9_debug(P9_DEBUG_ERROR,
241 "problem allocating copy of cache arg\n");
242 goto free_and_return;
244 ret = get_cache_mode(s);
245 if (ret == -EINVAL) {
247 goto free_and_return;
255 s = match_strdup(&args[0]);
258 p9_debug(P9_DEBUG_ERROR,
259 "problem allocating copy of access arg\n");
260 goto free_and_return;
263 v9ses->flags &= ~V9FS_ACCESS_MASK;
264 if (strcmp(s, "user") == 0)
265 v9ses->flags |= V9FS_ACCESS_USER;
266 else if (strcmp(s, "any") == 0)
267 v9ses->flags |= V9FS_ACCESS_ANY;
268 else if (strcmp(s, "client") == 0) {
269 v9ses->flags |= V9FS_ACCESS_CLIENT;
272 v9ses->flags |= V9FS_ACCESS_SINGLE;
273 uid = simple_strtoul(s, &e, 10);
276 pr_info("Unknown access argument %s\n",
279 goto free_and_return;
281 v9ses->uid = make_kuid(current_user_ns(), uid);
282 if (!uid_valid(v9ses->uid)) {
284 pr_info("Uknown uid %s\n", s);
286 goto free_and_return;
294 #ifdef CONFIG_9P_FS_POSIX_ACL
295 v9ses->flags |= V9FS_POSIX_ACL;
297 p9_debug(P9_DEBUG_ERROR,
298 "Not defined CONFIG_9P_FS_POSIX_ACL. Ignoring posixacl option\n");
314 * v9fs_session_init - initialize session
315 * @v9ses: session information structure
316 * @dev_name: device being mounted
321 struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
322 const char *dev_name, char *data)
327 v9ses->uname = kstrdup(V9FS_DEFUSER, GFP_KERNEL);
331 v9ses->aname = kstrdup(V9FS_DEFANAME, GFP_KERNEL);
334 init_rwsem(&v9ses->rename_sem);
336 rc = bdi_setup_and_register(&v9ses->bdi, "9p");
340 v9ses->uid = INVALID_UID;
341 v9ses->dfltuid = V9FS_DEFUID;
342 v9ses->dfltgid = V9FS_DEFGID;
344 v9ses->clnt = p9_client_create(dev_name, data);
345 if (IS_ERR(v9ses->clnt)) {
346 rc = PTR_ERR(v9ses->clnt);
347 p9_debug(P9_DEBUG_ERROR, "problem initializing 9p client\n");
351 v9ses->flags = V9FS_ACCESS_USER;
353 if (p9_is_proto_dotl(v9ses->clnt)) {
354 v9ses->flags = V9FS_ACCESS_CLIENT;
355 v9ses->flags |= V9FS_PROTO_2000L;
356 } else if (p9_is_proto_dotu(v9ses->clnt)) {
357 v9ses->flags |= V9FS_PROTO_2000U;
360 rc = v9fs_parse_options(v9ses, data);
364 v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;
366 if (!v9fs_proto_dotl(v9ses) &&
367 ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
369 * We support ACCESS_CLIENT only for dotl.
370 * Fall back to ACCESS_USER
372 v9ses->flags &= ~V9FS_ACCESS_MASK;
373 v9ses->flags |= V9FS_ACCESS_USER;
376 /* for legacy mode, fall back to V9FS_ACCESS_ANY */
377 if (!(v9fs_proto_dotu(v9ses) || v9fs_proto_dotl(v9ses)) &&
378 ((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {
380 v9ses->flags &= ~V9FS_ACCESS_MASK;
381 v9ses->flags |= V9FS_ACCESS_ANY;
382 v9ses->uid = INVALID_UID;
384 if (!v9fs_proto_dotl(v9ses) ||
385 !((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
387 * We support ACL checks on clinet only if the protocol is
388 * 9P2000.L and access is V9FS_ACCESS_CLIENT.
390 v9ses->flags &= ~V9FS_ACL_MASK;
393 fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, INVALID_UID,
397 p9_debug(P9_DEBUG_ERROR, "cannot attach\n");
401 if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
402 fid->uid = v9ses->uid;
404 fid->uid = INVALID_UID;
406 #ifdef CONFIG_9P_FSCACHE
407 /* register the session for caching */
408 v9fs_cache_session_get_cookie(v9ses);
410 spin_lock(&v9fs_sessionlist_lock);
411 list_add(&v9ses->slist, &v9fs_sessionlist);
412 spin_unlock(&v9fs_sessionlist_lock);
417 p9_client_destroy(v9ses->clnt);
419 bdi_destroy(&v9ses->bdi);
427 * v9fs_session_close - shutdown a session
428 * @v9ses: session information structure
432 void v9fs_session_close(struct v9fs_session_info *v9ses)
435 p9_client_destroy(v9ses->clnt);
439 #ifdef CONFIG_9P_FSCACHE
440 if (v9ses->fscache) {
441 v9fs_cache_session_put_cookie(v9ses);
442 kfree(v9ses->cachetag);
448 bdi_destroy(&v9ses->bdi);
450 spin_lock(&v9fs_sessionlist_lock);
451 list_del(&v9ses->slist);
452 spin_unlock(&v9fs_sessionlist_lock);
456 * v9fs_session_cancel - terminate a session
457 * @v9ses: session to terminate
459 * mark transport as disconnected and cancel all pending requests.
462 void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
463 p9_debug(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
464 p9_client_disconnect(v9ses->clnt);
468 * v9fs_session_begin_cancel - Begin terminate of a session
469 * @v9ses: session to terminate
471 * After this call we don't allow any request other than clunk.
474 void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses)
476 p9_debug(P9_DEBUG_ERROR, "begin cancel session %p\n", v9ses);
477 p9_client_begin_disconnect(v9ses->clnt);
480 extern int v9fs_error_init(void);
482 static struct kobject *v9fs_kobj;
484 #ifdef CONFIG_9P_FSCACHE
486 * caches_show - list caches associated with a session
488 * Returns the size of buffer written.
491 static ssize_t caches_show(struct kobject *kobj,
492 struct kobj_attribute *attr,
495 ssize_t n = 0, count = 0, limit = PAGE_SIZE;
496 struct v9fs_session_info *v9ses;
498 spin_lock(&v9fs_sessionlist_lock);
499 list_for_each_entry(v9ses, &v9fs_sessionlist, slist) {
500 if (v9ses->cachetag) {
501 n = snprintf(buf, limit, "%s\n", v9ses->cachetag);
512 spin_unlock(&v9fs_sessionlist_lock);
516 static struct kobj_attribute v9fs_attr_cache = __ATTR_RO(caches);
517 #endif /* CONFIG_9P_FSCACHE */
519 static struct attribute *v9fs_attrs[] = {
520 #ifdef CONFIG_9P_FSCACHE
521 &v9fs_attr_cache.attr,
526 static struct attribute_group v9fs_attr_group = {
531 * v9fs_sysfs_init - Initialize the v9fs sysfs interface
535 static int __init v9fs_sysfs_init(void)
537 v9fs_kobj = kobject_create_and_add("9p", fs_kobj);
541 if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) {
542 kobject_put(v9fs_kobj);
550 * v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface
554 static void v9fs_sysfs_cleanup(void)
556 sysfs_remove_group(v9fs_kobj, &v9fs_attr_group);
557 kobject_put(v9fs_kobj);
560 static void v9fs_inode_init_once(void *foo)
562 struct v9fs_inode *v9inode = (struct v9fs_inode *)foo;
563 #ifdef CONFIG_9P_FSCACHE
564 v9inode->fscache = NULL;
566 memset(&v9inode->qid, 0, sizeof(v9inode->qid));
567 inode_init_once(&v9inode->vfs_inode);
571 * v9fs_init_inode_cache - initialize a cache for 9P
572 * Returns 0 on success.
574 static int v9fs_init_inode_cache(void)
576 v9fs_inode_cache = kmem_cache_create("v9fs_inode_cache",
577 sizeof(struct v9fs_inode),
578 0, (SLAB_RECLAIM_ACCOUNT|
579 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
580 v9fs_inode_init_once);
581 if (!v9fs_inode_cache)
588 * v9fs_destroy_inode_cache - destroy the cache of 9P inode
591 static void v9fs_destroy_inode_cache(void)
594 * Make sure all delayed rcu free inodes are flushed before we
598 kmem_cache_destroy(v9fs_inode_cache);
601 static int v9fs_cache_register(void)
604 ret = v9fs_init_inode_cache();
607 #ifdef CONFIG_9P_FSCACHE
608 ret = fscache_register_netfs(&v9fs_cache_netfs);
610 v9fs_destroy_inode_cache();
615 static void v9fs_cache_unregister(void)
617 v9fs_destroy_inode_cache();
618 #ifdef CONFIG_9P_FSCACHE
619 fscache_unregister_netfs(&v9fs_cache_netfs);
624 * init_v9fs - Initialize module
628 static int __init init_v9fs(void)
631 pr_info("Installing v9fs 9p2000 file system support\n");
632 /* TODO: Setup list of registered trasnport modules */
634 err = v9fs_cache_register();
636 pr_err("Failed to register v9fs for caching\n");
640 err = v9fs_sysfs_init();
642 pr_err("Failed to register with sysfs\n");
645 err = register_filesystem(&v9fs_fs_type);
647 pr_err("Failed to register filesystem\n");
648 goto out_sysfs_cleanup;
654 v9fs_sysfs_cleanup();
657 v9fs_cache_unregister();
663 * exit_v9fs - shutdown module
667 static void __exit exit_v9fs(void)
669 v9fs_sysfs_cleanup();
670 v9fs_cache_unregister();
671 unregister_filesystem(&v9fs_fs_type);
674 module_init(init_v9fs)
675 module_exit(exit_v9fs)
680 MODULE_LICENSE("GPL");