x86/mm/pat: Don't report PAT on CPUs that don't support it
[linux/fpc-iii.git] / fs / 9p / v9fs.c
bloba89f3cfe3c7d7fba5341ee5adac4a3a1ecd8adec
1 /*
2 * linux/fs/9p/v9fs.c
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>
30 #include <linux/fs.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>
39 #include "v9fs.h"
40 #include "v9fs_vfs.h"
41 #include "cache.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
52 enum {
53 /* Options that take integer arguments */
54 Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid,
55 /* String options */
56 Opt_uname, Opt_remotename, Opt_cache, Opt_cachetag,
57 /* Options that take no arguments */
58 Opt_nodevmap,
59 /* Cache options */
60 Opt_cache_loose, Opt_fscache, Opt_mmap,
61 /* Access options */
62 Opt_access, Opt_posixacl,
63 /* Error token */
64 Opt_err
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"},
78 {Opt_mmap, "mmap"},
79 {Opt_cachetag, "cachetag=%s"},
80 {Opt_access, "access=%s"},
81 {Opt_posixacl, "posixacl"},
82 {Opt_err, NULL}
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")) {
97 version = CACHE_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");
102 } else
103 pr_info("Unknown Cache mode %s\n", s);
104 return version;
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];
118 char *p;
119 int option = 0;
120 char *s, *e;
121 int ret = 0;
123 /* setup defaults */
124 v9ses->afid = ~0;
125 v9ses->debug = 0;
126 v9ses->cache = CACHE_NONE;
127 #ifdef CONFIG_9P_FSCACHE
128 v9ses->cachetag = NULL;
129 #endif
131 if (!opts)
132 return 0;
134 tmp_options = kstrdup(opts, GFP_KERNEL);
135 if (!tmp_options) {
136 ret = -ENOMEM;
137 goto fail_option_alloc;
139 options = tmp_options;
141 while ((p = strsep(&options, ",")) != NULL) {
142 int token, r;
143 if (!*p)
144 continue;
145 token = match_token(p, tokens, args);
146 switch (token) {
147 case Opt_debug:
148 r = match_int(&args[0], &option);
149 if (r < 0) {
150 p9_debug(P9_DEBUG_ERROR,
151 "integer field, but no integer?\n");
152 ret = r;
153 continue;
155 v9ses->debug = option;
156 #ifdef CONFIG_NET_9P_DEBUG
157 p9_debug_level = option;
158 #endif
159 break;
161 case Opt_dfltuid:
162 r = match_int(&args[0], &option);
163 if (r < 0) {
164 p9_debug(P9_DEBUG_ERROR,
165 "integer field, but no integer?\n");
166 ret = r;
167 continue;
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");
173 ret = -EINVAL;
174 continue;
176 break;
177 case Opt_dfltgid:
178 r = match_int(&args[0], &option);
179 if (r < 0) {
180 p9_debug(P9_DEBUG_ERROR,
181 "integer field, but no integer?\n");
182 ret = r;
183 continue;
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");
189 ret = -EINVAL;
190 continue;
192 break;
193 case Opt_afid:
194 r = match_int(&args[0], &option);
195 if (r < 0) {
196 p9_debug(P9_DEBUG_ERROR,
197 "integer field, but no integer?\n");
198 ret = r;
199 continue;
201 v9ses->afid = option;
202 break;
203 case Opt_uname:
204 kfree(v9ses->uname);
205 v9ses->uname = match_strdup(&args[0]);
206 if (!v9ses->uname) {
207 ret = -ENOMEM;
208 goto free_and_return;
210 break;
211 case Opt_remotename:
212 kfree(v9ses->aname);
213 v9ses->aname = match_strdup(&args[0]);
214 if (!v9ses->aname) {
215 ret = -ENOMEM;
216 goto free_and_return;
218 break;
219 case Opt_nodevmap:
220 v9ses->nodev = 1;
221 break;
222 case Opt_cache_loose:
223 v9ses->cache = CACHE_LOOSE;
224 break;
225 case Opt_fscache:
226 v9ses->cache = CACHE_FSCACHE;
227 break;
228 case Opt_mmap:
229 v9ses->cache = CACHE_MMAP;
230 break;
231 case Opt_cachetag:
232 #ifdef CONFIG_9P_FSCACHE
233 v9ses->cachetag = match_strdup(&args[0]);
234 #endif
235 break;
236 case Opt_cache:
237 s = match_strdup(&args[0]);
238 if (!s) {
239 ret = -ENOMEM;
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) {
246 kfree(s);
247 goto free_and_return;
250 v9ses->cache = ret;
251 kfree(s);
252 break;
254 case Opt_access:
255 s = match_strdup(&args[0]);
256 if (!s) {
257 ret = -ENOMEM;
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;
270 } else {
271 uid_t uid;
272 v9ses->flags |= V9FS_ACCESS_SINGLE;
273 uid = simple_strtoul(s, &e, 10);
274 if (*e != '\0') {
275 ret = -EINVAL;
276 pr_info("Unknown access argument %s\n",
278 kfree(s);
279 goto free_and_return;
281 v9ses->uid = make_kuid(current_user_ns(), uid);
282 if (!uid_valid(v9ses->uid)) {
283 ret = -EINVAL;
284 pr_info("Uknown uid %s\n", s);
285 kfree(s);
286 goto free_and_return;
290 kfree(s);
291 break;
293 case Opt_posixacl:
294 #ifdef CONFIG_9P_FS_POSIX_ACL
295 v9ses->flags |= V9FS_POSIX_ACL;
296 #else
297 p9_debug(P9_DEBUG_ERROR,
298 "Not defined CONFIG_9P_FS_POSIX_ACL. Ignoring posixacl option\n");
299 #endif
300 break;
302 default:
303 continue;
307 free_and_return:
308 kfree(tmp_options);
309 fail_option_alloc:
310 return ret;
314 * v9fs_session_init - initialize session
315 * @v9ses: session information structure
316 * @dev_name: device being mounted
317 * @data: options
321 struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
322 const char *dev_name, char *data)
324 struct p9_fid *fid;
325 int rc = -ENOMEM;
327 v9ses->uname = kstrdup(V9FS_DEFUSER, GFP_KERNEL);
328 if (!v9ses->uname)
329 goto err_names;
331 v9ses->aname = kstrdup(V9FS_DEFANAME, GFP_KERNEL);
332 if (!v9ses->aname)
333 goto err_names;
334 init_rwsem(&v9ses->rename_sem);
336 rc = bdi_setup_and_register(&v9ses->bdi, "9p");
337 if (rc)
338 goto err_names;
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");
348 goto err_bdi;
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);
361 if (rc < 0)
362 goto err_clnt;
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;
375 /*FIXME !! */
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,
394 v9ses->aname);
395 if (IS_ERR(fid)) {
396 rc = PTR_ERR(fid);
397 p9_debug(P9_DEBUG_ERROR, "cannot attach\n");
398 goto err_clnt;
401 if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
402 fid->uid = v9ses->uid;
403 else
404 fid->uid = INVALID_UID;
406 #ifdef CONFIG_9P_FSCACHE
407 /* register the session for caching */
408 v9fs_cache_session_get_cookie(v9ses);
409 #endif
410 spin_lock(&v9fs_sessionlist_lock);
411 list_add(&v9ses->slist, &v9fs_sessionlist);
412 spin_unlock(&v9fs_sessionlist_lock);
414 return fid;
416 err_clnt:
417 p9_client_destroy(v9ses->clnt);
418 err_bdi:
419 bdi_destroy(&v9ses->bdi);
420 err_names:
421 kfree(v9ses->uname);
422 kfree(v9ses->aname);
423 return ERR_PTR(rc);
427 * v9fs_session_close - shutdown a session
428 * @v9ses: session information structure
432 void v9fs_session_close(struct v9fs_session_info *v9ses)
434 if (v9ses->clnt) {
435 p9_client_destroy(v9ses->clnt);
436 v9ses->clnt = NULL;
439 #ifdef CONFIG_9P_FSCACHE
440 if (v9ses->fscache) {
441 v9fs_cache_session_put_cookie(v9ses);
442 kfree(v9ses->cachetag);
444 #endif
445 kfree(v9ses->uname);
446 kfree(v9ses->aname);
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,
493 char *buf)
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);
502 if (n < 0) {
503 count = n;
504 break;
507 count += n;
508 limit -= n;
512 spin_unlock(&v9fs_sessionlist_lock);
513 return count;
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,
522 #endif
523 NULL,
526 static struct attribute_group v9fs_attr_group = {
527 .attrs = v9fs_attrs,
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);
538 if (!v9fs_kobj)
539 return -ENOMEM;
541 if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) {
542 kobject_put(v9fs_kobj);
543 return -ENOMEM;
546 return 0;
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;
565 #endif
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)
582 return -ENOMEM;
584 return 0;
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
595 * destroy cache.
597 rcu_barrier();
598 kmem_cache_destroy(v9fs_inode_cache);
601 static int v9fs_cache_register(void)
603 int ret;
604 ret = v9fs_init_inode_cache();
605 if (ret < 0)
606 return ret;
607 #ifdef CONFIG_9P_FSCACHE
608 ret = fscache_register_netfs(&v9fs_cache_netfs);
609 if (ret < 0)
610 v9fs_destroy_inode_cache();
611 #endif
612 return ret;
615 static void v9fs_cache_unregister(void)
617 v9fs_destroy_inode_cache();
618 #ifdef CONFIG_9P_FSCACHE
619 fscache_unregister_netfs(&v9fs_cache_netfs);
620 #endif
624 * init_v9fs - Initialize module
628 static int __init init_v9fs(void)
630 int err;
631 pr_info("Installing v9fs 9p2000 file system support\n");
632 /* TODO: Setup list of registered trasnport modules */
634 err = v9fs_cache_register();
635 if (err < 0) {
636 pr_err("Failed to register v9fs for caching\n");
637 return err;
640 err = v9fs_sysfs_init();
641 if (err < 0) {
642 pr_err("Failed to register with sysfs\n");
643 goto out_cache;
645 err = register_filesystem(&v9fs_fs_type);
646 if (err < 0) {
647 pr_err("Failed to register filesystem\n");
648 goto out_sysfs_cleanup;
651 return 0;
653 out_sysfs_cleanup:
654 v9fs_sysfs_cleanup();
656 out_cache:
657 v9fs_cache_unregister();
659 return err;
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)
677 MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
678 MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
679 MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
680 MODULE_LICENSE("GPL");