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1/*
2 * linux/fs/9p/v9fs.c
3 *
4 * This file contains functions assisting in mapping VFS to 9P2000
5 *
6 * Copyright (C) 2004-2008 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 version 2
11 * as published by the Free Software Foundation.
12 *
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.
17 *
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
23 *
24 */
25
26#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
27
28#include <linux/module.h>
29#include <linux/errno.h>
30#include <linux/fs.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>
38#include "v9fs.h"
39#include "v9fs_vfs.h"
40#include "cache.h"
41
42static DEFINE_SPINLOCK(v9fs_sessionlist_lock);
43static LIST_HEAD(v9fs_sessionlist);
44struct kmem_cache *v9fs_inode_cache;
45
46/*
47 * Option Parsing (code inspired by NFS code)
48 * NOTE: each transport will parse its own options
49 */
50
51enum {
52 /* Options that take integer arguments */
53 Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid,
54 /* String options */
55 Opt_uname, Opt_remotename, Opt_cache, Opt_cachetag,
56 /* Options that take no arguments */
57 Opt_nodevmap,
58 /* Cache options */
59 Opt_cache_loose, Opt_fscache, Opt_mmap,
60 /* Access options */
61 Opt_access, Opt_posixacl,
62 /* Error token */
63 Opt_err
64};
65
66static 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"},
77 {Opt_mmap, "mmap"},
78 {Opt_cachetag, "cachetag=%s"},
79 {Opt_access, "access=%s"},
80 {Opt_posixacl, "posixacl"},
81 {Opt_err, NULL}
82};
83
84/* Interpret mount options for cache mode */
85static int get_cache_mode(char *s)
86{
87 int version = -EINVAL;
88
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")) {
96 version = CACHE_MMAP;
97 p9_debug(P9_DEBUG_9P, "Cache mode: mmap\n");
98 } else if (!strcmp(s, "none")) {
99 version = CACHE_NONE;
100 p9_debug(P9_DEBUG_9P, "Cache mode: none\n");
101 } else
102 pr_info("Unknown Cache mode %s\n", s);
103 return version;
104}
105
106/**
107 * v9fs_parse_options - parse mount options into session structure
108 * @v9ses: existing v9fs session information
109 *
110 * Return 0 upon success, -ERRNO upon failure.
111 */
112
113static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
114{
115 char *options, *tmp_options;
116 substring_t args[MAX_OPT_ARGS];
117 char *p;
118 int option = 0;
119 char *s, *e;
120 int ret = 0;
121
122 /* setup defaults */
123 v9ses->afid = ~0;
124 v9ses->debug = 0;
125 v9ses->cache = CACHE_NONE;
126#ifdef CONFIG_9P_FSCACHE
127 v9ses->cachetag = NULL;
128#endif
129
130 if (!opts)
131 return 0;
132
133 tmp_options = kstrdup(opts, GFP_KERNEL);
134 if (!tmp_options) {
135 ret = -ENOMEM;
136 goto fail_option_alloc;
137 }
138 options = tmp_options;
139
140 while ((p = strsep(&options, ",")) != NULL) {
141 int token, r;
142 if (!*p)
143 continue;
144 token = match_token(p, tokens, args);
145 switch (token) {
146 case Opt_debug:
147 r = match_int(&args[0], &option);
148 if (r < 0) {
149 p9_debug(P9_DEBUG_ERROR,
150 "integer field, but no integer?\n");
151 ret = r;
152 continue;
153 }
154 v9ses->debug = option;
155#ifdef CONFIG_NET_9P_DEBUG
156 p9_debug_level = option;
157#endif
158 break;
159
160 case Opt_dfltuid:
161 r = match_int(&args[0], &option);
162 if (r < 0) {
163 p9_debug(P9_DEBUG_ERROR,
164 "integer field, but no integer?\n");
165 ret = r;
166 continue;
167 }
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");
172 ret = -EINVAL;
173 continue;
174 }
175 break;
176 case Opt_dfltgid:
177 r = match_int(&args[0], &option);
178 if (r < 0) {
179 p9_debug(P9_DEBUG_ERROR,
180 "integer field, but no integer?\n");
181 ret = r;
182 continue;
183 }
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");
188 ret = -EINVAL;
189 continue;
190 }
191 break;
192 case Opt_afid:
193 r = match_int(&args[0], &option);
194 if (r < 0) {
195 p9_debug(P9_DEBUG_ERROR,
196 "integer field, but no integer?\n");
197 ret = r;
198 continue;
199 }
200 v9ses->afid = option;
201 break;
202 case Opt_uname:
203 kfree(v9ses->uname);
204 v9ses->uname = match_strdup(&args[0]);
205 if (!v9ses->uname) {
206 ret = -ENOMEM;
207 goto free_and_return;
208 }
209 break;
210 case Opt_remotename:
211 kfree(v9ses->aname);
212 v9ses->aname = match_strdup(&args[0]);
213 if (!v9ses->aname) {
214 ret = -ENOMEM;
215 goto free_and_return;
216 }
217 break;
218 case Opt_nodevmap:
219 v9ses->nodev = 1;
220 break;
221 case Opt_cache_loose:
222 v9ses->cache = CACHE_LOOSE;
223 break;
224 case Opt_fscache:
225 v9ses->cache = CACHE_FSCACHE;
226 break;
227 case Opt_mmap:
228 v9ses->cache = CACHE_MMAP;
229 break;
230 case Opt_cachetag:
231#ifdef CONFIG_9P_FSCACHE
232 v9ses->cachetag = match_strdup(&args[0]);
233#endif
234 break;
235 case Opt_cache:
236 s = match_strdup(&args[0]);
237 if (!s) {
238 ret = -ENOMEM;
239 p9_debug(P9_DEBUG_ERROR,
240 "problem allocating copy of cache arg\n");
241 goto free_and_return;
242 }
243 ret = get_cache_mode(s);
244 if (ret == -EINVAL) {
245 kfree(s);
246 goto free_and_return;
247 }
248
249 v9ses->cache = ret;
250 kfree(s);
251 break;
252
253 case Opt_access:
254 s = match_strdup(&args[0]);
255 if (!s) {
256 ret = -ENOMEM;
257 p9_debug(P9_DEBUG_ERROR,
258 "problem allocating copy of access arg\n");
259 goto free_and_return;
260 }
261
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;
269 } else {
270 uid_t uid;
271 v9ses->flags |= V9FS_ACCESS_SINGLE;
272 uid = simple_strtoul(s, &e, 10);
273 if (*e != '\0') {
274 ret = -EINVAL;
275 pr_info("Unknown access argument %s\n",
276 s);
277 kfree(s);
278 goto free_and_return;
279 }
280 v9ses->uid = make_kuid(current_user_ns(), uid);
281 if (!uid_valid(v9ses->uid)) {
282 ret = -EINVAL;
283 pr_info("Uknown uid %s\n", s);
284 kfree(s);
285 goto free_and_return;
286 }
287 }
288
289 kfree(s);
290 break;
291
292 case Opt_posixacl:
293#ifdef CONFIG_9P_FS_POSIX_ACL
294 v9ses->flags |= V9FS_POSIX_ACL;
295#else
296 p9_debug(P9_DEBUG_ERROR,
297 "Not defined CONFIG_9P_FS_POSIX_ACL. Ignoring posixacl option\n");
298#endif
299 break;
300
301 default:
302 continue;
303 }
304 }
305
306free_and_return:
307 kfree(tmp_options);
308fail_option_alloc:
309 return ret;
310}
311
312/**
313 * v9fs_session_init - initialize session
314 * @v9ses: session information structure
315 * @dev_name: device being mounted
316 * @data: options
317 *
318 */
319
320struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
321 const char *dev_name, char *data)
322{
323 struct p9_fid *fid;
324 int rc = -ENOMEM;
325
326 v9ses->uname = kstrdup(V9FS_DEFUSER, GFP_KERNEL);
327 if (!v9ses->uname)
328 goto err_names;
329
330 v9ses->aname = kstrdup(V9FS_DEFANAME, GFP_KERNEL);
331 if (!v9ses->aname)
332 goto err_names;
333 init_rwsem(&v9ses->rename_sem);
334
335 rc = bdi_setup_and_register(&v9ses->bdi, "9p");
336 if (rc)
337 goto err_names;
338
339 v9ses->uid = INVALID_UID;
340 v9ses->dfltuid = V9FS_DEFUID;
341 v9ses->dfltgid = V9FS_DEFGID;
342
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");
347 goto err_bdi;
348 }
349
350 v9ses->flags = V9FS_ACCESS_USER;
351
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;
357 }
358
359 rc = v9fs_parse_options(v9ses, data);
360 if (rc < 0)
361 goto err_clnt;
362
363 v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;
364
365 if (!v9fs_proto_dotl(v9ses) &&
366 ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
367 /*
368 * We support ACCESS_CLIENT only for dotl.
369 * Fall back to ACCESS_USER
370 */
371 v9ses->flags &= ~V9FS_ACCESS_MASK;
372 v9ses->flags |= V9FS_ACCESS_USER;
373 }
374 /*FIXME !! */
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)) {
378
379 v9ses->flags &= ~V9FS_ACCESS_MASK;
380 v9ses->flags |= V9FS_ACCESS_ANY;
381 v9ses->uid = INVALID_UID;
382 }
383 if (!v9fs_proto_dotl(v9ses) ||
384 !((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
385 /*
386 * We support ACL checks on clinet only if the protocol is
387 * 9P2000.L and access is V9FS_ACCESS_CLIENT.
388 */
389 v9ses->flags &= ~V9FS_ACL_MASK;
390 }
391
392 fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, INVALID_UID,
393 v9ses->aname);
394 if (IS_ERR(fid)) {
395 rc = PTR_ERR(fid);
396 p9_debug(P9_DEBUG_ERROR, "cannot attach\n");
397 goto err_clnt;
398 }
399
400 if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
401 fid->uid = v9ses->uid;
402 else
403 fid->uid = INVALID_UID;
404
405#ifdef CONFIG_9P_FSCACHE
406 /* register the session for caching */
407 v9fs_cache_session_get_cookie(v9ses);
408#endif
409 spin_lock(&v9fs_sessionlist_lock);
410 list_add(&v9ses->slist, &v9fs_sessionlist);
411 spin_unlock(&v9fs_sessionlist_lock);
412
413 return fid;
414
415err_clnt:
416 p9_client_destroy(v9ses->clnt);
417err_bdi:
418 bdi_destroy(&v9ses->bdi);
419err_names:
420 kfree(v9ses->uname);
421 kfree(v9ses->aname);
422 return ERR_PTR(rc);
423}
424
425/**
426 * v9fs_session_close - shutdown a session
427 * @v9ses: session information structure
428 *
429 */
430
431void v9fs_session_close(struct v9fs_session_info *v9ses)
432{
433 if (v9ses->clnt) {
434 p9_client_destroy(v9ses->clnt);
435 v9ses->clnt = NULL;
436 }
437
438#ifdef CONFIG_9P_FSCACHE
439 if (v9ses->fscache) {
440 v9fs_cache_session_put_cookie(v9ses);
441 kfree(v9ses->cachetag);
442 }
443#endif
444 kfree(v9ses->uname);
445 kfree(v9ses->aname);
446
447 bdi_destroy(&v9ses->bdi);
448
449 spin_lock(&v9fs_sessionlist_lock);
450 list_del(&v9ses->slist);
451 spin_unlock(&v9fs_sessionlist_lock);
452}
453
454/**
455 * v9fs_session_cancel - terminate a session
456 * @v9ses: session to terminate
457 *
458 * mark transport as disconnected and cancel all pending requests.
459 */
460
461void 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);
464}
465
466/**
467 * v9fs_session_begin_cancel - Begin terminate of a session
468 * @v9ses: session to terminate
469 *
470 * After this call we don't allow any request other than clunk.
471 */
472
473void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses)
474{
475 p9_debug(P9_DEBUG_ERROR, "begin cancel session %p\n", v9ses);
476 p9_client_begin_disconnect(v9ses->clnt);
477}
478
479extern int v9fs_error_init(void);
480
481static struct kobject *v9fs_kobj;
482
483#ifdef CONFIG_9P_FSCACHE
484/**
485 * caches_show - list caches associated with a session
486 *
487 * Returns the size of buffer written.
488 */
489
490static ssize_t caches_show(struct kobject *kobj,
491 struct kobj_attribute *attr,
492 char *buf)
493{
494 ssize_t n = 0, count = 0, limit = PAGE_SIZE;
495 struct v9fs_session_info *v9ses;
496
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);
501 if (n < 0) {
502 count = n;
503 break;
504 }
505
506 count += n;
507 limit -= n;
508 }
509 }
510
511 spin_unlock(&v9fs_sessionlist_lock);
512 return count;
513}
514
515static struct kobj_attribute v9fs_attr_cache = __ATTR_RO(caches);
516#endif /* CONFIG_9P_FSCACHE */
517
518static struct attribute *v9fs_attrs[] = {
519#ifdef CONFIG_9P_FSCACHE
520 &v9fs_attr_cache.attr,
521#endif
522 NULL,
523};
524
525static struct attribute_group v9fs_attr_group = {
526 .attrs = v9fs_attrs,
527};
528
529/**
530 * v9fs_sysfs_init - Initialize the v9fs sysfs interface
531 *
532 */
533
534static int __init v9fs_sysfs_init(void)
535{
536 v9fs_kobj = kobject_create_and_add("9p", fs_kobj);
537 if (!v9fs_kobj)
538 return -ENOMEM;
539
540 if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) {
541 kobject_put(v9fs_kobj);
542 return -ENOMEM;
543 }
544
545 return 0;
546}
547
548/**
549 * v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface
550 *
551 */
552
553static void v9fs_sysfs_cleanup(void)
554{
555 sysfs_remove_group(v9fs_kobj, &v9fs_attr_group);
556 kobject_put(v9fs_kobj);
557}
558
559static void v9fs_inode_init_once(void *foo)
560{
561 struct v9fs_inode *v9inode = (struct v9fs_inode *)foo;
562#ifdef CONFIG_9P_FSCACHE
563 v9inode->fscache = NULL;
564#endif
565 memset(&v9inode->qid, 0, sizeof(v9inode->qid));
566 inode_init_once(&v9inode->vfs_inode);
567}
568
569/**
570 * v9fs_init_inode_cache - initialize a cache for 9P
571 * Returns 0 on success.
572 */
573static int v9fs_init_inode_cache(void)
574{
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)
581 return -ENOMEM;
582
583 return 0;
584}
585
586/**
587 * v9fs_destroy_inode_cache - destroy the cache of 9P inode
588 *
589 */
590static void v9fs_destroy_inode_cache(void)
591{
592 /*
593 * Make sure all delayed rcu free inodes are flushed before we
594 * destroy cache.
595 */
596 rcu_barrier();
597 kmem_cache_destroy(v9fs_inode_cache);
598}
599
600static int v9fs_cache_register(void)
601{
602 int ret;
603 ret = v9fs_init_inode_cache();
604 if (ret < 0)
605 return ret;
606#ifdef CONFIG_9P_FSCACHE
607 ret = fscache_register_netfs(&v9fs_cache_netfs);
608 if (ret < 0)
609 v9fs_destroy_inode_cache();
610#endif
611 return ret;
612}
613
614static void v9fs_cache_unregister(void)
615{
616 v9fs_destroy_inode_cache();
617#ifdef CONFIG_9P_FSCACHE
618 fscache_unregister_netfs(&v9fs_cache_netfs);
619#endif
620}
621
622/**
623 * init_v9fs - Initialize module
624 *
625 */
626
627static int __init init_v9fs(void)
628{
629 int err;
630 pr_info("Installing v9fs 9p2000 file system support\n");
631 /* TODO: Setup list of registered trasnport modules */
632
633 err = v9fs_cache_register();
634 if (err < 0) {
635 pr_err("Failed to register v9fs for caching\n");
636 return err;
637 }
638
639 err = v9fs_sysfs_init();
640 if (err < 0) {
641 pr_err("Failed to register with sysfs\n");
642 goto out_cache;
643 }
644 err = register_filesystem(&v9fs_fs_type);
645 if (err < 0) {
646 pr_err("Failed to register filesystem\n");
647 goto out_sysfs_cleanup;
648 }
649
650 return 0;
651
652out_sysfs_cleanup:
653 v9fs_sysfs_cleanup();
654
655out_cache:
656 v9fs_cache_unregister();
657
658 return err;
659}
660
661/**
662 * exit_v9fs - shutdown module
663 *
664 */
665
666static void __exit exit_v9fs(void)
667{
668 v9fs_sysfs_cleanup();
669 v9fs_cache_unregister();
670 unregister_filesystem(&v9fs_fs_type);
671}
672
673module_init(init_v9fs)
674module_exit(exit_v9fs)
675
676MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
677MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
678MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
679MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * This file contains functions assisting in mapping VFS to 9P2000
4 *
5 * Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
6 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
7 */
8
9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10
11#include <linux/module.h>
12#include <linux/errno.h>
13#include <linux/fs.h>
14#include <linux/sched.h>
15#include <linux/cred.h>
16#include <linux/parser.h>
17#include <linux/slab.h>
18#include <linux/seq_file.h>
19#include <net/9p/9p.h>
20#include <net/9p/client.h>
21#include <net/9p/transport.h>
22#include "v9fs.h"
23#include "v9fs_vfs.h"
24#include "cache.h"
25
26static DEFINE_SPINLOCK(v9fs_sessionlist_lock);
27static LIST_HEAD(v9fs_sessionlist);
28struct kmem_cache *v9fs_inode_cache;
29
30/*
31 * Option Parsing (code inspired by NFS code)
32 * NOTE: each transport will parse its own options
33 */
34
35enum {
36 /* Options that take integer arguments */
37 Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid,
38 /* String options */
39 Opt_uname, Opt_remotename, Opt_cache, Opt_cachetag,
40 /* Options that take no arguments */
41 Opt_nodevmap, Opt_noxattr, Opt_directio, Opt_ignoreqv,
42 /* Access options */
43 Opt_access, Opt_posixacl,
44 /* Lock timeout option */
45 Opt_locktimeout,
46 /* Error token */
47 Opt_err
48};
49
50static const match_table_t tokens = {
51 {Opt_debug, "debug=%x"},
52 {Opt_dfltuid, "dfltuid=%u"},
53 {Opt_dfltgid, "dfltgid=%u"},
54 {Opt_afid, "afid=%u"},
55 {Opt_uname, "uname=%s"},
56 {Opt_remotename, "aname=%s"},
57 {Opt_nodevmap, "nodevmap"},
58 {Opt_noxattr, "noxattr"},
59 {Opt_directio, "directio"},
60 {Opt_ignoreqv, "ignoreqv"},
61 {Opt_cache, "cache=%s"},
62 {Opt_cachetag, "cachetag=%s"},
63 {Opt_access, "access=%s"},
64 {Opt_posixacl, "posixacl"},
65 {Opt_locktimeout, "locktimeout=%u"},
66 {Opt_err, NULL}
67};
68
69/* Interpret mount options for cache mode */
70static int get_cache_mode(char *s)
71{
72 int version = -EINVAL;
73
74 if (!strcmp(s, "loose")) {
75 version = CACHE_SC_LOOSE;
76 p9_debug(P9_DEBUG_9P, "Cache mode: loose\n");
77 } else if (!strcmp(s, "fscache")) {
78 version = CACHE_SC_FSCACHE;
79 p9_debug(P9_DEBUG_9P, "Cache mode: fscache\n");
80 } else if (!strcmp(s, "mmap")) {
81 version = CACHE_SC_MMAP;
82 p9_debug(P9_DEBUG_9P, "Cache mode: mmap\n");
83 } else if (!strcmp(s, "readahead")) {
84 version = CACHE_SC_READAHEAD;
85 p9_debug(P9_DEBUG_9P, "Cache mode: readahead\n");
86 } else if (!strcmp(s, "none")) {
87 version = CACHE_SC_NONE;
88 p9_debug(P9_DEBUG_9P, "Cache mode: none\n");
89 } else if (kstrtoint(s, 0, &version) != 0) {
90 version = -EINVAL;
91 pr_info("Unknown Cache mode or invalid value %s\n", s);
92 }
93 return version;
94}
95
96/*
97 * Display the mount options in /proc/mounts.
98 */
99int v9fs_show_options(struct seq_file *m, struct dentry *root)
100{
101 struct v9fs_session_info *v9ses = root->d_sb->s_fs_info;
102
103 if (v9ses->debug)
104 seq_printf(m, ",debug=%x", v9ses->debug);
105 if (!uid_eq(v9ses->dfltuid, V9FS_DEFUID))
106 seq_printf(m, ",dfltuid=%u",
107 from_kuid_munged(&init_user_ns, v9ses->dfltuid));
108 if (!gid_eq(v9ses->dfltgid, V9FS_DEFGID))
109 seq_printf(m, ",dfltgid=%u",
110 from_kgid_munged(&init_user_ns, v9ses->dfltgid));
111 if (v9ses->afid != ~0)
112 seq_printf(m, ",afid=%u", v9ses->afid);
113 if (strcmp(v9ses->uname, V9FS_DEFUSER) != 0)
114 seq_printf(m, ",uname=%s", v9ses->uname);
115 if (strcmp(v9ses->aname, V9FS_DEFANAME) != 0)
116 seq_printf(m, ",aname=%s", v9ses->aname);
117 if (v9ses->nodev)
118 seq_puts(m, ",nodevmap");
119 if (v9ses->cache)
120 seq_printf(m, ",cache=%x", v9ses->cache);
121#ifdef CONFIG_9P_FSCACHE
122 if (v9ses->cachetag && (v9ses->cache & CACHE_FSCACHE))
123 seq_printf(m, ",cachetag=%s", v9ses->cachetag);
124#endif
125
126 switch (v9ses->flags & V9FS_ACCESS_MASK) {
127 case V9FS_ACCESS_USER:
128 seq_puts(m, ",access=user");
129 break;
130 case V9FS_ACCESS_ANY:
131 seq_puts(m, ",access=any");
132 break;
133 case V9FS_ACCESS_CLIENT:
134 seq_puts(m, ",access=client");
135 break;
136 case V9FS_ACCESS_SINGLE:
137 seq_printf(m, ",access=%u",
138 from_kuid_munged(&init_user_ns, v9ses->uid));
139 break;
140 }
141
142 if (v9ses->flags & V9FS_IGNORE_QV)
143 seq_puts(m, ",ignoreqv");
144 if (v9ses->flags & V9FS_DIRECT_IO)
145 seq_puts(m, ",directio");
146 if (v9ses->flags & V9FS_POSIX_ACL)
147 seq_puts(m, ",posixacl");
148
149 if (v9ses->flags & V9FS_NO_XATTR)
150 seq_puts(m, ",noxattr");
151
152 return p9_show_client_options(m, v9ses->clnt);
153}
154
155/**
156 * v9fs_parse_options - parse mount options into session structure
157 * @v9ses: existing v9fs session information
158 * @opts: The mount option string
159 *
160 * Return 0 upon success, -ERRNO upon failure.
161 */
162
163static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
164{
165 char *options, *tmp_options;
166 substring_t args[MAX_OPT_ARGS];
167 char *p;
168 int option = 0;
169 char *s;
170 int ret = 0;
171
172 /* setup defaults */
173 v9ses->afid = ~0;
174 v9ses->debug = 0;
175 v9ses->cache = CACHE_NONE;
176#ifdef CONFIG_9P_FSCACHE
177 v9ses->cachetag = NULL;
178#endif
179 v9ses->session_lock_timeout = P9_LOCK_TIMEOUT;
180
181 if (!opts)
182 return 0;
183
184 tmp_options = kstrdup(opts, GFP_KERNEL);
185 if (!tmp_options) {
186 ret = -ENOMEM;
187 goto fail_option_alloc;
188 }
189 options = tmp_options;
190
191 while ((p = strsep(&options, ",")) != NULL) {
192 int token, r;
193
194 if (!*p)
195 continue;
196
197 token = match_token(p, tokens, args);
198 switch (token) {
199 case Opt_debug:
200 r = match_int(&args[0], &option);
201 if (r < 0) {
202 p9_debug(P9_DEBUG_ERROR,
203 "integer field, but no integer?\n");
204 ret = r;
205 } else {
206 v9ses->debug = option;
207#ifdef CONFIG_NET_9P_DEBUG
208 p9_debug_level = option;
209#endif
210 }
211 break;
212
213 case Opt_dfltuid:
214 r = match_int(&args[0], &option);
215 if (r < 0) {
216 p9_debug(P9_DEBUG_ERROR,
217 "integer field, but no integer?\n");
218 ret = r;
219 continue;
220 }
221 v9ses->dfltuid = make_kuid(current_user_ns(), option);
222 if (!uid_valid(v9ses->dfltuid)) {
223 p9_debug(P9_DEBUG_ERROR,
224 "uid field, but not a uid?\n");
225 ret = -EINVAL;
226 }
227 break;
228 case Opt_dfltgid:
229 r = match_int(&args[0], &option);
230 if (r < 0) {
231 p9_debug(P9_DEBUG_ERROR,
232 "integer field, but no integer?\n");
233 ret = r;
234 continue;
235 }
236 v9ses->dfltgid = make_kgid(current_user_ns(), option);
237 if (!gid_valid(v9ses->dfltgid)) {
238 p9_debug(P9_DEBUG_ERROR,
239 "gid field, but not a gid?\n");
240 ret = -EINVAL;
241 }
242 break;
243 case Opt_afid:
244 r = match_int(&args[0], &option);
245 if (r < 0) {
246 p9_debug(P9_DEBUG_ERROR,
247 "integer field, but no integer?\n");
248 ret = r;
249 } else {
250 v9ses->afid = option;
251 }
252 break;
253 case Opt_uname:
254 kfree(v9ses->uname);
255 v9ses->uname = match_strdup(&args[0]);
256 if (!v9ses->uname) {
257 ret = -ENOMEM;
258 goto free_and_return;
259 }
260 break;
261 case Opt_remotename:
262 kfree(v9ses->aname);
263 v9ses->aname = match_strdup(&args[0]);
264 if (!v9ses->aname) {
265 ret = -ENOMEM;
266 goto free_and_return;
267 }
268 break;
269 case Opt_nodevmap:
270 v9ses->nodev = 1;
271 break;
272 case Opt_noxattr:
273 v9ses->flags |= V9FS_NO_XATTR;
274 break;
275 case Opt_directio:
276 v9ses->flags |= V9FS_DIRECT_IO;
277 break;
278 case Opt_ignoreqv:
279 v9ses->flags |= V9FS_IGNORE_QV;
280 break;
281 case Opt_cachetag:
282#ifdef CONFIG_9P_FSCACHE
283 kfree(v9ses->cachetag);
284 v9ses->cachetag = match_strdup(&args[0]);
285 if (!v9ses->cachetag) {
286 ret = -ENOMEM;
287 goto free_and_return;
288 }
289#endif
290 break;
291 case Opt_cache:
292 s = match_strdup(&args[0]);
293 if (!s) {
294 ret = -ENOMEM;
295 p9_debug(P9_DEBUG_ERROR,
296 "problem allocating copy of cache arg\n");
297 goto free_and_return;
298 }
299 r = get_cache_mode(s);
300 if (r < 0)
301 ret = r;
302 else
303 v9ses->cache = r;
304
305 kfree(s);
306 break;
307
308 case Opt_access:
309 s = match_strdup(&args[0]);
310 if (!s) {
311 ret = -ENOMEM;
312 p9_debug(P9_DEBUG_ERROR,
313 "problem allocating copy of access arg\n");
314 goto free_and_return;
315 }
316
317 v9ses->flags &= ~V9FS_ACCESS_MASK;
318 if (strcmp(s, "user") == 0)
319 v9ses->flags |= V9FS_ACCESS_USER;
320 else if (strcmp(s, "any") == 0)
321 v9ses->flags |= V9FS_ACCESS_ANY;
322 else if (strcmp(s, "client") == 0) {
323 v9ses->flags |= V9FS_ACCESS_CLIENT;
324 } else {
325 uid_t uid;
326
327 v9ses->flags |= V9FS_ACCESS_SINGLE;
328 r = kstrtouint(s, 10, &uid);
329 if (r) {
330 ret = r;
331 pr_info("Unknown access argument %s: %d\n",
332 s, r);
333 kfree(s);
334 continue;
335 }
336 v9ses->uid = make_kuid(current_user_ns(), uid);
337 if (!uid_valid(v9ses->uid)) {
338 ret = -EINVAL;
339 pr_info("Unknown uid %s\n", s);
340 }
341 }
342
343 kfree(s);
344 break;
345
346 case Opt_posixacl:
347#ifdef CONFIG_9P_FS_POSIX_ACL
348 v9ses->flags |= V9FS_POSIX_ACL;
349#else
350 p9_debug(P9_DEBUG_ERROR,
351 "Not defined CONFIG_9P_FS_POSIX_ACL. Ignoring posixacl option\n");
352#endif
353 break;
354
355 case Opt_locktimeout:
356 r = match_int(&args[0], &option);
357 if (r < 0) {
358 p9_debug(P9_DEBUG_ERROR,
359 "integer field, but no integer?\n");
360 ret = r;
361 continue;
362 }
363 if (option < 1) {
364 p9_debug(P9_DEBUG_ERROR,
365 "locktimeout must be a greater than zero integer.\n");
366 ret = -EINVAL;
367 continue;
368 }
369 v9ses->session_lock_timeout = (long)option * HZ;
370 break;
371
372 default:
373 continue;
374 }
375 }
376
377free_and_return:
378 kfree(tmp_options);
379fail_option_alloc:
380 return ret;
381}
382
383/**
384 * v9fs_session_init - initialize session
385 * @v9ses: session information structure
386 * @dev_name: device being mounted
387 * @data: options
388 *
389 */
390
391struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
392 const char *dev_name, char *data)
393{
394 struct p9_fid *fid;
395 int rc = -ENOMEM;
396
397 v9ses->uname = kstrdup(V9FS_DEFUSER, GFP_KERNEL);
398 if (!v9ses->uname)
399 goto err_names;
400
401 v9ses->aname = kstrdup(V9FS_DEFANAME, GFP_KERNEL);
402 if (!v9ses->aname)
403 goto err_names;
404 init_rwsem(&v9ses->rename_sem);
405
406 v9ses->uid = INVALID_UID;
407 v9ses->dfltuid = V9FS_DEFUID;
408 v9ses->dfltgid = V9FS_DEFGID;
409
410 v9ses->clnt = p9_client_create(dev_name, data);
411 if (IS_ERR(v9ses->clnt)) {
412 rc = PTR_ERR(v9ses->clnt);
413 p9_debug(P9_DEBUG_ERROR, "problem initializing 9p client\n");
414 goto err_names;
415 }
416
417 v9ses->flags = V9FS_ACCESS_USER;
418
419 if (p9_is_proto_dotl(v9ses->clnt)) {
420 v9ses->flags = V9FS_ACCESS_CLIENT;
421 v9ses->flags |= V9FS_PROTO_2000L;
422 } else if (p9_is_proto_dotu(v9ses->clnt)) {
423 v9ses->flags |= V9FS_PROTO_2000U;
424 }
425
426 rc = v9fs_parse_options(v9ses, data);
427 if (rc < 0)
428 goto err_clnt;
429
430 v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;
431
432 if (!v9fs_proto_dotl(v9ses) &&
433 ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
434 /*
435 * We support ACCESS_CLIENT only for dotl.
436 * Fall back to ACCESS_USER
437 */
438 v9ses->flags &= ~V9FS_ACCESS_MASK;
439 v9ses->flags |= V9FS_ACCESS_USER;
440 }
441 /*FIXME !! */
442 /* for legacy mode, fall back to V9FS_ACCESS_ANY */
443 if (!(v9fs_proto_dotu(v9ses) || v9fs_proto_dotl(v9ses)) &&
444 ((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {
445
446 v9ses->flags &= ~V9FS_ACCESS_MASK;
447 v9ses->flags |= V9FS_ACCESS_ANY;
448 v9ses->uid = INVALID_UID;
449 }
450 if (!v9fs_proto_dotl(v9ses) ||
451 !((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
452 /*
453 * We support ACL checks on clinet only if the protocol is
454 * 9P2000.L and access is V9FS_ACCESS_CLIENT.
455 */
456 v9ses->flags &= ~V9FS_ACL_MASK;
457 }
458
459 fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, INVALID_UID,
460 v9ses->aname);
461 if (IS_ERR(fid)) {
462 rc = PTR_ERR(fid);
463 p9_debug(P9_DEBUG_ERROR, "cannot attach\n");
464 goto err_clnt;
465 }
466
467 if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
468 fid->uid = v9ses->uid;
469 else
470 fid->uid = INVALID_UID;
471
472#ifdef CONFIG_9P_FSCACHE
473 /* register the session for caching */
474 if (v9ses->cache & CACHE_FSCACHE) {
475 rc = v9fs_cache_session_get_cookie(v9ses, dev_name);
476 if (rc < 0)
477 goto err_clnt;
478 }
479#endif
480 spin_lock(&v9fs_sessionlist_lock);
481 list_add(&v9ses->slist, &v9fs_sessionlist);
482 spin_unlock(&v9fs_sessionlist_lock);
483
484 return fid;
485
486err_clnt:
487#ifdef CONFIG_9P_FSCACHE
488 kfree(v9ses->cachetag);
489#endif
490 p9_client_destroy(v9ses->clnt);
491err_names:
492 kfree(v9ses->uname);
493 kfree(v9ses->aname);
494 return ERR_PTR(rc);
495}
496
497/**
498 * v9fs_session_close - shutdown a session
499 * @v9ses: session information structure
500 *
501 */
502
503void v9fs_session_close(struct v9fs_session_info *v9ses)
504{
505 if (v9ses->clnt) {
506 p9_client_destroy(v9ses->clnt);
507 v9ses->clnt = NULL;
508 }
509
510#ifdef CONFIG_9P_FSCACHE
511 fscache_relinquish_volume(v9fs_session_cache(v9ses), NULL, false);
512 kfree(v9ses->cachetag);
513#endif
514 kfree(v9ses->uname);
515 kfree(v9ses->aname);
516
517 spin_lock(&v9fs_sessionlist_lock);
518 list_del(&v9ses->slist);
519 spin_unlock(&v9fs_sessionlist_lock);
520}
521
522/**
523 * v9fs_session_cancel - terminate a session
524 * @v9ses: session to terminate
525 *
526 * mark transport as disconnected and cancel all pending requests.
527 */
528
529void v9fs_session_cancel(struct v9fs_session_info *v9ses)
530{
531 p9_debug(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
532 p9_client_disconnect(v9ses->clnt);
533}
534
535/**
536 * v9fs_session_begin_cancel - Begin terminate of a session
537 * @v9ses: session to terminate
538 *
539 * After this call we don't allow any request other than clunk.
540 */
541
542void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses)
543{
544 p9_debug(P9_DEBUG_ERROR, "begin cancel session %p\n", v9ses);
545 p9_client_begin_disconnect(v9ses->clnt);
546}
547
548static struct kobject *v9fs_kobj;
549
550#ifdef CONFIG_9P_FSCACHE
551/*
552 * List caches associated with a session
553 */
554static ssize_t caches_show(struct kobject *kobj,
555 struct kobj_attribute *attr,
556 char *buf)
557{
558 ssize_t n = 0, count = 0, limit = PAGE_SIZE;
559 struct v9fs_session_info *v9ses;
560
561 spin_lock(&v9fs_sessionlist_lock);
562 list_for_each_entry(v9ses, &v9fs_sessionlist, slist) {
563 if (v9ses->cachetag) {
564 n = snprintf(buf, limit, "%s\n", v9ses->cachetag);
565 if (n < 0) {
566 count = n;
567 break;
568 }
569
570 count += n;
571 limit -= n;
572 }
573 }
574
575 spin_unlock(&v9fs_sessionlist_lock);
576 return count;
577}
578
579static struct kobj_attribute v9fs_attr_cache = __ATTR_RO(caches);
580#endif /* CONFIG_9P_FSCACHE */
581
582static struct attribute *v9fs_attrs[] = {
583#ifdef CONFIG_9P_FSCACHE
584 &v9fs_attr_cache.attr,
585#endif
586 NULL,
587};
588
589static const struct attribute_group v9fs_attr_group = {
590 .attrs = v9fs_attrs,
591};
592
593/**
594 * v9fs_sysfs_init - Initialize the v9fs sysfs interface
595 *
596 */
597
598static int __init v9fs_sysfs_init(void)
599{
600 v9fs_kobj = kobject_create_and_add("9p", fs_kobj);
601 if (!v9fs_kobj)
602 return -ENOMEM;
603
604 if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) {
605 kobject_put(v9fs_kobj);
606 return -ENOMEM;
607 }
608
609 return 0;
610}
611
612/**
613 * v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface
614 *
615 */
616
617static void v9fs_sysfs_cleanup(void)
618{
619 sysfs_remove_group(v9fs_kobj, &v9fs_attr_group);
620 kobject_put(v9fs_kobj);
621}
622
623static void v9fs_inode_init_once(void *foo)
624{
625 struct v9fs_inode *v9inode = (struct v9fs_inode *)foo;
626
627 memset(&v9inode->qid, 0, sizeof(v9inode->qid));
628 inode_init_once(&v9inode->netfs.inode);
629}
630
631/**
632 * v9fs_init_inode_cache - initialize a cache for 9P
633 * Returns 0 on success.
634 */
635static int v9fs_init_inode_cache(void)
636{
637 v9fs_inode_cache = kmem_cache_create("v9fs_inode_cache",
638 sizeof(struct v9fs_inode),
639 0, (SLAB_RECLAIM_ACCOUNT|
640 SLAB_ACCOUNT),
641 v9fs_inode_init_once);
642 if (!v9fs_inode_cache)
643 return -ENOMEM;
644
645 return 0;
646}
647
648/**
649 * v9fs_destroy_inode_cache - destroy the cache of 9P inode
650 *
651 */
652static void v9fs_destroy_inode_cache(void)
653{
654 /*
655 * Make sure all delayed rcu free inodes are flushed before we
656 * destroy cache.
657 */
658 rcu_barrier();
659 kmem_cache_destroy(v9fs_inode_cache);
660}
661
662static int v9fs_cache_register(void)
663{
664 int ret;
665
666 ret = v9fs_init_inode_cache();
667 if (ret < 0)
668 return ret;
669 return ret;
670}
671
672static void v9fs_cache_unregister(void)
673{
674 v9fs_destroy_inode_cache();
675}
676
677/**
678 * init_v9fs - Initialize module
679 *
680 */
681
682static int __init init_v9fs(void)
683{
684 int err;
685
686 pr_info("Installing v9fs 9p2000 file system support\n");
687 /* TODO: Setup list of registered trasnport modules */
688
689 err = v9fs_cache_register();
690 if (err < 0) {
691 pr_err("Failed to register v9fs for caching\n");
692 return err;
693 }
694
695 err = v9fs_sysfs_init();
696 if (err < 0) {
697 pr_err("Failed to register with sysfs\n");
698 goto out_cache;
699 }
700 err = register_filesystem(&v9fs_fs_type);
701 if (err < 0) {
702 pr_err("Failed to register filesystem\n");
703 goto out_sysfs_cleanup;
704 }
705
706 return 0;
707
708out_sysfs_cleanup:
709 v9fs_sysfs_cleanup();
710
711out_cache:
712 v9fs_cache_unregister();
713
714 return err;
715}
716
717/**
718 * exit_v9fs - shutdown module
719 *
720 */
721
722static void __exit exit_v9fs(void)
723{
724 v9fs_sysfs_cleanup();
725 v9fs_cache_unregister();
726 unregister_filesystem(&v9fs_fs_type);
727}
728
729module_init(init_v9fs)
730module_exit(exit_v9fs)
731
732MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
733MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
734MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
735MODULE_DESCRIPTION("9P Client File System");
736MODULE_LICENSE("GPL");