9p: add 9P2000.L statfs operation
[linux-2.6.git] / net / 9p / client.c
1 /*
2  * net/9p/clnt.c
3  *
4  * 9P Client
5  *
6  *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
7  *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
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 #include <linux/module.h>
27 #include <linux/errno.h>
28 #include <linux/fs.h>
29 #include <linux/poll.h>
30 #include <linux/idr.h>
31 #include <linux/mutex.h>
32 #include <linux/slab.h>
33 #include <linux/sched.h>
34 #include <linux/uaccess.h>
35 #include <net/9p/9p.h>
36 #include <linux/parser.h>
37 #include <net/9p/client.h>
38 #include <net/9p/transport.h>
39 #include "protocol.h"
40
41 /*
42   * Client Option Parsing (code inspired by NFS code)
43   *  - a little lazy - parse all client options
44   */
45
46 enum {
47         Opt_msize,
48         Opt_trans,
49         Opt_legacy,
50         Opt_version,
51         Opt_err,
52 };
53
54 static const match_table_t tokens = {
55         {Opt_msize, "msize=%u"},
56         {Opt_legacy, "noextend"},
57         {Opt_trans, "trans=%s"},
58         {Opt_version, "version=%s"},
59         {Opt_err, NULL},
60 };
61
62 inline int p9_is_proto_dotl(struct p9_client *clnt)
63 {
64         return (clnt->proto_version == p9_proto_2000L);
65 }
66 EXPORT_SYMBOL(p9_is_proto_dotl);
67
68 inline int p9_is_proto_dotu(struct p9_client *clnt)
69 {
70         return (clnt->proto_version == p9_proto_2000u);
71 }
72 EXPORT_SYMBOL(p9_is_proto_dotu);
73
74 /* Interpret mount option for protocol version */
75 static int get_protocol_version(const substring_t *name)
76 {
77         int version = -EINVAL;
78
79         if (!strncmp("9p2000", name->from, name->to-name->from)) {
80                 version = p9_proto_legacy;
81                 P9_DPRINTK(P9_DEBUG_9P, "Protocol version: Legacy\n");
82         } else if (!strncmp("9p2000.u", name->from, name->to-name->from)) {
83                 version = p9_proto_2000u;
84                 P9_DPRINTK(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
85         } else if (!strncmp("9p2000.L", name->from, name->to-name->from)) {
86                 version = p9_proto_2000L;
87                 P9_DPRINTK(P9_DEBUG_9P, "Protocol version: 9P2000.L\n");
88         } else {
89                 P9_DPRINTK(P9_DEBUG_ERROR, "Unknown protocol version %s. ",
90                                                         name->from);
91         }
92         return version;
93 }
94
95 static struct p9_req_t *
96 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
97
98 /**
99  * parse_options - parse mount options into client structure
100  * @opts: options string passed from mount
101  * @clnt: existing v9fs client information
102  *
103  * Return 0 upon success, -ERRNO upon failure
104  */
105
106 static int parse_opts(char *opts, struct p9_client *clnt)
107 {
108         char *options, *tmp_options;
109         char *p;
110         substring_t args[MAX_OPT_ARGS];
111         int option;
112         int ret = 0;
113
114         clnt->proto_version = p9_proto_2000u;
115         clnt->msize = 8192;
116
117         if (!opts)
118                 return 0;
119
120         tmp_options = kstrdup(opts, GFP_KERNEL);
121         if (!tmp_options) {
122                 P9_DPRINTK(P9_DEBUG_ERROR,
123                                 "failed to allocate copy of option string\n");
124                 return -ENOMEM;
125         }
126         options = tmp_options;
127
128         while ((p = strsep(&options, ",")) != NULL) {
129                 int token;
130                 if (!*p)
131                         continue;
132                 token = match_token(p, tokens, args);
133                 if (token < Opt_trans) {
134                         int r = match_int(&args[0], &option);
135                         if (r < 0) {
136                                 P9_DPRINTK(P9_DEBUG_ERROR,
137                                         "integer field, but no integer?\n");
138                                 ret = r;
139                                 continue;
140                         }
141                 }
142                 switch (token) {
143                 case Opt_msize:
144                         clnt->msize = option;
145                         break;
146                 case Opt_trans:
147                         clnt->trans_mod = v9fs_get_trans_by_name(&args[0]);
148                         if(clnt->trans_mod == NULL) {
149                                 P9_DPRINTK(P9_DEBUG_ERROR,
150                                    "Could not find request transport: %s\n",
151                                    (char *) &args[0]);
152                                 ret = -EINVAL;
153                                 goto free_and_return;
154                         }
155                         break;
156                 case Opt_legacy:
157                         clnt->proto_version = p9_proto_legacy;
158                         break;
159                 case Opt_version:
160                         ret = get_protocol_version(&args[0]);
161                         if (ret == -EINVAL)
162                                 goto free_and_return;
163                         clnt->proto_version = ret;
164                         break;
165                 default:
166                         continue;
167                 }
168         }
169
170 free_and_return:
171         kfree(tmp_options);
172         return ret;
173 }
174
175 /**
176  * p9_tag_alloc - lookup/allocate a request by tag
177  * @c: client session to lookup tag within
178  * @tag: numeric id for transaction
179  *
180  * this is a simple array lookup, but will grow the
181  * request_slots as necessary to accomodate transaction
182  * ids which did not previously have a slot.
183  *
184  * this code relies on the client spinlock to manage locks, its
185  * possible we should switch to something else, but I'd rather
186  * stick with something low-overhead for the common case.
187  *
188  */
189
190 static struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag)
191 {
192         unsigned long flags;
193         int row, col;
194         struct p9_req_t *req;
195
196         /* This looks up the original request by tag so we know which
197          * buffer to read the data into */
198         tag++;
199
200         if (tag >= c->max_tag) {
201                 spin_lock_irqsave(&c->lock, flags);
202                 /* check again since original check was outside of lock */
203                 while (tag >= c->max_tag) {
204                         row = (tag / P9_ROW_MAXTAG);
205                         c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
206                                         sizeof(struct p9_req_t), GFP_ATOMIC);
207
208                         if (!c->reqs[row]) {
209                                 printk(KERN_ERR "Couldn't grow tag array\n");
210                                 spin_unlock_irqrestore(&c->lock, flags);
211                                 return ERR_PTR(-ENOMEM);
212                         }
213                         for (col = 0; col < P9_ROW_MAXTAG; col++) {
214                                 c->reqs[row][col].status = REQ_STATUS_IDLE;
215                                 c->reqs[row][col].tc = NULL;
216                         }
217                         c->max_tag += P9_ROW_MAXTAG;
218                 }
219                 spin_unlock_irqrestore(&c->lock, flags);
220         }
221         row = tag / P9_ROW_MAXTAG;
222         col = tag % P9_ROW_MAXTAG;
223
224         req = &c->reqs[row][col];
225         if (!req->tc) {
226                 req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_KERNEL);
227                 if (!req->wq) {
228                         printk(KERN_ERR "Couldn't grow tag array\n");
229                         return ERR_PTR(-ENOMEM);
230                 }
231                 init_waitqueue_head(req->wq);
232                 req->tc = kmalloc(sizeof(struct p9_fcall)+c->msize,
233                                                                 GFP_KERNEL);
234                 req->rc = kmalloc(sizeof(struct p9_fcall)+c->msize,
235                                                                 GFP_KERNEL);
236                 if ((!req->tc) || (!req->rc)) {
237                         printk(KERN_ERR "Couldn't grow tag array\n");
238                         kfree(req->tc);
239                         kfree(req->rc);
240                         kfree(req->wq);
241                         req->tc = req->rc = NULL;
242                         req->wq = NULL;
243                         return ERR_PTR(-ENOMEM);
244                 }
245                 req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
246                 req->tc->capacity = c->msize;
247                 req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall);
248                 req->rc->capacity = c->msize;
249         }
250
251         p9pdu_reset(req->tc);
252         p9pdu_reset(req->rc);
253
254         req->tc->tag = tag-1;
255         req->status = REQ_STATUS_ALLOC;
256
257         return &c->reqs[row][col];
258 }
259
260 /**
261  * p9_tag_lookup - lookup a request by tag
262  * @c: client session to lookup tag within
263  * @tag: numeric id for transaction
264  *
265  */
266
267 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
268 {
269         int row, col;
270
271         /* This looks up the original request by tag so we know which
272          * buffer to read the data into */
273         tag++;
274
275         BUG_ON(tag >= c->max_tag);
276
277         row = tag / P9_ROW_MAXTAG;
278         col = tag % P9_ROW_MAXTAG;
279
280         return &c->reqs[row][col];
281 }
282 EXPORT_SYMBOL(p9_tag_lookup);
283
284 /**
285  * p9_tag_init - setup tags structure and contents
286  * @c:  v9fs client struct
287  *
288  * This initializes the tags structure for each client instance.
289  *
290  */
291
292 static int p9_tag_init(struct p9_client *c)
293 {
294         int err = 0;
295
296         c->tagpool = p9_idpool_create();
297         if (IS_ERR(c->tagpool)) {
298                 err = PTR_ERR(c->tagpool);
299                 c->tagpool = NULL;
300                 goto error;
301         }
302
303         p9_idpool_get(c->tagpool); /* reserve tag 0 */
304
305         c->max_tag = 0;
306 error:
307         return err;
308 }
309
310 /**
311  * p9_tag_cleanup - cleans up tags structure and reclaims resources
312  * @c:  v9fs client struct
313  *
314  * This frees resources associated with the tags structure
315  *
316  */
317 static void p9_tag_cleanup(struct p9_client *c)
318 {
319         int row, col;
320
321         /* check to insure all requests are idle */
322         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
323                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
324                         if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
325                                 P9_DPRINTK(P9_DEBUG_MUX,
326                                   "Attempting to cleanup non-free tag %d,%d\n",
327                                   row, col);
328                                 /* TODO: delay execution of cleanup */
329                                 return;
330                         }
331                 }
332         }
333
334         if (c->tagpool)
335                 p9_idpool_destroy(c->tagpool);
336
337         /* free requests associated with tags */
338         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
339                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
340                         kfree(c->reqs[row][col].wq);
341                         kfree(c->reqs[row][col].tc);
342                         kfree(c->reqs[row][col].rc);
343                 }
344                 kfree(c->reqs[row]);
345         }
346         c->max_tag = 0;
347 }
348
349 /**
350  * p9_free_req - free a request and clean-up as necessary
351  * c: client state
352  * r: request to release
353  *
354  */
355
356 static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
357 {
358         int tag = r->tc->tag;
359         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
360
361         r->status = REQ_STATUS_IDLE;
362         if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
363                 p9_idpool_put(tag, c->tagpool);
364 }
365
366 /**
367  * p9_client_cb - call back from transport to client
368  * c: client state
369  * req: request received
370  *
371  */
372 void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
373 {
374         P9_DPRINTK(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
375         wake_up(req->wq);
376         P9_DPRINTK(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
377 }
378 EXPORT_SYMBOL(p9_client_cb);
379
380 /**
381  * p9_parse_header - parse header arguments out of a packet
382  * @pdu: packet to parse
383  * @size: size of packet
384  * @type: type of request
385  * @tag: tag of packet
386  * @rewind: set if we need to rewind offset afterwards
387  */
388
389 int
390 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
391                                                                 int rewind)
392 {
393         int8_t r_type;
394         int16_t r_tag;
395         int32_t r_size;
396         int offset = pdu->offset;
397         int err;
398
399         pdu->offset = 0;
400         if (pdu->size == 0)
401                 pdu->size = 7;
402
403         err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
404         if (err)
405                 goto rewind_and_exit;
406
407         pdu->size = r_size;
408         pdu->id = r_type;
409         pdu->tag = r_tag;
410
411         P9_DPRINTK(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n", pdu->size,
412                                                         pdu->id, pdu->tag);
413
414         if (type)
415                 *type = r_type;
416         if (tag)
417                 *tag = r_tag;
418         if (size)
419                 *size = r_size;
420
421
422 rewind_and_exit:
423         if (rewind)
424                 pdu->offset = offset;
425         return err;
426 }
427 EXPORT_SYMBOL(p9_parse_header);
428
429 /**
430  * p9_check_errors - check 9p packet for error return and process it
431  * @c: current client instance
432  * @req: request to parse and check for error conditions
433  *
434  * returns error code if one is discovered, otherwise returns 0
435  *
436  * this will have to be more complicated if we have multiple
437  * error packet types
438  */
439
440 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
441 {
442         int8_t type;
443         int err;
444
445         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
446         if (err) {
447                 P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
448                 return err;
449         }
450
451         if (type == P9_RERROR) {
452                 int ecode;
453                 char *ename;
454
455                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
456                                                         &ename, &ecode);
457                 if (err) {
458                         P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n",
459                                                                         err);
460                         return err;
461                 }
462
463                 if (p9_is_proto_dotu(c))
464                         err = -ecode;
465
466                 if (!err || !IS_ERR_VALUE(err))
467                         err = p9_errstr2errno(ename, strlen(ename));
468
469                 P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
470
471                 kfree(ename);
472         } else
473                 err = 0;
474
475         return err;
476 }
477
478 /**
479  * p9_client_flush - flush (cancel) a request
480  * @c: client state
481  * @oldreq: request to cancel
482  *
483  * This sents a flush for a particular requests and links
484  * the flush request to the original request.  The current
485  * code only supports a single flush request although the protocol
486  * allows for multiple flush requests to be sent for a single request.
487  *
488  */
489
490 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
491 {
492         struct p9_req_t *req;
493         int16_t oldtag;
494         int err;
495
496         err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
497         if (err)
498                 return err;
499
500         P9_DPRINTK(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
501
502         req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
503         if (IS_ERR(req))
504                 return PTR_ERR(req);
505
506
507         /* if we haven't received a response for oldreq,
508            remove it from the list. */
509         spin_lock(&c->lock);
510         if (oldreq->status == REQ_STATUS_FLSH)
511                 list_del(&oldreq->req_list);
512         spin_unlock(&c->lock);
513
514         p9_free_req(c, req);
515         return 0;
516 }
517
518 /**
519  * p9_client_rpc - issue a request and wait for a response
520  * @c: client session
521  * @type: type of request
522  * @fmt: protocol format string (see protocol.c)
523  *
524  * Returns request structure (which client must free using p9_free_req)
525  */
526
527 static struct p9_req_t *
528 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
529 {
530         va_list ap;
531         int tag, err;
532         struct p9_req_t *req;
533         unsigned long flags;
534         int sigpending;
535
536         P9_DPRINTK(P9_DEBUG_MUX, "client %p op %d\n", c, type);
537
538         /* we allow for any status other than disconnected */
539         if (c->status == Disconnected)
540                 return ERR_PTR(-EIO);
541
542         /* if status is begin_disconnected we allow only clunk request */
543         if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
544                 return ERR_PTR(-EIO);
545
546         if (signal_pending(current)) {
547                 sigpending = 1;
548                 clear_thread_flag(TIF_SIGPENDING);
549         } else
550                 sigpending = 0;
551
552         tag = P9_NOTAG;
553         if (type != P9_TVERSION) {
554                 tag = p9_idpool_get(c->tagpool);
555                 if (tag < 0)
556                         return ERR_PTR(-ENOMEM);
557         }
558
559         req = p9_tag_alloc(c, tag);
560         if (IS_ERR(req))
561                 return req;
562
563         /* marshall the data */
564         p9pdu_prepare(req->tc, tag, type);
565         va_start(ap, fmt);
566         err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
567         va_end(ap);
568         p9pdu_finalize(req->tc);
569
570         err = c->trans_mod->request(c, req);
571         if (err < 0) {
572                 c->status = Disconnected;
573                 goto reterr;
574         }
575
576         P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d\n", req->wq, tag);
577         err = wait_event_interruptible(*req->wq,
578                                                 req->status >= REQ_STATUS_RCVD);
579         P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d returned %d\n",
580                                                 req->wq, tag, err);
581
582         if (req->status == REQ_STATUS_ERROR) {
583                 P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
584                 err = req->t_err;
585         }
586
587         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
588                 P9_DPRINTK(P9_DEBUG_MUX, "flushing\n");
589                 sigpending = 1;
590                 clear_thread_flag(TIF_SIGPENDING);
591
592                 if (c->trans_mod->cancel(c, req))
593                         p9_client_flush(c, req);
594
595                 /* if we received the response anyway, don't signal error */
596                 if (req->status == REQ_STATUS_RCVD)
597                         err = 0;
598         }
599
600         if (sigpending) {
601                 spin_lock_irqsave(&current->sighand->siglock, flags);
602                 recalc_sigpending();
603                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
604         }
605
606         if (err < 0)
607                 goto reterr;
608
609         err = p9_check_errors(c, req);
610         if (!err) {
611                 P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d\n", c, type);
612                 return req;
613         }
614
615 reterr:
616         P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d error: %d\n", c, type,
617                                                                         err);
618         p9_free_req(c, req);
619         return ERR_PTR(err);
620 }
621
622 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
623 {
624         int ret;
625         struct p9_fid *fid;
626         unsigned long flags;
627
628         P9_DPRINTK(P9_DEBUG_FID, "clnt %p\n", clnt);
629         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
630         if (!fid)
631                 return ERR_PTR(-ENOMEM);
632
633         ret = p9_idpool_get(clnt->fidpool);
634         if (ret < 0) {
635                 ret = -ENOSPC;
636                 goto error;
637         }
638         fid->fid = ret;
639
640         memset(&fid->qid, 0, sizeof(struct p9_qid));
641         fid->mode = -1;
642         fid->uid = current_fsuid();
643         fid->clnt = clnt;
644         fid->rdir = NULL;
645         spin_lock_irqsave(&clnt->lock, flags);
646         list_add(&fid->flist, &clnt->fidlist);
647         spin_unlock_irqrestore(&clnt->lock, flags);
648
649         return fid;
650
651 error:
652         kfree(fid);
653         return ERR_PTR(ret);
654 }
655
656 static void p9_fid_destroy(struct p9_fid *fid)
657 {
658         struct p9_client *clnt;
659         unsigned long flags;
660
661         P9_DPRINTK(P9_DEBUG_FID, "fid %d\n", fid->fid);
662         clnt = fid->clnt;
663         p9_idpool_put(fid->fid, clnt->fidpool);
664         spin_lock_irqsave(&clnt->lock, flags);
665         list_del(&fid->flist);
666         spin_unlock_irqrestore(&clnt->lock, flags);
667         kfree(fid->rdir);
668         kfree(fid);
669 }
670
671 int p9_client_version(struct p9_client *c)
672 {
673         int err = 0;
674         struct p9_req_t *req;
675         char *version;
676         int msize;
677
678         P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
679                                                 c->msize, c->proto_version);
680
681         switch (c->proto_version) {
682         case p9_proto_2000L:
683                 req = p9_client_rpc(c, P9_TVERSION, "ds",
684                                         c->msize, "9P2000.L");
685                 break;
686         case p9_proto_2000u:
687                 req = p9_client_rpc(c, P9_TVERSION, "ds",
688                                         c->msize, "9P2000.u");
689                 break;
690         case p9_proto_legacy:
691                 req = p9_client_rpc(c, P9_TVERSION, "ds",
692                                         c->msize, "9P2000");
693                 break;
694         default:
695                 return -EINVAL;
696                 break;
697         }
698
699         if (IS_ERR(req))
700                 return PTR_ERR(req);
701
702         err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
703         if (err) {
704                 P9_DPRINTK(P9_DEBUG_9P, "version error %d\n", err);
705                 p9pdu_dump(1, req->rc);
706                 goto error;
707         }
708
709         P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
710         if (!strncmp(version, "9P2000.L", 8))
711                 c->proto_version = p9_proto_2000L;
712         else if (!strncmp(version, "9P2000.u", 8))
713                 c->proto_version = p9_proto_2000u;
714         else if (!strncmp(version, "9P2000", 6))
715                 c->proto_version = p9_proto_legacy;
716         else {
717                 err = -EREMOTEIO;
718                 goto error;
719         }
720
721         if (msize < c->msize)
722                 c->msize = msize;
723
724 error:
725         kfree(version);
726         p9_free_req(c, req);
727
728         return err;
729 }
730 EXPORT_SYMBOL(p9_client_version);
731
732 struct p9_client *p9_client_create(const char *dev_name, char *options)
733 {
734         int err;
735         struct p9_client *clnt;
736
737         err = 0;
738         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
739         if (!clnt)
740                 return ERR_PTR(-ENOMEM);
741
742         clnt->trans_mod = NULL;
743         clnt->trans = NULL;
744         spin_lock_init(&clnt->lock);
745         INIT_LIST_HEAD(&clnt->fidlist);
746
747         p9_tag_init(clnt);
748
749         err = parse_opts(options, clnt);
750         if (err < 0)
751                 goto free_client;
752
753         if (!clnt->trans_mod)
754                 clnt->trans_mod = v9fs_get_default_trans();
755
756         if (clnt->trans_mod == NULL) {
757                 err = -EPROTONOSUPPORT;
758                 P9_DPRINTK(P9_DEBUG_ERROR,
759                                 "No transport defined or default transport\n");
760                 goto free_client;
761         }
762
763         clnt->fidpool = p9_idpool_create();
764         if (IS_ERR(clnt->fidpool)) {
765                 err = PTR_ERR(clnt->fidpool);
766                 clnt->fidpool = NULL;
767                 goto put_trans;
768         }
769
770         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
771                 clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
772
773         err = clnt->trans_mod->create(clnt, dev_name, options);
774         if (err)
775                 goto destroy_fidpool;
776
777         if ((clnt->msize+P9_IOHDRSZ) > clnt->trans_mod->maxsize)
778                 clnt->msize = clnt->trans_mod->maxsize-P9_IOHDRSZ;
779
780         err = p9_client_version(clnt);
781         if (err)
782                 goto close_trans;
783
784         return clnt;
785
786 close_trans:
787         clnt->trans_mod->close(clnt);
788 destroy_fidpool:
789         p9_idpool_destroy(clnt->fidpool);
790 put_trans:
791         v9fs_put_trans(clnt->trans_mod);
792 free_client:
793         kfree(clnt);
794         return ERR_PTR(err);
795 }
796 EXPORT_SYMBOL(p9_client_create);
797
798 void p9_client_destroy(struct p9_client *clnt)
799 {
800         struct p9_fid *fid, *fidptr;
801
802         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p\n", clnt);
803
804         if (clnt->trans_mod)
805                 clnt->trans_mod->close(clnt);
806
807         v9fs_put_trans(clnt->trans_mod);
808
809         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
810                 printk(KERN_INFO "Found fid %d not clunked\n", fid->fid);
811                 p9_fid_destroy(fid);
812         }
813
814         if (clnt->fidpool)
815                 p9_idpool_destroy(clnt->fidpool);
816
817         p9_tag_cleanup(clnt);
818
819         kfree(clnt);
820 }
821 EXPORT_SYMBOL(p9_client_destroy);
822
823 void p9_client_disconnect(struct p9_client *clnt)
824 {
825         P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
826         clnt->status = Disconnected;
827 }
828 EXPORT_SYMBOL(p9_client_disconnect);
829
830 void p9_client_begin_disconnect(struct p9_client *clnt)
831 {
832         P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
833         clnt->status = BeginDisconnect;
834 }
835 EXPORT_SYMBOL(p9_client_begin_disconnect);
836
837 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
838         char *uname, u32 n_uname, char *aname)
839 {
840         int err;
841         struct p9_req_t *req;
842         struct p9_fid *fid;
843         struct p9_qid qid;
844
845         P9_DPRINTK(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
846                                         afid ? afid->fid : -1, uname, aname);
847         err = 0;
848
849         fid = p9_fid_create(clnt);
850         if (IS_ERR(fid)) {
851                 err = PTR_ERR(fid);
852                 fid = NULL;
853                 goto error;
854         }
855
856         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
857                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
858         if (IS_ERR(req)) {
859                 err = PTR_ERR(req);
860                 goto error;
861         }
862
863         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
864         if (err) {
865                 p9pdu_dump(1, req->rc);
866                 p9_free_req(clnt, req);
867                 goto error;
868         }
869
870         P9_DPRINTK(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
871                                         qid.type,
872                                         (unsigned long long)qid.path,
873                                         qid.version);
874
875         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
876
877         p9_free_req(clnt, req);
878         return fid;
879
880 error:
881         if (fid)
882                 p9_fid_destroy(fid);
883         return ERR_PTR(err);
884 }
885 EXPORT_SYMBOL(p9_client_attach);
886
887 struct p9_fid *
888 p9_client_auth(struct p9_client *clnt, char *uname, u32 n_uname, char *aname)
889 {
890         int err;
891         struct p9_req_t *req;
892         struct p9_qid qid;
893         struct p9_fid *afid;
894
895         P9_DPRINTK(P9_DEBUG_9P, ">>> TAUTH uname %s aname %s\n", uname, aname);
896         err = 0;
897
898         afid = p9_fid_create(clnt);
899         if (IS_ERR(afid)) {
900                 err = PTR_ERR(afid);
901                 afid = NULL;
902                 goto error;
903         }
904
905         req = p9_client_rpc(clnt, P9_TAUTH, "dss?d",
906                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
907         if (IS_ERR(req)) {
908                 err = PTR_ERR(req);
909                 goto error;
910         }
911
912         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
913         if (err) {
914                 p9pdu_dump(1, req->rc);
915                 p9_free_req(clnt, req);
916                 goto error;
917         }
918
919         P9_DPRINTK(P9_DEBUG_9P, "<<< RAUTH qid %x.%llx.%x\n",
920                                         qid.type,
921                                         (unsigned long long)qid.path,
922                                         qid.version);
923
924         memmove(&afid->qid, &qid, sizeof(struct p9_qid));
925         p9_free_req(clnt, req);
926         return afid;
927
928 error:
929         if (afid)
930                 p9_fid_destroy(afid);
931         return ERR_PTR(err);
932 }
933 EXPORT_SYMBOL(p9_client_auth);
934
935 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, int nwname, char **wnames,
936         int clone)
937 {
938         int err;
939         struct p9_client *clnt;
940         struct p9_fid *fid;
941         struct p9_qid *wqids;
942         struct p9_req_t *req;
943         int16_t nwqids, count;
944
945         err = 0;
946         clnt = oldfid->clnt;
947         if (clone) {
948                 fid = p9_fid_create(clnt);
949                 if (IS_ERR(fid)) {
950                         err = PTR_ERR(fid);
951                         fid = NULL;
952                         goto error;
953                 }
954
955                 fid->uid = oldfid->uid;
956         } else
957                 fid = oldfid;
958
959
960         P9_DPRINTK(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %d wname[0] %s\n",
961                 oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
962
963         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
964                                                                 nwname, wnames);
965         if (IS_ERR(req)) {
966                 err = PTR_ERR(req);
967                 goto error;
968         }
969
970         err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
971         if (err) {
972                 p9pdu_dump(1, req->rc);
973                 p9_free_req(clnt, req);
974                 goto clunk_fid;
975         }
976         p9_free_req(clnt, req);
977
978         P9_DPRINTK(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
979
980         if (nwqids != nwname) {
981                 err = -ENOENT;
982                 goto clunk_fid;
983         }
984
985         for (count = 0; count < nwqids; count++)
986                 P9_DPRINTK(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
987                         count, wqids[count].type,
988                         (unsigned long long)wqids[count].path,
989                         wqids[count].version);
990
991         if (nwname)
992                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
993         else
994                 fid->qid = oldfid->qid;
995
996         return fid;
997
998 clunk_fid:
999         p9_client_clunk(fid);
1000         fid = NULL;
1001
1002 error:
1003         if (fid && (fid != oldfid))
1004                 p9_fid_destroy(fid);
1005
1006         return ERR_PTR(err);
1007 }
1008 EXPORT_SYMBOL(p9_client_walk);
1009
1010 int p9_client_open(struct p9_fid *fid, int mode)
1011 {
1012         int err;
1013         struct p9_client *clnt;
1014         struct p9_req_t *req;
1015         struct p9_qid qid;
1016         int iounit;
1017
1018         P9_DPRINTK(P9_DEBUG_9P, ">>> TOPEN fid %d mode %d\n", fid->fid, mode);
1019         err = 0;
1020         clnt = fid->clnt;
1021
1022         if (fid->mode != -1)
1023                 return -EINVAL;
1024
1025         req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1026         if (IS_ERR(req)) {
1027                 err = PTR_ERR(req);
1028                 goto error;
1029         }
1030
1031         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1032         if (err) {
1033                 p9pdu_dump(1, req->rc);
1034                 goto free_and_error;
1035         }
1036
1037         P9_DPRINTK(P9_DEBUG_9P, "<<< ROPEN qid %x.%llx.%x iounit %x\n",
1038                                 qid.type,
1039                                 (unsigned long long)qid.path,
1040                                 qid.version, iounit);
1041
1042         fid->mode = mode;
1043         fid->iounit = iounit;
1044
1045 free_and_error:
1046         p9_free_req(clnt, req);
1047 error:
1048         return err;
1049 }
1050 EXPORT_SYMBOL(p9_client_open);
1051
1052 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1053                      char *extension)
1054 {
1055         int err;
1056         struct p9_client *clnt;
1057         struct p9_req_t *req;
1058         struct p9_qid qid;
1059         int iounit;
1060
1061         P9_DPRINTK(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1062                                                 fid->fid, name, perm, mode);
1063         err = 0;
1064         clnt = fid->clnt;
1065
1066         if (fid->mode != -1)
1067                 return -EINVAL;
1068
1069         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1070                                 mode, extension);
1071         if (IS_ERR(req)) {
1072                 err = PTR_ERR(req);
1073                 goto error;
1074         }
1075
1076         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1077         if (err) {
1078                 p9pdu_dump(1, req->rc);
1079                 goto free_and_error;
1080         }
1081
1082         P9_DPRINTK(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1083                                 qid.type,
1084                                 (unsigned long long)qid.path,
1085                                 qid.version, iounit);
1086
1087         fid->mode = mode;
1088         fid->iounit = iounit;
1089
1090 free_and_error:
1091         p9_free_req(clnt, req);
1092 error:
1093         return err;
1094 }
1095 EXPORT_SYMBOL(p9_client_fcreate);
1096
1097 int p9_client_clunk(struct p9_fid *fid)
1098 {
1099         int err;
1100         struct p9_client *clnt;
1101         struct p9_req_t *req;
1102
1103         P9_DPRINTK(P9_DEBUG_9P, ">>> TCLUNK fid %d\n", fid->fid);
1104         err = 0;
1105         clnt = fid->clnt;
1106
1107         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1108         if (IS_ERR(req)) {
1109                 err = PTR_ERR(req);
1110                 goto error;
1111         }
1112
1113         P9_DPRINTK(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1114
1115         p9_free_req(clnt, req);
1116         p9_fid_destroy(fid);
1117
1118 error:
1119         return err;
1120 }
1121 EXPORT_SYMBOL(p9_client_clunk);
1122
1123 int p9_client_remove(struct p9_fid *fid)
1124 {
1125         int err;
1126         struct p9_client *clnt;
1127         struct p9_req_t *req;
1128
1129         P9_DPRINTK(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1130         err = 0;
1131         clnt = fid->clnt;
1132
1133         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1134         if (IS_ERR(req)) {
1135                 err = PTR_ERR(req);
1136                 goto error;
1137         }
1138
1139         P9_DPRINTK(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1140
1141         p9_free_req(clnt, req);
1142         p9_fid_destroy(fid);
1143
1144 error:
1145         return err;
1146 }
1147 EXPORT_SYMBOL(p9_client_remove);
1148
1149 int
1150 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1151                                                                 u32 count)
1152 {
1153         int err, rsize, total;
1154         struct p9_client *clnt;
1155         struct p9_req_t *req;
1156         char *dataptr;
1157
1158         P9_DPRINTK(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n", fid->fid,
1159                                         (long long unsigned) offset, count);
1160         err = 0;
1161         clnt = fid->clnt;
1162         total = 0;
1163
1164         rsize = fid->iounit;
1165         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1166                 rsize = clnt->msize - P9_IOHDRSZ;
1167
1168         if (count < rsize)
1169                 rsize = count;
1170
1171         req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset, rsize);
1172         if (IS_ERR(req)) {
1173                 err = PTR_ERR(req);
1174                 goto error;
1175         }
1176
1177         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1178         if (err) {
1179                 p9pdu_dump(1, req->rc);
1180                 goto free_and_error;
1181         }
1182
1183         P9_DPRINTK(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1184
1185         if (data) {
1186                 memmove(data, dataptr, count);
1187         }
1188
1189         if (udata) {
1190                 err = copy_to_user(udata, dataptr, count);
1191                 if (err) {
1192                         err = -EFAULT;
1193                         goto free_and_error;
1194                 }
1195         }
1196
1197         p9_free_req(clnt, req);
1198         return count;
1199
1200 free_and_error:
1201         p9_free_req(clnt, req);
1202 error:
1203         return err;
1204 }
1205 EXPORT_SYMBOL(p9_client_read);
1206
1207 int
1208 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1209                                                         u64 offset, u32 count)
1210 {
1211         int err, rsize, total;
1212         struct p9_client *clnt;
1213         struct p9_req_t *req;
1214
1215         P9_DPRINTK(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1216                                 fid->fid, (long long unsigned) offset, count);
1217         err = 0;
1218         clnt = fid->clnt;
1219         total = 0;
1220
1221         rsize = fid->iounit;
1222         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1223                 rsize = clnt->msize - P9_IOHDRSZ;
1224
1225         if (count < rsize)
1226                 rsize = count;
1227         if (data)
1228                 req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid, offset,
1229                                                                 rsize, data);
1230         else
1231                 req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid, offset,
1232                                                                 rsize, udata);
1233         if (IS_ERR(req)) {
1234                 err = PTR_ERR(req);
1235                 goto error;
1236         }
1237
1238         err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1239         if (err) {
1240                 p9pdu_dump(1, req->rc);
1241                 goto free_and_error;
1242         }
1243
1244         P9_DPRINTK(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1245
1246         p9_free_req(clnt, req);
1247         return count;
1248
1249 free_and_error:
1250         p9_free_req(clnt, req);
1251 error:
1252         return err;
1253 }
1254 EXPORT_SYMBOL(p9_client_write);
1255
1256 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1257 {
1258         int err;
1259         struct p9_client *clnt;
1260         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1261         struct p9_req_t *req;
1262         u16 ignored;
1263
1264         P9_DPRINTK(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1265
1266         if (!ret)
1267                 return ERR_PTR(-ENOMEM);
1268
1269         err = 0;
1270         clnt = fid->clnt;
1271
1272         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1273         if (IS_ERR(req)) {
1274                 err = PTR_ERR(req);
1275                 goto error;
1276         }
1277
1278         err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1279         if (err) {
1280                 p9pdu_dump(1, req->rc);
1281                 p9_free_req(clnt, req);
1282                 goto error;
1283         }
1284
1285         P9_DPRINTK(P9_DEBUG_9P,
1286                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1287                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1288                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1289                 "<<<    uid=%d gid=%d n_muid=%d\n",
1290                 ret->size, ret->type, ret->dev, ret->qid.type,
1291                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1292                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1293                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1294                 ret->n_uid, ret->n_gid, ret->n_muid);
1295
1296         p9_free_req(clnt, req);
1297         return ret;
1298
1299 error:
1300         kfree(ret);
1301         return ERR_PTR(err);
1302 }
1303 EXPORT_SYMBOL(p9_client_stat);
1304
1305 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1306 {
1307         int ret;
1308
1309         /* NOTE: size shouldn't include its own length */
1310         /* size[2] type[2] dev[4] qid[13] */
1311         /* mode[4] atime[4] mtime[4] length[8]*/
1312         /* name[s] uid[s] gid[s] muid[s] */
1313         ret = 2+4+13+4+4+4+8+2+2+2+2;
1314
1315         if (wst->name)
1316                 ret += strlen(wst->name);
1317         if (wst->uid)
1318                 ret += strlen(wst->uid);
1319         if (wst->gid)
1320                 ret += strlen(wst->gid);
1321         if (wst->muid)
1322                 ret += strlen(wst->muid);
1323
1324         if ((proto_version == p9_proto_2000u) ||
1325                 (proto_version == p9_proto_2000L)) {
1326                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1327                 if (wst->extension)
1328                         ret += strlen(wst->extension);
1329         }
1330
1331         return ret;
1332 }
1333
1334 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1335 {
1336         int err;
1337         struct p9_req_t *req;
1338         struct p9_client *clnt;
1339
1340         err = 0;
1341         clnt = fid->clnt;
1342         wst->size = p9_client_statsize(wst, clnt->proto_version);
1343         P9_DPRINTK(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1344         P9_DPRINTK(P9_DEBUG_9P,
1345                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1346                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1347                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1348                 "     uid=%d gid=%d n_muid=%d\n",
1349                 wst->size, wst->type, wst->dev, wst->qid.type,
1350                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1351                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1352                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1353                 wst->n_uid, wst->n_gid, wst->n_muid);
1354
1355         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1356         if (IS_ERR(req)) {
1357                 err = PTR_ERR(req);
1358                 goto error;
1359         }
1360
1361         P9_DPRINTK(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1362
1363         p9_free_req(clnt, req);
1364 error:
1365         return err;
1366 }
1367 EXPORT_SYMBOL(p9_client_wstat);
1368
1369 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1370 {
1371         int err;
1372         struct p9_req_t *req;
1373         struct p9_client *clnt;
1374
1375         err = 0;
1376         clnt = fid->clnt;
1377
1378         P9_DPRINTK(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1379
1380         req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1381         if (IS_ERR(req)) {
1382                 err = PTR_ERR(req);
1383                 goto error;
1384         }
1385
1386         err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1387                 &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1388                 &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1389         if (err) {
1390                 p9pdu_dump(1, req->rc);
1391                 p9_free_req(clnt, req);
1392                 goto error;
1393         }
1394
1395         P9_DPRINTK(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1396                 "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1397                 "fsid %llu namelen %ld\n",
1398                 fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1399                 sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1400                 sb->fsid, (long int)sb->namelen);
1401
1402         p9_free_req(clnt, req);
1403 error:
1404         return err;
1405 }
1406 EXPORT_SYMBOL(p9_client_statfs);