9P2010.L handshake: Remove "dotu" variable
[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/sched.h>
33 #include <linux/uaccess.h>
34 #include <net/9p/9p.h>
35 #include <linux/parser.h>
36 #include <net/9p/client.h>
37 #include <net/9p/transport.h>
38 #include "protocol.h"
39
40 /*
41   * Client Option Parsing (code inspired by NFS code)
42   *  - a little lazy - parse all client options
43   */
44
45 enum {
46         Opt_msize,
47         Opt_trans,
48         Opt_legacy,
49         Opt_version,
50         Opt_err,
51 };
52
53 static const match_table_t tokens = {
54         {Opt_msize, "msize=%u"},
55         {Opt_legacy, "noextend"},
56         {Opt_trans, "trans=%s"},
57         {Opt_version, "version=%s"},
58         {Opt_err, NULL},
59 };
60
61 inline int p9_is_proto_dotl(struct p9_client *clnt)
62 {
63         return (clnt->proto_version == p9_proto_2010L);
64 }
65 EXPORT_SYMBOL(p9_is_proto_dotl);
66
67 inline int p9_is_proto_dotu(struct p9_client *clnt)
68 {
69         return (clnt->proto_version == p9_proto_2000u);
70 }
71 EXPORT_SYMBOL(p9_is_proto_dotu);
72
73 /* Interpret mount option for protocol version */
74 static unsigned char get_protocol_version(const substring_t *name)
75 {
76         unsigned char version = -EINVAL;
77         if (!strncmp("9p2000", name->from, name->to-name->from)) {
78                 version = p9_proto_legacy;
79                 P9_DPRINTK(P9_DEBUG_9P, "Protocol version: Legacy\n");
80         } else if (!strncmp("9p2000.u", name->from, name->to-name->from)) {
81                 version = p9_proto_2000u;
82                 P9_DPRINTK(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
83         } else if (!strncmp("9p2010.L", name->from, name->to-name->from)) {
84                 version = p9_proto_2010L;
85                 P9_DPRINTK(P9_DEBUG_9P, "Protocol version: 9P2010.L\n");
86         } else {
87                 P9_DPRINTK(P9_DEBUG_ERROR, "Unknown protocol version %s. ",
88                                                         name->from);
89         }
90         return version;
91 }
92
93 static struct p9_req_t *
94 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
95
96 /**
97  * parse_options - parse mount options into client structure
98  * @opts: options string passed from mount
99  * @clnt: existing v9fs client information
100  *
101  * Return 0 upon success, -ERRNO upon failure
102  */
103
104 static int parse_opts(char *opts, struct p9_client *clnt)
105 {
106         char *options, *tmp_options;
107         char *p;
108         substring_t args[MAX_OPT_ARGS];
109         int option;
110         int ret = 0;
111
112         clnt->proto_version = p9_proto_2000u;
113         clnt->msize = 8192;
114
115         if (!opts)
116                 return 0;
117
118         tmp_options = kstrdup(opts, GFP_KERNEL);
119         if (!tmp_options) {
120                 P9_DPRINTK(P9_DEBUG_ERROR,
121                                 "failed to allocate copy of option string\n");
122                 return -ENOMEM;
123         }
124         options = tmp_options;
125
126         while ((p = strsep(&options, ",")) != NULL) {
127                 int token;
128                 if (!*p)
129                         continue;
130                 token = match_token(p, tokens, args);
131                 if (token < Opt_trans) {
132                         int r = match_int(&args[0], &option);
133                         if (r < 0) {
134                                 P9_DPRINTK(P9_DEBUG_ERROR,
135                                         "integer field, but no integer?\n");
136                                 ret = r;
137                                 continue;
138                         }
139                 }
140                 switch (token) {
141                 case Opt_msize:
142                         clnt->msize = option;
143                         break;
144                 case Opt_trans:
145                         clnt->trans_mod = v9fs_get_trans_by_name(&args[0]);
146                         if(clnt->trans_mod == NULL) {
147                                 P9_DPRINTK(P9_DEBUG_ERROR,
148                                    "Could not find request transport: %s\n",
149                                    (char *) &args[0]);
150                                 ret = -EINVAL;
151                                 goto free_and_return;
152                         }
153                         break;
154                 case Opt_legacy:
155                         clnt->proto_version = p9_proto_legacy;
156                         break;
157                 case Opt_version:
158                         ret = get_protocol_version(&args[0]);
159                         if (ret == -EINVAL)
160                                 goto free_and_return;
161                         clnt->proto_version = ret;
162                         break;
163                 default:
164                         continue;
165                 }
166         }
167
168 free_and_return:
169         kfree(tmp_options);
170         return ret;
171 }
172
173 /**
174  * p9_tag_alloc - lookup/allocate a request by tag
175  * @c: client session to lookup tag within
176  * @tag: numeric id for transaction
177  *
178  * this is a simple array lookup, but will grow the
179  * request_slots as necessary to accomodate transaction
180  * ids which did not previously have a slot.
181  *
182  * this code relies on the client spinlock to manage locks, its
183  * possible we should switch to something else, but I'd rather
184  * stick with something low-overhead for the common case.
185  *
186  */
187
188 static struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag)
189 {
190         unsigned long flags;
191         int row, col;
192         struct p9_req_t *req;
193
194         /* This looks up the original request by tag so we know which
195          * buffer to read the data into */
196         tag++;
197
198         if (tag >= c->max_tag) {
199                 spin_lock_irqsave(&c->lock, flags);
200                 /* check again since original check was outside of lock */
201                 while (tag >= c->max_tag) {
202                         row = (tag / P9_ROW_MAXTAG);
203                         c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
204                                         sizeof(struct p9_req_t), GFP_ATOMIC);
205
206                         if (!c->reqs[row]) {
207                                 printk(KERN_ERR "Couldn't grow tag array\n");
208                                 spin_unlock_irqrestore(&c->lock, flags);
209                                 return ERR_PTR(-ENOMEM);
210                         }
211                         for (col = 0; col < P9_ROW_MAXTAG; col++) {
212                                 c->reqs[row][col].status = REQ_STATUS_IDLE;
213                                 c->reqs[row][col].tc = NULL;
214                         }
215                         c->max_tag += P9_ROW_MAXTAG;
216                 }
217                 spin_unlock_irqrestore(&c->lock, flags);
218         }
219         row = tag / P9_ROW_MAXTAG;
220         col = tag % P9_ROW_MAXTAG;
221
222         req = &c->reqs[row][col];
223         if (!req->tc) {
224                 req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_KERNEL);
225                 if (!req->wq) {
226                         printk(KERN_ERR "Couldn't grow tag array\n");
227                         return ERR_PTR(-ENOMEM);
228                 }
229                 init_waitqueue_head(req->wq);
230                 req->tc = kmalloc(sizeof(struct p9_fcall)+c->msize,
231                                                                 GFP_KERNEL);
232                 req->rc = kmalloc(sizeof(struct p9_fcall)+c->msize,
233                                                                 GFP_KERNEL);
234                 if ((!req->tc) || (!req->rc)) {
235                         printk(KERN_ERR "Couldn't grow tag array\n");
236                         kfree(req->tc);
237                         kfree(req->rc);
238                         kfree(req->wq);
239                         req->tc = req->rc = NULL;
240                         req->wq = NULL;
241                         return ERR_PTR(-ENOMEM);
242                 }
243                 req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
244                 req->tc->capacity = c->msize;
245                 req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall);
246                 req->rc->capacity = c->msize;
247         }
248
249         p9pdu_reset(req->tc);
250         p9pdu_reset(req->rc);
251
252         req->tc->tag = tag-1;
253         req->status = REQ_STATUS_ALLOC;
254
255         return &c->reqs[row][col];
256 }
257
258 /**
259  * p9_tag_lookup - lookup a request by tag
260  * @c: client session to lookup tag within
261  * @tag: numeric id for transaction
262  *
263  */
264
265 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
266 {
267         int row, col;
268
269         /* This looks up the original request by tag so we know which
270          * buffer to read the data into */
271         tag++;
272
273         BUG_ON(tag >= c->max_tag);
274
275         row = tag / P9_ROW_MAXTAG;
276         col = tag % P9_ROW_MAXTAG;
277
278         return &c->reqs[row][col];
279 }
280 EXPORT_SYMBOL(p9_tag_lookup);
281
282 /**
283  * p9_tag_init - setup tags structure and contents
284  * @c:  v9fs client struct
285  *
286  * This initializes the tags structure for each client instance.
287  *
288  */
289
290 static int p9_tag_init(struct p9_client *c)
291 {
292         int err = 0;
293
294         c->tagpool = p9_idpool_create();
295         if (IS_ERR(c->tagpool)) {
296                 err = PTR_ERR(c->tagpool);
297                 c->tagpool = NULL;
298                 goto error;
299         }
300
301         p9_idpool_get(c->tagpool); /* reserve tag 0 */
302
303         c->max_tag = 0;
304 error:
305         return err;
306 }
307
308 /**
309  * p9_tag_cleanup - cleans up tags structure and reclaims resources
310  * @c:  v9fs client struct
311  *
312  * This frees resources associated with the tags structure
313  *
314  */
315 static void p9_tag_cleanup(struct p9_client *c)
316 {
317         int row, col;
318
319         /* check to insure all requests are idle */
320         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
321                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
322                         if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
323                                 P9_DPRINTK(P9_DEBUG_MUX,
324                                   "Attempting to cleanup non-free tag %d,%d\n",
325                                   row, col);
326                                 /* TODO: delay execution of cleanup */
327                                 return;
328                         }
329                 }
330         }
331
332         if (c->tagpool)
333                 p9_idpool_destroy(c->tagpool);
334
335         /* free requests associated with tags */
336         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
337                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
338                         kfree(c->reqs[row][col].wq);
339                         kfree(c->reqs[row][col].tc);
340                         kfree(c->reqs[row][col].rc);
341                 }
342                 kfree(c->reqs[row]);
343         }
344         c->max_tag = 0;
345 }
346
347 /**
348  * p9_free_req - free a request and clean-up as necessary
349  * c: client state
350  * r: request to release
351  *
352  */
353
354 static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
355 {
356         int tag = r->tc->tag;
357         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
358
359         r->status = REQ_STATUS_IDLE;
360         if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
361                 p9_idpool_put(tag, c->tagpool);
362 }
363
364 /**
365  * p9_client_cb - call back from transport to client
366  * c: client state
367  * req: request received
368  *
369  */
370 void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
371 {
372         P9_DPRINTK(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
373         wake_up(req->wq);
374         P9_DPRINTK(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
375 }
376 EXPORT_SYMBOL(p9_client_cb);
377
378 /**
379  * p9_parse_header - parse header arguments out of a packet
380  * @pdu: packet to parse
381  * @size: size of packet
382  * @type: type of request
383  * @tag: tag of packet
384  * @rewind: set if we need to rewind offset afterwards
385  */
386
387 int
388 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
389                                                                 int rewind)
390 {
391         int8_t r_type;
392         int16_t r_tag;
393         int32_t r_size;
394         int offset = pdu->offset;
395         int err;
396
397         pdu->offset = 0;
398         if (pdu->size == 0)
399                 pdu->size = 7;
400
401         err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
402         if (err)
403                 goto rewind_and_exit;
404
405         pdu->size = r_size;
406         pdu->id = r_type;
407         pdu->tag = r_tag;
408
409         P9_DPRINTK(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n", pdu->size,
410                                                         pdu->id, pdu->tag);
411
412         if (type)
413                 *type = r_type;
414         if (tag)
415                 *tag = r_tag;
416         if (size)
417                 *size = r_size;
418
419
420 rewind_and_exit:
421         if (rewind)
422                 pdu->offset = offset;
423         return err;
424 }
425 EXPORT_SYMBOL(p9_parse_header);
426
427 /**
428  * p9_check_errors - check 9p packet for error return and process it
429  * @c: current client instance
430  * @req: request to parse and check for error conditions
431  *
432  * returns error code if one is discovered, otherwise returns 0
433  *
434  * this will have to be more complicated if we have multiple
435  * error packet types
436  */
437
438 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
439 {
440         int8_t type;
441         int err;
442
443         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
444         if (err) {
445                 P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
446                 return err;
447         }
448
449         if (type == P9_RERROR) {
450                 int ecode;
451                 char *ename;
452
453                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
454                                                         &ename, &ecode);
455                 if (err) {
456                         P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n",
457                                                                         err);
458                         return err;
459                 }
460
461                 if (p9_is_proto_dotu(c))
462                         err = -ecode;
463
464                 if (!err || !IS_ERR_VALUE(err))
465                         err = p9_errstr2errno(ename, strlen(ename));
466
467                 P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
468
469                 kfree(ename);
470         } else
471                 err = 0;
472
473         return err;
474 }
475
476 /**
477  * p9_client_flush - flush (cancel) a request
478  * @c: client state
479  * @oldreq: request to cancel
480  *
481  * This sents a flush for a particular requests and links
482  * the flush request to the original request.  The current
483  * code only supports a single flush request although the protocol
484  * allows for multiple flush requests to be sent for a single request.
485  *
486  */
487
488 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
489 {
490         struct p9_req_t *req;
491         int16_t oldtag;
492         int err;
493
494         err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
495         if (err)
496                 return err;
497
498         P9_DPRINTK(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
499
500         req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
501         if (IS_ERR(req))
502                 return PTR_ERR(req);
503
504
505         /* if we haven't received a response for oldreq,
506            remove it from the list. */
507         spin_lock(&c->lock);
508         if (oldreq->status == REQ_STATUS_FLSH)
509                 list_del(&oldreq->req_list);
510         spin_unlock(&c->lock);
511
512         p9_free_req(c, req);
513         return 0;
514 }
515
516 /**
517  * p9_client_rpc - issue a request and wait for a response
518  * @c: client session
519  * @type: type of request
520  * @fmt: protocol format string (see protocol.c)
521  *
522  * Returns request structure (which client must free using p9_free_req)
523  */
524
525 static struct p9_req_t *
526 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
527 {
528         va_list ap;
529         int tag, err;
530         struct p9_req_t *req;
531         unsigned long flags;
532         int sigpending;
533
534         P9_DPRINTK(P9_DEBUG_MUX, "client %p op %d\n", c, type);
535
536         if (c->status != Connected)
537                 return ERR_PTR(-EIO);
538
539         if (signal_pending(current)) {
540                 sigpending = 1;
541                 clear_thread_flag(TIF_SIGPENDING);
542         } else
543                 sigpending = 0;
544
545         tag = P9_NOTAG;
546         if (type != P9_TVERSION) {
547                 tag = p9_idpool_get(c->tagpool);
548                 if (tag < 0)
549                         return ERR_PTR(-ENOMEM);
550         }
551
552         req = p9_tag_alloc(c, tag);
553         if (IS_ERR(req))
554                 return req;
555
556         /* marshall the data */
557         p9pdu_prepare(req->tc, tag, type);
558         va_start(ap, fmt);
559         err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
560         va_end(ap);
561         p9pdu_finalize(req->tc);
562
563         err = c->trans_mod->request(c, req);
564         if (err < 0) {
565                 c->status = Disconnected;
566                 goto reterr;
567         }
568
569         P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d\n", req->wq, tag);
570         err = wait_event_interruptible(*req->wq,
571                                                 req->status >= REQ_STATUS_RCVD);
572         P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d returned %d\n",
573                                                 req->wq, tag, err);
574
575         if (req->status == REQ_STATUS_ERROR) {
576                 P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
577                 err = req->t_err;
578         }
579
580         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
581                 P9_DPRINTK(P9_DEBUG_MUX, "flushing\n");
582                 sigpending = 1;
583                 clear_thread_flag(TIF_SIGPENDING);
584
585                 if (c->trans_mod->cancel(c, req))
586                         p9_client_flush(c, req);
587
588                 /* if we received the response anyway, don't signal error */
589                 if (req->status == REQ_STATUS_RCVD)
590                         err = 0;
591         }
592
593         if (sigpending) {
594                 spin_lock_irqsave(&current->sighand->siglock, flags);
595                 recalc_sigpending();
596                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
597         }
598
599         if (err < 0)
600                 goto reterr;
601
602         err = p9_check_errors(c, req);
603         if (!err) {
604                 P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d\n", c, type);
605                 return req;
606         }
607
608 reterr:
609         P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d error: %d\n", c, type,
610                                                                         err);
611         p9_free_req(c, req);
612         return ERR_PTR(err);
613 }
614
615 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
616 {
617         int ret;
618         struct p9_fid *fid;
619         unsigned long flags;
620
621         P9_DPRINTK(P9_DEBUG_FID, "clnt %p\n", clnt);
622         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
623         if (!fid)
624                 return ERR_PTR(-ENOMEM);
625
626         ret = p9_idpool_get(clnt->fidpool);
627         if (ret < 0) {
628                 ret = -ENOSPC;
629                 goto error;
630         }
631         fid->fid = ret;
632
633         memset(&fid->qid, 0, sizeof(struct p9_qid));
634         fid->mode = -1;
635         fid->uid = current_fsuid();
636         fid->clnt = clnt;
637         fid->rdir = NULL;
638         spin_lock_irqsave(&clnt->lock, flags);
639         list_add(&fid->flist, &clnt->fidlist);
640         spin_unlock_irqrestore(&clnt->lock, flags);
641
642         return fid;
643
644 error:
645         kfree(fid);
646         return ERR_PTR(ret);
647 }
648
649 static void p9_fid_destroy(struct p9_fid *fid)
650 {
651         struct p9_client *clnt;
652         unsigned long flags;
653
654         P9_DPRINTK(P9_DEBUG_FID, "fid %d\n", fid->fid);
655         clnt = fid->clnt;
656         p9_idpool_put(fid->fid, clnt->fidpool);
657         spin_lock_irqsave(&clnt->lock, flags);
658         list_del(&fid->flist);
659         spin_unlock_irqrestore(&clnt->lock, flags);
660         kfree(fid->rdir);
661         kfree(fid);
662 }
663
664 int p9_client_version(struct p9_client *c)
665 {
666         int err = 0;
667         struct p9_req_t *req;
668         char *version;
669         int msize;
670
671         P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
672                                                 c->msize, c->proto_version);
673         req = p9_client_rpc(c, P9_TVERSION, "ds", c->msize,
674                                 p9_is_proto_dotu(c) ? "9P2000.u" : "9P2000");
675         if (IS_ERR(req))
676                 return PTR_ERR(req);
677
678         err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
679         if (err) {
680                 P9_DPRINTK(P9_DEBUG_9P, "version error %d\n", err);
681                 p9pdu_dump(1, req->rc);
682                 goto error;
683         }
684
685         P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
686         if (!strncmp(version, "9P2000.u", 8))
687                 c->proto_version = p9_proto_2000u;
688         else if (!strncmp(version, "9P2000", 6))
689                 c->proto_version = p9_proto_legacy;
690         else {
691                 err = -EREMOTEIO;
692                 goto error;
693         }
694
695         if (msize < c->msize)
696                 c->msize = msize;
697
698 error:
699         kfree(version);
700         p9_free_req(c, req);
701
702         return err;
703 }
704 EXPORT_SYMBOL(p9_client_version);
705
706 struct p9_client *p9_client_create(const char *dev_name, char *options)
707 {
708         int err;
709         struct p9_client *clnt;
710
711         err = 0;
712         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
713         if (!clnt)
714                 return ERR_PTR(-ENOMEM);
715
716         clnt->trans_mod = NULL;
717         clnt->trans = NULL;
718         spin_lock_init(&clnt->lock);
719         INIT_LIST_HEAD(&clnt->fidlist);
720
721         p9_tag_init(clnt);
722
723         err = parse_opts(options, clnt);
724         if (err < 0)
725                 goto free_client;
726
727         if (!clnt->trans_mod)
728                 clnt->trans_mod = v9fs_get_default_trans();
729
730         if (clnt->trans_mod == NULL) {
731                 err = -EPROTONOSUPPORT;
732                 P9_DPRINTK(P9_DEBUG_ERROR,
733                                 "No transport defined or default transport\n");
734                 goto free_client;
735         }
736
737         clnt->fidpool = p9_idpool_create();
738         if (IS_ERR(clnt->fidpool)) {
739                 err = PTR_ERR(clnt->fidpool);
740                 clnt->fidpool = NULL;
741                 goto put_trans;
742         }
743
744         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
745                 clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
746
747         err = clnt->trans_mod->create(clnt, dev_name, options);
748         if (err)
749                 goto destroy_fidpool;
750
751         if ((clnt->msize+P9_IOHDRSZ) > clnt->trans_mod->maxsize)
752                 clnt->msize = clnt->trans_mod->maxsize-P9_IOHDRSZ;
753
754         err = p9_client_version(clnt);
755         if (err)
756                 goto close_trans;
757
758         return clnt;
759
760 close_trans:
761         clnt->trans_mod->close(clnt);
762 destroy_fidpool:
763         p9_idpool_destroy(clnt->fidpool);
764 put_trans:
765         v9fs_put_trans(clnt->trans_mod);
766 free_client:
767         kfree(clnt);
768         return ERR_PTR(err);
769 }
770 EXPORT_SYMBOL(p9_client_create);
771
772 void p9_client_destroy(struct p9_client *clnt)
773 {
774         struct p9_fid *fid, *fidptr;
775
776         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p\n", clnt);
777
778         if (clnt->trans_mod)
779                 clnt->trans_mod->close(clnt);
780
781         v9fs_put_trans(clnt->trans_mod);
782
783         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist)
784                 p9_fid_destroy(fid);
785
786         if (clnt->fidpool)
787                 p9_idpool_destroy(clnt->fidpool);
788
789         p9_tag_cleanup(clnt);
790
791         kfree(clnt);
792 }
793 EXPORT_SYMBOL(p9_client_destroy);
794
795 void p9_client_disconnect(struct p9_client *clnt)
796 {
797         P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
798         clnt->status = Disconnected;
799 }
800 EXPORT_SYMBOL(p9_client_disconnect);
801
802 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
803         char *uname, u32 n_uname, char *aname)
804 {
805         int err;
806         struct p9_req_t *req;
807         struct p9_fid *fid;
808         struct p9_qid qid;
809
810         P9_DPRINTK(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
811                                         afid ? afid->fid : -1, uname, aname);
812         err = 0;
813
814         fid = p9_fid_create(clnt);
815         if (IS_ERR(fid)) {
816                 err = PTR_ERR(fid);
817                 fid = NULL;
818                 goto error;
819         }
820
821         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
822                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
823         if (IS_ERR(req)) {
824                 err = PTR_ERR(req);
825                 goto error;
826         }
827
828         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
829         if (err) {
830                 p9pdu_dump(1, req->rc);
831                 p9_free_req(clnt, req);
832                 goto error;
833         }
834
835         P9_DPRINTK(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
836                                         qid.type,
837                                         (unsigned long long)qid.path,
838                                         qid.version);
839
840         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
841
842         p9_free_req(clnt, req);
843         return fid;
844
845 error:
846         if (fid)
847                 p9_fid_destroy(fid);
848         return ERR_PTR(err);
849 }
850 EXPORT_SYMBOL(p9_client_attach);
851
852 struct p9_fid *
853 p9_client_auth(struct p9_client *clnt, char *uname, u32 n_uname, char *aname)
854 {
855         int err;
856         struct p9_req_t *req;
857         struct p9_qid qid;
858         struct p9_fid *afid;
859
860         P9_DPRINTK(P9_DEBUG_9P, ">>> TAUTH uname %s aname %s\n", uname, aname);
861         err = 0;
862
863         afid = p9_fid_create(clnt);
864         if (IS_ERR(afid)) {
865                 err = PTR_ERR(afid);
866                 afid = NULL;
867                 goto error;
868         }
869
870         req = p9_client_rpc(clnt, P9_TAUTH, "dss?d",
871                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
872         if (IS_ERR(req)) {
873                 err = PTR_ERR(req);
874                 goto error;
875         }
876
877         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
878         if (err) {
879                 p9pdu_dump(1, req->rc);
880                 p9_free_req(clnt, req);
881                 goto error;
882         }
883
884         P9_DPRINTK(P9_DEBUG_9P, "<<< RAUTH qid %x.%llx.%x\n",
885                                         qid.type,
886                                         (unsigned long long)qid.path,
887                                         qid.version);
888
889         memmove(&afid->qid, &qid, sizeof(struct p9_qid));
890         p9_free_req(clnt, req);
891         return afid;
892
893 error:
894         if (afid)
895                 p9_fid_destroy(afid);
896         return ERR_PTR(err);
897 }
898 EXPORT_SYMBOL(p9_client_auth);
899
900 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, int nwname, char **wnames,
901         int clone)
902 {
903         int err;
904         struct p9_client *clnt;
905         struct p9_fid *fid;
906         struct p9_qid *wqids;
907         struct p9_req_t *req;
908         int16_t nwqids, count;
909
910         err = 0;
911         clnt = oldfid->clnt;
912         if (clone) {
913                 fid = p9_fid_create(clnt);
914                 if (IS_ERR(fid)) {
915                         err = PTR_ERR(fid);
916                         fid = NULL;
917                         goto error;
918                 }
919
920                 fid->uid = oldfid->uid;
921         } else
922                 fid = oldfid;
923
924
925         P9_DPRINTK(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %d wname[0] %s\n",
926                 oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
927
928         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
929                                                                 nwname, wnames);
930         if (IS_ERR(req)) {
931                 err = PTR_ERR(req);
932                 goto error;
933         }
934
935         err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
936         if (err) {
937                 p9pdu_dump(1, req->rc);
938                 p9_free_req(clnt, req);
939                 goto clunk_fid;
940         }
941         p9_free_req(clnt, req);
942
943         P9_DPRINTK(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
944
945         if (nwqids != nwname) {
946                 err = -ENOENT;
947                 goto clunk_fid;
948         }
949
950         for (count = 0; count < nwqids; count++)
951                 P9_DPRINTK(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
952                         count, wqids[count].type,
953                         (unsigned long long)wqids[count].path,
954                         wqids[count].version);
955
956         if (nwname)
957                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
958         else
959                 fid->qid = oldfid->qid;
960
961         return fid;
962
963 clunk_fid:
964         p9_client_clunk(fid);
965         fid = NULL;
966
967 error:
968         if (fid && (fid != oldfid))
969                 p9_fid_destroy(fid);
970
971         return ERR_PTR(err);
972 }
973 EXPORT_SYMBOL(p9_client_walk);
974
975 int p9_client_open(struct p9_fid *fid, int mode)
976 {
977         int err;
978         struct p9_client *clnt;
979         struct p9_req_t *req;
980         struct p9_qid qid;
981         int iounit;
982
983         P9_DPRINTK(P9_DEBUG_9P, ">>> TOPEN fid %d mode %d\n", fid->fid, mode);
984         err = 0;
985         clnt = fid->clnt;
986
987         if (fid->mode != -1)
988                 return -EINVAL;
989
990         req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
991         if (IS_ERR(req)) {
992                 err = PTR_ERR(req);
993                 goto error;
994         }
995
996         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
997         if (err) {
998                 p9pdu_dump(1, req->rc);
999                 goto free_and_error;
1000         }
1001
1002         P9_DPRINTK(P9_DEBUG_9P, "<<< ROPEN qid %x.%llx.%x iounit %x\n",
1003                                 qid.type,
1004                                 (unsigned long long)qid.path,
1005                                 qid.version, iounit);
1006
1007         fid->mode = mode;
1008         fid->iounit = iounit;
1009
1010 free_and_error:
1011         p9_free_req(clnt, req);
1012 error:
1013         return err;
1014 }
1015 EXPORT_SYMBOL(p9_client_open);
1016
1017 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1018                      char *extension)
1019 {
1020         int err;
1021         struct p9_client *clnt;
1022         struct p9_req_t *req;
1023         struct p9_qid qid;
1024         int iounit;
1025
1026         P9_DPRINTK(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1027                                                 fid->fid, name, perm, mode);
1028         err = 0;
1029         clnt = fid->clnt;
1030
1031         if (fid->mode != -1)
1032                 return -EINVAL;
1033
1034         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1035                                 mode, extension);
1036         if (IS_ERR(req)) {
1037                 err = PTR_ERR(req);
1038                 goto error;
1039         }
1040
1041         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1042         if (err) {
1043                 p9pdu_dump(1, req->rc);
1044                 goto free_and_error;
1045         }
1046
1047         P9_DPRINTK(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1048                                 qid.type,
1049                                 (unsigned long long)qid.path,
1050                                 qid.version, iounit);
1051
1052         fid->mode = mode;
1053         fid->iounit = iounit;
1054
1055 free_and_error:
1056         p9_free_req(clnt, req);
1057 error:
1058         return err;
1059 }
1060 EXPORT_SYMBOL(p9_client_fcreate);
1061
1062 int p9_client_clunk(struct p9_fid *fid)
1063 {
1064         int err;
1065         struct p9_client *clnt;
1066         struct p9_req_t *req;
1067
1068         P9_DPRINTK(P9_DEBUG_9P, ">>> TCLUNK fid %d\n", fid->fid);
1069         err = 0;
1070         clnt = fid->clnt;
1071
1072         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1073         if (IS_ERR(req)) {
1074                 err = PTR_ERR(req);
1075                 goto error;
1076         }
1077
1078         P9_DPRINTK(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1079
1080         p9_free_req(clnt, req);
1081         p9_fid_destroy(fid);
1082
1083 error:
1084         return err;
1085 }
1086 EXPORT_SYMBOL(p9_client_clunk);
1087
1088 int p9_client_remove(struct p9_fid *fid)
1089 {
1090         int err;
1091         struct p9_client *clnt;
1092         struct p9_req_t *req;
1093
1094         P9_DPRINTK(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1095         err = 0;
1096         clnt = fid->clnt;
1097
1098         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1099         if (IS_ERR(req)) {
1100                 err = PTR_ERR(req);
1101                 goto error;
1102         }
1103
1104         P9_DPRINTK(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1105
1106         p9_free_req(clnt, req);
1107         p9_fid_destroy(fid);
1108
1109 error:
1110         return err;
1111 }
1112 EXPORT_SYMBOL(p9_client_remove);
1113
1114 int
1115 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1116                                                                 u32 count)
1117 {
1118         int err, rsize, total;
1119         struct p9_client *clnt;
1120         struct p9_req_t *req;
1121         char *dataptr;
1122
1123         P9_DPRINTK(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n", fid->fid,
1124                                         (long long unsigned) offset, count);
1125         err = 0;
1126         clnt = fid->clnt;
1127         total = 0;
1128
1129         rsize = fid->iounit;
1130         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1131                 rsize = clnt->msize - P9_IOHDRSZ;
1132
1133         if (count < rsize)
1134                 rsize = count;
1135
1136         req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset, rsize);
1137         if (IS_ERR(req)) {
1138                 err = PTR_ERR(req);
1139                 goto error;
1140         }
1141
1142         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1143         if (err) {
1144                 p9pdu_dump(1, req->rc);
1145                 goto free_and_error;
1146         }
1147
1148         P9_DPRINTK(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1149
1150         if (data) {
1151                 memmove(data, dataptr, count);
1152         }
1153
1154         if (udata) {
1155                 err = copy_to_user(udata, dataptr, count);
1156                 if (err) {
1157                         err = -EFAULT;
1158                         goto free_and_error;
1159                 }
1160         }
1161
1162         p9_free_req(clnt, req);
1163         return count;
1164
1165 free_and_error:
1166         p9_free_req(clnt, req);
1167 error:
1168         return err;
1169 }
1170 EXPORT_SYMBOL(p9_client_read);
1171
1172 int
1173 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1174                                                         u64 offset, u32 count)
1175 {
1176         int err, rsize, total;
1177         struct p9_client *clnt;
1178         struct p9_req_t *req;
1179
1180         P9_DPRINTK(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1181                                 fid->fid, (long long unsigned) offset, count);
1182         err = 0;
1183         clnt = fid->clnt;
1184         total = 0;
1185
1186         rsize = fid->iounit;
1187         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1188                 rsize = clnt->msize - P9_IOHDRSZ;
1189
1190         if (count < rsize)
1191                 rsize = count;
1192         if (data)
1193                 req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid, offset,
1194                                                                 rsize, data);
1195         else
1196                 req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid, offset,
1197                                                                 rsize, udata);
1198         if (IS_ERR(req)) {
1199                 err = PTR_ERR(req);
1200                 goto error;
1201         }
1202
1203         err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1204         if (err) {
1205                 p9pdu_dump(1, req->rc);
1206                 goto free_and_error;
1207         }
1208
1209         P9_DPRINTK(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1210
1211         p9_free_req(clnt, req);
1212         return count;
1213
1214 free_and_error:
1215         p9_free_req(clnt, req);
1216 error:
1217         return err;
1218 }
1219 EXPORT_SYMBOL(p9_client_write);
1220
1221 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1222 {
1223         int err;
1224         struct p9_client *clnt;
1225         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1226         struct p9_req_t *req;
1227         u16 ignored;
1228
1229         P9_DPRINTK(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1230
1231         if (!ret)
1232                 return ERR_PTR(-ENOMEM);
1233
1234         err = 0;
1235         clnt = fid->clnt;
1236
1237         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1238         if (IS_ERR(req)) {
1239                 err = PTR_ERR(req);
1240                 goto error;
1241         }
1242
1243         err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1244         if (err) {
1245                 p9pdu_dump(1, req->rc);
1246                 p9_free_req(clnt, req);
1247                 goto error;
1248         }
1249
1250         P9_DPRINTK(P9_DEBUG_9P,
1251                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1252                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1253                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1254                 "<<<    uid=%d gid=%d n_muid=%d\n",
1255                 ret->size, ret->type, ret->dev, ret->qid.type,
1256                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1257                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1258                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1259                 ret->n_uid, ret->n_gid, ret->n_muid);
1260
1261         p9_free_req(clnt, req);
1262         return ret;
1263
1264 error:
1265         kfree(ret);
1266         return ERR_PTR(err);
1267 }
1268 EXPORT_SYMBOL(p9_client_stat);
1269
1270 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1271 {
1272         int ret;
1273
1274         /* NOTE: size shouldn't include its own length */
1275         /* size[2] type[2] dev[4] qid[13] */
1276         /* mode[4] atime[4] mtime[4] length[8]*/
1277         /* name[s] uid[s] gid[s] muid[s] */
1278         ret = 2+4+13+4+4+4+8+2+2+2+2;
1279
1280         if (wst->name)
1281                 ret += strlen(wst->name);
1282         if (wst->uid)
1283                 ret += strlen(wst->uid);
1284         if (wst->gid)
1285                 ret += strlen(wst->gid);
1286         if (wst->muid)
1287                 ret += strlen(wst->muid);
1288
1289         if (proto_version == p9_proto_2000u) {
1290                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1291                 if (wst->extension)
1292                         ret += strlen(wst->extension);
1293         }
1294
1295         return ret;
1296 }
1297
1298 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1299 {
1300         int err;
1301         struct p9_req_t *req;
1302         struct p9_client *clnt;
1303
1304         err = 0;
1305         clnt = fid->clnt;
1306         wst->size = p9_client_statsize(wst, clnt->proto_version);
1307         P9_DPRINTK(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1308         P9_DPRINTK(P9_DEBUG_9P,
1309                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1310                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1311                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1312                 "     uid=%d gid=%d n_muid=%d\n",
1313                 wst->size, wst->type, wst->dev, wst->qid.type,
1314                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1315                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1316                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1317                 wst->n_uid, wst->n_gid, wst->n_muid);
1318
1319         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1320         if (IS_ERR(req)) {
1321                 err = PTR_ERR(req);
1322                 goto error;
1323         }
1324
1325         P9_DPRINTK(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1326
1327         p9_free_req(clnt, req);
1328 error:
1329         return err;
1330 }
1331 EXPORT_SYMBOL(p9_client_wstat);