client.c revision 45abdf1c7be80d6ec3b0b14e59ee75a0d5d9fb37
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
45enum {
46	Opt_msize,
47	Opt_trans,
48	Opt_legacy,
49	Opt_err,
50};
51
52static const match_table_t tokens = {
53	{Opt_msize, "msize=%u"},
54	{Opt_legacy, "noextend"},
55	{Opt_trans, "trans=%s"},
56	{Opt_err, NULL},
57};
58
59static struct p9_req_t *
60p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
61
62/**
63 * v9fs_parse_options - parse mount options into session structure
64 * @options: options string passed from mount
65 * @v9ses: existing v9fs session information
66 *
67 * Return 0 upon success, -ERRNO upon failure
68 */
69
70static int parse_opts(char *opts, struct p9_client *clnt)
71{
72	char *options;
73	char *p;
74	substring_t args[MAX_OPT_ARGS];
75	int option;
76	int ret = 0;
77
78	clnt->dotu = 1;
79	clnt->msize = 8192;
80
81	if (!opts)
82		return 0;
83
84	options = kstrdup(opts, GFP_KERNEL);
85	if (!options) {
86		P9_DPRINTK(P9_DEBUG_ERROR,
87				"failed to allocate copy of option string\n");
88		return -ENOMEM;
89	}
90
91	while ((p = strsep(&options, ",")) != NULL) {
92		int token;
93		if (!*p)
94			continue;
95		token = match_token(p, tokens, args);
96		if (token < Opt_trans) {
97			int r = match_int(&args[0], &option);
98			if (r < 0) {
99				P9_DPRINTK(P9_DEBUG_ERROR,
100					"integer field, but no integer?\n");
101				ret = r;
102				continue;
103			}
104		}
105		switch (token) {
106		case Opt_msize:
107			clnt->msize = option;
108			break;
109		case Opt_trans:
110			clnt->trans_mod = v9fs_get_trans_by_name(&args[0]);
111			break;
112		case Opt_legacy:
113			clnt->dotu = 0;
114			break;
115		default:
116			continue;
117		}
118	}
119
120	if (!clnt->trans_mod)
121		clnt->trans_mod = v9fs_get_default_trans();
122
123	kfree(options);
124	return ret;
125}
126
127/**
128 * p9_tag_alloc - lookup/allocate a request by tag
129 * @c: client session to lookup tag within
130 * @tag: numeric id for transaction
131 *
132 * this is a simple array lookup, but will grow the
133 * request_slots as necessary to accomodate transaction
134 * ids which did not previously have a slot.
135 *
136 * this code relies on the client spinlock to manage locks, its
137 * possible we should switch to something else, but I'd rather
138 * stick with something low-overhead for the common case.
139 *
140 */
141
142static struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag)
143{
144	unsigned long flags;
145	int row, col;
146	struct p9_req_t *req;
147
148	/* This looks up the original request by tag so we know which
149	 * buffer to read the data into */
150	tag++;
151
152	if (tag >= c->max_tag) {
153		spin_lock_irqsave(&c->lock, flags);
154		/* check again since original check was outside of lock */
155		while (tag >= c->max_tag) {
156			row = (tag / P9_ROW_MAXTAG);
157			c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
158					sizeof(struct p9_req_t), GFP_ATOMIC);
159
160			if (!c->reqs[row]) {
161				printk(KERN_ERR "Couldn't grow tag array\n");
162				spin_unlock_irqrestore(&c->lock, flags);
163				return ERR_PTR(-ENOMEM);
164			}
165			for (col = 0; col < P9_ROW_MAXTAG; col++) {
166				c->reqs[row][col].status = REQ_STATUS_IDLE;
167				c->reqs[row][col].tc = NULL;
168			}
169			c->max_tag += P9_ROW_MAXTAG;
170		}
171		spin_unlock_irqrestore(&c->lock, flags);
172	}
173	row = tag / P9_ROW_MAXTAG;
174	col = tag % P9_ROW_MAXTAG;
175
176	req = &c->reqs[row][col];
177	if (!req->tc) {
178		req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_KERNEL);
179		if (!req->wq) {
180			printk(KERN_ERR "Couldn't grow tag array\n");
181			return ERR_PTR(-ENOMEM);
182		}
183		init_waitqueue_head(req->wq);
184		req->tc = kmalloc(sizeof(struct p9_fcall)+c->msize,
185								GFP_KERNEL);
186		req->rc = kmalloc(sizeof(struct p9_fcall)+c->msize,
187								GFP_KERNEL);
188		if ((!req->tc) || (!req->rc)) {
189			printk(KERN_ERR "Couldn't grow tag array\n");
190			kfree(req->tc);
191			kfree(req->rc);
192			kfree(req->wq);
193			req->tc = req->rc = NULL;
194			req->wq = NULL;
195			return ERR_PTR(-ENOMEM);
196		}
197		req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
198		req->tc->capacity = c->msize;
199		req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall);
200		req->rc->capacity = c->msize;
201	}
202
203	p9pdu_reset(req->tc);
204	p9pdu_reset(req->rc);
205
206	req->flush_tag = 0;
207	req->tc->tag = tag-1;
208	req->status = REQ_STATUS_ALLOC;
209
210	return &c->reqs[row][col];
211}
212
213/**
214 * p9_tag_lookup - lookup a request by tag
215 * @c: client session to lookup tag within
216 * @tag: numeric id for transaction
217 *
218 */
219
220struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
221{
222	int row, col;
223
224	/* This looks up the original request by tag so we know which
225	 * buffer to read the data into */
226	tag++;
227
228	BUG_ON(tag >= c->max_tag);
229
230	row = tag / P9_ROW_MAXTAG;
231	col = tag % P9_ROW_MAXTAG;
232
233	return &c->reqs[row][col];
234}
235EXPORT_SYMBOL(p9_tag_lookup);
236
237/**
238 * p9_tag_init - setup tags structure and contents
239 * @tags: tags structure from the client struct
240 *
241 * This initializes the tags structure for each client instance.
242 *
243 */
244
245static int p9_tag_init(struct p9_client *c)
246{
247	int err = 0;
248
249	c->tagpool = p9_idpool_create();
250	if (IS_ERR(c->tagpool)) {
251		err = PTR_ERR(c->tagpool);
252		c->tagpool = NULL;
253		goto error;
254	}
255
256	p9_idpool_get(c->tagpool); /* reserve tag 0 */
257
258	c->max_tag = 0;
259error:
260	return err;
261}
262
263/**
264 * p9_tag_cleanup - cleans up tags structure and reclaims resources
265 * @tags: tags structure from the client struct
266 *
267 * This frees resources associated with the tags structure
268 *
269 */
270static void p9_tag_cleanup(struct p9_client *c)
271{
272	int row, col;
273
274	/* check to insure all requests are idle */
275	for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
276		for (col = 0; col < P9_ROW_MAXTAG; col++) {
277			if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
278				P9_DPRINTK(P9_DEBUG_MUX,
279				  "Attempting to cleanup non-free tag %d,%d\n",
280				  row, col);
281				/* TODO: delay execution of cleanup */
282				return;
283			}
284		}
285	}
286
287	if (c->tagpool)
288		p9_idpool_destroy(c->tagpool);
289
290	/* free requests associated with tags */
291	for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
292		for (col = 0; col < P9_ROW_MAXTAG; col++) {
293			kfree(c->reqs[row][col].wq);
294			kfree(c->reqs[row][col].tc);
295			kfree(c->reqs[row][col].rc);
296		}
297		kfree(c->reqs[row]);
298	}
299	c->max_tag = 0;
300}
301
302/**
303 * p9_free_req - free a request and clean-up as necessary
304 * c: client state
305 * r: request to release
306 *
307 */
308
309static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
310{
311	int tag = r->tc->tag;
312	P9_DPRINTK(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
313
314	r->status = REQ_STATUS_IDLE;
315	if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
316		p9_idpool_put(tag, c->tagpool);
317}
318
319/**
320 * p9_client_cb - call back from transport to client
321 * c: client state
322 * req: request received
323 *
324 */
325void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
326{
327	struct p9_req_t *other_req;
328	unsigned long flags;
329
330	P9_DPRINTK(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
331
332	if (req->status == REQ_STATUS_ERROR)
333		wake_up(req->wq);
334
335	if (req->flush_tag) { 			/* flush receive path */
336		P9_DPRINTK(P9_DEBUG_9P, "<<< RFLUSH %d\n", req->tc->tag);
337		spin_lock_irqsave(&c->lock, flags);
338		other_req = p9_tag_lookup(c, req->flush_tag);
339		if (other_req->status != REQ_STATUS_FLSH) /* stale flush */
340			spin_unlock_irqrestore(&c->lock, flags);
341		else {
342			other_req->status = REQ_STATUS_FLSHD;
343			spin_unlock_irqrestore(&c->lock, flags);
344			wake_up(other_req->wq);
345		}
346		p9_free_req(c, req);
347	} else { 				/* normal receive path */
348		P9_DPRINTK(P9_DEBUG_MUX, "normal: tag %d\n", req->tc->tag);
349		spin_lock_irqsave(&c->lock, flags);
350		if (req->status != REQ_STATUS_FLSHD)
351			req->status = REQ_STATUS_RCVD;
352		spin_unlock_irqrestore(&c->lock, flags);
353		wake_up(req->wq);
354		P9_DPRINTK(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
355	}
356}
357EXPORT_SYMBOL(p9_client_cb);
358
359/**
360 * p9_parse_header - parse header arguments out of a packet
361 * @pdu: packet to parse
362 * @size: size of packet
363 * @type: type of request
364 * @tag: tag of packet
365 * @rewind: set if we need to rewind offset afterwards
366 */
367
368int
369p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
370								int rewind)
371{
372	int8_t r_type;
373	int16_t r_tag;
374	int32_t r_size;
375	int offset = pdu->offset;
376	int err;
377
378	pdu->offset = 0;
379	if (pdu->size == 0)
380		pdu->size = 7;
381
382	err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
383	if (err)
384		goto rewind_and_exit;
385
386	pdu->size = r_size;
387	pdu->id = r_type;
388	pdu->tag = r_tag;
389
390	P9_DPRINTK(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n", pdu->size,
391							pdu->id, pdu->tag);
392
393	if (type)
394		*type = r_type;
395	if (tag)
396		*tag = r_tag;
397	if (size)
398		*size = r_size;
399
400
401rewind_and_exit:
402	if (rewind)
403		pdu->offset = offset;
404	return err;
405}
406EXPORT_SYMBOL(p9_parse_header);
407
408/**
409 * p9_check_errors - check 9p packet for error return and process it
410 * @c: current client instance
411 * @req: request to parse and check for error conditions
412 *
413 * returns error code if one is discovered, otherwise returns 0
414 *
415 * this will have to be more complicated if we have multiple
416 * error packet types
417 */
418
419static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
420{
421	int8_t type;
422	int err;
423
424	err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
425	if (err) {
426		P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
427		return err;
428	}
429
430	if (type == P9_RERROR) {
431		int ecode;
432		char *ename;
433
434		err = p9pdu_readf(req->rc, c->dotu, "s?d", &ename, &ecode);
435		if (err) {
436			P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n",
437									err);
438			return err;
439		}
440
441		if (c->dotu)
442			err = -ecode;
443
444		if (!err) {
445			err = p9_errstr2errno(ename, strlen(ename));
446
447			/* string match failed */
448			if (!err)
449				err = -ESERVERFAULT;
450		}
451
452		P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
453
454		kfree(ename);
455	} else
456		err = 0;
457
458	return err;
459}
460
461/**
462 * p9_client_flush - flush (cancel) a request
463 * c: client state
464 * req: request to cancel
465 *
466 * This sents a flush for a particular requests and links
467 * the flush request to the original request.  The current
468 * code only supports a single flush request although the protocol
469 * allows for multiple flush requests to be sent for a single request.
470 *
471 */
472
473static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
474{
475	struct p9_req_t *req;
476	int16_t oldtag;
477	int err;
478
479	err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
480	if (err)
481		return err;
482
483	P9_DPRINTK(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
484
485	req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
486	if (IS_ERR(req))
487		return PTR_ERR(req);
488
489	req->flush_tag = oldtag;
490
491	/* we don't free anything here because RPC isn't complete */
492	return 0;
493}
494
495/**
496 * p9_client_rpc - issue a request and wait for a response
497 * @c: client session
498 * @type: type of request
499 * @fmt: protocol format string (see protocol.c)
500 *
501 * Returns request structure (which client must free using p9_free_req)
502 */
503
504static struct p9_req_t *
505p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
506{
507	va_list ap;
508	int tag, err;
509	struct p9_req_t *req;
510	unsigned long flags;
511	int sigpending;
512	int flushed = 0;
513
514	P9_DPRINTK(P9_DEBUG_MUX, "client %p op %d\n", c, type);
515
516	if (c->status != Connected)
517		return ERR_PTR(-EIO);
518
519	if (signal_pending(current)) {
520		sigpending = 1;
521		clear_thread_flag(TIF_SIGPENDING);
522	} else
523		sigpending = 0;
524
525	tag = P9_NOTAG;
526	if (type != P9_TVERSION) {
527		tag = p9_idpool_get(c->tagpool);
528		if (tag < 0)
529			return ERR_PTR(-ENOMEM);
530	}
531
532	req = p9_tag_alloc(c, tag);
533	if (IS_ERR(req))
534		return req;
535
536	/* marshall the data */
537	p9pdu_prepare(req->tc, tag, type);
538	va_start(ap, fmt);
539	err = p9pdu_vwritef(req->tc, c->dotu, fmt, ap);
540	va_end(ap);
541	p9pdu_finalize(req->tc);
542
543	err = c->trans_mod->request(c, req);
544	if (err < 0) {
545		c->status = Disconnected;
546		goto reterr;
547	}
548
549	/* if it was a flush we just transmitted, return our tag */
550	if (type == P9_TFLUSH)
551		return req;
552again:
553	P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d\n", req->wq, tag);
554	err = wait_event_interruptible(*req->wq,
555						req->status >= REQ_STATUS_RCVD);
556	P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d returned %d (flushed=%d)\n",
557						req->wq, tag, err, flushed);
558
559	if (req->status == REQ_STATUS_ERROR) {
560		P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
561		err = req->t_err;
562	} else if (err == -ERESTARTSYS && flushed) {
563		P9_DPRINTK(P9_DEBUG_MUX, "flushed - going again\n");
564		goto again;
565	} else if (req->status == REQ_STATUS_FLSHD) {
566		P9_DPRINTK(P9_DEBUG_MUX, "flushed - erestartsys\n");
567		err = -ERESTARTSYS;
568	}
569
570	if ((err == -ERESTARTSYS) && (c->status == Connected) && (!flushed)) {
571		P9_DPRINTK(P9_DEBUG_MUX, "flushing\n");
572		spin_lock_irqsave(&c->lock, flags);
573		if (req->status == REQ_STATUS_SENT)
574			req->status = REQ_STATUS_FLSH;
575		spin_unlock_irqrestore(&c->lock, flags);
576		sigpending = 1;
577		flushed = 1;
578		clear_thread_flag(TIF_SIGPENDING);
579
580		if (c->trans_mod->cancel(c, req)) {
581			err = p9_client_flush(c, req);
582			if (err == 0)
583				goto again;
584		}
585	}
586
587	if (sigpending) {
588		spin_lock_irqsave(&current->sighand->siglock, flags);
589		recalc_sigpending();
590		spin_unlock_irqrestore(&current->sighand->siglock, flags);
591	}
592
593	if (err < 0)
594		goto reterr;
595
596	err = p9_check_errors(c, req);
597	if (!err) {
598		P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d\n", c, type);
599		return req;
600	}
601
602reterr:
603	P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d error: %d\n", c, type,
604									err);
605	p9_free_req(c, req);
606	return ERR_PTR(err);
607}
608
609static struct p9_fid *p9_fid_create(struct p9_client *clnt)
610{
611	int err;
612	struct p9_fid *fid;
613	unsigned long flags;
614
615	P9_DPRINTK(P9_DEBUG_FID, "clnt %p\n", clnt);
616	fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
617	if (!fid)
618		return ERR_PTR(-ENOMEM);
619
620	fid->fid = p9_idpool_get(clnt->fidpool);
621	if (fid->fid < 0) {
622		err = -ENOSPC;
623		goto error;
624	}
625
626	memset(&fid->qid, 0, sizeof(struct p9_qid));
627	fid->mode = -1;
628	fid->rdir_fpos = 0;
629	fid->uid = current->fsuid;
630	fid->clnt = clnt;
631	fid->aux = NULL;
632
633	spin_lock_irqsave(&clnt->lock, flags);
634	list_add(&fid->flist, &clnt->fidlist);
635	spin_unlock_irqrestore(&clnt->lock, flags);
636
637	return fid;
638
639error:
640	kfree(fid);
641	return ERR_PTR(err);
642}
643
644static void p9_fid_destroy(struct p9_fid *fid)
645{
646	struct p9_client *clnt;
647	unsigned long flags;
648
649	P9_DPRINTK(P9_DEBUG_FID, "fid %d\n", fid->fid);
650	clnt = fid->clnt;
651	p9_idpool_put(fid->fid, clnt->fidpool);
652	spin_lock_irqsave(&clnt->lock, flags);
653	list_del(&fid->flist);
654	spin_unlock_irqrestore(&clnt->lock, flags);
655	kfree(fid);
656}
657
658int p9_client_version(struct p9_client *c)
659{
660	int err = 0;
661	struct p9_req_t *req;
662	char *version;
663	int msize;
664
665	P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d extended %d\n",
666							c->msize, c->dotu);
667	req = p9_client_rpc(c, P9_TVERSION, "ds", c->msize,
668				c->dotu ? "9P2000.u" : "9P2000");
669	if (IS_ERR(req))
670		return PTR_ERR(req);
671
672	err = p9pdu_readf(req->rc, c->dotu, "ds", &msize, &version);
673	if (err) {
674		P9_DPRINTK(P9_DEBUG_9P, "version error %d\n", err);
675		p9pdu_dump(1, req->rc);
676		goto error;
677	}
678
679	P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
680	if (!memcmp(version, "9P2000.u", 8))
681		c->dotu = 1;
682	else if (!memcmp(version, "9P2000", 6))
683		c->dotu = 0;
684	else {
685		err = -EREMOTEIO;
686		goto error;
687	}
688
689	if (msize < c->msize)
690		c->msize = msize;
691
692error:
693	kfree(version);
694	p9_free_req(c, req);
695
696	return err;
697}
698EXPORT_SYMBOL(p9_client_version);
699
700struct p9_client *p9_client_create(const char *dev_name, char *options)
701{
702	int err;
703	struct p9_client *clnt;
704
705	err = 0;
706	clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
707	if (!clnt)
708		return ERR_PTR(-ENOMEM);
709
710	clnt->trans_mod = NULL;
711	clnt->trans = NULL;
712	spin_lock_init(&clnt->lock);
713	INIT_LIST_HEAD(&clnt->fidlist);
714	clnt->fidpool = p9_idpool_create();
715	if (IS_ERR(clnt->fidpool)) {
716		err = PTR_ERR(clnt->fidpool);
717		clnt->fidpool = NULL;
718		goto error;
719	}
720
721	p9_tag_init(clnt);
722
723	err = parse_opts(options, clnt);
724	if (err < 0)
725		goto error;
726
727	if (clnt->trans_mod == NULL) {
728		err = -EPROTONOSUPPORT;
729		P9_DPRINTK(P9_DEBUG_ERROR,
730				"No transport defined or default transport\n");
731		goto error;
732	}
733
734	P9_DPRINTK(P9_DEBUG_MUX, "clnt %p trans %p msize %d dotu %d\n",
735		clnt, clnt->trans_mod, clnt->msize, clnt->dotu);
736
737	err = clnt->trans_mod->create(clnt, dev_name, options);
738	if (err)
739		goto error;
740
741	if ((clnt->msize+P9_IOHDRSZ) > clnt->trans_mod->maxsize)
742		clnt->msize = clnt->trans_mod->maxsize-P9_IOHDRSZ;
743
744	err = p9_client_version(clnt);
745	if (err)
746		goto error;
747
748	return clnt;
749
750error:
751	p9_client_destroy(clnt);
752	return ERR_PTR(err);
753}
754EXPORT_SYMBOL(p9_client_create);
755
756void p9_client_destroy(struct p9_client *clnt)
757{
758	struct p9_fid *fid, *fidptr;
759
760	P9_DPRINTK(P9_DEBUG_MUX, "clnt %p\n", clnt);
761
762	if (clnt->trans_mod)
763		clnt->trans_mod->close(clnt);
764
765	v9fs_put_trans(clnt->trans_mod);
766
767	list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist)
768		p9_fid_destroy(fid);
769
770	if (clnt->fidpool)
771		p9_idpool_destroy(clnt->fidpool);
772
773	p9_tag_cleanup(clnt);
774
775	kfree(clnt);
776}
777EXPORT_SYMBOL(p9_client_destroy);
778
779void p9_client_disconnect(struct p9_client *clnt)
780{
781	P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
782	clnt->status = Disconnected;
783}
784EXPORT_SYMBOL(p9_client_disconnect);
785
786struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
787	char *uname, u32 n_uname, char *aname)
788{
789	int err;
790	struct p9_req_t *req;
791	struct p9_fid *fid;
792	struct p9_qid qid;
793
794	P9_DPRINTK(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
795					afid ? afid->fid : -1, uname, aname);
796	err = 0;
797
798	fid = p9_fid_create(clnt);
799	if (IS_ERR(fid)) {
800		err = PTR_ERR(fid);
801		fid = NULL;
802		goto error;
803	}
804
805	req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
806			afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
807	if (IS_ERR(req)) {
808		err = PTR_ERR(req);
809		goto error;
810	}
811
812	err = p9pdu_readf(req->rc, clnt->dotu, "Q", &qid);
813	if (err) {
814		p9pdu_dump(1, req->rc);
815		p9_free_req(clnt, req);
816		goto error;
817	}
818
819	P9_DPRINTK(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
820					qid.type, qid.path, qid.version);
821
822	memmove(&fid->qid, &qid, sizeof(struct p9_qid));
823
824	p9_free_req(clnt, req);
825	return fid;
826
827error:
828	if (fid)
829		p9_fid_destroy(fid);
830	return ERR_PTR(err);
831}
832EXPORT_SYMBOL(p9_client_attach);
833
834struct p9_fid *
835p9_client_auth(struct p9_client *clnt, char *uname, u32 n_uname, char *aname)
836{
837	int err;
838	struct p9_req_t *req;
839	struct p9_qid qid;
840	struct p9_fid *afid;
841
842	P9_DPRINTK(P9_DEBUG_9P, ">>> TAUTH uname %s aname %s\n", uname, aname);
843	err = 0;
844
845	afid = p9_fid_create(clnt);
846	if (IS_ERR(afid)) {
847		err = PTR_ERR(afid);
848		afid = NULL;
849		goto error;
850	}
851
852	req = p9_client_rpc(clnt, P9_TAUTH, "dss?d",
853			afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
854	if (IS_ERR(req)) {
855		err = PTR_ERR(req);
856		goto error;
857	}
858
859	err = p9pdu_readf(req->rc, clnt->dotu, "Q", &qid);
860	if (err) {
861		p9pdu_dump(1, req->rc);
862		p9_free_req(clnt, req);
863		goto error;
864	}
865
866	P9_DPRINTK(P9_DEBUG_9P, "<<< RAUTH qid %x.%llx.%x\n",
867					qid.type, qid.path, qid.version);
868
869	memmove(&afid->qid, &qid, sizeof(struct p9_qid));
870	p9_free_req(clnt, req);
871	return afid;
872
873error:
874	if (afid)
875		p9_fid_destroy(afid);
876	return ERR_PTR(err);
877}
878EXPORT_SYMBOL(p9_client_auth);
879
880struct p9_fid *p9_client_walk(struct p9_fid *oldfid, int nwname, char **wnames,
881	int clone)
882{
883	int err;
884	struct p9_client *clnt;
885	struct p9_fid *fid;
886	struct p9_qid *wqids;
887	struct p9_req_t *req;
888	int16_t nwqids, count;
889
890	err = 0;
891	clnt = oldfid->clnt;
892	if (clone) {
893		fid = p9_fid_create(clnt);
894		if (IS_ERR(fid)) {
895			err = PTR_ERR(fid);
896			fid = NULL;
897			goto error;
898		}
899
900		fid->uid = oldfid->uid;
901	} else
902		fid = oldfid;
903
904
905	P9_DPRINTK(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %d wname[0] %s\n",
906		oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
907
908	req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
909								nwname, wnames);
910	if (IS_ERR(req)) {
911		err = PTR_ERR(req);
912		goto error;
913	}
914
915	err = p9pdu_readf(req->rc, clnt->dotu, "R", &nwqids, &wqids);
916	if (err) {
917		p9pdu_dump(1, req->rc);
918		p9_free_req(clnt, req);
919		goto clunk_fid;
920	}
921	p9_free_req(clnt, req);
922
923	P9_DPRINTK(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
924
925	if (nwqids != nwname) {
926		err = -ENOENT;
927		goto clunk_fid;
928	}
929
930	for (count = 0; count < nwqids; count++)
931		P9_DPRINTK(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
932			count, wqids[count].type, wqids[count].path,
933			wqids[count].version);
934
935	if (nwname)
936		memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
937	else
938		fid->qid = oldfid->qid;
939
940	return fid;
941
942clunk_fid:
943	p9_client_clunk(fid);
944	fid = NULL;
945
946error:
947	if (fid && (fid != oldfid))
948		p9_fid_destroy(fid);
949
950	return ERR_PTR(err);
951}
952EXPORT_SYMBOL(p9_client_walk);
953
954int p9_client_open(struct p9_fid *fid, int mode)
955{
956	int err;
957	struct p9_client *clnt;
958	struct p9_req_t *req;
959	struct p9_qid qid;
960	int iounit;
961
962	P9_DPRINTK(P9_DEBUG_9P, ">>> TOPEN fid %d mode %d\n", fid->fid, mode);
963	err = 0;
964	clnt = fid->clnt;
965
966	if (fid->mode != -1)
967		return -EINVAL;
968
969	req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
970	if (IS_ERR(req)) {
971		err = PTR_ERR(req);
972		goto error;
973	}
974
975	err = p9pdu_readf(req->rc, clnt->dotu, "Qd", &qid, &iounit);
976	if (err) {
977		p9pdu_dump(1, req->rc);
978		goto free_and_error;
979	}
980
981	P9_DPRINTK(P9_DEBUG_9P, "<<< ROPEN qid %x.%llx.%x iounit %x\n",
982				qid.type, qid.path, qid.version, iounit);
983
984	fid->mode = mode;
985	fid->iounit = iounit;
986
987free_and_error:
988	p9_free_req(clnt, req);
989error:
990	return err;
991}
992EXPORT_SYMBOL(p9_client_open);
993
994int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
995		     char *extension)
996{
997	int err;
998	struct p9_client *clnt;
999	struct p9_req_t *req;
1000	struct p9_qid qid;
1001	int iounit;
1002
1003	P9_DPRINTK(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1004						fid->fid, name, perm, mode);
1005	err = 0;
1006	clnt = fid->clnt;
1007
1008	if (fid->mode != -1)
1009		return -EINVAL;
1010
1011	req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1012				mode, extension);
1013	if (IS_ERR(req)) {
1014		err = PTR_ERR(req);
1015		goto error;
1016	}
1017
1018	err = p9pdu_readf(req->rc, clnt->dotu, "Qd", &qid, &iounit);
1019	if (err) {
1020		p9pdu_dump(1, req->rc);
1021		goto free_and_error;
1022	}
1023
1024	P9_DPRINTK(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1025				qid.type, qid.path, qid.version, iounit);
1026
1027	fid->mode = mode;
1028	fid->iounit = iounit;
1029
1030free_and_error:
1031	p9_free_req(clnt, req);
1032error:
1033	return err;
1034}
1035EXPORT_SYMBOL(p9_client_fcreate);
1036
1037int p9_client_clunk(struct p9_fid *fid)
1038{
1039	int err;
1040	struct p9_client *clnt;
1041	struct p9_req_t *req;
1042
1043	P9_DPRINTK(P9_DEBUG_9P, ">>> TCLUNK fid %d\n", fid->fid);
1044	err = 0;
1045	clnt = fid->clnt;
1046
1047	req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1048	if (IS_ERR(req)) {
1049		err = PTR_ERR(req);
1050		goto error;
1051	}
1052
1053	P9_DPRINTK(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1054
1055	p9_free_req(clnt, req);
1056	p9_fid_destroy(fid);
1057
1058error:
1059	return err;
1060}
1061EXPORT_SYMBOL(p9_client_clunk);
1062
1063int p9_client_remove(struct p9_fid *fid)
1064{
1065	int err;
1066	struct p9_client *clnt;
1067	struct p9_req_t *req;
1068
1069	P9_DPRINTK(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1070	err = 0;
1071	clnt = fid->clnt;
1072
1073	req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1074	if (IS_ERR(req)) {
1075		err = PTR_ERR(req);
1076		goto error;
1077	}
1078
1079	P9_DPRINTK(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1080
1081	p9_free_req(clnt, req);
1082	p9_fid_destroy(fid);
1083
1084error:
1085	return err;
1086}
1087EXPORT_SYMBOL(p9_client_remove);
1088
1089int
1090p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1091								u32 count)
1092{
1093	int err, rsize, total;
1094	struct p9_client *clnt;
1095	struct p9_req_t *req;
1096	char *dataptr;
1097
1098	P9_DPRINTK(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n", fid->fid,
1099					(long long unsigned) offset, count);
1100	err = 0;
1101	clnt = fid->clnt;
1102	total = 0;
1103
1104	rsize = fid->iounit;
1105	if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1106		rsize = clnt->msize - P9_IOHDRSZ;
1107
1108	if (count < rsize)
1109		rsize = count;
1110
1111	req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset, rsize);
1112	if (IS_ERR(req)) {
1113		err = PTR_ERR(req);
1114		goto error;
1115	}
1116
1117	err = p9pdu_readf(req->rc, clnt->dotu, "D", &count, &dataptr);
1118	if (err) {
1119		p9pdu_dump(1, req->rc);
1120		goto free_and_error;
1121	}
1122
1123	P9_DPRINTK(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1124
1125	if (data) {
1126		memmove(data, dataptr, count);
1127		data += count;
1128	}
1129
1130	if (udata) {
1131		err = copy_to_user(udata, dataptr, count);
1132		if (err) {
1133			err = -EFAULT;
1134			goto free_and_error;
1135		}
1136	}
1137
1138	p9_free_req(clnt, req);
1139	return count;
1140
1141free_and_error:
1142	p9_free_req(clnt, req);
1143error:
1144	return err;
1145}
1146EXPORT_SYMBOL(p9_client_read);
1147
1148int
1149p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1150							u64 offset, u32 count)
1151{
1152	int err, rsize, total;
1153	struct p9_client *clnt;
1154	struct p9_req_t *req;
1155
1156	P9_DPRINTK(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1157				fid->fid, (long long unsigned) offset, count);
1158	err = 0;
1159	clnt = fid->clnt;
1160	total = 0;
1161
1162	rsize = fid->iounit;
1163	if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1164		rsize = clnt->msize - P9_IOHDRSZ;
1165
1166	if (count < rsize)
1167		rsize = count;
1168	if (data)
1169		req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid, offset,
1170								rsize, data);
1171	else
1172		req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid, offset,
1173								rsize, udata);
1174	if (IS_ERR(req)) {
1175		err = PTR_ERR(req);
1176		goto error;
1177	}
1178
1179	err = p9pdu_readf(req->rc, clnt->dotu, "d", &count);
1180	if (err) {
1181		p9pdu_dump(1, req->rc);
1182		goto free_and_error;
1183	}
1184
1185	P9_DPRINTK(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1186
1187	p9_free_req(clnt, req);
1188	return count;
1189
1190free_and_error:
1191	p9_free_req(clnt, req);
1192error:
1193	return err;
1194}
1195EXPORT_SYMBOL(p9_client_write);
1196
1197struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1198{
1199	int err;
1200	struct p9_client *clnt;
1201	struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1202	struct p9_req_t *req;
1203	u16 ignored;
1204
1205	P9_DPRINTK(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1206
1207	if (!ret)
1208		return ERR_PTR(-ENOMEM);
1209
1210	err = 0;
1211	clnt = fid->clnt;
1212
1213	req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1214	if (IS_ERR(req)) {
1215		err = PTR_ERR(req);
1216		goto error;
1217	}
1218
1219	err = p9pdu_readf(req->rc, clnt->dotu, "wS", &ignored, ret);
1220	if (err) {
1221		ret = ERR_PTR(err);
1222		p9pdu_dump(1, req->rc);
1223		goto free_and_error;
1224	}
1225
1226	P9_DPRINTK(P9_DEBUG_9P,
1227		"<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1228		"<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1229		"<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1230		"<<<    uid=%d gid=%d n_muid=%d\n",
1231		ret->size, ret->type, ret->dev, ret->qid.type,
1232		ret->qid.path, ret->qid.version, ret->mode,
1233		ret->atime, ret->mtime, ret->length, ret->name,
1234		ret->uid, ret->gid, ret->muid, ret->extension,
1235		ret->n_uid, ret->n_gid, ret->n_muid);
1236
1237free_and_error:
1238	p9_free_req(clnt, req);
1239error:
1240	return ret;
1241}
1242EXPORT_SYMBOL(p9_client_stat);
1243
1244int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1245{
1246	int err;
1247	struct p9_req_t *req;
1248	struct p9_client *clnt;
1249
1250	P9_DPRINTK(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1251	P9_DPRINTK(P9_DEBUG_9P,
1252		"     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1253		"     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1254		"     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1255		"     uid=%d gid=%d n_muid=%d\n",
1256		wst->size, wst->type, wst->dev, wst->qid.type,
1257		wst->qid.path, wst->qid.version, wst->mode,
1258		wst->atime, wst->mtime, wst->length, wst->name,
1259		wst->uid, wst->gid, wst->muid, wst->extension,
1260		wst->n_uid, wst->n_gid, wst->n_muid);
1261	err = 0;
1262	clnt = fid->clnt;
1263
1264	req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, 0, wst);
1265	if (IS_ERR(req)) {
1266		err = PTR_ERR(req);
1267		goto error;
1268	}
1269
1270	P9_DPRINTK(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1271
1272	p9_free_req(clnt, req);
1273error:
1274	return err;
1275}
1276EXPORT_SYMBOL(p9_client_wstat);
1277