xref: /linux/net/9p/client.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
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 			p9_is_proto_dotl(c))
465 			err = -ecode;
466 
467 		if (!err || !IS_ERR_VALUE(err))
468 			err = p9_errstr2errno(ename, strlen(ename));
469 
470 		P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
471 
472 		kfree(ename);
473 	} else
474 		err = 0;
475 
476 	return err;
477 }
478 
479 /**
480  * p9_client_flush - flush (cancel) a request
481  * @c: client state
482  * @oldreq: request to cancel
483  *
484  * This sents a flush for a particular requests and links
485  * the flush request to the original request.  The current
486  * code only supports a single flush request although the protocol
487  * allows for multiple flush requests to be sent for a single request.
488  *
489  */
490 
491 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
492 {
493 	struct p9_req_t *req;
494 	int16_t oldtag;
495 	int err;
496 
497 	err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
498 	if (err)
499 		return err;
500 
501 	P9_DPRINTK(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
502 
503 	req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
504 	if (IS_ERR(req))
505 		return PTR_ERR(req);
506 
507 
508 	/* if we haven't received a response for oldreq,
509 	   remove it from the list. */
510 	spin_lock(&c->lock);
511 	if (oldreq->status == REQ_STATUS_FLSH)
512 		list_del(&oldreq->req_list);
513 	spin_unlock(&c->lock);
514 
515 	p9_free_req(c, req);
516 	return 0;
517 }
518 
519 /**
520  * p9_client_rpc - issue a request and wait for a response
521  * @c: client session
522  * @type: type of request
523  * @fmt: protocol format string (see protocol.c)
524  *
525  * Returns request structure (which client must free using p9_free_req)
526  */
527 
528 static struct p9_req_t *
529 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
530 {
531 	va_list ap;
532 	int tag, err;
533 	struct p9_req_t *req;
534 	unsigned long flags;
535 	int sigpending;
536 
537 	P9_DPRINTK(P9_DEBUG_MUX, "client %p op %d\n", c, type);
538 
539 	/* we allow for any status other than disconnected */
540 	if (c->status == Disconnected)
541 		return ERR_PTR(-EIO);
542 
543 	/* if status is begin_disconnected we allow only clunk request */
544 	if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
545 		return ERR_PTR(-EIO);
546 
547 	if (signal_pending(current)) {
548 		sigpending = 1;
549 		clear_thread_flag(TIF_SIGPENDING);
550 	} else
551 		sigpending = 0;
552 
553 	tag = P9_NOTAG;
554 	if (type != P9_TVERSION) {
555 		tag = p9_idpool_get(c->tagpool);
556 		if (tag < 0)
557 			return ERR_PTR(-ENOMEM);
558 	}
559 
560 	req = p9_tag_alloc(c, tag);
561 	if (IS_ERR(req))
562 		return req;
563 
564 	/* marshall the data */
565 	p9pdu_prepare(req->tc, tag, type);
566 	va_start(ap, fmt);
567 	err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
568 	va_end(ap);
569 	p9pdu_finalize(req->tc);
570 
571 	err = c->trans_mod->request(c, req);
572 	if (err < 0) {
573 		c->status = Disconnected;
574 		goto reterr;
575 	}
576 
577 	P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d\n", req->wq, tag);
578 	err = wait_event_interruptible(*req->wq,
579 						req->status >= REQ_STATUS_RCVD);
580 	P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d returned %d\n",
581 						req->wq, tag, err);
582 
583 	if (req->status == REQ_STATUS_ERROR) {
584 		P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
585 		err = req->t_err;
586 	}
587 
588 	if ((err == -ERESTARTSYS) && (c->status == Connected)) {
589 		P9_DPRINTK(P9_DEBUG_MUX, "flushing\n");
590 		sigpending = 1;
591 		clear_thread_flag(TIF_SIGPENDING);
592 
593 		if (c->trans_mod->cancel(c, req))
594 			p9_client_flush(c, req);
595 
596 		/* if we received the response anyway, don't signal error */
597 		if (req->status == REQ_STATUS_RCVD)
598 			err = 0;
599 	}
600 
601 	if (sigpending) {
602 		spin_lock_irqsave(&current->sighand->siglock, flags);
603 		recalc_sigpending();
604 		spin_unlock_irqrestore(&current->sighand->siglock, flags);
605 	}
606 
607 	if (err < 0)
608 		goto reterr;
609 
610 	err = p9_check_errors(c, req);
611 	if (!err) {
612 		P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d\n", c, type);
613 		return req;
614 	}
615 
616 reterr:
617 	P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d error: %d\n", c, type,
618 									err);
619 	p9_free_req(c, req);
620 	return ERR_PTR(err);
621 }
622 
623 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
624 {
625 	int ret;
626 	struct p9_fid *fid;
627 	unsigned long flags;
628 
629 	P9_DPRINTK(P9_DEBUG_FID, "clnt %p\n", clnt);
630 	fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
631 	if (!fid)
632 		return ERR_PTR(-ENOMEM);
633 
634 	ret = p9_idpool_get(clnt->fidpool);
635 	if (ret < 0) {
636 		ret = -ENOSPC;
637 		goto error;
638 	}
639 	fid->fid = ret;
640 
641 	memset(&fid->qid, 0, sizeof(struct p9_qid));
642 	fid->mode = -1;
643 	fid->uid = current_fsuid();
644 	fid->clnt = clnt;
645 	fid->rdir = NULL;
646 	spin_lock_irqsave(&clnt->lock, flags);
647 	list_add(&fid->flist, &clnt->fidlist);
648 	spin_unlock_irqrestore(&clnt->lock, flags);
649 
650 	return fid;
651 
652 error:
653 	kfree(fid);
654 	return ERR_PTR(ret);
655 }
656 
657 static void p9_fid_destroy(struct p9_fid *fid)
658 {
659 	struct p9_client *clnt;
660 	unsigned long flags;
661 
662 	P9_DPRINTK(P9_DEBUG_FID, "fid %d\n", fid->fid);
663 	clnt = fid->clnt;
664 	p9_idpool_put(fid->fid, clnt->fidpool);
665 	spin_lock_irqsave(&clnt->lock, flags);
666 	list_del(&fid->flist);
667 	spin_unlock_irqrestore(&clnt->lock, flags);
668 	kfree(fid->rdir);
669 	kfree(fid);
670 }
671 
672 int p9_client_version(struct p9_client *c)
673 {
674 	int err = 0;
675 	struct p9_req_t *req;
676 	char *version;
677 	int msize;
678 
679 	P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
680 						c->msize, c->proto_version);
681 
682 	switch (c->proto_version) {
683 	case p9_proto_2000L:
684 		req = p9_client_rpc(c, P9_TVERSION, "ds",
685 					c->msize, "9P2000.L");
686 		break;
687 	case p9_proto_2000u:
688 		req = p9_client_rpc(c, P9_TVERSION, "ds",
689 					c->msize, "9P2000.u");
690 		break;
691 	case p9_proto_legacy:
692 		req = p9_client_rpc(c, P9_TVERSION, "ds",
693 					c->msize, "9P2000");
694 		break;
695 	default:
696 		return -EINVAL;
697 		break;
698 	}
699 
700 	if (IS_ERR(req))
701 		return PTR_ERR(req);
702 
703 	err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
704 	if (err) {
705 		P9_DPRINTK(P9_DEBUG_9P, "version error %d\n", err);
706 		p9pdu_dump(1, req->rc);
707 		goto error;
708 	}
709 
710 	P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
711 	if (!strncmp(version, "9P2000.L", 8))
712 		c->proto_version = p9_proto_2000L;
713 	else if (!strncmp(version, "9P2000.u", 8))
714 		c->proto_version = p9_proto_2000u;
715 	else if (!strncmp(version, "9P2000", 6))
716 		c->proto_version = p9_proto_legacy;
717 	else {
718 		err = -EREMOTEIO;
719 		goto error;
720 	}
721 
722 	if (msize < c->msize)
723 		c->msize = msize;
724 
725 error:
726 	kfree(version);
727 	p9_free_req(c, req);
728 
729 	return err;
730 }
731 EXPORT_SYMBOL(p9_client_version);
732 
733 struct p9_client *p9_client_create(const char *dev_name, char *options)
734 {
735 	int err;
736 	struct p9_client *clnt;
737 
738 	err = 0;
739 	clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
740 	if (!clnt)
741 		return ERR_PTR(-ENOMEM);
742 
743 	clnt->trans_mod = NULL;
744 	clnt->trans = NULL;
745 	spin_lock_init(&clnt->lock);
746 	INIT_LIST_HEAD(&clnt->fidlist);
747 
748 	p9_tag_init(clnt);
749 
750 	err = parse_opts(options, clnt);
751 	if (err < 0)
752 		goto free_client;
753 
754 	if (!clnt->trans_mod)
755 		clnt->trans_mod = v9fs_get_default_trans();
756 
757 	if (clnt->trans_mod == NULL) {
758 		err = -EPROTONOSUPPORT;
759 		P9_DPRINTK(P9_DEBUG_ERROR,
760 				"No transport defined or default transport\n");
761 		goto free_client;
762 	}
763 
764 	clnt->fidpool = p9_idpool_create();
765 	if (IS_ERR(clnt->fidpool)) {
766 		err = PTR_ERR(clnt->fidpool);
767 		clnt->fidpool = NULL;
768 		goto put_trans;
769 	}
770 
771 	P9_DPRINTK(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
772 		clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
773 
774 	err = clnt->trans_mod->create(clnt, dev_name, options);
775 	if (err)
776 		goto destroy_fidpool;
777 
778 	if ((clnt->msize+P9_IOHDRSZ) > clnt->trans_mod->maxsize)
779 		clnt->msize = clnt->trans_mod->maxsize-P9_IOHDRSZ;
780 
781 	err = p9_client_version(clnt);
782 	if (err)
783 		goto close_trans;
784 
785 	return clnt;
786 
787 close_trans:
788 	clnt->trans_mod->close(clnt);
789 destroy_fidpool:
790 	p9_idpool_destroy(clnt->fidpool);
791 put_trans:
792 	v9fs_put_trans(clnt->trans_mod);
793 free_client:
794 	kfree(clnt);
795 	return ERR_PTR(err);
796 }
797 EXPORT_SYMBOL(p9_client_create);
798 
799 void p9_client_destroy(struct p9_client *clnt)
800 {
801 	struct p9_fid *fid, *fidptr;
802 
803 	P9_DPRINTK(P9_DEBUG_MUX, "clnt %p\n", clnt);
804 
805 	if (clnt->trans_mod)
806 		clnt->trans_mod->close(clnt);
807 
808 	v9fs_put_trans(clnt->trans_mod);
809 
810 	list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
811 		printk(KERN_INFO "Found fid %d not clunked\n", fid->fid);
812 		p9_fid_destroy(fid);
813 	}
814 
815 	if (clnt->fidpool)
816 		p9_idpool_destroy(clnt->fidpool);
817 
818 	p9_tag_cleanup(clnt);
819 
820 	kfree(clnt);
821 }
822 EXPORT_SYMBOL(p9_client_destroy);
823 
824 void p9_client_disconnect(struct p9_client *clnt)
825 {
826 	P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
827 	clnt->status = Disconnected;
828 }
829 EXPORT_SYMBOL(p9_client_disconnect);
830 
831 void p9_client_begin_disconnect(struct p9_client *clnt)
832 {
833 	P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
834 	clnt->status = BeginDisconnect;
835 }
836 EXPORT_SYMBOL(p9_client_begin_disconnect);
837 
838 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
839 	char *uname, u32 n_uname, char *aname)
840 {
841 	int err;
842 	struct p9_req_t *req;
843 	struct p9_fid *fid;
844 	struct p9_qid qid;
845 
846 	P9_DPRINTK(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
847 					afid ? afid->fid : -1, uname, aname);
848 	err = 0;
849 
850 	fid = p9_fid_create(clnt);
851 	if (IS_ERR(fid)) {
852 		err = PTR_ERR(fid);
853 		fid = NULL;
854 		goto error;
855 	}
856 
857 	req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
858 			afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
859 	if (IS_ERR(req)) {
860 		err = PTR_ERR(req);
861 		goto error;
862 	}
863 
864 	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
865 	if (err) {
866 		p9pdu_dump(1, req->rc);
867 		p9_free_req(clnt, req);
868 		goto error;
869 	}
870 
871 	P9_DPRINTK(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
872 					qid.type,
873 					(unsigned long long)qid.path,
874 					qid.version);
875 
876 	memmove(&fid->qid, &qid, sizeof(struct p9_qid));
877 
878 	p9_free_req(clnt, req);
879 	return fid;
880 
881 error:
882 	if (fid)
883 		p9_fid_destroy(fid);
884 	return ERR_PTR(err);
885 }
886 EXPORT_SYMBOL(p9_client_attach);
887 
888 struct p9_fid *
889 p9_client_auth(struct p9_client *clnt, char *uname, u32 n_uname, char *aname)
890 {
891 	int err;
892 	struct p9_req_t *req;
893 	struct p9_qid qid;
894 	struct p9_fid *afid;
895 
896 	P9_DPRINTK(P9_DEBUG_9P, ">>> TAUTH uname %s aname %s\n", uname, aname);
897 	err = 0;
898 
899 	afid = p9_fid_create(clnt);
900 	if (IS_ERR(afid)) {
901 		err = PTR_ERR(afid);
902 		afid = NULL;
903 		goto error;
904 	}
905 
906 	req = p9_client_rpc(clnt, P9_TAUTH, "dss?d",
907 			afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
908 	if (IS_ERR(req)) {
909 		err = PTR_ERR(req);
910 		goto error;
911 	}
912 
913 	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
914 	if (err) {
915 		p9pdu_dump(1, req->rc);
916 		p9_free_req(clnt, req);
917 		goto error;
918 	}
919 
920 	P9_DPRINTK(P9_DEBUG_9P, "<<< RAUTH qid %x.%llx.%x\n",
921 					qid.type,
922 					(unsigned long long)qid.path,
923 					qid.version);
924 
925 	memmove(&afid->qid, &qid, sizeof(struct p9_qid));
926 	p9_free_req(clnt, req);
927 	return afid;
928 
929 error:
930 	if (afid)
931 		p9_fid_destroy(afid);
932 	return ERR_PTR(err);
933 }
934 EXPORT_SYMBOL(p9_client_auth);
935 
936 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, int nwname, char **wnames,
937 	int clone)
938 {
939 	int err;
940 	struct p9_client *clnt;
941 	struct p9_fid *fid;
942 	struct p9_qid *wqids;
943 	struct p9_req_t *req;
944 	int16_t nwqids, count;
945 
946 	err = 0;
947 	clnt = oldfid->clnt;
948 	if (clone) {
949 		fid = p9_fid_create(clnt);
950 		if (IS_ERR(fid)) {
951 			err = PTR_ERR(fid);
952 			fid = NULL;
953 			goto error;
954 		}
955 
956 		fid->uid = oldfid->uid;
957 	} else
958 		fid = oldfid;
959 
960 
961 	P9_DPRINTK(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %d wname[0] %s\n",
962 		oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
963 
964 	req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
965 								nwname, wnames);
966 	if (IS_ERR(req)) {
967 		err = PTR_ERR(req);
968 		goto error;
969 	}
970 
971 	err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
972 	if (err) {
973 		p9pdu_dump(1, req->rc);
974 		p9_free_req(clnt, req);
975 		goto clunk_fid;
976 	}
977 	p9_free_req(clnt, req);
978 
979 	P9_DPRINTK(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
980 
981 	if (nwqids != nwname) {
982 		err = -ENOENT;
983 		goto clunk_fid;
984 	}
985 
986 	for (count = 0; count < nwqids; count++)
987 		P9_DPRINTK(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
988 			count, wqids[count].type,
989 			(unsigned long long)wqids[count].path,
990 			wqids[count].version);
991 
992 	if (nwname)
993 		memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
994 	else
995 		fid->qid = oldfid->qid;
996 
997 	return fid;
998 
999 clunk_fid:
1000 	p9_client_clunk(fid);
1001 	fid = NULL;
1002 
1003 error:
1004 	if (fid && (fid != oldfid))
1005 		p9_fid_destroy(fid);
1006 
1007 	return ERR_PTR(err);
1008 }
1009 EXPORT_SYMBOL(p9_client_walk);
1010 
1011 int p9_client_open(struct p9_fid *fid, int mode)
1012 {
1013 	int err;
1014 	struct p9_client *clnt;
1015 	struct p9_req_t *req;
1016 	struct p9_qid qid;
1017 	int iounit;
1018 
1019 	clnt = fid->clnt;
1020 	P9_DPRINTK(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1021 		p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1022 	err = 0;
1023 
1024 	if (fid->mode != -1)
1025 		return -EINVAL;
1026 
1027 	if (p9_is_proto_dotl(clnt))
1028 		req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1029 	else
1030 		req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1031 	if (IS_ERR(req)) {
1032 		err = PTR_ERR(req);
1033 		goto error;
1034 	}
1035 
1036 	err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1037 	if (err) {
1038 		p9pdu_dump(1, req->rc);
1039 		goto free_and_error;
1040 	}
1041 
1042 	P9_DPRINTK(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1043 		p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1044 		(unsigned long long)qid.path, qid.version, iounit);
1045 
1046 	fid->mode = mode;
1047 	fid->iounit = iounit;
1048 
1049 free_and_error:
1050 	p9_free_req(clnt, req);
1051 error:
1052 	return err;
1053 }
1054 EXPORT_SYMBOL(p9_client_open);
1055 
1056 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
1057 		gid_t gid, struct p9_qid *qid)
1058 {
1059 	int err = 0;
1060 	struct p9_client *clnt;
1061 	struct p9_req_t *req;
1062 	int iounit;
1063 
1064 	P9_DPRINTK(P9_DEBUG_9P,
1065 			">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1066 			ofid->fid, name, flags, mode, gid);
1067 	clnt = ofid->clnt;
1068 
1069 	if (ofid->mode != -1)
1070 		return -EINVAL;
1071 
1072 	req = p9_client_rpc(clnt, P9_TLCREATE, "dsddd", ofid->fid, name, flags,
1073 			mode, gid);
1074 	if (IS_ERR(req)) {
1075 		err = PTR_ERR(req);
1076 		goto error;
1077 	}
1078 
1079 	err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1080 	if (err) {
1081 		p9pdu_dump(1, req->rc);
1082 		goto free_and_error;
1083 	}
1084 
1085 	P9_DPRINTK(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1086 			qid->type,
1087 			(unsigned long long)qid->path,
1088 			qid->version, iounit);
1089 
1090 	ofid->mode = mode;
1091 	ofid->iounit = iounit;
1092 
1093 free_and_error:
1094 	p9_free_req(clnt, req);
1095 error:
1096 	return err;
1097 }
1098 EXPORT_SYMBOL(p9_client_create_dotl);
1099 
1100 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1101 		     char *extension)
1102 {
1103 	int err;
1104 	struct p9_client *clnt;
1105 	struct p9_req_t *req;
1106 	struct p9_qid qid;
1107 	int iounit;
1108 
1109 	P9_DPRINTK(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1110 						fid->fid, name, perm, mode);
1111 	err = 0;
1112 	clnt = fid->clnt;
1113 
1114 	if (fid->mode != -1)
1115 		return -EINVAL;
1116 
1117 	req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1118 				mode, extension);
1119 	if (IS_ERR(req)) {
1120 		err = PTR_ERR(req);
1121 		goto error;
1122 	}
1123 
1124 	err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1125 	if (err) {
1126 		p9pdu_dump(1, req->rc);
1127 		goto free_and_error;
1128 	}
1129 
1130 	P9_DPRINTK(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1131 				qid.type,
1132 				(unsigned long long)qid.path,
1133 				qid.version, iounit);
1134 
1135 	fid->mode = mode;
1136 	fid->iounit = iounit;
1137 
1138 free_and_error:
1139 	p9_free_req(clnt, req);
1140 error:
1141 	return err;
1142 }
1143 EXPORT_SYMBOL(p9_client_fcreate);
1144 
1145 int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, gid_t gid,
1146 		struct p9_qid *qid)
1147 {
1148 	int err = 0;
1149 	struct p9_client *clnt;
1150 	struct p9_req_t *req;
1151 
1152 	P9_DPRINTK(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1153 			dfid->fid, name, symtgt);
1154 	clnt = dfid->clnt;
1155 
1156 	req = p9_client_rpc(clnt, P9_TSYMLINK, "dssd", dfid->fid, name, symtgt,
1157 			gid);
1158 	if (IS_ERR(req)) {
1159 		err = PTR_ERR(req);
1160 		goto error;
1161 	}
1162 
1163 	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1164 	if (err) {
1165 		p9pdu_dump(1, req->rc);
1166 		goto free_and_error;
1167 	}
1168 
1169 	P9_DPRINTK(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1170 			qid->type, (unsigned long long)qid->path, qid->version);
1171 
1172 free_and_error:
1173 	p9_free_req(clnt, req);
1174 error:
1175 	return err;
1176 }
1177 EXPORT_SYMBOL(p9_client_symlink);
1178 
1179 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
1180 {
1181 	struct p9_client *clnt;
1182 	struct p9_req_t *req;
1183 
1184 	P9_DPRINTK(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1185 			dfid->fid, oldfid->fid, newname);
1186 	clnt = dfid->clnt;
1187 	req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1188 			newname);
1189 	if (IS_ERR(req))
1190 		return PTR_ERR(req);
1191 
1192 	P9_DPRINTK(P9_DEBUG_9P, "<<< RLINK\n");
1193 	p9_free_req(clnt, req);
1194 	return 0;
1195 }
1196 EXPORT_SYMBOL(p9_client_link);
1197 
1198 int p9_client_clunk(struct p9_fid *fid)
1199 {
1200 	int err;
1201 	struct p9_client *clnt;
1202 	struct p9_req_t *req;
1203 
1204 	P9_DPRINTK(P9_DEBUG_9P, ">>> TCLUNK fid %d\n", fid->fid);
1205 	err = 0;
1206 	clnt = fid->clnt;
1207 
1208 	req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1209 	if (IS_ERR(req)) {
1210 		err = PTR_ERR(req);
1211 		goto error;
1212 	}
1213 
1214 	P9_DPRINTK(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1215 
1216 	p9_free_req(clnt, req);
1217 	p9_fid_destroy(fid);
1218 
1219 error:
1220 	return err;
1221 }
1222 EXPORT_SYMBOL(p9_client_clunk);
1223 
1224 int p9_client_remove(struct p9_fid *fid)
1225 {
1226 	int err;
1227 	struct p9_client *clnt;
1228 	struct p9_req_t *req;
1229 
1230 	P9_DPRINTK(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1231 	err = 0;
1232 	clnt = fid->clnt;
1233 
1234 	req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1235 	if (IS_ERR(req)) {
1236 		err = PTR_ERR(req);
1237 		goto error;
1238 	}
1239 
1240 	P9_DPRINTK(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1241 
1242 	p9_free_req(clnt, req);
1243 error:
1244 	p9_fid_destroy(fid);
1245 	return err;
1246 }
1247 EXPORT_SYMBOL(p9_client_remove);
1248 
1249 int
1250 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1251 								u32 count)
1252 {
1253 	int err, rsize, total;
1254 	struct p9_client *clnt;
1255 	struct p9_req_t *req;
1256 	char *dataptr;
1257 
1258 	P9_DPRINTK(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n", fid->fid,
1259 					(long long unsigned) offset, count);
1260 	err = 0;
1261 	clnt = fid->clnt;
1262 	total = 0;
1263 
1264 	rsize = fid->iounit;
1265 	if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1266 		rsize = clnt->msize - P9_IOHDRSZ;
1267 
1268 	if (count < rsize)
1269 		rsize = count;
1270 
1271 	req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset, rsize);
1272 	if (IS_ERR(req)) {
1273 		err = PTR_ERR(req);
1274 		goto error;
1275 	}
1276 
1277 	err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1278 	if (err) {
1279 		p9pdu_dump(1, req->rc);
1280 		goto free_and_error;
1281 	}
1282 
1283 	P9_DPRINTK(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1284 
1285 	if (data) {
1286 		memmove(data, dataptr, count);
1287 	}
1288 
1289 	if (udata) {
1290 		err = copy_to_user(udata, dataptr, count);
1291 		if (err) {
1292 			err = -EFAULT;
1293 			goto free_and_error;
1294 		}
1295 	}
1296 
1297 	p9_free_req(clnt, req);
1298 	return count;
1299 
1300 free_and_error:
1301 	p9_free_req(clnt, req);
1302 error:
1303 	return err;
1304 }
1305 EXPORT_SYMBOL(p9_client_read);
1306 
1307 int
1308 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1309 							u64 offset, u32 count)
1310 {
1311 	int err, rsize, total;
1312 	struct p9_client *clnt;
1313 	struct p9_req_t *req;
1314 
1315 	P9_DPRINTK(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1316 				fid->fid, (long long unsigned) offset, count);
1317 	err = 0;
1318 	clnt = fid->clnt;
1319 	total = 0;
1320 
1321 	rsize = fid->iounit;
1322 	if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1323 		rsize = clnt->msize - P9_IOHDRSZ;
1324 
1325 	if (count < rsize)
1326 		rsize = count;
1327 	if (data)
1328 		req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid, offset,
1329 								rsize, data);
1330 	else
1331 		req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid, offset,
1332 								rsize, udata);
1333 	if (IS_ERR(req)) {
1334 		err = PTR_ERR(req);
1335 		goto error;
1336 	}
1337 
1338 	err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1339 	if (err) {
1340 		p9pdu_dump(1, req->rc);
1341 		goto free_and_error;
1342 	}
1343 
1344 	P9_DPRINTK(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1345 
1346 	p9_free_req(clnt, req);
1347 	return count;
1348 
1349 free_and_error:
1350 	p9_free_req(clnt, req);
1351 error:
1352 	return err;
1353 }
1354 EXPORT_SYMBOL(p9_client_write);
1355 
1356 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1357 {
1358 	int err;
1359 	struct p9_client *clnt;
1360 	struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1361 	struct p9_req_t *req;
1362 	u16 ignored;
1363 
1364 	P9_DPRINTK(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1365 
1366 	if (!ret)
1367 		return ERR_PTR(-ENOMEM);
1368 
1369 	err = 0;
1370 	clnt = fid->clnt;
1371 
1372 	req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1373 	if (IS_ERR(req)) {
1374 		err = PTR_ERR(req);
1375 		goto error;
1376 	}
1377 
1378 	err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1379 	if (err) {
1380 		p9pdu_dump(1, req->rc);
1381 		p9_free_req(clnt, req);
1382 		goto error;
1383 	}
1384 
1385 	P9_DPRINTK(P9_DEBUG_9P,
1386 		"<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1387 		"<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1388 		"<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1389 		"<<<    uid=%d gid=%d n_muid=%d\n",
1390 		ret->size, ret->type, ret->dev, ret->qid.type,
1391 		(unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1392 		ret->atime, ret->mtime, (unsigned long long)ret->length,
1393 		ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1394 		ret->n_uid, ret->n_gid, ret->n_muid);
1395 
1396 	p9_free_req(clnt, req);
1397 	return ret;
1398 
1399 error:
1400 	kfree(ret);
1401 	return ERR_PTR(err);
1402 }
1403 EXPORT_SYMBOL(p9_client_stat);
1404 
1405 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1406 							u64 request_mask)
1407 {
1408 	int err;
1409 	struct p9_client *clnt;
1410 	struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1411 								GFP_KERNEL);
1412 	struct p9_req_t *req;
1413 
1414 	P9_DPRINTK(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1415 							fid->fid, request_mask);
1416 
1417 	if (!ret)
1418 		return ERR_PTR(-ENOMEM);
1419 
1420 	err = 0;
1421 	clnt = fid->clnt;
1422 
1423 	req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1424 	if (IS_ERR(req)) {
1425 		err = PTR_ERR(req);
1426 		goto error;
1427 	}
1428 
1429 	err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1430 	if (err) {
1431 		p9pdu_dump(1, req->rc);
1432 		p9_free_req(clnt, req);
1433 		goto error;
1434 	}
1435 
1436 	P9_DPRINTK(P9_DEBUG_9P,
1437 		"<<< RGETATTR st_result_mask=%lld\n"
1438 		"<<< qid=%x.%llx.%x\n"
1439 		"<<< st_mode=%8.8x st_nlink=%llu\n"
1440 		"<<< st_uid=%d st_gid=%d\n"
1441 		"<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1442 		"<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1443 		"<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1444 		"<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1445 		"<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1446 		"<<< st_gen=%lld st_data_version=%lld",
1447 		ret->st_result_mask, ret->qid.type, ret->qid.path,
1448 		ret->qid.version, ret->st_mode, ret->st_nlink, ret->st_uid,
1449 		ret->st_gid, ret->st_rdev, ret->st_size, ret->st_blksize,
1450 		ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1451 		ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1452 		ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1453 		ret->st_gen, ret->st_data_version);
1454 
1455 	p9_free_req(clnt, req);
1456 	return ret;
1457 
1458 error:
1459 	kfree(ret);
1460 	return ERR_PTR(err);
1461 }
1462 EXPORT_SYMBOL(p9_client_getattr_dotl);
1463 
1464 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1465 {
1466 	int ret;
1467 
1468 	/* NOTE: size shouldn't include its own length */
1469 	/* size[2] type[2] dev[4] qid[13] */
1470 	/* mode[4] atime[4] mtime[4] length[8]*/
1471 	/* name[s] uid[s] gid[s] muid[s] */
1472 	ret = 2+4+13+4+4+4+8+2+2+2+2;
1473 
1474 	if (wst->name)
1475 		ret += strlen(wst->name);
1476 	if (wst->uid)
1477 		ret += strlen(wst->uid);
1478 	if (wst->gid)
1479 		ret += strlen(wst->gid);
1480 	if (wst->muid)
1481 		ret += strlen(wst->muid);
1482 
1483 	if ((proto_version == p9_proto_2000u) ||
1484 		(proto_version == p9_proto_2000L)) {
1485 		ret += 2+4+4+4;	/* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1486 		if (wst->extension)
1487 			ret += strlen(wst->extension);
1488 	}
1489 
1490 	return ret;
1491 }
1492 
1493 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1494 {
1495 	int err;
1496 	struct p9_req_t *req;
1497 	struct p9_client *clnt;
1498 
1499 	err = 0;
1500 	clnt = fid->clnt;
1501 	wst->size = p9_client_statsize(wst, clnt->proto_version);
1502 	P9_DPRINTK(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1503 	P9_DPRINTK(P9_DEBUG_9P,
1504 		"     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1505 		"     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1506 		"     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1507 		"     uid=%d gid=%d n_muid=%d\n",
1508 		wst->size, wst->type, wst->dev, wst->qid.type,
1509 		(unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1510 		wst->atime, wst->mtime, (unsigned long long)wst->length,
1511 		wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1512 		wst->n_uid, wst->n_gid, wst->n_muid);
1513 
1514 	req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1515 	if (IS_ERR(req)) {
1516 		err = PTR_ERR(req);
1517 		goto error;
1518 	}
1519 
1520 	P9_DPRINTK(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1521 
1522 	p9_free_req(clnt, req);
1523 error:
1524 	return err;
1525 }
1526 EXPORT_SYMBOL(p9_client_wstat);
1527 
1528 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1529 {
1530 	int err;
1531 	struct p9_req_t *req;
1532 	struct p9_client *clnt;
1533 
1534 	err = 0;
1535 	clnt = fid->clnt;
1536 	P9_DPRINTK(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1537 	P9_DPRINTK(P9_DEBUG_9P,
1538 		"    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1539 		"    atime_sec=%lld atime_nsec=%lld\n"
1540 		"    mtime_sec=%lld mtime_nsec=%lld\n",
1541 		p9attr->valid, p9attr->mode, p9attr->uid, p9attr->gid,
1542 		p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1543 		p9attr->mtime_sec, p9attr->mtime_nsec);
1544 
1545 	req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1546 
1547 	if (IS_ERR(req)) {
1548 		err = PTR_ERR(req);
1549 		goto error;
1550 	}
1551 	P9_DPRINTK(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1552 	p9_free_req(clnt, req);
1553 error:
1554 	return err;
1555 }
1556 EXPORT_SYMBOL(p9_client_setattr);
1557 
1558 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1559 {
1560 	int err;
1561 	struct p9_req_t *req;
1562 	struct p9_client *clnt;
1563 
1564 	err = 0;
1565 	clnt = fid->clnt;
1566 
1567 	P9_DPRINTK(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1568 
1569 	req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1570 	if (IS_ERR(req)) {
1571 		err = PTR_ERR(req);
1572 		goto error;
1573 	}
1574 
1575 	err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1576 		&sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1577 		&sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1578 	if (err) {
1579 		p9pdu_dump(1, req->rc);
1580 		p9_free_req(clnt, req);
1581 		goto error;
1582 	}
1583 
1584 	P9_DPRINTK(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1585 		"blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1586 		"fsid %llu namelen %ld\n",
1587 		fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1588 		sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1589 		sb->fsid, (long int)sb->namelen);
1590 
1591 	p9_free_req(clnt, req);
1592 error:
1593 	return err;
1594 }
1595 EXPORT_SYMBOL(p9_client_statfs);
1596 
1597 int p9_client_rename(struct p9_fid *fid, struct p9_fid *newdirfid, char *name)
1598 {
1599 	int err;
1600 	struct p9_req_t *req;
1601 	struct p9_client *clnt;
1602 
1603 	err = 0;
1604 	clnt = fid->clnt;
1605 
1606 	P9_DPRINTK(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1607 			fid->fid, newdirfid->fid, name);
1608 
1609 	req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1610 			newdirfid->fid, name);
1611 	if (IS_ERR(req)) {
1612 		err = PTR_ERR(req);
1613 		goto error;
1614 	}
1615 
1616 	P9_DPRINTK(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1617 
1618 	p9_free_req(clnt, req);
1619 error:
1620 	return err;
1621 }
1622 EXPORT_SYMBOL(p9_client_rename);
1623 
1624 /*
1625  * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1626  */
1627 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1628 				const char *attr_name, u64 *attr_size)
1629 {
1630 	int err;
1631 	struct p9_req_t *req;
1632 	struct p9_client *clnt;
1633 	struct p9_fid *attr_fid;
1634 
1635 	err = 0;
1636 	clnt = file_fid->clnt;
1637 	attr_fid = p9_fid_create(clnt);
1638 	if (IS_ERR(attr_fid)) {
1639 		err = PTR_ERR(attr_fid);
1640 		attr_fid = NULL;
1641 		goto error;
1642 	}
1643 	P9_DPRINTK(P9_DEBUG_9P,
1644 		">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
1645 		file_fid->fid, attr_fid->fid, attr_name);
1646 
1647 	req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
1648 			file_fid->fid, attr_fid->fid, attr_name);
1649 	if (IS_ERR(req)) {
1650 		err = PTR_ERR(req);
1651 		goto error;
1652 	}
1653 	err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
1654 	if (err) {
1655 		p9pdu_dump(1, req->rc);
1656 		p9_free_req(clnt, req);
1657 		goto clunk_fid;
1658 	}
1659 	p9_free_req(clnt, req);
1660 	P9_DPRINTK(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
1661 		attr_fid->fid, *attr_size);
1662 	return attr_fid;
1663 clunk_fid:
1664 	p9_client_clunk(attr_fid);
1665 	attr_fid = NULL;
1666 error:
1667 	if (attr_fid && (attr_fid != file_fid))
1668 		p9_fid_destroy(attr_fid);
1669 
1670 	return ERR_PTR(err);
1671 }
1672 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
1673 
1674 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
1675 			u64 attr_size, int flags)
1676 {
1677 	int err;
1678 	struct p9_req_t *req;
1679 	struct p9_client *clnt;
1680 
1681 	P9_DPRINTK(P9_DEBUG_9P,
1682 		">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
1683 		fid->fid, name, (long long)attr_size, flags);
1684 	err = 0;
1685 	clnt = fid->clnt;
1686 	req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
1687 			fid->fid, name, attr_size, flags);
1688 	if (IS_ERR(req)) {
1689 		err = PTR_ERR(req);
1690 		goto error;
1691 	}
1692 	P9_DPRINTK(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
1693 	p9_free_req(clnt, req);
1694 error:
1695 	return err;
1696 }
1697 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
1698 
1699 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
1700 {
1701 	int err, rsize, total;
1702 	struct p9_client *clnt;
1703 	struct p9_req_t *req;
1704 	char *dataptr;
1705 
1706 	P9_DPRINTK(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
1707 				fid->fid, (long long unsigned) offset, count);
1708 
1709 	err = 0;
1710 	clnt = fid->clnt;
1711 	total = 0;
1712 
1713 	rsize = fid->iounit;
1714 	if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
1715 		rsize = clnt->msize - P9_READDIRHDRSZ;
1716 
1717 	if (count < rsize)
1718 		rsize = count;
1719 
1720 	req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid, offset, rsize);
1721 	if (IS_ERR(req)) {
1722 		err = PTR_ERR(req);
1723 		goto error;
1724 	}
1725 
1726 	err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1727 	if (err) {
1728 		p9pdu_dump(1, req->rc);
1729 		goto free_and_error;
1730 	}
1731 
1732 	P9_DPRINTK(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
1733 
1734 	if (data)
1735 		memmove(data, dataptr, count);
1736 
1737 	p9_free_req(clnt, req);
1738 	return count;
1739 
1740 free_and_error:
1741 	p9_free_req(clnt, req);
1742 error:
1743 	return err;
1744 }
1745 EXPORT_SYMBOL(p9_client_readdir);
1746 
1747 int p9_client_mknod_dotl(struct p9_fid *fid, char *name, int mode,
1748 			dev_t rdev, gid_t gid, struct p9_qid *qid)
1749 {
1750 	int err;
1751 	struct p9_client *clnt;
1752 	struct p9_req_t *req;
1753 
1754 	err = 0;
1755 	clnt = fid->clnt;
1756 	P9_DPRINTK(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
1757 		"minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
1758 	req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddd", fid->fid, name, mode,
1759 		MAJOR(rdev), MINOR(rdev), gid);
1760 	if (IS_ERR(req))
1761 		return PTR_ERR(req);
1762 
1763 	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1764 	if (err) {
1765 		p9pdu_dump(1, req->rc);
1766 		goto error;
1767 	}
1768 	P9_DPRINTK(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
1769 				(unsigned long long)qid->path, qid->version);
1770 
1771 error:
1772 	p9_free_req(clnt, req);
1773 	return err;
1774 
1775 }
1776 EXPORT_SYMBOL(p9_client_mknod_dotl);
1777 
1778 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
1779 				gid_t gid, struct p9_qid *qid)
1780 {
1781 	int err;
1782 	struct p9_client *clnt;
1783 	struct p9_req_t *req;
1784 
1785 	err = 0;
1786 	clnt = fid->clnt;
1787 	P9_DPRINTK(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
1788 		 fid->fid, name, mode, gid);
1789 	req = p9_client_rpc(clnt, P9_TMKDIR, "dsdd", fid->fid, name, mode,
1790 		gid);
1791 	if (IS_ERR(req))
1792 		return PTR_ERR(req);
1793 
1794 	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1795 	if (err) {
1796 		p9pdu_dump(1, req->rc);
1797 		goto error;
1798 	}
1799 	P9_DPRINTK(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
1800 				(unsigned long long)qid->path, qid->version);
1801 
1802 error:
1803 	p9_free_req(clnt, req);
1804 	return err;
1805 
1806 }
1807 EXPORT_SYMBOL(p9_client_mkdir_dotl);
1808