xref: /openbmc/linux/net/9p/client.c (revision d5532ee7)
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_put(0, c->tagpool); /* free reserved tag 0 */
336 		p9_idpool_destroy(c->tagpool);
337 	}
338 
339 	/* free requests associated with tags */
340 	for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
341 		for (col = 0; col < P9_ROW_MAXTAG; col++) {
342 			kfree(c->reqs[row][col].wq);
343 			kfree(c->reqs[row][col].tc);
344 			kfree(c->reqs[row][col].rc);
345 		}
346 		kfree(c->reqs[row]);
347 	}
348 	c->max_tag = 0;
349 }
350 
351 /**
352  * p9_free_req - free a request and clean-up as necessary
353  * c: client state
354  * r: request to release
355  *
356  */
357 
358 static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
359 {
360 	int tag = r->tc->tag;
361 	P9_DPRINTK(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
362 
363 	r->status = REQ_STATUS_IDLE;
364 	if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
365 		p9_idpool_put(tag, c->tagpool);
366 }
367 
368 /**
369  * p9_client_cb - call back from transport to client
370  * c: client state
371  * req: request received
372  *
373  */
374 void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
375 {
376 	P9_DPRINTK(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
377 	wake_up(req->wq);
378 	P9_DPRINTK(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
379 }
380 EXPORT_SYMBOL(p9_client_cb);
381 
382 /**
383  * p9_parse_header - parse header arguments out of a packet
384  * @pdu: packet to parse
385  * @size: size of packet
386  * @type: type of request
387  * @tag: tag of packet
388  * @rewind: set if we need to rewind offset afterwards
389  */
390 
391 int
392 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
393 								int rewind)
394 {
395 	int8_t r_type;
396 	int16_t r_tag;
397 	int32_t r_size;
398 	int offset = pdu->offset;
399 	int err;
400 
401 	pdu->offset = 0;
402 	if (pdu->size == 0)
403 		pdu->size = 7;
404 
405 	err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
406 	if (err)
407 		goto rewind_and_exit;
408 
409 	pdu->size = r_size;
410 	pdu->id = r_type;
411 	pdu->tag = r_tag;
412 
413 	P9_DPRINTK(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n", pdu->size,
414 							pdu->id, pdu->tag);
415 
416 	if (type)
417 		*type = r_type;
418 	if (tag)
419 		*tag = r_tag;
420 	if (size)
421 		*size = r_size;
422 
423 
424 rewind_and_exit:
425 	if (rewind)
426 		pdu->offset = offset;
427 	return err;
428 }
429 EXPORT_SYMBOL(p9_parse_header);
430 
431 /**
432  * p9_check_errors - check 9p packet for error return and process it
433  * @c: current client instance
434  * @req: request to parse and check for error conditions
435  *
436  * returns error code if one is discovered, otherwise returns 0
437  *
438  * this will have to be more complicated if we have multiple
439  * error packet types
440  */
441 
442 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
443 {
444 	int8_t type;
445 	int err;
446 
447 	err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
448 	if (err) {
449 		P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
450 		return err;
451 	}
452 
453 	if (type == P9_RERROR) {
454 		int ecode;
455 		char *ename;
456 
457 		err = p9pdu_readf(req->rc, c->proto_version, "s?d",
458 							&ename, &ecode);
459 		if (err) {
460 			P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n",
461 									err);
462 			return err;
463 		}
464 
465 		if (p9_is_proto_dotu(c) ||
466 			p9_is_proto_dotl(c))
467 			err = -ecode;
468 
469 		if (!err || !IS_ERR_VALUE(err))
470 			err = p9_errstr2errno(ename, strlen(ename));
471 
472 		P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
473 
474 		kfree(ename);
475 	} else
476 		err = 0;
477 
478 	return err;
479 }
480 
481 /**
482  * p9_client_flush - flush (cancel) a request
483  * @c: client state
484  * @oldreq: request to cancel
485  *
486  * This sents a flush for a particular requests and links
487  * the flush request to the original request.  The current
488  * code only supports a single flush request although the protocol
489  * allows for multiple flush requests to be sent for a single request.
490  *
491  */
492 
493 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
494 {
495 	struct p9_req_t *req;
496 	int16_t oldtag;
497 	int err;
498 
499 	err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
500 	if (err)
501 		return err;
502 
503 	P9_DPRINTK(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
504 
505 	req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
506 	if (IS_ERR(req))
507 		return PTR_ERR(req);
508 
509 
510 	/* if we haven't received a response for oldreq,
511 	   remove it from the list. */
512 	spin_lock(&c->lock);
513 	if (oldreq->status == REQ_STATUS_FLSH)
514 		list_del(&oldreq->req_list);
515 	spin_unlock(&c->lock);
516 
517 	p9_free_req(c, req);
518 	return 0;
519 }
520 
521 /**
522  * p9_client_rpc - issue a request and wait for a response
523  * @c: client session
524  * @type: type of request
525  * @fmt: protocol format string (see protocol.c)
526  *
527  * Returns request structure (which client must free using p9_free_req)
528  */
529 
530 static struct p9_req_t *
531 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
532 {
533 	va_list ap;
534 	int tag, err;
535 	struct p9_req_t *req;
536 	unsigned long flags;
537 	int sigpending;
538 
539 	P9_DPRINTK(P9_DEBUG_MUX, "client %p op %d\n", c, type);
540 
541 	/* we allow for any status other than disconnected */
542 	if (c->status == Disconnected)
543 		return ERR_PTR(-EIO);
544 
545 	/* if status is begin_disconnected we allow only clunk request */
546 	if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
547 		return ERR_PTR(-EIO);
548 
549 	if (signal_pending(current)) {
550 		sigpending = 1;
551 		clear_thread_flag(TIF_SIGPENDING);
552 	} else
553 		sigpending = 0;
554 
555 	tag = P9_NOTAG;
556 	if (type != P9_TVERSION) {
557 		tag = p9_idpool_get(c->tagpool);
558 		if (tag < 0)
559 			return ERR_PTR(-ENOMEM);
560 	}
561 
562 	req = p9_tag_alloc(c, tag);
563 	if (IS_ERR(req))
564 		return req;
565 
566 	/* marshall the data */
567 	p9pdu_prepare(req->tc, tag, type);
568 	va_start(ap, fmt);
569 	err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
570 	va_end(ap);
571 	p9pdu_finalize(req->tc);
572 
573 	err = c->trans_mod->request(c, req);
574 	if (err < 0) {
575 		c->status = Disconnected;
576 		goto reterr;
577 	}
578 
579 	P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d\n", req->wq, tag);
580 	err = wait_event_interruptible(*req->wq,
581 						req->status >= REQ_STATUS_RCVD);
582 	P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d returned %d\n",
583 						req->wq, tag, err);
584 
585 	if (req->status == REQ_STATUS_ERROR) {
586 		P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
587 		err = req->t_err;
588 	}
589 
590 	if ((err == -ERESTARTSYS) && (c->status == Connected)) {
591 		P9_DPRINTK(P9_DEBUG_MUX, "flushing\n");
592 		sigpending = 1;
593 		clear_thread_flag(TIF_SIGPENDING);
594 
595 		if (c->trans_mod->cancel(c, req))
596 			p9_client_flush(c, req);
597 
598 		/* if we received the response anyway, don't signal error */
599 		if (req->status == REQ_STATUS_RCVD)
600 			err = 0;
601 	}
602 
603 	if (sigpending) {
604 		spin_lock_irqsave(&current->sighand->siglock, flags);
605 		recalc_sigpending();
606 		spin_unlock_irqrestore(&current->sighand->siglock, flags);
607 	}
608 
609 	if (err < 0)
610 		goto reterr;
611 
612 	err = p9_check_errors(c, req);
613 	if (!err) {
614 		P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d\n", c, type);
615 		return req;
616 	}
617 
618 reterr:
619 	P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d error: %d\n", c, type,
620 									err);
621 	p9_free_req(c, req);
622 	return ERR_PTR(err);
623 }
624 
625 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
626 {
627 	int ret;
628 	struct p9_fid *fid;
629 	unsigned long flags;
630 
631 	P9_DPRINTK(P9_DEBUG_FID, "clnt %p\n", clnt);
632 	fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
633 	if (!fid)
634 		return ERR_PTR(-ENOMEM);
635 
636 	ret = p9_idpool_get(clnt->fidpool);
637 	if (ret < 0) {
638 		ret = -ENOSPC;
639 		goto error;
640 	}
641 	fid->fid = ret;
642 
643 	memset(&fid->qid, 0, sizeof(struct p9_qid));
644 	fid->mode = -1;
645 	fid->uid = current_fsuid();
646 	fid->clnt = clnt;
647 	fid->rdir = NULL;
648 	spin_lock_irqsave(&clnt->lock, flags);
649 	list_add(&fid->flist, &clnt->fidlist);
650 	spin_unlock_irqrestore(&clnt->lock, flags);
651 
652 	return fid;
653 
654 error:
655 	kfree(fid);
656 	return ERR_PTR(ret);
657 }
658 
659 static void p9_fid_destroy(struct p9_fid *fid)
660 {
661 	struct p9_client *clnt;
662 	unsigned long flags;
663 
664 	P9_DPRINTK(P9_DEBUG_FID, "fid %d\n", fid->fid);
665 	clnt = fid->clnt;
666 	p9_idpool_put(fid->fid, clnt->fidpool);
667 	spin_lock_irqsave(&clnt->lock, flags);
668 	list_del(&fid->flist);
669 	spin_unlock_irqrestore(&clnt->lock, flags);
670 	kfree(fid->rdir);
671 	kfree(fid);
672 }
673 
674 int p9_client_version(struct p9_client *c)
675 {
676 	int err = 0;
677 	struct p9_req_t *req;
678 	char *version;
679 	int msize;
680 
681 	P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
682 						c->msize, c->proto_version);
683 
684 	switch (c->proto_version) {
685 	case p9_proto_2000L:
686 		req = p9_client_rpc(c, P9_TVERSION, "ds",
687 					c->msize, "9P2000.L");
688 		break;
689 	case p9_proto_2000u:
690 		req = p9_client_rpc(c, P9_TVERSION, "ds",
691 					c->msize, "9P2000.u");
692 		break;
693 	case p9_proto_legacy:
694 		req = p9_client_rpc(c, P9_TVERSION, "ds",
695 					c->msize, "9P2000");
696 		break;
697 	default:
698 		return -EINVAL;
699 		break;
700 	}
701 
702 	if (IS_ERR(req))
703 		return PTR_ERR(req);
704 
705 	err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
706 	if (err) {
707 		P9_DPRINTK(P9_DEBUG_9P, "version error %d\n", err);
708 		p9pdu_dump(1, req->rc);
709 		goto error;
710 	}
711 
712 	P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
713 	if (!strncmp(version, "9P2000.L", 8))
714 		c->proto_version = p9_proto_2000L;
715 	else if (!strncmp(version, "9P2000.u", 8))
716 		c->proto_version = p9_proto_2000u;
717 	else if (!strncmp(version, "9P2000", 6))
718 		c->proto_version = p9_proto_legacy;
719 	else {
720 		err = -EREMOTEIO;
721 		goto error;
722 	}
723 
724 	if (msize < c->msize)
725 		c->msize = msize;
726 
727 error:
728 	kfree(version);
729 	p9_free_req(c, req);
730 
731 	return err;
732 }
733 EXPORT_SYMBOL(p9_client_version);
734 
735 struct p9_client *p9_client_create(const char *dev_name, char *options)
736 {
737 	int err;
738 	struct p9_client *clnt;
739 
740 	err = 0;
741 	clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
742 	if (!clnt)
743 		return ERR_PTR(-ENOMEM);
744 
745 	clnt->trans_mod = NULL;
746 	clnt->trans = NULL;
747 	spin_lock_init(&clnt->lock);
748 	INIT_LIST_HEAD(&clnt->fidlist);
749 
750 	p9_tag_init(clnt);
751 
752 	err = parse_opts(options, clnt);
753 	if (err < 0)
754 		goto free_client;
755 
756 	if (!clnt->trans_mod)
757 		clnt->trans_mod = v9fs_get_default_trans();
758 
759 	if (clnt->trans_mod == NULL) {
760 		err = -EPROTONOSUPPORT;
761 		P9_DPRINTK(P9_DEBUG_ERROR,
762 				"No transport defined or default transport\n");
763 		goto free_client;
764 	}
765 
766 	clnt->fidpool = p9_idpool_create();
767 	if (IS_ERR(clnt->fidpool)) {
768 		err = PTR_ERR(clnt->fidpool);
769 		clnt->fidpool = NULL;
770 		goto put_trans;
771 	}
772 
773 	P9_DPRINTK(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
774 		clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
775 
776 	err = clnt->trans_mod->create(clnt, dev_name, options);
777 	if (err)
778 		goto destroy_fidpool;
779 
780 	if ((clnt->msize+P9_IOHDRSZ) > clnt->trans_mod->maxsize)
781 		clnt->msize = clnt->trans_mod->maxsize-P9_IOHDRSZ;
782 
783 	err = p9_client_version(clnt);
784 	if (err)
785 		goto close_trans;
786 
787 	return clnt;
788 
789 close_trans:
790 	clnt->trans_mod->close(clnt);
791 destroy_fidpool:
792 	p9_idpool_destroy(clnt->fidpool);
793 put_trans:
794 	v9fs_put_trans(clnt->trans_mod);
795 free_client:
796 	kfree(clnt);
797 	return ERR_PTR(err);
798 }
799 EXPORT_SYMBOL(p9_client_create);
800 
801 void p9_client_destroy(struct p9_client *clnt)
802 {
803 	struct p9_fid *fid, *fidptr;
804 
805 	P9_DPRINTK(P9_DEBUG_MUX, "clnt %p\n", clnt);
806 
807 	if (clnt->trans_mod)
808 		clnt->trans_mod->close(clnt);
809 
810 	v9fs_put_trans(clnt->trans_mod);
811 
812 	list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
813 		printk(KERN_INFO "Found fid %d not clunked\n", fid->fid);
814 		p9_fid_destroy(fid);
815 	}
816 
817 	if (clnt->fidpool)
818 		p9_idpool_destroy(clnt->fidpool);
819 
820 	p9_tag_cleanup(clnt);
821 
822 	kfree(clnt);
823 }
824 EXPORT_SYMBOL(p9_client_destroy);
825 
826 void p9_client_disconnect(struct p9_client *clnt)
827 {
828 	P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
829 	clnt->status = Disconnected;
830 }
831 EXPORT_SYMBOL(p9_client_disconnect);
832 
833 void p9_client_begin_disconnect(struct p9_client *clnt)
834 {
835 	P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
836 	clnt->status = BeginDisconnect;
837 }
838 EXPORT_SYMBOL(p9_client_begin_disconnect);
839 
840 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
841 	char *uname, u32 n_uname, char *aname)
842 {
843 	int err;
844 	struct p9_req_t *req;
845 	struct p9_fid *fid;
846 	struct p9_qid qid;
847 
848 	P9_DPRINTK(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
849 					afid ? afid->fid : -1, uname, aname);
850 	err = 0;
851 
852 	fid = p9_fid_create(clnt);
853 	if (IS_ERR(fid)) {
854 		err = PTR_ERR(fid);
855 		fid = NULL;
856 		goto error;
857 	}
858 
859 	req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
860 			afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
861 	if (IS_ERR(req)) {
862 		err = PTR_ERR(req);
863 		goto error;
864 	}
865 
866 	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
867 	if (err) {
868 		p9pdu_dump(1, req->rc);
869 		p9_free_req(clnt, req);
870 		goto error;
871 	}
872 
873 	P9_DPRINTK(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
874 					qid.type,
875 					(unsigned long long)qid.path,
876 					qid.version);
877 
878 	memmove(&fid->qid, &qid, sizeof(struct p9_qid));
879 
880 	p9_free_req(clnt, req);
881 	return fid;
882 
883 error:
884 	if (fid)
885 		p9_fid_destroy(fid);
886 	return ERR_PTR(err);
887 }
888 EXPORT_SYMBOL(p9_client_attach);
889 
890 struct p9_fid *
891 p9_client_auth(struct p9_client *clnt, char *uname, u32 n_uname, char *aname)
892 {
893 	int err;
894 	struct p9_req_t *req;
895 	struct p9_qid qid;
896 	struct p9_fid *afid;
897 
898 	P9_DPRINTK(P9_DEBUG_9P, ">>> TAUTH uname %s aname %s\n", uname, aname);
899 	err = 0;
900 
901 	afid = p9_fid_create(clnt);
902 	if (IS_ERR(afid)) {
903 		err = PTR_ERR(afid);
904 		afid = NULL;
905 		goto error;
906 	}
907 
908 	req = p9_client_rpc(clnt, P9_TAUTH, "dss?d",
909 			afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
910 	if (IS_ERR(req)) {
911 		err = PTR_ERR(req);
912 		goto error;
913 	}
914 
915 	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
916 	if (err) {
917 		p9pdu_dump(1, req->rc);
918 		p9_free_req(clnt, req);
919 		goto error;
920 	}
921 
922 	P9_DPRINTK(P9_DEBUG_9P, "<<< RAUTH qid %x.%llx.%x\n",
923 					qid.type,
924 					(unsigned long long)qid.path,
925 					qid.version);
926 
927 	memmove(&afid->qid, &qid, sizeof(struct p9_qid));
928 	p9_free_req(clnt, req);
929 	return afid;
930 
931 error:
932 	if (afid)
933 		p9_fid_destroy(afid);
934 	return ERR_PTR(err);
935 }
936 EXPORT_SYMBOL(p9_client_auth);
937 
938 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, int nwname, char **wnames,
939 	int clone)
940 {
941 	int err;
942 	struct p9_client *clnt;
943 	struct p9_fid *fid;
944 	struct p9_qid *wqids;
945 	struct p9_req_t *req;
946 	int16_t nwqids, count;
947 
948 	err = 0;
949 	wqids = NULL;
950 	clnt = oldfid->clnt;
951 	if (clone) {
952 		fid = p9_fid_create(clnt);
953 		if (IS_ERR(fid)) {
954 			err = PTR_ERR(fid);
955 			fid = NULL;
956 			goto error;
957 		}
958 
959 		fid->uid = oldfid->uid;
960 	} else
961 		fid = oldfid;
962 
963 
964 	P9_DPRINTK(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %d wname[0] %s\n",
965 		oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
966 
967 	req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
968 								nwname, wnames);
969 	if (IS_ERR(req)) {
970 		err = PTR_ERR(req);
971 		goto error;
972 	}
973 
974 	err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
975 	if (err) {
976 		p9pdu_dump(1, req->rc);
977 		p9_free_req(clnt, req);
978 		goto clunk_fid;
979 	}
980 	p9_free_req(clnt, req);
981 
982 	P9_DPRINTK(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
983 
984 	if (nwqids != nwname) {
985 		err = -ENOENT;
986 		goto clunk_fid;
987 	}
988 
989 	for (count = 0; count < nwqids; count++)
990 		P9_DPRINTK(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
991 			count, wqids[count].type,
992 			(unsigned long long)wqids[count].path,
993 			wqids[count].version);
994 
995 	if (nwname)
996 		memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
997 	else
998 		fid->qid = oldfid->qid;
999 
1000 	kfree(wqids);
1001 	return fid;
1002 
1003 clunk_fid:
1004 	kfree(wqids);
1005 	p9_client_clunk(fid);
1006 	fid = NULL;
1007 
1008 error:
1009 	if (fid && (fid != oldfid))
1010 		p9_fid_destroy(fid);
1011 
1012 	return ERR_PTR(err);
1013 }
1014 EXPORT_SYMBOL(p9_client_walk);
1015 
1016 int p9_client_open(struct p9_fid *fid, int mode)
1017 {
1018 	int err;
1019 	struct p9_client *clnt;
1020 	struct p9_req_t *req;
1021 	struct p9_qid qid;
1022 	int iounit;
1023 
1024 	clnt = fid->clnt;
1025 	P9_DPRINTK(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1026 		p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1027 	err = 0;
1028 
1029 	if (fid->mode != -1)
1030 		return -EINVAL;
1031 
1032 	if (p9_is_proto_dotl(clnt))
1033 		req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1034 	else
1035 		req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
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, "<<< %s qid %x.%llx.%x iounit %x\n",
1048 		p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1049 		(unsigned long long)qid.path, qid.version, iounit);
1050 
1051 	fid->mode = mode;
1052 	fid->iounit = iounit;
1053 
1054 free_and_error:
1055 	p9_free_req(clnt, req);
1056 error:
1057 	return err;
1058 }
1059 EXPORT_SYMBOL(p9_client_open);
1060 
1061 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
1062 		gid_t gid, struct p9_qid *qid)
1063 {
1064 	int err = 0;
1065 	struct p9_client *clnt;
1066 	struct p9_req_t *req;
1067 	int iounit;
1068 
1069 	P9_DPRINTK(P9_DEBUG_9P,
1070 			">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1071 			ofid->fid, name, flags, mode, gid);
1072 	clnt = ofid->clnt;
1073 
1074 	if (ofid->mode != -1)
1075 		return -EINVAL;
1076 
1077 	req = p9_client_rpc(clnt, P9_TLCREATE, "dsddd", ofid->fid, name, flags,
1078 			mode, gid);
1079 	if (IS_ERR(req)) {
1080 		err = PTR_ERR(req);
1081 		goto error;
1082 	}
1083 
1084 	err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1085 	if (err) {
1086 		p9pdu_dump(1, req->rc);
1087 		goto free_and_error;
1088 	}
1089 
1090 	P9_DPRINTK(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1091 			qid->type,
1092 			(unsigned long long)qid->path,
1093 			qid->version, iounit);
1094 
1095 	ofid->mode = mode;
1096 	ofid->iounit = iounit;
1097 
1098 free_and_error:
1099 	p9_free_req(clnt, req);
1100 error:
1101 	return err;
1102 }
1103 EXPORT_SYMBOL(p9_client_create_dotl);
1104 
1105 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1106 		     char *extension)
1107 {
1108 	int err;
1109 	struct p9_client *clnt;
1110 	struct p9_req_t *req;
1111 	struct p9_qid qid;
1112 	int iounit;
1113 
1114 	P9_DPRINTK(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1115 						fid->fid, name, perm, mode);
1116 	err = 0;
1117 	clnt = fid->clnt;
1118 
1119 	if (fid->mode != -1)
1120 		return -EINVAL;
1121 
1122 	req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1123 				mode, extension);
1124 	if (IS_ERR(req)) {
1125 		err = PTR_ERR(req);
1126 		goto error;
1127 	}
1128 
1129 	err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1130 	if (err) {
1131 		p9pdu_dump(1, req->rc);
1132 		goto free_and_error;
1133 	}
1134 
1135 	P9_DPRINTK(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1136 				qid.type,
1137 				(unsigned long long)qid.path,
1138 				qid.version, iounit);
1139 
1140 	fid->mode = mode;
1141 	fid->iounit = iounit;
1142 
1143 free_and_error:
1144 	p9_free_req(clnt, req);
1145 error:
1146 	return err;
1147 }
1148 EXPORT_SYMBOL(p9_client_fcreate);
1149 
1150 int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, gid_t gid,
1151 		struct p9_qid *qid)
1152 {
1153 	int err = 0;
1154 	struct p9_client *clnt;
1155 	struct p9_req_t *req;
1156 
1157 	P9_DPRINTK(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1158 			dfid->fid, name, symtgt);
1159 	clnt = dfid->clnt;
1160 
1161 	req = p9_client_rpc(clnt, P9_TSYMLINK, "dssd", dfid->fid, name, symtgt,
1162 			gid);
1163 	if (IS_ERR(req)) {
1164 		err = PTR_ERR(req);
1165 		goto error;
1166 	}
1167 
1168 	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1169 	if (err) {
1170 		p9pdu_dump(1, req->rc);
1171 		goto free_and_error;
1172 	}
1173 
1174 	P9_DPRINTK(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1175 			qid->type, (unsigned long long)qid->path, qid->version);
1176 
1177 free_and_error:
1178 	p9_free_req(clnt, req);
1179 error:
1180 	return err;
1181 }
1182 EXPORT_SYMBOL(p9_client_symlink);
1183 
1184 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
1185 {
1186 	struct p9_client *clnt;
1187 	struct p9_req_t *req;
1188 
1189 	P9_DPRINTK(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1190 			dfid->fid, oldfid->fid, newname);
1191 	clnt = dfid->clnt;
1192 	req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1193 			newname);
1194 	if (IS_ERR(req))
1195 		return PTR_ERR(req);
1196 
1197 	P9_DPRINTK(P9_DEBUG_9P, "<<< RLINK\n");
1198 	p9_free_req(clnt, req);
1199 	return 0;
1200 }
1201 EXPORT_SYMBOL(p9_client_link);
1202 
1203 int p9_client_clunk(struct p9_fid *fid)
1204 {
1205 	int err;
1206 	struct p9_client *clnt;
1207 	struct p9_req_t *req;
1208 
1209 	P9_DPRINTK(P9_DEBUG_9P, ">>> TCLUNK fid %d\n", fid->fid);
1210 	err = 0;
1211 	clnt = fid->clnt;
1212 
1213 	req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1214 	if (IS_ERR(req)) {
1215 		err = PTR_ERR(req);
1216 		goto error;
1217 	}
1218 
1219 	P9_DPRINTK(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1220 
1221 	p9_free_req(clnt, req);
1222 	p9_fid_destroy(fid);
1223 
1224 error:
1225 	return err;
1226 }
1227 EXPORT_SYMBOL(p9_client_clunk);
1228 
1229 int p9_client_remove(struct p9_fid *fid)
1230 {
1231 	int err;
1232 	struct p9_client *clnt;
1233 	struct p9_req_t *req;
1234 
1235 	P9_DPRINTK(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1236 	err = 0;
1237 	clnt = fid->clnt;
1238 
1239 	req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1240 	if (IS_ERR(req)) {
1241 		err = PTR_ERR(req);
1242 		goto error;
1243 	}
1244 
1245 	P9_DPRINTK(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1246 
1247 	p9_free_req(clnt, req);
1248 error:
1249 	p9_fid_destroy(fid);
1250 	return err;
1251 }
1252 EXPORT_SYMBOL(p9_client_remove);
1253 
1254 int
1255 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1256 								u32 count)
1257 {
1258 	int err, rsize, total;
1259 	struct p9_client *clnt;
1260 	struct p9_req_t *req;
1261 	char *dataptr;
1262 
1263 	P9_DPRINTK(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n", fid->fid,
1264 					(long long unsigned) offset, count);
1265 	err = 0;
1266 	clnt = fid->clnt;
1267 	total = 0;
1268 
1269 	rsize = fid->iounit;
1270 	if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1271 		rsize = clnt->msize - P9_IOHDRSZ;
1272 
1273 	if (count < rsize)
1274 		rsize = count;
1275 
1276 	req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset, rsize);
1277 	if (IS_ERR(req)) {
1278 		err = PTR_ERR(req);
1279 		goto error;
1280 	}
1281 
1282 	err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1283 	if (err) {
1284 		p9pdu_dump(1, req->rc);
1285 		goto free_and_error;
1286 	}
1287 
1288 	P9_DPRINTK(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1289 
1290 	if (data) {
1291 		memmove(data, dataptr, count);
1292 	}
1293 
1294 	if (udata) {
1295 		err = copy_to_user(udata, dataptr, count);
1296 		if (err) {
1297 			err = -EFAULT;
1298 			goto free_and_error;
1299 		}
1300 	}
1301 
1302 	p9_free_req(clnt, req);
1303 	return count;
1304 
1305 free_and_error:
1306 	p9_free_req(clnt, req);
1307 error:
1308 	return err;
1309 }
1310 EXPORT_SYMBOL(p9_client_read);
1311 
1312 int
1313 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1314 							u64 offset, u32 count)
1315 {
1316 	int err, rsize, total;
1317 	struct p9_client *clnt;
1318 	struct p9_req_t *req;
1319 
1320 	P9_DPRINTK(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1321 				fid->fid, (long long unsigned) offset, count);
1322 	err = 0;
1323 	clnt = fid->clnt;
1324 	total = 0;
1325 
1326 	rsize = fid->iounit;
1327 	if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1328 		rsize = clnt->msize - P9_IOHDRSZ;
1329 
1330 	if (count < rsize)
1331 		rsize = count;
1332 	if (data)
1333 		req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid, offset,
1334 								rsize, data);
1335 	else
1336 		req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid, offset,
1337 								rsize, udata);
1338 	if (IS_ERR(req)) {
1339 		err = PTR_ERR(req);
1340 		goto error;
1341 	}
1342 
1343 	err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1344 	if (err) {
1345 		p9pdu_dump(1, req->rc);
1346 		goto free_and_error;
1347 	}
1348 
1349 	P9_DPRINTK(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1350 
1351 	p9_free_req(clnt, req);
1352 	return count;
1353 
1354 free_and_error:
1355 	p9_free_req(clnt, req);
1356 error:
1357 	return err;
1358 }
1359 EXPORT_SYMBOL(p9_client_write);
1360 
1361 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1362 {
1363 	int err;
1364 	struct p9_client *clnt;
1365 	struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1366 	struct p9_req_t *req;
1367 	u16 ignored;
1368 
1369 	P9_DPRINTK(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1370 
1371 	if (!ret)
1372 		return ERR_PTR(-ENOMEM);
1373 
1374 	err = 0;
1375 	clnt = fid->clnt;
1376 
1377 	req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1378 	if (IS_ERR(req)) {
1379 		err = PTR_ERR(req);
1380 		goto error;
1381 	}
1382 
1383 	err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1384 	if (err) {
1385 		p9pdu_dump(1, req->rc);
1386 		p9_free_req(clnt, req);
1387 		goto error;
1388 	}
1389 
1390 	P9_DPRINTK(P9_DEBUG_9P,
1391 		"<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1392 		"<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1393 		"<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1394 		"<<<    uid=%d gid=%d n_muid=%d\n",
1395 		ret->size, ret->type, ret->dev, ret->qid.type,
1396 		(unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1397 		ret->atime, ret->mtime, (unsigned long long)ret->length,
1398 		ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1399 		ret->n_uid, ret->n_gid, ret->n_muid);
1400 
1401 	p9_free_req(clnt, req);
1402 	return ret;
1403 
1404 error:
1405 	kfree(ret);
1406 	return ERR_PTR(err);
1407 }
1408 EXPORT_SYMBOL(p9_client_stat);
1409 
1410 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1411 							u64 request_mask)
1412 {
1413 	int err;
1414 	struct p9_client *clnt;
1415 	struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1416 								GFP_KERNEL);
1417 	struct p9_req_t *req;
1418 
1419 	P9_DPRINTK(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1420 							fid->fid, request_mask);
1421 
1422 	if (!ret)
1423 		return ERR_PTR(-ENOMEM);
1424 
1425 	err = 0;
1426 	clnt = fid->clnt;
1427 
1428 	req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1429 	if (IS_ERR(req)) {
1430 		err = PTR_ERR(req);
1431 		goto error;
1432 	}
1433 
1434 	err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1435 	if (err) {
1436 		p9pdu_dump(1, req->rc);
1437 		p9_free_req(clnt, req);
1438 		goto error;
1439 	}
1440 
1441 	P9_DPRINTK(P9_DEBUG_9P,
1442 		"<<< RGETATTR st_result_mask=%lld\n"
1443 		"<<< qid=%x.%llx.%x\n"
1444 		"<<< st_mode=%8.8x st_nlink=%llu\n"
1445 		"<<< st_uid=%d st_gid=%d\n"
1446 		"<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1447 		"<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1448 		"<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1449 		"<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1450 		"<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1451 		"<<< st_gen=%lld st_data_version=%lld",
1452 		ret->st_result_mask, ret->qid.type, ret->qid.path,
1453 		ret->qid.version, ret->st_mode, ret->st_nlink, ret->st_uid,
1454 		ret->st_gid, ret->st_rdev, ret->st_size, ret->st_blksize,
1455 		ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1456 		ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1457 		ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1458 		ret->st_gen, ret->st_data_version);
1459 
1460 	p9_free_req(clnt, req);
1461 	return ret;
1462 
1463 error:
1464 	kfree(ret);
1465 	return ERR_PTR(err);
1466 }
1467 EXPORT_SYMBOL(p9_client_getattr_dotl);
1468 
1469 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1470 {
1471 	int ret;
1472 
1473 	/* NOTE: size shouldn't include its own length */
1474 	/* size[2] type[2] dev[4] qid[13] */
1475 	/* mode[4] atime[4] mtime[4] length[8]*/
1476 	/* name[s] uid[s] gid[s] muid[s] */
1477 	ret = 2+4+13+4+4+4+8+2+2+2+2;
1478 
1479 	if (wst->name)
1480 		ret += strlen(wst->name);
1481 	if (wst->uid)
1482 		ret += strlen(wst->uid);
1483 	if (wst->gid)
1484 		ret += strlen(wst->gid);
1485 	if (wst->muid)
1486 		ret += strlen(wst->muid);
1487 
1488 	if ((proto_version == p9_proto_2000u) ||
1489 		(proto_version == p9_proto_2000L)) {
1490 		ret += 2+4+4+4;	/* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1491 		if (wst->extension)
1492 			ret += strlen(wst->extension);
1493 	}
1494 
1495 	return ret;
1496 }
1497 
1498 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1499 {
1500 	int err;
1501 	struct p9_req_t *req;
1502 	struct p9_client *clnt;
1503 
1504 	err = 0;
1505 	clnt = fid->clnt;
1506 	wst->size = p9_client_statsize(wst, clnt->proto_version);
1507 	P9_DPRINTK(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1508 	P9_DPRINTK(P9_DEBUG_9P,
1509 		"     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1510 		"     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1511 		"     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1512 		"     uid=%d gid=%d n_muid=%d\n",
1513 		wst->size, wst->type, wst->dev, wst->qid.type,
1514 		(unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1515 		wst->atime, wst->mtime, (unsigned long long)wst->length,
1516 		wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1517 		wst->n_uid, wst->n_gid, wst->n_muid);
1518 
1519 	req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1520 	if (IS_ERR(req)) {
1521 		err = PTR_ERR(req);
1522 		goto error;
1523 	}
1524 
1525 	P9_DPRINTK(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1526 
1527 	p9_free_req(clnt, req);
1528 error:
1529 	return err;
1530 }
1531 EXPORT_SYMBOL(p9_client_wstat);
1532 
1533 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1534 {
1535 	int err;
1536 	struct p9_req_t *req;
1537 	struct p9_client *clnt;
1538 
1539 	err = 0;
1540 	clnt = fid->clnt;
1541 	P9_DPRINTK(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1542 	P9_DPRINTK(P9_DEBUG_9P,
1543 		"    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1544 		"    atime_sec=%lld atime_nsec=%lld\n"
1545 		"    mtime_sec=%lld mtime_nsec=%lld\n",
1546 		p9attr->valid, p9attr->mode, p9attr->uid, p9attr->gid,
1547 		p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1548 		p9attr->mtime_sec, p9attr->mtime_nsec);
1549 
1550 	req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1551 
1552 	if (IS_ERR(req)) {
1553 		err = PTR_ERR(req);
1554 		goto error;
1555 	}
1556 	P9_DPRINTK(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1557 	p9_free_req(clnt, req);
1558 error:
1559 	return err;
1560 }
1561 EXPORT_SYMBOL(p9_client_setattr);
1562 
1563 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1564 {
1565 	int err;
1566 	struct p9_req_t *req;
1567 	struct p9_client *clnt;
1568 
1569 	err = 0;
1570 	clnt = fid->clnt;
1571 
1572 	P9_DPRINTK(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1573 
1574 	req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1575 	if (IS_ERR(req)) {
1576 		err = PTR_ERR(req);
1577 		goto error;
1578 	}
1579 
1580 	err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1581 		&sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1582 		&sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1583 	if (err) {
1584 		p9pdu_dump(1, req->rc);
1585 		p9_free_req(clnt, req);
1586 		goto error;
1587 	}
1588 
1589 	P9_DPRINTK(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1590 		"blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1591 		"fsid %llu namelen %ld\n",
1592 		fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1593 		sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1594 		sb->fsid, (long int)sb->namelen);
1595 
1596 	p9_free_req(clnt, req);
1597 error:
1598 	return err;
1599 }
1600 EXPORT_SYMBOL(p9_client_statfs);
1601 
1602 int p9_client_rename(struct p9_fid *fid, struct p9_fid *newdirfid, char *name)
1603 {
1604 	int err;
1605 	struct p9_req_t *req;
1606 	struct p9_client *clnt;
1607 
1608 	err = 0;
1609 	clnt = fid->clnt;
1610 
1611 	P9_DPRINTK(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1612 			fid->fid, newdirfid->fid, name);
1613 
1614 	req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1615 			newdirfid->fid, name);
1616 	if (IS_ERR(req)) {
1617 		err = PTR_ERR(req);
1618 		goto error;
1619 	}
1620 
1621 	P9_DPRINTK(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1622 
1623 	p9_free_req(clnt, req);
1624 error:
1625 	return err;
1626 }
1627 EXPORT_SYMBOL(p9_client_rename);
1628 
1629 /*
1630  * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1631  */
1632 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1633 				const char *attr_name, u64 *attr_size)
1634 {
1635 	int err;
1636 	struct p9_req_t *req;
1637 	struct p9_client *clnt;
1638 	struct p9_fid *attr_fid;
1639 
1640 	err = 0;
1641 	clnt = file_fid->clnt;
1642 	attr_fid = p9_fid_create(clnt);
1643 	if (IS_ERR(attr_fid)) {
1644 		err = PTR_ERR(attr_fid);
1645 		attr_fid = NULL;
1646 		goto error;
1647 	}
1648 	P9_DPRINTK(P9_DEBUG_9P,
1649 		">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
1650 		file_fid->fid, attr_fid->fid, attr_name);
1651 
1652 	req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
1653 			file_fid->fid, attr_fid->fid, attr_name);
1654 	if (IS_ERR(req)) {
1655 		err = PTR_ERR(req);
1656 		goto error;
1657 	}
1658 	err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
1659 	if (err) {
1660 		p9pdu_dump(1, req->rc);
1661 		p9_free_req(clnt, req);
1662 		goto clunk_fid;
1663 	}
1664 	p9_free_req(clnt, req);
1665 	P9_DPRINTK(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
1666 		attr_fid->fid, *attr_size);
1667 	return attr_fid;
1668 clunk_fid:
1669 	p9_client_clunk(attr_fid);
1670 	attr_fid = NULL;
1671 error:
1672 	if (attr_fid && (attr_fid != file_fid))
1673 		p9_fid_destroy(attr_fid);
1674 
1675 	return ERR_PTR(err);
1676 }
1677 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
1678 
1679 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
1680 			u64 attr_size, int flags)
1681 {
1682 	int err;
1683 	struct p9_req_t *req;
1684 	struct p9_client *clnt;
1685 
1686 	P9_DPRINTK(P9_DEBUG_9P,
1687 		">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
1688 		fid->fid, name, (long long)attr_size, flags);
1689 	err = 0;
1690 	clnt = fid->clnt;
1691 	req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
1692 			fid->fid, name, attr_size, flags);
1693 	if (IS_ERR(req)) {
1694 		err = PTR_ERR(req);
1695 		goto error;
1696 	}
1697 	P9_DPRINTK(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
1698 	p9_free_req(clnt, req);
1699 error:
1700 	return err;
1701 }
1702 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
1703 
1704 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
1705 {
1706 	int err, rsize, total;
1707 	struct p9_client *clnt;
1708 	struct p9_req_t *req;
1709 	char *dataptr;
1710 
1711 	P9_DPRINTK(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
1712 				fid->fid, (long long unsigned) offset, count);
1713 
1714 	err = 0;
1715 	clnt = fid->clnt;
1716 	total = 0;
1717 
1718 	rsize = fid->iounit;
1719 	if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
1720 		rsize = clnt->msize - P9_READDIRHDRSZ;
1721 
1722 	if (count < rsize)
1723 		rsize = count;
1724 
1725 	req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid, offset, rsize);
1726 	if (IS_ERR(req)) {
1727 		err = PTR_ERR(req);
1728 		goto error;
1729 	}
1730 
1731 	err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1732 	if (err) {
1733 		p9pdu_dump(1, req->rc);
1734 		goto free_and_error;
1735 	}
1736 
1737 	P9_DPRINTK(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
1738 
1739 	if (data)
1740 		memmove(data, dataptr, count);
1741 
1742 	p9_free_req(clnt, req);
1743 	return count;
1744 
1745 free_and_error:
1746 	p9_free_req(clnt, req);
1747 error:
1748 	return err;
1749 }
1750 EXPORT_SYMBOL(p9_client_readdir);
1751 
1752 int p9_client_mknod_dotl(struct p9_fid *fid, char *name, int mode,
1753 			dev_t rdev, gid_t gid, struct p9_qid *qid)
1754 {
1755 	int err;
1756 	struct p9_client *clnt;
1757 	struct p9_req_t *req;
1758 
1759 	err = 0;
1760 	clnt = fid->clnt;
1761 	P9_DPRINTK(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
1762 		"minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
1763 	req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddd", fid->fid, name, mode,
1764 		MAJOR(rdev), MINOR(rdev), gid);
1765 	if (IS_ERR(req))
1766 		return PTR_ERR(req);
1767 
1768 	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1769 	if (err) {
1770 		p9pdu_dump(1, req->rc);
1771 		goto error;
1772 	}
1773 	P9_DPRINTK(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
1774 				(unsigned long long)qid->path, qid->version);
1775 
1776 error:
1777 	p9_free_req(clnt, req);
1778 	return err;
1779 
1780 }
1781 EXPORT_SYMBOL(p9_client_mknod_dotl);
1782 
1783 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
1784 				gid_t gid, struct p9_qid *qid)
1785 {
1786 	int err;
1787 	struct p9_client *clnt;
1788 	struct p9_req_t *req;
1789 
1790 	err = 0;
1791 	clnt = fid->clnt;
1792 	P9_DPRINTK(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
1793 		 fid->fid, name, mode, gid);
1794 	req = p9_client_rpc(clnt, P9_TMKDIR, "dsdd", fid->fid, name, mode,
1795 		gid);
1796 	if (IS_ERR(req))
1797 		return PTR_ERR(req);
1798 
1799 	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1800 	if (err) {
1801 		p9pdu_dump(1, req->rc);
1802 		goto error;
1803 	}
1804 	P9_DPRINTK(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
1805 				(unsigned long long)qid->path, qid->version);
1806 
1807 error:
1808 	p9_free_req(clnt, req);
1809 	return err;
1810 
1811 }
1812 EXPORT_SYMBOL(p9_client_mkdir_dotl);
1813