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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
27
28#include <linux/module.h>
29#include <linux/errno.h>
30#include <linux/fs.h>
31#include <linux/poll.h>
32#include <linux/idr.h>
33#include <linux/mutex.h>
34#include <linux/slab.h>
35#include <linux/sched.h>
36#include <linux/uaccess.h>
37#include <linux/uio.h>
38#include <net/9p/9p.h>
39#include <linux/parser.h>
40#include <net/9p/client.h>
41#include <net/9p/transport.h>
42#include "protocol.h"
43
44#define CREATE_TRACE_POINTS
45#include <trace/events/9p.h>
46
47/*
48  * Client Option Parsing (code inspired by NFS code)
49  *  - a little lazy - parse all client options
50  */
51
52enum {
53	Opt_msize,
54	Opt_trans,
55	Opt_legacy,
56	Opt_version,
57	Opt_err,
58};
59
60static const match_table_t tokens = {
61	{Opt_msize, "msize=%u"},
62	{Opt_legacy, "noextend"},
63	{Opt_trans, "trans=%s"},
64	{Opt_version, "version=%s"},
65	{Opt_err, NULL},
66};
67
68inline int p9_is_proto_dotl(struct p9_client *clnt)
69{
70	return clnt->proto_version == p9_proto_2000L;
71}
72EXPORT_SYMBOL(p9_is_proto_dotl);
73
74inline int p9_is_proto_dotu(struct p9_client *clnt)
75{
76	return clnt->proto_version == p9_proto_2000u;
77}
78EXPORT_SYMBOL(p9_is_proto_dotu);
79
80/*
81 * Some error codes are taken directly from the server replies,
82 * make sure they are valid.
83 */
84static int safe_errno(int err)
85{
86	if ((err > 0) || (err < -MAX_ERRNO)) {
87		p9_debug(P9_DEBUG_ERROR, "Invalid error code %d\n", err);
88		return -EPROTO;
89	}
90	return err;
91}
92
93
94/* Interpret mount option for protocol version */
95static int get_protocol_version(char *s)
96{
97	int version = -EINVAL;
98
99	if (!strcmp(s, "9p2000")) {
100		version = p9_proto_legacy;
101		p9_debug(P9_DEBUG_9P, "Protocol version: Legacy\n");
102	} else if (!strcmp(s, "9p2000.u")) {
103		version = p9_proto_2000u;
104		p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
105	} else if (!strcmp(s, "9p2000.L")) {
106		version = p9_proto_2000L;
107		p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.L\n");
108	} else
109		pr_info("Unknown protocol version %s\n", s);
110
111	return version;
112}
113
114/**
115 * parse_options - parse mount options into client structure
116 * @opts: options string passed from mount
117 * @clnt: existing v9fs client information
118 *
119 * Return 0 upon success, -ERRNO upon failure
120 */
121
122static int parse_opts(char *opts, struct p9_client *clnt)
123{
124	char *options, *tmp_options;
125	char *p;
126	substring_t args[MAX_OPT_ARGS];
127	int option;
128	char *s;
129	int ret = 0;
130
131	clnt->proto_version = p9_proto_2000L;
132	clnt->msize = 8192;
133
134	if (!opts)
135		return 0;
136
137	tmp_options = kstrdup(opts, GFP_KERNEL);
138	if (!tmp_options) {
139		p9_debug(P9_DEBUG_ERROR,
140			 "failed to allocate copy of option string\n");
141		return -ENOMEM;
142	}
143	options = tmp_options;
144
145	while ((p = strsep(&options, ",")) != NULL) {
146		int token, r;
147		if (!*p)
148			continue;
149		token = match_token(p, tokens, args);
150		switch (token) {
151		case Opt_msize:
152			r = match_int(&args[0], &option);
153			if (r < 0) {
154				p9_debug(P9_DEBUG_ERROR,
155					 "integer field, but no integer?\n");
156				ret = r;
157				continue;
158			}
159			clnt->msize = option;
160			break;
161		case Opt_trans:
162			s = match_strdup(&args[0]);
163			if (!s) {
164				ret = -ENOMEM;
165				p9_debug(P9_DEBUG_ERROR,
166					 "problem allocating copy of trans arg\n");
167				goto free_and_return;
168			 }
169			clnt->trans_mod = v9fs_get_trans_by_name(s);
170			if (clnt->trans_mod == NULL) {
171				pr_info("Could not find request transport: %s\n",
172					s);
173				ret = -EINVAL;
174				kfree(s);
175				goto free_and_return;
176			}
177			kfree(s);
178			break;
179		case Opt_legacy:
180			clnt->proto_version = p9_proto_legacy;
181			break;
182		case Opt_version:
183			s = match_strdup(&args[0]);
184			if (!s) {
185				ret = -ENOMEM;
186				p9_debug(P9_DEBUG_ERROR,
187					 "problem allocating copy of version arg\n");
188				goto free_and_return;
189			}
190			ret = get_protocol_version(s);
191			if (ret == -EINVAL) {
192				kfree(s);
193				goto free_and_return;
194			}
195			kfree(s);
196			clnt->proto_version = ret;
197			break;
198		default:
199			continue;
200		}
201	}
202
203free_and_return:
204	kfree(tmp_options);
205	return ret;
206}
207
208static struct p9_fcall *p9_fcall_alloc(int alloc_msize)
209{
210	struct p9_fcall *fc;
211	fc = kmalloc(sizeof(struct p9_fcall) + alloc_msize, GFP_NOFS);
212	if (!fc)
213		return NULL;
214	fc->capacity = alloc_msize;
215	fc->sdata = (char *) fc + sizeof(struct p9_fcall);
216	return fc;
217}
218
219/**
220 * p9_tag_alloc - lookup/allocate a request by tag
221 * @c: client session to lookup tag within
222 * @tag: numeric id for transaction
223 *
224 * this is a simple array lookup, but will grow the
225 * request_slots as necessary to accommodate transaction
226 * ids which did not previously have a slot.
227 *
228 * this code relies on the client spinlock to manage locks, its
229 * possible we should switch to something else, but I'd rather
230 * stick with something low-overhead for the common case.
231 *
232 */
233
234static struct p9_req_t *
235p9_tag_alloc(struct p9_client *c, u16 tag, unsigned int max_size)
236{
237	unsigned long flags;
238	int row, col;
239	struct p9_req_t *req;
240	int alloc_msize = min(c->msize, max_size);
241
242	/* This looks up the original request by tag so we know which
243	 * buffer to read the data into */
244	tag++;
245
246	if (tag >= c->max_tag) {
247		spin_lock_irqsave(&c->lock, flags);
248		/* check again since original check was outside of lock */
249		while (tag >= c->max_tag) {
250			row = (tag / P9_ROW_MAXTAG);
251			c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
252					sizeof(struct p9_req_t), GFP_ATOMIC);
253
254			if (!c->reqs[row]) {
255				pr_err("Couldn't grow tag array\n");
256				spin_unlock_irqrestore(&c->lock, flags);
257				return ERR_PTR(-ENOMEM);
258			}
259			for (col = 0; col < P9_ROW_MAXTAG; col++) {
260				c->reqs[row][col].status = REQ_STATUS_IDLE;
261				c->reqs[row][col].tc = NULL;
262			}
263			c->max_tag += P9_ROW_MAXTAG;
264		}
265		spin_unlock_irqrestore(&c->lock, flags);
266	}
267	row = tag / P9_ROW_MAXTAG;
268	col = tag % P9_ROW_MAXTAG;
269
270	req = &c->reqs[row][col];
271	if (!req->wq) {
272		req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_NOFS);
273		if (!req->wq)
274			goto grow_failed;
275		init_waitqueue_head(req->wq);
276	}
277
278	if (!req->tc)
279		req->tc = p9_fcall_alloc(alloc_msize);
280	if (!req->rc)
281		req->rc = p9_fcall_alloc(alloc_msize);
282	if (!req->tc || !req->rc)
283		goto grow_failed;
284
285	p9pdu_reset(req->tc);
286	p9pdu_reset(req->rc);
287
288	req->tc->tag = tag-1;
289	req->status = REQ_STATUS_ALLOC;
290
291	return req;
292
293grow_failed:
294	pr_err("Couldn't grow tag array\n");
295	kfree(req->tc);
296	kfree(req->rc);
297	kfree(req->wq);
298	req->tc = req->rc = NULL;
299	req->wq = NULL;
300	return ERR_PTR(-ENOMEM);
301}
302
303/**
304 * p9_tag_lookup - lookup a request by tag
305 * @c: client session to lookup tag within
306 * @tag: numeric id for transaction
307 *
308 */
309
310struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
311{
312	int row, col;
313
314	/* This looks up the original request by tag so we know which
315	 * buffer to read the data into */
316	tag++;
317
318	if(tag >= c->max_tag)
319		return NULL;
320
321	row = tag / P9_ROW_MAXTAG;
322	col = tag % P9_ROW_MAXTAG;
323
324	return &c->reqs[row][col];
325}
326EXPORT_SYMBOL(p9_tag_lookup);
327
328/**
329 * p9_tag_init - setup tags structure and contents
330 * @c:  v9fs client struct
331 *
332 * This initializes the tags structure for each client instance.
333 *
334 */
335
336static int p9_tag_init(struct p9_client *c)
337{
338	int err = 0;
339
340	c->tagpool = p9_idpool_create();
341	if (IS_ERR(c->tagpool)) {
342		err = PTR_ERR(c->tagpool);
343		goto error;
344	}
345	err = p9_idpool_get(c->tagpool); /* reserve tag 0 */
346	if (err < 0) {
347		p9_idpool_destroy(c->tagpool);
348		goto error;
349	}
350	c->max_tag = 0;
351error:
352	return err;
353}
354
355/**
356 * p9_tag_cleanup - cleans up tags structure and reclaims resources
357 * @c:  v9fs client struct
358 *
359 * This frees resources associated with the tags structure
360 *
361 */
362static void p9_tag_cleanup(struct p9_client *c)
363{
364	int row, col;
365
366	/* check to insure all requests are idle */
367	for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
368		for (col = 0; col < P9_ROW_MAXTAG; col++) {
369			if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
370				p9_debug(P9_DEBUG_MUX,
371					 "Attempting to cleanup non-free tag %d,%d\n",
372					 row, col);
373				/* TODO: delay execution of cleanup */
374				return;
375			}
376		}
377	}
378
379	if (c->tagpool) {
380		p9_idpool_put(0, c->tagpool); /* free reserved tag 0 */
381		p9_idpool_destroy(c->tagpool);
382	}
383
384	/* free requests associated with tags */
385	for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
386		for (col = 0; col < P9_ROW_MAXTAG; col++) {
387			kfree(c->reqs[row][col].wq);
388			kfree(c->reqs[row][col].tc);
389			kfree(c->reqs[row][col].rc);
390		}
391		kfree(c->reqs[row]);
392	}
393	c->max_tag = 0;
394}
395
396/**
397 * p9_free_req - free a request and clean-up as necessary
398 * c: client state
399 * r: request to release
400 *
401 */
402
403static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
404{
405	int tag = r->tc->tag;
406	p9_debug(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
407
408	r->status = REQ_STATUS_IDLE;
409	if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
410		p9_idpool_put(tag, c->tagpool);
411}
412
413/**
414 * p9_client_cb - call back from transport to client
415 * c: client state
416 * req: request received
417 *
418 */
419void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status)
420{
421	p9_debug(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
422
423	/*
424	 * This barrier is needed to make sure any change made to req before
425	 * the other thread wakes up will indeed be seen by the waiting side.
426	 */
427	smp_wmb();
428	req->status = status;
429
430	wake_up(req->wq);
431	p9_debug(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
432}
433EXPORT_SYMBOL(p9_client_cb);
434
435/**
436 * p9_parse_header - parse header arguments out of a packet
437 * @pdu: packet to parse
438 * @size: size of packet
439 * @type: type of request
440 * @tag: tag of packet
441 * @rewind: set if we need to rewind offset afterwards
442 */
443
444int
445p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
446								int rewind)
447{
448	int8_t r_type;
449	int16_t r_tag;
450	int32_t r_size;
451	int offset = pdu->offset;
452	int err;
453
454	pdu->offset = 0;
455	if (pdu->size == 0)
456		pdu->size = 7;
457
458	err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
459	if (err)
460		goto rewind_and_exit;
461
462	pdu->size = r_size;
463	pdu->id = r_type;
464	pdu->tag = r_tag;
465
466	p9_debug(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n",
467		 pdu->size, pdu->id, pdu->tag);
468
469	if (type)
470		*type = r_type;
471	if (tag)
472		*tag = r_tag;
473	if (size)
474		*size = r_size;
475
476
477rewind_and_exit:
478	if (rewind)
479		pdu->offset = offset;
480	return err;
481}
482EXPORT_SYMBOL(p9_parse_header);
483
484/**
485 * p9_check_errors - check 9p packet for error return and process it
486 * @c: current client instance
487 * @req: request to parse and check for error conditions
488 *
489 * returns error code if one is discovered, otherwise returns 0
490 *
491 * this will have to be more complicated if we have multiple
492 * error packet types
493 */
494
495static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
496{
497	int8_t type;
498	int err;
499	int ecode;
500
501	err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
502	/*
503	 * dump the response from server
504	 * This should be after check errors which poplulate pdu_fcall.
505	 */
506	trace_9p_protocol_dump(c, req->rc);
507	if (err) {
508		p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
509		return err;
510	}
511	if (type != P9_RERROR && type != P9_RLERROR)
512		return 0;
513
514	if (!p9_is_proto_dotl(c)) {
515		char *ename;
516		err = p9pdu_readf(req->rc, c->proto_version, "s?d",
517				  &ename, &ecode);
518		if (err)
519			goto out_err;
520
521		if (p9_is_proto_dotu(c))
522			err = -ecode;
523
524		if (!err || !IS_ERR_VALUE(err)) {
525			err = p9_errstr2errno(ename, strlen(ename));
526
527			p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
528				 -ecode, ename);
529		}
530		kfree(ename);
531	} else {
532		err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
533		err = -ecode;
534
535		p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
536	}
537
538	return err;
539
540out_err:
541	p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
542
543	return err;
544}
545
546/**
547 * p9_check_zc_errors - check 9p packet for error return and process it
548 * @c: current client instance
549 * @req: request to parse and check for error conditions
550 * @in_hdrlen: Size of response protocol buffer.
551 *
552 * returns error code if one is discovered, otherwise returns 0
553 *
554 * this will have to be more complicated if we have multiple
555 * error packet types
556 */
557
558static int p9_check_zc_errors(struct p9_client *c, struct p9_req_t *req,
559			      struct iov_iter *uidata, int in_hdrlen)
560{
561	int err;
562	int ecode;
563	int8_t type;
564	char *ename = NULL;
565
566	err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
567	/*
568	 * dump the response from server
569	 * This should be after parse_header which poplulate pdu_fcall.
570	 */
571	trace_9p_protocol_dump(c, req->rc);
572	if (err) {
573		p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
574		return err;
575	}
576
577	if (type != P9_RERROR && type != P9_RLERROR)
578		return 0;
579
580	if (!p9_is_proto_dotl(c)) {
581		/* Error is reported in string format */
582		int len;
583		/* 7 = header size for RERROR; */
584		int inline_len = in_hdrlen - 7;
585
586		len =  req->rc->size - req->rc->offset;
587		if (len > (P9_ZC_HDR_SZ - 7)) {
588			err = -EFAULT;
589			goto out_err;
590		}
591
592		ename = &req->rc->sdata[req->rc->offset];
593		if (len > inline_len) {
594			/* We have error in external buffer */
595			err = copy_from_iter(ename + inline_len,
596					     len - inline_len, uidata);
597			if (err != len - inline_len) {
598				err = -EFAULT;
599				goto out_err;
600			}
601		}
602		ename = NULL;
603		err = p9pdu_readf(req->rc, c->proto_version, "s?d",
604				  &ename, &ecode);
605		if (err)
606			goto out_err;
607
608		if (p9_is_proto_dotu(c))
609			err = -ecode;
610
611		if (!err || !IS_ERR_VALUE(err)) {
612			err = p9_errstr2errno(ename, strlen(ename));
613
614			p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
615				 -ecode, ename);
616		}
617		kfree(ename);
618	} else {
619		err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
620		err = -ecode;
621
622		p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
623	}
624	return err;
625
626out_err:
627	p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
628	return err;
629}
630
631static struct p9_req_t *
632p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
633
634/**
635 * p9_client_flush - flush (cancel) a request
636 * @c: client state
637 * @oldreq: request to cancel
638 *
639 * This sents a flush for a particular request and links
640 * the flush request to the original request.  The current
641 * code only supports a single flush request although the protocol
642 * allows for multiple flush requests to be sent for a single request.
643 *
644 */
645
646static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
647{
648	struct p9_req_t *req;
649	int16_t oldtag;
650	int err;
651
652	err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
653	if (err)
654		return err;
655
656	p9_debug(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
657
658	req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
659	if (IS_ERR(req))
660		return PTR_ERR(req);
661
662	/*
663	 * if we haven't received a response for oldreq,
664	 * remove it from the list
665	 */
666	if (oldreq->status == REQ_STATUS_SENT)
667		if (c->trans_mod->cancelled)
668			c->trans_mod->cancelled(c, oldreq);
669
670	p9_free_req(c, req);
671	return 0;
672}
673
674static struct p9_req_t *p9_client_prepare_req(struct p9_client *c,
675					      int8_t type, int req_size,
676					      const char *fmt, va_list ap)
677{
678	int tag, err;
679	struct p9_req_t *req;
680
681	p9_debug(P9_DEBUG_MUX, "client %p op %d\n", c, type);
682
683	/* we allow for any status other than disconnected */
684	if (c->status == Disconnected)
685		return ERR_PTR(-EIO);
686
687	/* if status is begin_disconnected we allow only clunk request */
688	if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
689		return ERR_PTR(-EIO);
690
691	tag = P9_NOTAG;
692	if (type != P9_TVERSION) {
693		tag = p9_idpool_get(c->tagpool);
694		if (tag < 0)
695			return ERR_PTR(-ENOMEM);
696	}
697
698	req = p9_tag_alloc(c, tag, req_size);
699	if (IS_ERR(req))
700		return req;
701
702	/* marshall the data */
703	p9pdu_prepare(req->tc, tag, type);
704	err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
705	if (err)
706		goto reterr;
707	p9pdu_finalize(c, req->tc);
708	trace_9p_client_req(c, type, tag);
709	return req;
710reterr:
711	p9_free_req(c, req);
712	return ERR_PTR(err);
713}
714
715/**
716 * p9_client_rpc - issue a request and wait for a response
717 * @c: client session
718 * @type: type of request
719 * @fmt: protocol format string (see protocol.c)
720 *
721 * Returns request structure (which client must free using p9_free_req)
722 */
723
724static struct p9_req_t *
725p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
726{
727	va_list ap;
728	int sigpending, err;
729	unsigned long flags;
730	struct p9_req_t *req;
731
732	va_start(ap, fmt);
733	req = p9_client_prepare_req(c, type, c->msize, fmt, ap);
734	va_end(ap);
735	if (IS_ERR(req))
736		return req;
737
738	if (signal_pending(current)) {
739		sigpending = 1;
740		clear_thread_flag(TIF_SIGPENDING);
741	} else
742		sigpending = 0;
743
744	err = c->trans_mod->request(c, req);
745	if (err < 0) {
746		if (err != -ERESTARTSYS && err != -EFAULT)
747			c->status = Disconnected;
748		goto reterr;
749	}
750again:
751	/* Wait for the response */
752	err = wait_event_interruptible(*req->wq,
753				       req->status >= REQ_STATUS_RCVD);
754
755	/*
756	 * Make sure our req is coherent with regard to updates in other
757	 * threads - echoes to wmb() in the callback
758	 */
759	smp_rmb();
760
761	if ((err == -ERESTARTSYS) && (c->status == Connected)
762				  && (type == P9_TFLUSH)) {
763		sigpending = 1;
764		clear_thread_flag(TIF_SIGPENDING);
765		goto again;
766	}
767
768	if (req->status == REQ_STATUS_ERROR) {
769		p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
770		err = req->t_err;
771	}
772	if ((err == -ERESTARTSYS) && (c->status == Connected)) {
773		p9_debug(P9_DEBUG_MUX, "flushing\n");
774		sigpending = 1;
775		clear_thread_flag(TIF_SIGPENDING);
776
777		if (c->trans_mod->cancel(c, req))
778			p9_client_flush(c, req);
779
780		/* if we received the response anyway, don't signal error */
781		if (req->status == REQ_STATUS_RCVD)
782			err = 0;
783	}
784	if (sigpending) {
785		spin_lock_irqsave(&current->sighand->siglock, flags);
786		recalc_sigpending();
787		spin_unlock_irqrestore(&current->sighand->siglock, flags);
788	}
789	if (err < 0)
790		goto reterr;
791
792	err = p9_check_errors(c, req);
793	trace_9p_client_res(c, type, req->rc->tag, err);
794	if (!err)
795		return req;
796reterr:
797	p9_free_req(c, req);
798	return ERR_PTR(safe_errno(err));
799}
800
801/**
802 * p9_client_zc_rpc - issue a request and wait for a response
803 * @c: client session
804 * @type: type of request
805 * @uidata: destination for zero copy read
806 * @uodata: source for zero copy write
807 * @inlen: read buffer size
808 * @olen: write buffer size
809 * @hdrlen: reader header size, This is the size of response protocol data
810 * @fmt: protocol format string (see protocol.c)
811 *
812 * Returns request structure (which client must free using p9_free_req)
813 */
814static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
815					 struct iov_iter *uidata,
816					 struct iov_iter *uodata,
817					 int inlen, int olen, int in_hdrlen,
818					 const char *fmt, ...)
819{
820	va_list ap;
821	int sigpending, err;
822	unsigned long flags;
823	struct p9_req_t *req;
824
825	va_start(ap, fmt);
826	/*
827	 * We allocate a inline protocol data of only 4k bytes.
828	 * The actual content is passed in zero-copy fashion.
829	 */
830	req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, fmt, ap);
831	va_end(ap);
832	if (IS_ERR(req))
833		return req;
834
835	if (signal_pending(current)) {
836		sigpending = 1;
837		clear_thread_flag(TIF_SIGPENDING);
838	} else
839		sigpending = 0;
840
841	err = c->trans_mod->zc_request(c, req, uidata, uodata,
842				       inlen, olen, in_hdrlen);
843	if (err < 0) {
844		if (err == -EIO)
845			c->status = Disconnected;
846		if (err != -ERESTARTSYS)
847			goto reterr;
848	}
849	if (req->status == REQ_STATUS_ERROR) {
850		p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
851		err = req->t_err;
852	}
853	if ((err == -ERESTARTSYS) && (c->status == Connected)) {
854		p9_debug(P9_DEBUG_MUX, "flushing\n");
855		sigpending = 1;
856		clear_thread_flag(TIF_SIGPENDING);
857
858		if (c->trans_mod->cancel(c, req))
859			p9_client_flush(c, req);
860
861		/* if we received the response anyway, don't signal error */
862		if (req->status == REQ_STATUS_RCVD)
863			err = 0;
864	}
865	if (sigpending) {
866		spin_lock_irqsave(&current->sighand->siglock, flags);
867		recalc_sigpending();
868		spin_unlock_irqrestore(&current->sighand->siglock, flags);
869	}
870	if (err < 0)
871		goto reterr;
872
873	err = p9_check_zc_errors(c, req, uidata, in_hdrlen);
874	trace_9p_client_res(c, type, req->rc->tag, err);
875	if (!err)
876		return req;
877reterr:
878	p9_free_req(c, req);
879	return ERR_PTR(safe_errno(err));
880}
881
882static struct p9_fid *p9_fid_create(struct p9_client *clnt)
883{
884	int ret;
885	struct p9_fid *fid;
886	unsigned long flags;
887
888	p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt);
889	fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
890	if (!fid)
891		return ERR_PTR(-ENOMEM);
892
893	ret = p9_idpool_get(clnt->fidpool);
894	if (ret < 0) {
895		ret = -ENOSPC;
896		goto error;
897	}
898	fid->fid = ret;
899
900	memset(&fid->qid, 0, sizeof(struct p9_qid));
901	fid->mode = -1;
902	fid->uid = current_fsuid();
903	fid->clnt = clnt;
904	fid->rdir = NULL;
905	spin_lock_irqsave(&clnt->lock, flags);
906	list_add(&fid->flist, &clnt->fidlist);
907	spin_unlock_irqrestore(&clnt->lock, flags);
908
909	return fid;
910
911error:
912	kfree(fid);
913	return ERR_PTR(ret);
914}
915
916static void p9_fid_destroy(struct p9_fid *fid)
917{
918	struct p9_client *clnt;
919	unsigned long flags;
920
921	p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
922	clnt = fid->clnt;
923	p9_idpool_put(fid->fid, clnt->fidpool);
924	spin_lock_irqsave(&clnt->lock, flags);
925	list_del(&fid->flist);
926	spin_unlock_irqrestore(&clnt->lock, flags);
927	kfree(fid->rdir);
928	kfree(fid);
929}
930
931static int p9_client_version(struct p9_client *c)
932{
933	int err = 0;
934	struct p9_req_t *req;
935	char *version;
936	int msize;
937
938	p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
939		 c->msize, c->proto_version);
940
941	switch (c->proto_version) {
942	case p9_proto_2000L:
943		req = p9_client_rpc(c, P9_TVERSION, "ds",
944					c->msize, "9P2000.L");
945		break;
946	case p9_proto_2000u:
947		req = p9_client_rpc(c, P9_TVERSION, "ds",
948					c->msize, "9P2000.u");
949		break;
950	case p9_proto_legacy:
951		req = p9_client_rpc(c, P9_TVERSION, "ds",
952					c->msize, "9P2000");
953		break;
954	default:
955		return -EINVAL;
956	}
957
958	if (IS_ERR(req))
959		return PTR_ERR(req);
960
961	err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
962	if (err) {
963		p9_debug(P9_DEBUG_9P, "version error %d\n", err);
964		trace_9p_protocol_dump(c, req->rc);
965		goto error;
966	}
967
968	p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
969	if (!strncmp(version, "9P2000.L", 8))
970		c->proto_version = p9_proto_2000L;
971	else if (!strncmp(version, "9P2000.u", 8))
972		c->proto_version = p9_proto_2000u;
973	else if (!strncmp(version, "9P2000", 6))
974		c->proto_version = p9_proto_legacy;
975	else {
976		err = -EREMOTEIO;
977		goto error;
978	}
979
980	if (msize < c->msize)
981		c->msize = msize;
982
983error:
984	kfree(version);
985	p9_free_req(c, req);
986
987	return err;
988}
989
990struct p9_client *p9_client_create(const char *dev_name, char *options)
991{
992	int err;
993	struct p9_client *clnt;
994	char *client_id;
995
996	err = 0;
997	clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
998	if (!clnt)
999		return ERR_PTR(-ENOMEM);
1000
1001	clnt->trans_mod = NULL;
1002	clnt->trans = NULL;
1003
1004	client_id = utsname()->nodename;
1005	memcpy(clnt->name, client_id, strlen(client_id) + 1);
1006
1007	spin_lock_init(&clnt->lock);
1008	INIT_LIST_HEAD(&clnt->fidlist);
1009
1010	err = p9_tag_init(clnt);
1011	if (err < 0)
1012		goto free_client;
1013
1014	err = parse_opts(options, clnt);
1015	if (err < 0)
1016		goto destroy_tagpool;
1017
1018	if (!clnt->trans_mod)
1019		clnt->trans_mod = v9fs_get_default_trans();
1020
1021	if (clnt->trans_mod == NULL) {
1022		err = -EPROTONOSUPPORT;
1023		p9_debug(P9_DEBUG_ERROR,
1024			 "No transport defined or default transport\n");
1025		goto destroy_tagpool;
1026	}
1027
1028	clnt->fidpool = p9_idpool_create();
1029	if (IS_ERR(clnt->fidpool)) {
1030		err = PTR_ERR(clnt->fidpool);
1031		goto put_trans;
1032	}
1033
1034	p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1035		 clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1036
1037	err = clnt->trans_mod->create(clnt, dev_name, options);
1038	if (err)
1039		goto destroy_fidpool;
1040
1041	if (clnt->msize > clnt->trans_mod->maxsize)
1042		clnt->msize = clnt->trans_mod->maxsize;
1043
1044	err = p9_client_version(clnt);
1045	if (err)
1046		goto close_trans;
1047
1048	return clnt;
1049
1050close_trans:
1051	clnt->trans_mod->close(clnt);
1052destroy_fidpool:
1053	p9_idpool_destroy(clnt->fidpool);
1054put_trans:
1055	v9fs_put_trans(clnt->trans_mod);
1056destroy_tagpool:
1057	p9_idpool_destroy(clnt->tagpool);
1058free_client:
1059	kfree(clnt);
1060	return ERR_PTR(err);
1061}
1062EXPORT_SYMBOL(p9_client_create);
1063
1064void p9_client_destroy(struct p9_client *clnt)
1065{
1066	struct p9_fid *fid, *fidptr;
1067
1068	p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
1069
1070	if (clnt->trans_mod)
1071		clnt->trans_mod->close(clnt);
1072
1073	v9fs_put_trans(clnt->trans_mod);
1074
1075	list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
1076		pr_info("Found fid %d not clunked\n", fid->fid);
1077		p9_fid_destroy(fid);
1078	}
1079
1080	if (clnt->fidpool)
1081		p9_idpool_destroy(clnt->fidpool);
1082
1083	p9_tag_cleanup(clnt);
1084
1085	kfree(clnt);
1086}
1087EXPORT_SYMBOL(p9_client_destroy);
1088
1089void p9_client_disconnect(struct p9_client *clnt)
1090{
1091	p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1092	clnt->status = Disconnected;
1093}
1094EXPORT_SYMBOL(p9_client_disconnect);
1095
1096void p9_client_begin_disconnect(struct p9_client *clnt)
1097{
1098	p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1099	clnt->status = BeginDisconnect;
1100}
1101EXPORT_SYMBOL(p9_client_begin_disconnect);
1102
1103struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1104	char *uname, kuid_t n_uname, char *aname)
1105{
1106	int err = 0;
1107	struct p9_req_t *req;
1108	struct p9_fid *fid;
1109	struct p9_qid qid;
1110
1111
1112	p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1113		 afid ? afid->fid : -1, uname, aname);
1114	fid = p9_fid_create(clnt);
1115	if (IS_ERR(fid)) {
1116		err = PTR_ERR(fid);
1117		fid = NULL;
1118		goto error;
1119	}
1120	fid->uid = n_uname;
1121
1122	req = p9_client_rpc(clnt, P9_TATTACH, "ddss?u", fid->fid,
1123			afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1124	if (IS_ERR(req)) {
1125		err = PTR_ERR(req);
1126		goto error;
1127	}
1128
1129	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
1130	if (err) {
1131		trace_9p_protocol_dump(clnt, req->rc);
1132		p9_free_req(clnt, req);
1133		goto error;
1134	}
1135
1136	p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1137		 qid.type, (unsigned long long)qid.path, qid.version);
1138
1139	memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1140
1141	p9_free_req(clnt, req);
1142	return fid;
1143
1144error:
1145	if (fid)
1146		p9_fid_destroy(fid);
1147	return ERR_PTR(err);
1148}
1149EXPORT_SYMBOL(p9_client_attach);
1150
1151struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1152		char **wnames, int clone)
1153{
1154	int err;
1155	struct p9_client *clnt;
1156	struct p9_fid *fid;
1157	struct p9_qid *wqids;
1158	struct p9_req_t *req;
1159	uint16_t nwqids, count;
1160
1161	err = 0;
1162	wqids = NULL;
1163	clnt = oldfid->clnt;
1164	if (clone) {
1165		fid = p9_fid_create(clnt);
1166		if (IS_ERR(fid)) {
1167			err = PTR_ERR(fid);
1168			fid = NULL;
1169			goto error;
1170		}
1171
1172		fid->uid = oldfid->uid;
1173	} else
1174		fid = oldfid;
1175
1176
1177	p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1178		 oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1179
1180	req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1181								nwname, wnames);
1182	if (IS_ERR(req)) {
1183		err = PTR_ERR(req);
1184		goto error;
1185	}
1186
1187	err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1188	if (err) {
1189		trace_9p_protocol_dump(clnt, req->rc);
1190		p9_free_req(clnt, req);
1191		goto clunk_fid;
1192	}
1193	p9_free_req(clnt, req);
1194
1195	p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1196
1197	if (nwqids != nwname) {
1198		err = -ENOENT;
1199		goto clunk_fid;
1200	}
1201
1202	for (count = 0; count < nwqids; count++)
1203		p9_debug(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
1204			count, wqids[count].type,
1205			(unsigned long long)wqids[count].path,
1206			wqids[count].version);
1207
1208	if (nwname)
1209		memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1210	else
1211		fid->qid = oldfid->qid;
1212
1213	kfree(wqids);
1214	return fid;
1215
1216clunk_fid:
1217	kfree(wqids);
1218	p9_client_clunk(fid);
1219	fid = NULL;
1220
1221error:
1222	if (fid && (fid != oldfid))
1223		p9_fid_destroy(fid);
1224
1225	return ERR_PTR(err);
1226}
1227EXPORT_SYMBOL(p9_client_walk);
1228
1229int p9_client_open(struct p9_fid *fid, int mode)
1230{
1231	int err;
1232	struct p9_client *clnt;
1233	struct p9_req_t *req;
1234	struct p9_qid qid;
1235	int iounit;
1236
1237	clnt = fid->clnt;
1238	p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1239		p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1240	err = 0;
1241
1242	if (fid->mode != -1)
1243		return -EINVAL;
1244
1245	if (p9_is_proto_dotl(clnt))
1246		req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1247	else
1248		req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1249	if (IS_ERR(req)) {
1250		err = PTR_ERR(req);
1251		goto error;
1252	}
1253
1254	err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1255	if (err) {
1256		trace_9p_protocol_dump(clnt, req->rc);
1257		goto free_and_error;
1258	}
1259
1260	p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1261		p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1262		(unsigned long long)qid.path, qid.version, iounit);
1263
1264	fid->mode = mode;
1265	fid->iounit = iounit;
1266
1267free_and_error:
1268	p9_free_req(clnt, req);
1269error:
1270	return err;
1271}
1272EXPORT_SYMBOL(p9_client_open);
1273
1274int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
1275		kgid_t gid, struct p9_qid *qid)
1276{
1277	int err = 0;
1278	struct p9_client *clnt;
1279	struct p9_req_t *req;
1280	int iounit;
1281
1282	p9_debug(P9_DEBUG_9P,
1283			">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1284			ofid->fid, name, flags, mode,
1285		 	from_kgid(&init_user_ns, gid));
1286	clnt = ofid->clnt;
1287
1288	if (ofid->mode != -1)
1289		return -EINVAL;
1290
1291	req = p9_client_rpc(clnt, P9_TLCREATE, "dsddg", ofid->fid, name, flags,
1292			mode, gid);
1293	if (IS_ERR(req)) {
1294		err = PTR_ERR(req);
1295		goto error;
1296	}
1297
1298	err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1299	if (err) {
1300		trace_9p_protocol_dump(clnt, req->rc);
1301		goto free_and_error;
1302	}
1303
1304	p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1305			qid->type,
1306			(unsigned long long)qid->path,
1307			qid->version, iounit);
1308
1309	ofid->mode = mode;
1310	ofid->iounit = iounit;
1311
1312free_and_error:
1313	p9_free_req(clnt, req);
1314error:
1315	return err;
1316}
1317EXPORT_SYMBOL(p9_client_create_dotl);
1318
1319int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1320		     char *extension)
1321{
1322	int err;
1323	struct p9_client *clnt;
1324	struct p9_req_t *req;
1325	struct p9_qid qid;
1326	int iounit;
1327
1328	p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1329						fid->fid, name, perm, mode);
1330	err = 0;
1331	clnt = fid->clnt;
1332
1333	if (fid->mode != -1)
1334		return -EINVAL;
1335
1336	req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1337				mode, extension);
1338	if (IS_ERR(req)) {
1339		err = PTR_ERR(req);
1340		goto error;
1341	}
1342
1343	err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1344	if (err) {
1345		trace_9p_protocol_dump(clnt, req->rc);
1346		goto free_and_error;
1347	}
1348
1349	p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1350				qid.type,
1351				(unsigned long long)qid.path,
1352				qid.version, iounit);
1353
1354	fid->mode = mode;
1355	fid->iounit = iounit;
1356
1357free_and_error:
1358	p9_free_req(clnt, req);
1359error:
1360	return err;
1361}
1362EXPORT_SYMBOL(p9_client_fcreate);
1363
1364int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, kgid_t gid,
1365		struct p9_qid *qid)
1366{
1367	int err = 0;
1368	struct p9_client *clnt;
1369	struct p9_req_t *req;
1370
1371	p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1372			dfid->fid, name, symtgt);
1373	clnt = dfid->clnt;
1374
1375	req = p9_client_rpc(clnt, P9_TSYMLINK, "dssg", dfid->fid, name, symtgt,
1376			gid);
1377	if (IS_ERR(req)) {
1378		err = PTR_ERR(req);
1379		goto error;
1380	}
1381
1382	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1383	if (err) {
1384		trace_9p_protocol_dump(clnt, req->rc);
1385		goto free_and_error;
1386	}
1387
1388	p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1389			qid->type, (unsigned long long)qid->path, qid->version);
1390
1391free_and_error:
1392	p9_free_req(clnt, req);
1393error:
1394	return err;
1395}
1396EXPORT_SYMBOL(p9_client_symlink);
1397
1398int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
1399{
1400	struct p9_client *clnt;
1401	struct p9_req_t *req;
1402
1403	p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1404			dfid->fid, oldfid->fid, newname);
1405	clnt = dfid->clnt;
1406	req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1407			newname);
1408	if (IS_ERR(req))
1409		return PTR_ERR(req);
1410
1411	p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
1412	p9_free_req(clnt, req);
1413	return 0;
1414}
1415EXPORT_SYMBOL(p9_client_link);
1416
1417int p9_client_fsync(struct p9_fid *fid, int datasync)
1418{
1419	int err;
1420	struct p9_client *clnt;
1421	struct p9_req_t *req;
1422
1423	p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1424			fid->fid, datasync);
1425	err = 0;
1426	clnt = fid->clnt;
1427
1428	req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1429	if (IS_ERR(req)) {
1430		err = PTR_ERR(req);
1431		goto error;
1432	}
1433
1434	p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1435
1436	p9_free_req(clnt, req);
1437
1438error:
1439	return err;
1440}
1441EXPORT_SYMBOL(p9_client_fsync);
1442
1443int p9_client_clunk(struct p9_fid *fid)
1444{
1445	int err;
1446	struct p9_client *clnt;
1447	struct p9_req_t *req;
1448	int retries = 0;
1449
1450	if (!fid) {
1451		pr_warn("%s (%d): Trying to clunk with NULL fid\n",
1452			__func__, task_pid_nr(current));
1453		dump_stack();
1454		return 0;
1455	}
1456
1457again:
1458	p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n", fid->fid,
1459								retries);
1460	err = 0;
1461	clnt = fid->clnt;
1462
1463	req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1464	if (IS_ERR(req)) {
1465		err = PTR_ERR(req);
1466		goto error;
1467	}
1468
1469	p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1470
1471	p9_free_req(clnt, req);
1472error:
1473	/*
1474	 * Fid is not valid even after a failed clunk
1475	 * If interrupted, retry once then give up and
1476	 * leak fid until umount.
1477	 */
1478	if (err == -ERESTARTSYS) {
1479		if (retries++ == 0)
1480			goto again;
1481	} else
1482		p9_fid_destroy(fid);
1483	return err;
1484}
1485EXPORT_SYMBOL(p9_client_clunk);
1486
1487int p9_client_remove(struct p9_fid *fid)
1488{
1489	int err;
1490	struct p9_client *clnt;
1491	struct p9_req_t *req;
1492
1493	p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1494	err = 0;
1495	clnt = fid->clnt;
1496
1497	req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1498	if (IS_ERR(req)) {
1499		err = PTR_ERR(req);
1500		goto error;
1501	}
1502
1503	p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1504
1505	p9_free_req(clnt, req);
1506error:
1507	if (err == -ERESTARTSYS)
1508		p9_client_clunk(fid);
1509	else
1510		p9_fid_destroy(fid);
1511	return err;
1512}
1513EXPORT_SYMBOL(p9_client_remove);
1514
1515int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1516{
1517	int err = 0;
1518	struct p9_req_t *req;
1519	struct p9_client *clnt;
1520
1521	p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1522		   dfid->fid, name, flags);
1523
1524	clnt = dfid->clnt;
1525	req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1526	if (IS_ERR(req)) {
1527		err = PTR_ERR(req);
1528		goto error;
1529	}
1530	p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1531
1532	p9_free_req(clnt, req);
1533error:
1534	return err;
1535}
1536EXPORT_SYMBOL(p9_client_unlinkat);
1537
1538int
1539p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err)
1540{
1541	struct p9_client *clnt = fid->clnt;
1542	struct p9_req_t *req;
1543	int total = 0;
1544	*err = 0;
1545
1546	p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
1547		   fid->fid, (unsigned long long) offset, (int)iov_iter_count(to));
1548
1549	while (iov_iter_count(to)) {
1550		int count = iov_iter_count(to);
1551		int rsize, non_zc = 0;
1552		char *dataptr;
1553
1554		rsize = fid->iounit;
1555		if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1556			rsize = clnt->msize - P9_IOHDRSZ;
1557
1558		if (count < rsize)
1559			rsize = count;
1560
1561		/* Don't bother zerocopy for small IO (< 1024) */
1562		if (clnt->trans_mod->zc_request && rsize > 1024) {
1563			/*
1564			 * response header len is 11
1565			 * PDU Header(7) + IO Size (4)
1566			 */
1567			req = p9_client_zc_rpc(clnt, P9_TREAD, to, NULL, rsize,
1568					       0, 11, "dqd", fid->fid,
1569					       offset, rsize);
1570		} else {
1571			non_zc = 1;
1572			req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1573					    rsize);
1574		}
1575		if (IS_ERR(req)) {
1576			*err = PTR_ERR(req);
1577			break;
1578		}
1579
1580		*err = p9pdu_readf(req->rc, clnt->proto_version,
1581				   "D", &count, &dataptr);
1582		if (*err) {
1583			trace_9p_protocol_dump(clnt, req->rc);
1584			p9_free_req(clnt, req);
1585			break;
1586		}
1587
1588		p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1589		if (!count) {
1590			p9_free_req(clnt, req);
1591			break;
1592		}
1593
1594		if (non_zc) {
1595			int n = copy_to_iter(dataptr, count, to);
1596			total += n;
1597			offset += n;
1598			if (n != count) {
1599				*err = -EFAULT;
1600				p9_free_req(clnt, req);
1601				break;
1602			}
1603		} else {
1604			iov_iter_advance(to, count);
1605			total += count;
1606			offset += count;
1607		}
1608		p9_free_req(clnt, req);
1609	}
1610	return total;
1611}
1612EXPORT_SYMBOL(p9_client_read);
1613
1614int
1615p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err)
1616{
1617	struct p9_client *clnt = fid->clnt;
1618	struct p9_req_t *req;
1619	int total = 0;
1620	*err = 0;
1621
1622	p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %zd\n",
1623				fid->fid, (unsigned long long) offset,
1624				iov_iter_count(from));
1625
1626	while (iov_iter_count(from)) {
1627		int count = iov_iter_count(from);
1628		int rsize = fid->iounit;
1629		if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1630			rsize = clnt->msize - P9_IOHDRSZ;
1631
1632		if (count < rsize)
1633			rsize = count;
1634
1635		/* Don't bother zerocopy for small IO (< 1024) */
1636		if (clnt->trans_mod->zc_request && rsize > 1024) {
1637			req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, from, 0,
1638					       rsize, P9_ZC_HDR_SZ, "dqd",
1639					       fid->fid, offset, rsize);
1640		} else {
1641			req = p9_client_rpc(clnt, P9_TWRITE, "dqV", fid->fid,
1642						    offset, rsize, from);
1643		}
1644		if (IS_ERR(req)) {
1645			*err = PTR_ERR(req);
1646			break;
1647		}
1648
1649		*err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1650		if (*err) {
1651			trace_9p_protocol_dump(clnt, req->rc);
1652			p9_free_req(clnt, req);
1653			break;
1654		}
1655
1656		p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1657
1658		p9_free_req(clnt, req);
1659		iov_iter_advance(from, count);
1660		total += count;
1661		offset += count;
1662	}
1663	return total;
1664}
1665EXPORT_SYMBOL(p9_client_write);
1666
1667struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1668{
1669	int err;
1670	struct p9_client *clnt;
1671	struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1672	struct p9_req_t *req;
1673	u16 ignored;
1674
1675	p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1676
1677	if (!ret)
1678		return ERR_PTR(-ENOMEM);
1679
1680	err = 0;
1681	clnt = fid->clnt;
1682
1683	req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1684	if (IS_ERR(req)) {
1685		err = PTR_ERR(req);
1686		goto error;
1687	}
1688
1689	err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1690	if (err) {
1691		trace_9p_protocol_dump(clnt, req->rc);
1692		p9_free_req(clnt, req);
1693		goto error;
1694	}
1695
1696	p9_debug(P9_DEBUG_9P,
1697		"<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1698		"<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1699		"<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1700		"<<<    uid=%d gid=%d n_muid=%d\n",
1701		ret->size, ret->type, ret->dev, ret->qid.type,
1702		(unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1703		ret->atime, ret->mtime, (unsigned long long)ret->length,
1704		ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1705		from_kuid(&init_user_ns, ret->n_uid),
1706		from_kgid(&init_user_ns, ret->n_gid),
1707		from_kuid(&init_user_ns, ret->n_muid));
1708
1709	p9_free_req(clnt, req);
1710	return ret;
1711
1712error:
1713	kfree(ret);
1714	return ERR_PTR(err);
1715}
1716EXPORT_SYMBOL(p9_client_stat);
1717
1718struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1719							u64 request_mask)
1720{
1721	int err;
1722	struct p9_client *clnt;
1723	struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1724								GFP_KERNEL);
1725	struct p9_req_t *req;
1726
1727	p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1728							fid->fid, request_mask);
1729
1730	if (!ret)
1731		return ERR_PTR(-ENOMEM);
1732
1733	err = 0;
1734	clnt = fid->clnt;
1735
1736	req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1737	if (IS_ERR(req)) {
1738		err = PTR_ERR(req);
1739		goto error;
1740	}
1741
1742	err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1743	if (err) {
1744		trace_9p_protocol_dump(clnt, req->rc);
1745		p9_free_req(clnt, req);
1746		goto error;
1747	}
1748
1749	p9_debug(P9_DEBUG_9P,
1750		"<<< RGETATTR st_result_mask=%lld\n"
1751		"<<< qid=%x.%llx.%x\n"
1752		"<<< st_mode=%8.8x st_nlink=%llu\n"
1753		"<<< st_uid=%d st_gid=%d\n"
1754		"<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1755		"<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1756		"<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1757		"<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1758		"<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1759		"<<< st_gen=%lld st_data_version=%lld",
1760		ret->st_result_mask, ret->qid.type, ret->qid.path,
1761		ret->qid.version, ret->st_mode, ret->st_nlink,
1762		from_kuid(&init_user_ns, ret->st_uid),
1763		from_kgid(&init_user_ns, ret->st_gid),
1764		ret->st_rdev, ret->st_size, ret->st_blksize,
1765		ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1766		ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1767		ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1768		ret->st_gen, ret->st_data_version);
1769
1770	p9_free_req(clnt, req);
1771	return ret;
1772
1773error:
1774	kfree(ret);
1775	return ERR_PTR(err);
1776}
1777EXPORT_SYMBOL(p9_client_getattr_dotl);
1778
1779static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1780{
1781	int ret;
1782
1783	/* NOTE: size shouldn't include its own length */
1784	/* size[2] type[2] dev[4] qid[13] */
1785	/* mode[4] atime[4] mtime[4] length[8]*/
1786	/* name[s] uid[s] gid[s] muid[s] */
1787	ret = 2+4+13+4+4+4+8+2+2+2+2;
1788
1789	if (wst->name)
1790		ret += strlen(wst->name);
1791	if (wst->uid)
1792		ret += strlen(wst->uid);
1793	if (wst->gid)
1794		ret += strlen(wst->gid);
1795	if (wst->muid)
1796		ret += strlen(wst->muid);
1797
1798	if ((proto_version == p9_proto_2000u) ||
1799		(proto_version == p9_proto_2000L)) {
1800		ret += 2+4+4+4;	/* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1801		if (wst->extension)
1802			ret += strlen(wst->extension);
1803	}
1804
1805	return ret;
1806}
1807
1808int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1809{
1810	int err;
1811	struct p9_req_t *req;
1812	struct p9_client *clnt;
1813
1814	err = 0;
1815	clnt = fid->clnt;
1816	wst->size = p9_client_statsize(wst, clnt->proto_version);
1817	p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1818	p9_debug(P9_DEBUG_9P,
1819		"     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1820		"     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1821		"     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1822		"     uid=%d gid=%d n_muid=%d\n",
1823		wst->size, wst->type, wst->dev, wst->qid.type,
1824		(unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1825		wst->atime, wst->mtime, (unsigned long long)wst->length,
1826		wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1827		from_kuid(&init_user_ns, wst->n_uid),
1828		from_kgid(&init_user_ns, wst->n_gid),
1829		from_kuid(&init_user_ns, wst->n_muid));
1830
1831	req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1832	if (IS_ERR(req)) {
1833		err = PTR_ERR(req);
1834		goto error;
1835	}
1836
1837	p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1838
1839	p9_free_req(clnt, req);
1840error:
1841	return err;
1842}
1843EXPORT_SYMBOL(p9_client_wstat);
1844
1845int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1846{
1847	int err;
1848	struct p9_req_t *req;
1849	struct p9_client *clnt;
1850
1851	err = 0;
1852	clnt = fid->clnt;
1853	p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1854	p9_debug(P9_DEBUG_9P,
1855		"    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1856		"    atime_sec=%lld atime_nsec=%lld\n"
1857		"    mtime_sec=%lld mtime_nsec=%lld\n",
1858		p9attr->valid, p9attr->mode,
1859		from_kuid(&init_user_ns, p9attr->uid),
1860		from_kgid(&init_user_ns, p9attr->gid),
1861		p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1862		p9attr->mtime_sec, p9attr->mtime_nsec);
1863
1864	req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1865
1866	if (IS_ERR(req)) {
1867		err = PTR_ERR(req);
1868		goto error;
1869	}
1870	p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1871	p9_free_req(clnt, req);
1872error:
1873	return err;
1874}
1875EXPORT_SYMBOL(p9_client_setattr);
1876
1877int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1878{
1879	int err;
1880	struct p9_req_t *req;
1881	struct p9_client *clnt;
1882
1883	err = 0;
1884	clnt = fid->clnt;
1885
1886	p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1887
1888	req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1889	if (IS_ERR(req)) {
1890		err = PTR_ERR(req);
1891		goto error;
1892	}
1893
1894	err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1895		&sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1896		&sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1897	if (err) {
1898		trace_9p_protocol_dump(clnt, req->rc);
1899		p9_free_req(clnt, req);
1900		goto error;
1901	}
1902
1903	p9_debug(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1904		"blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1905		"fsid %llu namelen %ld\n",
1906		fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1907		sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1908		sb->fsid, (long int)sb->namelen);
1909
1910	p9_free_req(clnt, req);
1911error:
1912	return err;
1913}
1914EXPORT_SYMBOL(p9_client_statfs);
1915
1916int p9_client_rename(struct p9_fid *fid,
1917		     struct p9_fid *newdirfid, const char *name)
1918{
1919	int err;
1920	struct p9_req_t *req;
1921	struct p9_client *clnt;
1922
1923	err = 0;
1924	clnt = fid->clnt;
1925
1926	p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1927			fid->fid, newdirfid->fid, name);
1928
1929	req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1930			newdirfid->fid, name);
1931	if (IS_ERR(req)) {
1932		err = PTR_ERR(req);
1933		goto error;
1934	}
1935
1936	p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1937
1938	p9_free_req(clnt, req);
1939error:
1940	return err;
1941}
1942EXPORT_SYMBOL(p9_client_rename);
1943
1944int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1945		       struct p9_fid *newdirfid, const char *new_name)
1946{
1947	int err;
1948	struct p9_req_t *req;
1949	struct p9_client *clnt;
1950
1951	err = 0;
1952	clnt = olddirfid->clnt;
1953
1954	p9_debug(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1955		   " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1956		   newdirfid->fid, new_name);
1957
1958	req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1959			    old_name, newdirfid->fid, new_name);
1960	if (IS_ERR(req)) {
1961		err = PTR_ERR(req);
1962		goto error;
1963	}
1964
1965	p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
1966		   newdirfid->fid, new_name);
1967
1968	p9_free_req(clnt, req);
1969error:
1970	return err;
1971}
1972EXPORT_SYMBOL(p9_client_renameat);
1973
1974/*
1975 * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1976 */
1977struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1978				const char *attr_name, u64 *attr_size)
1979{
1980	int err;
1981	struct p9_req_t *req;
1982	struct p9_client *clnt;
1983	struct p9_fid *attr_fid;
1984
1985	err = 0;
1986	clnt = file_fid->clnt;
1987	attr_fid = p9_fid_create(clnt);
1988	if (IS_ERR(attr_fid)) {
1989		err = PTR_ERR(attr_fid);
1990		attr_fid = NULL;
1991		goto error;
1992	}
1993	p9_debug(P9_DEBUG_9P,
1994		">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
1995		file_fid->fid, attr_fid->fid, attr_name);
1996
1997	req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
1998			file_fid->fid, attr_fid->fid, attr_name);
1999	if (IS_ERR(req)) {
2000		err = PTR_ERR(req);
2001		goto error;
2002	}
2003	err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
2004	if (err) {
2005		trace_9p_protocol_dump(clnt, req->rc);
2006		p9_free_req(clnt, req);
2007		goto clunk_fid;
2008	}
2009	p9_free_req(clnt, req);
2010	p9_debug(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
2011		attr_fid->fid, *attr_size);
2012	return attr_fid;
2013clunk_fid:
2014	p9_client_clunk(attr_fid);
2015	attr_fid = NULL;
2016error:
2017	if (attr_fid && (attr_fid != file_fid))
2018		p9_fid_destroy(attr_fid);
2019
2020	return ERR_PTR(err);
2021}
2022EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
2023
2024int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
2025			u64 attr_size, int flags)
2026{
2027	int err;
2028	struct p9_req_t *req;
2029	struct p9_client *clnt;
2030
2031	p9_debug(P9_DEBUG_9P,
2032		">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
2033		fid->fid, name, (long long)attr_size, flags);
2034	err = 0;
2035	clnt = fid->clnt;
2036	req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2037			fid->fid, name, attr_size, flags);
2038	if (IS_ERR(req)) {
2039		err = PTR_ERR(req);
2040		goto error;
2041	}
2042	p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2043	p9_free_req(clnt, req);
2044error:
2045	return err;
2046}
2047EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2048
2049int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2050{
2051	int err, rsize, non_zc = 0;
2052	struct p9_client *clnt;
2053	struct p9_req_t *req;
2054	char *dataptr;
2055	struct kvec kv = {.iov_base = data, .iov_len = count};
2056	struct iov_iter to;
2057
2058	iov_iter_kvec(&to, READ | ITER_KVEC, &kv, 1, count);
2059
2060	p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2061				fid->fid, (unsigned long long) offset, count);
2062
2063	err = 0;
2064	clnt = fid->clnt;
2065
2066	rsize = fid->iounit;
2067	if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2068		rsize = clnt->msize - P9_READDIRHDRSZ;
2069
2070	if (count < rsize)
2071		rsize = count;
2072
2073	/* Don't bother zerocopy for small IO (< 1024) */
2074	if (clnt->trans_mod->zc_request && rsize > 1024) {
2075		/*
2076		 * response header len is 11
2077		 * PDU Header(7) + IO Size (4)
2078		 */
2079		req = p9_client_zc_rpc(clnt, P9_TREADDIR, &to, NULL, rsize, 0,
2080				       11, "dqd", fid->fid, offset, rsize);
2081	} else {
2082		non_zc = 1;
2083		req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2084				    offset, rsize);
2085	}
2086	if (IS_ERR(req)) {
2087		err = PTR_ERR(req);
2088		goto error;
2089	}
2090
2091	err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2092	if (err) {
2093		trace_9p_protocol_dump(clnt, req->rc);
2094		goto free_and_error;
2095	}
2096
2097	p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2098
2099	if (non_zc)
2100		memmove(data, dataptr, count);
2101
2102	p9_free_req(clnt, req);
2103	return count;
2104
2105free_and_error:
2106	p9_free_req(clnt, req);
2107error:
2108	return err;
2109}
2110EXPORT_SYMBOL(p9_client_readdir);
2111
2112int p9_client_mknod_dotl(struct p9_fid *fid, char *name, int mode,
2113			dev_t rdev, kgid_t gid, struct p9_qid *qid)
2114{
2115	int err;
2116	struct p9_client *clnt;
2117	struct p9_req_t *req;
2118
2119	err = 0;
2120	clnt = fid->clnt;
2121	p9_debug(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2122		"minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2123	req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddg", fid->fid, name, mode,
2124		MAJOR(rdev), MINOR(rdev), gid);
2125	if (IS_ERR(req))
2126		return PTR_ERR(req);
2127
2128	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2129	if (err) {
2130		trace_9p_protocol_dump(clnt, req->rc);
2131		goto error;
2132	}
2133	p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2134				(unsigned long long)qid->path, qid->version);
2135
2136error:
2137	p9_free_req(clnt, req);
2138	return err;
2139
2140}
2141EXPORT_SYMBOL(p9_client_mknod_dotl);
2142
2143int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
2144				kgid_t gid, struct p9_qid *qid)
2145{
2146	int err;
2147	struct p9_client *clnt;
2148	struct p9_req_t *req;
2149
2150	err = 0;
2151	clnt = fid->clnt;
2152	p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2153		 fid->fid, name, mode, from_kgid(&init_user_ns, gid));
2154	req = p9_client_rpc(clnt, P9_TMKDIR, "dsdg", fid->fid, name, mode,
2155		gid);
2156	if (IS_ERR(req))
2157		return PTR_ERR(req);
2158
2159	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2160	if (err) {
2161		trace_9p_protocol_dump(clnt, req->rc);
2162		goto error;
2163	}
2164	p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2165				(unsigned long long)qid->path, qid->version);
2166
2167error:
2168	p9_free_req(clnt, req);
2169	return err;
2170
2171}
2172EXPORT_SYMBOL(p9_client_mkdir_dotl);
2173
2174int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2175{
2176	int err;
2177	struct p9_client *clnt;
2178	struct p9_req_t *req;
2179
2180	err = 0;
2181	clnt = fid->clnt;
2182	p9_debug(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2183			"start %lld length %lld proc_id %d client_id %s\n",
2184			fid->fid, flock->type, flock->flags, flock->start,
2185			flock->length, flock->proc_id, flock->client_id);
2186
2187	req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2188				flock->flags, flock->start, flock->length,
2189					flock->proc_id, flock->client_id);
2190
2191	if (IS_ERR(req))
2192		return PTR_ERR(req);
2193
2194	err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2195	if (err) {
2196		trace_9p_protocol_dump(clnt, req->rc);
2197		goto error;
2198	}
2199	p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2200error:
2201	p9_free_req(clnt, req);
2202	return err;
2203
2204}
2205EXPORT_SYMBOL(p9_client_lock_dotl);
2206
2207int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2208{
2209	int err;
2210	struct p9_client *clnt;
2211	struct p9_req_t *req;
2212
2213	err = 0;
2214	clnt = fid->clnt;
2215	p9_debug(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
2216		"length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2217		glock->start, glock->length, glock->proc_id, glock->client_id);
2218
2219	req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
2220		glock->start, glock->length, glock->proc_id, glock->client_id);
2221
2222	if (IS_ERR(req))
2223		return PTR_ERR(req);
2224
2225	err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2226			&glock->start, &glock->length, &glock->proc_id,
2227			&glock->client_id);
2228	if (err) {
2229		trace_9p_protocol_dump(clnt, req->rc);
2230		goto error;
2231	}
2232	p9_debug(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2233		"proc_id %d client_id %s\n", glock->type, glock->start,
2234		glock->length, glock->proc_id, glock->client_id);
2235error:
2236	p9_free_req(clnt, req);
2237	return err;
2238}
2239EXPORT_SYMBOL(p9_client_getlock_dotl);
2240
2241int p9_client_readlink(struct p9_fid *fid, char **target)
2242{
2243	int err;
2244	struct p9_client *clnt;
2245	struct p9_req_t *req;
2246
2247	err = 0;
2248	clnt = fid->clnt;
2249	p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2250
2251	req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2252	if (IS_ERR(req))
2253		return PTR_ERR(req);
2254
2255	err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2256	if (err) {
2257		trace_9p_protocol_dump(clnt, req->rc);
2258		goto error;
2259	}
2260	p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2261error:
2262	p9_free_req(clnt, req);
2263	return err;
2264}
2265EXPORT_SYMBOL(p9_client_readlink);
2266