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/signal.h>
  36#include <linux/uaccess.h>
  37#include <linux/uio.h>
  38#include <net/9p/9p.h>
  39#include <linux/parser.h>
  40#include <linux/seq_file.h>
  41#include <net/9p/client.h>
  42#include <net/9p/transport.h>
  43#include "protocol.h"
  44
  45#define CREATE_TRACE_POINTS
  46#include <trace/events/9p.h>
  47
  48/*
  49  * Client Option Parsing (code inspired by NFS code)
  50  *  - a little lazy - parse all client options
  51  */
  52
  53enum {
  54	Opt_msize,
  55	Opt_trans,
  56	Opt_legacy,
  57	Opt_version,
  58	Opt_err,
  59};
  60
  61static const match_table_t tokens = {
  62	{Opt_msize, "msize=%u"},
  63	{Opt_legacy, "noextend"},
  64	{Opt_trans, "trans=%s"},
  65	{Opt_version, "version=%s"},
  66	{Opt_err, NULL},
  67};
  68
  69inline int p9_is_proto_dotl(struct p9_client *clnt)
  70{
  71	return clnt->proto_version == p9_proto_2000L;
  72}
  73EXPORT_SYMBOL(p9_is_proto_dotl);
  74
  75inline int p9_is_proto_dotu(struct p9_client *clnt)
  76{
  77	return clnt->proto_version == p9_proto_2000u;
  78}
  79EXPORT_SYMBOL(p9_is_proto_dotu);
  80
  81int p9_show_client_options(struct seq_file *m, struct p9_client *clnt)
  82{
  83	if (clnt->msize != 8192)
  84		seq_printf(m, ",msize=%u", clnt->msize);
  85	seq_printf(m, ",trans=%s", clnt->trans_mod->name);
  86
  87	switch (clnt->proto_version) {
  88	case p9_proto_legacy:
  89		seq_puts(m, ",noextend");
  90		break;
  91	case p9_proto_2000u:
  92		seq_puts(m, ",version=9p2000.u");
  93		break;
  94	case p9_proto_2000L:
  95		/* Default */
  96		break;
  97	}
  98
  99	if (clnt->trans_mod->show_options)
 100		return clnt->trans_mod->show_options(m, clnt);
 101	return 0;
 102}
 103EXPORT_SYMBOL(p9_show_client_options);
 104
 105/*
 106 * Some error codes are taken directly from the server replies,
 107 * make sure they are valid.
 108 */
 109static int safe_errno(int err)
 110{
 111	if ((err > 0) || (err < -MAX_ERRNO)) {
 112		p9_debug(P9_DEBUG_ERROR, "Invalid error code %d\n", err);
 113		return -EPROTO;
 114	}
 115	return err;
 116}
 117
 118
 119/* Interpret mount option for protocol version */
 120static int get_protocol_version(char *s)
 121{
 122	int version = -EINVAL;
 123
 124	if (!strcmp(s, "9p2000")) {
 125		version = p9_proto_legacy;
 126		p9_debug(P9_DEBUG_9P, "Protocol version: Legacy\n");
 127	} else if (!strcmp(s, "9p2000.u")) {
 128		version = p9_proto_2000u;
 129		p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
 130	} else if (!strcmp(s, "9p2000.L")) {
 131		version = p9_proto_2000L;
 132		p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.L\n");
 133	} else
 134		pr_info("Unknown protocol version %s\n", s);
 135
 136	return version;
 137}
 138
 139/**
 140 * parse_options - parse mount options into client structure
 141 * @opts: options string passed from mount
 142 * @clnt: existing v9fs client information
 143 *
 144 * Return 0 upon success, -ERRNO upon failure
 145 */
 146
 147static int parse_opts(char *opts, struct p9_client *clnt)
 148{
 149	char *options, *tmp_options;
 150	char *p;
 151	substring_t args[MAX_OPT_ARGS];
 152	int option;
 153	char *s;
 154	int ret = 0;
 155
 156	clnt->proto_version = p9_proto_2000L;
 157	clnt->msize = 8192;
 158
 159	if (!opts)
 160		return 0;
 161
 162	tmp_options = kstrdup(opts, GFP_KERNEL);
 163	if (!tmp_options) {
 164		p9_debug(P9_DEBUG_ERROR,
 165			 "failed to allocate copy of option string\n");
 166		return -ENOMEM;
 167	}
 168	options = tmp_options;
 169
 170	while ((p = strsep(&options, ",")) != NULL) {
 171		int token, r;
 172		if (!*p)
 173			continue;
 174		token = match_token(p, tokens, args);
 175		switch (token) {
 176		case Opt_msize:
 177			r = match_int(&args[0], &option);
 178			if (r < 0) {
 179				p9_debug(P9_DEBUG_ERROR,
 180					 "integer field, but no integer?\n");
 181				ret = r;
 182				continue;
 183			}
 
 
 
 
 
 
 184			clnt->msize = option;
 185			break;
 186		case Opt_trans:
 187			s = match_strdup(&args[0]);
 188			if (!s) {
 189				ret = -ENOMEM;
 190				p9_debug(P9_DEBUG_ERROR,
 191					 "problem allocating copy of trans arg\n");
 192				goto free_and_return;
 193			}
 194
 195			v9fs_put_trans(clnt->trans_mod);
 196			clnt->trans_mod = v9fs_get_trans_by_name(s);
 197			if (clnt->trans_mod == NULL) {
 198				pr_info("Could not find request transport: %s\n",
 199					s);
 200				ret = -EINVAL;
 201				kfree(s);
 202				goto free_and_return;
 203			}
 204			kfree(s);
 205			break;
 206		case Opt_legacy:
 207			clnt->proto_version = p9_proto_legacy;
 208			break;
 209		case Opt_version:
 210			s = match_strdup(&args[0]);
 211			if (!s) {
 212				ret = -ENOMEM;
 213				p9_debug(P9_DEBUG_ERROR,
 214					 "problem allocating copy of version arg\n");
 215				goto free_and_return;
 216			}
 217			ret = get_protocol_version(s);
 218			if (ret == -EINVAL) {
 219				kfree(s);
 220				goto free_and_return;
 221			}
 222			kfree(s);
 223			clnt->proto_version = ret;
 224			break;
 225		default:
 226			continue;
 227		}
 228	}
 229
 230free_and_return:
 231	v9fs_put_trans(clnt->trans_mod);
 
 232	kfree(tmp_options);
 233	return ret;
 234}
 235
 236static struct p9_fcall *p9_fcall_alloc(int alloc_msize)
 
 237{
 238	struct p9_fcall *fc;
 239	fc = kmalloc(sizeof(struct p9_fcall) + alloc_msize, GFP_NOFS);
 240	if (!fc)
 241		return NULL;
 
 
 
 
 
 242	fc->capacity = alloc_msize;
 243	fc->sdata = (char *) fc + sizeof(struct p9_fcall);
 244	return fc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 245}
 
 
 
 246
 247/**
 248 * p9_tag_alloc - lookup/allocate a request by tag
 249 * @c: client session to lookup tag within
 250 * @tag: numeric id for transaction
 251 *
 252 * this is a simple array lookup, but will grow the
 253 * request_slots as necessary to accommodate transaction
 254 * ids which did not previously have a slot.
 255 *
 256 * this code relies on the client spinlock to manage locks, its
 257 * possible we should switch to something else, but I'd rather
 258 * stick with something low-overhead for the common case.
 259 *
 
 
 260 */
 261
 262static struct p9_req_t *
 263p9_tag_alloc(struct p9_client *c, u16 tag, unsigned int max_size)
 264{
 265	unsigned long flags;
 266	int row, col;
 267	struct p9_req_t *req;
 268	int alloc_msize = min(c->msize, max_size);
 
 269
 270	/* This looks up the original request by tag so we know which
 271	 * buffer to read the data into */
 272	tag++;
 273
 274	if (tag >= c->max_tag) {
 275		spin_lock_irqsave(&c->lock, flags);
 276		/* check again since original check was outside of lock */
 277		while (tag >= c->max_tag) {
 278			row = (tag / P9_ROW_MAXTAG);
 279			c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
 280					sizeof(struct p9_req_t), GFP_ATOMIC);
 281
 282			if (!c->reqs[row]) {
 283				pr_err("Couldn't grow tag array\n");
 284				spin_unlock_irqrestore(&c->lock, flags);
 285				return ERR_PTR(-ENOMEM);
 286			}
 287			for (col = 0; col < P9_ROW_MAXTAG; col++) {
 288				c->reqs[row][col].status = REQ_STATUS_IDLE;
 289				c->reqs[row][col].tc = NULL;
 290			}
 291			c->max_tag += P9_ROW_MAXTAG;
 292		}
 293		spin_unlock_irqrestore(&c->lock, flags);
 294	}
 295	row = tag / P9_ROW_MAXTAG;
 296	col = tag % P9_ROW_MAXTAG;
 297
 298	req = &c->reqs[row][col];
 299	if (!req->wq) {
 300		req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_NOFS);
 301		if (!req->wq)
 302			goto grow_failed;
 303		init_waitqueue_head(req->wq);
 304	}
 305
 306	if (!req->tc)
 307		req->tc = p9_fcall_alloc(alloc_msize);
 308	if (!req->rc)
 309		req->rc = p9_fcall_alloc(alloc_msize);
 310	if (!req->tc || !req->rc)
 311		goto grow_failed;
 312
 313	p9pdu_reset(req->tc);
 314	p9pdu_reset(req->rc);
 315
 316	req->tc->tag = tag-1;
 
 
 
 
 
 
 
 317	req->status = REQ_STATUS_ALLOC;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 318
 319	return req;
 320
 321grow_failed:
 322	pr_err("Couldn't grow tag array\n");
 323	kfree(req->tc);
 324	kfree(req->rc);
 325	kfree(req->wq);
 326	req->tc = req->rc = NULL;
 327	req->wq = NULL;
 328	return ERR_PTR(-ENOMEM);
 329}
 330
 331/**
 332 * p9_tag_lookup - lookup a request by tag
 333 * @c: client session to lookup tag within
 334 * @tag: numeric id for transaction
 335 *
 
 
 336 */
 337
 338struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
 339{
 340	int row, col;
 341
 342	/* This looks up the original request by tag so we know which
 343	 * buffer to read the data into */
 344	tag++;
 345
 346	if(tag >= c->max_tag) 
 347		return NULL;
 348
 349	row = tag / P9_ROW_MAXTAG;
 350	col = tag % P9_ROW_MAXTAG;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 351
 352	return &c->reqs[row][col];
 353}
 354EXPORT_SYMBOL(p9_tag_lookup);
 355
 356/**
 357 * p9_tag_init - setup tags structure and contents
 358 * @c:  v9fs client struct
 359 *
 360 * This initializes the tags structure for each client instance.
 361 *
 
 362 */
 
 
 
 
 363
 364static int p9_tag_init(struct p9_client *c)
 
 
 
 
 
 
 
 365{
 366	int err = 0;
 
 
 
 
 367
 368	c->tagpool = p9_idpool_create();
 369	if (IS_ERR(c->tagpool)) {
 370		err = PTR_ERR(c->tagpool);
 371		goto error;
 372	}
 373	err = p9_idpool_get(c->tagpool); /* reserve tag 0 */
 374	if (err < 0) {
 375		p9_idpool_destroy(c->tagpool);
 376		goto error;
 377	}
 378	c->max_tag = 0;
 379error:
 380	return err;
 381}
 
 382
 383/**
 384 * p9_tag_cleanup - cleans up tags structure and reclaims resources
 385 * @c:  v9fs client struct
 386 *
 387 * This frees resources associated with the tags structure
 388 *
 389 */
 390static void p9_tag_cleanup(struct p9_client *c)
 391{
 392	int row, col;
 393
 394	/* check to insure all requests are idle */
 395	for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 396		for (col = 0; col < P9_ROW_MAXTAG; col++) {
 397			if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
 398				p9_debug(P9_DEBUG_MUX,
 399					 "Attempting to cleanup non-free tag %d,%d\n",
 400					 row, col);
 401				/* TODO: delay execution of cleanup */
 402				return;
 403			}
 404		}
 405	}
 406
 407	if (c->tagpool) {
 408		p9_idpool_put(0, c->tagpool); /* free reserved tag 0 */
 409		p9_idpool_destroy(c->tagpool);
 410	}
 411
 412	/* free requests associated with tags */
 413	for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 414		for (col = 0; col < P9_ROW_MAXTAG; col++) {
 415			kfree(c->reqs[row][col].wq);
 416			kfree(c->reqs[row][col].tc);
 417			kfree(c->reqs[row][col].rc);
 418		}
 419		kfree(c->reqs[row]);
 420	}
 421	c->max_tag = 0;
 422}
 423
 424/**
 425 * p9_free_req - free a request and clean-up as necessary
 426 * c: client state
 427 * r: request to release
 428 *
 429 */
 430
 431static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
 432{
 433	int tag = r->tc->tag;
 434	p9_debug(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
 435
 436	r->status = REQ_STATUS_IDLE;
 437	if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
 438		p9_idpool_put(tag, c->tagpool);
 439}
 440
 441/**
 442 * p9_client_cb - call back from transport to client
 443 * c: client state
 444 * req: request received
 445 *
 446 */
 447void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status)
 448{
 449	p9_debug(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
 450
 451	/*
 452	 * This barrier is needed to make sure any change made to req before
 453	 * the other thread wakes up will indeed be seen by the waiting side.
 454	 */
 455	smp_wmb();
 456	req->status = status;
 457
 458	wake_up(req->wq);
 459	p9_debug(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
 
 460}
 461EXPORT_SYMBOL(p9_client_cb);
 462
 463/**
 464 * p9_parse_header - parse header arguments out of a packet
 465 * @pdu: packet to parse
 466 * @size: size of packet
 467 * @type: type of request
 468 * @tag: tag of packet
 469 * @rewind: set if we need to rewind offset afterwards
 470 */
 471
 472int
 473p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
 474								int rewind)
 475{
 476	int8_t r_type;
 477	int16_t r_tag;
 478	int32_t r_size;
 479	int offset = pdu->offset;
 480	int err;
 481
 482	pdu->offset = 0;
 483	if (pdu->size == 0)
 484		pdu->size = 7;
 485
 486	err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
 487	if (err)
 488		goto rewind_and_exit;
 489
 490	pdu->size = r_size;
 491	pdu->id = r_type;
 492	pdu->tag = r_tag;
 493
 494	p9_debug(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n",
 495		 pdu->size, pdu->id, pdu->tag);
 496
 497	if (type)
 498		*type = r_type;
 499	if (tag)
 500		*tag = r_tag;
 501	if (size)
 502		*size = r_size;
 503
 
 
 
 
 
 
 
 
 
 
 504
 505rewind_and_exit:
 506	if (rewind)
 507		pdu->offset = offset;
 508	return err;
 509}
 510EXPORT_SYMBOL(p9_parse_header);
 511
 512/**
 513 * p9_check_errors - check 9p packet for error return and process it
 514 * @c: current client instance
 515 * @req: request to parse and check for error conditions
 516 *
 517 * returns error code if one is discovered, otherwise returns 0
 518 *
 519 * this will have to be more complicated if we have multiple
 520 * error packet types
 521 */
 522
 523static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 524{
 525	int8_t type;
 526	int err;
 527	int ecode;
 528
 529	err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 
 
 
 
 
 
 530	/*
 531	 * dump the response from server
 532	 * This should be after check errors which poplulate pdu_fcall.
 533	 */
 534	trace_9p_protocol_dump(c, req->rc);
 535	if (err) {
 536		p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 537		return err;
 538	}
 539	if (type != P9_RERROR && type != P9_RLERROR)
 540		return 0;
 541
 542	if (!p9_is_proto_dotl(c)) {
 543		char *ename;
 544		err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 545				  &ename, &ecode);
 546		if (err)
 547			goto out_err;
 548
 549		if (p9_is_proto_dotu(c) && ecode < 512)
 550			err = -ecode;
 551
 552		if (!err) {
 553			err = p9_errstr2errno(ename, strlen(ename));
 554
 555			p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 556				 -ecode, ename);
 557		}
 558		kfree(ename);
 559	} else {
 560		err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 561		err = -ecode;
 562
 563		p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 564	}
 565
 566	return err;
 567
 568out_err:
 569	p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 570
 571	return err;
 572}
 573
 574/**
 575 * p9_check_zc_errors - check 9p packet for error return and process it
 576 * @c: current client instance
 577 * @req: request to parse and check for error conditions
 578 * @in_hdrlen: Size of response protocol buffer.
 579 *
 580 * returns error code if one is discovered, otherwise returns 0
 581 *
 582 * this will have to be more complicated if we have multiple
 583 * error packet types
 584 */
 585
 586static int p9_check_zc_errors(struct p9_client *c, struct p9_req_t *req,
 587			      struct iov_iter *uidata, int in_hdrlen)
 588{
 589	int err;
 590	int ecode;
 591	int8_t type;
 592	char *ename = NULL;
 593
 594	err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 595	/*
 596	 * dump the response from server
 597	 * This should be after parse_header which poplulate pdu_fcall.
 598	 */
 599	trace_9p_protocol_dump(c, req->rc);
 600	if (err) {
 601		p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 602		return err;
 603	}
 604
 605	if (type != P9_RERROR && type != P9_RLERROR)
 606		return 0;
 607
 608	if (!p9_is_proto_dotl(c)) {
 609		/* Error is reported in string format */
 610		int len;
 611		/* 7 = header size for RERROR; */
 612		int inline_len = in_hdrlen - 7;
 613
 614		len =  req->rc->size - req->rc->offset;
 615		if (len > (P9_ZC_HDR_SZ - 7)) {
 616			err = -EFAULT;
 617			goto out_err;
 618		}
 619
 620		ename = &req->rc->sdata[req->rc->offset];
 621		if (len > inline_len) {
 622			/* We have error in external buffer */
 623			if (!copy_from_iter_full(ename + inline_len,
 624					     len - inline_len, uidata)) {
 625				err = -EFAULT;
 626				goto out_err;
 627			}
 628		}
 629		ename = NULL;
 630		err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 631				  &ename, &ecode);
 632		if (err)
 633			goto out_err;
 634
 635		if (p9_is_proto_dotu(c) && ecode < 512)
 636			err = -ecode;
 637
 638		if (!err) {
 639			err = p9_errstr2errno(ename, strlen(ename));
 640
 641			p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 642				 -ecode, ename);
 643		}
 644		kfree(ename);
 645	} else {
 646		err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 647		err = -ecode;
 648
 649		p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 650	}
 651	return err;
 652
 653out_err:
 654	p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 655	return err;
 656}
 657
 658static struct p9_req_t *
 659p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
 660
 661/**
 662 * p9_client_flush - flush (cancel) a request
 663 * @c: client state
 664 * @oldreq: request to cancel
 665 *
 666 * This sents a flush for a particular request and links
 667 * the flush request to the original request.  The current
 668 * code only supports a single flush request although the protocol
 669 * allows for multiple flush requests to be sent for a single request.
 670 *
 671 */
 672
 673static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 674{
 675	struct p9_req_t *req;
 676	int16_t oldtag;
 677	int err;
 678
 679	err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
 680	if (err)
 681		return err;
 682
 683	p9_debug(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
 684
 685	req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
 686	if (IS_ERR(req))
 687		return PTR_ERR(req);
 688
 689	/*
 690	 * if we haven't received a response for oldreq,
 691	 * remove it from the list
 692	 */
 693	if (oldreq->status == REQ_STATUS_SENT)
 694		if (c->trans_mod->cancelled)
 695			c->trans_mod->cancelled(c, oldreq);
 
 696
 697	p9_free_req(c, req);
 698	return 0;
 699}
 700
 701static struct p9_req_t *p9_client_prepare_req(struct p9_client *c,
 702					      int8_t type, int req_size,
 703					      const char *fmt, va_list ap)
 704{
 705	int tag, err;
 706	struct p9_req_t *req;
 707
 708	p9_debug(P9_DEBUG_MUX, "client %p op %d\n", c, type);
 709
 710	/* we allow for any status other than disconnected */
 711	if (c->status == Disconnected)
 712		return ERR_PTR(-EIO);
 713
 714	/* if status is begin_disconnected we allow only clunk request */
 715	if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
 716		return ERR_PTR(-EIO);
 717
 718	tag = P9_NOTAG;
 719	if (type != P9_TVERSION) {
 720		tag = p9_idpool_get(c->tagpool);
 721		if (tag < 0)
 722			return ERR_PTR(-ENOMEM);
 723	}
 724
 725	req = p9_tag_alloc(c, tag, req_size);
 726	if (IS_ERR(req))
 727		return req;
 728
 729	/* marshall the data */
 730	p9pdu_prepare(req->tc, tag, type);
 731	err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
 732	if (err)
 733		goto reterr;
 734	p9pdu_finalize(c, req->tc);
 735	trace_9p_client_req(c, type, tag);
 736	return req;
 737reterr:
 738	p9_free_req(c, req);
 
 
 739	return ERR_PTR(err);
 740}
 741
 742/**
 743 * p9_client_rpc - issue a request and wait for a response
 744 * @c: client session
 745 * @type: type of request
 746 * @fmt: protocol format string (see protocol.c)
 747 *
 748 * Returns request structure (which client must free using p9_free_req)
 749 */
 750
 751static struct p9_req_t *
 752p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 753{
 754	va_list ap;
 755	int sigpending, err;
 756	unsigned long flags;
 757	struct p9_req_t *req;
 758
 759	va_start(ap, fmt);
 760	req = p9_client_prepare_req(c, type, c->msize, fmt, ap);
 761	va_end(ap);
 762	if (IS_ERR(req))
 763		return req;
 764
 765	if (signal_pending(current)) {
 766		sigpending = 1;
 767		clear_thread_flag(TIF_SIGPENDING);
 768	} else
 769		sigpending = 0;
 770
 771	err = c->trans_mod->request(c, req);
 772	if (err < 0) {
 
 
 773		if (err != -ERESTARTSYS && err != -EFAULT)
 774			c->status = Disconnected;
 775		goto recalc_sigpending;
 776	}
 777again:
 778	/* Wait for the response */
 779	err = wait_event_killable(*req->wq, req->status >= REQ_STATUS_RCVD);
 780
 781	/*
 782	 * Make sure our req is coherent with regard to updates in other
 783	 * threads - echoes to wmb() in the callback
 784	 */
 785	smp_rmb();
 786
 787	if ((err == -ERESTARTSYS) && (c->status == Connected)
 788				  && (type == P9_TFLUSH)) {
 789		sigpending = 1;
 790		clear_thread_flag(TIF_SIGPENDING);
 791		goto again;
 792	}
 793
 794	if (req->status == REQ_STATUS_ERROR) {
 795		p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 796		err = req->t_err;
 797	}
 798	if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 799		p9_debug(P9_DEBUG_MUX, "flushing\n");
 800		sigpending = 1;
 801		clear_thread_flag(TIF_SIGPENDING);
 802
 803		if (c->trans_mod->cancel(c, req))
 804			p9_client_flush(c, req);
 805
 806		/* if we received the response anyway, don't signal error */
 807		if (req->status == REQ_STATUS_RCVD)
 808			err = 0;
 809	}
 810recalc_sigpending:
 811	if (sigpending) {
 812		spin_lock_irqsave(&current->sighand->siglock, flags);
 813		recalc_sigpending();
 814		spin_unlock_irqrestore(&current->sighand->siglock, flags);
 815	}
 816	if (err < 0)
 817		goto reterr;
 818
 819	err = p9_check_errors(c, req);
 820	trace_9p_client_res(c, type, req->rc->tag, err);
 821	if (!err)
 822		return req;
 823reterr:
 824	p9_free_req(c, req);
 825	return ERR_PTR(safe_errno(err));
 826}
 827
 828/**
 829 * p9_client_zc_rpc - issue a request and wait for a response
 830 * @c: client session
 831 * @type: type of request
 832 * @uidata: destination for zero copy read
 833 * @uodata: source for zero copy write
 834 * @inlen: read buffer size
 835 * @olen: write buffer size
 836 * @hdrlen: reader header size, This is the size of response protocol data
 837 * @fmt: protocol format string (see protocol.c)
 838 *
 839 * Returns request structure (which client must free using p9_free_req)
 840 */
 841static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
 842					 struct iov_iter *uidata,
 843					 struct iov_iter *uodata,
 844					 int inlen, int olen, int in_hdrlen,
 845					 const char *fmt, ...)
 846{
 847	va_list ap;
 848	int sigpending, err;
 849	unsigned long flags;
 850	struct p9_req_t *req;
 851
 852	va_start(ap, fmt);
 853	/*
 854	 * We allocate a inline protocol data of only 4k bytes.
 855	 * The actual content is passed in zero-copy fashion.
 856	 */
 857	req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, fmt, ap);
 858	va_end(ap);
 859	if (IS_ERR(req))
 860		return req;
 861
 862	if (signal_pending(current)) {
 863		sigpending = 1;
 864		clear_thread_flag(TIF_SIGPENDING);
 865	} else
 866		sigpending = 0;
 867
 868	err = c->trans_mod->zc_request(c, req, uidata, uodata,
 869				       inlen, olen, in_hdrlen);
 870	if (err < 0) {
 871		if (err == -EIO)
 872			c->status = Disconnected;
 873		if (err != -ERESTARTSYS)
 874			goto recalc_sigpending;
 875	}
 876	if (req->status == REQ_STATUS_ERROR) {
 877		p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 878		err = req->t_err;
 879	}
 880	if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 881		p9_debug(P9_DEBUG_MUX, "flushing\n");
 882		sigpending = 1;
 883		clear_thread_flag(TIF_SIGPENDING);
 884
 885		if (c->trans_mod->cancel(c, req))
 886			p9_client_flush(c, req);
 887
 888		/* if we received the response anyway, don't signal error */
 889		if (req->status == REQ_STATUS_RCVD)
 890			err = 0;
 891	}
 892recalc_sigpending:
 893	if (sigpending) {
 894		spin_lock_irqsave(&current->sighand->siglock, flags);
 895		recalc_sigpending();
 896		spin_unlock_irqrestore(&current->sighand->siglock, flags);
 897	}
 898	if (err < 0)
 899		goto reterr;
 900
 901	err = p9_check_zc_errors(c, req, uidata, in_hdrlen);
 902	trace_9p_client_res(c, type, req->rc->tag, err);
 903	if (!err)
 904		return req;
 905reterr:
 906	p9_free_req(c, req);
 907	return ERR_PTR(safe_errno(err));
 908}
 909
 910static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 911{
 912	int ret;
 913	struct p9_fid *fid;
 914	unsigned long flags;
 915
 916	p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt);
 917	fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
 918	if (!fid)
 919		return ERR_PTR(-ENOMEM);
 920
 921	ret = p9_idpool_get(clnt->fidpool);
 922	if (ret < 0) {
 923		ret = -ENOSPC;
 924		goto error;
 925	}
 926	fid->fid = ret;
 927
 928	memset(&fid->qid, 0, sizeof(struct p9_qid));
 929	fid->mode = -1;
 930	fid->uid = current_fsuid();
 931	fid->clnt = clnt;
 932	fid->rdir = NULL;
 933	spin_lock_irqsave(&clnt->lock, flags);
 934	list_add(&fid->flist, &clnt->fidlist);
 935	spin_unlock_irqrestore(&clnt->lock, flags);
 936
 937	return fid;
 
 
 
 
 
 
 
 
 938
 939error:
 940	kfree(fid);
 941	return ERR_PTR(ret);
 942}
 943
 944static void p9_fid_destroy(struct p9_fid *fid)
 945{
 946	struct p9_client *clnt;
 947	unsigned long flags;
 948
 949	p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
 950	clnt = fid->clnt;
 951	p9_idpool_put(fid->fid, clnt->fidpool);
 952	spin_lock_irqsave(&clnt->lock, flags);
 953	list_del(&fid->flist);
 954	spin_unlock_irqrestore(&clnt->lock, flags);
 955	kfree(fid->rdir);
 956	kfree(fid);
 957}
 958
 959static int p9_client_version(struct p9_client *c)
 960{
 961	int err = 0;
 962	struct p9_req_t *req;
 963	char *version;
 964	int msize;
 965
 966	p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
 967		 c->msize, c->proto_version);
 968
 969	switch (c->proto_version) {
 970	case p9_proto_2000L:
 971		req = p9_client_rpc(c, P9_TVERSION, "ds",
 972					c->msize, "9P2000.L");
 973		break;
 974	case p9_proto_2000u:
 975		req = p9_client_rpc(c, P9_TVERSION, "ds",
 976					c->msize, "9P2000.u");
 977		break;
 978	case p9_proto_legacy:
 979		req = p9_client_rpc(c, P9_TVERSION, "ds",
 980					c->msize, "9P2000");
 981		break;
 982	default:
 983		return -EINVAL;
 984	}
 985
 986	if (IS_ERR(req))
 987		return PTR_ERR(req);
 988
 989	err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
 990	if (err) {
 991		p9_debug(P9_DEBUG_9P, "version error %d\n", err);
 992		trace_9p_protocol_dump(c, req->rc);
 993		goto error;
 994	}
 995
 996	p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
 997	if (!strncmp(version, "9P2000.L", 8))
 998		c->proto_version = p9_proto_2000L;
 999	else if (!strncmp(version, "9P2000.u", 8))
1000		c->proto_version = p9_proto_2000u;
1001	else if (!strncmp(version, "9P2000", 6))
1002		c->proto_version = p9_proto_legacy;
1003	else {
 
 
1004		err = -EREMOTEIO;
1005		goto error;
1006	}
1007
 
 
 
 
 
 
1008	if (msize < c->msize)
1009		c->msize = msize;
1010
1011error:
1012	kfree(version);
1013	p9_free_req(c, req);
1014
1015	return err;
1016}
1017
1018struct p9_client *p9_client_create(const char *dev_name, char *options)
1019{
1020	int err;
1021	struct p9_client *clnt;
1022	char *client_id;
1023
1024	err = 0;
1025	clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
1026	if (!clnt)
1027		return ERR_PTR(-ENOMEM);
1028
1029	clnt->trans_mod = NULL;
1030	clnt->trans = NULL;
 
1031
1032	client_id = utsname()->nodename;
1033	memcpy(clnt->name, client_id, strlen(client_id) + 1);
1034
1035	spin_lock_init(&clnt->lock);
1036	INIT_LIST_HEAD(&clnt->fidlist);
1037
1038	err = p9_tag_init(clnt);
1039	if (err < 0)
1040		goto free_client;
1041
1042	err = parse_opts(options, clnt);
1043	if (err < 0)
1044		goto destroy_tagpool;
1045
1046	if (!clnt->trans_mod)
1047		clnt->trans_mod = v9fs_get_default_trans();
1048
1049	if (clnt->trans_mod == NULL) {
1050		err = -EPROTONOSUPPORT;
1051		p9_debug(P9_DEBUG_ERROR,
1052			 "No transport defined or default transport\n");
1053		goto destroy_tagpool;
1054	}
1055
1056	clnt->fidpool = p9_idpool_create();
1057	if (IS_ERR(clnt->fidpool)) {
1058		err = PTR_ERR(clnt->fidpool);
1059		goto put_trans;
1060	}
1061
1062	p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1063		 clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1064
1065	err = clnt->trans_mod->create(clnt, dev_name, options);
1066	if (err)
1067		goto destroy_fidpool;
1068
1069	if (clnt->msize > clnt->trans_mod->maxsize)
1070		clnt->msize = clnt->trans_mod->maxsize;
1071
 
 
 
 
 
 
 
1072	err = p9_client_version(clnt);
1073	if (err)
1074		goto close_trans;
1075
 
 
 
 
 
 
 
 
 
1076	return clnt;
1077
1078close_trans:
1079	clnt->trans_mod->close(clnt);
1080destroy_fidpool:
1081	p9_idpool_destroy(clnt->fidpool);
1082put_trans:
1083	v9fs_put_trans(clnt->trans_mod);
1084destroy_tagpool:
1085	p9_idpool_destroy(clnt->tagpool);
1086free_client:
1087	kfree(clnt);
1088	return ERR_PTR(err);
1089}
1090EXPORT_SYMBOL(p9_client_create);
1091
1092void p9_client_destroy(struct p9_client *clnt)
1093{
1094	struct p9_fid *fid, *fidptr;
 
1095
1096	p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
1097
1098	if (clnt->trans_mod)
1099		clnt->trans_mod->close(clnt);
1100
1101	v9fs_put_trans(clnt->trans_mod);
1102
1103	list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
1104		pr_info("Found fid %d not clunked\n", fid->fid);
1105		p9_fid_destroy(fid);
1106	}
1107
1108	if (clnt->fidpool)
1109		p9_idpool_destroy(clnt->fidpool);
1110
1111	p9_tag_cleanup(clnt);
1112
 
1113	kfree(clnt);
1114}
1115EXPORT_SYMBOL(p9_client_destroy);
1116
1117void p9_client_disconnect(struct p9_client *clnt)
1118{
1119	p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1120	clnt->status = Disconnected;
1121}
1122EXPORT_SYMBOL(p9_client_disconnect);
1123
1124void p9_client_begin_disconnect(struct p9_client *clnt)
1125{
1126	p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1127	clnt->status = BeginDisconnect;
1128}
1129EXPORT_SYMBOL(p9_client_begin_disconnect);
1130
1131struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1132	const char *uname, kuid_t n_uname, const char *aname)
1133{
1134	int err = 0;
1135	struct p9_req_t *req;
1136	struct p9_fid *fid;
1137	struct p9_qid qid;
1138
1139
1140	p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1141		 afid ? afid->fid : -1, uname, aname);
1142	fid = p9_fid_create(clnt);
1143	if (IS_ERR(fid)) {
1144		err = PTR_ERR(fid);
1145		fid = NULL;
1146		goto error;
1147	}
1148	fid->uid = n_uname;
1149
1150	req = p9_client_rpc(clnt, P9_TATTACH, "ddss?u", fid->fid,
1151			afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1152	if (IS_ERR(req)) {
1153		err = PTR_ERR(req);
1154		goto error;
1155	}
1156
1157	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
1158	if (err) {
1159		trace_9p_protocol_dump(clnt, req->rc);
1160		p9_free_req(clnt, req);
1161		goto error;
1162	}
1163
1164	p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1165		 qid.type, (unsigned long long)qid.path, qid.version);
1166
1167	memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1168
1169	p9_free_req(clnt, req);
1170	return fid;
1171
1172error:
1173	if (fid)
1174		p9_fid_destroy(fid);
1175	return ERR_PTR(err);
1176}
1177EXPORT_SYMBOL(p9_client_attach);
1178
1179struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1180		const unsigned char * const *wnames, int clone)
1181{
1182	int err;
1183	struct p9_client *clnt;
1184	struct p9_fid *fid;
1185	struct p9_qid *wqids;
1186	struct p9_req_t *req;
1187	uint16_t nwqids, count;
1188
1189	err = 0;
1190	wqids = NULL;
1191	clnt = oldfid->clnt;
1192	if (clone) {
1193		fid = p9_fid_create(clnt);
1194		if (IS_ERR(fid)) {
1195			err = PTR_ERR(fid);
1196			fid = NULL;
1197			goto error;
1198		}
1199
1200		fid->uid = oldfid->uid;
1201	} else
1202		fid = oldfid;
1203
1204
1205	p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1206		 oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1207
1208	req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1209								nwname, wnames);
1210	if (IS_ERR(req)) {
1211		err = PTR_ERR(req);
1212		goto error;
1213	}
1214
1215	err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1216	if (err) {
1217		trace_9p_protocol_dump(clnt, req->rc);
1218		p9_free_req(clnt, req);
1219		goto clunk_fid;
1220	}
1221	p9_free_req(clnt, req);
1222
1223	p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1224
1225	if (nwqids != nwname) {
1226		err = -ENOENT;
1227		goto clunk_fid;
1228	}
1229
1230	for (count = 0; count < nwqids; count++)
1231		p9_debug(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
1232			count, wqids[count].type,
1233			(unsigned long long)wqids[count].path,
1234			wqids[count].version);
1235
1236	if (nwname)
1237		memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1238	else
1239		fid->qid = oldfid->qid;
1240
1241	kfree(wqids);
1242	return fid;
1243
1244clunk_fid:
1245	kfree(wqids);
1246	p9_client_clunk(fid);
1247	fid = NULL;
1248
1249error:
1250	if (fid && (fid != oldfid))
1251		p9_fid_destroy(fid);
1252
1253	return ERR_PTR(err);
1254}
1255EXPORT_SYMBOL(p9_client_walk);
1256
1257int p9_client_open(struct p9_fid *fid, int mode)
1258{
1259	int err;
1260	struct p9_client *clnt;
1261	struct p9_req_t *req;
1262	struct p9_qid qid;
1263	int iounit;
1264
1265	clnt = fid->clnt;
1266	p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1267		p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1268	err = 0;
1269
1270	if (fid->mode != -1)
1271		return -EINVAL;
1272
1273	if (p9_is_proto_dotl(clnt))
1274		req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1275	else
1276		req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1277	if (IS_ERR(req)) {
1278		err = PTR_ERR(req);
1279		goto error;
1280	}
1281
1282	err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1283	if (err) {
1284		trace_9p_protocol_dump(clnt, req->rc);
1285		goto free_and_error;
1286	}
1287
1288	p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1289		p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1290		(unsigned long long)qid.path, qid.version, iounit);
1291
1292	fid->mode = mode;
1293	fid->iounit = iounit;
1294
1295free_and_error:
1296	p9_free_req(clnt, req);
1297error:
1298	return err;
1299}
1300EXPORT_SYMBOL(p9_client_open);
1301
1302int p9_client_create_dotl(struct p9_fid *ofid, const char *name, u32 flags, u32 mode,
1303		kgid_t gid, struct p9_qid *qid)
1304{
1305	int err = 0;
1306	struct p9_client *clnt;
1307	struct p9_req_t *req;
1308	int iounit;
1309
1310	p9_debug(P9_DEBUG_9P,
1311			">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1312			ofid->fid, name, flags, mode,
1313		 	from_kgid(&init_user_ns, gid));
1314	clnt = ofid->clnt;
1315
1316	if (ofid->mode != -1)
1317		return -EINVAL;
1318
1319	req = p9_client_rpc(clnt, P9_TLCREATE, "dsddg", ofid->fid, name, flags,
1320			mode, gid);
1321	if (IS_ERR(req)) {
1322		err = PTR_ERR(req);
1323		goto error;
1324	}
1325
1326	err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1327	if (err) {
1328		trace_9p_protocol_dump(clnt, req->rc);
1329		goto free_and_error;
1330	}
1331
1332	p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1333			qid->type,
1334			(unsigned long long)qid->path,
1335			qid->version, iounit);
1336
1337	ofid->mode = mode;
1338	ofid->iounit = iounit;
1339
1340free_and_error:
1341	p9_free_req(clnt, req);
1342error:
1343	return err;
1344}
1345EXPORT_SYMBOL(p9_client_create_dotl);
1346
1347int p9_client_fcreate(struct p9_fid *fid, const char *name, u32 perm, int mode,
1348		     char *extension)
1349{
1350	int err;
1351	struct p9_client *clnt;
1352	struct p9_req_t *req;
1353	struct p9_qid qid;
1354	int iounit;
1355
1356	p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1357						fid->fid, name, perm, mode);
1358	err = 0;
1359	clnt = fid->clnt;
1360
1361	if (fid->mode != -1)
1362		return -EINVAL;
1363
1364	req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1365				mode, extension);
1366	if (IS_ERR(req)) {
1367		err = PTR_ERR(req);
1368		goto error;
1369	}
1370
1371	err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1372	if (err) {
1373		trace_9p_protocol_dump(clnt, req->rc);
1374		goto free_and_error;
1375	}
1376
1377	p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1378				qid.type,
1379				(unsigned long long)qid.path,
1380				qid.version, iounit);
1381
1382	fid->mode = mode;
1383	fid->iounit = iounit;
1384
1385free_and_error:
1386	p9_free_req(clnt, req);
1387error:
1388	return err;
1389}
1390EXPORT_SYMBOL(p9_client_fcreate);
1391
1392int p9_client_symlink(struct p9_fid *dfid, const char *name,
1393		const char *symtgt, kgid_t gid, struct p9_qid *qid)
1394{
1395	int err = 0;
1396	struct p9_client *clnt;
1397	struct p9_req_t *req;
1398
1399	p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1400			dfid->fid, name, symtgt);
1401	clnt = dfid->clnt;
1402
1403	req = p9_client_rpc(clnt, P9_TSYMLINK, "dssg", dfid->fid, name, symtgt,
1404			gid);
1405	if (IS_ERR(req)) {
1406		err = PTR_ERR(req);
1407		goto error;
1408	}
1409
1410	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1411	if (err) {
1412		trace_9p_protocol_dump(clnt, req->rc);
1413		goto free_and_error;
1414	}
1415
1416	p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1417			qid->type, (unsigned long long)qid->path, qid->version);
1418
1419free_and_error:
1420	p9_free_req(clnt, req);
1421error:
1422	return err;
1423}
1424EXPORT_SYMBOL(p9_client_symlink);
1425
1426int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, const char *newname)
1427{
1428	struct p9_client *clnt;
1429	struct p9_req_t *req;
1430
1431	p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1432			dfid->fid, oldfid->fid, newname);
1433	clnt = dfid->clnt;
1434	req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1435			newname);
1436	if (IS_ERR(req))
1437		return PTR_ERR(req);
1438
1439	p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
1440	p9_free_req(clnt, req);
1441	return 0;
1442}
1443EXPORT_SYMBOL(p9_client_link);
1444
1445int p9_client_fsync(struct p9_fid *fid, int datasync)
1446{
1447	int err;
1448	struct p9_client *clnt;
1449	struct p9_req_t *req;
1450
1451	p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1452			fid->fid, datasync);
1453	err = 0;
1454	clnt = fid->clnt;
1455
1456	req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1457	if (IS_ERR(req)) {
1458		err = PTR_ERR(req);
1459		goto error;
1460	}
1461
1462	p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1463
1464	p9_free_req(clnt, req);
1465
1466error:
1467	return err;
1468}
1469EXPORT_SYMBOL(p9_client_fsync);
1470
1471int p9_client_clunk(struct p9_fid *fid)
1472{
1473	int err;
1474	struct p9_client *clnt;
1475	struct p9_req_t *req;
1476	int retries = 0;
1477
1478	if (!fid) {
1479		pr_warn("%s (%d): Trying to clunk with NULL fid\n",
1480			__func__, task_pid_nr(current));
1481		dump_stack();
1482		return 0;
1483	}
1484
1485again:
1486	p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n", fid->fid,
1487								retries);
1488	err = 0;
1489	clnt = fid->clnt;
1490
1491	req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1492	if (IS_ERR(req)) {
1493		err = PTR_ERR(req);
1494		goto error;
1495	}
1496
1497	p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1498
1499	p9_free_req(clnt, req);
1500error:
1501	/*
1502	 * Fid is not valid even after a failed clunk
1503	 * If interrupted, retry once then give up and
1504	 * leak fid until umount.
1505	 */
1506	if (err == -ERESTARTSYS) {
1507		if (retries++ == 0)
1508			goto again;
1509	} else
1510		p9_fid_destroy(fid);
1511	return err;
1512}
1513EXPORT_SYMBOL(p9_client_clunk);
1514
1515int p9_client_remove(struct p9_fid *fid)
1516{
1517	int err;
1518	struct p9_client *clnt;
1519	struct p9_req_t *req;
1520
1521	p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1522	err = 0;
1523	clnt = fid->clnt;
1524
1525	req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1526	if (IS_ERR(req)) {
1527		err = PTR_ERR(req);
1528		goto error;
1529	}
1530
1531	p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1532
1533	p9_free_req(clnt, req);
1534error:
1535	if (err == -ERESTARTSYS)
1536		p9_client_clunk(fid);
1537	else
1538		p9_fid_destroy(fid);
1539	return err;
1540}
1541EXPORT_SYMBOL(p9_client_remove);
1542
1543int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1544{
1545	int err = 0;
1546	struct p9_req_t *req;
1547	struct p9_client *clnt;
1548
1549	p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1550		   dfid->fid, name, flags);
1551
1552	clnt = dfid->clnt;
1553	req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1554	if (IS_ERR(req)) {
1555		err = PTR_ERR(req);
1556		goto error;
1557	}
1558	p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1559
1560	p9_free_req(clnt, req);
1561error:
1562	return err;
1563}
1564EXPORT_SYMBOL(p9_client_unlinkat);
1565
1566int
1567p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err)
1568{
1569	struct p9_client *clnt = fid->clnt;
1570	struct p9_req_t *req;
1571	int total = 0;
1572	*err = 0;
1573
1574	p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
1575		   fid->fid, (unsigned long long) offset, (int)iov_iter_count(to));
1576
1577	while (iov_iter_count(to)) {
1578		int count = iov_iter_count(to);
1579		int rsize, non_zc = 0;
1580		char *dataptr;
1581			
1582		rsize = fid->iounit;
1583		if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1584			rsize = clnt->msize - P9_IOHDRSZ;
1585
1586		if (count < rsize)
1587			rsize = count;
1588
1589		/* Don't bother zerocopy for small IO (< 1024) */
1590		if (clnt->trans_mod->zc_request && rsize > 1024) {
1591			/*
1592			 * response header len is 11
1593			 * PDU Header(7) + IO Size (4)
1594			 */
1595			req = p9_client_zc_rpc(clnt, P9_TREAD, to, NULL, rsize,
1596					       0, 11, "dqd", fid->fid,
1597					       offset, rsize);
1598		} else {
1599			non_zc = 1;
1600			req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1601					    rsize);
1602		}
1603		if (IS_ERR(req)) {
1604			*err = PTR_ERR(req);
1605			break;
1606		}
1607
1608		*err = p9pdu_readf(req->rc, clnt->proto_version,
1609				   "D", &count, &dataptr);
1610		if (*err) {
1611			trace_9p_protocol_dump(clnt, req->rc);
1612			p9_free_req(clnt, req);
1613			break;
1614		}
1615		if (rsize < count) {
1616			pr_err("bogus RREAD count (%d > %d)\n", count, rsize);
1617			count = rsize;
1618		}
1619
1620		p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1621		if (!count) {
1622			p9_free_req(clnt, req);
1623			break;
1624		}
1625
1626		if (non_zc) {
1627			int n = copy_to_iter(dataptr, count, to);
1628			total += n;
1629			offset += n;
1630			if (n != count) {
1631				*err = -EFAULT;
1632				p9_free_req(clnt, req);
1633				break;
1634			}
1635		} else {
1636			iov_iter_advance(to, count);
1637			total += count;
1638			offset += count;
1639		}
1640		p9_free_req(clnt, req);
1641	}
1642	return total;
1643}
1644EXPORT_SYMBOL(p9_client_read);
1645
1646int
1647p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err)
1648{
1649	struct p9_client *clnt = fid->clnt;
1650	struct p9_req_t *req;
1651	int total = 0;
1652	*err = 0;
1653
1654	p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %zd\n",
1655				fid->fid, (unsigned long long) offset,
1656				iov_iter_count(from));
1657
1658	while (iov_iter_count(from)) {
1659		int count = iov_iter_count(from);
1660		int rsize = fid->iounit;
1661		if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1662			rsize = clnt->msize - P9_IOHDRSZ;
1663
1664		if (count < rsize)
1665			rsize = count;
1666
1667		/* Don't bother zerocopy for small IO (< 1024) */
1668		if (clnt->trans_mod->zc_request && rsize > 1024) {
1669			req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, from, 0,
1670					       rsize, P9_ZC_HDR_SZ, "dqd",
1671					       fid->fid, offset, rsize);
1672		} else {
1673			req = p9_client_rpc(clnt, P9_TWRITE, "dqV", fid->fid,
1674						    offset, rsize, from);
1675		}
1676		if (IS_ERR(req)) {
1677			*err = PTR_ERR(req);
1678			break;
1679		}
1680
1681		*err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1682		if (*err) {
1683			trace_9p_protocol_dump(clnt, req->rc);
1684			p9_free_req(clnt, req);
1685			break;
1686		}
1687		if (rsize < count) {
1688			pr_err("bogus RWRITE count (%d > %d)\n", count, rsize);
1689			count = rsize;
1690		}
1691
1692		p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1693
1694		p9_free_req(clnt, req);
1695		iov_iter_advance(from, count);
1696		total += count;
1697		offset += count;
1698	}
1699	return total;
1700}
1701EXPORT_SYMBOL(p9_client_write);
1702
1703struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1704{
1705	int err;
1706	struct p9_client *clnt;
1707	struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1708	struct p9_req_t *req;
1709	u16 ignored;
1710
1711	p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1712
1713	if (!ret)
1714		return ERR_PTR(-ENOMEM);
1715
1716	err = 0;
1717	clnt = fid->clnt;
1718
1719	req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1720	if (IS_ERR(req)) {
1721		err = PTR_ERR(req);
1722		goto error;
1723	}
1724
1725	err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1726	if (err) {
1727		trace_9p_protocol_dump(clnt, req->rc);
1728		p9_free_req(clnt, req);
1729		goto error;
1730	}
1731
1732	p9_debug(P9_DEBUG_9P,
1733		"<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1734		"<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1735		"<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1736		"<<<    uid=%d gid=%d n_muid=%d\n",
1737		ret->size, ret->type, ret->dev, ret->qid.type,
1738		(unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1739		ret->atime, ret->mtime, (unsigned long long)ret->length,
1740		ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1741		from_kuid(&init_user_ns, ret->n_uid),
1742		from_kgid(&init_user_ns, ret->n_gid),
1743		from_kuid(&init_user_ns, ret->n_muid));
1744
1745	p9_free_req(clnt, req);
1746	return ret;
1747
1748error:
1749	kfree(ret);
1750	return ERR_PTR(err);
1751}
1752EXPORT_SYMBOL(p9_client_stat);
1753
1754struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1755							u64 request_mask)
1756{
1757	int err;
1758	struct p9_client *clnt;
1759	struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1760								GFP_KERNEL);
1761	struct p9_req_t *req;
1762
1763	p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1764							fid->fid, request_mask);
1765
1766	if (!ret)
1767		return ERR_PTR(-ENOMEM);
1768
1769	err = 0;
1770	clnt = fid->clnt;
1771
1772	req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1773	if (IS_ERR(req)) {
1774		err = PTR_ERR(req);
1775		goto error;
1776	}
1777
1778	err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1779	if (err) {
1780		trace_9p_protocol_dump(clnt, req->rc);
1781		p9_free_req(clnt, req);
1782		goto error;
1783	}
1784
1785	p9_debug(P9_DEBUG_9P,
1786		"<<< RGETATTR st_result_mask=%lld\n"
1787		"<<< qid=%x.%llx.%x\n"
1788		"<<< st_mode=%8.8x st_nlink=%llu\n"
1789		"<<< st_uid=%d st_gid=%d\n"
1790		"<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1791		"<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1792		"<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1793		"<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1794		"<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1795		"<<< st_gen=%lld st_data_version=%lld",
1796		ret->st_result_mask, ret->qid.type, ret->qid.path,
1797		ret->qid.version, ret->st_mode, ret->st_nlink,
1798		from_kuid(&init_user_ns, ret->st_uid),
1799		from_kgid(&init_user_ns, ret->st_gid),
1800		ret->st_rdev, ret->st_size, ret->st_blksize,
1801		ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1802		ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1803		ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1804		ret->st_gen, ret->st_data_version);
1805
1806	p9_free_req(clnt, req);
1807	return ret;
1808
1809error:
1810	kfree(ret);
1811	return ERR_PTR(err);
1812}
1813EXPORT_SYMBOL(p9_client_getattr_dotl);
1814
1815static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1816{
1817	int ret;
1818
1819	/* NOTE: size shouldn't include its own length */
1820	/* size[2] type[2] dev[4] qid[13] */
1821	/* mode[4] atime[4] mtime[4] length[8]*/
1822	/* name[s] uid[s] gid[s] muid[s] */
1823	ret = 2+4+13+4+4+4+8+2+2+2+2;
1824
1825	if (wst->name)
1826		ret += strlen(wst->name);
1827	if (wst->uid)
1828		ret += strlen(wst->uid);
1829	if (wst->gid)
1830		ret += strlen(wst->gid);
1831	if (wst->muid)
1832		ret += strlen(wst->muid);
1833
1834	if ((proto_version == p9_proto_2000u) ||
1835		(proto_version == p9_proto_2000L)) {
1836		ret += 2+4+4+4;	/* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1837		if (wst->extension)
1838			ret += strlen(wst->extension);
1839	}
1840
1841	return ret;
1842}
1843
1844int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1845{
1846	int err;
1847	struct p9_req_t *req;
1848	struct p9_client *clnt;
1849
1850	err = 0;
1851	clnt = fid->clnt;
1852	wst->size = p9_client_statsize(wst, clnt->proto_version);
1853	p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1854	p9_debug(P9_DEBUG_9P,
1855		"     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1856		"     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1857		"     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1858		"     uid=%d gid=%d n_muid=%d\n",
1859		wst->size, wst->type, wst->dev, wst->qid.type,
1860		(unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1861		wst->atime, wst->mtime, (unsigned long long)wst->length,
1862		wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1863		from_kuid(&init_user_ns, wst->n_uid),
1864		from_kgid(&init_user_ns, wst->n_gid),
1865		from_kuid(&init_user_ns, wst->n_muid));
1866
1867	req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1868	if (IS_ERR(req)) {
1869		err = PTR_ERR(req);
1870		goto error;
1871	}
1872
1873	p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1874
1875	p9_free_req(clnt, req);
1876error:
1877	return err;
1878}
1879EXPORT_SYMBOL(p9_client_wstat);
1880
1881int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1882{
1883	int err;
1884	struct p9_req_t *req;
1885	struct p9_client *clnt;
1886
1887	err = 0;
1888	clnt = fid->clnt;
1889	p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1890	p9_debug(P9_DEBUG_9P,
1891		"    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1892		"    atime_sec=%lld atime_nsec=%lld\n"
1893		"    mtime_sec=%lld mtime_nsec=%lld\n",
1894		p9attr->valid, p9attr->mode,
1895		from_kuid(&init_user_ns, p9attr->uid),
1896		from_kgid(&init_user_ns, p9attr->gid),
1897		p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1898		p9attr->mtime_sec, p9attr->mtime_nsec);
1899
1900	req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1901
1902	if (IS_ERR(req)) {
1903		err = PTR_ERR(req);
1904		goto error;
1905	}
1906	p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1907	p9_free_req(clnt, req);
1908error:
1909	return err;
1910}
1911EXPORT_SYMBOL(p9_client_setattr);
1912
1913int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1914{
1915	int err;
1916	struct p9_req_t *req;
1917	struct p9_client *clnt;
1918
1919	err = 0;
1920	clnt = fid->clnt;
1921
1922	p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1923
1924	req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1925	if (IS_ERR(req)) {
1926		err = PTR_ERR(req);
1927		goto error;
1928	}
1929
1930	err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1931		&sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1932		&sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1933	if (err) {
1934		trace_9p_protocol_dump(clnt, req->rc);
1935		p9_free_req(clnt, req);
1936		goto error;
1937	}
1938
1939	p9_debug(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1940		"blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1941		"fsid %llu namelen %ld\n",
1942		fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1943		sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1944		sb->fsid, (long int)sb->namelen);
1945
1946	p9_free_req(clnt, req);
1947error:
1948	return err;
1949}
1950EXPORT_SYMBOL(p9_client_statfs);
1951
1952int p9_client_rename(struct p9_fid *fid,
1953		     struct p9_fid *newdirfid, const char *name)
1954{
1955	int err;
1956	struct p9_req_t *req;
1957	struct p9_client *clnt;
1958
1959	err = 0;
1960	clnt = fid->clnt;
1961
1962	p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1963			fid->fid, newdirfid->fid, name);
1964
1965	req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1966			newdirfid->fid, name);
1967	if (IS_ERR(req)) {
1968		err = PTR_ERR(req);
1969		goto error;
1970	}
1971
1972	p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1973
1974	p9_free_req(clnt, req);
1975error:
1976	return err;
1977}
1978EXPORT_SYMBOL(p9_client_rename);
1979
1980int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1981		       struct p9_fid *newdirfid, const char *new_name)
1982{
1983	int err;
1984	struct p9_req_t *req;
1985	struct p9_client *clnt;
1986
1987	err = 0;
1988	clnt = olddirfid->clnt;
1989
1990	p9_debug(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1991		   " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1992		   newdirfid->fid, new_name);
1993
1994	req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1995			    old_name, newdirfid->fid, new_name);
1996	if (IS_ERR(req)) {
1997		err = PTR_ERR(req);
1998		goto error;
1999	}
2000
2001	p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
2002		   newdirfid->fid, new_name);
2003
2004	p9_free_req(clnt, req);
2005error:
2006	return err;
2007}
2008EXPORT_SYMBOL(p9_client_renameat);
2009
2010/*
2011 * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
2012 */
2013struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
2014				const char *attr_name, u64 *attr_size)
2015{
2016	int err;
2017	struct p9_req_t *req;
2018	struct p9_client *clnt;
2019	struct p9_fid *attr_fid;
2020
2021	err = 0;
2022	clnt = file_fid->clnt;
2023	attr_fid = p9_fid_create(clnt);
2024	if (IS_ERR(attr_fid)) {
2025		err = PTR_ERR(attr_fid);
2026		attr_fid = NULL;
2027		goto error;
2028	}
2029	p9_debug(P9_DEBUG_9P,
2030		">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
2031		file_fid->fid, attr_fid->fid, attr_name);
2032
2033	req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
2034			file_fid->fid, attr_fid->fid, attr_name);
2035	if (IS_ERR(req)) {
2036		err = PTR_ERR(req);
2037		goto error;
2038	}
2039	err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
2040	if (err) {
2041		trace_9p_protocol_dump(clnt, req->rc);
2042		p9_free_req(clnt, req);
2043		goto clunk_fid;
2044	}
2045	p9_free_req(clnt, req);
2046	p9_debug(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
2047		attr_fid->fid, *attr_size);
2048	return attr_fid;
2049clunk_fid:
2050	p9_client_clunk(attr_fid);
2051	attr_fid = NULL;
2052error:
2053	if (attr_fid && (attr_fid != file_fid))
2054		p9_fid_destroy(attr_fid);
2055
2056	return ERR_PTR(err);
2057}
2058EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
2059
2060int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
2061			u64 attr_size, int flags)
2062{
2063	int err;
2064	struct p9_req_t *req;
2065	struct p9_client *clnt;
2066
2067	p9_debug(P9_DEBUG_9P,
2068		">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
2069		fid->fid, name, (long long)attr_size, flags);
2070	err = 0;
2071	clnt = fid->clnt;
2072	req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2073			fid->fid, name, attr_size, flags);
2074	if (IS_ERR(req)) {
2075		err = PTR_ERR(req);
2076		goto error;
2077	}
2078	p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2079	p9_free_req(clnt, req);
2080error:
2081	return err;
2082}
2083EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2084
2085int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2086{
2087	int err, rsize, non_zc = 0;
2088	struct p9_client *clnt;
2089	struct p9_req_t *req;
2090	char *dataptr;
2091	struct kvec kv = {.iov_base = data, .iov_len = count};
2092	struct iov_iter to;
2093
2094	iov_iter_kvec(&to, READ | ITER_KVEC, &kv, 1, count);
2095
2096	p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2097				fid->fid, (unsigned long long) offset, count);
2098
2099	err = 0;
2100	clnt = fid->clnt;
2101
2102	rsize = fid->iounit;
2103	if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2104		rsize = clnt->msize - P9_READDIRHDRSZ;
2105
2106	if (count < rsize)
2107		rsize = count;
2108
2109	/* Don't bother zerocopy for small IO (< 1024) */
2110	if (clnt->trans_mod->zc_request && rsize > 1024) {
2111		/*
2112		 * response header len is 11
2113		 * PDU Header(7) + IO Size (4)
2114		 */
2115		req = p9_client_zc_rpc(clnt, P9_TREADDIR, &to, NULL, rsize, 0,
2116				       11, "dqd", fid->fid, offset, rsize);
2117	} else {
2118		non_zc = 1;
2119		req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2120				    offset, rsize);
2121	}
2122	if (IS_ERR(req)) {
2123		err = PTR_ERR(req);
2124		goto error;
2125	}
2126
2127	err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2128	if (err) {
2129		trace_9p_protocol_dump(clnt, req->rc);
2130		goto free_and_error;
2131	}
2132	if (rsize < count) {
2133		pr_err("bogus RREADDIR count (%d > %d)\n", count, rsize);
2134		count = rsize;
2135	}
2136
2137	p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2138
2139	if (non_zc)
2140		memmove(data, dataptr, count);
2141
2142	p9_free_req(clnt, req);
2143	return count;
2144
2145free_and_error:
2146	p9_free_req(clnt, req);
2147error:
2148	return err;
2149}
2150EXPORT_SYMBOL(p9_client_readdir);
2151
2152int p9_client_mknod_dotl(struct p9_fid *fid, const char *name, int mode,
2153			dev_t rdev, kgid_t gid, struct p9_qid *qid)
2154{
2155	int err;
2156	struct p9_client *clnt;
2157	struct p9_req_t *req;
2158
2159	err = 0;
2160	clnt = fid->clnt;
2161	p9_debug(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2162		"minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2163	req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddg", fid->fid, name, mode,
2164		MAJOR(rdev), MINOR(rdev), gid);
2165	if (IS_ERR(req))
2166		return PTR_ERR(req);
2167
2168	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2169	if (err) {
2170		trace_9p_protocol_dump(clnt, req->rc);
2171		goto error;
2172	}
2173	p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2174				(unsigned long long)qid->path, qid->version);
2175
2176error:
2177	p9_free_req(clnt, req);
2178	return err;
2179
2180}
2181EXPORT_SYMBOL(p9_client_mknod_dotl);
2182
2183int p9_client_mkdir_dotl(struct p9_fid *fid, const char *name, int mode,
2184				kgid_t gid, struct p9_qid *qid)
2185{
2186	int err;
2187	struct p9_client *clnt;
2188	struct p9_req_t *req;
2189
2190	err = 0;
2191	clnt = fid->clnt;
2192	p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2193		 fid->fid, name, mode, from_kgid(&init_user_ns, gid));
2194	req = p9_client_rpc(clnt, P9_TMKDIR, "dsdg", fid->fid, name, mode,
2195		gid);
2196	if (IS_ERR(req))
2197		return PTR_ERR(req);
2198
2199	err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2200	if (err) {
2201		trace_9p_protocol_dump(clnt, req->rc);
2202		goto error;
2203	}
2204	p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2205				(unsigned long long)qid->path, qid->version);
2206
2207error:
2208	p9_free_req(clnt, req);
2209	return err;
2210
2211}
2212EXPORT_SYMBOL(p9_client_mkdir_dotl);
2213
2214int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2215{
2216	int err;
2217	struct p9_client *clnt;
2218	struct p9_req_t *req;
2219
2220	err = 0;
2221	clnt = fid->clnt;
2222	p9_debug(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2223			"start %lld length %lld proc_id %d client_id %s\n",
2224			fid->fid, flock->type, flock->flags, flock->start,
2225			flock->length, flock->proc_id, flock->client_id);
2226
2227	req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2228				flock->flags, flock->start, flock->length,
2229					flock->proc_id, flock->client_id);
2230
2231	if (IS_ERR(req))
2232		return PTR_ERR(req);
2233
2234	err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2235	if (err) {
2236		trace_9p_protocol_dump(clnt, req->rc);
2237		goto error;
2238	}
2239	p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2240error:
2241	p9_free_req(clnt, req);
2242	return err;
2243
2244}
2245EXPORT_SYMBOL(p9_client_lock_dotl);
2246
2247int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2248{
2249	int err;
2250	struct p9_client *clnt;
2251	struct p9_req_t *req;
2252
2253	err = 0;
2254	clnt = fid->clnt;
2255	p9_debug(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
2256		"length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2257		glock->start, glock->length, glock->proc_id, glock->client_id);
2258
2259	req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
2260		glock->start, glock->length, glock->proc_id, glock->client_id);
2261
2262	if (IS_ERR(req))
2263		return PTR_ERR(req);
2264
2265	err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2266			&glock->start, &glock->length, &glock->proc_id,
2267			&glock->client_id);
2268	if (err) {
2269		trace_9p_protocol_dump(clnt, req->rc);
2270		goto error;
2271	}
2272	p9_debug(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2273		"proc_id %d client_id %s\n", glock->type, glock->start,
2274		glock->length, glock->proc_id, glock->client_id);
2275error:
2276	p9_free_req(clnt, req);
2277	return err;
2278}
2279EXPORT_SYMBOL(p9_client_getlock_dotl);
2280
2281int p9_client_readlink(struct p9_fid *fid, char **target)
2282{
2283	int err;
2284	struct p9_client *clnt;
2285	struct p9_req_t *req;
2286
2287	err = 0;
2288	clnt = fid->clnt;
2289	p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2290
2291	req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2292	if (IS_ERR(req))
2293		return PTR_ERR(req);
2294
2295	err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2296	if (err) {
2297		trace_9p_protocol_dump(clnt, req->rc);
2298		goto error;
2299	}
2300	p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2301error:
2302	p9_free_req(clnt, req);
2303	return err;
2304}
2305EXPORT_SYMBOL(p9_client_readlink);