linux/net/9p/client.c
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   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 <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) && ecode < 512)
 522                        err = -ecode;
 523
 524                if (!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) && ecode < 512)
 609                        err = -ecode;
 610
 611                if (!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        const char *uname, kuid_t n_uname, const 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                const unsigned char * const *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, const 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, const 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, const char *name,
1365                const char *symtgt, kgid_t gid, 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, const 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                if (rsize < count) {
1588                        pr_err("bogus RREAD count (%d > %d)\n", count, rsize);
1589                        count = rsize;
1590                }
1591
1592                p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1593                if (!count) {
1594                        p9_free_req(clnt, req);
1595                        break;
1596                }
1597
1598                if (non_zc) {
1599                        int n = copy_to_iter(dataptr, count, to);
1600                        total += n;
1601                        offset += n;
1602                        if (n != count) {
1603                                *err = -EFAULT;
1604                                p9_free_req(clnt, req);
1605                                break;
1606                        }
1607                } else {
1608                        iov_iter_advance(to, count);
1609                        total += count;
1610                        offset += count;
1611                }
1612                p9_free_req(clnt, req);
1613        }
1614        return total;
1615}
1616EXPORT_SYMBOL(p9_client_read);
1617
1618int
1619p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err)
1620{
1621        struct p9_client *clnt = fid->clnt;
1622        struct p9_req_t *req;
1623        int total = 0;
1624        *err = 0;
1625
1626        p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %zd\n",
1627                                fid->fid, (unsigned long long) offset,
1628                                iov_iter_count(from));
1629
1630        while (iov_iter_count(from)) {
1631                int count = iov_iter_count(from);
1632                int rsize = fid->iounit;
1633                if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1634                        rsize = clnt->msize - P9_IOHDRSZ;
1635
1636                if (count < rsize)
1637                        rsize = count;
1638
1639                /* Don't bother zerocopy for small IO (< 1024) */
1640                if (clnt->trans_mod->zc_request && rsize > 1024) {
1641                        req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, from, 0,
1642                                               rsize, P9_ZC_HDR_SZ, "dqd",
1643                                               fid->fid, offset, rsize);
1644                } else {
1645                        req = p9_client_rpc(clnt, P9_TWRITE, "dqV", fid->fid,
1646                                                    offset, rsize, from);
1647                }
1648                if (IS_ERR(req)) {
1649                        *err = PTR_ERR(req);
1650                        break;
1651                }
1652
1653                *err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1654                if (*err) {
1655                        trace_9p_protocol_dump(clnt, req->rc);
1656                        p9_free_req(clnt, req);
1657                        break;
1658                }
1659                if (rsize < count) {
1660                        pr_err("bogus RWRITE count (%d > %d)\n", count, rsize);
1661                        count = rsize;
1662                }
1663
1664                p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1665
1666                p9_free_req(clnt, req);
1667                iov_iter_advance(from, count);
1668                total += count;
1669                offset += count;
1670        }
1671        return total;
1672}
1673EXPORT_SYMBOL(p9_client_write);
1674
1675struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1676{
1677        int err;
1678        struct p9_client *clnt;
1679        struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1680        struct p9_req_t *req;
1681        u16 ignored;
1682
1683        p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1684
1685        if (!ret)
1686                return ERR_PTR(-ENOMEM);
1687
1688        err = 0;
1689        clnt = fid->clnt;
1690
1691        req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1692        if (IS_ERR(req)) {
1693                err = PTR_ERR(req);
1694                goto error;
1695        }
1696
1697        err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1698        if (err) {
1699                trace_9p_protocol_dump(clnt, req->rc);
1700                p9_free_req(clnt, req);
1701                goto error;
1702        }
1703
1704        p9_debug(P9_DEBUG_9P,
1705                "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1706                "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1707                "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1708                "<<<    uid=%d gid=%d n_muid=%d\n",
1709                ret->size, ret->type, ret->dev, ret->qid.type,
1710                (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1711                ret->atime, ret->mtime, (unsigned long long)ret->length,
1712                ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1713                from_kuid(&init_user_ns, ret->n_uid),
1714                from_kgid(&init_user_ns, ret->n_gid),
1715                from_kuid(&init_user_ns, ret->n_muid));
1716
1717        p9_free_req(clnt, req);
1718        return ret;
1719
1720error:
1721        kfree(ret);
1722        return ERR_PTR(err);
1723}
1724EXPORT_SYMBOL(p9_client_stat);
1725
1726struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1727                                                        u64 request_mask)
1728{
1729        int err;
1730        struct p9_client *clnt;
1731        struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1732                                                                GFP_KERNEL);
1733        struct p9_req_t *req;
1734
1735        p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1736                                                        fid->fid, request_mask);
1737
1738        if (!ret)
1739                return ERR_PTR(-ENOMEM);
1740
1741        err = 0;
1742        clnt = fid->clnt;
1743
1744        req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1745        if (IS_ERR(req)) {
1746                err = PTR_ERR(req);
1747                goto error;
1748        }
1749
1750        err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1751        if (err) {
1752                trace_9p_protocol_dump(clnt, req->rc);
1753                p9_free_req(clnt, req);
1754                goto error;
1755        }
1756
1757        p9_debug(P9_DEBUG_9P,
1758                "<<< RGETATTR st_result_mask=%lld\n"
1759                "<<< qid=%x.%llx.%x\n"
1760                "<<< st_mode=%8.8x st_nlink=%llu\n"
1761                "<<< st_uid=%d st_gid=%d\n"
1762                "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1763                "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1764                "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1765                "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1766                "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1767                "<<< st_gen=%lld st_data_version=%lld",
1768                ret->st_result_mask, ret->qid.type, ret->qid.path,
1769                ret->qid.version, ret->st_mode, ret->st_nlink,
1770                from_kuid(&init_user_ns, ret->st_uid),
1771                from_kgid(&init_user_ns, ret->st_gid),
1772                ret->st_rdev, ret->st_size, ret->st_blksize,
1773                ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1774                ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1775                ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1776                ret->st_gen, ret->st_data_version);
1777
1778        p9_free_req(clnt, req);
1779        return ret;
1780
1781error:
1782        kfree(ret);
1783        return ERR_PTR(err);
1784}
1785EXPORT_SYMBOL(p9_client_getattr_dotl);
1786
1787static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1788{
1789        int ret;
1790
1791        /* NOTE: size shouldn't include its own length */
1792        /* size[2] type[2] dev[4] qid[13] */
1793        /* mode[4] atime[4] mtime[4] length[8]*/
1794        /* name[s] uid[s] gid[s] muid[s] */
1795        ret = 2+4+13+4+4+4+8+2+2+2+2;
1796
1797        if (wst->name)
1798                ret += strlen(wst->name);
1799        if (wst->uid)
1800                ret += strlen(wst->uid);
1801        if (wst->gid)
1802                ret += strlen(wst->gid);
1803        if (wst->muid)
1804                ret += strlen(wst->muid);
1805
1806        if ((proto_version == p9_proto_2000u) ||
1807                (proto_version == p9_proto_2000L)) {
1808                ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1809                if (wst->extension)
1810                        ret += strlen(wst->extension);
1811        }
1812
1813        return ret;
1814}
1815
1816int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1817{
1818        int err;
1819        struct p9_req_t *req;
1820        struct p9_client *clnt;
1821
1822        err = 0;
1823        clnt = fid->clnt;
1824        wst->size = p9_client_statsize(wst, clnt->proto_version);
1825        p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1826        p9_debug(P9_DEBUG_9P,
1827                "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1828                "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1829                "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1830                "     uid=%d gid=%d n_muid=%d\n",
1831                wst->size, wst->type, wst->dev, wst->qid.type,
1832                (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1833                wst->atime, wst->mtime, (unsigned long long)wst->length,
1834                wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1835                from_kuid(&init_user_ns, wst->n_uid),
1836                from_kgid(&init_user_ns, wst->n_gid),
1837                from_kuid(&init_user_ns, wst->n_muid));
1838
1839        req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1840        if (IS_ERR(req)) {
1841                err = PTR_ERR(req);
1842                goto error;
1843        }
1844
1845        p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1846
1847        p9_free_req(clnt, req);
1848error:
1849        return err;
1850}
1851EXPORT_SYMBOL(p9_client_wstat);
1852
1853int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1854{
1855        int err;
1856        struct p9_req_t *req;
1857        struct p9_client *clnt;
1858
1859        err = 0;
1860        clnt = fid->clnt;
1861        p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1862        p9_debug(P9_DEBUG_9P,
1863                "    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1864                "    atime_sec=%lld atime_nsec=%lld\n"
1865                "    mtime_sec=%lld mtime_nsec=%lld\n",
1866                p9attr->valid, p9attr->mode,
1867                from_kuid(&init_user_ns, p9attr->uid),
1868                from_kgid(&init_user_ns, p9attr->gid),
1869                p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1870                p9attr->mtime_sec, p9attr->mtime_nsec);
1871
1872        req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1873
1874        if (IS_ERR(req)) {
1875                err = PTR_ERR(req);
1876                goto error;
1877        }
1878        p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1879        p9_free_req(clnt, req);
1880error:
1881        return err;
1882}
1883EXPORT_SYMBOL(p9_client_setattr);
1884
1885int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1886{
1887        int err;
1888        struct p9_req_t *req;
1889        struct p9_client *clnt;
1890
1891        err = 0;
1892        clnt = fid->clnt;
1893
1894        p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1895
1896        req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1897        if (IS_ERR(req)) {
1898                err = PTR_ERR(req);
1899                goto error;
1900        }
1901
1902        err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1903                &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1904                &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1905        if (err) {
1906                trace_9p_protocol_dump(clnt, req->rc);
1907                p9_free_req(clnt, req);
1908                goto error;
1909        }
1910
1911        p9_debug(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1912                "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1913                "fsid %llu namelen %ld\n",
1914                fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1915                sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1916                sb->fsid, (long int)sb->namelen);
1917
1918        p9_free_req(clnt, req);
1919error:
1920        return err;
1921}
1922EXPORT_SYMBOL(p9_client_statfs);
1923
1924int p9_client_rename(struct p9_fid *fid,
1925                     struct p9_fid *newdirfid, const char *name)
1926{
1927        int err;
1928        struct p9_req_t *req;
1929        struct p9_client *clnt;
1930
1931        err = 0;
1932        clnt = fid->clnt;
1933
1934        p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1935                        fid->fid, newdirfid->fid, name);
1936
1937        req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1938                        newdirfid->fid, name);
1939        if (IS_ERR(req)) {
1940                err = PTR_ERR(req);
1941                goto error;
1942        }
1943
1944        p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1945
1946        p9_free_req(clnt, req);
1947error:
1948        return err;
1949}
1950EXPORT_SYMBOL(p9_client_rename);
1951
1952int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1953                       struct p9_fid *newdirfid, const char *new_name)
1954{
1955        int err;
1956        struct p9_req_t *req;
1957        struct p9_client *clnt;
1958
1959        err = 0;
1960        clnt = olddirfid->clnt;
1961
1962        p9_debug(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1963                   " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1964                   newdirfid->fid, new_name);
1965
1966        req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1967                            old_name, newdirfid->fid, new_name);
1968        if (IS_ERR(req)) {
1969                err = PTR_ERR(req);
1970                goto error;
1971        }
1972
1973        p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
1974                   newdirfid->fid, new_name);
1975
1976        p9_free_req(clnt, req);
1977error:
1978        return err;
1979}
1980EXPORT_SYMBOL(p9_client_renameat);
1981
1982/*
1983 * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1984 */
1985struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1986                                const char *attr_name, u64 *attr_size)
1987{
1988        int err;
1989        struct p9_req_t *req;
1990        struct p9_client *clnt;
1991        struct p9_fid *attr_fid;
1992
1993        err = 0;
1994        clnt = file_fid->clnt;
1995        attr_fid = p9_fid_create(clnt);
1996        if (IS_ERR(attr_fid)) {
1997                err = PTR_ERR(attr_fid);
1998                attr_fid = NULL;
1999                goto error;
2000        }
2001        p9_debug(P9_DEBUG_9P,
2002                ">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
2003                file_fid->fid, attr_fid->fid, attr_name);
2004
2005        req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
2006                        file_fid->fid, attr_fid->fid, attr_name);
2007        if (IS_ERR(req)) {
2008                err = PTR_ERR(req);
2009                goto error;
2010        }
2011        err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
2012        if (err) {
2013                trace_9p_protocol_dump(clnt, req->rc);
2014                p9_free_req(clnt, req);
2015                goto clunk_fid;
2016        }
2017        p9_free_req(clnt, req);
2018        p9_debug(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
2019                attr_fid->fid, *attr_size);
2020        return attr_fid;
2021clunk_fid:
2022        p9_client_clunk(attr_fid);
2023        attr_fid = NULL;
2024error:
2025        if (attr_fid && (attr_fid != file_fid))
2026                p9_fid_destroy(attr_fid);
2027
2028        return ERR_PTR(err);
2029}
2030EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
2031
2032int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
2033                        u64 attr_size, int flags)
2034{
2035        int err;
2036        struct p9_req_t *req;
2037        struct p9_client *clnt;
2038
2039        p9_debug(P9_DEBUG_9P,
2040                ">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
2041                fid->fid, name, (long long)attr_size, flags);
2042        err = 0;
2043        clnt = fid->clnt;
2044        req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2045                        fid->fid, name, attr_size, flags);
2046        if (IS_ERR(req)) {
2047                err = PTR_ERR(req);
2048                goto error;
2049        }
2050        p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2051        p9_free_req(clnt, req);
2052error:
2053        return err;
2054}
2055EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2056
2057int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2058{
2059        int err, rsize, non_zc = 0;
2060        struct p9_client *clnt;
2061        struct p9_req_t *req;
2062        char *dataptr;
2063        struct kvec kv = {.iov_base = data, .iov_len = count};
2064        struct iov_iter to;
2065
2066        iov_iter_kvec(&to, READ | ITER_KVEC, &kv, 1, count);
2067
2068        p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2069                                fid->fid, (unsigned long long) offset, count);
2070
2071        err = 0;
2072        clnt = fid->clnt;
2073
2074        rsize = fid->iounit;
2075        if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2076                rsize = clnt->msize - P9_READDIRHDRSZ;
2077
2078        if (count < rsize)
2079                rsize = count;
2080
2081        /* Don't bother zerocopy for small IO (< 1024) */
2082        if (clnt->trans_mod->zc_request && rsize > 1024) {
2083                /*
2084                 * response header len is 11
2085                 * PDU Header(7) + IO Size (4)
2086                 */
2087                req = p9_client_zc_rpc(clnt, P9_TREADDIR, &to, NULL, rsize, 0,
2088                                       11, "dqd", fid->fid, offset, rsize);
2089        } else {
2090                non_zc = 1;
2091                req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2092                                    offset, rsize);
2093        }
2094        if (IS_ERR(req)) {
2095                err = PTR_ERR(req);
2096                goto error;
2097        }
2098
2099        err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2100        if (err) {
2101                trace_9p_protocol_dump(clnt, req->rc);
2102                goto free_and_error;
2103        }
2104        if (rsize < count) {
2105                pr_err("bogus RREADDIR count (%d > %d)\n", count, rsize);
2106                count = rsize;
2107        }
2108
2109        p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2110
2111        if (non_zc)
2112                memmove(data, dataptr, count);
2113
2114        p9_free_req(clnt, req);
2115        return count;
2116
2117free_and_error:
2118        p9_free_req(clnt, req);
2119error:
2120        return err;
2121}
2122EXPORT_SYMBOL(p9_client_readdir);
2123
2124int p9_client_mknod_dotl(struct p9_fid *fid, const char *name, int mode,
2125                        dev_t rdev, kgid_t gid, struct p9_qid *qid)
2126{
2127        int err;
2128        struct p9_client *clnt;
2129        struct p9_req_t *req;
2130
2131        err = 0;
2132        clnt = fid->clnt;
2133        p9_debug(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2134                "minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2135        req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddg", fid->fid, name, mode,
2136                MAJOR(rdev), MINOR(rdev), gid);
2137        if (IS_ERR(req))
2138                return PTR_ERR(req);
2139
2140        err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2141        if (err) {
2142                trace_9p_protocol_dump(clnt, req->rc);
2143                goto error;
2144        }
2145        p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2146                                (unsigned long long)qid->path, qid->version);
2147
2148error:
2149        p9_free_req(clnt, req);
2150        return err;
2151
2152}
2153EXPORT_SYMBOL(p9_client_mknod_dotl);
2154
2155int p9_client_mkdir_dotl(struct p9_fid *fid, const char *name, int mode,
2156                                kgid_t gid, struct p9_qid *qid)
2157{
2158        int err;
2159        struct p9_client *clnt;
2160        struct p9_req_t *req;
2161
2162        err = 0;
2163        clnt = fid->clnt;
2164        p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2165                 fid->fid, name, mode, from_kgid(&init_user_ns, gid));
2166        req = p9_client_rpc(clnt, P9_TMKDIR, "dsdg", fid->fid, name, mode,
2167                gid);
2168        if (IS_ERR(req))
2169                return PTR_ERR(req);
2170
2171        err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2172        if (err) {
2173                trace_9p_protocol_dump(clnt, req->rc);
2174                goto error;
2175        }
2176        p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2177                                (unsigned long long)qid->path, qid->version);
2178
2179error:
2180        p9_free_req(clnt, req);
2181        return err;
2182
2183}
2184EXPORT_SYMBOL(p9_client_mkdir_dotl);
2185
2186int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2187{
2188        int err;
2189        struct p9_client *clnt;
2190        struct p9_req_t *req;
2191
2192        err = 0;
2193        clnt = fid->clnt;
2194        p9_debug(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2195                        "start %lld length %lld proc_id %d client_id %s\n",
2196                        fid->fid, flock->type, flock->flags, flock->start,
2197                        flock->length, flock->proc_id, flock->client_id);
2198
2199        req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2200                                flock->flags, flock->start, flock->length,
2201                                        flock->proc_id, flock->client_id);
2202
2203        if (IS_ERR(req))
2204                return PTR_ERR(req);
2205
2206        err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2207        if (err) {
2208                trace_9p_protocol_dump(clnt, req->rc);
2209                goto error;
2210        }
2211        p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2212error:
2213        p9_free_req(clnt, req);
2214        return err;
2215
2216}
2217EXPORT_SYMBOL(p9_client_lock_dotl);
2218
2219int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2220{
2221        int err;
2222        struct p9_client *clnt;
2223        struct p9_req_t *req;
2224
2225        err = 0;
2226        clnt = fid->clnt;
2227        p9_debug(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
2228                "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2229                glock->start, glock->length, glock->proc_id, glock->client_id);
2230
2231        req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
2232                glock->start, glock->length, glock->proc_id, glock->client_id);
2233
2234        if (IS_ERR(req))
2235                return PTR_ERR(req);
2236
2237        err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2238                        &glock->start, &glock->length, &glock->proc_id,
2239                        &glock->client_id);
2240        if (err) {
2241                trace_9p_protocol_dump(clnt, req->rc);
2242                goto error;
2243        }
2244        p9_debug(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2245                "proc_id %d client_id %s\n", glock->type, glock->start,
2246                glock->length, glock->proc_id, glock->client_id);
2247error:
2248        p9_free_req(clnt, req);
2249        return err;
2250}
2251EXPORT_SYMBOL(p9_client_getlock_dotl);
2252
2253int p9_client_readlink(struct p9_fid *fid, char **target)
2254{
2255        int err;
2256        struct p9_client *clnt;
2257        struct p9_req_t *req;
2258
2259        err = 0;
2260        clnt = fid->clnt;
2261        p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2262
2263        req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2264        if (IS_ERR(req))
2265                return PTR_ERR(req);
2266
2267        err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2268        if (err) {
2269                trace_9p_protocol_dump(clnt, req->rc);
2270                goto error;
2271        }
2272        p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2273error:
2274        p9_free_req(clnt, req);
2275        return err;
2276}
2277EXPORT_SYMBOL(p9_client_readlink);
2278