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