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#include <linux/module.h>
  27#include <linux/errno.h>
  28#include <linux/fs.h>
  29#include <linux/poll.h>
  30#include <linux/idr.h>
  31#include <linux/mutex.h>
  32#include <linux/slab.h>
  33#include <linux/sched.h>
  34#include <linux/uaccess.h>
  35#include <net/9p/9p.h>
  36#include <linux/parser.h>
  37#include <net/9p/client.h>
  38#include <net/9p/transport.h>
  39#include "protocol.h"
  40
  41/*
  42  * Client Option Parsing (code inspired by NFS code)
  43  *  - a little lazy - parse all client options
  44  */
  45
  46enum {
  47        Opt_msize,
  48        Opt_trans,
  49        Opt_legacy,
  50        Opt_version,
  51        Opt_err,
  52};
  53
  54static const match_table_t tokens = {
  55        {Opt_msize, "msize=%u"},
  56        {Opt_legacy, "noextend"},
  57        {Opt_trans, "trans=%s"},
  58        {Opt_version, "version=%s"},
  59        {Opt_err, NULL},
  60};
  61
  62inline int p9_is_proto_dotl(struct p9_client *clnt)
  63{
  64        return clnt->proto_version == p9_proto_2000L;
  65}
  66EXPORT_SYMBOL(p9_is_proto_dotl);
  67
  68inline int p9_is_proto_dotu(struct p9_client *clnt)
  69{
  70        return clnt->proto_version == p9_proto_2000u;
  71}
  72EXPORT_SYMBOL(p9_is_proto_dotu);
  73
  74/* Interpret mount option for protocol version */
  75static int get_protocol_version(char *s)
  76{
  77        int version = -EINVAL;
  78
  79        if (!strcmp(s, "9p2000")) {
  80                version = p9_proto_legacy;
  81                P9_DPRINTK(P9_DEBUG_9P, "Protocol version: Legacy\n");
  82        } else if (!strcmp(s, "9p2000.u")) {
  83                version = p9_proto_2000u;
  84                P9_DPRINTK(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
  85        } else if (!strcmp(s, "9p2000.L")) {
  86                version = p9_proto_2000L;
  87                P9_DPRINTK(P9_DEBUG_9P, "Protocol version: 9P2000.L\n");
  88        } else
  89                printk(KERN_INFO "9p: Unknown protocol version %s.\n", s);
  90
  91        return version;
  92}
  93
  94/**
  95 * parse_options - parse mount options into client structure
  96 * @opts: options string passed from mount
  97 * @clnt: existing v9fs client information
  98 *
  99 * Return 0 upon success, -ERRNO upon failure
 100 */
 101
 102static int parse_opts(char *opts, struct p9_client *clnt)
 103{
 104        char *options, *tmp_options;
 105        char *p;
 106        substring_t args[MAX_OPT_ARGS];
 107        int option;
 108        char *s;
 109        int ret = 0;
 110
 111        clnt->proto_version = p9_proto_2000u;
 112        clnt->msize = 8192;
 113
 114        if (!opts)
 115                return 0;
 116
 117        tmp_options = kstrdup(opts, GFP_KERNEL);
 118        if (!tmp_options) {
 119                P9_DPRINTK(P9_DEBUG_ERROR,
 120                                "failed to allocate copy of option string\n");
 121                return -ENOMEM;
 122        }
 123        options = tmp_options;
 124
 125        while ((p = strsep(&options, ",")) != NULL) {
 126                int token;
 127                if (!*p)
 128                        continue;
 129                token = match_token(p, tokens, args);
 130                if (token < Opt_trans) {
 131                        int r = match_int(&args[0], &option);
 132                        if (r < 0) {
 133                                P9_DPRINTK(P9_DEBUG_ERROR,
 134                                        "integer field, but no integer?\n");
 135                                ret = r;
 136                                continue;
 137                        }
 138                }
 139                switch (token) {
 140                case Opt_msize:
 141                        clnt->msize = option;
 142                        break;
 143                case Opt_trans:
 144                        s = match_strdup(&args[0]);
 145                        if (!s) {
 146                                ret = -ENOMEM;
 147                                P9_DPRINTK(P9_DEBUG_ERROR,
 148                                        "problem allocating copy of trans arg\n");
 149                                goto free_and_return;
 150                         }
 151                        clnt->trans_mod = v9fs_get_trans_by_name(s);
 152                        if (clnt->trans_mod == NULL) {
 153                                printk(KERN_INFO
 154                                        "9p: Could not find "
 155                                        "request transport: %s\n", s);
 156                                ret = -EINVAL;
 157                                kfree(s);
 158                                goto free_and_return;
 159                        }
 160                        kfree(s);
 161                        break;
 162                case Opt_legacy:
 163                        clnt->proto_version = p9_proto_legacy;
 164                        break;
 165                case Opt_version:
 166                        s = match_strdup(&args[0]);
 167                        if (!s) {
 168                                ret = -ENOMEM;
 169                                P9_DPRINTK(P9_DEBUG_ERROR,
 170                                        "problem allocating copy of version arg\n");
 171                                goto free_and_return;
 172                        }
 173                        ret = get_protocol_version(s);
 174                        if (ret == -EINVAL) {
 175                                kfree(s);
 176                                goto free_and_return;
 177                        }
 178                        kfree(s);
 179                        clnt->proto_version = ret;
 180                        break;
 181                default:
 182                        continue;
 183                }
 184        }
 185
 186free_and_return:
 187        kfree(tmp_options);
 188        return ret;
 189}
 190
 191/**
 192 * p9_tag_alloc - lookup/allocate a request by tag
 193 * @c: client session to lookup tag within
 194 * @tag: numeric id for transaction
 195 *
 196 * this is a simple array lookup, but will grow the
 197 * request_slots as necessary to accommodate transaction
 198 * ids which did not previously have a slot.
 199 *
 200 * this code relies on the client spinlock to manage locks, its
 201 * possible we should switch to something else, but I'd rather
 202 * stick with something low-overhead for the common case.
 203 *
 204 */
 205
 206static struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag)
 207{
 208        unsigned long flags;
 209        int row, col;
 210        struct p9_req_t *req;
 211
 212        /* This looks up the original request by tag so we know which
 213         * buffer to read the data into */
 214        tag++;
 215
 216        if (tag >= c->max_tag) {
 217                spin_lock_irqsave(&c->lock, flags);
 218                /* check again since original check was outside of lock */
 219                while (tag >= c->max_tag) {
 220                        row = (tag / P9_ROW_MAXTAG);
 221                        c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
 222                                        sizeof(struct p9_req_t), GFP_ATOMIC);
 223
 224                        if (!c->reqs[row]) {
 225                                printk(KERN_ERR "Couldn't grow tag array\n");
 226                                spin_unlock_irqrestore(&c->lock, flags);
 227                                return ERR_PTR(-ENOMEM);
 228                        }
 229                        for (col = 0; col < P9_ROW_MAXTAG; col++) {
 230                                c->reqs[row][col].status = REQ_STATUS_IDLE;
 231                                c->reqs[row][col].tc = NULL;
 232                        }
 233                        c->max_tag += P9_ROW_MAXTAG;
 234                }
 235                spin_unlock_irqrestore(&c->lock, flags);
 236        }
 237        row = tag / P9_ROW_MAXTAG;
 238        col = tag % P9_ROW_MAXTAG;
 239
 240        req = &c->reqs[row][col];
 241        if (!req->tc) {
 242                req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_NOFS);
 243                if (!req->wq) {
 244                        printk(KERN_ERR "Couldn't grow tag array\n");
 245                        return ERR_PTR(-ENOMEM);
 246                }
 247                init_waitqueue_head(req->wq);
 248                if ((c->trans_mod->pref & P9_TRANS_PREF_PAYLOAD_MASK) ==
 249                                P9_TRANS_PREF_PAYLOAD_SEP) {
 250                        int alloc_msize = min(c->msize, 4096);
 251                        req->tc = kmalloc(sizeof(struct p9_fcall)+alloc_msize,
 252                                          GFP_NOFS);
 253                        req->tc->capacity = alloc_msize;
 254                        req->rc = kmalloc(sizeof(struct p9_fcall)+alloc_msize,
 255                                          GFP_NOFS);
 256                        req->rc->capacity = alloc_msize;
 257                } else {
 258                        req->tc = kmalloc(sizeof(struct p9_fcall)+c->msize,
 259                                          GFP_NOFS);
 260                        req->tc->capacity = c->msize;
 261                        req->rc = kmalloc(sizeof(struct p9_fcall)+c->msize,
 262                                          GFP_NOFS);
 263                        req->rc->capacity = c->msize;
 264                }
 265                if ((!req->tc) || (!req->rc)) {
 266                        printk(KERN_ERR "Couldn't grow tag array\n");
 267                        kfree(req->tc);
 268                        kfree(req->rc);
 269                        kfree(req->wq);
 270                        req->tc = req->rc = NULL;
 271                        req->wq = NULL;
 272                        return ERR_PTR(-ENOMEM);
 273                }
 274                req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
 275                req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall);
 276        }
 277
 278        p9pdu_reset(req->tc);
 279        p9pdu_reset(req->rc);
 280
 281        req->tc->tag = tag-1;
 282        req->status = REQ_STATUS_ALLOC;
 283
 284        return &c->reqs[row][col];
 285}
 286
 287/**
 288 * p9_tag_lookup - lookup a request by tag
 289 * @c: client session to lookup tag within
 290 * @tag: numeric id for transaction
 291 *
 292 */
 293
 294struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
 295{
 296        int row, col;
 297
 298        /* This looks up the original request by tag so we know which
 299         * buffer to read the data into */
 300        tag++;
 301
 302        if(tag >= c->max_tag) 
 303                return NULL;
 304
 305        row = tag / P9_ROW_MAXTAG;
 306        col = tag % P9_ROW_MAXTAG;
 307
 308        return &c->reqs[row][col];
 309}
 310EXPORT_SYMBOL(p9_tag_lookup);
 311
 312/**
 313 * p9_tag_init - setup tags structure and contents
 314 * @c:  v9fs client struct
 315 *
 316 * This initializes the tags structure for each client instance.
 317 *
 318 */
 319
 320static int p9_tag_init(struct p9_client *c)
 321{
 322        int err = 0;
 323
 324        c->tagpool = p9_idpool_create();
 325        if (IS_ERR(c->tagpool)) {
 326                err = PTR_ERR(c->tagpool);
 327                goto error;
 328        }
 329        err = p9_idpool_get(c->tagpool); /* reserve tag 0 */
 330        if (err < 0) {
 331                p9_idpool_destroy(c->tagpool);
 332                goto error;
 333        }
 334        c->max_tag = 0;
 335error:
 336        return err;
 337}
 338
 339/**
 340 * p9_tag_cleanup - cleans up tags structure and reclaims resources
 341 * @c:  v9fs client struct
 342 *
 343 * This frees resources associated with the tags structure
 344 *
 345 */
 346static void p9_tag_cleanup(struct p9_client *c)
 347{
 348        int row, col;
 349
 350        /* check to insure all requests are idle */
 351        for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 352                for (col = 0; col < P9_ROW_MAXTAG; col++) {
 353                        if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
 354                                P9_DPRINTK(P9_DEBUG_MUX,
 355                                  "Attempting to cleanup non-free tag %d,%d\n",
 356                                  row, col);
 357                                /* TODO: delay execution of cleanup */
 358                                return;
 359                        }
 360                }
 361        }
 362
 363        if (c->tagpool) {
 364                p9_idpool_put(0, c->tagpool); /* free reserved tag 0 */
 365                p9_idpool_destroy(c->tagpool);
 366        }
 367
 368        /* free requests associated with tags */
 369        for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 370                for (col = 0; col < P9_ROW_MAXTAG; col++) {
 371                        kfree(c->reqs[row][col].wq);
 372                        kfree(c->reqs[row][col].tc);
 373                        kfree(c->reqs[row][col].rc);
 374                }
 375                kfree(c->reqs[row]);
 376        }
 377        c->max_tag = 0;
 378}
 379
 380/**
 381 * p9_free_req - free a request and clean-up as necessary
 382 * c: client state
 383 * r: request to release
 384 *
 385 */
 386
 387static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
 388{
 389        int tag = r->tc->tag;
 390        P9_DPRINTK(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
 391
 392        r->status = REQ_STATUS_IDLE;
 393        if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
 394                p9_idpool_put(tag, c->tagpool);
 395}
 396
 397/**
 398 * p9_client_cb - call back from transport to client
 399 * c: client state
 400 * req: request received
 401 *
 402 */
 403void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
 404{
 405        P9_DPRINTK(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
 406        wake_up(req->wq);
 407        P9_DPRINTK(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
 408}
 409EXPORT_SYMBOL(p9_client_cb);
 410
 411/**
 412 * p9_parse_header - parse header arguments out of a packet
 413 * @pdu: packet to parse
 414 * @size: size of packet
 415 * @type: type of request
 416 * @tag: tag of packet
 417 * @rewind: set if we need to rewind offset afterwards
 418 */
 419
 420int
 421p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
 422                                                                int rewind)
 423{
 424        int8_t r_type;
 425        int16_t r_tag;
 426        int32_t r_size;
 427        int offset = pdu->offset;
 428        int err;
 429
 430        pdu->offset = 0;
 431        if (pdu->size == 0)
 432                pdu->size = 7;
 433
 434        err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
 435        if (err)
 436                goto rewind_and_exit;
 437
 438        pdu->size = r_size;
 439        pdu->id = r_type;
 440        pdu->tag = r_tag;
 441
 442        P9_DPRINTK(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n", pdu->size,
 443                                                        pdu->id, pdu->tag);
 444
 445        if (type)
 446                *type = r_type;
 447        if (tag)
 448                *tag = r_tag;
 449        if (size)
 450                *size = r_size;
 451
 452
 453rewind_and_exit:
 454        if (rewind)
 455                pdu->offset = offset;
 456        return err;
 457}
 458EXPORT_SYMBOL(p9_parse_header);
 459
 460/**
 461 * p9_check_errors - check 9p packet for error return and process it
 462 * @c: current client instance
 463 * @req: request to parse and check for error conditions
 464 *
 465 * returns error code if one is discovered, otherwise returns 0
 466 *
 467 * this will have to be more complicated if we have multiple
 468 * error packet types
 469 */
 470
 471static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 472{
 473        int8_t type;
 474        int err;
 475        int ecode;
 476
 477        err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 478        if (err) {
 479                P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 480                return err;
 481        }
 482
 483        if (type != P9_RERROR && type != P9_RLERROR)
 484                return 0;
 485
 486        if (!p9_is_proto_dotl(c)) {
 487                char *ename;
 488
 489                if (req->tc->pbuf_size) {
 490                        /* Handle user buffers */
 491                        size_t len = req->rc->size - req->rc->offset;
 492                        if (req->tc->pubuf) {
 493                                /* User Buffer */
 494                                err = copy_from_user(
 495                                        &req->rc->sdata[req->rc->offset],
 496                                        req->tc->pubuf, len);
 497                                if (err) {
 498                                        err = -EFAULT;
 499                                        goto out_err;
 500                                }
 501                        } else {
 502                                /* Kernel Buffer */
 503                                memmove(&req->rc->sdata[req->rc->offset],
 504                                                req->tc->pkbuf, len);
 505                        }
 506                }
 507                err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 508                                &ename, &ecode);
 509                if (err)
 510                        goto out_err;
 511
 512                if (p9_is_proto_dotu(c))
 513                        err = -ecode;
 514
 515                if (!err || !IS_ERR_VALUE(err)) {
 516                        err = p9_errstr2errno(ename, strlen(ename));
 517
 518                        P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode,
 519                                        ename);
 520
 521                        kfree(ename);
 522                }
 523        } else {
 524                err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 525                err = -ecode;
 526
 527                P9_DPRINTK(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 528        }
 529
 530
 531        return err;
 532
 533out_err:
 534        P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 535
 536        return err;
 537}
 538
 539static struct p9_req_t *
 540p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
 541
 542/**
 543 * p9_client_flush - flush (cancel) a request
 544 * @c: client state
 545 * @oldreq: request to cancel
 546 *
 547 * This sents a flush for a particular request and links
 548 * the flush request to the original request.  The current
 549 * code only supports a single flush request although the protocol
 550 * allows for multiple flush requests to be sent for a single request.
 551 *
 552 */
 553
 554static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 555{
 556        struct p9_req_t *req;
 557        int16_t oldtag;
 558        int err;
 559
 560        err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
 561        if (err)
 562                return err;
 563
 564        P9_DPRINTK(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
 565
 566        req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
 567        if (IS_ERR(req))
 568                return PTR_ERR(req);
 569
 570
 571        /* if we haven't received a response for oldreq,
 572           remove it from the list. */
 573        spin_lock(&c->lock);
 574        if (oldreq->status == REQ_STATUS_FLSH)
 575                list_del(&oldreq->req_list);
 576        spin_unlock(&c->lock);
 577
 578        p9_free_req(c, req);
 579        return 0;
 580}
 581
 582/**
 583 * p9_client_rpc - issue a request and wait for a response
 584 * @c: client session
 585 * @type: type of request
 586 * @fmt: protocol format string (see protocol.c)
 587 *
 588 * Returns request structure (which client must free using p9_free_req)
 589 */
 590
 591static struct p9_req_t *
 592p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 593{
 594        va_list ap;
 595        int tag, err;
 596        struct p9_req_t *req;
 597        unsigned long flags;
 598        int sigpending;
 599
 600        P9_DPRINTK(P9_DEBUG_MUX, "client %p op %d\n", c, type);
 601
 602        /* we allow for any status other than disconnected */
 603        if (c->status == Disconnected)
 604                return ERR_PTR(-EIO);
 605
 606        /* if status is begin_disconnected we allow only clunk request */
 607        if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
 608                return ERR_PTR(-EIO);
 609
 610        if (signal_pending(current)) {
 611                sigpending = 1;
 612                clear_thread_flag(TIF_SIGPENDING);
 613        } else
 614                sigpending = 0;
 615
 616        tag = P9_NOTAG;
 617        if (type != P9_TVERSION) {
 618                tag = p9_idpool_get(c->tagpool);
 619                if (tag < 0)
 620                        return ERR_PTR(-ENOMEM);
 621        }
 622
 623        req = p9_tag_alloc(c, tag);
 624        if (IS_ERR(req))
 625                return req;
 626
 627        /* marshall the data */
 628        p9pdu_prepare(req->tc, tag, type);
 629        va_start(ap, fmt);
 630        err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
 631        va_end(ap);
 632        if (err)
 633                goto reterr;
 634        p9pdu_finalize(req->tc);
 635
 636        err = c->trans_mod->request(c, req);
 637        if (err < 0) {
 638                if (err != -ERESTARTSYS && err != -EFAULT)
 639                        c->status = Disconnected;
 640                goto reterr;
 641        }
 642
 643        P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d\n", req->wq, tag);
 644        err = wait_event_interruptible(*req->wq,
 645                                                req->status >= REQ_STATUS_RCVD);
 646        P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d returned %d\n",
 647                                                req->wq, tag, err);
 648
 649        if (req->status == REQ_STATUS_ERROR) {
 650                P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 651                err = req->t_err;
 652        }
 653
 654        if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 655                P9_DPRINTK(P9_DEBUG_MUX, "flushing\n");
 656                sigpending = 1;
 657                clear_thread_flag(TIF_SIGPENDING);
 658
 659                if (c->trans_mod->cancel(c, req))
 660                        p9_client_flush(c, req);
 661
 662                /* if we received the response anyway, don't signal error */
 663                if (req->status == REQ_STATUS_RCVD)
 664                        err = 0;
 665        }
 666
 667        if (sigpending) {
 668                spin_lock_irqsave(&current->sighand->siglock, flags);
 669                recalc_sigpending();
 670                spin_unlock_irqrestore(&current->sighand->siglock, flags);
 671        }
 672
 673        if (err < 0)
 674                goto reterr;
 675
 676        err = p9_check_errors(c, req);
 677        if (!err) {
 678                P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d\n", c, type);
 679                return req;
 680        }
 681
 682reterr:
 683        P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d error: %d\n", c, type,
 684                                                                        err);
 685        p9_free_req(c, req);
 686        return ERR_PTR(err);
 687}
 688
 689static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 690{
 691        int ret;
 692        struct p9_fid *fid;
 693        unsigned long flags;
 694
 695        P9_DPRINTK(P9_DEBUG_FID, "clnt %p\n", clnt);
 696        fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
 697        if (!fid)
 698                return ERR_PTR(-ENOMEM);
 699
 700        ret = p9_idpool_get(clnt->fidpool);
 701        if (ret < 0) {
 702                ret = -ENOSPC;
 703                goto error;
 704        }
 705        fid->fid = ret;
 706
 707        memset(&fid->qid, 0, sizeof(struct p9_qid));
 708        fid->mode = -1;
 709        fid->uid = current_fsuid();
 710        fid->clnt = clnt;
 711        fid->rdir = NULL;
 712        spin_lock_irqsave(&clnt->lock, flags);
 713        list_add(&fid->flist, &clnt->fidlist);
 714        spin_unlock_irqrestore(&clnt->lock, flags);
 715
 716        return fid;
 717
 718error:
 719        kfree(fid);
 720        return ERR_PTR(ret);
 721}
 722
 723static void p9_fid_destroy(struct p9_fid *fid)
 724{
 725        struct p9_client *clnt;
 726        unsigned long flags;
 727
 728        P9_DPRINTK(P9_DEBUG_FID, "fid %d\n", fid->fid);
 729        clnt = fid->clnt;
 730        p9_idpool_put(fid->fid, clnt->fidpool);
 731        spin_lock_irqsave(&clnt->lock, flags);
 732        list_del(&fid->flist);
 733        spin_unlock_irqrestore(&clnt->lock, flags);
 734        kfree(fid->rdir);
 735        kfree(fid);
 736}
 737
 738static int p9_client_version(struct p9_client *c)
 739{
 740        int err = 0;
 741        struct p9_req_t *req;
 742        char *version;
 743        int msize;
 744
 745        P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
 746                                                c->msize, c->proto_version);
 747
 748        switch (c->proto_version) {
 749        case p9_proto_2000L:
 750                req = p9_client_rpc(c, P9_TVERSION, "ds",
 751                                        c->msize, "9P2000.L");
 752                break;
 753        case p9_proto_2000u:
 754                req = p9_client_rpc(c, P9_TVERSION, "ds",
 755                                        c->msize, "9P2000.u");
 756                break;
 757        case p9_proto_legacy:
 758                req = p9_client_rpc(c, P9_TVERSION, "ds",
 759                                        c->msize, "9P2000");
 760                break;
 761        default:
 762                return -EINVAL;
 763                break;
 764        }
 765
 766        if (IS_ERR(req))
 767                return PTR_ERR(req);
 768
 769        err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
 770        if (err) {
 771                P9_DPRINTK(P9_DEBUG_9P, "version error %d\n", err);
 772                P9_DUMP_PKT(1, req->rc);
 773                goto error;
 774        }
 775
 776        P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
 777        if (!strncmp(version, "9P2000.L", 8))
 778                c->proto_version = p9_proto_2000L;
 779        else if (!strncmp(version, "9P2000.u", 8))
 780                c->proto_version = p9_proto_2000u;
 781        else if (!strncmp(version, "9P2000", 6))
 782                c->proto_version = p9_proto_legacy;
 783        else {
 784                err = -EREMOTEIO;
 785                goto error;
 786        }
 787
 788        if (msize < c->msize)
 789                c->msize = msize;
 790
 791error:
 792        kfree(version);
 793        p9_free_req(c, req);
 794
 795        return err;
 796}
 797
 798struct p9_client *p9_client_create(const char *dev_name, char *options)
 799{
 800        int err;
 801        struct p9_client *clnt;
 802
 803        err = 0;
 804        clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
 805        if (!clnt)
 806                return ERR_PTR(-ENOMEM);
 807
 808        clnt->trans_mod = NULL;
 809        clnt->trans = NULL;
 810        spin_lock_init(&clnt->lock);
 811        INIT_LIST_HEAD(&clnt->fidlist);
 812
 813        err = p9_tag_init(clnt);
 814        if (err < 0)
 815                goto free_client;
 816
 817        err = parse_opts(options, clnt);
 818        if (err < 0)
 819                goto destroy_tagpool;
 820
 821        if (!clnt->trans_mod)
 822                clnt->trans_mod = v9fs_get_default_trans();
 823
 824        if (clnt->trans_mod == NULL) {
 825                err = -EPROTONOSUPPORT;
 826                P9_DPRINTK(P9_DEBUG_ERROR,
 827                                "No transport defined or default transport\n");
 828                goto destroy_tagpool;
 829        }
 830
 831        clnt->fidpool = p9_idpool_create();
 832        if (IS_ERR(clnt->fidpool)) {
 833                err = PTR_ERR(clnt->fidpool);
 834                goto put_trans;
 835        }
 836
 837        P9_DPRINTK(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
 838                clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
 839
 840        err = clnt->trans_mod->create(clnt, dev_name, options);
 841        if (err)
 842                goto destroy_fidpool;
 843
 844        if (clnt->msize > clnt->trans_mod->maxsize)
 845                clnt->msize = clnt->trans_mod->maxsize;
 846
 847        err = p9_client_version(clnt);
 848        if (err)
 849                goto close_trans;
 850
 851        return clnt;
 852
 853close_trans:
 854        clnt->trans_mod->close(clnt);
 855destroy_fidpool:
 856        p9_idpool_destroy(clnt->fidpool);
 857put_trans:
 858        v9fs_put_trans(clnt->trans_mod);
 859destroy_tagpool:
 860        p9_idpool_destroy(clnt->tagpool);
 861free_client:
 862        kfree(clnt);
 863        return ERR_PTR(err);
 864}
 865EXPORT_SYMBOL(p9_client_create);
 866
 867void p9_client_destroy(struct p9_client *clnt)
 868{
 869        struct p9_fid *fid, *fidptr;
 870
 871        P9_DPRINTK(P9_DEBUG_MUX, "clnt %p\n", clnt);
 872
 873        if (clnt->trans_mod)
 874                clnt->trans_mod->close(clnt);
 875
 876        v9fs_put_trans(clnt->trans_mod);
 877
 878        list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
 879                printk(KERN_INFO "Found fid %d not clunked\n", fid->fid);
 880                p9_fid_destroy(fid);
 881        }
 882
 883        if (clnt->fidpool)
 884                p9_idpool_destroy(clnt->fidpool);
 885
 886        p9_tag_cleanup(clnt);
 887
 888        kfree(clnt);
 889}
 890EXPORT_SYMBOL(p9_client_destroy);
 891
 892void p9_client_disconnect(struct p9_client *clnt)
 893{
 894        P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
 895        clnt->status = Disconnected;
 896}
 897EXPORT_SYMBOL(p9_client_disconnect);
 898
 899void p9_client_begin_disconnect(struct p9_client *clnt)
 900{
 901        P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
 902        clnt->status = BeginDisconnect;
 903}
 904EXPORT_SYMBOL(p9_client_begin_disconnect);
 905
 906struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
 907        char *uname, u32 n_uname, char *aname)
 908{
 909        int err;
 910        struct p9_req_t *req;
 911        struct p9_fid *fid;
 912        struct p9_qid qid;
 913
 914        P9_DPRINTK(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
 915                                        afid ? afid->fid : -1, uname, aname);
 916        err = 0;
 917
 918        fid = p9_fid_create(clnt);
 919        if (IS_ERR(fid)) {
 920                err = PTR_ERR(fid);
 921                fid = NULL;
 922                goto error;
 923        }
 924
 925        req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
 926                        afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
 927        if (IS_ERR(req)) {
 928                err = PTR_ERR(req);
 929                goto error;
 930        }
 931
 932        err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
 933        if (err) {
 934                P9_DUMP_PKT(1, req->rc);
 935                p9_free_req(clnt, req);
 936                goto error;
 937        }
 938
 939        P9_DPRINTK(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
 940                                        qid.type,
 941                                        (unsigned long long)qid.path,
 942                                        qid.version);
 943
 944        memmove(&fid->qid, &qid, sizeof(struct p9_qid));
 945
 946        p9_free_req(clnt, req);
 947        return fid;
 948
 949error:
 950        if (fid)
 951                p9_fid_destroy(fid);
 952        return ERR_PTR(err);
 953}
 954EXPORT_SYMBOL(p9_client_attach);
 955
 956struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
 957                char **wnames, int clone)
 958{
 959        int err;
 960        struct p9_client *clnt;
 961        struct p9_fid *fid;
 962        struct p9_qid *wqids;
 963        struct p9_req_t *req;
 964        uint16_t nwqids, count;
 965
 966        err = 0;
 967        wqids = NULL;
 968        clnt = oldfid->clnt;
 969        if (clone) {
 970                fid = p9_fid_create(clnt);
 971                if (IS_ERR(fid)) {
 972                        err = PTR_ERR(fid);
 973                        fid = NULL;
 974                        goto error;
 975                }
 976
 977                fid->uid = oldfid->uid;
 978        } else
 979                fid = oldfid;
 980
 981
 982        P9_DPRINTK(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
 983                oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
 984
 985        req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
 986                                                                nwname, wnames);
 987        if (IS_ERR(req)) {
 988                err = PTR_ERR(req);
 989                goto error;
 990        }
 991
 992        err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
 993        if (err) {
 994                P9_DUMP_PKT(1, req->rc);
 995                p9_free_req(clnt, req);
 996                goto clunk_fid;
 997        }
 998        p9_free_req(clnt, req);
 999
1000        P9_DPRINTK(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1001
1002        if (nwqids != nwname) {
1003                err = -ENOENT;
1004                goto clunk_fid;
1005        }
1006
1007        for (count = 0; count < nwqids; count++)
1008                P9_DPRINTK(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
1009                        count, wqids[count].type,
1010                        (unsigned long long)wqids[count].path,
1011                        wqids[count].version);
1012
1013        if (nwname)
1014                memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1015        else
1016                fid->qid = oldfid->qid;
1017
1018        kfree(wqids);
1019        return fid;
1020
1021clunk_fid:
1022        kfree(wqids);
1023        p9_client_clunk(fid);
1024        fid = NULL;
1025
1026error:
1027        if (fid && (fid != oldfid))
1028                p9_fid_destroy(fid);
1029
1030        return ERR_PTR(err);
1031}
1032EXPORT_SYMBOL(p9_client_walk);
1033
1034int p9_client_open(struct p9_fid *fid, int mode)
1035{
1036        int err;
1037        struct p9_client *clnt;
1038        struct p9_req_t *req;
1039        struct p9_qid qid;
1040        int iounit;
1041
1042        clnt = fid->clnt;
1043        P9_DPRINTK(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1044                p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1045        err = 0;
1046
1047        if (fid->mode != -1)
1048                return -EINVAL;
1049
1050        if (p9_is_proto_dotl(clnt))
1051                req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1052        else
1053                req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1054        if (IS_ERR(req)) {
1055                err = PTR_ERR(req);
1056                goto error;
1057        }
1058
1059        err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1060        if (err) {
1061                P9_DUMP_PKT(1, req->rc);
1062                goto free_and_error;
1063        }
1064
1065        P9_DPRINTK(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1066                p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1067                (unsigned long long)qid.path, qid.version, iounit);
1068
1069        fid->mode = mode;
1070        fid->iounit = iounit;
1071
1072free_and_error:
1073        p9_free_req(clnt, req);
1074error:
1075        return err;
1076}
1077EXPORT_SYMBOL(p9_client_open);
1078
1079int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
1080                gid_t gid, struct p9_qid *qid)
1081{
1082        int err = 0;
1083        struct p9_client *clnt;
1084        struct p9_req_t *req;
1085        int iounit;
1086
1087        P9_DPRINTK(P9_DEBUG_9P,
1088                        ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1089                        ofid->fid, name, flags, mode, gid);
1090        clnt = ofid->clnt;
1091
1092        if (ofid->mode != -1)
1093                return -EINVAL;
1094
1095        req = p9_client_rpc(clnt, P9_TLCREATE, "dsddd", ofid->fid, name, flags,
1096                        mode, gid);
1097        if (IS_ERR(req)) {
1098                err = PTR_ERR(req);
1099                goto error;
1100        }
1101
1102        err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1103        if (err) {
1104                P9_DUMP_PKT(1, req->rc);
1105                goto free_and_error;
1106        }
1107
1108        P9_DPRINTK(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1109                        qid->type,
1110                        (unsigned long long)qid->path,
1111                        qid->version, iounit);
1112
1113        ofid->mode = mode;
1114        ofid->iounit = iounit;
1115
1116free_and_error:
1117        p9_free_req(clnt, req);
1118error:
1119        return err;
1120}
1121EXPORT_SYMBOL(p9_client_create_dotl);
1122
1123int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1124                     char *extension)
1125{
1126        int err;
1127        struct p9_client *clnt;
1128        struct p9_req_t *req;
1129        struct p9_qid qid;
1130        int iounit;
1131
1132        P9_DPRINTK(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1133                                                fid->fid, name, perm, mode);
1134        err = 0;
1135        clnt = fid->clnt;
1136
1137        if (fid->mode != -1)
1138                return -EINVAL;
1139
1140        req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1141                                mode, extension);
1142        if (IS_ERR(req)) {
1143                err = PTR_ERR(req);
1144                goto error;
1145        }
1146
1147        err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1148        if (err) {
1149                P9_DUMP_PKT(1, req->rc);
1150                goto free_and_error;
1151        }
1152
1153        P9_DPRINTK(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1154                                qid.type,
1155                                (unsigned long long)qid.path,
1156                                qid.version, iounit);
1157
1158        fid->mode = mode;
1159        fid->iounit = iounit;
1160
1161free_and_error:
1162        p9_free_req(clnt, req);
1163error:
1164        return err;
1165}
1166EXPORT_SYMBOL(p9_client_fcreate);
1167
1168int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, gid_t gid,
1169                struct p9_qid *qid)
1170{
1171        int err = 0;
1172        struct p9_client *clnt;
1173        struct p9_req_t *req;
1174
1175        P9_DPRINTK(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1176                        dfid->fid, name, symtgt);
1177        clnt = dfid->clnt;
1178
1179        req = p9_client_rpc(clnt, P9_TSYMLINK, "dssd", dfid->fid, name, symtgt,
1180                        gid);
1181        if (IS_ERR(req)) {
1182                err = PTR_ERR(req);
1183                goto error;
1184        }
1185
1186        err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1187        if (err) {
1188                P9_DUMP_PKT(1, req->rc);
1189                goto free_and_error;
1190        }
1191
1192        P9_DPRINTK(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1193                        qid->type, (unsigned long long)qid->path, qid->version);
1194
1195free_and_error:
1196        p9_free_req(clnt, req);
1197error:
1198        return err;
1199}
1200EXPORT_SYMBOL(p9_client_symlink);
1201
1202int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
1203{
1204        struct p9_client *clnt;
1205        struct p9_req_t *req;
1206
1207        P9_DPRINTK(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1208                        dfid->fid, oldfid->fid, newname);
1209        clnt = dfid->clnt;
1210        req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1211                        newname);
1212        if (IS_ERR(req))
1213                return PTR_ERR(req);
1214
1215        P9_DPRINTK(P9_DEBUG_9P, "<<< RLINK\n");
1216        p9_free_req(clnt, req);
1217        return 0;
1218}
1219EXPORT_SYMBOL(p9_client_link);
1220
1221int p9_client_fsync(struct p9_fid *fid, int datasync)
1222{
1223        int err;
1224        struct p9_client *clnt;
1225        struct p9_req_t *req;
1226
1227        P9_DPRINTK(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1228                        fid->fid, datasync);
1229        err = 0;
1230        clnt = fid->clnt;
1231
1232        req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1233        if (IS_ERR(req)) {
1234                err = PTR_ERR(req);
1235                goto error;
1236        }
1237
1238        P9_DPRINTK(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1239
1240        p9_free_req(clnt, req);
1241
1242error:
1243        return err;
1244}
1245EXPORT_SYMBOL(p9_client_fsync);
1246
1247int p9_client_clunk(struct p9_fid *fid)
1248{
1249        int err;
1250        struct p9_client *clnt;
1251        struct p9_req_t *req;
1252
1253        if (!fid) {
1254                P9_EPRINTK(KERN_WARNING, "Trying to clunk with NULL fid\n");
1255                dump_stack();
1256                return 0;
1257        }
1258
1259        P9_DPRINTK(P9_DEBUG_9P, ">>> TCLUNK fid %d\n", fid->fid);
1260        err = 0;
1261        clnt = fid->clnt;
1262
1263        req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1264        if (IS_ERR(req)) {
1265                err = PTR_ERR(req);
1266                goto error;
1267        }
1268
1269        P9_DPRINTK(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1270
1271        p9_free_req(clnt, req);
1272error:
1273        /*
1274         * Fid is not valid even after a failed clunk
1275         */
1276        p9_fid_destroy(fid);
1277        return err;
1278}
1279EXPORT_SYMBOL(p9_client_clunk);
1280
1281int p9_client_remove(struct p9_fid *fid)
1282{
1283        int err;
1284        struct p9_client *clnt;
1285        struct p9_req_t *req;
1286
1287        P9_DPRINTK(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1288        err = 0;
1289        clnt = fid->clnt;
1290
1291        req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1292        if (IS_ERR(req)) {
1293                err = PTR_ERR(req);
1294                goto error;
1295        }
1296
1297        P9_DPRINTK(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1298
1299        p9_free_req(clnt, req);
1300error:
1301        p9_fid_destroy(fid);
1302        return err;
1303}
1304EXPORT_SYMBOL(p9_client_remove);
1305
1306int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1307{
1308        int err = 0;
1309        struct p9_req_t *req;
1310        struct p9_client *clnt;
1311
1312        P9_DPRINTK(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1313                   dfid->fid, name, flags);
1314
1315        clnt = dfid->clnt;
1316        req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1317        if (IS_ERR(req)) {
1318                err = PTR_ERR(req);
1319                goto error;
1320        }
1321        P9_DPRINTK(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1322
1323        p9_free_req(clnt, req);
1324error:
1325        return err;
1326}
1327EXPORT_SYMBOL(p9_client_unlinkat);
1328
1329int
1330p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1331                                                                u32 count)
1332{
1333        int err, rsize;
1334        struct p9_client *clnt;
1335        struct p9_req_t *req;
1336        char *dataptr;
1337
1338        P9_DPRINTK(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n", fid->fid,
1339                                        (long long unsigned) offset, count);
1340        err = 0;
1341        clnt = fid->clnt;
1342
1343        rsize = fid->iounit;
1344        if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1345                rsize = clnt->msize - P9_IOHDRSZ;
1346
1347        if (count < rsize)
1348                rsize = count;
1349
1350        /* Don't bother zerocopy for small IO (< 1024) */
1351        if (((clnt->trans_mod->pref & P9_TRANS_PREF_PAYLOAD_MASK) ==
1352                        P9_TRANS_PREF_PAYLOAD_SEP) && (rsize > 1024)) {
1353                req = p9_client_rpc(clnt, P9_TREAD, "dqE", fid->fid, offset,
1354                                rsize, data, udata);
1355        } else {
1356                req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1357                                rsize);
1358        }
1359        if (IS_ERR(req)) {
1360                err = PTR_ERR(req);
1361                goto error;
1362        }
1363
1364        err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1365        if (err) {
1366                P9_DUMP_PKT(1, req->rc);
1367                goto free_and_error;
1368        }
1369
1370        P9_DPRINTK(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1371        P9_DUMP_PKT(1, req->rc);
1372
1373        if (!req->tc->pbuf_size) {
1374                if (data) {
1375                        memmove(data, dataptr, count);
1376                } else {
1377                        err = copy_to_user(udata, dataptr, count);
1378                        if (err) {
1379                                err = -EFAULT;
1380                                goto free_and_error;
1381                        }
1382                }
1383        }
1384        p9_free_req(clnt, req);
1385        return count;
1386
1387free_and_error:
1388        p9_free_req(clnt, req);
1389error:
1390        return err;
1391}
1392EXPORT_SYMBOL(p9_client_read);
1393
1394int
1395p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1396                                                        u64 offset, u32 count)
1397{
1398        int err, rsize;
1399        struct p9_client *clnt;
1400        struct p9_req_t *req;
1401
1402        P9_DPRINTK(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1403                                fid->fid, (long long unsigned) offset, count);
1404        err = 0;
1405        clnt = fid->clnt;
1406
1407        rsize = fid->iounit;
1408        if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1409                rsize = clnt->msize - P9_IOHDRSZ;
1410
1411        if (count < rsize)
1412                rsize = count;
1413
1414        /* Don't bother zerocopy form small IO (< 1024) */
1415        if (((clnt->trans_mod->pref & P9_TRANS_PREF_PAYLOAD_MASK) ==
1416                                P9_TRANS_PREF_PAYLOAD_SEP) && (rsize > 1024)) {
1417                req = p9_client_rpc(clnt, P9_TWRITE, "dqE", fid->fid, offset,
1418                                rsize, data, udata);
1419        } else {
1420
1421                if (data)
1422                        req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid,
1423                                        offset, rsize, data);
1424                else
1425                        req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid,
1426                                        offset, rsize, udata);
1427        }
1428        if (IS_ERR(req)) {
1429                err = PTR_ERR(req);
1430                goto error;
1431        }
1432
1433        err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1434        if (err) {
1435                P9_DUMP_PKT(1, req->rc);
1436                goto free_and_error;
1437        }
1438
1439        P9_DPRINTK(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1440
1441        p9_free_req(clnt, req);
1442        return count;
1443
1444free_and_error:
1445        p9_free_req(clnt, req);
1446error:
1447        return err;
1448}
1449EXPORT_SYMBOL(p9_client_write);
1450
1451struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1452{
1453        int err;
1454        struct p9_client *clnt;
1455        struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1456        struct p9_req_t *req;
1457        u16 ignored;
1458
1459        P9_DPRINTK(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1460
1461        if (!ret)
1462                return ERR_PTR(-ENOMEM);
1463
1464        err = 0;
1465        clnt = fid->clnt;
1466
1467        req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1468        if (IS_ERR(req)) {
1469                err = PTR_ERR(req);
1470                goto error;
1471        }
1472
1473        err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1474        if (err) {
1475                P9_DUMP_PKT(1, req->rc);
1476                p9_free_req(clnt, req);
1477                goto error;
1478        }
1479
1480        P9_DPRINTK(P9_DEBUG_9P,
1481                "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1482                "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1483                "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1484                "<<<    uid=%d gid=%d n_muid=%d\n",
1485                ret->size, ret->type, ret->dev, ret->qid.type,
1486                (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1487                ret->atime, ret->mtime, (unsigned long long)ret->length,
1488                ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1489                ret->n_uid, ret->n_gid, ret->n_muid);
1490
1491        p9_free_req(clnt, req);
1492        return ret;
1493
1494error:
1495        kfree(ret);
1496        return ERR_PTR(err);
1497}
1498EXPORT_SYMBOL(p9_client_stat);
1499
1500struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1501                                                        u64 request_mask)
1502{
1503        int err;
1504        struct p9_client *clnt;
1505        struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1506                                                                GFP_KERNEL);
1507        struct p9_req_t *req;
1508
1509        P9_DPRINTK(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1510                                                        fid->fid, request_mask);
1511
1512        if (!ret)
1513                return ERR_PTR(-ENOMEM);
1514
1515        err = 0;
1516        clnt = fid->clnt;
1517
1518        req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1519        if (IS_ERR(req)) {
1520                err = PTR_ERR(req);
1521                goto error;
1522        }
1523
1524        err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1525        if (err) {
1526                P9_DUMP_PKT(1, req->rc);
1527                p9_free_req(clnt, req);
1528                goto error;
1529        }
1530
1531        P9_DPRINTK(P9_DEBUG_9P,
1532                "<<< RGETATTR st_result_mask=%lld\n"
1533                "<<< qid=%x.%llx.%x\n"
1534                "<<< st_mode=%8.8x st_nlink=%llu\n"
1535                "<<< st_uid=%d st_gid=%d\n"
1536                "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1537                "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1538                "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1539                "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1540                "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1541                "<<< st_gen=%lld st_data_version=%lld",
1542                ret->st_result_mask, ret->qid.type, ret->qid.path,
1543                ret->qid.version, ret->st_mode, ret->st_nlink, ret->st_uid,
1544                ret->st_gid, ret->st_rdev, ret->st_size, ret->st_blksize,
1545                ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1546                ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1547                ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1548                ret->st_gen, ret->st_data_version);
1549
1550        p9_free_req(clnt, req);
1551        return ret;
1552
1553error:
1554        kfree(ret);
1555        return ERR_PTR(err);
1556}
1557EXPORT_SYMBOL(p9_client_getattr_dotl);
1558
1559static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1560{
1561        int ret;
1562
1563        /* NOTE: size shouldn't include its own length */
1564        /* size[2] type[2] dev[4] qid[13] */
1565        /* mode[4] atime[4] mtime[4] length[8]*/
1566        /* name[s] uid[s] gid[s] muid[s] */
1567        ret = 2+4+13+4+4+4+8+2+2+2+2;
1568
1569        if (wst->name)
1570                ret += strlen(wst->name);
1571        if (wst->uid)
1572                ret += strlen(wst->uid);
1573        if (wst->gid)
1574                ret += strlen(wst->gid);
1575        if (wst->muid)
1576                ret += strlen(wst->muid);
1577
1578        if ((proto_version == p9_proto_2000u) ||
1579                (proto_version == p9_proto_2000L)) {
1580                ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1581                if (wst->extension)
1582                        ret += strlen(wst->extension);
1583        }
1584
1585        return ret;
1586}
1587
1588int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1589{
1590        int err;
1591        struct p9_req_t *req;
1592        struct p9_client *clnt;
1593
1594        err = 0;
1595        clnt = fid->clnt;
1596        wst->size = p9_client_statsize(wst, clnt->proto_version);
1597        P9_DPRINTK(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1598        P9_DPRINTK(P9_DEBUG_9P,
1599                "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1600                "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1601                "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1602                "     uid=%d gid=%d n_muid=%d\n",
1603                wst->size, wst->type, wst->dev, wst->qid.type,
1604                (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1605                wst->atime, wst->mtime, (unsigned long long)wst->length,
1606                wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1607                wst->n_uid, wst->n_gid, wst->n_muid);
1608
1609        req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1610        if (IS_ERR(req)) {
1611                err = PTR_ERR(req);
1612                goto error;
1613        }
1614
1615        P9_DPRINTK(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1616
1617        p9_free_req(clnt, req);
1618error:
1619        return err;
1620}
1621EXPORT_SYMBOL(p9_client_wstat);
1622
1623int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1624{
1625        int err;
1626        struct p9_req_t *req;
1627        struct p9_client *clnt;
1628
1629        err = 0;
1630        clnt = fid->clnt;
1631        P9_DPRINTK(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1632        P9_DPRINTK(P9_DEBUG_9P,
1633                "    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1634                "    atime_sec=%lld atime_nsec=%lld\n"
1635                "    mtime_sec=%lld mtime_nsec=%lld\n",
1636                p9attr->valid, p9attr->mode, p9attr->uid, p9attr->gid,
1637                p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1638                p9attr->mtime_sec, p9attr->mtime_nsec);
1639
1640        req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1641
1642        if (IS_ERR(req)) {
1643                err = PTR_ERR(req);
1644                goto error;
1645        }
1646        P9_DPRINTK(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1647        p9_free_req(clnt, req);
1648error:
1649        return err;
1650}
1651EXPORT_SYMBOL(p9_client_setattr);
1652
1653int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1654{
1655        int err;
1656        struct p9_req_t *req;
1657        struct p9_client *clnt;
1658
1659        err = 0;
1660        clnt = fid->clnt;
1661
1662        P9_DPRINTK(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1663
1664        req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1665        if (IS_ERR(req)) {
1666                err = PTR_ERR(req);
1667                goto error;
1668        }
1669
1670        err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1671                &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1672                &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1673        if (err) {
1674                P9_DUMP_PKT(1, req->rc);
1675                p9_free_req(clnt, req);
1676                goto error;
1677        }
1678
1679        P9_DPRINTK(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1680                "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1681                "fsid %llu namelen %ld\n",
1682                fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1683                sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1684                sb->fsid, (long int)sb->namelen);
1685
1686        p9_free_req(clnt, req);
1687error:
1688        return err;
1689}
1690EXPORT_SYMBOL(p9_client_statfs);
1691
1692int p9_client_rename(struct p9_fid *fid,
1693                     struct p9_fid *newdirfid, const char *name)
1694{
1695        int err;
1696        struct p9_req_t *req;
1697        struct p9_client *clnt;
1698
1699        err = 0;
1700        clnt = fid->clnt;
1701
1702        P9_DPRINTK(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1703                        fid->fid, newdirfid->fid, name);
1704
1705        req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1706                        newdirfid->fid, name);
1707        if (IS_ERR(req)) {
1708                err = PTR_ERR(req);
1709                goto error;
1710        }
1711
1712        P9_DPRINTK(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1713
1714        p9_free_req(clnt, req);
1715error:
1716        return err;
1717}
1718EXPORT_SYMBOL(p9_client_rename);
1719
1720int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1721                       struct p9_fid *newdirfid, const char *new_name)
1722{
1723        int err;
1724        struct p9_req_t *req;
1725        struct p9_client *clnt;
1726
1727        err = 0;
1728        clnt = olddirfid->clnt;
1729
1730        P9_DPRINTK(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1731                   " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1732                   newdirfid->fid, new_name);
1733
1734        req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1735                            old_name, newdirfid->fid, new_name);
1736        if (IS_ERR(req)) {
1737                err = PTR_ERR(req);
1738                goto error;
1739        }
1740
1741        P9_DPRINTK(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
1742                   newdirfid->fid, new_name);
1743
1744        p9_free_req(clnt, req);
1745error:
1746        return err;
1747}
1748EXPORT_SYMBOL(p9_client_renameat);
1749
1750/*
1751 * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1752 */
1753struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1754                                const char *attr_name, u64 *attr_size)
1755{
1756        int err;
1757        struct p9_req_t *req;
1758        struct p9_client *clnt;
1759        struct p9_fid *attr_fid;
1760
1761        err = 0;
1762        clnt = file_fid->clnt;
1763        attr_fid = p9_fid_create(clnt);
1764        if (IS_ERR(attr_fid)) {
1765                err = PTR_ERR(attr_fid);
1766                attr_fid = NULL;
1767                goto error;
1768        }
1769        P9_DPRINTK(P9_DEBUG_9P,
1770                ">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
1771                file_fid->fid, attr_fid->fid, attr_name);
1772
1773        req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
1774                        file_fid->fid, attr_fid->fid, attr_name);
1775        if (IS_ERR(req)) {
1776                err = PTR_ERR(req);
1777                goto error;
1778        }
1779        err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
1780        if (err) {
1781                P9_DUMP_PKT(1, req->rc);
1782                p9_free_req(clnt, req);
1783                goto clunk_fid;
1784        }
1785        p9_free_req(clnt, req);
1786        P9_DPRINTK(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
1787                attr_fid->fid, *attr_size);
1788        return attr_fid;
1789clunk_fid:
1790        p9_client_clunk(attr_fid);
1791        attr_fid = NULL;
1792error:
1793        if (attr_fid && (attr_fid != file_fid))
1794                p9_fid_destroy(attr_fid);
1795
1796        return ERR_PTR(err);
1797}
1798EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
1799
1800int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
1801                        u64 attr_size, int flags)
1802{
1803        int err;
1804        struct p9_req_t *req;
1805        struct p9_client *clnt;
1806
1807        P9_DPRINTK(P9_DEBUG_9P,
1808                ">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
1809                fid->fid, name, (long long)attr_size, flags);
1810        err = 0;
1811        clnt = fid->clnt;
1812        req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
1813                        fid->fid, name, attr_size, flags);
1814        if (IS_ERR(req)) {
1815                err = PTR_ERR(req);
1816                goto error;
1817        }
1818        P9_DPRINTK(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
1819        p9_free_req(clnt, req);
1820error:
1821        return err;
1822}
1823EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
1824
1825int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
1826{
1827        int err, rsize;
1828        struct p9_client *clnt;
1829        struct p9_req_t *req;
1830        char *dataptr;
1831
1832        P9_DPRINTK(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
1833                                fid->fid, (long long unsigned) offset, count);
1834
1835        err = 0;
1836        clnt = fid->clnt;
1837
1838        rsize = fid->iounit;
1839        if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
1840                rsize = clnt->msize - P9_READDIRHDRSZ;
1841
1842        if (count < rsize)
1843                rsize = count;
1844
1845        if ((clnt->trans_mod->pref & P9_TRANS_PREF_PAYLOAD_MASK) ==
1846                        P9_TRANS_PREF_PAYLOAD_SEP) {
1847                req = p9_client_rpc(clnt, P9_TREADDIR, "dqF", fid->fid,
1848                                offset, rsize, data);
1849        } else {
1850                req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
1851                                offset, rsize);
1852        }
1853        if (IS_ERR(req)) {
1854                err = PTR_ERR(req);
1855                goto error;
1856        }
1857
1858        err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1859        if (err) {
1860                P9_DUMP_PKT(1, req->rc);
1861                goto free_and_error;
1862        }
1863
1864        P9_DPRINTK(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
1865
1866        if (!req->tc->pbuf_size && data)
1867                memmove(data, dataptr, count);
1868
1869        p9_free_req(clnt, req);
1870        return count;
1871
1872free_and_error:
1873        p9_free_req(clnt, req);
1874error:
1875        return err;
1876}
1877EXPORT_SYMBOL(p9_client_readdir);
1878
1879int p9_client_mknod_dotl(struct p9_fid *fid, char *name, int mode,
1880                        dev_t rdev, gid_t gid, struct p9_qid *qid)
1881{
1882        int err;
1883        struct p9_client *clnt;
1884        struct p9_req_t *req;
1885
1886        err = 0;
1887        clnt = fid->clnt;
1888        P9_DPRINTK(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
1889                "minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
1890        req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddd", fid->fid, name, mode,
1891                MAJOR(rdev), MINOR(rdev), gid);
1892        if (IS_ERR(req))
1893                return PTR_ERR(req);
1894
1895        err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1896        if (err) {
1897                P9_DUMP_PKT(1, req->rc);
1898                goto error;
1899        }
1900        P9_DPRINTK(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
1901                                (unsigned long long)qid->path, qid->version);
1902
1903error:
1904        p9_free_req(clnt, req);
1905        return err;
1906
1907}
1908EXPORT_SYMBOL(p9_client_mknod_dotl);
1909
1910int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
1911                                gid_t gid, struct p9_qid *qid)
1912{
1913        int err;
1914        struct p9_client *clnt;
1915        struct p9_req_t *req;
1916
1917        err = 0;
1918        clnt = fid->clnt;
1919        P9_DPRINTK(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
1920                 fid->fid, name, mode, gid);
1921        req = p9_client_rpc(clnt, P9_TMKDIR, "dsdd", fid->fid, name, mode,
1922                gid);
1923        if (IS_ERR(req))
1924                return PTR_ERR(req);
1925
1926        err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1927        if (err) {
1928                P9_DUMP_PKT(1, req->rc);
1929                goto error;
1930        }
1931        P9_DPRINTK(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
1932                                (unsigned long long)qid->path, qid->version);
1933
1934error:
1935        p9_free_req(clnt, req);
1936        return err;
1937
1938}
1939EXPORT_SYMBOL(p9_client_mkdir_dotl);
1940
1941int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
1942{
1943        int err;
1944        struct p9_client *clnt;
1945        struct p9_req_t *req;
1946
1947        err = 0;
1948        clnt = fid->clnt;
1949        P9_DPRINTK(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
1950                        "start %lld length %lld proc_id %d client_id %s\n",
1951                        fid->fid, flock->type, flock->flags, flock->start,
1952                        flock->length, flock->proc_id, flock->client_id);
1953
1954        req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
1955                                flock->flags, flock->start, flock->length,
1956                                        flock->proc_id, flock->client_id);
1957
1958        if (IS_ERR(req))
1959                return PTR_ERR(req);
1960
1961        err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
1962        if (err) {
1963                P9_DUMP_PKT(1, req->rc);
1964                goto error;
1965        }
1966        P9_DPRINTK(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
1967error:
1968        p9_free_req(clnt, req);
1969        return err;
1970
1971}
1972EXPORT_SYMBOL(p9_client_lock_dotl);
1973
1974int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
1975{
1976        int err;
1977        struct p9_client *clnt;
1978        struct p9_req_t *req;
1979
1980        err = 0;
1981        clnt = fid->clnt;
1982        P9_DPRINTK(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
1983                "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
1984                glock->start, glock->length, glock->proc_id, glock->client_id);
1985
1986        req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
1987                glock->start, glock->length, glock->proc_id, glock->client_id);
1988
1989        if (IS_ERR(req))
1990                return PTR_ERR(req);
1991
1992        err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
1993                        &glock->start, &glock->length, &glock->proc_id,
1994                        &glock->client_id);
1995        if (err) {
1996                P9_DUMP_PKT(1, req->rc);
1997                goto error;
1998        }
1999        P9_DPRINTK(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2000                "proc_id %d client_id %s\n", glock->type, glock->start,
2001                glock->length, glock->proc_id, glock->client_id);
2002error:
2003        p9_free_req(clnt, req);
2004        return err;
2005}
2006EXPORT_SYMBOL(p9_client_getlock_dotl);
2007
2008int p9_client_readlink(struct p9_fid *fid, char **target)
2009{
2010        int err;
2011        struct p9_client *clnt;
2012        struct p9_req_t *req;
2013
2014        err = 0;
2015        clnt = fid->clnt;
2016        P9_DPRINTK(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2017
2018        req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2019        if (IS_ERR(req))
2020                return PTR_ERR(req);
2021
2022        err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2023        if (err) {
2024                P9_DUMP_PKT(1, req->rc);
2025                goto error;
2026        }
2027        P9_DPRINTK(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2028error:
2029        p9_free_req(clnt, req);
2030        return err;
2031}
2032EXPORT_SYMBOL(p9_client_readlink);
2033