net/9p/client.c

   1 /*
   2  * net/9p/clnt.c
   3  *
   4  * 9P Client
   5  *
   6  *  Copyright (C) 2008 by Eric Van Hensbergen <[email protected]>
   7  *  Copyright (C) 2007 by Latchesar Ionkov <[email protected]>
   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
  46 enum {
  47         Opt_msize,
  48         Opt_trans,
  49         Opt_legacy,
  50         Opt_version,
  51         Opt_err,
  52 };
  53
  54 static 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
  62 inline int p9_is_proto_dotl(struct p9_client *clnt)
  63 {
  64         return clnt->proto_version == p9_proto_2000L;
  65 }
  66 EXPORT_SYMBOL(p9_is_proto_dotl);
  67
  68 inline int p9_is_proto_dotu(struct p9_client *clnt)
  69 {
  70         return clnt->proto_version == p9_proto_2000u;
  71 }
  72 EXPORT_SYMBOL(p9_is_proto_dotu);
  73
  74 /* Interpret mount option for protocol version */
  75 static 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
 102 static 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
 186 free_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
 206 static 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
 294 struct 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 }
 310 EXPORT_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
 320 static 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;
 335 error:
 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  */
 346 static 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
 387 static 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  */
 403 void 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 }
 409 EXPORT_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
 420 int
 421 p9_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
 453 rewind_and_exit:
 454         if (rewind)
 455                 pdu->offset = offset;
 456         return err;
 457 }
 458 EXPORT_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
 471 static 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
 533 out_err:
 534         P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 535
 536         return err;
 537 }
 538
 539 static struct p9_req_t *
 540 p9_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
 554 static 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
 591 static struct p9_req_t *
 592 p9_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
 682 reterr:
 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
 689 static 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
 718 error:
 719         kfree(fid);
 720         return ERR_PTR(ret);
 721 }
 722
 723 static 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
 738 static 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
 791 error:
 792         kfree(version);
 793         p9_free_req(c, req);
 794
 795         return err;
 796 }
 797
 798 struct 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
 853 close_trans:
 854         clnt->trans_mod->close(clnt);
 855 destroy_fidpool:
 856         p9_idpool_destroy(clnt->fidpool);
 857 put_trans:
 858         v9fs_put_trans(clnt->trans_mod);
 859 destroy_tagpool:
 860         p9_idpool_destroy(clnt->tagpool);
 861 free_client:
 862         kfree(clnt);
 863         return ERR_PTR(err);
 864 }
 865 EXPORT_SYMBOL(p9_client_create);
 866
 867 void 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 }
 890 EXPORT_SYMBOL(p9_client_destroy);
 891
 892 void p9_client_disconnect(struct p9_client *clnt)
 893 {
 894         P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
 895         clnt->status = Disconnected;
 896 }
 897 EXPORT_SYMBOL(p9_client_disconnect);
 898
 899 void p9_client_begin_disconnect(struct p9_client *clnt)
 900 {
 901         P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
 902         clnt->status = BeginDisconnect;
 903 }
 904 EXPORT_SYMBOL(p9_client_begin_disconnect);
 905
 906 struct 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
 949 error:
 950         if (fid)
 951                 p9_fid_destroy(fid);
 952         return ERR_PTR(err);
 953 }
 954 EXPORT_SYMBOL(p9_client_attach);
 955
 956 struct 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
1021 clunk_fid:
1022         kfree(wqids);
1023         p9_client_clunk(fid);
1024         fid = NULL;
1025
1026 error:
1027         if (fid && (fid != oldfid))
1028                 p9_fid_destroy(fid);
1029
1030         return ERR_PTR(err);
1031 }
1032 EXPORT_SYMBOL(p9_client_walk);
1033
1034 int 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
1072 free_and_error:
1073         p9_free_req(clnt, req);
1074 error:
1075         return err;
1076 }
1077 EXPORT_SYMBOL(p9_client_open);
1078
1079 int 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
1116 free_and_error:
1117         p9_free_req(clnt, req);
1118 error:
1119         return err;
1120 }
1121 EXPORT_SYMBOL(p9_client_create_dotl);
1122
1123 int 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
1161 free_and_error:
1162         p9_free_req(clnt, req);
1163 error:
1164         return err;
1165 }
1166 EXPORT_SYMBOL(p9_client_fcreate);
1167
1168 int 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
1195 free_and_error:
1196         p9_free_req(clnt, req);
1197 error:
1198         return err;
1199 }
1200 EXPORT_SYMBOL(p9_client_symlink);
1201
1202 int 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 }
1219 EXPORT_SYMBOL(p9_client_link);
1220
1221 int 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
1242 error:
1243         return err;
1244 }
1245 EXPORT_SYMBOL(p9_client_fsync);
1246
1247 int 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);
1272 error:
1273         /*
1274          * Fid is not valid even after a failed clunk
1275          */
1276         p9_fid_destroy(fid);
1277         return err;
1278 }
1279 EXPORT_SYMBOL(p9_client_clunk);
1280
1281 int 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);
1300 error:
1301         p9_fid_destroy(fid);
1302         return err;
1303 }
1304 EXPORT_SYMBOL(p9_client_remove);
1305
1306 int 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);
1324 error:
1325         return err;
1326 }
1327 EXPORT_SYMBOL(p9_client_unlinkat);
1328
1329 int
1330 p9_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
1387 free_and_error:
1388         p9_free_req(clnt, req);
1389 error:
1390         return err;
1391 }
1392 EXPORT_SYMBOL(p9_client_read);
1393
1394 int
1395 p9_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
1444 free_and_error:
1445         p9_free_req(clnt, req);
1446 error:
1447         return err;
1448 }
1449 EXPORT_SYMBOL(p9_client_write);
1450
1451 struct 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
1494 error:
1495         kfree(ret);
1496         return ERR_PTR(err);
1497 }
1498 EXPORT_SYMBOL(p9_client_stat);
1499
1500 struct 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
1553 error:
1554         kfree(ret);
1555         return ERR_PTR(err);
1556 }
1557 EXPORT_SYMBOL(p9_client_getattr_dotl);
1558
1559 static 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
1588 int 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);
1618 error:
1619         return err;
1620 }
1621 EXPORT_SYMBOL(p9_client_wstat);
1622
1623 int 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);
1648 error:
1649         return err;
1650 }
1651 EXPORT_SYMBOL(p9_client_setattr);
1652
1653 int 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);
1687 error:
1688         return err;
1689 }
1690 EXPORT_SYMBOL(p9_client_statfs);
1691
1692 int 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);
1715 error:
1716         return err;
1717 }
1718 EXPORT_SYMBOL(p9_client_rename);
1719
1720 int 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);
1745 error:
1746         return err;
1747 }
1748 EXPORT_SYMBOL(p9_client_renameat);
1749
1750 /*
1751  * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1752  */
1753 struct 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;
1789 clunk_fid:
1790         p9_client_clunk(attr_fid);
1791         attr_fid = NULL;
1792 error:
1793         if (attr_fid && (attr_fid != file_fid))
1794                 p9_fid_destroy(attr_fid);
1795
1796         return ERR_PTR(err);
1797 }
1798 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
1799
1800 int 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);
1820 error:
1821         return err;
1822 }
1823 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
1824
1825 int 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
1872 free_and_error:
1873         p9_free_req(clnt, req);
1874 error:
1875         return err;
1876 }
1877 EXPORT_SYMBOL(p9_client_readdir);
1878
1879 int 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
1903 error:
1904         p9_free_req(clnt, req);
1905         return err;
1906
1907 }
1908 EXPORT_SYMBOL(p9_client_mknod_dotl);
1909
1910 int 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
1934 error:
1935         p9_free_req(clnt, req);
1936         return err;
1937
1938 }
1939 EXPORT_SYMBOL(p9_client_mkdir_dotl);
1940
1941 int 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);
1967 error:
1968         p9_free_req(clnt, req);
1969         return err;
1970
1971 }
1972 EXPORT_SYMBOL(p9_client_lock_dotl);
1973
1974 int 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);
2002 error:
2003         p9_free_req(clnt, req);
2004         return err;
2005 }
2006 EXPORT_SYMBOL(p9_client_getlock_dotl);
2007
2008 int 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);
2028 error:
2029         p9_free_req(clnt, req);
2030         return err;
2031 }
2032 EXPORT_SYMBOL(p9_client_readlink);