net/9p/client.c

   1 /*
   2  * net/9p/clnt.c
   3  *
   4  * 9P Client
   5  *
   6  *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
   7  *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License version 2
  11  *  as published by the Free Software Foundation.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to:
  20  *  Free Software Foundation
  21  *  51 Franklin Street, Fifth Floor
  22  *  Boston, MA  02111-1301  USA
  23  *
  24  */
  25
  26 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  27
  28 #include <linux/module.h>
  29 #include <linux/errno.h>
  30 #include <linux/fs.h>
  31 #include <linux/poll.h>
  32 #include <linux/idr.h>
  33 #include <linux/mutex.h>
  34 #include <linux/slab.h>
  35 #include <linux/sched.h>
  36 #include <linux/uaccess.h>
  37 #include <net/9p/9p.h>
  38 #include <linux/parser.h>
  39 #include <net/9p/client.h>
  40 #include <net/9p/transport.h>
  41 #include "protocol.h"
  42
  43 #define CREATE_TRACE_POINTS
  44 #include <trace/events/9p.h>
  45
  46 /*
  47   * Client Option Parsing (code inspired by NFS code)
  48   *  - a little lazy - parse all client options
  49   */
  50
  51 enum {
  52         Opt_msize,
  53         Opt_trans,
  54         Opt_legacy,
  55         Opt_version,
  56         Opt_err,
  57 };
  58
  59 static const match_table_t tokens = {
  60         {Opt_msize, "msize=%u"},
  61         {Opt_legacy, "noextend"},
  62         {Opt_trans, "trans=%s"},
  63         {Opt_version, "version=%s"},
  64         {Opt_err, NULL},
  65 };
  66
  67 inline int p9_is_proto_dotl(struct p9_client *clnt)
  68 {
  69         return clnt->proto_version == p9_proto_2000L;
  70 }
  71 EXPORT_SYMBOL(p9_is_proto_dotl);
  72
  73 inline int p9_is_proto_dotu(struct p9_client *clnt)
  74 {
  75         return clnt->proto_version == p9_proto_2000u;
  76 }
  77 EXPORT_SYMBOL(p9_is_proto_dotu);
  78
  79 /* Interpret mount option for protocol version */
  80 static int get_protocol_version(char *s)
  81 {
  82         int version = -EINVAL;
  83
  84         if (!strcmp(s, "9p2000")) {
  85                 version = p9_proto_legacy;
  86                 p9_debug(P9_DEBUG_9P, "Protocol version: Legacy\n");
  87         } else if (!strcmp(s, "9p2000.u")) {
  88                 version = p9_proto_2000u;
  89                 p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
  90         } else if (!strcmp(s, "9p2000.L")) {
  91                 version = p9_proto_2000L;
  92                 p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.L\n");
  93         } else
  94                 pr_info("Unknown protocol version %s\n", s);
  95
  96         return version;
  97 }
  98
  99 /**
 100  * parse_options - parse mount options into client structure
 101  * @opts: options string passed from mount
 102  * @clnt: existing v9fs client information
 103  *
 104  * Return 0 upon success, -ERRNO upon failure
 105  */
 106
 107 static int parse_opts(char *opts, struct p9_client *clnt)
 108 {
 109         char *options, *tmp_options;
 110         char *p;
 111         substring_t args[MAX_OPT_ARGS];
 112         int option;
 113         char *s;
 114         int ret = 0;
 115
 116         clnt->proto_version = p9_proto_2000u;
 117         clnt->msize = 8192;
 118
 119         if (!opts)
 120                 return 0;
 121
 122         tmp_options = kstrdup(opts, GFP_KERNEL);
 123         if (!tmp_options) {
 124                 p9_debug(P9_DEBUG_ERROR,
 125                          "failed to allocate copy of option string\n");
 126                 return -ENOMEM;
 127         }
 128         options = tmp_options;
 129
 130         while ((p = strsep(&options, ",")) != NULL) {
 131                 int token, r;
 132                 if (!*p)
 133                         continue;
 134                 token = match_token(p, tokens, args);
 135                 switch (token) {
 136                 case Opt_msize:
 137                         r = match_int(&args[0], &option);
 138                         if (r < 0) {
 139                                 p9_debug(P9_DEBUG_ERROR,
 140                                          "integer field, but no integer?\n");
 141                                 ret = r;
 142                                 continue;
 143                         }
 144                         clnt->msize = option;
 145                         break;
 146                 case Opt_trans:
 147                         s = match_strdup(&args[0]);
 148                         if (!s) {
 149                                 ret = -ENOMEM;
 150                                 p9_debug(P9_DEBUG_ERROR,
 151                                          "problem allocating copy of trans arg\n");
 152                                 goto free_and_return;
 153                          }
 154                         clnt->trans_mod = v9fs_get_trans_by_name(s);
 155                         if (clnt->trans_mod == NULL) {
 156                                 pr_info("Could not find request transport: %s\n",
 157                                         s);
 158                                 ret = -EINVAL;
 159                                 kfree(s);
 160                                 goto free_and_return;
 161                         }
 162                         kfree(s);
 163                         break;
 164                 case Opt_legacy:
 165                         clnt->proto_version = p9_proto_legacy;
 166                         break;
 167                 case Opt_version:
 168                         s = match_strdup(&args[0]);
 169                         if (!s) {
 170                                 ret = -ENOMEM;
 171                                 p9_debug(P9_DEBUG_ERROR,
 172                                          "problem allocating copy of version arg\n");
 173                                 goto free_and_return;
 174                         }
 175                         ret = get_protocol_version(s);
 176                         if (ret == -EINVAL) {
 177                                 kfree(s);
 178                                 goto free_and_return;
 179                         }
 180                         kfree(s);
 181                         clnt->proto_version = ret;
 182                         break;
 183                 default:
 184                         continue;
 185                 }
 186         }
 187
 188 free_and_return:
 189         kfree(tmp_options);
 190         return ret;
 191 }
 192
 193 /**
 194  * p9_tag_alloc - lookup/allocate a request by tag
 195  * @c: client session to lookup tag within
 196  * @tag: numeric id for transaction
 197  *
 198  * this is a simple array lookup, but will grow the
 199  * request_slots as necessary to accommodate transaction
 200  * ids which did not previously have a slot.
 201  *
 202  * this code relies on the client spinlock to manage locks, its
 203  * possible we should switch to something else, but I'd rather
 204  * stick with something low-overhead for the common case.
 205  *
 206  */
 207
 208 static struct p9_req_t *
 209 p9_tag_alloc(struct p9_client *c, u16 tag, unsigned int max_size)
 210 {
 211         unsigned long flags;
 212         int row, col;
 213         struct p9_req_t *req;
 214         int alloc_msize = min(c->msize, max_size);
 215
 216         /* This looks up the original request by tag so we know which
 217          * buffer to read the data into */
 218         tag++;
 219
 220         if (tag >= c->max_tag) {
 221                 spin_lock_irqsave(&c->lock, flags);
 222                 /* check again since original check was outside of lock */
 223                 while (tag >= c->max_tag) {
 224                         row = (tag / P9_ROW_MAXTAG);
 225                         c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
 226                                         sizeof(struct p9_req_t), GFP_ATOMIC);
 227
 228                         if (!c->reqs[row]) {
 229                                 pr_err("Couldn't grow tag array\n");
 230                                 spin_unlock_irqrestore(&c->lock, flags);
 231                                 return ERR_PTR(-ENOMEM);
 232                         }
 233                         for (col = 0; col < P9_ROW_MAXTAG; col++) {
 234                                 c->reqs[row][col].status = REQ_STATUS_IDLE;
 235                                 c->reqs[row][col].tc = NULL;
 236                         }
 237                         c->max_tag += P9_ROW_MAXTAG;
 238                 }
 239                 spin_unlock_irqrestore(&c->lock, flags);
 240         }
 241         row = tag / P9_ROW_MAXTAG;
 242         col = tag % P9_ROW_MAXTAG;
 243
 244         req = &c->reqs[row][col];
 245         if (!req->tc) {
 246                 req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_NOFS);
 247                 if (!req->wq) {
 248                         pr_err("Couldn't grow tag array\n");
 249                         return ERR_PTR(-ENOMEM);
 250                 }
 251                 init_waitqueue_head(req->wq);
 252                 req->tc = kmalloc(sizeof(struct p9_fcall) + alloc_msize,
 253                                   GFP_NOFS);
 254                 req->rc = kmalloc(sizeof(struct p9_fcall) + alloc_msize,
 255                                   GFP_NOFS);
 256                 if ((!req->tc) || (!req->rc)) {
 257                         pr_err("Couldn't grow tag array\n");
 258                         kfree(req->tc);
 259                         kfree(req->rc);
 260                         kfree(req->wq);
 261                         req->tc = req->rc = NULL;
 262                         req->wq = NULL;
 263                         return ERR_PTR(-ENOMEM);
 264                 }
 265                 req->tc->capacity = alloc_msize;
 266                 req->rc->capacity = alloc_msize;
 267                 req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
 268                 req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall);
 269         }
 270
 271         p9pdu_reset(req->tc);
 272         p9pdu_reset(req->rc);
 273
 274         req->tc->tag = tag-1;
 275         req->status = REQ_STATUS_ALLOC;
 276
 277         return &c->reqs[row][col];
 278 }
 279
 280 /**
 281  * p9_tag_lookup - lookup a request by tag
 282  * @c: client session to lookup tag within
 283  * @tag: numeric id for transaction
 284  *
 285  */
 286
 287 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
 288 {
 289         int row, col;
 290
 291         /* This looks up the original request by tag so we know which
 292          * buffer to read the data into */
 293         tag++;
 294
 295         if(tag >= c->max_tag)
 296                 return NULL;
 297
 298         row = tag / P9_ROW_MAXTAG;
 299         col = tag % P9_ROW_MAXTAG;
 300
 301         return &c->reqs[row][col];
 302 }
 303 EXPORT_SYMBOL(p9_tag_lookup);
 304
 305 /**
 306  * p9_tag_init - setup tags structure and contents
 307  * @c:  v9fs client struct
 308  *
 309  * This initializes the tags structure for each client instance.
 310  *
 311  */
 312
 313 static int p9_tag_init(struct p9_client *c)
 314 {
 315         int err = 0;
 316
 317         c->tagpool = p9_idpool_create();
 318         if (IS_ERR(c->tagpool)) {
 319                 err = PTR_ERR(c->tagpool);
 320                 goto error;
 321         }
 322         err = p9_idpool_get(c->tagpool); /* reserve tag 0 */
 323         if (err < 0) {
 324                 p9_idpool_destroy(c->tagpool);
 325                 goto error;
 326         }
 327         c->max_tag = 0;
 328 error:
 329         return err;
 330 }
 331
 332 /**
 333  * p9_tag_cleanup - cleans up tags structure and reclaims resources
 334  * @c:  v9fs client struct
 335  *
 336  * This frees resources associated with the tags structure
 337  *
 338  */
 339 static void p9_tag_cleanup(struct p9_client *c)
 340 {
 341         int row, col;
 342
 343         /* check to insure all requests are idle */
 344         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 345                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 346                         if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
 347                                 p9_debug(P9_DEBUG_MUX,
 348                                          "Attempting to cleanup non-free tag %d,%d\n",
 349                                          row, col);
 350                                 /* TODO: delay execution of cleanup */
 351                                 return;
 352                         }
 353                 }
 354         }
 355
 356         if (c->tagpool) {
 357                 p9_idpool_put(0, c->tagpool); /* free reserved tag 0 */
 358                 p9_idpool_destroy(c->tagpool);
 359         }
 360
 361         /* free requests associated with tags */
 362         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 363                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 364                         kfree(c->reqs[row][col].wq);
 365                         kfree(c->reqs[row][col].tc);
 366                         kfree(c->reqs[row][col].rc);
 367                 }
 368                 kfree(c->reqs[row]);
 369         }
 370         c->max_tag = 0;
 371 }
 372
 373 /**
 374  * p9_free_req - free a request and clean-up as necessary
 375  * c: client state
 376  * r: request to release
 377  *
 378  */
 379
 380 static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
 381 {
 382         int tag = r->tc->tag;
 383         p9_debug(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
 384
 385         r->status = REQ_STATUS_IDLE;
 386         if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
 387                 p9_idpool_put(tag, c->tagpool);
 388 }
 389
 390 /**
 391  * p9_client_cb - call back from transport to client
 392  * c: client state
 393  * req: request received
 394  *
 395  */
 396 void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
 397 {
 398         p9_debug(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
 399         wake_up(req->wq);
 400         p9_debug(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
 401 }
 402 EXPORT_SYMBOL(p9_client_cb);
 403
 404 /**
 405  * p9_parse_header - parse header arguments out of a packet
 406  * @pdu: packet to parse
 407  * @size: size of packet
 408  * @type: type of request
 409  * @tag: tag of packet
 410  * @rewind: set if we need to rewind offset afterwards
 411  */
 412
 413 int
 414 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
 415                                                                 int rewind)
 416 {
 417         int8_t r_type;
 418         int16_t r_tag;
 419         int32_t r_size;
 420         int offset = pdu->offset;
 421         int err;
 422
 423         pdu->offset = 0;
 424         if (pdu->size == 0)
 425                 pdu->size = 7;
 426
 427         err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
 428         if (err)
 429                 goto rewind_and_exit;
 430
 431         pdu->size = r_size;
 432         pdu->id = r_type;
 433         pdu->tag = r_tag;
 434
 435         p9_debug(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n",
 436                  pdu->size, pdu->id, pdu->tag);
 437
 438         if (type)
 439                 *type = r_type;
 440         if (tag)
 441                 *tag = r_tag;
 442         if (size)
 443                 *size = r_size;
 444
 445
 446 rewind_and_exit:
 447         if (rewind)
 448                 pdu->offset = offset;
 449         return err;
 450 }
 451 EXPORT_SYMBOL(p9_parse_header);
 452
 453 /**
 454  * p9_check_errors - check 9p packet for error return and process it
 455  * @c: current client instance
 456  * @req: request to parse and check for error conditions
 457  *
 458  * returns error code if one is discovered, otherwise returns 0
 459  *
 460  * this will have to be more complicated if we have multiple
 461  * error packet types
 462  */
 463
 464 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 465 {
 466         int8_t type;
 467         int err;
 468         int ecode;
 469
 470         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 471         /*
 472          * dump the response from server
 473          * This should be after check errors which poplulate pdu_fcall.
 474          */
 475         trace_9p_protocol_dump(c, req->rc);
 476         if (err) {
 477                 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 478                 return err;
 479         }
 480         if (type != P9_RERROR && type != P9_RLERROR)
 481                 return 0;
 482
 483         if (!p9_is_proto_dotl(c)) {
 484                 char *ename;
 485                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 486                                   &ename, &ecode);
 487                 if (err)
 488                         goto out_err;
 489
 490                 if (p9_is_proto_dotu(c))
 491                         err = -ecode;
 492
 493                 if (!err || !IS_ERR_VALUE(err)) {
 494                         err = p9_errstr2errno(ename, strlen(ename));
 495
 496                         p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 497                                  -ecode, ename);
 498                 }
 499                 kfree(ename);
 500         } else {
 501                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 502                 err = -ecode;
 503
 504                 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 505         }
 506
 507         return err;
 508
 509 out_err:
 510         p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 511
 512         return err;
 513 }
 514
 515 /**
 516  * p9_check_zc_errors - check 9p packet for error return and process it
 517  * @c: current client instance
 518  * @req: request to parse and check for error conditions
 519  * @in_hdrlen: Size of response protocol buffer.
 520  *
 521  * returns error code if one is discovered, otherwise returns 0
 522  *
 523  * this will have to be more complicated if we have multiple
 524  * error packet types
 525  */
 526
 527 static int p9_check_zc_errors(struct p9_client *c, struct p9_req_t *req,
 528                               char *uidata, int in_hdrlen, int kern_buf)
 529 {
 530         int err;
 531         int ecode;
 532         int8_t type;
 533         char *ename = NULL;
 534
 535         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 536         /*
 537          * dump the response from server
 538          * This should be after parse_header which poplulate pdu_fcall.
 539          */
 540         trace_9p_protocol_dump(c, req->rc);
 541         if (err) {
 542                 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 543                 return err;
 544         }
 545
 546         if (type != P9_RERROR && type != P9_RLERROR)
 547                 return 0;
 548
 549         if (!p9_is_proto_dotl(c)) {
 550                 /* Error is reported in string format */
 551                 uint16_t len;
 552                 /* 7 = header size for RERROR, 2 is the size of string len; */
 553                 int inline_len = in_hdrlen - (7 + 2);
 554
 555                 /* Read the size of error string */
 556                 err = p9pdu_readf(req->rc, c->proto_version, "w", &len);
 557                 if (err)
 558                         goto out_err;
 559
 560                 ename = kmalloc(len + 1, GFP_NOFS);
 561                 if (!ename) {
 562                         err = -ENOMEM;
 563                         goto out_err;
 564                 }
 565                 if (len <= inline_len) {
 566                         /* We have error in protocol buffer itself */
 567                         if (pdu_read(req->rc, ename, len)) {
 568                                 err = -EFAULT;
 569                                 goto out_free;
 570
 571                         }
 572                 } else {
 573                         /*
 574                          *  Part of the data is in user space buffer.
 575                          */
 576                         if (pdu_read(req->rc, ename, inline_len)) {
 577                                 err = -EFAULT;
 578                                 goto out_free;
 579
 580                         }
 581                         if (kern_buf) {
 582                                 memcpy(ename + inline_len, uidata,
 583                                        len - inline_len);
 584                         } else {
 585                                 err = copy_from_user(ename + inline_len,
 586                                                      uidata, len - inline_len);
 587                                 if (err) {
 588                                         err = -EFAULT;
 589                                         goto out_free;
 590                                 }
 591                         }
 592                 }
 593                 ename[len] = 0;
 594                 if (p9_is_proto_dotu(c)) {
 595                         /* For dotu we also have error code */
 596                         err = p9pdu_readf(req->rc,
 597                                           c->proto_version, "d", &ecode);
 598                         if (err)
 599                                 goto out_free;
 600                         err = -ecode;
 601                 }
 602                 if (!err || !IS_ERR_VALUE(err)) {
 603                         err = p9_errstr2errno(ename, strlen(ename));
 604
 605                         p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 606                                  -ecode, ename);
 607                 }
 608                 kfree(ename);
 609         } else {
 610                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 611                 err = -ecode;
 612
 613                 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 614         }
 615         return err;
 616
 617 out_free:
 618         kfree(ename);
 619 out_err:
 620         p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 621         return err;
 622 }
 623
 624 static struct p9_req_t *
 625 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
 626
 627 /**
 628  * p9_client_flush - flush (cancel) a request
 629  * @c: client state
 630  * @oldreq: request to cancel
 631  *
 632  * This sents a flush for a particular request and links
 633  * the flush request to the original request.  The current
 634  * code only supports a single flush request although the protocol
 635  * allows for multiple flush requests to be sent for a single request.
 636  *
 637  */
 638
 639 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 640 {
 641         struct p9_req_t *req;
 642         int16_t oldtag;
 643         int err;
 644
 645         err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
 646         if (err)
 647                 return err;
 648
 649         p9_debug(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
 650
 651         req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
 652         if (IS_ERR(req))
 653                 return PTR_ERR(req);
 654
 655
 656         /* if we haven't received a response for oldreq,
 657            remove it from the list. */
 658         spin_lock(&c->lock);
 659         if (oldreq->status == REQ_STATUS_FLSH)
 660                 list_del(&oldreq->req_list);
 661         spin_unlock(&c->lock);
 662
 663         p9_free_req(c, req);
 664         return 0;
 665 }
 666
 667 static struct p9_req_t *p9_client_prepare_req(struct p9_client *c,
 668                                               int8_t type, int req_size,
 669                                               const char *fmt, va_list ap)
 670 {
 671         int tag, err;
 672         struct p9_req_t *req;
 673
 674         p9_debug(P9_DEBUG_MUX, "client %p op %d\n", c, type);
 675
 676         /* we allow for any status other than disconnected */
 677         if (c->status == Disconnected)
 678                 return ERR_PTR(-EIO);
 679
 680         /* if status is begin_disconnected we allow only clunk request */
 681         if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
 682                 return ERR_PTR(-EIO);
 683
 684         tag = P9_NOTAG;
 685         if (type != P9_TVERSION) {
 686                 tag = p9_idpool_get(c->tagpool);
 687                 if (tag < 0)
 688                         return ERR_PTR(-ENOMEM);
 689         }
 690
 691         req = p9_tag_alloc(c, tag, req_size);
 692         if (IS_ERR(req))
 693                 return req;
 694
 695         /* marshall the data */
 696         p9pdu_prepare(req->tc, tag, type);
 697         err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
 698         if (err)
 699                 goto reterr;
 700         p9pdu_finalize(c, req->tc);
 701         trace_9p_client_req(c, type, tag);
 702         return req;
 703 reterr:
 704         p9_free_req(c, req);
 705         return ERR_PTR(err);
 706 }
 707
 708 /**
 709  * p9_client_rpc - issue a request and wait for a response
 710  * @c: client session
 711  * @type: type of request
 712  * @fmt: protocol format string (see protocol.c)
 713  *
 714  * Returns request structure (which client must free using p9_free_req)
 715  */
 716
 717 static struct p9_req_t *
 718 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 719 {
 720         va_list ap;
 721         int sigpending, err;
 722         unsigned long flags;
 723         struct p9_req_t *req;
 724
 725         va_start(ap, fmt);
 726         req = p9_client_prepare_req(c, type, c->msize, fmt, ap);
 727         va_end(ap);
 728         if (IS_ERR(req))
 729                 return req;
 730
 731         if (signal_pending(current)) {
 732                 sigpending = 1;
 733                 clear_thread_flag(TIF_SIGPENDING);
 734         } else
 735                 sigpending = 0;
 736
 737         err = c->trans_mod->request(c, req);
 738         if (err < 0) {
 739                 if (err != -ERESTARTSYS && err != -EFAULT)
 740                         c->status = Disconnected;
 741                 goto reterr;
 742         }
 743         /* Wait for the response */
 744         err = wait_event_interruptible(*req->wq,
 745                                        req->status >= REQ_STATUS_RCVD);
 746
 747         if (req->status == REQ_STATUS_ERROR) {
 748                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 749                 err = req->t_err;
 750         }
 751         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 752                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 753                 sigpending = 1;
 754                 clear_thread_flag(TIF_SIGPENDING);
 755
 756                 if (c->trans_mod->cancel(c, req))
 757                         p9_client_flush(c, req);
 758
 759                 /* if we received the response anyway, don't signal error */
 760                 if (req->status == REQ_STATUS_RCVD)
 761                         err = 0;
 762         }
 763         if (sigpending) {
 764                 spin_lock_irqsave(&current->sighand->siglock, flags);
 765                 recalc_sigpending();
 766                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 767         }
 768         if (err < 0)
 769                 goto reterr;
 770
 771         err = p9_check_errors(c, req);
 772         trace_9p_client_res(c, type, req->rc->tag, err);
 773         if (!err)
 774                 return req;
 775 reterr:
 776         p9_free_req(c, req);
 777         return ERR_PTR(err);
 778 }
 779
 780 /**
 781  * p9_client_zc_rpc - issue a request and wait for a response
 782  * @c: client session
 783  * @type: type of request
 784  * @uidata: user bffer that should be ued for zero copy read
 785  * @uodata: user buffer that shoud be user for zero copy write
 786  * @inlen: read buffer size
 787  * @olen: write buffer size
 788  * @hdrlen: reader header size, This is the size of response protocol data
 789  * @fmt: protocol format string (see protocol.c)
 790  *
 791  * Returns request structure (which client must free using p9_free_req)
 792  */
 793 static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
 794                                          char *uidata, char *uodata,
 795                                          int inlen, int olen, int in_hdrlen,
 796                                          int kern_buf, const char *fmt, ...)
 797 {
 798         va_list ap;
 799         int sigpending, err;
 800         unsigned long flags;
 801         struct p9_req_t *req;
 802
 803         va_start(ap, fmt);
 804         /*
 805          * We allocate a inline protocol data of only 4k bytes.
 806          * The actual content is passed in zero-copy fashion.
 807          */
 808         req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, fmt, ap);
 809         va_end(ap);
 810         if (IS_ERR(req))
 811                 return req;
 812
 813         if (signal_pending(current)) {
 814                 sigpending = 1;
 815                 clear_thread_flag(TIF_SIGPENDING);
 816         } else
 817                 sigpending = 0;
 818
 819         /* If we are called with KERNEL_DS force kern_buf */
 820         if (segment_eq(get_fs(), KERNEL_DS))
 821                 kern_buf = 1;
 822
 823         err = c->trans_mod->zc_request(c, req, uidata, uodata,
 824                                        inlen, olen, in_hdrlen, kern_buf);
 825         if (err < 0) {
 826                 if (err == -EIO)
 827                         c->status = Disconnected;
 828                 goto reterr;
 829         }
 830         if (req->status == REQ_STATUS_ERROR) {
 831                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 832                 err = req->t_err;
 833         }
 834         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 835                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 836                 sigpending = 1;
 837                 clear_thread_flag(TIF_SIGPENDING);
 838
 839                 if (c->trans_mod->cancel(c, req))
 840                         p9_client_flush(c, req);
 841
 842                 /* if we received the response anyway, don't signal error */
 843                 if (req->status == REQ_STATUS_RCVD)
 844                         err = 0;
 845         }
 846         if (sigpending) {
 847                 spin_lock_irqsave(&current->sighand->siglock, flags);
 848                 recalc_sigpending();
 849                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 850         }
 851         if (err < 0)
 852                 goto reterr;
 853
 854         err = p9_check_zc_errors(c, req, uidata, in_hdrlen, kern_buf);
 855         trace_9p_client_res(c, type, req->rc->tag, err);
 856         if (!err)
 857                 return req;
 858 reterr:
 859         p9_free_req(c, req);
 860         return ERR_PTR(err);
 861 }
 862
 863 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 864 {
 865         int ret;
 866         struct p9_fid *fid;
 867         unsigned long flags;
 868
 869         p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt);
 870         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
 871         if (!fid)
 872                 return ERR_PTR(-ENOMEM);
 873
 874         ret = p9_idpool_get(clnt->fidpool);
 875         if (ret < 0) {
 876                 ret = -ENOSPC;
 877                 goto error;
 878         }
 879         fid->fid = ret;
 880
 881         memset(&fid->qid, 0, sizeof(struct p9_qid));
 882         fid->mode = -1;
 883         fid->uid = current_fsuid();
 884         fid->clnt = clnt;
 885         fid->rdir = NULL;
 886         spin_lock_irqsave(&clnt->lock, flags);
 887         list_add(&fid->flist, &clnt->fidlist);
 888         spin_unlock_irqrestore(&clnt->lock, flags);
 889
 890         return fid;
 891
 892 error:
 893         kfree(fid);
 894         return ERR_PTR(ret);
 895 }
 896
 897 static void p9_fid_destroy(struct p9_fid *fid)
 898 {
 899         struct p9_client *clnt;
 900         unsigned long flags;
 901
 902         p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
 903         clnt = fid->clnt;
 904         p9_idpool_put(fid->fid, clnt->fidpool);
 905         spin_lock_irqsave(&clnt->lock, flags);
 906         list_del(&fid->flist);
 907         spin_unlock_irqrestore(&clnt->lock, flags);
 908         kfree(fid->rdir);
 909         kfree(fid);
 910 }
 911
 912 static int p9_client_version(struct p9_client *c)
 913 {
 914         int err = 0;
 915         struct p9_req_t *req;
 916         char *version;
 917         int msize;
 918
 919         p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
 920                  c->msize, c->proto_version);
 921
 922         switch (c->proto_version) {
 923         case p9_proto_2000L:
 924                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 925                                         c->msize, "9P2000.L");
 926                 break;
 927         case p9_proto_2000u:
 928                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 929                                         c->msize, "9P2000.u");
 930                 break;
 931         case p9_proto_legacy:
 932                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 933                                         c->msize, "9P2000");
 934                 break;
 935         default:
 936                 return -EINVAL;
 937                 break;
 938         }
 939
 940         if (IS_ERR(req))
 941                 return PTR_ERR(req);
 942
 943         err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
 944         if (err) {
 945                 p9_debug(P9_DEBUG_9P, "version error %d\n", err);
 946                 trace_9p_protocol_dump(c, req->rc);
 947                 goto error;
 948         }
 949
 950         p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
 951         if (!strncmp(version, "9P2000.L", 8))
 952                 c->proto_version = p9_proto_2000L;
 953         else if (!strncmp(version, "9P2000.u", 8))
 954                 c->proto_version = p9_proto_2000u;
 955         else if (!strncmp(version, "9P2000", 6))
 956                 c->proto_version = p9_proto_legacy;
 957         else {
 958                 err = -EREMOTEIO;
 959                 goto error;
 960         }
 961
 962         if (msize < c->msize)
 963                 c->msize = msize;
 964
 965 error:
 966         kfree(version);
 967         p9_free_req(c, req);
 968
 969         return err;
 970 }
 971
 972 struct p9_client *p9_client_create(const char *dev_name, char *options)
 973 {
 974         int err;
 975         struct p9_client *clnt;
 976
 977         err = 0;
 978         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
 979         if (!clnt)
 980                 return ERR_PTR(-ENOMEM);
 981
 982         clnt->trans_mod = NULL;
 983         clnt->trans = NULL;
 984         spin_lock_init(&clnt->lock);
 985         INIT_LIST_HEAD(&clnt->fidlist);
 986
 987         err = p9_tag_init(clnt);
 988         if (err < 0)
 989                 goto free_client;
 990
 991         err = parse_opts(options, clnt);
 992         if (err < 0)
 993                 goto destroy_tagpool;
 994
 995         if (!clnt->trans_mod)
 996                 clnt->trans_mod = v9fs_get_default_trans();
 997
 998         if (clnt->trans_mod == NULL) {
 999                 err = -EPROTONOSUPPORT;
1000                 p9_debug(P9_DEBUG_ERROR,
1001                          "No transport defined or default transport\n");
1002                 goto destroy_tagpool;
1003         }
1004
1005         clnt->fidpool = p9_idpool_create();
1006         if (IS_ERR(clnt->fidpool)) {
1007                 err = PTR_ERR(clnt->fidpool);
1008                 goto put_trans;
1009         }
1010
1011         p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1012                  clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1013
1014         err = clnt->trans_mod->create(clnt, dev_name, options);
1015         if (err)
1016                 goto destroy_fidpool;
1017
1018         if (clnt->msize > clnt->trans_mod->maxsize)
1019                 clnt->msize = clnt->trans_mod->maxsize;
1020
1021         err = p9_client_version(clnt);
1022         if (err)
1023                 goto close_trans;
1024
1025         return clnt;
1026
1027 close_trans:
1028         clnt->trans_mod->close(clnt);
1029 destroy_fidpool:
1030         p9_idpool_destroy(clnt->fidpool);
1031 put_trans:
1032         v9fs_put_trans(clnt->trans_mod);
1033 destroy_tagpool:
1034         p9_idpool_destroy(clnt->tagpool);
1035 free_client:
1036         kfree(clnt);
1037         return ERR_PTR(err);
1038 }
1039 EXPORT_SYMBOL(p9_client_create);
1040
1041 void p9_client_destroy(struct p9_client *clnt)
1042 {
1043         struct p9_fid *fid, *fidptr;
1044
1045         p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
1046
1047         if (clnt->trans_mod)
1048                 clnt->trans_mod->close(clnt);
1049
1050         v9fs_put_trans(clnt->trans_mod);
1051
1052         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
1053                 pr_info("Found fid %d not clunked\n", fid->fid);
1054                 p9_fid_destroy(fid);
1055         }
1056
1057         if (clnt->fidpool)
1058                 p9_idpool_destroy(clnt->fidpool);
1059
1060         p9_tag_cleanup(clnt);
1061
1062         kfree(clnt);
1063 }
1064 EXPORT_SYMBOL(p9_client_destroy);
1065
1066 void p9_client_disconnect(struct p9_client *clnt)
1067 {
1068         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1069         clnt->status = Disconnected;
1070 }
1071 EXPORT_SYMBOL(p9_client_disconnect);
1072
1073 void p9_client_begin_disconnect(struct p9_client *clnt)
1074 {
1075         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1076         clnt->status = BeginDisconnect;
1077 }
1078 EXPORT_SYMBOL(p9_client_begin_disconnect);
1079
1080 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1081         char *uname, u32 n_uname, char *aname)
1082 {
1083         int err = 0;
1084         struct p9_req_t *req;
1085         struct p9_fid *fid;
1086         struct p9_qid qid;
1087
1088
1089         p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1090                  afid ? afid->fid : -1, uname, aname);
1091         fid = p9_fid_create(clnt);
1092         if (IS_ERR(fid)) {
1093                 err = PTR_ERR(fid);
1094                 fid = NULL;
1095                 goto error;
1096         }
1097
1098         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
1099                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1100         if (IS_ERR(req)) {
1101                 err = PTR_ERR(req);
1102                 goto error;
1103         }
1104
1105         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
1106         if (err) {
1107                 trace_9p_protocol_dump(clnt, req->rc);
1108                 p9_free_req(clnt, req);
1109                 goto error;
1110         }
1111
1112         p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1113                  qid.type, (unsigned long long)qid.path, qid.version);
1114
1115         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1116
1117         p9_free_req(clnt, req);
1118         return fid;
1119
1120 error:
1121         if (fid)
1122                 p9_fid_destroy(fid);
1123         return ERR_PTR(err);
1124 }
1125 EXPORT_SYMBOL(p9_client_attach);
1126
1127 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1128                 char **wnames, int clone)
1129 {
1130         int err;
1131         struct p9_client *clnt;
1132         struct p9_fid *fid;
1133         struct p9_qid *wqids;
1134         struct p9_req_t *req;
1135         uint16_t nwqids, count;
1136
1137         err = 0;
1138         wqids = NULL;
1139         clnt = oldfid->clnt;
1140         if (clone) {
1141                 fid = p9_fid_create(clnt);
1142                 if (IS_ERR(fid)) {
1143                         err = PTR_ERR(fid);
1144                         fid = NULL;
1145                         goto error;
1146                 }
1147
1148                 fid->uid = oldfid->uid;
1149         } else
1150                 fid = oldfid;
1151
1152
1153         p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1154                  oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1155
1156         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1157                                                                 nwname, wnames);
1158         if (IS_ERR(req)) {
1159                 err = PTR_ERR(req);
1160                 goto error;
1161         }
1162
1163         err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1164         if (err) {
1165                 trace_9p_protocol_dump(clnt, req->rc);
1166                 p9_free_req(clnt, req);
1167                 goto clunk_fid;
1168         }
1169         p9_free_req(clnt, req);
1170
1171         p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1172
1173         if (nwqids != nwname) {
1174                 err = -ENOENT;
1175                 goto clunk_fid;
1176         }
1177
1178         for (count = 0; count < nwqids; count++)
1179                 p9_debug(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
1180                         count, wqids[count].type,
1181                         (unsigned long long)wqids[count].path,
1182                         wqids[count].version);
1183
1184         if (nwname)
1185                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1186         else
1187                 fid->qid = oldfid->qid;
1188
1189         kfree(wqids);
1190         return fid;
1191
1192 clunk_fid:
1193         kfree(wqids);
1194         p9_client_clunk(fid);
1195         fid = NULL;
1196
1197 error:
1198         if (fid && (fid != oldfid))
1199                 p9_fid_destroy(fid);
1200
1201         return ERR_PTR(err);
1202 }
1203 EXPORT_SYMBOL(p9_client_walk);
1204
1205 int p9_client_open(struct p9_fid *fid, int mode)
1206 {
1207         int err;
1208         struct p9_client *clnt;
1209         struct p9_req_t *req;
1210         struct p9_qid qid;
1211         int iounit;
1212
1213         clnt = fid->clnt;
1214         p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1215                 p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1216         err = 0;
1217
1218         if (fid->mode != -1)
1219                 return -EINVAL;
1220
1221         if (p9_is_proto_dotl(clnt))
1222                 req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1223         else
1224                 req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1225         if (IS_ERR(req)) {
1226                 err = PTR_ERR(req);
1227                 goto error;
1228         }
1229
1230         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1231         if (err) {
1232                 trace_9p_protocol_dump(clnt, req->rc);
1233                 goto free_and_error;
1234         }
1235
1236         p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1237                 p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1238                 (unsigned long long)qid.path, qid.version, iounit);
1239
1240         fid->mode = mode;
1241         fid->iounit = iounit;
1242
1243 free_and_error:
1244         p9_free_req(clnt, req);
1245 error:
1246         return err;
1247 }
1248 EXPORT_SYMBOL(p9_client_open);
1249
1250 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
1251                 gid_t gid, struct p9_qid *qid)
1252 {
1253         int err = 0;
1254         struct p9_client *clnt;
1255         struct p9_req_t *req;
1256         int iounit;
1257
1258         p9_debug(P9_DEBUG_9P,
1259                         ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1260                         ofid->fid, name, flags, mode, gid);
1261         clnt = ofid->clnt;
1262
1263         if (ofid->mode != -1)
1264                 return -EINVAL;
1265
1266         req = p9_client_rpc(clnt, P9_TLCREATE, "dsddd", ofid->fid, name, flags,
1267                         mode, gid);
1268         if (IS_ERR(req)) {
1269                 err = PTR_ERR(req);
1270                 goto error;
1271         }
1272
1273         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1274         if (err) {
1275                 trace_9p_protocol_dump(clnt, req->rc);
1276                 goto free_and_error;
1277         }
1278
1279         p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1280                         qid->type,
1281                         (unsigned long long)qid->path,
1282                         qid->version, iounit);
1283
1284         ofid->mode = mode;
1285         ofid->iounit = iounit;
1286
1287 free_and_error:
1288         p9_free_req(clnt, req);
1289 error:
1290         return err;
1291 }
1292 EXPORT_SYMBOL(p9_client_create_dotl);
1293
1294 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1295                      char *extension)
1296 {
1297         int err;
1298         struct p9_client *clnt;
1299         struct p9_req_t *req;
1300         struct p9_qid qid;
1301         int iounit;
1302
1303         p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1304                                                 fid->fid, name, perm, mode);
1305         err = 0;
1306         clnt = fid->clnt;
1307
1308         if (fid->mode != -1)
1309                 return -EINVAL;
1310
1311         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1312                                 mode, extension);
1313         if (IS_ERR(req)) {
1314                 err = PTR_ERR(req);
1315                 goto error;
1316         }
1317
1318         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1319         if (err) {
1320                 trace_9p_protocol_dump(clnt, req->rc);
1321                 goto free_and_error;
1322         }
1323
1324         p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1325                                 qid.type,
1326                                 (unsigned long long)qid.path,
1327                                 qid.version, iounit);
1328
1329         fid->mode = mode;
1330         fid->iounit = iounit;
1331
1332 free_and_error:
1333         p9_free_req(clnt, req);
1334 error:
1335         return err;
1336 }
1337 EXPORT_SYMBOL(p9_client_fcreate);
1338
1339 int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, gid_t gid,
1340                 struct p9_qid *qid)
1341 {
1342         int err = 0;
1343         struct p9_client *clnt;
1344         struct p9_req_t *req;
1345
1346         p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1347                         dfid->fid, name, symtgt);
1348         clnt = dfid->clnt;
1349
1350         req = p9_client_rpc(clnt, P9_TSYMLINK, "dssd", dfid->fid, name, symtgt,
1351                         gid);
1352         if (IS_ERR(req)) {
1353                 err = PTR_ERR(req);
1354                 goto error;
1355         }
1356
1357         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1358         if (err) {
1359                 trace_9p_protocol_dump(clnt, req->rc);
1360                 goto free_and_error;
1361         }
1362
1363         p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1364                         qid->type, (unsigned long long)qid->path, qid->version);
1365
1366 free_and_error:
1367         p9_free_req(clnt, req);
1368 error:
1369         return err;
1370 }
1371 EXPORT_SYMBOL(p9_client_symlink);
1372
1373 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
1374 {
1375         struct p9_client *clnt;
1376         struct p9_req_t *req;
1377
1378         p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1379                         dfid->fid, oldfid->fid, newname);
1380         clnt = dfid->clnt;
1381         req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1382                         newname);
1383         if (IS_ERR(req))
1384                 return PTR_ERR(req);
1385
1386         p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
1387         p9_free_req(clnt, req);
1388         return 0;
1389 }
1390 EXPORT_SYMBOL(p9_client_link);
1391
1392 int p9_client_fsync(struct p9_fid *fid, int datasync)
1393 {
1394         int err;
1395         struct p9_client *clnt;
1396         struct p9_req_t *req;
1397
1398         p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1399                         fid->fid, datasync);
1400         err = 0;
1401         clnt = fid->clnt;
1402
1403         req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1404         if (IS_ERR(req)) {
1405                 err = PTR_ERR(req);
1406                 goto error;
1407         }
1408
1409         p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1410
1411         p9_free_req(clnt, req);
1412
1413 error:
1414         return err;
1415 }
1416 EXPORT_SYMBOL(p9_client_fsync);
1417
1418 int p9_client_clunk(struct p9_fid *fid)
1419 {
1420         int err;
1421         struct p9_client *clnt;
1422         struct p9_req_t *req;
1423
1424         if (!fid) {
1425                 pr_warn("%s (%d): Trying to clunk with NULL fid\n",
1426                         __func__, task_pid_nr(current));
1427                 dump_stack();
1428                 return 0;
1429         }
1430
1431         p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d\n", fid->fid);
1432         err = 0;
1433         clnt = fid->clnt;
1434
1435         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1436         if (IS_ERR(req)) {
1437                 err = PTR_ERR(req);
1438                 goto error;
1439         }
1440
1441         p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1442
1443         p9_free_req(clnt, req);
1444 error:
1445         /*
1446          * Fid is not valid even after a failed clunk
1447          */
1448         p9_fid_destroy(fid);
1449         return err;
1450 }
1451 EXPORT_SYMBOL(p9_client_clunk);
1452
1453 int p9_client_remove(struct p9_fid *fid)
1454 {
1455         int err;
1456         struct p9_client *clnt;
1457         struct p9_req_t *req;
1458
1459         p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1460         err = 0;
1461         clnt = fid->clnt;
1462
1463         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1464         if (IS_ERR(req)) {
1465                 err = PTR_ERR(req);
1466                 goto error;
1467         }
1468
1469         p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1470
1471         p9_free_req(clnt, req);
1472 error:
1473         p9_fid_destroy(fid);
1474         return err;
1475 }
1476 EXPORT_SYMBOL(p9_client_remove);
1477
1478 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1479 {
1480         int err = 0;
1481         struct p9_req_t *req;
1482         struct p9_client *clnt;
1483
1484         p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1485                    dfid->fid, name, flags);
1486
1487         clnt = dfid->clnt;
1488         req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1489         if (IS_ERR(req)) {
1490                 err = PTR_ERR(req);
1491                 goto error;
1492         }
1493         p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1494
1495         p9_free_req(clnt, req);
1496 error:
1497         return err;
1498 }
1499 EXPORT_SYMBOL(p9_client_unlinkat);
1500
1501 int
1502 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1503                                                                 u32 count)
1504 {
1505         char *dataptr;
1506         int kernel_buf = 0;
1507         struct p9_req_t *req;
1508         struct p9_client *clnt;
1509         int err, rsize, non_zc = 0;
1510
1511
1512         p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
1513                    fid->fid, (long long unsigned) offset, count);
1514         err = 0;
1515         clnt = fid->clnt;
1516
1517         rsize = fid->iounit;
1518         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1519                 rsize = clnt->msize - P9_IOHDRSZ;
1520
1521         if (count < rsize)
1522                 rsize = count;
1523
1524         /* Don't bother zerocopy for small IO (< 1024) */
1525         if (clnt->trans_mod->zc_request && rsize > 1024) {
1526                 char *indata;
1527                 if (data) {
1528                         kernel_buf = 1;
1529                         indata = data;
1530                 } else
1531                         indata = (char *)udata;
1532                 /*
1533                  * response header len is 11
1534                  * PDU Header(7) + IO Size (4)
1535                  */
1536                 req = p9_client_zc_rpc(clnt, P9_TREAD, indata, NULL, rsize, 0,
1537                                        11, kernel_buf, "dqd", fid->fid,
1538                                        offset, rsize);
1539         } else {
1540                 non_zc = 1;
1541                 req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1542                                     rsize);
1543         }
1544         if (IS_ERR(req)) {
1545                 err = PTR_ERR(req);
1546                 goto error;
1547         }
1548
1549         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1550         if (err) {
1551                 trace_9p_protocol_dump(clnt, req->rc);
1552                 goto free_and_error;
1553         }
1554
1555         p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1556
1557         if (non_zc) {
1558                 if (data) {
1559                         memmove(data, dataptr, count);
1560                 } else {
1561                         err = copy_to_user(udata, dataptr, count);
1562                         if (err) {
1563                                 err = -EFAULT;
1564                                 goto free_and_error;
1565                         }
1566                 }
1567         }
1568         p9_free_req(clnt, req);
1569         return count;
1570
1571 free_and_error:
1572         p9_free_req(clnt, req);
1573 error:
1574         return err;
1575 }
1576 EXPORT_SYMBOL(p9_client_read);
1577
1578 int
1579 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1580                                                         u64 offset, u32 count)
1581 {
1582         int err, rsize;
1583         int kernel_buf = 0;
1584         struct p9_client *clnt;
1585         struct p9_req_t *req;
1586
1587         p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1588                                 fid->fid, (long long unsigned) offset, count);
1589         err = 0;
1590         clnt = fid->clnt;
1591
1592         rsize = fid->iounit;
1593         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1594                 rsize = clnt->msize - P9_IOHDRSZ;
1595
1596         if (count < rsize)
1597                 rsize = count;
1598
1599         /* Don't bother zerocopy for small IO (< 1024) */
1600         if (clnt->trans_mod->zc_request && rsize > 1024) {
1601                 char *odata;
1602                 if (data) {
1603                         kernel_buf = 1;
1604                         odata = data;
1605                 } else
1606                         odata = (char *)udata;
1607                 req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, odata, 0, rsize,
1608                                        P9_ZC_HDR_SZ, kernel_buf, "dqd",
1609                                        fid->fid, offset, rsize);
1610         } else {
1611                 if (data)
1612                         req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid,
1613                                             offset, rsize, data);
1614                 else
1615                         req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid,
1616                                             offset, rsize, udata);
1617         }
1618         if (IS_ERR(req)) {
1619                 err = PTR_ERR(req);
1620                 goto error;
1621         }
1622
1623         err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1624         if (err) {
1625                 trace_9p_protocol_dump(clnt, req->rc);
1626                 goto free_and_error;
1627         }
1628
1629         p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1630
1631         p9_free_req(clnt, req);
1632         return count;
1633
1634 free_and_error:
1635         p9_free_req(clnt, req);
1636 error:
1637         return err;
1638 }
1639 EXPORT_SYMBOL(p9_client_write);
1640
1641 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1642 {
1643         int err;
1644         struct p9_client *clnt;
1645         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1646         struct p9_req_t *req;
1647         u16 ignored;
1648
1649         p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1650
1651         if (!ret)
1652                 return ERR_PTR(-ENOMEM);
1653
1654         err = 0;
1655         clnt = fid->clnt;
1656
1657         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1658         if (IS_ERR(req)) {
1659                 err = PTR_ERR(req);
1660                 goto error;
1661         }
1662
1663         err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1664         if (err) {
1665                 trace_9p_protocol_dump(clnt, req->rc);
1666                 p9_free_req(clnt, req);
1667                 goto error;
1668         }
1669
1670         p9_debug(P9_DEBUG_9P,
1671                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1672                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1673                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1674                 "<<<    uid=%d gid=%d n_muid=%d\n",
1675                 ret->size, ret->type, ret->dev, ret->qid.type,
1676                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1677                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1678                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1679                 ret->n_uid, ret->n_gid, ret->n_muid);
1680
1681         p9_free_req(clnt, req);
1682         return ret;
1683
1684 error:
1685         kfree(ret);
1686         return ERR_PTR(err);
1687 }
1688 EXPORT_SYMBOL(p9_client_stat);
1689
1690 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1691                                                         u64 request_mask)
1692 {
1693         int err;
1694         struct p9_client *clnt;
1695         struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1696                                                                 GFP_KERNEL);
1697         struct p9_req_t *req;
1698
1699         p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1700                                                         fid->fid, request_mask);
1701
1702         if (!ret)
1703                 return ERR_PTR(-ENOMEM);
1704
1705         err = 0;
1706         clnt = fid->clnt;
1707
1708         req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1709         if (IS_ERR(req)) {
1710                 err = PTR_ERR(req);
1711                 goto error;
1712         }
1713
1714         err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1715         if (err) {
1716                 trace_9p_protocol_dump(clnt, req->rc);
1717                 p9_free_req(clnt, req);
1718                 goto error;
1719         }
1720
1721         p9_debug(P9_DEBUG_9P,
1722                 "<<< RGETATTR st_result_mask=%lld\n"
1723                 "<<< qid=%x.%llx.%x\n"
1724                 "<<< st_mode=%8.8x st_nlink=%llu\n"
1725                 "<<< st_uid=%d st_gid=%d\n"
1726                 "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1727                 "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1728                 "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1729                 "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1730                 "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1731                 "<<< st_gen=%lld st_data_version=%lld",
1732                 ret->st_result_mask, ret->qid.type, ret->qid.path,
1733                 ret->qid.version, ret->st_mode, ret->st_nlink, ret->st_uid,
1734                 ret->st_gid, ret->st_rdev, ret->st_size, ret->st_blksize,
1735                 ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1736                 ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1737                 ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1738                 ret->st_gen, ret->st_data_version);
1739
1740         p9_free_req(clnt, req);
1741         return ret;
1742
1743 error:
1744         kfree(ret);
1745         return ERR_PTR(err);
1746 }
1747 EXPORT_SYMBOL(p9_client_getattr_dotl);
1748
1749 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1750 {
1751         int ret;
1752
1753         /* NOTE: size shouldn't include its own length */
1754         /* size[2] type[2] dev[4] qid[13] */
1755         /* mode[4] atime[4] mtime[4] length[8]*/
1756         /* name[s] uid[s] gid[s] muid[s] */
1757         ret = 2+4+13+4+4+4+8+2+2+2+2;
1758
1759         if (wst->name)
1760                 ret += strlen(wst->name);
1761         if (wst->uid)
1762                 ret += strlen(wst->uid);
1763         if (wst->gid)
1764                 ret += strlen(wst->gid);
1765         if (wst->muid)
1766                 ret += strlen(wst->muid);
1767
1768         if ((proto_version == p9_proto_2000u) ||
1769                 (proto_version == p9_proto_2000L)) {
1770                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1771                 if (wst->extension)
1772                         ret += strlen(wst->extension);
1773         }
1774
1775         return ret;
1776 }
1777
1778 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1779 {
1780         int err;
1781         struct p9_req_t *req;
1782         struct p9_client *clnt;
1783
1784         err = 0;
1785         clnt = fid->clnt;
1786         wst->size = p9_client_statsize(wst, clnt->proto_version);
1787         p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1788         p9_debug(P9_DEBUG_9P,
1789                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1790                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1791                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1792                 "     uid=%d gid=%d n_muid=%d\n",
1793                 wst->size, wst->type, wst->dev, wst->qid.type,
1794                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1795                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1796                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1797                 wst->n_uid, wst->n_gid, wst->n_muid);
1798
1799         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1800         if (IS_ERR(req)) {
1801                 err = PTR_ERR(req);
1802                 goto error;
1803         }
1804
1805         p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1806
1807         p9_free_req(clnt, req);
1808 error:
1809         return err;
1810 }
1811 EXPORT_SYMBOL(p9_client_wstat);
1812
1813 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1814 {
1815         int err;
1816         struct p9_req_t *req;
1817         struct p9_client *clnt;
1818
1819         err = 0;
1820         clnt = fid->clnt;
1821         p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1822         p9_debug(P9_DEBUG_9P,
1823                 "    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1824                 "    atime_sec=%lld atime_nsec=%lld\n"
1825                 "    mtime_sec=%lld mtime_nsec=%lld\n",
1826                 p9attr->valid, p9attr->mode, p9attr->uid, p9attr->gid,
1827                 p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1828                 p9attr->mtime_sec, p9attr->mtime_nsec);
1829
1830         req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1831
1832         if (IS_ERR(req)) {
1833                 err = PTR_ERR(req);
1834                 goto error;
1835         }
1836         p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1837         p9_free_req(clnt, req);
1838 error:
1839         return err;
1840 }
1841 EXPORT_SYMBOL(p9_client_setattr);
1842
1843 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1844 {
1845         int err;
1846         struct p9_req_t *req;
1847         struct p9_client *clnt;
1848
1849         err = 0;
1850         clnt = fid->clnt;
1851
1852         p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1853
1854         req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1855         if (IS_ERR(req)) {
1856                 err = PTR_ERR(req);
1857                 goto error;
1858         }
1859
1860         err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1861                 &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1862                 &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1863         if (err) {
1864                 trace_9p_protocol_dump(clnt, req->rc);
1865                 p9_free_req(clnt, req);
1866                 goto error;
1867         }
1868
1869         p9_debug(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1870                 "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1871                 "fsid %llu namelen %ld\n",
1872                 fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1873                 sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1874                 sb->fsid, (long int)sb->namelen);
1875
1876         p9_free_req(clnt, req);
1877 error:
1878         return err;
1879 }
1880 EXPORT_SYMBOL(p9_client_statfs);
1881
1882 int p9_client_rename(struct p9_fid *fid,
1883                      struct p9_fid *newdirfid, const char *name)
1884 {
1885         int err;
1886         struct p9_req_t *req;
1887         struct p9_client *clnt;
1888
1889         err = 0;
1890         clnt = fid->clnt;
1891
1892         p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1893                         fid->fid, newdirfid->fid, name);
1894
1895         req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1896                         newdirfid->fid, name);
1897         if (IS_ERR(req)) {
1898                 err = PTR_ERR(req);
1899                 goto error;
1900         }
1901
1902         p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1903
1904         p9_free_req(clnt, req);
1905 error:
1906         return err;
1907 }
1908 EXPORT_SYMBOL(p9_client_rename);
1909
1910 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1911                        struct p9_fid *newdirfid, const char *new_name)
1912 {
1913         int err;
1914         struct p9_req_t *req;
1915         struct p9_client *clnt;
1916
1917         err = 0;
1918         clnt = olddirfid->clnt;
1919
1920         p9_debug(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1921                    " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1922                    newdirfid->fid, new_name);
1923
1924         req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1925                             old_name, newdirfid->fid, new_name);
1926         if (IS_ERR(req)) {
1927                 err = PTR_ERR(req);
1928                 goto error;
1929         }
1930
1931         p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
1932                    newdirfid->fid, new_name);
1933
1934         p9_free_req(clnt, req);
1935 error:
1936         return err;
1937 }
1938 EXPORT_SYMBOL(p9_client_renameat);
1939
1940 /*
1941  * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1942  */
1943 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1944                                 const char *attr_name, u64 *attr_size)
1945 {
1946         int err;
1947         struct p9_req_t *req;
1948         struct p9_client *clnt;
1949         struct p9_fid *attr_fid;
1950
1951         err = 0;
1952         clnt = file_fid->clnt;
1953         attr_fid = p9_fid_create(clnt);
1954         if (IS_ERR(attr_fid)) {
1955                 err = PTR_ERR(attr_fid);
1956                 attr_fid = NULL;
1957                 goto error;
1958         }
1959         p9_debug(P9_DEBUG_9P,
1960                 ">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
1961                 file_fid->fid, attr_fid->fid, attr_name);
1962
1963         req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
1964                         file_fid->fid, attr_fid->fid, attr_name);
1965         if (IS_ERR(req)) {
1966                 err = PTR_ERR(req);
1967                 goto error;
1968         }
1969         err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
1970         if (err) {
1971                 trace_9p_protocol_dump(clnt, req->rc);
1972                 p9_free_req(clnt, req);
1973                 goto clunk_fid;
1974         }
1975         p9_free_req(clnt, req);
1976         p9_debug(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
1977                 attr_fid->fid, *attr_size);
1978         return attr_fid;
1979 clunk_fid:
1980         p9_client_clunk(attr_fid);
1981         attr_fid = NULL;
1982 error:
1983         if (attr_fid && (attr_fid != file_fid))
1984                 p9_fid_destroy(attr_fid);
1985
1986         return ERR_PTR(err);
1987 }
1988 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
1989
1990 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
1991                         u64 attr_size, int flags)
1992 {
1993         int err;
1994         struct p9_req_t *req;
1995         struct p9_client *clnt;
1996
1997         p9_debug(P9_DEBUG_9P,
1998                 ">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
1999                 fid->fid, name, (long long)attr_size, flags);
2000         err = 0;
2001         clnt = fid->clnt;
2002         req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2003                         fid->fid, name, attr_size, flags);
2004         if (IS_ERR(req)) {
2005                 err = PTR_ERR(req);
2006                 goto error;
2007         }
2008         p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2009         p9_free_req(clnt, req);
2010 error:
2011         return err;
2012 }
2013 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2014
2015 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2016 {
2017         int err, rsize, non_zc = 0;
2018         struct p9_client *clnt;
2019         struct p9_req_t *req;
2020         char *dataptr;
2021
2022         p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2023                                 fid->fid, (long long unsigned) offset, count);
2024
2025         err = 0;
2026         clnt = fid->clnt;
2027
2028         rsize = fid->iounit;
2029         if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2030                 rsize = clnt->msize - P9_READDIRHDRSZ;
2031
2032         if (count < rsize)
2033                 rsize = count;
2034
2035         /* Don't bother zerocopy for small IO (< 1024) */
2036         if (clnt->trans_mod->zc_request && rsize > 1024) {
2037                 /*
2038                  * response header len is 11
2039                  * PDU Header(7) + IO Size (4)
2040                  */
2041                 req = p9_client_zc_rpc(clnt, P9_TREADDIR, data, NULL, rsize, 0,
2042                                        11, 1, "dqd", fid->fid, offset, rsize);
2043         } else {
2044                 non_zc = 1;
2045                 req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2046                                     offset, rsize);
2047         }
2048         if (IS_ERR(req)) {
2049                 err = PTR_ERR(req);
2050                 goto error;
2051         }
2052
2053         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2054         if (err) {
2055                 trace_9p_protocol_dump(clnt, req->rc);
2056                 goto free_and_error;
2057         }
2058
2059         p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2060
2061         if (non_zc)
2062                 memmove(data, dataptr, count);
2063
2064         p9_free_req(clnt, req);
2065         return count;
2066
2067 free_and_error:
2068         p9_free_req(clnt, req);
2069 error:
2070         return err;
2071 }
2072 EXPORT_SYMBOL(p9_client_readdir);
2073
2074 int p9_client_mknod_dotl(struct p9_fid *fid, char *name, int mode,
2075                         dev_t rdev, gid_t gid, struct p9_qid *qid)
2076 {
2077         int err;
2078         struct p9_client *clnt;
2079         struct p9_req_t *req;
2080
2081         err = 0;
2082         clnt = fid->clnt;
2083         p9_debug(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2084                 "minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2085         req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddd", fid->fid, name, mode,
2086                 MAJOR(rdev), MINOR(rdev), gid);
2087         if (IS_ERR(req))
2088                 return PTR_ERR(req);
2089
2090         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2091         if (err) {
2092                 trace_9p_protocol_dump(clnt, req->rc);
2093                 goto error;
2094         }
2095         p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2096                                 (unsigned long long)qid->path, qid->version);
2097
2098 error:
2099         p9_free_req(clnt, req);
2100         return err;
2101
2102 }
2103 EXPORT_SYMBOL(p9_client_mknod_dotl);
2104
2105 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
2106                                 gid_t gid, struct p9_qid *qid)
2107 {
2108         int err;
2109         struct p9_client *clnt;
2110         struct p9_req_t *req;
2111
2112         err = 0;
2113         clnt = fid->clnt;
2114         p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2115                  fid->fid, name, mode, gid);
2116         req = p9_client_rpc(clnt, P9_TMKDIR, "dsdd", fid->fid, name, mode,
2117                 gid);
2118         if (IS_ERR(req))
2119                 return PTR_ERR(req);
2120
2121         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2122         if (err) {
2123                 trace_9p_protocol_dump(clnt, req->rc);
2124                 goto error;
2125         }
2126         p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2127                                 (unsigned long long)qid->path, qid->version);
2128
2129 error:
2130         p9_free_req(clnt, req);
2131         return err;
2132
2133 }
2134 EXPORT_SYMBOL(p9_client_mkdir_dotl);
2135
2136 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2137 {
2138         int err;
2139         struct p9_client *clnt;
2140         struct p9_req_t *req;
2141
2142         err = 0;
2143         clnt = fid->clnt;
2144         p9_debug(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2145                         "start %lld length %lld proc_id %d client_id %s\n",
2146                         fid->fid, flock->type, flock->flags, flock->start,
2147                         flock->length, flock->proc_id, flock->client_id);
2148
2149         req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2150                                 flock->flags, flock->start, flock->length,
2151                                         flock->proc_id, flock->client_id);
2152
2153         if (IS_ERR(req))
2154                 return PTR_ERR(req);
2155
2156         err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2157         if (err) {
2158                 trace_9p_protocol_dump(clnt, req->rc);
2159                 goto error;
2160         }
2161         p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2162 error:
2163         p9_free_req(clnt, req);
2164         return err;
2165
2166 }
2167 EXPORT_SYMBOL(p9_client_lock_dotl);
2168
2169 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2170 {
2171         int err;
2172         struct p9_client *clnt;
2173         struct p9_req_t *req;
2174
2175         err = 0;
2176         clnt = fid->clnt;
2177         p9_debug(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
2178                 "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2179                 glock->start, glock->length, glock->proc_id, glock->client_id);
2180
2181         req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
2182                 glock->start, glock->length, glock->proc_id, glock->client_id);
2183
2184         if (IS_ERR(req))
2185                 return PTR_ERR(req);
2186
2187         err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2188                         &glock->start, &glock->length, &glock->proc_id,
2189                         &glock->client_id);
2190         if (err) {
2191                 trace_9p_protocol_dump(clnt, req->rc);
2192                 goto error;
2193         }
2194         p9_debug(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2195                 "proc_id %d client_id %s\n", glock->type, glock->start,
2196                 glock->length, glock->proc_id, glock->client_id);
2197 error:
2198         p9_free_req(clnt, req);
2199         return err;
2200 }
2201 EXPORT_SYMBOL(p9_client_getlock_dotl);
2202
2203 int p9_client_readlink(struct p9_fid *fid, char **target)
2204 {
2205         int err;
2206         struct p9_client *clnt;
2207         struct p9_req_t *req;
2208
2209         err = 0;
2210         clnt = fid->clnt;
2211         p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2212
2213         req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2214         if (IS_ERR(req))
2215                 return PTR_ERR(req);
2216
2217         err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2218         if (err) {
2219                 trace_9p_protocol_dump(clnt, req->rc);
2220                 goto error;
2221         }
2222         p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2223 error:
2224         p9_free_req(clnt, req);
2225         return err;
2226 }
2227 EXPORT_SYMBOL(p9_client_readlink);