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 #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 /*
  80  * Some error codes are taken directly from the server replies,
  81  * make sure they are valid.
  82  */
  83 static int safe_errno(int err)
  84 {
  85         if ((err > 0) || (err < -MAX_ERRNO)) {
  86                 p9_debug(P9_DEBUG_ERROR, "Invalid error code %d\n", err);
  87                 return -EPROTO;
  88         }
  89         return err;
  90 }
  91
  92
  93 /* Interpret mount option for protocol version */
  94 static int get_protocol_version(char *s)
  95 {
  96         int version = -EINVAL;
  97
  98         if (!strcmp(s, "9p2000")) {
  99                 version = p9_proto_legacy;
 100                 p9_debug(P9_DEBUG_9P, "Protocol version: Legacy\n");
 101         } else if (!strcmp(s, "9p2000.u")) {
 102                 version = p9_proto_2000u;
 103                 p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
 104         } else if (!strcmp(s, "9p2000.L")) {
 105                 version = p9_proto_2000L;
 106                 p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.L\n");
 107         } else
 108                 pr_info("Unknown protocol version %s\n", s);
 109
 110         return version;
 111 }
 112
 113 /**
 114  * parse_options - parse mount options into client structure
 115  * @opts: options string passed from mount
 116  * @clnt: existing v9fs client information
 117  *
 118  * Return 0 upon success, -ERRNO upon failure
 119  */
 120
 121 static int parse_opts(char *opts, struct p9_client *clnt)
 122 {
 123         char *options, *tmp_options;
 124         char *p;
 125         substring_t args[MAX_OPT_ARGS];
 126         int option;
 127         char *s;
 128         int ret = 0;
 129
 130         clnt->proto_version = p9_proto_2000u;
 131         clnt->msize = 8192;
 132
 133         if (!opts)
 134                 return 0;
 135
 136         tmp_options = kstrdup(opts, GFP_KERNEL);
 137         if (!tmp_options) {
 138                 p9_debug(P9_DEBUG_ERROR,
 139                          "failed to allocate copy of option string\n");
 140                 return -ENOMEM;
 141         }
 142         options = tmp_options;
 143
 144         while ((p = strsep(&options, ",")) != NULL) {
 145                 int token, r;
 146                 if (!*p)
 147                         continue;
 148                 token = match_token(p, tokens, args);
 149                 switch (token) {
 150                 case Opt_msize:
 151                         r = match_int(&args[0], &option);
 152                         if (r < 0) {
 153                                 p9_debug(P9_DEBUG_ERROR,
 154                                          "integer field, but no integer?\n");
 155                                 ret = r;
 156                                 continue;
 157                         }
 158                         clnt->msize = option;
 159                         break;
 160                 case Opt_trans:
 161                         s = match_strdup(&args[0]);
 162                         if (!s) {
 163                                 ret = -ENOMEM;
 164                                 p9_debug(P9_DEBUG_ERROR,
 165                                          "problem allocating copy of trans arg\n");
 166                                 goto free_and_return;
 167                          }
 168                         clnt->trans_mod = v9fs_get_trans_by_name(s);
 169                         if (clnt->trans_mod == NULL) {
 170                                 pr_info("Could not find request transport: %s\n",
 171                                         s);
 172                                 ret = -EINVAL;
 173                                 kfree(s);
 174                                 goto free_and_return;
 175                         }
 176                         kfree(s);
 177                         break;
 178                 case Opt_legacy:
 179                         clnt->proto_version = p9_proto_legacy;
 180                         break;
 181                 case Opt_version:
 182                         s = match_strdup(&args[0]);
 183                         if (!s) {
 184                                 ret = -ENOMEM;
 185                                 p9_debug(P9_DEBUG_ERROR,
 186                                          "problem allocating copy of version arg\n");
 187                                 goto free_and_return;
 188                         }
 189                         ret = get_protocol_version(s);
 190                         if (ret == -EINVAL) {
 191                                 kfree(s);
 192                                 goto free_and_return;
 193                         }
 194                         kfree(s);
 195                         clnt->proto_version = ret;
 196                         break;
 197                 default:
 198                         continue;
 199                 }
 200         }
 201
 202 free_and_return:
 203         kfree(tmp_options);
 204         return ret;
 205 }
 206
 207 /**
 208  * p9_tag_alloc - lookup/allocate a request by tag
 209  * @c: client session to lookup tag within
 210  * @tag: numeric id for transaction
 211  *
 212  * this is a simple array lookup, but will grow the
 213  * request_slots as necessary to accommodate transaction
 214  * ids which did not previously have a slot.
 215  *
 216  * this code relies on the client spinlock to manage locks, its
 217  * possible we should switch to something else, but I'd rather
 218  * stick with something low-overhead for the common case.
 219  *
 220  */
 221
 222 static struct p9_req_t *
 223 p9_tag_alloc(struct p9_client *c, u16 tag, unsigned int max_size)
 224 {
 225         unsigned long flags;
 226         int row, col;
 227         struct p9_req_t *req;
 228         int alloc_msize = min(c->msize, max_size);
 229
 230         /* This looks up the original request by tag so we know which
 231          * buffer to read the data into */
 232         tag++;
 233
 234         if (tag >= c->max_tag) {
 235                 spin_lock_irqsave(&c->lock, flags);
 236                 /* check again since original check was outside of lock */
 237                 while (tag >= c->max_tag) {
 238                         row = (tag / P9_ROW_MAXTAG);
 239                         c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
 240                                         sizeof(struct p9_req_t), GFP_ATOMIC);
 241
 242                         if (!c->reqs[row]) {
 243                                 pr_err("Couldn't grow tag array\n");
 244                                 spin_unlock_irqrestore(&c->lock, flags);
 245                                 return ERR_PTR(-ENOMEM);
 246                         }
 247                         for (col = 0; col < P9_ROW_MAXTAG; col++) {
 248                                 c->reqs[row][col].status = REQ_STATUS_IDLE;
 249                                 c->reqs[row][col].tc = NULL;
 250                         }
 251                         c->max_tag += P9_ROW_MAXTAG;
 252                 }
 253                 spin_unlock_irqrestore(&c->lock, flags);
 254         }
 255         row = tag / P9_ROW_MAXTAG;
 256         col = tag % P9_ROW_MAXTAG;
 257
 258         req = &c->reqs[row][col];
 259         if (!req->tc) {
 260                 req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_NOFS);
 261                 if (!req->wq) {
 262                         pr_err("Couldn't grow tag array\n");
 263                         return ERR_PTR(-ENOMEM);
 264                 }
 265                 init_waitqueue_head(req->wq);
 266                 req->tc = kmalloc(sizeof(struct p9_fcall) + alloc_msize,
 267                                   GFP_NOFS);
 268                 req->rc = kmalloc(sizeof(struct p9_fcall) + alloc_msize,
 269                                   GFP_NOFS);
 270                 if ((!req->tc) || (!req->rc)) {
 271                         pr_err("Couldn't grow tag array\n");
 272                         kfree(req->tc);
 273                         kfree(req->rc);
 274                         kfree(req->wq);
 275                         req->tc = req->rc = NULL;
 276                         req->wq = NULL;
 277                         return ERR_PTR(-ENOMEM);
 278                 }
 279                 req->tc->capacity = alloc_msize;
 280                 req->rc->capacity = alloc_msize;
 281                 req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
 282                 req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall);
 283         }
 284
 285         p9pdu_reset(req->tc);
 286         p9pdu_reset(req->rc);
 287
 288         req->tc->tag = tag-1;
 289         req->status = REQ_STATUS_ALLOC;
 290
 291         return &c->reqs[row][col];
 292 }
 293
 294 /**
 295  * p9_tag_lookup - lookup a request by tag
 296  * @c: client session to lookup tag within
 297  * @tag: numeric id for transaction
 298  *
 299  */
 300
 301 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
 302 {
 303         int row, col;
 304
 305         /* This looks up the original request by tag so we know which
 306          * buffer to read the data into */
 307         tag++;
 308
 309         if(tag >= c->max_tag)
 310                 return NULL;
 311
 312         row = tag / P9_ROW_MAXTAG;
 313         col = tag % P9_ROW_MAXTAG;
 314
 315         return &c->reqs[row][col];
 316 }
 317 EXPORT_SYMBOL(p9_tag_lookup);
 318
 319 /**
 320  * p9_tag_init - setup tags structure and contents
 321  * @c:  v9fs client struct
 322  *
 323  * This initializes the tags structure for each client instance.
 324  *
 325  */
 326
 327 static int p9_tag_init(struct p9_client *c)
 328 {
 329         int err = 0;
 330
 331         c->tagpool = p9_idpool_create();
 332         if (IS_ERR(c->tagpool)) {
 333                 err = PTR_ERR(c->tagpool);
 334                 goto error;
 335         }
 336         err = p9_idpool_get(c->tagpool); /* reserve tag 0 */
 337         if (err < 0) {
 338                 p9_idpool_destroy(c->tagpool);
 339                 goto error;
 340         }
 341         c->max_tag = 0;
 342 error:
 343         return err;
 344 }
 345
 346 /**
 347  * p9_tag_cleanup - cleans up tags structure and reclaims resources
 348  * @c:  v9fs client struct
 349  *
 350  * This frees resources associated with the tags structure
 351  *
 352  */
 353 static void p9_tag_cleanup(struct p9_client *c)
 354 {
 355         int row, col;
 356
 357         /* check to insure all requests are idle */
 358         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 359                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 360                         if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
 361                                 p9_debug(P9_DEBUG_MUX,
 362                                          "Attempting to cleanup non-free tag %d,%d\n",
 363                                          row, col);
 364                                 /* TODO: delay execution of cleanup */
 365                                 return;
 366                         }
 367                 }
 368         }
 369
 370         if (c->tagpool) {
 371                 p9_idpool_put(0, c->tagpool); /* free reserved tag 0 */
 372                 p9_idpool_destroy(c->tagpool);
 373         }
 374
 375         /* free requests associated with tags */
 376         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 377                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 378                         kfree(c->reqs[row][col].wq);
 379                         kfree(c->reqs[row][col].tc);
 380                         kfree(c->reqs[row][col].rc);
 381                 }
 382                 kfree(c->reqs[row]);
 383         }
 384         c->max_tag = 0;
 385 }
 386
 387 /**
 388  * p9_free_req - free a request and clean-up as necessary
 389  * c: client state
 390  * r: request to release
 391  *
 392  */
 393
 394 static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
 395 {
 396         int tag = r->tc->tag;
 397         p9_debug(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
 398
 399         r->status = REQ_STATUS_IDLE;
 400         if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
 401                 p9_idpool_put(tag, c->tagpool);
 402 }
 403
 404 /**
 405  * p9_client_cb - call back from transport to client
 406  * c: client state
 407  * req: request received
 408  *
 409  */
 410 void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
 411 {
 412         p9_debug(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
 413         wake_up(req->wq);
 414         p9_debug(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
 415 }
 416 EXPORT_SYMBOL(p9_client_cb);
 417
 418 /**
 419  * p9_parse_header - parse header arguments out of a packet
 420  * @pdu: packet to parse
 421  * @size: size of packet
 422  * @type: type of request
 423  * @tag: tag of packet
 424  * @rewind: set if we need to rewind offset afterwards
 425  */
 426
 427 int
 428 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
 429                                                                 int rewind)
 430 {
 431         int8_t r_type;
 432         int16_t r_tag;
 433         int32_t r_size;
 434         int offset = pdu->offset;
 435         int err;
 436
 437         pdu->offset = 0;
 438         if (pdu->size == 0)
 439                 pdu->size = 7;
 440
 441         err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
 442         if (err)
 443                 goto rewind_and_exit;
 444
 445         pdu->size = r_size;
 446         pdu->id = r_type;
 447         pdu->tag = r_tag;
 448
 449         p9_debug(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n",
 450                  pdu->size, pdu->id, pdu->tag);
 451
 452         if (type)
 453                 *type = r_type;
 454         if (tag)
 455                 *tag = r_tag;
 456         if (size)
 457                 *size = r_size;
 458
 459
 460 rewind_and_exit:
 461         if (rewind)
 462                 pdu->offset = offset;
 463         return err;
 464 }
 465 EXPORT_SYMBOL(p9_parse_header);
 466
 467 /**
 468  * p9_check_errors - check 9p packet for error return and process it
 469  * @c: current client instance
 470  * @req: request to parse and check for error conditions
 471  *
 472  * returns error code if one is discovered, otherwise returns 0
 473  *
 474  * this will have to be more complicated if we have multiple
 475  * error packet types
 476  */
 477
 478 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 479 {
 480         int8_t type;
 481         int err;
 482         int ecode;
 483
 484         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 485         /*
 486          * dump the response from server
 487          * This should be after check errors which poplulate pdu_fcall.
 488          */
 489         trace_9p_protocol_dump(c, req->rc);
 490         if (err) {
 491                 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 492                 return err;
 493         }
 494         if (type != P9_RERROR && type != P9_RLERROR)
 495                 return 0;
 496
 497         if (!p9_is_proto_dotl(c)) {
 498                 char *ename;
 499                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 500                                   &ename, &ecode);
 501                 if (err)
 502                         goto out_err;
 503
 504                 if (p9_is_proto_dotu(c))
 505                         err = -ecode;
 506
 507                 if (!err || !IS_ERR_VALUE(err)) {
 508                         err = p9_errstr2errno(ename, strlen(ename));
 509
 510                         p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 511                                  -ecode, ename);
 512                 }
 513                 kfree(ename);
 514         } else {
 515                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 516                 err = -ecode;
 517
 518                 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 519         }
 520
 521         return err;
 522
 523 out_err:
 524         p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 525
 526         return err;
 527 }
 528
 529 /**
 530  * p9_check_zc_errors - check 9p packet for error return and process it
 531  * @c: current client instance
 532  * @req: request to parse and check for error conditions
 533  * @in_hdrlen: Size of response protocol buffer.
 534  *
 535  * returns error code if one is discovered, otherwise returns 0
 536  *
 537  * this will have to be more complicated if we have multiple
 538  * error packet types
 539  */
 540
 541 static int p9_check_zc_errors(struct p9_client *c, struct p9_req_t *req,
 542                               char *uidata, int in_hdrlen, int kern_buf)
 543 {
 544         int err;
 545         int ecode;
 546         int8_t type;
 547         char *ename = NULL;
 548
 549         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 550         /*
 551          * dump the response from server
 552          * This should be after parse_header which poplulate pdu_fcall.
 553          */
 554         trace_9p_protocol_dump(c, req->rc);
 555         if (err) {
 556                 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 557                 return err;
 558         }
 559
 560         if (type != P9_RERROR && type != P9_RLERROR)
 561                 return 0;
 562
 563         if (!p9_is_proto_dotl(c)) {
 564                 /* Error is reported in string format */
 565                 uint16_t len;
 566                 /* 7 = header size for RERROR, 2 is the size of string len; */
 567                 int inline_len = in_hdrlen - (7 + 2);
 568
 569                 /* Read the size of error string */
 570                 err = p9pdu_readf(req->rc, c->proto_version, "w", &len);
 571                 if (err)
 572                         goto out_err;
 573
 574                 ename = kmalloc(len + 1, GFP_NOFS);
 575                 if (!ename) {
 576                         err = -ENOMEM;
 577                         goto out_err;
 578                 }
 579                 if (len <= inline_len) {
 580                         /* We have error in protocol buffer itself */
 581                         if (pdu_read(req->rc, ename, len)) {
 582                                 err = -EFAULT;
 583                                 goto out_free;
 584
 585                         }
 586                 } else {
 587                         /*
 588                          *  Part of the data is in user space buffer.
 589                          */
 590                         if (pdu_read(req->rc, ename, inline_len)) {
 591                                 err = -EFAULT;
 592                                 goto out_free;
 593
 594                         }
 595                         if (kern_buf) {
 596                                 memcpy(ename + inline_len, uidata,
 597                                        len - inline_len);
 598                         } else {
 599                                 err = copy_from_user(ename + inline_len,
 600                                                      uidata, len - inline_len);
 601                                 if (err) {
 602                                         err = -EFAULT;
 603                                         goto out_free;
 604                                 }
 605                         }
 606                 }
 607                 ename[len] = 0;
 608                 if (p9_is_proto_dotu(c)) {
 609                         /* For dotu we also have error code */
 610                         err = p9pdu_readf(req->rc,
 611                                           c->proto_version, "d", &ecode);
 612                         if (err)
 613                                 goto out_free;
 614                         err = -ecode;
 615                 }
 616                 if (!err || !IS_ERR_VALUE(err)) {
 617                         err = p9_errstr2errno(ename, strlen(ename));
 618
 619                         p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 620                                  -ecode, ename);
 621                 }
 622                 kfree(ename);
 623         } else {
 624                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 625                 err = -ecode;
 626
 627                 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 628         }
 629         return err;
 630
 631 out_free:
 632         kfree(ename);
 633 out_err:
 634         p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 635         return err;
 636 }
 637
 638 static struct p9_req_t *
 639 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
 640
 641 /**
 642  * p9_client_flush - flush (cancel) a request
 643  * @c: client state
 644  * @oldreq: request to cancel
 645  *
 646  * This sents a flush for a particular request and links
 647  * the flush request to the original request.  The current
 648  * code only supports a single flush request although the protocol
 649  * allows for multiple flush requests to be sent for a single request.
 650  *
 651  */
 652
 653 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 654 {
 655         struct p9_req_t *req;
 656         int16_t oldtag;
 657         int err;
 658
 659         err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
 660         if (err)
 661                 return err;
 662
 663         p9_debug(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
 664
 665         req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
 666         if (IS_ERR(req))
 667                 return PTR_ERR(req);
 668
 669
 670         /* if we haven't received a response for oldreq,
 671            remove it from the list. */
 672         spin_lock(&c->lock);
 673         if (oldreq->status == REQ_STATUS_FLSH)
 674                 list_del(&oldreq->req_list);
 675         spin_unlock(&c->lock);
 676
 677         p9_free_req(c, req);
 678         return 0;
 679 }
 680
 681 static struct p9_req_t *p9_client_prepare_req(struct p9_client *c,
 682                                               int8_t type, int req_size,
 683                                               const char *fmt, va_list ap)
 684 {
 685         int tag, err;
 686         struct p9_req_t *req;
 687
 688         p9_debug(P9_DEBUG_MUX, "client %p op %d\n", c, type);
 689
 690         /* we allow for any status other than disconnected */
 691         if (c->status == Disconnected)
 692                 return ERR_PTR(-EIO);
 693
 694         /* if status is begin_disconnected we allow only clunk request */
 695         if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
 696                 return ERR_PTR(-EIO);
 697
 698         tag = P9_NOTAG;
 699         if (type != P9_TVERSION) {
 700                 tag = p9_idpool_get(c->tagpool);
 701                 if (tag < 0)
 702                         return ERR_PTR(-ENOMEM);
 703         }
 704
 705         req = p9_tag_alloc(c, tag, req_size);
 706         if (IS_ERR(req))
 707                 return req;
 708
 709         /* marshall the data */
 710         p9pdu_prepare(req->tc, tag, type);
 711         err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
 712         if (err)
 713                 goto reterr;
 714         p9pdu_finalize(c, req->tc);
 715         trace_9p_client_req(c, type, tag);
 716         return req;
 717 reterr:
 718         p9_free_req(c, req);
 719         return ERR_PTR(err);
 720 }
 721
 722 /**
 723  * p9_client_rpc - issue a request and wait for a response
 724  * @c: client session
 725  * @type: type of request
 726  * @fmt: protocol format string (see protocol.c)
 727  *
 728  * Returns request structure (which client must free using p9_free_req)
 729  */
 730
 731 static struct p9_req_t *
 732 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 733 {
 734         va_list ap;
 735         int sigpending, err;
 736         unsigned long flags;
 737         struct p9_req_t *req;
 738
 739         va_start(ap, fmt);
 740         req = p9_client_prepare_req(c, type, c->msize, fmt, ap);
 741         va_end(ap);
 742         if (IS_ERR(req))
 743                 return req;
 744
 745         if (signal_pending(current)) {
 746                 sigpending = 1;
 747                 clear_thread_flag(TIF_SIGPENDING);
 748         } else
 749                 sigpending = 0;
 750
 751         err = c->trans_mod->request(c, req);
 752         if (err < 0) {
 753                 if (err != -ERESTARTSYS && err != -EFAULT)
 754                         c->status = Disconnected;
 755                 goto reterr;
 756         }
 757 again:
 758         /* Wait for the response */
 759         err = wait_event_interruptible(*req->wq,
 760                                        req->status >= REQ_STATUS_RCVD);
 761
 762         if ((err == -ERESTARTSYS) && (c->status == Connected)
 763                                   && (type == P9_TFLUSH)) {
 764                 sigpending = 1;
 765                 clear_thread_flag(TIF_SIGPENDING);
 766                 goto again;
 767         }
 768
 769         if (req->status == REQ_STATUS_ERROR) {
 770                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 771                 err = req->t_err;
 772         }
 773         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 774                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 775                 sigpending = 1;
 776                 clear_thread_flag(TIF_SIGPENDING);
 777
 778                 if (c->trans_mod->cancel(c, req))
 779                         p9_client_flush(c, req);
 780
 781                 /* if we received the response anyway, don't signal error */
 782                 if (req->status == REQ_STATUS_RCVD)
 783                         err = 0;
 784         }
 785         if (sigpending) {
 786                 spin_lock_irqsave(&current->sighand->siglock, flags);
 787                 recalc_sigpending();
 788                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 789         }
 790         if (err < 0)
 791                 goto reterr;
 792
 793         err = p9_check_errors(c, req);
 794         trace_9p_client_res(c, type, req->rc->tag, err);
 795         if (!err)
 796                 return req;
 797 reterr:
 798         p9_free_req(c, req);
 799         return ERR_PTR(safe_errno(err));
 800 }
 801
 802 /**
 803  * p9_client_zc_rpc - issue a request and wait for a response
 804  * @c: client session
 805  * @type: type of request
 806  * @uidata: user bffer that should be ued for zero copy read
 807  * @uodata: user buffer that shoud be user for zero copy write
 808  * @inlen: read buffer size
 809  * @olen: write buffer size
 810  * @hdrlen: reader header size, This is the size of response protocol data
 811  * @fmt: protocol format string (see protocol.c)
 812  *
 813  * Returns request structure (which client must free using p9_free_req)
 814  */
 815 static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
 816                                          char *uidata, char *uodata,
 817                                          int inlen, int olen, int in_hdrlen,
 818                                          int kern_buf, const char *fmt, ...)
 819 {
 820         va_list ap;
 821         int sigpending, err;
 822         unsigned long flags;
 823         struct p9_req_t *req;
 824
 825         va_start(ap, fmt);
 826         /*
 827          * We allocate a inline protocol data of only 4k bytes.
 828          * The actual content is passed in zero-copy fashion.
 829          */
 830         req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, fmt, ap);
 831         va_end(ap);
 832         if (IS_ERR(req))
 833                 return req;
 834
 835         if (signal_pending(current)) {
 836                 sigpending = 1;
 837                 clear_thread_flag(TIF_SIGPENDING);
 838         } else
 839                 sigpending = 0;
 840
 841         /* If we are called with KERNEL_DS force kern_buf */
 842         if (segment_eq(get_fs(), KERNEL_DS))
 843                 kern_buf = 1;
 844
 845         err = c->trans_mod->zc_request(c, req, uidata, uodata,
 846                                        inlen, olen, in_hdrlen, kern_buf);
 847         if (err < 0) {
 848                 if (err == -EIO)
 849                         c->status = Disconnected;
 850                 goto reterr;
 851         }
 852         if (req->status == REQ_STATUS_ERROR) {
 853                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 854                 err = req->t_err;
 855         }
 856         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 857                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 858                 sigpending = 1;
 859                 clear_thread_flag(TIF_SIGPENDING);
 860
 861                 if (c->trans_mod->cancel(c, req))
 862                         p9_client_flush(c, req);
 863
 864                 /* if we received the response anyway, don't signal error */
 865                 if (req->status == REQ_STATUS_RCVD)
 866                         err = 0;
 867         }
 868         if (sigpending) {
 869                 spin_lock_irqsave(&current->sighand->siglock, flags);
 870                 recalc_sigpending();
 871                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 872         }
 873         if (err < 0)
 874                 goto reterr;
 875
 876         err = p9_check_zc_errors(c, req, uidata, in_hdrlen, kern_buf);
 877         trace_9p_client_res(c, type, req->rc->tag, err);
 878         if (!err)
 879                 return req;
 880 reterr:
 881         p9_free_req(c, req);
 882         return ERR_PTR(safe_errno(err));
 883 }
 884
 885 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 886 {
 887         int ret;
 888         struct p9_fid *fid;
 889         unsigned long flags;
 890
 891         p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt);
 892         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
 893         if (!fid)
 894                 return ERR_PTR(-ENOMEM);
 895
 896         ret = p9_idpool_get(clnt->fidpool);
 897         if (ret < 0) {
 898                 ret = -ENOSPC;
 899                 goto error;
 900         }
 901         fid->fid = ret;
 902
 903         memset(&fid->qid, 0, sizeof(struct p9_qid));
 904         fid->mode = -1;
 905         fid->uid = current_fsuid();
 906         fid->clnt = clnt;
 907         fid->rdir = NULL;
 908         spin_lock_irqsave(&clnt->lock, flags);
 909         list_add(&fid->flist, &clnt->fidlist);
 910         spin_unlock_irqrestore(&clnt->lock, flags);
 911
 912         return fid;
 913
 914 error:
 915         kfree(fid);
 916         return ERR_PTR(ret);
 917 }
 918
 919 static void p9_fid_destroy(struct p9_fid *fid)
 920 {
 921         struct p9_client *clnt;
 922         unsigned long flags;
 923
 924         p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
 925         clnt = fid->clnt;
 926         p9_idpool_put(fid->fid, clnt->fidpool);
 927         spin_lock_irqsave(&clnt->lock, flags);
 928         list_del(&fid->flist);
 929         spin_unlock_irqrestore(&clnt->lock, flags);
 930         kfree(fid->rdir);
 931         kfree(fid);
 932 }
 933
 934 static int p9_client_version(struct p9_client *c)
 935 {
 936         int err = 0;
 937         struct p9_req_t *req;
 938         char *version;
 939         int msize;
 940
 941         p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
 942                  c->msize, c->proto_version);
 943
 944         switch (c->proto_version) {
 945         case p9_proto_2000L:
 946                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 947                                         c->msize, "9P2000.L");
 948                 break;
 949         case p9_proto_2000u:
 950                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 951                                         c->msize, "9P2000.u");
 952                 break;
 953         case p9_proto_legacy:
 954                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 955                                         c->msize, "9P2000");
 956                 break;
 957         default:
 958                 return -EINVAL;
 959                 break;
 960         }
 961
 962         if (IS_ERR(req))
 963                 return PTR_ERR(req);
 964
 965         err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
 966         if (err) {
 967                 p9_debug(P9_DEBUG_9P, "version error %d\n", err);
 968                 trace_9p_protocol_dump(c, req->rc);
 969                 goto error;
 970         }
 971
 972         p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
 973         if (!strncmp(version, "9P2000.L", 8))
 974                 c->proto_version = p9_proto_2000L;
 975         else if (!strncmp(version, "9P2000.u", 8))
 976                 c->proto_version = p9_proto_2000u;
 977         else if (!strncmp(version, "9P2000", 6))
 978                 c->proto_version = p9_proto_legacy;
 979         else {
 980                 err = -EREMOTEIO;
 981                 goto error;
 982         }
 983
 984         if (msize < c->msize)
 985                 c->msize = msize;
 986
 987 error:
 988         kfree(version);
 989         p9_free_req(c, req);
 990
 991         return err;
 992 }
 993
 994 struct p9_client *p9_client_create(const char *dev_name, char *options)
 995 {
 996         int err;
 997         struct p9_client *clnt;
 998
 999         err = 0;
1000         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
1001         if (!clnt)
1002                 return ERR_PTR(-ENOMEM);
1003
1004         clnt->trans_mod = NULL;
1005         clnt->trans = NULL;
1006         spin_lock_init(&clnt->lock);
1007         INIT_LIST_HEAD(&clnt->fidlist);
1008
1009         err = p9_tag_init(clnt);
1010         if (err < 0)
1011                 goto free_client;
1012
1013         err = parse_opts(options, clnt);
1014         if (err < 0)
1015                 goto destroy_tagpool;
1016
1017         if (!clnt->trans_mod)
1018                 clnt->trans_mod = v9fs_get_default_trans();
1019
1020         if (clnt->trans_mod == NULL) {
1021                 err = -EPROTONOSUPPORT;
1022                 p9_debug(P9_DEBUG_ERROR,
1023                          "No transport defined or default transport\n");
1024                 goto destroy_tagpool;
1025         }
1026
1027         clnt->fidpool = p9_idpool_create();
1028         if (IS_ERR(clnt->fidpool)) {
1029                 err = PTR_ERR(clnt->fidpool);
1030                 goto put_trans;
1031         }
1032
1033         p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1034                  clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1035
1036         err = clnt->trans_mod->create(clnt, dev_name, options);
1037         if (err)
1038                 goto destroy_fidpool;
1039
1040         if (clnt->msize > clnt->trans_mod->maxsize)
1041                 clnt->msize = clnt->trans_mod->maxsize;
1042
1043         err = p9_client_version(clnt);
1044         if (err)
1045                 goto close_trans;
1046
1047         return clnt;
1048
1049 close_trans:
1050         clnt->trans_mod->close(clnt);
1051 destroy_fidpool:
1052         p9_idpool_destroy(clnt->fidpool);
1053 put_trans:
1054         v9fs_put_trans(clnt->trans_mod);
1055 destroy_tagpool:
1056         p9_idpool_destroy(clnt->tagpool);
1057 free_client:
1058         kfree(clnt);
1059         return ERR_PTR(err);
1060 }
1061 EXPORT_SYMBOL(p9_client_create);
1062
1063 void p9_client_destroy(struct p9_client *clnt)
1064 {
1065         struct p9_fid *fid, *fidptr;
1066
1067         p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
1068
1069         if (clnt->trans_mod)
1070                 clnt->trans_mod->close(clnt);
1071
1072         v9fs_put_trans(clnt->trans_mod);
1073
1074         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
1075                 pr_info("Found fid %d not clunked\n", fid->fid);
1076                 p9_fid_destroy(fid);
1077         }
1078
1079         if (clnt->fidpool)
1080                 p9_idpool_destroy(clnt->fidpool);
1081
1082         p9_tag_cleanup(clnt);
1083
1084         kfree(clnt);
1085 }
1086 EXPORT_SYMBOL(p9_client_destroy);
1087
1088 void p9_client_disconnect(struct p9_client *clnt)
1089 {
1090         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1091         clnt->status = Disconnected;
1092 }
1093 EXPORT_SYMBOL(p9_client_disconnect);
1094
1095 void p9_client_begin_disconnect(struct p9_client *clnt)
1096 {
1097         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1098         clnt->status = BeginDisconnect;
1099 }
1100 EXPORT_SYMBOL(p9_client_begin_disconnect);
1101
1102 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1103         char *uname, u32 n_uname, char *aname)
1104 {
1105         int err = 0;
1106         struct p9_req_t *req;
1107         struct p9_fid *fid;
1108         struct p9_qid qid;
1109
1110
1111         p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1112                  afid ? afid->fid : -1, uname, aname);
1113         fid = p9_fid_create(clnt);
1114         if (IS_ERR(fid)) {
1115                 err = PTR_ERR(fid);
1116                 fid = NULL;
1117                 goto error;
1118         }
1119
1120         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
1121                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1122         if (IS_ERR(req)) {
1123                 err = PTR_ERR(req);
1124                 goto error;
1125         }
1126
1127         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
1128         if (err) {
1129                 trace_9p_protocol_dump(clnt, req->rc);
1130                 p9_free_req(clnt, req);
1131                 goto error;
1132         }
1133
1134         p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1135                  qid.type, (unsigned long long)qid.path, qid.version);
1136
1137         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1138
1139         p9_free_req(clnt, req);
1140         return fid;
1141
1142 error:
1143         if (fid)
1144                 p9_fid_destroy(fid);
1145         return ERR_PTR(err);
1146 }
1147 EXPORT_SYMBOL(p9_client_attach);
1148
1149 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1150                 char **wnames, int clone)
1151 {
1152         int err;
1153         struct p9_client *clnt;
1154         struct p9_fid *fid;
1155         struct p9_qid *wqids;
1156         struct p9_req_t *req;
1157         uint16_t nwqids, count;
1158
1159         err = 0;
1160         wqids = NULL;
1161         clnt = oldfid->clnt;
1162         if (clone) {
1163                 fid = p9_fid_create(clnt);
1164                 if (IS_ERR(fid)) {
1165                         err = PTR_ERR(fid);
1166                         fid = NULL;
1167                         goto error;
1168                 }
1169
1170                 fid->uid = oldfid->uid;
1171         } else
1172                 fid = oldfid;
1173
1174
1175         p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1176                  oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1177
1178         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1179                                                                 nwname, wnames);
1180         if (IS_ERR(req)) {
1181                 err = PTR_ERR(req);
1182                 goto error;
1183         }
1184
1185         err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1186         if (err) {
1187                 trace_9p_protocol_dump(clnt, req->rc);
1188                 p9_free_req(clnt, req);
1189                 goto clunk_fid;
1190         }
1191         p9_free_req(clnt, req);
1192
1193         p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1194
1195         if (nwqids != nwname) {
1196                 err = -ENOENT;
1197                 goto clunk_fid;
1198         }
1199
1200         for (count = 0; count < nwqids; count++)
1201                 p9_debug(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
1202                         count, wqids[count].type,
1203                         (unsigned long long)wqids[count].path,
1204                         wqids[count].version);
1205
1206         if (nwname)
1207                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1208         else
1209                 fid->qid = oldfid->qid;
1210
1211         kfree(wqids);
1212         return fid;
1213
1214 clunk_fid:
1215         kfree(wqids);
1216         p9_client_clunk(fid);
1217         fid = NULL;
1218
1219 error:
1220         if (fid && (fid != oldfid))
1221                 p9_fid_destroy(fid);
1222
1223         return ERR_PTR(err);
1224 }
1225 EXPORT_SYMBOL(p9_client_walk);
1226
1227 int p9_client_open(struct p9_fid *fid, int mode)
1228 {
1229         int err;
1230         struct p9_client *clnt;
1231         struct p9_req_t *req;
1232         struct p9_qid qid;
1233         int iounit;
1234
1235         clnt = fid->clnt;
1236         p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1237                 p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1238         err = 0;
1239
1240         if (fid->mode != -1)
1241                 return -EINVAL;
1242
1243         if (p9_is_proto_dotl(clnt))
1244                 req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1245         else
1246                 req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1247         if (IS_ERR(req)) {
1248                 err = PTR_ERR(req);
1249                 goto error;
1250         }
1251
1252         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1253         if (err) {
1254                 trace_9p_protocol_dump(clnt, req->rc);
1255                 goto free_and_error;
1256         }
1257
1258         p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1259                 p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1260                 (unsigned long long)qid.path, qid.version, iounit);
1261
1262         fid->mode = mode;
1263         fid->iounit = iounit;
1264
1265 free_and_error:
1266         p9_free_req(clnt, req);
1267 error:
1268         return err;
1269 }
1270 EXPORT_SYMBOL(p9_client_open);
1271
1272 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
1273                 gid_t gid, struct p9_qid *qid)
1274 {
1275         int err = 0;
1276         struct p9_client *clnt;
1277         struct p9_req_t *req;
1278         int iounit;
1279
1280         p9_debug(P9_DEBUG_9P,
1281                         ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1282                         ofid->fid, name, flags, mode, gid);
1283         clnt = ofid->clnt;
1284
1285         if (ofid->mode != -1)
1286                 return -EINVAL;
1287
1288         req = p9_client_rpc(clnt, P9_TLCREATE, "dsddd", ofid->fid, name, flags,
1289                         mode, gid);
1290         if (IS_ERR(req)) {
1291                 err = PTR_ERR(req);
1292                 goto error;
1293         }
1294
1295         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1296         if (err) {
1297                 trace_9p_protocol_dump(clnt, req->rc);
1298                 goto free_and_error;
1299         }
1300
1301         p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1302                         qid->type,
1303                         (unsigned long long)qid->path,
1304                         qid->version, iounit);
1305
1306         ofid->mode = mode;
1307         ofid->iounit = iounit;
1308
1309 free_and_error:
1310         p9_free_req(clnt, req);
1311 error:
1312         return err;
1313 }
1314 EXPORT_SYMBOL(p9_client_create_dotl);
1315
1316 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1317                      char *extension)
1318 {
1319         int err;
1320         struct p9_client *clnt;
1321         struct p9_req_t *req;
1322         struct p9_qid qid;
1323         int iounit;
1324
1325         p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1326                                                 fid->fid, name, perm, mode);
1327         err = 0;
1328         clnt = fid->clnt;
1329
1330         if (fid->mode != -1)
1331                 return -EINVAL;
1332
1333         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1334                                 mode, extension);
1335         if (IS_ERR(req)) {
1336                 err = PTR_ERR(req);
1337                 goto error;
1338         }
1339
1340         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1341         if (err) {
1342                 trace_9p_protocol_dump(clnt, req->rc);
1343                 goto free_and_error;
1344         }
1345
1346         p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1347                                 qid.type,
1348                                 (unsigned long long)qid.path,
1349                                 qid.version, iounit);
1350
1351         fid->mode = mode;
1352         fid->iounit = iounit;
1353
1354 free_and_error:
1355         p9_free_req(clnt, req);
1356 error:
1357         return err;
1358 }
1359 EXPORT_SYMBOL(p9_client_fcreate);
1360
1361 int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, gid_t gid,
1362                 struct p9_qid *qid)
1363 {
1364         int err = 0;
1365         struct p9_client *clnt;
1366         struct p9_req_t *req;
1367
1368         p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1369                         dfid->fid, name, symtgt);
1370         clnt = dfid->clnt;
1371
1372         req = p9_client_rpc(clnt, P9_TSYMLINK, "dssd", dfid->fid, name, symtgt,
1373                         gid);
1374         if (IS_ERR(req)) {
1375                 err = PTR_ERR(req);
1376                 goto error;
1377         }
1378
1379         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1380         if (err) {
1381                 trace_9p_protocol_dump(clnt, req->rc);
1382                 goto free_and_error;
1383         }
1384
1385         p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1386                         qid->type, (unsigned long long)qid->path, qid->version);
1387
1388 free_and_error:
1389         p9_free_req(clnt, req);
1390 error:
1391         return err;
1392 }
1393 EXPORT_SYMBOL(p9_client_symlink);
1394
1395 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
1396 {
1397         struct p9_client *clnt;
1398         struct p9_req_t *req;
1399
1400         p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1401                         dfid->fid, oldfid->fid, newname);
1402         clnt = dfid->clnt;
1403         req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1404                         newname);
1405         if (IS_ERR(req))
1406                 return PTR_ERR(req);
1407
1408         p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
1409         p9_free_req(clnt, req);
1410         return 0;
1411 }
1412 EXPORT_SYMBOL(p9_client_link);
1413
1414 int p9_client_fsync(struct p9_fid *fid, int datasync)
1415 {
1416         int err;
1417         struct p9_client *clnt;
1418         struct p9_req_t *req;
1419
1420         p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1421                         fid->fid, datasync);
1422         err = 0;
1423         clnt = fid->clnt;
1424
1425         req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1426         if (IS_ERR(req)) {
1427                 err = PTR_ERR(req);
1428                 goto error;
1429         }
1430
1431         p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1432
1433         p9_free_req(clnt, req);
1434
1435 error:
1436         return err;
1437 }
1438 EXPORT_SYMBOL(p9_client_fsync);
1439
1440 int p9_client_clunk(struct p9_fid *fid)
1441 {
1442         int err;
1443         struct p9_client *clnt;
1444         struct p9_req_t *req;
1445         int retries = 0;
1446
1447         if (!fid) {
1448                 pr_warn("%s (%d): Trying to clunk with NULL fid\n",
1449                         __func__, task_pid_nr(current));
1450                 dump_stack();
1451                 return 0;
1452         }
1453
1454 again:
1455         p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n", fid->fid,
1456                                                                 retries);
1457         err = 0;
1458         clnt = fid->clnt;
1459
1460         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1461         if (IS_ERR(req)) {
1462                 err = PTR_ERR(req);
1463                 goto error;
1464         }
1465
1466         p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1467
1468         p9_free_req(clnt, req);
1469 error:
1470         /*
1471          * Fid is not valid even after a failed clunk
1472          * If interrupted, retry once then give up and
1473          * leak fid until umount.
1474          */
1475         if (err == -ERESTARTSYS) {
1476                 if (retries++ == 0)
1477                         goto again;
1478         } else
1479                 p9_fid_destroy(fid);
1480         return err;
1481 }
1482 EXPORT_SYMBOL(p9_client_clunk);
1483
1484 int p9_client_remove(struct p9_fid *fid)
1485 {
1486         int err;
1487         struct p9_client *clnt;
1488         struct p9_req_t *req;
1489
1490         p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1491         err = 0;
1492         clnt = fid->clnt;
1493
1494         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1495         if (IS_ERR(req)) {
1496                 err = PTR_ERR(req);
1497                 goto error;
1498         }
1499
1500         p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1501
1502         p9_free_req(clnt, req);
1503 error:
1504         if (err == -ERESTARTSYS)
1505                 p9_client_clunk(fid);
1506         else
1507                 p9_fid_destroy(fid);
1508         return err;
1509 }
1510 EXPORT_SYMBOL(p9_client_remove);
1511
1512 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1513 {
1514         int err = 0;
1515         struct p9_req_t *req;
1516         struct p9_client *clnt;
1517
1518         p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1519                    dfid->fid, name, flags);
1520
1521         clnt = dfid->clnt;
1522         req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1523         if (IS_ERR(req)) {
1524                 err = PTR_ERR(req);
1525                 goto error;
1526         }
1527         p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1528
1529         p9_free_req(clnt, req);
1530 error:
1531         return err;
1532 }
1533 EXPORT_SYMBOL(p9_client_unlinkat);
1534
1535 int
1536 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1537                                                                 u32 count)
1538 {
1539         char *dataptr;
1540         int kernel_buf = 0;
1541         struct p9_req_t *req;
1542         struct p9_client *clnt;
1543         int err, rsize, non_zc = 0;
1544
1545
1546         p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
1547                    fid->fid, (unsigned long long) offset, count);
1548         err = 0;
1549         clnt = fid->clnt;
1550
1551         rsize = fid->iounit;
1552         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1553                 rsize = clnt->msize - P9_IOHDRSZ;
1554
1555         if (count < rsize)
1556                 rsize = count;
1557
1558         /* Don't bother zerocopy for small IO (< 1024) */
1559         if (clnt->trans_mod->zc_request && rsize > 1024) {
1560                 char *indata;
1561                 if (data) {
1562                         kernel_buf = 1;
1563                         indata = data;
1564                 } else
1565                         indata = (__force char *)udata;
1566                 /*
1567                  * response header len is 11
1568                  * PDU Header(7) + IO Size (4)
1569                  */
1570                 req = p9_client_zc_rpc(clnt, P9_TREAD, indata, NULL, rsize, 0,
1571                                        11, kernel_buf, "dqd", fid->fid,
1572                                        offset, rsize);
1573         } else {
1574                 non_zc = 1;
1575                 req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1576                                     rsize);
1577         }
1578         if (IS_ERR(req)) {
1579                 err = PTR_ERR(req);
1580                 goto error;
1581         }
1582
1583         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1584         if (err) {
1585                 trace_9p_protocol_dump(clnt, req->rc);
1586                 goto free_and_error;
1587         }
1588
1589         p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1590
1591         if (non_zc) {
1592                 if (data) {
1593                         memmove(data, dataptr, count);
1594                 } else {
1595                         err = copy_to_user(udata, dataptr, count);
1596                         if (err) {
1597                                 err = -EFAULT;
1598                                 goto free_and_error;
1599                         }
1600                 }
1601         }
1602         p9_free_req(clnt, req);
1603         return count;
1604
1605 free_and_error:
1606         p9_free_req(clnt, req);
1607 error:
1608         return err;
1609 }
1610 EXPORT_SYMBOL(p9_client_read);
1611
1612 int
1613 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1614                                                         u64 offset, u32 count)
1615 {
1616         int err, rsize;
1617         int kernel_buf = 0;
1618         struct p9_client *clnt;
1619         struct p9_req_t *req;
1620
1621         p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1622                                 fid->fid, (unsigned long long) offset, count);
1623         err = 0;
1624         clnt = fid->clnt;
1625
1626         rsize = fid->iounit;
1627         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1628                 rsize = clnt->msize - P9_IOHDRSZ;
1629
1630         if (count < rsize)
1631                 rsize = count;
1632
1633         /* Don't bother zerocopy for small IO (< 1024) */
1634         if (clnt->trans_mod->zc_request && rsize > 1024) {
1635                 char *odata;
1636                 if (data) {
1637                         kernel_buf = 1;
1638                         odata = data;
1639                 } else
1640                         odata = (char *)udata;
1641                 req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, odata, 0, rsize,
1642                                        P9_ZC_HDR_SZ, kernel_buf, "dqd",
1643                                        fid->fid, offset, rsize);
1644         } else {
1645                 if (data)
1646                         req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid,
1647                                             offset, rsize, data);
1648                 else
1649                         req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid,
1650                                             offset, rsize, udata);
1651         }
1652         if (IS_ERR(req)) {
1653                 err = PTR_ERR(req);
1654                 goto error;
1655         }
1656
1657         err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1658         if (err) {
1659                 trace_9p_protocol_dump(clnt, req->rc);
1660                 goto free_and_error;
1661         }
1662
1663         p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1664
1665         p9_free_req(clnt, req);
1666         return count;
1667
1668 free_and_error:
1669         p9_free_req(clnt, req);
1670 error:
1671         return err;
1672 }
1673 EXPORT_SYMBOL(p9_client_write);
1674
1675 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1676 {
1677         int err;
1678         struct p9_client *clnt;
1679         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1680         struct p9_req_t *req;
1681         u16 ignored;
1682
1683         p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1684
1685         if (!ret)
1686                 return ERR_PTR(-ENOMEM);
1687
1688         err = 0;
1689         clnt = fid->clnt;
1690
1691         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1692         if (IS_ERR(req)) {
1693                 err = PTR_ERR(req);
1694                 goto error;
1695         }
1696
1697         err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1698         if (err) {
1699                 trace_9p_protocol_dump(clnt, req->rc);
1700                 p9_free_req(clnt, req);
1701                 goto error;
1702         }
1703
1704         p9_debug(P9_DEBUG_9P,
1705                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1706                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1707                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1708                 "<<<    uid=%d gid=%d n_muid=%d\n",
1709                 ret->size, ret->type, ret->dev, ret->qid.type,
1710                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1711                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1712                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1713                 ret->n_uid, ret->n_gid, ret->n_muid);
1714
1715         p9_free_req(clnt, req);
1716         return ret;
1717
1718 error:
1719         kfree(ret);
1720         return ERR_PTR(err);
1721 }
1722 EXPORT_SYMBOL(p9_client_stat);
1723
1724 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1725                                                         u64 request_mask)
1726 {
1727         int err;
1728         struct p9_client *clnt;
1729         struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1730                                                                 GFP_KERNEL);
1731         struct p9_req_t *req;
1732
1733         p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1734                                                         fid->fid, request_mask);
1735
1736         if (!ret)
1737                 return ERR_PTR(-ENOMEM);
1738
1739         err = 0;
1740         clnt = fid->clnt;
1741
1742         req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1743         if (IS_ERR(req)) {
1744                 err = PTR_ERR(req);
1745                 goto error;
1746         }
1747
1748         err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1749         if (err) {
1750                 trace_9p_protocol_dump(clnt, req->rc);
1751                 p9_free_req(clnt, req);
1752                 goto error;
1753         }
1754
1755         p9_debug(P9_DEBUG_9P,
1756                 "<<< RGETATTR st_result_mask=%lld\n"
1757                 "<<< qid=%x.%llx.%x\n"
1758                 "<<< st_mode=%8.8x st_nlink=%llu\n"
1759                 "<<< st_uid=%d st_gid=%d\n"
1760                 "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1761                 "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1762                 "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1763                 "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1764                 "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1765                 "<<< st_gen=%lld st_data_version=%lld",
1766                 ret->st_result_mask, ret->qid.type, ret->qid.path,
1767                 ret->qid.version, ret->st_mode, ret->st_nlink, ret->st_uid,
1768                 ret->st_gid, ret->st_rdev, ret->st_size, ret->st_blksize,
1769                 ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1770                 ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1771                 ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1772                 ret->st_gen, ret->st_data_version);
1773
1774         p9_free_req(clnt, req);
1775         return ret;
1776
1777 error:
1778         kfree(ret);
1779         return ERR_PTR(err);
1780 }
1781 EXPORT_SYMBOL(p9_client_getattr_dotl);
1782
1783 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1784 {
1785         int ret;
1786
1787         /* NOTE: size shouldn't include its own length */
1788         /* size[2] type[2] dev[4] qid[13] */
1789         /* mode[4] atime[4] mtime[4] length[8]*/
1790         /* name[s] uid[s] gid[s] muid[s] */
1791         ret = 2+4+13+4+4+4+8+2+2+2+2;
1792
1793         if (wst->name)
1794                 ret += strlen(wst->name);
1795         if (wst->uid)
1796                 ret += strlen(wst->uid);
1797         if (wst->gid)
1798                 ret += strlen(wst->gid);
1799         if (wst->muid)
1800                 ret += strlen(wst->muid);
1801
1802         if ((proto_version == p9_proto_2000u) ||
1803                 (proto_version == p9_proto_2000L)) {
1804                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1805                 if (wst->extension)
1806                         ret += strlen(wst->extension);
1807         }
1808
1809         return ret;
1810 }
1811
1812 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1813 {
1814         int err;
1815         struct p9_req_t *req;
1816         struct p9_client *clnt;
1817
1818         err = 0;
1819         clnt = fid->clnt;
1820         wst->size = p9_client_statsize(wst, clnt->proto_version);
1821         p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1822         p9_debug(P9_DEBUG_9P,
1823                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1824                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1825                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1826                 "     uid=%d gid=%d n_muid=%d\n",
1827                 wst->size, wst->type, wst->dev, wst->qid.type,
1828                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1829                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1830                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1831                 wst->n_uid, wst->n_gid, wst->n_muid);
1832
1833         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1834         if (IS_ERR(req)) {
1835                 err = PTR_ERR(req);
1836                 goto error;
1837         }
1838
1839         p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1840
1841         p9_free_req(clnt, req);
1842 error:
1843         return err;
1844 }
1845 EXPORT_SYMBOL(p9_client_wstat);
1846
1847 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1848 {
1849         int err;
1850         struct p9_req_t *req;
1851         struct p9_client *clnt;
1852
1853         err = 0;
1854         clnt = fid->clnt;
1855         p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1856         p9_debug(P9_DEBUG_9P,
1857                 "    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1858                 "    atime_sec=%lld atime_nsec=%lld\n"
1859                 "    mtime_sec=%lld mtime_nsec=%lld\n",
1860                 p9attr->valid, p9attr->mode, p9attr->uid, p9attr->gid,
1861                 p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1862                 p9attr->mtime_sec, p9attr->mtime_nsec);
1863
1864         req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1865
1866         if (IS_ERR(req)) {
1867                 err = PTR_ERR(req);
1868                 goto error;
1869         }
1870         p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1871         p9_free_req(clnt, req);
1872 error:
1873         return err;
1874 }
1875 EXPORT_SYMBOL(p9_client_setattr);
1876
1877 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1878 {
1879         int err;
1880         struct p9_req_t *req;
1881         struct p9_client *clnt;
1882
1883         err = 0;
1884         clnt = fid->clnt;
1885
1886         p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1887
1888         req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1889         if (IS_ERR(req)) {
1890                 err = PTR_ERR(req);
1891                 goto error;
1892         }
1893
1894         err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1895                 &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1896                 &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1897         if (err) {
1898                 trace_9p_protocol_dump(clnt, req->rc);
1899                 p9_free_req(clnt, req);
1900                 goto error;
1901         }
1902
1903         p9_debug(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1904                 "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1905                 "fsid %llu namelen %ld\n",
1906                 fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1907                 sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1908                 sb->fsid, (long int)sb->namelen);
1909
1910         p9_free_req(clnt, req);
1911 error:
1912         return err;
1913 }
1914 EXPORT_SYMBOL(p9_client_statfs);
1915
1916 int p9_client_rename(struct p9_fid *fid,
1917                      struct p9_fid *newdirfid, const char *name)
1918 {
1919         int err;
1920         struct p9_req_t *req;
1921         struct p9_client *clnt;
1922
1923         err = 0;
1924         clnt = fid->clnt;
1925
1926         p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1927                         fid->fid, newdirfid->fid, name);
1928
1929         req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1930                         newdirfid->fid, name);
1931         if (IS_ERR(req)) {
1932                 err = PTR_ERR(req);
1933                 goto error;
1934         }
1935
1936         p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1937
1938         p9_free_req(clnt, req);
1939 error:
1940         return err;
1941 }
1942 EXPORT_SYMBOL(p9_client_rename);
1943
1944 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1945                        struct p9_fid *newdirfid, const char *new_name)
1946 {
1947         int err;
1948         struct p9_req_t *req;
1949         struct p9_client *clnt;
1950
1951         err = 0;
1952         clnt = olddirfid->clnt;
1953
1954         p9_debug(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1955                    " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1956                    newdirfid->fid, new_name);
1957
1958         req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1959                             old_name, newdirfid->fid, new_name);
1960         if (IS_ERR(req)) {
1961                 err = PTR_ERR(req);
1962                 goto error;
1963         }
1964
1965         p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
1966                    newdirfid->fid, new_name);
1967
1968         p9_free_req(clnt, req);
1969 error:
1970         return err;
1971 }
1972 EXPORT_SYMBOL(p9_client_renameat);
1973
1974 /*
1975  * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1976  */
1977 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1978                                 const char *attr_name, u64 *attr_size)
1979 {
1980         int err;
1981         struct p9_req_t *req;
1982         struct p9_client *clnt;
1983         struct p9_fid *attr_fid;
1984
1985         err = 0;
1986         clnt = file_fid->clnt;
1987         attr_fid = p9_fid_create(clnt);
1988         if (IS_ERR(attr_fid)) {
1989                 err = PTR_ERR(attr_fid);
1990                 attr_fid = NULL;
1991                 goto error;
1992         }
1993         p9_debug(P9_DEBUG_9P,
1994                 ">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
1995                 file_fid->fid, attr_fid->fid, attr_name);
1996
1997         req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
1998                         file_fid->fid, attr_fid->fid, attr_name);
1999         if (IS_ERR(req)) {
2000                 err = PTR_ERR(req);
2001                 goto error;
2002         }
2003         err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
2004         if (err) {
2005                 trace_9p_protocol_dump(clnt, req->rc);
2006                 p9_free_req(clnt, req);
2007                 goto clunk_fid;
2008         }
2009         p9_free_req(clnt, req);
2010         p9_debug(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
2011                 attr_fid->fid, *attr_size);
2012         return attr_fid;
2013 clunk_fid:
2014         p9_client_clunk(attr_fid);
2015         attr_fid = NULL;
2016 error:
2017         if (attr_fid && (attr_fid != file_fid))
2018                 p9_fid_destroy(attr_fid);
2019
2020         return ERR_PTR(err);
2021 }
2022 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
2023
2024 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
2025                         u64 attr_size, int flags)
2026 {
2027         int err;
2028         struct p9_req_t *req;
2029         struct p9_client *clnt;
2030
2031         p9_debug(P9_DEBUG_9P,
2032                 ">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
2033                 fid->fid, name, (long long)attr_size, flags);
2034         err = 0;
2035         clnt = fid->clnt;
2036         req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2037                         fid->fid, name, attr_size, flags);
2038         if (IS_ERR(req)) {
2039                 err = PTR_ERR(req);
2040                 goto error;
2041         }
2042         p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2043         p9_free_req(clnt, req);
2044 error:
2045         return err;
2046 }
2047 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2048
2049 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2050 {
2051         int err, rsize, non_zc = 0;
2052         struct p9_client *clnt;
2053         struct p9_req_t *req;
2054         char *dataptr;
2055
2056         p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2057                                 fid->fid, (unsigned long long) offset, count);
2058
2059         err = 0;
2060         clnt = fid->clnt;
2061
2062         rsize = fid->iounit;
2063         if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2064                 rsize = clnt->msize - P9_READDIRHDRSZ;
2065
2066         if (count < rsize)
2067                 rsize = count;
2068
2069         /* Don't bother zerocopy for small IO (< 1024) */
2070         if (clnt->trans_mod->zc_request && rsize > 1024) {
2071                 /*
2072                  * response header len is 11
2073                  * PDU Header(7) + IO Size (4)
2074                  */
2075                 req = p9_client_zc_rpc(clnt, P9_TREADDIR, data, NULL, rsize, 0,
2076                                        11, 1, "dqd", fid->fid, offset, rsize);
2077         } else {
2078                 non_zc = 1;
2079                 req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2080                                     offset, rsize);
2081         }
2082         if (IS_ERR(req)) {
2083                 err = PTR_ERR(req);
2084                 goto error;
2085         }
2086
2087         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2088         if (err) {
2089                 trace_9p_protocol_dump(clnt, req->rc);
2090                 goto free_and_error;
2091         }
2092
2093         p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2094
2095         if (non_zc)
2096                 memmove(data, dataptr, count);
2097
2098         p9_free_req(clnt, req);
2099         return count;
2100
2101 free_and_error:
2102         p9_free_req(clnt, req);
2103 error:
2104         return err;
2105 }
2106 EXPORT_SYMBOL(p9_client_readdir);
2107
2108 int p9_client_mknod_dotl(struct p9_fid *fid, char *name, int mode,
2109                         dev_t rdev, gid_t gid, struct p9_qid *qid)
2110 {
2111         int err;
2112         struct p9_client *clnt;
2113         struct p9_req_t *req;
2114
2115         err = 0;
2116         clnt = fid->clnt;
2117         p9_debug(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2118                 "minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2119         req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddd", fid->fid, name, mode,
2120                 MAJOR(rdev), MINOR(rdev), gid);
2121         if (IS_ERR(req))
2122                 return PTR_ERR(req);
2123
2124         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2125         if (err) {
2126                 trace_9p_protocol_dump(clnt, req->rc);
2127                 goto error;
2128         }
2129         p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2130                                 (unsigned long long)qid->path, qid->version);
2131
2132 error:
2133         p9_free_req(clnt, req);
2134         return err;
2135
2136 }
2137 EXPORT_SYMBOL(p9_client_mknod_dotl);
2138
2139 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
2140                                 gid_t gid, struct p9_qid *qid)
2141 {
2142         int err;
2143         struct p9_client *clnt;
2144         struct p9_req_t *req;
2145
2146         err = 0;
2147         clnt = fid->clnt;
2148         p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2149                  fid->fid, name, mode, gid);
2150         req = p9_client_rpc(clnt, P9_TMKDIR, "dsdd", fid->fid, name, mode,
2151                 gid);
2152         if (IS_ERR(req))
2153                 return PTR_ERR(req);
2154
2155         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2156         if (err) {
2157                 trace_9p_protocol_dump(clnt, req->rc);
2158                 goto error;
2159         }
2160         p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2161                                 (unsigned long long)qid->path, qid->version);
2162
2163 error:
2164         p9_free_req(clnt, req);
2165         return err;
2166
2167 }
2168 EXPORT_SYMBOL(p9_client_mkdir_dotl);
2169
2170 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2171 {
2172         int err;
2173         struct p9_client *clnt;
2174         struct p9_req_t *req;
2175
2176         err = 0;
2177         clnt = fid->clnt;
2178         p9_debug(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2179                         "start %lld length %lld proc_id %d client_id %s\n",
2180                         fid->fid, flock->type, flock->flags, flock->start,
2181                         flock->length, flock->proc_id, flock->client_id);
2182
2183         req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2184                                 flock->flags, flock->start, flock->length,
2185                                         flock->proc_id, flock->client_id);
2186
2187         if (IS_ERR(req))
2188                 return PTR_ERR(req);
2189
2190         err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2191         if (err) {
2192                 trace_9p_protocol_dump(clnt, req->rc);
2193                 goto error;
2194         }
2195         p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2196 error:
2197         p9_free_req(clnt, req);
2198         return err;
2199
2200 }
2201 EXPORT_SYMBOL(p9_client_lock_dotl);
2202
2203 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
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, ">>> TGETLOCK fid %d, type %i start %lld "
2212                 "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2213                 glock->start, glock->length, glock->proc_id, glock->client_id);
2214
2215         req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
2216                 glock->start, glock->length, glock->proc_id, glock->client_id);
2217
2218         if (IS_ERR(req))
2219                 return PTR_ERR(req);
2220
2221         err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2222                         &glock->start, &glock->length, &glock->proc_id,
2223                         &glock->client_id);
2224         if (err) {
2225                 trace_9p_protocol_dump(clnt, req->rc);
2226                 goto error;
2227         }
2228         p9_debug(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2229                 "proc_id %d client_id %s\n", glock->type, glock->start,
2230                 glock->length, glock->proc_id, glock->client_id);
2231 error:
2232         p9_free_req(clnt, req);
2233         return err;
2234 }
2235 EXPORT_SYMBOL(p9_client_getlock_dotl);
2236
2237 int p9_client_readlink(struct p9_fid *fid, char **target)
2238 {
2239         int err;
2240         struct p9_client *clnt;
2241         struct p9_req_t *req;
2242
2243         err = 0;
2244         clnt = fid->clnt;
2245         p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2246
2247         req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2248         if (IS_ERR(req))
2249                 return PTR_ERR(req);
2250
2251         err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2252         if (err) {
2253                 trace_9p_protocol_dump(clnt, req->rc);
2254                 goto error;
2255         }
2256         p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2257 error:
2258         p9_free_req(clnt, req);
2259         return err;
2260 }
2261 EXPORT_SYMBOL(p9_client_readlink);