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 again:
 744         /* Wait for the response */
 745         err = wait_event_interruptible(*req->wq,
 746                                        req->status >= REQ_STATUS_RCVD);
 747
 748         if ((err == -ERESTARTSYS) && (c->status == Connected)
 749                                   && (type == P9_TFLUSH)) {
 750                 sigpending = 1;
 751                 clear_thread_flag(TIF_SIGPENDING);
 752                 goto again;
 753         }
 754
 755         if (req->status == REQ_STATUS_ERROR) {
 756                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 757                 err = req->t_err;
 758         }
 759         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 760                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 761                 sigpending = 1;
 762                 clear_thread_flag(TIF_SIGPENDING);
 763
 764                 if (c->trans_mod->cancel(c, req))
 765                         p9_client_flush(c, req);
 766
 767                 /* if we received the response anyway, don't signal error */
 768                 if (req->status == REQ_STATUS_RCVD)
 769                         err = 0;
 770         }
 771         if (sigpending) {
 772                 spin_lock_irqsave(&current->sighand->siglock, flags);
 773                 recalc_sigpending();
 774                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 775         }
 776         if (err < 0)
 777                 goto reterr;
 778
 779         err = p9_check_errors(c, req);
 780         trace_9p_client_res(c, type, req->rc->tag, err);
 781         if (!err)
 782                 return req;
 783 reterr:
 784         p9_free_req(c, req);
 785         return ERR_PTR(err);
 786 }
 787
 788 /**
 789  * p9_client_zc_rpc - issue a request and wait for a response
 790  * @c: client session
 791  * @type: type of request
 792  * @uidata: user bffer that should be ued for zero copy read
 793  * @uodata: user buffer that shoud be user for zero copy write
 794  * @inlen: read buffer size
 795  * @olen: write buffer size
 796  * @hdrlen: reader header size, This is the size of response protocol data
 797  * @fmt: protocol format string (see protocol.c)
 798  *
 799  * Returns request structure (which client must free using p9_free_req)
 800  */
 801 static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
 802                                          char *uidata, char *uodata,
 803                                          int inlen, int olen, int in_hdrlen,
 804                                          int kern_buf, const char *fmt, ...)
 805 {
 806         va_list ap;
 807         int sigpending, err;
 808         unsigned long flags;
 809         struct p9_req_t *req;
 810
 811         va_start(ap, fmt);
 812         /*
 813          * We allocate a inline protocol data of only 4k bytes.
 814          * The actual content is passed in zero-copy fashion.
 815          */
 816         req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, fmt, ap);
 817         va_end(ap);
 818         if (IS_ERR(req))
 819                 return req;
 820
 821         if (signal_pending(current)) {
 822                 sigpending = 1;
 823                 clear_thread_flag(TIF_SIGPENDING);
 824         } else
 825                 sigpending = 0;
 826
 827         /* If we are called with KERNEL_DS force kern_buf */
 828         if (segment_eq(get_fs(), KERNEL_DS))
 829                 kern_buf = 1;
 830
 831         err = c->trans_mod->zc_request(c, req, uidata, uodata,
 832                                        inlen, olen, in_hdrlen, kern_buf);
 833         if (err < 0) {
 834                 if (err == -EIO)
 835                         c->status = Disconnected;
 836                 goto reterr;
 837         }
 838         if (req->status == REQ_STATUS_ERROR) {
 839                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 840                 err = req->t_err;
 841         }
 842         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 843                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 844                 sigpending = 1;
 845                 clear_thread_flag(TIF_SIGPENDING);
 846
 847                 if (c->trans_mod->cancel(c, req))
 848                         p9_client_flush(c, req);
 849
 850                 /* if we received the response anyway, don't signal error */
 851                 if (req->status == REQ_STATUS_RCVD)
 852                         err = 0;
 853         }
 854         if (sigpending) {
 855                 spin_lock_irqsave(&current->sighand->siglock, flags);
 856                 recalc_sigpending();
 857                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 858         }
 859         if (err < 0)
 860                 goto reterr;
 861
 862         err = p9_check_zc_errors(c, req, uidata, in_hdrlen, kern_buf);
 863         trace_9p_client_res(c, type, req->rc->tag, err);
 864         if (!err)
 865                 return req;
 866 reterr:
 867         p9_free_req(c, req);
 868         return ERR_PTR(err);
 869 }
 870
 871 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 872 {
 873         int ret;
 874         struct p9_fid *fid;
 875         unsigned long flags;
 876
 877         p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt);
 878         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
 879         if (!fid)
 880                 return ERR_PTR(-ENOMEM);
 881
 882         ret = p9_idpool_get(clnt->fidpool);
 883         if (ret < 0) {
 884                 ret = -ENOSPC;
 885                 goto error;
 886         }
 887         fid->fid = ret;
 888
 889         memset(&fid->qid, 0, sizeof(struct p9_qid));
 890         fid->mode = -1;
 891         fid->uid = current_fsuid();
 892         fid->clnt = clnt;
 893         fid->rdir = NULL;
 894         spin_lock_irqsave(&clnt->lock, flags);
 895         list_add(&fid->flist, &clnt->fidlist);
 896         spin_unlock_irqrestore(&clnt->lock, flags);
 897
 898         return fid;
 899
 900 error:
 901         kfree(fid);
 902         return ERR_PTR(ret);
 903 }
 904
 905 static void p9_fid_destroy(struct p9_fid *fid)
 906 {
 907         struct p9_client *clnt;
 908         unsigned long flags;
 909
 910         p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
 911         clnt = fid->clnt;
 912         p9_idpool_put(fid->fid, clnt->fidpool);
 913         spin_lock_irqsave(&clnt->lock, flags);
 914         list_del(&fid->flist);
 915         spin_unlock_irqrestore(&clnt->lock, flags);
 916         kfree(fid->rdir);
 917         kfree(fid);
 918 }
 919
 920 static int p9_client_version(struct p9_client *c)
 921 {
 922         int err = 0;
 923         struct p9_req_t *req;
 924         char *version;
 925         int msize;
 926
 927         p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
 928                  c->msize, c->proto_version);
 929
 930         switch (c->proto_version) {
 931         case p9_proto_2000L:
 932                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 933                                         c->msize, "9P2000.L");
 934                 break;
 935         case p9_proto_2000u:
 936                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 937                                         c->msize, "9P2000.u");
 938                 break;
 939         case p9_proto_legacy:
 940                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 941                                         c->msize, "9P2000");
 942                 break;
 943         default:
 944                 return -EINVAL;
 945                 break;
 946         }
 947
 948         if (IS_ERR(req))
 949                 return PTR_ERR(req);
 950
 951         err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
 952         if (err) {
 953                 p9_debug(P9_DEBUG_9P, "version error %d\n", err);
 954                 trace_9p_protocol_dump(c, req->rc);
 955                 goto error;
 956         }
 957
 958         p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
 959         if (!strncmp(version, "9P2000.L", 8))
 960                 c->proto_version = p9_proto_2000L;
 961         else if (!strncmp(version, "9P2000.u", 8))
 962                 c->proto_version = p9_proto_2000u;
 963         else if (!strncmp(version, "9P2000", 6))
 964                 c->proto_version = p9_proto_legacy;
 965         else {
 966                 err = -EREMOTEIO;
 967                 goto error;
 968         }
 969
 970         if (msize < c->msize)
 971                 c->msize = msize;
 972
 973 error:
 974         kfree(version);
 975         p9_free_req(c, req);
 976
 977         return err;
 978 }
 979
 980 struct p9_client *p9_client_create(const char *dev_name, char *options)
 981 {
 982         int err;
 983         struct p9_client *clnt;
 984
 985         err = 0;
 986         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
 987         if (!clnt)
 988                 return ERR_PTR(-ENOMEM);
 989
 990         clnt->trans_mod = NULL;
 991         clnt->trans = NULL;
 992         spin_lock_init(&clnt->lock);
 993         INIT_LIST_HEAD(&clnt->fidlist);
 994
 995         err = p9_tag_init(clnt);
 996         if (err < 0)
 997                 goto free_client;
 998
 999         err = parse_opts(options, clnt);
1000         if (err < 0)
1001                 goto destroy_tagpool;
1002
1003         if (!clnt->trans_mod)
1004                 clnt->trans_mod = v9fs_get_default_trans();
1005
1006         if (clnt->trans_mod == NULL) {
1007                 err = -EPROTONOSUPPORT;
1008                 p9_debug(P9_DEBUG_ERROR,
1009                          "No transport defined or default transport\n");
1010                 goto destroy_tagpool;
1011         }
1012
1013         clnt->fidpool = p9_idpool_create();
1014         if (IS_ERR(clnt->fidpool)) {
1015                 err = PTR_ERR(clnt->fidpool);
1016                 goto put_trans;
1017         }
1018
1019         p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1020                  clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1021
1022         err = clnt->trans_mod->create(clnt, dev_name, options);
1023         if (err)
1024                 goto destroy_fidpool;
1025
1026         if (clnt->msize > clnt->trans_mod->maxsize)
1027                 clnt->msize = clnt->trans_mod->maxsize;
1028
1029         err = p9_client_version(clnt);
1030         if (err)
1031                 goto close_trans;
1032
1033         return clnt;
1034
1035 close_trans:
1036         clnt->trans_mod->close(clnt);
1037 destroy_fidpool:
1038         p9_idpool_destroy(clnt->fidpool);
1039 put_trans:
1040         v9fs_put_trans(clnt->trans_mod);
1041 destroy_tagpool:
1042         p9_idpool_destroy(clnt->tagpool);
1043 free_client:
1044         kfree(clnt);
1045         return ERR_PTR(err);
1046 }
1047 EXPORT_SYMBOL(p9_client_create);
1048
1049 void p9_client_destroy(struct p9_client *clnt)
1050 {
1051         struct p9_fid *fid, *fidptr;
1052
1053         p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
1054
1055         if (clnt->trans_mod)
1056                 clnt->trans_mod->close(clnt);
1057
1058         v9fs_put_trans(clnt->trans_mod);
1059
1060         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
1061                 pr_info("Found fid %d not clunked\n", fid->fid);
1062                 p9_fid_destroy(fid);
1063         }
1064
1065         if (clnt->fidpool)
1066                 p9_idpool_destroy(clnt->fidpool);
1067
1068         p9_tag_cleanup(clnt);
1069
1070         kfree(clnt);
1071 }
1072 EXPORT_SYMBOL(p9_client_destroy);
1073
1074 void p9_client_disconnect(struct p9_client *clnt)
1075 {
1076         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1077         clnt->status = Disconnected;
1078 }
1079 EXPORT_SYMBOL(p9_client_disconnect);
1080
1081 void p9_client_begin_disconnect(struct p9_client *clnt)
1082 {
1083         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1084         clnt->status = BeginDisconnect;
1085 }
1086 EXPORT_SYMBOL(p9_client_begin_disconnect);
1087
1088 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1089         char *uname, u32 n_uname, char *aname)
1090 {
1091         int err = 0;
1092         struct p9_req_t *req;
1093         struct p9_fid *fid;
1094         struct p9_qid qid;
1095
1096
1097         p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1098                  afid ? afid->fid : -1, uname, aname);
1099         fid = p9_fid_create(clnt);
1100         if (IS_ERR(fid)) {
1101                 err = PTR_ERR(fid);
1102                 fid = NULL;
1103                 goto error;
1104         }
1105
1106         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
1107                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1108         if (IS_ERR(req)) {
1109                 err = PTR_ERR(req);
1110                 goto error;
1111         }
1112
1113         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
1114         if (err) {
1115                 trace_9p_protocol_dump(clnt, req->rc);
1116                 p9_free_req(clnt, req);
1117                 goto error;
1118         }
1119
1120         p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1121                  qid.type, (unsigned long long)qid.path, qid.version);
1122
1123         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1124
1125         p9_free_req(clnt, req);
1126         return fid;
1127
1128 error:
1129         if (fid)
1130                 p9_fid_destroy(fid);
1131         return ERR_PTR(err);
1132 }
1133 EXPORT_SYMBOL(p9_client_attach);
1134
1135 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1136                 char **wnames, int clone)
1137 {
1138         int err;
1139         struct p9_client *clnt;
1140         struct p9_fid *fid;
1141         struct p9_qid *wqids;
1142         struct p9_req_t *req;
1143         uint16_t nwqids, count;
1144
1145         err = 0;
1146         wqids = NULL;
1147         clnt = oldfid->clnt;
1148         if (clone) {
1149                 fid = p9_fid_create(clnt);
1150                 if (IS_ERR(fid)) {
1151                         err = PTR_ERR(fid);
1152                         fid = NULL;
1153                         goto error;
1154                 }
1155
1156                 fid->uid = oldfid->uid;
1157         } else
1158                 fid = oldfid;
1159
1160
1161         p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1162                  oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1163
1164         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1165                                                                 nwname, wnames);
1166         if (IS_ERR(req)) {
1167                 err = PTR_ERR(req);
1168                 goto error;
1169         }
1170
1171         err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1172         if (err) {
1173                 trace_9p_protocol_dump(clnt, req->rc);
1174                 p9_free_req(clnt, req);
1175                 goto clunk_fid;
1176         }
1177         p9_free_req(clnt, req);
1178
1179         p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1180
1181         if (nwqids != nwname) {
1182                 err = -ENOENT;
1183                 goto clunk_fid;
1184         }
1185
1186         for (count = 0; count < nwqids; count++)
1187                 p9_debug(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
1188                         count, wqids[count].type,
1189                         (unsigned long long)wqids[count].path,
1190                         wqids[count].version);
1191
1192         if (nwname)
1193                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1194         else
1195                 fid->qid = oldfid->qid;
1196
1197         kfree(wqids);
1198         return fid;
1199
1200 clunk_fid:
1201         kfree(wqids);
1202         p9_client_clunk(fid);
1203         fid = NULL;
1204
1205 error:
1206         if (fid && (fid != oldfid))
1207                 p9_fid_destroy(fid);
1208
1209         return ERR_PTR(err);
1210 }
1211 EXPORT_SYMBOL(p9_client_walk);
1212
1213 int p9_client_open(struct p9_fid *fid, int mode)
1214 {
1215         int err;
1216         struct p9_client *clnt;
1217         struct p9_req_t *req;
1218         struct p9_qid qid;
1219         int iounit;
1220
1221         clnt = fid->clnt;
1222         p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1223                 p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1224         err = 0;
1225
1226         if (fid->mode != -1)
1227                 return -EINVAL;
1228
1229         if (p9_is_proto_dotl(clnt))
1230                 req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1231         else
1232                 req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1233         if (IS_ERR(req)) {
1234                 err = PTR_ERR(req);
1235                 goto error;
1236         }
1237
1238         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1239         if (err) {
1240                 trace_9p_protocol_dump(clnt, req->rc);
1241                 goto free_and_error;
1242         }
1243
1244         p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1245                 p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1246                 (unsigned long long)qid.path, qid.version, iounit);
1247
1248         fid->mode = mode;
1249         fid->iounit = iounit;
1250
1251 free_and_error:
1252         p9_free_req(clnt, req);
1253 error:
1254         return err;
1255 }
1256 EXPORT_SYMBOL(p9_client_open);
1257
1258 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
1259                 gid_t gid, struct p9_qid *qid)
1260 {
1261         int err = 0;
1262         struct p9_client *clnt;
1263         struct p9_req_t *req;
1264         int iounit;
1265
1266         p9_debug(P9_DEBUG_9P,
1267                         ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1268                         ofid->fid, name, flags, mode, gid);
1269         clnt = ofid->clnt;
1270
1271         if (ofid->mode != -1)
1272                 return -EINVAL;
1273
1274         req = p9_client_rpc(clnt, P9_TLCREATE, "dsddd", ofid->fid, name, flags,
1275                         mode, gid);
1276         if (IS_ERR(req)) {
1277                 err = PTR_ERR(req);
1278                 goto error;
1279         }
1280
1281         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1282         if (err) {
1283                 trace_9p_protocol_dump(clnt, req->rc);
1284                 goto free_and_error;
1285         }
1286
1287         p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1288                         qid->type,
1289                         (unsigned long long)qid->path,
1290                         qid->version, iounit);
1291
1292         ofid->mode = mode;
1293         ofid->iounit = iounit;
1294
1295 free_and_error:
1296         p9_free_req(clnt, req);
1297 error:
1298         return err;
1299 }
1300 EXPORT_SYMBOL(p9_client_create_dotl);
1301
1302 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1303                      char *extension)
1304 {
1305         int err;
1306         struct p9_client *clnt;
1307         struct p9_req_t *req;
1308         struct p9_qid qid;
1309         int iounit;
1310
1311         p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1312                                                 fid->fid, name, perm, mode);
1313         err = 0;
1314         clnt = fid->clnt;
1315
1316         if (fid->mode != -1)
1317                 return -EINVAL;
1318
1319         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1320                                 mode, extension);
1321         if (IS_ERR(req)) {
1322                 err = PTR_ERR(req);
1323                 goto error;
1324         }
1325
1326         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1327         if (err) {
1328                 trace_9p_protocol_dump(clnt, req->rc);
1329                 goto free_and_error;
1330         }
1331
1332         p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1333                                 qid.type,
1334                                 (unsigned long long)qid.path,
1335                                 qid.version, iounit);
1336
1337         fid->mode = mode;
1338         fid->iounit = iounit;
1339
1340 free_and_error:
1341         p9_free_req(clnt, req);
1342 error:
1343         return err;
1344 }
1345 EXPORT_SYMBOL(p9_client_fcreate);
1346
1347 int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, gid_t gid,
1348                 struct p9_qid *qid)
1349 {
1350         int err = 0;
1351         struct p9_client *clnt;
1352         struct p9_req_t *req;
1353
1354         p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1355                         dfid->fid, name, symtgt);
1356         clnt = dfid->clnt;
1357
1358         req = p9_client_rpc(clnt, P9_TSYMLINK, "dssd", dfid->fid, name, symtgt,
1359                         gid);
1360         if (IS_ERR(req)) {
1361                 err = PTR_ERR(req);
1362                 goto error;
1363         }
1364
1365         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1366         if (err) {
1367                 trace_9p_protocol_dump(clnt, req->rc);
1368                 goto free_and_error;
1369         }
1370
1371         p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1372                         qid->type, (unsigned long long)qid->path, qid->version);
1373
1374 free_and_error:
1375         p9_free_req(clnt, req);
1376 error:
1377         return err;
1378 }
1379 EXPORT_SYMBOL(p9_client_symlink);
1380
1381 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
1382 {
1383         struct p9_client *clnt;
1384         struct p9_req_t *req;
1385
1386         p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1387                         dfid->fid, oldfid->fid, newname);
1388         clnt = dfid->clnt;
1389         req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1390                         newname);
1391         if (IS_ERR(req))
1392                 return PTR_ERR(req);
1393
1394         p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
1395         p9_free_req(clnt, req);
1396         return 0;
1397 }
1398 EXPORT_SYMBOL(p9_client_link);
1399
1400 int p9_client_fsync(struct p9_fid *fid, int datasync)
1401 {
1402         int err;
1403         struct p9_client *clnt;
1404         struct p9_req_t *req;
1405
1406         p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1407                         fid->fid, datasync);
1408         err = 0;
1409         clnt = fid->clnt;
1410
1411         req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1412         if (IS_ERR(req)) {
1413                 err = PTR_ERR(req);
1414                 goto error;
1415         }
1416
1417         p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1418
1419         p9_free_req(clnt, req);
1420
1421 error:
1422         return err;
1423 }
1424 EXPORT_SYMBOL(p9_client_fsync);
1425
1426 int p9_client_clunk(struct p9_fid *fid)
1427 {
1428         int err;
1429         struct p9_client *clnt;
1430         struct p9_req_t *req;
1431         int retries = 0;
1432
1433         if (!fid) {
1434                 pr_warn("%s (%d): Trying to clunk with NULL fid\n",
1435                         __func__, task_pid_nr(current));
1436                 dump_stack();
1437                 return 0;
1438         }
1439
1440 again:
1441         p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n", fid->fid,
1442                                                                 retries);
1443         err = 0;
1444         clnt = fid->clnt;
1445
1446         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1447         if (IS_ERR(req)) {
1448                 err = PTR_ERR(req);
1449                 goto error;
1450         }
1451
1452         p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1453
1454         p9_free_req(clnt, req);
1455 error:
1456         /*
1457          * Fid is not valid even after a failed clunk
1458          * If interrupted, retry once then give up and
1459          * leak fid until umount.
1460          */
1461         if (err == -ERESTARTSYS) {
1462                 if (retries++ == 0)
1463                         goto again;
1464         } else
1465                 p9_fid_destroy(fid);
1466         return err;
1467 }
1468 EXPORT_SYMBOL(p9_client_clunk);
1469
1470 int p9_client_remove(struct p9_fid *fid)
1471 {
1472         int err;
1473         struct p9_client *clnt;
1474         struct p9_req_t *req;
1475
1476         p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1477         err = 0;
1478         clnt = fid->clnt;
1479
1480         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1481         if (IS_ERR(req)) {
1482                 err = PTR_ERR(req);
1483                 goto error;
1484         }
1485
1486         p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1487
1488         p9_free_req(clnt, req);
1489 error:
1490         if (err == -ERESTARTSYS)
1491                 p9_client_clunk(fid);
1492         else
1493                 p9_fid_destroy(fid);
1494         return err;
1495 }
1496 EXPORT_SYMBOL(p9_client_remove);
1497
1498 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1499 {
1500         int err = 0;
1501         struct p9_req_t *req;
1502         struct p9_client *clnt;
1503
1504         p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1505                    dfid->fid, name, flags);
1506
1507         clnt = dfid->clnt;
1508         req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1509         if (IS_ERR(req)) {
1510                 err = PTR_ERR(req);
1511                 goto error;
1512         }
1513         p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1514
1515         p9_free_req(clnt, req);
1516 error:
1517         return err;
1518 }
1519 EXPORT_SYMBOL(p9_client_unlinkat);
1520
1521 int
1522 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1523                                                                 u32 count)
1524 {
1525         char *dataptr;
1526         int kernel_buf = 0;
1527         struct p9_req_t *req;
1528         struct p9_client *clnt;
1529         int err, rsize, non_zc = 0;
1530
1531
1532         p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
1533                    fid->fid, (unsigned long long) offset, count);
1534         err = 0;
1535         clnt = fid->clnt;
1536
1537         rsize = fid->iounit;
1538         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1539                 rsize = clnt->msize - P9_IOHDRSZ;
1540
1541         if (count < rsize)
1542                 rsize = count;
1543
1544         /* Don't bother zerocopy for small IO (< 1024) */
1545         if (clnt->trans_mod->zc_request && rsize > 1024) {
1546                 char *indata;
1547                 if (data) {
1548                         kernel_buf = 1;
1549                         indata = data;
1550                 } else
1551                         indata = (__force char *)udata;
1552                 /*
1553                  * response header len is 11
1554                  * PDU Header(7) + IO Size (4)
1555                  */
1556                 req = p9_client_zc_rpc(clnt, P9_TREAD, indata, NULL, rsize, 0,
1557                                        11, kernel_buf, "dqd", fid->fid,
1558                                        offset, rsize);
1559         } else {
1560                 non_zc = 1;
1561                 req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1562                                     rsize);
1563         }
1564         if (IS_ERR(req)) {
1565                 err = PTR_ERR(req);
1566                 goto error;
1567         }
1568
1569         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1570         if (err) {
1571                 trace_9p_protocol_dump(clnt, req->rc);
1572                 goto free_and_error;
1573         }
1574
1575         p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1576
1577         if (non_zc) {
1578                 if (data) {
1579                         memmove(data, dataptr, count);
1580                 } else {
1581                         err = copy_to_user(udata, dataptr, count);
1582                         if (err) {
1583                                 err = -EFAULT;
1584                                 goto free_and_error;
1585                         }
1586                 }
1587         }
1588         p9_free_req(clnt, req);
1589         return count;
1590
1591 free_and_error:
1592         p9_free_req(clnt, req);
1593 error:
1594         return err;
1595 }
1596 EXPORT_SYMBOL(p9_client_read);
1597
1598 int
1599 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1600                                                         u64 offset, u32 count)
1601 {
1602         int err, rsize;
1603         int kernel_buf = 0;
1604         struct p9_client *clnt;
1605         struct p9_req_t *req;
1606
1607         p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1608                                 fid->fid, (unsigned long long) offset, count);
1609         err = 0;
1610         clnt = fid->clnt;
1611
1612         rsize = fid->iounit;
1613         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1614                 rsize = clnt->msize - P9_IOHDRSZ;
1615
1616         if (count < rsize)
1617                 rsize = count;
1618
1619         /* Don't bother zerocopy for small IO (< 1024) */
1620         if (clnt->trans_mod->zc_request && rsize > 1024) {
1621                 char *odata;
1622                 if (data) {
1623                         kernel_buf = 1;
1624                         odata = data;
1625                 } else
1626                         odata = (char *)udata;
1627                 req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, odata, 0, rsize,
1628                                        P9_ZC_HDR_SZ, kernel_buf, "dqd",
1629                                        fid->fid, offset, rsize);
1630         } else {
1631                 if (data)
1632                         req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid,
1633                                             offset, rsize, data);
1634                 else
1635                         req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid,
1636                                             offset, rsize, udata);
1637         }
1638         if (IS_ERR(req)) {
1639                 err = PTR_ERR(req);
1640                 goto error;
1641         }
1642
1643         err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1644         if (err) {
1645                 trace_9p_protocol_dump(clnt, req->rc);
1646                 goto free_and_error;
1647         }
1648
1649         p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1650
1651         p9_free_req(clnt, req);
1652         return count;
1653
1654 free_and_error:
1655         p9_free_req(clnt, req);
1656 error:
1657         return err;
1658 }
1659 EXPORT_SYMBOL(p9_client_write);
1660
1661 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1662 {
1663         int err;
1664         struct p9_client *clnt;
1665         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1666         struct p9_req_t *req;
1667         u16 ignored;
1668
1669         p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1670
1671         if (!ret)
1672                 return ERR_PTR(-ENOMEM);
1673
1674         err = 0;
1675         clnt = fid->clnt;
1676
1677         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1678         if (IS_ERR(req)) {
1679                 err = PTR_ERR(req);
1680                 goto error;
1681         }
1682
1683         err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1684         if (err) {
1685                 trace_9p_protocol_dump(clnt, req->rc);
1686                 p9_free_req(clnt, req);
1687                 goto error;
1688         }
1689
1690         p9_debug(P9_DEBUG_9P,
1691                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1692                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1693                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1694                 "<<<    uid=%d gid=%d n_muid=%d\n",
1695                 ret->size, ret->type, ret->dev, ret->qid.type,
1696                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1697                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1698                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1699                 ret->n_uid, ret->n_gid, ret->n_muid);
1700
1701         p9_free_req(clnt, req);
1702         return ret;
1703
1704 error:
1705         kfree(ret);
1706         return ERR_PTR(err);
1707 }
1708 EXPORT_SYMBOL(p9_client_stat);
1709
1710 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1711                                                         u64 request_mask)
1712 {
1713         int err;
1714         struct p9_client *clnt;
1715         struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1716                                                                 GFP_KERNEL);
1717         struct p9_req_t *req;
1718
1719         p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1720                                                         fid->fid, request_mask);
1721
1722         if (!ret)
1723                 return ERR_PTR(-ENOMEM);
1724
1725         err = 0;
1726         clnt = fid->clnt;
1727
1728         req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1729         if (IS_ERR(req)) {
1730                 err = PTR_ERR(req);
1731                 goto error;
1732         }
1733
1734         err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1735         if (err) {
1736                 trace_9p_protocol_dump(clnt, req->rc);
1737                 p9_free_req(clnt, req);
1738                 goto error;
1739         }
1740
1741         p9_debug(P9_DEBUG_9P,
1742                 "<<< RGETATTR st_result_mask=%lld\n"
1743                 "<<< qid=%x.%llx.%x\n"
1744                 "<<< st_mode=%8.8x st_nlink=%llu\n"
1745                 "<<< st_uid=%d st_gid=%d\n"
1746                 "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1747                 "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1748                 "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1749                 "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1750                 "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1751                 "<<< st_gen=%lld st_data_version=%lld",
1752                 ret->st_result_mask, ret->qid.type, ret->qid.path,
1753                 ret->qid.version, ret->st_mode, ret->st_nlink, ret->st_uid,
1754                 ret->st_gid, ret->st_rdev, ret->st_size, ret->st_blksize,
1755                 ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1756                 ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1757                 ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1758                 ret->st_gen, ret->st_data_version);
1759
1760         p9_free_req(clnt, req);
1761         return ret;
1762
1763 error:
1764         kfree(ret);
1765         return ERR_PTR(err);
1766 }
1767 EXPORT_SYMBOL(p9_client_getattr_dotl);
1768
1769 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1770 {
1771         int ret;
1772
1773         /* NOTE: size shouldn't include its own length */
1774         /* size[2] type[2] dev[4] qid[13] */
1775         /* mode[4] atime[4] mtime[4] length[8]*/
1776         /* name[s] uid[s] gid[s] muid[s] */
1777         ret = 2+4+13+4+4+4+8+2+2+2+2;
1778
1779         if (wst->name)
1780                 ret += strlen(wst->name);
1781         if (wst->uid)
1782                 ret += strlen(wst->uid);
1783         if (wst->gid)
1784                 ret += strlen(wst->gid);
1785         if (wst->muid)
1786                 ret += strlen(wst->muid);
1787
1788         if ((proto_version == p9_proto_2000u) ||
1789                 (proto_version == p9_proto_2000L)) {
1790                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1791                 if (wst->extension)
1792                         ret += strlen(wst->extension);
1793         }
1794
1795         return ret;
1796 }
1797
1798 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1799 {
1800         int err;
1801         struct p9_req_t *req;
1802         struct p9_client *clnt;
1803
1804         err = 0;
1805         clnt = fid->clnt;
1806         wst->size = p9_client_statsize(wst, clnt->proto_version);
1807         p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1808         p9_debug(P9_DEBUG_9P,
1809                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1810                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1811                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1812                 "     uid=%d gid=%d n_muid=%d\n",
1813                 wst->size, wst->type, wst->dev, wst->qid.type,
1814                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1815                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1816                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1817                 wst->n_uid, wst->n_gid, wst->n_muid);
1818
1819         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1820         if (IS_ERR(req)) {
1821                 err = PTR_ERR(req);
1822                 goto error;
1823         }
1824
1825         p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1826
1827         p9_free_req(clnt, req);
1828 error:
1829         return err;
1830 }
1831 EXPORT_SYMBOL(p9_client_wstat);
1832
1833 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1834 {
1835         int err;
1836         struct p9_req_t *req;
1837         struct p9_client *clnt;
1838
1839         err = 0;
1840         clnt = fid->clnt;
1841         p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1842         p9_debug(P9_DEBUG_9P,
1843                 "    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1844                 "    atime_sec=%lld atime_nsec=%lld\n"
1845                 "    mtime_sec=%lld mtime_nsec=%lld\n",
1846                 p9attr->valid, p9attr->mode, p9attr->uid, p9attr->gid,
1847                 p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1848                 p9attr->mtime_sec, p9attr->mtime_nsec);
1849
1850         req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1851
1852         if (IS_ERR(req)) {
1853                 err = PTR_ERR(req);
1854                 goto error;
1855         }
1856         p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1857         p9_free_req(clnt, req);
1858 error:
1859         return err;
1860 }
1861 EXPORT_SYMBOL(p9_client_setattr);
1862
1863 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1864 {
1865         int err;
1866         struct p9_req_t *req;
1867         struct p9_client *clnt;
1868
1869         err = 0;
1870         clnt = fid->clnt;
1871
1872         p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1873
1874         req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1875         if (IS_ERR(req)) {
1876                 err = PTR_ERR(req);
1877                 goto error;
1878         }
1879
1880         err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1881                 &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1882                 &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1883         if (err) {
1884                 trace_9p_protocol_dump(clnt, req->rc);
1885                 p9_free_req(clnt, req);
1886                 goto error;
1887         }
1888
1889         p9_debug(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1890                 "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1891                 "fsid %llu namelen %ld\n",
1892                 fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1893                 sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1894                 sb->fsid, (long int)sb->namelen);
1895
1896         p9_free_req(clnt, req);
1897 error:
1898         return err;
1899 }
1900 EXPORT_SYMBOL(p9_client_statfs);
1901
1902 int p9_client_rename(struct p9_fid *fid,
1903                      struct p9_fid *newdirfid, const char *name)
1904 {
1905         int err;
1906         struct p9_req_t *req;
1907         struct p9_client *clnt;
1908
1909         err = 0;
1910         clnt = fid->clnt;
1911
1912         p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1913                         fid->fid, newdirfid->fid, name);
1914
1915         req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1916                         newdirfid->fid, name);
1917         if (IS_ERR(req)) {
1918                 err = PTR_ERR(req);
1919                 goto error;
1920         }
1921
1922         p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1923
1924         p9_free_req(clnt, req);
1925 error:
1926         return err;
1927 }
1928 EXPORT_SYMBOL(p9_client_rename);
1929
1930 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1931                        struct p9_fid *newdirfid, const char *new_name)
1932 {
1933         int err;
1934         struct p9_req_t *req;
1935         struct p9_client *clnt;
1936
1937         err = 0;
1938         clnt = olddirfid->clnt;
1939
1940         p9_debug(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1941                    " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1942                    newdirfid->fid, new_name);
1943
1944         req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1945                             old_name, newdirfid->fid, new_name);
1946         if (IS_ERR(req)) {
1947                 err = PTR_ERR(req);
1948                 goto error;
1949         }
1950
1951         p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
1952                    newdirfid->fid, new_name);
1953
1954         p9_free_req(clnt, req);
1955 error:
1956         return err;
1957 }
1958 EXPORT_SYMBOL(p9_client_renameat);
1959
1960 /*
1961  * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1962  */
1963 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1964                                 const char *attr_name, u64 *attr_size)
1965 {
1966         int err;
1967         struct p9_req_t *req;
1968         struct p9_client *clnt;
1969         struct p9_fid *attr_fid;
1970
1971         err = 0;
1972         clnt = file_fid->clnt;
1973         attr_fid = p9_fid_create(clnt);
1974         if (IS_ERR(attr_fid)) {
1975                 err = PTR_ERR(attr_fid);
1976                 attr_fid = NULL;
1977                 goto error;
1978         }
1979         p9_debug(P9_DEBUG_9P,
1980                 ">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
1981                 file_fid->fid, attr_fid->fid, attr_name);
1982
1983         req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
1984                         file_fid->fid, attr_fid->fid, attr_name);
1985         if (IS_ERR(req)) {
1986                 err = PTR_ERR(req);
1987                 goto error;
1988         }
1989         err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
1990         if (err) {
1991                 trace_9p_protocol_dump(clnt, req->rc);
1992                 p9_free_req(clnt, req);
1993                 goto clunk_fid;
1994         }
1995         p9_free_req(clnt, req);
1996         p9_debug(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
1997                 attr_fid->fid, *attr_size);
1998         return attr_fid;
1999 clunk_fid:
2000         p9_client_clunk(attr_fid);
2001         attr_fid = NULL;
2002 error:
2003         if (attr_fid && (attr_fid != file_fid))
2004                 p9_fid_destroy(attr_fid);
2005
2006         return ERR_PTR(err);
2007 }
2008 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
2009
2010 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
2011                         u64 attr_size, int flags)
2012 {
2013         int err;
2014         struct p9_req_t *req;
2015         struct p9_client *clnt;
2016
2017         p9_debug(P9_DEBUG_9P,
2018                 ">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
2019                 fid->fid, name, (long long)attr_size, flags);
2020         err = 0;
2021         clnt = fid->clnt;
2022         req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2023                         fid->fid, name, attr_size, flags);
2024         if (IS_ERR(req)) {
2025                 err = PTR_ERR(req);
2026                 goto error;
2027         }
2028         p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2029         p9_free_req(clnt, req);
2030 error:
2031         return err;
2032 }
2033 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2034
2035 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2036 {
2037         int err, rsize, non_zc = 0;
2038         struct p9_client *clnt;
2039         struct p9_req_t *req;
2040         char *dataptr;
2041
2042         p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2043                                 fid->fid, (unsigned long long) offset, count);
2044
2045         err = 0;
2046         clnt = fid->clnt;
2047
2048         rsize = fid->iounit;
2049         if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2050                 rsize = clnt->msize - P9_READDIRHDRSZ;
2051
2052         if (count < rsize)
2053                 rsize = count;
2054
2055         /* Don't bother zerocopy for small IO (< 1024) */
2056         if (clnt->trans_mod->zc_request && rsize > 1024) {
2057                 /*
2058                  * response header len is 11
2059                  * PDU Header(7) + IO Size (4)
2060                  */
2061                 req = p9_client_zc_rpc(clnt, P9_TREADDIR, data, NULL, rsize, 0,
2062                                        11, 1, "dqd", fid->fid, offset, rsize);
2063         } else {
2064                 non_zc = 1;
2065                 req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2066                                     offset, rsize);
2067         }
2068         if (IS_ERR(req)) {
2069                 err = PTR_ERR(req);
2070                 goto error;
2071         }
2072
2073         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2074         if (err) {
2075                 trace_9p_protocol_dump(clnt, req->rc);
2076                 goto free_and_error;
2077         }
2078
2079         p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2080
2081         if (non_zc)
2082                 memmove(data, dataptr, count);
2083
2084         p9_free_req(clnt, req);
2085         return count;
2086
2087 free_and_error:
2088         p9_free_req(clnt, req);
2089 error:
2090         return err;
2091 }
2092 EXPORT_SYMBOL(p9_client_readdir);
2093
2094 int p9_client_mknod_dotl(struct p9_fid *fid, char *name, int mode,
2095                         dev_t rdev, gid_t gid, struct p9_qid *qid)
2096 {
2097         int err;
2098         struct p9_client *clnt;
2099         struct p9_req_t *req;
2100
2101         err = 0;
2102         clnt = fid->clnt;
2103         p9_debug(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2104                 "minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2105         req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddd", fid->fid, name, mode,
2106                 MAJOR(rdev), MINOR(rdev), gid);
2107         if (IS_ERR(req))
2108                 return PTR_ERR(req);
2109
2110         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2111         if (err) {
2112                 trace_9p_protocol_dump(clnt, req->rc);
2113                 goto error;
2114         }
2115         p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2116                                 (unsigned long long)qid->path, qid->version);
2117
2118 error:
2119         p9_free_req(clnt, req);
2120         return err;
2121
2122 }
2123 EXPORT_SYMBOL(p9_client_mknod_dotl);
2124
2125 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
2126                                 gid_t gid, struct p9_qid *qid)
2127 {
2128         int err;
2129         struct p9_client *clnt;
2130         struct p9_req_t *req;
2131
2132         err = 0;
2133         clnt = fid->clnt;
2134         p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2135                  fid->fid, name, mode, gid);
2136         req = p9_client_rpc(clnt, P9_TMKDIR, "dsdd", fid->fid, name, mode,
2137                 gid);
2138         if (IS_ERR(req))
2139                 return PTR_ERR(req);
2140
2141         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2142         if (err) {
2143                 trace_9p_protocol_dump(clnt, req->rc);
2144                 goto error;
2145         }
2146         p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2147                                 (unsigned long long)qid->path, qid->version);
2148
2149 error:
2150         p9_free_req(clnt, req);
2151         return err;
2152
2153 }
2154 EXPORT_SYMBOL(p9_client_mkdir_dotl);
2155
2156 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2157 {
2158         int err;
2159         struct p9_client *clnt;
2160         struct p9_req_t *req;
2161
2162         err = 0;
2163         clnt = fid->clnt;
2164         p9_debug(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2165                         "start %lld length %lld proc_id %d client_id %s\n",
2166                         fid->fid, flock->type, flock->flags, flock->start,
2167                         flock->length, flock->proc_id, flock->client_id);
2168
2169         req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2170                                 flock->flags, flock->start, flock->length,
2171                                         flock->proc_id, flock->client_id);
2172
2173         if (IS_ERR(req))
2174                 return PTR_ERR(req);
2175
2176         err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2177         if (err) {
2178                 trace_9p_protocol_dump(clnt, req->rc);
2179                 goto error;
2180         }
2181         p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2182 error:
2183         p9_free_req(clnt, req);
2184         return err;
2185
2186 }
2187 EXPORT_SYMBOL(p9_client_lock_dotl);
2188
2189 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2190 {
2191         int err;
2192         struct p9_client *clnt;
2193         struct p9_req_t *req;
2194
2195         err = 0;
2196         clnt = fid->clnt;
2197         p9_debug(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
2198                 "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2199                 glock->start, glock->length, glock->proc_id, glock->client_id);
2200
2201         req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
2202                 glock->start, glock->length, glock->proc_id, glock->client_id);
2203
2204         if (IS_ERR(req))
2205                 return PTR_ERR(req);
2206
2207         err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2208                         &glock->start, &glock->length, &glock->proc_id,
2209                         &glock->client_id);
2210         if (err) {
2211                 trace_9p_protocol_dump(clnt, req->rc);
2212                 goto error;
2213         }
2214         p9_debug(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2215                 "proc_id %d client_id %s\n", glock->type, glock->start,
2216                 glock->length, glock->proc_id, glock->client_id);
2217 error:
2218         p9_free_req(clnt, req);
2219         return err;
2220 }
2221 EXPORT_SYMBOL(p9_client_getlock_dotl);
2222
2223 int p9_client_readlink(struct p9_fid *fid, char **target)
2224 {
2225         int err;
2226         struct p9_client *clnt;
2227         struct p9_req_t *req;
2228
2229         err = 0;
2230         clnt = fid->clnt;
2231         p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2232
2233         req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2234         if (IS_ERR(req))
2235                 return PTR_ERR(req);
2236
2237         err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2238         if (err) {
2239                 trace_9p_protocol_dump(clnt, req->rc);
2240                 goto error;
2241         }
2242         p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2243 error:
2244         p9_free_req(clnt, req);
2245         return err;
2246 }
2247 EXPORT_SYMBOL(p9_client_readlink);