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 /*
  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_2000L;
 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 struct p9_fcall *p9_fcall_alloc(int alloc_msize)
 208 {
 209         struct p9_fcall *fc;
 210         fc = kmalloc(sizeof(struct p9_fcall) + alloc_msize, GFP_NOFS);
 211         if (!fc)
 212                 return NULL;
 213         fc->capacity = alloc_msize;
 214         fc->sdata = (char *) fc + sizeof(struct p9_fcall);
 215         return fc;
 216 }
 217
 218 /**
 219  * p9_tag_alloc - lookup/allocate a request by tag
 220  * @c: client session to lookup tag within
 221  * @tag: numeric id for transaction
 222  *
 223  * this is a simple array lookup, but will grow the
 224  * request_slots as necessary to accommodate transaction
 225  * ids which did not previously have a slot.
 226  *
 227  * this code relies on the client spinlock to manage locks, its
 228  * possible we should switch to something else, but I'd rather
 229  * stick with something low-overhead for the common case.
 230  *
 231  */
 232
 233 static struct p9_req_t *
 234 p9_tag_alloc(struct p9_client *c, u16 tag, unsigned int max_size)
 235 {
 236         unsigned long flags;
 237         int row, col;
 238         struct p9_req_t *req;
 239         int alloc_msize = min(c->msize, max_size);
 240
 241         /* This looks up the original request by tag so we know which
 242          * buffer to read the data into */
 243         tag++;
 244
 245         if (tag >= c->max_tag) {
 246                 spin_lock_irqsave(&c->lock, flags);
 247                 /* check again since original check was outside of lock */
 248                 while (tag >= c->max_tag) {
 249                         row = (tag / P9_ROW_MAXTAG);
 250                         c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
 251                                         sizeof(struct p9_req_t), GFP_ATOMIC);
 252
 253                         if (!c->reqs[row]) {
 254                                 pr_err("Couldn't grow tag array\n");
 255                                 spin_unlock_irqrestore(&c->lock, flags);
 256                                 return ERR_PTR(-ENOMEM);
 257                         }
 258                         for (col = 0; col < P9_ROW_MAXTAG; col++) {
 259                                 c->reqs[row][col].status = REQ_STATUS_IDLE;
 260                                 c->reqs[row][col].tc = NULL;
 261                         }
 262                         c->max_tag += P9_ROW_MAXTAG;
 263                 }
 264                 spin_unlock_irqrestore(&c->lock, flags);
 265         }
 266         row = tag / P9_ROW_MAXTAG;
 267         col = tag % P9_ROW_MAXTAG;
 268
 269         req = &c->reqs[row][col];
 270         if (!req->wq) {
 271                 req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_NOFS);
 272                 if (!req->wq)
 273                         goto grow_failed;
 274                 init_waitqueue_head(req->wq);
 275         }
 276
 277         if (!req->tc)
 278                 req->tc = p9_fcall_alloc(alloc_msize);
 279         if (!req->rc)
 280                 req->rc = p9_fcall_alloc(alloc_msize);
 281         if (!req->tc || !req->rc)
 282                 goto grow_failed;
 283
 284         p9pdu_reset(req->tc);
 285         p9pdu_reset(req->rc);
 286
 287         req->tc->tag = tag-1;
 288         req->status = REQ_STATUS_ALLOC;
 289
 290         return req;
 291
 292 grow_failed:
 293         pr_err("Couldn't grow tag array\n");
 294         kfree(req->tc);
 295         kfree(req->rc);
 296         kfree(req->wq);
 297         req->tc = req->rc = NULL;
 298         req->wq = NULL;
 299         return ERR_PTR(-ENOMEM);
 300 }
 301
 302 /**
 303  * p9_tag_lookup - lookup a request by tag
 304  * @c: client session to lookup tag within
 305  * @tag: numeric id for transaction
 306  *
 307  */
 308
 309 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
 310 {
 311         int row, col;
 312
 313         /* This looks up the original request by tag so we know which
 314          * buffer to read the data into */
 315         tag++;
 316
 317         if(tag >= c->max_tag)
 318                 return NULL;
 319
 320         row = tag / P9_ROW_MAXTAG;
 321         col = tag % P9_ROW_MAXTAG;
 322
 323         return &c->reqs[row][col];
 324 }
 325 EXPORT_SYMBOL(p9_tag_lookup);
 326
 327 /**
 328  * p9_tag_init - setup tags structure and contents
 329  * @c:  v9fs client struct
 330  *
 331  * This initializes the tags structure for each client instance.
 332  *
 333  */
 334
 335 static int p9_tag_init(struct p9_client *c)
 336 {
 337         int err = 0;
 338
 339         c->tagpool = p9_idpool_create();
 340         if (IS_ERR(c->tagpool)) {
 341                 err = PTR_ERR(c->tagpool);
 342                 goto error;
 343         }
 344         err = p9_idpool_get(c->tagpool); /* reserve tag 0 */
 345         if (err < 0) {
 346                 p9_idpool_destroy(c->tagpool);
 347                 goto error;
 348         }
 349         c->max_tag = 0;
 350 error:
 351         return err;
 352 }
 353
 354 /**
 355  * p9_tag_cleanup - cleans up tags structure and reclaims resources
 356  * @c:  v9fs client struct
 357  *
 358  * This frees resources associated with the tags structure
 359  *
 360  */
 361 static void p9_tag_cleanup(struct p9_client *c)
 362 {
 363         int row, col;
 364
 365         /* check to insure all requests are idle */
 366         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 367                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 368                         if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
 369                                 p9_debug(P9_DEBUG_MUX,
 370                                          "Attempting to cleanup non-free tag %d,%d\n",
 371                                          row, col);
 372                                 /* TODO: delay execution of cleanup */
 373                                 return;
 374                         }
 375                 }
 376         }
 377
 378         if (c->tagpool) {
 379                 p9_idpool_put(0, c->tagpool); /* free reserved tag 0 */
 380                 p9_idpool_destroy(c->tagpool);
 381         }
 382
 383         /* free requests associated with tags */
 384         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 385                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 386                         kfree(c->reqs[row][col].wq);
 387                         kfree(c->reqs[row][col].tc);
 388                         kfree(c->reqs[row][col].rc);
 389                 }
 390                 kfree(c->reqs[row]);
 391         }
 392         c->max_tag = 0;
 393 }
 394
 395 /**
 396  * p9_free_req - free a request and clean-up as necessary
 397  * c: client state
 398  * r: request to release
 399  *
 400  */
 401
 402 static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
 403 {
 404         int tag = r->tc->tag;
 405         p9_debug(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
 406
 407         r->status = REQ_STATUS_IDLE;
 408         if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
 409                 p9_idpool_put(tag, c->tagpool);
 410 }
 411
 412 /**
 413  * p9_client_cb - call back from transport to client
 414  * c: client state
 415  * req: request received
 416  *
 417  */
 418 void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
 419 {
 420         p9_debug(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
 421         wake_up(req->wq);
 422         p9_debug(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
 423 }
 424 EXPORT_SYMBOL(p9_client_cb);
 425
 426 /**
 427  * p9_parse_header - parse header arguments out of a packet
 428  * @pdu: packet to parse
 429  * @size: size of packet
 430  * @type: type of request
 431  * @tag: tag of packet
 432  * @rewind: set if we need to rewind offset afterwards
 433  */
 434
 435 int
 436 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
 437                                                                 int rewind)
 438 {
 439         int8_t r_type;
 440         int16_t r_tag;
 441         int32_t r_size;
 442         int offset = pdu->offset;
 443         int err;
 444
 445         pdu->offset = 0;
 446         if (pdu->size == 0)
 447                 pdu->size = 7;
 448
 449         err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
 450         if (err)
 451                 goto rewind_and_exit;
 452
 453         pdu->size = r_size;
 454         pdu->id = r_type;
 455         pdu->tag = r_tag;
 456
 457         p9_debug(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n",
 458                  pdu->size, pdu->id, pdu->tag);
 459
 460         if (type)
 461                 *type = r_type;
 462         if (tag)
 463                 *tag = r_tag;
 464         if (size)
 465                 *size = r_size;
 466
 467
 468 rewind_and_exit:
 469         if (rewind)
 470                 pdu->offset = offset;
 471         return err;
 472 }
 473 EXPORT_SYMBOL(p9_parse_header);
 474
 475 /**
 476  * p9_check_errors - check 9p packet for error return and process it
 477  * @c: current client instance
 478  * @req: request to parse and check for error conditions
 479  *
 480  * returns error code if one is discovered, otherwise returns 0
 481  *
 482  * this will have to be more complicated if we have multiple
 483  * error packet types
 484  */
 485
 486 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 487 {
 488         int8_t type;
 489         int err;
 490         int ecode;
 491
 492         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 493         /*
 494          * dump the response from server
 495          * This should be after check errors which poplulate pdu_fcall.
 496          */
 497         trace_9p_protocol_dump(c, req->rc);
 498         if (err) {
 499                 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 500                 return err;
 501         }
 502         if (type != P9_RERROR && type != P9_RLERROR)
 503                 return 0;
 504
 505         if (!p9_is_proto_dotl(c)) {
 506                 char *ename;
 507                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 508                                   &ename, &ecode);
 509                 if (err)
 510                         goto out_err;
 511
 512                 if (p9_is_proto_dotu(c))
 513                         err = -ecode;
 514
 515                 if (!err || !IS_ERR_VALUE(err)) {
 516                         err = p9_errstr2errno(ename, strlen(ename));
 517
 518                         p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 519                                  -ecode, ename);
 520                 }
 521                 kfree(ename);
 522         } else {
 523                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 524                 err = -ecode;
 525
 526                 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 527         }
 528
 529         return err;
 530
 531 out_err:
 532         p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 533
 534         return err;
 535 }
 536
 537 /**
 538  * p9_check_zc_errors - check 9p packet for error return and process it
 539  * @c: current client instance
 540  * @req: request to parse and check for error conditions
 541  * @in_hdrlen: Size of response protocol buffer.
 542  *
 543  * returns error code if one is discovered, otherwise returns 0
 544  *
 545  * this will have to be more complicated if we have multiple
 546  * error packet types
 547  */
 548
 549 static int p9_check_zc_errors(struct p9_client *c, struct p9_req_t *req,
 550                               char *uidata, int in_hdrlen, int kern_buf)
 551 {
 552         int err;
 553         int ecode;
 554         int8_t type;
 555         char *ename = NULL;
 556
 557         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 558         /*
 559          * dump the response from server
 560          * This should be after parse_header which poplulate pdu_fcall.
 561          */
 562         trace_9p_protocol_dump(c, req->rc);
 563         if (err) {
 564                 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 565                 return err;
 566         }
 567
 568         if (type != P9_RERROR && type != P9_RLERROR)
 569                 return 0;
 570
 571         if (!p9_is_proto_dotl(c)) {
 572                 /* Error is reported in string format */
 573                 int len;
 574                 /* 7 = header size for RERROR; */
 575                 int inline_len = in_hdrlen - 7;
 576
 577                 len =  req->rc->size - req->rc->offset;
 578                 if (len > (P9_ZC_HDR_SZ - 7)) {
 579                         err = -EFAULT;
 580                         goto out_err;
 581                 }
 582
 583                 ename = &req->rc->sdata[req->rc->offset];
 584                 if (len > inline_len) {
 585                         /* We have error in external buffer */
 586                         if (kern_buf) {
 587                                 memcpy(ename + inline_len, uidata,
 588                                        len - inline_len);
 589                         } else {
 590                                 err = copy_from_user(ename + inline_len,
 591                                                      uidata, len - inline_len);
 592                                 if (err) {
 593                                         err = -EFAULT;
 594                                         goto out_err;
 595                                 }
 596                         }
 597                 }
 598                 ename = NULL;
 599                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 600                                   &ename, &ecode);
 601                 if (err)
 602                         goto out_err;
 603
 604                 if (p9_is_proto_dotu(c))
 605                         err = -ecode;
 606
 607                 if (!err || !IS_ERR_VALUE(err)) {
 608                         err = p9_errstr2errno(ename, strlen(ename));
 609
 610                         p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 611                                  -ecode, ename);
 612                 }
 613                 kfree(ename);
 614         } else {
 615                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 616                 err = -ecode;
 617
 618                 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 619         }
 620         return err;
 621
 622 out_err:
 623         p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 624         return err;
 625 }
 626
 627 static struct p9_req_t *
 628 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
 629
 630 /**
 631  * p9_client_flush - flush (cancel) a request
 632  * @c: client state
 633  * @oldreq: request to cancel
 634  *
 635  * This sents a flush for a particular request and links
 636  * the flush request to the original request.  The current
 637  * code only supports a single flush request although the protocol
 638  * allows for multiple flush requests to be sent for a single request.
 639  *
 640  */
 641
 642 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 643 {
 644         struct p9_req_t *req;
 645         int16_t oldtag;
 646         int err;
 647
 648         err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
 649         if (err)
 650                 return err;
 651
 652         p9_debug(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
 653
 654         req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
 655         if (IS_ERR(req))
 656                 return PTR_ERR(req);
 657
 658
 659         /*
 660          * if we haven't received a response for oldreq,
 661          * remove it from the list.
 662          */
 663         spin_lock(&c->lock);
 664         if (oldreq->status == REQ_STATUS_FLSH)
 665                 list_del(&oldreq->req_list);
 666         spin_unlock(&c->lock);
 667
 668         p9_free_req(c, req);
 669         return 0;
 670 }
 671
 672 static struct p9_req_t *p9_client_prepare_req(struct p9_client *c,
 673                                               int8_t type, int req_size,
 674                                               const char *fmt, va_list ap)
 675 {
 676         int tag, err;
 677         struct p9_req_t *req;
 678
 679         p9_debug(P9_DEBUG_MUX, "client %p op %d\n", c, type);
 680
 681         /* we allow for any status other than disconnected */
 682         if (c->status == Disconnected)
 683                 return ERR_PTR(-EIO);
 684
 685         /* if status is begin_disconnected we allow only clunk request */
 686         if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
 687                 return ERR_PTR(-EIO);
 688
 689         tag = P9_NOTAG;
 690         if (type != P9_TVERSION) {
 691                 tag = p9_idpool_get(c->tagpool);
 692                 if (tag < 0)
 693                         return ERR_PTR(-ENOMEM);
 694         }
 695
 696         req = p9_tag_alloc(c, tag, req_size);
 697         if (IS_ERR(req))
 698                 return req;
 699
 700         /* marshall the data */
 701         p9pdu_prepare(req->tc, tag, type);
 702         err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
 703         if (err)
 704                 goto reterr;
 705         p9pdu_finalize(c, req->tc);
 706         trace_9p_client_req(c, type, tag);
 707         return req;
 708 reterr:
 709         p9_free_req(c, req);
 710         return ERR_PTR(err);
 711 }
 712
 713 /**
 714  * p9_client_rpc - issue a request and wait for a response
 715  * @c: client session
 716  * @type: type of request
 717  * @fmt: protocol format string (see protocol.c)
 718  *
 719  * Returns request structure (which client must free using p9_free_req)
 720  */
 721
 722 static struct p9_req_t *
 723 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 724 {
 725         va_list ap;
 726         int sigpending, err;
 727         unsigned long flags;
 728         struct p9_req_t *req;
 729
 730         va_start(ap, fmt);
 731         req = p9_client_prepare_req(c, type, c->msize, fmt, ap);
 732         va_end(ap);
 733         if (IS_ERR(req))
 734                 return req;
 735
 736         if (signal_pending(current)) {
 737                 sigpending = 1;
 738                 clear_thread_flag(TIF_SIGPENDING);
 739         } else
 740                 sigpending = 0;
 741
 742         err = c->trans_mod->request(c, req);
 743         if (err < 0) {
 744                 if (err != -ERESTARTSYS && err != -EFAULT)
 745                         c->status = Disconnected;
 746                 goto reterr;
 747         }
 748 again:
 749         /* Wait for the response */
 750         err = wait_event_interruptible(*req->wq,
 751                                        req->status >= REQ_STATUS_RCVD);
 752
 753         if ((err == -ERESTARTSYS) && (c->status == Connected)
 754                                   && (type == P9_TFLUSH)) {
 755                 sigpending = 1;
 756                 clear_thread_flag(TIF_SIGPENDING);
 757                 goto again;
 758         }
 759
 760         if (req->status == REQ_STATUS_ERROR) {
 761                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 762                 err = req->t_err;
 763         }
 764         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 765                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 766                 sigpending = 1;
 767                 clear_thread_flag(TIF_SIGPENDING);
 768
 769                 if (c->trans_mod->cancel(c, req))
 770                         p9_client_flush(c, req);
 771
 772                 /* if we received the response anyway, don't signal error */
 773                 if (req->status == REQ_STATUS_RCVD)
 774                         err = 0;
 775         }
 776         if (sigpending) {
 777                 spin_lock_irqsave(&current->sighand->siglock, flags);
 778                 recalc_sigpending();
 779                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 780         }
 781         if (err < 0)
 782                 goto reterr;
 783
 784         err = p9_check_errors(c, req);
 785         trace_9p_client_res(c, type, req->rc->tag, err);
 786         if (!err)
 787                 return req;
 788 reterr:
 789         p9_free_req(c, req);
 790         return ERR_PTR(safe_errno(err));
 791 }
 792
 793 /**
 794  * p9_client_zc_rpc - issue a request and wait for a response
 795  * @c: client session
 796  * @type: type of request
 797  * @uidata: user bffer that should be ued for zero copy read
 798  * @uodata: user buffer that shoud be user for zero copy write
 799  * @inlen: read buffer size
 800  * @olen: write buffer size
 801  * @hdrlen: reader header size, This is the size of response protocol data
 802  * @fmt: protocol format string (see protocol.c)
 803  *
 804  * Returns request structure (which client must free using p9_free_req)
 805  */
 806 static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
 807                                          char *uidata, char *uodata,
 808                                          int inlen, int olen, int in_hdrlen,
 809                                          int kern_buf, const char *fmt, ...)
 810 {
 811         va_list ap;
 812         int sigpending, err;
 813         unsigned long flags;
 814         struct p9_req_t *req;
 815
 816         va_start(ap, fmt);
 817         /*
 818          * We allocate a inline protocol data of only 4k bytes.
 819          * The actual content is passed in zero-copy fashion.
 820          */
 821         req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, fmt, ap);
 822         va_end(ap);
 823         if (IS_ERR(req))
 824                 return req;
 825
 826         if (signal_pending(current)) {
 827                 sigpending = 1;
 828                 clear_thread_flag(TIF_SIGPENDING);
 829         } else
 830                 sigpending = 0;
 831
 832         /* If we are called with KERNEL_DS force kern_buf */
 833         if (segment_eq(get_fs(), KERNEL_DS))
 834                 kern_buf = 1;
 835
 836         err = c->trans_mod->zc_request(c, req, uidata, uodata,
 837                                        inlen, olen, in_hdrlen, kern_buf);
 838         if (err < 0) {
 839                 if (err == -EIO)
 840                         c->status = Disconnected;
 841                 goto reterr;
 842         }
 843         if (req->status == REQ_STATUS_ERROR) {
 844                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 845                 err = req->t_err;
 846         }
 847         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 848                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 849                 sigpending = 1;
 850                 clear_thread_flag(TIF_SIGPENDING);
 851
 852                 if (c->trans_mod->cancel(c, req))
 853                         p9_client_flush(c, req);
 854
 855                 /* if we received the response anyway, don't signal error */
 856                 if (req->status == REQ_STATUS_RCVD)
 857                         err = 0;
 858         }
 859         if (sigpending) {
 860                 spin_lock_irqsave(&current->sighand->siglock, flags);
 861                 recalc_sigpending();
 862                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 863         }
 864         if (err < 0)
 865                 goto reterr;
 866
 867         err = p9_check_zc_errors(c, req, uidata, in_hdrlen, kern_buf);
 868         trace_9p_client_res(c, type, req->rc->tag, err);
 869         if (!err)
 870                 return req;
 871 reterr:
 872         p9_free_req(c, req);
 873         return ERR_PTR(safe_errno(err));
 874 }
 875
 876 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 877 {
 878         int ret;
 879         struct p9_fid *fid;
 880         unsigned long flags;
 881
 882         p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt);
 883         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
 884         if (!fid)
 885                 return ERR_PTR(-ENOMEM);
 886
 887         ret = p9_idpool_get(clnt->fidpool);
 888         if (ret < 0) {
 889                 ret = -ENOSPC;
 890                 goto error;
 891         }
 892         fid->fid = ret;
 893
 894         memset(&fid->qid, 0, sizeof(struct p9_qid));
 895         fid->mode = -1;
 896         fid->uid = current_fsuid();
 897         fid->clnt = clnt;
 898         fid->rdir = NULL;
 899         spin_lock_irqsave(&clnt->lock, flags);
 900         list_add(&fid->flist, &clnt->fidlist);
 901         spin_unlock_irqrestore(&clnt->lock, flags);
 902
 903         return fid;
 904
 905 error:
 906         kfree(fid);
 907         return ERR_PTR(ret);
 908 }
 909
 910 static void p9_fid_destroy(struct p9_fid *fid)
 911 {
 912         struct p9_client *clnt;
 913         unsigned long flags;
 914
 915         p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
 916         clnt = fid->clnt;
 917         p9_idpool_put(fid->fid, clnt->fidpool);
 918         spin_lock_irqsave(&clnt->lock, flags);
 919         list_del(&fid->flist);
 920         spin_unlock_irqrestore(&clnt->lock, flags);
 921         kfree(fid->rdir);
 922         kfree(fid);
 923 }
 924
 925 static int p9_client_version(struct p9_client *c)
 926 {
 927         int err = 0;
 928         struct p9_req_t *req;
 929         char *version;
 930         int msize;
 931
 932         p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
 933                  c->msize, c->proto_version);
 934
 935         switch (c->proto_version) {
 936         case p9_proto_2000L:
 937                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 938                                         c->msize, "9P2000.L");
 939                 break;
 940         case p9_proto_2000u:
 941                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 942                                         c->msize, "9P2000.u");
 943                 break;
 944         case p9_proto_legacy:
 945                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 946                                         c->msize, "9P2000");
 947                 break;
 948         default:
 949                 return -EINVAL;
 950                 break;
 951         }
 952
 953         if (IS_ERR(req))
 954                 return PTR_ERR(req);
 955
 956         err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
 957         if (err) {
 958                 p9_debug(P9_DEBUG_9P, "version error %d\n", err);
 959                 trace_9p_protocol_dump(c, req->rc);
 960                 goto error;
 961         }
 962
 963         p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
 964         if (!strncmp(version, "9P2000.L", 8))
 965                 c->proto_version = p9_proto_2000L;
 966         else if (!strncmp(version, "9P2000.u", 8))
 967                 c->proto_version = p9_proto_2000u;
 968         else if (!strncmp(version, "9P2000", 6))
 969                 c->proto_version = p9_proto_legacy;
 970         else {
 971                 err = -EREMOTEIO;
 972                 goto error;
 973         }
 974
 975         if (msize < c->msize)
 976                 c->msize = msize;
 977
 978 error:
 979         kfree(version);
 980         p9_free_req(c, req);
 981
 982         return err;
 983 }
 984
 985 struct p9_client *p9_client_create(const char *dev_name, char *options)
 986 {
 987         int err;
 988         struct p9_client *clnt;
 989
 990         err = 0;
 991         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
 992         if (!clnt)
 993                 return ERR_PTR(-ENOMEM);
 994
 995         clnt->trans_mod = NULL;
 996         clnt->trans = NULL;
 997         spin_lock_init(&clnt->lock);
 998         INIT_LIST_HEAD(&clnt->fidlist);
 999
1000         err = p9_tag_init(clnt);
1001         if (err < 0)
1002                 goto free_client;
1003
1004         err = parse_opts(options, clnt);
1005         if (err < 0)
1006                 goto destroy_tagpool;
1007
1008         if (!clnt->trans_mod)
1009                 clnt->trans_mod = v9fs_get_trans_by_name("virtio");
1010
1011         if (!clnt->trans_mod)
1012                 clnt->trans_mod = v9fs_get_default_trans();
1013
1014         if (clnt->trans_mod == NULL) {
1015                 err = -EPROTONOSUPPORT;
1016                 p9_debug(P9_DEBUG_ERROR,
1017                          "No transport defined or default transport\n");
1018                 goto destroy_tagpool;
1019         }
1020
1021         clnt->fidpool = p9_idpool_create();
1022         if (IS_ERR(clnt->fidpool)) {
1023                 err = PTR_ERR(clnt->fidpool);
1024                 goto put_trans;
1025         }
1026
1027         p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1028                  clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1029
1030         err = clnt->trans_mod->create(clnt, dev_name, options);
1031         if (err)
1032                 goto destroy_fidpool;
1033
1034         if (clnt->msize > clnt->trans_mod->maxsize)
1035                 clnt->msize = clnt->trans_mod->maxsize;
1036
1037         err = p9_client_version(clnt);
1038         if (err)
1039                 goto close_trans;
1040
1041         return clnt;
1042
1043 close_trans:
1044         clnt->trans_mod->close(clnt);
1045 destroy_fidpool:
1046         p9_idpool_destroy(clnt->fidpool);
1047 put_trans:
1048         v9fs_put_trans(clnt->trans_mod);
1049 destroy_tagpool:
1050         p9_idpool_destroy(clnt->tagpool);
1051 free_client:
1052         kfree(clnt);
1053         return ERR_PTR(err);
1054 }
1055 EXPORT_SYMBOL(p9_client_create);
1056
1057 void p9_client_destroy(struct p9_client *clnt)
1058 {
1059         struct p9_fid *fid, *fidptr;
1060
1061         p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
1062
1063         if (clnt->trans_mod)
1064                 clnt->trans_mod->close(clnt);
1065
1066         v9fs_put_trans(clnt->trans_mod);
1067
1068         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
1069                 pr_info("Found fid %d not clunked\n", fid->fid);
1070                 p9_fid_destroy(fid);
1071         }
1072
1073         if (clnt->fidpool)
1074                 p9_idpool_destroy(clnt->fidpool);
1075
1076         p9_tag_cleanup(clnt);
1077
1078         kfree(clnt);
1079 }
1080 EXPORT_SYMBOL(p9_client_destroy);
1081
1082 void p9_client_disconnect(struct p9_client *clnt)
1083 {
1084         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1085         clnt->status = Disconnected;
1086 }
1087 EXPORT_SYMBOL(p9_client_disconnect);
1088
1089 void p9_client_begin_disconnect(struct p9_client *clnt)
1090 {
1091         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1092         clnt->status = BeginDisconnect;
1093 }
1094 EXPORT_SYMBOL(p9_client_begin_disconnect);
1095
1096 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1097         char *uname, kuid_t n_uname, char *aname)
1098 {
1099         int err = 0;
1100         struct p9_req_t *req;
1101         struct p9_fid *fid;
1102         struct p9_qid qid;
1103
1104
1105         p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1106                  afid ? afid->fid : -1, uname, aname);
1107         fid = p9_fid_create(clnt);
1108         if (IS_ERR(fid)) {
1109                 err = PTR_ERR(fid);
1110                 fid = NULL;
1111                 goto error;
1112         }
1113
1114         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?u", fid->fid,
1115                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1116         if (IS_ERR(req)) {
1117                 err = PTR_ERR(req);
1118                 goto error;
1119         }
1120
1121         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
1122         if (err) {
1123                 trace_9p_protocol_dump(clnt, req->rc);
1124                 p9_free_req(clnt, req);
1125                 goto error;
1126         }
1127
1128         p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1129                  qid.type, (unsigned long long)qid.path, qid.version);
1130
1131         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1132
1133         p9_free_req(clnt, req);
1134         return fid;
1135
1136 error:
1137         if (fid)
1138                 p9_fid_destroy(fid);
1139         return ERR_PTR(err);
1140 }
1141 EXPORT_SYMBOL(p9_client_attach);
1142
1143 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1144                 char **wnames, int clone)
1145 {
1146         int err;
1147         struct p9_client *clnt;
1148         struct p9_fid *fid;
1149         struct p9_qid *wqids;
1150         struct p9_req_t *req;
1151         uint16_t nwqids, count;
1152
1153         err = 0;
1154         wqids = NULL;
1155         clnt = oldfid->clnt;
1156         if (clone) {
1157                 fid = p9_fid_create(clnt);
1158                 if (IS_ERR(fid)) {
1159                         err = PTR_ERR(fid);
1160                         fid = NULL;
1161                         goto error;
1162                 }
1163
1164                 fid->uid = oldfid->uid;
1165         } else
1166                 fid = oldfid;
1167
1168
1169         p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1170                  oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1171
1172         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1173                                                                 nwname, wnames);
1174         if (IS_ERR(req)) {
1175                 err = PTR_ERR(req);
1176                 goto error;
1177         }
1178
1179         err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1180         if (err) {
1181                 trace_9p_protocol_dump(clnt, req->rc);
1182                 p9_free_req(clnt, req);
1183                 goto clunk_fid;
1184         }
1185         p9_free_req(clnt, req);
1186
1187         p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1188
1189         if (nwqids != nwname) {
1190                 err = -ENOENT;
1191                 goto clunk_fid;
1192         }
1193
1194         for (count = 0; count < nwqids; count++)
1195                 p9_debug(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
1196                         count, wqids[count].type,
1197                         (unsigned long long)wqids[count].path,
1198                         wqids[count].version);
1199
1200         if (nwname)
1201                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1202         else
1203                 fid->qid = oldfid->qid;
1204
1205         kfree(wqids);
1206         return fid;
1207
1208 clunk_fid:
1209         kfree(wqids);
1210         p9_client_clunk(fid);
1211         fid = NULL;
1212
1213 error:
1214         if (fid && (fid != oldfid))
1215                 p9_fid_destroy(fid);
1216
1217         return ERR_PTR(err);
1218 }
1219 EXPORT_SYMBOL(p9_client_walk);
1220
1221 int p9_client_open(struct p9_fid *fid, int mode)
1222 {
1223         int err;
1224         struct p9_client *clnt;
1225         struct p9_req_t *req;
1226         struct p9_qid qid;
1227         int iounit;
1228
1229         clnt = fid->clnt;
1230         p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1231                 p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1232         err = 0;
1233
1234         if (fid->mode != -1)
1235                 return -EINVAL;
1236
1237         if (p9_is_proto_dotl(clnt))
1238                 req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1239         else
1240                 req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1241         if (IS_ERR(req)) {
1242                 err = PTR_ERR(req);
1243                 goto error;
1244         }
1245
1246         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1247         if (err) {
1248                 trace_9p_protocol_dump(clnt, req->rc);
1249                 goto free_and_error;
1250         }
1251
1252         p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1253                 p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1254                 (unsigned long long)qid.path, qid.version, iounit);
1255
1256         fid->mode = mode;
1257         fid->iounit = iounit;
1258
1259 free_and_error:
1260         p9_free_req(clnt, req);
1261 error:
1262         return err;
1263 }
1264 EXPORT_SYMBOL(p9_client_open);
1265
1266 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
1267                 kgid_t gid, struct p9_qid *qid)
1268 {
1269         int err = 0;
1270         struct p9_client *clnt;
1271         struct p9_req_t *req;
1272         int iounit;
1273
1274         p9_debug(P9_DEBUG_9P,
1275                         ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1276                         ofid->fid, name, flags, mode,
1277                         from_kgid(&init_user_ns, gid));
1278         clnt = ofid->clnt;
1279
1280         if (ofid->mode != -1)
1281                 return -EINVAL;
1282
1283         req = p9_client_rpc(clnt, P9_TLCREATE, "dsddg", ofid->fid, name, flags,
1284                         mode, gid);
1285         if (IS_ERR(req)) {
1286                 err = PTR_ERR(req);
1287                 goto error;
1288         }
1289
1290         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1291         if (err) {
1292                 trace_9p_protocol_dump(clnt, req->rc);
1293                 goto free_and_error;
1294         }
1295
1296         p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1297                         qid->type,
1298                         (unsigned long long)qid->path,
1299                         qid->version, iounit);
1300
1301         ofid->mode = mode;
1302         ofid->iounit = iounit;
1303
1304 free_and_error:
1305         p9_free_req(clnt, req);
1306 error:
1307         return err;
1308 }
1309 EXPORT_SYMBOL(p9_client_create_dotl);
1310
1311 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1312                      char *extension)
1313 {
1314         int err;
1315         struct p9_client *clnt;
1316         struct p9_req_t *req;
1317         struct p9_qid qid;
1318         int iounit;
1319
1320         p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1321                                                 fid->fid, name, perm, mode);
1322         err = 0;
1323         clnt = fid->clnt;
1324
1325         if (fid->mode != -1)
1326                 return -EINVAL;
1327
1328         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1329                                 mode, extension);
1330         if (IS_ERR(req)) {
1331                 err = PTR_ERR(req);
1332                 goto error;
1333         }
1334
1335         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1336         if (err) {
1337                 trace_9p_protocol_dump(clnt, req->rc);
1338                 goto free_and_error;
1339         }
1340
1341         p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1342                                 qid.type,
1343                                 (unsigned long long)qid.path,
1344                                 qid.version, iounit);
1345
1346         fid->mode = mode;
1347         fid->iounit = iounit;
1348
1349 free_and_error:
1350         p9_free_req(clnt, req);
1351 error:
1352         return err;
1353 }
1354 EXPORT_SYMBOL(p9_client_fcreate);
1355
1356 int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, kgid_t gid,
1357                 struct p9_qid *qid)
1358 {
1359         int err = 0;
1360         struct p9_client *clnt;
1361         struct p9_req_t *req;
1362
1363         p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1364                         dfid->fid, name, symtgt);
1365         clnt = dfid->clnt;
1366
1367         req = p9_client_rpc(clnt, P9_TSYMLINK, "dssg", dfid->fid, name, symtgt,
1368                         gid);
1369         if (IS_ERR(req)) {
1370                 err = PTR_ERR(req);
1371                 goto error;
1372         }
1373
1374         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1375         if (err) {
1376                 trace_9p_protocol_dump(clnt, req->rc);
1377                 goto free_and_error;
1378         }
1379
1380         p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1381                         qid->type, (unsigned long long)qid->path, qid->version);
1382
1383 free_and_error:
1384         p9_free_req(clnt, req);
1385 error:
1386         return err;
1387 }
1388 EXPORT_SYMBOL(p9_client_symlink);
1389
1390 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
1391 {
1392         struct p9_client *clnt;
1393         struct p9_req_t *req;
1394
1395         p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1396                         dfid->fid, oldfid->fid, newname);
1397         clnt = dfid->clnt;
1398         req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1399                         newname);
1400         if (IS_ERR(req))
1401                 return PTR_ERR(req);
1402
1403         p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
1404         p9_free_req(clnt, req);
1405         return 0;
1406 }
1407 EXPORT_SYMBOL(p9_client_link);
1408
1409 int p9_client_fsync(struct p9_fid *fid, int datasync)
1410 {
1411         int err;
1412         struct p9_client *clnt;
1413         struct p9_req_t *req;
1414
1415         p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1416                         fid->fid, datasync);
1417         err = 0;
1418         clnt = fid->clnt;
1419
1420         req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1421         if (IS_ERR(req)) {
1422                 err = PTR_ERR(req);
1423                 goto error;
1424         }
1425
1426         p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1427
1428         p9_free_req(clnt, req);
1429
1430 error:
1431         return err;
1432 }
1433 EXPORT_SYMBOL(p9_client_fsync);
1434
1435 int p9_client_clunk(struct p9_fid *fid)
1436 {
1437         int err;
1438         struct p9_client *clnt;
1439         struct p9_req_t *req;
1440         int retries = 0;
1441
1442         if (!fid) {
1443                 pr_warn("%s (%d): Trying to clunk with NULL fid\n",
1444                         __func__, task_pid_nr(current));
1445                 dump_stack();
1446                 return 0;
1447         }
1448
1449 again:
1450         p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n", fid->fid,
1451                                                                 retries);
1452         err = 0;
1453         clnt = fid->clnt;
1454
1455         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1456         if (IS_ERR(req)) {
1457                 err = PTR_ERR(req);
1458                 goto error;
1459         }
1460
1461         p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1462
1463         p9_free_req(clnt, req);
1464 error:
1465         /*
1466          * Fid is not valid even after a failed clunk
1467          * If interrupted, retry once then give up and
1468          * leak fid until umount.
1469          */
1470         if (err == -ERESTARTSYS) {
1471                 if (retries++ == 0)
1472                         goto again;
1473         } else
1474                 p9_fid_destroy(fid);
1475         return err;
1476 }
1477 EXPORT_SYMBOL(p9_client_clunk);
1478
1479 int p9_client_remove(struct p9_fid *fid)
1480 {
1481         int err;
1482         struct p9_client *clnt;
1483         struct p9_req_t *req;
1484
1485         p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1486         err = 0;
1487         clnt = fid->clnt;
1488
1489         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1490         if (IS_ERR(req)) {
1491                 err = PTR_ERR(req);
1492                 goto error;
1493         }
1494
1495         p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1496
1497         p9_free_req(clnt, req);
1498 error:
1499         if (err == -ERESTARTSYS)
1500                 p9_client_clunk(fid);
1501         else
1502                 p9_fid_destroy(fid);
1503         return err;
1504 }
1505 EXPORT_SYMBOL(p9_client_remove);
1506
1507 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1508 {
1509         int err = 0;
1510         struct p9_req_t *req;
1511         struct p9_client *clnt;
1512
1513         p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1514                    dfid->fid, name, flags);
1515
1516         clnt = dfid->clnt;
1517         req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1518         if (IS_ERR(req)) {
1519                 err = PTR_ERR(req);
1520                 goto error;
1521         }
1522         p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1523
1524         p9_free_req(clnt, req);
1525 error:
1526         return err;
1527 }
1528 EXPORT_SYMBOL(p9_client_unlinkat);
1529
1530 int
1531 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1532                                                                 u32 count)
1533 {
1534         char *dataptr;
1535         int kernel_buf = 0;
1536         struct p9_req_t *req;
1537         struct p9_client *clnt;
1538         int err, rsize, non_zc = 0;
1539
1540
1541         p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
1542                    fid->fid, (unsigned long long) offset, count);
1543         err = 0;
1544         clnt = fid->clnt;
1545
1546         rsize = fid->iounit;
1547         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1548                 rsize = clnt->msize - P9_IOHDRSZ;
1549
1550         if (count < rsize)
1551                 rsize = count;
1552
1553         /* Don't bother zerocopy for small IO (< 1024) */
1554         if (clnt->trans_mod->zc_request && rsize > 1024) {
1555                 char *indata;
1556                 if (data) {
1557                         kernel_buf = 1;
1558                         indata = data;
1559                 } else
1560                         indata = (__force char *)udata;
1561                 /*
1562                  * response header len is 11
1563                  * PDU Header(7) + IO Size (4)
1564                  */
1565                 req = p9_client_zc_rpc(clnt, P9_TREAD, indata, NULL, rsize, 0,
1566                                        11, kernel_buf, "dqd", fid->fid,
1567                                        offset, rsize);
1568         } else {
1569                 non_zc = 1;
1570                 req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1571                                     rsize);
1572         }
1573         if (IS_ERR(req)) {
1574                 err = PTR_ERR(req);
1575                 goto error;
1576         }
1577
1578         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1579         if (err) {
1580                 trace_9p_protocol_dump(clnt, req->rc);
1581                 goto free_and_error;
1582         }
1583
1584         p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1585
1586         if (non_zc) {
1587                 if (data) {
1588                         memmove(data, dataptr, count);
1589                 } else {
1590                         err = copy_to_user(udata, dataptr, count);
1591                         if (err) {
1592                                 err = -EFAULT;
1593                                 goto free_and_error;
1594                         }
1595                 }
1596         }
1597         p9_free_req(clnt, req);
1598         return count;
1599
1600 free_and_error:
1601         p9_free_req(clnt, req);
1602 error:
1603         return err;
1604 }
1605 EXPORT_SYMBOL(p9_client_read);
1606
1607 int
1608 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1609                                                         u64 offset, u32 count)
1610 {
1611         int err, rsize;
1612         int kernel_buf = 0;
1613         struct p9_client *clnt;
1614         struct p9_req_t *req;
1615
1616         p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1617                                 fid->fid, (unsigned long long) offset, count);
1618         err = 0;
1619         clnt = fid->clnt;
1620
1621         rsize = fid->iounit;
1622         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1623                 rsize = clnt->msize - P9_IOHDRSZ;
1624
1625         if (count < rsize)
1626                 rsize = count;
1627
1628         /* Don't bother zerocopy for small IO (< 1024) */
1629         if (clnt->trans_mod->zc_request && rsize > 1024) {
1630                 char *odata;
1631                 if (data) {
1632                         kernel_buf = 1;
1633                         odata = data;
1634                 } else
1635                         odata = (char *)udata;
1636                 req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, odata, 0, rsize,
1637                                        P9_ZC_HDR_SZ, kernel_buf, "dqd",
1638                                        fid->fid, offset, rsize);
1639         } else {
1640                 if (data)
1641                         req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid,
1642                                             offset, rsize, data);
1643                 else
1644                         req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid,
1645                                             offset, rsize, udata);
1646         }
1647         if (IS_ERR(req)) {
1648                 err = PTR_ERR(req);
1649                 goto error;
1650         }
1651
1652         err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1653         if (err) {
1654                 trace_9p_protocol_dump(clnt, req->rc);
1655                 goto free_and_error;
1656         }
1657
1658         p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1659
1660         p9_free_req(clnt, req);
1661         return count;
1662
1663 free_and_error:
1664         p9_free_req(clnt, req);
1665 error:
1666         return err;
1667 }
1668 EXPORT_SYMBOL(p9_client_write);
1669
1670 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1671 {
1672         int err;
1673         struct p9_client *clnt;
1674         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1675         struct p9_req_t *req;
1676         u16 ignored;
1677
1678         p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1679
1680         if (!ret)
1681                 return ERR_PTR(-ENOMEM);
1682
1683         err = 0;
1684         clnt = fid->clnt;
1685
1686         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1687         if (IS_ERR(req)) {
1688                 err = PTR_ERR(req);
1689                 goto error;
1690         }
1691
1692         err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1693         if (err) {
1694                 trace_9p_protocol_dump(clnt, req->rc);
1695                 p9_free_req(clnt, req);
1696                 goto error;
1697         }
1698
1699         p9_debug(P9_DEBUG_9P,
1700                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1701                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1702                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1703                 "<<<    uid=%d gid=%d n_muid=%d\n",
1704                 ret->size, ret->type, ret->dev, ret->qid.type,
1705                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1706                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1707                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1708                 from_kuid(&init_user_ns, ret->n_uid),
1709                 from_kgid(&init_user_ns, ret->n_gid),
1710                 from_kuid(&init_user_ns, ret->n_muid));
1711
1712         p9_free_req(clnt, req);
1713         return ret;
1714
1715 error:
1716         kfree(ret);
1717         return ERR_PTR(err);
1718 }
1719 EXPORT_SYMBOL(p9_client_stat);
1720
1721 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1722                                                         u64 request_mask)
1723 {
1724         int err;
1725         struct p9_client *clnt;
1726         struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1727                                                                 GFP_KERNEL);
1728         struct p9_req_t *req;
1729
1730         p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1731                                                         fid->fid, request_mask);
1732
1733         if (!ret)
1734                 return ERR_PTR(-ENOMEM);
1735
1736         err = 0;
1737         clnt = fid->clnt;
1738
1739         req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1740         if (IS_ERR(req)) {
1741                 err = PTR_ERR(req);
1742                 goto error;
1743         }
1744
1745         err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1746         if (err) {
1747                 trace_9p_protocol_dump(clnt, req->rc);
1748                 p9_free_req(clnt, req);
1749                 goto error;
1750         }
1751
1752         p9_debug(P9_DEBUG_9P,
1753                 "<<< RGETATTR st_result_mask=%lld\n"
1754                 "<<< qid=%x.%llx.%x\n"
1755                 "<<< st_mode=%8.8x st_nlink=%llu\n"
1756                 "<<< st_uid=%d st_gid=%d\n"
1757                 "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1758                 "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1759                 "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1760                 "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1761                 "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1762                 "<<< st_gen=%lld st_data_version=%lld",
1763                 ret->st_result_mask, ret->qid.type, ret->qid.path,
1764                 ret->qid.version, ret->st_mode, ret->st_nlink,
1765                 from_kuid(&init_user_ns, ret->st_uid),
1766                 from_kgid(&init_user_ns, ret->st_gid),
1767                 ret->st_rdev, ret->st_size, ret->st_blksize,
1768                 ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1769                 ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1770                 ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1771                 ret->st_gen, ret->st_data_version);
1772
1773         p9_free_req(clnt, req);
1774         return ret;
1775
1776 error:
1777         kfree(ret);
1778         return ERR_PTR(err);
1779 }
1780 EXPORT_SYMBOL(p9_client_getattr_dotl);
1781
1782 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1783 {
1784         int ret;
1785
1786         /* NOTE: size shouldn't include its own length */
1787         /* size[2] type[2] dev[4] qid[13] */
1788         /* mode[4] atime[4] mtime[4] length[8]*/
1789         /* name[s] uid[s] gid[s] muid[s] */
1790         ret = 2+4+13+4+4+4+8+2+2+2+2;
1791
1792         if (wst->name)
1793                 ret += strlen(wst->name);
1794         if (wst->uid)
1795                 ret += strlen(wst->uid);
1796         if (wst->gid)
1797                 ret += strlen(wst->gid);
1798         if (wst->muid)
1799                 ret += strlen(wst->muid);
1800
1801         if ((proto_version == p9_proto_2000u) ||
1802                 (proto_version == p9_proto_2000L)) {
1803                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1804                 if (wst->extension)
1805                         ret += strlen(wst->extension);
1806         }
1807
1808         return ret;
1809 }
1810
1811 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1812 {
1813         int err;
1814         struct p9_req_t *req;
1815         struct p9_client *clnt;
1816
1817         err = 0;
1818         clnt = fid->clnt;
1819         wst->size = p9_client_statsize(wst, clnt->proto_version);
1820         p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1821         p9_debug(P9_DEBUG_9P,
1822                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1823                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1824                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1825                 "     uid=%d gid=%d n_muid=%d\n",
1826                 wst->size, wst->type, wst->dev, wst->qid.type,
1827                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1828                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1829                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1830                 from_kuid(&init_user_ns, wst->n_uid),
1831                 from_kgid(&init_user_ns, wst->n_gid),
1832                 from_kuid(&init_user_ns, wst->n_muid));
1833
1834         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1835         if (IS_ERR(req)) {
1836                 err = PTR_ERR(req);
1837                 goto error;
1838         }
1839
1840         p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1841
1842         p9_free_req(clnt, req);
1843 error:
1844         return err;
1845 }
1846 EXPORT_SYMBOL(p9_client_wstat);
1847
1848 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1849 {
1850         int err;
1851         struct p9_req_t *req;
1852         struct p9_client *clnt;
1853
1854         err = 0;
1855         clnt = fid->clnt;
1856         p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1857         p9_debug(P9_DEBUG_9P,
1858                 "    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1859                 "    atime_sec=%lld atime_nsec=%lld\n"
1860                 "    mtime_sec=%lld mtime_nsec=%lld\n",
1861                 p9attr->valid, p9attr->mode,
1862                 from_kuid(&init_user_ns, p9attr->uid),
1863                 from_kgid(&init_user_ns, p9attr->gid),
1864                 p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1865                 p9attr->mtime_sec, p9attr->mtime_nsec);
1866
1867         req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1868
1869         if (IS_ERR(req)) {
1870                 err = PTR_ERR(req);
1871                 goto error;
1872         }
1873         p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1874         p9_free_req(clnt, req);
1875 error:
1876         return err;
1877 }
1878 EXPORT_SYMBOL(p9_client_setattr);
1879
1880 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1881 {
1882         int err;
1883         struct p9_req_t *req;
1884         struct p9_client *clnt;
1885
1886         err = 0;
1887         clnt = fid->clnt;
1888
1889         p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1890
1891         req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1892         if (IS_ERR(req)) {
1893                 err = PTR_ERR(req);
1894                 goto error;
1895         }
1896
1897         err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1898                 &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1899                 &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1900         if (err) {
1901                 trace_9p_protocol_dump(clnt, req->rc);
1902                 p9_free_req(clnt, req);
1903                 goto error;
1904         }
1905
1906         p9_debug(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1907                 "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1908                 "fsid %llu namelen %ld\n",
1909                 fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1910                 sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1911                 sb->fsid, (long int)sb->namelen);
1912
1913         p9_free_req(clnt, req);
1914 error:
1915         return err;
1916 }
1917 EXPORT_SYMBOL(p9_client_statfs);
1918
1919 int p9_client_rename(struct p9_fid *fid,
1920                      struct p9_fid *newdirfid, const char *name)
1921 {
1922         int err;
1923         struct p9_req_t *req;
1924         struct p9_client *clnt;
1925
1926         err = 0;
1927         clnt = fid->clnt;
1928
1929         p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1930                         fid->fid, newdirfid->fid, name);
1931
1932         req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1933                         newdirfid->fid, name);
1934         if (IS_ERR(req)) {
1935                 err = PTR_ERR(req);
1936                 goto error;
1937         }
1938
1939         p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1940
1941         p9_free_req(clnt, req);
1942 error:
1943         return err;
1944 }
1945 EXPORT_SYMBOL(p9_client_rename);
1946
1947 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1948                        struct p9_fid *newdirfid, const char *new_name)
1949 {
1950         int err;
1951         struct p9_req_t *req;
1952         struct p9_client *clnt;
1953
1954         err = 0;
1955         clnt = olddirfid->clnt;
1956
1957         p9_debug(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1958                    " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1959                    newdirfid->fid, new_name);
1960
1961         req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1962                             old_name, newdirfid->fid, new_name);
1963         if (IS_ERR(req)) {
1964                 err = PTR_ERR(req);
1965                 goto error;
1966         }
1967
1968         p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
1969                    newdirfid->fid, new_name);
1970
1971         p9_free_req(clnt, req);
1972 error:
1973         return err;
1974 }
1975 EXPORT_SYMBOL(p9_client_renameat);
1976
1977 /*
1978  * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1979  */
1980 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1981                                 const char *attr_name, u64 *attr_size)
1982 {
1983         int err;
1984         struct p9_req_t *req;
1985         struct p9_client *clnt;
1986         struct p9_fid *attr_fid;
1987
1988         err = 0;
1989         clnt = file_fid->clnt;
1990         attr_fid = p9_fid_create(clnt);
1991         if (IS_ERR(attr_fid)) {
1992                 err = PTR_ERR(attr_fid);
1993                 attr_fid = NULL;
1994                 goto error;
1995         }
1996         p9_debug(P9_DEBUG_9P,
1997                 ">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
1998                 file_fid->fid, attr_fid->fid, attr_name);
1999
2000         req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
2001                         file_fid->fid, attr_fid->fid, attr_name);
2002         if (IS_ERR(req)) {
2003                 err = PTR_ERR(req);
2004                 goto error;
2005         }
2006         err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
2007         if (err) {
2008                 trace_9p_protocol_dump(clnt, req->rc);
2009                 p9_free_req(clnt, req);
2010                 goto clunk_fid;
2011         }
2012         p9_free_req(clnt, req);
2013         p9_debug(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
2014                 attr_fid->fid, *attr_size);
2015         return attr_fid;
2016 clunk_fid:
2017         p9_client_clunk(attr_fid);
2018         attr_fid = NULL;
2019 error:
2020         if (attr_fid && (attr_fid != file_fid))
2021                 p9_fid_destroy(attr_fid);
2022
2023         return ERR_PTR(err);
2024 }
2025 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
2026
2027 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
2028                         u64 attr_size, int flags)
2029 {
2030         int err;
2031         struct p9_req_t *req;
2032         struct p9_client *clnt;
2033
2034         p9_debug(P9_DEBUG_9P,
2035                 ">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
2036                 fid->fid, name, (long long)attr_size, flags);
2037         err = 0;
2038         clnt = fid->clnt;
2039         req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2040                         fid->fid, name, attr_size, flags);
2041         if (IS_ERR(req)) {
2042                 err = PTR_ERR(req);
2043                 goto error;
2044         }
2045         p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2046         p9_free_req(clnt, req);
2047 error:
2048         return err;
2049 }
2050 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2051
2052 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2053 {
2054         int err, rsize, non_zc = 0;
2055         struct p9_client *clnt;
2056         struct p9_req_t *req;
2057         char *dataptr;
2058
2059         p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2060                                 fid->fid, (unsigned long long) offset, count);
2061
2062         err = 0;
2063         clnt = fid->clnt;
2064
2065         rsize = fid->iounit;
2066         if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2067                 rsize = clnt->msize - P9_READDIRHDRSZ;
2068
2069         if (count < rsize)
2070                 rsize = count;
2071
2072         /* Don't bother zerocopy for small IO (< 1024) */
2073         if (clnt->trans_mod->zc_request && rsize > 1024) {
2074                 /*
2075                  * response header len is 11
2076                  * PDU Header(7) + IO Size (4)
2077                  */
2078                 req = p9_client_zc_rpc(clnt, P9_TREADDIR, data, NULL, rsize, 0,
2079                                        11, 1, "dqd", fid->fid, offset, rsize);
2080         } else {
2081                 non_zc = 1;
2082                 req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2083                                     offset, rsize);
2084         }
2085         if (IS_ERR(req)) {
2086                 err = PTR_ERR(req);
2087                 goto error;
2088         }
2089
2090         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2091         if (err) {
2092                 trace_9p_protocol_dump(clnt, req->rc);
2093                 goto free_and_error;
2094         }
2095
2096         p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2097
2098         if (non_zc)
2099                 memmove(data, dataptr, count);
2100
2101         p9_free_req(clnt, req);
2102         return count;
2103
2104 free_and_error:
2105         p9_free_req(clnt, req);
2106 error:
2107         return err;
2108 }
2109 EXPORT_SYMBOL(p9_client_readdir);
2110
2111 int p9_client_mknod_dotl(struct p9_fid *fid, char *name, int mode,
2112                         dev_t rdev, kgid_t gid, struct p9_qid *qid)
2113 {
2114         int err;
2115         struct p9_client *clnt;
2116         struct p9_req_t *req;
2117
2118         err = 0;
2119         clnt = fid->clnt;
2120         p9_debug(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2121                 "minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2122         req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddg", fid->fid, name, mode,
2123                 MAJOR(rdev), MINOR(rdev), gid);
2124         if (IS_ERR(req))
2125                 return PTR_ERR(req);
2126
2127         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2128         if (err) {
2129                 trace_9p_protocol_dump(clnt, req->rc);
2130                 goto error;
2131         }
2132         p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2133                                 (unsigned long long)qid->path, qid->version);
2134
2135 error:
2136         p9_free_req(clnt, req);
2137         return err;
2138
2139 }
2140 EXPORT_SYMBOL(p9_client_mknod_dotl);
2141
2142 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
2143                                 kgid_t gid, struct p9_qid *qid)
2144 {
2145         int err;
2146         struct p9_client *clnt;
2147         struct p9_req_t *req;
2148
2149         err = 0;
2150         clnt = fid->clnt;
2151         p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2152                  fid->fid, name, mode, from_kgid(&init_user_ns, gid));
2153         req = p9_client_rpc(clnt, P9_TMKDIR, "dsdg", fid->fid, name, mode,
2154                 gid);
2155         if (IS_ERR(req))
2156                 return PTR_ERR(req);
2157
2158         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2159         if (err) {
2160                 trace_9p_protocol_dump(clnt, req->rc);
2161                 goto error;
2162         }
2163         p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2164                                 (unsigned long long)qid->path, qid->version);
2165
2166 error:
2167         p9_free_req(clnt, req);
2168         return err;
2169
2170 }
2171 EXPORT_SYMBOL(p9_client_mkdir_dotl);
2172
2173 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2174 {
2175         int err;
2176         struct p9_client *clnt;
2177         struct p9_req_t *req;
2178
2179         err = 0;
2180         clnt = fid->clnt;
2181         p9_debug(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2182                         "start %lld length %lld proc_id %d client_id %s\n",
2183                         fid->fid, flock->type, flock->flags, flock->start,
2184                         flock->length, flock->proc_id, flock->client_id);
2185
2186         req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2187                                 flock->flags, flock->start, flock->length,
2188                                         flock->proc_id, flock->client_id);
2189
2190         if (IS_ERR(req))
2191                 return PTR_ERR(req);
2192
2193         err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2194         if (err) {
2195                 trace_9p_protocol_dump(clnt, req->rc);
2196                 goto error;
2197         }
2198         p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2199 error:
2200         p9_free_req(clnt, req);
2201         return err;
2202
2203 }
2204 EXPORT_SYMBOL(p9_client_lock_dotl);
2205
2206 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2207 {
2208         int err;
2209         struct p9_client *clnt;
2210         struct p9_req_t *req;
2211
2212         err = 0;
2213         clnt = fid->clnt;
2214         p9_debug(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
2215                 "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2216                 glock->start, glock->length, glock->proc_id, glock->client_id);
2217
2218         req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
2219                 glock->start, glock->length, glock->proc_id, glock->client_id);
2220
2221         if (IS_ERR(req))
2222                 return PTR_ERR(req);
2223
2224         err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2225                         &glock->start, &glock->length, &glock->proc_id,
2226                         &glock->client_id);
2227         if (err) {
2228                 trace_9p_protocol_dump(clnt, req->rc);
2229                 goto error;
2230         }
2231         p9_debug(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2232                 "proc_id %d client_id %s\n", glock->type, glock->start,
2233                 glock->length, glock->proc_id, glock->client_id);
2234 error:
2235         p9_free_req(clnt, req);
2236         return err;
2237 }
2238 EXPORT_SYMBOL(p9_client_getlock_dotl);
2239
2240 int p9_client_readlink(struct p9_fid *fid, char **target)
2241 {
2242         int err;
2243         struct p9_client *clnt;
2244         struct p9_req_t *req;
2245
2246         err = 0;
2247         clnt = fid->clnt;
2248         p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2249
2250         req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2251         if (IS_ERR(req))
2252                 return PTR_ERR(req);
2253
2254         err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2255         if (err) {
2256                 trace_9p_protocol_dump(clnt, req->rc);
2257                 goto error;
2258         }
2259         p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2260 error:
2261         p9_free_req(clnt, req);
2262         return err;
2263 }
2264 EXPORT_SYMBOL(p9_client_readlink);