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         if (oldreq->status == REQ_STATUS_FLSH) {
 664                 spin_lock(&c->lock);
 665                 list_del(&oldreq->req_list);
 666                 spin_unlock(&c->lock);
 667         }
 668
 669         p9_free_req(c, req);
 670         return 0;
 671 }
 672
 673 static struct p9_req_t *p9_client_prepare_req(struct p9_client *c,
 674                                               int8_t type, int req_size,
 675                                               const char *fmt, va_list ap)
 676 {
 677         int tag, err;
 678         struct p9_req_t *req;
 679
 680         p9_debug(P9_DEBUG_MUX, "client %p op %d\n", c, type);
 681
 682         /* we allow for any status other than disconnected */
 683         if (c->status == Disconnected)
 684                 return ERR_PTR(-EIO);
 685
 686         /* if status is begin_disconnected we allow only clunk request */
 687         if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
 688                 return ERR_PTR(-EIO);
 689
 690         tag = P9_NOTAG;
 691         if (type != P9_TVERSION) {
 692                 tag = p9_idpool_get(c->tagpool);
 693                 if (tag < 0)
 694                         return ERR_PTR(-ENOMEM);
 695         }
 696
 697         req = p9_tag_alloc(c, tag, req_size);
 698         if (IS_ERR(req))
 699                 return req;
 700
 701         /* marshall the data */
 702         p9pdu_prepare(req->tc, tag, type);
 703         err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
 704         if (err)
 705                 goto reterr;
 706         p9pdu_finalize(c, req->tc);
 707         trace_9p_client_req(c, type, tag);
 708         return req;
 709 reterr:
 710         p9_free_req(c, req);
 711         return ERR_PTR(err);
 712 }
 713
 714 /**
 715  * p9_client_rpc - issue a request and wait for a response
 716  * @c: client session
 717  * @type: type of request
 718  * @fmt: protocol format string (see protocol.c)
 719  *
 720  * Returns request structure (which client must free using p9_free_req)
 721  */
 722
 723 static struct p9_req_t *
 724 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 725 {
 726         va_list ap;
 727         int sigpending, err;
 728         unsigned long flags;
 729         struct p9_req_t *req;
 730
 731         va_start(ap, fmt);
 732         req = p9_client_prepare_req(c, type, c->msize, fmt, ap);
 733         va_end(ap);
 734         if (IS_ERR(req))
 735                 return req;
 736
 737         if (signal_pending(current)) {
 738                 sigpending = 1;
 739                 clear_thread_flag(TIF_SIGPENDING);
 740         } else
 741                 sigpending = 0;
 742
 743         err = c->trans_mod->request(c, req);
 744         if (err < 0) {
 745                 if (err != -ERESTARTSYS && err != -EFAULT)
 746                         c->status = Disconnected;
 747                 goto reterr;
 748         }
 749 again:
 750         /* Wait for the response */
 751         err = wait_event_interruptible(*req->wq,
 752                                        req->status >= REQ_STATUS_RCVD);
 753
 754         if ((err == -ERESTARTSYS) && (c->status == Connected)
 755                                   && (type == P9_TFLUSH)) {
 756                 sigpending = 1;
 757                 clear_thread_flag(TIF_SIGPENDING);
 758                 goto again;
 759         }
 760
 761         if (req->status == REQ_STATUS_ERROR) {
 762                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 763                 err = req->t_err;
 764         }
 765         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 766                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 767                 sigpending = 1;
 768                 clear_thread_flag(TIF_SIGPENDING);
 769
 770                 if (c->trans_mod->cancel(c, req))
 771                         p9_client_flush(c, req);
 772
 773                 /* if we received the response anyway, don't signal error */
 774                 if (req->status == REQ_STATUS_RCVD)
 775                         err = 0;
 776         }
 777         if (sigpending) {
 778                 spin_lock_irqsave(&current->sighand->siglock, flags);
 779                 recalc_sigpending();
 780                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 781         }
 782         if (err < 0)
 783                 goto reterr;
 784
 785         err = p9_check_errors(c, req);
 786         trace_9p_client_res(c, type, req->rc->tag, err);
 787         if (!err)
 788                 return req;
 789 reterr:
 790         p9_free_req(c, req);
 791         return ERR_PTR(safe_errno(err));
 792 }
 793
 794 /**
 795  * p9_client_zc_rpc - issue a request and wait for a response
 796  * @c: client session
 797  * @type: type of request
 798  * @uidata: user bffer that should be ued for zero copy read
 799  * @uodata: user buffer that shoud be user for zero copy write
 800  * @inlen: read buffer size
 801  * @olen: write buffer size
 802  * @hdrlen: reader header size, This is the size of response protocol data
 803  * @fmt: protocol format string (see protocol.c)
 804  *
 805  * Returns request structure (which client must free using p9_free_req)
 806  */
 807 static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
 808                                          char *uidata, char *uodata,
 809                                          int inlen, int olen, int in_hdrlen,
 810                                          int kern_buf, const char *fmt, ...)
 811 {
 812         va_list ap;
 813         int sigpending, err;
 814         unsigned long flags;
 815         struct p9_req_t *req;
 816
 817         va_start(ap, fmt);
 818         /*
 819          * We allocate a inline protocol data of only 4k bytes.
 820          * The actual content is passed in zero-copy fashion.
 821          */
 822         req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, fmt, ap);
 823         va_end(ap);
 824         if (IS_ERR(req))
 825                 return req;
 826
 827         if (signal_pending(current)) {
 828                 sigpending = 1;
 829                 clear_thread_flag(TIF_SIGPENDING);
 830         } else
 831                 sigpending = 0;
 832
 833         /* If we are called with KERNEL_DS force kern_buf */
 834         if (segment_eq(get_fs(), KERNEL_DS))
 835                 kern_buf = 1;
 836
 837         err = c->trans_mod->zc_request(c, req, uidata, uodata,
 838                                        inlen, olen, in_hdrlen, kern_buf);
 839         if (err < 0) {
 840                 if (err == -EIO)
 841                         c->status = Disconnected;
 842                 goto reterr;
 843         }
 844         if (req->status == REQ_STATUS_ERROR) {
 845                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 846                 err = req->t_err;
 847         }
 848         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 849                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 850                 sigpending = 1;
 851                 clear_thread_flag(TIF_SIGPENDING);
 852
 853                 if (c->trans_mod->cancel(c, req))
 854                         p9_client_flush(c, req);
 855
 856                 /* if we received the response anyway, don't signal error */
 857                 if (req->status == REQ_STATUS_RCVD)
 858                         err = 0;
 859         }
 860         if (sigpending) {
 861                 spin_lock_irqsave(&current->sighand->siglock, flags);
 862                 recalc_sigpending();
 863                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 864         }
 865         if (err < 0)
 866                 goto reterr;
 867
 868         err = p9_check_zc_errors(c, req, uidata, in_hdrlen, kern_buf);
 869         trace_9p_client_res(c, type, req->rc->tag, err);
 870         if (!err)
 871                 return req;
 872 reterr:
 873         p9_free_req(c, req);
 874         return ERR_PTR(safe_errno(err));
 875 }
 876
 877 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 878 {
 879         int ret;
 880         struct p9_fid *fid;
 881         unsigned long flags;
 882
 883         p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt);
 884         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
 885         if (!fid)
 886                 return ERR_PTR(-ENOMEM);
 887
 888         ret = p9_idpool_get(clnt->fidpool);
 889         if (ret < 0) {
 890                 ret = -ENOSPC;
 891                 goto error;
 892         }
 893         fid->fid = ret;
 894
 895         memset(&fid->qid, 0, sizeof(struct p9_qid));
 896         fid->mode = -1;
 897         fid->uid = current_fsuid();
 898         fid->clnt = clnt;
 899         fid->rdir = NULL;
 900         spin_lock_irqsave(&clnt->lock, flags);
 901         list_add(&fid->flist, &clnt->fidlist);
 902         spin_unlock_irqrestore(&clnt->lock, flags);
 903
 904         return fid;
 905
 906 error:
 907         kfree(fid);
 908         return ERR_PTR(ret);
 909 }
 910
 911 static void p9_fid_destroy(struct p9_fid *fid)
 912 {
 913         struct p9_client *clnt;
 914         unsigned long flags;
 915
 916         p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
 917         clnt = fid->clnt;
 918         p9_idpool_put(fid->fid, clnt->fidpool);
 919         spin_lock_irqsave(&clnt->lock, flags);
 920         list_del(&fid->flist);
 921         spin_unlock_irqrestore(&clnt->lock, flags);
 922         kfree(fid->rdir);
 923         kfree(fid);
 924 }
 925
 926 static int p9_client_version(struct p9_client *c)
 927 {
 928         int err = 0;
 929         struct p9_req_t *req;
 930         char *version;
 931         int msize;
 932
 933         p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
 934                  c->msize, c->proto_version);
 935
 936         switch (c->proto_version) {
 937         case p9_proto_2000L:
 938                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 939                                         c->msize, "9P2000.L");
 940                 break;
 941         case p9_proto_2000u:
 942                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 943                                         c->msize, "9P2000.u");
 944                 break;
 945         case p9_proto_legacy:
 946                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 947                                         c->msize, "9P2000");
 948                 break;
 949         default:
 950                 return -EINVAL;
 951                 break;
 952         }
 953
 954         if (IS_ERR(req))
 955                 return PTR_ERR(req);
 956
 957         err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
 958         if (err) {
 959                 p9_debug(P9_DEBUG_9P, "version error %d\n", err);
 960                 trace_9p_protocol_dump(c, req->rc);
 961                 goto error;
 962         }
 963
 964         p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
 965         if (!strncmp(version, "9P2000.L", 8))
 966                 c->proto_version = p9_proto_2000L;
 967         else if (!strncmp(version, "9P2000.u", 8))
 968                 c->proto_version = p9_proto_2000u;
 969         else if (!strncmp(version, "9P2000", 6))
 970                 c->proto_version = p9_proto_legacy;
 971         else {
 972                 err = -EREMOTEIO;
 973                 goto error;
 974         }
 975
 976         if (msize < c->msize)
 977                 c->msize = msize;
 978
 979 error:
 980         kfree(version);
 981         p9_free_req(c, req);
 982
 983         return err;
 984 }
 985
 986 struct p9_client *p9_client_create(const char *dev_name, char *options)
 987 {
 988         int err;
 989         struct p9_client *clnt;
 990
 991         err = 0;
 992         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
 993         if (!clnt)
 994                 return ERR_PTR(-ENOMEM);
 995
 996         clnt->trans_mod = NULL;
 997         clnt->trans = NULL;
 998         spin_lock_init(&clnt->lock);
 999         INIT_LIST_HEAD(&clnt->fidlist);
1000
1001         err = p9_tag_init(clnt);
1002         if (err < 0)
1003                 goto free_client;
1004
1005         err = parse_opts(options, clnt);
1006         if (err < 0)
1007                 goto destroy_tagpool;
1008
1009         if (!clnt->trans_mod)
1010                 clnt->trans_mod = v9fs_get_trans_by_name("virtio");
1011
1012         if (!clnt->trans_mod)
1013                 clnt->trans_mod = v9fs_get_default_trans();
1014
1015         if (clnt->trans_mod == NULL) {
1016                 err = -EPROTONOSUPPORT;
1017                 p9_debug(P9_DEBUG_ERROR,
1018                          "No transport defined or default transport\n");
1019                 goto destroy_tagpool;
1020         }
1021
1022         clnt->fidpool = p9_idpool_create();
1023         if (IS_ERR(clnt->fidpool)) {
1024                 err = PTR_ERR(clnt->fidpool);
1025                 goto put_trans;
1026         }
1027
1028         p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1029                  clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1030
1031         err = clnt->trans_mod->create(clnt, dev_name, options);
1032         if (err)
1033                 goto destroy_fidpool;
1034
1035         if (clnt->msize > clnt->trans_mod->maxsize)
1036                 clnt->msize = clnt->trans_mod->maxsize;
1037
1038         err = p9_client_version(clnt);
1039         if (err)
1040                 goto close_trans;
1041
1042         return clnt;
1043
1044 close_trans:
1045         clnt->trans_mod->close(clnt);
1046 destroy_fidpool:
1047         p9_idpool_destroy(clnt->fidpool);
1048 put_trans:
1049         v9fs_put_trans(clnt->trans_mod);
1050 destroy_tagpool:
1051         p9_idpool_destroy(clnt->tagpool);
1052 free_client:
1053         kfree(clnt);
1054         return ERR_PTR(err);
1055 }
1056 EXPORT_SYMBOL(p9_client_create);
1057
1058 void p9_client_destroy(struct p9_client *clnt)
1059 {
1060         struct p9_fid *fid, *fidptr;
1061
1062         p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
1063
1064         if (clnt->trans_mod)
1065                 clnt->trans_mod->close(clnt);
1066
1067         v9fs_put_trans(clnt->trans_mod);
1068
1069         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
1070                 pr_info("Found fid %d not clunked\n", fid->fid);
1071                 p9_fid_destroy(fid);
1072         }
1073
1074         if (clnt->fidpool)
1075                 p9_idpool_destroy(clnt->fidpool);
1076
1077         p9_tag_cleanup(clnt);
1078
1079         kfree(clnt);
1080 }
1081 EXPORT_SYMBOL(p9_client_destroy);
1082
1083 void p9_client_disconnect(struct p9_client *clnt)
1084 {
1085         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1086         clnt->status = Disconnected;
1087 }
1088 EXPORT_SYMBOL(p9_client_disconnect);
1089
1090 void p9_client_begin_disconnect(struct p9_client *clnt)
1091 {
1092         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1093         clnt->status = BeginDisconnect;
1094 }
1095 EXPORT_SYMBOL(p9_client_begin_disconnect);
1096
1097 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1098         char *uname, kuid_t n_uname, char *aname)
1099 {
1100         int err = 0;
1101         struct p9_req_t *req;
1102         struct p9_fid *fid;
1103         struct p9_qid qid;
1104
1105
1106         p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1107                  afid ? afid->fid : -1, uname, aname);
1108         fid = p9_fid_create(clnt);
1109         if (IS_ERR(fid)) {
1110                 err = PTR_ERR(fid);
1111                 fid = NULL;
1112                 goto error;
1113         }
1114
1115         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?u", fid->fid,
1116                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1117         if (IS_ERR(req)) {
1118                 err = PTR_ERR(req);
1119                 goto error;
1120         }
1121
1122         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
1123         if (err) {
1124                 trace_9p_protocol_dump(clnt, req->rc);
1125                 p9_free_req(clnt, req);
1126                 goto error;
1127         }
1128
1129         p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1130                  qid.type, (unsigned long long)qid.path, qid.version);
1131
1132         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1133
1134         p9_free_req(clnt, req);
1135         return fid;
1136
1137 error:
1138         if (fid)
1139                 p9_fid_destroy(fid);
1140         return ERR_PTR(err);
1141 }
1142 EXPORT_SYMBOL(p9_client_attach);
1143
1144 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1145                 char **wnames, int clone)
1146 {
1147         int err;
1148         struct p9_client *clnt;
1149         struct p9_fid *fid;
1150         struct p9_qid *wqids;
1151         struct p9_req_t *req;
1152         uint16_t nwqids, count;
1153
1154         err = 0;
1155         wqids = NULL;
1156         clnt = oldfid->clnt;
1157         if (clone) {
1158                 fid = p9_fid_create(clnt);
1159                 if (IS_ERR(fid)) {
1160                         err = PTR_ERR(fid);
1161                         fid = NULL;
1162                         goto error;
1163                 }
1164
1165                 fid->uid = oldfid->uid;
1166         } else
1167                 fid = oldfid;
1168
1169
1170         p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1171                  oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1172
1173         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1174                                                                 nwname, wnames);
1175         if (IS_ERR(req)) {
1176                 err = PTR_ERR(req);
1177                 goto error;
1178         }
1179
1180         err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1181         if (err) {
1182                 trace_9p_protocol_dump(clnt, req->rc);
1183                 p9_free_req(clnt, req);
1184                 goto clunk_fid;
1185         }
1186         p9_free_req(clnt, req);
1187
1188         p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1189
1190         if (nwqids != nwname) {
1191                 err = -ENOENT;
1192                 goto clunk_fid;
1193         }
1194
1195         for (count = 0; count < nwqids; count++)
1196                 p9_debug(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
1197                         count, wqids[count].type,
1198                         (unsigned long long)wqids[count].path,
1199                         wqids[count].version);
1200
1201         if (nwname)
1202                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1203         else
1204                 fid->qid = oldfid->qid;
1205
1206         kfree(wqids);
1207         return fid;
1208
1209 clunk_fid:
1210         kfree(wqids);
1211         p9_client_clunk(fid);
1212         fid = NULL;
1213
1214 error:
1215         if (fid && (fid != oldfid))
1216                 p9_fid_destroy(fid);
1217
1218         return ERR_PTR(err);
1219 }
1220 EXPORT_SYMBOL(p9_client_walk);
1221
1222 int p9_client_open(struct p9_fid *fid, int mode)
1223 {
1224         int err;
1225         struct p9_client *clnt;
1226         struct p9_req_t *req;
1227         struct p9_qid qid;
1228         int iounit;
1229
1230         clnt = fid->clnt;
1231         p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1232                 p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1233         err = 0;
1234
1235         if (fid->mode != -1)
1236                 return -EINVAL;
1237
1238         if (p9_is_proto_dotl(clnt))
1239                 req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1240         else
1241                 req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1242         if (IS_ERR(req)) {
1243                 err = PTR_ERR(req);
1244                 goto error;
1245         }
1246
1247         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1248         if (err) {
1249                 trace_9p_protocol_dump(clnt, req->rc);
1250                 goto free_and_error;
1251         }
1252
1253         p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1254                 p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1255                 (unsigned long long)qid.path, qid.version, iounit);
1256
1257         fid->mode = mode;
1258         fid->iounit = iounit;
1259
1260 free_and_error:
1261         p9_free_req(clnt, req);
1262 error:
1263         return err;
1264 }
1265 EXPORT_SYMBOL(p9_client_open);
1266
1267 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
1268                 kgid_t gid, struct p9_qid *qid)
1269 {
1270         int err = 0;
1271         struct p9_client *clnt;
1272         struct p9_req_t *req;
1273         int iounit;
1274
1275         p9_debug(P9_DEBUG_9P,
1276                         ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1277                         ofid->fid, name, flags, mode,
1278                         from_kgid(&init_user_ns, gid));
1279         clnt = ofid->clnt;
1280
1281         if (ofid->mode != -1)
1282                 return -EINVAL;
1283
1284         req = p9_client_rpc(clnt, P9_TLCREATE, "dsddg", ofid->fid, name, flags,
1285                         mode, gid);
1286         if (IS_ERR(req)) {
1287                 err = PTR_ERR(req);
1288                 goto error;
1289         }
1290
1291         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1292         if (err) {
1293                 trace_9p_protocol_dump(clnt, req->rc);
1294                 goto free_and_error;
1295         }
1296
1297         p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1298                         qid->type,
1299                         (unsigned long long)qid->path,
1300                         qid->version, iounit);
1301
1302         ofid->mode = mode;
1303         ofid->iounit = iounit;
1304
1305 free_and_error:
1306         p9_free_req(clnt, req);
1307 error:
1308         return err;
1309 }
1310 EXPORT_SYMBOL(p9_client_create_dotl);
1311
1312 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1313                      char *extension)
1314 {
1315         int err;
1316         struct p9_client *clnt;
1317         struct p9_req_t *req;
1318         struct p9_qid qid;
1319         int iounit;
1320
1321         p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1322                                                 fid->fid, name, perm, mode);
1323         err = 0;
1324         clnt = fid->clnt;
1325
1326         if (fid->mode != -1)
1327                 return -EINVAL;
1328
1329         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1330                                 mode, extension);
1331         if (IS_ERR(req)) {
1332                 err = PTR_ERR(req);
1333                 goto error;
1334         }
1335
1336         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1337         if (err) {
1338                 trace_9p_protocol_dump(clnt, req->rc);
1339                 goto free_and_error;
1340         }
1341
1342         p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1343                                 qid.type,
1344                                 (unsigned long long)qid.path,
1345                                 qid.version, iounit);
1346
1347         fid->mode = mode;
1348         fid->iounit = iounit;
1349
1350 free_and_error:
1351         p9_free_req(clnt, req);
1352 error:
1353         return err;
1354 }
1355 EXPORT_SYMBOL(p9_client_fcreate);
1356
1357 int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, kgid_t gid,
1358                 struct p9_qid *qid)
1359 {
1360         int err = 0;
1361         struct p9_client *clnt;
1362         struct p9_req_t *req;
1363
1364         p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1365                         dfid->fid, name, symtgt);
1366         clnt = dfid->clnt;
1367
1368         req = p9_client_rpc(clnt, P9_TSYMLINK, "dssg", dfid->fid, name, symtgt,
1369                         gid);
1370         if (IS_ERR(req)) {
1371                 err = PTR_ERR(req);
1372                 goto error;
1373         }
1374
1375         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1376         if (err) {
1377                 trace_9p_protocol_dump(clnt, req->rc);
1378                 goto free_and_error;
1379         }
1380
1381         p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1382                         qid->type, (unsigned long long)qid->path, qid->version);
1383
1384 free_and_error:
1385         p9_free_req(clnt, req);
1386 error:
1387         return err;
1388 }
1389 EXPORT_SYMBOL(p9_client_symlink);
1390
1391 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
1392 {
1393         struct p9_client *clnt;
1394         struct p9_req_t *req;
1395
1396         p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1397                         dfid->fid, oldfid->fid, newname);
1398         clnt = dfid->clnt;
1399         req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1400                         newname);
1401         if (IS_ERR(req))
1402                 return PTR_ERR(req);
1403
1404         p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
1405         p9_free_req(clnt, req);
1406         return 0;
1407 }
1408 EXPORT_SYMBOL(p9_client_link);
1409
1410 int p9_client_fsync(struct p9_fid *fid, int datasync)
1411 {
1412         int err;
1413         struct p9_client *clnt;
1414         struct p9_req_t *req;
1415
1416         p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1417                         fid->fid, datasync);
1418         err = 0;
1419         clnt = fid->clnt;
1420
1421         req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1422         if (IS_ERR(req)) {
1423                 err = PTR_ERR(req);
1424                 goto error;
1425         }
1426
1427         p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1428
1429         p9_free_req(clnt, req);
1430
1431 error:
1432         return err;
1433 }
1434 EXPORT_SYMBOL(p9_client_fsync);
1435
1436 int p9_client_clunk(struct p9_fid *fid)
1437 {
1438         int err;
1439         struct p9_client *clnt;
1440         struct p9_req_t *req;
1441         int retries = 0;
1442
1443         if (!fid) {
1444                 pr_warn("%s (%d): Trying to clunk with NULL fid\n",
1445                         __func__, task_pid_nr(current));
1446                 dump_stack();
1447                 return 0;
1448         }
1449
1450 again:
1451         p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n", fid->fid,
1452                                                                 retries);
1453         err = 0;
1454         clnt = fid->clnt;
1455
1456         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1457         if (IS_ERR(req)) {
1458                 err = PTR_ERR(req);
1459                 goto error;
1460         }
1461
1462         p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1463
1464         p9_free_req(clnt, req);
1465 error:
1466         /*
1467          * Fid is not valid even after a failed clunk
1468          * If interrupted, retry once then give up and
1469          * leak fid until umount.
1470          */
1471         if (err == -ERESTARTSYS) {
1472                 if (retries++ == 0)
1473                         goto again;
1474         } else
1475                 p9_fid_destroy(fid);
1476         return err;
1477 }
1478 EXPORT_SYMBOL(p9_client_clunk);
1479
1480 int p9_client_remove(struct p9_fid *fid)
1481 {
1482         int err;
1483         struct p9_client *clnt;
1484         struct p9_req_t *req;
1485
1486         p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1487         err = 0;
1488         clnt = fid->clnt;
1489
1490         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1491         if (IS_ERR(req)) {
1492                 err = PTR_ERR(req);
1493                 goto error;
1494         }
1495
1496         p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1497
1498         p9_free_req(clnt, req);
1499 error:
1500         if (err == -ERESTARTSYS)
1501                 p9_client_clunk(fid);
1502         else
1503                 p9_fid_destroy(fid);
1504         return err;
1505 }
1506 EXPORT_SYMBOL(p9_client_remove);
1507
1508 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1509 {
1510         int err = 0;
1511         struct p9_req_t *req;
1512         struct p9_client *clnt;
1513
1514         p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1515                    dfid->fid, name, flags);
1516
1517         clnt = dfid->clnt;
1518         req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1519         if (IS_ERR(req)) {
1520                 err = PTR_ERR(req);
1521                 goto error;
1522         }
1523         p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1524
1525         p9_free_req(clnt, req);
1526 error:
1527         return err;
1528 }
1529 EXPORT_SYMBOL(p9_client_unlinkat);
1530
1531 int
1532 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1533                                                                 u32 count)
1534 {
1535         char *dataptr;
1536         int kernel_buf = 0;
1537         struct p9_req_t *req;
1538         struct p9_client *clnt;
1539         int err, rsize, non_zc = 0;
1540
1541
1542         p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
1543                    fid->fid, (unsigned long long) offset, count);
1544         err = 0;
1545         clnt = fid->clnt;
1546
1547         rsize = fid->iounit;
1548         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1549                 rsize = clnt->msize - P9_IOHDRSZ;
1550
1551         if (count < rsize)
1552                 rsize = count;
1553
1554         /* Don't bother zerocopy for small IO (< 1024) */
1555         if (clnt->trans_mod->zc_request && rsize > 1024) {
1556                 char *indata;
1557                 if (data) {
1558                         kernel_buf = 1;
1559                         indata = data;
1560                 } else
1561                         indata = (__force char *)udata;
1562                 /*
1563                  * response header len is 11
1564                  * PDU Header(7) + IO Size (4)
1565                  */
1566                 req = p9_client_zc_rpc(clnt, P9_TREAD, indata, NULL, rsize, 0,
1567                                        11, kernel_buf, "dqd", fid->fid,
1568                                        offset, rsize);
1569         } else {
1570                 non_zc = 1;
1571                 req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1572                                     rsize);
1573         }
1574         if (IS_ERR(req)) {
1575                 err = PTR_ERR(req);
1576                 goto error;
1577         }
1578
1579         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1580         if (err) {
1581                 trace_9p_protocol_dump(clnt, req->rc);
1582                 goto free_and_error;
1583         }
1584
1585         p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1586
1587         if (non_zc) {
1588                 if (data) {
1589                         memmove(data, dataptr, count);
1590                 } else {
1591                         err = copy_to_user(udata, dataptr, count);
1592                         if (err) {
1593                                 err = -EFAULT;
1594                                 goto free_and_error;
1595                         }
1596                 }
1597         }
1598         p9_free_req(clnt, req);
1599         return count;
1600
1601 free_and_error:
1602         p9_free_req(clnt, req);
1603 error:
1604         return err;
1605 }
1606 EXPORT_SYMBOL(p9_client_read);
1607
1608 int
1609 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1610                                                         u64 offset, u32 count)
1611 {
1612         int err, rsize;
1613         int kernel_buf = 0;
1614         struct p9_client *clnt;
1615         struct p9_req_t *req;
1616
1617         p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1618                                 fid->fid, (unsigned long long) offset, count);
1619         err = 0;
1620         clnt = fid->clnt;
1621
1622         rsize = fid->iounit;
1623         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1624                 rsize = clnt->msize - P9_IOHDRSZ;
1625
1626         if (count < rsize)
1627                 rsize = count;
1628
1629         /* Don't bother zerocopy for small IO (< 1024) */
1630         if (clnt->trans_mod->zc_request && rsize > 1024) {
1631                 char *odata;
1632                 if (data) {
1633                         kernel_buf = 1;
1634                         odata = data;
1635                 } else
1636                         odata = (char *)udata;
1637                 req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, odata, 0, rsize,
1638                                        P9_ZC_HDR_SZ, kernel_buf, "dqd",
1639                                        fid->fid, offset, rsize);
1640         } else {
1641                 if (data)
1642                         req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid,
1643                                             offset, rsize, data);
1644                 else
1645                         req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid,
1646                                             offset, rsize, udata);
1647         }
1648         if (IS_ERR(req)) {
1649                 err = PTR_ERR(req);
1650                 goto error;
1651         }
1652
1653         err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1654         if (err) {
1655                 trace_9p_protocol_dump(clnt, req->rc);
1656                 goto free_and_error;
1657         }
1658
1659         p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1660
1661         p9_free_req(clnt, req);
1662         return count;
1663
1664 free_and_error:
1665         p9_free_req(clnt, req);
1666 error:
1667         return err;
1668 }
1669 EXPORT_SYMBOL(p9_client_write);
1670
1671 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1672 {
1673         int err;
1674         struct p9_client *clnt;
1675         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1676         struct p9_req_t *req;
1677         u16 ignored;
1678
1679         p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1680
1681         if (!ret)
1682                 return ERR_PTR(-ENOMEM);
1683
1684         err = 0;
1685         clnt = fid->clnt;
1686
1687         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1688         if (IS_ERR(req)) {
1689                 err = PTR_ERR(req);
1690                 goto error;
1691         }
1692
1693         err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1694         if (err) {
1695                 trace_9p_protocol_dump(clnt, req->rc);
1696                 p9_free_req(clnt, req);
1697                 goto error;
1698         }
1699
1700         p9_debug(P9_DEBUG_9P,
1701                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1702                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1703                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1704                 "<<<    uid=%d gid=%d n_muid=%d\n",
1705                 ret->size, ret->type, ret->dev, ret->qid.type,
1706                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1707                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1708                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1709                 from_kuid(&init_user_ns, ret->n_uid),
1710                 from_kgid(&init_user_ns, ret->n_gid),
1711                 from_kuid(&init_user_ns, ret->n_muid));
1712
1713         p9_free_req(clnt, req);
1714         return ret;
1715
1716 error:
1717         kfree(ret);
1718         return ERR_PTR(err);
1719 }
1720 EXPORT_SYMBOL(p9_client_stat);
1721
1722 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1723                                                         u64 request_mask)
1724 {
1725         int err;
1726         struct p9_client *clnt;
1727         struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1728                                                                 GFP_KERNEL);
1729         struct p9_req_t *req;
1730
1731         p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1732                                                         fid->fid, request_mask);
1733
1734         if (!ret)
1735                 return ERR_PTR(-ENOMEM);
1736
1737         err = 0;
1738         clnt = fid->clnt;
1739
1740         req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1741         if (IS_ERR(req)) {
1742                 err = PTR_ERR(req);
1743                 goto error;
1744         }
1745
1746         err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1747         if (err) {
1748                 trace_9p_protocol_dump(clnt, req->rc);
1749                 p9_free_req(clnt, req);
1750                 goto error;
1751         }
1752
1753         p9_debug(P9_DEBUG_9P,
1754                 "<<< RGETATTR st_result_mask=%lld\n"
1755                 "<<< qid=%x.%llx.%x\n"
1756                 "<<< st_mode=%8.8x st_nlink=%llu\n"
1757                 "<<< st_uid=%d st_gid=%d\n"
1758                 "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1759                 "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1760                 "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1761                 "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1762                 "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1763                 "<<< st_gen=%lld st_data_version=%lld",
1764                 ret->st_result_mask, ret->qid.type, ret->qid.path,
1765                 ret->qid.version, ret->st_mode, ret->st_nlink,
1766                 from_kuid(&init_user_ns, ret->st_uid),
1767                 from_kgid(&init_user_ns, ret->st_gid),
1768                 ret->st_rdev, ret->st_size, ret->st_blksize,
1769                 ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1770                 ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1771                 ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1772                 ret->st_gen, ret->st_data_version);
1773
1774         p9_free_req(clnt, req);
1775         return ret;
1776
1777 error:
1778         kfree(ret);
1779         return ERR_PTR(err);
1780 }
1781 EXPORT_SYMBOL(p9_client_getattr_dotl);
1782
1783 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1784 {
1785         int ret;
1786
1787         /* NOTE: size shouldn't include its own length */
1788         /* size[2] type[2] dev[4] qid[13] */
1789         /* mode[4] atime[4] mtime[4] length[8]*/
1790         /* name[s] uid[s] gid[s] muid[s] */
1791         ret = 2+4+13+4+4+4+8+2+2+2+2;
1792
1793         if (wst->name)
1794                 ret += strlen(wst->name);
1795         if (wst->uid)
1796                 ret += strlen(wst->uid);
1797         if (wst->gid)
1798                 ret += strlen(wst->gid);
1799         if (wst->muid)
1800                 ret += strlen(wst->muid);
1801
1802         if ((proto_version == p9_proto_2000u) ||
1803                 (proto_version == p9_proto_2000L)) {
1804                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1805                 if (wst->extension)
1806                         ret += strlen(wst->extension);
1807         }
1808
1809         return ret;
1810 }
1811
1812 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1813 {
1814         int err;
1815         struct p9_req_t *req;
1816         struct p9_client *clnt;
1817
1818         err = 0;
1819         clnt = fid->clnt;
1820         wst->size = p9_client_statsize(wst, clnt->proto_version);
1821         p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1822         p9_debug(P9_DEBUG_9P,
1823                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1824                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1825                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1826                 "     uid=%d gid=%d n_muid=%d\n",
1827                 wst->size, wst->type, wst->dev, wst->qid.type,
1828                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1829                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1830                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1831                 from_kuid(&init_user_ns, wst->n_uid),
1832                 from_kgid(&init_user_ns, wst->n_gid),
1833                 from_kuid(&init_user_ns, wst->n_muid));
1834
1835         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1836         if (IS_ERR(req)) {
1837                 err = PTR_ERR(req);
1838                 goto error;
1839         }
1840
1841         p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1842
1843         p9_free_req(clnt, req);
1844 error:
1845         return err;
1846 }
1847 EXPORT_SYMBOL(p9_client_wstat);
1848
1849 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1850 {
1851         int err;
1852         struct p9_req_t *req;
1853         struct p9_client *clnt;
1854
1855         err = 0;
1856         clnt = fid->clnt;
1857         p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1858         p9_debug(P9_DEBUG_9P,
1859                 "    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1860                 "    atime_sec=%lld atime_nsec=%lld\n"
1861                 "    mtime_sec=%lld mtime_nsec=%lld\n",
1862                 p9attr->valid, p9attr->mode,
1863                 from_kuid(&init_user_ns, p9attr->uid),
1864                 from_kgid(&init_user_ns, p9attr->gid),
1865                 p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1866                 p9attr->mtime_sec, p9attr->mtime_nsec);
1867
1868         req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1869
1870         if (IS_ERR(req)) {
1871                 err = PTR_ERR(req);
1872                 goto error;
1873         }
1874         p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1875         p9_free_req(clnt, req);
1876 error:
1877         return err;
1878 }
1879 EXPORT_SYMBOL(p9_client_setattr);
1880
1881 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1882 {
1883         int err;
1884         struct p9_req_t *req;
1885         struct p9_client *clnt;
1886
1887         err = 0;
1888         clnt = fid->clnt;
1889
1890         p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1891
1892         req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1893         if (IS_ERR(req)) {
1894                 err = PTR_ERR(req);
1895                 goto error;
1896         }
1897
1898         err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1899                 &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1900                 &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1901         if (err) {
1902                 trace_9p_protocol_dump(clnt, req->rc);
1903                 p9_free_req(clnt, req);
1904                 goto error;
1905         }
1906
1907         p9_debug(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1908                 "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1909                 "fsid %llu namelen %ld\n",
1910                 fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1911                 sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1912                 sb->fsid, (long int)sb->namelen);
1913
1914         p9_free_req(clnt, req);
1915 error:
1916         return err;
1917 }
1918 EXPORT_SYMBOL(p9_client_statfs);
1919
1920 int p9_client_rename(struct p9_fid *fid,
1921                      struct p9_fid *newdirfid, const char *name)
1922 {
1923         int err;
1924         struct p9_req_t *req;
1925         struct p9_client *clnt;
1926
1927         err = 0;
1928         clnt = fid->clnt;
1929
1930         p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1931                         fid->fid, newdirfid->fid, name);
1932
1933         req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1934                         newdirfid->fid, name);
1935         if (IS_ERR(req)) {
1936                 err = PTR_ERR(req);
1937                 goto error;
1938         }
1939
1940         p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1941
1942         p9_free_req(clnt, req);
1943 error:
1944         return err;
1945 }
1946 EXPORT_SYMBOL(p9_client_rename);
1947
1948 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1949                        struct p9_fid *newdirfid, const char *new_name)
1950 {
1951         int err;
1952         struct p9_req_t *req;
1953         struct p9_client *clnt;
1954
1955         err = 0;
1956         clnt = olddirfid->clnt;
1957
1958         p9_debug(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1959                    " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1960                    newdirfid->fid, new_name);
1961
1962         req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1963                             old_name, newdirfid->fid, new_name);
1964         if (IS_ERR(req)) {
1965                 err = PTR_ERR(req);
1966                 goto error;
1967         }
1968
1969         p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
1970                    newdirfid->fid, new_name);
1971
1972         p9_free_req(clnt, req);
1973 error:
1974         return err;
1975 }
1976 EXPORT_SYMBOL(p9_client_renameat);
1977
1978 /*
1979  * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1980  */
1981 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1982                                 const char *attr_name, u64 *attr_size)
1983 {
1984         int err;
1985         struct p9_req_t *req;
1986         struct p9_client *clnt;
1987         struct p9_fid *attr_fid;
1988
1989         err = 0;
1990         clnt = file_fid->clnt;
1991         attr_fid = p9_fid_create(clnt);
1992         if (IS_ERR(attr_fid)) {
1993                 err = PTR_ERR(attr_fid);
1994                 attr_fid = NULL;
1995                 goto error;
1996         }
1997         p9_debug(P9_DEBUG_9P,
1998                 ">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
1999                 file_fid->fid, attr_fid->fid, attr_name);
2000
2001         req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
2002                         file_fid->fid, attr_fid->fid, attr_name);
2003         if (IS_ERR(req)) {
2004                 err = PTR_ERR(req);
2005                 goto error;
2006         }
2007         err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
2008         if (err) {
2009                 trace_9p_protocol_dump(clnt, req->rc);
2010                 p9_free_req(clnt, req);
2011                 goto clunk_fid;
2012         }
2013         p9_free_req(clnt, req);
2014         p9_debug(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
2015                 attr_fid->fid, *attr_size);
2016         return attr_fid;
2017 clunk_fid:
2018         p9_client_clunk(attr_fid);
2019         attr_fid = NULL;
2020 error:
2021         if (attr_fid && (attr_fid != file_fid))
2022                 p9_fid_destroy(attr_fid);
2023
2024         return ERR_PTR(err);
2025 }
2026 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
2027
2028 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
2029                         u64 attr_size, int flags)
2030 {
2031         int err;
2032         struct p9_req_t *req;
2033         struct p9_client *clnt;
2034
2035         p9_debug(P9_DEBUG_9P,
2036                 ">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
2037                 fid->fid, name, (long long)attr_size, flags);
2038         err = 0;
2039         clnt = fid->clnt;
2040         req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2041                         fid->fid, name, attr_size, flags);
2042         if (IS_ERR(req)) {
2043                 err = PTR_ERR(req);
2044                 goto error;
2045         }
2046         p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2047         p9_free_req(clnt, req);
2048 error:
2049         return err;
2050 }
2051 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2052
2053 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2054 {
2055         int err, rsize, non_zc = 0;
2056         struct p9_client *clnt;
2057         struct p9_req_t *req;
2058         char *dataptr;
2059
2060         p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2061                                 fid->fid, (unsigned long long) offset, count);
2062
2063         err = 0;
2064         clnt = fid->clnt;
2065
2066         rsize = fid->iounit;
2067         if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2068                 rsize = clnt->msize - P9_READDIRHDRSZ;
2069
2070         if (count < rsize)
2071                 rsize = count;
2072
2073         /* Don't bother zerocopy for small IO (< 1024) */
2074         if (clnt->trans_mod->zc_request && rsize > 1024) {
2075                 /*
2076                  * response header len is 11
2077                  * PDU Header(7) + IO Size (4)
2078                  */
2079                 req = p9_client_zc_rpc(clnt, P9_TREADDIR, data, NULL, rsize, 0,
2080                                        11, 1, "dqd", fid->fid, offset, rsize);
2081         } else {
2082                 non_zc = 1;
2083                 req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2084                                     offset, rsize);
2085         }
2086         if (IS_ERR(req)) {
2087                 err = PTR_ERR(req);
2088                 goto error;
2089         }
2090
2091         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2092         if (err) {
2093                 trace_9p_protocol_dump(clnt, req->rc);
2094                 goto free_and_error;
2095         }
2096
2097         p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2098
2099         if (non_zc)
2100                 memmove(data, dataptr, count);
2101
2102         p9_free_req(clnt, req);
2103         return count;
2104
2105 free_and_error:
2106         p9_free_req(clnt, req);
2107 error:
2108         return err;
2109 }
2110 EXPORT_SYMBOL(p9_client_readdir);
2111
2112 int p9_client_mknod_dotl(struct p9_fid *fid, char *name, int mode,
2113                         dev_t rdev, kgid_t gid, struct p9_qid *qid)
2114 {
2115         int err;
2116         struct p9_client *clnt;
2117         struct p9_req_t *req;
2118
2119         err = 0;
2120         clnt = fid->clnt;
2121         p9_debug(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2122                 "minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2123         req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddg", fid->fid, name, mode,
2124                 MAJOR(rdev), MINOR(rdev), gid);
2125         if (IS_ERR(req))
2126                 return PTR_ERR(req);
2127
2128         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2129         if (err) {
2130                 trace_9p_protocol_dump(clnt, req->rc);
2131                 goto error;
2132         }
2133         p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2134                                 (unsigned long long)qid->path, qid->version);
2135
2136 error:
2137         p9_free_req(clnt, req);
2138         return err;
2139
2140 }
2141 EXPORT_SYMBOL(p9_client_mknod_dotl);
2142
2143 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
2144                                 kgid_t gid, struct p9_qid *qid)
2145 {
2146         int err;
2147         struct p9_client *clnt;
2148         struct p9_req_t *req;
2149
2150         err = 0;
2151         clnt = fid->clnt;
2152         p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2153                  fid->fid, name, mode, from_kgid(&init_user_ns, gid));
2154         req = p9_client_rpc(clnt, P9_TMKDIR, "dsdg", fid->fid, name, mode,
2155                 gid);
2156         if (IS_ERR(req))
2157                 return PTR_ERR(req);
2158
2159         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2160         if (err) {
2161                 trace_9p_protocol_dump(clnt, req->rc);
2162                 goto error;
2163         }
2164         p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2165                                 (unsigned long long)qid->path, qid->version);
2166
2167 error:
2168         p9_free_req(clnt, req);
2169         return err;
2170
2171 }
2172 EXPORT_SYMBOL(p9_client_mkdir_dotl);
2173
2174 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2175 {
2176         int err;
2177         struct p9_client *clnt;
2178         struct p9_req_t *req;
2179
2180         err = 0;
2181         clnt = fid->clnt;
2182         p9_debug(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2183                         "start %lld length %lld proc_id %d client_id %s\n",
2184                         fid->fid, flock->type, flock->flags, flock->start,
2185                         flock->length, flock->proc_id, flock->client_id);
2186
2187         req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2188                                 flock->flags, flock->start, flock->length,
2189                                         flock->proc_id, flock->client_id);
2190
2191         if (IS_ERR(req))
2192                 return PTR_ERR(req);
2193
2194         err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2195         if (err) {
2196                 trace_9p_protocol_dump(clnt, req->rc);
2197                 goto error;
2198         }
2199         p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2200 error:
2201         p9_free_req(clnt, req);
2202         return err;
2203
2204 }
2205 EXPORT_SYMBOL(p9_client_lock_dotl);
2206
2207 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2208 {
2209         int err;
2210         struct p9_client *clnt;
2211         struct p9_req_t *req;
2212
2213         err = 0;
2214         clnt = fid->clnt;
2215         p9_debug(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
2216                 "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2217                 glock->start, glock->length, glock->proc_id, glock->client_id);
2218
2219         req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
2220                 glock->start, glock->length, glock->proc_id, glock->client_id);
2221
2222         if (IS_ERR(req))
2223                 return PTR_ERR(req);
2224
2225         err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2226                         &glock->start, &glock->length, &glock->proc_id,
2227                         &glock->client_id);
2228         if (err) {
2229                 trace_9p_protocol_dump(clnt, req->rc);
2230                 goto error;
2231         }
2232         p9_debug(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2233                 "proc_id %d client_id %s\n", glock->type, glock->start,
2234                 glock->length, glock->proc_id, glock->client_id);
2235 error:
2236         p9_free_req(clnt, req);
2237         return err;
2238 }
2239 EXPORT_SYMBOL(p9_client_getlock_dotl);
2240
2241 int p9_client_readlink(struct p9_fid *fid, char **target)
2242 {
2243         int err;
2244         struct p9_client *clnt;
2245         struct p9_req_t *req;
2246
2247         err = 0;
2248         clnt = fid->clnt;
2249         p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2250
2251         req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2252         if (IS_ERR(req))
2253                 return PTR_ERR(req);
2254
2255         err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2256         if (err) {
2257                 trace_9p_protocol_dump(clnt, req->rc);
2258                 goto error;
2259         }
2260         p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2261 error:
2262         p9_free_req(clnt, req);
2263         return err;
2264 }
2265 EXPORT_SYMBOL(p9_client_readlink);