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         char *client_id;
 991
 992         err = 0;
 993         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
 994         if (!clnt)
 995                 return ERR_PTR(-ENOMEM);
 996
 997         clnt->trans_mod = NULL;
 998         clnt->trans = NULL;
 999
1000         client_id = utsname()->nodename;
1001         memcpy(clnt->name, client_id, strlen(client_id) + 1);
1002
1003         spin_lock_init(&clnt->lock);
1004         INIT_LIST_HEAD(&clnt->fidlist);
1005
1006         err = p9_tag_init(clnt);
1007         if (err < 0)
1008                 goto free_client;
1009
1010         err = parse_opts(options, clnt);
1011         if (err < 0)
1012                 goto destroy_tagpool;
1013
1014         if (!clnt->trans_mod)
1015                 clnt->trans_mod = v9fs_get_trans_by_name("virtio");
1016
1017         if (!clnt->trans_mod)
1018                 clnt->trans_mod = v9fs_get_default_trans();
1019
1020         if (clnt->trans_mod == NULL) {
1021                 err = -EPROTONOSUPPORT;
1022                 p9_debug(P9_DEBUG_ERROR,
1023                          "No transport defined or default transport\n");
1024                 goto destroy_tagpool;
1025         }
1026
1027         clnt->fidpool = p9_idpool_create();
1028         if (IS_ERR(clnt->fidpool)) {
1029                 err = PTR_ERR(clnt->fidpool);
1030                 goto put_trans;
1031         }
1032
1033         p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1034                  clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1035
1036         err = clnt->trans_mod->create(clnt, dev_name, options);
1037         if (err)
1038                 goto destroy_fidpool;
1039
1040         if (clnt->msize > clnt->trans_mod->maxsize)
1041                 clnt->msize = clnt->trans_mod->maxsize;
1042
1043         err = p9_client_version(clnt);
1044         if (err)
1045                 goto close_trans;
1046
1047         return clnt;
1048
1049 close_trans:
1050         clnt->trans_mod->close(clnt);
1051 destroy_fidpool:
1052         p9_idpool_destroy(clnt->fidpool);
1053 put_trans:
1054         v9fs_put_trans(clnt->trans_mod);
1055 destroy_tagpool:
1056         p9_idpool_destroy(clnt->tagpool);
1057 free_client:
1058         kfree(clnt);
1059         return ERR_PTR(err);
1060 }
1061 EXPORT_SYMBOL(p9_client_create);
1062
1063 void p9_client_destroy(struct p9_client *clnt)
1064 {
1065         struct p9_fid *fid, *fidptr;
1066
1067         p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
1068
1069         if (clnt->trans_mod)
1070                 clnt->trans_mod->close(clnt);
1071
1072         v9fs_put_trans(clnt->trans_mod);
1073
1074         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
1075                 pr_info("Found fid %d not clunked\n", fid->fid);
1076                 p9_fid_destroy(fid);
1077         }
1078
1079         if (clnt->fidpool)
1080                 p9_idpool_destroy(clnt->fidpool);
1081
1082         p9_tag_cleanup(clnt);
1083
1084         kfree(clnt);
1085 }
1086 EXPORT_SYMBOL(p9_client_destroy);
1087
1088 void p9_client_disconnect(struct p9_client *clnt)
1089 {
1090         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1091         clnt->status = Disconnected;
1092 }
1093 EXPORT_SYMBOL(p9_client_disconnect);
1094
1095 void p9_client_begin_disconnect(struct p9_client *clnt)
1096 {
1097         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1098         clnt->status = BeginDisconnect;
1099 }
1100 EXPORT_SYMBOL(p9_client_begin_disconnect);
1101
1102 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1103         char *uname, kuid_t n_uname, char *aname)
1104 {
1105         int err = 0;
1106         struct p9_req_t *req;
1107         struct p9_fid *fid;
1108         struct p9_qid qid;
1109
1110
1111         p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1112                  afid ? afid->fid : -1, uname, aname);
1113         fid = p9_fid_create(clnt);
1114         if (IS_ERR(fid)) {
1115                 err = PTR_ERR(fid);
1116                 fid = NULL;
1117                 goto error;
1118         }
1119
1120         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?u", fid->fid,
1121                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1122         if (IS_ERR(req)) {
1123                 err = PTR_ERR(req);
1124                 goto error;
1125         }
1126
1127         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
1128         if (err) {
1129                 trace_9p_protocol_dump(clnt, req->rc);
1130                 p9_free_req(clnt, req);
1131                 goto error;
1132         }
1133
1134         p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1135                  qid.type, (unsigned long long)qid.path, qid.version);
1136
1137         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1138
1139         p9_free_req(clnt, req);
1140         return fid;
1141
1142 error:
1143         if (fid)
1144                 p9_fid_destroy(fid);
1145         return ERR_PTR(err);
1146 }
1147 EXPORT_SYMBOL(p9_client_attach);
1148
1149 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1150                 char **wnames, int clone)
1151 {
1152         int err;
1153         struct p9_client *clnt;
1154         struct p9_fid *fid;
1155         struct p9_qid *wqids;
1156         struct p9_req_t *req;
1157         uint16_t nwqids, count;
1158
1159         err = 0;
1160         wqids = NULL;
1161         clnt = oldfid->clnt;
1162         if (clone) {
1163                 fid = p9_fid_create(clnt);
1164                 if (IS_ERR(fid)) {
1165                         err = PTR_ERR(fid);
1166                         fid = NULL;
1167                         goto error;
1168                 }
1169
1170                 fid->uid = oldfid->uid;
1171         } else
1172                 fid = oldfid;
1173
1174
1175         p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1176                  oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1177
1178         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1179                                                                 nwname, wnames);
1180         if (IS_ERR(req)) {
1181                 err = PTR_ERR(req);
1182                 goto error;
1183         }
1184
1185         err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1186         if (err) {
1187                 trace_9p_protocol_dump(clnt, req->rc);
1188                 p9_free_req(clnt, req);
1189                 goto clunk_fid;
1190         }
1191         p9_free_req(clnt, req);
1192
1193         p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1194
1195         if (nwqids != nwname) {
1196                 err = -ENOENT;
1197                 goto clunk_fid;
1198         }
1199
1200         for (count = 0; count < nwqids; count++)
1201                 p9_debug(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
1202                         count, wqids[count].type,
1203                         (unsigned long long)wqids[count].path,
1204                         wqids[count].version);
1205
1206         if (nwname)
1207                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1208         else
1209                 fid->qid = oldfid->qid;
1210
1211         kfree(wqids);
1212         return fid;
1213
1214 clunk_fid:
1215         kfree(wqids);
1216         p9_client_clunk(fid);
1217         fid = NULL;
1218
1219 error:
1220         if (fid && (fid != oldfid))
1221                 p9_fid_destroy(fid);
1222
1223         return ERR_PTR(err);
1224 }
1225 EXPORT_SYMBOL(p9_client_walk);
1226
1227 int p9_client_open(struct p9_fid *fid, int mode)
1228 {
1229         int err;
1230         struct p9_client *clnt;
1231         struct p9_req_t *req;
1232         struct p9_qid qid;
1233         int iounit;
1234
1235         clnt = fid->clnt;
1236         p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1237                 p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1238         err = 0;
1239
1240         if (fid->mode != -1)
1241                 return -EINVAL;
1242
1243         if (p9_is_proto_dotl(clnt))
1244                 req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1245         else
1246                 req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1247         if (IS_ERR(req)) {
1248                 err = PTR_ERR(req);
1249                 goto error;
1250         }
1251
1252         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1253         if (err) {
1254                 trace_9p_protocol_dump(clnt, req->rc);
1255                 goto free_and_error;
1256         }
1257
1258         p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1259                 p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1260                 (unsigned long long)qid.path, qid.version, iounit);
1261
1262         fid->mode = mode;
1263         fid->iounit = iounit;
1264
1265 free_and_error:
1266         p9_free_req(clnt, req);
1267 error:
1268         return err;
1269 }
1270 EXPORT_SYMBOL(p9_client_open);
1271
1272 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
1273                 kgid_t gid, struct p9_qid *qid)
1274 {
1275         int err = 0;
1276         struct p9_client *clnt;
1277         struct p9_req_t *req;
1278         int iounit;
1279
1280         p9_debug(P9_DEBUG_9P,
1281                         ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1282                         ofid->fid, name, flags, mode,
1283                         from_kgid(&init_user_ns, gid));
1284         clnt = ofid->clnt;
1285
1286         if (ofid->mode != -1)
1287                 return -EINVAL;
1288
1289         req = p9_client_rpc(clnt, P9_TLCREATE, "dsddg", ofid->fid, name, flags,
1290                         mode, gid);
1291         if (IS_ERR(req)) {
1292                 err = PTR_ERR(req);
1293                 goto error;
1294         }
1295
1296         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1297         if (err) {
1298                 trace_9p_protocol_dump(clnt, req->rc);
1299                 goto free_and_error;
1300         }
1301
1302         p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1303                         qid->type,
1304                         (unsigned long long)qid->path,
1305                         qid->version, iounit);
1306
1307         ofid->mode = mode;
1308         ofid->iounit = iounit;
1309
1310 free_and_error:
1311         p9_free_req(clnt, req);
1312 error:
1313         return err;
1314 }
1315 EXPORT_SYMBOL(p9_client_create_dotl);
1316
1317 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1318                      char *extension)
1319 {
1320         int err;
1321         struct p9_client *clnt;
1322         struct p9_req_t *req;
1323         struct p9_qid qid;
1324         int iounit;
1325
1326         p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1327                                                 fid->fid, name, perm, mode);
1328         err = 0;
1329         clnt = fid->clnt;
1330
1331         if (fid->mode != -1)
1332                 return -EINVAL;
1333
1334         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1335                                 mode, extension);
1336         if (IS_ERR(req)) {
1337                 err = PTR_ERR(req);
1338                 goto error;
1339         }
1340
1341         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1342         if (err) {
1343                 trace_9p_protocol_dump(clnt, req->rc);
1344                 goto free_and_error;
1345         }
1346
1347         p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1348                                 qid.type,
1349                                 (unsigned long long)qid.path,
1350                                 qid.version, iounit);
1351
1352         fid->mode = mode;
1353         fid->iounit = iounit;
1354
1355 free_and_error:
1356         p9_free_req(clnt, req);
1357 error:
1358         return err;
1359 }
1360 EXPORT_SYMBOL(p9_client_fcreate);
1361
1362 int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, kgid_t gid,
1363                 struct p9_qid *qid)
1364 {
1365         int err = 0;
1366         struct p9_client *clnt;
1367         struct p9_req_t *req;
1368
1369         p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1370                         dfid->fid, name, symtgt);
1371         clnt = dfid->clnt;
1372
1373         req = p9_client_rpc(clnt, P9_TSYMLINK, "dssg", dfid->fid, name, symtgt,
1374                         gid);
1375         if (IS_ERR(req)) {
1376                 err = PTR_ERR(req);
1377                 goto error;
1378         }
1379
1380         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1381         if (err) {
1382                 trace_9p_protocol_dump(clnt, req->rc);
1383                 goto free_and_error;
1384         }
1385
1386         p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1387                         qid->type, (unsigned long long)qid->path, qid->version);
1388
1389 free_and_error:
1390         p9_free_req(clnt, req);
1391 error:
1392         return err;
1393 }
1394 EXPORT_SYMBOL(p9_client_symlink);
1395
1396 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
1397 {
1398         struct p9_client *clnt;
1399         struct p9_req_t *req;
1400
1401         p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1402                         dfid->fid, oldfid->fid, newname);
1403         clnt = dfid->clnt;
1404         req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1405                         newname);
1406         if (IS_ERR(req))
1407                 return PTR_ERR(req);
1408
1409         p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
1410         p9_free_req(clnt, req);
1411         return 0;
1412 }
1413 EXPORT_SYMBOL(p9_client_link);
1414
1415 int p9_client_fsync(struct p9_fid *fid, int datasync)
1416 {
1417         int err;
1418         struct p9_client *clnt;
1419         struct p9_req_t *req;
1420
1421         p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1422                         fid->fid, datasync);
1423         err = 0;
1424         clnt = fid->clnt;
1425
1426         req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1427         if (IS_ERR(req)) {
1428                 err = PTR_ERR(req);
1429                 goto error;
1430         }
1431
1432         p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1433
1434         p9_free_req(clnt, req);
1435
1436 error:
1437         return err;
1438 }
1439 EXPORT_SYMBOL(p9_client_fsync);
1440
1441 int p9_client_clunk(struct p9_fid *fid)
1442 {
1443         int err;
1444         struct p9_client *clnt;
1445         struct p9_req_t *req;
1446         int retries = 0;
1447
1448         if (!fid) {
1449                 pr_warn("%s (%d): Trying to clunk with NULL fid\n",
1450                         __func__, task_pid_nr(current));
1451                 dump_stack();
1452                 return 0;
1453         }
1454
1455 again:
1456         p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n", fid->fid,
1457                                                                 retries);
1458         err = 0;
1459         clnt = fid->clnt;
1460
1461         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1462         if (IS_ERR(req)) {
1463                 err = PTR_ERR(req);
1464                 goto error;
1465         }
1466
1467         p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1468
1469         p9_free_req(clnt, req);
1470 error:
1471         /*
1472          * Fid is not valid even after a failed clunk
1473          * If interrupted, retry once then give up and
1474          * leak fid until umount.
1475          */
1476         if (err == -ERESTARTSYS) {
1477                 if (retries++ == 0)
1478                         goto again;
1479         } else
1480                 p9_fid_destroy(fid);
1481         return err;
1482 }
1483 EXPORT_SYMBOL(p9_client_clunk);
1484
1485 int p9_client_remove(struct p9_fid *fid)
1486 {
1487         int err;
1488         struct p9_client *clnt;
1489         struct p9_req_t *req;
1490
1491         p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1492         err = 0;
1493         clnt = fid->clnt;
1494
1495         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1496         if (IS_ERR(req)) {
1497                 err = PTR_ERR(req);
1498                 goto error;
1499         }
1500
1501         p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1502
1503         p9_free_req(clnt, req);
1504 error:
1505         if (err == -ERESTARTSYS)
1506                 p9_client_clunk(fid);
1507         else
1508                 p9_fid_destroy(fid);
1509         return err;
1510 }
1511 EXPORT_SYMBOL(p9_client_remove);
1512
1513 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1514 {
1515         int err = 0;
1516         struct p9_req_t *req;
1517         struct p9_client *clnt;
1518
1519         p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1520                    dfid->fid, name, flags);
1521
1522         clnt = dfid->clnt;
1523         req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1524         if (IS_ERR(req)) {
1525                 err = PTR_ERR(req);
1526                 goto error;
1527         }
1528         p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1529
1530         p9_free_req(clnt, req);
1531 error:
1532         return err;
1533 }
1534 EXPORT_SYMBOL(p9_client_unlinkat);
1535
1536 int
1537 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1538                                                                 u32 count)
1539 {
1540         char *dataptr;
1541         int kernel_buf = 0;
1542         struct p9_req_t *req;
1543         struct p9_client *clnt;
1544         int err, rsize, non_zc = 0;
1545
1546
1547         p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
1548                    fid->fid, (unsigned long long) offset, count);
1549         err = 0;
1550         clnt = fid->clnt;
1551
1552         rsize = fid->iounit;
1553         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1554                 rsize = clnt->msize - P9_IOHDRSZ;
1555
1556         if (count < rsize)
1557                 rsize = count;
1558
1559         /* Don't bother zerocopy for small IO (< 1024) */
1560         if (clnt->trans_mod->zc_request && rsize > 1024) {
1561                 char *indata;
1562                 if (data) {
1563                         kernel_buf = 1;
1564                         indata = data;
1565                 } else
1566                         indata = (__force char *)udata;
1567                 /*
1568                  * response header len is 11
1569                  * PDU Header(7) + IO Size (4)
1570                  */
1571                 req = p9_client_zc_rpc(clnt, P9_TREAD, indata, NULL, rsize, 0,
1572                                        11, kernel_buf, "dqd", fid->fid,
1573                                        offset, rsize);
1574         } else {
1575                 non_zc = 1;
1576                 req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1577                                     rsize);
1578         }
1579         if (IS_ERR(req)) {
1580                 err = PTR_ERR(req);
1581                 goto error;
1582         }
1583
1584         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1585         if (err) {
1586                 trace_9p_protocol_dump(clnt, req->rc);
1587                 goto free_and_error;
1588         }
1589
1590         p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1591
1592         if (non_zc) {
1593                 if (data) {
1594                         memmove(data, dataptr, count);
1595                 } else {
1596                         err = copy_to_user(udata, dataptr, count);
1597                         if (err) {
1598                                 err = -EFAULT;
1599                                 goto free_and_error;
1600                         }
1601                 }
1602         }
1603         p9_free_req(clnt, req);
1604         return count;
1605
1606 free_and_error:
1607         p9_free_req(clnt, req);
1608 error:
1609         return err;
1610 }
1611 EXPORT_SYMBOL(p9_client_read);
1612
1613 int
1614 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1615                                                         u64 offset, u32 count)
1616 {
1617         int err, rsize;
1618         int kernel_buf = 0;
1619         struct p9_client *clnt;
1620         struct p9_req_t *req;
1621
1622         p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1623                                 fid->fid, (unsigned long long) offset, count);
1624         err = 0;
1625         clnt = fid->clnt;
1626
1627         rsize = fid->iounit;
1628         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1629                 rsize = clnt->msize - P9_IOHDRSZ;
1630
1631         if (count < rsize)
1632                 rsize = count;
1633
1634         /* Don't bother zerocopy for small IO (< 1024) */
1635         if (clnt->trans_mod->zc_request && rsize > 1024) {
1636                 char *odata;
1637                 if (data) {
1638                         kernel_buf = 1;
1639                         odata = data;
1640                 } else
1641                         odata = (char *)udata;
1642                 req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, odata, 0, rsize,
1643                                        P9_ZC_HDR_SZ, kernel_buf, "dqd",
1644                                        fid->fid, offset, rsize);
1645         } else {
1646                 if (data)
1647                         req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid,
1648                                             offset, rsize, data);
1649                 else
1650                         req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid,
1651                                             offset, rsize, udata);
1652         }
1653         if (IS_ERR(req)) {
1654                 err = PTR_ERR(req);
1655                 goto error;
1656         }
1657
1658         err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1659         if (err) {
1660                 trace_9p_protocol_dump(clnt, req->rc);
1661                 goto free_and_error;
1662         }
1663
1664         p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1665
1666         p9_free_req(clnt, req);
1667         return count;
1668
1669 free_and_error:
1670         p9_free_req(clnt, req);
1671 error:
1672         return err;
1673 }
1674 EXPORT_SYMBOL(p9_client_write);
1675
1676 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1677 {
1678         int err;
1679         struct p9_client *clnt;
1680         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1681         struct p9_req_t *req;
1682         u16 ignored;
1683
1684         p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1685
1686         if (!ret)
1687                 return ERR_PTR(-ENOMEM);
1688
1689         err = 0;
1690         clnt = fid->clnt;
1691
1692         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1693         if (IS_ERR(req)) {
1694                 err = PTR_ERR(req);
1695                 goto error;
1696         }
1697
1698         err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1699         if (err) {
1700                 trace_9p_protocol_dump(clnt, req->rc);
1701                 p9_free_req(clnt, req);
1702                 goto error;
1703         }
1704
1705         p9_debug(P9_DEBUG_9P,
1706                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1707                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1708                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1709                 "<<<    uid=%d gid=%d n_muid=%d\n",
1710                 ret->size, ret->type, ret->dev, ret->qid.type,
1711                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1712                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1713                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1714                 from_kuid(&init_user_ns, ret->n_uid),
1715                 from_kgid(&init_user_ns, ret->n_gid),
1716                 from_kuid(&init_user_ns, ret->n_muid));
1717
1718         p9_free_req(clnt, req);
1719         return ret;
1720
1721 error:
1722         kfree(ret);
1723         return ERR_PTR(err);
1724 }
1725 EXPORT_SYMBOL(p9_client_stat);
1726
1727 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1728                                                         u64 request_mask)
1729 {
1730         int err;
1731         struct p9_client *clnt;
1732         struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1733                                                                 GFP_KERNEL);
1734         struct p9_req_t *req;
1735
1736         p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1737                                                         fid->fid, request_mask);
1738
1739         if (!ret)
1740                 return ERR_PTR(-ENOMEM);
1741
1742         err = 0;
1743         clnt = fid->clnt;
1744
1745         req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1746         if (IS_ERR(req)) {
1747                 err = PTR_ERR(req);
1748                 goto error;
1749         }
1750
1751         err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1752         if (err) {
1753                 trace_9p_protocol_dump(clnt, req->rc);
1754                 p9_free_req(clnt, req);
1755                 goto error;
1756         }
1757
1758         p9_debug(P9_DEBUG_9P,
1759                 "<<< RGETATTR st_result_mask=%lld\n"
1760                 "<<< qid=%x.%llx.%x\n"
1761                 "<<< st_mode=%8.8x st_nlink=%llu\n"
1762                 "<<< st_uid=%d st_gid=%d\n"
1763                 "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1764                 "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1765                 "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1766                 "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1767                 "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1768                 "<<< st_gen=%lld st_data_version=%lld",
1769                 ret->st_result_mask, ret->qid.type, ret->qid.path,
1770                 ret->qid.version, ret->st_mode, ret->st_nlink,
1771                 from_kuid(&init_user_ns, ret->st_uid),
1772                 from_kgid(&init_user_ns, ret->st_gid),
1773                 ret->st_rdev, ret->st_size, ret->st_blksize,
1774                 ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1775                 ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1776                 ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1777                 ret->st_gen, ret->st_data_version);
1778
1779         p9_free_req(clnt, req);
1780         return ret;
1781
1782 error:
1783         kfree(ret);
1784         return ERR_PTR(err);
1785 }
1786 EXPORT_SYMBOL(p9_client_getattr_dotl);
1787
1788 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1789 {
1790         int ret;
1791
1792         /* NOTE: size shouldn't include its own length */
1793         /* size[2] type[2] dev[4] qid[13] */
1794         /* mode[4] atime[4] mtime[4] length[8]*/
1795         /* name[s] uid[s] gid[s] muid[s] */
1796         ret = 2+4+13+4+4+4+8+2+2+2+2;
1797
1798         if (wst->name)
1799                 ret += strlen(wst->name);
1800         if (wst->uid)
1801                 ret += strlen(wst->uid);
1802         if (wst->gid)
1803                 ret += strlen(wst->gid);
1804         if (wst->muid)
1805                 ret += strlen(wst->muid);
1806
1807         if ((proto_version == p9_proto_2000u) ||
1808                 (proto_version == p9_proto_2000L)) {
1809                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1810                 if (wst->extension)
1811                         ret += strlen(wst->extension);
1812         }
1813
1814         return ret;
1815 }
1816
1817 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1818 {
1819         int err;
1820         struct p9_req_t *req;
1821         struct p9_client *clnt;
1822
1823         err = 0;
1824         clnt = fid->clnt;
1825         wst->size = p9_client_statsize(wst, clnt->proto_version);
1826         p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1827         p9_debug(P9_DEBUG_9P,
1828                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1829                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1830                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1831                 "     uid=%d gid=%d n_muid=%d\n",
1832                 wst->size, wst->type, wst->dev, wst->qid.type,
1833                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1834                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1835                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1836                 from_kuid(&init_user_ns, wst->n_uid),
1837                 from_kgid(&init_user_ns, wst->n_gid),
1838                 from_kuid(&init_user_ns, wst->n_muid));
1839
1840         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1841         if (IS_ERR(req)) {
1842                 err = PTR_ERR(req);
1843                 goto error;
1844         }
1845
1846         p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1847
1848         p9_free_req(clnt, req);
1849 error:
1850         return err;
1851 }
1852 EXPORT_SYMBOL(p9_client_wstat);
1853
1854 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1855 {
1856         int err;
1857         struct p9_req_t *req;
1858         struct p9_client *clnt;
1859
1860         err = 0;
1861         clnt = fid->clnt;
1862         p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1863         p9_debug(P9_DEBUG_9P,
1864                 "    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1865                 "    atime_sec=%lld atime_nsec=%lld\n"
1866                 "    mtime_sec=%lld mtime_nsec=%lld\n",
1867                 p9attr->valid, p9attr->mode,
1868                 from_kuid(&init_user_ns, p9attr->uid),
1869                 from_kgid(&init_user_ns, p9attr->gid),
1870                 p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1871                 p9attr->mtime_sec, p9attr->mtime_nsec);
1872
1873         req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1874
1875         if (IS_ERR(req)) {
1876                 err = PTR_ERR(req);
1877                 goto error;
1878         }
1879         p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1880         p9_free_req(clnt, req);
1881 error:
1882         return err;
1883 }
1884 EXPORT_SYMBOL(p9_client_setattr);
1885
1886 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1887 {
1888         int err;
1889         struct p9_req_t *req;
1890         struct p9_client *clnt;
1891
1892         err = 0;
1893         clnt = fid->clnt;
1894
1895         p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1896
1897         req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1898         if (IS_ERR(req)) {
1899                 err = PTR_ERR(req);
1900                 goto error;
1901         }
1902
1903         err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1904                 &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1905                 &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1906         if (err) {
1907                 trace_9p_protocol_dump(clnt, req->rc);
1908                 p9_free_req(clnt, req);
1909                 goto error;
1910         }
1911
1912         p9_debug(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1913                 "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1914                 "fsid %llu namelen %ld\n",
1915                 fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1916                 sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1917                 sb->fsid, (long int)sb->namelen);
1918
1919         p9_free_req(clnt, req);
1920 error:
1921         return err;
1922 }
1923 EXPORT_SYMBOL(p9_client_statfs);
1924
1925 int p9_client_rename(struct p9_fid *fid,
1926                      struct p9_fid *newdirfid, const char *name)
1927 {
1928         int err;
1929         struct p9_req_t *req;
1930         struct p9_client *clnt;
1931
1932         err = 0;
1933         clnt = fid->clnt;
1934
1935         p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1936                         fid->fid, newdirfid->fid, name);
1937
1938         req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1939                         newdirfid->fid, name);
1940         if (IS_ERR(req)) {
1941                 err = PTR_ERR(req);
1942                 goto error;
1943         }
1944
1945         p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1946
1947         p9_free_req(clnt, req);
1948 error:
1949         return err;
1950 }
1951 EXPORT_SYMBOL(p9_client_rename);
1952
1953 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1954                        struct p9_fid *newdirfid, const char *new_name)
1955 {
1956         int err;
1957         struct p9_req_t *req;
1958         struct p9_client *clnt;
1959
1960         err = 0;
1961         clnt = olddirfid->clnt;
1962
1963         p9_debug(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1964                    " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1965                    newdirfid->fid, new_name);
1966
1967         req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1968                             old_name, newdirfid->fid, new_name);
1969         if (IS_ERR(req)) {
1970                 err = PTR_ERR(req);
1971                 goto error;
1972         }
1973
1974         p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
1975                    newdirfid->fid, new_name);
1976
1977         p9_free_req(clnt, req);
1978 error:
1979         return err;
1980 }
1981 EXPORT_SYMBOL(p9_client_renameat);
1982
1983 /*
1984  * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1985  */
1986 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1987                                 const char *attr_name, u64 *attr_size)
1988 {
1989         int err;
1990         struct p9_req_t *req;
1991         struct p9_client *clnt;
1992         struct p9_fid *attr_fid;
1993
1994         err = 0;
1995         clnt = file_fid->clnt;
1996         attr_fid = p9_fid_create(clnt);
1997         if (IS_ERR(attr_fid)) {
1998                 err = PTR_ERR(attr_fid);
1999                 attr_fid = NULL;
2000                 goto error;
2001         }
2002         p9_debug(P9_DEBUG_9P,
2003                 ">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
2004                 file_fid->fid, attr_fid->fid, attr_name);
2005
2006         req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
2007                         file_fid->fid, attr_fid->fid, attr_name);
2008         if (IS_ERR(req)) {
2009                 err = PTR_ERR(req);
2010                 goto error;
2011         }
2012         err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
2013         if (err) {
2014                 trace_9p_protocol_dump(clnt, req->rc);
2015                 p9_free_req(clnt, req);
2016                 goto clunk_fid;
2017         }
2018         p9_free_req(clnt, req);
2019         p9_debug(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
2020                 attr_fid->fid, *attr_size);
2021         return attr_fid;
2022 clunk_fid:
2023         p9_client_clunk(attr_fid);
2024         attr_fid = NULL;
2025 error:
2026         if (attr_fid && (attr_fid != file_fid))
2027                 p9_fid_destroy(attr_fid);
2028
2029         return ERR_PTR(err);
2030 }
2031 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
2032
2033 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
2034                         u64 attr_size, int flags)
2035 {
2036         int err;
2037         struct p9_req_t *req;
2038         struct p9_client *clnt;
2039
2040         p9_debug(P9_DEBUG_9P,
2041                 ">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
2042                 fid->fid, name, (long long)attr_size, flags);
2043         err = 0;
2044         clnt = fid->clnt;
2045         req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2046                         fid->fid, name, attr_size, flags);
2047         if (IS_ERR(req)) {
2048                 err = PTR_ERR(req);
2049                 goto error;
2050         }
2051         p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2052         p9_free_req(clnt, req);
2053 error:
2054         return err;
2055 }
2056 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2057
2058 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2059 {
2060         int err, rsize, non_zc = 0;
2061         struct p9_client *clnt;
2062         struct p9_req_t *req;
2063         char *dataptr;
2064
2065         p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2066                                 fid->fid, (unsigned long long) offset, count);
2067
2068         err = 0;
2069         clnt = fid->clnt;
2070
2071         rsize = fid->iounit;
2072         if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2073                 rsize = clnt->msize - P9_READDIRHDRSZ;
2074
2075         if (count < rsize)
2076                 rsize = count;
2077
2078         /* Don't bother zerocopy for small IO (< 1024) */
2079         if (clnt->trans_mod->zc_request && rsize > 1024) {
2080                 /*
2081                  * response header len is 11
2082                  * PDU Header(7) + IO Size (4)
2083                  */
2084                 req = p9_client_zc_rpc(clnt, P9_TREADDIR, data, NULL, rsize, 0,
2085                                        11, 1, "dqd", fid->fid, offset, rsize);
2086         } else {
2087                 non_zc = 1;
2088                 req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2089                                     offset, rsize);
2090         }
2091         if (IS_ERR(req)) {
2092                 err = PTR_ERR(req);
2093                 goto error;
2094         }
2095
2096         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2097         if (err) {
2098                 trace_9p_protocol_dump(clnt, req->rc);
2099                 goto free_and_error;
2100         }
2101
2102         p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2103
2104         if (non_zc)
2105                 memmove(data, dataptr, count);
2106
2107         p9_free_req(clnt, req);
2108         return count;
2109
2110 free_and_error:
2111         p9_free_req(clnt, req);
2112 error:
2113         return err;
2114 }
2115 EXPORT_SYMBOL(p9_client_readdir);
2116
2117 int p9_client_mknod_dotl(struct p9_fid *fid, char *name, int mode,
2118                         dev_t rdev, kgid_t gid, struct p9_qid *qid)
2119 {
2120         int err;
2121         struct p9_client *clnt;
2122         struct p9_req_t *req;
2123
2124         err = 0;
2125         clnt = fid->clnt;
2126         p9_debug(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2127                 "minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2128         req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddg", fid->fid, name, mode,
2129                 MAJOR(rdev), MINOR(rdev), gid);
2130         if (IS_ERR(req))
2131                 return PTR_ERR(req);
2132
2133         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2134         if (err) {
2135                 trace_9p_protocol_dump(clnt, req->rc);
2136                 goto error;
2137         }
2138         p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2139                                 (unsigned long long)qid->path, qid->version);
2140
2141 error:
2142         p9_free_req(clnt, req);
2143         return err;
2144
2145 }
2146 EXPORT_SYMBOL(p9_client_mknod_dotl);
2147
2148 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
2149                                 kgid_t gid, struct p9_qid *qid)
2150 {
2151         int err;
2152         struct p9_client *clnt;
2153         struct p9_req_t *req;
2154
2155         err = 0;
2156         clnt = fid->clnt;
2157         p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2158                  fid->fid, name, mode, from_kgid(&init_user_ns, gid));
2159         req = p9_client_rpc(clnt, P9_TMKDIR, "dsdg", fid->fid, name, mode,
2160                 gid);
2161         if (IS_ERR(req))
2162                 return PTR_ERR(req);
2163
2164         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2165         if (err) {
2166                 trace_9p_protocol_dump(clnt, req->rc);
2167                 goto error;
2168         }
2169         p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2170                                 (unsigned long long)qid->path, qid->version);
2171
2172 error:
2173         p9_free_req(clnt, req);
2174         return err;
2175
2176 }
2177 EXPORT_SYMBOL(p9_client_mkdir_dotl);
2178
2179 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2180 {
2181         int err;
2182         struct p9_client *clnt;
2183         struct p9_req_t *req;
2184
2185         err = 0;
2186         clnt = fid->clnt;
2187         p9_debug(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2188                         "start %lld length %lld proc_id %d client_id %s\n",
2189                         fid->fid, flock->type, flock->flags, flock->start,
2190                         flock->length, flock->proc_id, flock->client_id);
2191
2192         req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2193                                 flock->flags, flock->start, flock->length,
2194                                         flock->proc_id, flock->client_id);
2195
2196         if (IS_ERR(req))
2197                 return PTR_ERR(req);
2198
2199         err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2200         if (err) {
2201                 trace_9p_protocol_dump(clnt, req->rc);
2202                 goto error;
2203         }
2204         p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2205 error:
2206         p9_free_req(clnt, req);
2207         return err;
2208
2209 }
2210 EXPORT_SYMBOL(p9_client_lock_dotl);
2211
2212 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2213 {
2214         int err;
2215         struct p9_client *clnt;
2216         struct p9_req_t *req;
2217
2218         err = 0;
2219         clnt = fid->clnt;
2220         p9_debug(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
2221                 "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2222                 glock->start, glock->length, glock->proc_id, glock->client_id);
2223
2224         req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
2225                 glock->start, glock->length, glock->proc_id, glock->client_id);
2226
2227         if (IS_ERR(req))
2228                 return PTR_ERR(req);
2229
2230         err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2231                         &glock->start, &glock->length, &glock->proc_id,
2232                         &glock->client_id);
2233         if (err) {
2234                 trace_9p_protocol_dump(clnt, req->rc);
2235                 goto error;
2236         }
2237         p9_debug(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2238                 "proc_id %d client_id %s\n", glock->type, glock->start,
2239                 glock->length, glock->proc_id, glock->client_id);
2240 error:
2241         p9_free_req(clnt, req);
2242         return err;
2243 }
2244 EXPORT_SYMBOL(p9_client_getlock_dotl);
2245
2246 int p9_client_readlink(struct p9_fid *fid, char **target)
2247 {
2248         int err;
2249         struct p9_client *clnt;
2250         struct p9_req_t *req;
2251
2252         err = 0;
2253         clnt = fid->clnt;
2254         p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2255
2256         req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2257         if (IS_ERR(req))
2258                 return PTR_ERR(req);
2259
2260         err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2261         if (err) {
2262                 trace_9p_protocol_dump(clnt, req->rc);
2263                 goto error;
2264         }
2265         p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2266 error:
2267         p9_free_req(clnt, req);
2268         return err;
2269 }
2270 EXPORT_SYMBOL(p9_client_readlink);