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/signal.h>
  36 #include <linux/uaccess.h>
  37 #include <linux/uio.h>
  38 #include <net/9p/9p.h>
  39 #include <linux/parser.h>
  40 #include <linux/seq_file.h>
  41 #include <net/9p/client.h>
  42 #include <net/9p/transport.h>
  43 #include "protocol.h"
  44
  45 #define CREATE_TRACE_POINTS
  46 #include <trace/events/9p.h>
  47
  48 /*
  49   * Client Option Parsing (code inspired by NFS code)
  50   *  - a little lazy - parse all client options
  51   */
  52
  53 enum {
  54         Opt_msize,
  55         Opt_trans,
  56         Opt_legacy,
  57         Opt_version,
  58         Opt_err,
  59 };
  60
  61 static const match_table_t tokens = {
  62         {Opt_msize, "msize=%u"},
  63         {Opt_legacy, "noextend"},
  64         {Opt_trans, "trans=%s"},
  65         {Opt_version, "version=%s"},
  66         {Opt_err, NULL},
  67 };
  68
  69 inline int p9_is_proto_dotl(struct p9_client *clnt)
  70 {
  71         return clnt->proto_version == p9_proto_2000L;
  72 }
  73 EXPORT_SYMBOL(p9_is_proto_dotl);
  74
  75 inline int p9_is_proto_dotu(struct p9_client *clnt)
  76 {
  77         return clnt->proto_version == p9_proto_2000u;
  78 }
  79 EXPORT_SYMBOL(p9_is_proto_dotu);
  80
  81 int p9_show_client_options(struct seq_file *m, struct p9_client *clnt)
  82 {
  83         if (clnt->msize != 8192)
  84                 seq_printf(m, ",msize=%u", clnt->msize);
  85         seq_printf(m, ",trans=%s", clnt->trans_mod->name);
  86
  87         switch (clnt->proto_version) {
  88         case p9_proto_legacy:
  89                 seq_puts(m, ",noextend");
  90                 break;
  91         case p9_proto_2000u:
  92                 seq_puts(m, ",version=9p2000.u");
  93                 break;
  94         case p9_proto_2000L:
  95                 /* Default */
  96                 break;
  97         }
  98
  99         if (clnt->trans_mod->show_options)
 100                 return clnt->trans_mod->show_options(m, clnt);
 101         return 0;
 102 }
 103 EXPORT_SYMBOL(p9_show_client_options);
 104
 105 /*
 106  * Some error codes are taken directly from the server replies,
 107  * make sure they are valid.
 108  */
 109 static int safe_errno(int err)
 110 {
 111         if ((err > 0) || (err < -MAX_ERRNO)) {
 112                 p9_debug(P9_DEBUG_ERROR, "Invalid error code %d\n", err);
 113                 return -EPROTO;
 114         }
 115         return err;
 116 }
 117
 118
 119 /* Interpret mount option for protocol version */
 120 static int get_protocol_version(char *s)
 121 {
 122         int version = -EINVAL;
 123
 124         if (!strcmp(s, "9p2000")) {
 125                 version = p9_proto_legacy;
 126                 p9_debug(P9_DEBUG_9P, "Protocol version: Legacy\n");
 127         } else if (!strcmp(s, "9p2000.u")) {
 128                 version = p9_proto_2000u;
 129                 p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
 130         } else if (!strcmp(s, "9p2000.L")) {
 131                 version = p9_proto_2000L;
 132                 p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.L\n");
 133         } else
 134                 pr_info("Unknown protocol version %s\n", s);
 135
 136         return version;
 137 }
 138
 139 /**
 140  * parse_options - parse mount options into client structure
 141  * @opts: options string passed from mount
 142  * @clnt: existing v9fs client information
 143  *
 144  * Return 0 upon success, -ERRNO upon failure
 145  */
 146
 147 static int parse_opts(char *opts, struct p9_client *clnt)
 148 {
 149         char *options, *tmp_options;
 150         char *p;
 151         substring_t args[MAX_OPT_ARGS];
 152         int option;
 153         char *s;
 154         int ret = 0;
 155
 156         clnt->proto_version = p9_proto_2000L;
 157         clnt->msize = 8192;
 158
 159         if (!opts)
 160                 return 0;
 161
 162         tmp_options = kstrdup(opts, GFP_KERNEL);
 163         if (!tmp_options) {
 164                 p9_debug(P9_DEBUG_ERROR,
 165                          "failed to allocate copy of option string\n");
 166                 return -ENOMEM;
 167         }
 168         options = tmp_options;
 169
 170         while ((p = strsep(&options, ",")) != NULL) {
 171                 int token, r;
 172                 if (!*p)
 173                         continue;
 174                 token = match_token(p, tokens, args);
 175                 switch (token) {
 176                 case Opt_msize:
 177                         r = match_int(&args[0], &option);
 178                         if (r < 0) {
 179                                 p9_debug(P9_DEBUG_ERROR,
 180                                          "integer field, but no integer?\n");
 181                                 ret = r;
 182                                 continue;
 183                         }
 184                         clnt->msize = option;
 185                         break;
 186                 case Opt_trans:
 187                         s = match_strdup(&args[0]);
 188                         if (!s) {
 189                                 ret = -ENOMEM;
 190                                 p9_debug(P9_DEBUG_ERROR,
 191                                          "problem allocating copy of trans arg\n");
 192                                 goto free_and_return;
 193                          }
 194                         clnt->trans_mod = v9fs_get_trans_by_name(s);
 195                         if (clnt->trans_mod == NULL) {
 196                                 pr_info("Could not find request transport: %s\n",
 197                                         s);
 198                                 ret = -EINVAL;
 199                                 kfree(s);
 200                                 goto free_and_return;
 201                         }
 202                         kfree(s);
 203                         break;
 204                 case Opt_legacy:
 205                         clnt->proto_version = p9_proto_legacy;
 206                         break;
 207                 case Opt_version:
 208                         s = match_strdup(&args[0]);
 209                         if (!s) {
 210                                 ret = -ENOMEM;
 211                                 p9_debug(P9_DEBUG_ERROR,
 212                                          "problem allocating copy of version arg\n");
 213                                 goto free_and_return;
 214                         }
 215                         ret = get_protocol_version(s);
 216                         if (ret == -EINVAL) {
 217                                 kfree(s);
 218                                 goto free_and_return;
 219                         }
 220                         kfree(s);
 221                         clnt->proto_version = ret;
 222                         break;
 223                 default:
 224                         continue;
 225                 }
 226         }
 227
 228 free_and_return:
 229         kfree(tmp_options);
 230         return ret;
 231 }
 232
 233 static struct p9_fcall *p9_fcall_alloc(int alloc_msize)
 234 {
 235         struct p9_fcall *fc;
 236         fc = kmalloc(sizeof(struct p9_fcall) + alloc_msize, GFP_NOFS);
 237         if (!fc)
 238                 return NULL;
 239         fc->capacity = alloc_msize;
 240         fc->sdata = (char *) fc + sizeof(struct p9_fcall);
 241         return fc;
 242 }
 243
 244 /**
 245  * p9_tag_alloc - lookup/allocate a request by tag
 246  * @c: client session to lookup tag within
 247  * @tag: numeric id for transaction
 248  *
 249  * this is a simple array lookup, but will grow the
 250  * request_slots as necessary to accommodate transaction
 251  * ids which did not previously have a slot.
 252  *
 253  * this code relies on the client spinlock to manage locks, its
 254  * possible we should switch to something else, but I'd rather
 255  * stick with something low-overhead for the common case.
 256  *
 257  */
 258
 259 static struct p9_req_t *
 260 p9_tag_alloc(struct p9_client *c, u16 tag, unsigned int max_size)
 261 {
 262         unsigned long flags;
 263         int row, col;
 264         struct p9_req_t *req;
 265         int alloc_msize = min(c->msize, max_size);
 266
 267         /* This looks up the original request by tag so we know which
 268          * buffer to read the data into */
 269         tag++;
 270
 271         if (tag >= c->max_tag) {
 272                 spin_lock_irqsave(&c->lock, flags);
 273                 /* check again since original check was outside of lock */
 274                 while (tag >= c->max_tag) {
 275                         row = (tag / P9_ROW_MAXTAG);
 276                         c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
 277                                         sizeof(struct p9_req_t), GFP_ATOMIC);
 278
 279                         if (!c->reqs[row]) {
 280                                 pr_err("Couldn't grow tag array\n");
 281                                 spin_unlock_irqrestore(&c->lock, flags);
 282                                 return ERR_PTR(-ENOMEM);
 283                         }
 284                         for (col = 0; col < P9_ROW_MAXTAG; col++) {
 285                                 c->reqs[row][col].status = REQ_STATUS_IDLE;
 286                                 c->reqs[row][col].tc = NULL;
 287                         }
 288                         c->max_tag += P9_ROW_MAXTAG;
 289                 }
 290                 spin_unlock_irqrestore(&c->lock, flags);
 291         }
 292         row = tag / P9_ROW_MAXTAG;
 293         col = tag % P9_ROW_MAXTAG;
 294
 295         req = &c->reqs[row][col];
 296         if (!req->wq) {
 297                 req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_NOFS);
 298                 if (!req->wq)
 299                         goto grow_failed;
 300                 init_waitqueue_head(req->wq);
 301         }
 302
 303         if (!req->tc)
 304                 req->tc = p9_fcall_alloc(alloc_msize);
 305         if (!req->rc)
 306                 req->rc = p9_fcall_alloc(alloc_msize);
 307         if (!req->tc || !req->rc)
 308                 goto grow_failed;
 309
 310         p9pdu_reset(req->tc);
 311         p9pdu_reset(req->rc);
 312
 313         req->tc->tag = tag-1;
 314         req->status = REQ_STATUS_ALLOC;
 315
 316         return req;
 317
 318 grow_failed:
 319         pr_err("Couldn't grow tag array\n");
 320         kfree(req->tc);
 321         kfree(req->rc);
 322         kfree(req->wq);
 323         req->tc = req->rc = NULL;
 324         req->wq = NULL;
 325         return ERR_PTR(-ENOMEM);
 326 }
 327
 328 /**
 329  * p9_tag_lookup - lookup a request by tag
 330  * @c: client session to lookup tag within
 331  * @tag: numeric id for transaction
 332  *
 333  */
 334
 335 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
 336 {
 337         int row, col;
 338
 339         /* This looks up the original request by tag so we know which
 340          * buffer to read the data into */
 341         tag++;
 342
 343         if(tag >= c->max_tag)
 344                 return NULL;
 345
 346         row = tag / P9_ROW_MAXTAG;
 347         col = tag % P9_ROW_MAXTAG;
 348
 349         return &c->reqs[row][col];
 350 }
 351 EXPORT_SYMBOL(p9_tag_lookup);
 352
 353 /**
 354  * p9_tag_init - setup tags structure and contents
 355  * @c:  v9fs client struct
 356  *
 357  * This initializes the tags structure for each client instance.
 358  *
 359  */
 360
 361 static int p9_tag_init(struct p9_client *c)
 362 {
 363         int err = 0;
 364
 365         c->tagpool = p9_idpool_create();
 366         if (IS_ERR(c->tagpool)) {
 367                 err = PTR_ERR(c->tagpool);
 368                 goto error;
 369         }
 370         err = p9_idpool_get(c->tagpool); /* reserve tag 0 */
 371         if (err < 0) {
 372                 p9_idpool_destroy(c->tagpool);
 373                 goto error;
 374         }
 375         c->max_tag = 0;
 376 error:
 377         return err;
 378 }
 379
 380 /**
 381  * p9_tag_cleanup - cleans up tags structure and reclaims resources
 382  * @c:  v9fs client struct
 383  *
 384  * This frees resources associated with the tags structure
 385  *
 386  */
 387 static void p9_tag_cleanup(struct p9_client *c)
 388 {
 389         int row, col;
 390
 391         /* check to insure all requests are idle */
 392         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 393                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 394                         if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
 395                                 p9_debug(P9_DEBUG_MUX,
 396                                          "Attempting to cleanup non-free tag %d,%d\n",
 397                                          row, col);
 398                                 /* TODO: delay execution of cleanup */
 399                                 return;
 400                         }
 401                 }
 402         }
 403
 404         if (c->tagpool) {
 405                 p9_idpool_put(0, c->tagpool); /* free reserved tag 0 */
 406                 p9_idpool_destroy(c->tagpool);
 407         }
 408
 409         /* free requests associated with tags */
 410         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 411                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 412                         kfree(c->reqs[row][col].wq);
 413                         kfree(c->reqs[row][col].tc);
 414                         kfree(c->reqs[row][col].rc);
 415                 }
 416                 kfree(c->reqs[row]);
 417         }
 418         c->max_tag = 0;
 419 }
 420
 421 /**
 422  * p9_free_req - free a request and clean-up as necessary
 423  * c: client state
 424  * r: request to release
 425  *
 426  */
 427
 428 static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
 429 {
 430         int tag = r->tc->tag;
 431         p9_debug(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
 432
 433         r->status = REQ_STATUS_IDLE;
 434         if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
 435                 p9_idpool_put(tag, c->tagpool);
 436 }
 437
 438 /**
 439  * p9_client_cb - call back from transport to client
 440  * c: client state
 441  * req: request received
 442  *
 443  */
 444 void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status)
 445 {
 446         p9_debug(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
 447
 448         /*
 449          * This barrier is needed to make sure any change made to req before
 450          * the other thread wakes up will indeed be seen by the waiting side.
 451          */
 452         smp_wmb();
 453         req->status = status;
 454
 455         wake_up(req->wq);
 456         p9_debug(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
 457 }
 458 EXPORT_SYMBOL(p9_client_cb);
 459
 460 /**
 461  * p9_parse_header - parse header arguments out of a packet
 462  * @pdu: packet to parse
 463  * @size: size of packet
 464  * @type: type of request
 465  * @tag: tag of packet
 466  * @rewind: set if we need to rewind offset afterwards
 467  */
 468
 469 int
 470 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
 471                                                                 int rewind)
 472 {
 473         int8_t r_type;
 474         int16_t r_tag;
 475         int32_t r_size;
 476         int offset = pdu->offset;
 477         int err;
 478
 479         pdu->offset = 0;
 480         if (pdu->size == 0)
 481                 pdu->size = 7;
 482
 483         err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
 484         if (err)
 485                 goto rewind_and_exit;
 486
 487         pdu->size = r_size;
 488         pdu->id = r_type;
 489         pdu->tag = r_tag;
 490
 491         p9_debug(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n",
 492                  pdu->size, pdu->id, pdu->tag);
 493
 494         if (type)
 495                 *type = r_type;
 496         if (tag)
 497                 *tag = r_tag;
 498         if (size)
 499                 *size = r_size;
 500
 501
 502 rewind_and_exit:
 503         if (rewind)
 504                 pdu->offset = offset;
 505         return err;
 506 }
 507 EXPORT_SYMBOL(p9_parse_header);
 508
 509 /**
 510  * p9_check_errors - check 9p packet for error return and process it
 511  * @c: current client instance
 512  * @req: request to parse and check for error conditions
 513  *
 514  * returns error code if one is discovered, otherwise returns 0
 515  *
 516  * this will have to be more complicated if we have multiple
 517  * error packet types
 518  */
 519
 520 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 521 {
 522         int8_t type;
 523         int err;
 524         int ecode;
 525
 526         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 527         /*
 528          * dump the response from server
 529          * This should be after check errors which poplulate pdu_fcall.
 530          */
 531         trace_9p_protocol_dump(c, req->rc);
 532         if (err) {
 533                 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 534                 return err;
 535         }
 536         if (type != P9_RERROR && type != P9_RLERROR)
 537                 return 0;
 538
 539         if (!p9_is_proto_dotl(c)) {
 540                 char *ename;
 541                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 542                                   &ename, &ecode);
 543                 if (err)
 544                         goto out_err;
 545
 546                 if (p9_is_proto_dotu(c) && ecode < 512)
 547                         err = -ecode;
 548
 549                 if (!err) {
 550                         err = p9_errstr2errno(ename, strlen(ename));
 551
 552                         p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 553                                  -ecode, ename);
 554                 }
 555                 kfree(ename);
 556         } else {
 557                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 558                 err = -ecode;
 559
 560                 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 561         }
 562
 563         return err;
 564
 565 out_err:
 566         p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 567
 568         return err;
 569 }
 570
 571 /**
 572  * p9_check_zc_errors - check 9p packet for error return and process it
 573  * @c: current client instance
 574  * @req: request to parse and check for error conditions
 575  * @in_hdrlen: Size of response protocol buffer.
 576  *
 577  * returns error code if one is discovered, otherwise returns 0
 578  *
 579  * this will have to be more complicated if we have multiple
 580  * error packet types
 581  */
 582
 583 static int p9_check_zc_errors(struct p9_client *c, struct p9_req_t *req,
 584                               struct iov_iter *uidata, int in_hdrlen)
 585 {
 586         int err;
 587         int ecode;
 588         int8_t type;
 589         char *ename = NULL;
 590
 591         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 592         /*
 593          * dump the response from server
 594          * This should be after parse_header which poplulate pdu_fcall.
 595          */
 596         trace_9p_protocol_dump(c, req->rc);
 597         if (err) {
 598                 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 599                 return err;
 600         }
 601
 602         if (type != P9_RERROR && type != P9_RLERROR)
 603                 return 0;
 604
 605         if (!p9_is_proto_dotl(c)) {
 606                 /* Error is reported in string format */
 607                 int len;
 608                 /* 7 = header size for RERROR; */
 609                 int inline_len = in_hdrlen - 7;
 610
 611                 len =  req->rc->size - req->rc->offset;
 612                 if (len > (P9_ZC_HDR_SZ - 7)) {
 613                         err = -EFAULT;
 614                         goto out_err;
 615                 }
 616
 617                 ename = &req->rc->sdata[req->rc->offset];
 618                 if (len > inline_len) {
 619                         /* We have error in external buffer */
 620                         if (!copy_from_iter_full(ename + inline_len,
 621                                              len - inline_len, uidata)) {
 622                                 err = -EFAULT;
 623                                 goto out_err;
 624                         }
 625                 }
 626                 ename = NULL;
 627                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 628                                   &ename, &ecode);
 629                 if (err)
 630                         goto out_err;
 631
 632                 if (p9_is_proto_dotu(c) && ecode < 512)
 633                         err = -ecode;
 634
 635                 if (!err) {
 636                         err = p9_errstr2errno(ename, strlen(ename));
 637
 638                         p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 639                                  -ecode, ename);
 640                 }
 641                 kfree(ename);
 642         } else {
 643                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 644                 err = -ecode;
 645
 646                 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 647         }
 648         return err;
 649
 650 out_err:
 651         p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 652         return err;
 653 }
 654
 655 static struct p9_req_t *
 656 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
 657
 658 /**
 659  * p9_client_flush - flush (cancel) a request
 660  * @c: client state
 661  * @oldreq: request to cancel
 662  *
 663  * This sents a flush for a particular request and links
 664  * the flush request to the original request.  The current
 665  * code only supports a single flush request although the protocol
 666  * allows for multiple flush requests to be sent for a single request.
 667  *
 668  */
 669
 670 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 671 {
 672         struct p9_req_t *req;
 673         int16_t oldtag;
 674         int err;
 675
 676         err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
 677         if (err)
 678                 return err;
 679
 680         p9_debug(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
 681
 682         req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
 683         if (IS_ERR(req))
 684                 return PTR_ERR(req);
 685
 686         /*
 687          * if we haven't received a response for oldreq,
 688          * remove it from the list
 689          */
 690         if (oldreq->status == REQ_STATUS_SENT)
 691                 if (c->trans_mod->cancelled)
 692                         c->trans_mod->cancelled(c, oldreq);
 693
 694         p9_free_req(c, req);
 695         return 0;
 696 }
 697
 698 static struct p9_req_t *p9_client_prepare_req(struct p9_client *c,
 699                                               int8_t type, int req_size,
 700                                               const char *fmt, va_list ap)
 701 {
 702         int tag, err;
 703         struct p9_req_t *req;
 704
 705         p9_debug(P9_DEBUG_MUX, "client %p op %d\n", c, type);
 706
 707         /* we allow for any status other than disconnected */
 708         if (c->status == Disconnected)
 709                 return ERR_PTR(-EIO);
 710
 711         /* if status is begin_disconnected we allow only clunk request */
 712         if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
 713                 return ERR_PTR(-EIO);
 714
 715         tag = P9_NOTAG;
 716         if (type != P9_TVERSION) {
 717                 tag = p9_idpool_get(c->tagpool);
 718                 if (tag < 0)
 719                         return ERR_PTR(-ENOMEM);
 720         }
 721
 722         req = p9_tag_alloc(c, tag, req_size);
 723         if (IS_ERR(req))
 724                 return req;
 725
 726         /* marshall the data */
 727         p9pdu_prepare(req->tc, tag, type);
 728         err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
 729         if (err)
 730                 goto reterr;
 731         p9pdu_finalize(c, req->tc);
 732         trace_9p_client_req(c, type, tag);
 733         return req;
 734 reterr:
 735         p9_free_req(c, req);
 736         return ERR_PTR(err);
 737 }
 738
 739 /**
 740  * p9_client_rpc - issue a request and wait for a response
 741  * @c: client session
 742  * @type: type of request
 743  * @fmt: protocol format string (see protocol.c)
 744  *
 745  * Returns request structure (which client must free using p9_free_req)
 746  */
 747
 748 static struct p9_req_t *
 749 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 750 {
 751         va_list ap;
 752         int sigpending, err;
 753         unsigned long flags;
 754         struct p9_req_t *req;
 755
 756         va_start(ap, fmt);
 757         req = p9_client_prepare_req(c, type, c->msize, fmt, ap);
 758         va_end(ap);
 759         if (IS_ERR(req))
 760                 return req;
 761
 762         if (signal_pending(current)) {
 763                 sigpending = 1;
 764                 clear_thread_flag(TIF_SIGPENDING);
 765         } else
 766                 sigpending = 0;
 767
 768         err = c->trans_mod->request(c, req);
 769         if (err < 0) {
 770                 if (err != -ERESTARTSYS && err != -EFAULT)
 771                         c->status = Disconnected;
 772                 goto recalc_sigpending;
 773         }
 774 again:
 775         /* Wait for the response */
 776         err = wait_event_killable(*req->wq, req->status >= REQ_STATUS_RCVD);
 777
 778         /*
 779          * Make sure our req is coherent with regard to updates in other
 780          * threads - echoes to wmb() in the callback
 781          */
 782         smp_rmb();
 783
 784         if ((err == -ERESTARTSYS) && (c->status == Connected)
 785                                   && (type == P9_TFLUSH)) {
 786                 sigpending = 1;
 787                 clear_thread_flag(TIF_SIGPENDING);
 788                 goto again;
 789         }
 790
 791         if (req->status == REQ_STATUS_ERROR) {
 792                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 793                 err = req->t_err;
 794         }
 795         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 796                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 797                 sigpending = 1;
 798                 clear_thread_flag(TIF_SIGPENDING);
 799
 800                 if (c->trans_mod->cancel(c, req))
 801                         p9_client_flush(c, req);
 802
 803                 /* if we received the response anyway, don't signal error */
 804                 if (req->status == REQ_STATUS_RCVD)
 805                         err = 0;
 806         }
 807 recalc_sigpending:
 808         if (sigpending) {
 809                 spin_lock_irqsave(&current->sighand->siglock, flags);
 810                 recalc_sigpending();
 811                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 812         }
 813         if (err < 0)
 814                 goto reterr;
 815
 816         err = p9_check_errors(c, req);
 817         trace_9p_client_res(c, type, req->rc->tag, err);
 818         if (!err)
 819                 return req;
 820 reterr:
 821         p9_free_req(c, req);
 822         return ERR_PTR(safe_errno(err));
 823 }
 824
 825 /**
 826  * p9_client_zc_rpc - issue a request and wait for a response
 827  * @c: client session
 828  * @type: type of request
 829  * @uidata: destination for zero copy read
 830  * @uodata: source for zero copy write
 831  * @inlen: read buffer size
 832  * @olen: write buffer size
 833  * @hdrlen: reader header size, This is the size of response protocol data
 834  * @fmt: protocol format string (see protocol.c)
 835  *
 836  * Returns request structure (which client must free using p9_free_req)
 837  */
 838 static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
 839                                          struct iov_iter *uidata,
 840                                          struct iov_iter *uodata,
 841                                          int inlen, int olen, int in_hdrlen,
 842                                          const char *fmt, ...)
 843 {
 844         va_list ap;
 845         int sigpending, err;
 846         unsigned long flags;
 847         struct p9_req_t *req;
 848
 849         va_start(ap, fmt);
 850         /*
 851          * We allocate a inline protocol data of only 4k bytes.
 852          * The actual content is passed in zero-copy fashion.
 853          */
 854         req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, fmt, ap);
 855         va_end(ap);
 856         if (IS_ERR(req))
 857                 return req;
 858
 859         if (signal_pending(current)) {
 860                 sigpending = 1;
 861                 clear_thread_flag(TIF_SIGPENDING);
 862         } else
 863                 sigpending = 0;
 864
 865         err = c->trans_mod->zc_request(c, req, uidata, uodata,
 866                                        inlen, olen, in_hdrlen);
 867         if (err < 0) {
 868                 if (err == -EIO)
 869                         c->status = Disconnected;
 870                 if (err != -ERESTARTSYS)
 871                         goto recalc_sigpending;
 872         }
 873         if (req->status == REQ_STATUS_ERROR) {
 874                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 875                 err = req->t_err;
 876         }
 877         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 878                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 879                 sigpending = 1;
 880                 clear_thread_flag(TIF_SIGPENDING);
 881
 882                 if (c->trans_mod->cancel(c, req))
 883                         p9_client_flush(c, req);
 884
 885                 /* if we received the response anyway, don't signal error */
 886                 if (req->status == REQ_STATUS_RCVD)
 887                         err = 0;
 888         }
 889 recalc_sigpending:
 890         if (sigpending) {
 891                 spin_lock_irqsave(&current->sighand->siglock, flags);
 892                 recalc_sigpending();
 893                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 894         }
 895         if (err < 0)
 896                 goto reterr;
 897
 898         err = p9_check_zc_errors(c, req, uidata, in_hdrlen);
 899         trace_9p_client_res(c, type, req->rc->tag, err);
 900         if (!err)
 901                 return req;
 902 reterr:
 903         p9_free_req(c, req);
 904         return ERR_PTR(safe_errno(err));
 905 }
 906
 907 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 908 {
 909         int ret;
 910         struct p9_fid *fid;
 911         unsigned long flags;
 912
 913         p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt);
 914         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
 915         if (!fid)
 916                 return ERR_PTR(-ENOMEM);
 917
 918         ret = p9_idpool_get(clnt->fidpool);
 919         if (ret < 0) {
 920                 ret = -ENOSPC;
 921                 goto error;
 922         }
 923         fid->fid = ret;
 924
 925         memset(&fid->qid, 0, sizeof(struct p9_qid));
 926         fid->mode = -1;
 927         fid->uid = current_fsuid();
 928         fid->clnt = clnt;
 929         fid->rdir = NULL;
 930         spin_lock_irqsave(&clnt->lock, flags);
 931         list_add(&fid->flist, &clnt->fidlist);
 932         spin_unlock_irqrestore(&clnt->lock, flags);
 933
 934         return fid;
 935
 936 error:
 937         kfree(fid);
 938         return ERR_PTR(ret);
 939 }
 940
 941 static void p9_fid_destroy(struct p9_fid *fid)
 942 {
 943         struct p9_client *clnt;
 944         unsigned long flags;
 945
 946         p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
 947         clnt = fid->clnt;
 948         p9_idpool_put(fid->fid, clnt->fidpool);
 949         spin_lock_irqsave(&clnt->lock, flags);
 950         list_del(&fid->flist);
 951         spin_unlock_irqrestore(&clnt->lock, flags);
 952         kfree(fid->rdir);
 953         kfree(fid);
 954 }
 955
 956 static int p9_client_version(struct p9_client *c)
 957 {
 958         int err = 0;
 959         struct p9_req_t *req;
 960         char *version;
 961         int msize;
 962
 963         p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
 964                  c->msize, c->proto_version);
 965
 966         switch (c->proto_version) {
 967         case p9_proto_2000L:
 968                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 969                                         c->msize, "9P2000.L");
 970                 break;
 971         case p9_proto_2000u:
 972                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 973                                         c->msize, "9P2000.u");
 974                 break;
 975         case p9_proto_legacy:
 976                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 977                                         c->msize, "9P2000");
 978                 break;
 979         default:
 980                 return -EINVAL;
 981         }
 982
 983         if (IS_ERR(req))
 984                 return PTR_ERR(req);
 985
 986         err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
 987         if (err) {
 988                 p9_debug(P9_DEBUG_9P, "version error %d\n", err);
 989                 trace_9p_protocol_dump(c, req->rc);
 990                 goto error;
 991         }
 992
 993         p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
 994         if (!strncmp(version, "9P2000.L", 8))
 995                 c->proto_version = p9_proto_2000L;
 996         else if (!strncmp(version, "9P2000.u", 8))
 997                 c->proto_version = p9_proto_2000u;
 998         else if (!strncmp(version, "9P2000", 6))
 999                 c->proto_version = p9_proto_legacy;
1000         else {
1001                 err = -EREMOTEIO;
1002                 goto error;
1003         }
1004
1005         if (msize < c->msize)
1006                 c->msize = msize;
1007
1008 error:
1009         kfree(version);
1010         p9_free_req(c, req);
1011
1012         return err;
1013 }
1014
1015 struct p9_client *p9_client_create(const char *dev_name, char *options)
1016 {
1017         int err;
1018         struct p9_client *clnt;
1019         char *client_id;
1020
1021         err = 0;
1022         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
1023         if (!clnt)
1024                 return ERR_PTR(-ENOMEM);
1025
1026         clnt->trans_mod = NULL;
1027         clnt->trans = NULL;
1028
1029         client_id = utsname()->nodename;
1030         memcpy(clnt->name, client_id, strlen(client_id) + 1);
1031
1032         spin_lock_init(&clnt->lock);
1033         INIT_LIST_HEAD(&clnt->fidlist);
1034
1035         err = p9_tag_init(clnt);
1036         if (err < 0)
1037                 goto free_client;
1038
1039         err = parse_opts(options, clnt);
1040         if (err < 0)
1041                 goto destroy_tagpool;
1042
1043         if (!clnt->trans_mod)
1044                 clnt->trans_mod = v9fs_get_default_trans();
1045
1046         if (clnt->trans_mod == NULL) {
1047                 err = -EPROTONOSUPPORT;
1048                 p9_debug(P9_DEBUG_ERROR,
1049                          "No transport defined or default transport\n");
1050                 goto destroy_tagpool;
1051         }
1052
1053         clnt->fidpool = p9_idpool_create();
1054         if (IS_ERR(clnt->fidpool)) {
1055                 err = PTR_ERR(clnt->fidpool);
1056                 goto put_trans;
1057         }
1058
1059         p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1060                  clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1061
1062         err = clnt->trans_mod->create(clnt, dev_name, options);
1063         if (err)
1064                 goto destroy_fidpool;
1065
1066         if (clnt->msize > clnt->trans_mod->maxsize)
1067                 clnt->msize = clnt->trans_mod->maxsize;
1068
1069         err = p9_client_version(clnt);
1070         if (err)
1071                 goto close_trans;
1072
1073         return clnt;
1074
1075 close_trans:
1076         clnt->trans_mod->close(clnt);
1077 destroy_fidpool:
1078         p9_idpool_destroy(clnt->fidpool);
1079 put_trans:
1080         v9fs_put_trans(clnt->trans_mod);
1081 destroy_tagpool:
1082         p9_idpool_destroy(clnt->tagpool);
1083 free_client:
1084         kfree(clnt);
1085         return ERR_PTR(err);
1086 }
1087 EXPORT_SYMBOL(p9_client_create);
1088
1089 void p9_client_destroy(struct p9_client *clnt)
1090 {
1091         struct p9_fid *fid, *fidptr;
1092
1093         p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
1094
1095         if (clnt->trans_mod)
1096                 clnt->trans_mod->close(clnt);
1097
1098         v9fs_put_trans(clnt->trans_mod);
1099
1100         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
1101                 pr_info("Found fid %d not clunked\n", fid->fid);
1102                 p9_fid_destroy(fid);
1103         }
1104
1105         if (clnt->fidpool)
1106                 p9_idpool_destroy(clnt->fidpool);
1107
1108         p9_tag_cleanup(clnt);
1109
1110         kfree(clnt);
1111 }
1112 EXPORT_SYMBOL(p9_client_destroy);
1113
1114 void p9_client_disconnect(struct p9_client *clnt)
1115 {
1116         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1117         clnt->status = Disconnected;
1118 }
1119 EXPORT_SYMBOL(p9_client_disconnect);
1120
1121 void p9_client_begin_disconnect(struct p9_client *clnt)
1122 {
1123         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1124         clnt->status = BeginDisconnect;
1125 }
1126 EXPORT_SYMBOL(p9_client_begin_disconnect);
1127
1128 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1129         const char *uname, kuid_t n_uname, const char *aname)
1130 {
1131         int err = 0;
1132         struct p9_req_t *req;
1133         struct p9_fid *fid;
1134         struct p9_qid qid;
1135
1136
1137         p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1138                  afid ? afid->fid : -1, uname, aname);
1139         fid = p9_fid_create(clnt);
1140         if (IS_ERR(fid)) {
1141                 err = PTR_ERR(fid);
1142                 fid = NULL;
1143                 goto error;
1144         }
1145         fid->uid = n_uname;
1146
1147         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?u", fid->fid,
1148                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1149         if (IS_ERR(req)) {
1150                 err = PTR_ERR(req);
1151                 goto error;
1152         }
1153
1154         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
1155         if (err) {
1156                 trace_9p_protocol_dump(clnt, req->rc);
1157                 p9_free_req(clnt, req);
1158                 goto error;
1159         }
1160
1161         p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1162                  qid.type, (unsigned long long)qid.path, qid.version);
1163
1164         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1165
1166         p9_free_req(clnt, req);
1167         return fid;
1168
1169 error:
1170         if (fid)
1171                 p9_fid_destroy(fid);
1172         return ERR_PTR(err);
1173 }
1174 EXPORT_SYMBOL(p9_client_attach);
1175
1176 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1177                 const unsigned char * const *wnames, int clone)
1178 {
1179         int err;
1180         struct p9_client *clnt;
1181         struct p9_fid *fid;
1182         struct p9_qid *wqids;
1183         struct p9_req_t *req;
1184         uint16_t nwqids, count;
1185
1186         err = 0;
1187         wqids = NULL;
1188         clnt = oldfid->clnt;
1189         if (clone) {
1190                 fid = p9_fid_create(clnt);
1191                 if (IS_ERR(fid)) {
1192                         err = PTR_ERR(fid);
1193                         fid = NULL;
1194                         goto error;
1195                 }
1196
1197                 fid->uid = oldfid->uid;
1198         } else
1199                 fid = oldfid;
1200
1201
1202         p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1203                  oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1204
1205         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1206                                                                 nwname, wnames);
1207         if (IS_ERR(req)) {
1208                 err = PTR_ERR(req);
1209                 goto error;
1210         }
1211
1212         err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1213         if (err) {
1214                 trace_9p_protocol_dump(clnt, req->rc);
1215                 p9_free_req(clnt, req);
1216                 goto clunk_fid;
1217         }
1218         p9_free_req(clnt, req);
1219
1220         p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1221
1222         if (nwqids != nwname) {
1223                 err = -ENOENT;
1224                 goto clunk_fid;
1225         }
1226
1227         for (count = 0; count < nwqids; count++)
1228                 p9_debug(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
1229                         count, wqids[count].type,
1230                         (unsigned long long)wqids[count].path,
1231                         wqids[count].version);
1232
1233         if (nwname)
1234                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1235         else
1236                 fid->qid = oldfid->qid;
1237
1238         kfree(wqids);
1239         return fid;
1240
1241 clunk_fid:
1242         kfree(wqids);
1243         p9_client_clunk(fid);
1244         fid = NULL;
1245
1246 error:
1247         if (fid && (fid != oldfid))
1248                 p9_fid_destroy(fid);
1249
1250         return ERR_PTR(err);
1251 }
1252 EXPORT_SYMBOL(p9_client_walk);
1253
1254 int p9_client_open(struct p9_fid *fid, int mode)
1255 {
1256         int err;
1257         struct p9_client *clnt;
1258         struct p9_req_t *req;
1259         struct p9_qid qid;
1260         int iounit;
1261
1262         clnt = fid->clnt;
1263         p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1264                 p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1265         err = 0;
1266
1267         if (fid->mode != -1)
1268                 return -EINVAL;
1269
1270         if (p9_is_proto_dotl(clnt))
1271                 req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1272         else
1273                 req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1274         if (IS_ERR(req)) {
1275                 err = PTR_ERR(req);
1276                 goto error;
1277         }
1278
1279         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1280         if (err) {
1281                 trace_9p_protocol_dump(clnt, req->rc);
1282                 goto free_and_error;
1283         }
1284
1285         p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1286                 p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1287                 (unsigned long long)qid.path, qid.version, iounit);
1288
1289         fid->mode = mode;
1290         fid->iounit = iounit;
1291
1292 free_and_error:
1293         p9_free_req(clnt, req);
1294 error:
1295         return err;
1296 }
1297 EXPORT_SYMBOL(p9_client_open);
1298
1299 int p9_client_create_dotl(struct p9_fid *ofid, const char *name, u32 flags, u32 mode,
1300                 kgid_t gid, struct p9_qid *qid)
1301 {
1302         int err = 0;
1303         struct p9_client *clnt;
1304         struct p9_req_t *req;
1305         int iounit;
1306
1307         p9_debug(P9_DEBUG_9P,
1308                         ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1309                         ofid->fid, name, flags, mode,
1310                         from_kgid(&init_user_ns, gid));
1311         clnt = ofid->clnt;
1312
1313         if (ofid->mode != -1)
1314                 return -EINVAL;
1315
1316         req = p9_client_rpc(clnt, P9_TLCREATE, "dsddg", ofid->fid, name, flags,
1317                         mode, gid);
1318         if (IS_ERR(req)) {
1319                 err = PTR_ERR(req);
1320                 goto error;
1321         }
1322
1323         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1324         if (err) {
1325                 trace_9p_protocol_dump(clnt, req->rc);
1326                 goto free_and_error;
1327         }
1328
1329         p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1330                         qid->type,
1331                         (unsigned long long)qid->path,
1332                         qid->version, iounit);
1333
1334         ofid->mode = mode;
1335         ofid->iounit = iounit;
1336
1337 free_and_error:
1338         p9_free_req(clnt, req);
1339 error:
1340         return err;
1341 }
1342 EXPORT_SYMBOL(p9_client_create_dotl);
1343
1344 int p9_client_fcreate(struct p9_fid *fid, const char *name, u32 perm, int mode,
1345                      char *extension)
1346 {
1347         int err;
1348         struct p9_client *clnt;
1349         struct p9_req_t *req;
1350         struct p9_qid qid;
1351         int iounit;
1352
1353         p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1354                                                 fid->fid, name, perm, mode);
1355         err = 0;
1356         clnt = fid->clnt;
1357
1358         if (fid->mode != -1)
1359                 return -EINVAL;
1360
1361         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1362                                 mode, extension);
1363         if (IS_ERR(req)) {
1364                 err = PTR_ERR(req);
1365                 goto error;
1366         }
1367
1368         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1369         if (err) {
1370                 trace_9p_protocol_dump(clnt, req->rc);
1371                 goto free_and_error;
1372         }
1373
1374         p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1375                                 qid.type,
1376                                 (unsigned long long)qid.path,
1377                                 qid.version, iounit);
1378
1379         fid->mode = mode;
1380         fid->iounit = iounit;
1381
1382 free_and_error:
1383         p9_free_req(clnt, req);
1384 error:
1385         return err;
1386 }
1387 EXPORT_SYMBOL(p9_client_fcreate);
1388
1389 int p9_client_symlink(struct p9_fid *dfid, const char *name,
1390                 const char *symtgt, kgid_t gid, struct p9_qid *qid)
1391 {
1392         int err = 0;
1393         struct p9_client *clnt;
1394         struct p9_req_t *req;
1395
1396         p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1397                         dfid->fid, name, symtgt);
1398         clnt = dfid->clnt;
1399
1400         req = p9_client_rpc(clnt, P9_TSYMLINK, "dssg", dfid->fid, name, symtgt,
1401                         gid);
1402         if (IS_ERR(req)) {
1403                 err = PTR_ERR(req);
1404                 goto error;
1405         }
1406
1407         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1408         if (err) {
1409                 trace_9p_protocol_dump(clnt, req->rc);
1410                 goto free_and_error;
1411         }
1412
1413         p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1414                         qid->type, (unsigned long long)qid->path, qid->version);
1415
1416 free_and_error:
1417         p9_free_req(clnt, req);
1418 error:
1419         return err;
1420 }
1421 EXPORT_SYMBOL(p9_client_symlink);
1422
1423 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, const char *newname)
1424 {
1425         struct p9_client *clnt;
1426         struct p9_req_t *req;
1427
1428         p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1429                         dfid->fid, oldfid->fid, newname);
1430         clnt = dfid->clnt;
1431         req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1432                         newname);
1433         if (IS_ERR(req))
1434                 return PTR_ERR(req);
1435
1436         p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
1437         p9_free_req(clnt, req);
1438         return 0;
1439 }
1440 EXPORT_SYMBOL(p9_client_link);
1441
1442 int p9_client_fsync(struct p9_fid *fid, int datasync)
1443 {
1444         int err;
1445         struct p9_client *clnt;
1446         struct p9_req_t *req;
1447
1448         p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1449                         fid->fid, datasync);
1450         err = 0;
1451         clnt = fid->clnt;
1452
1453         req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1454         if (IS_ERR(req)) {
1455                 err = PTR_ERR(req);
1456                 goto error;
1457         }
1458
1459         p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1460
1461         p9_free_req(clnt, req);
1462
1463 error:
1464         return err;
1465 }
1466 EXPORT_SYMBOL(p9_client_fsync);
1467
1468 int p9_client_clunk(struct p9_fid *fid)
1469 {
1470         int err;
1471         struct p9_client *clnt;
1472         struct p9_req_t *req;
1473         int retries = 0;
1474
1475         if (!fid) {
1476                 pr_warn("%s (%d): Trying to clunk with NULL fid\n",
1477                         __func__, task_pid_nr(current));
1478                 dump_stack();
1479                 return 0;
1480         }
1481
1482 again:
1483         p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n", fid->fid,
1484                                                                 retries);
1485         err = 0;
1486         clnt = fid->clnt;
1487
1488         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1489         if (IS_ERR(req)) {
1490                 err = PTR_ERR(req);
1491                 goto error;
1492         }
1493
1494         p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1495
1496         p9_free_req(clnt, req);
1497 error:
1498         /*
1499          * Fid is not valid even after a failed clunk
1500          * If interrupted, retry once then give up and
1501          * leak fid until umount.
1502          */
1503         if (err == -ERESTARTSYS) {
1504                 if (retries++ == 0)
1505                         goto again;
1506         } else
1507                 p9_fid_destroy(fid);
1508         return err;
1509 }
1510 EXPORT_SYMBOL(p9_client_clunk);
1511
1512 int p9_client_remove(struct p9_fid *fid)
1513 {
1514         int err;
1515         struct p9_client *clnt;
1516         struct p9_req_t *req;
1517
1518         p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1519         err = 0;
1520         clnt = fid->clnt;
1521
1522         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1523         if (IS_ERR(req)) {
1524                 err = PTR_ERR(req);
1525                 goto error;
1526         }
1527
1528         p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1529
1530         p9_free_req(clnt, req);
1531 error:
1532         if (err == -ERESTARTSYS)
1533                 p9_client_clunk(fid);
1534         else
1535                 p9_fid_destroy(fid);
1536         return err;
1537 }
1538 EXPORT_SYMBOL(p9_client_remove);
1539
1540 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1541 {
1542         int err = 0;
1543         struct p9_req_t *req;
1544         struct p9_client *clnt;
1545
1546         p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1547                    dfid->fid, name, flags);
1548
1549         clnt = dfid->clnt;
1550         req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1551         if (IS_ERR(req)) {
1552                 err = PTR_ERR(req);
1553                 goto error;
1554         }
1555         p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1556
1557         p9_free_req(clnt, req);
1558 error:
1559         return err;
1560 }
1561 EXPORT_SYMBOL(p9_client_unlinkat);
1562
1563 int
1564 p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err)
1565 {
1566         struct p9_client *clnt = fid->clnt;
1567         struct p9_req_t *req;
1568         int total = 0;
1569         *err = 0;
1570
1571         p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
1572                    fid->fid, (unsigned long long) offset, (int)iov_iter_count(to));
1573
1574         while (iov_iter_count(to)) {
1575                 int count = iov_iter_count(to);
1576                 int rsize, non_zc = 0;
1577                 char *dataptr;
1578
1579                 rsize = fid->iounit;
1580                 if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1581                         rsize = clnt->msize - P9_IOHDRSZ;
1582
1583                 if (count < rsize)
1584                         rsize = count;
1585
1586                 /* Don't bother zerocopy for small IO (< 1024) */
1587                 if (clnt->trans_mod->zc_request && rsize > 1024) {
1588                         /*
1589                          * response header len is 11
1590                          * PDU Header(7) + IO Size (4)
1591                          */
1592                         req = p9_client_zc_rpc(clnt, P9_TREAD, to, NULL, rsize,
1593                                                0, 11, "dqd", fid->fid,
1594                                                offset, rsize);
1595                 } else {
1596                         non_zc = 1;
1597                         req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1598                                             rsize);
1599                 }
1600                 if (IS_ERR(req)) {
1601                         *err = PTR_ERR(req);
1602                         break;
1603                 }
1604
1605                 *err = p9pdu_readf(req->rc, clnt->proto_version,
1606                                    "D", &count, &dataptr);
1607                 if (*err) {
1608                         trace_9p_protocol_dump(clnt, req->rc);
1609                         p9_free_req(clnt, req);
1610                         break;
1611                 }
1612                 if (rsize < count) {
1613                         pr_err("bogus RREAD count (%d > %d)\n", count, rsize);
1614                         count = rsize;
1615                 }
1616
1617                 p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1618                 if (!count) {
1619                         p9_free_req(clnt, req);
1620                         break;
1621                 }
1622
1623                 if (non_zc) {
1624                         int n = copy_to_iter(dataptr, count, to);
1625                         total += n;
1626                         offset += n;
1627                         if (n != count) {
1628                                 *err = -EFAULT;
1629                                 p9_free_req(clnt, req);
1630                                 break;
1631                         }
1632                 } else {
1633                         iov_iter_advance(to, count);
1634                         total += count;
1635                         offset += count;
1636                 }
1637                 p9_free_req(clnt, req);
1638         }
1639         return total;
1640 }
1641 EXPORT_SYMBOL(p9_client_read);
1642
1643 int
1644 p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err)
1645 {
1646         struct p9_client *clnt = fid->clnt;
1647         struct p9_req_t *req;
1648         int total = 0;
1649         *err = 0;
1650
1651         p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %zd\n",
1652                                 fid->fid, (unsigned long long) offset,
1653                                 iov_iter_count(from));
1654
1655         while (iov_iter_count(from)) {
1656                 int count = iov_iter_count(from);
1657                 int rsize = fid->iounit;
1658                 if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1659                         rsize = clnt->msize - P9_IOHDRSZ;
1660
1661                 if (count < rsize)
1662                         rsize = count;
1663
1664                 /* Don't bother zerocopy for small IO (< 1024) */
1665                 if (clnt->trans_mod->zc_request && rsize > 1024) {
1666                         req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, from, 0,
1667                                                rsize, P9_ZC_HDR_SZ, "dqd",
1668                                                fid->fid, offset, rsize);
1669                 } else {
1670                         req = p9_client_rpc(clnt, P9_TWRITE, "dqV", fid->fid,
1671                                                     offset, rsize, from);
1672                 }
1673                 if (IS_ERR(req)) {
1674                         *err = PTR_ERR(req);
1675                         break;
1676                 }
1677
1678                 *err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1679                 if (*err) {
1680                         trace_9p_protocol_dump(clnt, req->rc);
1681                         p9_free_req(clnt, req);
1682                         break;
1683                 }
1684                 if (rsize < count) {
1685                         pr_err("bogus RWRITE count (%d > %d)\n", count, rsize);
1686                         count = rsize;
1687                 }
1688
1689                 p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1690
1691                 p9_free_req(clnt, req);
1692                 iov_iter_advance(from, count);
1693                 total += count;
1694                 offset += count;
1695         }
1696         return total;
1697 }
1698 EXPORT_SYMBOL(p9_client_write);
1699
1700 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1701 {
1702         int err;
1703         struct p9_client *clnt;
1704         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1705         struct p9_req_t *req;
1706         u16 ignored;
1707
1708         p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1709
1710         if (!ret)
1711                 return ERR_PTR(-ENOMEM);
1712
1713         err = 0;
1714         clnt = fid->clnt;
1715
1716         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1717         if (IS_ERR(req)) {
1718                 err = PTR_ERR(req);
1719                 goto error;
1720         }
1721
1722         err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1723         if (err) {
1724                 trace_9p_protocol_dump(clnt, req->rc);
1725                 p9_free_req(clnt, req);
1726                 goto error;
1727         }
1728
1729         p9_debug(P9_DEBUG_9P,
1730                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1731                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1732                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1733                 "<<<    uid=%d gid=%d n_muid=%d\n",
1734                 ret->size, ret->type, ret->dev, ret->qid.type,
1735                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1736                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1737                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1738                 from_kuid(&init_user_ns, ret->n_uid),
1739                 from_kgid(&init_user_ns, ret->n_gid),
1740                 from_kuid(&init_user_ns, ret->n_muid));
1741
1742         p9_free_req(clnt, req);
1743         return ret;
1744
1745 error:
1746         kfree(ret);
1747         return ERR_PTR(err);
1748 }
1749 EXPORT_SYMBOL(p9_client_stat);
1750
1751 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1752                                                         u64 request_mask)
1753 {
1754         int err;
1755         struct p9_client *clnt;
1756         struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1757                                                                 GFP_KERNEL);
1758         struct p9_req_t *req;
1759
1760         p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1761                                                         fid->fid, request_mask);
1762
1763         if (!ret)
1764                 return ERR_PTR(-ENOMEM);
1765
1766         err = 0;
1767         clnt = fid->clnt;
1768
1769         req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1770         if (IS_ERR(req)) {
1771                 err = PTR_ERR(req);
1772                 goto error;
1773         }
1774
1775         err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1776         if (err) {
1777                 trace_9p_protocol_dump(clnt, req->rc);
1778                 p9_free_req(clnt, req);
1779                 goto error;
1780         }
1781
1782         p9_debug(P9_DEBUG_9P,
1783                 "<<< RGETATTR st_result_mask=%lld\n"
1784                 "<<< qid=%x.%llx.%x\n"
1785                 "<<< st_mode=%8.8x st_nlink=%llu\n"
1786                 "<<< st_uid=%d st_gid=%d\n"
1787                 "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1788                 "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1789                 "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1790                 "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1791                 "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1792                 "<<< st_gen=%lld st_data_version=%lld",
1793                 ret->st_result_mask, ret->qid.type, ret->qid.path,
1794                 ret->qid.version, ret->st_mode, ret->st_nlink,
1795                 from_kuid(&init_user_ns, ret->st_uid),
1796                 from_kgid(&init_user_ns, ret->st_gid),
1797                 ret->st_rdev, ret->st_size, ret->st_blksize,
1798                 ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1799                 ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1800                 ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1801                 ret->st_gen, ret->st_data_version);
1802
1803         p9_free_req(clnt, req);
1804         return ret;
1805
1806 error:
1807         kfree(ret);
1808         return ERR_PTR(err);
1809 }
1810 EXPORT_SYMBOL(p9_client_getattr_dotl);
1811
1812 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1813 {
1814         int ret;
1815
1816         /* NOTE: size shouldn't include its own length */
1817         /* size[2] type[2] dev[4] qid[13] */
1818         /* mode[4] atime[4] mtime[4] length[8]*/
1819         /* name[s] uid[s] gid[s] muid[s] */
1820         ret = 2+4+13+4+4+4+8+2+2+2+2;
1821
1822         if (wst->name)
1823                 ret += strlen(wst->name);
1824         if (wst->uid)
1825                 ret += strlen(wst->uid);
1826         if (wst->gid)
1827                 ret += strlen(wst->gid);
1828         if (wst->muid)
1829                 ret += strlen(wst->muid);
1830
1831         if ((proto_version == p9_proto_2000u) ||
1832                 (proto_version == p9_proto_2000L)) {
1833                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1834                 if (wst->extension)
1835                         ret += strlen(wst->extension);
1836         }
1837
1838         return ret;
1839 }
1840
1841 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1842 {
1843         int err;
1844         struct p9_req_t *req;
1845         struct p9_client *clnt;
1846
1847         err = 0;
1848         clnt = fid->clnt;
1849         wst->size = p9_client_statsize(wst, clnt->proto_version);
1850         p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1851         p9_debug(P9_DEBUG_9P,
1852                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1853                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1854                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1855                 "     uid=%d gid=%d n_muid=%d\n",
1856                 wst->size, wst->type, wst->dev, wst->qid.type,
1857                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1858                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1859                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1860                 from_kuid(&init_user_ns, wst->n_uid),
1861                 from_kgid(&init_user_ns, wst->n_gid),
1862                 from_kuid(&init_user_ns, wst->n_muid));
1863
1864         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1865         if (IS_ERR(req)) {
1866                 err = PTR_ERR(req);
1867                 goto error;
1868         }
1869
1870         p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1871
1872         p9_free_req(clnt, req);
1873 error:
1874         return err;
1875 }
1876 EXPORT_SYMBOL(p9_client_wstat);
1877
1878 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1879 {
1880         int err;
1881         struct p9_req_t *req;
1882         struct p9_client *clnt;
1883
1884         err = 0;
1885         clnt = fid->clnt;
1886         p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1887         p9_debug(P9_DEBUG_9P,
1888                 "    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1889                 "    atime_sec=%lld atime_nsec=%lld\n"
1890                 "    mtime_sec=%lld mtime_nsec=%lld\n",
1891                 p9attr->valid, p9attr->mode,
1892                 from_kuid(&init_user_ns, p9attr->uid),
1893                 from_kgid(&init_user_ns, p9attr->gid),
1894                 p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1895                 p9attr->mtime_sec, p9attr->mtime_nsec);
1896
1897         req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1898
1899         if (IS_ERR(req)) {
1900                 err = PTR_ERR(req);
1901                 goto error;
1902         }
1903         p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1904         p9_free_req(clnt, req);
1905 error:
1906         return err;
1907 }
1908 EXPORT_SYMBOL(p9_client_setattr);
1909
1910 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1911 {
1912         int err;
1913         struct p9_req_t *req;
1914         struct p9_client *clnt;
1915
1916         err = 0;
1917         clnt = fid->clnt;
1918
1919         p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1920
1921         req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1922         if (IS_ERR(req)) {
1923                 err = PTR_ERR(req);
1924                 goto error;
1925         }
1926
1927         err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1928                 &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1929                 &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1930         if (err) {
1931                 trace_9p_protocol_dump(clnt, req->rc);
1932                 p9_free_req(clnt, req);
1933                 goto error;
1934         }
1935
1936         p9_debug(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1937                 "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1938                 "fsid %llu namelen %ld\n",
1939                 fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1940                 sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1941                 sb->fsid, (long int)sb->namelen);
1942
1943         p9_free_req(clnt, req);
1944 error:
1945         return err;
1946 }
1947 EXPORT_SYMBOL(p9_client_statfs);
1948
1949 int p9_client_rename(struct p9_fid *fid,
1950                      struct p9_fid *newdirfid, const char *name)
1951 {
1952         int err;
1953         struct p9_req_t *req;
1954         struct p9_client *clnt;
1955
1956         err = 0;
1957         clnt = fid->clnt;
1958
1959         p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1960                         fid->fid, newdirfid->fid, name);
1961
1962         req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1963                         newdirfid->fid, name);
1964         if (IS_ERR(req)) {
1965                 err = PTR_ERR(req);
1966                 goto error;
1967         }
1968
1969         p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1970
1971         p9_free_req(clnt, req);
1972 error:
1973         return err;
1974 }
1975 EXPORT_SYMBOL(p9_client_rename);
1976
1977 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1978                        struct p9_fid *newdirfid, const char *new_name)
1979 {
1980         int err;
1981         struct p9_req_t *req;
1982         struct p9_client *clnt;
1983
1984         err = 0;
1985         clnt = olddirfid->clnt;
1986
1987         p9_debug(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1988                    " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1989                    newdirfid->fid, new_name);
1990
1991         req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1992                             old_name, newdirfid->fid, new_name);
1993         if (IS_ERR(req)) {
1994                 err = PTR_ERR(req);
1995                 goto error;
1996         }
1997
1998         p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
1999                    newdirfid->fid, new_name);
2000
2001         p9_free_req(clnt, req);
2002 error:
2003         return err;
2004 }
2005 EXPORT_SYMBOL(p9_client_renameat);
2006
2007 /*
2008  * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
2009  */
2010 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
2011                                 const char *attr_name, u64 *attr_size)
2012 {
2013         int err;
2014         struct p9_req_t *req;
2015         struct p9_client *clnt;
2016         struct p9_fid *attr_fid;
2017
2018         err = 0;
2019         clnt = file_fid->clnt;
2020         attr_fid = p9_fid_create(clnt);
2021         if (IS_ERR(attr_fid)) {
2022                 err = PTR_ERR(attr_fid);
2023                 attr_fid = NULL;
2024                 goto error;
2025         }
2026         p9_debug(P9_DEBUG_9P,
2027                 ">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
2028                 file_fid->fid, attr_fid->fid, attr_name);
2029
2030         req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
2031                         file_fid->fid, attr_fid->fid, attr_name);
2032         if (IS_ERR(req)) {
2033                 err = PTR_ERR(req);
2034                 goto error;
2035         }
2036         err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
2037         if (err) {
2038                 trace_9p_protocol_dump(clnt, req->rc);
2039                 p9_free_req(clnt, req);
2040                 goto clunk_fid;
2041         }
2042         p9_free_req(clnt, req);
2043         p9_debug(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
2044                 attr_fid->fid, *attr_size);
2045         return attr_fid;
2046 clunk_fid:
2047         p9_client_clunk(attr_fid);
2048         attr_fid = NULL;
2049 error:
2050         if (attr_fid && (attr_fid != file_fid))
2051                 p9_fid_destroy(attr_fid);
2052
2053         return ERR_PTR(err);
2054 }
2055 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
2056
2057 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
2058                         u64 attr_size, int flags)
2059 {
2060         int err;
2061         struct p9_req_t *req;
2062         struct p9_client *clnt;
2063
2064         p9_debug(P9_DEBUG_9P,
2065                 ">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
2066                 fid->fid, name, (long long)attr_size, flags);
2067         err = 0;
2068         clnt = fid->clnt;
2069         req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2070                         fid->fid, name, attr_size, flags);
2071         if (IS_ERR(req)) {
2072                 err = PTR_ERR(req);
2073                 goto error;
2074         }
2075         p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2076         p9_free_req(clnt, req);
2077 error:
2078         return err;
2079 }
2080 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2081
2082 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2083 {
2084         int err, rsize, non_zc = 0;
2085         struct p9_client *clnt;
2086         struct p9_req_t *req;
2087         char *dataptr;
2088         struct kvec kv = {.iov_base = data, .iov_len = count};
2089         struct iov_iter to;
2090
2091         iov_iter_kvec(&to, READ | ITER_KVEC, &kv, 1, count);
2092
2093         p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2094                                 fid->fid, (unsigned long long) offset, count);
2095
2096         err = 0;
2097         clnt = fid->clnt;
2098
2099         rsize = fid->iounit;
2100         if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2101                 rsize = clnt->msize - P9_READDIRHDRSZ;
2102
2103         if (count < rsize)
2104                 rsize = count;
2105
2106         /* Don't bother zerocopy for small IO (< 1024) */
2107         if (clnt->trans_mod->zc_request && rsize > 1024) {
2108                 /*
2109                  * response header len is 11
2110                  * PDU Header(7) + IO Size (4)
2111                  */
2112                 req = p9_client_zc_rpc(clnt, P9_TREADDIR, &to, NULL, rsize, 0,
2113                                        11, "dqd", fid->fid, offset, rsize);
2114         } else {
2115                 non_zc = 1;
2116                 req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2117                                     offset, rsize);
2118         }
2119         if (IS_ERR(req)) {
2120                 err = PTR_ERR(req);
2121                 goto error;
2122         }
2123
2124         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2125         if (err) {
2126                 trace_9p_protocol_dump(clnt, req->rc);
2127                 goto free_and_error;
2128         }
2129         if (rsize < count) {
2130                 pr_err("bogus RREADDIR count (%d > %d)\n", count, rsize);
2131                 count = rsize;
2132         }
2133
2134         p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2135
2136         if (non_zc)
2137                 memmove(data, dataptr, count);
2138
2139         p9_free_req(clnt, req);
2140         return count;
2141
2142 free_and_error:
2143         p9_free_req(clnt, req);
2144 error:
2145         return err;
2146 }
2147 EXPORT_SYMBOL(p9_client_readdir);
2148
2149 int p9_client_mknod_dotl(struct p9_fid *fid, const char *name, int mode,
2150                         dev_t rdev, kgid_t gid, struct p9_qid *qid)
2151 {
2152         int err;
2153         struct p9_client *clnt;
2154         struct p9_req_t *req;
2155
2156         err = 0;
2157         clnt = fid->clnt;
2158         p9_debug(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2159                 "minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2160         req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddg", fid->fid, name, mode,
2161                 MAJOR(rdev), MINOR(rdev), gid);
2162         if (IS_ERR(req))
2163                 return PTR_ERR(req);
2164
2165         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2166         if (err) {
2167                 trace_9p_protocol_dump(clnt, req->rc);
2168                 goto error;
2169         }
2170         p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2171                                 (unsigned long long)qid->path, qid->version);
2172
2173 error:
2174         p9_free_req(clnt, req);
2175         return err;
2176
2177 }
2178 EXPORT_SYMBOL(p9_client_mknod_dotl);
2179
2180 int p9_client_mkdir_dotl(struct p9_fid *fid, const char *name, int mode,
2181                                 kgid_t gid, struct p9_qid *qid)
2182 {
2183         int err;
2184         struct p9_client *clnt;
2185         struct p9_req_t *req;
2186
2187         err = 0;
2188         clnt = fid->clnt;
2189         p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2190                  fid->fid, name, mode, from_kgid(&init_user_ns, gid));
2191         req = p9_client_rpc(clnt, P9_TMKDIR, "dsdg", fid->fid, name, mode,
2192                 gid);
2193         if (IS_ERR(req))
2194                 return PTR_ERR(req);
2195
2196         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2197         if (err) {
2198                 trace_9p_protocol_dump(clnt, req->rc);
2199                 goto error;
2200         }
2201         p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2202                                 (unsigned long long)qid->path, qid->version);
2203
2204 error:
2205         p9_free_req(clnt, req);
2206         return err;
2207
2208 }
2209 EXPORT_SYMBOL(p9_client_mkdir_dotl);
2210
2211 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2212 {
2213         int err;
2214         struct p9_client *clnt;
2215         struct p9_req_t *req;
2216
2217         err = 0;
2218         clnt = fid->clnt;
2219         p9_debug(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2220                         "start %lld length %lld proc_id %d client_id %s\n",
2221                         fid->fid, flock->type, flock->flags, flock->start,
2222                         flock->length, flock->proc_id, flock->client_id);
2223
2224         req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2225                                 flock->flags, flock->start, flock->length,
2226                                         flock->proc_id, flock->client_id);
2227
2228         if (IS_ERR(req))
2229                 return PTR_ERR(req);
2230
2231         err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2232         if (err) {
2233                 trace_9p_protocol_dump(clnt, req->rc);
2234                 goto error;
2235         }
2236         p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2237 error:
2238         p9_free_req(clnt, req);
2239         return err;
2240
2241 }
2242 EXPORT_SYMBOL(p9_client_lock_dotl);
2243
2244 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2245 {
2246         int err;
2247         struct p9_client *clnt;
2248         struct p9_req_t *req;
2249
2250         err = 0;
2251         clnt = fid->clnt;
2252         p9_debug(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
2253                 "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2254                 glock->start, glock->length, glock->proc_id, glock->client_id);
2255
2256         req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
2257                 glock->start, glock->length, glock->proc_id, glock->client_id);
2258
2259         if (IS_ERR(req))
2260                 return PTR_ERR(req);
2261
2262         err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2263                         &glock->start, &glock->length, &glock->proc_id,
2264                         &glock->client_id);
2265         if (err) {
2266                 trace_9p_protocol_dump(clnt, req->rc);
2267                 goto error;
2268         }
2269         p9_debug(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2270                 "proc_id %d client_id %s\n", glock->type, glock->start,
2271                 glock->length, glock->proc_id, glock->client_id);
2272 error:
2273         p9_free_req(clnt, req);
2274         return err;
2275 }
2276 EXPORT_SYMBOL(p9_client_getlock_dotl);
2277
2278 int p9_client_readlink(struct p9_fid *fid, char **target)
2279 {
2280         int err;
2281         struct p9_client *clnt;
2282         struct p9_req_t *req;
2283
2284         err = 0;
2285         clnt = fid->clnt;
2286         p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2287
2288         req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2289         if (IS_ERR(req))
2290                 return PTR_ERR(req);
2291
2292         err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2293         if (err) {
2294                 trace_9p_protocol_dump(clnt, req->rc);
2295                 goto error;
2296         }
2297         p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2298 error:
2299         p9_free_req(clnt, req);
2300         return err;
2301 }
2302 EXPORT_SYMBOL(p9_client_readlink);