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                         if (option < 4096) {
 185                                 p9_debug(P9_DEBUG_ERROR,
 186                                          "msize should be at least 4k\n");
 187                                 ret = -EINVAL;
 188                                 continue;
 189                         }
 190                         clnt->msize = option;
 191                         break;
 192                 case Opt_trans:
 193                         s = match_strdup(&args[0]);
 194                         if (!s) {
 195                                 ret = -ENOMEM;
 196                                 p9_debug(P9_DEBUG_ERROR,
 197                                          "problem allocating copy of trans arg\n");
 198                                 goto free_and_return;
 199                          }
 200                         clnt->trans_mod = v9fs_get_trans_by_name(s);
 201                         if (clnt->trans_mod == NULL) {
 202                                 pr_info("Could not find request transport: %s\n",
 203                                         s);
 204                                 ret = -EINVAL;
 205                                 kfree(s);
 206                                 goto free_and_return;
 207                         }
 208                         kfree(s);
 209                         break;
 210                 case Opt_legacy:
 211                         clnt->proto_version = p9_proto_legacy;
 212                         break;
 213                 case Opt_version:
 214                         s = match_strdup(&args[0]);
 215                         if (!s) {
 216                                 ret = -ENOMEM;
 217                                 p9_debug(P9_DEBUG_ERROR,
 218                                          "problem allocating copy of version arg\n");
 219                                 goto free_and_return;
 220                         }
 221                         ret = get_protocol_version(s);
 222                         if (ret == -EINVAL) {
 223                                 kfree(s);
 224                                 goto free_and_return;
 225                         }
 226                         kfree(s);
 227                         clnt->proto_version = ret;
 228                         break;
 229                 default:
 230                         continue;
 231                 }
 232         }
 233
 234 free_and_return:
 235         kfree(tmp_options);
 236         return ret;
 237 }
 238
 239 static struct p9_fcall *p9_fcall_alloc(int alloc_msize)
 240 {
 241         struct p9_fcall *fc;
 242         fc = kmalloc(sizeof(struct p9_fcall) + alloc_msize, GFP_NOFS);
 243         if (!fc)
 244                 return NULL;
 245         fc->capacity = alloc_msize;
 246         fc->sdata = (char *) fc + sizeof(struct p9_fcall);
 247         return fc;
 248 }
 249
 250 /**
 251  * p9_tag_alloc - lookup/allocate a request by tag
 252  * @c: client session to lookup tag within
 253  * @tag: numeric id for transaction
 254  *
 255  * this is a simple array lookup, but will grow the
 256  * request_slots as necessary to accommodate transaction
 257  * ids which did not previously have a slot.
 258  *
 259  * this code relies on the client spinlock to manage locks, its
 260  * possible we should switch to something else, but I'd rather
 261  * stick with something low-overhead for the common case.
 262  *
 263  */
 264
 265 static struct p9_req_t *
 266 p9_tag_alloc(struct p9_client *c, u16 tag, unsigned int max_size)
 267 {
 268         unsigned long flags;
 269         int row, col;
 270         struct p9_req_t *req;
 271         int alloc_msize = min(c->msize, max_size);
 272
 273         /* This looks up the original request by tag so we know which
 274          * buffer to read the data into */
 275         tag++;
 276
 277         if (tag >= c->max_tag) {
 278                 spin_lock_irqsave(&c->lock, flags);
 279                 /* check again since original check was outside of lock */
 280                 while (tag >= c->max_tag) {
 281                         row = (tag / P9_ROW_MAXTAG);
 282                         c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
 283                                         sizeof(struct p9_req_t), GFP_ATOMIC);
 284
 285                         if (!c->reqs[row]) {
 286                                 pr_err("Couldn't grow tag array\n");
 287                                 spin_unlock_irqrestore(&c->lock, flags);
 288                                 return ERR_PTR(-ENOMEM);
 289                         }
 290                         for (col = 0; col < P9_ROW_MAXTAG; col++) {
 291                                 c->reqs[row][col].status = REQ_STATUS_IDLE;
 292                                 c->reqs[row][col].tc = NULL;
 293                         }
 294                         c->max_tag += P9_ROW_MAXTAG;
 295                 }
 296                 spin_unlock_irqrestore(&c->lock, flags);
 297         }
 298         row = tag / P9_ROW_MAXTAG;
 299         col = tag % P9_ROW_MAXTAG;
 300
 301         req = &c->reqs[row][col];
 302         if (!req->wq) {
 303                 req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_NOFS);
 304                 if (!req->wq)
 305                         goto grow_failed;
 306                 init_waitqueue_head(req->wq);
 307         }
 308
 309         if (!req->tc)
 310                 req->tc = p9_fcall_alloc(alloc_msize);
 311         if (!req->rc)
 312                 req->rc = p9_fcall_alloc(alloc_msize);
 313         if (!req->tc || !req->rc)
 314                 goto grow_failed;
 315
 316         p9pdu_reset(req->tc);
 317         p9pdu_reset(req->rc);
 318
 319         req->tc->tag = tag-1;
 320         req->status = REQ_STATUS_ALLOC;
 321
 322         return req;
 323
 324 grow_failed:
 325         pr_err("Couldn't grow tag array\n");
 326         kfree(req->tc);
 327         kfree(req->rc);
 328         kfree(req->wq);
 329         req->tc = req->rc = NULL;
 330         req->wq = NULL;
 331         return ERR_PTR(-ENOMEM);
 332 }
 333
 334 /**
 335  * p9_tag_lookup - lookup a request by tag
 336  * @c: client session to lookup tag within
 337  * @tag: numeric id for transaction
 338  *
 339  */
 340
 341 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
 342 {
 343         int row, col;
 344
 345         /* This looks up the original request by tag so we know which
 346          * buffer to read the data into */
 347         tag++;
 348
 349         if(tag >= c->max_tag)
 350                 return NULL;
 351
 352         row = tag / P9_ROW_MAXTAG;
 353         col = tag % P9_ROW_MAXTAG;
 354
 355         return &c->reqs[row][col];
 356 }
 357 EXPORT_SYMBOL(p9_tag_lookup);
 358
 359 /**
 360  * p9_tag_init - setup tags structure and contents
 361  * @c:  v9fs client struct
 362  *
 363  * This initializes the tags structure for each client instance.
 364  *
 365  */
 366
 367 static int p9_tag_init(struct p9_client *c)
 368 {
 369         int err = 0;
 370
 371         c->tagpool = p9_idpool_create();
 372         if (IS_ERR(c->tagpool)) {
 373                 err = PTR_ERR(c->tagpool);
 374                 goto error;
 375         }
 376         err = p9_idpool_get(c->tagpool); /* reserve tag 0 */
 377         if (err < 0) {
 378                 p9_idpool_destroy(c->tagpool);
 379                 goto error;
 380         }
 381         c->max_tag = 0;
 382 error:
 383         return err;
 384 }
 385
 386 /**
 387  * p9_tag_cleanup - cleans up tags structure and reclaims resources
 388  * @c:  v9fs client struct
 389  *
 390  * This frees resources associated with the tags structure
 391  *
 392  */
 393 static void p9_tag_cleanup(struct p9_client *c)
 394 {
 395         int row, col;
 396
 397         /* check to insure all requests are idle */
 398         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 399                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 400                         if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
 401                                 p9_debug(P9_DEBUG_MUX,
 402                                          "Attempting to cleanup non-free tag %d,%d\n",
 403                                          row, col);
 404                                 /* TODO: delay execution of cleanup */
 405                                 return;
 406                         }
 407                 }
 408         }
 409
 410         if (c->tagpool) {
 411                 p9_idpool_put(0, c->tagpool); /* free reserved tag 0 */
 412                 p9_idpool_destroy(c->tagpool);
 413         }
 414
 415         /* free requests associated with tags */
 416         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 417                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 418                         kfree(c->reqs[row][col].wq);
 419                         kfree(c->reqs[row][col].tc);
 420                         kfree(c->reqs[row][col].rc);
 421                 }
 422                 kfree(c->reqs[row]);
 423         }
 424         c->max_tag = 0;
 425 }
 426
 427 /**
 428  * p9_free_req - free a request and clean-up as necessary
 429  * c: client state
 430  * r: request to release
 431  *
 432  */
 433
 434 static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
 435 {
 436         int tag = r->tc->tag;
 437         p9_debug(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
 438
 439         r->status = REQ_STATUS_IDLE;
 440         if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
 441                 p9_idpool_put(tag, c->tagpool);
 442 }
 443
 444 /**
 445  * p9_client_cb - call back from transport to client
 446  * c: client state
 447  * req: request received
 448  *
 449  */
 450 void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status)
 451 {
 452         p9_debug(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
 453
 454         /*
 455          * This barrier is needed to make sure any change made to req before
 456          * the other thread wakes up will indeed be seen by the waiting side.
 457          */
 458         smp_wmb();
 459         req->status = status;
 460
 461         wake_up(req->wq);
 462         p9_debug(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
 463 }
 464 EXPORT_SYMBOL(p9_client_cb);
 465
 466 /**
 467  * p9_parse_header - parse header arguments out of a packet
 468  * @pdu: packet to parse
 469  * @size: size of packet
 470  * @type: type of request
 471  * @tag: tag of packet
 472  * @rewind: set if we need to rewind offset afterwards
 473  */
 474
 475 int
 476 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
 477                                                                 int rewind)
 478 {
 479         int8_t r_type;
 480         int16_t r_tag;
 481         int32_t r_size;
 482         int offset = pdu->offset;
 483         int err;
 484
 485         pdu->offset = 0;
 486         if (pdu->size == 0)
 487                 pdu->size = 7;
 488
 489         err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
 490         if (err)
 491                 goto rewind_and_exit;
 492
 493         pdu->size = r_size;
 494         pdu->id = r_type;
 495         pdu->tag = r_tag;
 496
 497         p9_debug(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n",
 498                  pdu->size, pdu->id, pdu->tag);
 499
 500         if (type)
 501                 *type = r_type;
 502         if (tag)
 503                 *tag = r_tag;
 504         if (size)
 505                 *size = r_size;
 506
 507
 508 rewind_and_exit:
 509         if (rewind)
 510                 pdu->offset = offset;
 511         return err;
 512 }
 513 EXPORT_SYMBOL(p9_parse_header);
 514
 515 /**
 516  * p9_check_errors - check 9p packet for error return and process it
 517  * @c: current client instance
 518  * @req: request to parse and check for error conditions
 519  *
 520  * returns error code if one is discovered, otherwise returns 0
 521  *
 522  * this will have to be more complicated if we have multiple
 523  * error packet types
 524  */
 525
 526 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 527 {
 528         int8_t type;
 529         int err;
 530         int ecode;
 531
 532         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 533         /*
 534          * dump the response from server
 535          * This should be after check errors which poplulate pdu_fcall.
 536          */
 537         trace_9p_protocol_dump(c, req->rc);
 538         if (err) {
 539                 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 540                 return err;
 541         }
 542         if (type != P9_RERROR && type != P9_RLERROR)
 543                 return 0;
 544
 545         if (!p9_is_proto_dotl(c)) {
 546                 char *ename;
 547                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 548                                   &ename, &ecode);
 549                 if (err)
 550                         goto out_err;
 551
 552                 if (p9_is_proto_dotu(c) && ecode < 512)
 553                         err = -ecode;
 554
 555                 if (!err) {
 556                         err = p9_errstr2errno(ename, strlen(ename));
 557
 558                         p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 559                                  -ecode, ename);
 560                 }
 561                 kfree(ename);
 562         } else {
 563                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 564                 err = -ecode;
 565
 566                 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 567         }
 568
 569         return err;
 570
 571 out_err:
 572         p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 573
 574         return err;
 575 }
 576
 577 /**
 578  * p9_check_zc_errors - check 9p packet for error return and process it
 579  * @c: current client instance
 580  * @req: request to parse and check for error conditions
 581  * @in_hdrlen: Size of response protocol buffer.
 582  *
 583  * returns error code if one is discovered, otherwise returns 0
 584  *
 585  * this will have to be more complicated if we have multiple
 586  * error packet types
 587  */
 588
 589 static int p9_check_zc_errors(struct p9_client *c, struct p9_req_t *req,
 590                               struct iov_iter *uidata, int in_hdrlen)
 591 {
 592         int err;
 593         int ecode;
 594         int8_t type;
 595         char *ename = NULL;
 596
 597         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 598         /*
 599          * dump the response from server
 600          * This should be after parse_header which poplulate pdu_fcall.
 601          */
 602         trace_9p_protocol_dump(c, req->rc);
 603         if (err) {
 604                 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 605                 return err;
 606         }
 607
 608         if (type != P9_RERROR && type != P9_RLERROR)
 609                 return 0;
 610
 611         if (!p9_is_proto_dotl(c)) {
 612                 /* Error is reported in string format */
 613                 int len;
 614                 /* 7 = header size for RERROR; */
 615                 int inline_len = in_hdrlen - 7;
 616
 617                 len =  req->rc->size - req->rc->offset;
 618                 if (len > (P9_ZC_HDR_SZ - 7)) {
 619                         err = -EFAULT;
 620                         goto out_err;
 621                 }
 622
 623                 ename = &req->rc->sdata[req->rc->offset];
 624                 if (len > inline_len) {
 625                         /* We have error in external buffer */
 626                         if (!copy_from_iter_full(ename + inline_len,
 627                                              len - inline_len, uidata)) {
 628                                 err = -EFAULT;
 629                                 goto out_err;
 630                         }
 631                 }
 632                 ename = NULL;
 633                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 634                                   &ename, &ecode);
 635                 if (err)
 636                         goto out_err;
 637
 638                 if (p9_is_proto_dotu(c) && ecode < 512)
 639                         err = -ecode;
 640
 641                 if (!err) {
 642                         err = p9_errstr2errno(ename, strlen(ename));
 643
 644                         p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 645                                  -ecode, ename);
 646                 }
 647                 kfree(ename);
 648         } else {
 649                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 650                 err = -ecode;
 651
 652                 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 653         }
 654         return err;
 655
 656 out_err:
 657         p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 658         return err;
 659 }
 660
 661 static struct p9_req_t *
 662 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
 663
 664 /**
 665  * p9_client_flush - flush (cancel) a request
 666  * @c: client state
 667  * @oldreq: request to cancel
 668  *
 669  * This sents a flush for a particular request and links
 670  * the flush request to the original request.  The current
 671  * code only supports a single flush request although the protocol
 672  * allows for multiple flush requests to be sent for a single request.
 673  *
 674  */
 675
 676 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 677 {
 678         struct p9_req_t *req;
 679         int16_t oldtag;
 680         int err;
 681
 682         err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
 683         if (err)
 684                 return err;
 685
 686         p9_debug(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
 687
 688         req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
 689         if (IS_ERR(req))
 690                 return PTR_ERR(req);
 691
 692         /*
 693          * if we haven't received a response for oldreq,
 694          * remove it from the list
 695          */
 696         if (oldreq->status == REQ_STATUS_SENT)
 697                 if (c->trans_mod->cancelled)
 698                         c->trans_mod->cancelled(c, oldreq);
 699
 700         p9_free_req(c, req);
 701         return 0;
 702 }
 703
 704 static struct p9_req_t *p9_client_prepare_req(struct p9_client *c,
 705                                               int8_t type, int req_size,
 706                                               const char *fmt, va_list ap)
 707 {
 708         int tag, err;
 709         struct p9_req_t *req;
 710
 711         p9_debug(P9_DEBUG_MUX, "client %p op %d\n", c, type);
 712
 713         /* we allow for any status other than disconnected */
 714         if (c->status == Disconnected)
 715                 return ERR_PTR(-EIO);
 716
 717         /* if status is begin_disconnected we allow only clunk request */
 718         if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
 719                 return ERR_PTR(-EIO);
 720
 721         tag = P9_NOTAG;
 722         if (type != P9_TVERSION) {
 723                 tag = p9_idpool_get(c->tagpool);
 724                 if (tag < 0)
 725                         return ERR_PTR(-ENOMEM);
 726         }
 727
 728         req = p9_tag_alloc(c, tag, req_size);
 729         if (IS_ERR(req))
 730                 return req;
 731
 732         /* marshall the data */
 733         p9pdu_prepare(req->tc, tag, type);
 734         err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
 735         if (err)
 736                 goto reterr;
 737         p9pdu_finalize(c, req->tc);
 738         trace_9p_client_req(c, type, tag);
 739         return req;
 740 reterr:
 741         p9_free_req(c, req);
 742         return ERR_PTR(err);
 743 }
 744
 745 /**
 746  * p9_client_rpc - issue a request and wait for a response
 747  * @c: client session
 748  * @type: type of request
 749  * @fmt: protocol format string (see protocol.c)
 750  *
 751  * Returns request structure (which client must free using p9_free_req)
 752  */
 753
 754 static struct p9_req_t *
 755 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 756 {
 757         va_list ap;
 758         int sigpending, err;
 759         unsigned long flags;
 760         struct p9_req_t *req;
 761
 762         va_start(ap, fmt);
 763         req = p9_client_prepare_req(c, type, c->msize, fmt, ap);
 764         va_end(ap);
 765         if (IS_ERR(req))
 766                 return req;
 767
 768         if (signal_pending(current)) {
 769                 sigpending = 1;
 770                 clear_thread_flag(TIF_SIGPENDING);
 771         } else
 772                 sigpending = 0;
 773
 774         err = c->trans_mod->request(c, req);
 775         if (err < 0) {
 776                 if (err != -ERESTARTSYS && err != -EFAULT)
 777                         c->status = Disconnected;
 778                 goto reterr;
 779         }
 780 again:
 781         /* Wait for the response */
 782         err = wait_event_killable(*req->wq, req->status >= REQ_STATUS_RCVD);
 783
 784         /*
 785          * Make sure our req is coherent with regard to updates in other
 786          * threads - echoes to wmb() in the callback
 787          */
 788         smp_rmb();
 789
 790         if ((err == -ERESTARTSYS) && (c->status == Connected)
 791                                   && (type == P9_TFLUSH)) {
 792                 sigpending = 1;
 793                 clear_thread_flag(TIF_SIGPENDING);
 794                 goto again;
 795         }
 796
 797         if (req->status == REQ_STATUS_ERROR) {
 798                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 799                 err = req->t_err;
 800         }
 801         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 802                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 803                 sigpending = 1;
 804                 clear_thread_flag(TIF_SIGPENDING);
 805
 806                 if (c->trans_mod->cancel(c, req))
 807                         p9_client_flush(c, req);
 808
 809                 /* if we received the response anyway, don't signal error */
 810                 if (req->status == REQ_STATUS_RCVD)
 811                         err = 0;
 812         }
 813         if (sigpending) {
 814                 spin_lock_irqsave(&current->sighand->siglock, flags);
 815                 recalc_sigpending();
 816                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 817         }
 818         if (err < 0)
 819                 goto reterr;
 820
 821         err = p9_check_errors(c, req);
 822         trace_9p_client_res(c, type, req->rc->tag, err);
 823         if (!err)
 824                 return req;
 825 reterr:
 826         p9_free_req(c, req);
 827         return ERR_PTR(safe_errno(err));
 828 }
 829
 830 /**
 831  * p9_client_zc_rpc - issue a request and wait for a response
 832  * @c: client session
 833  * @type: type of request
 834  * @uidata: destination for zero copy read
 835  * @uodata: source for zero copy write
 836  * @inlen: read buffer size
 837  * @olen: write buffer size
 838  * @hdrlen: reader header size, This is the size of response protocol data
 839  * @fmt: protocol format string (see protocol.c)
 840  *
 841  * Returns request structure (which client must free using p9_free_req)
 842  */
 843 static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
 844                                          struct iov_iter *uidata,
 845                                          struct iov_iter *uodata,
 846                                          int inlen, int olen, int in_hdrlen,
 847                                          const char *fmt, ...)
 848 {
 849         va_list ap;
 850         int sigpending, err;
 851         unsigned long flags;
 852         struct p9_req_t *req;
 853
 854         va_start(ap, fmt);
 855         /*
 856          * We allocate a inline protocol data of only 4k bytes.
 857          * The actual content is passed in zero-copy fashion.
 858          */
 859         req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, fmt, ap);
 860         va_end(ap);
 861         if (IS_ERR(req))
 862                 return req;
 863
 864         if (signal_pending(current)) {
 865                 sigpending = 1;
 866                 clear_thread_flag(TIF_SIGPENDING);
 867         } else
 868                 sigpending = 0;
 869
 870         err = c->trans_mod->zc_request(c, req, uidata, uodata,
 871                                        inlen, olen, in_hdrlen);
 872         if (err < 0) {
 873                 if (err == -EIO)
 874                         c->status = Disconnected;
 875                 if (err != -ERESTARTSYS)
 876                         goto reterr;
 877         }
 878         if (req->status == REQ_STATUS_ERROR) {
 879                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 880                 err = req->t_err;
 881         }
 882         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 883                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 884                 sigpending = 1;
 885                 clear_thread_flag(TIF_SIGPENDING);
 886
 887                 if (c->trans_mod->cancel(c, req))
 888                         p9_client_flush(c, req);
 889
 890                 /* if we received the response anyway, don't signal error */
 891                 if (req->status == REQ_STATUS_RCVD)
 892                         err = 0;
 893         }
 894         if (sigpending) {
 895                 spin_lock_irqsave(&current->sighand->siglock, flags);
 896                 recalc_sigpending();
 897                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 898         }
 899         if (err < 0)
 900                 goto reterr;
 901
 902         err = p9_check_zc_errors(c, req, uidata, in_hdrlen);
 903         trace_9p_client_res(c, type, req->rc->tag, err);
 904         if (!err)
 905                 return req;
 906 reterr:
 907         p9_free_req(c, req);
 908         return ERR_PTR(safe_errno(err));
 909 }
 910
 911 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 912 {
 913         int ret;
 914         struct p9_fid *fid;
 915         unsigned long flags;
 916
 917         p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt);
 918         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
 919         if (!fid)
 920                 return ERR_PTR(-ENOMEM);
 921
 922         ret = p9_idpool_get(clnt->fidpool);
 923         if (ret < 0) {
 924                 ret = -ENOSPC;
 925                 goto error;
 926         }
 927         fid->fid = ret;
 928
 929         memset(&fid->qid, 0, sizeof(struct p9_qid));
 930         fid->mode = -1;
 931         fid->uid = current_fsuid();
 932         fid->clnt = clnt;
 933         fid->rdir = NULL;
 934         spin_lock_irqsave(&clnt->lock, flags);
 935         list_add(&fid->flist, &clnt->fidlist);
 936         spin_unlock_irqrestore(&clnt->lock, flags);
 937
 938         return fid;
 939
 940 error:
 941         kfree(fid);
 942         return ERR_PTR(ret);
 943 }
 944
 945 static void p9_fid_destroy(struct p9_fid *fid)
 946 {
 947         struct p9_client *clnt;
 948         unsigned long flags;
 949
 950         p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
 951         clnt = fid->clnt;
 952         p9_idpool_put(fid->fid, clnt->fidpool);
 953         spin_lock_irqsave(&clnt->lock, flags);
 954         list_del(&fid->flist);
 955         spin_unlock_irqrestore(&clnt->lock, flags);
 956         kfree(fid->rdir);
 957         kfree(fid);
 958 }
 959
 960 static int p9_client_version(struct p9_client *c)
 961 {
 962         int err = 0;
 963         struct p9_req_t *req;
 964         char *version = NULL;
 965         int msize;
 966
 967         p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
 968                  c->msize, c->proto_version);
 969
 970         switch (c->proto_version) {
 971         case p9_proto_2000L:
 972                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 973                                         c->msize, "9P2000.L");
 974                 break;
 975         case p9_proto_2000u:
 976                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 977                                         c->msize, "9P2000.u");
 978                 break;
 979         case p9_proto_legacy:
 980                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 981                                         c->msize, "9P2000");
 982                 break;
 983         default:
 984                 return -EINVAL;
 985         }
 986
 987         if (IS_ERR(req))
 988                 return PTR_ERR(req);
 989
 990         err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
 991         if (err) {
 992                 p9_debug(P9_DEBUG_9P, "version error %d\n", err);
 993                 trace_9p_protocol_dump(c, req->rc);
 994                 goto error;
 995         }
 996
 997         p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
 998         if (!strncmp(version, "9P2000.L", 8))
 999                 c->proto_version = p9_proto_2000L;
1000         else if (!strncmp(version, "9P2000.u", 8))
1001                 c->proto_version = p9_proto_2000u;
1002         else if (!strncmp(version, "9P2000", 6))
1003                 c->proto_version = p9_proto_legacy;
1004         else {
1005                 p9_debug(P9_DEBUG_ERROR,
1006                          "server returned an unknown version: %s\n", version);
1007                 err = -EREMOTEIO;
1008                 goto error;
1009         }
1010
1011         if (msize < 4096) {
1012                 p9_debug(P9_DEBUG_ERROR,
1013                          "server returned a msize < 4096: %d\n", msize);
1014                 err = -EREMOTEIO;
1015                 goto error;
1016         }
1017         if (msize < c->msize)
1018                 c->msize = msize;
1019
1020 error:
1021         kfree(version);
1022         p9_free_req(c, req);
1023
1024         return err;
1025 }
1026
1027 struct p9_client *p9_client_create(const char *dev_name, char *options)
1028 {
1029         int err;
1030         struct p9_client *clnt;
1031         char *client_id;
1032
1033         err = 0;
1034         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
1035         if (!clnt)
1036                 return ERR_PTR(-ENOMEM);
1037
1038         clnt->trans_mod = NULL;
1039         clnt->trans = NULL;
1040
1041         client_id = utsname()->nodename;
1042         memcpy(clnt->name, client_id, strlen(client_id) + 1);
1043
1044         spin_lock_init(&clnt->lock);
1045         INIT_LIST_HEAD(&clnt->fidlist);
1046
1047         err = p9_tag_init(clnt);
1048         if (err < 0)
1049                 goto free_client;
1050
1051         err = parse_opts(options, clnt);
1052         if (err < 0)
1053                 goto destroy_tagpool;
1054
1055         if (!clnt->trans_mod)
1056                 clnt->trans_mod = v9fs_get_default_trans();
1057
1058         if (clnt->trans_mod == NULL) {
1059                 err = -EPROTONOSUPPORT;
1060                 p9_debug(P9_DEBUG_ERROR,
1061                          "No transport defined or default transport\n");
1062                 goto destroy_tagpool;
1063         }
1064
1065         clnt->fidpool = p9_idpool_create();
1066         if (IS_ERR(clnt->fidpool)) {
1067                 err = PTR_ERR(clnt->fidpool);
1068                 goto put_trans;
1069         }
1070
1071         p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1072                  clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1073
1074         err = clnt->trans_mod->create(clnt, dev_name, options);
1075         if (err)
1076                 goto destroy_fidpool;
1077
1078         if (clnt->msize > clnt->trans_mod->maxsize)
1079                 clnt->msize = clnt->trans_mod->maxsize;
1080
1081         if (clnt->msize < 4096) {
1082                 p9_debug(P9_DEBUG_ERROR,
1083                          "Please specify a msize of at least 4k\n");
1084                 err = -EINVAL;
1085                 goto close_trans;
1086         }
1087
1088         err = p9_client_version(clnt);
1089         if (err)
1090                 goto close_trans;
1091
1092         return clnt;
1093
1094 close_trans:
1095         clnt->trans_mod->close(clnt);
1096 destroy_fidpool:
1097         p9_idpool_destroy(clnt->fidpool);
1098 put_trans:
1099         v9fs_put_trans(clnt->trans_mod);
1100 destroy_tagpool:
1101         p9_idpool_destroy(clnt->tagpool);
1102 free_client:
1103         kfree(clnt);
1104         return ERR_PTR(err);
1105 }
1106 EXPORT_SYMBOL(p9_client_create);
1107
1108 void p9_client_destroy(struct p9_client *clnt)
1109 {
1110         struct p9_fid *fid, *fidptr;
1111
1112         p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
1113
1114         if (clnt->trans_mod)
1115                 clnt->trans_mod->close(clnt);
1116
1117         v9fs_put_trans(clnt->trans_mod);
1118
1119         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
1120                 pr_info("Found fid %d not clunked\n", fid->fid);
1121                 p9_fid_destroy(fid);
1122         }
1123
1124         if (clnt->fidpool)
1125                 p9_idpool_destroy(clnt->fidpool);
1126
1127         p9_tag_cleanup(clnt);
1128
1129         kfree(clnt);
1130 }
1131 EXPORT_SYMBOL(p9_client_destroy);
1132
1133 void p9_client_disconnect(struct p9_client *clnt)
1134 {
1135         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1136         clnt->status = Disconnected;
1137 }
1138 EXPORT_SYMBOL(p9_client_disconnect);
1139
1140 void p9_client_begin_disconnect(struct p9_client *clnt)
1141 {
1142         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1143         clnt->status = BeginDisconnect;
1144 }
1145 EXPORT_SYMBOL(p9_client_begin_disconnect);
1146
1147 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1148         const char *uname, kuid_t n_uname, const char *aname)
1149 {
1150         int err = 0;
1151         struct p9_req_t *req;
1152         struct p9_fid *fid;
1153         struct p9_qid qid;
1154
1155
1156         p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1157                  afid ? afid->fid : -1, uname, aname);
1158         fid = p9_fid_create(clnt);
1159         if (IS_ERR(fid)) {
1160                 err = PTR_ERR(fid);
1161                 fid = NULL;
1162                 goto error;
1163         }
1164         fid->uid = n_uname;
1165
1166         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?u", fid->fid,
1167                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1168         if (IS_ERR(req)) {
1169                 err = PTR_ERR(req);
1170                 goto error;
1171         }
1172
1173         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
1174         if (err) {
1175                 trace_9p_protocol_dump(clnt, req->rc);
1176                 p9_free_req(clnt, req);
1177                 goto error;
1178         }
1179
1180         p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1181                  qid.type, (unsigned long long)qid.path, qid.version);
1182
1183         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1184
1185         p9_free_req(clnt, req);
1186         return fid;
1187
1188 error:
1189         if (fid)
1190                 p9_fid_destroy(fid);
1191         return ERR_PTR(err);
1192 }
1193 EXPORT_SYMBOL(p9_client_attach);
1194
1195 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1196                 const unsigned char * const *wnames, int clone)
1197 {
1198         int err;
1199         struct p9_client *clnt;
1200         struct p9_fid *fid;
1201         struct p9_qid *wqids;
1202         struct p9_req_t *req;
1203         uint16_t nwqids, count;
1204
1205         err = 0;
1206         wqids = NULL;
1207         clnt = oldfid->clnt;
1208         if (clone) {
1209                 fid = p9_fid_create(clnt);
1210                 if (IS_ERR(fid)) {
1211                         err = PTR_ERR(fid);
1212                         fid = NULL;
1213                         goto error;
1214                 }
1215
1216                 fid->uid = oldfid->uid;
1217         } else
1218                 fid = oldfid;
1219
1220
1221         p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1222                  oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1223
1224         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1225                                                                 nwname, wnames);
1226         if (IS_ERR(req)) {
1227                 err = PTR_ERR(req);
1228                 goto error;
1229         }
1230
1231         err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1232         if (err) {
1233                 trace_9p_protocol_dump(clnt, req->rc);
1234                 p9_free_req(clnt, req);
1235                 goto clunk_fid;
1236         }
1237         p9_free_req(clnt, req);
1238
1239         p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1240
1241         if (nwqids != nwname) {
1242                 err = -ENOENT;
1243                 goto clunk_fid;
1244         }
1245
1246         for (count = 0; count < nwqids; count++)
1247                 p9_debug(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
1248                         count, wqids[count].type,
1249                         (unsigned long long)wqids[count].path,
1250                         wqids[count].version);
1251
1252         if (nwname)
1253                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1254         else
1255                 fid->qid = oldfid->qid;
1256
1257         kfree(wqids);
1258         return fid;
1259
1260 clunk_fid:
1261         kfree(wqids);
1262         p9_client_clunk(fid);
1263         fid = NULL;
1264
1265 error:
1266         if (fid && (fid != oldfid))
1267                 p9_fid_destroy(fid);
1268
1269         return ERR_PTR(err);
1270 }
1271 EXPORT_SYMBOL(p9_client_walk);
1272
1273 int p9_client_open(struct p9_fid *fid, int mode)
1274 {
1275         int err;
1276         struct p9_client *clnt;
1277         struct p9_req_t *req;
1278         struct p9_qid qid;
1279         int iounit;
1280
1281         clnt = fid->clnt;
1282         p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1283                 p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1284         err = 0;
1285
1286         if (fid->mode != -1)
1287                 return -EINVAL;
1288
1289         if (p9_is_proto_dotl(clnt))
1290                 req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1291         else
1292                 req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1293         if (IS_ERR(req)) {
1294                 err = PTR_ERR(req);
1295                 goto error;
1296         }
1297
1298         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1299         if (err) {
1300                 trace_9p_protocol_dump(clnt, req->rc);
1301                 goto free_and_error;
1302         }
1303
1304         p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1305                 p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1306                 (unsigned long long)qid.path, qid.version, iounit);
1307
1308         fid->mode = mode;
1309         fid->iounit = iounit;
1310
1311 free_and_error:
1312         p9_free_req(clnt, req);
1313 error:
1314         return err;
1315 }
1316 EXPORT_SYMBOL(p9_client_open);
1317
1318 int p9_client_create_dotl(struct p9_fid *ofid, const char *name, u32 flags, u32 mode,
1319                 kgid_t gid, struct p9_qid *qid)
1320 {
1321         int err = 0;
1322         struct p9_client *clnt;
1323         struct p9_req_t *req;
1324         int iounit;
1325
1326         p9_debug(P9_DEBUG_9P,
1327                         ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1328                         ofid->fid, name, flags, mode,
1329                         from_kgid(&init_user_ns, gid));
1330         clnt = ofid->clnt;
1331
1332         if (ofid->mode != -1)
1333                 return -EINVAL;
1334
1335         req = p9_client_rpc(clnt, P9_TLCREATE, "dsddg", ofid->fid, name, flags,
1336                         mode, gid);
1337         if (IS_ERR(req)) {
1338                 err = PTR_ERR(req);
1339                 goto error;
1340         }
1341
1342         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1343         if (err) {
1344                 trace_9p_protocol_dump(clnt, req->rc);
1345                 goto free_and_error;
1346         }
1347
1348         p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1349                         qid->type,
1350                         (unsigned long long)qid->path,
1351                         qid->version, iounit);
1352
1353         ofid->mode = mode;
1354         ofid->iounit = iounit;
1355
1356 free_and_error:
1357         p9_free_req(clnt, req);
1358 error:
1359         return err;
1360 }
1361 EXPORT_SYMBOL(p9_client_create_dotl);
1362
1363 int p9_client_fcreate(struct p9_fid *fid, const char *name, u32 perm, int mode,
1364                      char *extension)
1365 {
1366         int err;
1367         struct p9_client *clnt;
1368         struct p9_req_t *req;
1369         struct p9_qid qid;
1370         int iounit;
1371
1372         p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1373                                                 fid->fid, name, perm, mode);
1374         err = 0;
1375         clnt = fid->clnt;
1376
1377         if (fid->mode != -1)
1378                 return -EINVAL;
1379
1380         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1381                                 mode, extension);
1382         if (IS_ERR(req)) {
1383                 err = PTR_ERR(req);
1384                 goto error;
1385         }
1386
1387         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1388         if (err) {
1389                 trace_9p_protocol_dump(clnt, req->rc);
1390                 goto free_and_error;
1391         }
1392
1393         p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1394                                 qid.type,
1395                                 (unsigned long long)qid.path,
1396                                 qid.version, iounit);
1397
1398         fid->mode = mode;
1399         fid->iounit = iounit;
1400
1401 free_and_error:
1402         p9_free_req(clnt, req);
1403 error:
1404         return err;
1405 }
1406 EXPORT_SYMBOL(p9_client_fcreate);
1407
1408 int p9_client_symlink(struct p9_fid *dfid, const char *name,
1409                 const char *symtgt, kgid_t gid, struct p9_qid *qid)
1410 {
1411         int err = 0;
1412         struct p9_client *clnt;
1413         struct p9_req_t *req;
1414
1415         p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1416                         dfid->fid, name, symtgt);
1417         clnt = dfid->clnt;
1418
1419         req = p9_client_rpc(clnt, P9_TSYMLINK, "dssg", dfid->fid, name, symtgt,
1420                         gid);
1421         if (IS_ERR(req)) {
1422                 err = PTR_ERR(req);
1423                 goto error;
1424         }
1425
1426         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1427         if (err) {
1428                 trace_9p_protocol_dump(clnt, req->rc);
1429                 goto free_and_error;
1430         }
1431
1432         p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1433                         qid->type, (unsigned long long)qid->path, qid->version);
1434
1435 free_and_error:
1436         p9_free_req(clnt, req);
1437 error:
1438         return err;
1439 }
1440 EXPORT_SYMBOL(p9_client_symlink);
1441
1442 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, const char *newname)
1443 {
1444         struct p9_client *clnt;
1445         struct p9_req_t *req;
1446
1447         p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1448                         dfid->fid, oldfid->fid, newname);
1449         clnt = dfid->clnt;
1450         req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1451                         newname);
1452         if (IS_ERR(req))
1453                 return PTR_ERR(req);
1454
1455         p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
1456         p9_free_req(clnt, req);
1457         return 0;
1458 }
1459 EXPORT_SYMBOL(p9_client_link);
1460
1461 int p9_client_fsync(struct p9_fid *fid, int datasync)
1462 {
1463         int err;
1464         struct p9_client *clnt;
1465         struct p9_req_t *req;
1466
1467         p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1468                         fid->fid, datasync);
1469         err = 0;
1470         clnt = fid->clnt;
1471
1472         req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1473         if (IS_ERR(req)) {
1474                 err = PTR_ERR(req);
1475                 goto error;
1476         }
1477
1478         p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1479
1480         p9_free_req(clnt, req);
1481
1482 error:
1483         return err;
1484 }
1485 EXPORT_SYMBOL(p9_client_fsync);
1486
1487 int p9_client_clunk(struct p9_fid *fid)
1488 {
1489         int err;
1490         struct p9_client *clnt;
1491         struct p9_req_t *req;
1492         int retries = 0;
1493
1494         if (!fid) {
1495                 pr_warn("%s (%d): Trying to clunk with NULL fid\n",
1496                         __func__, task_pid_nr(current));
1497                 dump_stack();
1498                 return 0;
1499         }
1500
1501 again:
1502         p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n", fid->fid,
1503                                                                 retries);
1504         err = 0;
1505         clnt = fid->clnt;
1506
1507         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1508         if (IS_ERR(req)) {
1509                 err = PTR_ERR(req);
1510                 goto error;
1511         }
1512
1513         p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1514
1515         p9_free_req(clnt, req);
1516 error:
1517         /*
1518          * Fid is not valid even after a failed clunk
1519          * If interrupted, retry once then give up and
1520          * leak fid until umount.
1521          */
1522         if (err == -ERESTARTSYS) {
1523                 if (retries++ == 0)
1524                         goto again;
1525         } else
1526                 p9_fid_destroy(fid);
1527         return err;
1528 }
1529 EXPORT_SYMBOL(p9_client_clunk);
1530
1531 int p9_client_remove(struct p9_fid *fid)
1532 {
1533         int err;
1534         struct p9_client *clnt;
1535         struct p9_req_t *req;
1536
1537         p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1538         err = 0;
1539         clnt = fid->clnt;
1540
1541         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1542         if (IS_ERR(req)) {
1543                 err = PTR_ERR(req);
1544                 goto error;
1545         }
1546
1547         p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1548
1549         p9_free_req(clnt, req);
1550 error:
1551         if (err == -ERESTARTSYS)
1552                 p9_client_clunk(fid);
1553         else
1554                 p9_fid_destroy(fid);
1555         return err;
1556 }
1557 EXPORT_SYMBOL(p9_client_remove);
1558
1559 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1560 {
1561         int err = 0;
1562         struct p9_req_t *req;
1563         struct p9_client *clnt;
1564
1565         p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1566                    dfid->fid, name, flags);
1567
1568         clnt = dfid->clnt;
1569         req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1570         if (IS_ERR(req)) {
1571                 err = PTR_ERR(req);
1572                 goto error;
1573         }
1574         p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1575
1576         p9_free_req(clnt, req);
1577 error:
1578         return err;
1579 }
1580 EXPORT_SYMBOL(p9_client_unlinkat);
1581
1582 int
1583 p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err)
1584 {
1585         struct p9_client *clnt = fid->clnt;
1586         struct p9_req_t *req;
1587         int total = 0;
1588         *err = 0;
1589
1590         p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
1591                    fid->fid, (unsigned long long) offset, (int)iov_iter_count(to));
1592
1593         while (iov_iter_count(to)) {
1594                 int count = iov_iter_count(to);
1595                 int rsize, non_zc = 0;
1596                 char *dataptr;
1597
1598                 rsize = fid->iounit;
1599                 if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1600                         rsize = clnt->msize - P9_IOHDRSZ;
1601
1602                 if (count < rsize)
1603                         rsize = count;
1604
1605                 /* Don't bother zerocopy for small IO (< 1024) */
1606                 if (clnt->trans_mod->zc_request && rsize > 1024) {
1607                         /*
1608                          * response header len is 11
1609                          * PDU Header(7) + IO Size (4)
1610                          */
1611                         req = p9_client_zc_rpc(clnt, P9_TREAD, to, NULL, rsize,
1612                                                0, 11, "dqd", fid->fid,
1613                                                offset, rsize);
1614                 } else {
1615                         non_zc = 1;
1616                         req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1617                                             rsize);
1618                 }
1619                 if (IS_ERR(req)) {
1620                         *err = PTR_ERR(req);
1621                         break;
1622                 }
1623
1624                 *err = p9pdu_readf(req->rc, clnt->proto_version,
1625                                    "D", &count, &dataptr);
1626                 if (*err) {
1627                         trace_9p_protocol_dump(clnt, req->rc);
1628                         p9_free_req(clnt, req);
1629                         break;
1630                 }
1631                 if (rsize < count) {
1632                         pr_err("bogus RREAD count (%d > %d)\n", count, rsize);
1633                         count = rsize;
1634                 }
1635
1636                 p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1637                 if (!count) {
1638                         p9_free_req(clnt, req);
1639                         break;
1640                 }
1641
1642                 if (non_zc) {
1643                         int n = copy_to_iter(dataptr, count, to);
1644                         total += n;
1645                         offset += n;
1646                         if (n != count) {
1647                                 *err = -EFAULT;
1648                                 p9_free_req(clnt, req);
1649                                 break;
1650                         }
1651                 } else {
1652                         iov_iter_advance(to, count);
1653                         total += count;
1654                         offset += count;
1655                 }
1656                 p9_free_req(clnt, req);
1657         }
1658         return total;
1659 }
1660 EXPORT_SYMBOL(p9_client_read);
1661
1662 int
1663 p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err)
1664 {
1665         struct p9_client *clnt = fid->clnt;
1666         struct p9_req_t *req;
1667         int total = 0;
1668         *err = 0;
1669
1670         p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %zd\n",
1671                                 fid->fid, (unsigned long long) offset,
1672                                 iov_iter_count(from));
1673
1674         while (iov_iter_count(from)) {
1675                 int count = iov_iter_count(from);
1676                 int rsize = fid->iounit;
1677                 if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1678                         rsize = clnt->msize - P9_IOHDRSZ;
1679
1680                 if (count < rsize)
1681                         rsize = count;
1682
1683                 /* Don't bother zerocopy for small IO (< 1024) */
1684                 if (clnt->trans_mod->zc_request && rsize > 1024) {
1685                         req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, from, 0,
1686                                                rsize, P9_ZC_HDR_SZ, "dqd",
1687                                                fid->fid, offset, rsize);
1688                 } else {
1689                         req = p9_client_rpc(clnt, P9_TWRITE, "dqV", fid->fid,
1690                                                     offset, rsize, from);
1691                 }
1692                 if (IS_ERR(req)) {
1693                         *err = PTR_ERR(req);
1694                         break;
1695                 }
1696
1697                 *err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1698                 if (*err) {
1699                         trace_9p_protocol_dump(clnt, req->rc);
1700                         p9_free_req(clnt, req);
1701                         break;
1702                 }
1703                 if (rsize < count) {
1704                         pr_err("bogus RWRITE count (%d > %d)\n", count, rsize);
1705                         count = rsize;
1706                 }
1707
1708                 p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1709
1710                 p9_free_req(clnt, req);
1711                 iov_iter_advance(from, count);
1712                 total += count;
1713                 offset += count;
1714         }
1715         return total;
1716 }
1717 EXPORT_SYMBOL(p9_client_write);
1718
1719 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1720 {
1721         int err;
1722         struct p9_client *clnt;
1723         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1724         struct p9_req_t *req;
1725         u16 ignored;
1726
1727         p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1728
1729         if (!ret)
1730                 return ERR_PTR(-ENOMEM);
1731
1732         err = 0;
1733         clnt = fid->clnt;
1734
1735         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1736         if (IS_ERR(req)) {
1737                 err = PTR_ERR(req);
1738                 goto error;
1739         }
1740
1741         err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1742         if (err) {
1743                 trace_9p_protocol_dump(clnt, req->rc);
1744                 p9_free_req(clnt, req);
1745                 goto error;
1746         }
1747
1748         p9_debug(P9_DEBUG_9P,
1749                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1750                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1751                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1752                 "<<<    uid=%d gid=%d n_muid=%d\n",
1753                 ret->size, ret->type, ret->dev, ret->qid.type,
1754                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1755                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1756                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1757                 from_kuid(&init_user_ns, ret->n_uid),
1758                 from_kgid(&init_user_ns, ret->n_gid),
1759                 from_kuid(&init_user_ns, ret->n_muid));
1760
1761         p9_free_req(clnt, req);
1762         return ret;
1763
1764 error:
1765         kfree(ret);
1766         return ERR_PTR(err);
1767 }
1768 EXPORT_SYMBOL(p9_client_stat);
1769
1770 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1771                                                         u64 request_mask)
1772 {
1773         int err;
1774         struct p9_client *clnt;
1775         struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1776                                                                 GFP_KERNEL);
1777         struct p9_req_t *req;
1778
1779         p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1780                                                         fid->fid, request_mask);
1781
1782         if (!ret)
1783                 return ERR_PTR(-ENOMEM);
1784
1785         err = 0;
1786         clnt = fid->clnt;
1787
1788         req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1789         if (IS_ERR(req)) {
1790                 err = PTR_ERR(req);
1791                 goto error;
1792         }
1793
1794         err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1795         if (err) {
1796                 trace_9p_protocol_dump(clnt, req->rc);
1797                 p9_free_req(clnt, req);
1798                 goto error;
1799         }
1800
1801         p9_debug(P9_DEBUG_9P,
1802                 "<<< RGETATTR st_result_mask=%lld\n"
1803                 "<<< qid=%x.%llx.%x\n"
1804                 "<<< st_mode=%8.8x st_nlink=%llu\n"
1805                 "<<< st_uid=%d st_gid=%d\n"
1806                 "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1807                 "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1808                 "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1809                 "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1810                 "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1811                 "<<< st_gen=%lld st_data_version=%lld",
1812                 ret->st_result_mask, ret->qid.type, ret->qid.path,
1813                 ret->qid.version, ret->st_mode, ret->st_nlink,
1814                 from_kuid(&init_user_ns, ret->st_uid),
1815                 from_kgid(&init_user_ns, ret->st_gid),
1816                 ret->st_rdev, ret->st_size, ret->st_blksize,
1817                 ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1818                 ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1819                 ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1820                 ret->st_gen, ret->st_data_version);
1821
1822         p9_free_req(clnt, req);
1823         return ret;
1824
1825 error:
1826         kfree(ret);
1827         return ERR_PTR(err);
1828 }
1829 EXPORT_SYMBOL(p9_client_getattr_dotl);
1830
1831 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1832 {
1833         int ret;
1834
1835         /* NOTE: size shouldn't include its own length */
1836         /* size[2] type[2] dev[4] qid[13] */
1837         /* mode[4] atime[4] mtime[4] length[8]*/
1838         /* name[s] uid[s] gid[s] muid[s] */
1839         ret = 2+4+13+4+4+4+8+2+2+2+2;
1840
1841         if (wst->name)
1842                 ret += strlen(wst->name);
1843         if (wst->uid)
1844                 ret += strlen(wst->uid);
1845         if (wst->gid)
1846                 ret += strlen(wst->gid);
1847         if (wst->muid)
1848                 ret += strlen(wst->muid);
1849
1850         if ((proto_version == p9_proto_2000u) ||
1851                 (proto_version == p9_proto_2000L)) {
1852                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1853                 if (wst->extension)
1854                         ret += strlen(wst->extension);
1855         }
1856
1857         return ret;
1858 }
1859
1860 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1861 {
1862         int err;
1863         struct p9_req_t *req;
1864         struct p9_client *clnt;
1865
1866         err = 0;
1867         clnt = fid->clnt;
1868         wst->size = p9_client_statsize(wst, clnt->proto_version);
1869         p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1870         p9_debug(P9_DEBUG_9P,
1871                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1872                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1873                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1874                 "     uid=%d gid=%d n_muid=%d\n",
1875                 wst->size, wst->type, wst->dev, wst->qid.type,
1876                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1877                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1878                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1879                 from_kuid(&init_user_ns, wst->n_uid),
1880                 from_kgid(&init_user_ns, wst->n_gid),
1881                 from_kuid(&init_user_ns, wst->n_muid));
1882
1883         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1884         if (IS_ERR(req)) {
1885                 err = PTR_ERR(req);
1886                 goto error;
1887         }
1888
1889         p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1890
1891         p9_free_req(clnt, req);
1892 error:
1893         return err;
1894 }
1895 EXPORT_SYMBOL(p9_client_wstat);
1896
1897 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1898 {
1899         int err;
1900         struct p9_req_t *req;
1901         struct p9_client *clnt;
1902
1903         err = 0;
1904         clnt = fid->clnt;
1905         p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1906         p9_debug(P9_DEBUG_9P,
1907                 "    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1908                 "    atime_sec=%lld atime_nsec=%lld\n"
1909                 "    mtime_sec=%lld mtime_nsec=%lld\n",
1910                 p9attr->valid, p9attr->mode,
1911                 from_kuid(&init_user_ns, p9attr->uid),
1912                 from_kgid(&init_user_ns, p9attr->gid),
1913                 p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1914                 p9attr->mtime_sec, p9attr->mtime_nsec);
1915
1916         req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1917
1918         if (IS_ERR(req)) {
1919                 err = PTR_ERR(req);
1920                 goto error;
1921         }
1922         p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1923         p9_free_req(clnt, req);
1924 error:
1925         return err;
1926 }
1927 EXPORT_SYMBOL(p9_client_setattr);
1928
1929 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1930 {
1931         int err;
1932         struct p9_req_t *req;
1933         struct p9_client *clnt;
1934
1935         err = 0;
1936         clnt = fid->clnt;
1937
1938         p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1939
1940         req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1941         if (IS_ERR(req)) {
1942                 err = PTR_ERR(req);
1943                 goto error;
1944         }
1945
1946         err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1947                 &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1948                 &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1949         if (err) {
1950                 trace_9p_protocol_dump(clnt, req->rc);
1951                 p9_free_req(clnt, req);
1952                 goto error;
1953         }
1954
1955         p9_debug(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1956                 "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1957                 "fsid %llu namelen %ld\n",
1958                 fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1959                 sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1960                 sb->fsid, (long int)sb->namelen);
1961
1962         p9_free_req(clnt, req);
1963 error:
1964         return err;
1965 }
1966 EXPORT_SYMBOL(p9_client_statfs);
1967
1968 int p9_client_rename(struct p9_fid *fid,
1969                      struct p9_fid *newdirfid, const char *name)
1970 {
1971         int err;
1972         struct p9_req_t *req;
1973         struct p9_client *clnt;
1974
1975         err = 0;
1976         clnt = fid->clnt;
1977
1978         p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1979                         fid->fid, newdirfid->fid, name);
1980
1981         req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1982                         newdirfid->fid, name);
1983         if (IS_ERR(req)) {
1984                 err = PTR_ERR(req);
1985                 goto error;
1986         }
1987
1988         p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1989
1990         p9_free_req(clnt, req);
1991 error:
1992         return err;
1993 }
1994 EXPORT_SYMBOL(p9_client_rename);
1995
1996 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1997                        struct p9_fid *newdirfid, const char *new_name)
1998 {
1999         int err;
2000         struct p9_req_t *req;
2001         struct p9_client *clnt;
2002
2003         err = 0;
2004         clnt = olddirfid->clnt;
2005
2006         p9_debug(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
2007                    " newdirfid %d new name %s\n", olddirfid->fid, old_name,
2008                    newdirfid->fid, new_name);
2009
2010         req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
2011                             old_name, newdirfid->fid, new_name);
2012         if (IS_ERR(req)) {
2013                 err = PTR_ERR(req);
2014                 goto error;
2015         }
2016
2017         p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
2018                    newdirfid->fid, new_name);
2019
2020         p9_free_req(clnt, req);
2021 error:
2022         return err;
2023 }
2024 EXPORT_SYMBOL(p9_client_renameat);
2025
2026 /*
2027  * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
2028  */
2029 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
2030                                 const char *attr_name, u64 *attr_size)
2031 {
2032         int err;
2033         struct p9_req_t *req;
2034         struct p9_client *clnt;
2035         struct p9_fid *attr_fid;
2036
2037         err = 0;
2038         clnt = file_fid->clnt;
2039         attr_fid = p9_fid_create(clnt);
2040         if (IS_ERR(attr_fid)) {
2041                 err = PTR_ERR(attr_fid);
2042                 attr_fid = NULL;
2043                 goto error;
2044         }
2045         p9_debug(P9_DEBUG_9P,
2046                 ">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
2047                 file_fid->fid, attr_fid->fid, attr_name);
2048
2049         req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
2050                         file_fid->fid, attr_fid->fid, attr_name);
2051         if (IS_ERR(req)) {
2052                 err = PTR_ERR(req);
2053                 goto error;
2054         }
2055         err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
2056         if (err) {
2057                 trace_9p_protocol_dump(clnt, req->rc);
2058                 p9_free_req(clnt, req);
2059                 goto clunk_fid;
2060         }
2061         p9_free_req(clnt, req);
2062         p9_debug(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
2063                 attr_fid->fid, *attr_size);
2064         return attr_fid;
2065 clunk_fid:
2066         p9_client_clunk(attr_fid);
2067         attr_fid = NULL;
2068 error:
2069         if (attr_fid && (attr_fid != file_fid))
2070                 p9_fid_destroy(attr_fid);
2071
2072         return ERR_PTR(err);
2073 }
2074 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
2075
2076 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
2077                         u64 attr_size, int flags)
2078 {
2079         int err;
2080         struct p9_req_t *req;
2081         struct p9_client *clnt;
2082
2083         p9_debug(P9_DEBUG_9P,
2084                 ">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
2085                 fid->fid, name, (long long)attr_size, flags);
2086         err = 0;
2087         clnt = fid->clnt;
2088         req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2089                         fid->fid, name, attr_size, flags);
2090         if (IS_ERR(req)) {
2091                 err = PTR_ERR(req);
2092                 goto error;
2093         }
2094         p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2095         p9_free_req(clnt, req);
2096 error:
2097         return err;
2098 }
2099 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2100
2101 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2102 {
2103         int err, rsize, non_zc = 0;
2104         struct p9_client *clnt;
2105         struct p9_req_t *req;
2106         char *dataptr;
2107         struct kvec kv = {.iov_base = data, .iov_len = count};
2108         struct iov_iter to;
2109
2110         iov_iter_kvec(&to, READ | ITER_KVEC, &kv, 1, count);
2111
2112         p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2113                                 fid->fid, (unsigned long long) offset, count);
2114
2115         err = 0;
2116         clnt = fid->clnt;
2117
2118         rsize = fid->iounit;
2119         if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2120                 rsize = clnt->msize - P9_READDIRHDRSZ;
2121
2122         if (count < rsize)
2123                 rsize = count;
2124
2125         /* Don't bother zerocopy for small IO (< 1024) */
2126         if (clnt->trans_mod->zc_request && rsize > 1024) {
2127                 /*
2128                  * response header len is 11
2129                  * PDU Header(7) + IO Size (4)
2130                  */
2131                 req = p9_client_zc_rpc(clnt, P9_TREADDIR, &to, NULL, rsize, 0,
2132                                        11, "dqd", fid->fid, offset, rsize);
2133         } else {
2134                 non_zc = 1;
2135                 req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2136                                     offset, rsize);
2137         }
2138         if (IS_ERR(req)) {
2139                 err = PTR_ERR(req);
2140                 goto error;
2141         }
2142
2143         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2144         if (err) {
2145                 trace_9p_protocol_dump(clnt, req->rc);
2146                 goto free_and_error;
2147         }
2148         if (rsize < count) {
2149                 pr_err("bogus RREADDIR count (%d > %d)\n", count, rsize);
2150                 count = rsize;
2151         }
2152
2153         p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2154
2155         if (non_zc)
2156                 memmove(data, dataptr, count);
2157
2158         p9_free_req(clnt, req);
2159         return count;
2160
2161 free_and_error:
2162         p9_free_req(clnt, req);
2163 error:
2164         return err;
2165 }
2166 EXPORT_SYMBOL(p9_client_readdir);
2167
2168 int p9_client_mknod_dotl(struct p9_fid *fid, const char *name, int mode,
2169                         dev_t rdev, kgid_t gid, struct p9_qid *qid)
2170 {
2171         int err;
2172         struct p9_client *clnt;
2173         struct p9_req_t *req;
2174
2175         err = 0;
2176         clnt = fid->clnt;
2177         p9_debug(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2178                 "minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2179         req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddg", fid->fid, name, mode,
2180                 MAJOR(rdev), MINOR(rdev), gid);
2181         if (IS_ERR(req))
2182                 return PTR_ERR(req);
2183
2184         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2185         if (err) {
2186                 trace_9p_protocol_dump(clnt, req->rc);
2187                 goto error;
2188         }
2189         p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2190                                 (unsigned long long)qid->path, qid->version);
2191
2192 error:
2193         p9_free_req(clnt, req);
2194         return err;
2195
2196 }
2197 EXPORT_SYMBOL(p9_client_mknod_dotl);
2198
2199 int p9_client_mkdir_dotl(struct p9_fid *fid, const char *name, int mode,
2200                                 kgid_t gid, struct p9_qid *qid)
2201 {
2202         int err;
2203         struct p9_client *clnt;
2204         struct p9_req_t *req;
2205
2206         err = 0;
2207         clnt = fid->clnt;
2208         p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2209                  fid->fid, name, mode, from_kgid(&init_user_ns, gid));
2210         req = p9_client_rpc(clnt, P9_TMKDIR, "dsdg", fid->fid, name, mode,
2211                 gid);
2212         if (IS_ERR(req))
2213                 return PTR_ERR(req);
2214
2215         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2216         if (err) {
2217                 trace_9p_protocol_dump(clnt, req->rc);
2218                 goto error;
2219         }
2220         p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2221                                 (unsigned long long)qid->path, qid->version);
2222
2223 error:
2224         p9_free_req(clnt, req);
2225         return err;
2226
2227 }
2228 EXPORT_SYMBOL(p9_client_mkdir_dotl);
2229
2230 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2231 {
2232         int err;
2233         struct p9_client *clnt;
2234         struct p9_req_t *req;
2235
2236         err = 0;
2237         clnt = fid->clnt;
2238         p9_debug(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2239                         "start %lld length %lld proc_id %d client_id %s\n",
2240                         fid->fid, flock->type, flock->flags, flock->start,
2241                         flock->length, flock->proc_id, flock->client_id);
2242
2243         req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2244                                 flock->flags, flock->start, flock->length,
2245                                         flock->proc_id, flock->client_id);
2246
2247         if (IS_ERR(req))
2248                 return PTR_ERR(req);
2249
2250         err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2251         if (err) {
2252                 trace_9p_protocol_dump(clnt, req->rc);
2253                 goto error;
2254         }
2255         p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2256 error:
2257         p9_free_req(clnt, req);
2258         return err;
2259
2260 }
2261 EXPORT_SYMBOL(p9_client_lock_dotl);
2262
2263 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2264 {
2265         int err;
2266         struct p9_client *clnt;
2267         struct p9_req_t *req;
2268
2269         err = 0;
2270         clnt = fid->clnt;
2271         p9_debug(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
2272                 "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2273                 glock->start, glock->length, glock->proc_id, glock->client_id);
2274
2275         req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
2276                 glock->start, glock->length, glock->proc_id, glock->client_id);
2277
2278         if (IS_ERR(req))
2279                 return PTR_ERR(req);
2280
2281         err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2282                         &glock->start, &glock->length, &glock->proc_id,
2283                         &glock->client_id);
2284         if (err) {
2285                 trace_9p_protocol_dump(clnt, req->rc);
2286                 goto error;
2287         }
2288         p9_debug(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2289                 "proc_id %d client_id %s\n", glock->type, glock->start,
2290                 glock->length, glock->proc_id, glock->client_id);
2291 error:
2292         p9_free_req(clnt, req);
2293         return err;
2294 }
2295 EXPORT_SYMBOL(p9_client_getlock_dotl);
2296
2297 int p9_client_readlink(struct p9_fid *fid, char **target)
2298 {
2299         int err;
2300         struct p9_client *clnt;
2301         struct p9_req_t *req;
2302
2303         err = 0;
2304         clnt = fid->clnt;
2305         p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2306
2307         req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2308         if (IS_ERR(req))
2309                 return PTR_ERR(req);
2310
2311         err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2312         if (err) {
2313                 trace_9p_protocol_dump(clnt, req->rc);
2314                 goto error;
2315         }
2316         p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2317 error:
2318         p9_free_req(clnt, req);
2319         return err;
2320 }
2321 EXPORT_SYMBOL(p9_client_readlink);