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