net/9p/client.c

   1 /*
   2  * net/9p/clnt.c
   3  *
   4  * 9P Client
   5  *
   6  *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
   7  *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License version 2
  11  *  as published by the Free Software Foundation.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to:
  20  *  Free Software Foundation
  21  *  51 Franklin Street, Fifth Floor
  22  *  Boston, MA  02111-1301  USA
  23  *
  24  */
  25
  26 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  27
  28 #include <linux/module.h>
  29 #include <linux/errno.h>
  30 #include <linux/fs.h>
  31 #include <linux/poll.h>
  32 #include <linux/idr.h>
  33 #include <linux/mutex.h>
  34 #include <linux/slab.h>
  35 #include <linux/sched.h>
  36 #include <linux/uaccess.h>
  37 #include <net/9p/9p.h>
  38 #include <linux/parser.h>
  39 #include <net/9p/client.h>
  40 #include <net/9p/transport.h>
  41 #include "protocol.h"
  42
  43 #define CREATE_TRACE_POINTS
  44 #include <trace/events/9p.h>
  45
  46 /*
  47   * Client Option Parsing (code inspired by NFS code)
  48   *  - a little lazy - parse all client options
  49   */
  50
  51 enum {
  52         Opt_msize,
  53         Opt_trans,
  54         Opt_legacy,
  55         Opt_version,
  56         Opt_err,
  57 };
  58
  59 static const match_table_t tokens = {
  60         {Opt_msize, "msize=%u"},
  61         {Opt_legacy, "noextend"},
  62         {Opt_trans, "trans=%s"},
  63         {Opt_version, "version=%s"},
  64         {Opt_err, NULL},
  65 };
  66
  67 inline int p9_is_proto_dotl(struct p9_client *clnt)
  68 {
  69         return clnt->proto_version == p9_proto_2000L;
  70 }
  71 EXPORT_SYMBOL(p9_is_proto_dotl);
  72
  73 inline int p9_is_proto_dotu(struct p9_client *clnt)
  74 {
  75         return clnt->proto_version == p9_proto_2000u;
  76 }
  77 EXPORT_SYMBOL(p9_is_proto_dotu);
  78
  79 /*
  80  * Some error codes are taken directly from the server replies,
  81  * make sure they are valid.
  82  */
  83 static int safe_errno(int err)
  84 {
  85         if ((err > 0) || (err < -MAX_ERRNO)) {
  86                 p9_debug(P9_DEBUG_ERROR, "Invalid error code %d\n", err);
  87                 return -EPROTO;
  88         }
  89         return err;
  90 }
  91
  92
  93 /* Interpret mount option for protocol version */
  94 static int get_protocol_version(char *s)
  95 {
  96         int version = -EINVAL;
  97
  98         if (!strcmp(s, "9p2000")) {
  99                 version = p9_proto_legacy;
 100                 p9_debug(P9_DEBUG_9P, "Protocol version: Legacy\n");
 101         } else if (!strcmp(s, "9p2000.u")) {
 102                 version = p9_proto_2000u;
 103                 p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
 104         } else if (!strcmp(s, "9p2000.L")) {
 105                 version = p9_proto_2000L;
 106                 p9_debug(P9_DEBUG_9P, "Protocol version: 9P2000.L\n");
 107         } else
 108                 pr_info("Unknown protocol version %s\n", s);
 109
 110         return version;
 111 }
 112
 113 /**
 114  * parse_options - parse mount options into client structure
 115  * @opts: options string passed from mount
 116  * @clnt: existing v9fs client information
 117  *
 118  * Return 0 upon success, -ERRNO upon failure
 119  */
 120
 121 static int parse_opts(char *opts, struct p9_client *clnt)
 122 {
 123         char *options, *tmp_options;
 124         char *p;
 125         substring_t args[MAX_OPT_ARGS];
 126         int option;
 127         char *s;
 128         int ret = 0;
 129
 130         clnt->proto_version = p9_proto_2000u;
 131         clnt->msize = 8192;
 132
 133         if (!opts)
 134                 return 0;
 135
 136         tmp_options = kstrdup(opts, GFP_KERNEL);
 137         if (!tmp_options) {
 138                 p9_debug(P9_DEBUG_ERROR,
 139                          "failed to allocate copy of option string\n");
 140                 return -ENOMEM;
 141         }
 142         options = tmp_options;
 143
 144         while ((p = strsep(&options, ",")) != NULL) {
 145                 int token, r;
 146                 if (!*p)
 147                         continue;
 148                 token = match_token(p, tokens, args);
 149                 switch (token) {
 150                 case Opt_msize:
 151                         r = match_int(&args[0], &option);
 152                         if (r < 0) {
 153                                 p9_debug(P9_DEBUG_ERROR,
 154                                          "integer field, but no integer?\n");
 155                                 ret = r;
 156                                 continue;
 157                         }
 158                         clnt->msize = option;
 159                         break;
 160                 case Opt_trans:
 161                         s = match_strdup(&args[0]);
 162                         if (!s) {
 163                                 ret = -ENOMEM;
 164                                 p9_debug(P9_DEBUG_ERROR,
 165                                          "problem allocating copy of trans arg\n");
 166                                 goto free_and_return;
 167                          }
 168                         clnt->trans_mod = v9fs_get_trans_by_name(s);
 169                         if (clnt->trans_mod == NULL) {
 170                                 pr_info("Could not find request transport: %s\n",
 171                                         s);
 172                                 ret = -EINVAL;
 173                                 kfree(s);
 174                                 goto free_and_return;
 175                         }
 176                         kfree(s);
 177                         break;
 178                 case Opt_legacy:
 179                         clnt->proto_version = p9_proto_legacy;
 180                         break;
 181                 case Opt_version:
 182                         s = match_strdup(&args[0]);
 183                         if (!s) {
 184                                 ret = -ENOMEM;
 185                                 p9_debug(P9_DEBUG_ERROR,
 186                                          "problem allocating copy of version arg\n");
 187                                 goto free_and_return;
 188                         }
 189                         ret = get_protocol_version(s);
 190                         if (ret == -EINVAL) {
 191                                 kfree(s);
 192                                 goto free_and_return;
 193                         }
 194                         kfree(s);
 195                         clnt->proto_version = ret;
 196                         break;
 197                 default:
 198                         continue;
 199                 }
 200         }
 201
 202 free_and_return:
 203         kfree(tmp_options);
 204         return ret;
 205 }
 206
 207 /**
 208  * p9_tag_alloc - lookup/allocate a request by tag
 209  * @c: client session to lookup tag within
 210  * @tag: numeric id for transaction
 211  *
 212  * this is a simple array lookup, but will grow the
 213  * request_slots as necessary to accommodate transaction
 214  * ids which did not previously have a slot.
 215  *
 216  * this code relies on the client spinlock to manage locks, its
 217  * possible we should switch to something else, but I'd rather
 218  * stick with something low-overhead for the common case.
 219  *
 220  */
 221
 222 static struct p9_req_t *
 223 p9_tag_alloc(struct p9_client *c, u16 tag, unsigned int max_size)
 224 {
 225         unsigned long flags;
 226         int row, col;
 227         struct p9_req_t *req;
 228         int alloc_msize = min(c->msize, max_size);
 229
 230         /* This looks up the original request by tag so we know which
 231          * buffer to read the data into */
 232         tag++;
 233
 234         if (tag >= c->max_tag) {
 235                 spin_lock_irqsave(&c->lock, flags);
 236                 /* check again since original check was outside of lock */
 237                 while (tag >= c->max_tag) {
 238                         row = (tag / P9_ROW_MAXTAG);
 239                         c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
 240                                         sizeof(struct p9_req_t), GFP_ATOMIC);
 241
 242                         if (!c->reqs[row]) {
 243                                 pr_err("Couldn't grow tag array\n");
 244                                 spin_unlock_irqrestore(&c->lock, flags);
 245                                 return ERR_PTR(-ENOMEM);
 246                         }
 247                         for (col = 0; col < P9_ROW_MAXTAG; col++) {
 248                                 c->reqs[row][col].status = REQ_STATUS_IDLE;
 249                                 c->reqs[row][col].tc = NULL;
 250                         }
 251                         c->max_tag += P9_ROW_MAXTAG;
 252                 }
 253                 spin_unlock_irqrestore(&c->lock, flags);
 254         }
 255         row = tag / P9_ROW_MAXTAG;
 256         col = tag % P9_ROW_MAXTAG;
 257
 258         req = &c->reqs[row][col];
 259         if (!req->tc) {
 260                 req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_NOFS);
 261                 if (!req->wq) {
 262                         pr_err("Couldn't grow tag array\n");
 263                         return ERR_PTR(-ENOMEM);
 264                 }
 265                 init_waitqueue_head(req->wq);
 266                 req->tc = kmalloc(sizeof(struct p9_fcall) + alloc_msize,
 267                                   GFP_NOFS);
 268                 req->rc = kmalloc(sizeof(struct p9_fcall) + alloc_msize,
 269                                   GFP_NOFS);
 270                 if ((!req->tc) || (!req->rc)) {
 271                         pr_err("Couldn't grow tag array\n");
 272                         kfree(req->tc);
 273                         kfree(req->rc);
 274                         kfree(req->wq);
 275                         req->tc = req->rc = NULL;
 276                         req->wq = NULL;
 277                         return ERR_PTR(-ENOMEM);
 278                 }
 279                 req->tc->capacity = alloc_msize;
 280                 req->rc->capacity = alloc_msize;
 281                 req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
 282                 req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall);
 283         }
 284
 285         p9pdu_reset(req->tc);
 286         p9pdu_reset(req->rc);
 287
 288         req->tc->tag = tag-1;
 289         req->status = REQ_STATUS_ALLOC;
 290
 291         return &c->reqs[row][col];
 292 }
 293
 294 /**
 295  * p9_tag_lookup - lookup a request by tag
 296  * @c: client session to lookup tag within
 297  * @tag: numeric id for transaction
 298  *
 299  */
 300
 301 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
 302 {
 303         int row, col;
 304
 305         /* This looks up the original request by tag so we know which
 306          * buffer to read the data into */
 307         tag++;
 308
 309         if(tag >= c->max_tag)
 310                 return NULL;
 311
 312         row = tag / P9_ROW_MAXTAG;
 313         col = tag % P9_ROW_MAXTAG;
 314
 315         return &c->reqs[row][col];
 316 }
 317 EXPORT_SYMBOL(p9_tag_lookup);
 318
 319 /**
 320  * p9_tag_init - setup tags structure and contents
 321  * @c:  v9fs client struct
 322  *
 323  * This initializes the tags structure for each client instance.
 324  *
 325  */
 326
 327 static int p9_tag_init(struct p9_client *c)
 328 {
 329         int err = 0;
 330
 331         c->tagpool = p9_idpool_create();
 332         if (IS_ERR(c->tagpool)) {
 333                 err = PTR_ERR(c->tagpool);
 334                 goto error;
 335         }
 336         err = p9_idpool_get(c->tagpool); /* reserve tag 0 */
 337         if (err < 0) {
 338                 p9_idpool_destroy(c->tagpool);
 339                 goto error;
 340         }
 341         c->max_tag = 0;
 342 error:
 343         return err;
 344 }
 345
 346 /**
 347  * p9_tag_cleanup - cleans up tags structure and reclaims resources
 348  * @c:  v9fs client struct
 349  *
 350  * This frees resources associated with the tags structure
 351  *
 352  */
 353 static void p9_tag_cleanup(struct p9_client *c)
 354 {
 355         int row, col;
 356
 357         /* check to insure all requests are idle */
 358         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 359                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 360                         if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
 361                                 p9_debug(P9_DEBUG_MUX,
 362                                          "Attempting to cleanup non-free tag %d,%d\n",
 363                                          row, col);
 364                                 /* TODO: delay execution of cleanup */
 365                                 return;
 366                         }
 367                 }
 368         }
 369
 370         if (c->tagpool) {
 371                 p9_idpool_put(0, c->tagpool); /* free reserved tag 0 */
 372                 p9_idpool_destroy(c->tagpool);
 373         }
 374
 375         /* free requests associated with tags */
 376         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 377                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 378                         kfree(c->reqs[row][col].wq);
 379                         kfree(c->reqs[row][col].tc);
 380                         kfree(c->reqs[row][col].rc);
 381                 }
 382                 kfree(c->reqs[row]);
 383         }
 384         c->max_tag = 0;
 385 }
 386
 387 /**
 388  * p9_free_req - free a request and clean-up as necessary
 389  * c: client state
 390  * r: request to release
 391  *
 392  */
 393
 394 static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
 395 {
 396         int tag = r->tc->tag;
 397         p9_debug(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
 398
 399         r->status = REQ_STATUS_IDLE;
 400         if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
 401                 p9_idpool_put(tag, c->tagpool);
 402 }
 403
 404 /**
 405  * p9_client_cb - call back from transport to client
 406  * c: client state
 407  * req: request received
 408  *
 409  */
 410 void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
 411 {
 412         p9_debug(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
 413         wake_up(req->wq);
 414         p9_debug(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
 415 }
 416 EXPORT_SYMBOL(p9_client_cb);
 417
 418 /**
 419  * p9_parse_header - parse header arguments out of a packet
 420  * @pdu: packet to parse
 421  * @size: size of packet
 422  * @type: type of request
 423  * @tag: tag of packet
 424  * @rewind: set if we need to rewind offset afterwards
 425  */
 426
 427 int
 428 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
 429                                                                 int rewind)
 430 {
 431         int8_t r_type;
 432         int16_t r_tag;
 433         int32_t r_size;
 434         int offset = pdu->offset;
 435         int err;
 436
 437         pdu->offset = 0;
 438         if (pdu->size == 0)
 439                 pdu->size = 7;
 440
 441         err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
 442         if (err)
 443                 goto rewind_and_exit;
 444
 445         pdu->size = r_size;
 446         pdu->id = r_type;
 447         pdu->tag = r_tag;
 448
 449         p9_debug(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n",
 450                  pdu->size, pdu->id, pdu->tag);
 451
 452         if (type)
 453                 *type = r_type;
 454         if (tag)
 455                 *tag = r_tag;
 456         if (size)
 457                 *size = r_size;
 458
 459
 460 rewind_and_exit:
 461         if (rewind)
 462                 pdu->offset = offset;
 463         return err;
 464 }
 465 EXPORT_SYMBOL(p9_parse_header);
 466
 467 /**
 468  * p9_check_errors - check 9p packet for error return and process it
 469  * @c: current client instance
 470  * @req: request to parse and check for error conditions
 471  *
 472  * returns error code if one is discovered, otherwise returns 0
 473  *
 474  * this will have to be more complicated if we have multiple
 475  * error packet types
 476  */
 477
 478 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 479 {
 480         int8_t type;
 481         int err;
 482         int ecode;
 483
 484         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 485         /*
 486          * dump the response from server
 487          * This should be after check errors which poplulate pdu_fcall.
 488          */
 489         trace_9p_protocol_dump(c, req->rc);
 490         if (err) {
 491                 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 492                 return err;
 493         }
 494         if (type != P9_RERROR && type != P9_RLERROR)
 495                 return 0;
 496
 497         if (!p9_is_proto_dotl(c)) {
 498                 char *ename;
 499                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 500                                   &ename, &ecode);
 501                 if (err)
 502                         goto out_err;
 503
 504                 if (p9_is_proto_dotu(c))
 505                         err = -ecode;
 506
 507                 if (!err || !IS_ERR_VALUE(err)) {
 508                         err = p9_errstr2errno(ename, strlen(ename));
 509
 510                         p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 511                                  -ecode, ename);
 512                 }
 513                 kfree(ename);
 514         } else {
 515                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 516                 err = -ecode;
 517
 518                 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 519         }
 520
 521         return err;
 522
 523 out_err:
 524         p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 525
 526         return err;
 527 }
 528
 529 /**
 530  * p9_check_zc_errors - check 9p packet for error return and process it
 531  * @c: current client instance
 532  * @req: request to parse and check for error conditions
 533  * @in_hdrlen: Size of response protocol buffer.
 534  *
 535  * returns error code if one is discovered, otherwise returns 0
 536  *
 537  * this will have to be more complicated if we have multiple
 538  * error packet types
 539  */
 540
 541 static int p9_check_zc_errors(struct p9_client *c, struct p9_req_t *req,
 542                               char *uidata, int in_hdrlen, int kern_buf)
 543 {
 544         int err;
 545         int ecode;
 546         int8_t type;
 547         char *ename = NULL;
 548
 549         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 550         /*
 551          * dump the response from server
 552          * This should be after parse_header which poplulate pdu_fcall.
 553          */
 554         trace_9p_protocol_dump(c, req->rc);
 555         if (err) {
 556                 p9_debug(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 557                 return err;
 558         }
 559
 560         if (type != P9_RERROR && type != P9_RLERROR)
 561                 return 0;
 562
 563         if (!p9_is_proto_dotl(c)) {
 564                 /* Error is reported in string format */
 565                 int len;
 566                 /* 7 = header size for RERROR; */
 567                 int inline_len = in_hdrlen - 7;
 568
 569                 len =  req->rc->size - req->rc->offset;
 570                 if (len > (P9_ZC_HDR_SZ - 7)) {
 571                         err = -EFAULT;
 572                         goto out_err;
 573                 }
 574
 575                 ename = &req->rc->sdata[req->rc->offset];
 576                 if (len > inline_len) {
 577                         /* We have error in external buffer */
 578                         if (kern_buf) {
 579                                 memcpy(ename + inline_len, uidata,
 580                                        len - inline_len);
 581                         } else {
 582                                 err = copy_from_user(ename + inline_len,
 583                                                      uidata, len - inline_len);
 584                                 if (err) {
 585                                         err = -EFAULT;
 586                                         goto out_err;
 587                                 }
 588                         }
 589                 }
 590                 ename = NULL;
 591                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 592                                   &ename, &ecode);
 593                 if (err)
 594                         goto out_err;
 595
 596                 if (p9_is_proto_dotu(c))
 597                         err = -ecode;
 598
 599                 if (!err || !IS_ERR_VALUE(err)) {
 600                         err = p9_errstr2errno(ename, strlen(ename));
 601
 602                         p9_debug(P9_DEBUG_9P, "<<< RERROR (%d) %s\n",
 603                                  -ecode, ename);
 604                 }
 605                 kfree(ename);
 606         } else {
 607                 err = p9pdu_readf(req->rc, c->proto_version, "d", &ecode);
 608                 err = -ecode;
 609
 610                 p9_debug(P9_DEBUG_9P, "<<< RLERROR (%d)\n", -ecode);
 611         }
 612         return err;
 613
 614 out_err:
 615         p9_debug(P9_DEBUG_ERROR, "couldn't parse error%d\n", err);
 616         return err;
 617 }
 618
 619 static struct p9_req_t *
 620 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
 621
 622 /**
 623  * p9_client_flush - flush (cancel) a request
 624  * @c: client state
 625  * @oldreq: request to cancel
 626  *
 627  * This sents a flush for a particular request and links
 628  * the flush request to the original request.  The current
 629  * code only supports a single flush request although the protocol
 630  * allows for multiple flush requests to be sent for a single request.
 631  *
 632  */
 633
 634 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 635 {
 636         struct p9_req_t *req;
 637         int16_t oldtag;
 638         int err;
 639
 640         err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
 641         if (err)
 642                 return err;
 643
 644         p9_debug(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
 645
 646         req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
 647         if (IS_ERR(req))
 648                 return PTR_ERR(req);
 649
 650
 651         /* if we haven't received a response for oldreq,
 652            remove it from the list. */
 653         spin_lock(&c->lock);
 654         if (oldreq->status == REQ_STATUS_FLSH)
 655                 list_del(&oldreq->req_list);
 656         spin_unlock(&c->lock);
 657
 658         p9_free_req(c, req);
 659         return 0;
 660 }
 661
 662 static struct p9_req_t *p9_client_prepare_req(struct p9_client *c,
 663                                               int8_t type, int req_size,
 664                                               const char *fmt, va_list ap)
 665 {
 666         int tag, err;
 667         struct p9_req_t *req;
 668
 669         p9_debug(P9_DEBUG_MUX, "client %p op %d\n", c, type);
 670
 671         /* we allow for any status other than disconnected */
 672         if (c->status == Disconnected)
 673                 return ERR_PTR(-EIO);
 674
 675         /* if status is begin_disconnected we allow only clunk request */
 676         if ((c->status == BeginDisconnect) && (type != P9_TCLUNK))
 677                 return ERR_PTR(-EIO);
 678
 679         tag = P9_NOTAG;
 680         if (type != P9_TVERSION) {
 681                 tag = p9_idpool_get(c->tagpool);
 682                 if (tag < 0)
 683                         return ERR_PTR(-ENOMEM);
 684         }
 685
 686         req = p9_tag_alloc(c, tag, req_size);
 687         if (IS_ERR(req))
 688                 return req;
 689
 690         /* marshall the data */
 691         p9pdu_prepare(req->tc, tag, type);
 692         err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
 693         if (err)
 694                 goto reterr;
 695         p9pdu_finalize(c, req->tc);
 696         trace_9p_client_req(c, type, tag);
 697         return req;
 698 reterr:
 699         p9_free_req(c, req);
 700         return ERR_PTR(err);
 701 }
 702
 703 /**
 704  * p9_client_rpc - issue a request and wait for a response
 705  * @c: client session
 706  * @type: type of request
 707  * @fmt: protocol format string (see protocol.c)
 708  *
 709  * Returns request structure (which client must free using p9_free_req)
 710  */
 711
 712 static struct p9_req_t *
 713 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 714 {
 715         va_list ap;
 716         int sigpending, err;
 717         unsigned long flags;
 718         struct p9_req_t *req;
 719
 720         va_start(ap, fmt);
 721         req = p9_client_prepare_req(c, type, c->msize, fmt, ap);
 722         va_end(ap);
 723         if (IS_ERR(req))
 724                 return req;
 725
 726         if (signal_pending(current)) {
 727                 sigpending = 1;
 728                 clear_thread_flag(TIF_SIGPENDING);
 729         } else
 730                 sigpending = 0;
 731
 732         err = c->trans_mod->request(c, req);
 733         if (err < 0) {
 734                 if (err != -ERESTARTSYS && err != -EFAULT)
 735                         c->status = Disconnected;
 736                 goto reterr;
 737         }
 738 again:
 739         /* Wait for the response */
 740         err = wait_event_interruptible(*req->wq,
 741                                        req->status >= REQ_STATUS_RCVD);
 742
 743         if ((err == -ERESTARTSYS) && (c->status == Connected)
 744                                   && (type == P9_TFLUSH)) {
 745                 sigpending = 1;
 746                 clear_thread_flag(TIF_SIGPENDING);
 747                 goto again;
 748         }
 749
 750         if (req->status == REQ_STATUS_ERROR) {
 751                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 752                 err = req->t_err;
 753         }
 754         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 755                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 756                 sigpending = 1;
 757                 clear_thread_flag(TIF_SIGPENDING);
 758
 759                 if (c->trans_mod->cancel(c, req))
 760                         p9_client_flush(c, req);
 761
 762                 /* if we received the response anyway, don't signal error */
 763                 if (req->status == REQ_STATUS_RCVD)
 764                         err = 0;
 765         }
 766         if (sigpending) {
 767                 spin_lock_irqsave(&current->sighand->siglock, flags);
 768                 recalc_sigpending();
 769                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 770         }
 771         if (err < 0)
 772                 goto reterr;
 773
 774         err = p9_check_errors(c, req);
 775         trace_9p_client_res(c, type, req->rc->tag, err);
 776         if (!err)
 777                 return req;
 778 reterr:
 779         p9_free_req(c, req);
 780         return ERR_PTR(safe_errno(err));
 781 }
 782
 783 /**
 784  * p9_client_zc_rpc - issue a request and wait for a response
 785  * @c: client session
 786  * @type: type of request
 787  * @uidata: user bffer that should be ued for zero copy read
 788  * @uodata: user buffer that shoud be user for zero copy write
 789  * @inlen: read buffer size
 790  * @olen: write buffer size
 791  * @hdrlen: reader header size, This is the size of response protocol data
 792  * @fmt: protocol format string (see protocol.c)
 793  *
 794  * Returns request structure (which client must free using p9_free_req)
 795  */
 796 static struct p9_req_t *p9_client_zc_rpc(struct p9_client *c, int8_t type,
 797                                          char *uidata, char *uodata,
 798                                          int inlen, int olen, int in_hdrlen,
 799                                          int kern_buf, const char *fmt, ...)
 800 {
 801         va_list ap;
 802         int sigpending, err;
 803         unsigned long flags;
 804         struct p9_req_t *req;
 805
 806         va_start(ap, fmt);
 807         /*
 808          * We allocate a inline protocol data of only 4k bytes.
 809          * The actual content is passed in zero-copy fashion.
 810          */
 811         req = p9_client_prepare_req(c, type, P9_ZC_HDR_SZ, fmt, ap);
 812         va_end(ap);
 813         if (IS_ERR(req))
 814                 return req;
 815
 816         if (signal_pending(current)) {
 817                 sigpending = 1;
 818                 clear_thread_flag(TIF_SIGPENDING);
 819         } else
 820                 sigpending = 0;
 821
 822         /* If we are called with KERNEL_DS force kern_buf */
 823         if (segment_eq(get_fs(), KERNEL_DS))
 824                 kern_buf = 1;
 825
 826         err = c->trans_mod->zc_request(c, req, uidata, uodata,
 827                                        inlen, olen, in_hdrlen, kern_buf);
 828         if (err < 0) {
 829                 if (err == -EIO)
 830                         c->status = Disconnected;
 831                 if (err != -ERESTARTSYS)
 832                         goto reterr;
 833         }
 834         if (req->status == REQ_STATUS_ERROR) {
 835                 p9_debug(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 836                 err = req->t_err;
 837         }
 838         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 839                 p9_debug(P9_DEBUG_MUX, "flushing\n");
 840                 sigpending = 1;
 841                 clear_thread_flag(TIF_SIGPENDING);
 842
 843                 if (c->trans_mod->cancel(c, req))
 844                         p9_client_flush(c, req);
 845
 846                 /* if we received the response anyway, don't signal error */
 847                 if (req->status == REQ_STATUS_RCVD)
 848                         err = 0;
 849         }
 850         if (sigpending) {
 851                 spin_lock_irqsave(&current->sighand->siglock, flags);
 852                 recalc_sigpending();
 853                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 854         }
 855         if (err < 0)
 856                 goto reterr;
 857
 858         err = p9_check_zc_errors(c, req, uidata, in_hdrlen, kern_buf);
 859         trace_9p_client_res(c, type, req->rc->tag, err);
 860         if (!err)
 861                 return req;
 862 reterr:
 863         p9_free_req(c, req);
 864         return ERR_PTR(safe_errno(err));
 865 }
 866
 867 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 868 {
 869         int ret;
 870         struct p9_fid *fid;
 871         unsigned long flags;
 872
 873         p9_debug(P9_DEBUG_FID, "clnt %p\n", clnt);
 874         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
 875         if (!fid)
 876                 return ERR_PTR(-ENOMEM);
 877
 878         ret = p9_idpool_get(clnt->fidpool);
 879         if (ret < 0) {
 880                 ret = -ENOSPC;
 881                 goto error;
 882         }
 883         fid->fid = ret;
 884
 885         memset(&fid->qid, 0, sizeof(struct p9_qid));
 886         fid->mode = -1;
 887         fid->uid = current_fsuid();
 888         fid->clnt = clnt;
 889         fid->rdir = NULL;
 890         spin_lock_irqsave(&clnt->lock, flags);
 891         list_add(&fid->flist, &clnt->fidlist);
 892         spin_unlock_irqrestore(&clnt->lock, flags);
 893
 894         return fid;
 895
 896 error:
 897         kfree(fid);
 898         return ERR_PTR(ret);
 899 }
 900
 901 static void p9_fid_destroy(struct p9_fid *fid)
 902 {
 903         struct p9_client *clnt;
 904         unsigned long flags;
 905
 906         p9_debug(P9_DEBUG_FID, "fid %d\n", fid->fid);
 907         clnt = fid->clnt;
 908         p9_idpool_put(fid->fid, clnt->fidpool);
 909         spin_lock_irqsave(&clnt->lock, flags);
 910         list_del(&fid->flist);
 911         spin_unlock_irqrestore(&clnt->lock, flags);
 912         kfree(fid->rdir);
 913         kfree(fid);
 914 }
 915
 916 static int p9_client_version(struct p9_client *c)
 917 {
 918         int err = 0;
 919         struct p9_req_t *req;
 920         char *version;
 921         int msize;
 922
 923         p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
 924                  c->msize, c->proto_version);
 925
 926         switch (c->proto_version) {
 927         case p9_proto_2000L:
 928                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 929                                         c->msize, "9P2000.L");
 930                 break;
 931         case p9_proto_2000u:
 932                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 933                                         c->msize, "9P2000.u");
 934                 break;
 935         case p9_proto_legacy:
 936                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 937                                         c->msize, "9P2000");
 938                 break;
 939         default:
 940                 return -EINVAL;
 941                 break;
 942         }
 943
 944         if (IS_ERR(req))
 945                 return PTR_ERR(req);
 946
 947         err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
 948         if (err) {
 949                 p9_debug(P9_DEBUG_9P, "version error %d\n", err);
 950                 trace_9p_protocol_dump(c, req->rc);
 951                 goto error;
 952         }
 953
 954         p9_debug(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
 955         if (!strncmp(version, "9P2000.L", 8))
 956                 c->proto_version = p9_proto_2000L;
 957         else if (!strncmp(version, "9P2000.u", 8))
 958                 c->proto_version = p9_proto_2000u;
 959         else if (!strncmp(version, "9P2000", 6))
 960                 c->proto_version = p9_proto_legacy;
 961         else {
 962                 err = -EREMOTEIO;
 963                 goto error;
 964         }
 965
 966         if (msize < c->msize)
 967                 c->msize = msize;
 968
 969 error:
 970         kfree(version);
 971         p9_free_req(c, req);
 972
 973         return err;
 974 }
 975
 976 struct p9_client *p9_client_create(const char *dev_name, char *options)
 977 {
 978         int err;
 979         struct p9_client *clnt;
 980
 981         err = 0;
 982         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
 983         if (!clnt)
 984                 return ERR_PTR(-ENOMEM);
 985
 986         clnt->trans_mod = NULL;
 987         clnt->trans = NULL;
 988         spin_lock_init(&clnt->lock);
 989         INIT_LIST_HEAD(&clnt->fidlist);
 990
 991         err = p9_tag_init(clnt);
 992         if (err < 0)
 993                 goto free_client;
 994
 995         err = parse_opts(options, clnt);
 996         if (err < 0)
 997                 goto destroy_tagpool;
 998
 999         if (!clnt->trans_mod)
1000                 clnt->trans_mod = v9fs_get_default_trans();
1001
1002         if (clnt->trans_mod == NULL) {
1003                 err = -EPROTONOSUPPORT;
1004                 p9_debug(P9_DEBUG_ERROR,
1005                          "No transport defined or default transport\n");
1006                 goto destroy_tagpool;
1007         }
1008
1009         clnt->fidpool = p9_idpool_create();
1010         if (IS_ERR(clnt->fidpool)) {
1011                 err = PTR_ERR(clnt->fidpool);
1012                 goto put_trans;
1013         }
1014
1015         p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
1016                  clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
1017
1018         err = clnt->trans_mod->create(clnt, dev_name, options);
1019         if (err)
1020                 goto destroy_fidpool;
1021
1022         if (clnt->msize > clnt->trans_mod->maxsize)
1023                 clnt->msize = clnt->trans_mod->maxsize;
1024
1025         err = p9_client_version(clnt);
1026         if (err)
1027                 goto close_trans;
1028
1029         return clnt;
1030
1031 close_trans:
1032         clnt->trans_mod->close(clnt);
1033 destroy_fidpool:
1034         p9_idpool_destroy(clnt->fidpool);
1035 put_trans:
1036         v9fs_put_trans(clnt->trans_mod);
1037 destroy_tagpool:
1038         p9_idpool_destroy(clnt->tagpool);
1039 free_client:
1040         kfree(clnt);
1041         return ERR_PTR(err);
1042 }
1043 EXPORT_SYMBOL(p9_client_create);
1044
1045 void p9_client_destroy(struct p9_client *clnt)
1046 {
1047         struct p9_fid *fid, *fidptr;
1048
1049         p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt);
1050
1051         if (clnt->trans_mod)
1052                 clnt->trans_mod->close(clnt);
1053
1054         v9fs_put_trans(clnt->trans_mod);
1055
1056         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist) {
1057                 pr_info("Found fid %d not clunked\n", fid->fid);
1058                 p9_fid_destroy(fid);
1059         }
1060
1061         if (clnt->fidpool)
1062                 p9_idpool_destroy(clnt->fidpool);
1063
1064         p9_tag_cleanup(clnt);
1065
1066         kfree(clnt);
1067 }
1068 EXPORT_SYMBOL(p9_client_destroy);
1069
1070 void p9_client_disconnect(struct p9_client *clnt)
1071 {
1072         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1073         clnt->status = Disconnected;
1074 }
1075 EXPORT_SYMBOL(p9_client_disconnect);
1076
1077 void p9_client_begin_disconnect(struct p9_client *clnt)
1078 {
1079         p9_debug(P9_DEBUG_9P, "clnt %p\n", clnt);
1080         clnt->status = BeginDisconnect;
1081 }
1082 EXPORT_SYMBOL(p9_client_begin_disconnect);
1083
1084 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
1085         char *uname, kuid_t n_uname, char *aname)
1086 {
1087         int err = 0;
1088         struct p9_req_t *req;
1089         struct p9_fid *fid;
1090         struct p9_qid qid;
1091
1092
1093         p9_debug(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
1094                  afid ? afid->fid : -1, uname, aname);
1095         fid = p9_fid_create(clnt);
1096         if (IS_ERR(fid)) {
1097                 err = PTR_ERR(fid);
1098                 fid = NULL;
1099                 goto error;
1100         }
1101
1102         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?u", fid->fid,
1103                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
1104         if (IS_ERR(req)) {
1105                 err = PTR_ERR(req);
1106                 goto error;
1107         }
1108
1109         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
1110         if (err) {
1111                 trace_9p_protocol_dump(clnt, req->rc);
1112                 p9_free_req(clnt, req);
1113                 goto error;
1114         }
1115
1116         p9_debug(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
1117                  qid.type, (unsigned long long)qid.path, qid.version);
1118
1119         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
1120
1121         p9_free_req(clnt, req);
1122         return fid;
1123
1124 error:
1125         if (fid)
1126                 p9_fid_destroy(fid);
1127         return ERR_PTR(err);
1128 }
1129 EXPORT_SYMBOL(p9_client_attach);
1130
1131 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
1132                 char **wnames, int clone)
1133 {
1134         int err;
1135         struct p9_client *clnt;
1136         struct p9_fid *fid;
1137         struct p9_qid *wqids;
1138         struct p9_req_t *req;
1139         uint16_t nwqids, count;
1140
1141         err = 0;
1142         wqids = NULL;
1143         clnt = oldfid->clnt;
1144         if (clone) {
1145                 fid = p9_fid_create(clnt);
1146                 if (IS_ERR(fid)) {
1147                         err = PTR_ERR(fid);
1148                         fid = NULL;
1149                         goto error;
1150                 }
1151
1152                 fid->uid = oldfid->uid;
1153         } else
1154                 fid = oldfid;
1155
1156
1157         p9_debug(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %ud wname[0] %s\n",
1158                  oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
1159
1160         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
1161                                                                 nwname, wnames);
1162         if (IS_ERR(req)) {
1163                 err = PTR_ERR(req);
1164                 goto error;
1165         }
1166
1167         err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
1168         if (err) {
1169                 trace_9p_protocol_dump(clnt, req->rc);
1170                 p9_free_req(clnt, req);
1171                 goto clunk_fid;
1172         }
1173         p9_free_req(clnt, req);
1174
1175         p9_debug(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
1176
1177         if (nwqids != nwname) {
1178                 err = -ENOENT;
1179                 goto clunk_fid;
1180         }
1181
1182         for (count = 0; count < nwqids; count++)
1183                 p9_debug(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
1184                         count, wqids[count].type,
1185                         (unsigned long long)wqids[count].path,
1186                         wqids[count].version);
1187
1188         if (nwname)
1189                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
1190         else
1191                 fid->qid = oldfid->qid;
1192
1193         kfree(wqids);
1194         return fid;
1195
1196 clunk_fid:
1197         kfree(wqids);
1198         p9_client_clunk(fid);
1199         fid = NULL;
1200
1201 error:
1202         if (fid && (fid != oldfid))
1203                 p9_fid_destroy(fid);
1204
1205         return ERR_PTR(err);
1206 }
1207 EXPORT_SYMBOL(p9_client_walk);
1208
1209 int p9_client_open(struct p9_fid *fid, int mode)
1210 {
1211         int err;
1212         struct p9_client *clnt;
1213         struct p9_req_t *req;
1214         struct p9_qid qid;
1215         int iounit;
1216
1217         clnt = fid->clnt;
1218         p9_debug(P9_DEBUG_9P, ">>> %s fid %d mode %d\n",
1219                 p9_is_proto_dotl(clnt) ? "TLOPEN" : "TOPEN", fid->fid, mode);
1220         err = 0;
1221
1222         if (fid->mode != -1)
1223                 return -EINVAL;
1224
1225         if (p9_is_proto_dotl(clnt))
1226                 req = p9_client_rpc(clnt, P9_TLOPEN, "dd", fid->fid, mode);
1227         else
1228                 req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1229         if (IS_ERR(req)) {
1230                 err = PTR_ERR(req);
1231                 goto error;
1232         }
1233
1234         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1235         if (err) {
1236                 trace_9p_protocol_dump(clnt, req->rc);
1237                 goto free_and_error;
1238         }
1239
1240         p9_debug(P9_DEBUG_9P, "<<< %s qid %x.%llx.%x iounit %x\n",
1241                 p9_is_proto_dotl(clnt) ? "RLOPEN" : "ROPEN",  qid.type,
1242                 (unsigned long long)qid.path, qid.version, iounit);
1243
1244         fid->mode = mode;
1245         fid->iounit = iounit;
1246
1247 free_and_error:
1248         p9_free_req(clnt, req);
1249 error:
1250         return err;
1251 }
1252 EXPORT_SYMBOL(p9_client_open);
1253
1254 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
1255                 kgid_t gid, struct p9_qid *qid)
1256 {
1257         int err = 0;
1258         struct p9_client *clnt;
1259         struct p9_req_t *req;
1260         int iounit;
1261
1262         p9_debug(P9_DEBUG_9P,
1263                         ">>> TLCREATE fid %d name %s flags %d mode %d gid %d\n",
1264                         ofid->fid, name, flags, mode,
1265                         from_kgid(&init_user_ns, gid));
1266         clnt = ofid->clnt;
1267
1268         if (ofid->mode != -1)
1269                 return -EINVAL;
1270
1271         req = p9_client_rpc(clnt, P9_TLCREATE, "dsddg", ofid->fid, name, flags,
1272                         mode, gid);
1273         if (IS_ERR(req)) {
1274                 err = PTR_ERR(req);
1275                 goto error;
1276         }
1277
1278         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", qid, &iounit);
1279         if (err) {
1280                 trace_9p_protocol_dump(clnt, req->rc);
1281                 goto free_and_error;
1282         }
1283
1284         p9_debug(P9_DEBUG_9P, "<<< RLCREATE qid %x.%llx.%x iounit %x\n",
1285                         qid->type,
1286                         (unsigned long long)qid->path,
1287                         qid->version, iounit);
1288
1289         ofid->mode = mode;
1290         ofid->iounit = iounit;
1291
1292 free_and_error:
1293         p9_free_req(clnt, req);
1294 error:
1295         return err;
1296 }
1297 EXPORT_SYMBOL(p9_client_create_dotl);
1298
1299 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1300                      char *extension)
1301 {
1302         int err;
1303         struct p9_client *clnt;
1304         struct p9_req_t *req;
1305         struct p9_qid qid;
1306         int iounit;
1307
1308         p9_debug(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1309                                                 fid->fid, name, perm, mode);
1310         err = 0;
1311         clnt = fid->clnt;
1312
1313         if (fid->mode != -1)
1314                 return -EINVAL;
1315
1316         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1317                                 mode, extension);
1318         if (IS_ERR(req)) {
1319                 err = PTR_ERR(req);
1320                 goto error;
1321         }
1322
1323         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1324         if (err) {
1325                 trace_9p_protocol_dump(clnt, req->rc);
1326                 goto free_and_error;
1327         }
1328
1329         p9_debug(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1330                                 qid.type,
1331                                 (unsigned long long)qid.path,
1332                                 qid.version, iounit);
1333
1334         fid->mode = mode;
1335         fid->iounit = iounit;
1336
1337 free_and_error:
1338         p9_free_req(clnt, req);
1339 error:
1340         return err;
1341 }
1342 EXPORT_SYMBOL(p9_client_fcreate);
1343
1344 int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, kgid_t gid,
1345                 struct p9_qid *qid)
1346 {
1347         int err = 0;
1348         struct p9_client *clnt;
1349         struct p9_req_t *req;
1350
1351         p9_debug(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s  symtgt %s\n",
1352                         dfid->fid, name, symtgt);
1353         clnt = dfid->clnt;
1354
1355         req = p9_client_rpc(clnt, P9_TSYMLINK, "dssg", dfid->fid, name, symtgt,
1356                         gid);
1357         if (IS_ERR(req)) {
1358                 err = PTR_ERR(req);
1359                 goto error;
1360         }
1361
1362         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
1363         if (err) {
1364                 trace_9p_protocol_dump(clnt, req->rc);
1365                 goto free_and_error;
1366         }
1367
1368         p9_debug(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
1369                         qid->type, (unsigned long long)qid->path, qid->version);
1370
1371 free_and_error:
1372         p9_free_req(clnt, req);
1373 error:
1374         return err;
1375 }
1376 EXPORT_SYMBOL(p9_client_symlink);
1377
1378 int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
1379 {
1380         struct p9_client *clnt;
1381         struct p9_req_t *req;
1382
1383         p9_debug(P9_DEBUG_9P, ">>> TLINK dfid %d oldfid %d newname %s\n",
1384                         dfid->fid, oldfid->fid, newname);
1385         clnt = dfid->clnt;
1386         req = p9_client_rpc(clnt, P9_TLINK, "dds", dfid->fid, oldfid->fid,
1387                         newname);
1388         if (IS_ERR(req))
1389                 return PTR_ERR(req);
1390
1391         p9_debug(P9_DEBUG_9P, "<<< RLINK\n");
1392         p9_free_req(clnt, req);
1393         return 0;
1394 }
1395 EXPORT_SYMBOL(p9_client_link);
1396
1397 int p9_client_fsync(struct p9_fid *fid, int datasync)
1398 {
1399         int err;
1400         struct p9_client *clnt;
1401         struct p9_req_t *req;
1402
1403         p9_debug(P9_DEBUG_9P, ">>> TFSYNC fid %d datasync:%d\n",
1404                         fid->fid, datasync);
1405         err = 0;
1406         clnt = fid->clnt;
1407
1408         req = p9_client_rpc(clnt, P9_TFSYNC, "dd", fid->fid, datasync);
1409         if (IS_ERR(req)) {
1410                 err = PTR_ERR(req);
1411                 goto error;
1412         }
1413
1414         p9_debug(P9_DEBUG_9P, "<<< RFSYNC fid %d\n", fid->fid);
1415
1416         p9_free_req(clnt, req);
1417
1418 error:
1419         return err;
1420 }
1421 EXPORT_SYMBOL(p9_client_fsync);
1422
1423 int p9_client_clunk(struct p9_fid *fid)
1424 {
1425         int err;
1426         struct p9_client *clnt;
1427         struct p9_req_t *req;
1428         int retries = 0;
1429
1430         if (!fid) {
1431                 pr_warn("%s (%d): Trying to clunk with NULL fid\n",
1432                         __func__, task_pid_nr(current));
1433                 dump_stack();
1434                 return 0;
1435         }
1436
1437 again:
1438         p9_debug(P9_DEBUG_9P, ">>> TCLUNK fid %d (try %d)\n", fid->fid,
1439                                                                 retries);
1440         err = 0;
1441         clnt = fid->clnt;
1442
1443         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1444         if (IS_ERR(req)) {
1445                 err = PTR_ERR(req);
1446                 goto error;
1447         }
1448
1449         p9_debug(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1450
1451         p9_free_req(clnt, req);
1452 error:
1453         /*
1454          * Fid is not valid even after a failed clunk
1455          * If interrupted, retry once then give up and
1456          * leak fid until umount.
1457          */
1458         if (err == -ERESTARTSYS) {
1459                 if (retries++ == 0)
1460                         goto again;
1461         } else
1462                 p9_fid_destroy(fid);
1463         return err;
1464 }
1465 EXPORT_SYMBOL(p9_client_clunk);
1466
1467 int p9_client_remove(struct p9_fid *fid)
1468 {
1469         int err;
1470         struct p9_client *clnt;
1471         struct p9_req_t *req;
1472
1473         p9_debug(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1474         err = 0;
1475         clnt = fid->clnt;
1476
1477         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1478         if (IS_ERR(req)) {
1479                 err = PTR_ERR(req);
1480                 goto error;
1481         }
1482
1483         p9_debug(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1484
1485         p9_free_req(clnt, req);
1486 error:
1487         if (err == -ERESTARTSYS)
1488                 p9_client_clunk(fid);
1489         else
1490                 p9_fid_destroy(fid);
1491         return err;
1492 }
1493 EXPORT_SYMBOL(p9_client_remove);
1494
1495 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags)
1496 {
1497         int err = 0;
1498         struct p9_req_t *req;
1499         struct p9_client *clnt;
1500
1501         p9_debug(P9_DEBUG_9P, ">>> TUNLINKAT fid %d %s %d\n",
1502                    dfid->fid, name, flags);
1503
1504         clnt = dfid->clnt;
1505         req = p9_client_rpc(clnt, P9_TUNLINKAT, "dsd", dfid->fid, name, flags);
1506         if (IS_ERR(req)) {
1507                 err = PTR_ERR(req);
1508                 goto error;
1509         }
1510         p9_debug(P9_DEBUG_9P, "<<< RUNLINKAT fid %d %s\n", dfid->fid, name);
1511
1512         p9_free_req(clnt, req);
1513 error:
1514         return err;
1515 }
1516 EXPORT_SYMBOL(p9_client_unlinkat);
1517
1518 int
1519 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1520                                                                 u32 count)
1521 {
1522         char *dataptr;
1523         int kernel_buf = 0;
1524         struct p9_req_t *req;
1525         struct p9_client *clnt;
1526         int err, rsize, non_zc = 0;
1527
1528
1529         p9_debug(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n",
1530                    fid->fid, (unsigned long long) offset, count);
1531         err = 0;
1532         clnt = fid->clnt;
1533
1534         rsize = fid->iounit;
1535         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1536                 rsize = clnt->msize - P9_IOHDRSZ;
1537
1538         if (count < rsize)
1539                 rsize = count;
1540
1541         /* Don't bother zerocopy for small IO (< 1024) */
1542         if (clnt->trans_mod->zc_request && rsize > 1024) {
1543                 char *indata;
1544                 if (data) {
1545                         kernel_buf = 1;
1546                         indata = data;
1547                 } else
1548                         indata = (__force char *)udata;
1549                 /*
1550                  * response header len is 11
1551                  * PDU Header(7) + IO Size (4)
1552                  */
1553                 req = p9_client_zc_rpc(clnt, P9_TREAD, indata, NULL, rsize, 0,
1554                                        11, kernel_buf, "dqd", fid->fid,
1555                                        offset, rsize);
1556         } else {
1557                 non_zc = 1;
1558                 req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset,
1559                                     rsize);
1560         }
1561         if (IS_ERR(req)) {
1562                 err = PTR_ERR(req);
1563                 goto error;
1564         }
1565
1566         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1567         if (err) {
1568                 trace_9p_protocol_dump(clnt, req->rc);
1569                 goto free_and_error;
1570         }
1571
1572         p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1573
1574         if (non_zc) {
1575                 if (data) {
1576                         memmove(data, dataptr, count);
1577                 } else {
1578                         err = copy_to_user(udata, dataptr, count);
1579                         if (err) {
1580                                 err = -EFAULT;
1581                                 goto free_and_error;
1582                         }
1583                 }
1584         }
1585         p9_free_req(clnt, req);
1586         return count;
1587
1588 free_and_error:
1589         p9_free_req(clnt, req);
1590 error:
1591         return err;
1592 }
1593 EXPORT_SYMBOL(p9_client_read);
1594
1595 int
1596 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1597                                                         u64 offset, u32 count)
1598 {
1599         int err, rsize;
1600         int kernel_buf = 0;
1601         struct p9_client *clnt;
1602         struct p9_req_t *req;
1603
1604         p9_debug(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1605                                 fid->fid, (unsigned long long) offset, count);
1606         err = 0;
1607         clnt = fid->clnt;
1608
1609         rsize = fid->iounit;
1610         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1611                 rsize = clnt->msize - P9_IOHDRSZ;
1612
1613         if (count < rsize)
1614                 rsize = count;
1615
1616         /* Don't bother zerocopy for small IO (< 1024) */
1617         if (clnt->trans_mod->zc_request && rsize > 1024) {
1618                 char *odata;
1619                 if (data) {
1620                         kernel_buf = 1;
1621                         odata = data;
1622                 } else
1623                         odata = (char *)udata;
1624                 req = p9_client_zc_rpc(clnt, P9_TWRITE, NULL, odata, 0, rsize,
1625                                        P9_ZC_HDR_SZ, kernel_buf, "dqd",
1626                                        fid->fid, offset, rsize);
1627         } else {
1628                 if (data)
1629                         req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid,
1630                                             offset, rsize, data);
1631                 else
1632                         req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid,
1633                                             offset, rsize, udata);
1634         }
1635         if (IS_ERR(req)) {
1636                 err = PTR_ERR(req);
1637                 goto error;
1638         }
1639
1640         err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1641         if (err) {
1642                 trace_9p_protocol_dump(clnt, req->rc);
1643                 goto free_and_error;
1644         }
1645
1646         p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1647
1648         p9_free_req(clnt, req);
1649         return count;
1650
1651 free_and_error:
1652         p9_free_req(clnt, req);
1653 error:
1654         return err;
1655 }
1656 EXPORT_SYMBOL(p9_client_write);
1657
1658 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1659 {
1660         int err;
1661         struct p9_client *clnt;
1662         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1663         struct p9_req_t *req;
1664         u16 ignored;
1665
1666         p9_debug(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1667
1668         if (!ret)
1669                 return ERR_PTR(-ENOMEM);
1670
1671         err = 0;
1672         clnt = fid->clnt;
1673
1674         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1675         if (IS_ERR(req)) {
1676                 err = PTR_ERR(req);
1677                 goto error;
1678         }
1679
1680         err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1681         if (err) {
1682                 trace_9p_protocol_dump(clnt, req->rc);
1683                 p9_free_req(clnt, req);
1684                 goto error;
1685         }
1686
1687         p9_debug(P9_DEBUG_9P,
1688                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1689                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1690                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1691                 "<<<    uid=%d gid=%d n_muid=%d\n",
1692                 ret->size, ret->type, ret->dev, ret->qid.type,
1693                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1694                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1695                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1696                 from_kuid(&init_user_ns, ret->n_uid),
1697                 from_kgid(&init_user_ns, ret->n_gid),
1698                 from_kuid(&init_user_ns, ret->n_muid));
1699
1700         p9_free_req(clnt, req);
1701         return ret;
1702
1703 error:
1704         kfree(ret);
1705         return ERR_PTR(err);
1706 }
1707 EXPORT_SYMBOL(p9_client_stat);
1708
1709 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
1710                                                         u64 request_mask)
1711 {
1712         int err;
1713         struct p9_client *clnt;
1714         struct p9_stat_dotl *ret = kmalloc(sizeof(struct p9_stat_dotl),
1715                                                                 GFP_KERNEL);
1716         struct p9_req_t *req;
1717
1718         p9_debug(P9_DEBUG_9P, ">>> TGETATTR fid %d, request_mask %lld\n",
1719                                                         fid->fid, request_mask);
1720
1721         if (!ret)
1722                 return ERR_PTR(-ENOMEM);
1723
1724         err = 0;
1725         clnt = fid->clnt;
1726
1727         req = p9_client_rpc(clnt, P9_TGETATTR, "dq", fid->fid, request_mask);
1728         if (IS_ERR(req)) {
1729                 err = PTR_ERR(req);
1730                 goto error;
1731         }
1732
1733         err = p9pdu_readf(req->rc, clnt->proto_version, "A", ret);
1734         if (err) {
1735                 trace_9p_protocol_dump(clnt, req->rc);
1736                 p9_free_req(clnt, req);
1737                 goto error;
1738         }
1739
1740         p9_debug(P9_DEBUG_9P,
1741                 "<<< RGETATTR st_result_mask=%lld\n"
1742                 "<<< qid=%x.%llx.%x\n"
1743                 "<<< st_mode=%8.8x st_nlink=%llu\n"
1744                 "<<< st_uid=%d st_gid=%d\n"
1745                 "<<< st_rdev=%llx st_size=%llx st_blksize=%llu st_blocks=%llu\n"
1746                 "<<< st_atime_sec=%lld st_atime_nsec=%lld\n"
1747                 "<<< st_mtime_sec=%lld st_mtime_nsec=%lld\n"
1748                 "<<< st_ctime_sec=%lld st_ctime_nsec=%lld\n"
1749                 "<<< st_btime_sec=%lld st_btime_nsec=%lld\n"
1750                 "<<< st_gen=%lld st_data_version=%lld",
1751                 ret->st_result_mask, ret->qid.type, ret->qid.path,
1752                 ret->qid.version, ret->st_mode, ret->st_nlink,
1753                 from_kuid(&init_user_ns, ret->st_uid),
1754                 from_kgid(&init_user_ns, ret->st_gid),
1755                 ret->st_rdev, ret->st_size, ret->st_blksize,
1756                 ret->st_blocks, ret->st_atime_sec, ret->st_atime_nsec,
1757                 ret->st_mtime_sec, ret->st_mtime_nsec, ret->st_ctime_sec,
1758                 ret->st_ctime_nsec, ret->st_btime_sec, ret->st_btime_nsec,
1759                 ret->st_gen, ret->st_data_version);
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_getattr_dotl);
1769
1770 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1771 {
1772         int ret;
1773
1774         /* NOTE: size shouldn't include its own length */
1775         /* size[2] type[2] dev[4] qid[13] */
1776         /* mode[4] atime[4] mtime[4] length[8]*/
1777         /* name[s] uid[s] gid[s] muid[s] */
1778         ret = 2+4+13+4+4+4+8+2+2+2+2;
1779
1780         if (wst->name)
1781                 ret += strlen(wst->name);
1782         if (wst->uid)
1783                 ret += strlen(wst->uid);
1784         if (wst->gid)
1785                 ret += strlen(wst->gid);
1786         if (wst->muid)
1787                 ret += strlen(wst->muid);
1788
1789         if ((proto_version == p9_proto_2000u) ||
1790                 (proto_version == p9_proto_2000L)) {
1791                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1792                 if (wst->extension)
1793                         ret += strlen(wst->extension);
1794         }
1795
1796         return ret;
1797 }
1798
1799 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1800 {
1801         int err;
1802         struct p9_req_t *req;
1803         struct p9_client *clnt;
1804
1805         err = 0;
1806         clnt = fid->clnt;
1807         wst->size = p9_client_statsize(wst, clnt->proto_version);
1808         p9_debug(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1809         p9_debug(P9_DEBUG_9P,
1810                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1811                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1812                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1813                 "     uid=%d gid=%d n_muid=%d\n",
1814                 wst->size, wst->type, wst->dev, wst->qid.type,
1815                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1816                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1817                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1818                 from_kuid(&init_user_ns, wst->n_uid),
1819                 from_kgid(&init_user_ns, wst->n_gid),
1820                 from_kuid(&init_user_ns, wst->n_muid));
1821
1822         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1823         if (IS_ERR(req)) {
1824                 err = PTR_ERR(req);
1825                 goto error;
1826         }
1827
1828         p9_debug(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1829
1830         p9_free_req(clnt, req);
1831 error:
1832         return err;
1833 }
1834 EXPORT_SYMBOL(p9_client_wstat);
1835
1836 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *p9attr)
1837 {
1838         int err;
1839         struct p9_req_t *req;
1840         struct p9_client *clnt;
1841
1842         err = 0;
1843         clnt = fid->clnt;
1844         p9_debug(P9_DEBUG_9P, ">>> TSETATTR fid %d\n", fid->fid);
1845         p9_debug(P9_DEBUG_9P,
1846                 "    valid=%x mode=%x uid=%d gid=%d size=%lld\n"
1847                 "    atime_sec=%lld atime_nsec=%lld\n"
1848                 "    mtime_sec=%lld mtime_nsec=%lld\n",
1849                 p9attr->valid, p9attr->mode,
1850                 from_kuid(&init_user_ns, p9attr->uid),
1851                 from_kgid(&init_user_ns, p9attr->gid),
1852                 p9attr->size, p9attr->atime_sec, p9attr->atime_nsec,
1853                 p9attr->mtime_sec, p9attr->mtime_nsec);
1854
1855         req = p9_client_rpc(clnt, P9_TSETATTR, "dI", fid->fid, p9attr);
1856
1857         if (IS_ERR(req)) {
1858                 err = PTR_ERR(req);
1859                 goto error;
1860         }
1861         p9_debug(P9_DEBUG_9P, "<<< RSETATTR fid %d\n", fid->fid);
1862         p9_free_req(clnt, req);
1863 error:
1864         return err;
1865 }
1866 EXPORT_SYMBOL(p9_client_setattr);
1867
1868 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb)
1869 {
1870         int err;
1871         struct p9_req_t *req;
1872         struct p9_client *clnt;
1873
1874         err = 0;
1875         clnt = fid->clnt;
1876
1877         p9_debug(P9_DEBUG_9P, ">>> TSTATFS fid %d\n", fid->fid);
1878
1879         req = p9_client_rpc(clnt, P9_TSTATFS, "d", fid->fid);
1880         if (IS_ERR(req)) {
1881                 err = PTR_ERR(req);
1882                 goto error;
1883         }
1884
1885         err = p9pdu_readf(req->rc, clnt->proto_version, "ddqqqqqqd", &sb->type,
1886                 &sb->bsize, &sb->blocks, &sb->bfree, &sb->bavail,
1887                 &sb->files, &sb->ffree, &sb->fsid, &sb->namelen);
1888         if (err) {
1889                 trace_9p_protocol_dump(clnt, req->rc);
1890                 p9_free_req(clnt, req);
1891                 goto error;
1892         }
1893
1894         p9_debug(P9_DEBUG_9P, "<<< RSTATFS fid %d type 0x%lx bsize %ld "
1895                 "blocks %llu bfree %llu bavail %llu files %llu ffree %llu "
1896                 "fsid %llu namelen %ld\n",
1897                 fid->fid, (long unsigned int)sb->type, (long int)sb->bsize,
1898                 sb->blocks, sb->bfree, sb->bavail, sb->files,  sb->ffree,
1899                 sb->fsid, (long int)sb->namelen);
1900
1901         p9_free_req(clnt, req);
1902 error:
1903         return err;
1904 }
1905 EXPORT_SYMBOL(p9_client_statfs);
1906
1907 int p9_client_rename(struct p9_fid *fid,
1908                      struct p9_fid *newdirfid, const char *name)
1909 {
1910         int err;
1911         struct p9_req_t *req;
1912         struct p9_client *clnt;
1913
1914         err = 0;
1915         clnt = fid->clnt;
1916
1917         p9_debug(P9_DEBUG_9P, ">>> TRENAME fid %d newdirfid %d name %s\n",
1918                         fid->fid, newdirfid->fid, name);
1919
1920         req = p9_client_rpc(clnt, P9_TRENAME, "dds", fid->fid,
1921                         newdirfid->fid, name);
1922         if (IS_ERR(req)) {
1923                 err = PTR_ERR(req);
1924                 goto error;
1925         }
1926
1927         p9_debug(P9_DEBUG_9P, "<<< RRENAME fid %d\n", fid->fid);
1928
1929         p9_free_req(clnt, req);
1930 error:
1931         return err;
1932 }
1933 EXPORT_SYMBOL(p9_client_rename);
1934
1935 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
1936                        struct p9_fid *newdirfid, const char *new_name)
1937 {
1938         int err;
1939         struct p9_req_t *req;
1940         struct p9_client *clnt;
1941
1942         err = 0;
1943         clnt = olddirfid->clnt;
1944
1945         p9_debug(P9_DEBUG_9P, ">>> TRENAMEAT olddirfid %d old name %s"
1946                    " newdirfid %d new name %s\n", olddirfid->fid, old_name,
1947                    newdirfid->fid, new_name);
1948
1949         req = p9_client_rpc(clnt, P9_TRENAMEAT, "dsds", olddirfid->fid,
1950                             old_name, newdirfid->fid, new_name);
1951         if (IS_ERR(req)) {
1952                 err = PTR_ERR(req);
1953                 goto error;
1954         }
1955
1956         p9_debug(P9_DEBUG_9P, "<<< RRENAMEAT newdirfid %d new name %s\n",
1957                    newdirfid->fid, new_name);
1958
1959         p9_free_req(clnt, req);
1960 error:
1961         return err;
1962 }
1963 EXPORT_SYMBOL(p9_client_renameat);
1964
1965 /*
1966  * An xattrwalk without @attr_name gives the fid for the lisxattr namespace
1967  */
1968 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid,
1969                                 const char *attr_name, u64 *attr_size)
1970 {
1971         int err;
1972         struct p9_req_t *req;
1973         struct p9_client *clnt;
1974         struct p9_fid *attr_fid;
1975
1976         err = 0;
1977         clnt = file_fid->clnt;
1978         attr_fid = p9_fid_create(clnt);
1979         if (IS_ERR(attr_fid)) {
1980                 err = PTR_ERR(attr_fid);
1981                 attr_fid = NULL;
1982                 goto error;
1983         }
1984         p9_debug(P9_DEBUG_9P,
1985                 ">>> TXATTRWALK file_fid %d, attr_fid %d name %s\n",
1986                 file_fid->fid, attr_fid->fid, attr_name);
1987
1988         req = p9_client_rpc(clnt, P9_TXATTRWALK, "dds",
1989                         file_fid->fid, attr_fid->fid, attr_name);
1990         if (IS_ERR(req)) {
1991                 err = PTR_ERR(req);
1992                 goto error;
1993         }
1994         err = p9pdu_readf(req->rc, clnt->proto_version, "q", attr_size);
1995         if (err) {
1996                 trace_9p_protocol_dump(clnt, req->rc);
1997                 p9_free_req(clnt, req);
1998                 goto clunk_fid;
1999         }
2000         p9_free_req(clnt, req);
2001         p9_debug(P9_DEBUG_9P, "<<<  RXATTRWALK fid %d size %llu\n",
2002                 attr_fid->fid, *attr_size);
2003         return attr_fid;
2004 clunk_fid:
2005         p9_client_clunk(attr_fid);
2006         attr_fid = NULL;
2007 error:
2008         if (attr_fid && (attr_fid != file_fid))
2009                 p9_fid_destroy(attr_fid);
2010
2011         return ERR_PTR(err);
2012 }
2013 EXPORT_SYMBOL_GPL(p9_client_xattrwalk);
2014
2015 int p9_client_xattrcreate(struct p9_fid *fid, const char *name,
2016                         u64 attr_size, int flags)
2017 {
2018         int err;
2019         struct p9_req_t *req;
2020         struct p9_client *clnt;
2021
2022         p9_debug(P9_DEBUG_9P,
2023                 ">>> TXATTRCREATE fid %d name  %s size %lld flag %d\n",
2024                 fid->fid, name, (long long)attr_size, flags);
2025         err = 0;
2026         clnt = fid->clnt;
2027         req = p9_client_rpc(clnt, P9_TXATTRCREATE, "dsqd",
2028                         fid->fid, name, attr_size, flags);
2029         if (IS_ERR(req)) {
2030                 err = PTR_ERR(req);
2031                 goto error;
2032         }
2033         p9_debug(P9_DEBUG_9P, "<<< RXATTRCREATE fid %d\n", fid->fid);
2034         p9_free_req(clnt, req);
2035 error:
2036         return err;
2037 }
2038 EXPORT_SYMBOL_GPL(p9_client_xattrcreate);
2039
2040 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset)
2041 {
2042         int err, rsize, non_zc = 0;
2043         struct p9_client *clnt;
2044         struct p9_req_t *req;
2045         char *dataptr;
2046
2047         p9_debug(P9_DEBUG_9P, ">>> TREADDIR fid %d offset %llu count %d\n",
2048                                 fid->fid, (unsigned long long) offset, count);
2049
2050         err = 0;
2051         clnt = fid->clnt;
2052
2053         rsize = fid->iounit;
2054         if (!rsize || rsize > clnt->msize-P9_READDIRHDRSZ)
2055                 rsize = clnt->msize - P9_READDIRHDRSZ;
2056
2057         if (count < rsize)
2058                 rsize = count;
2059
2060         /* Don't bother zerocopy for small IO (< 1024) */
2061         if (clnt->trans_mod->zc_request && rsize > 1024) {
2062                 /*
2063                  * response header len is 11
2064                  * PDU Header(7) + IO Size (4)
2065                  */
2066                 req = p9_client_zc_rpc(clnt, P9_TREADDIR, data, NULL, rsize, 0,
2067                                        11, 1, "dqd", fid->fid, offset, rsize);
2068         } else {
2069                 non_zc = 1;
2070                 req = p9_client_rpc(clnt, P9_TREADDIR, "dqd", fid->fid,
2071                                     offset, rsize);
2072         }
2073         if (IS_ERR(req)) {
2074                 err = PTR_ERR(req);
2075                 goto error;
2076         }
2077
2078         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
2079         if (err) {
2080                 trace_9p_protocol_dump(clnt, req->rc);
2081                 goto free_and_error;
2082         }
2083
2084         p9_debug(P9_DEBUG_9P, "<<< RREADDIR count %d\n", count);
2085
2086         if (non_zc)
2087                 memmove(data, dataptr, count);
2088
2089         p9_free_req(clnt, req);
2090         return count;
2091
2092 free_and_error:
2093         p9_free_req(clnt, req);
2094 error:
2095         return err;
2096 }
2097 EXPORT_SYMBOL(p9_client_readdir);
2098
2099 int p9_client_mknod_dotl(struct p9_fid *fid, char *name, int mode,
2100                         dev_t rdev, kgid_t gid, struct p9_qid *qid)
2101 {
2102         int err;
2103         struct p9_client *clnt;
2104         struct p9_req_t *req;
2105
2106         err = 0;
2107         clnt = fid->clnt;
2108         p9_debug(P9_DEBUG_9P, ">>> TMKNOD fid %d name %s mode %d major %d "
2109                 "minor %d\n", fid->fid, name, mode, MAJOR(rdev), MINOR(rdev));
2110         req = p9_client_rpc(clnt, P9_TMKNOD, "dsdddg", fid->fid, name, mode,
2111                 MAJOR(rdev), MINOR(rdev), gid);
2112         if (IS_ERR(req))
2113                 return PTR_ERR(req);
2114
2115         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2116         if (err) {
2117                 trace_9p_protocol_dump(clnt, req->rc);
2118                 goto error;
2119         }
2120         p9_debug(P9_DEBUG_9P, "<<< RMKNOD qid %x.%llx.%x\n", qid->type,
2121                                 (unsigned long long)qid->path, qid->version);
2122
2123 error:
2124         p9_free_req(clnt, req);
2125         return err;
2126
2127 }
2128 EXPORT_SYMBOL(p9_client_mknod_dotl);
2129
2130 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
2131                                 kgid_t gid, struct p9_qid *qid)
2132 {
2133         int err;
2134         struct p9_client *clnt;
2135         struct p9_req_t *req;
2136
2137         err = 0;
2138         clnt = fid->clnt;
2139         p9_debug(P9_DEBUG_9P, ">>> TMKDIR fid %d name %s mode %d gid %d\n",
2140                  fid->fid, name, mode, from_kgid(&init_user_ns, gid));
2141         req = p9_client_rpc(clnt, P9_TMKDIR, "dsdg", fid->fid, name, mode,
2142                 gid);
2143         if (IS_ERR(req))
2144                 return PTR_ERR(req);
2145
2146         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
2147         if (err) {
2148                 trace_9p_protocol_dump(clnt, req->rc);
2149                 goto error;
2150         }
2151         p9_debug(P9_DEBUG_9P, "<<< RMKDIR qid %x.%llx.%x\n", qid->type,
2152                                 (unsigned long long)qid->path, qid->version);
2153
2154 error:
2155         p9_free_req(clnt, req);
2156         return err;
2157
2158 }
2159 EXPORT_SYMBOL(p9_client_mkdir_dotl);
2160
2161 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status)
2162 {
2163         int err;
2164         struct p9_client *clnt;
2165         struct p9_req_t *req;
2166
2167         err = 0;
2168         clnt = fid->clnt;
2169         p9_debug(P9_DEBUG_9P, ">>> TLOCK fid %d type %i flags %d "
2170                         "start %lld length %lld proc_id %d client_id %s\n",
2171                         fid->fid, flock->type, flock->flags, flock->start,
2172                         flock->length, flock->proc_id, flock->client_id);
2173
2174         req = p9_client_rpc(clnt, P9_TLOCK, "dbdqqds", fid->fid, flock->type,
2175                                 flock->flags, flock->start, flock->length,
2176                                         flock->proc_id, flock->client_id);
2177
2178         if (IS_ERR(req))
2179                 return PTR_ERR(req);
2180
2181         err = p9pdu_readf(req->rc, clnt->proto_version, "b", status);
2182         if (err) {
2183                 trace_9p_protocol_dump(clnt, req->rc);
2184                 goto error;
2185         }
2186         p9_debug(P9_DEBUG_9P, "<<< RLOCK status %i\n", *status);
2187 error:
2188         p9_free_req(clnt, req);
2189         return err;
2190
2191 }
2192 EXPORT_SYMBOL(p9_client_lock_dotl);
2193
2194 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *glock)
2195 {
2196         int err;
2197         struct p9_client *clnt;
2198         struct p9_req_t *req;
2199
2200         err = 0;
2201         clnt = fid->clnt;
2202         p9_debug(P9_DEBUG_9P, ">>> TGETLOCK fid %d, type %i start %lld "
2203                 "length %lld proc_id %d client_id %s\n", fid->fid, glock->type,
2204                 glock->start, glock->length, glock->proc_id, glock->client_id);
2205
2206         req = p9_client_rpc(clnt, P9_TGETLOCK, "dbqqds", fid->fid,  glock->type,
2207                 glock->start, glock->length, glock->proc_id, glock->client_id);
2208
2209         if (IS_ERR(req))
2210                 return PTR_ERR(req);
2211
2212         err = p9pdu_readf(req->rc, clnt->proto_version, "bqqds", &glock->type,
2213                         &glock->start, &glock->length, &glock->proc_id,
2214                         &glock->client_id);
2215         if (err) {
2216                 trace_9p_protocol_dump(clnt, req->rc);
2217                 goto error;
2218         }
2219         p9_debug(P9_DEBUG_9P, "<<< RGETLOCK type %i start %lld length %lld "
2220                 "proc_id %d client_id %s\n", glock->type, glock->start,
2221                 glock->length, glock->proc_id, glock->client_id);
2222 error:
2223         p9_free_req(clnt, req);
2224         return err;
2225 }
2226 EXPORT_SYMBOL(p9_client_getlock_dotl);
2227
2228 int p9_client_readlink(struct p9_fid *fid, char **target)
2229 {
2230         int err;
2231         struct p9_client *clnt;
2232         struct p9_req_t *req;
2233
2234         err = 0;
2235         clnt = fid->clnt;
2236         p9_debug(P9_DEBUG_9P, ">>> TREADLINK fid %d\n", fid->fid);
2237
2238         req = p9_client_rpc(clnt, P9_TREADLINK, "d", fid->fid);
2239         if (IS_ERR(req))
2240                 return PTR_ERR(req);
2241
2242         err = p9pdu_readf(req->rc, clnt->proto_version, "s", target);
2243         if (err) {
2244                 trace_9p_protocol_dump(clnt, req->rc);
2245                 goto error;
2246         }
2247         p9_debug(P9_DEBUG_9P, "<<< RREADLINK target %s\n", *target);
2248 error:
2249         p9_free_req(clnt, req);
2250         return err;
2251 }
2252 EXPORT_SYMBOL(p9_client_readlink);