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   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 #include <linux/module.h>
  27 #include <linux/errno.h>
  28 #include <linux/fs.h>
  29 #include <linux/poll.h>
  30 #include <linux/idr.h>
  31 #include <linux/mutex.h>
  32 #include <linux/sched.h>
  33 #include <linux/uaccess.h>
  34 #include <net/9p/9p.h>
  35 #include <linux/parser.h>
  36 #include <net/9p/client.h>
  37 #include <net/9p/transport.h>
  38 #include "protocol.h"
  39
  40 /*
  41   * Client Option Parsing (code inspired by NFS code)
  42   *  - a little lazy - parse all client options
  43   */
  44
  45 enum {
  46         Opt_msize,
  47         Opt_trans,
  48         Opt_legacy,
  49         Opt_err,
  50 };
  51
  52 static const match_table_t tokens = {
  53         {Opt_msize, "msize=%u"},
  54         {Opt_legacy, "noextend"},
  55         {Opt_trans, "trans=%s"},
  56         {Opt_err, NULL},
  57 };
  58
  59 static struct p9_req_t *
  60 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
  61
  62 /**
  63  * v9fs_parse_options - parse mount options into session structure
  64  * @options: options string passed from mount
  65  * @v9ses: existing v9fs session information
  66  *
  67  * Return 0 upon success, -ERRNO upon failure
  68  */
  69
  70 static int parse_opts(char *opts, struct p9_client *clnt)
  71 {
  72         char *options;
  73         char *p;
  74         substring_t args[MAX_OPT_ARGS];
  75         int option;
  76         int ret = 0;
  77
  78         clnt->dotu = 1;
  79         clnt->msize = 8192;
  80
  81         if (!opts)
  82                 return 0;
  83
  84         options = kstrdup(opts, GFP_KERNEL);
  85         if (!options) {
  86                 P9_DPRINTK(P9_DEBUG_ERROR,
  87                                 "failed to allocate copy of option string\n");
  88                 return -ENOMEM;
  89         }
  90
  91         while ((p = strsep(&options, ",")) != NULL) {
  92                 int token;
  93                 if (!*p)
  94                         continue;
  95                 token = match_token(p, tokens, args);
  96                 if (token < Opt_trans) {
  97                         int r = match_int(&args[0], &option);
  98                         if (r < 0) {
  99                                 P9_DPRINTK(P9_DEBUG_ERROR,
 100                                         "integer field, but no integer?\n");
 101                                 ret = r;
 102                                 continue;
 103                         }
 104                 }
 105                 switch (token) {
 106                 case Opt_msize:
 107                         clnt->msize = option;
 108                         break;
 109                 case Opt_trans:
 110                         clnt->trans_mod = v9fs_get_trans_by_name(&args[0]);
 111                         break;
 112                 case Opt_legacy:
 113                         clnt->dotu = 0;
 114                         break;
 115                 default:
 116                         continue;
 117                 }
 118         }
 119
 120         kfree(options);
 121         return ret;
 122 }
 123
 124 /**
 125  * p9_tag_alloc - lookup/allocate a request by tag
 126  * @c: client session to lookup tag within
 127  * @tag: numeric id for transaction
 128  *
 129  * this is a simple array lookup, but will grow the
 130  * request_slots as necessary to accomodate transaction
 131  * ids which did not previously have a slot.
 132  *
 133  * this code relies on the client spinlock to manage locks, its
 134  * possible we should switch to something else, but I'd rather
 135  * stick with something low-overhead for the common case.
 136  *
 137  */
 138
 139 static struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag)
 140 {
 141         unsigned long flags;
 142         int row, col;
 143         struct p9_req_t *req;
 144
 145         /* This looks up the original request by tag so we know which
 146          * buffer to read the data into */
 147         tag++;
 148
 149         if (tag >= c->max_tag) {
 150                 spin_lock_irqsave(&c->lock, flags);
 151                 /* check again since original check was outside of lock */
 152                 while (tag >= c->max_tag) {
 153                         row = (tag / P9_ROW_MAXTAG);
 154                         c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
 155                                         sizeof(struct p9_req_t), GFP_ATOMIC);
 156
 157                         if (!c->reqs[row]) {
 158                                 printk(KERN_ERR "Couldn't grow tag array\n");
 159                                 spin_unlock_irqrestore(&c->lock, flags);
 160                                 return ERR_PTR(-ENOMEM);
 161                         }
 162                         for (col = 0; col < P9_ROW_MAXTAG; col++) {
 163                                 c->reqs[row][col].status = REQ_STATUS_IDLE;
 164                                 c->reqs[row][col].tc = NULL;
 165                         }
 166                         c->max_tag += P9_ROW_MAXTAG;
 167                 }
 168                 spin_unlock_irqrestore(&c->lock, flags);
 169         }
 170         row = tag / P9_ROW_MAXTAG;
 171         col = tag % P9_ROW_MAXTAG;
 172
 173         req = &c->reqs[row][col];
 174         if (!req->tc) {
 175                 req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_KERNEL);
 176                 if (!req->wq) {
 177                         printk(KERN_ERR "Couldn't grow tag array\n");
 178                         return ERR_PTR(-ENOMEM);
 179                 }
 180                 init_waitqueue_head(req->wq);
 181                 req->tc = kmalloc(sizeof(struct p9_fcall)+c->msize,
 182                                                                 GFP_KERNEL);
 183                 req->rc = kmalloc(sizeof(struct p9_fcall)+c->msize,
 184                                                                 GFP_KERNEL);
 185                 if ((!req->tc) || (!req->rc)) {
 186                         printk(KERN_ERR "Couldn't grow tag array\n");
 187                         kfree(req->tc);
 188                         kfree(req->rc);
 189                         kfree(req->wq);
 190                         req->tc = req->rc = NULL;
 191                         req->wq = NULL;
 192                         return ERR_PTR(-ENOMEM);
 193                 }
 194                 req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
 195                 req->tc->capacity = c->msize;
 196                 req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall);
 197                 req->rc->capacity = c->msize;
 198         }
 199
 200         p9pdu_reset(req->tc);
 201         p9pdu_reset(req->rc);
 202
 203         req->tc->tag = tag-1;
 204         req->status = REQ_STATUS_ALLOC;
 205
 206         return &c->reqs[row][col];
 207 }
 208
 209 /**
 210  * p9_tag_lookup - lookup a request by tag
 211  * @c: client session to lookup tag within
 212  * @tag: numeric id for transaction
 213  *
 214  */
 215
 216 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
 217 {
 218         int row, col;
 219
 220         /* This looks up the original request by tag so we know which
 221          * buffer to read the data into */
 222         tag++;
 223
 224         BUG_ON(tag >= c->max_tag);
 225
 226         row = tag / P9_ROW_MAXTAG;
 227         col = tag % P9_ROW_MAXTAG;
 228
 229         return &c->reqs[row][col];
 230 }
 231 EXPORT_SYMBOL(p9_tag_lookup);
 232
 233 /**
 234  * p9_tag_init - setup tags structure and contents
 235  * @tags: tags structure from the client struct
 236  *
 237  * This initializes the tags structure for each client instance.
 238  *
 239  */
 240
 241 static int p9_tag_init(struct p9_client *c)
 242 {
 243         int err = 0;
 244
 245         c->tagpool = p9_idpool_create();
 246         if (IS_ERR(c->tagpool)) {
 247                 err = PTR_ERR(c->tagpool);
 248                 c->tagpool = NULL;
 249                 goto error;
 250         }
 251
 252         p9_idpool_get(c->tagpool); /* reserve tag 0 */
 253
 254         c->max_tag = 0;
 255 error:
 256         return err;
 257 }
 258
 259 /**
 260  * p9_tag_cleanup - cleans up tags structure and reclaims resources
 261  * @tags: tags structure from the client struct
 262  *
 263  * This frees resources associated with the tags structure
 264  *
 265  */
 266 static void p9_tag_cleanup(struct p9_client *c)
 267 {
 268         int row, col;
 269
 270         /* check to insure all requests are idle */
 271         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 272                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 273                         if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
 274                                 P9_DPRINTK(P9_DEBUG_MUX,
 275                                   "Attempting to cleanup non-free tag %d,%d\n",
 276                                   row, col);
 277                                 /* TODO: delay execution of cleanup */
 278                                 return;
 279                         }
 280                 }
 281         }
 282
 283         if (c->tagpool)
 284                 p9_idpool_destroy(c->tagpool);
 285
 286         /* free requests associated with tags */
 287         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 288                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 289                         kfree(c->reqs[row][col].wq);
 290                         kfree(c->reqs[row][col].tc);
 291                         kfree(c->reqs[row][col].rc);
 292                 }
 293                 kfree(c->reqs[row]);
 294         }
 295         c->max_tag = 0;
 296 }
 297
 298 /**
 299  * p9_free_req - free a request and clean-up as necessary
 300  * c: client state
 301  * r: request to release
 302  *
 303  */
 304
 305 static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
 306 {
 307         int tag = r->tc->tag;
 308         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
 309
 310         r->status = REQ_STATUS_IDLE;
 311         if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
 312                 p9_idpool_put(tag, c->tagpool);
 313 }
 314
 315 /**
 316  * p9_client_cb - call back from transport to client
 317  * c: client state
 318  * req: request received
 319  *
 320  */
 321 void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
 322 {
 323         P9_DPRINTK(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
 324         wake_up(req->wq);
 325         P9_DPRINTK(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
 326 }
 327 EXPORT_SYMBOL(p9_client_cb);
 328
 329 /**
 330  * p9_parse_header - parse header arguments out of a packet
 331  * @pdu: packet to parse
 332  * @size: size of packet
 333  * @type: type of request
 334  * @tag: tag of packet
 335  * @rewind: set if we need to rewind offset afterwards
 336  */
 337
 338 int
 339 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
 340                                                                 int rewind)
 341 {
 342         int8_t r_type;
 343         int16_t r_tag;
 344         int32_t r_size;
 345         int offset = pdu->offset;
 346         int err;
 347
 348         pdu->offset = 0;
 349         if (pdu->size == 0)
 350                 pdu->size = 7;
 351
 352         err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
 353         if (err)
 354                 goto rewind_and_exit;
 355
 356         pdu->size = r_size;
 357         pdu->id = r_type;
 358         pdu->tag = r_tag;
 359
 360         P9_DPRINTK(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n", pdu->size,
 361                                                         pdu->id, pdu->tag);
 362
 363         if (type)
 364                 *type = r_type;
 365         if (tag)
 366                 *tag = r_tag;
 367         if (size)
 368                 *size = r_size;
 369
 370
 371 rewind_and_exit:
 372         if (rewind)
 373                 pdu->offset = offset;
 374         return err;
 375 }
 376 EXPORT_SYMBOL(p9_parse_header);
 377
 378 /**
 379  * p9_check_errors - check 9p packet for error return and process it
 380  * @c: current client instance
 381  * @req: request to parse and check for error conditions
 382  *
 383  * returns error code if one is discovered, otherwise returns 0
 384  *
 385  * this will have to be more complicated if we have multiple
 386  * error packet types
 387  */
 388
 389 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 390 {
 391         int8_t type;
 392         int err;
 393
 394         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 395         if (err) {
 396                 P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 397                 return err;
 398         }
 399
 400         if (type == P9_RERROR) {
 401                 int ecode;
 402                 char *ename;
 403
 404                 err = p9pdu_readf(req->rc, c->dotu, "s?d", &ename, &ecode);
 405                 if (err) {
 406                         P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n",
 407                                                                         err);
 408                         return err;
 409                 }
 410
 411                 if (c->dotu)
 412                         err = -ecode;
 413
 414                 if (!err) {
 415                         err = p9_errstr2errno(ename, strlen(ename));
 416
 417                         /* string match failed */
 418                         if (!err)
 419                                 err = -ESERVERFAULT;
 420                 }
 421
 422                 P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
 423
 424                 kfree(ename);
 425         } else
 426                 err = 0;
 427
 428         return err;
 429 }
 430
 431 /**
 432  * p9_client_flush - flush (cancel) a request
 433  * c: client state
 434  * req: request to cancel
 435  *
 436  * This sents a flush for a particular requests and links
 437  * the flush request to the original request.  The current
 438  * code only supports a single flush request although the protocol
 439  * allows for multiple flush requests to be sent for a single request.
 440  *
 441  */
 442
 443 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 444 {
 445         struct p9_req_t *req;
 446         int16_t oldtag;
 447         int err;
 448
 449         err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
 450         if (err)
 451                 return err;
 452
 453         P9_DPRINTK(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
 454
 455         req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
 456         if (IS_ERR(req))
 457                 return PTR_ERR(req);
 458
 459
 460         /* if we haven't received a response for oldreq,
 461            remove it from the list. */
 462         spin_lock(&c->lock);
 463         if (oldreq->status == REQ_STATUS_FLSH)
 464                 list_del(&oldreq->req_list);
 465         spin_unlock(&c->lock);
 466
 467         p9_free_req(c, req);
 468         return 0;
 469 }
 470
 471 /**
 472  * p9_client_rpc - issue a request and wait for a response
 473  * @c: client session
 474  * @type: type of request
 475  * @fmt: protocol format string (see protocol.c)
 476  *
 477  * Returns request structure (which client must free using p9_free_req)
 478  */
 479
 480 static struct p9_req_t *
 481 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 482 {
 483         va_list ap;
 484         int tag, err;
 485         struct p9_req_t *req;
 486         unsigned long flags;
 487         int sigpending;
 488
 489         P9_DPRINTK(P9_DEBUG_MUX, "client %p op %d\n", c, type);
 490
 491         if (c->status != Connected)
 492                 return ERR_PTR(-EIO);
 493
 494         if (signal_pending(current)) {
 495                 sigpending = 1;
 496                 clear_thread_flag(TIF_SIGPENDING);
 497         } else
 498                 sigpending = 0;
 499
 500         tag = P9_NOTAG;
 501         if (type != P9_TVERSION) {
 502                 tag = p9_idpool_get(c->tagpool);
 503                 if (tag < 0)
 504                         return ERR_PTR(-ENOMEM);
 505         }
 506
 507         req = p9_tag_alloc(c, tag);
 508         if (IS_ERR(req))
 509                 return req;
 510
 511         /* marshall the data */
 512         p9pdu_prepare(req->tc, tag, type);
 513         va_start(ap, fmt);
 514         err = p9pdu_vwritef(req->tc, c->dotu, fmt, ap);
 515         va_end(ap);
 516         p9pdu_finalize(req->tc);
 517
 518         err = c->trans_mod->request(c, req);
 519         if (err < 0) {
 520                 c->status = Disconnected;
 521                 goto reterr;
 522         }
 523
 524         P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d\n", req->wq, tag);
 525         err = wait_event_interruptible(*req->wq,
 526                                                 req->status >= REQ_STATUS_RCVD);
 527         P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d returned %d\n",
 528                                                 req->wq, tag, err);
 529
 530         if (req->status == REQ_STATUS_ERROR) {
 531                 P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 532                 err = req->t_err;
 533         }
 534
 535         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 536                 P9_DPRINTK(P9_DEBUG_MUX, "flushing\n");
 537                 sigpending = 1;
 538                 clear_thread_flag(TIF_SIGPENDING);
 539
 540                 if (c->trans_mod->cancel(c, req))
 541                         p9_client_flush(c, req);
 542
 543                 /* if we received the response anyway, don't signal error */
 544                 if (req->status == REQ_STATUS_RCVD)
 545                         err = 0;
 546         }
 547
 548         if (sigpending) {
 549                 spin_lock_irqsave(&current->sighand->siglock, flags);
 550                 recalc_sigpending();
 551                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 552         }
 553
 554         if (err < 0)
 555                 goto reterr;
 556
 557         err = p9_check_errors(c, req);
 558         if (!err) {
 559                 P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d\n", c, type);
 560                 return req;
 561         }
 562
 563 reterr:
 564         P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d error: %d\n", c, type,
 565                                                                         err);
 566         p9_free_req(c, req);
 567         return ERR_PTR(err);
 568 }
 569
 570 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 571 {
 572         int ret;
 573         struct p9_fid *fid;
 574         unsigned long flags;
 575
 576         P9_DPRINTK(P9_DEBUG_FID, "clnt %p\n", clnt);
 577         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
 578         if (!fid)
 579                 return ERR_PTR(-ENOMEM);
 580
 581         ret = p9_idpool_get(clnt->fidpool);
 582         if (ret < 0) {
 583                 ret = -ENOSPC;
 584                 goto error;
 585         }
 586         fid->fid = ret;
 587
 588         memset(&fid->qid, 0, sizeof(struct p9_qid));
 589         fid->mode = -1;
 590         fid->rdir_fpos = 0;
 591         fid->uid = current_fsuid();
 592         fid->clnt = clnt;
 593         fid->aux = NULL;
 594
 595         spin_lock_irqsave(&clnt->lock, flags);
 596         list_add(&fid->flist, &clnt->fidlist);
 597         spin_unlock_irqrestore(&clnt->lock, flags);
 598
 599         return fid;
 600
 601 error:
 602         kfree(fid);
 603         return ERR_PTR(ret);
 604 }
 605
 606 static void p9_fid_destroy(struct p9_fid *fid)
 607 {
 608         struct p9_client *clnt;
 609         unsigned long flags;
 610
 611         P9_DPRINTK(P9_DEBUG_FID, "fid %d\n", fid->fid);
 612         clnt = fid->clnt;
 613         p9_idpool_put(fid->fid, clnt->fidpool);
 614         spin_lock_irqsave(&clnt->lock, flags);
 615         list_del(&fid->flist);
 616         spin_unlock_irqrestore(&clnt->lock, flags);
 617         kfree(fid);
 618 }
 619
 620 int p9_client_version(struct p9_client *c)
 621 {
 622         int err = 0;
 623         struct p9_req_t *req;
 624         char *version;
 625         int msize;
 626
 627         P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d extended %d\n",
 628                                                         c->msize, c->dotu);
 629         req = p9_client_rpc(c, P9_TVERSION, "ds", c->msize,
 630                                 c->dotu ? "9P2000.u" : "9P2000");
 631         if (IS_ERR(req))
 632                 return PTR_ERR(req);
 633
 634         err = p9pdu_readf(req->rc, c->dotu, "ds", &msize, &version);
 635         if (err) {
 636                 P9_DPRINTK(P9_DEBUG_9P, "version error %d\n", err);
 637                 p9pdu_dump(1, req->rc);
 638                 goto error;
 639         }
 640
 641         P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
 642         if (!memcmp(version, "9P2000.u", 8))
 643                 c->dotu = 1;
 644         else if (!memcmp(version, "9P2000", 6))
 645                 c->dotu = 0;
 646         else {
 647                 err = -EREMOTEIO;
 648                 goto error;
 649         }
 650
 651         if (msize < c->msize)
 652                 c->msize = msize;
 653
 654 error:
 655         kfree(version);
 656         p9_free_req(c, req);
 657
 658         return err;
 659 }
 660 EXPORT_SYMBOL(p9_client_version);
 661
 662 struct p9_client *p9_client_create(const char *dev_name, char *options)
 663 {
 664         int err;
 665         struct p9_client *clnt;
 666
 667         err = 0;
 668         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
 669         if (!clnt)
 670                 return ERR_PTR(-ENOMEM);
 671
 672         clnt->trans_mod = NULL;
 673         clnt->trans = NULL;
 674         spin_lock_init(&clnt->lock);
 675         INIT_LIST_HEAD(&clnt->fidlist);
 676         clnt->fidpool = p9_idpool_create();
 677         if (IS_ERR(clnt->fidpool)) {
 678                 err = PTR_ERR(clnt->fidpool);
 679                 clnt->fidpool = NULL;
 680                 goto error;
 681         }
 682
 683         p9_tag_init(clnt);
 684
 685         err = parse_opts(options, clnt);
 686         if (err < 0)
 687                 goto error;
 688
 689         if (!clnt->trans_mod)
 690                 clnt->trans_mod = v9fs_get_default_trans();
 691
 692         if (clnt->trans_mod == NULL) {
 693                 err = -EPROTONOSUPPORT;
 694                 P9_DPRINTK(P9_DEBUG_ERROR,
 695                                 "No transport defined or default transport\n");
 696                 goto error;
 697         }
 698
 699         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p trans %p msize %d dotu %d\n",
 700                 clnt, clnt->trans_mod, clnt->msize, clnt->dotu);
 701
 702         err = clnt->trans_mod->create(clnt, dev_name, options);
 703         if (err)
 704                 goto error;
 705
 706         if ((clnt->msize+P9_IOHDRSZ) > clnt->trans_mod->maxsize)
 707                 clnt->msize = clnt->trans_mod->maxsize-P9_IOHDRSZ;
 708
 709         err = p9_client_version(clnt);
 710         if (err)
 711                 goto error;
 712
 713         return clnt;
 714
 715 error:
 716         p9_client_destroy(clnt);
 717         return ERR_PTR(err);
 718 }
 719 EXPORT_SYMBOL(p9_client_create);
 720
 721 void p9_client_destroy(struct p9_client *clnt)
 722 {
 723         struct p9_fid *fid, *fidptr;
 724
 725         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p\n", clnt);
 726
 727         if (clnt->trans_mod)
 728                 clnt->trans_mod->close(clnt);
 729
 730         v9fs_put_trans(clnt->trans_mod);
 731
 732         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist)
 733                 p9_fid_destroy(fid);
 734
 735         if (clnt->fidpool)
 736                 p9_idpool_destroy(clnt->fidpool);
 737
 738         p9_tag_cleanup(clnt);
 739
 740         kfree(clnt);
 741 }
 742 EXPORT_SYMBOL(p9_client_destroy);
 743
 744 void p9_client_disconnect(struct p9_client *clnt)
 745 {
 746         P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
 747         clnt->status = Disconnected;
 748 }
 749 EXPORT_SYMBOL(p9_client_disconnect);
 750
 751 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
 752         char *uname, u32 n_uname, char *aname)
 753 {
 754         int err;
 755         struct p9_req_t *req;
 756         struct p9_fid *fid;
 757         struct p9_qid qid;
 758
 759         P9_DPRINTK(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
 760                                         afid ? afid->fid : -1, uname, aname);
 761         err = 0;
 762
 763         fid = p9_fid_create(clnt);
 764         if (IS_ERR(fid)) {
 765                 err = PTR_ERR(fid);
 766                 fid = NULL;
 767                 goto error;
 768         }
 769
 770         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
 771                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
 772         if (IS_ERR(req)) {
 773                 err = PTR_ERR(req);
 774                 goto error;
 775         }
 776
 777         err = p9pdu_readf(req->rc, clnt->dotu, "Q", &qid);
 778         if (err) {
 779                 p9pdu_dump(1, req->rc);
 780                 p9_free_req(clnt, req);
 781                 goto error;
 782         }
 783
 784         P9_DPRINTK(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
 785                                         qid.type,
 786                                         (unsigned long long)qid.path,
 787                                         qid.version);
 788
 789         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
 790
 791         p9_free_req(clnt, req);
 792         return fid;
 793
 794 error:
 795         if (fid)
 796                 p9_fid_destroy(fid);
 797         return ERR_PTR(err);
 798 }
 799 EXPORT_SYMBOL(p9_client_attach);
 800
 801 struct p9_fid *
 802 p9_client_auth(struct p9_client *clnt, char *uname, u32 n_uname, char *aname)
 803 {
 804         int err;
 805         struct p9_req_t *req;
 806         struct p9_qid qid;
 807         struct p9_fid *afid;
 808
 809         P9_DPRINTK(P9_DEBUG_9P, ">>> TAUTH uname %s aname %s\n", uname, aname);
 810         err = 0;
 811
 812         afid = p9_fid_create(clnt);
 813         if (IS_ERR(afid)) {
 814                 err = PTR_ERR(afid);
 815                 afid = NULL;
 816                 goto error;
 817         }
 818
 819         req = p9_client_rpc(clnt, P9_TAUTH, "dss?d",
 820                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
 821         if (IS_ERR(req)) {
 822                 err = PTR_ERR(req);
 823                 goto error;
 824         }
 825
 826         err = p9pdu_readf(req->rc, clnt->dotu, "Q", &qid);
 827         if (err) {
 828                 p9pdu_dump(1, req->rc);
 829                 p9_free_req(clnt, req);
 830                 goto error;
 831         }
 832
 833         P9_DPRINTK(P9_DEBUG_9P, "<<< RAUTH qid %x.%llx.%x\n",
 834                                         qid.type,
 835                                         (unsigned long long)qid.path,
 836                                         qid.version);
 837
 838         memmove(&afid->qid, &qid, sizeof(struct p9_qid));
 839         p9_free_req(clnt, req);
 840         return afid;
 841
 842 error:
 843         if (afid)
 844                 p9_fid_destroy(afid);
 845         return ERR_PTR(err);
 846 }
 847 EXPORT_SYMBOL(p9_client_auth);
 848
 849 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, int nwname, char **wnames,
 850         int clone)
 851 {
 852         int err;
 853         struct p9_client *clnt;
 854         struct p9_fid *fid;
 855         struct p9_qid *wqids;
 856         struct p9_req_t *req;
 857         int16_t nwqids, count;
 858
 859         err = 0;
 860         clnt = oldfid->clnt;
 861         if (clone) {
 862                 fid = p9_fid_create(clnt);
 863                 if (IS_ERR(fid)) {
 864                         err = PTR_ERR(fid);
 865                         fid = NULL;
 866                         goto error;
 867                 }
 868
 869                 fid->uid = oldfid->uid;
 870         } else
 871                 fid = oldfid;
 872
 873
 874         P9_DPRINTK(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %d wname[0] %s\n",
 875                 oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
 876
 877         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
 878                                                                 nwname, wnames);
 879         if (IS_ERR(req)) {
 880                 err = PTR_ERR(req);
 881                 goto error;
 882         }
 883
 884         err = p9pdu_readf(req->rc, clnt->dotu, "R", &nwqids, &wqids);
 885         if (err) {
 886                 p9pdu_dump(1, req->rc);
 887                 p9_free_req(clnt, req);
 888                 goto clunk_fid;
 889         }
 890         p9_free_req(clnt, req);
 891
 892         P9_DPRINTK(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
 893
 894         if (nwqids != nwname) {
 895                 err = -ENOENT;
 896                 goto clunk_fid;
 897         }
 898
 899         for (count = 0; count < nwqids; count++)
 900                 P9_DPRINTK(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
 901                         count, wqids[count].type,
 902                         (unsigned long long)wqids[count].path,
 903                         wqids[count].version);
 904
 905         if (nwname)
 906                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
 907         else
 908                 fid->qid = oldfid->qid;
 909
 910         return fid;
 911
 912 clunk_fid:
 913         p9_client_clunk(fid);
 914         fid = NULL;
 915
 916 error:
 917         if (fid && (fid != oldfid))
 918                 p9_fid_destroy(fid);
 919
 920         return ERR_PTR(err);
 921 }
 922 EXPORT_SYMBOL(p9_client_walk);
 923
 924 int p9_client_open(struct p9_fid *fid, int mode)
 925 {
 926         int err;
 927         struct p9_client *clnt;
 928         struct p9_req_t *req;
 929         struct p9_qid qid;
 930         int iounit;
 931
 932         P9_DPRINTK(P9_DEBUG_9P, ">>> TOPEN fid %d mode %d\n", fid->fid, mode);
 933         err = 0;
 934         clnt = fid->clnt;
 935
 936         if (fid->mode != -1)
 937                 return -EINVAL;
 938
 939         req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
 940         if (IS_ERR(req)) {
 941                 err = PTR_ERR(req);
 942                 goto error;
 943         }
 944
 945         err = p9pdu_readf(req->rc, clnt->dotu, "Qd", &qid, &iounit);
 946         if (err) {
 947                 p9pdu_dump(1, req->rc);
 948                 goto free_and_error;
 949         }
 950
 951         P9_DPRINTK(P9_DEBUG_9P, "<<< ROPEN qid %x.%llx.%x iounit %x\n",
 952                                 qid.type,
 953                                 (unsigned long long)qid.path,
 954                                 qid.version, iounit);
 955
 956         fid->mode = mode;
 957         fid->iounit = iounit;
 958
 959 free_and_error:
 960         p9_free_req(clnt, req);
 961 error:
 962         return err;
 963 }
 964 EXPORT_SYMBOL(p9_client_open);
 965
 966 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
 967                      char *extension)
 968 {
 969         int err;
 970         struct p9_client *clnt;
 971         struct p9_req_t *req;
 972         struct p9_qid qid;
 973         int iounit;
 974
 975         P9_DPRINTK(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
 976                                                 fid->fid, name, perm, mode);
 977         err = 0;
 978         clnt = fid->clnt;
 979
 980         if (fid->mode != -1)
 981                 return -EINVAL;
 982
 983         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
 984                                 mode, extension);
 985         if (IS_ERR(req)) {
 986                 err = PTR_ERR(req);
 987                 goto error;
 988         }
 989
 990         err = p9pdu_readf(req->rc, clnt->dotu, "Qd", &qid, &iounit);
 991         if (err) {
 992                 p9pdu_dump(1, req->rc);
 993                 goto free_and_error;
 994         }
 995
 996         P9_DPRINTK(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
 997                                 qid.type,
 998                                 (unsigned long long)qid.path,
 999                                 qid.version, iounit);
1000
1001         fid->mode = mode;
1002         fid->iounit = iounit;
1003
1004 free_and_error:
1005         p9_free_req(clnt, req);
1006 error:
1007         return err;
1008 }
1009 EXPORT_SYMBOL(p9_client_fcreate);
1010
1011 int p9_client_clunk(struct p9_fid *fid)
1012 {
1013         int err;
1014         struct p9_client *clnt;
1015         struct p9_req_t *req;
1016
1017         P9_DPRINTK(P9_DEBUG_9P, ">>> TCLUNK fid %d\n", fid->fid);
1018         err = 0;
1019         clnt = fid->clnt;
1020
1021         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1022         if (IS_ERR(req)) {
1023                 err = PTR_ERR(req);
1024                 goto error;
1025         }
1026
1027         P9_DPRINTK(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1028
1029         p9_free_req(clnt, req);
1030         p9_fid_destroy(fid);
1031
1032 error:
1033         return err;
1034 }
1035 EXPORT_SYMBOL(p9_client_clunk);
1036
1037 int p9_client_remove(struct p9_fid *fid)
1038 {
1039         int err;
1040         struct p9_client *clnt;
1041         struct p9_req_t *req;
1042
1043         P9_DPRINTK(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1044         err = 0;
1045         clnt = fid->clnt;
1046
1047         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1048         if (IS_ERR(req)) {
1049                 err = PTR_ERR(req);
1050                 goto error;
1051         }
1052
1053         P9_DPRINTK(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1054
1055         p9_free_req(clnt, req);
1056         p9_fid_destroy(fid);
1057
1058 error:
1059         return err;
1060 }
1061 EXPORT_SYMBOL(p9_client_remove);
1062
1063 int
1064 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1065                                                                 u32 count)
1066 {
1067         int err, rsize, total;
1068         struct p9_client *clnt;
1069         struct p9_req_t *req;
1070         char *dataptr;
1071
1072         P9_DPRINTK(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n", fid->fid,
1073                                         (long long unsigned) offset, count);
1074         err = 0;
1075         clnt = fid->clnt;
1076         total = 0;
1077
1078         rsize = fid->iounit;
1079         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1080                 rsize = clnt->msize - P9_IOHDRSZ;
1081
1082         if (count < rsize)
1083                 rsize = count;
1084
1085         req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset, rsize);
1086         if (IS_ERR(req)) {
1087                 err = PTR_ERR(req);
1088                 goto error;
1089         }
1090
1091         err = p9pdu_readf(req->rc, clnt->dotu, "D", &count, &dataptr);
1092         if (err) {
1093                 p9pdu_dump(1, req->rc);
1094                 goto free_and_error;
1095         }
1096
1097         P9_DPRINTK(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1098
1099         if (data) {
1100                 memmove(data, dataptr, count);
1101         }
1102
1103         if (udata) {
1104                 err = copy_to_user(udata, dataptr, count);
1105                 if (err) {
1106                         err = -EFAULT;
1107                         goto free_and_error;
1108                 }
1109         }
1110
1111         p9_free_req(clnt, req);
1112         return count;
1113
1114 free_and_error:
1115         p9_free_req(clnt, req);
1116 error:
1117         return err;
1118 }
1119 EXPORT_SYMBOL(p9_client_read);
1120
1121 int
1122 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1123                                                         u64 offset, u32 count)
1124 {
1125         int err, rsize, total;
1126         struct p9_client *clnt;
1127         struct p9_req_t *req;
1128
1129         P9_DPRINTK(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1130                                 fid->fid, (long long unsigned) offset, count);
1131         err = 0;
1132         clnt = fid->clnt;
1133         total = 0;
1134
1135         rsize = fid->iounit;
1136         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1137                 rsize = clnt->msize - P9_IOHDRSZ;
1138
1139         if (count < rsize)
1140                 rsize = count;
1141         if (data)
1142                 req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid, offset,
1143                                                                 rsize, data);
1144         else
1145                 req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid, offset,
1146                                                                 rsize, udata);
1147         if (IS_ERR(req)) {
1148                 err = PTR_ERR(req);
1149                 goto error;
1150         }
1151
1152         err = p9pdu_readf(req->rc, clnt->dotu, "d", &count);
1153         if (err) {
1154                 p9pdu_dump(1, req->rc);
1155                 goto free_and_error;
1156         }
1157
1158         P9_DPRINTK(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1159
1160         p9_free_req(clnt, req);
1161         return count;
1162
1163 free_and_error:
1164         p9_free_req(clnt, req);
1165 error:
1166         return err;
1167 }
1168 EXPORT_SYMBOL(p9_client_write);
1169
1170 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1171 {
1172         int err;
1173         struct p9_client *clnt;
1174         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1175         struct p9_req_t *req;
1176         u16 ignored;
1177
1178         P9_DPRINTK(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1179
1180         if (!ret)
1181                 return ERR_PTR(-ENOMEM);
1182
1183         err = 0;
1184         clnt = fid->clnt;
1185
1186         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1187         if (IS_ERR(req)) {
1188                 err = PTR_ERR(req);
1189                 goto error;
1190         }
1191
1192         err = p9pdu_readf(req->rc, clnt->dotu, "wS", &ignored, ret);
1193         if (err) {
1194                 p9pdu_dump(1, req->rc);
1195                 p9_free_req(clnt, req);
1196                 goto error;
1197         }
1198
1199         P9_DPRINTK(P9_DEBUG_9P,
1200                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1201                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1202                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1203                 "<<<    uid=%d gid=%d n_muid=%d\n",
1204                 ret->size, ret->type, ret->dev, ret->qid.type,
1205                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1206                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1207                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1208                 ret->n_uid, ret->n_gid, ret->n_muid);
1209
1210         p9_free_req(clnt, req);
1211         return ret;
1212
1213 error:
1214         kfree(ret);
1215         return ERR_PTR(err);
1216 }
1217 EXPORT_SYMBOL(p9_client_stat);
1218
1219 static int p9_client_statsize(struct p9_wstat *wst, int optional)
1220 {
1221         int ret;
1222
1223         /* size[2] type[2] dev[4] qid[13] */
1224         /* mode[4] atime[4] mtime[4] length[8]*/
1225         /* name[s] uid[s] gid[s] muid[s] */
1226         ret = 2+2+4+13+4+4+4+8+2+2+2+2;
1227
1228         if (wst->name)
1229                 ret += strlen(wst->name);
1230         if (wst->uid)
1231                 ret += strlen(wst->uid);
1232         if (wst->gid)
1233                 ret += strlen(wst->gid);
1234         if (wst->muid)
1235                 ret += strlen(wst->muid);
1236
1237         if (optional) {
1238                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1239                 if (wst->extension)
1240                         ret += strlen(wst->extension);
1241         }
1242
1243         return ret;
1244 }
1245
1246 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1247 {
1248         int err;
1249         struct p9_req_t *req;
1250         struct p9_client *clnt;
1251
1252         err = 0;
1253         clnt = fid->clnt;
1254         wst->size = p9_client_statsize(wst, clnt->dotu);
1255         P9_DPRINTK(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1256         P9_DPRINTK(P9_DEBUG_9P,
1257                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1258                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1259                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1260                 "     uid=%d gid=%d n_muid=%d\n",
1261                 wst->size, wst->type, wst->dev, wst->qid.type,
1262                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1263                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1264                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1265                 wst->n_uid, wst->n_gid, wst->n_muid);
1266
1267         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size, wst);
1268         if (IS_ERR(req)) {
1269                 err = PTR_ERR(req);
1270                 goto error;
1271         }
1272
1273         P9_DPRINTK(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1274
1275         p9_free_req(clnt, req);
1276 error:
1277         return err;
1278 }
1279 EXPORT_SYMBOL(p9_client_wstat);