net/9p/client.c

   1 /*
   2  * net/9p/clnt.c
   3  *
   4  * 9P Client
   5  *
   6  *  Copyright (C) 2008 by Eric Van Hensbergen <[email protected]>
   7  *  Copyright (C) 2007 by Latchesar Ionkov <[email protected]>
   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         if (!clnt->trans_mod)
 121                 clnt->trans_mod = v9fs_get_default_trans();
 122
 123         kfree(options);
 124         return ret;
 125 }
 126
 127 /**
 128  * p9_tag_alloc - lookup/allocate a request by tag
 129  * @c: client session to lookup tag within
 130  * @tag: numeric id for transaction
 131  *
 132  * this is a simple array lookup, but will grow the
 133  * request_slots as necessary to accomodate transaction
 134  * ids which did not previously have a slot.
 135  *
 136  * this code relies on the client spinlock to manage locks, its
 137  * possible we should switch to something else, but I'd rather
 138  * stick with something low-overhead for the common case.
 139  *
 140  */
 141
 142 static struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag)
 143 {
 144         unsigned long flags;
 145         int row, col;
 146         struct p9_req_t *req;
 147
 148         /* This looks up the original request by tag so we know which
 149          * buffer to read the data into */
 150         tag++;
 151
 152         if (tag >= c->max_tag) {
 153                 spin_lock_irqsave(&c->lock, flags);
 154                 /* check again since original check was outside of lock */
 155                 while (tag >= c->max_tag) {
 156                         row = (tag / P9_ROW_MAXTAG);
 157                         c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
 158                                         sizeof(struct p9_req_t), GFP_ATOMIC);
 159
 160                         if (!c->reqs[row]) {
 161                                 printk(KERN_ERR "Couldn't grow tag array\n");
 162                                 return ERR_PTR(-ENOMEM);
 163                         }
 164                         for (col = 0; col < P9_ROW_MAXTAG; col++) {
 165                                 c->reqs[row][col].status = REQ_STATUS_IDLE;
 166                                 c->reqs[row][col].tc = NULL;
 167                         }
 168                         c->max_tag += P9_ROW_MAXTAG;
 169                 }
 170                 spin_unlock_irqrestore(&c->lock, flags);
 171         }
 172         row = tag / P9_ROW_MAXTAG;
 173         col = tag % P9_ROW_MAXTAG;
 174
 175         req = &c->reqs[row][col];
 176         if (!req->tc) {
 177                 req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_KERNEL);
 178                 if (!req->wq) {
 179                         printk(KERN_ERR "Couldn't grow tag array\n");
 180                         return ERR_PTR(-ENOMEM);
 181                 }
 182                 init_waitqueue_head(req->wq);
 183                 req->tc = kmalloc(sizeof(struct p9_fcall)+c->msize,
 184                                                                 GFP_KERNEL);
 185                 req->rc = kmalloc(sizeof(struct p9_fcall)+c->msize,
 186                                                                 GFP_KERNEL);
 187                 if ((!req->tc) || (!req->rc)) {
 188                         printk(KERN_ERR "Couldn't grow tag array\n");
 189                         kfree(req->tc);
 190                         kfree(req->rc);
 191                         return ERR_PTR(-ENOMEM);
 192                 }
 193                 req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
 194                 req->tc->capacity = c->msize;
 195                 req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall);
 196                 req->rc->capacity = c->msize;
 197         }
 198
 199         p9pdu_reset(req->tc);
 200         p9pdu_reset(req->rc);
 201
 202         req->flush_tag = 0;
 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         /* if this was a flush request we have to free response fcall */
 315         if (r->rc->id == P9_RFLUSH) {
 316                 kfree(r->tc);
 317                 kfree(r->rc);
 318         }
 319 }
 320
 321 /**
 322  * p9_client_cb - call back from transport to client
 323  * c: client state
 324  * req: request received
 325  *
 326  */
 327 void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
 328 {
 329         struct p9_req_t *other_req;
 330         unsigned long flags;
 331
 332         P9_DPRINTK(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
 333
 334         if (req->status == REQ_STATUS_ERROR)
 335                 wake_up(req->wq);
 336
 337         if (req->flush_tag) {                   /* flush receive path */
 338                 P9_DPRINTK(P9_DEBUG_9P, "<<< RFLUSH %d\n", req->tc->tag);
 339                 spin_lock_irqsave(&c->lock, flags);
 340                 other_req = p9_tag_lookup(c, req->flush_tag);
 341                 if (other_req->status != REQ_STATUS_FLSH) /* stale flush */
 342                         spin_unlock_irqrestore(&c->lock, flags);
 343                 else {
 344                         other_req->status = REQ_STATUS_FLSHD;
 345                         spin_unlock_irqrestore(&c->lock, flags);
 346                         wake_up(other_req->wq);
 347                 }
 348                 p9_free_req(c, req);
 349         } else {                                /* normal receive path */
 350                 P9_DPRINTK(P9_DEBUG_MUX, "normal: tag %d\n", req->tc->tag);
 351                 spin_lock_irqsave(&c->lock, flags);
 352                 if (req->status != REQ_STATUS_FLSHD)
 353                         req->status = REQ_STATUS_RCVD;
 354                 spin_unlock_irqrestore(&c->lock, flags);
 355                 wake_up(req->wq);
 356                 P9_DPRINTK(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
 357         }
 358 }
 359 EXPORT_SYMBOL(p9_client_cb);
 360
 361 /**
 362  * p9_parse_header - parse header arguments out of a packet
 363  * @pdu: packet to parse
 364  * @size: size of packet
 365  * @type: type of request
 366  * @tag: tag of packet
 367  * @rewind: set if we need to rewind offset afterwards
 368  */
 369
 370 int
 371 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
 372                                                                 int rewind)
 373 {
 374         int8_t r_type;
 375         int16_t r_tag;
 376         int32_t r_size;
 377         int offset = pdu->offset;
 378         int err;
 379
 380         pdu->offset = 0;
 381         if (pdu->size == 0)
 382                 pdu->size = 7;
 383
 384         err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
 385         if (err)
 386                 goto rewind_and_exit;
 387
 388         pdu->size = r_size;
 389         pdu->id = r_type;
 390         pdu->tag = r_tag;
 391
 392         P9_DPRINTK(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n", pdu->size,
 393                                                         pdu->id, pdu->tag);
 394
 395         if (type)
 396                 *type = r_type;
 397         if (tag)
 398                 *tag = r_tag;
 399         if (size)
 400                 *size = r_size;
 401
 402
 403 rewind_and_exit:
 404         if (rewind)
 405                 pdu->offset = offset;
 406         return err;
 407 }
 408 EXPORT_SYMBOL(p9_parse_header);
 409
 410 /**
 411  * p9_check_errors - check 9p packet for error return and process it
 412  * @c: current client instance
 413  * @req: request to parse and check for error conditions
 414  *
 415  * returns error code if one is discovered, otherwise returns 0
 416  *
 417  * this will have to be more complicated if we have multiple
 418  * error packet types
 419  */
 420
 421 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 422 {
 423         int8_t type;
 424         int err;
 425
 426         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 427         if (err) {
 428                 P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 429                 return err;
 430         }
 431
 432         if (type == P9_RERROR) {
 433                 int ecode;
 434                 char *ename;
 435
 436                 err = p9pdu_readf(req->rc, c->dotu, "s?d", &ename, &ecode);
 437                 if (err) {
 438                         P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n",
 439                                                                         err);
 440                         return err;
 441                 }
 442
 443                 if (c->dotu)
 444                         err = -ecode;
 445
 446                 if (!err) {
 447                         err = p9_errstr2errno(ename, strlen(ename));
 448
 449                         /* string match failed */
 450                         if (!err)
 451                                 err = -ESERVERFAULT;
 452                 }
 453
 454                 P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
 455
 456                 kfree(ename);
 457         } else
 458                 err = 0;
 459
 460         return err;
 461 }
 462
 463 /**
 464  * p9_client_flush - flush (cancel) a request
 465  * c: client state
 466  * req: request to cancel
 467  *
 468  * This sents a flush for a particular requests and links
 469  * the flush request to the original request.  The current
 470  * code only supports a single flush request although the protocol
 471  * allows for multiple flush requests to be sent for a single request.
 472  *
 473  */
 474
 475 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 476 {
 477         struct p9_req_t *req;
 478         int16_t oldtag;
 479         int err;
 480
 481         err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
 482         if (err)
 483                 return err;
 484
 485         P9_DPRINTK(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
 486
 487         req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
 488         if (IS_ERR(req))
 489                 return PTR_ERR(req);
 490
 491         req->flush_tag = oldtag;
 492
 493         /* we don't free anything here because RPC isn't complete */
 494         return 0;
 495 }
 496
 497 /**
 498  * p9_client_rpc - issue a request and wait for a response
 499  * @c: client session
 500  * @type: type of request
 501  * @fmt: protocol format string (see protocol.c)
 502  *
 503  * Returns request structure (which client must free using p9_free_req)
 504  */
 505
 506 static struct p9_req_t *
 507 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 508 {
 509         va_list ap;
 510         int tag, err;
 511         struct p9_req_t *req;
 512         unsigned long flags;
 513         int sigpending;
 514         int flushed = 0;
 515
 516         P9_DPRINTK(P9_DEBUG_MUX, "client %p op %d\n", c, type);
 517
 518         if (c->status != Connected)
 519                 return ERR_PTR(-EIO);
 520
 521         if (signal_pending(current)) {
 522                 sigpending = 1;
 523                 clear_thread_flag(TIF_SIGPENDING);
 524         } else
 525                 sigpending = 0;
 526
 527         tag = P9_NOTAG;
 528         if (type != P9_TVERSION) {
 529                 tag = p9_idpool_get(c->tagpool);
 530                 if (tag < 0)
 531                         return ERR_PTR(-ENOMEM);
 532         }
 533
 534         req = p9_tag_alloc(c, tag);
 535         if (IS_ERR(req))
 536                 return req;
 537
 538         /* marshall the data */
 539         p9pdu_prepare(req->tc, tag, type);
 540         va_start(ap, fmt);
 541         err = p9pdu_vwritef(req->tc, c->dotu, fmt, ap);
 542         va_end(ap);
 543         p9pdu_finalize(req->tc);
 544
 545         err = c->trans_mod->request(c, req);
 546         if (err < 0) {
 547                 c->status = Disconnected;
 548                 goto reterr;
 549         }
 550
 551         /* if it was a flush we just transmitted, return our tag */
 552         if (type == P9_TFLUSH)
 553                 return req;
 554 again:
 555         P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d\n", req->wq, tag);
 556         err = wait_event_interruptible(*req->wq,
 557                                                 req->status >= REQ_STATUS_RCVD);
 558         P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d returned %d (flushed=%d)\n",
 559                                                 req->wq, tag, err, flushed);
 560
 561         if (req->status == REQ_STATUS_ERROR) {
 562                 P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 563                 err = req->t_err;
 564         } else if (err == -ERESTARTSYS && flushed) {
 565                 P9_DPRINTK(P9_DEBUG_MUX, "flushed - going again\n");
 566                 goto again;
 567         } else if (req->status == REQ_STATUS_FLSHD) {
 568                 P9_DPRINTK(P9_DEBUG_MUX, "flushed - erestartsys\n");
 569                 err = -ERESTARTSYS;
 570         }
 571
 572         if ((err == -ERESTARTSYS) && (c->status == Connected) && (!flushed)) {
 573                 P9_DPRINTK(P9_DEBUG_MUX, "flushing\n");
 574                 spin_lock_irqsave(&c->lock, flags);
 575                 if (req->status == REQ_STATUS_SENT)
 576                         req->status = REQ_STATUS_FLSH;
 577                 spin_unlock_irqrestore(&c->lock, flags);
 578                 sigpending = 1;
 579                 flushed = 1;
 580                 clear_thread_flag(TIF_SIGPENDING);
 581
 582                 if (c->trans_mod->cancel(c, req)) {
 583                         err = p9_client_flush(c, req);
 584                         if (err == 0)
 585                                 goto again;
 586                 }
 587         }
 588
 589         if (sigpending) {
 590                 spin_lock_irqsave(&current->sighand->siglock, flags);
 591                 recalc_sigpending();
 592                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 593         }
 594
 595         if (err < 0)
 596                 goto reterr;
 597
 598         err = p9_check_errors(c, req);
 599         if (!err) {
 600                 P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d\n", c, type);
 601                 return req;
 602         }
 603
 604 reterr:
 605         P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d error: %d\n", c, type,
 606                                                                         err);
 607         p9_free_req(c, req);
 608         return ERR_PTR(err);
 609 }
 610
 611 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 612 {
 613         int err;
 614         struct p9_fid *fid;
 615
 616         P9_DPRINTK(P9_DEBUG_FID, "clnt %p\n", clnt);
 617         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
 618         if (!fid)
 619                 return ERR_PTR(-ENOMEM);
 620
 621         fid->fid = p9_idpool_get(clnt->fidpool);
 622         if (fid->fid < 0) {
 623                 err = -ENOSPC;
 624                 goto error;
 625         }
 626
 627         memset(&fid->qid, 0, sizeof(struct p9_qid));
 628         fid->mode = -1;
 629         fid->rdir_fpos = 0;
 630         fid->uid = current->fsuid;
 631         fid->clnt = clnt;
 632         fid->aux = NULL;
 633
 634         spin_lock(&clnt->lock);
 635         list_add(&fid->flist, &clnt->fidlist);
 636         spin_unlock(&clnt->lock);
 637
 638         return fid;
 639
 640 error:
 641         kfree(fid);
 642         return ERR_PTR(err);
 643 }
 644
 645 static void p9_fid_destroy(struct p9_fid *fid)
 646 {
 647         struct p9_client *clnt;
 648
 649         P9_DPRINTK(P9_DEBUG_FID, "fid %d\n", fid->fid);
 650         clnt = fid->clnt;
 651         p9_idpool_put(fid->fid, clnt->fidpool);
 652         spin_lock(&clnt->lock);
 653         list_del(&fid->flist);
 654         spin_unlock(&clnt->lock);
 655         kfree(fid);
 656 }
 657
 658 int p9_client_version(struct p9_client *c)
 659 {
 660         int err = 0;
 661         struct p9_req_t *req;
 662         char *version;
 663         int msize;
 664
 665         P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d extended %d\n",
 666                                                         c->msize, c->dotu);
 667         req = p9_client_rpc(c, P9_TVERSION, "ds", c->msize,
 668                                 c->dotu ? "9P2000.u" : "9P2000");
 669         if (IS_ERR(req))
 670                 return PTR_ERR(req);
 671
 672         err = p9pdu_readf(req->rc, c->dotu, "ds", &msize, &version);
 673         if (err) {
 674                 P9_DPRINTK(P9_DEBUG_9P, "version error %d\n", err);
 675                 p9pdu_dump(1, req->rc);
 676                 goto error;
 677         }
 678
 679         P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
 680         if (!memcmp(version, "9P2000.u", 8))
 681                 c->dotu = 1;
 682         else if (!memcmp(version, "9P2000", 6))
 683                 c->dotu = 0;
 684         else {
 685                 err = -EREMOTEIO;
 686                 goto error;
 687         }
 688
 689         if (msize < c->msize)
 690                 c->msize = msize;
 691
 692 error:
 693         kfree(version);
 694         p9_free_req(c, req);
 695
 696         return err;
 697 }
 698 EXPORT_SYMBOL(p9_client_version);
 699
 700 struct p9_client *p9_client_create(const char *dev_name, char *options)
 701 {
 702         int err;
 703         struct p9_client *clnt;
 704
 705         err = 0;
 706         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
 707         if (!clnt)
 708                 return ERR_PTR(-ENOMEM);
 709
 710         clnt->trans_mod = NULL;
 711         clnt->trans = NULL;
 712         spin_lock_init(&clnt->lock);
 713         INIT_LIST_HEAD(&clnt->fidlist);
 714         clnt->fidpool = p9_idpool_create();
 715         if (IS_ERR(clnt->fidpool)) {
 716                 err = PTR_ERR(clnt->fidpool);
 717                 clnt->fidpool = NULL;
 718                 goto error;
 719         }
 720
 721         p9_tag_init(clnt);
 722
 723         err = parse_opts(options, clnt);
 724         if (err < 0)
 725                 goto error;
 726
 727         if (clnt->trans_mod == NULL) {
 728                 err = -EPROTONOSUPPORT;
 729                 P9_DPRINTK(P9_DEBUG_ERROR,
 730                                 "No transport defined or default transport\n");
 731                 goto error;
 732         }
 733
 734         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p trans %p msize %d dotu %d\n",
 735                 clnt, clnt->trans_mod, clnt->msize, clnt->dotu);
 736
 737         err = clnt->trans_mod->create(clnt, dev_name, options);
 738         if (err)
 739                 goto error;
 740
 741         if ((clnt->msize+P9_IOHDRSZ) > clnt->trans_mod->maxsize)
 742                 clnt->msize = clnt->trans_mod->maxsize-P9_IOHDRSZ;
 743
 744         err = p9_client_version(clnt);
 745         if (err)
 746                 goto error;
 747
 748         return clnt;
 749
 750 error:
 751         p9_client_destroy(clnt);
 752         return ERR_PTR(err);
 753 }
 754 EXPORT_SYMBOL(p9_client_create);
 755
 756 void p9_client_destroy(struct p9_client *clnt)
 757 {
 758         struct p9_fid *fid, *fidptr;
 759
 760         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p\n", clnt);
 761
 762         if (clnt->trans_mod)
 763                 clnt->trans_mod->close(clnt);
 764
 765         v9fs_put_trans(clnt->trans_mod);
 766
 767         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist)
 768                 p9_fid_destroy(fid);
 769
 770         if (clnt->fidpool)
 771                 p9_idpool_destroy(clnt->fidpool);
 772
 773         p9_tag_cleanup(clnt);
 774
 775         kfree(clnt);
 776 }
 777 EXPORT_SYMBOL(p9_client_destroy);
 778
 779 void p9_client_disconnect(struct p9_client *clnt)
 780 {
 781         P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
 782         clnt->status = Disconnected;
 783 }
 784 EXPORT_SYMBOL(p9_client_disconnect);
 785
 786 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
 787         char *uname, u32 n_uname, char *aname)
 788 {
 789         int err;
 790         struct p9_req_t *req;
 791         struct p9_fid *fid;
 792         struct p9_qid qid;
 793
 794         P9_DPRINTK(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
 795                                         afid ? afid->fid : -1, uname, aname);
 796         err = 0;
 797
 798         fid = p9_fid_create(clnt);
 799         if (IS_ERR(fid)) {
 800                 err = PTR_ERR(fid);
 801                 fid = NULL;
 802                 goto error;
 803         }
 804
 805         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
 806                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
 807         if (IS_ERR(req)) {
 808                 err = PTR_ERR(req);
 809                 goto error;
 810         }
 811
 812         err = p9pdu_readf(req->rc, clnt->dotu, "Q", &qid);
 813         if (err) {
 814                 p9pdu_dump(1, req->rc);
 815                 p9_free_req(clnt, req);
 816                 goto error;
 817         }
 818
 819         P9_DPRINTK(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
 820                                         qid.type, qid.path, qid.version);
 821
 822         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
 823
 824         p9_free_req(clnt, req);
 825         return fid;
 826
 827 error:
 828         if (fid)
 829                 p9_fid_destroy(fid);
 830         return ERR_PTR(err);
 831 }
 832 EXPORT_SYMBOL(p9_client_attach);
 833
 834 struct p9_fid *
 835 p9_client_auth(struct p9_client *clnt, char *uname, u32 n_uname, char *aname)
 836 {
 837         int err;
 838         struct p9_req_t *req;
 839         struct p9_qid qid;
 840         struct p9_fid *afid;
 841
 842         P9_DPRINTK(P9_DEBUG_9P, ">>> TAUTH uname %s aname %s\n", uname, aname);
 843         err = 0;
 844
 845         afid = p9_fid_create(clnt);
 846         if (IS_ERR(afid)) {
 847                 err = PTR_ERR(afid);
 848                 afid = NULL;
 849                 goto error;
 850         }
 851
 852         req = p9_client_rpc(clnt, P9_TAUTH, "dss?d",
 853                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
 854         if (IS_ERR(req)) {
 855                 err = PTR_ERR(req);
 856                 goto error;
 857         }
 858
 859         err = p9pdu_readf(req->rc, clnt->dotu, "Q", &qid);
 860         if (err) {
 861                 p9pdu_dump(1, req->rc);
 862                 p9_free_req(clnt, req);
 863                 goto error;
 864         }
 865
 866         P9_DPRINTK(P9_DEBUG_9P, "<<< RAUTH qid %x.%llx.%x\n",
 867                                         qid.type, qid.path, qid.version);
 868
 869         memmove(&afid->qid, &qid, sizeof(struct p9_qid));
 870         p9_free_req(clnt, req);
 871         return afid;
 872
 873 error:
 874         if (afid)
 875                 p9_fid_destroy(afid);
 876         return ERR_PTR(err);
 877 }
 878 EXPORT_SYMBOL(p9_client_auth);
 879
 880 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, int nwname, char **wnames,
 881         int clone)
 882 {
 883         int err;
 884         struct p9_client *clnt;
 885         struct p9_fid *fid;
 886         struct p9_qid *wqids;
 887         struct p9_req_t *req;
 888         int16_t nwqids, count;
 889
 890         err = 0;
 891         clnt = oldfid->clnt;
 892         if (clone) {
 893                 fid = p9_fid_create(clnt);
 894                 if (IS_ERR(fid)) {
 895                         err = PTR_ERR(fid);
 896                         fid = NULL;
 897                         goto error;
 898                 }
 899
 900                 fid->uid = oldfid->uid;
 901         } else
 902                 fid = oldfid;
 903
 904
 905         P9_DPRINTK(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %d wname[0] %s\n",
 906                 oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
 907
 908         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
 909                                                                 nwname, wnames);
 910         if (IS_ERR(req)) {
 911                 err = PTR_ERR(req);
 912                 goto error;
 913         }
 914
 915         err = p9pdu_readf(req->rc, clnt->dotu, "R", &nwqids, &wqids);
 916         if (err) {
 917                 p9pdu_dump(1, req->rc);
 918                 p9_free_req(clnt, req);
 919                 goto clunk_fid;
 920         }
 921         p9_free_req(clnt, req);
 922
 923         P9_DPRINTK(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
 924
 925         if (nwqids != nwname) {
 926                 err = -ENOENT;
 927                 goto clunk_fid;
 928         }
 929
 930         for (count = 0; count < nwqids; count++)
 931                 P9_DPRINTK(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
 932                         count, wqids[count].type, wqids[count].path,
 933                         wqids[count].version);
 934
 935         if (nwname)
 936                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
 937         else
 938                 fid->qid = oldfid->qid;
 939
 940         return fid;
 941
 942 clunk_fid:
 943         p9_client_clunk(fid);
 944         fid = NULL;
 945
 946 error:
 947         if (fid && (fid != oldfid))
 948                 p9_fid_destroy(fid);
 949
 950         return ERR_PTR(err);
 951 }
 952 EXPORT_SYMBOL(p9_client_walk);
 953
 954 int p9_client_open(struct p9_fid *fid, int mode)
 955 {
 956         int err;
 957         struct p9_client *clnt;
 958         struct p9_req_t *req;
 959         struct p9_qid qid;
 960         int iounit;
 961
 962         P9_DPRINTK(P9_DEBUG_9P, ">>> TOPEN fid %d mode %d\n", fid->fid, mode);
 963         err = 0;
 964         clnt = fid->clnt;
 965
 966         if (fid->mode != -1)
 967                 return -EINVAL;
 968
 969         req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
 970         if (IS_ERR(req)) {
 971                 err = PTR_ERR(req);
 972                 goto error;
 973         }
 974
 975         err = p9pdu_readf(req->rc, clnt->dotu, "Qd", &qid, &iounit);
 976         if (err) {
 977                 p9pdu_dump(1, req->rc);
 978                 goto free_and_error;
 979         }
 980
 981         P9_DPRINTK(P9_DEBUG_9P, "<<< ROPEN qid %x.%llx.%x iounit %x\n",
 982                                 qid.type, qid.path, qid.version, iounit);
 983
 984         fid->mode = mode;
 985         fid->iounit = iounit;
 986
 987 free_and_error:
 988         p9_free_req(clnt, req);
 989 error:
 990         return err;
 991 }
 992 EXPORT_SYMBOL(p9_client_open);
 993
 994 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
 995                      char *extension)
 996 {
 997         int err;
 998         struct p9_client *clnt;
 999         struct p9_req_t *req;
1000         struct p9_qid qid;
1001         int iounit;
1002
1003         P9_DPRINTK(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1004                                                 fid->fid, name, perm, mode);
1005         err = 0;
1006         clnt = fid->clnt;
1007
1008         if (fid->mode != -1)
1009                 return -EINVAL;
1010
1011         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1012                                 mode, extension);
1013         if (IS_ERR(req)) {
1014                 err = PTR_ERR(req);
1015                 goto error;
1016         }
1017
1018         err = p9pdu_readf(req->rc, clnt->dotu, "Qd", &qid, &iounit);
1019         if (err) {
1020                 p9pdu_dump(1, req->rc);
1021                 goto free_and_error;
1022         }
1023
1024         P9_DPRINTK(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1025                                 qid.type, qid.path, qid.version, iounit);
1026
1027         fid->mode = mode;
1028         fid->iounit = iounit;
1029
1030 free_and_error:
1031         p9_free_req(clnt, req);
1032 error:
1033         return err;
1034 }
1035 EXPORT_SYMBOL(p9_client_fcreate);
1036
1037 int p9_client_clunk(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, ">>> TCLUNK fid %d\n", fid->fid);
1044         err = 0;
1045         clnt = fid->clnt;
1046
1047         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1048         if (IS_ERR(req)) {
1049                 err = PTR_ERR(req);
1050                 goto error;
1051         }
1052
1053         P9_DPRINTK(P9_DEBUG_9P, "<<< RCLUNK 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_clunk);
1062
1063 int p9_client_remove(struct p9_fid *fid)
1064 {
1065         int err;
1066         struct p9_client *clnt;
1067         struct p9_req_t *req;
1068
1069         P9_DPRINTK(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1070         err = 0;
1071         clnt = fid->clnt;
1072
1073         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1074         if (IS_ERR(req)) {
1075                 err = PTR_ERR(req);
1076                 goto error;
1077         }
1078
1079         P9_DPRINTK(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1080
1081         p9_free_req(clnt, req);
1082         p9_fid_destroy(fid);
1083
1084 error:
1085         return err;
1086 }
1087 EXPORT_SYMBOL(p9_client_remove);
1088
1089 int
1090 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1091                                                                 u32 count)
1092 {
1093         int err, rsize, total;
1094         struct p9_client *clnt;
1095         struct p9_req_t *req;
1096         char *dataptr;
1097
1098         P9_DPRINTK(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n", fid->fid,
1099                                         (long long unsigned) offset, count);
1100         err = 0;
1101         clnt = fid->clnt;
1102         total = 0;
1103
1104         rsize = fid->iounit;
1105         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1106                 rsize = clnt->msize - P9_IOHDRSZ;
1107
1108         if (count < rsize)
1109                 rsize = count;
1110
1111         req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset, rsize);
1112         if (IS_ERR(req)) {
1113                 err = PTR_ERR(req);
1114                 goto error;
1115         }
1116
1117         err = p9pdu_readf(req->rc, clnt->dotu, "D", &count, &dataptr);
1118         if (err) {
1119                 p9pdu_dump(1, req->rc);
1120                 goto free_and_error;
1121         }
1122
1123         P9_DPRINTK(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1124
1125         if (data) {
1126                 memmove(data, dataptr, count);
1127                 data += count;
1128         }
1129
1130         if (udata) {
1131                 err = copy_to_user(udata, dataptr, count);
1132                 if (err) {
1133                         err = -EFAULT;
1134                         goto free_and_error;
1135                 }
1136         }
1137
1138         p9_free_req(clnt, req);
1139         return count;
1140
1141 free_and_error:
1142         p9_free_req(clnt, req);
1143 error:
1144         return err;
1145 }
1146 EXPORT_SYMBOL(p9_client_read);
1147
1148 int
1149 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1150                                                         u64 offset, u32 count)
1151 {
1152         int err, rsize, total;
1153         struct p9_client *clnt;
1154         struct p9_req_t *req;
1155
1156         P9_DPRINTK(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1157                                 fid->fid, (long long unsigned) offset, count);
1158         err = 0;
1159         clnt = fid->clnt;
1160         total = 0;
1161
1162         rsize = fid->iounit;
1163         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1164                 rsize = clnt->msize - P9_IOHDRSZ;
1165
1166         if (count < rsize)
1167                 rsize = count;
1168         if (data)
1169                 req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid, offset,
1170                                                                 rsize, data);
1171         else
1172                 req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid, offset,
1173                                                                 rsize, udata);
1174         if (IS_ERR(req)) {
1175                 err = PTR_ERR(req);
1176                 goto error;
1177         }
1178
1179         err = p9pdu_readf(req->rc, clnt->dotu, "d", &count);
1180         if (err) {
1181                 p9pdu_dump(1, req->rc);
1182                 goto free_and_error;
1183         }
1184
1185         P9_DPRINTK(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1186
1187         p9_free_req(clnt, req);
1188         return count;
1189
1190 free_and_error:
1191         p9_free_req(clnt, req);
1192 error:
1193         return err;
1194 }
1195 EXPORT_SYMBOL(p9_client_write);
1196
1197 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1198 {
1199         int err;
1200         struct p9_client *clnt;
1201         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1202         struct p9_req_t *req;
1203         u16 ignored;
1204
1205         P9_DPRINTK(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1206
1207         if (!ret)
1208                 return ERR_PTR(-ENOMEM);
1209
1210         err = 0;
1211         clnt = fid->clnt;
1212
1213         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1214         if (IS_ERR(req)) {
1215                 err = PTR_ERR(req);
1216                 goto error;
1217         }
1218
1219         err = p9pdu_readf(req->rc, clnt->dotu, "wS", &ignored, ret);
1220         if (err) {
1221                 ret = ERR_PTR(err);
1222                 p9pdu_dump(1, req->rc);
1223                 goto free_and_error;
1224         }
1225
1226         P9_DPRINTK(P9_DEBUG_9P,
1227                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1228                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1229                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1230                 "<<<    uid=%d gid=%d n_muid=%d\n",
1231                 ret->size, ret->type, ret->dev, ret->qid.type,
1232                 ret->qid.path, ret->qid.version, ret->mode,
1233                 ret->atime, ret->mtime, ret->length, ret->name,
1234                 ret->uid, ret->gid, ret->muid, ret->extension,
1235                 ret->n_uid, ret->n_gid, ret->n_muid);
1236
1237 free_and_error:
1238         p9_free_req(clnt, req);
1239 error:
1240         return ret;
1241 }
1242 EXPORT_SYMBOL(p9_client_stat);
1243
1244 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1245 {
1246         int err;
1247         struct p9_req_t *req;
1248         struct p9_client *clnt;
1249
1250         P9_DPRINTK(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1251         P9_DPRINTK(P9_DEBUG_9P,
1252                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1253                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1254                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1255                 "     uid=%d gid=%d n_muid=%d\n",
1256                 wst->size, wst->type, wst->dev, wst->qid.type,
1257                 wst->qid.path, wst->qid.version, wst->mode,
1258                 wst->atime, wst->mtime, wst->length, wst->name,
1259                 wst->uid, wst->gid, wst->muid, wst->extension,
1260                 wst->n_uid, wst->n_gid, wst->n_muid);
1261         err = 0;
1262         clnt = fid->clnt;
1263
1264         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, 0, wst);
1265         if (IS_ERR(req)) {
1266                 err = PTR_ERR(req);
1267                 goto error;
1268         }
1269
1270         P9_DPRINTK(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1271
1272         p9_free_req(clnt, req);
1273 error:
1274         return err;
1275 }
1276 EXPORT_SYMBOL(p9_client_wstat);