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 #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/slab.h>
  33 #include <linux/sched.h>
  34 #include <linux/uaccess.h>
  35 #include <net/9p/9p.h>
  36 #include <linux/parser.h>
  37 #include <net/9p/client.h>
  38 #include <net/9p/transport.h>
  39 #include "protocol.h"
  40
  41 /*
  42   * Client Option Parsing (code inspired by NFS code)
  43   *  - a little lazy - parse all client options
  44   */
  45
  46 enum {
  47         Opt_msize,
  48         Opt_trans,
  49         Opt_legacy,
  50         Opt_version,
  51         Opt_err,
  52 };
  53
  54 static const match_table_t tokens = {
  55         {Opt_msize, "msize=%u"},
  56         {Opt_legacy, "noextend"},
  57         {Opt_trans, "trans=%s"},
  58         {Opt_version, "version=%s"},
  59         {Opt_err, NULL},
  60 };
  61
  62 inline int p9_is_proto_dotl(struct p9_client *clnt)
  63 {
  64         return (clnt->proto_version == p9_proto_2000L);
  65 }
  66 EXPORT_SYMBOL(p9_is_proto_dotl);
  67
  68 inline int p9_is_proto_dotu(struct p9_client *clnt)
  69 {
  70         return (clnt->proto_version == p9_proto_2000u);
  71 }
  72 EXPORT_SYMBOL(p9_is_proto_dotu);
  73
  74 /* Interpret mount option for protocol version */
  75 static unsigned char get_protocol_version(const substring_t *name)
  76 {
  77         unsigned char version = -EINVAL;
  78         if (!strncmp("9p2000", name->from, name->to-name->from)) {
  79                 version = p9_proto_legacy;
  80                 P9_DPRINTK(P9_DEBUG_9P, "Protocol version: Legacy\n");
  81         } else if (!strncmp("9p2000.u", name->from, name->to-name->from)) {
  82                 version = p9_proto_2000u;
  83                 P9_DPRINTK(P9_DEBUG_9P, "Protocol version: 9P2000.u\n");
  84         } else if (!strncmp("9p2000.L", name->from, name->to-name->from)) {
  85                 version = p9_proto_2000L;
  86                 P9_DPRINTK(P9_DEBUG_9P, "Protocol version: 9P2000.L\n");
  87         } else {
  88                 P9_DPRINTK(P9_DEBUG_ERROR, "Unknown protocol version %s. ",
  89                                                         name->from);
  90         }
  91         return version;
  92 }
  93
  94 static struct p9_req_t *
  95 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...);
  96
  97 /**
  98  * parse_options - parse mount options into client structure
  99  * @opts: options string passed from mount
 100  * @clnt: existing v9fs client information
 101  *
 102  * Return 0 upon success, -ERRNO upon failure
 103  */
 104
 105 static int parse_opts(char *opts, struct p9_client *clnt)
 106 {
 107         char *options, *tmp_options;
 108         char *p;
 109         substring_t args[MAX_OPT_ARGS];
 110         int option;
 111         int ret = 0;
 112
 113         clnt->proto_version = p9_proto_2000u;
 114         clnt->msize = 8192;
 115
 116         if (!opts)
 117                 return 0;
 118
 119         tmp_options = kstrdup(opts, GFP_KERNEL);
 120         if (!tmp_options) {
 121                 P9_DPRINTK(P9_DEBUG_ERROR,
 122                                 "failed to allocate copy of option string\n");
 123                 return -ENOMEM;
 124         }
 125         options = tmp_options;
 126
 127         while ((p = strsep(&options, ",")) != NULL) {
 128                 int token;
 129                 if (!*p)
 130                         continue;
 131                 token = match_token(p, tokens, args);
 132                 if (token < Opt_trans) {
 133                         int r = match_int(&args[0], &option);
 134                         if (r < 0) {
 135                                 P9_DPRINTK(P9_DEBUG_ERROR,
 136                                         "integer field, but no integer?\n");
 137                                 ret = r;
 138                                 continue;
 139                         }
 140                 }
 141                 switch (token) {
 142                 case Opt_msize:
 143                         clnt->msize = option;
 144                         break;
 145                 case Opt_trans:
 146                         clnt->trans_mod = v9fs_get_trans_by_name(&args[0]);
 147                         if(clnt->trans_mod == NULL) {
 148                                 P9_DPRINTK(P9_DEBUG_ERROR,
 149                                    "Could not find request transport: %s\n",
 150                                    (char *) &args[0]);
 151                                 ret = -EINVAL;
 152                                 goto free_and_return;
 153                         }
 154                         break;
 155                 case Opt_legacy:
 156                         clnt->proto_version = p9_proto_legacy;
 157                         break;
 158                 case Opt_version:
 159                         ret = get_protocol_version(&args[0]);
 160                         if (ret == -EINVAL)
 161                                 goto free_and_return;
 162                         clnt->proto_version = ret;
 163                         break;
 164                 default:
 165                         continue;
 166                 }
 167         }
 168
 169 free_and_return:
 170         kfree(tmp_options);
 171         return ret;
 172 }
 173
 174 /**
 175  * p9_tag_alloc - lookup/allocate a request by tag
 176  * @c: client session to lookup tag within
 177  * @tag: numeric id for transaction
 178  *
 179  * this is a simple array lookup, but will grow the
 180  * request_slots as necessary to accomodate transaction
 181  * ids which did not previously have a slot.
 182  *
 183  * this code relies on the client spinlock to manage locks, its
 184  * possible we should switch to something else, but I'd rather
 185  * stick with something low-overhead for the common case.
 186  *
 187  */
 188
 189 static struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag)
 190 {
 191         unsigned long flags;
 192         int row, col;
 193         struct p9_req_t *req;
 194
 195         /* This looks up the original request by tag so we know which
 196          * buffer to read the data into */
 197         tag++;
 198
 199         if (tag >= c->max_tag) {
 200                 spin_lock_irqsave(&c->lock, flags);
 201                 /* check again since original check was outside of lock */
 202                 while (tag >= c->max_tag) {
 203                         row = (tag / P9_ROW_MAXTAG);
 204                         c->reqs[row] = kcalloc(P9_ROW_MAXTAG,
 205                                         sizeof(struct p9_req_t), GFP_ATOMIC);
 206
 207                         if (!c->reqs[row]) {
 208                                 printk(KERN_ERR "Couldn't grow tag array\n");
 209                                 spin_unlock_irqrestore(&c->lock, flags);
 210                                 return ERR_PTR(-ENOMEM);
 211                         }
 212                         for (col = 0; col < P9_ROW_MAXTAG; col++) {
 213                                 c->reqs[row][col].status = REQ_STATUS_IDLE;
 214                                 c->reqs[row][col].tc = NULL;
 215                         }
 216                         c->max_tag += P9_ROW_MAXTAG;
 217                 }
 218                 spin_unlock_irqrestore(&c->lock, flags);
 219         }
 220         row = tag / P9_ROW_MAXTAG;
 221         col = tag % P9_ROW_MAXTAG;
 222
 223         req = &c->reqs[row][col];
 224         if (!req->tc) {
 225                 req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_KERNEL);
 226                 if (!req->wq) {
 227                         printk(KERN_ERR "Couldn't grow tag array\n");
 228                         return ERR_PTR(-ENOMEM);
 229                 }
 230                 init_waitqueue_head(req->wq);
 231                 req->tc = kmalloc(sizeof(struct p9_fcall)+c->msize,
 232                                                                 GFP_KERNEL);
 233                 req->rc = kmalloc(sizeof(struct p9_fcall)+c->msize,
 234                                                                 GFP_KERNEL);
 235                 if ((!req->tc) || (!req->rc)) {
 236                         printk(KERN_ERR "Couldn't grow tag array\n");
 237                         kfree(req->tc);
 238                         kfree(req->rc);
 239                         kfree(req->wq);
 240                         req->tc = req->rc = NULL;
 241                         req->wq = NULL;
 242                         return ERR_PTR(-ENOMEM);
 243                 }
 244                 req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
 245                 req->tc->capacity = c->msize;
 246                 req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall);
 247                 req->rc->capacity = c->msize;
 248         }
 249
 250         p9pdu_reset(req->tc);
 251         p9pdu_reset(req->rc);
 252
 253         req->tc->tag = tag-1;
 254         req->status = REQ_STATUS_ALLOC;
 255
 256         return &c->reqs[row][col];
 257 }
 258
 259 /**
 260  * p9_tag_lookup - lookup a request by tag
 261  * @c: client session to lookup tag within
 262  * @tag: numeric id for transaction
 263  *
 264  */
 265
 266 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag)
 267 {
 268         int row, col;
 269
 270         /* This looks up the original request by tag so we know which
 271          * buffer to read the data into */
 272         tag++;
 273
 274         BUG_ON(tag >= c->max_tag);
 275
 276         row = tag / P9_ROW_MAXTAG;
 277         col = tag % P9_ROW_MAXTAG;
 278
 279         return &c->reqs[row][col];
 280 }
 281 EXPORT_SYMBOL(p9_tag_lookup);
 282
 283 /**
 284  * p9_tag_init - setup tags structure and contents
 285  * @c:  v9fs client struct
 286  *
 287  * This initializes the tags structure for each client instance.
 288  *
 289  */
 290
 291 static int p9_tag_init(struct p9_client *c)
 292 {
 293         int err = 0;
 294
 295         c->tagpool = p9_idpool_create();
 296         if (IS_ERR(c->tagpool)) {
 297                 err = PTR_ERR(c->tagpool);
 298                 c->tagpool = NULL;
 299                 goto error;
 300         }
 301
 302         p9_idpool_get(c->tagpool); /* reserve tag 0 */
 303
 304         c->max_tag = 0;
 305 error:
 306         return err;
 307 }
 308
 309 /**
 310  * p9_tag_cleanup - cleans up tags structure and reclaims resources
 311  * @c:  v9fs client struct
 312  *
 313  * This frees resources associated with the tags structure
 314  *
 315  */
 316 static void p9_tag_cleanup(struct p9_client *c)
 317 {
 318         int row, col;
 319
 320         /* check to insure all requests are idle */
 321         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 322                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 323                         if (c->reqs[row][col].status != REQ_STATUS_IDLE) {
 324                                 P9_DPRINTK(P9_DEBUG_MUX,
 325                                   "Attempting to cleanup non-free tag %d,%d\n",
 326                                   row, col);
 327                                 /* TODO: delay execution of cleanup */
 328                                 return;
 329                         }
 330                 }
 331         }
 332
 333         if (c->tagpool)
 334                 p9_idpool_destroy(c->tagpool);
 335
 336         /* free requests associated with tags */
 337         for (row = 0; row < (c->max_tag/P9_ROW_MAXTAG); row++) {
 338                 for (col = 0; col < P9_ROW_MAXTAG; col++) {
 339                         kfree(c->reqs[row][col].wq);
 340                         kfree(c->reqs[row][col].tc);
 341                         kfree(c->reqs[row][col].rc);
 342                 }
 343                 kfree(c->reqs[row]);
 344         }
 345         c->max_tag = 0;
 346 }
 347
 348 /**
 349  * p9_free_req - free a request and clean-up as necessary
 350  * c: client state
 351  * r: request to release
 352  *
 353  */
 354
 355 static void p9_free_req(struct p9_client *c, struct p9_req_t *r)
 356 {
 357         int tag = r->tc->tag;
 358         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p req %p tag: %d\n", c, r, tag);
 359
 360         r->status = REQ_STATUS_IDLE;
 361         if (tag != P9_NOTAG && p9_idpool_check(tag, c->tagpool))
 362                 p9_idpool_put(tag, c->tagpool);
 363 }
 364
 365 /**
 366  * p9_client_cb - call back from transport to client
 367  * c: client state
 368  * req: request received
 369  *
 370  */
 371 void p9_client_cb(struct p9_client *c, struct p9_req_t *req)
 372 {
 373         P9_DPRINTK(P9_DEBUG_MUX, " tag %d\n", req->tc->tag);
 374         wake_up(req->wq);
 375         P9_DPRINTK(P9_DEBUG_MUX, "wakeup: %d\n", req->tc->tag);
 376 }
 377 EXPORT_SYMBOL(p9_client_cb);
 378
 379 /**
 380  * p9_parse_header - parse header arguments out of a packet
 381  * @pdu: packet to parse
 382  * @size: size of packet
 383  * @type: type of request
 384  * @tag: tag of packet
 385  * @rewind: set if we need to rewind offset afterwards
 386  */
 387
 388 int
 389 p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag,
 390                                                                 int rewind)
 391 {
 392         int8_t r_type;
 393         int16_t r_tag;
 394         int32_t r_size;
 395         int offset = pdu->offset;
 396         int err;
 397
 398         pdu->offset = 0;
 399         if (pdu->size == 0)
 400                 pdu->size = 7;
 401
 402         err = p9pdu_readf(pdu, 0, "dbw", &r_size, &r_type, &r_tag);
 403         if (err)
 404                 goto rewind_and_exit;
 405
 406         pdu->size = r_size;
 407         pdu->id = r_type;
 408         pdu->tag = r_tag;
 409
 410         P9_DPRINTK(P9_DEBUG_9P, "<<< size=%d type: %d tag: %d\n", pdu->size,
 411                                                         pdu->id, pdu->tag);
 412
 413         if (type)
 414                 *type = r_type;
 415         if (tag)
 416                 *tag = r_tag;
 417         if (size)
 418                 *size = r_size;
 419
 420
 421 rewind_and_exit:
 422         if (rewind)
 423                 pdu->offset = offset;
 424         return err;
 425 }
 426 EXPORT_SYMBOL(p9_parse_header);
 427
 428 /**
 429  * p9_check_errors - check 9p packet for error return and process it
 430  * @c: current client instance
 431  * @req: request to parse and check for error conditions
 432  *
 433  * returns error code if one is discovered, otherwise returns 0
 434  *
 435  * this will have to be more complicated if we have multiple
 436  * error packet types
 437  */
 438
 439 static int p9_check_errors(struct p9_client *c, struct p9_req_t *req)
 440 {
 441         int8_t type;
 442         int err;
 443
 444         err = p9_parse_header(req->rc, NULL, &type, NULL, 0);
 445         if (err) {
 446                 P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse header %d\n", err);
 447                 return err;
 448         }
 449
 450         if (type == P9_RERROR) {
 451                 int ecode;
 452                 char *ename;
 453
 454                 err = p9pdu_readf(req->rc, c->proto_version, "s?d",
 455                                                         &ename, &ecode);
 456                 if (err) {
 457                         P9_DPRINTK(P9_DEBUG_ERROR, "couldn't parse error%d\n",
 458                                                                         err);
 459                         return err;
 460                 }
 461
 462                 if (p9_is_proto_dotu(c))
 463                         err = -ecode;
 464
 465                 if (!err || !IS_ERR_VALUE(err))
 466                         err = p9_errstr2errno(ename, strlen(ename));
 467
 468                 P9_DPRINTK(P9_DEBUG_9P, "<<< RERROR (%d) %s\n", -ecode, ename);
 469
 470                 kfree(ename);
 471         } else
 472                 err = 0;
 473
 474         return err;
 475 }
 476
 477 /**
 478  * p9_client_flush - flush (cancel) a request
 479  * @c: client state
 480  * @oldreq: request to cancel
 481  *
 482  * This sents a flush for a particular requests and links
 483  * the flush request to the original request.  The current
 484  * code only supports a single flush request although the protocol
 485  * allows for multiple flush requests to be sent for a single request.
 486  *
 487  */
 488
 489 static int p9_client_flush(struct p9_client *c, struct p9_req_t *oldreq)
 490 {
 491         struct p9_req_t *req;
 492         int16_t oldtag;
 493         int err;
 494
 495         err = p9_parse_header(oldreq->tc, NULL, NULL, &oldtag, 1);
 496         if (err)
 497                 return err;
 498
 499         P9_DPRINTK(P9_DEBUG_9P, ">>> TFLUSH tag %d\n", oldtag);
 500
 501         req = p9_client_rpc(c, P9_TFLUSH, "w", oldtag);
 502         if (IS_ERR(req))
 503                 return PTR_ERR(req);
 504
 505
 506         /* if we haven't received a response for oldreq,
 507            remove it from the list. */
 508         spin_lock(&c->lock);
 509         if (oldreq->status == REQ_STATUS_FLSH)
 510                 list_del(&oldreq->req_list);
 511         spin_unlock(&c->lock);
 512
 513         p9_free_req(c, req);
 514         return 0;
 515 }
 516
 517 /**
 518  * p9_client_rpc - issue a request and wait for a response
 519  * @c: client session
 520  * @type: type of request
 521  * @fmt: protocol format string (see protocol.c)
 522  *
 523  * Returns request structure (which client must free using p9_free_req)
 524  */
 525
 526 static struct p9_req_t *
 527 p9_client_rpc(struct p9_client *c, int8_t type, const char *fmt, ...)
 528 {
 529         va_list ap;
 530         int tag, err;
 531         struct p9_req_t *req;
 532         unsigned long flags;
 533         int sigpending;
 534
 535         P9_DPRINTK(P9_DEBUG_MUX, "client %p op %d\n", c, type);
 536
 537         if (c->status != Connected)
 538                 return ERR_PTR(-EIO);
 539
 540         if (signal_pending(current)) {
 541                 sigpending = 1;
 542                 clear_thread_flag(TIF_SIGPENDING);
 543         } else
 544                 sigpending = 0;
 545
 546         tag = P9_NOTAG;
 547         if (type != P9_TVERSION) {
 548                 tag = p9_idpool_get(c->tagpool);
 549                 if (tag < 0)
 550                         return ERR_PTR(-ENOMEM);
 551         }
 552
 553         req = p9_tag_alloc(c, tag);
 554         if (IS_ERR(req))
 555                 return req;
 556
 557         /* marshall the data */
 558         p9pdu_prepare(req->tc, tag, type);
 559         va_start(ap, fmt);
 560         err = p9pdu_vwritef(req->tc, c->proto_version, fmt, ap);
 561         va_end(ap);
 562         p9pdu_finalize(req->tc);
 563
 564         err = c->trans_mod->request(c, req);
 565         if (err < 0) {
 566                 c->status = Disconnected;
 567                 goto reterr;
 568         }
 569
 570         P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d\n", req->wq, tag);
 571         err = wait_event_interruptible(*req->wq,
 572                                                 req->status >= REQ_STATUS_RCVD);
 573         P9_DPRINTK(P9_DEBUG_MUX, "wait %p tag: %d returned %d\n",
 574                                                 req->wq, tag, err);
 575
 576         if (req->status == REQ_STATUS_ERROR) {
 577                 P9_DPRINTK(P9_DEBUG_ERROR, "req_status error %d\n", req->t_err);
 578                 err = req->t_err;
 579         }
 580
 581         if ((err == -ERESTARTSYS) && (c->status == Connected)) {
 582                 P9_DPRINTK(P9_DEBUG_MUX, "flushing\n");
 583                 sigpending = 1;
 584                 clear_thread_flag(TIF_SIGPENDING);
 585
 586                 if (c->trans_mod->cancel(c, req))
 587                         p9_client_flush(c, req);
 588
 589                 /* if we received the response anyway, don't signal error */
 590                 if (req->status == REQ_STATUS_RCVD)
 591                         err = 0;
 592         }
 593
 594         if (sigpending) {
 595                 spin_lock_irqsave(&current->sighand->siglock, flags);
 596                 recalc_sigpending();
 597                 spin_unlock_irqrestore(&current->sighand->siglock, flags);
 598         }
 599
 600         if (err < 0)
 601                 goto reterr;
 602
 603         err = p9_check_errors(c, req);
 604         if (!err) {
 605                 P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d\n", c, type);
 606                 return req;
 607         }
 608
 609 reterr:
 610         P9_DPRINTK(P9_DEBUG_MUX, "exit: client %p op %d error: %d\n", c, type,
 611                                                                         err);
 612         p9_free_req(c, req);
 613         return ERR_PTR(err);
 614 }
 615
 616 static struct p9_fid *p9_fid_create(struct p9_client *clnt)
 617 {
 618         int ret;
 619         struct p9_fid *fid;
 620         unsigned long flags;
 621
 622         P9_DPRINTK(P9_DEBUG_FID, "clnt %p\n", clnt);
 623         fid = kmalloc(sizeof(struct p9_fid), GFP_KERNEL);
 624         if (!fid)
 625                 return ERR_PTR(-ENOMEM);
 626
 627         ret = p9_idpool_get(clnt->fidpool);
 628         if (ret < 0) {
 629                 ret = -ENOSPC;
 630                 goto error;
 631         }
 632         fid->fid = ret;
 633
 634         memset(&fid->qid, 0, sizeof(struct p9_qid));
 635         fid->mode = -1;
 636         fid->uid = current_fsuid();
 637         fid->clnt = clnt;
 638         fid->rdir = NULL;
 639         spin_lock_irqsave(&clnt->lock, flags);
 640         list_add(&fid->flist, &clnt->fidlist);
 641         spin_unlock_irqrestore(&clnt->lock, flags);
 642
 643         return fid;
 644
 645 error:
 646         kfree(fid);
 647         return ERR_PTR(ret);
 648 }
 649
 650 static void p9_fid_destroy(struct p9_fid *fid)
 651 {
 652         struct p9_client *clnt;
 653         unsigned long flags;
 654
 655         P9_DPRINTK(P9_DEBUG_FID, "fid %d\n", fid->fid);
 656         clnt = fid->clnt;
 657         p9_idpool_put(fid->fid, clnt->fidpool);
 658         spin_lock_irqsave(&clnt->lock, flags);
 659         list_del(&fid->flist);
 660         spin_unlock_irqrestore(&clnt->lock, flags);
 661         kfree(fid->rdir);
 662         kfree(fid);
 663 }
 664
 665 int p9_client_version(struct p9_client *c)
 666 {
 667         int err = 0;
 668         struct p9_req_t *req;
 669         char *version;
 670         int msize;
 671
 672         P9_DPRINTK(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",
 673                                                 c->msize, c->proto_version);
 674
 675         switch (c->proto_version) {
 676         case p9_proto_2000L:
 677                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 678                                         c->msize, "9P2000.L");
 679                 break;
 680         case p9_proto_2000u:
 681                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 682                                         c->msize, "9P2000.u");
 683                 break;
 684         case p9_proto_legacy:
 685                 req = p9_client_rpc(c, P9_TVERSION, "ds",
 686                                         c->msize, "9P2000");
 687                 break;
 688         default:
 689                 return -EINVAL;
 690                 break;
 691         }
 692
 693         if (IS_ERR(req))
 694                 return PTR_ERR(req);
 695
 696         err = p9pdu_readf(req->rc, c->proto_version, "ds", &msize, &version);
 697         if (err) {
 698                 P9_DPRINTK(P9_DEBUG_9P, "version error %d\n", err);
 699                 p9pdu_dump(1, req->rc);
 700                 goto error;
 701         }
 702
 703         P9_DPRINTK(P9_DEBUG_9P, "<<< RVERSION msize %d %s\n", msize, version);
 704         if (!strncmp(version, "9P2000.L", 8))
 705                 c->proto_version = p9_proto_2000L;
 706         else if (!strncmp(version, "9P2000.u", 8))
 707                 c->proto_version = p9_proto_2000u;
 708         else if (!strncmp(version, "9P2000", 6))
 709                 c->proto_version = p9_proto_legacy;
 710         else {
 711                 err = -EREMOTEIO;
 712                 goto error;
 713         }
 714
 715         if (msize < c->msize)
 716                 c->msize = msize;
 717
 718 error:
 719         kfree(version);
 720         p9_free_req(c, req);
 721
 722         return err;
 723 }
 724 EXPORT_SYMBOL(p9_client_version);
 725
 726 struct p9_client *p9_client_create(const char *dev_name, char *options)
 727 {
 728         int err;
 729         struct p9_client *clnt;
 730
 731         err = 0;
 732         clnt = kmalloc(sizeof(struct p9_client), GFP_KERNEL);
 733         if (!clnt)
 734                 return ERR_PTR(-ENOMEM);
 735
 736         clnt->trans_mod = NULL;
 737         clnt->trans = NULL;
 738         spin_lock_init(&clnt->lock);
 739         INIT_LIST_HEAD(&clnt->fidlist);
 740
 741         p9_tag_init(clnt);
 742
 743         err = parse_opts(options, clnt);
 744         if (err < 0)
 745                 goto free_client;
 746
 747         if (!clnt->trans_mod)
 748                 clnt->trans_mod = v9fs_get_default_trans();
 749
 750         if (clnt->trans_mod == NULL) {
 751                 err = -EPROTONOSUPPORT;
 752                 P9_DPRINTK(P9_DEBUG_ERROR,
 753                                 "No transport defined or default transport\n");
 754                 goto free_client;
 755         }
 756
 757         clnt->fidpool = p9_idpool_create();
 758         if (IS_ERR(clnt->fidpool)) {
 759                 err = PTR_ERR(clnt->fidpool);
 760                 clnt->fidpool = NULL;
 761                 goto put_trans;
 762         }
 763
 764         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n",
 765                 clnt, clnt->trans_mod, clnt->msize, clnt->proto_version);
 766
 767         err = clnt->trans_mod->create(clnt, dev_name, options);
 768         if (err)
 769                 goto destroy_fidpool;
 770
 771         if ((clnt->msize+P9_IOHDRSZ) > clnt->trans_mod->maxsize)
 772                 clnt->msize = clnt->trans_mod->maxsize-P9_IOHDRSZ;
 773
 774         err = p9_client_version(clnt);
 775         if (err)
 776                 goto close_trans;
 777
 778         return clnt;
 779
 780 close_trans:
 781         clnt->trans_mod->close(clnt);
 782 destroy_fidpool:
 783         p9_idpool_destroy(clnt->fidpool);
 784 put_trans:
 785         v9fs_put_trans(clnt->trans_mod);
 786 free_client:
 787         kfree(clnt);
 788         return ERR_PTR(err);
 789 }
 790 EXPORT_SYMBOL(p9_client_create);
 791
 792 void p9_client_destroy(struct p9_client *clnt)
 793 {
 794         struct p9_fid *fid, *fidptr;
 795
 796         P9_DPRINTK(P9_DEBUG_MUX, "clnt %p\n", clnt);
 797
 798         if (clnt->trans_mod)
 799                 clnt->trans_mod->close(clnt);
 800
 801         v9fs_put_trans(clnt->trans_mod);
 802
 803         list_for_each_entry_safe(fid, fidptr, &clnt->fidlist, flist)
 804                 p9_fid_destroy(fid);
 805
 806         if (clnt->fidpool)
 807                 p9_idpool_destroy(clnt->fidpool);
 808
 809         p9_tag_cleanup(clnt);
 810
 811         kfree(clnt);
 812 }
 813 EXPORT_SYMBOL(p9_client_destroy);
 814
 815 void p9_client_disconnect(struct p9_client *clnt)
 816 {
 817         P9_DPRINTK(P9_DEBUG_9P, "clnt %p\n", clnt);
 818         clnt->status = Disconnected;
 819 }
 820 EXPORT_SYMBOL(p9_client_disconnect);
 821
 822 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
 823         char *uname, u32 n_uname, char *aname)
 824 {
 825         int err;
 826         struct p9_req_t *req;
 827         struct p9_fid *fid;
 828         struct p9_qid qid;
 829
 830         P9_DPRINTK(P9_DEBUG_9P, ">>> TATTACH afid %d uname %s aname %s\n",
 831                                         afid ? afid->fid : -1, uname, aname);
 832         err = 0;
 833
 834         fid = p9_fid_create(clnt);
 835         if (IS_ERR(fid)) {
 836                 err = PTR_ERR(fid);
 837                 fid = NULL;
 838                 goto error;
 839         }
 840
 841         req = p9_client_rpc(clnt, P9_TATTACH, "ddss?d", fid->fid,
 842                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
 843         if (IS_ERR(req)) {
 844                 err = PTR_ERR(req);
 845                 goto error;
 846         }
 847
 848         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
 849         if (err) {
 850                 p9pdu_dump(1, req->rc);
 851                 p9_free_req(clnt, req);
 852                 goto error;
 853         }
 854
 855         P9_DPRINTK(P9_DEBUG_9P, "<<< RATTACH qid %x.%llx.%x\n",
 856                                         qid.type,
 857                                         (unsigned long long)qid.path,
 858                                         qid.version);
 859
 860         memmove(&fid->qid, &qid, sizeof(struct p9_qid));
 861
 862         p9_free_req(clnt, req);
 863         return fid;
 864
 865 error:
 866         if (fid)
 867                 p9_fid_destroy(fid);
 868         return ERR_PTR(err);
 869 }
 870 EXPORT_SYMBOL(p9_client_attach);
 871
 872 struct p9_fid *
 873 p9_client_auth(struct p9_client *clnt, char *uname, u32 n_uname, char *aname)
 874 {
 875         int err;
 876         struct p9_req_t *req;
 877         struct p9_qid qid;
 878         struct p9_fid *afid;
 879
 880         P9_DPRINTK(P9_DEBUG_9P, ">>> TAUTH uname %s aname %s\n", uname, aname);
 881         err = 0;
 882
 883         afid = p9_fid_create(clnt);
 884         if (IS_ERR(afid)) {
 885                 err = PTR_ERR(afid);
 886                 afid = NULL;
 887                 goto error;
 888         }
 889
 890         req = p9_client_rpc(clnt, P9_TAUTH, "dss?d",
 891                         afid ? afid->fid : P9_NOFID, uname, aname, n_uname);
 892         if (IS_ERR(req)) {
 893                 err = PTR_ERR(req);
 894                 goto error;
 895         }
 896
 897         err = p9pdu_readf(req->rc, clnt->proto_version, "Q", &qid);
 898         if (err) {
 899                 p9pdu_dump(1, req->rc);
 900                 p9_free_req(clnt, req);
 901                 goto error;
 902         }
 903
 904         P9_DPRINTK(P9_DEBUG_9P, "<<< RAUTH qid %x.%llx.%x\n",
 905                                         qid.type,
 906                                         (unsigned long long)qid.path,
 907                                         qid.version);
 908
 909         memmove(&afid->qid, &qid, sizeof(struct p9_qid));
 910         p9_free_req(clnt, req);
 911         return afid;
 912
 913 error:
 914         if (afid)
 915                 p9_fid_destroy(afid);
 916         return ERR_PTR(err);
 917 }
 918 EXPORT_SYMBOL(p9_client_auth);
 919
 920 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, int nwname, char **wnames,
 921         int clone)
 922 {
 923         int err;
 924         struct p9_client *clnt;
 925         struct p9_fid *fid;
 926         struct p9_qid *wqids;
 927         struct p9_req_t *req;
 928         int16_t nwqids, count;
 929
 930         err = 0;
 931         clnt = oldfid->clnt;
 932         if (clone) {
 933                 fid = p9_fid_create(clnt);
 934                 if (IS_ERR(fid)) {
 935                         err = PTR_ERR(fid);
 936                         fid = NULL;
 937                         goto error;
 938                 }
 939
 940                 fid->uid = oldfid->uid;
 941         } else
 942                 fid = oldfid;
 943
 944
 945         P9_DPRINTK(P9_DEBUG_9P, ">>> TWALK fids %d,%d nwname %d wname[0] %s\n",
 946                 oldfid->fid, fid->fid, nwname, wnames ? wnames[0] : NULL);
 947
 948         req = p9_client_rpc(clnt, P9_TWALK, "ddT", oldfid->fid, fid->fid,
 949                                                                 nwname, wnames);
 950         if (IS_ERR(req)) {
 951                 err = PTR_ERR(req);
 952                 goto error;
 953         }
 954
 955         err = p9pdu_readf(req->rc, clnt->proto_version, "R", &nwqids, &wqids);
 956         if (err) {
 957                 p9pdu_dump(1, req->rc);
 958                 p9_free_req(clnt, req);
 959                 goto clunk_fid;
 960         }
 961         p9_free_req(clnt, req);
 962
 963         P9_DPRINTK(P9_DEBUG_9P, "<<< RWALK nwqid %d:\n", nwqids);
 964
 965         if (nwqids != nwname) {
 966                 err = -ENOENT;
 967                 goto clunk_fid;
 968         }
 969
 970         for (count = 0; count < nwqids; count++)
 971                 P9_DPRINTK(P9_DEBUG_9P, "<<<     [%d] %x.%llx.%x\n",
 972                         count, wqids[count].type,
 973                         (unsigned long long)wqids[count].path,
 974                         wqids[count].version);
 975
 976         if (nwname)
 977                 memmove(&fid->qid, &wqids[nwqids - 1], sizeof(struct p9_qid));
 978         else
 979                 fid->qid = oldfid->qid;
 980
 981         return fid;
 982
 983 clunk_fid:
 984         p9_client_clunk(fid);
 985         fid = NULL;
 986
 987 error:
 988         if (fid && (fid != oldfid))
 989                 p9_fid_destroy(fid);
 990
 991         return ERR_PTR(err);
 992 }
 993 EXPORT_SYMBOL(p9_client_walk);
 994
 995 int p9_client_open(struct p9_fid *fid, int mode)
 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, ">>> TOPEN fid %d mode %d\n", fid->fid, mode);
1004         err = 0;
1005         clnt = fid->clnt;
1006
1007         if (fid->mode != -1)
1008                 return -EINVAL;
1009
1010         req = p9_client_rpc(clnt, P9_TOPEN, "db", fid->fid, mode);
1011         if (IS_ERR(req)) {
1012                 err = PTR_ERR(req);
1013                 goto error;
1014         }
1015
1016         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1017         if (err) {
1018                 p9pdu_dump(1, req->rc);
1019                 goto free_and_error;
1020         }
1021
1022         P9_DPRINTK(P9_DEBUG_9P, "<<< ROPEN qid %x.%llx.%x iounit %x\n",
1023                                 qid.type,
1024                                 (unsigned long long)qid.path,
1025                                 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_open);
1036
1037 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
1038                      char *extension)
1039 {
1040         int err;
1041         struct p9_client *clnt;
1042         struct p9_req_t *req;
1043         struct p9_qid qid;
1044         int iounit;
1045
1046         P9_DPRINTK(P9_DEBUG_9P, ">>> TCREATE fid %d name %s perm %d mode %d\n",
1047                                                 fid->fid, name, perm, mode);
1048         err = 0;
1049         clnt = fid->clnt;
1050
1051         if (fid->mode != -1)
1052                 return -EINVAL;
1053
1054         req = p9_client_rpc(clnt, P9_TCREATE, "dsdb?s", fid->fid, name, perm,
1055                                 mode, extension);
1056         if (IS_ERR(req)) {
1057                 err = PTR_ERR(req);
1058                 goto error;
1059         }
1060
1061         err = p9pdu_readf(req->rc, clnt->proto_version, "Qd", &qid, &iounit);
1062         if (err) {
1063                 p9pdu_dump(1, req->rc);
1064                 goto free_and_error;
1065         }
1066
1067         P9_DPRINTK(P9_DEBUG_9P, "<<< RCREATE qid %x.%llx.%x iounit %x\n",
1068                                 qid.type,
1069                                 (unsigned long long)qid.path,
1070                                 qid.version, iounit);
1071
1072         fid->mode = mode;
1073         fid->iounit = iounit;
1074
1075 free_and_error:
1076         p9_free_req(clnt, req);
1077 error:
1078         return err;
1079 }
1080 EXPORT_SYMBOL(p9_client_fcreate);
1081
1082 int p9_client_clunk(struct p9_fid *fid)
1083 {
1084         int err;
1085         struct p9_client *clnt;
1086         struct p9_req_t *req;
1087
1088         P9_DPRINTK(P9_DEBUG_9P, ">>> TCLUNK fid %d\n", fid->fid);
1089         err = 0;
1090         clnt = fid->clnt;
1091
1092         req = p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid);
1093         if (IS_ERR(req)) {
1094                 err = PTR_ERR(req);
1095                 goto error;
1096         }
1097
1098         P9_DPRINTK(P9_DEBUG_9P, "<<< RCLUNK fid %d\n", fid->fid);
1099
1100         p9_free_req(clnt, req);
1101         p9_fid_destroy(fid);
1102
1103 error:
1104         return err;
1105 }
1106 EXPORT_SYMBOL(p9_client_clunk);
1107
1108 int p9_client_remove(struct p9_fid *fid)
1109 {
1110         int err;
1111         struct p9_client *clnt;
1112         struct p9_req_t *req;
1113
1114         P9_DPRINTK(P9_DEBUG_9P, ">>> TREMOVE fid %d\n", fid->fid);
1115         err = 0;
1116         clnt = fid->clnt;
1117
1118         req = p9_client_rpc(clnt, P9_TREMOVE, "d", fid->fid);
1119         if (IS_ERR(req)) {
1120                 err = PTR_ERR(req);
1121                 goto error;
1122         }
1123
1124         P9_DPRINTK(P9_DEBUG_9P, "<<< RREMOVE fid %d\n", fid->fid);
1125
1126         p9_free_req(clnt, req);
1127         p9_fid_destroy(fid);
1128
1129 error:
1130         return err;
1131 }
1132 EXPORT_SYMBOL(p9_client_remove);
1133
1134 int
1135 p9_client_read(struct p9_fid *fid, char *data, char __user *udata, u64 offset,
1136                                                                 u32 count)
1137 {
1138         int err, rsize, total;
1139         struct p9_client *clnt;
1140         struct p9_req_t *req;
1141         char *dataptr;
1142
1143         P9_DPRINTK(P9_DEBUG_9P, ">>> TREAD fid %d offset %llu %d\n", fid->fid,
1144                                         (long long unsigned) offset, count);
1145         err = 0;
1146         clnt = fid->clnt;
1147         total = 0;
1148
1149         rsize = fid->iounit;
1150         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1151                 rsize = clnt->msize - P9_IOHDRSZ;
1152
1153         if (count < rsize)
1154                 rsize = count;
1155
1156         req = p9_client_rpc(clnt, P9_TREAD, "dqd", fid->fid, offset, rsize);
1157         if (IS_ERR(req)) {
1158                 err = PTR_ERR(req);
1159                 goto error;
1160         }
1161
1162         err = p9pdu_readf(req->rc, clnt->proto_version, "D", &count, &dataptr);
1163         if (err) {
1164                 p9pdu_dump(1, req->rc);
1165                 goto free_and_error;
1166         }
1167
1168         P9_DPRINTK(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
1169
1170         if (data) {
1171                 memmove(data, dataptr, count);
1172         }
1173
1174         if (udata) {
1175                 err = copy_to_user(udata, dataptr, count);
1176                 if (err) {
1177                         err = -EFAULT;
1178                         goto free_and_error;
1179                 }
1180         }
1181
1182         p9_free_req(clnt, req);
1183         return count;
1184
1185 free_and_error:
1186         p9_free_req(clnt, req);
1187 error:
1188         return err;
1189 }
1190 EXPORT_SYMBOL(p9_client_read);
1191
1192 int
1193 p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
1194                                                         u64 offset, u32 count)
1195 {
1196         int err, rsize, total;
1197         struct p9_client *clnt;
1198         struct p9_req_t *req;
1199
1200         P9_DPRINTK(P9_DEBUG_9P, ">>> TWRITE fid %d offset %llu count %d\n",
1201                                 fid->fid, (long long unsigned) offset, count);
1202         err = 0;
1203         clnt = fid->clnt;
1204         total = 0;
1205
1206         rsize = fid->iounit;
1207         if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
1208                 rsize = clnt->msize - P9_IOHDRSZ;
1209
1210         if (count < rsize)
1211                 rsize = count;
1212         if (data)
1213                 req = p9_client_rpc(clnt, P9_TWRITE, "dqD", fid->fid, offset,
1214                                                                 rsize, data);
1215         else
1216                 req = p9_client_rpc(clnt, P9_TWRITE, "dqU", fid->fid, offset,
1217                                                                 rsize, udata);
1218         if (IS_ERR(req)) {
1219                 err = PTR_ERR(req);
1220                 goto error;
1221         }
1222
1223         err = p9pdu_readf(req->rc, clnt->proto_version, "d", &count);
1224         if (err) {
1225                 p9pdu_dump(1, req->rc);
1226                 goto free_and_error;
1227         }
1228
1229         P9_DPRINTK(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
1230
1231         p9_free_req(clnt, req);
1232         return count;
1233
1234 free_and_error:
1235         p9_free_req(clnt, req);
1236 error:
1237         return err;
1238 }
1239 EXPORT_SYMBOL(p9_client_write);
1240
1241 struct p9_wstat *p9_client_stat(struct p9_fid *fid)
1242 {
1243         int err;
1244         struct p9_client *clnt;
1245         struct p9_wstat *ret = kmalloc(sizeof(struct p9_wstat), GFP_KERNEL);
1246         struct p9_req_t *req;
1247         u16 ignored;
1248
1249         P9_DPRINTK(P9_DEBUG_9P, ">>> TSTAT fid %d\n", fid->fid);
1250
1251         if (!ret)
1252                 return ERR_PTR(-ENOMEM);
1253
1254         err = 0;
1255         clnt = fid->clnt;
1256
1257         req = p9_client_rpc(clnt, P9_TSTAT, "d", fid->fid);
1258         if (IS_ERR(req)) {
1259                 err = PTR_ERR(req);
1260                 goto error;
1261         }
1262
1263         err = p9pdu_readf(req->rc, clnt->proto_version, "wS", &ignored, ret);
1264         if (err) {
1265                 p9pdu_dump(1, req->rc);
1266                 p9_free_req(clnt, req);
1267                 goto error;
1268         }
1269
1270         P9_DPRINTK(P9_DEBUG_9P,
1271                 "<<< RSTAT sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1272                 "<<<    mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1273                 "<<<    name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1274                 "<<<    uid=%d gid=%d n_muid=%d\n",
1275                 ret->size, ret->type, ret->dev, ret->qid.type,
1276                 (unsigned long long)ret->qid.path, ret->qid.version, ret->mode,
1277                 ret->atime, ret->mtime, (unsigned long long)ret->length,
1278                 ret->name, ret->uid, ret->gid, ret->muid, ret->extension,
1279                 ret->n_uid, ret->n_gid, ret->n_muid);
1280
1281         p9_free_req(clnt, req);
1282         return ret;
1283
1284 error:
1285         kfree(ret);
1286         return ERR_PTR(err);
1287 }
1288 EXPORT_SYMBOL(p9_client_stat);
1289
1290 static int p9_client_statsize(struct p9_wstat *wst, int proto_version)
1291 {
1292         int ret;
1293
1294         /* NOTE: size shouldn't include its own length */
1295         /* size[2] type[2] dev[4] qid[13] */
1296         /* mode[4] atime[4] mtime[4] length[8]*/
1297         /* name[s] uid[s] gid[s] muid[s] */
1298         ret = 2+4+13+4+4+4+8+2+2+2+2;
1299
1300         if (wst->name)
1301                 ret += strlen(wst->name);
1302         if (wst->uid)
1303                 ret += strlen(wst->uid);
1304         if (wst->gid)
1305                 ret += strlen(wst->gid);
1306         if (wst->muid)
1307                 ret += strlen(wst->muid);
1308
1309         if (proto_version == p9_proto_2000u) {
1310                 ret += 2+4+4+4; /* extension[s] n_uid[4] n_gid[4] n_muid[4] */
1311                 if (wst->extension)
1312                         ret += strlen(wst->extension);
1313         }
1314
1315         return ret;
1316 }
1317
1318 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst)
1319 {
1320         int err;
1321         struct p9_req_t *req;
1322         struct p9_client *clnt;
1323
1324         err = 0;
1325         clnt = fid->clnt;
1326         wst->size = p9_client_statsize(wst, clnt->proto_version);
1327         P9_DPRINTK(P9_DEBUG_9P, ">>> TWSTAT fid %d\n", fid->fid);
1328         P9_DPRINTK(P9_DEBUG_9P,
1329                 "     sz=%x type=%x dev=%x qid=%x.%llx.%x\n"
1330                 "     mode=%8.8x atime=%8.8x mtime=%8.8x length=%llx\n"
1331                 "     name=%s uid=%s gid=%s muid=%s extension=(%s)\n"
1332                 "     uid=%d gid=%d n_muid=%d\n",
1333                 wst->size, wst->type, wst->dev, wst->qid.type,
1334                 (unsigned long long)wst->qid.path, wst->qid.version, wst->mode,
1335                 wst->atime, wst->mtime, (unsigned long long)wst->length,
1336                 wst->name, wst->uid, wst->gid, wst->muid, wst->extension,
1337                 wst->n_uid, wst->n_gid, wst->n_muid);
1338
1339         req = p9_client_rpc(clnt, P9_TWSTAT, "dwS", fid->fid, wst->size+2, wst);
1340         if (IS_ERR(req)) {
1341                 err = PTR_ERR(req);
1342                 goto error;
1343         }
1344
1345         P9_DPRINTK(P9_DEBUG_9P, "<<< RWSTAT fid %d\n", fid->fid);
1346
1347         p9_free_req(clnt, req);
1348 error:
1349         return err;
1350 }
1351 EXPORT_SYMBOL(p9_client_wstat);