lib/libstand/nfs.c

   1 /* $FreeBSD: src/lib/libstand/nfs.c,v 1.2.6.3 2000/09/10 01:33:25 ps Exp $ */
   2 /*      $NetBSD: nfs.c,v 1.2 1998/01/24 12:43:09 drochner Exp $ */
   3
   4 /*-
   5  *  Copyright (c) 1993 John Brezak
   6  *  All rights reserved.
   7  *
   8  *  Redistribution and use in source and binary forms, with or without
   9  *  modification, are permitted provided that the following conditions
  10  *  are met:
  11  *  1. Redistributions of source code must retain the above copyright
  12  *     notice, this list of conditions and the following disclaimer.
  13  *  2. Redistributions in binary form must reproduce the above copyright
  14  *     notice, this list of conditions and the following disclaimer in the
  15  *     documentation and/or other materials provided with the distribution.
  16  *  3. The name of the author may not be used to endorse or promote products
  17  *     derived from this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
  20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  21  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  22  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  23  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  24  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  25  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  27  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  28  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #include <sys/param.h>
  33 #include <sys/time.h>
  34 #include <sys/socket.h>
  35 #include <sys/stat.h>
  36 #include <string.h>
  37 #include <stddef.h>
  38
  39 #include <netinet/in.h>
  40 #include <netinet/in_systm.h>
  41
  42 #include "rpcv2.h"
  43 #include "nfsv2.h"
  44
  45 #include "stand.h"
  46 #include "net.h"
  47 #include "netif.h"
  48 #include "rpc.h"
  49
  50 #define NFS_DEBUGxx
  51
  52 /* Define our own NFS attributes without NQNFS stuff. */
  53 struct nfsv2_fattrs {
  54         n_long  fa_type;
  55         n_long  fa_mode;
  56         n_long  fa_nlink;
  57         n_long  fa_uid;
  58         n_long  fa_gid;
  59         n_long  fa_size;
  60         n_long  fa_blocksize;
  61         n_long  fa_rdev;
  62         n_long  fa_blocks;
  63         n_long  fa_fsid;
  64         n_long  fa_fileid;
  65         struct nfsv2_time fa_atime;
  66         struct nfsv2_time fa_mtime;
  67         struct nfsv2_time fa_ctime;
  68 };
  69
  70
  71 struct nfs_read_args {
  72         u_char  fh[NFS_FHSIZE];
  73         n_long  off;
  74         n_long  len;
  75         n_long  xxx;                    /* XXX what's this for? */
  76 };
  77
  78 /*
  79  * Data part of nfs rpc reply (also the largest thing we receive).
  80  * Worry about the size of the structure declared on the stack.
  81  */
  82
  83 #define NFSREAD_MIN_SIZE 1024
  84 #define NFSREAD_MAX_SIZE 4096
  85
  86 struct nfs_read_repl {
  87         n_long  errno;
  88         struct  nfsv2_fattrs fa;
  89         n_long  count;
  90         u_char  data[NFSREAD_MAX_SIZE];
  91 };
  92
  93 #ifndef NFS_NOSYMLINK
  94 struct nfs_readlnk_repl {
  95         n_long  errno;
  96         n_long  len;
  97         char    path[NFS_MAXPATHLEN];
  98 };
  99 #endif
 100
 101 struct nfs_readdir_args {
 102         u_char  fh[NFS_FHSIZE];
 103         n_long  cookie;
 104         n_long  count;
 105 };
 106
 107 struct nfs_readdir_data {
 108         n_long  fileid;
 109         n_long  len;
 110         char    name[0];
 111 };
 112
 113 struct nfs_readdir_off {
 114         n_long  cookie;
 115         n_long  follows;
 116 };
 117
 118 struct nfs_iodesc {
 119         struct  iodesc  *iodesc;
 120         off_t   off;
 121         u_char  fh[NFS_FHSIZE];
 122         struct nfsv2_fattrs fa; /* all in network order */
 123 };
 124
 125 /*
 126  * XXX interactions with tftp? See nfswrapper.c for a confusing
 127  *     issue.
 128  */
 129 int             nfs_open(const char *path, struct open_file *f);
 130 static int      nfs_close(struct open_file *f);
 131 static int      nfs_read(struct open_file *f, void *buf, size_t size, size_t *resid);
 132 static int      nfs_write(struct open_file *f, void *buf, size_t size, size_t *resid);
 133 static off_t    nfs_seek(struct open_file *f, off_t offset, int where);
 134 static int      nfs_stat(struct open_file *f, struct stat *sb);
 135 static int      nfs_readdir(struct open_file *f, struct dirent *d);
 136
 137 struct  nfs_iodesc nfs_root_node;
 138
 139 struct fs_ops nfs_fsops = {
 140         "nfs",
 141         nfs_open,
 142         nfs_close,
 143         nfs_read,
 144         nfs_write,
 145         nfs_seek,
 146         nfs_stat,
 147         nfs_readdir
 148 };
 149
 150 static int nfs_read_size = NFSREAD_MIN_SIZE;
 151
 152 /*
 153  * Fetch the root file handle (call mount daemon)
 154  * Return zero or error number.
 155  */
 156 int
 157 nfs_getrootfh(struct iodesc *d, char *path, u_char *fhp)
 158 {
 159         int len;
 160         struct args {
 161                 n_long  len;
 162                 char    path[FNAME_SIZE];
 163         } *args;
 164         struct repl {
 165                 n_long  errno;
 166                 u_char  fh[NFS_FHSIZE];
 167         } *repl;
 168         struct {
 169                 n_long  h[RPC_HEADER_WORDS];
 170                 struct args d;
 171         } sdata;
 172         struct {
 173                 n_long  h[RPC_HEADER_WORDS];
 174                 struct repl d;
 175         } rdata;
 176         size_t cc;
 177
 178 #ifdef NFS_DEBUG
 179         if (debug)
 180                 printf("nfs_getrootfh: %s\n", path);
 181 #endif
 182
 183         args = &sdata.d;
 184         repl = &rdata.d;
 185
 186         bzero(args, sizeof(*args));
 187         len = strlen(path);
 188         if (len > sizeof(args->path))
 189                 len = sizeof(args->path);
 190         args->len = htonl(len);
 191         bcopy(path, args->path, len);
 192         len = 4 + roundup(len, 4);
 193
 194         cc = rpc_call(d, RPCPROG_MNT, RPCMNT_VER1, RPCMNT_MOUNT,
 195             args, len, repl, sizeof(*repl));
 196         if (cc == -1) {
 197                 /* errno was set by rpc_call */
 198                 return (errno);
 199         }
 200         if (cc < 4)
 201                 return (EBADRPC);
 202         if (repl->errno)
 203                 return (ntohl(repl->errno));
 204         bcopy(repl->fh, fhp, sizeof(repl->fh));
 205
 206         /*
 207          * Improve boot performance over NFS
 208          */
 209         if (getenv("nfs.read_size") != NULL)
 210                 nfs_read_size = strtol(getenv("nfs.read_size"), NULL, 0);
 211         if (nfs_read_size < NFSREAD_MIN_SIZE)
 212                 nfs_read_size = NFSREAD_MIN_SIZE;
 213         if (nfs_read_size > NFSREAD_MAX_SIZE)
 214                 nfs_read_size = NFSREAD_MAX_SIZE;
 215
 216         return (0);
 217 }
 218
 219 /*
 220  * Lookup a file.  Store handle and attributes.
 221  * Return zero or error number.
 222  */
 223 int
 224 nfs_lookupfh(struct nfs_iodesc *d, const char *name, struct nfs_iodesc *newfd)
 225 {
 226         int len, rlen;
 227         struct args {
 228                 u_char  fh[NFS_FHSIZE];
 229                 n_long  len;
 230                 char    name[FNAME_SIZE];
 231         } *args;
 232         struct repl {
 233                 n_long  errno;
 234                 u_char  fh[NFS_FHSIZE];
 235                 struct  nfsv2_fattrs fa;
 236         } *repl;
 237         struct {
 238                 n_long  h[RPC_HEADER_WORDS];
 239                 struct args d;
 240         } sdata;
 241         struct {
 242                 n_long  h[RPC_HEADER_WORDS];
 243                 struct repl d;
 244         } rdata;
 245         ssize_t cc;
 246
 247 #ifdef NFS_DEBUG
 248         if (debug)
 249                 printf("lookupfh: called\n");
 250 #endif
 251
 252         args = &sdata.d;
 253         repl = &rdata.d;
 254
 255         bzero(args, sizeof(*args));
 256         bcopy(d->fh, args->fh, sizeof(args->fh));
 257         len = strlen(name);
 258         if (len > sizeof(args->name))
 259                 len = sizeof(args->name);
 260         bcopy(name, args->name, len);
 261         args->len = htonl(len);
 262         len = 4 + roundup(len, 4);
 263         len += NFS_FHSIZE;
 264
 265         rlen = sizeof(*repl);
 266
 267         cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER2, NFSPROC_LOOKUP,
 268             args, len, repl, rlen);
 269         if (cc == -1)
 270                 return (errno);         /* XXX - from rpc_call */
 271         if (cc < 4)
 272                 return (EIO);
 273         if (repl->errno) {
 274                 /* saerrno.h now matches NFS error numbers. */
 275                 return (ntohl(repl->errno));
 276         }
 277         bcopy( repl->fh, &newfd->fh, sizeof(newfd->fh));
 278         bcopy(&repl->fa, &newfd->fa, sizeof(newfd->fa));
 279         return (0);
 280 }
 281
 282 #ifndef NFS_NOSYMLINK
 283 /*
 284  * Get the destination of a symbolic link.
 285  */
 286 int
 287 nfs_readlink(struct nfs_iodesc *d, char *buf)
 288 {
 289         struct {
 290                 n_long  h[RPC_HEADER_WORDS];
 291                 u_char fh[NFS_FHSIZE];
 292         } sdata;
 293         struct {
 294                 n_long  h[RPC_HEADER_WORDS];
 295                 struct nfs_readlnk_repl d;
 296         } rdata;
 297         ssize_t cc;
 298
 299 #ifdef NFS_DEBUG
 300         if (debug)
 301                 printf("readlink: called\n");
 302 #endif
 303
 304         bcopy(d->fh, sdata.fh, NFS_FHSIZE);
 305         cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER2, NFSPROC_READLINK,
 306                       sdata.fh, NFS_FHSIZE,
 307                       &rdata.d, sizeof(rdata.d));
 308         if (cc == -1)
 309                 return (errno);
 310
 311         if (cc < 4)
 312                 return (EIO);
 313
 314         if (rdata.d.errno)
 315                 return (ntohl(rdata.d.errno));
 316
 317         rdata.d.len = ntohl(rdata.d.len);
 318         if (rdata.d.len > NFS_MAXPATHLEN)
 319                 return (ENAMETOOLONG);
 320
 321         bcopy(rdata.d.path, buf, rdata.d.len);
 322         buf[rdata.d.len] = 0;
 323         return (0);
 324 }
 325 #endif
 326
 327 /*
 328  * Read data from a file.
 329  * Return transfer count or -1 (and set errno)
 330  */
 331 ssize_t
 332 nfs_readdata(struct nfs_iodesc *d, off_t off, void *addr, size_t len)
 333 {
 334         struct nfs_read_args *args;
 335         struct nfs_read_repl *repl;
 336         struct {
 337                 n_long  h[RPC_HEADER_WORDS];
 338                 struct nfs_read_args d;
 339         } sdata;
 340         struct {
 341                 n_long  h[RPC_HEADER_WORDS];
 342                 struct nfs_read_repl d;
 343         } rdata;
 344         size_t cc;
 345         long x;
 346         int hlen, rlen;
 347
 348         args = &sdata.d;
 349         repl = &rdata.d;
 350
 351         bcopy(d->fh, args->fh, NFS_FHSIZE);
 352         args->off = htonl((n_long)off);
 353         if (len > nfs_read_size)
 354                 len = nfs_read_size;
 355         args->len = htonl((n_long)len);
 356         args->xxx = htonl((n_long)0);
 357         hlen = offsetof(struct nfs_read_repl, data[0]);
 358
 359         cc = rpc_call(d->iodesc, NFS_PROG, NFS_VER2, NFSPROC_READ,
 360             args, sizeof(*args),
 361             repl, sizeof(*repl));
 362         if (cc == -1) {
 363                 /* errno was already set by rpc_call */
 364                 return (-1);
 365         }
 366         if (cc < hlen) {
 367                 errno = EBADRPC;
 368                 return (-1);
 369         }
 370         if (repl->errno) {
 371                 errno = ntohl(repl->errno);
 372                 return (-1);
 373         }
 374         rlen = cc - hlen;
 375         x = ntohl(repl->count);
 376         if (rlen < x) {
 377                 printf("nfsread: short packet, %d < %ld\n", rlen, x);
 378                 errno = EBADRPC;
 379                 return(-1);
 380         }
 381         bcopy(repl->data, addr, x);
 382         return (x);
 383 }
 384
 385 /*
 386  * Open a file.
 387  * return zero or error number
 388  */
 389 int
 390 nfs_open(const char *upath, struct open_file *f)
 391 {
 392         struct iodesc *desc;
 393         struct nfs_iodesc *currfd;
 394 #ifndef NFS_NOSYMLINK
 395         struct nfs_iodesc *newfd;
 396         struct nfsv2_fattrs *fa;
 397         char *cp, *ncp;
 398         int c;
 399         char namebuf[NFS_MAXPATHLEN + 1];
 400         char linkbuf[NFS_MAXPATHLEN + 1];
 401         int nlinks = 0;
 402 #endif
 403         int error;
 404         char *path;
 405
 406 #ifdef NFS_DEBUG
 407         if (debug)
 408             printf("nfs_open: %s (rootpath=%s)\n", path, rootpath);
 409 #endif
 410         if (!rootpath[0]) {
 411                 printf("no rootpath, no nfs\n");
 412                 return (ENXIO);
 413         }
 414
 415         /* Avoid trying out nfs_open for disk devices in the EFI loader */
 416 #ifndef __i386__
 417         if (strcmp(f->f_dev->dv_name, "net") != 0)
 418                 return (EINVAL);
 419 #endif
 420
 421         if (!(desc = socktodesc(*(int *)(f->f_devdata))))
 422                 return(EINVAL);
 423
 424         /* Bind to a reserved port. */
 425         desc->myport = htons(rpc_newport());
 426         desc->destip = rootip;
 427         if ((error = nfs_getrootfh(desc, rootpath, nfs_root_node.fh)))
 428                 return (error);
 429         nfs_root_node.iodesc = desc;
 430
 431 #ifndef NFS_NOSYMLINK
 432         /* Fake up attributes for the root dir. */
 433         fa = &nfs_root_node.fa;
 434         fa->fa_type  = htonl(NFDIR);
 435         fa->fa_mode  = htonl(0755);
 436         fa->fa_nlink = htonl(2);
 437
 438         currfd = &nfs_root_node;
 439         newfd = NULL;
 440
 441         cp = path = strdup(upath);
 442         if (path == NULL) {
 443             error = ENOMEM;
 444             goto out;
 445         }
 446         while (*cp) {
 447                 /*
 448                  * Remove extra separators
 449                  */
 450                 while (*cp == '/')
 451                         cp++;
 452
 453                 if (*cp == '\0')
 454                         break;
 455                 /*
 456                  * Check that current node is a directory.
 457                  */
 458                 if (currfd->fa.fa_type != htonl(NFDIR)) {
 459                         error = ENOTDIR;
 460                         goto out;
 461                 }
 462
 463                 /* allocate file system specific data structure */
 464                 newfd = malloc(sizeof(*newfd));
 465                 newfd->iodesc = currfd->iodesc;
 466                 newfd->off = 0;
 467
 468                 /*
 469                  * Get next component of path name.
 470                  */
 471                 {
 472                         int len = 0;
 473
 474                         ncp = cp;
 475                         while ((c = *cp) != '\0' && c != '/') {
 476                                 if (++len > NFS_MAXNAMLEN) {
 477                                         error = ENOENT;
 478                                         goto out;
 479                                 }
 480                                 cp++;
 481                         }
 482                         *cp = '\0';
 483                 }
 484
 485                 /* lookup a file handle */
 486                 error = nfs_lookupfh(currfd, ncp, newfd);
 487                 *cp = c;
 488                 if (error)
 489                         goto out;
 490
 491                 /*
 492                  * Check for symbolic link
 493                  */
 494                 if (newfd->fa.fa_type == htonl(NFLNK)) {
 495                         int link_len, len;
 496
 497                         error = nfs_readlink(newfd, linkbuf);
 498                         if (error)
 499                                 goto out;
 500
 501                         link_len = strlen(linkbuf);
 502                         len = strlen(cp);
 503
 504                         if (link_len + len > MAXPATHLEN
 505                             || ++nlinks > MAXSYMLINKS) {
 506                                 error = ENOENT;
 507                                 goto out;
 508                         }
 509
 510                         bcopy(cp, &namebuf[link_len], len + 1);
 511                         bcopy(linkbuf, namebuf, link_len);
 512
 513                         /*
 514                          * If absolute pathname, restart at root.
 515                          * If relative pathname, restart at parent directory.
 516                          */
 517                         cp = namebuf;
 518                         if (*cp == '/') {
 519                                 if (currfd != &nfs_root_node)
 520                                         free(currfd);
 521                                 currfd = &nfs_root_node;
 522                         }
 523
 524                         free(newfd);
 525                         newfd = NULL;
 526
 527                         continue;
 528                 }
 529
 530                 if (currfd != &nfs_root_node)
 531                         free(currfd);
 532                 currfd = newfd;
 533                 newfd = NULL;
 534         }
 535
 536         error = 0;
 537
 538 out:
 539         if (newfd)
 540                 free(newfd);
 541         if (path)
 542                 free(path);
 543 #else
 544         /* allocate file system specific data structure */
 545         currfd = malloc(sizeof(*currfd));
 546         currfd->iodesc = desc;
 547         currfd->off = 0;
 548
 549         error = nfs_lookupfh(&nfs_root_node, upath, currfd);
 550 #endif
 551         if (!error) {
 552                 f->f_fsdata = (void *)currfd;
 553                 return (0);
 554         }
 555
 556 #ifdef NFS_DEBUG
 557         if (debug)
 558                 printf("nfs_open: %s lookupfh failed: %s\n",
 559                     path, strerror(error));
 560 #endif
 561 #ifndef NFS_NOSYMLINK
 562         if (currfd != &nfs_root_node)
 563 #endif
 564                 free(currfd);
 565
 566         return (error);
 567 }
 568
 569 int
 570 nfs_close(struct open_file *f)
 571 {
 572         struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
 573
 574 #ifdef NFS_DEBUG
 575         if (debug)
 576                 printf("nfs_close: fp=0x%lx\n", (u_long)fp);
 577 #endif
 578
 579         f->f_fsdata = NULL;
 580         if (fp && fp != &nfs_root_node)
 581                 free(fp);
 582
 583         return (0);
 584 }
 585
 586 /*
 587  * read a portion of a file
 588  *
 589  * Parameters:
 590  *      resid:  out
 591  */
 592 int
 593 nfs_read(struct open_file *f, void *buf, size_t size, size_t *resid)
 594 {
 595         struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
 596         ssize_t cc;
 597         char *addr = buf;
 598
 599 #ifdef NFS_DEBUG
 600         if (debug)
 601                 printf("nfs_read: size=%lu off=%d\n", (u_long)size,
 602                        (int)fp->off);
 603 #endif
 604         while ((int)size > 0) {
 605                 twiddle();
 606                 cc = nfs_readdata(fp, fp->off, addr, size);
 607                 /* XXX maybe should retry on certain errors */
 608                 if (cc == -1) {
 609 #ifdef NFS_DEBUG
 610                         if (debug)
 611                                 printf("nfs_read: read: %s", strerror(errno));
 612 #endif
 613                         return (errno); /* XXX - from nfs_readdata */
 614                 }
 615                 if (cc == 0) {
 616 #ifdef NFS_DEBUG
 617                         if (debug)
 618                                 printf("nfs_read: hit EOF unexpectantly");
 619 #endif
 620                         goto ret;
 621                 }
 622                 fp->off += cc;
 623                 addr += cc;
 624                 size -= cc;
 625         }
 626 ret:
 627         if (resid)
 628                 *resid = size;
 629
 630         return (0);
 631 }
 632
 633 /*
 634  * Not implemented.
 635  *
 636  * Parameters:
 637  *      resid:  out
 638  */
 639 int
 640 nfs_write(struct open_file *f, void *buf, size_t size, size_t *resid)
 641 {
 642         return (EROFS);
 643 }
 644
 645 off_t
 646 nfs_seek(struct open_file *f, off_t offset, int where)
 647 {
 648         struct nfs_iodesc *d = (struct nfs_iodesc *)f->f_fsdata;
 649         n_long size = ntohl(d->fa.fa_size);
 650
 651         switch (where) {
 652         case SEEK_SET:
 653                 d->off = offset;
 654                 break;
 655         case SEEK_CUR:
 656                 d->off += offset;
 657                 break;
 658         case SEEK_END:
 659                 d->off = size - offset;
 660                 break;
 661         default:
 662                 return (-1);
 663         }
 664
 665         return (d->off);
 666 }
 667
 668 /* NFNON=0, NFREG=1, NFDIR=2, NFBLK=3, NFCHR=4, NFLNK=5 */
 669 int nfs_stat_types[8] = {
 670         0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 0 };
 671
 672 int
 673 nfs_stat(struct open_file *f, struct stat *sb)
 674 {
 675         struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
 676         n_long ftype, mode;
 677
 678         ftype = ntohl(fp->fa.fa_type);
 679         mode  = ntohl(fp->fa.fa_mode);
 680         mode |= nfs_stat_types[ftype & 7];
 681
 682         sb->st_mode  = mode;
 683         sb->st_nlink = ntohl(fp->fa.fa_nlink);
 684         sb->st_uid   = ntohl(fp->fa.fa_uid);
 685         sb->st_gid   = ntohl(fp->fa.fa_gid);
 686         sb->st_size  = ntohl(fp->fa.fa_size);
 687
 688         return (0);
 689 }
 690
 691 static int
 692 nfs_readdir(struct open_file *f, struct dirent *d)
 693 {
 694         struct nfs_iodesc *fp = (struct nfs_iodesc *)f->f_fsdata;
 695         struct nfs_readdir_args *args;
 696         struct nfs_readdir_data *rd;
 697         struct nfs_readdir_off  *roff = NULL;
 698         static char *buf;
 699         static n_long cookie = 0;
 700         size_t cc;
 701         n_long eof;
 702
 703         struct {
 704                 n_long h[RPC_HEADER_WORDS];
 705                 struct nfs_readdir_args d;
 706         } sdata;
 707         static struct {
 708                 n_long h[RPC_HEADER_WORDS];
 709                 u_char d[NFS_READDIRSIZE];
 710         } rdata;
 711
 712         if (cookie == 0) {
 713         refill:
 714                 args = &sdata.d;
 715                 bzero(args, sizeof(*args));
 716
 717                 bcopy(fp->fh, args->fh, NFS_FHSIZE);
 718                 args->cookie = htonl(cookie);
 719                 args->count  = htonl(NFS_READDIRSIZE);
 720
 721                 cc = rpc_call(fp->iodesc, NFS_PROG, NFS_VER2, NFSPROC_READDIR,
 722                               args, sizeof(*args),
 723                               rdata.d, sizeof(rdata.d));
 724                 buf  = rdata.d;
 725                 roff = (struct nfs_readdir_off *)buf;
 726                 if (ntohl(roff->cookie) != 0)
 727                         return 1;
 728         }
 729         roff = (struct nfs_readdir_off *)buf;
 730
 731         if (ntohl(roff->follows) == 0) {
 732                 eof = ntohl((roff+1)->cookie);
 733                 if (eof) {
 734                         cookie = 0;
 735                         return 1;
 736                 }
 737                 goto refill;
 738         }
 739
 740         buf += sizeof(struct nfs_readdir_off);
 741         rd = (struct nfs_readdir_data *)buf;
 742         d->d_namlen = ntohl(rd->len);
 743         bcopy(rd->name, d->d_name, d->d_namlen);
 744         d->d_name[d->d_namlen] = '\0';
 745
 746         buf += (sizeof(struct nfs_readdir_data) + roundup(htonl(rd->len),4));
 747         roff = (struct nfs_readdir_off *)buf;
 748         cookie = ntohl(roff->cookie);
 749         return 0;
 750 }