fs/nfs/nfs2xdr.c

   1 /*
   2  * linux/fs/nfs/nfs2xdr.c
   3  *
   4  * XDR functions to encode/decode NFS RPC arguments and results.
   5  *
   6  * Copyright (C) 1992, 1993, 1994  Rick Sladkey
   7  * Copyright (C) 1996 Olaf Kirch
   8  * 04 Aug 1998  Ion Badulescu <ionut@cs.columbia.edu>
   9  *              FIFO's need special handling in NFSv2
  10  */
  11
  12 #include <linux/param.h>
  13 #include <linux/time.h>
  14 #include <linux/mm.h>
  15 #include <linux/errno.h>
  16 #include <linux/string.h>
  17 #include <linux/in.h>
  18 #include <linux/pagemap.h>
  19 #include <linux/proc_fs.h>
  20 #include <linux/sunrpc/clnt.h>
  21 #include <linux/nfs.h>
  22 #include <linux/nfs2.h>
  23 #include <linux/nfs_fs.h>
  24 #include "internal.h"
  25
  26 #define NFSDBG_FACILITY         NFSDBG_XDR
  27
  28 /* Mapping from NFS error code to "errno" error code. */
  29 #define errno_NFSERR_IO         EIO
  30
  31 /*
  32  * Declare the space requirements for NFS arguments and replies as
  33  * number of 32bit-words
  34  */
  35 #define NFS_fhandle_sz          (8)
  36 #define NFS_sattr_sz            (8)
  37 #define NFS_filename_sz         (1+(NFS2_MAXNAMLEN>>2))
  38 #define NFS_path_sz             (1+(NFS2_MAXPATHLEN>>2))
  39 #define NFS_fattr_sz            (17)
  40 #define NFS_info_sz             (5)
  41 #define NFS_entry_sz            (NFS_filename_sz+3)
  42
  43 #define NFS_diropargs_sz        (NFS_fhandle_sz+NFS_filename_sz)
  44 #define NFS_removeargs_sz       (NFS_fhandle_sz+NFS_filename_sz)
  45 #define NFS_sattrargs_sz        (NFS_fhandle_sz+NFS_sattr_sz)
  46 #define NFS_readlinkargs_sz     (NFS_fhandle_sz)
  47 #define NFS_readargs_sz         (NFS_fhandle_sz+3)
  48 #define NFS_writeargs_sz        (NFS_fhandle_sz+4)
  49 #define NFS_createargs_sz       (NFS_diropargs_sz+NFS_sattr_sz)
  50 #define NFS_renameargs_sz       (NFS_diropargs_sz+NFS_diropargs_sz)
  51 #define NFS_linkargs_sz         (NFS_fhandle_sz+NFS_diropargs_sz)
  52 #define NFS_symlinkargs_sz      (NFS_diropargs_sz+1+NFS_sattr_sz)
  53 #define NFS_readdirargs_sz      (NFS_fhandle_sz+2)
  54
  55 #define NFS_attrstat_sz         (1+NFS_fattr_sz)
  56 #define NFS_diropres_sz         (1+NFS_fhandle_sz+NFS_fattr_sz)
  57 #define NFS_readlinkres_sz      (2)
  58 #define NFS_readres_sz          (1+NFS_fattr_sz+1)
  59 #define NFS_writeres_sz         (NFS_attrstat_sz)
  60 #define NFS_stat_sz             (1)
  61 #define NFS_readdirres_sz       (1)
  62 #define NFS_statfsres_sz        (1+NFS_info_sz)
  63
  64 /*
  65  * Common NFS XDR functions as inlines
  66  */
  67 static inline __be32 *
  68 xdr_encode_fhandle(__be32 *p, const struct nfs_fh *fhandle)
  69 {
  70         memcpy(p, fhandle->data, NFS2_FHSIZE);
  71         return p + XDR_QUADLEN(NFS2_FHSIZE);
  72 }
  73
  74 static inline __be32 *
  75 xdr_decode_fhandle(__be32 *p, struct nfs_fh *fhandle)
  76 {
  77         /* NFSv2 handles have a fixed length */
  78         fhandle->size = NFS2_FHSIZE;
  79         memcpy(fhandle->data, p, NFS2_FHSIZE);
  80         return p + XDR_QUADLEN(NFS2_FHSIZE);
  81 }
  82
  83 static inline __be32*
  84 xdr_encode_time(__be32 *p, struct timespec *timep)
  85 {
  86         *p++ = htonl(timep->tv_sec);
  87         /* Convert nanoseconds into microseconds */
  88         *p++ = htonl(timep->tv_nsec ? timep->tv_nsec / 1000 : 0);
  89         return p;
  90 }
  91
  92 static inline __be32*
  93 xdr_encode_current_server_time(__be32 *p, struct timespec *timep)
  94 {
  95         /*
  96          * Passing the invalid value useconds=1000000 is a
  97          * Sun convention for "set to current server time".
  98          * It's needed to make permissions checks for the
  99          * "touch" program across v2 mounts to Solaris and
 100          * Irix boxes work correctly. See description of
 101          * sattr in section 6.1 of "NFS Illustrated" by
 102          * Brent Callaghan, Addison-Wesley, ISBN 0-201-32750-5
 103          */
 104         *p++ = htonl(timep->tv_sec);
 105         *p++ = htonl(1000000);
 106         return p;
 107 }
 108
 109 static inline __be32*
 110 xdr_decode_time(__be32 *p, struct timespec *timep)
 111 {
 112         timep->tv_sec = ntohl(*p++);
 113         /* Convert microseconds into nanoseconds */
 114         timep->tv_nsec = ntohl(*p++) * 1000;
 115         return p;
 116 }
 117
 118 static __be32 *
 119 xdr_decode_fattr(__be32 *p, struct nfs_fattr *fattr)
 120 {
 121         u32 rdev, type;
 122         type = ntohl(*p++);
 123         fattr->mode = ntohl(*p++);
 124         fattr->nlink = ntohl(*p++);
 125         fattr->uid = ntohl(*p++);
 126         fattr->gid = ntohl(*p++);
 127         fattr->size = ntohl(*p++);
 128         fattr->du.nfs2.blocksize = ntohl(*p++);
 129         rdev = ntohl(*p++);
 130         fattr->du.nfs2.blocks = ntohl(*p++);
 131         fattr->fsid.major = ntohl(*p++);
 132         fattr->fsid.minor = 0;
 133         fattr->fileid = ntohl(*p++);
 134         p = xdr_decode_time(p, &fattr->atime);
 135         p = xdr_decode_time(p, &fattr->mtime);
 136         p = xdr_decode_time(p, &fattr->ctime);
 137         fattr->valid |= NFS_ATTR_FATTR_V2;
 138         fattr->rdev = new_decode_dev(rdev);
 139         if (type == NFCHR && rdev == NFS2_FIFO_DEV) {
 140                 fattr->mode = (fattr->mode & ~S_IFMT) | S_IFIFO;
 141                 fattr->rdev = 0;
 142         }
 143         return p;
 144 }
 145
 146 static inline __be32 *
 147 xdr_encode_sattr(__be32 *p, struct iattr *attr)
 148 {
 149         const __be32 not_set = __constant_htonl(0xFFFFFFFF);
 150
 151         *p++ = (attr->ia_valid & ATTR_MODE) ? htonl(attr->ia_mode) : not_set;
 152         *p++ = (attr->ia_valid & ATTR_UID) ? htonl(attr->ia_uid) : not_set;
 153         *p++ = (attr->ia_valid & ATTR_GID) ? htonl(attr->ia_gid) : not_set;
 154         *p++ = (attr->ia_valid & ATTR_SIZE) ? htonl(attr->ia_size) : not_set;
 155
 156         if (attr->ia_valid & ATTR_ATIME_SET) {
 157                 p = xdr_encode_time(p, &attr->ia_atime);
 158         } else if (attr->ia_valid & ATTR_ATIME) {
 159                 p = xdr_encode_current_server_time(p, &attr->ia_atime);
 160         } else {
 161                 *p++ = not_set;
 162                 *p++ = not_set;
 163         }
 164
 165         if (attr->ia_valid & ATTR_MTIME_SET) {
 166                 p = xdr_encode_time(p, &attr->ia_mtime);
 167         } else if (attr->ia_valid & ATTR_MTIME) {
 168                 p = xdr_encode_current_server_time(p, &attr->ia_mtime);
 169         } else {
 170                 *p++ = not_set;
 171                 *p++ = not_set;
 172         }
 173         return p;
 174 }
 175
 176 /*
 177  * NFS encode functions
 178  */
 179 /*
 180  * Encode file handle argument
 181  * GETATTR, READLINK, STATFS
 182  */
 183 static int
 184 nfs_xdr_fhandle(struct rpc_rqst *req, __be32 *p, struct nfs_fh *fh)
 185 {
 186         p = xdr_encode_fhandle(p, fh);
 187         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 188         return 0;
 189 }
 190
 191 /*
 192  * Encode SETATTR arguments
 193  */
 194 static int
 195 nfs_xdr_sattrargs(struct rpc_rqst *req, __be32 *p, struct nfs_sattrargs *args)
 196 {
 197         p = xdr_encode_fhandle(p, args->fh);
 198         p = xdr_encode_sattr(p, args->sattr);
 199         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 200         return 0;
 201 }
 202
 203 /*
 204  * Encode directory ops argument
 205  * LOOKUP, RMDIR
 206  */
 207 static int
 208 nfs_xdr_diropargs(struct rpc_rqst *req, __be32 *p, struct nfs_diropargs *args)
 209 {
 210         p = xdr_encode_fhandle(p, args->fh);
 211         p = xdr_encode_array(p, args->name, args->len);
 212         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 213         return 0;
 214 }
 215
 216 /*
 217  * Encode REMOVE argument
 218  */
 219 static int
 220 nfs_xdr_removeargs(struct rpc_rqst *req, __be32 *p, const struct nfs_removeargs *args)
 221 {
 222         p = xdr_encode_fhandle(p, args->fh);
 223         p = xdr_encode_array(p, args->name.name, args->name.len);
 224         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 225         return 0;
 226 }
 227
 228 /*
 229  * Arguments to a READ call. Since we read data directly into the page
 230  * cache, we also set up the reply iovec here so that iov[1] points
 231  * exactly to the page we want to fetch.
 232  */
 233 static int
 234 nfs_xdr_readargs(struct rpc_rqst *req, __be32 *p, struct nfs_readargs *args)
 235 {
 236         struct rpc_auth *auth = req->rq_cred->cr_auth;
 237         unsigned int replen;
 238         u32 offset = (u32)args->offset;
 239         u32 count = args->count;
 240
 241         p = xdr_encode_fhandle(p, args->fh);
 242         *p++ = htonl(offset);
 243         *p++ = htonl(count);
 244         *p++ = htonl(count);
 245         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 246
 247         /* Inline the page array */
 248         replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS_readres_sz) << 2;
 249         xdr_inline_pages(&req->rq_rcv_buf, replen,
 250                          args->pages, args->pgbase, count);
 251         req->rq_rcv_buf.flags |= XDRBUF_READ;
 252         return 0;
 253 }
 254
 255 /*
 256  * Decode READ reply
 257  */
 258 static int
 259 nfs_xdr_readres(struct rpc_rqst *req, __be32 *p, struct nfs_readres *res)
 260 {
 261         struct kvec *iov = req->rq_rcv_buf.head;
 262         size_t hdrlen;
 263         u32 count, recvd;
 264         int status;
 265
 266         if ((status = ntohl(*p++)))
 267                 return nfs_stat_to_errno(status);
 268         p = xdr_decode_fattr(p, res->fattr);
 269
 270         count = ntohl(*p++);
 271         res->eof = 0;
 272         hdrlen = (u8 *) p - (u8 *) iov->iov_base;
 273         if (iov->iov_len < hdrlen) {
 274                 dprintk("NFS: READ reply header overflowed:"
 275                                 "length %Zu > %Zu\n", hdrlen, iov->iov_len);
 276                 return -errno_NFSERR_IO;
 277         } else if (iov->iov_len != hdrlen) {
 278                 dprintk("NFS: READ header is short. iovec will be shifted.\n");
 279                 xdr_shift_buf(&req->rq_rcv_buf, iov->iov_len - hdrlen);
 280         }
 281
 282         recvd = req->rq_rcv_buf.len - hdrlen;
 283         if (count > recvd) {
 284                 dprintk("NFS: server cheating in read reply: "
 285                         "count %u > recvd %u\n", count, recvd);
 286                 count = recvd;
 287         }
 288
 289         dprintk("RPC:      readres OK count %u\n", count);
 290         if (count < res->count)
 291                 res->count = count;
 292
 293         return count;
 294 }
 295
 296
 297 /*
 298  * Write arguments. Splice the buffer to be written into the iovec.
 299  */
 300 static int
 301 nfs_xdr_writeargs(struct rpc_rqst *req, __be32 *p, struct nfs_writeargs *args)
 302 {
 303         struct xdr_buf *sndbuf = &req->rq_snd_buf;
 304         u32 offset = (u32)args->offset;
 305         u32 count = args->count;
 306
 307         p = xdr_encode_fhandle(p, args->fh);
 308         *p++ = htonl(offset);
 309         *p++ = htonl(offset);
 310         *p++ = htonl(count);
 311         *p++ = htonl(count);
 312         sndbuf->len = xdr_adjust_iovec(sndbuf->head, p);
 313
 314         /* Copy the page array */
 315         xdr_encode_pages(sndbuf, args->pages, args->pgbase, count);
 316         sndbuf->flags |= XDRBUF_WRITE;
 317         return 0;
 318 }
 319
 320 /*
 321  * Encode create arguments
 322  * CREATE, MKDIR
 323  */
 324 static int
 325 nfs_xdr_createargs(struct rpc_rqst *req, __be32 *p, struct nfs_createargs *args)
 326 {
 327         p = xdr_encode_fhandle(p, args->fh);
 328         p = xdr_encode_array(p, args->name, args->len);
 329         p = xdr_encode_sattr(p, args->sattr);
 330         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 331         return 0;
 332 }
 333
 334 /*
 335  * Encode RENAME arguments
 336  */
 337 static int
 338 nfs_xdr_renameargs(struct rpc_rqst *req, __be32 *p, struct nfs_renameargs *args)
 339 {
 340         p = xdr_encode_fhandle(p, args->old_dir);
 341         p = xdr_encode_array(p, args->old_name->name, args->old_name->len);
 342         p = xdr_encode_fhandle(p, args->new_dir);
 343         p = xdr_encode_array(p, args->new_name->name, args->new_name->len);
 344         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 345         return 0;
 346 }
 347
 348 /*
 349  * Encode LINK arguments
 350  */
 351 static int
 352 nfs_xdr_linkargs(struct rpc_rqst *req, __be32 *p, struct nfs_linkargs *args)
 353 {
 354         p = xdr_encode_fhandle(p, args->fromfh);
 355         p = xdr_encode_fhandle(p, args->tofh);
 356         p = xdr_encode_array(p, args->toname, args->tolen);
 357         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 358         return 0;
 359 }
 360
 361 /*
 362  * Encode SYMLINK arguments
 363  */
 364 static int
 365 nfs_xdr_symlinkargs(struct rpc_rqst *req, __be32 *p, struct nfs_symlinkargs *args)
 366 {
 367         struct xdr_buf *sndbuf = &req->rq_snd_buf;
 368         size_t pad;
 369
 370         p = xdr_encode_fhandle(p, args->fromfh);
 371         p = xdr_encode_array(p, args->fromname, args->fromlen);
 372         *p++ = htonl(args->pathlen);
 373         sndbuf->len = xdr_adjust_iovec(sndbuf->head, p);
 374
 375         xdr_encode_pages(sndbuf, args->pages, 0, args->pathlen);
 376
 377         /*
 378          * xdr_encode_pages may have added a few bytes to ensure the
 379          * pathname ends on a 4-byte boundary.  Start encoding the
 380          * attributes after the pad bytes.
 381          */
 382         pad = sndbuf->tail->iov_len;
 383         if (pad > 0)
 384                 p++;
 385         p = xdr_encode_sattr(p, args->sattr);
 386         sndbuf->len += xdr_adjust_iovec(sndbuf->tail, p) - pad;
 387         return 0;
 388 }
 389
 390 /*
 391  * Encode arguments to readdir call
 392  */
 393 static int
 394 nfs_xdr_readdirargs(struct rpc_rqst *req, __be32 *p, struct nfs_readdirargs *args)
 395 {
 396         struct rpc_auth *auth = req->rq_cred->cr_auth;
 397         unsigned int replen;
 398         u32 count = args->count;
 399
 400         p = xdr_encode_fhandle(p, args->fh);
 401         *p++ = htonl(args->cookie);
 402         *p++ = htonl(count); /* see above */
 403         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 404
 405         /* Inline the page array */
 406         replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS_readdirres_sz) << 2;
 407         xdr_inline_pages(&req->rq_rcv_buf, replen, args->pages, 0, count);
 408         return 0;
 409 }
 410
 411 /*
 412  * Decode the result of a readdir call.
 413  * We're not really decoding anymore, we just leave the buffer untouched
 414  * and only check that it is syntactically correct.
 415  * The real decoding happens in nfs_decode_entry below, called directly
 416  * from nfs_readdir for each entry.
 417  */
 418 static int
 419 nfs_xdr_readdirres(struct rpc_rqst *req, __be32 *p, void *dummy)
 420 {
 421         struct xdr_buf *rcvbuf = &req->rq_rcv_buf;
 422         struct kvec *iov = rcvbuf->head;
 423         struct page **page;
 424         size_t hdrlen;
 425         unsigned int pglen, recvd;
 426         int status, nr = 0;
 427
 428         if ((status = ntohl(*p++)))
 429                 return nfs_stat_to_errno(status);
 430
 431         hdrlen = (u8 *) p - (u8 *) iov->iov_base;
 432         if (iov->iov_len < hdrlen) {
 433                 dprintk("NFS: READDIR reply header overflowed:"
 434                                 "length %Zu > %Zu\n", hdrlen, iov->iov_len);
 435                 return -errno_NFSERR_IO;
 436         } else if (iov->iov_len != hdrlen) {
 437                 dprintk("NFS: READDIR header is short. iovec will be shifted.\n");
 438                 xdr_shift_buf(rcvbuf, iov->iov_len - hdrlen);
 439         }
 440
 441         pglen = rcvbuf->page_len;
 442         recvd = rcvbuf->len - hdrlen;
 443         if (pglen > recvd)
 444                 pglen = recvd;
 445         page = rcvbuf->pages;
 446         return nr;
 447 }
 448
 449 static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
 450 {
 451         dprintk("nfs: %s: prematurely hit end of receive buffer. "
 452                 "Remaining buffer length is %tu words.\n",
 453                 func, xdr->end - xdr->p);
 454 }
 455
 456 __be32 *
 457 nfs_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry, struct nfs_server *server, int plus)
 458 {
 459         __be32 *p;
 460         p = xdr_inline_decode(xdr, 4);
 461         if (unlikely(!p))
 462                 goto out_overflow;
 463         if (!ntohl(*p++)) {
 464                 p = xdr_inline_decode(xdr, 4);
 465                 if (unlikely(!p))
 466                         goto out_overflow;
 467                 if (!ntohl(*p++))
 468                         return ERR_PTR(-EAGAIN);
 469                 entry->eof = 1;
 470                 return ERR_PTR(-EBADCOOKIE);
 471         }
 472
 473         p = xdr_inline_decode(xdr, 8);
 474         if (unlikely(!p))
 475                 goto out_overflow;
 476
 477         entry->ino        = ntohl(*p++);
 478         entry->len        = ntohl(*p++);
 479
 480         p = xdr_inline_decode(xdr, entry->len + 4);
 481         if (unlikely(!p))
 482                 goto out_overflow;
 483         entry->name       = (const char *) p;
 484         p                += XDR_QUADLEN(entry->len);
 485         entry->prev_cookie        = entry->cookie;
 486         entry->cookie     = ntohl(*p++);
 487
 488         p = xdr_inline_peek(xdr, 8);
 489         if (p != NULL)
 490                 entry->eof = !p[0] && p[1];
 491         else
 492                 entry->eof = 0;
 493
 494         return p;
 495
 496 out_overflow:
 497         print_overflow_msg(__func__, xdr);
 498         return ERR_PTR(-EIO);
 499 }
 500
 501 /*
 502  * NFS XDR decode functions
 503  */
 504 /*
 505  * Decode simple status reply
 506  */
 507 static int
 508 nfs_xdr_stat(struct rpc_rqst *req, __be32 *p, void *dummy)
 509 {
 510         int     status;
 511
 512         if ((status = ntohl(*p++)) != 0)
 513                 status = nfs_stat_to_errno(status);
 514         return status;
 515 }
 516
 517 /*
 518  * Decode attrstat reply
 519  * GETATTR, SETATTR, WRITE
 520  */
 521 static int
 522 nfs_xdr_attrstat(struct rpc_rqst *req, __be32 *p, struct nfs_fattr *fattr)
 523 {
 524         int     status;
 525
 526         if ((status = ntohl(*p++)))
 527                 return nfs_stat_to_errno(status);
 528         xdr_decode_fattr(p, fattr);
 529         return 0;
 530 }
 531
 532 /*
 533  * Decode diropres reply
 534  * LOOKUP, CREATE, MKDIR
 535  */
 536 static int
 537 nfs_xdr_diropres(struct rpc_rqst *req, __be32 *p, struct nfs_diropok *res)
 538 {
 539         int     status;
 540
 541         if ((status = ntohl(*p++)))
 542                 return nfs_stat_to_errno(status);
 543         p = xdr_decode_fhandle(p, res->fh);
 544         xdr_decode_fattr(p, res->fattr);
 545         return 0;
 546 }
 547
 548 /*
 549  * Encode READLINK args
 550  */
 551 static int
 552 nfs_xdr_readlinkargs(struct rpc_rqst *req, __be32 *p, struct nfs_readlinkargs *args)
 553 {
 554         struct rpc_auth *auth = req->rq_cred->cr_auth;
 555         unsigned int replen;
 556
 557         p = xdr_encode_fhandle(p, args->fh);
 558         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 559
 560         /* Inline the page array */
 561         replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS_readlinkres_sz) << 2;
 562         xdr_inline_pages(&req->rq_rcv_buf, replen, args->pages, args->pgbase, args->pglen);
 563         return 0;
 564 }
 565
 566 /*
 567  * Decode READLINK reply
 568  */
 569 static int
 570 nfs_xdr_readlinkres(struct rpc_rqst *req, __be32 *p, void *dummy)
 571 {
 572         struct xdr_buf *rcvbuf = &req->rq_rcv_buf;
 573         struct kvec *iov = rcvbuf->head;
 574         size_t hdrlen;
 575         u32 len, recvd;
 576         int     status;
 577
 578         if ((status = ntohl(*p++)))
 579                 return nfs_stat_to_errno(status);
 580         /* Convert length of symlink */
 581         len = ntohl(*p++);
 582         if (len >= rcvbuf->page_len) {
 583                 dprintk("nfs: server returned giant symlink!\n");
 584                 return -ENAMETOOLONG;
 585         }
 586         hdrlen = (u8 *) p - (u8 *) iov->iov_base;
 587         if (iov->iov_len < hdrlen) {
 588                 dprintk("NFS: READLINK reply header overflowed:"
 589                                 "length %Zu > %Zu\n", hdrlen, iov->iov_len);
 590                 return -errno_NFSERR_IO;
 591         } else if (iov->iov_len != hdrlen) {
 592                 dprintk("NFS: READLINK header is short. iovec will be shifted.\n");
 593                 xdr_shift_buf(rcvbuf, iov->iov_len - hdrlen);
 594         }
 595         recvd = req->rq_rcv_buf.len - hdrlen;
 596         if (recvd < len) {
 597                 dprintk("NFS: server cheating in readlink reply: "
 598                                 "count %u > recvd %u\n", len, recvd);
 599                 return -EIO;
 600         }
 601
 602         xdr_terminate_string(rcvbuf, len);
 603         return 0;
 604 }
 605
 606 /*
 607  * Decode WRITE reply
 608  */
 609 static int
 610 nfs_xdr_writeres(struct rpc_rqst *req, __be32 *p, struct nfs_writeres *res)
 611 {
 612         res->verf->committed = NFS_FILE_SYNC;
 613         return nfs_xdr_attrstat(req, p, res->fattr);
 614 }
 615
 616 /*
 617  * Decode STATFS reply
 618  */
 619 static int
 620 nfs_xdr_statfsres(struct rpc_rqst *req, __be32 *p, struct nfs2_fsstat *res)
 621 {
 622         int     status;
 623
 624         if ((status = ntohl(*p++)))
 625                 return nfs_stat_to_errno(status);
 626
 627         res->tsize  = ntohl(*p++);
 628         res->bsize  = ntohl(*p++);
 629         res->blocks = ntohl(*p++);
 630         res->bfree  = ntohl(*p++);
 631         res->bavail = ntohl(*p++);
 632         return 0;
 633 }
 634
 635 /*
 636  * We need to translate between nfs status return values and
 637  * the local errno values which may not be the same.
 638  */
 639 static struct {
 640         int stat;
 641         int errno;
 642 } nfs_errtbl[] = {
 643         { NFS_OK,               0               },
 644         { NFSERR_PERM,          -EPERM          },
 645         { NFSERR_NOENT,         -ENOENT         },
 646         { NFSERR_IO,            -errno_NFSERR_IO},
 647         { NFSERR_NXIO,          -ENXIO          },
 648 /*      { NFSERR_EAGAIN,        -EAGAIN         }, */
 649         { NFSERR_ACCES,         -EACCES         },
 650         { NFSERR_EXIST,         -EEXIST         },
 651         { NFSERR_XDEV,          -EXDEV          },
 652         { NFSERR_NODEV,         -ENODEV         },
 653         { NFSERR_NOTDIR,        -ENOTDIR        },
 654         { NFSERR_ISDIR,         -EISDIR         },
 655         { NFSERR_INVAL,         -EINVAL         },
 656         { NFSERR_FBIG,          -EFBIG          },
 657         { NFSERR_NOSPC,         -ENOSPC         },
 658         { NFSERR_ROFS,          -EROFS          },
 659         { NFSERR_MLINK,         -EMLINK         },
 660         { NFSERR_NAMETOOLONG,   -ENAMETOOLONG   },
 661         { NFSERR_NOTEMPTY,      -ENOTEMPTY      },
 662         { NFSERR_DQUOT,         -EDQUOT         },
 663         { NFSERR_STALE,         -ESTALE         },
 664         { NFSERR_REMOTE,        -EREMOTE        },
 665 #ifdef EWFLUSH
 666         { NFSERR_WFLUSH,        -EWFLUSH        },
 667 #endif
 668         { NFSERR_BADHANDLE,     -EBADHANDLE     },
 669         { NFSERR_NOT_SYNC,      -ENOTSYNC       },
 670         { NFSERR_BAD_COOKIE,    -EBADCOOKIE     },
 671         { NFSERR_NOTSUPP,       -ENOTSUPP       },
 672         { NFSERR_TOOSMALL,      -ETOOSMALL      },
 673         { NFSERR_SERVERFAULT,   -EREMOTEIO      },
 674         { NFSERR_BADTYPE,       -EBADTYPE       },
 675         { NFSERR_JUKEBOX,       -EJUKEBOX       },
 676         { -1,                   -EIO            }
 677 };
 678
 679 /*
 680  * Convert an NFS error code to a local one.
 681  * This one is used jointly by NFSv2 and NFSv3.
 682  */
 683 int
 684 nfs_stat_to_errno(int stat)
 685 {
 686         int i;
 687
 688         for (i = 0; nfs_errtbl[i].stat != -1; i++) {
 689                 if (nfs_errtbl[i].stat == stat)
 690                         return nfs_errtbl[i].errno;
 691         }
 692         dprintk("nfs_stat_to_errno: bad nfs status return value: %d\n", stat);
 693         return nfs_errtbl[i].errno;
 694 }
 695
 696 #define PROC(proc, argtype, restype, timer)                             \
 697 [NFSPROC_##proc] = {                                                    \
 698         .p_proc     =  NFSPROC_##proc,                                  \
 699         .p_encode   =  (kxdrproc_t) nfs_xdr_##argtype,                  \
 700         .p_decode   =  (kxdrproc_t) nfs_xdr_##restype,                  \
 701         .p_arglen   =  NFS_##argtype##_sz,                              \
 702         .p_replen   =  NFS_##restype##_sz,                              \
 703         .p_timer    =  timer,                                           \
 704         .p_statidx  =  NFSPROC_##proc,                                  \
 705         .p_name     =  #proc,                                           \
 706         }
 707 struct rpc_procinfo     nfs_procedures[] = {
 708     PROC(GETATTR,       fhandle,        attrstat, 1),
 709     PROC(SETATTR,       sattrargs,      attrstat, 0),
 710     PROC(LOOKUP,        diropargs,      diropres, 2),
 711     PROC(READLINK,      readlinkargs,   readlinkres, 3),
 712     PROC(READ,          readargs,       readres, 3),
 713     PROC(WRITE,         writeargs,      writeres, 4),
 714     PROC(CREATE,        createargs,     diropres, 0),
 715     PROC(REMOVE,        removeargs,     stat, 0),
 716     PROC(RENAME,        renameargs,     stat, 0),
 717     PROC(LINK,          linkargs,       stat, 0),
 718     PROC(SYMLINK,       symlinkargs,    stat, 0),
 719     PROC(MKDIR,         createargs,     diropres, 0),
 720     PROC(RMDIR,         diropargs,      stat, 0),
 721     PROC(READDIR,       readdirargs,    readdirres, 3),
 722     PROC(STATFS,        fhandle,        statfsres, 0),
 723 };
 724
 725 struct rpc_version              nfs_version2 = {
 726         .number                 = 2,
 727         .nrprocs                = ARRAY_SIZE(nfs_procedures),
 728         .procs                  = nfs_procedures
 729 };