fs/nfsd/nfs3xdr.c

   1 /*
   2  * linux/fs/nfsd/nfs3xdr.c
   3  *
   4  * XDR support for nfsd/protocol version 3.
   5  *
   6  * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
   7  *
   8  * 2003-08-09 Jamie Lokier: Use htonl() for nanoseconds, not htons()!
   9  */
  10
  11 #include <linux/types.h>
  12 #include <linux/time.h>
  13 #include <linux/nfs3.h>
  14 #include <linux/list.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/dcache.h>
  17 #include <linux/namei.h>
  18 #include <linux/mm.h>
  19 #include <linux/vfs.h>
  20 #include <linux/sunrpc/xdr.h>
  21 #include <linux/sunrpc/svc.h>
  22 #include <linux/nfsd/nfsd.h>
  23 #include <linux/nfsd/xdr3.h>
  24
  25 #define NFSDDBG_FACILITY                NFSDDBG_XDR
  26
  27
  28 /*
  29  * Mapping of S_IF* types to NFS file types
  30  */
  31 static u32      nfs3_ftypes[] = {
  32         NF3NON,  NF3FIFO, NF3CHR, NF3BAD,
  33         NF3DIR,  NF3BAD,  NF3BLK, NF3BAD,
  34         NF3REG,  NF3BAD,  NF3LNK, NF3BAD,
  35         NF3SOCK, NF3BAD,  NF3LNK, NF3BAD,
  36 };
  37
  38 /*
  39  * XDR functions for basic NFS types
  40  */
  41 static __be32 *
  42 encode_time3(__be32 *p, struct timespec *time)
  43 {
  44         *p++ = htonl((u32) time->tv_sec); *p++ = htonl(time->tv_nsec);
  45         return p;
  46 }
  47
  48 static __be32 *
  49 decode_time3(__be32 *p, struct timespec *time)
  50 {
  51         time->tv_sec = ntohl(*p++);
  52         time->tv_nsec = ntohl(*p++);
  53         return p;
  54 }
  55
  56 static __be32 *
  57 decode_fh(__be32 *p, struct svc_fh *fhp)
  58 {
  59         unsigned int size;
  60         fh_init(fhp, NFS3_FHSIZE);
  61         size = ntohl(*p++);
  62         if (size > NFS3_FHSIZE)
  63                 return NULL;
  64
  65         memcpy(&fhp->fh_handle.fh_base, p, size);
  66         fhp->fh_handle.fh_size = size;
  67         return p + XDR_QUADLEN(size);
  68 }
  69
  70 /* Helper function for NFSv3 ACL code */
  71 __be32 *nfs3svc_decode_fh(__be32 *p, struct svc_fh *fhp)
  72 {
  73         return decode_fh(p, fhp);
  74 }
  75
  76 static __be32 *
  77 encode_fh(__be32 *p, struct svc_fh *fhp)
  78 {
  79         unsigned int size = fhp->fh_handle.fh_size;
  80         *p++ = htonl(size);
  81         if (size) p[XDR_QUADLEN(size)-1]=0;
  82         memcpy(p, &fhp->fh_handle.fh_base, size);
  83         return p + XDR_QUADLEN(size);
  84 }
  85
  86 /*
  87  * Decode a file name and make sure that the path contains
  88  * no slashes or null bytes.
  89  */
  90 static __be32 *
  91 decode_filename(__be32 *p, char **namp, int *lenp)
  92 {
  93         char            *name;
  94         int             i;
  95
  96         if ((p = xdr_decode_string_inplace(p, namp, lenp, NFS3_MAXNAMLEN)) != NULL) {
  97                 for (i = 0, name = *namp; i < *lenp; i++, name++) {
  98                         if (*name == '\0' || *name == '/')
  99                                 return NULL;
 100                 }
 101         }
 102
 103         return p;
 104 }
 105
 106 static __be32 *
 107 decode_sattr3(__be32 *p, struct iattr *iap)
 108 {
 109         u32     tmp;
 110
 111         iap->ia_valid = 0;
 112
 113         if (*p++) {
 114                 iap->ia_valid |= ATTR_MODE;
 115                 iap->ia_mode = ntohl(*p++);
 116         }
 117         if (*p++) {
 118                 iap->ia_valid |= ATTR_UID;
 119                 iap->ia_uid = ntohl(*p++);
 120         }
 121         if (*p++) {
 122                 iap->ia_valid |= ATTR_GID;
 123                 iap->ia_gid = ntohl(*p++);
 124         }
 125         if (*p++) {
 126                 u64     newsize;
 127
 128                 iap->ia_valid |= ATTR_SIZE;
 129                 p = xdr_decode_hyper(p, &newsize);
 130                 if (newsize <= NFS_OFFSET_MAX)
 131                         iap->ia_size = newsize;
 132                 else
 133                         iap->ia_size = NFS_OFFSET_MAX;
 134         }
 135         if ((tmp = ntohl(*p++)) == 1) { /* set to server time */
 136                 iap->ia_valid |= ATTR_ATIME;
 137         } else if (tmp == 2) {          /* set to client time */
 138                 iap->ia_valid |= ATTR_ATIME | ATTR_ATIME_SET;
 139                 iap->ia_atime.tv_sec = ntohl(*p++);
 140                 iap->ia_atime.tv_nsec = ntohl(*p++);
 141         }
 142         if ((tmp = ntohl(*p++)) == 1) { /* set to server time */
 143                 iap->ia_valid |= ATTR_MTIME;
 144         } else if (tmp == 2) {          /* set to client time */
 145                 iap->ia_valid |= ATTR_MTIME | ATTR_MTIME_SET;
 146                 iap->ia_mtime.tv_sec = ntohl(*p++);
 147                 iap->ia_mtime.tv_nsec = ntohl(*p++);
 148         }
 149         return p;
 150 }
 151
 152 static __be32 *encode_fsid(__be32 *p, struct svc_fh *fhp)
 153 {
 154         u64 f;
 155         switch(fsid_source(fhp)) {
 156         default:
 157         case FSIDSOURCE_DEV:
 158                 p = xdr_encode_hyper(p, (u64)huge_encode_dev
 159                                      (fhp->fh_dentry->d_inode->i_sb->s_dev));
 160                 break;
 161         case FSIDSOURCE_FSID:
 162                 p = xdr_encode_hyper(p, (u64) fhp->fh_export->ex_fsid);
 163                 break;
 164         case FSIDSOURCE_UUID:
 165                 f = ((u64*)fhp->fh_export->ex_uuid)[0];
 166                 f ^= ((u64*)fhp->fh_export->ex_uuid)[1];
 167                 p = xdr_encode_hyper(p, f);
 168                 break;
 169         }
 170         return p;
 171 }
 172
 173 static __be32 *
 174 encode_fattr3(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp,
 175               struct kstat *stat)
 176 {
 177         struct dentry   *dentry = fhp->fh_dentry;
 178         struct timespec time;
 179
 180         *p++ = htonl(nfs3_ftypes[(stat->mode & S_IFMT) >> 12]);
 181         *p++ = htonl((u32) stat->mode);
 182         *p++ = htonl((u32) stat->nlink);
 183         *p++ = htonl((u32) nfsd_ruid(rqstp, stat->uid));
 184         *p++ = htonl((u32) nfsd_rgid(rqstp, stat->gid));
 185         if (S_ISLNK(stat->mode) && stat->size > NFS3_MAXPATHLEN) {
 186                 p = xdr_encode_hyper(p, (u64) NFS3_MAXPATHLEN);
 187         } else {
 188                 p = xdr_encode_hyper(p, (u64) stat->size);
 189         }
 190         p = xdr_encode_hyper(p, ((u64)stat->blocks) << 9);
 191         *p++ = htonl((u32) MAJOR(stat->rdev));
 192         *p++ = htonl((u32) MINOR(stat->rdev));
 193         p = encode_fsid(p, fhp);
 194         p = xdr_encode_hyper(p, (u64) stat->ino);
 195         p = encode_time3(p, &stat->atime);
 196         lease_get_mtime(dentry->d_inode, &time);
 197         p = encode_time3(p, &time);
 198         p = encode_time3(p, &stat->ctime);
 199
 200         return p;
 201 }
 202
 203 static __be32 *
 204 encode_saved_post_attr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
 205 {
 206         struct inode    *inode = fhp->fh_dentry->d_inode;
 207
 208         /* Attributes to follow */
 209         *p++ = xdr_one;
 210
 211         *p++ = htonl(nfs3_ftypes[(fhp->fh_post_mode & S_IFMT) >> 12]);
 212         *p++ = htonl((u32) fhp->fh_post_mode);
 213         *p++ = htonl((u32) fhp->fh_post_nlink);
 214         *p++ = htonl((u32) nfsd_ruid(rqstp, fhp->fh_post_uid));
 215         *p++ = htonl((u32) nfsd_rgid(rqstp, fhp->fh_post_gid));
 216         if (S_ISLNK(fhp->fh_post_mode) && fhp->fh_post_size > NFS3_MAXPATHLEN) {
 217                 p = xdr_encode_hyper(p, (u64) NFS3_MAXPATHLEN);
 218         } else {
 219                 p = xdr_encode_hyper(p, (u64) fhp->fh_post_size);
 220         }
 221         p = xdr_encode_hyper(p, ((u64)fhp->fh_post_blocks) << 9);
 222         *p++ = fhp->fh_post_rdev[0];
 223         *p++ = fhp->fh_post_rdev[1];
 224         p = encode_fsid(p, fhp);
 225         p = xdr_encode_hyper(p, (u64) inode->i_ino);
 226         p = encode_time3(p, &fhp->fh_post_atime);
 227         p = encode_time3(p, &fhp->fh_post_mtime);
 228         p = encode_time3(p, &fhp->fh_post_ctime);
 229
 230         return p;
 231 }
 232
 233 /*
 234  * Encode post-operation attributes.
 235  * The inode may be NULL if the call failed because of a stale file
 236  * handle. In this case, no attributes are returned.
 237  */
 238 static __be32 *
 239 encode_post_op_attr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
 240 {
 241         struct dentry *dentry = fhp->fh_dentry;
 242         if (dentry && dentry->d_inode) {
 243                 int err;
 244                 struct kstat stat;
 245
 246                 err = vfs_getattr(fhp->fh_export->ex_mnt, dentry, &stat);
 247                 if (!err) {
 248                         *p++ = xdr_one;         /* attributes follow */
 249                         return encode_fattr3(rqstp, p, fhp, &stat);
 250                 }
 251         }
 252         *p++ = xdr_zero;
 253         return p;
 254 }
 255
 256 /* Helper for NFSv3 ACLs */
 257 __be32 *
 258 nfs3svc_encode_post_op_attr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
 259 {
 260         return encode_post_op_attr(rqstp, p, fhp);
 261 }
 262
 263 /*
 264  * Enocde weak cache consistency data
 265  */
 266 static __be32 *
 267 encode_wcc_data(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
 268 {
 269         struct dentry   *dentry = fhp->fh_dentry;
 270
 271         if (dentry && dentry->d_inode && fhp->fh_post_saved) {
 272                 if (fhp->fh_pre_saved) {
 273                         *p++ = xdr_one;
 274                         p = xdr_encode_hyper(p, (u64) fhp->fh_pre_size);
 275                         p = encode_time3(p, &fhp->fh_pre_mtime);
 276                         p = encode_time3(p, &fhp->fh_pre_ctime);
 277                 } else {
 278                         *p++ = xdr_zero;
 279                 }
 280                 return encode_saved_post_attr(rqstp, p, fhp);
 281         }
 282         /* no pre- or post-attrs */
 283         *p++ = xdr_zero;
 284         return encode_post_op_attr(rqstp, p, fhp);
 285 }
 286
 287
 288 /*
 289  * XDR decode functions
 290  */
 291 int
 292 nfs3svc_decode_fhandle(struct svc_rqst *rqstp, __be32 *p, struct nfsd_fhandle *args)
 293 {
 294         if (!(p = decode_fh(p, &args->fh)))
 295                 return 0;
 296         return xdr_argsize_check(rqstp, p);
 297 }
 298
 299 int
 300 nfs3svc_decode_sattrargs(struct svc_rqst *rqstp, __be32 *p,
 301                                         struct nfsd3_sattrargs *args)
 302 {
 303         if (!(p = decode_fh(p, &args->fh)))
 304                 return 0;
 305         p = decode_sattr3(p, &args->attrs);
 306
 307         if ((args->check_guard = ntohl(*p++)) != 0) {
 308                 struct timespec time;
 309                 p = decode_time3(p, &time);
 310                 args->guardtime = time.tv_sec;
 311         }
 312
 313         return xdr_argsize_check(rqstp, p);
 314 }
 315
 316 int
 317 nfs3svc_decode_diropargs(struct svc_rqst *rqstp, __be32 *p,
 318                                         struct nfsd3_diropargs *args)
 319 {
 320         if (!(p = decode_fh(p, &args->fh))
 321          || !(p = decode_filename(p, &args->name, &args->len)))
 322                 return 0;
 323
 324         return xdr_argsize_check(rqstp, p);
 325 }
 326
 327 int
 328 nfs3svc_decode_accessargs(struct svc_rqst *rqstp, __be32 *p,
 329                                         struct nfsd3_accessargs *args)
 330 {
 331         if (!(p = decode_fh(p, &args->fh)))
 332                 return 0;
 333         args->access = ntohl(*p++);
 334
 335         return xdr_argsize_check(rqstp, p);
 336 }
 337
 338 int
 339 nfs3svc_decode_readargs(struct svc_rqst *rqstp, __be32 *p,
 340                                         struct nfsd3_readargs *args)
 341 {
 342         unsigned int len;
 343         int v,pn;
 344         u32 max_blocksize = svc_max_payload(rqstp);
 345
 346         if (!(p = decode_fh(p, &args->fh)))
 347                 return 0;
 348         p = xdr_decode_hyper(p, &args->offset);
 349
 350         len = args->count = ntohl(*p++);
 351
 352         if (len > max_blocksize)
 353                 len = max_blocksize;
 354
 355         /* set up the kvec */
 356         v=0;
 357         while (len > 0) {
 358                 pn = rqstp->rq_resused++;
 359                 rqstp->rq_vec[v].iov_base = page_address(rqstp->rq_respages[pn]);
 360                 rqstp->rq_vec[v].iov_len = len < PAGE_SIZE? len : PAGE_SIZE;
 361                 len -= rqstp->rq_vec[v].iov_len;
 362                 v++;
 363         }
 364         args->vlen = v;
 365         return xdr_argsize_check(rqstp, p);
 366 }
 367
 368 int
 369 nfs3svc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p,
 370                                         struct nfsd3_writeargs *args)
 371 {
 372         unsigned int len, v, hdr, dlen;
 373         u32 max_blocksize = svc_max_payload(rqstp);
 374
 375         if (!(p = decode_fh(p, &args->fh)))
 376                 return 0;
 377         p = xdr_decode_hyper(p, &args->offset);
 378
 379         args->count = ntohl(*p++);
 380         args->stable = ntohl(*p++);
 381         len = args->len = ntohl(*p++);
 382         /*
 383          * The count must equal the amount of data passed.
 384          */
 385         if (args->count != args->len)
 386                 return 0;
 387
 388         /*
 389          * Check to make sure that we got the right number of
 390          * bytes.
 391          */
 392         hdr = (void*)p - rqstp->rq_arg.head[0].iov_base;
 393         dlen = rqstp->rq_arg.head[0].iov_len + rqstp->rq_arg.page_len
 394                 - hdr;
 395         /*
 396          * Round the length of the data which was specified up to
 397          * the next multiple of XDR units and then compare that
 398          * against the length which was actually received.
 399          */
 400         if (dlen != XDR_QUADLEN(len)*4)
 401                 return 0;
 402
 403         if (args->count > max_blocksize) {
 404                 args->count = max_blocksize;
 405                 len = args->len = max_blocksize;
 406         }
 407         rqstp->rq_vec[0].iov_base = (void*)p;
 408         rqstp->rq_vec[0].iov_len = rqstp->rq_arg.head[0].iov_len - hdr;
 409         v = 0;
 410         while (len > rqstp->rq_vec[v].iov_len) {
 411                 len -= rqstp->rq_vec[v].iov_len;
 412                 v++;
 413                 rqstp->rq_vec[v].iov_base = page_address(rqstp->rq_pages[v]);
 414                 rqstp->rq_vec[v].iov_len = PAGE_SIZE;
 415         }
 416         rqstp->rq_vec[v].iov_len = len;
 417         args->vlen = v + 1;
 418         return 1;
 419 }
 420
 421 int
 422 nfs3svc_decode_createargs(struct svc_rqst *rqstp, __be32 *p,
 423                                         struct nfsd3_createargs *args)
 424 {
 425         if (!(p = decode_fh(p, &args->fh))
 426          || !(p = decode_filename(p, &args->name, &args->len)))
 427                 return 0;
 428
 429         switch (args->createmode = ntohl(*p++)) {
 430         case NFS3_CREATE_UNCHECKED:
 431         case NFS3_CREATE_GUARDED:
 432                 p = decode_sattr3(p, &args->attrs);
 433                 break;
 434         case NFS3_CREATE_EXCLUSIVE:
 435                 args->verf = p;
 436                 p += 2;
 437                 break;
 438         default:
 439                 return 0;
 440         }
 441
 442         return xdr_argsize_check(rqstp, p);
 443 }
 444 int
 445 nfs3svc_decode_mkdirargs(struct svc_rqst *rqstp, __be32 *p,
 446                                         struct nfsd3_createargs *args)
 447 {
 448         if (!(p = decode_fh(p, &args->fh)) ||
 449             !(p = decode_filename(p, &args->name, &args->len)))
 450                 return 0;
 451         p = decode_sattr3(p, &args->attrs);
 452
 453         return xdr_argsize_check(rqstp, p);
 454 }
 455
 456 int
 457 nfs3svc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p,
 458                                         struct nfsd3_symlinkargs *args)
 459 {
 460         unsigned int len;
 461         int avail;
 462         char *old, *new;
 463         struct kvec *vec;
 464
 465         if (!(p = decode_fh(p, &args->ffh)) ||
 466             !(p = decode_filename(p, &args->fname, &args->flen))
 467                 )
 468                 return 0;
 469         p = decode_sattr3(p, &args->attrs);
 470
 471         /* now decode the pathname, which might be larger than the first page.
 472          * As we have to check for nul's anyway, we copy it into a new page
 473          * This page appears in the rq_res.pages list, but as pages_len is always
 474          * 0, it won't get in the way
 475          */
 476         len = ntohl(*p++);
 477         if (len == 0 || len > NFS3_MAXPATHLEN || len >= PAGE_SIZE)
 478                 return 0;
 479         args->tname = new =
 480                 page_address(rqstp->rq_respages[rqstp->rq_resused++]);
 481         args->tlen = len;
 482         /* first copy and check from the first page */
 483         old = (char*)p;
 484         vec = &rqstp->rq_arg.head[0];
 485         avail = vec->iov_len - (old - (char*)vec->iov_base);
 486         while (len && avail && *old) {
 487                 *new++ = *old++;
 488                 len--;
 489                 avail--;
 490         }
 491         /* now copy next page if there is one */
 492         if (len && !avail && rqstp->rq_arg.page_len) {
 493                 avail = rqstp->rq_arg.page_len;
 494                 if (avail > PAGE_SIZE) avail = PAGE_SIZE;
 495                 old = page_address(rqstp->rq_arg.pages[0]);
 496         }
 497         while (len && avail && *old) {
 498                 *new++ = *old++;
 499                 len--;
 500                 avail--;
 501         }
 502         *new = '\0';
 503         if (len)
 504                 return 0;
 505
 506         return 1;
 507 }
 508
 509 int
 510 nfs3svc_decode_mknodargs(struct svc_rqst *rqstp, __be32 *p,
 511                                         struct nfsd3_mknodargs *args)
 512 {
 513         if (!(p = decode_fh(p, &args->fh))
 514          || !(p = decode_filename(p, &args->name, &args->len)))
 515                 return 0;
 516
 517         args->ftype = ntohl(*p++);
 518
 519         if (args->ftype == NF3BLK  || args->ftype == NF3CHR
 520          || args->ftype == NF3SOCK || args->ftype == NF3FIFO)
 521                 p = decode_sattr3(p, &args->attrs);
 522
 523         if (args->ftype == NF3BLK || args->ftype == NF3CHR) {
 524                 args->major = ntohl(*p++);
 525                 args->minor = ntohl(*p++);
 526         }
 527
 528         return xdr_argsize_check(rqstp, p);
 529 }
 530
 531 int
 532 nfs3svc_decode_renameargs(struct svc_rqst *rqstp, __be32 *p,
 533                                         struct nfsd3_renameargs *args)
 534 {
 535         if (!(p = decode_fh(p, &args->ffh))
 536          || !(p = decode_filename(p, &args->fname, &args->flen))
 537          || !(p = decode_fh(p, &args->tfh))
 538          || !(p = decode_filename(p, &args->tname, &args->tlen)))
 539                 return 0;
 540
 541         return xdr_argsize_check(rqstp, p);
 542 }
 543
 544 int
 545 nfs3svc_decode_readlinkargs(struct svc_rqst *rqstp, __be32 *p,
 546                                         struct nfsd3_readlinkargs *args)
 547 {
 548         if (!(p = decode_fh(p, &args->fh)))
 549                 return 0;
 550         args->buffer =
 551                 page_address(rqstp->rq_respages[rqstp->rq_resused++]);
 552
 553         return xdr_argsize_check(rqstp, p);
 554 }
 555
 556 int
 557 nfs3svc_decode_linkargs(struct svc_rqst *rqstp, __be32 *p,
 558                                         struct nfsd3_linkargs *args)
 559 {
 560         if (!(p = decode_fh(p, &args->ffh))
 561          || !(p = decode_fh(p, &args->tfh))
 562          || !(p = decode_filename(p, &args->tname, &args->tlen)))
 563                 return 0;
 564
 565         return xdr_argsize_check(rqstp, p);
 566 }
 567
 568 int
 569 nfs3svc_decode_readdirargs(struct svc_rqst *rqstp, __be32 *p,
 570                                         struct nfsd3_readdirargs *args)
 571 {
 572         if (!(p = decode_fh(p, &args->fh)))
 573                 return 0;
 574         p = xdr_decode_hyper(p, &args->cookie);
 575         args->verf   = p; p += 2;
 576         args->dircount = ~0;
 577         args->count  = ntohl(*p++);
 578
 579         if (args->count > PAGE_SIZE)
 580                 args->count = PAGE_SIZE;
 581
 582         args->buffer =
 583                 page_address(rqstp->rq_respages[rqstp->rq_resused++]);
 584
 585         return xdr_argsize_check(rqstp, p);
 586 }
 587
 588 int
 589 nfs3svc_decode_readdirplusargs(struct svc_rqst *rqstp, __be32 *p,
 590                                         struct nfsd3_readdirargs *args)
 591 {
 592         int len, pn;
 593         u32 max_blocksize = svc_max_payload(rqstp);
 594
 595         if (!(p = decode_fh(p, &args->fh)))
 596                 return 0;
 597         p = xdr_decode_hyper(p, &args->cookie);
 598         args->verf     = p; p += 2;
 599         args->dircount = ntohl(*p++);
 600         args->count    = ntohl(*p++);
 601
 602         len = (args->count > max_blocksize) ? max_blocksize :
 603                                                   args->count;
 604         args->count = len;
 605
 606         while (len > 0) {
 607                 pn = rqstp->rq_resused++;
 608                 if (!args->buffer)
 609                         args->buffer = page_address(rqstp->rq_respages[pn]);
 610                 len -= PAGE_SIZE;
 611         }
 612
 613         return xdr_argsize_check(rqstp, p);
 614 }
 615
 616 int
 617 nfs3svc_decode_commitargs(struct svc_rqst *rqstp, __be32 *p,
 618                                         struct nfsd3_commitargs *args)
 619 {
 620         if (!(p = decode_fh(p, &args->fh)))
 621                 return 0;
 622         p = xdr_decode_hyper(p, &args->offset);
 623         args->count = ntohl(*p++);
 624
 625         return xdr_argsize_check(rqstp, p);
 626 }
 627
 628 /*
 629  * XDR encode functions
 630  */
 631 /*
 632  * There must be an encoding function for void results so svc_process
 633  * will work properly.
 634  */
 635 int
 636 nfs3svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
 637 {
 638         return xdr_ressize_check(rqstp, p);
 639 }
 640
 641 /* GETATTR */
 642 int
 643 nfs3svc_encode_attrstat(struct svc_rqst *rqstp, __be32 *p,
 644                                         struct nfsd3_attrstat *resp)
 645 {
 646         if (resp->status == 0)
 647                 p = encode_fattr3(rqstp, p, &resp->fh, &resp->stat);
 648         return xdr_ressize_check(rqstp, p);
 649 }
 650
 651 /* SETATTR, REMOVE, RMDIR */
 652 int
 653 nfs3svc_encode_wccstat(struct svc_rqst *rqstp, __be32 *p,
 654                                         struct nfsd3_attrstat *resp)
 655 {
 656         p = encode_wcc_data(rqstp, p, &resp->fh);
 657         return xdr_ressize_check(rqstp, p);
 658 }
 659
 660 /* LOOKUP */
 661 int
 662 nfs3svc_encode_diropres(struct svc_rqst *rqstp, __be32 *p,
 663                                         struct nfsd3_diropres *resp)
 664 {
 665         if (resp->status == 0) {
 666                 p = encode_fh(p, &resp->fh);
 667                 p = encode_post_op_attr(rqstp, p, &resp->fh);
 668         }
 669         p = encode_post_op_attr(rqstp, p, &resp->dirfh);
 670         return xdr_ressize_check(rqstp, p);
 671 }
 672
 673 /* ACCESS */
 674 int
 675 nfs3svc_encode_accessres(struct svc_rqst *rqstp, __be32 *p,
 676                                         struct nfsd3_accessres *resp)
 677 {
 678         p = encode_post_op_attr(rqstp, p, &resp->fh);
 679         if (resp->status == 0)
 680                 *p++ = htonl(resp->access);
 681         return xdr_ressize_check(rqstp, p);
 682 }
 683
 684 /* READLINK */
 685 int
 686 nfs3svc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p,
 687                                         struct nfsd3_readlinkres *resp)
 688 {
 689         p = encode_post_op_attr(rqstp, p, &resp->fh);
 690         if (resp->status == 0) {
 691                 *p++ = htonl(resp->len);
 692                 xdr_ressize_check(rqstp, p);
 693                 rqstp->rq_res.page_len = resp->len;
 694                 if (resp->len & 3) {
 695                         /* need to pad the tail */
 696                         rqstp->rq_res.tail[0].iov_base = p;
 697                         *p = 0;
 698                         rqstp->rq_res.tail[0].iov_len = 4 - (resp->len&3);
 699                 }
 700                 return 1;
 701         } else
 702                 return xdr_ressize_check(rqstp, p);
 703 }
 704
 705 /* READ */
 706 int
 707 nfs3svc_encode_readres(struct svc_rqst *rqstp, __be32 *p,
 708                                         struct nfsd3_readres *resp)
 709 {
 710         p = encode_post_op_attr(rqstp, p, &resp->fh);
 711         if (resp->status == 0) {
 712                 *p++ = htonl(resp->count);
 713                 *p++ = htonl(resp->eof);
 714                 *p++ = htonl(resp->count);      /* xdr opaque count */
 715                 xdr_ressize_check(rqstp, p);
 716                 /* now update rqstp->rq_res to reflect data aswell */
 717                 rqstp->rq_res.page_len = resp->count;
 718                 if (resp->count & 3) {
 719                         /* need to pad the tail */
 720                         rqstp->rq_res.tail[0].iov_base = p;
 721                         *p = 0;
 722                         rqstp->rq_res.tail[0].iov_len = 4 - (resp->count & 3);
 723                 }
 724                 return 1;
 725         } else
 726                 return xdr_ressize_check(rqstp, p);
 727 }
 728
 729 /* WRITE */
 730 int
 731 nfs3svc_encode_writeres(struct svc_rqst *rqstp, __be32 *p,
 732                                         struct nfsd3_writeres *resp)
 733 {
 734         p = encode_wcc_data(rqstp, p, &resp->fh);
 735         if (resp->status == 0) {
 736                 *p++ = htonl(resp->count);
 737                 *p++ = htonl(resp->committed);
 738                 *p++ = htonl(nfssvc_boot.tv_sec);
 739                 *p++ = htonl(nfssvc_boot.tv_usec);
 740         }
 741         return xdr_ressize_check(rqstp, p);
 742 }
 743
 744 /* CREATE, MKDIR, SYMLINK, MKNOD */
 745 int
 746 nfs3svc_encode_createres(struct svc_rqst *rqstp, __be32 *p,
 747                                         struct nfsd3_diropres *resp)
 748 {
 749         if (resp->status == 0) {
 750                 *p++ = xdr_one;
 751                 p = encode_fh(p, &resp->fh);
 752                 p = encode_post_op_attr(rqstp, p, &resp->fh);
 753         }
 754         p = encode_wcc_data(rqstp, p, &resp->dirfh);
 755         return xdr_ressize_check(rqstp, p);
 756 }
 757
 758 /* RENAME */
 759 int
 760 nfs3svc_encode_renameres(struct svc_rqst *rqstp, __be32 *p,
 761                                         struct nfsd3_renameres *resp)
 762 {
 763         p = encode_wcc_data(rqstp, p, &resp->ffh);
 764         p = encode_wcc_data(rqstp, p, &resp->tfh);
 765         return xdr_ressize_check(rqstp, p);
 766 }
 767
 768 /* LINK */
 769 int
 770 nfs3svc_encode_linkres(struct svc_rqst *rqstp, __be32 *p,
 771                                         struct nfsd3_linkres *resp)
 772 {
 773         p = encode_post_op_attr(rqstp, p, &resp->fh);
 774         p = encode_wcc_data(rqstp, p, &resp->tfh);
 775         return xdr_ressize_check(rqstp, p);
 776 }
 777
 778 /* READDIR */
 779 int
 780 nfs3svc_encode_readdirres(struct svc_rqst *rqstp, __be32 *p,
 781                                         struct nfsd3_readdirres *resp)
 782 {
 783         p = encode_post_op_attr(rqstp, p, &resp->fh);
 784
 785         if (resp->status == 0) {
 786                 /* stupid readdir cookie */
 787                 memcpy(p, resp->verf, 8); p += 2;
 788                 xdr_ressize_check(rqstp, p);
 789                 if (rqstp->rq_res.head[0].iov_len + (2<<2) > PAGE_SIZE)
 790                         return 1; /*No room for trailer */
 791                 rqstp->rq_res.page_len = (resp->count) << 2;
 792
 793                 /* add the 'tail' to the end of the 'head' page - page 0. */
 794                 rqstp->rq_res.tail[0].iov_base = p;
 795                 *p++ = 0;               /* no more entries */
 796                 *p++ = htonl(resp->common.err == nfserr_eof);
 797                 rqstp->rq_res.tail[0].iov_len = 2<<2;
 798                 return 1;
 799         } else
 800                 return xdr_ressize_check(rqstp, p);
 801 }
 802
 803 static __be32 *
 804 encode_entry_baggage(struct nfsd3_readdirres *cd, __be32 *p, const char *name,
 805              int namlen, ino_t ino)
 806 {
 807         *p++ = xdr_one;                          /* mark entry present */
 808         p    = xdr_encode_hyper(p, ino);         /* file id */
 809         p    = xdr_encode_array(p, name, namlen);/* name length & name */
 810
 811         cd->offset = p;                         /* remember pointer */
 812         p = xdr_encode_hyper(p, NFS_OFFSET_MAX);/* offset of next entry */
 813
 814         return p;
 815 }
 816
 817 static __be32 *
 818 encode_entryplus_baggage(struct nfsd3_readdirres *cd, __be32 *p,
 819                 struct svc_fh *fhp)
 820 {
 821                 p = encode_post_op_attr(cd->rqstp, p, fhp);
 822                 *p++ = xdr_one;                 /* yes, a file handle follows */
 823                 p = encode_fh(p, fhp);
 824                 fh_put(fhp);
 825                 return p;
 826 }
 827
 828 static int
 829 compose_entry_fh(struct nfsd3_readdirres *cd, struct svc_fh *fhp,
 830                 const char *name, int namlen)
 831 {
 832         struct svc_export       *exp;
 833         struct dentry           *dparent, *dchild;
 834         int rv = 0;
 835
 836         dparent = cd->fh.fh_dentry;
 837         exp  = cd->fh.fh_export;
 838
 839         fh_init(fhp, NFS3_FHSIZE);
 840         if (isdotent(name, namlen)) {
 841                 if (namlen == 2) {
 842                         dchild = dget_parent(dparent);
 843                         if (dchild == dparent) {
 844                                 /* filesystem root - cannot return filehandle for ".." */
 845                                 dput(dchild);
 846                                 return 1;
 847                         }
 848                 } else
 849                         dchild = dget(dparent);
 850         } else
 851                 dchild = lookup_one_len(name, dparent, namlen);
 852         if (IS_ERR(dchild))
 853                 return 1;
 854         if (d_mountpoint(dchild) ||
 855             fh_compose(fhp, exp, dchild, &cd->fh) != 0 ||
 856             !dchild->d_inode)
 857                 rv = 1;
 858         dput(dchild);
 859         return rv;
 860 }
 861
 862 /*
 863  * Encode a directory entry. This one works for both normal readdir
 864  * and readdirplus.
 865  * The normal readdir reply requires 2 (fileid) + 1 (stringlen)
 866  * + string + 2 (cookie) + 1 (next) words, i.e. 6 + strlen.
 867  *
 868  * The readdirplus baggage is 1+21 words for post_op_attr, plus the
 869  * file handle.
 870  */
 871
 872 #define NFS3_ENTRY_BAGGAGE      (2 + 1 + 2 + 1)
 873 #define NFS3_ENTRYPLUS_BAGGAGE  (1 + 21 + 1 + (NFS3_FHSIZE >> 2))
 874 static int
 875 encode_entry(struct readdir_cd *ccd, const char *name, int namlen,
 876              loff_t offset, ino_t ino, unsigned int d_type, int plus)
 877 {
 878         struct nfsd3_readdirres *cd = container_of(ccd, struct nfsd3_readdirres,
 879                                                         common);
 880         __be32          *p = cd->buffer;
 881         caddr_t         curr_page_addr = NULL;
 882         int             pn;             /* current page number */
 883         int             slen;           /* string (name) length */
 884         int             elen;           /* estimated entry length in words */
 885         int             num_entry_words = 0;    /* actual number of words */
 886
 887         if (cd->offset) {
 888                 u64 offset64 = offset;
 889
 890                 if (unlikely(cd->offset1)) {
 891                         /* we ended up with offset on a page boundary */
 892                         *cd->offset = htonl(offset64 >> 32);
 893                         *cd->offset1 = htonl(offset64 & 0xffffffff);
 894                         cd->offset1 = NULL;
 895                 } else {
 896                         xdr_encode_hyper(cd->offset, offset64);
 897                 }
 898         }
 899
 900         /*
 901         dprintk("encode_entry(%.*s @%ld%s)\n",
 902                 namlen, name, (long) offset, plus? " plus" : "");
 903          */
 904
 905         /* truncate filename if too long */
 906         if (namlen > NFS3_MAXNAMLEN)
 907                 namlen = NFS3_MAXNAMLEN;
 908
 909         slen = XDR_QUADLEN(namlen);
 910         elen = slen + NFS3_ENTRY_BAGGAGE
 911                 + (plus? NFS3_ENTRYPLUS_BAGGAGE : 0);
 912
 913         if (cd->buflen < elen) {
 914                 cd->common.err = nfserr_toosmall;
 915                 return -EINVAL;
 916         }
 917
 918         /* determine which page in rq_respages[] we are currently filling */
 919         for (pn=1; pn < cd->rqstp->rq_resused; pn++) {
 920                 curr_page_addr = page_address(cd->rqstp->rq_respages[pn]);
 921
 922                 if (((caddr_t)cd->buffer >= curr_page_addr) &&
 923                     ((caddr_t)cd->buffer <  curr_page_addr + PAGE_SIZE))
 924                         break;
 925         }
 926
 927         if ((caddr_t)(cd->buffer + elen) < (curr_page_addr + PAGE_SIZE)) {
 928                 /* encode entry in current page */
 929
 930                 p = encode_entry_baggage(cd, p, name, namlen, ino);
 931
 932                 /* throw in readdirplus baggage */
 933                 if (plus) {
 934                         struct svc_fh   fh;
 935
 936                         if (compose_entry_fh(cd, &fh, name, namlen) > 0) {
 937                                 *p++ = 0;
 938                                 *p++ = 0;
 939                         } else
 940                                 p = encode_entryplus_baggage(cd, p, &fh);
 941                 }
 942                 num_entry_words = p - cd->buffer;
 943         } else if (cd->rqstp->rq_respages[pn+1] != NULL) {
 944                 /* temporarily encode entry into next page, then move back to
 945                  * current and next page in rq_respages[] */
 946                 __be32 *p1, *tmp;
 947                 int len1, len2;
 948
 949                 /* grab next page for temporary storage of entry */
 950                 p1 = tmp = page_address(cd->rqstp->rq_respages[pn+1]);
 951
 952                 p1 = encode_entry_baggage(cd, p1, name, namlen, ino);
 953
 954                 /* throw in readdirplus baggage */
 955                 if (plus) {
 956                         struct svc_fh   fh;
 957
 958                         if (compose_entry_fh(cd, &fh, name, namlen) > 0) {
 959                                 /* zero out the filehandle */
 960                                 *p1++ = 0;
 961                                 *p1++ = 0;
 962                         } else
 963                                 p1 = encode_entryplus_baggage(cd, p1, &fh);
 964                 }
 965
 966                 /* determine entry word length and lengths to go in pages */
 967                 num_entry_words = p1 - tmp;
 968                 len1 = curr_page_addr + PAGE_SIZE - (caddr_t)cd->buffer;
 969                 if ((num_entry_words << 2) < len1) {
 970                         /* the actual number of words in the entry is less
 971                          * than elen and can still fit in the current page
 972                          */
 973                         memmove(p, tmp, num_entry_words << 2);
 974                         p += num_entry_words;
 975
 976                         /* update offset */
 977                         cd->offset = cd->buffer + (cd->offset - tmp);
 978                 } else {
 979                         unsigned int offset_r = (cd->offset - tmp) << 2;
 980
 981                         /* update pointer to offset location.
 982                          * This is a 64bit quantity, so we need to
 983                          * deal with 3 cases:
 984                          *  -   entirely in first page
 985                          *  -   entirely in second page
 986                          *  -   4 bytes in each page
 987                          */
 988                         if (offset_r + 8 <= len1) {
 989                                 cd->offset = p + (cd->offset - tmp);
 990                         } else if (offset_r >= len1) {
 991                                 cd->offset -= len1 >> 2;
 992                         } else {
 993                                 /* sitting on the fence */
 994                                 BUG_ON(offset_r != len1 - 4);
 995                                 cd->offset = p + (cd->offset - tmp);
 996                                 cd->offset1 = tmp;
 997                         }
 998
 999                         len2 = (num_entry_words << 2) - len1;
1000
1001                         /* move from temp page to current and next pages */
1002                         memmove(p, tmp, len1);
1003                         memmove(tmp, (caddr_t)tmp+len1, len2);
1004
1005                         p = tmp + (len2 >> 2);
1006                 }
1007         }
1008         else {
1009                 cd->common.err = nfserr_toosmall;
1010                 return -EINVAL;
1011         }
1012
1013         cd->buflen -= num_entry_words;
1014         cd->buffer = p;
1015         cd->common.err = nfs_ok;
1016         return 0;
1017
1018 }
1019
1020 int
1021 nfs3svc_encode_entry(void *cd, const char *name,
1022                      int namlen, loff_t offset, u64 ino, unsigned int d_type)
1023 {
1024         return encode_entry(cd, name, namlen, offset, ino, d_type, 0);
1025 }
1026
1027 int
1028 nfs3svc_encode_entry_plus(void *cd, const char *name,
1029                           int namlen, loff_t offset, u64 ino,
1030                           unsigned int d_type)
1031 {
1032         return encode_entry(cd, name, namlen, offset, ino, d_type, 1);
1033 }
1034
1035 /* FSSTAT */
1036 int
1037 nfs3svc_encode_fsstatres(struct svc_rqst *rqstp, __be32 *p,
1038                                         struct nfsd3_fsstatres *resp)
1039 {
1040         struct kstatfs  *s = &resp->stats;
1041         u64             bs = s->f_bsize;
1042
1043         *p++ = xdr_zero;        /* no post_op_attr */
1044
1045         if (resp->status == 0) {
1046                 p = xdr_encode_hyper(p, bs * s->f_blocks);      /* total bytes */
1047                 p = xdr_encode_hyper(p, bs * s->f_bfree);       /* free bytes */
1048                 p = xdr_encode_hyper(p, bs * s->f_bavail);      /* user available bytes */
1049                 p = xdr_encode_hyper(p, s->f_files);    /* total inodes */
1050                 p = xdr_encode_hyper(p, s->f_ffree);    /* free inodes */
1051                 p = xdr_encode_hyper(p, s->f_ffree);    /* user available inodes */
1052                 *p++ = htonl(resp->invarsec);   /* mean unchanged time */
1053         }
1054         return xdr_ressize_check(rqstp, p);
1055 }
1056
1057 /* FSINFO */
1058 int
1059 nfs3svc_encode_fsinfores(struct svc_rqst *rqstp, __be32 *p,
1060                                         struct nfsd3_fsinfores *resp)
1061 {
1062         *p++ = xdr_zero;        /* no post_op_attr */
1063
1064         if (resp->status == 0) {
1065                 *p++ = htonl(resp->f_rtmax);
1066                 *p++ = htonl(resp->f_rtpref);
1067                 *p++ = htonl(resp->f_rtmult);
1068                 *p++ = htonl(resp->f_wtmax);
1069                 *p++ = htonl(resp->f_wtpref);
1070                 *p++ = htonl(resp->f_wtmult);
1071                 *p++ = htonl(resp->f_dtpref);
1072                 p = xdr_encode_hyper(p, resp->f_maxfilesize);
1073                 *p++ = xdr_one;
1074                 *p++ = xdr_zero;
1075                 *p++ = htonl(resp->f_properties);
1076         }
1077
1078         return xdr_ressize_check(rqstp, p);
1079 }
1080
1081 /* PATHCONF */
1082 int
1083 nfs3svc_encode_pathconfres(struct svc_rqst *rqstp, __be32 *p,
1084                                         struct nfsd3_pathconfres *resp)
1085 {
1086         *p++ = xdr_zero;        /* no post_op_attr */
1087
1088         if (resp->status == 0) {
1089                 *p++ = htonl(resp->p_link_max);
1090                 *p++ = htonl(resp->p_name_max);
1091                 *p++ = htonl(resp->p_no_trunc);
1092                 *p++ = htonl(resp->p_chown_restricted);
1093                 *p++ = htonl(resp->p_case_insensitive);
1094                 *p++ = htonl(resp->p_case_preserving);
1095         }
1096
1097         return xdr_ressize_check(rqstp, p);
1098 }
1099
1100 /* COMMIT */
1101 int
1102 nfs3svc_encode_commitres(struct svc_rqst *rqstp, __be32 *p,
1103                                         struct nfsd3_commitres *resp)
1104 {
1105         p = encode_wcc_data(rqstp, p, &resp->fh);
1106         /* Write verifier */
1107         if (resp->status == 0) {
1108                 *p++ = htonl(nfssvc_boot.tv_sec);
1109                 *p++ = htonl(nfssvc_boot.tv_usec);
1110         }
1111         return xdr_ressize_check(rqstp, p);
1112 }
1113
1114 /*
1115  * XDR release functions
1116  */
1117 int
1118 nfs3svc_release_fhandle(struct svc_rqst *rqstp, __be32 *p,
1119                                         struct nfsd3_attrstat *resp)
1120 {
1121         fh_put(&resp->fh);
1122         return 1;
1123 }
1124
1125 int
1126 nfs3svc_release_fhandle2(struct svc_rqst *rqstp, __be32 *p,
1127                                         struct nfsd3_fhandle_pair *resp)
1128 {
1129         fh_put(&resp->fh1);
1130         fh_put(&resp->fh2);
1131         return 1;
1132 }