fs/nfsd/nfs3xdr.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * XDR support for nfsd/protocol version 3.
   4  *
   5  * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
   6  *
   7  * 2003-08-09 Jamie Lokier: Use htonl() for nanoseconds, not htons()!
   8  */
   9
  10 #include <linux/namei.h>
  11 #include <linux/sunrpc/svc_xprt.h>
  12 #include "xdr3.h"
  13 #include "auth.h"
  14 #include "netns.h"
  15 #include "vfs.h"
  16
  17 #define NFSDDBG_FACILITY                NFSDDBG_XDR
  18
  19
  20 /*
  21  * Mapping of S_IF* types to NFS file types
  22  */
  23 static u32      nfs3_ftypes[] = {
  24         NF3NON,  NF3FIFO, NF3CHR, NF3BAD,
  25         NF3DIR,  NF3BAD,  NF3BLK, NF3BAD,
  26         NF3REG,  NF3BAD,  NF3LNK, NF3BAD,
  27         NF3SOCK, NF3BAD,  NF3LNK, NF3BAD,
  28 };
  29
  30 /*
  31  * XDR functions for basic NFS types
  32  */
  33 static __be32 *
  34 encode_time3(__be32 *p, struct timespec *time)
  35 {
  36         *p++ = htonl((u32) time->tv_sec); *p++ = htonl(time->tv_nsec);
  37         return p;
  38 }
  39
  40 static __be32 *
  41 decode_time3(__be32 *p, struct timespec *time)
  42 {
  43         time->tv_sec = ntohl(*p++);
  44         time->tv_nsec = ntohl(*p++);
  45         return p;
  46 }
  47
  48 static __be32 *
  49 decode_fh(__be32 *p, struct svc_fh *fhp)
  50 {
  51         unsigned int size;
  52         fh_init(fhp, NFS3_FHSIZE);
  53         size = ntohl(*p++);
  54         if (size > NFS3_FHSIZE)
  55                 return NULL;
  56
  57         memcpy(&fhp->fh_handle.fh_base, p, size);
  58         fhp->fh_handle.fh_size = size;
  59         return p + XDR_QUADLEN(size);
  60 }
  61
  62 /* Helper function for NFSv3 ACL code */
  63 __be32 *nfs3svc_decode_fh(__be32 *p, struct svc_fh *fhp)
  64 {
  65         return decode_fh(p, fhp);
  66 }
  67
  68 static __be32 *
  69 encode_fh(__be32 *p, struct svc_fh *fhp)
  70 {
  71         unsigned int size = fhp->fh_handle.fh_size;
  72         *p++ = htonl(size);
  73         if (size) p[XDR_QUADLEN(size)-1]=0;
  74         memcpy(p, &fhp->fh_handle.fh_base, size);
  75         return p + XDR_QUADLEN(size);
  76 }
  77
  78 /*
  79  * Decode a file name and make sure that the path contains
  80  * no slashes or null bytes.
  81  */
  82 static __be32 *
  83 decode_filename(__be32 *p, char **namp, unsigned int *lenp)
  84 {
  85         char            *name;
  86         unsigned int    i;
  87
  88         if ((p = xdr_decode_string_inplace(p, namp, lenp, NFS3_MAXNAMLEN)) != NULL) {
  89                 for (i = 0, name = *namp; i < *lenp; i++, name++) {
  90                         if (*name == '\0' || *name == '/')
  91                                 return NULL;
  92                 }
  93         }
  94
  95         return p;
  96 }
  97
  98 static __be32 *
  99 decode_sattr3(__be32 *p, struct iattr *iap)
 100 {
 101         u32     tmp;
 102
 103         iap->ia_valid = 0;
 104
 105         if (*p++) {
 106                 iap->ia_valid |= ATTR_MODE;
 107                 iap->ia_mode = ntohl(*p++);
 108         }
 109         if (*p++) {
 110                 iap->ia_uid = make_kuid(&init_user_ns, ntohl(*p++));
 111                 if (uid_valid(iap->ia_uid))
 112                         iap->ia_valid |= ATTR_UID;
 113         }
 114         if (*p++) {
 115                 iap->ia_gid = make_kgid(&init_user_ns, ntohl(*p++));
 116                 if (gid_valid(iap->ia_gid))
 117                         iap->ia_valid |= ATTR_GID;
 118         }
 119         if (*p++) {
 120                 u64     newsize;
 121
 122                 iap->ia_valid |= ATTR_SIZE;
 123                 p = xdr_decode_hyper(p, &newsize);
 124                 iap->ia_size = min_t(u64, newsize, NFS_OFFSET_MAX);
 125         }
 126         if ((tmp = ntohl(*p++)) == 1) { /* set to server time */
 127                 iap->ia_valid |= ATTR_ATIME;
 128         } else if (tmp == 2) {          /* set to client time */
 129                 iap->ia_valid |= ATTR_ATIME | ATTR_ATIME_SET;
 130                 iap->ia_atime.tv_sec = ntohl(*p++);
 131                 iap->ia_atime.tv_nsec = ntohl(*p++);
 132         }
 133         if ((tmp = ntohl(*p++)) == 1) { /* set to server time */
 134                 iap->ia_valid |= ATTR_MTIME;
 135         } else if (tmp == 2) {          /* set to client time */
 136                 iap->ia_valid |= ATTR_MTIME | ATTR_MTIME_SET;
 137                 iap->ia_mtime.tv_sec = ntohl(*p++);
 138                 iap->ia_mtime.tv_nsec = ntohl(*p++);
 139         }
 140         return p;
 141 }
 142
 143 static __be32 *encode_fsid(__be32 *p, struct svc_fh *fhp)
 144 {
 145         u64 f;
 146         switch(fsid_source(fhp)) {
 147         default:
 148         case FSIDSOURCE_DEV:
 149                 p = xdr_encode_hyper(p, (u64)huge_encode_dev
 150                                      (fhp->fh_dentry->d_sb->s_dev));
 151                 break;
 152         case FSIDSOURCE_FSID:
 153                 p = xdr_encode_hyper(p, (u64) fhp->fh_export->ex_fsid);
 154                 break;
 155         case FSIDSOURCE_UUID:
 156                 f = ((u64*)fhp->fh_export->ex_uuid)[0];
 157                 f ^= ((u64*)fhp->fh_export->ex_uuid)[1];
 158                 p = xdr_encode_hyper(p, f);
 159                 break;
 160         }
 161         return p;
 162 }
 163
 164 static __be32 *
 165 encode_fattr3(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp,
 166               struct kstat *stat)
 167 {
 168         *p++ = htonl(nfs3_ftypes[(stat->mode & S_IFMT) >> 12]);
 169         *p++ = htonl((u32) (stat->mode & S_IALLUGO));
 170         *p++ = htonl((u32) stat->nlink);
 171         *p++ = htonl((u32) from_kuid(&init_user_ns, stat->uid));
 172         *p++ = htonl((u32) from_kgid(&init_user_ns, stat->gid));
 173         if (S_ISLNK(stat->mode) && stat->size > NFS3_MAXPATHLEN) {
 174                 p = xdr_encode_hyper(p, (u64) NFS3_MAXPATHLEN);
 175         } else {
 176                 p = xdr_encode_hyper(p, (u64) stat->size);
 177         }
 178         p = xdr_encode_hyper(p, ((u64)stat->blocks) << 9);
 179         *p++ = htonl((u32) MAJOR(stat->rdev));
 180         *p++ = htonl((u32) MINOR(stat->rdev));
 181         p = encode_fsid(p, fhp);
 182         p = xdr_encode_hyper(p, stat->ino);
 183         p = encode_time3(p, &stat->atime);
 184         p = encode_time3(p, &stat->mtime);
 185         p = encode_time3(p, &stat->ctime);
 186
 187         return p;
 188 }
 189
 190 static __be32 *
 191 encode_saved_post_attr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
 192 {
 193         /* Attributes to follow */
 194         *p++ = xdr_one;
 195         return encode_fattr3(rqstp, p, fhp, &fhp->fh_post_attr);
 196 }
 197
 198 /*
 199  * Encode post-operation attributes.
 200  * The inode may be NULL if the call failed because of a stale file
 201  * handle. In this case, no attributes are returned.
 202  */
 203 static __be32 *
 204 encode_post_op_attr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
 205 {
 206         struct dentry *dentry = fhp->fh_dentry;
 207         if (dentry && d_really_is_positive(dentry)) {
 208                 __be32 err;
 209                 struct kstat stat;
 210
 211                 err = fh_getattr(fhp, &stat);
 212                 if (!err) {
 213                         *p++ = xdr_one;         /* attributes follow */
 214                         lease_get_mtime(d_inode(dentry), &stat.mtime);
 215                         return encode_fattr3(rqstp, p, fhp, &stat);
 216                 }
 217         }
 218         *p++ = xdr_zero;
 219         return p;
 220 }
 221
 222 /* Helper for NFSv3 ACLs */
 223 __be32 *
 224 nfs3svc_encode_post_op_attr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
 225 {
 226         return encode_post_op_attr(rqstp, p, fhp);
 227 }
 228
 229 /*
 230  * Enocde weak cache consistency data
 231  */
 232 static __be32 *
 233 encode_wcc_data(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
 234 {
 235         struct dentry   *dentry = fhp->fh_dentry;
 236
 237         if (dentry && d_really_is_positive(dentry) && fhp->fh_post_saved) {
 238                 if (fhp->fh_pre_saved) {
 239                         *p++ = xdr_one;
 240                         p = xdr_encode_hyper(p, (u64) fhp->fh_pre_size);
 241                         p = encode_time3(p, &fhp->fh_pre_mtime);
 242                         p = encode_time3(p, &fhp->fh_pre_ctime);
 243                 } else {
 244                         *p++ = xdr_zero;
 245                 }
 246                 return encode_saved_post_attr(rqstp, p, fhp);
 247         }
 248         /* no pre- or post-attrs */
 249         *p++ = xdr_zero;
 250         return encode_post_op_attr(rqstp, p, fhp);
 251 }
 252
 253 /*
 254  * Fill in the pre_op attr for the wcc data
 255  */
 256 void fill_pre_wcc(struct svc_fh *fhp)
 257 {
 258         struct inode    *inode;
 259         struct kstat    stat;
 260         __be32 err;
 261
 262         if (fhp->fh_pre_saved)
 263                 return;
 264
 265         inode = d_inode(fhp->fh_dentry);
 266         err = fh_getattr(fhp, &stat);
 267         if (err) {
 268                 /* Grab the times from inode anyway */
 269                 stat.mtime = inode->i_mtime;
 270                 stat.ctime = inode->i_ctime;
 271                 stat.size  = inode->i_size;
 272         }
 273
 274         fhp->fh_pre_mtime = stat.mtime;
 275         fhp->fh_pre_ctime = stat.ctime;
 276         fhp->fh_pre_size  = stat.size;
 277         fhp->fh_pre_change = nfsd4_change_attribute(&stat, inode);
 278         fhp->fh_pre_saved = true;
 279 }
 280
 281 /*
 282  * Fill in the post_op attr for the wcc data
 283  */
 284 void fill_post_wcc(struct svc_fh *fhp)
 285 {
 286         __be32 err;
 287
 288         if (fhp->fh_post_saved)
 289                 printk("nfsd: inode locked twice during operation.\n");
 290
 291         err = fh_getattr(fhp, &fhp->fh_post_attr);
 292         fhp->fh_post_change = nfsd4_change_attribute(&fhp->fh_post_attr,
 293                                                      d_inode(fhp->fh_dentry));
 294         if (err) {
 295                 fhp->fh_post_saved = false;
 296                 /* Grab the ctime anyway - set_change_info might use it */
 297                 fhp->fh_post_attr.ctime = d_inode(fhp->fh_dentry)->i_ctime;
 298         } else
 299                 fhp->fh_post_saved = true;
 300 }
 301
 302 /*
 303  * XDR decode functions
 304  */
 305 int
 306 nfs3svc_decode_fhandle(struct svc_rqst *rqstp, __be32 *p)
 307 {
 308         struct nfsd_fhandle *args = rqstp->rq_argp;
 309
 310         p = decode_fh(p, &args->fh);
 311         if (!p)
 312                 return 0;
 313         return xdr_argsize_check(rqstp, p);
 314 }
 315
 316 int
 317 nfs3svc_decode_sattrargs(struct svc_rqst *rqstp, __be32 *p)
 318 {
 319         struct nfsd3_sattrargs *args = rqstp->rq_argp;
 320
 321         p = decode_fh(p, &args->fh);
 322         if (!p)
 323                 return 0;
 324         p = decode_sattr3(p, &args->attrs);
 325
 326         if ((args->check_guard = ntohl(*p++)) != 0) {
 327                 struct timespec time;
 328                 p = decode_time3(p, &time);
 329                 args->guardtime = time.tv_sec;
 330         }
 331
 332         return xdr_argsize_check(rqstp, p);
 333 }
 334
 335 int
 336 nfs3svc_decode_diropargs(struct svc_rqst *rqstp, __be32 *p)
 337 {
 338         struct nfsd3_diropargs *args = rqstp->rq_argp;
 339
 340         if (!(p = decode_fh(p, &args->fh))
 341          || !(p = decode_filename(p, &args->name, &args->len)))
 342                 return 0;
 343
 344         return xdr_argsize_check(rqstp, p);
 345 }
 346
 347 int
 348 nfs3svc_decode_accessargs(struct svc_rqst *rqstp, __be32 *p)
 349 {
 350         struct nfsd3_accessargs *args = rqstp->rq_argp;
 351
 352         p = decode_fh(p, &args->fh);
 353         if (!p)
 354                 return 0;
 355         args->access = ntohl(*p++);
 356
 357         return xdr_argsize_check(rqstp, p);
 358 }
 359
 360 int
 361 nfs3svc_decode_readargs(struct svc_rqst *rqstp, __be32 *p)
 362 {
 363         struct nfsd3_readargs *args = rqstp->rq_argp;
 364         unsigned int len;
 365         int v;
 366         u32 max_blocksize = svc_max_payload(rqstp);
 367
 368         p = decode_fh(p, &args->fh);
 369         if (!p)
 370                 return 0;
 371         p = xdr_decode_hyper(p, &args->offset);
 372
 373         args->count = ntohl(*p++);
 374         len = min(args->count, max_blocksize);
 375
 376         /* set up the kvec */
 377         v=0;
 378         while (len > 0) {
 379                 struct page *p = *(rqstp->rq_next_page++);
 380
 381                 rqstp->rq_vec[v].iov_base = page_address(p);
 382                 rqstp->rq_vec[v].iov_len = min_t(unsigned int, len, PAGE_SIZE);
 383                 len -= rqstp->rq_vec[v].iov_len;
 384                 v++;
 385         }
 386         args->vlen = v;
 387         return xdr_argsize_check(rqstp, p);
 388 }
 389
 390 int
 391 nfs3svc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p)
 392 {
 393         struct nfsd3_writeargs *args = rqstp->rq_argp;
 394         unsigned int len, v, hdr, dlen;
 395         u32 max_blocksize = svc_max_payload(rqstp);
 396         struct kvec *head = rqstp->rq_arg.head;
 397         struct kvec *tail = rqstp->rq_arg.tail;
 398
 399         p = decode_fh(p, &args->fh);
 400         if (!p)
 401                 return 0;
 402         p = xdr_decode_hyper(p, &args->offset);
 403
 404         args->count = ntohl(*p++);
 405         args->stable = ntohl(*p++);
 406         len = args->len = ntohl(*p++);
 407         if ((void *)p > head->iov_base + head->iov_len)
 408                 return 0;
 409         /*
 410          * The count must equal the amount of data passed.
 411          */
 412         if (args->count != args->len)
 413                 return 0;
 414
 415         /*
 416          * Check to make sure that we got the right number of
 417          * bytes.
 418          */
 419         hdr = (void*)p - head->iov_base;
 420         dlen = head->iov_len + rqstp->rq_arg.page_len + tail->iov_len - hdr;
 421         /*
 422          * Round the length of the data which was specified up to
 423          * the next multiple of XDR units and then compare that
 424          * against the length which was actually received.
 425          * Note that when RPCSEC/GSS (for example) is used, the
 426          * data buffer can be padded so dlen might be larger
 427          * than required.  It must never be smaller.
 428          */
 429         if (dlen < XDR_QUADLEN(len)*4)
 430                 return 0;
 431
 432         if (args->count > max_blocksize) {
 433                 args->count = max_blocksize;
 434                 len = args->len = max_blocksize;
 435         }
 436         rqstp->rq_vec[0].iov_base = (void*)p;
 437         rqstp->rq_vec[0].iov_len = head->iov_len - hdr;
 438         v = 0;
 439         while (len > rqstp->rq_vec[v].iov_len) {
 440                 len -= rqstp->rq_vec[v].iov_len;
 441                 v++;
 442                 rqstp->rq_vec[v].iov_base = page_address(rqstp->rq_pages[v]);
 443                 rqstp->rq_vec[v].iov_len = PAGE_SIZE;
 444         }
 445         rqstp->rq_vec[v].iov_len = len;
 446         args->vlen = v + 1;
 447         return 1;
 448 }
 449
 450 int
 451 nfs3svc_decode_createargs(struct svc_rqst *rqstp, __be32 *p)
 452 {
 453         struct nfsd3_createargs *args = rqstp->rq_argp;
 454
 455         if (!(p = decode_fh(p, &args->fh))
 456          || !(p = decode_filename(p, &args->name, &args->len)))
 457                 return 0;
 458
 459         switch (args->createmode = ntohl(*p++)) {
 460         case NFS3_CREATE_UNCHECKED:
 461         case NFS3_CREATE_GUARDED:
 462                 p = decode_sattr3(p, &args->attrs);
 463                 break;
 464         case NFS3_CREATE_EXCLUSIVE:
 465                 args->verf = p;
 466                 p += 2;
 467                 break;
 468         default:
 469                 return 0;
 470         }
 471
 472         return xdr_argsize_check(rqstp, p);
 473 }
 474
 475 int
 476 nfs3svc_decode_mkdirargs(struct svc_rqst *rqstp, __be32 *p)
 477 {
 478         struct nfsd3_createargs *args = rqstp->rq_argp;
 479
 480         if (!(p = decode_fh(p, &args->fh)) ||
 481             !(p = decode_filename(p, &args->name, &args->len)))
 482                 return 0;
 483         p = decode_sattr3(p, &args->attrs);
 484
 485         return xdr_argsize_check(rqstp, p);
 486 }
 487
 488 int
 489 nfs3svc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p)
 490 {
 491         struct nfsd3_symlinkargs *args = rqstp->rq_argp;
 492         unsigned int len, avail;
 493         char *old, *new;
 494         struct kvec *vec;
 495
 496         if (!(p = decode_fh(p, &args->ffh)) ||
 497             !(p = decode_filename(p, &args->fname, &args->flen))
 498                 )
 499                 return 0;
 500         p = decode_sattr3(p, &args->attrs);
 501
 502         /* now decode the pathname, which might be larger than the first page.
 503          * As we have to check for nul's anyway, we copy it into a new page
 504          * This page appears in the rq_res.pages list, but as pages_len is always
 505          * 0, it won't get in the way
 506          */
 507         len = ntohl(*p++);
 508         if (len == 0 || len > NFS3_MAXPATHLEN || len >= PAGE_SIZE)
 509                 return 0;
 510         args->tname = new = page_address(*(rqstp->rq_next_page++));
 511         args->tlen = len;
 512         /* first copy and check from the first page */
 513         old = (char*)p;
 514         vec = &rqstp->rq_arg.head[0];
 515         if ((void *)old > vec->iov_base + vec->iov_len)
 516                 return 0;
 517         avail = vec->iov_len - (old - (char*)vec->iov_base);
 518         while (len && avail && *old) {
 519                 *new++ = *old++;
 520                 len--;
 521                 avail--;
 522         }
 523         /* now copy next page if there is one */
 524         if (len && !avail && rqstp->rq_arg.page_len) {
 525                 avail = min_t(unsigned int, rqstp->rq_arg.page_len, PAGE_SIZE);
 526                 old = page_address(rqstp->rq_arg.pages[0]);
 527         }
 528         while (len && avail && *old) {
 529                 *new++ = *old++;
 530                 len--;
 531                 avail--;
 532         }
 533         *new = '\0';
 534         if (len)
 535                 return 0;
 536
 537         return 1;
 538 }
 539
 540 int
 541 nfs3svc_decode_mknodargs(struct svc_rqst *rqstp, __be32 *p)
 542 {
 543         struct nfsd3_mknodargs *args = rqstp->rq_argp;
 544
 545         if (!(p = decode_fh(p, &args->fh))
 546          || !(p = decode_filename(p, &args->name, &args->len)))
 547                 return 0;
 548
 549         args->ftype = ntohl(*p++);
 550
 551         if (args->ftype == NF3BLK  || args->ftype == NF3CHR
 552          || args->ftype == NF3SOCK || args->ftype == NF3FIFO)
 553                 p = decode_sattr3(p, &args->attrs);
 554
 555         if (args->ftype == NF3BLK || args->ftype == NF3CHR) {
 556                 args->major = ntohl(*p++);
 557                 args->minor = ntohl(*p++);
 558         }
 559
 560         return xdr_argsize_check(rqstp, p);
 561 }
 562
 563 int
 564 nfs3svc_decode_renameargs(struct svc_rqst *rqstp, __be32 *p)
 565 {
 566         struct nfsd3_renameargs *args = rqstp->rq_argp;
 567
 568         if (!(p = decode_fh(p, &args->ffh))
 569          || !(p = decode_filename(p, &args->fname, &args->flen))
 570          || !(p = decode_fh(p, &args->tfh))
 571          || !(p = decode_filename(p, &args->tname, &args->tlen)))
 572                 return 0;
 573
 574         return xdr_argsize_check(rqstp, p);
 575 }
 576
 577 int
 578 nfs3svc_decode_readlinkargs(struct svc_rqst *rqstp, __be32 *p)
 579 {
 580         struct nfsd3_readlinkargs *args = rqstp->rq_argp;
 581
 582         p = decode_fh(p, &args->fh);
 583         if (!p)
 584                 return 0;
 585         args->buffer = page_address(*(rqstp->rq_next_page++));
 586
 587         return xdr_argsize_check(rqstp, p);
 588 }
 589
 590 int
 591 nfs3svc_decode_linkargs(struct svc_rqst *rqstp, __be32 *p)
 592 {
 593         struct nfsd3_linkargs *args = rqstp->rq_argp;
 594
 595         if (!(p = decode_fh(p, &args->ffh))
 596          || !(p = decode_fh(p, &args->tfh))
 597          || !(p = decode_filename(p, &args->tname, &args->tlen)))
 598                 return 0;
 599
 600         return xdr_argsize_check(rqstp, p);
 601 }
 602
 603 int
 604 nfs3svc_decode_readdirargs(struct svc_rqst *rqstp, __be32 *p)
 605 {
 606         struct nfsd3_readdirargs *args = rqstp->rq_argp;
 607         p = decode_fh(p, &args->fh);
 608         if (!p)
 609                 return 0;
 610         p = xdr_decode_hyper(p, &args->cookie);
 611         args->verf   = p; p += 2;
 612         args->dircount = ~0;
 613         args->count  = ntohl(*p++);
 614         args->count  = min_t(u32, args->count, PAGE_SIZE);
 615         args->buffer = page_address(*(rqstp->rq_next_page++));
 616
 617         return xdr_argsize_check(rqstp, p);
 618 }
 619
 620 int
 621 nfs3svc_decode_readdirplusargs(struct svc_rqst *rqstp, __be32 *p)
 622 {
 623         struct nfsd3_readdirargs *args = rqstp->rq_argp;
 624         int len;
 625         u32 max_blocksize = svc_max_payload(rqstp);
 626
 627         p = decode_fh(p, &args->fh);
 628         if (!p)
 629                 return 0;
 630         p = xdr_decode_hyper(p, &args->cookie);
 631         args->verf     = p; p += 2;
 632         args->dircount = ntohl(*p++);
 633         args->count    = ntohl(*p++);
 634
 635         len = args->count = min(args->count, max_blocksize);
 636         while (len > 0) {
 637                 struct page *p = *(rqstp->rq_next_page++);
 638                 if (!args->buffer)
 639                         args->buffer = page_address(p);
 640                 len -= PAGE_SIZE;
 641         }
 642
 643         return xdr_argsize_check(rqstp, p);
 644 }
 645
 646 int
 647 nfs3svc_decode_commitargs(struct svc_rqst *rqstp, __be32 *p)
 648 {
 649         struct nfsd3_commitargs *args = rqstp->rq_argp;
 650         p = decode_fh(p, &args->fh);
 651         if (!p)
 652                 return 0;
 653         p = xdr_decode_hyper(p, &args->offset);
 654         args->count = ntohl(*p++);
 655
 656         return xdr_argsize_check(rqstp, p);
 657 }
 658
 659 /*
 660  * XDR encode functions
 661  */
 662 /*
 663  * There must be an encoding function for void results so svc_process
 664  * will work properly.
 665  */
 666 int
 667 nfs3svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p)
 668 {
 669         return xdr_ressize_check(rqstp, p);
 670 }
 671
 672 /* GETATTR */
 673 int
 674 nfs3svc_encode_attrstat(struct svc_rqst *rqstp, __be32 *p)
 675 {
 676         struct nfsd3_attrstat *resp = rqstp->rq_resp;
 677
 678         if (resp->status == 0) {
 679                 lease_get_mtime(d_inode(resp->fh.fh_dentry),
 680                                 &resp->stat.mtime);
 681                 p = encode_fattr3(rqstp, p, &resp->fh, &resp->stat);
 682         }
 683         return xdr_ressize_check(rqstp, p);
 684 }
 685
 686 /* SETATTR, REMOVE, RMDIR */
 687 int
 688 nfs3svc_encode_wccstat(struct svc_rqst *rqstp, __be32 *p)
 689 {
 690         struct nfsd3_attrstat *resp = rqstp->rq_resp;
 691
 692         p = encode_wcc_data(rqstp, p, &resp->fh);
 693         return xdr_ressize_check(rqstp, p);
 694 }
 695
 696 /* LOOKUP */
 697 int
 698 nfs3svc_encode_diropres(struct svc_rqst *rqstp, __be32 *p)
 699 {
 700         struct nfsd3_diropres *resp = rqstp->rq_resp;
 701
 702         if (resp->status == 0) {
 703                 p = encode_fh(p, &resp->fh);
 704                 p = encode_post_op_attr(rqstp, p, &resp->fh);
 705         }
 706         p = encode_post_op_attr(rqstp, p, &resp->dirfh);
 707         return xdr_ressize_check(rqstp, p);
 708 }
 709
 710 /* ACCESS */
 711 int
 712 nfs3svc_encode_accessres(struct svc_rqst *rqstp, __be32 *p)
 713 {
 714         struct nfsd3_accessres *resp = rqstp->rq_resp;
 715
 716         p = encode_post_op_attr(rqstp, p, &resp->fh);
 717         if (resp->status == 0)
 718                 *p++ = htonl(resp->access);
 719         return xdr_ressize_check(rqstp, p);
 720 }
 721
 722 /* READLINK */
 723 int
 724 nfs3svc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p)
 725 {
 726         struct nfsd3_readlinkres *resp = rqstp->rq_resp;
 727
 728         p = encode_post_op_attr(rqstp, p, &resp->fh);
 729         if (resp->status == 0) {
 730                 *p++ = htonl(resp->len);
 731                 xdr_ressize_check(rqstp, p);
 732                 rqstp->rq_res.page_len = resp->len;
 733                 if (resp->len & 3) {
 734                         /* need to pad the tail */
 735                         rqstp->rq_res.tail[0].iov_base = p;
 736                         *p = 0;
 737                         rqstp->rq_res.tail[0].iov_len = 4 - (resp->len&3);
 738                 }
 739                 return 1;
 740         } else
 741                 return xdr_ressize_check(rqstp, p);
 742 }
 743
 744 /* READ */
 745 int
 746 nfs3svc_encode_readres(struct svc_rqst *rqstp, __be32 *p)
 747 {
 748         struct nfsd3_readres *resp = rqstp->rq_resp;
 749
 750         p = encode_post_op_attr(rqstp, p, &resp->fh);
 751         if (resp->status == 0) {
 752                 *p++ = htonl(resp->count);
 753                 *p++ = htonl(resp->eof);
 754                 *p++ = htonl(resp->count);      /* xdr opaque count */
 755                 xdr_ressize_check(rqstp, p);
 756                 /* now update rqstp->rq_res to reflect data as well */
 757                 rqstp->rq_res.page_len = resp->count;
 758                 if (resp->count & 3) {
 759                         /* need to pad the tail */
 760                         rqstp->rq_res.tail[0].iov_base = p;
 761                         *p = 0;
 762                         rqstp->rq_res.tail[0].iov_len = 4 - (resp->count & 3);
 763                 }
 764                 return 1;
 765         } else
 766                 return xdr_ressize_check(rqstp, p);
 767 }
 768
 769 /* WRITE */
 770 int
 771 nfs3svc_encode_writeres(struct svc_rqst *rqstp, __be32 *p)
 772 {
 773         struct nfsd3_writeres *resp = rqstp->rq_resp;
 774         struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
 775
 776         p = encode_wcc_data(rqstp, p, &resp->fh);
 777         if (resp->status == 0) {
 778                 *p++ = htonl(resp->count);
 779                 *p++ = htonl(resp->committed);
 780                 /* unique identifier, y2038 overflow can be ignored */
 781                 *p++ = htonl((u32)nn->nfssvc_boot.tv_sec);
 782                 *p++ = htonl(nn->nfssvc_boot.tv_nsec);
 783         }
 784         return xdr_ressize_check(rqstp, p);
 785 }
 786
 787 /* CREATE, MKDIR, SYMLINK, MKNOD */
 788 int
 789 nfs3svc_encode_createres(struct svc_rqst *rqstp, __be32 *p)
 790 {
 791         struct nfsd3_diropres *resp = rqstp->rq_resp;
 792
 793         if (resp->status == 0) {
 794                 *p++ = xdr_one;
 795                 p = encode_fh(p, &resp->fh);
 796                 p = encode_post_op_attr(rqstp, p, &resp->fh);
 797         }
 798         p = encode_wcc_data(rqstp, p, &resp->dirfh);
 799         return xdr_ressize_check(rqstp, p);
 800 }
 801
 802 /* RENAME */
 803 int
 804 nfs3svc_encode_renameres(struct svc_rqst *rqstp, __be32 *p)
 805 {
 806         struct nfsd3_renameres *resp = rqstp->rq_resp;
 807
 808         p = encode_wcc_data(rqstp, p, &resp->ffh);
 809         p = encode_wcc_data(rqstp, p, &resp->tfh);
 810         return xdr_ressize_check(rqstp, p);
 811 }
 812
 813 /* LINK */
 814 int
 815 nfs3svc_encode_linkres(struct svc_rqst *rqstp, __be32 *p)
 816 {
 817         struct nfsd3_linkres *resp = rqstp->rq_resp;
 818
 819         p = encode_post_op_attr(rqstp, p, &resp->fh);
 820         p = encode_wcc_data(rqstp, p, &resp->tfh);
 821         return xdr_ressize_check(rqstp, p);
 822 }
 823
 824 /* READDIR */
 825 int
 826 nfs3svc_encode_readdirres(struct svc_rqst *rqstp, __be32 *p)
 827 {
 828         struct nfsd3_readdirres *resp = rqstp->rq_resp;
 829
 830         p = encode_post_op_attr(rqstp, p, &resp->fh);
 831
 832         if (resp->status == 0) {
 833                 /* stupid readdir cookie */
 834                 memcpy(p, resp->verf, 8); p += 2;
 835                 xdr_ressize_check(rqstp, p);
 836                 if (rqstp->rq_res.head[0].iov_len + (2<<2) > PAGE_SIZE)
 837                         return 1; /*No room for trailer */
 838                 rqstp->rq_res.page_len = (resp->count) << 2;
 839
 840                 /* add the 'tail' to the end of the 'head' page - page 0. */
 841                 rqstp->rq_res.tail[0].iov_base = p;
 842                 *p++ = 0;               /* no more entries */
 843                 *p++ = htonl(resp->common.err == nfserr_eof);
 844                 rqstp->rq_res.tail[0].iov_len = 2<<2;
 845                 return 1;
 846         } else
 847                 return xdr_ressize_check(rqstp, p);
 848 }
 849
 850 static __be32 *
 851 encode_entry_baggage(struct nfsd3_readdirres *cd, __be32 *p, const char *name,
 852              int namlen, u64 ino)
 853 {
 854         *p++ = xdr_one;                          /* mark entry present */
 855         p    = xdr_encode_hyper(p, ino);         /* file id */
 856         p    = xdr_encode_array(p, name, namlen);/* name length & name */
 857
 858         cd->offset = p;                         /* remember pointer */
 859         p = xdr_encode_hyper(p, NFS_OFFSET_MAX);/* offset of next entry */
 860
 861         return p;
 862 }
 863
 864 static __be32
 865 compose_entry_fh(struct nfsd3_readdirres *cd, struct svc_fh *fhp,
 866                  const char *name, int namlen, u64 ino)
 867 {
 868         struct svc_export       *exp;
 869         struct dentry           *dparent, *dchild;
 870         __be32 rv = nfserr_noent;
 871
 872         dparent = cd->fh.fh_dentry;
 873         exp  = cd->fh.fh_export;
 874
 875         if (isdotent(name, namlen)) {
 876                 if (namlen == 2) {
 877                         dchild = dget_parent(dparent);
 878                         /* filesystem root - cannot return filehandle for ".." */
 879                         if (dchild == dparent)
 880                                 goto out;
 881                 } else
 882                         dchild = dget(dparent);
 883         } else
 884                 dchild = lookup_one_len_unlocked(name, dparent, namlen);
 885         if (IS_ERR(dchild))
 886                 return rv;
 887         if (d_mountpoint(dchild))
 888                 goto out;
 889         if (d_really_is_negative(dchild))
 890                 goto out;
 891         if (dchild->d_inode->i_ino != ino)
 892                 goto out;
 893         rv = fh_compose(fhp, exp, dchild, &cd->fh);
 894 out:
 895         dput(dchild);
 896         return rv;
 897 }
 898
 899 static __be32 *encode_entryplus_baggage(struct nfsd3_readdirres *cd, __be32 *p, const char *name, int namlen, u64 ino)
 900 {
 901         struct svc_fh   *fh = &cd->scratch;
 902         __be32 err;
 903
 904         fh_init(fh, NFS3_FHSIZE);
 905         err = compose_entry_fh(cd, fh, name, namlen, ino);
 906         if (err) {
 907                 *p++ = 0;
 908                 *p++ = 0;
 909                 goto out;
 910         }
 911         p = encode_post_op_attr(cd->rqstp, p, fh);
 912         *p++ = xdr_one;                 /* yes, a file handle follows */
 913         p = encode_fh(p, fh);
 914 out:
 915         fh_put(fh);
 916         return p;
 917 }
 918
 919 /*
 920  * Encode a directory entry. This one works for both normal readdir
 921  * and readdirplus.
 922  * The normal readdir reply requires 2 (fileid) + 1 (stringlen)
 923  * + string + 2 (cookie) + 1 (next) words, i.e. 6 + strlen.
 924  *
 925  * The readdirplus baggage is 1+21 words for post_op_attr, plus the
 926  * file handle.
 927  */
 928
 929 #define NFS3_ENTRY_BAGGAGE      (2 + 1 + 2 + 1)
 930 #define NFS3_ENTRYPLUS_BAGGAGE  (1 + 21 + 1 + (NFS3_FHSIZE >> 2))
 931 static int
 932 encode_entry(struct readdir_cd *ccd, const char *name, int namlen,
 933              loff_t offset, u64 ino, unsigned int d_type, int plus)
 934 {
 935         struct nfsd3_readdirres *cd = container_of(ccd, struct nfsd3_readdirres,
 936                                                         common);
 937         __be32          *p = cd->buffer;
 938         caddr_t         curr_page_addr = NULL;
 939         struct page **  page;
 940         int             slen;           /* string (name) length */
 941         int             elen;           /* estimated entry length in words */
 942         int             num_entry_words = 0;    /* actual number of words */
 943
 944         if (cd->offset) {
 945                 u64 offset64 = offset;
 946
 947                 if (unlikely(cd->offset1)) {
 948                         /* we ended up with offset on a page boundary */
 949                         *cd->offset = htonl(offset64 >> 32);
 950                         *cd->offset1 = htonl(offset64 & 0xffffffff);
 951                         cd->offset1 = NULL;
 952                 } else {
 953                         xdr_encode_hyper(cd->offset, offset64);
 954                 }
 955         }
 956
 957         /*
 958         dprintk("encode_entry(%.*s @%ld%s)\n",
 959                 namlen, name, (long) offset, plus? " plus" : "");
 960          */
 961
 962         /* truncate filename if too long */
 963         namlen = min(namlen, NFS3_MAXNAMLEN);
 964
 965         slen = XDR_QUADLEN(namlen);
 966         elen = slen + NFS3_ENTRY_BAGGAGE
 967                 + (plus? NFS3_ENTRYPLUS_BAGGAGE : 0);
 968
 969         if (cd->buflen < elen) {
 970                 cd->common.err = nfserr_toosmall;
 971                 return -EINVAL;
 972         }
 973
 974         /* determine which page in rq_respages[] we are currently filling */
 975         for (page = cd->rqstp->rq_respages + 1;
 976                                 page < cd->rqstp->rq_next_page; page++) {
 977                 curr_page_addr = page_address(*page);
 978
 979                 if (((caddr_t)cd->buffer >= curr_page_addr) &&
 980                     ((caddr_t)cd->buffer <  curr_page_addr + PAGE_SIZE))
 981                         break;
 982         }
 983
 984         if ((caddr_t)(cd->buffer + elen) < (curr_page_addr + PAGE_SIZE)) {
 985                 /* encode entry in current page */
 986
 987                 p = encode_entry_baggage(cd, p, name, namlen, ino);
 988
 989                 if (plus)
 990                         p = encode_entryplus_baggage(cd, p, name, namlen, ino);
 991                 num_entry_words = p - cd->buffer;
 992         } else if (*(page+1) != NULL) {
 993                 /* temporarily encode entry into next page, then move back to
 994                  * current and next page in rq_respages[] */
 995                 __be32 *p1, *tmp;
 996                 int len1, len2;
 997
 998                 /* grab next page for temporary storage of entry */
 999                 p1 = tmp = page_address(*(page+1));
1000
1001                 p1 = encode_entry_baggage(cd, p1, name, namlen, ino);
1002
1003                 if (plus)
1004                         p1 = encode_entryplus_baggage(cd, p1, name, namlen, ino);
1005
1006                 /* determine entry word length and lengths to go in pages */
1007                 num_entry_words = p1 - tmp;
1008                 len1 = curr_page_addr + PAGE_SIZE - (caddr_t)cd->buffer;
1009                 if ((num_entry_words << 2) < len1) {
1010                         /* the actual number of words in the entry is less
1011                          * than elen and can still fit in the current page
1012                          */
1013                         memmove(p, tmp, num_entry_words << 2);
1014                         p += num_entry_words;
1015
1016                         /* update offset */
1017                         cd->offset = cd->buffer + (cd->offset - tmp);
1018                 } else {
1019                         unsigned int offset_r = (cd->offset - tmp) << 2;
1020
1021                         /* update pointer to offset location.
1022                          * This is a 64bit quantity, so we need to
1023                          * deal with 3 cases:
1024                          *  -   entirely in first page
1025                          *  -   entirely in second page
1026                          *  -   4 bytes in each page
1027                          */
1028                         if (offset_r + 8 <= len1) {
1029                                 cd->offset = p + (cd->offset - tmp);
1030                         } else if (offset_r >= len1) {
1031                                 cd->offset -= len1 >> 2;
1032                         } else {
1033                                 /* sitting on the fence */
1034                                 BUG_ON(offset_r != len1 - 4);
1035                                 cd->offset = p + (cd->offset - tmp);
1036                                 cd->offset1 = tmp;
1037                         }
1038
1039                         len2 = (num_entry_words << 2) - len1;
1040
1041                         /* move from temp page to current and next pages */
1042                         memmove(p, tmp, len1);
1043                         memmove(tmp, (caddr_t)tmp+len1, len2);
1044
1045                         p = tmp + (len2 >> 2);
1046                 }
1047         }
1048         else {
1049                 cd->common.err = nfserr_toosmall;
1050                 return -EINVAL;
1051         }
1052
1053         cd->buflen -= num_entry_words;
1054         cd->buffer = p;
1055         cd->common.err = nfs_ok;
1056         return 0;
1057
1058 }
1059
1060 int
1061 nfs3svc_encode_entry(void *cd, const char *name,
1062                      int namlen, loff_t offset, u64 ino, unsigned int d_type)
1063 {
1064         return encode_entry(cd, name, namlen, offset, ino, d_type, 0);
1065 }
1066
1067 int
1068 nfs3svc_encode_entry_plus(void *cd, const char *name,
1069                           int namlen, loff_t offset, u64 ino,
1070                           unsigned int d_type)
1071 {
1072         return encode_entry(cd, name, namlen, offset, ino, d_type, 1);
1073 }
1074
1075 /* FSSTAT */
1076 int
1077 nfs3svc_encode_fsstatres(struct svc_rqst *rqstp, __be32 *p)
1078 {
1079         struct nfsd3_fsstatres *resp = rqstp->rq_resp;
1080         struct kstatfs  *s = &resp->stats;
1081         u64             bs = s->f_bsize;
1082
1083         *p++ = xdr_zero;        /* no post_op_attr */
1084
1085         if (resp->status == 0) {
1086                 p = xdr_encode_hyper(p, bs * s->f_blocks);      /* total bytes */
1087                 p = xdr_encode_hyper(p, bs * s->f_bfree);       /* free bytes */
1088                 p = xdr_encode_hyper(p, bs * s->f_bavail);      /* user available bytes */
1089                 p = xdr_encode_hyper(p, s->f_files);    /* total inodes */
1090                 p = xdr_encode_hyper(p, s->f_ffree);    /* free inodes */
1091                 p = xdr_encode_hyper(p, s->f_ffree);    /* user available inodes */
1092                 *p++ = htonl(resp->invarsec);   /* mean unchanged time */
1093         }
1094         return xdr_ressize_check(rqstp, p);
1095 }
1096
1097 /* FSINFO */
1098 int
1099 nfs3svc_encode_fsinfores(struct svc_rqst *rqstp, __be32 *p)
1100 {
1101         struct nfsd3_fsinfores *resp = rqstp->rq_resp;
1102
1103         *p++ = xdr_zero;        /* no post_op_attr */
1104
1105         if (resp->status == 0) {
1106                 *p++ = htonl(resp->f_rtmax);
1107                 *p++ = htonl(resp->f_rtpref);
1108                 *p++ = htonl(resp->f_rtmult);
1109                 *p++ = htonl(resp->f_wtmax);
1110                 *p++ = htonl(resp->f_wtpref);
1111                 *p++ = htonl(resp->f_wtmult);
1112                 *p++ = htonl(resp->f_dtpref);
1113                 p = xdr_encode_hyper(p, resp->f_maxfilesize);
1114                 *p++ = xdr_one;
1115                 *p++ = xdr_zero;
1116                 *p++ = htonl(resp->f_properties);
1117         }
1118
1119         return xdr_ressize_check(rqstp, p);
1120 }
1121
1122 /* PATHCONF */
1123 int
1124 nfs3svc_encode_pathconfres(struct svc_rqst *rqstp, __be32 *p)
1125 {
1126         struct nfsd3_pathconfres *resp = rqstp->rq_resp;
1127
1128         *p++ = xdr_zero;        /* no post_op_attr */
1129
1130         if (resp->status == 0) {
1131                 *p++ = htonl(resp->p_link_max);
1132                 *p++ = htonl(resp->p_name_max);
1133                 *p++ = htonl(resp->p_no_trunc);
1134                 *p++ = htonl(resp->p_chown_restricted);
1135                 *p++ = htonl(resp->p_case_insensitive);
1136                 *p++ = htonl(resp->p_case_preserving);
1137         }
1138
1139         return xdr_ressize_check(rqstp, p);
1140 }
1141
1142 /* COMMIT */
1143 int
1144 nfs3svc_encode_commitres(struct svc_rqst *rqstp, __be32 *p)
1145 {
1146         struct nfsd3_commitres *resp = rqstp->rq_resp;
1147         struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
1148
1149         p = encode_wcc_data(rqstp, p, &resp->fh);
1150         /* Write verifier */
1151         if (resp->status == 0) {
1152                 /* unique identifier, y2038 overflow can be ignored */
1153                 *p++ = htonl((u32)nn->nfssvc_boot.tv_sec);
1154                 *p++ = htonl(nn->nfssvc_boot.tv_nsec);
1155         }
1156         return xdr_ressize_check(rqstp, p);
1157 }
1158
1159 /*
1160  * XDR release functions
1161  */
1162 void
1163 nfs3svc_release_fhandle(struct svc_rqst *rqstp)
1164 {
1165         struct nfsd3_attrstat *resp = rqstp->rq_resp;
1166
1167         fh_put(&resp->fh);
1168 }
1169
1170 void
1171 nfs3svc_release_fhandle2(struct svc_rqst *rqstp)
1172 {
1173         struct nfsd3_fhandle_pair *resp = rqstp->rq_resp;
1174
1175         fh_put(&resp->fh1);
1176         fh_put(&resp->fh2);
1177 }