1 /* 2 * NFS server file handle treatment. 3 * 4 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> 5 * Portions Copyright (C) 1999 G. Allen Morris III <gam3@acm.org> 6 * Extensive rewrite by Neil Brown <neilb@cse.unsw.edu.au> Southern-Spring 1999 7 * ... and again Southern-Winter 2001 to support export_operations 8 */ 9 10 #include <linux/exportfs.h> 11 12 #include <linux/sunrpc/svcauth_gss.h> 13 #include "nfsd.h" 14 #include "vfs.h" 15 #include "auth.h" 16 17 #define NFSDDBG_FACILITY NFSDDBG_FH 18 19 20 /* 21 * our acceptability function. 22 * if NOSUBTREECHECK, accept anything 23 * if not, require that we can walk up to exp->ex_dentry 24 * doing some checks on the 'x' bits 25 */ 26 static int nfsd_acceptable(void *expv, struct dentry *dentry) 27 { 28 struct svc_export *exp = expv; 29 int rv; 30 struct dentry *tdentry; 31 struct dentry *parent; 32 33 if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) 34 return 1; 35 36 tdentry = dget(dentry); 37 while (tdentry != exp->ex_path.dentry && !IS_ROOT(tdentry)) { 38 /* make sure parents give x permission to user */ 39 int err; 40 parent = dget_parent(tdentry); 41 err = inode_permission(parent->d_inode, MAY_EXEC); 42 if (err < 0) { 43 dput(parent); 44 break; 45 } 46 dput(tdentry); 47 tdentry = parent; 48 } 49 if (tdentry != exp->ex_path.dentry) 50 dprintk("nfsd_acceptable failed at %p %s\n", tdentry, tdentry->d_name.name); 51 rv = (tdentry == exp->ex_path.dentry); 52 dput(tdentry); 53 return rv; 54 } 55 56 /* Type check. The correct error return for type mismatches does not seem to be 57 * generally agreed upon. SunOS seems to use EISDIR if file isn't S_IFREG; a 58 * comment in the NFSv3 spec says this is incorrect (implementation notes for 59 * the write call). 60 */ 61 static inline __be32 62 nfsd_mode_check(struct svc_rqst *rqstp, umode_t mode, int type) 63 { 64 /* Type can be negative when creating hardlinks - not to a dir */ 65 if (type > 0 && (mode & S_IFMT) != type) { 66 if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK) 67 return nfserr_symlink; 68 else if (type == S_IFDIR) 69 return nfserr_notdir; 70 else if ((mode & S_IFMT) == S_IFDIR) 71 return nfserr_isdir; 72 else 73 return nfserr_inval; 74 } 75 if (type < 0 && (mode & S_IFMT) == -type) { 76 if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK) 77 return nfserr_symlink; 78 else if (type == -S_IFDIR) 79 return nfserr_isdir; 80 else 81 return nfserr_notdir; 82 } 83 return 0; 84 } 85 86 static __be32 nfsd_setuser_and_check_port(struct svc_rqst *rqstp, 87 struct svc_export *exp) 88 { 89 int flags = nfsexp_flags(rqstp, exp); 90 91 /* Check if the request originated from a secure port. */ 92 if (!rqstp->rq_secure && !(flags & NFSEXP_INSECURE_PORT)) { 93 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]); 94 dprintk(KERN_WARNING 95 "nfsd: request from insecure port %s!\n", 96 svc_print_addr(rqstp, buf, sizeof(buf))); 97 return nfserr_perm; 98 } 99 100 /* Set user creds for this exportpoint */ 101 return nfserrno(nfsd_setuser(rqstp, exp)); 102 } 103 104 static inline __be32 check_pseudo_root(struct svc_rqst *rqstp, 105 struct dentry *dentry, struct svc_export *exp) 106 { 107 if (!(exp->ex_flags & NFSEXP_V4ROOT)) 108 return nfs_ok; 109 /* 110 * v2/v3 clients have no need for the V4ROOT export--they use 111 * the mount protocl instead; also, further V4ROOT checks may be 112 * in v4-specific code, in which case v2/v3 clients could bypass 113 * them. 114 */ 115 if (!nfsd_v4client(rqstp)) 116 return nfserr_stale; 117 /* 118 * We're exposing only the directories and symlinks that have to be 119 * traversed on the way to real exports: 120 */ 121 if (unlikely(!S_ISDIR(dentry->d_inode->i_mode) && 122 !S_ISLNK(dentry->d_inode->i_mode))) 123 return nfserr_stale; 124 /* 125 * A pseudoroot export gives permission to access only one 126 * single directory; the kernel has to make another upcall 127 * before granting access to anything else under it: 128 */ 129 if (unlikely(dentry != exp->ex_path.dentry)) 130 return nfserr_stale; 131 return nfs_ok; 132 } 133 134 /* 135 * Use the given filehandle to look up the corresponding export and 136 * dentry. On success, the results are used to set fh_export and 137 * fh_dentry. 138 */ 139 static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp) 140 { 141 struct knfsd_fh *fh = &fhp->fh_handle; 142 struct fid *fid = NULL, sfid; 143 struct svc_export *exp; 144 struct dentry *dentry; 145 int fileid_type; 146 int data_left = fh->fh_size/4; 147 __be32 error; 148 149 error = nfserr_stale; 150 if (rqstp->rq_vers > 2) 151 error = nfserr_badhandle; 152 if (rqstp->rq_vers == 4 && fh->fh_size == 0) 153 return nfserr_nofilehandle; 154 155 if (fh->fh_version == 1) { 156 int len; 157 158 if (--data_left < 0) 159 return error; 160 if (fh->fh_auth_type != 0) 161 return error; 162 len = key_len(fh->fh_fsid_type) / 4; 163 if (len == 0) 164 return error; 165 if (fh->fh_fsid_type == FSID_MAJOR_MINOR) { 166 /* deprecated, convert to type 3 */ 167 len = key_len(FSID_ENCODE_DEV)/4; 168 fh->fh_fsid_type = FSID_ENCODE_DEV; 169 fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl(fh->fh_fsid[0]), ntohl(fh->fh_fsid[1]))); 170 fh->fh_fsid[1] = fh->fh_fsid[2]; 171 } 172 data_left -= len; 173 if (data_left < 0) 174 return error; 175 exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_auth); 176 fid = (struct fid *)(fh->fh_auth + len); 177 } else { 178 __u32 tfh[2]; 179 dev_t xdev; 180 ino_t xino; 181 182 if (fh->fh_size != NFS_FHSIZE) 183 return error; 184 /* assume old filehandle format */ 185 xdev = old_decode_dev(fh->ofh_xdev); 186 xino = u32_to_ino_t(fh->ofh_xino); 187 mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL); 188 exp = rqst_exp_find(rqstp, FSID_DEV, tfh); 189 } 190 191 error = nfserr_stale; 192 if (PTR_ERR(exp) == -ENOENT) 193 return error; 194 195 if (IS_ERR(exp)) 196 return nfserrno(PTR_ERR(exp)); 197 198 if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) { 199 /* Elevate privileges so that the lack of 'r' or 'x' 200 * permission on some parent directory will 201 * not stop exportfs_decode_fh from being able 202 * to reconnect a directory into the dentry cache. 203 * The same problem can affect "SUBTREECHECK" exports, 204 * but as nfsd_acceptable depends on correct 205 * access control settings being in effect, we cannot 206 * fix that case easily. 207 */ 208 struct cred *new = prepare_creds(); 209 if (!new) 210 return nfserrno(-ENOMEM); 211 new->cap_effective = 212 cap_raise_nfsd_set(new->cap_effective, 213 new->cap_permitted); 214 put_cred(override_creds(new)); 215 put_cred(new); 216 } else { 217 error = nfsd_setuser_and_check_port(rqstp, exp); 218 if (error) 219 goto out; 220 } 221 222 /* 223 * Look up the dentry using the NFS file handle. 224 */ 225 error = nfserr_stale; 226 if (rqstp->rq_vers > 2) 227 error = nfserr_badhandle; 228 229 if (fh->fh_version != 1) { 230 sfid.i32.ino = fh->ofh_ino; 231 sfid.i32.gen = fh->ofh_generation; 232 sfid.i32.parent_ino = fh->ofh_dirino; 233 fid = &sfid; 234 data_left = 3; 235 if (fh->ofh_dirino == 0) 236 fileid_type = FILEID_INO32_GEN; 237 else 238 fileid_type = FILEID_INO32_GEN_PARENT; 239 } else 240 fileid_type = fh->fh_fileid_type; 241 242 if (fileid_type == FILEID_ROOT) 243 dentry = dget(exp->ex_path.dentry); 244 else { 245 dentry = exportfs_decode_fh(exp->ex_path.mnt, fid, 246 data_left, fileid_type, 247 nfsd_acceptable, exp); 248 } 249 if (dentry == NULL) 250 goto out; 251 if (IS_ERR(dentry)) { 252 if (PTR_ERR(dentry) != -EINVAL) 253 error = nfserrno(PTR_ERR(dentry)); 254 goto out; 255 } 256 257 if (S_ISDIR(dentry->d_inode->i_mode) && 258 (dentry->d_flags & DCACHE_DISCONNECTED)) { 259 printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %s/%s\n", 260 dentry->d_parent->d_name.name, dentry->d_name.name); 261 } 262 263 fhp->fh_dentry = dentry; 264 fhp->fh_export = exp; 265 return 0; 266 out: 267 exp_put(exp); 268 return error; 269 } 270 271 /** 272 * fh_verify - filehandle lookup and access checking 273 * @rqstp: pointer to current rpc request 274 * @fhp: filehandle to be verified 275 * @type: expected type of object pointed to by filehandle 276 * @access: type of access needed to object 277 * 278 * Look up a dentry from the on-the-wire filehandle, check the client's 279 * access to the export, and set the current task's credentials. 280 * 281 * Regardless of success or failure of fh_verify(), fh_put() should be 282 * called on @fhp when the caller is finished with the filehandle. 283 * 284 * fh_verify() may be called multiple times on a given filehandle, for 285 * example, when processing an NFSv4 compound. The first call will look 286 * up a dentry using the on-the-wire filehandle. Subsequent calls will 287 * skip the lookup and just perform the other checks and possibly change 288 * the current task's credentials. 289 * 290 * @type specifies the type of object expected using one of the S_IF* 291 * constants defined in include/linux/stat.h. The caller may use zero 292 * to indicate that it doesn't care, or a negative integer to indicate 293 * that it expects something not of the given type. 294 * 295 * @access is formed from the NFSD_MAY_* constants defined in 296 * include/linux/nfsd/nfsd.h. 297 */ 298 __be32 299 fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, int access) 300 { 301 struct svc_export *exp; 302 struct dentry *dentry; 303 __be32 error; 304 305 dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp)); 306 307 if (!fhp->fh_dentry) { 308 error = nfsd_set_fh_dentry(rqstp, fhp); 309 if (error) 310 goto out; 311 } 312 dentry = fhp->fh_dentry; 313 exp = fhp->fh_export; 314 /* 315 * We still have to do all these permission checks, even when 316 * fh_dentry is already set: 317 * - fh_verify may be called multiple times with different 318 * "access" arguments (e.g. nfsd_proc_create calls 319 * fh_verify(...,NFSD_MAY_EXEC) first, then later (in 320 * nfsd_create) calls fh_verify(...,NFSD_MAY_CREATE). 321 * - in the NFSv4 case, the filehandle may have been filled 322 * in by fh_compose, and given a dentry, but further 323 * compound operations performed with that filehandle 324 * still need permissions checks. In the worst case, a 325 * mountpoint crossing may have changed the export 326 * options, and we may now need to use a different uid 327 * (for example, if different id-squashing options are in 328 * effect on the new filesystem). 329 */ 330 error = check_pseudo_root(rqstp, dentry, exp); 331 if (error) 332 goto out; 333 334 error = nfsd_setuser_and_check_port(rqstp, exp); 335 if (error) 336 goto out; 337 338 error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type); 339 if (error) 340 goto out; 341 342 /* 343 * pseudoflavor restrictions are not enforced on NLM, 344 * which clients virtually always use auth_sys for, 345 * even while using RPCSEC_GSS for NFS. 346 */ 347 if (access & NFSD_MAY_LOCK) 348 goto skip_pseudoflavor_check; 349 /* 350 * Clients may expect to be able to use auth_sys during mount, 351 * even if they use gss for everything else; see section 2.3.2 352 * of rfc 2623. 353 */ 354 if (access & NFSD_MAY_BYPASS_GSS_ON_ROOT 355 && exp->ex_path.dentry == dentry) 356 goto skip_pseudoflavor_check; 357 358 error = check_nfsd_access(exp, rqstp); 359 if (error) 360 goto out; 361 362 skip_pseudoflavor_check: 363 /* Finally, check access permissions. */ 364 error = nfsd_permission(rqstp, exp, dentry, access); 365 366 if (error) { 367 dprintk("fh_verify: %s/%s permission failure, " 368 "acc=%x, error=%d\n", 369 dentry->d_parent->d_name.name, 370 dentry->d_name.name, 371 access, ntohl(error)); 372 } 373 out: 374 if (error == nfserr_stale) 375 nfsdstats.fh_stale++; 376 return error; 377 } 378 379 380 /* 381 * Compose a file handle for an NFS reply. 382 * 383 * Note that when first composed, the dentry may not yet have 384 * an inode. In this case a call to fh_update should be made 385 * before the fh goes out on the wire ... 386 */ 387 static void _fh_update(struct svc_fh *fhp, struct svc_export *exp, 388 struct dentry *dentry) 389 { 390 if (dentry != exp->ex_path.dentry) { 391 struct fid *fid = (struct fid *) 392 (fhp->fh_handle.fh_auth + fhp->fh_handle.fh_size/4 - 1); 393 int maxsize = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4; 394 int subtreecheck = !(exp->ex_flags & NFSEXP_NOSUBTREECHECK); 395 396 fhp->fh_handle.fh_fileid_type = 397 exportfs_encode_fh(dentry, fid, &maxsize, subtreecheck); 398 fhp->fh_handle.fh_size += maxsize * 4; 399 } else { 400 fhp->fh_handle.fh_fileid_type = FILEID_ROOT; 401 } 402 } 403 404 /* 405 * for composing old style file handles 406 */ 407 static inline void _fh_update_old(struct dentry *dentry, 408 struct svc_export *exp, 409 struct knfsd_fh *fh) 410 { 411 fh->ofh_ino = ino_t_to_u32(dentry->d_inode->i_ino); 412 fh->ofh_generation = dentry->d_inode->i_generation; 413 if (S_ISDIR(dentry->d_inode->i_mode) || 414 (exp->ex_flags & NFSEXP_NOSUBTREECHECK)) 415 fh->ofh_dirino = 0; 416 } 417 418 static bool is_root_export(struct svc_export *exp) 419 { 420 return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root; 421 } 422 423 static struct super_block *exp_sb(struct svc_export *exp) 424 { 425 return exp->ex_path.dentry->d_inode->i_sb; 426 } 427 428 static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp) 429 { 430 switch (fsid_type) { 431 case FSID_DEV: 432 if (!old_valid_dev(exp_sb(exp)->s_dev)) 433 return 0; 434 /* FALL THROUGH */ 435 case FSID_MAJOR_MINOR: 436 case FSID_ENCODE_DEV: 437 return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV; 438 case FSID_NUM: 439 return exp->ex_flags & NFSEXP_FSID; 440 case FSID_UUID8: 441 case FSID_UUID16: 442 if (!is_root_export(exp)) 443 return 0; 444 /* fall through */ 445 case FSID_UUID4_INUM: 446 case FSID_UUID16_INUM: 447 return exp->ex_uuid != NULL; 448 } 449 return 1; 450 } 451 452 453 static void set_version_and_fsid_type(struct svc_fh *fhp, struct svc_export *exp, struct svc_fh *ref_fh) 454 { 455 u8 version; 456 u8 fsid_type; 457 retry: 458 version = 1; 459 if (ref_fh && ref_fh->fh_export == exp) { 460 version = ref_fh->fh_handle.fh_version; 461 fsid_type = ref_fh->fh_handle.fh_fsid_type; 462 463 ref_fh = NULL; 464 465 switch (version) { 466 case 0xca: 467 fsid_type = FSID_DEV; 468 break; 469 case 1: 470 break; 471 default: 472 goto retry; 473 } 474 475 /* 476 * As the fsid -> filesystem mapping was guided by 477 * user-space, there is no guarantee that the filesystem 478 * actually supports that fsid type. If it doesn't we 479 * loop around again without ref_fh set. 480 */ 481 if (!fsid_type_ok_for_exp(fsid_type, exp)) 482 goto retry; 483 } else if (exp->ex_flags & NFSEXP_FSID) { 484 fsid_type = FSID_NUM; 485 } else if (exp->ex_uuid) { 486 if (fhp->fh_maxsize >= 64) { 487 if (is_root_export(exp)) 488 fsid_type = FSID_UUID16; 489 else 490 fsid_type = FSID_UUID16_INUM; 491 } else { 492 if (is_root_export(exp)) 493 fsid_type = FSID_UUID8; 494 else 495 fsid_type = FSID_UUID4_INUM; 496 } 497 } else if (!old_valid_dev(exp_sb(exp)->s_dev)) 498 /* for newer device numbers, we must use a newer fsid format */ 499 fsid_type = FSID_ENCODE_DEV; 500 else 501 fsid_type = FSID_DEV; 502 fhp->fh_handle.fh_version = version; 503 if (version) 504 fhp->fh_handle.fh_fsid_type = fsid_type; 505 } 506 507 __be32 508 fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry, 509 struct svc_fh *ref_fh) 510 { 511 /* ref_fh is a reference file handle. 512 * if it is non-null and for the same filesystem, then we should compose 513 * a filehandle which is of the same version, where possible. 514 * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca 515 * Then create a 32byte filehandle using nfs_fhbase_old 516 * 517 */ 518 519 struct inode * inode = dentry->d_inode; 520 struct dentry *parent = dentry->d_parent; 521 __u32 *datap; 522 dev_t ex_dev = exp_sb(exp)->s_dev; 523 524 dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n", 525 MAJOR(ex_dev), MINOR(ex_dev), 526 (long) exp->ex_path.dentry->d_inode->i_ino, 527 parent->d_name.name, dentry->d_name.name, 528 (inode ? inode->i_ino : 0)); 529 530 /* Choose filehandle version and fsid type based on 531 * the reference filehandle (if it is in the same export) 532 * or the export options. 533 */ 534 set_version_and_fsid_type(fhp, exp, ref_fh); 535 536 if (ref_fh == fhp) 537 fh_put(ref_fh); 538 539 if (fhp->fh_locked || fhp->fh_dentry) { 540 printk(KERN_ERR "fh_compose: fh %s/%s not initialized!\n", 541 parent->d_name.name, dentry->d_name.name); 542 } 543 if (fhp->fh_maxsize < NFS_FHSIZE) 544 printk(KERN_ERR "fh_compose: called with maxsize %d! %s/%s\n", 545 fhp->fh_maxsize, 546 parent->d_name.name, dentry->d_name.name); 547 548 fhp->fh_dentry = dget(dentry); /* our internal copy */ 549 fhp->fh_export = exp; 550 cache_get(&exp->h); 551 552 if (fhp->fh_handle.fh_version == 0xca) { 553 /* old style filehandle please */ 554 memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE); 555 fhp->fh_handle.fh_size = NFS_FHSIZE; 556 fhp->fh_handle.ofh_dcookie = 0xfeebbaca; 557 fhp->fh_handle.ofh_dev = old_encode_dev(ex_dev); 558 fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev; 559 fhp->fh_handle.ofh_xino = 560 ino_t_to_u32(exp->ex_path.dentry->d_inode->i_ino); 561 fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry)); 562 if (inode) 563 _fh_update_old(dentry, exp, &fhp->fh_handle); 564 } else { 565 int len; 566 fhp->fh_handle.fh_auth_type = 0; 567 datap = fhp->fh_handle.fh_auth+0; 568 mk_fsid(fhp->fh_handle.fh_fsid_type, datap, ex_dev, 569 exp->ex_path.dentry->d_inode->i_ino, 570 exp->ex_fsid, exp->ex_uuid); 571 572 len = key_len(fhp->fh_handle.fh_fsid_type); 573 datap += len/4; 574 fhp->fh_handle.fh_size = 4 + len; 575 576 if (inode) 577 _fh_update(fhp, exp, dentry); 578 if (fhp->fh_handle.fh_fileid_type == 255) { 579 fh_put(fhp); 580 return nfserr_opnotsupp; 581 } 582 } 583 584 return 0; 585 } 586 587 /* 588 * Update file handle information after changing a dentry. 589 * This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create 590 */ 591 __be32 592 fh_update(struct svc_fh *fhp) 593 { 594 struct dentry *dentry; 595 596 if (!fhp->fh_dentry) 597 goto out_bad; 598 599 dentry = fhp->fh_dentry; 600 if (!dentry->d_inode) 601 goto out_negative; 602 if (fhp->fh_handle.fh_version != 1) { 603 _fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle); 604 } else { 605 if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT) 606 goto out; 607 608 _fh_update(fhp, fhp->fh_export, dentry); 609 if (fhp->fh_handle.fh_fileid_type == 255) 610 return nfserr_opnotsupp; 611 } 612 out: 613 return 0; 614 615 out_bad: 616 printk(KERN_ERR "fh_update: fh not verified!\n"); 617 goto out; 618 out_negative: 619 printk(KERN_ERR "fh_update: %s/%s still negative!\n", 620 dentry->d_parent->d_name.name, dentry->d_name.name); 621 goto out; 622 } 623 624 /* 625 * Release a file handle. 626 */ 627 void 628 fh_put(struct svc_fh *fhp) 629 { 630 struct dentry * dentry = fhp->fh_dentry; 631 struct svc_export * exp = fhp->fh_export; 632 if (dentry) { 633 fh_unlock(fhp); 634 fhp->fh_dentry = NULL; 635 dput(dentry); 636 #ifdef CONFIG_NFSD_V3 637 fhp->fh_pre_saved = 0; 638 fhp->fh_post_saved = 0; 639 #endif 640 } 641 if (exp) { 642 cache_put(&exp->h, &svc_export_cache); 643 fhp->fh_export = NULL; 644 } 645 return; 646 } 647 648 /* 649 * Shorthand for dprintk()'s 650 */ 651 char * SVCFH_fmt(struct svc_fh *fhp) 652 { 653 struct knfsd_fh *fh = &fhp->fh_handle; 654 655 static char buf[80]; 656 sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x", 657 fh->fh_size, 658 fh->fh_base.fh_pad[0], 659 fh->fh_base.fh_pad[1], 660 fh->fh_base.fh_pad[2], 661 fh->fh_base.fh_pad[3], 662 fh->fh_base.fh_pad[4], 663 fh->fh_base.fh_pad[5]); 664 return buf; 665 } 666 667 enum fsid_source fsid_source(struct svc_fh *fhp) 668 { 669 if (fhp->fh_handle.fh_version != 1) 670 return FSIDSOURCE_DEV; 671 switch(fhp->fh_handle.fh_fsid_type) { 672 case FSID_DEV: 673 case FSID_ENCODE_DEV: 674 case FSID_MAJOR_MINOR: 675 if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV) 676 return FSIDSOURCE_DEV; 677 break; 678 case FSID_NUM: 679 if (fhp->fh_export->ex_flags & NFSEXP_FSID) 680 return FSIDSOURCE_FSID; 681 break; 682 default: 683 break; 684 } 685 /* either a UUID type filehandle, or the filehandle doesn't 686 * match the export. 687 */ 688 if (fhp->fh_export->ex_flags & NFSEXP_FSID) 689 return FSIDSOURCE_FSID; 690 if (fhp->fh_export->ex_uuid) 691 return FSIDSOURCE_UUID; 692 return FSIDSOURCE_DEV; 693 } 694