1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * NFS server file handle treatment. 4 * 5 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> 6 * Portions Copyright (C) 1999 G. Allen Morris III <gam3@acm.org> 7 * Extensive rewrite by Neil Brown <neilb@cse.unsw.edu.au> Southern-Spring 1999 8 * ... and again Southern-Winter 2001 to support export_operations 9 */ 10 11 #include <linux/exportfs.h> 12 13 #include <linux/sunrpc/svcauth_gss.h> 14 #include "nfsd.h" 15 #include "vfs.h" 16 #include "auth.h" 17 #include "trace.h" 18 19 #define NFSDDBG_FACILITY NFSDDBG_FH 20 21 22 /* 23 * our acceptability function. 24 * if NOSUBTREECHECK, accept anything 25 * if not, require that we can walk up to exp->ex_dentry 26 * doing some checks on the 'x' bits 27 */ 28 static int nfsd_acceptable(void *expv, struct dentry *dentry) 29 { 30 struct svc_export *exp = expv; 31 int rv; 32 struct dentry *tdentry; 33 struct dentry *parent; 34 35 if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) 36 return 1; 37 38 tdentry = dget(dentry); 39 while (tdentry != exp->ex_path.dentry && !IS_ROOT(tdentry)) { 40 /* make sure parents give x permission to user */ 41 int err; 42 parent = dget_parent(tdentry); 43 err = inode_permission(&init_user_ns, 44 d_inode(parent), MAY_EXEC); 45 if (err < 0) { 46 dput(parent); 47 break; 48 } 49 dput(tdentry); 50 tdentry = parent; 51 } 52 if (tdentry != exp->ex_path.dentry) 53 dprintk("nfsd_acceptable failed at %p %pd\n", tdentry, tdentry); 54 rv = (tdentry == exp->ex_path.dentry); 55 dput(tdentry); 56 return rv; 57 } 58 59 /* Type check. The correct error return for type mismatches does not seem to be 60 * generally agreed upon. SunOS seems to use EISDIR if file isn't S_IFREG; a 61 * comment in the NFSv3 spec says this is incorrect (implementation notes for 62 * the write call). 63 */ 64 static inline __be32 65 nfsd_mode_check(struct svc_rqst *rqstp, struct dentry *dentry, 66 umode_t requested) 67 { 68 umode_t mode = d_inode(dentry)->i_mode & S_IFMT; 69 70 if (requested == 0) /* the caller doesn't care */ 71 return nfs_ok; 72 if (mode == requested) { 73 if (mode == S_IFDIR && !d_can_lookup(dentry)) { 74 WARN_ON_ONCE(1); 75 return nfserr_notdir; 76 } 77 return nfs_ok; 78 } 79 /* 80 * v4 has an error more specific than err_notdir which we should 81 * return in preference to err_notdir: 82 */ 83 if (rqstp->rq_vers == 4 && mode == S_IFLNK) 84 return nfserr_symlink; 85 if (requested == S_IFDIR) 86 return nfserr_notdir; 87 if (mode == S_IFDIR) 88 return nfserr_isdir; 89 return nfserr_inval; 90 } 91 92 static bool nfsd_originating_port_ok(struct svc_rqst *rqstp, int flags) 93 { 94 if (flags & NFSEXP_INSECURE_PORT) 95 return true; 96 /* We don't require gss requests to use low ports: */ 97 if (rqstp->rq_cred.cr_flavor >= RPC_AUTH_GSS) 98 return true; 99 return test_bit(RQ_SECURE, &rqstp->rq_flags); 100 } 101 102 static __be32 nfsd_setuser_and_check_port(struct svc_rqst *rqstp, 103 struct svc_export *exp) 104 { 105 int flags = nfsexp_flags(rqstp, exp); 106 107 /* Check if the request originated from a secure port. */ 108 if (!nfsd_originating_port_ok(rqstp, flags)) { 109 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]); 110 dprintk("nfsd: request from insecure port %s!\n", 111 svc_print_addr(rqstp, buf, sizeof(buf))); 112 return nfserr_perm; 113 } 114 115 /* Set user creds for this exportpoint */ 116 return nfserrno(nfsd_setuser(rqstp, exp)); 117 } 118 119 static inline __be32 check_pseudo_root(struct svc_rqst *rqstp, 120 struct dentry *dentry, struct svc_export *exp) 121 { 122 if (!(exp->ex_flags & NFSEXP_V4ROOT)) 123 return nfs_ok; 124 /* 125 * v2/v3 clients have no need for the V4ROOT export--they use 126 * the mount protocl instead; also, further V4ROOT checks may be 127 * in v4-specific code, in which case v2/v3 clients could bypass 128 * them. 129 */ 130 if (!nfsd_v4client(rqstp)) 131 return nfserr_stale; 132 /* 133 * We're exposing only the directories and symlinks that have to be 134 * traversed on the way to real exports: 135 */ 136 if (unlikely(!d_is_dir(dentry) && 137 !d_is_symlink(dentry))) 138 return nfserr_stale; 139 /* 140 * A pseudoroot export gives permission to access only one 141 * single directory; the kernel has to make another upcall 142 * before granting access to anything else under it: 143 */ 144 if (unlikely(dentry != exp->ex_path.dentry)) 145 return nfserr_stale; 146 return nfs_ok; 147 } 148 149 /* 150 * Use the given filehandle to look up the corresponding export and 151 * dentry. On success, the results are used to set fh_export and 152 * fh_dentry. 153 */ 154 static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp) 155 { 156 struct knfsd_fh *fh = &fhp->fh_handle; 157 struct fid *fid = NULL, sfid; 158 struct svc_export *exp; 159 struct dentry *dentry; 160 int fileid_type; 161 int data_left = fh->fh_size/4; 162 __be32 error; 163 164 error = nfserr_stale; 165 if (rqstp->rq_vers > 2) 166 error = nfserr_badhandle; 167 if (rqstp->rq_vers == 4 && fh->fh_size == 0) 168 return nfserr_nofilehandle; 169 170 if (fh->fh_version == 1) { 171 int len; 172 173 if (--data_left < 0) 174 return error; 175 if (fh->fh_auth_type != 0) 176 return error; 177 len = key_len(fh->fh_fsid_type) / 4; 178 if (len == 0) 179 return error; 180 if (fh->fh_fsid_type == FSID_MAJOR_MINOR) { 181 /* deprecated, convert to type 3 */ 182 len = key_len(FSID_ENCODE_DEV)/4; 183 fh->fh_fsid_type = FSID_ENCODE_DEV; 184 /* 185 * struct knfsd_fh uses host-endian fields, which are 186 * sometimes used to hold net-endian values. This 187 * confuses sparse, so we must use __force here to 188 * keep it from complaining. 189 */ 190 fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl((__force __be32)fh->fh_fsid[0]), 191 ntohl((__force __be32)fh->fh_fsid[1]))); 192 fh->fh_fsid[1] = fh->fh_fsid[2]; 193 } 194 data_left -= len; 195 if (data_left < 0) 196 return error; 197 exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_fsid); 198 fid = (struct fid *)(fh->fh_fsid + len); 199 } else { 200 __u32 tfh[2]; 201 dev_t xdev; 202 ino_t xino; 203 204 if (fh->fh_size != NFS_FHSIZE) 205 return error; 206 /* assume old filehandle format */ 207 xdev = old_decode_dev(fh->ofh_xdev); 208 xino = u32_to_ino_t(fh->ofh_xino); 209 mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL); 210 exp = rqst_exp_find(rqstp, FSID_DEV, tfh); 211 } 212 213 error = nfserr_stale; 214 if (IS_ERR(exp)) { 215 trace_nfsd_set_fh_dentry_badexport(rqstp, fhp, PTR_ERR(exp)); 216 217 if (PTR_ERR(exp) == -ENOENT) 218 return error; 219 220 return nfserrno(PTR_ERR(exp)); 221 } 222 223 if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) { 224 /* Elevate privileges so that the lack of 'r' or 'x' 225 * permission on some parent directory will 226 * not stop exportfs_decode_fh from being able 227 * to reconnect a directory into the dentry cache. 228 * The same problem can affect "SUBTREECHECK" exports, 229 * but as nfsd_acceptable depends on correct 230 * access control settings being in effect, we cannot 231 * fix that case easily. 232 */ 233 struct cred *new = prepare_creds(); 234 if (!new) { 235 error = nfserrno(-ENOMEM); 236 goto out; 237 } 238 new->cap_effective = 239 cap_raise_nfsd_set(new->cap_effective, 240 new->cap_permitted); 241 put_cred(override_creds(new)); 242 put_cred(new); 243 } else { 244 error = nfsd_setuser_and_check_port(rqstp, exp); 245 if (error) 246 goto out; 247 } 248 249 /* 250 * Look up the dentry using the NFS file handle. 251 */ 252 error = nfserr_stale; 253 if (rqstp->rq_vers > 2) 254 error = nfserr_badhandle; 255 256 if (fh->fh_version != 1) { 257 sfid.i32.ino = fh->ofh_ino; 258 sfid.i32.gen = fh->ofh_generation; 259 sfid.i32.parent_ino = fh->ofh_dirino; 260 fid = &sfid; 261 data_left = 3; 262 if (fh->ofh_dirino == 0) 263 fileid_type = FILEID_INO32_GEN; 264 else 265 fileid_type = FILEID_INO32_GEN_PARENT; 266 } else 267 fileid_type = fh->fh_fileid_type; 268 269 if (fileid_type == FILEID_ROOT) 270 dentry = dget(exp->ex_path.dentry); 271 else { 272 dentry = exportfs_decode_fh_raw(exp->ex_path.mnt, fid, 273 data_left, fileid_type, 274 nfsd_acceptable, exp); 275 if (IS_ERR_OR_NULL(dentry)) { 276 trace_nfsd_set_fh_dentry_badhandle(rqstp, fhp, 277 dentry ? PTR_ERR(dentry) : -ESTALE); 278 switch (PTR_ERR(dentry)) { 279 case -ENOMEM: 280 case -ETIMEDOUT: 281 break; 282 default: 283 dentry = ERR_PTR(-ESTALE); 284 } 285 } 286 } 287 if (dentry == NULL) 288 goto out; 289 if (IS_ERR(dentry)) { 290 if (PTR_ERR(dentry) != -EINVAL) 291 error = nfserrno(PTR_ERR(dentry)); 292 goto out; 293 } 294 295 if (d_is_dir(dentry) && 296 (dentry->d_flags & DCACHE_DISCONNECTED)) { 297 printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %pd2\n", 298 dentry); 299 } 300 301 fhp->fh_dentry = dentry; 302 fhp->fh_export = exp; 303 304 switch (rqstp->rq_vers) { 305 case 4: 306 if (dentry->d_sb->s_export_op->flags & EXPORT_OP_NOATOMIC_ATTR) 307 fhp->fh_no_atomic_attr = true; 308 break; 309 case 3: 310 if (dentry->d_sb->s_export_op->flags & EXPORT_OP_NOWCC) 311 fhp->fh_no_wcc = true; 312 break; 313 case 2: 314 fhp->fh_no_wcc = true; 315 } 316 317 return 0; 318 out: 319 exp_put(exp); 320 return error; 321 } 322 323 /** 324 * fh_verify - filehandle lookup and access checking 325 * @rqstp: pointer to current rpc request 326 * @fhp: filehandle to be verified 327 * @type: expected type of object pointed to by filehandle 328 * @access: type of access needed to object 329 * 330 * Look up a dentry from the on-the-wire filehandle, check the client's 331 * access to the export, and set the current task's credentials. 332 * 333 * Regardless of success or failure of fh_verify(), fh_put() should be 334 * called on @fhp when the caller is finished with the filehandle. 335 * 336 * fh_verify() may be called multiple times on a given filehandle, for 337 * example, when processing an NFSv4 compound. The first call will look 338 * up a dentry using the on-the-wire filehandle. Subsequent calls will 339 * skip the lookup and just perform the other checks and possibly change 340 * the current task's credentials. 341 * 342 * @type specifies the type of object expected using one of the S_IF* 343 * constants defined in include/linux/stat.h. The caller may use zero 344 * to indicate that it doesn't care, or a negative integer to indicate 345 * that it expects something not of the given type. 346 * 347 * @access is formed from the NFSD_MAY_* constants defined in 348 * fs/nfsd/vfs.h. 349 */ 350 __be32 351 fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, int access) 352 { 353 struct svc_export *exp = NULL; 354 struct dentry *dentry; 355 __be32 error; 356 357 dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp)); 358 359 if (!fhp->fh_dentry) { 360 error = nfsd_set_fh_dentry(rqstp, fhp); 361 if (error) 362 goto out; 363 } 364 dentry = fhp->fh_dentry; 365 exp = fhp->fh_export; 366 /* 367 * We still have to do all these permission checks, even when 368 * fh_dentry is already set: 369 * - fh_verify may be called multiple times with different 370 * "access" arguments (e.g. nfsd_proc_create calls 371 * fh_verify(...,NFSD_MAY_EXEC) first, then later (in 372 * nfsd_create) calls fh_verify(...,NFSD_MAY_CREATE). 373 * - in the NFSv4 case, the filehandle may have been filled 374 * in by fh_compose, and given a dentry, but further 375 * compound operations performed with that filehandle 376 * still need permissions checks. In the worst case, a 377 * mountpoint crossing may have changed the export 378 * options, and we may now need to use a different uid 379 * (for example, if different id-squashing options are in 380 * effect on the new filesystem). 381 */ 382 error = check_pseudo_root(rqstp, dentry, exp); 383 if (error) 384 goto out; 385 386 error = nfsd_setuser_and_check_port(rqstp, exp); 387 if (error) 388 goto out; 389 390 error = nfsd_mode_check(rqstp, dentry, type); 391 if (error) 392 goto out; 393 394 /* 395 * pseudoflavor restrictions are not enforced on NLM, 396 * which clients virtually always use auth_sys for, 397 * even while using RPCSEC_GSS for NFS. 398 */ 399 if (access & NFSD_MAY_LOCK || access & NFSD_MAY_BYPASS_GSS) 400 goto skip_pseudoflavor_check; 401 /* 402 * Clients may expect to be able to use auth_sys during mount, 403 * even if they use gss for everything else; see section 2.3.2 404 * of rfc 2623. 405 */ 406 if (access & NFSD_MAY_BYPASS_GSS_ON_ROOT 407 && exp->ex_path.dentry == dentry) 408 goto skip_pseudoflavor_check; 409 410 error = check_nfsd_access(exp, rqstp); 411 if (error) 412 goto out; 413 414 skip_pseudoflavor_check: 415 /* Finally, check access permissions. */ 416 error = nfsd_permission(rqstp, exp, dentry, access); 417 418 if (error) { 419 dprintk("fh_verify: %pd2 permission failure, " 420 "acc=%x, error=%d\n", 421 dentry, 422 access, ntohl(error)); 423 } 424 out: 425 if (error == nfserr_stale) 426 nfsd_stats_fh_stale_inc(exp); 427 return error; 428 } 429 430 431 /* 432 * Compose a file handle for an NFS reply. 433 * 434 * Note that when first composed, the dentry may not yet have 435 * an inode. In this case a call to fh_update should be made 436 * before the fh goes out on the wire ... 437 */ 438 static void _fh_update(struct svc_fh *fhp, struct svc_export *exp, 439 struct dentry *dentry) 440 { 441 if (dentry != exp->ex_path.dentry) { 442 struct fid *fid = (struct fid *) 443 (fhp->fh_handle.fh_fsid + fhp->fh_handle.fh_size/4 - 1); 444 int maxsize = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4; 445 int subtreecheck = !(exp->ex_flags & NFSEXP_NOSUBTREECHECK); 446 447 fhp->fh_handle.fh_fileid_type = 448 exportfs_encode_fh(dentry, fid, &maxsize, subtreecheck); 449 fhp->fh_handle.fh_size += maxsize * 4; 450 } else { 451 fhp->fh_handle.fh_fileid_type = FILEID_ROOT; 452 } 453 } 454 455 /* 456 * for composing old style file handles 457 */ 458 static inline void _fh_update_old(struct dentry *dentry, 459 struct svc_export *exp, 460 struct knfsd_fh *fh) 461 { 462 fh->ofh_ino = ino_t_to_u32(d_inode(dentry)->i_ino); 463 fh->ofh_generation = d_inode(dentry)->i_generation; 464 if (d_is_dir(dentry) || 465 (exp->ex_flags & NFSEXP_NOSUBTREECHECK)) 466 fh->ofh_dirino = 0; 467 } 468 469 static bool is_root_export(struct svc_export *exp) 470 { 471 return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root; 472 } 473 474 static struct super_block *exp_sb(struct svc_export *exp) 475 { 476 return exp->ex_path.dentry->d_sb; 477 } 478 479 static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp) 480 { 481 switch (fsid_type) { 482 case FSID_DEV: 483 if (!old_valid_dev(exp_sb(exp)->s_dev)) 484 return false; 485 fallthrough; 486 case FSID_MAJOR_MINOR: 487 case FSID_ENCODE_DEV: 488 return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV; 489 case FSID_NUM: 490 return exp->ex_flags & NFSEXP_FSID; 491 case FSID_UUID8: 492 case FSID_UUID16: 493 if (!is_root_export(exp)) 494 return false; 495 fallthrough; 496 case FSID_UUID4_INUM: 497 case FSID_UUID16_INUM: 498 return exp->ex_uuid != NULL; 499 } 500 return true; 501 } 502 503 504 static void set_version_and_fsid_type(struct svc_fh *fhp, struct svc_export *exp, struct svc_fh *ref_fh) 505 { 506 u8 version; 507 u8 fsid_type; 508 retry: 509 version = 1; 510 if (ref_fh && ref_fh->fh_export == exp) { 511 version = ref_fh->fh_handle.fh_version; 512 fsid_type = ref_fh->fh_handle.fh_fsid_type; 513 514 ref_fh = NULL; 515 516 switch (version) { 517 case 0xca: 518 fsid_type = FSID_DEV; 519 break; 520 case 1: 521 break; 522 default: 523 goto retry; 524 } 525 526 /* 527 * As the fsid -> filesystem mapping was guided by 528 * user-space, there is no guarantee that the filesystem 529 * actually supports that fsid type. If it doesn't we 530 * loop around again without ref_fh set. 531 */ 532 if (!fsid_type_ok_for_exp(fsid_type, exp)) 533 goto retry; 534 } else if (exp->ex_flags & NFSEXP_FSID) { 535 fsid_type = FSID_NUM; 536 } else if (exp->ex_uuid) { 537 if (fhp->fh_maxsize >= 64) { 538 if (is_root_export(exp)) 539 fsid_type = FSID_UUID16; 540 else 541 fsid_type = FSID_UUID16_INUM; 542 } else { 543 if (is_root_export(exp)) 544 fsid_type = FSID_UUID8; 545 else 546 fsid_type = FSID_UUID4_INUM; 547 } 548 } else if (!old_valid_dev(exp_sb(exp)->s_dev)) 549 /* for newer device numbers, we must use a newer fsid format */ 550 fsid_type = FSID_ENCODE_DEV; 551 else 552 fsid_type = FSID_DEV; 553 fhp->fh_handle.fh_version = version; 554 if (version) 555 fhp->fh_handle.fh_fsid_type = fsid_type; 556 } 557 558 __be32 559 fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry, 560 struct svc_fh *ref_fh) 561 { 562 /* ref_fh is a reference file handle. 563 * if it is non-null and for the same filesystem, then we should compose 564 * a filehandle which is of the same version, where possible. 565 * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca 566 * Then create a 32byte filehandle using nfs_fhbase_old 567 * 568 */ 569 570 struct inode * inode = d_inode(dentry); 571 dev_t ex_dev = exp_sb(exp)->s_dev; 572 573 dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %pd2, ino=%ld)\n", 574 MAJOR(ex_dev), MINOR(ex_dev), 575 (long) d_inode(exp->ex_path.dentry)->i_ino, 576 dentry, 577 (inode ? inode->i_ino : 0)); 578 579 /* Choose filehandle version and fsid type based on 580 * the reference filehandle (if it is in the same export) 581 * or the export options. 582 */ 583 set_version_and_fsid_type(fhp, exp, ref_fh); 584 585 /* If we have a ref_fh, then copy the fh_no_wcc setting from it. */ 586 fhp->fh_no_wcc = ref_fh ? ref_fh->fh_no_wcc : false; 587 588 if (ref_fh == fhp) 589 fh_put(ref_fh); 590 591 if (fhp->fh_locked || fhp->fh_dentry) { 592 printk(KERN_ERR "fh_compose: fh %pd2 not initialized!\n", 593 dentry); 594 } 595 if (fhp->fh_maxsize < NFS_FHSIZE) 596 printk(KERN_ERR "fh_compose: called with maxsize %d! %pd2\n", 597 fhp->fh_maxsize, 598 dentry); 599 600 fhp->fh_dentry = dget(dentry); /* our internal copy */ 601 fhp->fh_export = exp_get(exp); 602 603 if (fhp->fh_handle.fh_version == 0xca) { 604 /* old style filehandle please */ 605 memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE); 606 fhp->fh_handle.fh_size = NFS_FHSIZE; 607 fhp->fh_handle.ofh_dcookie = 0xfeebbaca; 608 fhp->fh_handle.ofh_dev = old_encode_dev(ex_dev); 609 fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev; 610 fhp->fh_handle.ofh_xino = 611 ino_t_to_u32(d_inode(exp->ex_path.dentry)->i_ino); 612 fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry)); 613 if (inode) 614 _fh_update_old(dentry, exp, &fhp->fh_handle); 615 } else { 616 fhp->fh_handle.fh_size = 617 key_len(fhp->fh_handle.fh_fsid_type) + 4; 618 fhp->fh_handle.fh_auth_type = 0; 619 620 mk_fsid(fhp->fh_handle.fh_fsid_type, 621 fhp->fh_handle.fh_fsid, 622 ex_dev, 623 d_inode(exp->ex_path.dentry)->i_ino, 624 exp->ex_fsid, exp->ex_uuid); 625 626 if (inode) 627 _fh_update(fhp, exp, dentry); 628 if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID) { 629 fh_put(fhp); 630 return nfserr_opnotsupp; 631 } 632 } 633 634 return 0; 635 } 636 637 /* 638 * Update file handle information after changing a dentry. 639 * This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create 640 */ 641 __be32 642 fh_update(struct svc_fh *fhp) 643 { 644 struct dentry *dentry; 645 646 if (!fhp->fh_dentry) 647 goto out_bad; 648 649 dentry = fhp->fh_dentry; 650 if (d_really_is_negative(dentry)) 651 goto out_negative; 652 if (fhp->fh_handle.fh_version != 1) { 653 _fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle); 654 } else { 655 if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT) 656 return 0; 657 658 _fh_update(fhp, fhp->fh_export, dentry); 659 if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID) 660 return nfserr_opnotsupp; 661 } 662 return 0; 663 out_bad: 664 printk(KERN_ERR "fh_update: fh not verified!\n"); 665 return nfserr_serverfault; 666 out_negative: 667 printk(KERN_ERR "fh_update: %pd2 still negative!\n", 668 dentry); 669 return nfserr_serverfault; 670 } 671 672 /* 673 * Release a file handle. 674 */ 675 void 676 fh_put(struct svc_fh *fhp) 677 { 678 struct dentry * dentry = fhp->fh_dentry; 679 struct svc_export * exp = fhp->fh_export; 680 if (dentry) { 681 fh_unlock(fhp); 682 fhp->fh_dentry = NULL; 683 dput(dentry); 684 fh_clear_wcc(fhp); 685 } 686 fh_drop_write(fhp); 687 if (exp) { 688 exp_put(exp); 689 fhp->fh_export = NULL; 690 } 691 fhp->fh_no_wcc = false; 692 return; 693 } 694 695 /* 696 * Shorthand for dprintk()'s 697 */ 698 char * SVCFH_fmt(struct svc_fh *fhp) 699 { 700 struct knfsd_fh *fh = &fhp->fh_handle; 701 702 static char buf[80]; 703 sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x", 704 fh->fh_size, 705 fh->fh_base.fh_pad[0], 706 fh->fh_base.fh_pad[1], 707 fh->fh_base.fh_pad[2], 708 fh->fh_base.fh_pad[3], 709 fh->fh_base.fh_pad[4], 710 fh->fh_base.fh_pad[5]); 711 return buf; 712 } 713 714 enum fsid_source fsid_source(const struct svc_fh *fhp) 715 { 716 if (fhp->fh_handle.fh_version != 1) 717 return FSIDSOURCE_DEV; 718 switch(fhp->fh_handle.fh_fsid_type) { 719 case FSID_DEV: 720 case FSID_ENCODE_DEV: 721 case FSID_MAJOR_MINOR: 722 if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV) 723 return FSIDSOURCE_DEV; 724 break; 725 case FSID_NUM: 726 if (fhp->fh_export->ex_flags & NFSEXP_FSID) 727 return FSIDSOURCE_FSID; 728 break; 729 default: 730 break; 731 } 732 /* either a UUID type filehandle, or the filehandle doesn't 733 * match the export. 734 */ 735 if (fhp->fh_export->ex_flags & NFSEXP_FSID) 736 return FSIDSOURCE_FSID; 737 if (fhp->fh_export->ex_uuid) 738 return FSIDSOURCE_UUID; 739 return FSIDSOURCE_DEV; 740 } 741