1 /* $NetBSD: nfs_subr.c,v 1.1.1.2 2009/03/20 20:26:49 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1997-2009 Erez Zadok 5 * Copyright (c) 1990 Jan-Simon Pendry 6 * Copyright (c) 1990 Imperial College of Science, Technology & Medicine 7 * Copyright (c) 1990 The Regents of the University of California. 8 * All rights reserved. 9 * 10 * This code is derived from software contributed to Berkeley by 11 * Jan-Simon Pendry at Imperial College, London. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. All advertising materials mentioning features or use of this software 22 * must display the following acknowledgment: 23 * This product includes software developed by the University of 24 * California, Berkeley and its contributors. 25 * 4. Neither the name of the University nor the names of its contributors 26 * may be used to endorse or promote products derived from this software 27 * without specific prior written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 32 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 39 * SUCH DAMAGE. 40 * 41 * 42 * File: am-utils/amd/nfs_subr.c 43 * 44 */ 45 46 #ifdef HAVE_CONFIG_H 47 # include <config.h> 48 #endif /* HAVE_CONFIG_H */ 49 #include <am_defs.h> 50 #include <amd.h> 51 52 /* 53 * Convert from UN*X to NFS error code. 54 * Some systems like linux define their own (see 55 * conf/mount/mount_linux.h). 56 */ 57 #ifndef nfs_error 58 # define nfs_error(e) ((nfsstat)(e)) 59 #endif /* nfs_error */ 60 61 /* 62 * File Handle structure 63 * 64 * This is interpreted by indexing the exported array 65 * by fhh_id (for old-style filehandles), or by retrieving 66 * the node name from fhh_path (for new-style filehandles). 67 * 68 * The whole structure is mapped onto a standard fhandle_t 69 * when transmitted. 70 */ 71 struct am_fh { 72 u_int fhh_gen; /* generation number */ 73 union { 74 struct { 75 int fhh_type; /* old or new am_fh */ 76 pid_t fhh_pid; /* process id */ 77 int fhh_id; /* map id */ 78 } s; 79 char fhh_path[NFS_FHSIZE-sizeof(u_int)]; /* path to am_node */ 80 } u; 81 }; 82 83 84 /* forward declarations */ 85 /* converting am-filehandles to mount-points */ 86 static am_node *fh_to_mp3(am_nfs_fh *fhp, int *rp, int vop); 87 static am_node *fh_to_mp(am_nfs_fh *fhp); 88 static void count_map_entries(const am_node *mp, u_int *out_blocks, u_int *out_bfree, u_int *out_bavail); 89 90 91 static char * 92 do_readlink(am_node *mp, int *error_return) 93 { 94 char *ln; 95 96 /* 97 * If there is a readlink method then use it, 98 * otherwise if a link exists use that, 99 * otherwise use the mount point. 100 */ 101 if (mp->am_mnt->mf_ops->readlink) { 102 int retry = 0; 103 mp = (*mp->am_mnt->mf_ops->readlink) (mp, &retry); 104 if (mp == NULL) { 105 *error_return = retry; 106 return 0; 107 } 108 /* reschedule_timeout_mp(); */ 109 } 110 111 if (mp->am_link) { 112 ln = mp->am_link; 113 } else { 114 ln = mp->am_mnt->mf_mount; 115 } 116 117 return ln; 118 } 119 120 121 voidp 122 nfsproc_null_2_svc(voidp argp, struct svc_req *rqstp) 123 { 124 static char res; 125 126 return (voidp) &res; 127 } 128 129 130 nfsattrstat * 131 nfsproc_getattr_2_svc(am_nfs_fh *argp, struct svc_req *rqstp) 132 { 133 static nfsattrstat res; 134 am_node *mp; 135 int retry = 0; 136 time_t now = clocktime(NULL); 137 138 if (amuDebug(D_TRACE)) 139 plog(XLOG_DEBUG, "getattr:"); 140 141 mp = fh_to_mp3(argp, &retry, VLOOK_CREATE); 142 if (mp == NULL) { 143 if (amuDebug(D_TRACE)) 144 plog(XLOG_DEBUG, "\tretry=%d", retry); 145 146 if (retry < 0) { 147 amd_stats.d_drops++; 148 return 0; 149 } 150 res.ns_status = nfs_error(retry); 151 return &res; 152 } 153 154 res = mp->am_attr; 155 if (amuDebug(D_TRACE)) 156 plog(XLOG_DEBUG, "\tstat(%s), size = %d, mtime=%ld.%ld", 157 mp->am_path, 158 (int) res.ns_u.ns_attr_u.na_size, 159 (long) res.ns_u.ns_attr_u.na_mtime.nt_seconds, 160 (long) res.ns_u.ns_attr_u.na_mtime.nt_useconds); 161 162 /* Delay unmount of what was looked up */ 163 if (mp->am_timeo_w < 4 * gopt.am_timeo_w) 164 mp->am_timeo_w += gopt.am_timeo_w; 165 mp->am_ttl = now + mp->am_timeo_w; 166 167 mp->am_stats.s_getattr++; 168 return &res; 169 } 170 171 172 nfsattrstat * 173 nfsproc_setattr_2_svc(nfssattrargs *argp, struct svc_req *rqstp) 174 { 175 static nfsattrstat res; 176 177 if (!fh_to_mp(&argp->sag_fhandle)) 178 res.ns_status = nfs_error(ESTALE); 179 else 180 res.ns_status = nfs_error(EROFS); 181 182 return &res; 183 } 184 185 186 voidp 187 nfsproc_root_2_svc(voidp argp, struct svc_req *rqstp) 188 { 189 static char res; 190 191 return (voidp) &res; 192 } 193 194 195 nfsdiropres * 196 nfsproc_lookup_2_svc(nfsdiropargs *argp, struct svc_req *rqstp) 197 { 198 static nfsdiropres res; 199 am_node *mp; 200 int retry; 201 uid_t uid; 202 gid_t gid; 203 204 if (amuDebug(D_TRACE)) 205 plog(XLOG_DEBUG, "lookup:"); 206 207 /* finally, find the effective uid/gid from RPC request */ 208 if (getcreds(rqstp, &uid, &gid, nfsxprt) < 0) 209 plog(XLOG_ERROR, "cannot get uid/gid from RPC credentials"); 210 xsnprintf(opt_uid, sizeof(uid_str), "%d", (int) uid); 211 xsnprintf(opt_gid, sizeof(gid_str), "%d", (int) gid); 212 213 mp = fh_to_mp3(&argp->da_fhandle, &retry, VLOOK_CREATE); 214 if (mp == NULL) { 215 if (retry < 0) { 216 amd_stats.d_drops++; 217 return 0; 218 } 219 res.dr_status = nfs_error(retry); 220 } else { 221 int error; 222 am_node *ap; 223 if (amuDebug(D_TRACE)) 224 plog(XLOG_DEBUG, "\tlookup(%s, %s)", mp->am_path, argp->da_name); 225 ap = mp->am_mnt->mf_ops->lookup_child(mp, argp->da_name, &error, VLOOK_CREATE); 226 if (ap && error < 0) 227 ap = mp->am_mnt->mf_ops->mount_child(ap, &error); 228 if (ap == 0) { 229 if (error < 0) { 230 amd_stats.d_drops++; 231 return 0; 232 } 233 res.dr_status = nfs_error(error); 234 } else { 235 /* 236 * XXX: EXPERIMENTAL! Delay unmount of what was looked up. This 237 * should reduce the chance for race condition between unmounting an 238 * entry synchronously, and re-mounting it asynchronously. 239 */ 240 if (ap->am_ttl < mp->am_ttl) 241 ap->am_ttl = mp->am_ttl; 242 mp_to_fh(ap, &res.dr_u.dr_drok_u.drok_fhandle); 243 res.dr_u.dr_drok_u.drok_attributes = ap->am_fattr; 244 res.dr_status = NFS_OK; 245 } 246 mp->am_stats.s_lookup++; 247 /* reschedule_timeout_mp(); */ 248 } 249 250 return &res; 251 } 252 253 254 void 255 nfs_quick_reply(am_node *mp, int error) 256 { 257 SVCXPRT *transp = mp->am_transp; 258 nfsdiropres res; 259 xdrproc_t xdr_result = (xdrproc_t) xdr_diropres; 260 261 /* 262 * If there's a transp structure then we can reply to the client's 263 * nfs lookup request. 264 */ 265 if (transp) { 266 if (error == 0) { 267 /* 268 * Construct a valid reply to a lookup request. Same 269 * code as in nfsproc_lookup_2_svc() above. 270 */ 271 mp_to_fh(mp, &res.dr_u.dr_drok_u.drok_fhandle); 272 res.dr_u.dr_drok_u.drok_attributes = mp->am_fattr; 273 res.dr_status = NFS_OK; 274 } else 275 /* 276 * Return the error that was passed to us. 277 */ 278 res.dr_status = nfs_error(error); 279 280 /* 281 * Send off our reply 282 */ 283 if (!svc_sendreply(transp, (XDRPROC_T_TYPE) xdr_result, (SVC_IN_ARG_TYPE) & res)) 284 svcerr_systemerr(transp); 285 286 /* 287 * Free up transp. It's only used for one reply. 288 */ 289 XFREE(mp->am_transp); 290 dlog("Quick reply sent for %s", mp->am_mnt->mf_mount); 291 } 292 } 293 294 295 nfsreadlinkres * 296 nfsproc_readlink_2_svc(am_nfs_fh *argp, struct svc_req *rqstp) 297 { 298 static nfsreadlinkres res; 299 am_node *mp; 300 int retry; 301 302 if (amuDebug(D_TRACE)) 303 plog(XLOG_DEBUG, "readlink:"); 304 305 mp = fh_to_mp3(argp, &retry, VLOOK_CREATE); 306 if (mp == NULL) { 307 readlink_retry: 308 if (retry < 0) { 309 amd_stats.d_drops++; 310 return 0; 311 } 312 res.rlr_status = nfs_error(retry); 313 } else { 314 char *ln = do_readlink(mp, &retry); 315 if (ln == 0) 316 goto readlink_retry; 317 res.rlr_status = NFS_OK; 318 if (amuDebug(D_TRACE) && ln) 319 plog(XLOG_DEBUG, "\treadlink(%s) = %s", mp->am_path, ln); 320 res.rlr_u.rlr_data_u = ln; 321 mp->am_stats.s_readlink++; 322 } 323 324 return &res; 325 } 326 327 328 nfsreadres * 329 nfsproc_read_2_svc(nfsreadargs *argp, struct svc_req *rqstp) 330 { 331 static nfsreadres res; 332 333 memset((char *) &res, 0, sizeof(res)); 334 res.rr_status = nfs_error(EACCES); 335 336 return &res; 337 } 338 339 340 voidp 341 nfsproc_writecache_2_svc(voidp argp, struct svc_req *rqstp) 342 { 343 static char res; 344 345 return (voidp) &res; 346 } 347 348 349 nfsattrstat * 350 nfsproc_write_2_svc(nfswriteargs *argp, struct svc_req *rqstp) 351 { 352 static nfsattrstat res; 353 354 if (!fh_to_mp(&argp->wra_fhandle)) 355 res.ns_status = nfs_error(ESTALE); 356 else 357 res.ns_status = nfs_error(EROFS); 358 359 return &res; 360 } 361 362 363 nfsdiropres * 364 nfsproc_create_2_svc(nfscreateargs *argp, struct svc_req *rqstp) 365 { 366 static nfsdiropres res; 367 368 if (!fh_to_mp(&argp->ca_where.da_fhandle)) 369 res.dr_status = nfs_error(ESTALE); 370 else 371 res.dr_status = nfs_error(EROFS); 372 373 return &res; 374 } 375 376 377 static nfsstat * 378 unlink_or_rmdir(nfsdiropargs *argp, struct svc_req *rqstp, int unlinkp) 379 { 380 static nfsstat res; 381 int retry; 382 383 am_node *mp = fh_to_mp3(&argp->da_fhandle, &retry, VLOOK_DELETE); 384 if (mp == NULL) { 385 if (retry < 0) { 386 amd_stats.d_drops++; 387 return 0; 388 } 389 res = nfs_error(retry); 390 goto out; 391 } 392 393 if (mp->am_fattr.na_type != NFDIR) { 394 res = nfs_error(ENOTDIR); 395 goto out; 396 } 397 398 if (amuDebug(D_TRACE)) 399 plog(XLOG_DEBUG, "\tremove(%s, %s)", mp->am_path, argp->da_name); 400 401 mp = mp->am_mnt->mf_ops->lookup_child(mp, argp->da_name, &retry, VLOOK_DELETE); 402 if (mp == NULL) { 403 /* 404 * Ignore retries... 405 */ 406 if (retry < 0) 407 retry = 0; 408 /* 409 * Usual NFS workaround... 410 */ 411 else if (retry == ENOENT) 412 retry = 0; 413 res = nfs_error(retry); 414 } else { 415 forcibly_timeout_mp(mp); 416 res = NFS_OK; 417 } 418 419 out: 420 return &res; 421 } 422 423 424 nfsstat * 425 nfsproc_remove_2_svc(nfsdiropargs *argp, struct svc_req *rqstp) 426 { 427 return unlink_or_rmdir(argp, rqstp, TRUE); 428 } 429 430 431 nfsstat * 432 nfsproc_rename_2_svc(nfsrenameargs *argp, struct svc_req *rqstp) 433 { 434 static nfsstat res; 435 436 if (!fh_to_mp(&argp->rna_from.da_fhandle) || !fh_to_mp(&argp->rna_to.da_fhandle)) 437 res = nfs_error(ESTALE); 438 /* 439 * If the kernel is doing clever things with referenced files 440 * then let it pretend... 441 */ 442 else if (NSTREQ(argp->rna_to.da_name, ".nfs", 4)) 443 res = NFS_OK; 444 /* 445 * otherwise a failure 446 */ 447 else 448 res = nfs_error(EROFS); 449 450 return &res; 451 } 452 453 454 nfsstat * 455 nfsproc_link_2_svc(nfslinkargs *argp, struct svc_req *rqstp) 456 { 457 static nfsstat res; 458 459 if (!fh_to_mp(&argp->la_fhandle) || !fh_to_mp(&argp->la_to.da_fhandle)) 460 res = nfs_error(ESTALE); 461 else 462 res = nfs_error(EROFS); 463 464 return &res; 465 } 466 467 468 nfsstat * 469 nfsproc_symlink_2_svc(nfssymlinkargs *argp, struct svc_req *rqstp) 470 { 471 static nfsstat res; 472 473 if (!fh_to_mp(&argp->sla_from.da_fhandle)) 474 res = nfs_error(ESTALE); 475 else 476 res = nfs_error(EROFS); 477 478 return &res; 479 } 480 481 482 nfsdiropres * 483 nfsproc_mkdir_2_svc(nfscreateargs *argp, struct svc_req *rqstp) 484 { 485 static nfsdiropres res; 486 487 if (!fh_to_mp(&argp->ca_where.da_fhandle)) 488 res.dr_status = nfs_error(ESTALE); 489 else 490 res.dr_status = nfs_error(EROFS); 491 492 return &res; 493 } 494 495 496 nfsstat * 497 nfsproc_rmdir_2_svc(nfsdiropargs *argp, struct svc_req *rqstp) 498 { 499 return unlink_or_rmdir(argp, rqstp, FALSE); 500 } 501 502 503 nfsreaddirres * 504 nfsproc_readdir_2_svc(nfsreaddirargs *argp, struct svc_req *rqstp) 505 { 506 static nfsreaddirres res; 507 static nfsentry e_res[MAX_READDIR_ENTRIES]; 508 am_node *mp; 509 int retry; 510 511 if (amuDebug(D_TRACE)) 512 plog(XLOG_DEBUG, "readdir:"); 513 514 mp = fh_to_mp3(&argp->rda_fhandle, &retry, VLOOK_CREATE); 515 if (mp == NULL) { 516 if (retry < 0) { 517 amd_stats.d_drops++; 518 return 0; 519 } 520 res.rdr_status = nfs_error(retry); 521 } else { 522 if (amuDebug(D_TRACE)) 523 plog(XLOG_DEBUG, "\treaddir(%s)", mp->am_path); 524 res.rdr_status = nfs_error((*mp->am_mnt->mf_ops->readdir) 525 (mp, argp->rda_cookie, 526 &res.rdr_u.rdr_reply_u, e_res, argp->rda_count)); 527 mp->am_stats.s_readdir++; 528 } 529 530 return &res; 531 } 532 533 534 nfsstatfsres * 535 nfsproc_statfs_2_svc(am_nfs_fh *argp, struct svc_req *rqstp) 536 { 537 static nfsstatfsres res; 538 am_node *mp; 539 int retry; 540 mntent_t mnt; 541 542 if (amuDebug(D_TRACE)) 543 plog(XLOG_DEBUG, "statfs:"); 544 545 mp = fh_to_mp3(argp, &retry, VLOOK_CREATE); 546 if (mp == NULL) { 547 if (retry < 0) { 548 amd_stats.d_drops++; 549 return 0; 550 } 551 res.sfr_status = nfs_error(retry); 552 } else { 553 nfsstatfsokres *fp; 554 if (amuDebug(D_TRACE)) 555 plog(XLOG_DEBUG, "\tstat_fs(%s)", mp->am_path); 556 557 /* 558 * just return faked up file system information 559 */ 560 fp = &res.sfr_u.sfr_reply_u; 561 562 fp->sfrok_tsize = 1024; 563 fp->sfrok_bsize = 1024; 564 565 /* check if map is browsable and show_statfs_entries=yes */ 566 if ((gopt.flags & CFM_SHOW_STATFS_ENTRIES) && 567 mp->am_mnt && mp->am_mnt->mf_mopts) { 568 mnt.mnt_opts = mp->am_mnt->mf_mopts; 569 if (amu_hasmntopt(&mnt, "browsable")) { 570 count_map_entries(mp, 571 &fp->sfrok_blocks, 572 &fp->sfrok_bfree, 573 &fp->sfrok_bavail); 574 } 575 } else { 576 fp->sfrok_blocks = 0; /* set to 1 if you don't want empty automounts */ 577 fp->sfrok_bfree = 0; 578 fp->sfrok_bavail = 0; 579 } 580 581 res.sfr_status = NFS_OK; 582 mp->am_stats.s_statfs++; 583 } 584 585 return &res; 586 } 587 588 589 /* 590 * count how many total entries there are in a map, and how many 591 * of them are in use. 592 */ 593 static void 594 count_map_entries(const am_node *mp, u_int *out_blocks, u_int *out_bfree, u_int *out_bavail) 595 { 596 u_int blocks, bfree, bavail, i; 597 mntfs *mf; 598 mnt_map *mmp; 599 kv *k; 600 601 blocks = bfree = bavail = 0; 602 if (!mp) 603 goto out; 604 mf = mp->am_mnt; 605 if (!mf) 606 goto out; 607 mmp = (mnt_map *) mf->mf_private; 608 if (!mmp) 609 goto out; 610 611 /* iterate over keys */ 612 for (i = 0; i < NKVHASH; i++) { 613 for (k = mmp->kvhash[i]; k ; k = k->next) { 614 if (!k->key) 615 continue; 616 blocks++; 617 /* 618 * XXX: Need to count how many are actively in use and recompute 619 * bfree and bavail based on it. 620 */ 621 } 622 } 623 624 out: 625 *out_blocks = blocks; 626 *out_bfree = bfree; 627 *out_bavail = bavail; 628 } 629 630 631 /* 632 * Convert from file handle to automount node. 633 */ 634 static am_node * 635 fh_to_mp3(am_nfs_fh *fhp, int *rp, int vop) 636 { 637 struct am_fh *fp = (struct am_fh *) fhp; 638 am_node *ap = NULL; 639 640 if (fp->u.s.fhh_type != 0) { 641 /* New filehandle type */ 642 int len = sizeof(*fhp) - sizeof(fp->fhh_gen); 643 char *path = xmalloc(len+1); 644 /* 645 * Because fhp is treated as a filehandle we use memcpy 646 * instead of xstrlcpy. 647 */ 648 memcpy(path, (char *) fp->u.fhh_path, len); 649 path[len] = '\0'; 650 /* dlog("fh_to_mp3: new filehandle: %s", path); */ 651 652 ap = path_to_exported_ap(path); 653 XFREE(path); 654 } else { 655 /* dlog("fh_to_mp3: old filehandle: %d", fp->u.s.fhh_id); */ 656 /* 657 * Check process id matches 658 * If it doesn't then it is probably 659 * from an old kernel-cached filehandle 660 * which is now out of date. 661 */ 662 if (fp->u.s.fhh_pid != get_server_pid()) { 663 dlog("fh_to_mp3: wrong pid %ld != my pid %ld", 664 (long) fp->u.s.fhh_pid, get_server_pid()); 665 goto drop; 666 } 667 668 /* 669 * Get hold of the supposed mount node 670 */ 671 ap = get_exported_ap(fp->u.s.fhh_id); 672 } 673 674 /* 675 * Check the generation number in the node 676 * matches the one from the kernel. If not 677 * then the old node has been timed out and 678 * a new one allocated. 679 */ 680 if (ap != NULL && ap->am_gen != fp->fhh_gen) 681 ap = NULL; 682 683 /* 684 * If it doesn't exists then drop the request 685 */ 686 if (!ap) 687 goto drop; 688 689 #if 0 690 /* 691 * If the node is hung then locate a new node 692 * for it. This implements the replicated filesystem 693 * retries. 694 */ 695 if (ap->am_mnt && FSRV_ISDOWN(ap->am_mnt->mf_server) && ap->am_parent) { 696 int error; 697 am_node *orig_ap = ap; 698 699 dlog("fh_to_mp3: %s (%s) is hung: lookup alternative file server", 700 orig_ap->am_path, orig_ap->am_mnt->mf_info); 701 702 /* 703 * Update modify time of parent node. 704 * With any luck the kernel will re-stat 705 * the child node and get new information. 706 */ 707 clocktime(&orig_ap->am_fattr.na_mtime); 708 709 /* 710 * Call the parent's lookup routine for an object 711 * with the same name. This may return -1 in error 712 * if a mount is in progress. In any case, if no 713 * mount node is returned the error code is propagated 714 * to the caller. 715 */ 716 if (vop == VLOOK_CREATE) { 717 ap = orig_ap->am_parent->am_mnt->mf_ops->lookup_child(orig_ap->am_parent, orig_ap->am_name, &error, vop); 718 if (ap && error < 0) 719 ap = orig_ap->am_parent->am_mnt->mf_ops->mount_child(ap, &error); 720 } else { 721 ap = NULL; 722 error = ESTALE; 723 } 724 if (ap == 0) { 725 if (error < 0 && amd_state == Finishing) 726 error = ENOENT; 727 *rp = error; 728 return 0; 729 } 730 731 /* 732 * Update last access to original node. This 733 * avoids timing it out and so sending ESTALE 734 * back to the kernel. 735 * XXX - Not sure we need this anymore (jsp, 90/10/6). 736 */ 737 new_ttl(orig_ap); 738 739 } 740 #endif /* 0 */ 741 742 /* 743 * Disallow references to objects being unmounted, unless 744 * they are automount points. 745 */ 746 if (ap->am_mnt && (ap->am_mnt->mf_flags & MFF_UNMOUNTING) && 747 !(ap->am_flags & AMF_ROOT)) { 748 if (amd_state == Finishing) 749 *rp = ENOENT; 750 else 751 *rp = -1; 752 return 0; 753 } 754 new_ttl(ap); 755 756 drop: 757 if (!ap || !ap->am_mnt) { 758 /* 759 * If we are shutting down then it is likely 760 * that this node has disappeared because of 761 * a fast timeout. To avoid things thrashing 762 * just pretend it doesn't exist at all. If 763 * ESTALE is returned, some NFS clients just 764 * keep retrying (stupid or what - if it's 765 * stale now, what's it going to be in 5 minutes?) 766 */ 767 if (amd_state == Finishing) 768 *rp = ENOENT; 769 else { 770 *rp = ESTALE; 771 amd_stats.d_stale++; 772 } 773 } 774 775 return ap; 776 } 777 778 779 static am_node * 780 fh_to_mp(am_nfs_fh *fhp) 781 { 782 int dummy; 783 784 return fh_to_mp3(fhp, &dummy, VLOOK_CREATE); 785 } 786 787 788 /* 789 * Convert from automount node to file handle. 790 */ 791 void 792 mp_to_fh(am_node *mp, am_nfs_fh *fhp) 793 { 794 u_int pathlen; 795 struct am_fh *fp = (struct am_fh *) fhp; 796 797 memset((char *) fhp, 0, sizeof(am_nfs_fh)); 798 799 /* Store the generation number */ 800 fp->fhh_gen = mp->am_gen; 801 802 pathlen = strlen(mp->am_path); 803 if (pathlen <= sizeof(*fhp) - sizeof(fp->fhh_gen)) { 804 /* dlog("mp_to_fh: new filehandle: %s", mp->am_path); */ 805 806 /* 807 * Because fhp is treated as a filehandle we use memcpy instead of 808 * xstrlcpy. 809 */ 810 memcpy(fp->u.fhh_path, mp->am_path, pathlen); /* making a filehandle */ 811 } else { 812 /* 813 * Take the process id 814 */ 815 fp->u.s.fhh_pid = get_server_pid(); 816 817 /* 818 * ... the map number 819 */ 820 fp->u.s.fhh_id = mp->am_mapno; 821 822 /* 823 * ... and the generation number (previously stored) 824 * to make a "unique" triple that will never 825 * be reallocated except across reboots (which doesn't matter) 826 * or if we are unlucky enough to be given the same 827 * pid as a previous amd (very unlikely). 828 */ 829 /* dlog("mp_to_fh: old filehandle: %d", fp->u.s.fhh_id); */ 830 } 831 } 832