zfs_dir.c revision 290765
1/* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21/* 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2013, 2015 by Delphix. All rights reserved. 24 */ 25 26#include <sys/types.h> 27#include <sys/param.h> 28#include <sys/time.h> 29#include <sys/systm.h> 30#include <sys/sysmacros.h> 31#include <sys/resource.h> 32#include <sys/vfs.h> 33#include <sys/vnode.h> 34#include <sys/file.h> 35#include <sys/kmem.h> 36#include <sys/uio.h> 37#include <sys/cmn_err.h> 38#include <sys/errno.h> 39#include <sys/stat.h> 40#include <sys/unistd.h> 41#include <sys/sunddi.h> 42#include <sys/random.h> 43#include <sys/policy.h> 44#include <sys/kcondvar.h> 45#include <sys/callb.h> 46#include <sys/smp.h> 47#include <sys/zfs_dir.h> 48#include <sys/zfs_acl.h> 49#include <sys/fs/zfs.h> 50#include <sys/zap.h> 51#include <sys/dmu.h> 52#include <sys/atomic.h> 53#include <sys/zfs_ctldir.h> 54#include <sys/zfs_fuid.h> 55#include <sys/sa.h> 56#include <sys/zfs_sa.h> 57#include <sys/dnlc.h> 58#include <sys/extdirent.h> 59 60/* 61 * zfs_match_find() is used by zfs_dirent_lock() to peform zap lookups 62 * of names after deciding which is the appropriate lookup interface. 63 */ 64static int 65zfs_match_find(zfsvfs_t *zfsvfs, znode_t *dzp, char *name, boolean_t exact, 66 boolean_t update, int *deflags, pathname_t *rpnp, uint64_t *zoid) 67{ 68 int error; 69 70 if (zfsvfs->z_norm) { 71 matchtype_t mt = MT_FIRST; 72 boolean_t conflict = B_FALSE; 73 size_t bufsz = 0; 74 char *buf = NULL; 75 76 if (rpnp) { 77 buf = rpnp->pn_buf; 78 bufsz = rpnp->pn_bufsize; 79 } 80 if (exact) 81 mt = MT_EXACT; 82 /* 83 * In the non-mixed case we only expect there would ever 84 * be one match, but we need to use the normalizing lookup. 85 */ 86 error = zap_lookup_norm(zfsvfs->z_os, dzp->z_id, name, 8, 1, 87 zoid, mt, buf, bufsz, &conflict); 88 if (!error && deflags) 89 *deflags = conflict ? ED_CASE_CONFLICT : 0; 90 } else { 91 error = zap_lookup(zfsvfs->z_os, dzp->z_id, name, 8, 1, zoid); 92 } 93 *zoid = ZFS_DIRENT_OBJ(*zoid); 94 95 if (error == ENOENT && update) 96 dnlc_update(ZTOV(dzp), name, DNLC_NO_VNODE); 97 98 return (error); 99} 100 101/* 102 * Lock a directory entry. A dirlock on <dzp, name> protects that name 103 * in dzp's directory zap object. As long as you hold a dirlock, you can 104 * assume two things: (1) dzp cannot be reaped, and (2) no other thread 105 * can change the zap entry for (i.e. link or unlink) this name. 106 * 107 * Input arguments: 108 * dzp - znode for directory 109 * name - name of entry to lock 110 * flag - ZNEW: if the entry already exists, fail with EEXIST. 111 * ZEXISTS: if the entry does not exist, fail with ENOENT. 112 * ZSHARED: allow concurrent access with other ZSHARED callers. 113 * ZXATTR: we want dzp's xattr directory 114 * ZCILOOK: On a mixed sensitivity file system, 115 * this lookup should be case-insensitive. 116 * ZCIEXACT: On a purely case-insensitive file system, 117 * this lookup should be case-sensitive. 118 * ZRENAMING: we are locking for renaming, force narrow locks 119 * ZHAVELOCK: Don't grab the z_name_lock for this call. The 120 * current thread already holds it. 121 * 122 * Output arguments: 123 * zpp - pointer to the znode for the entry (NULL if there isn't one) 124 * dlpp - pointer to the dirlock for this entry (NULL on error) 125 * direntflags - (case-insensitive lookup only) 126 * flags if multiple case-sensitive matches exist in directory 127 * realpnp - (case-insensitive lookup only) 128 * actual name matched within the directory 129 * 130 * Return value: 0 on success or errno on failure. 131 * 132 * NOTE: Always checks for, and rejects, '.' and '..'. 133 * NOTE: For case-insensitive file systems we take wide locks (see below), 134 * but return znode pointers to a single match. 135 */ 136int 137zfs_dirent_lock(zfs_dirlock_t **dlpp, znode_t *dzp, char *name, znode_t **zpp, 138 int flag, int *direntflags, pathname_t *realpnp) 139{ 140 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 141 zfs_dirlock_t *dl; 142 boolean_t update; 143 boolean_t exact; 144 uint64_t zoid; 145 vnode_t *vp = NULL; 146 int error = 0; 147 int cmpflags; 148 149 *zpp = NULL; 150 *dlpp = NULL; 151 152 /* 153 * Verify that we are not trying to lock '.', '..', or '.zfs' 154 */ 155 if (name[0] == '.' && 156 (name[1] == '\0' || (name[1] == '.' && name[2] == '\0')) || 157 zfs_has_ctldir(dzp) && strcmp(name, ZFS_CTLDIR_NAME) == 0) 158 return (SET_ERROR(EEXIST)); 159 160 /* 161 * Case sensitivity and normalization preferences are set when 162 * the file system is created. These are stored in the 163 * zfsvfs->z_case and zfsvfs->z_norm fields. These choices 164 * affect what vnodes can be cached in the DNLC, how we 165 * perform zap lookups, and the "width" of our dirlocks. 166 * 167 * A normal dirlock locks a single name. Note that with 168 * normalization a name can be composed multiple ways, but 169 * when normalized, these names all compare equal. A wide 170 * dirlock locks multiple names. We need these when the file 171 * system is supporting mixed-mode access. It is sometimes 172 * necessary to lock all case permutations of file name at 173 * once so that simultaneous case-insensitive/case-sensitive 174 * behaves as rationally as possible. 175 */ 176 177 /* 178 * Decide if exact matches should be requested when performing 179 * a zap lookup on file systems supporting case-insensitive 180 * access. 181 */ 182 exact = 183 ((zfsvfs->z_case == ZFS_CASE_INSENSITIVE) && (flag & ZCIEXACT)) || 184 ((zfsvfs->z_case == ZFS_CASE_MIXED) && !(flag & ZCILOOK)); 185 186 /* 187 * Only look in or update the DNLC if we are looking for the 188 * name on a file system that does not require normalization 189 * or case folding. We can also look there if we happen to be 190 * on a non-normalizing, mixed sensitivity file system IF we 191 * are looking for the exact name. 192 * 193 * Maybe can add TO-UPPERed version of name to dnlc in ci-only 194 * case for performance improvement? 195 */ 196 update = !zfsvfs->z_norm || 197 ((zfsvfs->z_case == ZFS_CASE_MIXED) && 198 !(zfsvfs->z_norm & ~U8_TEXTPREP_TOUPPER) && !(flag & ZCILOOK)); 199 200 /* 201 * ZRENAMING indicates we are in a situation where we should 202 * take narrow locks regardless of the file system's 203 * preferences for normalizing and case folding. This will 204 * prevent us deadlocking trying to grab the same wide lock 205 * twice if the two names happen to be case-insensitive 206 * matches. 207 */ 208 if (flag & ZRENAMING) 209 cmpflags = 0; 210 else 211 cmpflags = zfsvfs->z_norm; 212 213 /* 214 * Wait until there are no locks on this name. 215 * 216 * Don't grab the the lock if it is already held. However, cannot 217 * have both ZSHARED and ZHAVELOCK together. 218 */ 219 ASSERT(!(flag & ZSHARED) || !(flag & ZHAVELOCK)); 220 if (!(flag & ZHAVELOCK)) 221 rw_enter(&dzp->z_name_lock, RW_READER); 222 223 mutex_enter(&dzp->z_lock); 224 for (;;) { 225 if (dzp->z_unlinked) { 226 mutex_exit(&dzp->z_lock); 227 if (!(flag & ZHAVELOCK)) 228 rw_exit(&dzp->z_name_lock); 229 return (SET_ERROR(ENOENT)); 230 } 231 for (dl = dzp->z_dirlocks; dl != NULL; dl = dl->dl_next) { 232 if ((u8_strcmp(name, dl->dl_name, 0, cmpflags, 233 U8_UNICODE_LATEST, &error) == 0) || error != 0) 234 break; 235 } 236 if (error != 0) { 237 mutex_exit(&dzp->z_lock); 238 if (!(flag & ZHAVELOCK)) 239 rw_exit(&dzp->z_name_lock); 240 return (SET_ERROR(ENOENT)); 241 } 242 if (dl == NULL) { 243 size_t namesize; 244 245 /* 246 * Allocate a new dirlock and add it to the list. 247 */ 248 namesize = strlen(name) + 1; 249 dl = kmem_alloc(sizeof (zfs_dirlock_t) + namesize, 250 KM_SLEEP); 251 cv_init(&dl->dl_cv, NULL, CV_DEFAULT, NULL); 252 dl->dl_name = (char *)(dl + 1); 253 bcopy(name, dl->dl_name, namesize); 254 dl->dl_sharecnt = 0; 255 dl->dl_namelock = 0; 256 dl->dl_namesize = namesize; 257 dl->dl_dzp = dzp; 258 dl->dl_next = dzp->z_dirlocks; 259 dzp->z_dirlocks = dl; 260 break; 261 } 262 if ((flag & ZSHARED) && dl->dl_sharecnt != 0) 263 break; 264 cv_wait(&dl->dl_cv, &dzp->z_lock); 265 } 266 267 /* 268 * If the z_name_lock was NOT held for this dirlock record it. 269 */ 270 if (flag & ZHAVELOCK) 271 dl->dl_namelock = 1; 272 273 if (flag & ZSHARED) 274 dl->dl_sharecnt++; 275 276 mutex_exit(&dzp->z_lock); 277 278 /* 279 * We have a dirlock on the name. (Note that it is the dirlock, 280 * not the dzp's z_lock, that protects the name in the zap object.) 281 * See if there's an object by this name; if so, put a hold on it. 282 */ 283 if (flag & ZXATTR) { 284 error = sa_lookup(dzp->z_sa_hdl, SA_ZPL_XATTR(zfsvfs), &zoid, 285 sizeof (zoid)); 286 if (error == 0) 287 error = (zoid == 0 ? ENOENT : 0); 288 } else { 289 if (update) 290 vp = dnlc_lookup(ZTOV(dzp), name); 291 if (vp == DNLC_NO_VNODE) { 292 VN_RELE(vp); 293 error = SET_ERROR(ENOENT); 294 } else if (vp) { 295 if (flag & ZNEW) { 296 zfs_dirent_unlock(dl); 297 VN_RELE(vp); 298 return (SET_ERROR(EEXIST)); 299 } 300 *dlpp = dl; 301 *zpp = VTOZ(vp); 302 return (0); 303 } else { 304 error = zfs_match_find(zfsvfs, dzp, name, exact, 305 update, direntflags, realpnp, &zoid); 306 } 307 } 308 if (error) { 309 if (error != ENOENT || (flag & ZEXISTS)) { 310 zfs_dirent_unlock(dl); 311 return (error); 312 } 313 } else { 314 if (flag & ZNEW) { 315 zfs_dirent_unlock(dl); 316 return (SET_ERROR(EEXIST)); 317 } 318 error = zfs_zget(zfsvfs, zoid, zpp); 319 if (error) { 320 zfs_dirent_unlock(dl); 321 return (error); 322 } 323 if (!(flag & ZXATTR) && update) 324 dnlc_update(ZTOV(dzp), name, ZTOV(*zpp)); 325 } 326 327 *dlpp = dl; 328 329 return (0); 330} 331 332/* 333 * Unlock this directory entry and wake anyone who was waiting for it. 334 */ 335void 336zfs_dirent_unlock(zfs_dirlock_t *dl) 337{ 338 znode_t *dzp = dl->dl_dzp; 339 zfs_dirlock_t **prev_dl, *cur_dl; 340 341 mutex_enter(&dzp->z_lock); 342 343 if (!dl->dl_namelock) 344 rw_exit(&dzp->z_name_lock); 345 346 if (dl->dl_sharecnt > 1) { 347 dl->dl_sharecnt--; 348 mutex_exit(&dzp->z_lock); 349 return; 350 } 351 prev_dl = &dzp->z_dirlocks; 352 while ((cur_dl = *prev_dl) != dl) 353 prev_dl = &cur_dl->dl_next; 354 *prev_dl = dl->dl_next; 355 cv_broadcast(&dl->dl_cv); 356 mutex_exit(&dzp->z_lock); 357 358 cv_destroy(&dl->dl_cv); 359 kmem_free(dl, sizeof (*dl) + dl->dl_namesize); 360} 361 362/* 363 * Look up an entry in a directory. 364 * 365 * NOTE: '.' and '..' are handled as special cases because 366 * no directory entries are actually stored for them. If this is 367 * the root of a filesystem, then '.zfs' is also treated as a 368 * special pseudo-directory. 369 */ 370int 371zfs_dirlook(znode_t *dzp, char *name, vnode_t **vpp, int flags, 372 int *deflg, pathname_t *rpnp) 373{ 374 zfs_dirlock_t *dl; 375 znode_t *zp; 376 int error = 0; 377 uint64_t parent; 378 int unlinked; 379 380 if (name[0] == 0 || (name[0] == '.' && name[1] == 0)) { 381 mutex_enter(&dzp->z_lock); 382 unlinked = dzp->z_unlinked; 383 mutex_exit(&dzp->z_lock); 384 if (unlinked) 385 return (ENOENT); 386 387 *vpp = ZTOV(dzp); 388 VN_HOLD(*vpp); 389 } else if (name[0] == '.' && name[1] == '.' && name[2] == 0) { 390 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 391 392 /* 393 * If we are a snapshot mounted under .zfs, return 394 * the vp for the snapshot directory. 395 */ 396 if ((error = sa_lookup(dzp->z_sa_hdl, 397 SA_ZPL_PARENT(zfsvfs), &parent, sizeof (parent))) != 0) 398 return (error); 399 if (parent == dzp->z_id && zfsvfs->z_parent != zfsvfs) { 400 error = zfsctl_root_lookup(zfsvfs->z_parent->z_ctldir, 401 "snapshot", vpp, NULL, 0, NULL, kcred, 402 NULL, NULL, NULL); 403 return (error); 404 } 405 406 mutex_enter(&dzp->z_lock); 407 unlinked = dzp->z_unlinked; 408 mutex_exit(&dzp->z_lock); 409 if (unlinked) 410 return (ENOENT); 411 412 rw_enter(&dzp->z_parent_lock, RW_READER); 413 error = zfs_zget(zfsvfs, parent, &zp); 414 if (error == 0) 415 *vpp = ZTOV(zp); 416 rw_exit(&dzp->z_parent_lock); 417 } else if (zfs_has_ctldir(dzp) && strcmp(name, ZFS_CTLDIR_NAME) == 0) { 418 *vpp = zfsctl_root(dzp); 419 } else { 420 int zf; 421 422 zf = ZEXISTS | ZSHARED; 423 if (flags & FIGNORECASE) 424 zf |= ZCILOOK; 425 426 error = zfs_dirent_lock(&dl, dzp, name, &zp, zf, deflg, rpnp); 427 if (error == 0) { 428 *vpp = ZTOV(zp); 429 zfs_dirent_unlock(dl); 430 dzp->z_zn_prefetch = B_TRUE; /* enable prefetching */ 431 } 432 rpnp = NULL; 433 } 434 435 if ((flags & FIGNORECASE) && rpnp && !error) 436 (void) strlcpy(rpnp->pn_buf, name, rpnp->pn_bufsize); 437 438 return (error); 439} 440 441/* 442 * unlinked Set (formerly known as the "delete queue") Error Handling 443 * 444 * When dealing with the unlinked set, we dmu_tx_hold_zap(), but we 445 * don't specify the name of the entry that we will be manipulating. We 446 * also fib and say that we won't be adding any new entries to the 447 * unlinked set, even though we might (this is to lower the minimum file 448 * size that can be deleted in a full filesystem). So on the small 449 * chance that the nlink list is using a fat zap (ie. has more than 450 * 2000 entries), we *may* not pre-read a block that's needed. 451 * Therefore it is remotely possible for some of the assertions 452 * regarding the unlinked set below to fail due to i/o error. On a 453 * nondebug system, this will result in the space being leaked. 454 */ 455void 456zfs_unlinked_add(znode_t *zp, dmu_tx_t *tx) 457{ 458 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 459 460 ASSERT(zp->z_unlinked); 461 ASSERT(zp->z_links == 0); 462 463 VERIFY3U(0, ==, 464 zap_add_int(zfsvfs->z_os, zfsvfs->z_unlinkedobj, zp->z_id, tx)); 465} 466 467/* 468 * Clean up any znodes that had no links when we either crashed or 469 * (force) umounted the file system. 470 */ 471void 472zfs_unlinked_drain(zfsvfs_t *zfsvfs) 473{ 474 zap_cursor_t zc; 475 zap_attribute_t zap; 476 dmu_object_info_t doi; 477 znode_t *zp; 478 int error; 479 480 /* 481 * Interate over the contents of the unlinked set. 482 */ 483 for (zap_cursor_init(&zc, zfsvfs->z_os, zfsvfs->z_unlinkedobj); 484 zap_cursor_retrieve(&zc, &zap) == 0; 485 zap_cursor_advance(&zc)) { 486 487 /* 488 * See what kind of object we have in list 489 */ 490 491 error = dmu_object_info(zfsvfs->z_os, 492 zap.za_first_integer, &doi); 493 if (error != 0) 494 continue; 495 496 ASSERT((doi.doi_type == DMU_OT_PLAIN_FILE_CONTENTS) || 497 (doi.doi_type == DMU_OT_DIRECTORY_CONTENTS)); 498 /* 499 * We need to re-mark these list entries for deletion, 500 * so we pull them back into core and set zp->z_unlinked. 501 */ 502 error = zfs_zget(zfsvfs, zap.za_first_integer, &zp); 503 504 /* 505 * We may pick up znodes that are already marked for deletion. 506 * This could happen during the purge of an extended attribute 507 * directory. All we need to do is skip over them, since they 508 * are already in the system marked z_unlinked. 509 */ 510 if (error != 0) 511 continue; 512 513 zp->z_unlinked = B_TRUE; 514 VN_RELE(ZTOV(zp)); 515 } 516 zap_cursor_fini(&zc); 517} 518 519/* 520 * Delete the entire contents of a directory. Return a count 521 * of the number of entries that could not be deleted. If we encounter 522 * an error, return a count of at least one so that the directory stays 523 * in the unlinked set. 524 * 525 * NOTE: this function assumes that the directory is inactive, 526 * so there is no need to lock its entries before deletion. 527 * Also, it assumes the directory contents is *only* regular 528 * files. 529 */ 530static int 531zfs_purgedir(znode_t *dzp) 532{ 533 zap_cursor_t zc; 534 zap_attribute_t zap; 535 znode_t *xzp; 536 dmu_tx_t *tx; 537 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 538 zfs_dirlock_t dl; 539 int skipped = 0; 540 int error; 541 542 for (zap_cursor_init(&zc, zfsvfs->z_os, dzp->z_id); 543 (error = zap_cursor_retrieve(&zc, &zap)) == 0; 544 zap_cursor_advance(&zc)) { 545 error = zfs_zget(zfsvfs, 546 ZFS_DIRENT_OBJ(zap.za_first_integer), &xzp); 547 if (error) { 548 skipped += 1; 549 continue; 550 } 551 552 ASSERT((ZTOV(xzp)->v_type == VREG) || 553 (ZTOV(xzp)->v_type == VLNK)); 554 555 tx = dmu_tx_create(zfsvfs->z_os); 556 dmu_tx_hold_sa(tx, dzp->z_sa_hdl, B_FALSE); 557 dmu_tx_hold_zap(tx, dzp->z_id, FALSE, zap.za_name); 558 dmu_tx_hold_sa(tx, xzp->z_sa_hdl, B_FALSE); 559 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL); 560 /* Is this really needed ? */ 561 zfs_sa_upgrade_txholds(tx, xzp); 562 dmu_tx_mark_netfree(tx); 563 error = dmu_tx_assign(tx, TXG_WAIT); 564 if (error) { 565 dmu_tx_abort(tx); 566 VN_RELE(ZTOV(xzp)); 567 skipped += 1; 568 continue; 569 } 570 bzero(&dl, sizeof (dl)); 571 dl.dl_dzp = dzp; 572 dl.dl_name = zap.za_name; 573 574 error = zfs_link_destroy(&dl, xzp, tx, 0, NULL); 575 if (error) 576 skipped += 1; 577 dmu_tx_commit(tx); 578 579 VN_RELE(ZTOV(xzp)); 580 } 581 zap_cursor_fini(&zc); 582 if (error != ENOENT) 583 skipped += 1; 584 return (skipped); 585} 586 587void 588zfs_rmnode(znode_t *zp) 589{ 590 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 591 objset_t *os = zfsvfs->z_os; 592 znode_t *xzp = NULL; 593 dmu_tx_t *tx; 594 uint64_t acl_obj; 595 uint64_t xattr_obj; 596 int error; 597 598 ASSERT(zp->z_links == 0); 599 600 /* 601 * If this is an attribute directory, purge its contents. 602 */ 603 if (ZTOV(zp) != NULL && ZTOV(zp)->v_type == VDIR && 604 (zp->z_pflags & ZFS_XATTR)) { 605 if (zfs_purgedir(zp) != 0) { 606 /* 607 * Not enough space to delete some xattrs. 608 * Leave it in the unlinked set. 609 */ 610 zfs_znode_dmu_fini(zp); 611 zfs_znode_free(zp); 612 return; 613 } 614 } 615 616 /* 617 * Free up all the data in the file. 618 */ 619 error = dmu_free_long_range(os, zp->z_id, 0, DMU_OBJECT_END); 620 if (error) { 621 /* 622 * Not enough space. Leave the file in the unlinked set. 623 */ 624 zfs_znode_dmu_fini(zp); 625 zfs_znode_free(zp); 626 return; 627 } 628 629 /* 630 * If the file has extended attributes, we're going to unlink 631 * the xattr dir. 632 */ 633 error = sa_lookup(zp->z_sa_hdl, SA_ZPL_XATTR(zfsvfs), 634 &xattr_obj, sizeof (xattr_obj)); 635 if (error == 0 && xattr_obj) { 636 error = zfs_zget(zfsvfs, xattr_obj, &xzp); 637 ASSERT(error == 0); 638 } 639 640 acl_obj = zfs_external_acl(zp); 641 642 /* 643 * Set up the final transaction. 644 */ 645 tx = dmu_tx_create(os); 646 dmu_tx_hold_free(tx, zp->z_id, 0, DMU_OBJECT_END); 647 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL); 648 if (xzp) { 649 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, TRUE, NULL); 650 dmu_tx_hold_sa(tx, xzp->z_sa_hdl, B_FALSE); 651 } 652 if (acl_obj) 653 dmu_tx_hold_free(tx, acl_obj, 0, DMU_OBJECT_END); 654 655 zfs_sa_upgrade_txholds(tx, zp); 656 error = dmu_tx_assign(tx, TXG_WAIT); 657 if (error) { 658 /* 659 * Not enough space to delete the file. Leave it in the 660 * unlinked set, leaking it until the fs is remounted (at 661 * which point we'll call zfs_unlinked_drain() to process it). 662 */ 663 dmu_tx_abort(tx); 664 zfs_znode_dmu_fini(zp); 665 zfs_znode_free(zp); 666 goto out; 667 } 668 669 if (xzp) { 670 ASSERT(error == 0); 671 mutex_enter(&xzp->z_lock); 672 xzp->z_unlinked = B_TRUE; /* mark xzp for deletion */ 673 xzp->z_links = 0; /* no more links to it */ 674 VERIFY(0 == sa_update(xzp->z_sa_hdl, SA_ZPL_LINKS(zfsvfs), 675 &xzp->z_links, sizeof (xzp->z_links), tx)); 676 mutex_exit(&xzp->z_lock); 677 zfs_unlinked_add(xzp, tx); 678 } 679 680 /* Remove this znode from the unlinked set */ 681 VERIFY3U(0, ==, 682 zap_remove_int(zfsvfs->z_os, zfsvfs->z_unlinkedobj, zp->z_id, tx)); 683 684 zfs_znode_delete(zp, tx); 685 686 dmu_tx_commit(tx); 687out: 688 if (xzp) 689 VN_RELE(ZTOV(xzp)); 690} 691 692static uint64_t 693zfs_dirent(znode_t *zp, uint64_t mode) 694{ 695 uint64_t de = zp->z_id; 696 697 if (zp->z_zfsvfs->z_version >= ZPL_VERSION_DIRENT_TYPE) 698 de |= IFTODT(mode) << 60; 699 return (de); 700} 701 702/* 703 * Link zp into dl. Can only fail if zp has been unlinked. 704 */ 705int 706zfs_link_create(zfs_dirlock_t *dl, znode_t *zp, dmu_tx_t *tx, int flag) 707{ 708 znode_t *dzp = dl->dl_dzp; 709 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 710 vnode_t *vp = ZTOV(zp); 711 uint64_t value; 712 int zp_is_dir = (vp->v_type == VDIR); 713 sa_bulk_attr_t bulk[5]; 714 uint64_t mtime[2], ctime[2]; 715 int count = 0; 716 int error; 717 718 mutex_enter(&zp->z_lock); 719 720 if (!(flag & ZRENAMING)) { 721 if (zp->z_unlinked) { /* no new links to unlinked zp */ 722 ASSERT(!(flag & (ZNEW | ZEXISTS))); 723 mutex_exit(&zp->z_lock); 724 return (SET_ERROR(ENOENT)); 725 } 726 zp->z_links++; 727 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_LINKS(zfsvfs), NULL, 728 &zp->z_links, sizeof (zp->z_links)); 729 730 } 731 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_PARENT(zfsvfs), NULL, 732 &dzp->z_id, sizeof (dzp->z_id)); 733 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zfsvfs), NULL, 734 &zp->z_pflags, sizeof (zp->z_pflags)); 735 736 if (!(flag & ZNEW)) { 737 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL, 738 ctime, sizeof (ctime)); 739 zfs_tstamp_update_setup(zp, STATE_CHANGED, mtime, 740 ctime, B_TRUE); 741 } 742 error = sa_bulk_update(zp->z_sa_hdl, bulk, count, tx); 743 ASSERT(error == 0); 744 745 mutex_exit(&zp->z_lock); 746 747 mutex_enter(&dzp->z_lock); 748 dzp->z_size++; 749 dzp->z_links += zp_is_dir; 750 count = 0; 751 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_SIZE(zfsvfs), NULL, 752 &dzp->z_size, sizeof (dzp->z_size)); 753 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_LINKS(zfsvfs), NULL, 754 &dzp->z_links, sizeof (dzp->z_links)); 755 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs), NULL, 756 mtime, sizeof (mtime)); 757 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL, 758 ctime, sizeof (ctime)); 759 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zfsvfs), NULL, 760 &dzp->z_pflags, sizeof (dzp->z_pflags)); 761 zfs_tstamp_update_setup(dzp, CONTENT_MODIFIED, mtime, ctime, B_TRUE); 762 error = sa_bulk_update(dzp->z_sa_hdl, bulk, count, tx); 763 ASSERT(error == 0); 764 mutex_exit(&dzp->z_lock); 765 766 value = zfs_dirent(zp, zp->z_mode); 767 error = zap_add(zp->z_zfsvfs->z_os, dzp->z_id, dl->dl_name, 768 8, 1, &value, tx); 769 ASSERT(error == 0); 770 771 dnlc_update(ZTOV(dzp), dl->dl_name, vp); 772 773 return (0); 774} 775 776static int 777zfs_dropname(zfs_dirlock_t *dl, znode_t *zp, znode_t *dzp, dmu_tx_t *tx, 778 int flag) 779{ 780 int error; 781 782 if (zp->z_zfsvfs->z_norm) { 783 if (((zp->z_zfsvfs->z_case == ZFS_CASE_INSENSITIVE) && 784 (flag & ZCIEXACT)) || 785 ((zp->z_zfsvfs->z_case == ZFS_CASE_MIXED) && 786 !(flag & ZCILOOK))) 787 error = zap_remove_norm(zp->z_zfsvfs->z_os, 788 dzp->z_id, dl->dl_name, MT_EXACT, tx); 789 else 790 error = zap_remove_norm(zp->z_zfsvfs->z_os, 791 dzp->z_id, dl->dl_name, MT_FIRST, tx); 792 } else { 793 error = zap_remove(zp->z_zfsvfs->z_os, 794 dzp->z_id, dl->dl_name, tx); 795 } 796 797 return (error); 798} 799 800/* 801 * Unlink zp from dl, and mark zp for deletion if this was the last link. 802 * Can fail if zp is a mount point (EBUSY) or a non-empty directory (EEXIST). 803 * If 'unlinkedp' is NULL, we put unlinked znodes on the unlinked list. 804 * If it's non-NULL, we use it to indicate whether the znode needs deletion, 805 * and it's the caller's job to do it. 806 */ 807int 808zfs_link_destroy(zfs_dirlock_t *dl, znode_t *zp, dmu_tx_t *tx, int flag, 809 boolean_t *unlinkedp) 810{ 811 znode_t *dzp = dl->dl_dzp; 812 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 813 vnode_t *vp = ZTOV(zp); 814 int zp_is_dir = (vp->v_type == VDIR); 815 boolean_t unlinked = B_FALSE; 816 sa_bulk_attr_t bulk[5]; 817 uint64_t mtime[2], ctime[2]; 818 int count = 0; 819 int error; 820 821 dnlc_remove(ZTOV(dzp), dl->dl_name); 822 823 if (!(flag & ZRENAMING)) { 824 if (vn_vfswlock(vp)) /* prevent new mounts on zp */ 825 return (SET_ERROR(EBUSY)); 826 827 if (vn_ismntpt(vp)) { /* don't remove mount point */ 828 vn_vfsunlock(vp); 829 return (SET_ERROR(EBUSY)); 830 } 831 832 mutex_enter(&zp->z_lock); 833 834 if (zp_is_dir && !zfs_dirempty(zp)) { 835 mutex_exit(&zp->z_lock); 836 vn_vfsunlock(vp); 837#ifdef illumos 838 return (SET_ERROR(EEXIST)); 839#else 840 return (SET_ERROR(ENOTEMPTY)); 841#endif 842 } 843 844 /* 845 * If we get here, we are going to try to remove the object. 846 * First try removing the name from the directory; if that 847 * fails, return the error. 848 */ 849 error = zfs_dropname(dl, zp, dzp, tx, flag); 850 if (error != 0) { 851 mutex_exit(&zp->z_lock); 852 vn_vfsunlock(vp); 853 return (error); 854 } 855 856 if (zp->z_links <= zp_is_dir) { 857 zfs_panic_recover("zfs: link count on vnode %p is %u, " 858 "should be at least %u", zp->z_vnode, 859 (int)zp->z_links, 860 zp_is_dir + 1); 861 zp->z_links = zp_is_dir + 1; 862 } 863 if (--zp->z_links == zp_is_dir) { 864 zp->z_unlinked = B_TRUE; 865 zp->z_links = 0; 866 unlinked = B_TRUE; 867 } else { 868 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), 869 NULL, &ctime, sizeof (ctime)); 870 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zfsvfs), 871 NULL, &zp->z_pflags, sizeof (zp->z_pflags)); 872 zfs_tstamp_update_setup(zp, STATE_CHANGED, mtime, ctime, 873 B_TRUE); 874 } 875 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_LINKS(zfsvfs), 876 NULL, &zp->z_links, sizeof (zp->z_links)); 877 error = sa_bulk_update(zp->z_sa_hdl, bulk, count, tx); 878 count = 0; 879 ASSERT(error == 0); 880 mutex_exit(&zp->z_lock); 881 vn_vfsunlock(vp); 882 } else { 883 error = zfs_dropname(dl, zp, dzp, tx, flag); 884 if (error != 0) 885 return (error); 886 } 887 888 mutex_enter(&dzp->z_lock); 889 dzp->z_size--; /* one dirent removed */ 890 dzp->z_links -= zp_is_dir; /* ".." link from zp */ 891 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_LINKS(zfsvfs), 892 NULL, &dzp->z_links, sizeof (dzp->z_links)); 893 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_SIZE(zfsvfs), 894 NULL, &dzp->z_size, sizeof (dzp->z_size)); 895 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), 896 NULL, ctime, sizeof (ctime)); 897 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs), 898 NULL, mtime, sizeof (mtime)); 899 SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zfsvfs), 900 NULL, &dzp->z_pflags, sizeof (dzp->z_pflags)); 901 zfs_tstamp_update_setup(dzp, CONTENT_MODIFIED, mtime, ctime, B_TRUE); 902 error = sa_bulk_update(dzp->z_sa_hdl, bulk, count, tx); 903 ASSERT(error == 0); 904 mutex_exit(&dzp->z_lock); 905 906 if (unlinkedp != NULL) 907 *unlinkedp = unlinked; 908 else if (unlinked) 909 zfs_unlinked_add(zp, tx); 910 911 return (0); 912} 913 914/* 915 * Indicate whether the directory is empty. Works with or without z_lock 916 * held, but can only be consider a hint in the latter case. Returns true 917 * if only "." and ".." remain and there's no work in progress. 918 */ 919boolean_t 920zfs_dirempty(znode_t *dzp) 921{ 922 return (dzp->z_size == 2 && dzp->z_dirlocks == 0); 923} 924 925int 926zfs_make_xattrdir(znode_t *zp, vattr_t *vap, vnode_t **xvpp, cred_t *cr) 927{ 928 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 929 znode_t *xzp; 930 dmu_tx_t *tx; 931 int error; 932 zfs_acl_ids_t acl_ids; 933 boolean_t fuid_dirtied; 934 uint64_t parent; 935 936 *xvpp = NULL; 937 938 /* 939 * In FreeBSD, access checking for creating an EA is being done 940 * in zfs_setextattr(), 941 */ 942#ifndef __FreeBSD_kernel__ 943 if (error = zfs_zaccess(zp, ACE_WRITE_NAMED_ATTRS, 0, B_FALSE, cr)) 944 return (error); 945#endif 946 947 if ((error = zfs_acl_ids_create(zp, IS_XATTR, vap, cr, NULL, 948 &acl_ids)) != 0) 949 return (error); 950 if (zfs_acl_ids_overquota(zfsvfs, &acl_ids)) { 951 zfs_acl_ids_free(&acl_ids); 952 return (SET_ERROR(EDQUOT)); 953 } 954 955 getnewvnode_reserve(1); 956 957 tx = dmu_tx_create(zfsvfs->z_os); 958 dmu_tx_hold_sa_create(tx, acl_ids.z_aclp->z_acl_bytes + 959 ZFS_SA_BASE_ATTR_SIZE); 960 dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_TRUE); 961 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL); 962 fuid_dirtied = zfsvfs->z_fuid_dirty; 963 if (fuid_dirtied) 964 zfs_fuid_txhold(zfsvfs, tx); 965 error = dmu_tx_assign(tx, TXG_WAIT); 966 if (error) { 967 zfs_acl_ids_free(&acl_ids); 968 dmu_tx_abort(tx); 969 return (error); 970 } 971 zfs_mknode(zp, vap, tx, cr, IS_XATTR, &xzp, &acl_ids); 972 973 if (fuid_dirtied) 974 zfs_fuid_sync(zfsvfs, tx); 975 976#ifdef DEBUG 977 error = sa_lookup(xzp->z_sa_hdl, SA_ZPL_PARENT(zfsvfs), 978 &parent, sizeof (parent)); 979 ASSERT(error == 0 && parent == zp->z_id); 980#endif 981 982 VERIFY(0 == sa_update(zp->z_sa_hdl, SA_ZPL_XATTR(zfsvfs), &xzp->z_id, 983 sizeof (xzp->z_id), tx)); 984 985 (void) zfs_log_create(zfsvfs->z_log, tx, TX_MKXATTR, zp, 986 xzp, "", NULL, acl_ids.z_fuidp, vap); 987 988 zfs_acl_ids_free(&acl_ids); 989 dmu_tx_commit(tx); 990 991 getnewvnode_drop_reserve(); 992 993 *xvpp = ZTOV(xzp); 994 995 return (0); 996} 997 998/* 999 * Return a znode for the extended attribute directory for zp. 1000 * ** If the directory does not already exist, it is created ** 1001 * 1002 * IN: zp - znode to obtain attribute directory from 1003 * cr - credentials of caller 1004 * flags - flags from the VOP_LOOKUP call 1005 * 1006 * OUT: xzpp - pointer to extended attribute znode 1007 * 1008 * RETURN: 0 on success 1009 * error number on failure 1010 */ 1011int 1012zfs_get_xattrdir(znode_t *zp, vnode_t **xvpp, cred_t *cr, int flags) 1013{ 1014 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 1015 znode_t *xzp; 1016 zfs_dirlock_t *dl; 1017 vattr_t va; 1018 int error; 1019top: 1020 error = zfs_dirent_lock(&dl, zp, "", &xzp, ZXATTR, NULL, NULL); 1021 if (error) 1022 return (error); 1023 1024 if (xzp != NULL) { 1025 *xvpp = ZTOV(xzp); 1026 zfs_dirent_unlock(dl); 1027 return (0); 1028 } 1029 1030 1031 if (!(flags & CREATE_XATTR_DIR)) { 1032 zfs_dirent_unlock(dl); 1033#ifdef illumos 1034 return (SET_ERROR(ENOENT)); 1035#else 1036 return (SET_ERROR(ENOATTR)); 1037#endif 1038 } 1039 1040 if (zfsvfs->z_vfs->vfs_flag & VFS_RDONLY) { 1041 zfs_dirent_unlock(dl); 1042 return (SET_ERROR(EROFS)); 1043 } 1044 1045 /* 1046 * The ability to 'create' files in an attribute 1047 * directory comes from the write_xattr permission on the base file. 1048 * 1049 * The ability to 'search' an attribute directory requires 1050 * read_xattr permission on the base file. 1051 * 1052 * Once in a directory the ability to read/write attributes 1053 * is controlled by the permissions on the attribute file. 1054 */ 1055 va.va_mask = AT_TYPE | AT_MODE | AT_UID | AT_GID; 1056 va.va_type = VDIR; 1057 va.va_mode = S_IFDIR | S_ISVTX | 0777; 1058 zfs_fuid_map_ids(zp, cr, &va.va_uid, &va.va_gid); 1059 1060 error = zfs_make_xattrdir(zp, &va, xvpp, cr); 1061 zfs_dirent_unlock(dl); 1062 1063 if (error == ERESTART) { 1064 /* NB: we already did dmu_tx_wait() if necessary */ 1065 goto top; 1066 } 1067 if (error == 0) 1068 VOP_UNLOCK(*xvpp, 0); 1069 1070 return (error); 1071} 1072 1073/* 1074 * Decide whether it is okay to remove within a sticky directory. 1075 * 1076 * In sticky directories, write access is not sufficient; 1077 * you can remove entries from a directory only if: 1078 * 1079 * you own the directory, 1080 * you own the entry, 1081 * the entry is a plain file and you have write access, 1082 * or you are privileged (checked in secpolicy...). 1083 * 1084 * The function returns 0 if remove access is granted. 1085 */ 1086int 1087zfs_sticky_remove_access(znode_t *zdp, znode_t *zp, cred_t *cr) 1088{ 1089 uid_t uid; 1090 uid_t downer; 1091 uid_t fowner; 1092 zfsvfs_t *zfsvfs = zdp->z_zfsvfs; 1093 1094 if (zdp->z_zfsvfs->z_replay) 1095 return (0); 1096 1097 if ((zdp->z_mode & S_ISVTX) == 0) 1098 return (0); 1099 1100 downer = zfs_fuid_map_id(zfsvfs, zdp->z_uid, cr, ZFS_OWNER); 1101 fowner = zfs_fuid_map_id(zfsvfs, zp->z_uid, cr, ZFS_OWNER); 1102 1103 if ((uid = crgetuid(cr)) == downer || uid == fowner || 1104 (ZTOV(zp)->v_type == VREG && 1105 zfs_zaccess(zp, ACE_WRITE_DATA, 0, B_FALSE, cr) == 0)) 1106 return (0); 1107 else 1108 return (secpolicy_vnode_remove(ZTOV(zp), cr)); 1109} 1110