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 https://opensource.org/licenses/CDDL-1.0. 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) 2012, 2018 by Delphix. All rights reserved. 24 */ 25 26 /* Portions Copyright 2010 Robert Milkowski */ 27 28 #include <sys/types.h> 29 #include <sys/param.h> 30 #include <sys/sysmacros.h> 31 #include <sys/kmem.h> 32 #include <sys/pathname.h> 33 #include <sys/vnode.h> 34 #include <sys/vfs.h> 35 #include <sys/mntent.h> 36 #include <sys/cmn_err.h> 37 #include <sys/zfs_znode.h> 38 #include <sys/zfs_vnops.h> 39 #include <sys/zfs_dir.h> 40 #include <sys/zil.h> 41 #include <sys/fs/zfs.h> 42 #include <sys/dmu.h> 43 #include <sys/dsl_prop.h> 44 #include <sys/dsl_dataset.h> 45 #include <sys/dsl_deleg.h> 46 #include <sys/spa.h> 47 #include <sys/zap.h> 48 #include <sys/sa.h> 49 #include <sys/sa_impl.h> 50 #include <sys/policy.h> 51 #include <sys/atomic.h> 52 #include <sys/zfs_ioctl.h> 53 #include <sys/zfs_ctldir.h> 54 #include <sys/zfs_fuid.h> 55 #include <sys/zfs_quota.h> 56 #include <sys/sunddi.h> 57 #include <sys/dmu_objset.h> 58 #include <sys/dsl_dir.h> 59 #include <sys/objlist.h> 60 #include <sys/zpl.h> 61 #include <linux/vfs_compat.h> 62 #include "zfs_comutil.h" 63 64 enum { 65 TOKEN_RO, 66 TOKEN_RW, 67 TOKEN_SETUID, 68 TOKEN_NOSETUID, 69 TOKEN_EXEC, 70 TOKEN_NOEXEC, 71 TOKEN_DEVICES, 72 TOKEN_NODEVICES, 73 TOKEN_DIRXATTR, 74 TOKEN_SAXATTR, 75 TOKEN_XATTR, 76 TOKEN_NOXATTR, 77 TOKEN_ATIME, 78 TOKEN_NOATIME, 79 TOKEN_RELATIME, 80 TOKEN_NORELATIME, 81 TOKEN_NBMAND, 82 TOKEN_NONBMAND, 83 TOKEN_MNTPOINT, 84 TOKEN_LAST, 85 }; 86 87 static const match_table_t zpl_tokens = { 88 { TOKEN_RO, MNTOPT_RO }, 89 { TOKEN_RW, MNTOPT_RW }, 90 { TOKEN_SETUID, MNTOPT_SETUID }, 91 { TOKEN_NOSETUID, MNTOPT_NOSETUID }, 92 { TOKEN_EXEC, MNTOPT_EXEC }, 93 { TOKEN_NOEXEC, MNTOPT_NOEXEC }, 94 { TOKEN_DEVICES, MNTOPT_DEVICES }, 95 { TOKEN_NODEVICES, MNTOPT_NODEVICES }, 96 { TOKEN_DIRXATTR, MNTOPT_DIRXATTR }, 97 { TOKEN_SAXATTR, MNTOPT_SAXATTR }, 98 { TOKEN_XATTR, MNTOPT_XATTR }, 99 { TOKEN_NOXATTR, MNTOPT_NOXATTR }, 100 { TOKEN_ATIME, MNTOPT_ATIME }, 101 { TOKEN_NOATIME, MNTOPT_NOATIME }, 102 { TOKEN_RELATIME, MNTOPT_RELATIME }, 103 { TOKEN_NORELATIME, MNTOPT_NORELATIME }, 104 { TOKEN_NBMAND, MNTOPT_NBMAND }, 105 { TOKEN_NONBMAND, MNTOPT_NONBMAND }, 106 { TOKEN_MNTPOINT, MNTOPT_MNTPOINT "=%s" }, 107 { TOKEN_LAST, NULL }, 108 }; 109 110 static void 111 zfsvfs_vfs_free(vfs_t *vfsp) 112 { 113 if (vfsp != NULL) { 114 if (vfsp->vfs_mntpoint != NULL) 115 kmem_strfree(vfsp->vfs_mntpoint); 116 117 kmem_free(vfsp, sizeof (vfs_t)); 118 } 119 } 120 121 static int 122 zfsvfs_parse_option(char *option, int token, substring_t *args, vfs_t *vfsp) 123 { 124 switch (token) { 125 case TOKEN_RO: 126 vfsp->vfs_readonly = B_TRUE; 127 vfsp->vfs_do_readonly = B_TRUE; 128 break; 129 case TOKEN_RW: 130 vfsp->vfs_readonly = B_FALSE; 131 vfsp->vfs_do_readonly = B_TRUE; 132 break; 133 case TOKEN_SETUID: 134 vfsp->vfs_setuid = B_TRUE; 135 vfsp->vfs_do_setuid = B_TRUE; 136 break; 137 case TOKEN_NOSETUID: 138 vfsp->vfs_setuid = B_FALSE; 139 vfsp->vfs_do_setuid = B_TRUE; 140 break; 141 case TOKEN_EXEC: 142 vfsp->vfs_exec = B_TRUE; 143 vfsp->vfs_do_exec = B_TRUE; 144 break; 145 case TOKEN_NOEXEC: 146 vfsp->vfs_exec = B_FALSE; 147 vfsp->vfs_do_exec = B_TRUE; 148 break; 149 case TOKEN_DEVICES: 150 vfsp->vfs_devices = B_TRUE; 151 vfsp->vfs_do_devices = B_TRUE; 152 break; 153 case TOKEN_NODEVICES: 154 vfsp->vfs_devices = B_FALSE; 155 vfsp->vfs_do_devices = B_TRUE; 156 break; 157 case TOKEN_DIRXATTR: 158 vfsp->vfs_xattr = ZFS_XATTR_DIR; 159 vfsp->vfs_do_xattr = B_TRUE; 160 break; 161 case TOKEN_SAXATTR: 162 vfsp->vfs_xattr = ZFS_XATTR_SA; 163 vfsp->vfs_do_xattr = B_TRUE; 164 break; 165 case TOKEN_XATTR: 166 vfsp->vfs_xattr = ZFS_XATTR_DIR; 167 vfsp->vfs_do_xattr = B_TRUE; 168 break; 169 case TOKEN_NOXATTR: 170 vfsp->vfs_xattr = ZFS_XATTR_OFF; 171 vfsp->vfs_do_xattr = B_TRUE; 172 break; 173 case TOKEN_ATIME: 174 vfsp->vfs_atime = B_TRUE; 175 vfsp->vfs_do_atime = B_TRUE; 176 break; 177 case TOKEN_NOATIME: 178 vfsp->vfs_atime = B_FALSE; 179 vfsp->vfs_do_atime = B_TRUE; 180 break; 181 case TOKEN_RELATIME: 182 vfsp->vfs_relatime = B_TRUE; 183 vfsp->vfs_do_relatime = B_TRUE; 184 break; 185 case TOKEN_NORELATIME: 186 vfsp->vfs_relatime = B_FALSE; 187 vfsp->vfs_do_relatime = B_TRUE; 188 break; 189 case TOKEN_NBMAND: 190 vfsp->vfs_nbmand = B_TRUE; 191 vfsp->vfs_do_nbmand = B_TRUE; 192 break; 193 case TOKEN_NONBMAND: 194 vfsp->vfs_nbmand = B_FALSE; 195 vfsp->vfs_do_nbmand = B_TRUE; 196 break; 197 case TOKEN_MNTPOINT: 198 vfsp->vfs_mntpoint = match_strdup(&args[0]); 199 if (vfsp->vfs_mntpoint == NULL) 200 return (SET_ERROR(ENOMEM)); 201 202 break; 203 default: 204 break; 205 } 206 207 return (0); 208 } 209 210 /* 211 * Parse the raw mntopts and return a vfs_t describing the options. 212 */ 213 static int 214 zfsvfs_parse_options(char *mntopts, vfs_t **vfsp) 215 { 216 vfs_t *tmp_vfsp; 217 int error; 218 219 tmp_vfsp = kmem_zalloc(sizeof (vfs_t), KM_SLEEP); 220 221 if (mntopts != NULL) { 222 substring_t args[MAX_OPT_ARGS]; 223 char *tmp_mntopts, *p, *t; 224 int token; 225 226 tmp_mntopts = t = kmem_strdup(mntopts); 227 if (tmp_mntopts == NULL) 228 return (SET_ERROR(ENOMEM)); 229 230 while ((p = strsep(&t, ",")) != NULL) { 231 if (!*p) 232 continue; 233 234 args[0].to = args[0].from = NULL; 235 token = match_token(p, zpl_tokens, args); 236 error = zfsvfs_parse_option(p, token, args, tmp_vfsp); 237 if (error) { 238 kmem_strfree(tmp_mntopts); 239 zfsvfs_vfs_free(tmp_vfsp); 240 return (error); 241 } 242 } 243 244 kmem_strfree(tmp_mntopts); 245 } 246 247 *vfsp = tmp_vfsp; 248 249 return (0); 250 } 251 252 boolean_t 253 zfs_is_readonly(zfsvfs_t *zfsvfs) 254 { 255 return (!!(zfsvfs->z_sb->s_flags & SB_RDONLY)); 256 } 257 258 int 259 zfs_sync(struct super_block *sb, int wait, cred_t *cr) 260 { 261 (void) cr; 262 zfsvfs_t *zfsvfs = sb->s_fs_info; 263 264 /* 265 * Semantically, the only requirement is that the sync be initiated. 266 * The DMU syncs out txgs frequently, so there's nothing to do. 267 */ 268 if (!wait) 269 return (0); 270 271 if (zfsvfs != NULL) { 272 /* 273 * Sync a specific filesystem. 274 */ 275 dsl_pool_t *dp; 276 int error; 277 278 if ((error = zfs_enter(zfsvfs, FTAG)) != 0) 279 return (error); 280 dp = dmu_objset_pool(zfsvfs->z_os); 281 282 /* 283 * If the system is shutting down, then skip any 284 * filesystems which may exist on a suspended pool. 285 */ 286 if (spa_suspended(dp->dp_spa)) { 287 zfs_exit(zfsvfs, FTAG); 288 return (0); 289 } 290 291 if (zfsvfs->z_log != NULL) 292 zil_commit(zfsvfs->z_log, 0); 293 294 zfs_exit(zfsvfs, FTAG); 295 } else { 296 /* 297 * Sync all ZFS filesystems. This is what happens when you 298 * run sync(1). Unlike other filesystems, ZFS honors the 299 * request by waiting for all pools to commit all dirty data. 300 */ 301 spa_sync_allpools(); 302 } 303 304 return (0); 305 } 306 307 static void 308 atime_changed_cb(void *arg, uint64_t newval) 309 { 310 zfsvfs_t *zfsvfs = arg; 311 struct super_block *sb = zfsvfs->z_sb; 312 313 if (sb == NULL) 314 return; 315 /* 316 * Update SB_NOATIME bit in VFS super block. Since atime update is 317 * determined by atime_needs_update(), atime_needs_update() needs to 318 * return false if atime is turned off, and not unconditionally return 319 * false if atime is turned on. 320 */ 321 if (newval) 322 sb->s_flags &= ~SB_NOATIME; 323 else 324 sb->s_flags |= SB_NOATIME; 325 } 326 327 static void 328 relatime_changed_cb(void *arg, uint64_t newval) 329 { 330 ((zfsvfs_t *)arg)->z_relatime = newval; 331 } 332 333 static void 334 xattr_changed_cb(void *arg, uint64_t newval) 335 { 336 zfsvfs_t *zfsvfs = arg; 337 338 if (newval == ZFS_XATTR_OFF) { 339 zfsvfs->z_flags &= ~ZSB_XATTR; 340 } else { 341 zfsvfs->z_flags |= ZSB_XATTR; 342 343 if (newval == ZFS_XATTR_SA) 344 zfsvfs->z_xattr_sa = B_TRUE; 345 else 346 zfsvfs->z_xattr_sa = B_FALSE; 347 } 348 } 349 350 static void 351 acltype_changed_cb(void *arg, uint64_t newval) 352 { 353 zfsvfs_t *zfsvfs = arg; 354 355 switch (newval) { 356 case ZFS_ACLTYPE_NFSV4: 357 case ZFS_ACLTYPE_OFF: 358 zfsvfs->z_acl_type = ZFS_ACLTYPE_OFF; 359 zfsvfs->z_sb->s_flags &= ~SB_POSIXACL; 360 break; 361 case ZFS_ACLTYPE_POSIX: 362 #ifdef CONFIG_FS_POSIX_ACL 363 zfsvfs->z_acl_type = ZFS_ACLTYPE_POSIX; 364 zfsvfs->z_sb->s_flags |= SB_POSIXACL; 365 #else 366 zfsvfs->z_acl_type = ZFS_ACLTYPE_OFF; 367 zfsvfs->z_sb->s_flags &= ~SB_POSIXACL; 368 #endif /* CONFIG_FS_POSIX_ACL */ 369 break; 370 default: 371 break; 372 } 373 } 374 375 static void 376 blksz_changed_cb(void *arg, uint64_t newval) 377 { 378 zfsvfs_t *zfsvfs = arg; 379 ASSERT3U(newval, <=, spa_maxblocksize(dmu_objset_spa(zfsvfs->z_os))); 380 ASSERT3U(newval, >=, SPA_MINBLOCKSIZE); 381 ASSERT(ISP2(newval)); 382 383 zfsvfs->z_max_blksz = newval; 384 } 385 386 static void 387 readonly_changed_cb(void *arg, uint64_t newval) 388 { 389 zfsvfs_t *zfsvfs = arg; 390 struct super_block *sb = zfsvfs->z_sb; 391 392 if (sb == NULL) 393 return; 394 395 if (newval) 396 sb->s_flags |= SB_RDONLY; 397 else 398 sb->s_flags &= ~SB_RDONLY; 399 } 400 401 static void 402 devices_changed_cb(void *arg, uint64_t newval) 403 { 404 } 405 406 static void 407 setuid_changed_cb(void *arg, uint64_t newval) 408 { 409 } 410 411 static void 412 exec_changed_cb(void *arg, uint64_t newval) 413 { 414 } 415 416 static void 417 nbmand_changed_cb(void *arg, uint64_t newval) 418 { 419 zfsvfs_t *zfsvfs = arg; 420 struct super_block *sb = zfsvfs->z_sb; 421 422 if (sb == NULL) 423 return; 424 425 if (newval == TRUE) 426 sb->s_flags |= SB_MANDLOCK; 427 else 428 sb->s_flags &= ~SB_MANDLOCK; 429 } 430 431 static void 432 snapdir_changed_cb(void *arg, uint64_t newval) 433 { 434 ((zfsvfs_t *)arg)->z_show_ctldir = newval; 435 } 436 437 static void 438 acl_mode_changed_cb(void *arg, uint64_t newval) 439 { 440 zfsvfs_t *zfsvfs = arg; 441 442 zfsvfs->z_acl_mode = newval; 443 } 444 445 static void 446 acl_inherit_changed_cb(void *arg, uint64_t newval) 447 { 448 ((zfsvfs_t *)arg)->z_acl_inherit = newval; 449 } 450 451 static int 452 zfs_register_callbacks(vfs_t *vfsp) 453 { 454 struct dsl_dataset *ds = NULL; 455 objset_t *os = NULL; 456 zfsvfs_t *zfsvfs = NULL; 457 int error = 0; 458 459 ASSERT(vfsp); 460 zfsvfs = vfsp->vfs_data; 461 ASSERT(zfsvfs); 462 os = zfsvfs->z_os; 463 464 /* 465 * The act of registering our callbacks will destroy any mount 466 * options we may have. In order to enable temporary overrides 467 * of mount options, we stash away the current values and 468 * restore them after we register the callbacks. 469 */ 470 if (zfs_is_readonly(zfsvfs) || !spa_writeable(dmu_objset_spa(os))) { 471 vfsp->vfs_do_readonly = B_TRUE; 472 vfsp->vfs_readonly = B_TRUE; 473 } 474 475 /* 476 * Register property callbacks. 477 * 478 * It would probably be fine to just check for i/o error from 479 * the first prop_register(), but I guess I like to go 480 * overboard... 481 */ 482 ds = dmu_objset_ds(os); 483 dsl_pool_config_enter(dmu_objset_pool(os), FTAG); 484 error = dsl_prop_register(ds, 485 zfs_prop_to_name(ZFS_PROP_ATIME), atime_changed_cb, zfsvfs); 486 error = error ? error : dsl_prop_register(ds, 487 zfs_prop_to_name(ZFS_PROP_RELATIME), relatime_changed_cb, zfsvfs); 488 error = error ? error : dsl_prop_register(ds, 489 zfs_prop_to_name(ZFS_PROP_XATTR), xattr_changed_cb, zfsvfs); 490 error = error ? error : dsl_prop_register(ds, 491 zfs_prop_to_name(ZFS_PROP_RECORDSIZE), blksz_changed_cb, zfsvfs); 492 error = error ? error : dsl_prop_register(ds, 493 zfs_prop_to_name(ZFS_PROP_READONLY), readonly_changed_cb, zfsvfs); 494 error = error ? error : dsl_prop_register(ds, 495 zfs_prop_to_name(ZFS_PROP_DEVICES), devices_changed_cb, zfsvfs); 496 error = error ? error : dsl_prop_register(ds, 497 zfs_prop_to_name(ZFS_PROP_SETUID), setuid_changed_cb, zfsvfs); 498 error = error ? error : dsl_prop_register(ds, 499 zfs_prop_to_name(ZFS_PROP_EXEC), exec_changed_cb, zfsvfs); 500 error = error ? error : dsl_prop_register(ds, 501 zfs_prop_to_name(ZFS_PROP_SNAPDIR), snapdir_changed_cb, zfsvfs); 502 error = error ? error : dsl_prop_register(ds, 503 zfs_prop_to_name(ZFS_PROP_ACLTYPE), acltype_changed_cb, zfsvfs); 504 error = error ? error : dsl_prop_register(ds, 505 zfs_prop_to_name(ZFS_PROP_ACLMODE), acl_mode_changed_cb, zfsvfs); 506 error = error ? error : dsl_prop_register(ds, 507 zfs_prop_to_name(ZFS_PROP_ACLINHERIT), acl_inherit_changed_cb, 508 zfsvfs); 509 error = error ? error : dsl_prop_register(ds, 510 zfs_prop_to_name(ZFS_PROP_NBMAND), nbmand_changed_cb, zfsvfs); 511 dsl_pool_config_exit(dmu_objset_pool(os), FTAG); 512 if (error) 513 goto unregister; 514 515 /* 516 * Invoke our callbacks to restore temporary mount options. 517 */ 518 if (vfsp->vfs_do_readonly) 519 readonly_changed_cb(zfsvfs, vfsp->vfs_readonly); 520 if (vfsp->vfs_do_setuid) 521 setuid_changed_cb(zfsvfs, vfsp->vfs_setuid); 522 if (vfsp->vfs_do_exec) 523 exec_changed_cb(zfsvfs, vfsp->vfs_exec); 524 if (vfsp->vfs_do_devices) 525 devices_changed_cb(zfsvfs, vfsp->vfs_devices); 526 if (vfsp->vfs_do_xattr) 527 xattr_changed_cb(zfsvfs, vfsp->vfs_xattr); 528 if (vfsp->vfs_do_atime) 529 atime_changed_cb(zfsvfs, vfsp->vfs_atime); 530 if (vfsp->vfs_do_relatime) 531 relatime_changed_cb(zfsvfs, vfsp->vfs_relatime); 532 if (vfsp->vfs_do_nbmand) 533 nbmand_changed_cb(zfsvfs, vfsp->vfs_nbmand); 534 535 return (0); 536 537 unregister: 538 dsl_prop_unregister_all(ds, zfsvfs); 539 return (error); 540 } 541 542 /* 543 * Takes a dataset, a property, a value and that value's setpoint as 544 * found in the ZAP. Checks if the property has been changed in the vfs. 545 * If so, val and setpoint will be overwritten with updated content. 546 * Otherwise, they are left unchanged. 547 */ 548 int 549 zfs_get_temporary_prop(dsl_dataset_t *ds, zfs_prop_t zfs_prop, uint64_t *val, 550 char *setpoint) 551 { 552 int error; 553 zfsvfs_t *zfvp; 554 vfs_t *vfsp; 555 objset_t *os; 556 uint64_t tmp = *val; 557 558 error = dmu_objset_from_ds(ds, &os); 559 if (error != 0) 560 return (error); 561 562 if (dmu_objset_type(os) != DMU_OST_ZFS) 563 return (EINVAL); 564 565 mutex_enter(&os->os_user_ptr_lock); 566 zfvp = dmu_objset_get_user(os); 567 mutex_exit(&os->os_user_ptr_lock); 568 if (zfvp == NULL) 569 return (ESRCH); 570 571 vfsp = zfvp->z_vfs; 572 573 switch (zfs_prop) { 574 case ZFS_PROP_ATIME: 575 if (vfsp->vfs_do_atime) 576 tmp = vfsp->vfs_atime; 577 break; 578 case ZFS_PROP_RELATIME: 579 if (vfsp->vfs_do_relatime) 580 tmp = vfsp->vfs_relatime; 581 break; 582 case ZFS_PROP_DEVICES: 583 if (vfsp->vfs_do_devices) 584 tmp = vfsp->vfs_devices; 585 break; 586 case ZFS_PROP_EXEC: 587 if (vfsp->vfs_do_exec) 588 tmp = vfsp->vfs_exec; 589 break; 590 case ZFS_PROP_SETUID: 591 if (vfsp->vfs_do_setuid) 592 tmp = vfsp->vfs_setuid; 593 break; 594 case ZFS_PROP_READONLY: 595 if (vfsp->vfs_do_readonly) 596 tmp = vfsp->vfs_readonly; 597 break; 598 case ZFS_PROP_XATTR: 599 if (vfsp->vfs_do_xattr) 600 tmp = vfsp->vfs_xattr; 601 break; 602 case ZFS_PROP_NBMAND: 603 if (vfsp->vfs_do_nbmand) 604 tmp = vfsp->vfs_nbmand; 605 break; 606 default: 607 return (ENOENT); 608 } 609 610 if (tmp != *val) { 611 if (setpoint) 612 (void) strcpy(setpoint, "temporary"); 613 *val = tmp; 614 } 615 return (0); 616 } 617 618 /* 619 * Associate this zfsvfs with the given objset, which must be owned. 620 * This will cache a bunch of on-disk state from the objset in the 621 * zfsvfs. 622 */ 623 static int 624 zfsvfs_init(zfsvfs_t *zfsvfs, objset_t *os) 625 { 626 int error; 627 uint64_t val; 628 629 zfsvfs->z_max_blksz = SPA_OLD_MAXBLOCKSIZE; 630 zfsvfs->z_show_ctldir = ZFS_SNAPDIR_VISIBLE; 631 zfsvfs->z_os = os; 632 633 error = zfs_get_zplprop(os, ZFS_PROP_VERSION, &zfsvfs->z_version); 634 if (error != 0) 635 return (error); 636 if (zfsvfs->z_version > 637 zfs_zpl_version_map(spa_version(dmu_objset_spa(os)))) { 638 (void) printk("Can't mount a version %lld file system " 639 "on a version %lld pool\n. Pool must be upgraded to mount " 640 "this file system.\n", (u_longlong_t)zfsvfs->z_version, 641 (u_longlong_t)spa_version(dmu_objset_spa(os))); 642 return (SET_ERROR(ENOTSUP)); 643 } 644 error = zfs_get_zplprop(os, ZFS_PROP_NORMALIZE, &val); 645 if (error != 0) 646 return (error); 647 zfsvfs->z_norm = (int)val; 648 649 error = zfs_get_zplprop(os, ZFS_PROP_UTF8ONLY, &val); 650 if (error != 0) 651 return (error); 652 zfsvfs->z_utf8 = (val != 0); 653 654 error = zfs_get_zplprop(os, ZFS_PROP_CASE, &val); 655 if (error != 0) 656 return (error); 657 zfsvfs->z_case = (uint_t)val; 658 659 if ((error = zfs_get_zplprop(os, ZFS_PROP_ACLTYPE, &val)) != 0) 660 return (error); 661 zfsvfs->z_acl_type = (uint_t)val; 662 663 /* 664 * Fold case on file systems that are always or sometimes case 665 * insensitive. 666 */ 667 if (zfsvfs->z_case == ZFS_CASE_INSENSITIVE || 668 zfsvfs->z_case == ZFS_CASE_MIXED) 669 zfsvfs->z_norm |= U8_TEXTPREP_TOUPPER; 670 671 zfsvfs->z_use_fuids = USE_FUIDS(zfsvfs->z_version, zfsvfs->z_os); 672 zfsvfs->z_use_sa = USE_SA(zfsvfs->z_version, zfsvfs->z_os); 673 674 uint64_t sa_obj = 0; 675 if (zfsvfs->z_use_sa) { 676 /* should either have both of these objects or none */ 677 error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_SA_ATTRS, 8, 1, 678 &sa_obj); 679 if (error != 0) 680 return (error); 681 682 error = zfs_get_zplprop(os, ZFS_PROP_XATTR, &val); 683 if ((error == 0) && (val == ZFS_XATTR_SA)) 684 zfsvfs->z_xattr_sa = B_TRUE; 685 } 686 687 error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_ROOT_OBJ, 8, 1, 688 &zfsvfs->z_root); 689 if (error != 0) 690 return (error); 691 ASSERT(zfsvfs->z_root != 0); 692 693 error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_UNLINKED_SET, 8, 1, 694 &zfsvfs->z_unlinkedobj); 695 if (error != 0) 696 return (error); 697 698 error = zap_lookup(os, MASTER_NODE_OBJ, 699 zfs_userquota_prop_prefixes[ZFS_PROP_USERQUOTA], 700 8, 1, &zfsvfs->z_userquota_obj); 701 if (error == ENOENT) 702 zfsvfs->z_userquota_obj = 0; 703 else if (error != 0) 704 return (error); 705 706 error = zap_lookup(os, MASTER_NODE_OBJ, 707 zfs_userquota_prop_prefixes[ZFS_PROP_GROUPQUOTA], 708 8, 1, &zfsvfs->z_groupquota_obj); 709 if (error == ENOENT) 710 zfsvfs->z_groupquota_obj = 0; 711 else if (error != 0) 712 return (error); 713 714 error = zap_lookup(os, MASTER_NODE_OBJ, 715 zfs_userquota_prop_prefixes[ZFS_PROP_PROJECTQUOTA], 716 8, 1, &zfsvfs->z_projectquota_obj); 717 if (error == ENOENT) 718 zfsvfs->z_projectquota_obj = 0; 719 else if (error != 0) 720 return (error); 721 722 error = zap_lookup(os, MASTER_NODE_OBJ, 723 zfs_userquota_prop_prefixes[ZFS_PROP_USEROBJQUOTA], 724 8, 1, &zfsvfs->z_userobjquota_obj); 725 if (error == ENOENT) 726 zfsvfs->z_userobjquota_obj = 0; 727 else if (error != 0) 728 return (error); 729 730 error = zap_lookup(os, MASTER_NODE_OBJ, 731 zfs_userquota_prop_prefixes[ZFS_PROP_GROUPOBJQUOTA], 732 8, 1, &zfsvfs->z_groupobjquota_obj); 733 if (error == ENOENT) 734 zfsvfs->z_groupobjquota_obj = 0; 735 else if (error != 0) 736 return (error); 737 738 error = zap_lookup(os, MASTER_NODE_OBJ, 739 zfs_userquota_prop_prefixes[ZFS_PROP_PROJECTOBJQUOTA], 740 8, 1, &zfsvfs->z_projectobjquota_obj); 741 if (error == ENOENT) 742 zfsvfs->z_projectobjquota_obj = 0; 743 else if (error != 0) 744 return (error); 745 746 error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_FUID_TABLES, 8, 1, 747 &zfsvfs->z_fuid_obj); 748 if (error == ENOENT) 749 zfsvfs->z_fuid_obj = 0; 750 else if (error != 0) 751 return (error); 752 753 error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_SHARES_DIR, 8, 1, 754 &zfsvfs->z_shares_dir); 755 if (error == ENOENT) 756 zfsvfs->z_shares_dir = 0; 757 else if (error != 0) 758 return (error); 759 760 error = sa_setup(os, sa_obj, zfs_attr_table, ZPL_END, 761 &zfsvfs->z_attr_table); 762 if (error != 0) 763 return (error); 764 765 if (zfsvfs->z_version >= ZPL_VERSION_SA) 766 sa_register_update_callback(os, zfs_sa_upgrade); 767 768 return (0); 769 } 770 771 int 772 zfsvfs_create(const char *osname, boolean_t readonly, zfsvfs_t **zfvp) 773 { 774 objset_t *os; 775 zfsvfs_t *zfsvfs; 776 int error; 777 boolean_t ro = (readonly || (strchr(osname, '@') != NULL)); 778 779 zfsvfs = kmem_zalloc(sizeof (zfsvfs_t), KM_SLEEP); 780 781 error = dmu_objset_own(osname, DMU_OST_ZFS, ro, B_TRUE, zfsvfs, &os); 782 if (error != 0) { 783 kmem_free(zfsvfs, sizeof (zfsvfs_t)); 784 return (error); 785 } 786 787 error = zfsvfs_create_impl(zfvp, zfsvfs, os); 788 789 return (error); 790 } 791 792 793 /* 794 * Note: zfsvfs is assumed to be malloc'd, and will be freed by this function 795 * on a failure. Do not pass in a statically allocated zfsvfs. 796 */ 797 int 798 zfsvfs_create_impl(zfsvfs_t **zfvp, zfsvfs_t *zfsvfs, objset_t *os) 799 { 800 int error; 801 802 zfsvfs->z_vfs = NULL; 803 zfsvfs->z_sb = NULL; 804 zfsvfs->z_parent = zfsvfs; 805 806 mutex_init(&zfsvfs->z_znodes_lock, NULL, MUTEX_DEFAULT, NULL); 807 mutex_init(&zfsvfs->z_lock, NULL, MUTEX_DEFAULT, NULL); 808 list_create(&zfsvfs->z_all_znodes, sizeof (znode_t), 809 offsetof(znode_t, z_link_node)); 810 ZFS_TEARDOWN_INIT(zfsvfs); 811 rw_init(&zfsvfs->z_teardown_inactive_lock, NULL, RW_DEFAULT, NULL); 812 rw_init(&zfsvfs->z_fuid_lock, NULL, RW_DEFAULT, NULL); 813 814 int size = MIN(1 << (highbit64(zfs_object_mutex_size) - 1), 815 ZFS_OBJ_MTX_MAX); 816 zfsvfs->z_hold_size = size; 817 zfsvfs->z_hold_trees = vmem_zalloc(sizeof (avl_tree_t) * size, 818 KM_SLEEP); 819 zfsvfs->z_hold_locks = vmem_zalloc(sizeof (kmutex_t) * size, KM_SLEEP); 820 for (int i = 0; i != size; i++) { 821 avl_create(&zfsvfs->z_hold_trees[i], zfs_znode_hold_compare, 822 sizeof (znode_hold_t), offsetof(znode_hold_t, zh_node)); 823 mutex_init(&zfsvfs->z_hold_locks[i], NULL, MUTEX_DEFAULT, NULL); 824 } 825 826 error = zfsvfs_init(zfsvfs, os); 827 if (error != 0) { 828 dmu_objset_disown(os, B_TRUE, zfsvfs); 829 *zfvp = NULL; 830 zfsvfs_free(zfsvfs); 831 return (error); 832 } 833 834 zfsvfs->z_drain_task = TASKQID_INVALID; 835 zfsvfs->z_draining = B_FALSE; 836 zfsvfs->z_drain_cancel = B_TRUE; 837 838 *zfvp = zfsvfs; 839 return (0); 840 } 841 842 static int 843 zfsvfs_setup(zfsvfs_t *zfsvfs, boolean_t mounting) 844 { 845 int error; 846 boolean_t readonly = zfs_is_readonly(zfsvfs); 847 848 error = zfs_register_callbacks(zfsvfs->z_vfs); 849 if (error) 850 return (error); 851 852 /* 853 * If we are not mounting (ie: online recv), then we don't 854 * have to worry about replaying the log as we blocked all 855 * operations out since we closed the ZIL. 856 */ 857 if (mounting) { 858 ASSERT3P(zfsvfs->z_kstat.dk_kstats, ==, NULL); 859 error = dataset_kstats_create(&zfsvfs->z_kstat, zfsvfs->z_os); 860 if (error) 861 return (error); 862 zfsvfs->z_log = zil_open(zfsvfs->z_os, zfs_get_data, 863 &zfsvfs->z_kstat.dk_zil_sums); 864 865 /* 866 * During replay we remove the read only flag to 867 * allow replays to succeed. 868 */ 869 if (readonly != 0) { 870 readonly_changed_cb(zfsvfs, B_FALSE); 871 } else { 872 zap_stats_t zs; 873 if (zap_get_stats(zfsvfs->z_os, zfsvfs->z_unlinkedobj, 874 &zs) == 0) { 875 dataset_kstats_update_nunlinks_kstat( 876 &zfsvfs->z_kstat, zs.zs_num_entries); 877 dprintf_ds(zfsvfs->z_os->os_dsl_dataset, 878 "num_entries in unlinked set: %llu", 879 zs.zs_num_entries); 880 } 881 zfs_unlinked_drain(zfsvfs); 882 dsl_dir_t *dd = zfsvfs->z_os->os_dsl_dataset->ds_dir; 883 dd->dd_activity_cancelled = B_FALSE; 884 } 885 886 /* 887 * Parse and replay the intent log. 888 * 889 * Because of ziltest, this must be done after 890 * zfs_unlinked_drain(). (Further note: ziltest 891 * doesn't use readonly mounts, where 892 * zfs_unlinked_drain() isn't called.) This is because 893 * ziltest causes spa_sync() to think it's committed, 894 * but actually it is not, so the intent log contains 895 * many txg's worth of changes. 896 * 897 * In particular, if object N is in the unlinked set in 898 * the last txg to actually sync, then it could be 899 * actually freed in a later txg and then reallocated 900 * in a yet later txg. This would write a "create 901 * object N" record to the intent log. Normally, this 902 * would be fine because the spa_sync() would have 903 * written out the fact that object N is free, before 904 * we could write the "create object N" intent log 905 * record. 906 * 907 * But when we are in ziltest mode, we advance the "open 908 * txg" without actually spa_sync()-ing the changes to 909 * disk. So we would see that object N is still 910 * allocated and in the unlinked set, and there is an 911 * intent log record saying to allocate it. 912 */ 913 if (spa_writeable(dmu_objset_spa(zfsvfs->z_os))) { 914 if (zil_replay_disable) { 915 zil_destroy(zfsvfs->z_log, B_FALSE); 916 } else { 917 zfsvfs->z_replay = B_TRUE; 918 zil_replay(zfsvfs->z_os, zfsvfs, 919 zfs_replay_vector); 920 zfsvfs->z_replay = B_FALSE; 921 } 922 } 923 924 /* restore readonly bit */ 925 if (readonly != 0) 926 readonly_changed_cb(zfsvfs, B_TRUE); 927 } else { 928 ASSERT3P(zfsvfs->z_kstat.dk_kstats, !=, NULL); 929 zfsvfs->z_log = zil_open(zfsvfs->z_os, zfs_get_data, 930 &zfsvfs->z_kstat.dk_zil_sums); 931 } 932 933 /* 934 * Set the objset user_ptr to track its zfsvfs. 935 */ 936 mutex_enter(&zfsvfs->z_os->os_user_ptr_lock); 937 dmu_objset_set_user(zfsvfs->z_os, zfsvfs); 938 mutex_exit(&zfsvfs->z_os->os_user_ptr_lock); 939 940 return (0); 941 } 942 943 void 944 zfsvfs_free(zfsvfs_t *zfsvfs) 945 { 946 int i, size = zfsvfs->z_hold_size; 947 948 zfs_fuid_destroy(zfsvfs); 949 950 mutex_destroy(&zfsvfs->z_znodes_lock); 951 mutex_destroy(&zfsvfs->z_lock); 952 list_destroy(&zfsvfs->z_all_znodes); 953 ZFS_TEARDOWN_DESTROY(zfsvfs); 954 rw_destroy(&zfsvfs->z_teardown_inactive_lock); 955 rw_destroy(&zfsvfs->z_fuid_lock); 956 for (i = 0; i != size; i++) { 957 avl_destroy(&zfsvfs->z_hold_trees[i]); 958 mutex_destroy(&zfsvfs->z_hold_locks[i]); 959 } 960 vmem_free(zfsvfs->z_hold_trees, sizeof (avl_tree_t) * size); 961 vmem_free(zfsvfs->z_hold_locks, sizeof (kmutex_t) * size); 962 zfsvfs_vfs_free(zfsvfs->z_vfs); 963 dataset_kstats_destroy(&zfsvfs->z_kstat); 964 kmem_free(zfsvfs, sizeof (zfsvfs_t)); 965 } 966 967 static void 968 zfs_set_fuid_feature(zfsvfs_t *zfsvfs) 969 { 970 zfsvfs->z_use_fuids = USE_FUIDS(zfsvfs->z_version, zfsvfs->z_os); 971 zfsvfs->z_use_sa = USE_SA(zfsvfs->z_version, zfsvfs->z_os); 972 } 973 974 static void 975 zfs_unregister_callbacks(zfsvfs_t *zfsvfs) 976 { 977 objset_t *os = zfsvfs->z_os; 978 979 if (!dmu_objset_is_snapshot(os)) 980 dsl_prop_unregister_all(dmu_objset_ds(os), zfsvfs); 981 } 982 983 #ifdef HAVE_MLSLABEL 984 /* 985 * Check that the hex label string is appropriate for the dataset being 986 * mounted into the global_zone proper. 987 * 988 * Return an error if the hex label string is not default or 989 * admin_low/admin_high. For admin_low labels, the corresponding 990 * dataset must be readonly. 991 */ 992 int 993 zfs_check_global_label(const char *dsname, const char *hexsl) 994 { 995 if (strcasecmp(hexsl, ZFS_MLSLABEL_DEFAULT) == 0) 996 return (0); 997 if (strcasecmp(hexsl, ADMIN_HIGH) == 0) 998 return (0); 999 if (strcasecmp(hexsl, ADMIN_LOW) == 0) { 1000 /* must be readonly */ 1001 uint64_t rdonly; 1002 1003 if (dsl_prop_get_integer(dsname, 1004 zfs_prop_to_name(ZFS_PROP_READONLY), &rdonly, NULL)) 1005 return (SET_ERROR(EACCES)); 1006 return (rdonly ? 0 : SET_ERROR(EACCES)); 1007 } 1008 return (SET_ERROR(EACCES)); 1009 } 1010 #endif /* HAVE_MLSLABEL */ 1011 1012 static int 1013 zfs_statfs_project(zfsvfs_t *zfsvfs, znode_t *zp, struct kstatfs *statp, 1014 uint32_t bshift) 1015 { 1016 char buf[20 + DMU_OBJACCT_PREFIX_LEN]; 1017 uint64_t offset = DMU_OBJACCT_PREFIX_LEN; 1018 uint64_t quota; 1019 uint64_t used; 1020 int err; 1021 1022 strlcpy(buf, DMU_OBJACCT_PREFIX, DMU_OBJACCT_PREFIX_LEN + 1); 1023 err = zfs_id_to_fuidstr(zfsvfs, NULL, zp->z_projid, buf + offset, 1024 sizeof (buf) - offset, B_FALSE); 1025 if (err) 1026 return (err); 1027 1028 if (zfsvfs->z_projectquota_obj == 0) 1029 goto objs; 1030 1031 err = zap_lookup(zfsvfs->z_os, zfsvfs->z_projectquota_obj, 1032 buf + offset, 8, 1, "a); 1033 if (err == ENOENT) 1034 goto objs; 1035 else if (err) 1036 return (err); 1037 1038 err = zap_lookup(zfsvfs->z_os, DMU_PROJECTUSED_OBJECT, 1039 buf + offset, 8, 1, &used); 1040 if (unlikely(err == ENOENT)) { 1041 uint32_t blksize; 1042 u_longlong_t nblocks; 1043 1044 /* 1045 * Quota accounting is async, so it is possible race case. 1046 * There is at least one object with the given project ID. 1047 */ 1048 sa_object_size(zp->z_sa_hdl, &blksize, &nblocks); 1049 if (unlikely(zp->z_blksz == 0)) 1050 blksize = zfsvfs->z_max_blksz; 1051 1052 used = blksize * nblocks; 1053 } else if (err) { 1054 return (err); 1055 } 1056 1057 statp->f_blocks = quota >> bshift; 1058 statp->f_bfree = (quota > used) ? ((quota - used) >> bshift) : 0; 1059 statp->f_bavail = statp->f_bfree; 1060 1061 objs: 1062 if (zfsvfs->z_projectobjquota_obj == 0) 1063 return (0); 1064 1065 err = zap_lookup(zfsvfs->z_os, zfsvfs->z_projectobjquota_obj, 1066 buf + offset, 8, 1, "a); 1067 if (err == ENOENT) 1068 return (0); 1069 else if (err) 1070 return (err); 1071 1072 err = zap_lookup(zfsvfs->z_os, DMU_PROJECTUSED_OBJECT, 1073 buf, 8, 1, &used); 1074 if (unlikely(err == ENOENT)) { 1075 /* 1076 * Quota accounting is async, so it is possible race case. 1077 * There is at least one object with the given project ID. 1078 */ 1079 used = 1; 1080 } else if (err) { 1081 return (err); 1082 } 1083 1084 statp->f_files = quota; 1085 statp->f_ffree = (quota > used) ? (quota - used) : 0; 1086 1087 return (0); 1088 } 1089 1090 int 1091 zfs_statvfs(struct inode *ip, struct kstatfs *statp) 1092 { 1093 zfsvfs_t *zfsvfs = ITOZSB(ip); 1094 uint64_t refdbytes, availbytes, usedobjs, availobjs; 1095 int err = 0; 1096 1097 if ((err = zfs_enter(zfsvfs, FTAG)) != 0) 1098 return (err); 1099 1100 dmu_objset_space(zfsvfs->z_os, 1101 &refdbytes, &availbytes, &usedobjs, &availobjs); 1102 1103 uint64_t fsid = dmu_objset_fsid_guid(zfsvfs->z_os); 1104 /* 1105 * The underlying storage pool actually uses multiple block 1106 * size. Under Solaris frsize (fragment size) is reported as 1107 * the smallest block size we support, and bsize (block size) 1108 * as the filesystem's maximum block size. Unfortunately, 1109 * under Linux the fragment size and block size are often used 1110 * interchangeably. Thus we are forced to report both of them 1111 * as the filesystem's maximum block size. 1112 */ 1113 statp->f_frsize = zfsvfs->z_max_blksz; 1114 statp->f_bsize = zfsvfs->z_max_blksz; 1115 uint32_t bshift = fls(statp->f_bsize) - 1; 1116 1117 /* 1118 * The following report "total" blocks of various kinds in 1119 * the file system, but reported in terms of f_bsize - the 1120 * "preferred" size. 1121 */ 1122 1123 /* Round up so we never have a filesystem using 0 blocks. */ 1124 refdbytes = P2ROUNDUP(refdbytes, statp->f_bsize); 1125 statp->f_blocks = (refdbytes + availbytes) >> bshift; 1126 statp->f_bfree = availbytes >> bshift; 1127 statp->f_bavail = statp->f_bfree; /* no root reservation */ 1128 1129 /* 1130 * statvfs() should really be called statufs(), because it assumes 1131 * static metadata. ZFS doesn't preallocate files, so the best 1132 * we can do is report the max that could possibly fit in f_files, 1133 * and that minus the number actually used in f_ffree. 1134 * For f_ffree, report the smaller of the number of objects available 1135 * and the number of blocks (each object will take at least a block). 1136 */ 1137 statp->f_ffree = MIN(availobjs, availbytes >> DNODE_SHIFT); 1138 statp->f_files = statp->f_ffree + usedobjs; 1139 statp->f_fsid.val[0] = (uint32_t)fsid; 1140 statp->f_fsid.val[1] = (uint32_t)(fsid >> 32); 1141 statp->f_type = ZFS_SUPER_MAGIC; 1142 statp->f_namelen = MAXNAMELEN - 1; 1143 1144 /* 1145 * We have all of 40 characters to stuff a string here. 1146 * Is there anything useful we could/should provide? 1147 */ 1148 memset(statp->f_spare, 0, sizeof (statp->f_spare)); 1149 1150 if (dmu_objset_projectquota_enabled(zfsvfs->z_os) && 1151 dmu_objset_projectquota_present(zfsvfs->z_os)) { 1152 znode_t *zp = ITOZ(ip); 1153 1154 if (zp->z_pflags & ZFS_PROJINHERIT && zp->z_projid && 1155 zpl_is_valid_projid(zp->z_projid)) 1156 err = zfs_statfs_project(zfsvfs, zp, statp, bshift); 1157 } 1158 1159 zfs_exit(zfsvfs, FTAG); 1160 return (err); 1161 } 1162 1163 static int 1164 zfs_root(zfsvfs_t *zfsvfs, struct inode **ipp) 1165 { 1166 znode_t *rootzp; 1167 int error; 1168 1169 if ((error = zfs_enter(zfsvfs, FTAG)) != 0) 1170 return (error); 1171 1172 error = zfs_zget(zfsvfs, zfsvfs->z_root, &rootzp); 1173 if (error == 0) 1174 *ipp = ZTOI(rootzp); 1175 1176 zfs_exit(zfsvfs, FTAG); 1177 return (error); 1178 } 1179 1180 /* 1181 * Linux kernels older than 3.1 do not support a per-filesystem shrinker. 1182 * To accommodate this we must improvise and manually walk the list of znodes 1183 * attempting to prune dentries in order to be able to drop the inodes. 1184 * 1185 * To avoid scanning the same znodes multiple times they are always rotated 1186 * to the end of the z_all_znodes list. New znodes are inserted at the 1187 * end of the list so we're always scanning the oldest znodes first. 1188 */ 1189 static int 1190 zfs_prune_aliases(zfsvfs_t *zfsvfs, unsigned long nr_to_scan) 1191 { 1192 znode_t **zp_array, *zp; 1193 int max_array = MIN(nr_to_scan, PAGE_SIZE * 8 / sizeof (znode_t *)); 1194 int objects = 0; 1195 int i = 0, j = 0; 1196 1197 zp_array = vmem_zalloc(max_array * sizeof (znode_t *), KM_SLEEP); 1198 1199 mutex_enter(&zfsvfs->z_znodes_lock); 1200 while ((zp = list_head(&zfsvfs->z_all_znodes)) != NULL) { 1201 1202 if ((i++ > nr_to_scan) || (j >= max_array)) 1203 break; 1204 1205 ASSERT(list_link_active(&zp->z_link_node)); 1206 list_remove(&zfsvfs->z_all_znodes, zp); 1207 list_insert_tail(&zfsvfs->z_all_znodes, zp); 1208 1209 /* Skip active znodes and .zfs entries */ 1210 if (MUTEX_HELD(&zp->z_lock) || zp->z_is_ctldir) 1211 continue; 1212 1213 if (igrab(ZTOI(zp)) == NULL) 1214 continue; 1215 1216 zp_array[j] = zp; 1217 j++; 1218 } 1219 mutex_exit(&zfsvfs->z_znodes_lock); 1220 1221 for (i = 0; i < j; i++) { 1222 zp = zp_array[i]; 1223 1224 ASSERT3P(zp, !=, NULL); 1225 d_prune_aliases(ZTOI(zp)); 1226 1227 if (atomic_read(&ZTOI(zp)->i_count) == 1) 1228 objects++; 1229 1230 zrele(zp); 1231 } 1232 1233 vmem_free(zp_array, max_array * sizeof (znode_t *)); 1234 1235 return (objects); 1236 } 1237 1238 /* 1239 * The ARC has requested that the filesystem drop entries from the dentry 1240 * and inode caches. This can occur when the ARC needs to free meta data 1241 * blocks but can't because they are all pinned by entries in these caches. 1242 */ 1243 #if defined(HAVE_SUPER_BLOCK_S_SHRINK) 1244 #define S_SHRINK(sb) (&(sb)->s_shrink) 1245 #elif defined(HAVE_SUPER_BLOCK_S_SHRINK_PTR) 1246 #define S_SHRINK(sb) ((sb)->s_shrink) 1247 #endif 1248 1249 int 1250 zfs_prune(struct super_block *sb, unsigned long nr_to_scan, int *objects) 1251 { 1252 zfsvfs_t *zfsvfs = sb->s_fs_info; 1253 int error = 0; 1254 struct shrinker *shrinker = S_SHRINK(sb); 1255 struct shrink_control sc = { 1256 .nr_to_scan = nr_to_scan, 1257 .gfp_mask = GFP_KERNEL, 1258 }; 1259 1260 if ((error = zfs_enter(zfsvfs, FTAG)) != 0) 1261 return (error); 1262 1263 #if defined(HAVE_SPLIT_SHRINKER_CALLBACK) && \ 1264 defined(SHRINK_CONTROL_HAS_NID) && \ 1265 defined(SHRINKER_NUMA_AWARE) 1266 if (shrinker->flags & SHRINKER_NUMA_AWARE) { 1267 *objects = 0; 1268 for_each_online_node(sc.nid) { 1269 *objects += (*shrinker->scan_objects)(shrinker, &sc); 1270 /* 1271 * reset sc.nr_to_scan, modified by 1272 * scan_objects == super_cache_scan 1273 */ 1274 sc.nr_to_scan = nr_to_scan; 1275 } 1276 } else { 1277 *objects = (*shrinker->scan_objects)(shrinker, &sc); 1278 } 1279 1280 #elif defined(HAVE_SPLIT_SHRINKER_CALLBACK) 1281 *objects = (*shrinker->scan_objects)(shrinker, &sc); 1282 #elif defined(HAVE_SINGLE_SHRINKER_CALLBACK) 1283 *objects = (*shrinker->shrink)(shrinker, &sc); 1284 #elif defined(HAVE_D_PRUNE_ALIASES) 1285 #define D_PRUNE_ALIASES_IS_DEFAULT 1286 *objects = zfs_prune_aliases(zfsvfs, nr_to_scan); 1287 #else 1288 #error "No available dentry and inode cache pruning mechanism." 1289 #endif 1290 1291 #if defined(HAVE_D_PRUNE_ALIASES) && !defined(D_PRUNE_ALIASES_IS_DEFAULT) 1292 #undef D_PRUNE_ALIASES_IS_DEFAULT 1293 /* 1294 * Fall back to zfs_prune_aliases if the kernel's per-superblock 1295 * shrinker couldn't free anything, possibly due to the inodes being 1296 * allocated in a different memcg. 1297 */ 1298 if (*objects == 0) 1299 *objects = zfs_prune_aliases(zfsvfs, nr_to_scan); 1300 #endif 1301 1302 zfs_exit(zfsvfs, FTAG); 1303 1304 dprintf_ds(zfsvfs->z_os->os_dsl_dataset, 1305 "pruning, nr_to_scan=%lu objects=%d error=%d\n", 1306 nr_to_scan, *objects, error); 1307 1308 return (error); 1309 } 1310 1311 /* 1312 * Teardown the zfsvfs_t. 1313 * 1314 * Note, if 'unmounting' is FALSE, we return with the 'z_teardown_lock' 1315 * and 'z_teardown_inactive_lock' held. 1316 */ 1317 static int 1318 zfsvfs_teardown(zfsvfs_t *zfsvfs, boolean_t unmounting) 1319 { 1320 znode_t *zp; 1321 1322 zfs_unlinked_drain_stop_wait(zfsvfs); 1323 1324 /* 1325 * If someone has not already unmounted this file system, 1326 * drain the zrele_taskq to ensure all active references to the 1327 * zfsvfs_t have been handled only then can it be safely destroyed. 1328 */ 1329 if (zfsvfs->z_os) { 1330 /* 1331 * If we're unmounting we have to wait for the list to 1332 * drain completely. 1333 * 1334 * If we're not unmounting there's no guarantee the list 1335 * will drain completely, but iputs run from the taskq 1336 * may add the parents of dir-based xattrs to the taskq 1337 * so we want to wait for these. 1338 * 1339 * We can safely check z_all_znodes for being empty because the 1340 * VFS has already blocked operations which add to it. 1341 */ 1342 int round = 0; 1343 while (!list_is_empty(&zfsvfs->z_all_znodes)) { 1344 taskq_wait_outstanding(dsl_pool_zrele_taskq( 1345 dmu_objset_pool(zfsvfs->z_os)), 0); 1346 if (++round > 1 && !unmounting) 1347 break; 1348 } 1349 } 1350 1351 ZFS_TEARDOWN_ENTER_WRITE(zfsvfs, FTAG); 1352 1353 if (!unmounting) { 1354 /* 1355 * We purge the parent filesystem's super block as the 1356 * parent filesystem and all of its snapshots have their 1357 * inode's super block set to the parent's filesystem's 1358 * super block. Note, 'z_parent' is self referential 1359 * for non-snapshots. 1360 */ 1361 shrink_dcache_sb(zfsvfs->z_parent->z_sb); 1362 } 1363 1364 /* 1365 * Close the zil. NB: Can't close the zil while zfs_inactive 1366 * threads are blocked as zil_close can call zfs_inactive. 1367 */ 1368 if (zfsvfs->z_log) { 1369 zil_close(zfsvfs->z_log); 1370 zfsvfs->z_log = NULL; 1371 } 1372 1373 rw_enter(&zfsvfs->z_teardown_inactive_lock, RW_WRITER); 1374 1375 /* 1376 * If we are not unmounting (ie: online recv) and someone already 1377 * unmounted this file system while we were doing the switcheroo, 1378 * or a reopen of z_os failed then just bail out now. 1379 */ 1380 if (!unmounting && (zfsvfs->z_unmounted || zfsvfs->z_os == NULL)) { 1381 rw_exit(&zfsvfs->z_teardown_inactive_lock); 1382 ZFS_TEARDOWN_EXIT(zfsvfs, FTAG); 1383 return (SET_ERROR(EIO)); 1384 } 1385 1386 /* 1387 * At this point there are no VFS ops active, and any new VFS ops 1388 * will fail with EIO since we have z_teardown_lock for writer (only 1389 * relevant for forced unmount). 1390 * 1391 * Release all holds on dbufs. We also grab an extra reference to all 1392 * the remaining inodes so that the kernel does not attempt to free 1393 * any inodes of a suspended fs. This can cause deadlocks since the 1394 * zfs_resume_fs() process may involve starting threads, which might 1395 * attempt to free unreferenced inodes to free up memory for the new 1396 * thread. 1397 */ 1398 if (!unmounting) { 1399 mutex_enter(&zfsvfs->z_znodes_lock); 1400 for (zp = list_head(&zfsvfs->z_all_znodes); zp != NULL; 1401 zp = list_next(&zfsvfs->z_all_znodes, zp)) { 1402 if (zp->z_sa_hdl) 1403 zfs_znode_dmu_fini(zp); 1404 if (igrab(ZTOI(zp)) != NULL) 1405 zp->z_suspended = B_TRUE; 1406 1407 } 1408 mutex_exit(&zfsvfs->z_znodes_lock); 1409 } 1410 1411 /* 1412 * If we are unmounting, set the unmounted flag and let new VFS ops 1413 * unblock. zfs_inactive will have the unmounted behavior, and all 1414 * other VFS ops will fail with EIO. 1415 */ 1416 if (unmounting) { 1417 zfsvfs->z_unmounted = B_TRUE; 1418 rw_exit(&zfsvfs->z_teardown_inactive_lock); 1419 ZFS_TEARDOWN_EXIT(zfsvfs, FTAG); 1420 } 1421 1422 /* 1423 * z_os will be NULL if there was an error in attempting to reopen 1424 * zfsvfs, so just return as the properties had already been 1425 * 1426 * unregistered and cached data had been evicted before. 1427 */ 1428 if (zfsvfs->z_os == NULL) 1429 return (0); 1430 1431 /* 1432 * Unregister properties. 1433 */ 1434 zfs_unregister_callbacks(zfsvfs); 1435 1436 /* 1437 * Evict cached data. We must write out any dirty data before 1438 * disowning the dataset. 1439 */ 1440 objset_t *os = zfsvfs->z_os; 1441 boolean_t os_dirty = B_FALSE; 1442 for (int t = 0; t < TXG_SIZE; t++) { 1443 if (dmu_objset_is_dirty(os, t)) { 1444 os_dirty = B_TRUE; 1445 break; 1446 } 1447 } 1448 if (!zfs_is_readonly(zfsvfs) && os_dirty) { 1449 txg_wait_synced(dmu_objset_pool(zfsvfs->z_os), 0); 1450 } 1451 dmu_objset_evict_dbufs(zfsvfs->z_os); 1452 dsl_dir_t *dd = os->os_dsl_dataset->ds_dir; 1453 dsl_dir_cancel_waiters(dd); 1454 1455 return (0); 1456 } 1457 1458 #if defined(HAVE_SUPER_SETUP_BDI_NAME) 1459 atomic_long_t zfs_bdi_seq = ATOMIC_LONG_INIT(0); 1460 #endif 1461 1462 int 1463 zfs_domount(struct super_block *sb, zfs_mnt_t *zm, int silent) 1464 { 1465 const char *osname = zm->mnt_osname; 1466 struct inode *root_inode = NULL; 1467 uint64_t recordsize; 1468 int error = 0; 1469 zfsvfs_t *zfsvfs = NULL; 1470 vfs_t *vfs = NULL; 1471 int canwrite; 1472 int dataset_visible_zone; 1473 1474 ASSERT(zm); 1475 ASSERT(osname); 1476 1477 dataset_visible_zone = zone_dataset_visible(osname, &canwrite); 1478 1479 /* 1480 * Refuse to mount a filesystem if we are in a namespace and the 1481 * dataset is not visible or writable in that namespace. 1482 */ 1483 if (!INGLOBALZONE(curproc) && 1484 (!dataset_visible_zone || !canwrite)) { 1485 return (SET_ERROR(EPERM)); 1486 } 1487 1488 error = zfsvfs_parse_options(zm->mnt_data, &vfs); 1489 if (error) 1490 return (error); 1491 1492 /* 1493 * If a non-writable filesystem is being mounted without the 1494 * read-only flag, pretend it was set, as done for snapshots. 1495 */ 1496 if (!canwrite) 1497 vfs->vfs_readonly = B_TRUE; 1498 1499 error = zfsvfs_create(osname, vfs->vfs_readonly, &zfsvfs); 1500 if (error) { 1501 zfsvfs_vfs_free(vfs); 1502 goto out; 1503 } 1504 1505 if ((error = dsl_prop_get_integer(osname, "recordsize", 1506 &recordsize, NULL))) { 1507 zfsvfs_vfs_free(vfs); 1508 goto out; 1509 } 1510 1511 vfs->vfs_data = zfsvfs; 1512 zfsvfs->z_vfs = vfs; 1513 zfsvfs->z_sb = sb; 1514 sb->s_fs_info = zfsvfs; 1515 sb->s_magic = ZFS_SUPER_MAGIC; 1516 sb->s_maxbytes = MAX_LFS_FILESIZE; 1517 sb->s_time_gran = 1; 1518 sb->s_blocksize = recordsize; 1519 sb->s_blocksize_bits = ilog2(recordsize); 1520 1521 error = -zpl_bdi_setup(sb, "zfs"); 1522 if (error) 1523 goto out; 1524 1525 sb->s_bdi->ra_pages = 0; 1526 1527 /* Set callback operations for the file system. */ 1528 sb->s_op = &zpl_super_operations; 1529 sb->s_xattr = zpl_xattr_handlers; 1530 sb->s_export_op = &zpl_export_operations; 1531 1532 /* Set features for file system. */ 1533 zfs_set_fuid_feature(zfsvfs); 1534 1535 if (dmu_objset_is_snapshot(zfsvfs->z_os)) { 1536 uint64_t pval; 1537 1538 atime_changed_cb(zfsvfs, B_FALSE); 1539 readonly_changed_cb(zfsvfs, B_TRUE); 1540 if ((error = dsl_prop_get_integer(osname, 1541 "xattr", &pval, NULL))) 1542 goto out; 1543 xattr_changed_cb(zfsvfs, pval); 1544 if ((error = dsl_prop_get_integer(osname, 1545 "acltype", &pval, NULL))) 1546 goto out; 1547 acltype_changed_cb(zfsvfs, pval); 1548 zfsvfs->z_issnap = B_TRUE; 1549 zfsvfs->z_os->os_sync = ZFS_SYNC_DISABLED; 1550 zfsvfs->z_snap_defer_time = jiffies; 1551 1552 mutex_enter(&zfsvfs->z_os->os_user_ptr_lock); 1553 dmu_objset_set_user(zfsvfs->z_os, zfsvfs); 1554 mutex_exit(&zfsvfs->z_os->os_user_ptr_lock); 1555 } else { 1556 if ((error = zfsvfs_setup(zfsvfs, B_TRUE))) 1557 goto out; 1558 } 1559 1560 /* Allocate a root inode for the filesystem. */ 1561 error = zfs_root(zfsvfs, &root_inode); 1562 if (error) { 1563 (void) zfs_umount(sb); 1564 zfsvfs = NULL; /* avoid double-free; first in zfs_umount */ 1565 goto out; 1566 } 1567 1568 /* Allocate a root dentry for the filesystem */ 1569 sb->s_root = d_make_root(root_inode); 1570 if (sb->s_root == NULL) { 1571 (void) zfs_umount(sb); 1572 zfsvfs = NULL; /* avoid double-free; first in zfs_umount */ 1573 error = SET_ERROR(ENOMEM); 1574 goto out; 1575 } 1576 1577 if (!zfsvfs->z_issnap) 1578 zfsctl_create(zfsvfs); 1579 1580 zfsvfs->z_arc_prune = arc_add_prune_callback(zpl_prune_sb, sb); 1581 out: 1582 if (error) { 1583 if (zfsvfs != NULL) { 1584 dmu_objset_disown(zfsvfs->z_os, B_TRUE, zfsvfs); 1585 zfsvfs_free(zfsvfs); 1586 } 1587 /* 1588 * make sure we don't have dangling sb->s_fs_info which 1589 * zfs_preumount will use. 1590 */ 1591 sb->s_fs_info = NULL; 1592 } 1593 1594 return (error); 1595 } 1596 1597 /* 1598 * Called when an unmount is requested and certain sanity checks have 1599 * already passed. At this point no dentries or inodes have been reclaimed 1600 * from their respective caches. We drop the extra reference on the .zfs 1601 * control directory to allow everything to be reclaimed. All snapshots 1602 * must already have been unmounted to reach this point. 1603 */ 1604 void 1605 zfs_preumount(struct super_block *sb) 1606 { 1607 zfsvfs_t *zfsvfs = sb->s_fs_info; 1608 1609 /* zfsvfs is NULL when zfs_domount fails during mount */ 1610 if (zfsvfs) { 1611 zfs_unlinked_drain_stop_wait(zfsvfs); 1612 zfsctl_destroy(sb->s_fs_info); 1613 /* 1614 * Wait for zrele_async before entering evict_inodes in 1615 * generic_shutdown_super. The reason we must finish before 1616 * evict_inodes is when lazytime is on, or when zfs_purgedir 1617 * calls zfs_zget, zrele would bump i_count from 0 to 1. This 1618 * would race with the i_count check in evict_inodes. This means 1619 * it could destroy the inode while we are still using it. 1620 * 1621 * We wait for two passes. xattr directories in the first pass 1622 * may add xattr entries in zfs_purgedir, so in the second pass 1623 * we wait for them. We don't use taskq_wait here because it is 1624 * a pool wide taskq. Other mounted filesystems can constantly 1625 * do zrele_async and there's no guarantee when taskq will be 1626 * empty. 1627 */ 1628 taskq_wait_outstanding(dsl_pool_zrele_taskq( 1629 dmu_objset_pool(zfsvfs->z_os)), 0); 1630 taskq_wait_outstanding(dsl_pool_zrele_taskq( 1631 dmu_objset_pool(zfsvfs->z_os)), 0); 1632 } 1633 } 1634 1635 /* 1636 * Called once all other unmount released tear down has occurred. 1637 * It is our responsibility to release any remaining infrastructure. 1638 */ 1639 int 1640 zfs_umount(struct super_block *sb) 1641 { 1642 zfsvfs_t *zfsvfs = sb->s_fs_info; 1643 objset_t *os; 1644 1645 if (zfsvfs->z_arc_prune != NULL) 1646 arc_remove_prune_callback(zfsvfs->z_arc_prune); 1647 VERIFY(zfsvfs_teardown(zfsvfs, B_TRUE) == 0); 1648 os = zfsvfs->z_os; 1649 zpl_bdi_destroy(sb); 1650 1651 /* 1652 * z_os will be NULL if there was an error in 1653 * attempting to reopen zfsvfs. 1654 */ 1655 if (os != NULL) { 1656 /* 1657 * Unset the objset user_ptr. 1658 */ 1659 mutex_enter(&os->os_user_ptr_lock); 1660 dmu_objset_set_user(os, NULL); 1661 mutex_exit(&os->os_user_ptr_lock); 1662 1663 /* 1664 * Finally release the objset 1665 */ 1666 dmu_objset_disown(os, B_TRUE, zfsvfs); 1667 } 1668 1669 zfsvfs_free(zfsvfs); 1670 sb->s_fs_info = NULL; 1671 return (0); 1672 } 1673 1674 int 1675 zfs_remount(struct super_block *sb, int *flags, zfs_mnt_t *zm) 1676 { 1677 zfsvfs_t *zfsvfs = sb->s_fs_info; 1678 vfs_t *vfsp; 1679 boolean_t issnap = dmu_objset_is_snapshot(zfsvfs->z_os); 1680 int error; 1681 1682 if ((issnap || !spa_writeable(dmu_objset_spa(zfsvfs->z_os))) && 1683 !(*flags & SB_RDONLY)) { 1684 *flags |= SB_RDONLY; 1685 return (EROFS); 1686 } 1687 1688 error = zfsvfs_parse_options(zm->mnt_data, &vfsp); 1689 if (error) 1690 return (error); 1691 1692 if (!zfs_is_readonly(zfsvfs) && (*flags & SB_RDONLY)) 1693 txg_wait_synced(dmu_objset_pool(zfsvfs->z_os), 0); 1694 1695 zfs_unregister_callbacks(zfsvfs); 1696 zfsvfs_vfs_free(zfsvfs->z_vfs); 1697 1698 vfsp->vfs_data = zfsvfs; 1699 zfsvfs->z_vfs = vfsp; 1700 if (!issnap) 1701 (void) zfs_register_callbacks(vfsp); 1702 1703 return (error); 1704 } 1705 1706 int 1707 zfs_vget(struct super_block *sb, struct inode **ipp, fid_t *fidp) 1708 { 1709 zfsvfs_t *zfsvfs = sb->s_fs_info; 1710 znode_t *zp; 1711 uint64_t object = 0; 1712 uint64_t fid_gen = 0; 1713 uint64_t gen_mask; 1714 uint64_t zp_gen; 1715 int i, err; 1716 1717 *ipp = NULL; 1718 1719 if (fidp->fid_len == SHORT_FID_LEN || fidp->fid_len == LONG_FID_LEN) { 1720 zfid_short_t *zfid = (zfid_short_t *)fidp; 1721 1722 for (i = 0; i < sizeof (zfid->zf_object); i++) 1723 object |= ((uint64_t)zfid->zf_object[i]) << (8 * i); 1724 1725 for (i = 0; i < sizeof (zfid->zf_gen); i++) 1726 fid_gen |= ((uint64_t)zfid->zf_gen[i]) << (8 * i); 1727 } else { 1728 return (SET_ERROR(EINVAL)); 1729 } 1730 1731 /* LONG_FID_LEN means snapdirs */ 1732 if (fidp->fid_len == LONG_FID_LEN) { 1733 zfid_long_t *zlfid = (zfid_long_t *)fidp; 1734 uint64_t objsetid = 0; 1735 uint64_t setgen = 0; 1736 1737 for (i = 0; i < sizeof (zlfid->zf_setid); i++) 1738 objsetid |= ((uint64_t)zlfid->zf_setid[i]) << (8 * i); 1739 1740 for (i = 0; i < sizeof (zlfid->zf_setgen); i++) 1741 setgen |= ((uint64_t)zlfid->zf_setgen[i]) << (8 * i); 1742 1743 if (objsetid != ZFSCTL_INO_SNAPDIRS - object) { 1744 dprintf("snapdir fid: objsetid (%llu) != " 1745 "ZFSCTL_INO_SNAPDIRS (%llu) - object (%llu)\n", 1746 objsetid, ZFSCTL_INO_SNAPDIRS, object); 1747 1748 return (SET_ERROR(EINVAL)); 1749 } 1750 1751 if (fid_gen > 1 || setgen != 0) { 1752 dprintf("snapdir fid: fid_gen (%llu) and setgen " 1753 "(%llu)\n", fid_gen, setgen); 1754 return (SET_ERROR(EINVAL)); 1755 } 1756 1757 return (zfsctl_snapdir_vget(sb, objsetid, fid_gen, ipp)); 1758 } 1759 1760 if ((err = zfs_enter(zfsvfs, FTAG)) != 0) 1761 return (err); 1762 /* A zero fid_gen means we are in the .zfs control directories */ 1763 if (fid_gen == 0 && 1764 (object == ZFSCTL_INO_ROOT || object == ZFSCTL_INO_SNAPDIR)) { 1765 *ipp = zfsvfs->z_ctldir; 1766 ASSERT(*ipp != NULL); 1767 if (object == ZFSCTL_INO_SNAPDIR) { 1768 VERIFY(zfsctl_root_lookup(*ipp, "snapshot", ipp, 1769 0, kcred, NULL, NULL) == 0); 1770 } else { 1771 /* 1772 * Must have an existing ref, so igrab() 1773 * cannot return NULL 1774 */ 1775 VERIFY3P(igrab(*ipp), !=, NULL); 1776 } 1777 zfs_exit(zfsvfs, FTAG); 1778 return (0); 1779 } 1780 1781 gen_mask = -1ULL >> (64 - 8 * i); 1782 1783 dprintf("getting %llu [%llu mask %llx]\n", object, fid_gen, gen_mask); 1784 if ((err = zfs_zget(zfsvfs, object, &zp))) { 1785 zfs_exit(zfsvfs, FTAG); 1786 return (err); 1787 } 1788 1789 /* Don't export xattr stuff */ 1790 if (zp->z_pflags & ZFS_XATTR) { 1791 zrele(zp); 1792 zfs_exit(zfsvfs, FTAG); 1793 return (SET_ERROR(ENOENT)); 1794 } 1795 1796 (void) sa_lookup(zp->z_sa_hdl, SA_ZPL_GEN(zfsvfs), &zp_gen, 1797 sizeof (uint64_t)); 1798 zp_gen = zp_gen & gen_mask; 1799 if (zp_gen == 0) 1800 zp_gen = 1; 1801 if ((fid_gen == 0) && (zfsvfs->z_root == object)) 1802 fid_gen = zp_gen; 1803 if (zp->z_unlinked || zp_gen != fid_gen) { 1804 dprintf("znode gen (%llu) != fid gen (%llu)\n", zp_gen, 1805 fid_gen); 1806 zrele(zp); 1807 zfs_exit(zfsvfs, FTAG); 1808 return (SET_ERROR(ENOENT)); 1809 } 1810 1811 *ipp = ZTOI(zp); 1812 if (*ipp) 1813 zfs_znode_update_vfs(ITOZ(*ipp)); 1814 1815 zfs_exit(zfsvfs, FTAG); 1816 return (0); 1817 } 1818 1819 /* 1820 * Block out VFS ops and close zfsvfs_t 1821 * 1822 * Note, if successful, then we return with the 'z_teardown_lock' and 1823 * 'z_teardown_inactive_lock' write held. We leave ownership of the underlying 1824 * dataset and objset intact so that they can be atomically handed off during 1825 * a subsequent rollback or recv operation and the resume thereafter. 1826 */ 1827 int 1828 zfs_suspend_fs(zfsvfs_t *zfsvfs) 1829 { 1830 int error; 1831 1832 if ((error = zfsvfs_teardown(zfsvfs, B_FALSE)) != 0) 1833 return (error); 1834 1835 return (0); 1836 } 1837 1838 /* 1839 * Rebuild SA and release VOPs. Note that ownership of the underlying dataset 1840 * is an invariant across any of the operations that can be performed while the 1841 * filesystem was suspended. Whether it succeeded or failed, the preconditions 1842 * are the same: the relevant objset and associated dataset are owned by 1843 * zfsvfs, held, and long held on entry. 1844 */ 1845 int 1846 zfs_resume_fs(zfsvfs_t *zfsvfs, dsl_dataset_t *ds) 1847 { 1848 int err, err2; 1849 znode_t *zp; 1850 1851 ASSERT(ZFS_TEARDOWN_WRITE_HELD(zfsvfs)); 1852 ASSERT(RW_WRITE_HELD(&zfsvfs->z_teardown_inactive_lock)); 1853 1854 /* 1855 * We already own this, so just update the objset_t, as the one we 1856 * had before may have been evicted. 1857 */ 1858 objset_t *os; 1859 VERIFY3P(ds->ds_owner, ==, zfsvfs); 1860 VERIFY(dsl_dataset_long_held(ds)); 1861 dsl_pool_t *dp = spa_get_dsl(dsl_dataset_get_spa(ds)); 1862 dsl_pool_config_enter(dp, FTAG); 1863 VERIFY0(dmu_objset_from_ds(ds, &os)); 1864 dsl_pool_config_exit(dp, FTAG); 1865 1866 err = zfsvfs_init(zfsvfs, os); 1867 if (err != 0) 1868 goto bail; 1869 1870 ds->ds_dir->dd_activity_cancelled = B_FALSE; 1871 VERIFY(zfsvfs_setup(zfsvfs, B_FALSE) == 0); 1872 1873 zfs_set_fuid_feature(zfsvfs); 1874 zfsvfs->z_rollback_time = jiffies; 1875 1876 /* 1877 * Attempt to re-establish all the active inodes with their 1878 * dbufs. If a zfs_rezget() fails, then we unhash the inode 1879 * and mark it stale. This prevents a collision if a new 1880 * inode/object is created which must use the same inode 1881 * number. The stale inode will be be released when the 1882 * VFS prunes the dentry holding the remaining references 1883 * on the stale inode. 1884 */ 1885 mutex_enter(&zfsvfs->z_znodes_lock); 1886 for (zp = list_head(&zfsvfs->z_all_znodes); zp; 1887 zp = list_next(&zfsvfs->z_all_znodes, zp)) { 1888 err2 = zfs_rezget(zp); 1889 if (err2) { 1890 zpl_d_drop_aliases(ZTOI(zp)); 1891 remove_inode_hash(ZTOI(zp)); 1892 } 1893 1894 /* see comment in zfs_suspend_fs() */ 1895 if (zp->z_suspended) { 1896 zfs_zrele_async(zp); 1897 zp->z_suspended = B_FALSE; 1898 } 1899 } 1900 mutex_exit(&zfsvfs->z_znodes_lock); 1901 1902 if (!zfs_is_readonly(zfsvfs) && !zfsvfs->z_unmounted) { 1903 /* 1904 * zfs_suspend_fs() could have interrupted freeing 1905 * of dnodes. We need to restart this freeing so 1906 * that we don't "leak" the space. 1907 */ 1908 zfs_unlinked_drain(zfsvfs); 1909 } 1910 1911 /* 1912 * Most of the time zfs_suspend_fs is used for changing the contents 1913 * of the underlying dataset. ZFS rollback and receive operations 1914 * might create files for which negative dentries are present in 1915 * the cache. Since walking the dcache would require a lot of GPL-only 1916 * code duplication, it's much easier on these rather rare occasions 1917 * just to flush the whole dcache for the given dataset/filesystem. 1918 */ 1919 shrink_dcache_sb(zfsvfs->z_sb); 1920 1921 bail: 1922 if (err != 0) 1923 zfsvfs->z_unmounted = B_TRUE; 1924 1925 /* release the VFS ops */ 1926 rw_exit(&zfsvfs->z_teardown_inactive_lock); 1927 ZFS_TEARDOWN_EXIT(zfsvfs, FTAG); 1928 1929 if (err != 0) { 1930 /* 1931 * Since we couldn't setup the sa framework, try to force 1932 * unmount this file system. 1933 */ 1934 if (zfsvfs->z_os) 1935 (void) zfs_umount(zfsvfs->z_sb); 1936 } 1937 return (err); 1938 } 1939 1940 /* 1941 * Release VOPs and unmount a suspended filesystem. 1942 */ 1943 int 1944 zfs_end_fs(zfsvfs_t *zfsvfs, dsl_dataset_t *ds) 1945 { 1946 ASSERT(ZFS_TEARDOWN_WRITE_HELD(zfsvfs)); 1947 ASSERT(RW_WRITE_HELD(&zfsvfs->z_teardown_inactive_lock)); 1948 1949 /* 1950 * We already own this, so just hold and rele it to update the 1951 * objset_t, as the one we had before may have been evicted. 1952 */ 1953 objset_t *os; 1954 VERIFY3P(ds->ds_owner, ==, zfsvfs); 1955 VERIFY(dsl_dataset_long_held(ds)); 1956 dsl_pool_t *dp = spa_get_dsl(dsl_dataset_get_spa(ds)); 1957 dsl_pool_config_enter(dp, FTAG); 1958 VERIFY0(dmu_objset_from_ds(ds, &os)); 1959 dsl_pool_config_exit(dp, FTAG); 1960 zfsvfs->z_os = os; 1961 1962 /* release the VOPs */ 1963 rw_exit(&zfsvfs->z_teardown_inactive_lock); 1964 ZFS_TEARDOWN_EXIT(zfsvfs, FTAG); 1965 1966 /* 1967 * Try to force unmount this file system. 1968 */ 1969 (void) zfs_umount(zfsvfs->z_sb); 1970 zfsvfs->z_unmounted = B_TRUE; 1971 return (0); 1972 } 1973 1974 /* 1975 * Automounted snapshots rely on periodic revalidation 1976 * to defer snapshots from being automatically unmounted. 1977 */ 1978 1979 inline void 1980 zfs_exit_fs(zfsvfs_t *zfsvfs) 1981 { 1982 if (!zfsvfs->z_issnap) 1983 return; 1984 1985 if (time_after(jiffies, zfsvfs->z_snap_defer_time + 1986 MAX(zfs_expire_snapshot * HZ / 2, HZ))) { 1987 zfsvfs->z_snap_defer_time = jiffies; 1988 zfsctl_snapshot_unmount_delay(zfsvfs->z_os->os_spa, 1989 dmu_objset_id(zfsvfs->z_os), 1990 zfs_expire_snapshot); 1991 } 1992 } 1993 1994 int 1995 zfs_set_version(zfsvfs_t *zfsvfs, uint64_t newvers) 1996 { 1997 int error; 1998 objset_t *os = zfsvfs->z_os; 1999 dmu_tx_t *tx; 2000 2001 if (newvers < ZPL_VERSION_INITIAL || newvers > ZPL_VERSION) 2002 return (SET_ERROR(EINVAL)); 2003 2004 if (newvers < zfsvfs->z_version) 2005 return (SET_ERROR(EINVAL)); 2006 2007 if (zfs_spa_version_map(newvers) > 2008 spa_version(dmu_objset_spa(zfsvfs->z_os))) 2009 return (SET_ERROR(ENOTSUP)); 2010 2011 tx = dmu_tx_create(os); 2012 dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, B_FALSE, ZPL_VERSION_STR); 2013 if (newvers >= ZPL_VERSION_SA && !zfsvfs->z_use_sa) { 2014 dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, B_TRUE, 2015 ZFS_SA_ATTRS); 2016 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL); 2017 } 2018 error = dmu_tx_assign(tx, TXG_WAIT); 2019 if (error) { 2020 dmu_tx_abort(tx); 2021 return (error); 2022 } 2023 2024 error = zap_update(os, MASTER_NODE_OBJ, ZPL_VERSION_STR, 2025 8, 1, &newvers, tx); 2026 2027 if (error) { 2028 dmu_tx_commit(tx); 2029 return (error); 2030 } 2031 2032 if (newvers >= ZPL_VERSION_SA && !zfsvfs->z_use_sa) { 2033 uint64_t sa_obj; 2034 2035 ASSERT3U(spa_version(dmu_objset_spa(zfsvfs->z_os)), >=, 2036 SPA_VERSION_SA); 2037 sa_obj = zap_create(os, DMU_OT_SA_MASTER_NODE, 2038 DMU_OT_NONE, 0, tx); 2039 2040 error = zap_add(os, MASTER_NODE_OBJ, 2041 ZFS_SA_ATTRS, 8, 1, &sa_obj, tx); 2042 ASSERT0(error); 2043 2044 VERIFY(0 == sa_set_sa_object(os, sa_obj)); 2045 sa_register_update_callback(os, zfs_sa_upgrade); 2046 } 2047 2048 spa_history_log_internal_ds(dmu_objset_ds(os), "upgrade", tx, 2049 "from %llu to %llu", zfsvfs->z_version, newvers); 2050 2051 dmu_tx_commit(tx); 2052 2053 zfsvfs->z_version = newvers; 2054 os->os_version = newvers; 2055 2056 zfs_set_fuid_feature(zfsvfs); 2057 2058 return (0); 2059 } 2060 2061 /* 2062 * Return true if the corresponding vfs's unmounted flag is set. 2063 * Otherwise return false. 2064 * If this function returns true we know VFS unmount has been initiated. 2065 */ 2066 boolean_t 2067 zfs_get_vfs_flag_unmounted(objset_t *os) 2068 { 2069 zfsvfs_t *zfvp; 2070 boolean_t unmounted = B_FALSE; 2071 2072 ASSERT(dmu_objset_type(os) == DMU_OST_ZFS); 2073 2074 mutex_enter(&os->os_user_ptr_lock); 2075 zfvp = dmu_objset_get_user(os); 2076 if (zfvp != NULL && zfvp->z_unmounted) 2077 unmounted = B_TRUE; 2078 mutex_exit(&os->os_user_ptr_lock); 2079 2080 return (unmounted); 2081 } 2082 2083 void 2084 zfsvfs_update_fromname(const char *oldname, const char *newname) 2085 { 2086 /* 2087 * We don't need to do anything here, the devname is always current by 2088 * virtue of zfsvfs->z_sb->s_op->show_devname. 2089 */ 2090 (void) oldname, (void) newname; 2091 } 2092 2093 void 2094 zfs_init(void) 2095 { 2096 zfsctl_init(); 2097 zfs_znode_init(); 2098 dmu_objset_register_type(DMU_OST_ZFS, zpl_get_file_info); 2099 register_filesystem(&zpl_fs_type); 2100 #ifdef HAVE_VFS_FILE_OPERATIONS_EXTEND 2101 register_fo_extend(&zpl_file_operations); 2102 #endif 2103 } 2104 2105 void 2106 zfs_fini(void) 2107 { 2108 /* 2109 * we don't use outstanding because zpl_posix_acl_free might add more. 2110 */ 2111 taskq_wait(system_delay_taskq); 2112 taskq_wait(system_taskq); 2113 #ifdef HAVE_VFS_FILE_OPERATIONS_EXTEND 2114 unregister_fo_extend(&zpl_file_operations); 2115 #endif 2116 unregister_filesystem(&zpl_fs_type); 2117 zfs_znode_fini(); 2118 zfsctl_fini(); 2119 } 2120 2121 #if defined(_KERNEL) 2122 EXPORT_SYMBOL(zfs_suspend_fs); 2123 EXPORT_SYMBOL(zfs_resume_fs); 2124 EXPORT_SYMBOL(zfs_set_version); 2125 EXPORT_SYMBOL(zfsvfs_create); 2126 EXPORT_SYMBOL(zfsvfs_free); 2127 EXPORT_SYMBOL(zfs_is_readonly); 2128 EXPORT_SYMBOL(zfs_domount); 2129 EXPORT_SYMBOL(zfs_preumount); 2130 EXPORT_SYMBOL(zfs_umount); 2131 EXPORT_SYMBOL(zfs_remount); 2132 EXPORT_SYMBOL(zfs_statvfs); 2133 EXPORT_SYMBOL(zfs_vget); 2134 EXPORT_SYMBOL(zfs_prune); 2135 #endif 2136