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 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/systm.h>
  31 #include <sys/sysmacros.h>
  32 #include <sys/kmem.h>
  33 #include <sys/pathname.h>
  34 #include <sys/vnode.h>
  35 #include <sys/vfs.h>
  36 #include <sys/vfs_opreg.h>
  37 #include <sys/mntent.h>
  38 #include <sys/mount.h>
  39 #include <sys/cmn_err.h>
  40 #include "fs/fs_subr.h"
  41 #include <sys/zfs_znode.h>
  42 #include <sys/zfs_dir.h>
  43 #include <sys/zil.h>
  44 #include <sys/fs/zfs.h>
  45 #include <sys/dmu.h>
  46 #include <sys/dsl_prop.h>
  47 #include <sys/dsl_dataset.h>
  48 #include <sys/dsl_deleg.h>
  49 #include <sys/spa.h>
  50 #include <sys/zap.h>
  51 #include <sys/sa.h>
  52 #include <sys/sa_impl.h>
  53 #include <sys/varargs.h>
  54 #include <sys/policy.h>
  55 #include <sys/atomic.h>
  56 #include <sys/mkdev.h>
  57 #include <sys/modctl.h>
  58 #include <sys/refstr.h>
  59 #include <sys/zfs_ioctl.h>
  60 #include <sys/zfs_ctldir.h>
  61 #include <sys/zfs_fuid.h>
  62 #include <sys/bootconf.h>
  63 #include <sys/sunddi.h>
  64 #include <sys/dnlc.h>
  65 #include <sys/dmu_objset.h>
  66 #include <sys/spa_boot.h>
  67 #include "zfs_comutil.h"
  68 
  69 int zfsfstype;
  70 vfsops_t *zfs_vfsops = NULL;
  71 static major_t zfs_major;
  72 static minor_t zfs_minor;
  73 static kmutex_t zfs_dev_mtx;
  74 
  75 extern int sys_shutdown;
  76 
  77 static int zfs_mount(vfs_t *vfsp, vnode_t *mvp, struct mounta *uap, cred_t *cr);
  78 static int zfs_umount(vfs_t *vfsp, int fflag, cred_t *cr);
  79 static int zfs_mountroot(vfs_t *vfsp, enum whymountroot);
  80 static int zfs_root(vfs_t *vfsp, vnode_t **vpp);
  81 static int zfs_statvfs(vfs_t *vfsp, struct statvfs64 *statp);
  82 static int zfs_vget(vfs_t *vfsp, vnode_t **vpp, fid_t *fidp);
  83 static void zfs_freevfs(vfs_t *vfsp);
  84 
  85 static const fs_operation_def_t zfs_vfsops_template[] = {
  86         VFSNAME_MOUNT,          { .vfs_mount = zfs_mount },
  87         VFSNAME_MOUNTROOT,      { .vfs_mountroot = zfs_mountroot },
  88         VFSNAME_UNMOUNT,        { .vfs_unmount = zfs_umount },
  89         VFSNAME_ROOT,           { .vfs_root = zfs_root },
  90         VFSNAME_STATVFS,        { .vfs_statvfs = zfs_statvfs },
  91         VFSNAME_SYNC,           { .vfs_sync = zfs_sync },
  92         VFSNAME_VGET,           { .vfs_vget = zfs_vget },
  93         VFSNAME_FREEVFS,        { .vfs_freevfs = zfs_freevfs },
  94         NULL,                   NULL
  95 };
  96 
  97 static const fs_operation_def_t zfs_vfsops_eio_template[] = {
  98         VFSNAME_FREEVFS,        { .vfs_freevfs =  zfs_freevfs },
  99         NULL,                   NULL
 100 };
 101 
 102 /*
 103  * We need to keep a count of active fs's.
 104  * This is necessary to prevent our module
 105  * from being unloaded after a umount -f
 106  */
 107 static uint32_t zfs_active_fs_count = 0;
 108 
 109 static char *noatime_cancel[] = { MNTOPT_ATIME, NULL };
 110 static char *atime_cancel[] = { MNTOPT_NOATIME, NULL };
 111 static char *noxattr_cancel[] = { MNTOPT_XATTR, NULL };
 112 static char *xattr_cancel[] = { MNTOPT_NOXATTR, NULL };
 113 
 114 /*
 115  * MO_DEFAULT is not used since the default value is determined
 116  * by the equivalent property.
 117  */
 118 static mntopt_t mntopts[] = {
 119         { MNTOPT_NOXATTR, noxattr_cancel, NULL, 0, NULL },
 120         { MNTOPT_XATTR, xattr_cancel, NULL, 0, NULL },
 121         { MNTOPT_NOATIME, noatime_cancel, NULL, 0, NULL },
 122         { MNTOPT_ATIME, atime_cancel, NULL, 0, NULL }
 123 };
 124 
 125 static mntopts_t zfs_mntopts = {
 126         sizeof (mntopts) / sizeof (mntopt_t),
 127         mntopts
 128 };
 129 
 130 /*ARGSUSED*/
 131 int
 132 zfs_sync(vfs_t *vfsp, short flag, cred_t *cr)
 133 {
 134         /*
 135          * Data integrity is job one.  We don't want a compromised kernel
 136          * writing to the storage pool, so we never sync during panic.
 137          */
 138         if (panicstr)
 139                 return (0);
 140 
 141         /*
 142          * SYNC_ATTR is used by fsflush() to force old filesystems like UFS
 143          * to sync metadata, which they would otherwise cache indefinitely.
 144          * Semantically, the only requirement is that the sync be initiated.
 145          * The DMU syncs out txgs frequently, so there's nothing to do.
 146          */
 147         if (flag & SYNC_ATTR)
 148                 return (0);
 149 
 150         if (vfsp != NULL) {
 151                 /*
 152                  * Sync a specific filesystem.
 153                  */
 154                 zfsvfs_t *zfsvfs = vfsp->vfs_data;
 155                 dsl_pool_t *dp;
 156 
 157                 ZFS_ENTER(zfsvfs);
 158                 dp = dmu_objset_pool(zfsvfs->z_os);
 159 
 160                 /*
 161                  * If the system is shutting down, then skip any
 162                  * filesystems which may exist on a suspended pool.
 163                  */
 164                 if (sys_shutdown && spa_suspended(dp->dp_spa)) {
 165                         ZFS_EXIT(zfsvfs);
 166                         return (0);
 167                 }
 168 
 169                 if (zfsvfs->z_log != NULL)
 170                         zil_commit(zfsvfs->z_log, 0);
 171 
 172                 ZFS_EXIT(zfsvfs);
 173         } else {
 174                 /*
 175                  * Sync all ZFS filesystems.  This is what happens when you
 176                  * run sync(1M).  Unlike other filesystems, ZFS honors the
 177                  * request by waiting for all pools to commit all dirty data.
 178                  */
 179                 spa_sync_allpools();
 180         }
 181 
 182         return (0);
 183 }
 184 
 185 static int
 186 zfs_create_unique_device(dev_t *dev)
 187 {
 188         major_t new_major;
 189 
 190         do {
 191                 ASSERT3U(zfs_minor, <=, MAXMIN32);
 192                 minor_t start = zfs_minor;
 193                 do {
 194                         mutex_enter(&zfs_dev_mtx);
 195                         if (zfs_minor >= MAXMIN32) {
 196                                 /*
 197                                  * If we're still using the real major
 198                                  * keep out of /dev/zfs and /dev/zvol minor
 199                                  * number space.  If we're using a getudev()'ed
 200                                  * major number, we can use all of its minors.
 201                                  */
 202                                 if (zfs_major == ddi_name_to_major(ZFS_DRIVER))
 203                                         zfs_minor = ZFS_MIN_MINOR;
 204                                 else
 205                                         zfs_minor = 0;
 206                         } else {
 207                                 zfs_minor++;
 208                         }
 209                         *dev = makedevice(zfs_major, zfs_minor);
 210                         mutex_exit(&zfs_dev_mtx);
 211                 } while (vfs_devismounted(*dev) && zfs_minor != start);
 212                 if (zfs_minor == start) {
 213                         /*
 214                          * We are using all ~262,000 minor numbers for the
 215                          * current major number.  Create a new major number.
 216                          */
 217                         if ((new_major = getudev()) == (major_t)-1) {
 218                                 cmn_err(CE_WARN,
 219                                     "zfs_mount: Can't get unique major "
 220                                     "device number.");
 221                                 return (-1);
 222                         }
 223                         mutex_enter(&zfs_dev_mtx);
 224                         zfs_major = new_major;
 225                         zfs_minor = 0;
 226 
 227                         mutex_exit(&zfs_dev_mtx);
 228                 } else {
 229                         break;
 230                 }
 231                 /* CONSTANTCONDITION */
 232         } while (1);
 233 
 234         return (0);
 235 }
 236 
 237 static void
 238 atime_changed_cb(void *arg, uint64_t newval)
 239 {
 240         zfsvfs_t *zfsvfs = arg;
 241 
 242         if (newval == TRUE) {
 243                 zfsvfs->z_atime = TRUE;
 244                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NOATIME);
 245                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_ATIME, NULL, 0);
 246         } else {
 247                 zfsvfs->z_atime = FALSE;
 248                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_ATIME);
 249                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NOATIME, NULL, 0);
 250         }
 251 }
 252 
 253 static void
 254 xattr_changed_cb(void *arg, uint64_t newval)
 255 {
 256         zfsvfs_t *zfsvfs = arg;
 257 
 258         if (newval == TRUE) {
 259                 /* XXX locking on vfs_flag? */
 260                 zfsvfs->z_vfs->vfs_flag |= VFS_XATTR;
 261                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NOXATTR);
 262                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_XATTR, NULL, 0);
 263         } else {
 264                 /* XXX locking on vfs_flag? */
 265                 zfsvfs->z_vfs->vfs_flag &= ~VFS_XATTR;
 266                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_XATTR);
 267                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NOXATTR, NULL, 0);
 268         }
 269 }
 270 
 271 static void
 272 blksz_changed_cb(void *arg, uint64_t newval)
 273 {
 274         zfsvfs_t *zfsvfs = arg;
 275 
 276         if (newval < SPA_MINBLOCKSIZE ||
 277             newval > SPA_MAXBLOCKSIZE || !ISP2(newval))
 278                 newval = SPA_MAXBLOCKSIZE;
 279 
 280         zfsvfs->z_max_blksz = newval;
 281         zfsvfs->z_vfs->vfs_bsize = newval;
 282 }
 283 
 284 static void
 285 readonly_changed_cb(void *arg, uint64_t newval)
 286 {
 287         zfsvfs_t *zfsvfs = arg;
 288 
 289         if (newval) {
 290                 /* XXX locking on vfs_flag? */
 291                 zfsvfs->z_vfs->vfs_flag |= VFS_RDONLY;
 292                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_RW);
 293                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_RO, NULL, 0);
 294         } else {
 295                 /* XXX locking on vfs_flag? */
 296                 zfsvfs->z_vfs->vfs_flag &= ~VFS_RDONLY;
 297                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_RO);
 298                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_RW, NULL, 0);
 299         }
 300 }
 301 
 302 static void
 303 devices_changed_cb(void *arg, uint64_t newval)
 304 {
 305         zfsvfs_t *zfsvfs = arg;
 306 
 307         if (newval == FALSE) {
 308                 zfsvfs->z_vfs->vfs_flag |= VFS_NODEVICES;
 309                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_DEVICES);
 310                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NODEVICES, NULL, 0);
 311         } else {
 312                 zfsvfs->z_vfs->vfs_flag &= ~VFS_NODEVICES;
 313                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NODEVICES);
 314                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_DEVICES, NULL, 0);
 315         }
 316 }
 317 
 318 static void
 319 setuid_changed_cb(void *arg, uint64_t newval)
 320 {
 321         zfsvfs_t *zfsvfs = arg;
 322 
 323         if (newval == FALSE) {
 324                 zfsvfs->z_vfs->vfs_flag |= VFS_NOSETUID;
 325                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_SETUID);
 326                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NOSETUID, NULL, 0);
 327         } else {
 328                 zfsvfs->z_vfs->vfs_flag &= ~VFS_NOSETUID;
 329                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NOSETUID);
 330                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_SETUID, NULL, 0);
 331         }
 332 }
 333 
 334 static void
 335 exec_changed_cb(void *arg, uint64_t newval)
 336 {
 337         zfsvfs_t *zfsvfs = arg;
 338 
 339         if (newval == FALSE) {
 340                 zfsvfs->z_vfs->vfs_flag |= VFS_NOEXEC;
 341                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_EXEC);
 342                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NOEXEC, NULL, 0);
 343         } else {
 344                 zfsvfs->z_vfs->vfs_flag &= ~VFS_NOEXEC;
 345                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NOEXEC);
 346                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_EXEC, NULL, 0);
 347         }
 348 }
 349 
 350 /*
 351  * The nbmand mount option can be changed at mount time.
 352  * We can't allow it to be toggled on live file systems or incorrect
 353  * behavior may be seen from cifs clients
 354  *
 355  * This property isn't registered via dsl_prop_register(), but this callback
 356  * will be called when a file system is first mounted
 357  */
 358 static void
 359 nbmand_changed_cb(void *arg, uint64_t newval)
 360 {
 361         zfsvfs_t *zfsvfs = arg;
 362         if (newval == FALSE) {
 363                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NBMAND);
 364                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NONBMAND, NULL, 0);
 365         } else {
 366                 vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NONBMAND);
 367                 vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NBMAND, NULL, 0);
 368         }
 369 }
 370 
 371 static void
 372 snapdir_changed_cb(void *arg, uint64_t newval)
 373 {
 374         zfsvfs_t *zfsvfs = arg;
 375 
 376         zfsvfs->z_show_ctldir = newval;
 377 }
 378 
 379 static void
 380 vscan_changed_cb(void *arg, uint64_t newval)
 381 {
 382         zfsvfs_t *zfsvfs = arg;
 383 
 384         zfsvfs->z_vscan = newval;
 385 }
 386 
 387 static void
 388 acl_mode_changed_cb(void *arg, uint64_t newval)
 389 {
 390         zfsvfs_t *zfsvfs = arg;
 391 
 392         zfsvfs->z_acl_mode = newval;
 393 }
 394 
 395 static void
 396 acl_inherit_changed_cb(void *arg, uint64_t newval)
 397 {
 398         zfsvfs_t *zfsvfs = arg;
 399 
 400         zfsvfs->z_acl_inherit = newval;
 401 }
 402 
 403 static int
 404 zfs_register_callbacks(vfs_t *vfsp)
 405 {
 406         struct dsl_dataset *ds = NULL;
 407         objset_t *os = NULL;
 408         zfsvfs_t *zfsvfs = NULL;
 409         uint64_t nbmand;
 410         boolean_t readonly = B_FALSE;
 411         boolean_t do_readonly = B_FALSE;
 412         boolean_t setuid = B_FALSE;
 413         boolean_t do_setuid = B_FALSE;
 414         boolean_t exec = B_FALSE;
 415         boolean_t do_exec = B_FALSE;
 416         boolean_t devices = B_FALSE;
 417         boolean_t do_devices = B_FALSE;
 418         boolean_t xattr = B_FALSE;
 419         boolean_t do_xattr = B_FALSE;
 420         boolean_t atime = B_FALSE;
 421         boolean_t do_atime = B_FALSE;
 422         int error = 0;
 423 
 424         ASSERT(vfsp);
 425         zfsvfs = vfsp->vfs_data;
 426         ASSERT(zfsvfs);
 427         os = zfsvfs->z_os;
 428 
 429         /*
 430          * The act of registering our callbacks will destroy any mount
 431          * options we may have.  In order to enable temporary overrides
 432          * of mount options, we stash away the current values and
 433          * restore them after we register the callbacks.
 434          */
 435         if (vfs_optionisset(vfsp, MNTOPT_RO, NULL) ||
 436             !spa_writeable(dmu_objset_spa(os))) {
 437                 readonly = B_TRUE;
 438                 do_readonly = B_TRUE;
 439         } else if (vfs_optionisset(vfsp, MNTOPT_RW, NULL)) {
 440                 readonly = B_FALSE;
 441                 do_readonly = B_TRUE;
 442         }
 443         if (vfs_optionisset(vfsp, MNTOPT_NOSUID, NULL)) {
 444                 devices = B_FALSE;
 445                 setuid = B_FALSE;
 446                 do_devices = B_TRUE;
 447                 do_setuid = B_TRUE;
 448         } else {
 449                 if (vfs_optionisset(vfsp, MNTOPT_NODEVICES, NULL)) {
 450                         devices = B_FALSE;
 451                         do_devices = B_TRUE;
 452                 } else if (vfs_optionisset(vfsp, MNTOPT_DEVICES, NULL)) {
 453                         devices = B_TRUE;
 454                         do_devices = B_TRUE;
 455                 }
 456 
 457                 if (vfs_optionisset(vfsp, MNTOPT_NOSETUID, NULL)) {
 458                         setuid = B_FALSE;
 459                         do_setuid = B_TRUE;
 460                 } else if (vfs_optionisset(vfsp, MNTOPT_SETUID, NULL)) {
 461                         setuid = B_TRUE;
 462                         do_setuid = B_TRUE;
 463                 }
 464         }
 465         if (vfs_optionisset(vfsp, MNTOPT_NOEXEC, NULL)) {
 466                 exec = B_FALSE;
 467                 do_exec = B_TRUE;
 468         } else if (vfs_optionisset(vfsp, MNTOPT_EXEC, NULL)) {
 469                 exec = B_TRUE;
 470                 do_exec = B_TRUE;
 471         }
 472         if (vfs_optionisset(vfsp, MNTOPT_NOXATTR, NULL)) {
 473                 xattr = B_FALSE;
 474                 do_xattr = B_TRUE;
 475         } else if (vfs_optionisset(vfsp, MNTOPT_XATTR, NULL)) {
 476                 xattr = B_TRUE;
 477                 do_xattr = B_TRUE;
 478         }
 479         if (vfs_optionisset(vfsp, MNTOPT_NOATIME, NULL)) {
 480                 atime = B_FALSE;
 481                 do_atime = B_TRUE;
 482         } else if (vfs_optionisset(vfsp, MNTOPT_ATIME, NULL)) {
 483                 atime = B_TRUE;
 484                 do_atime = B_TRUE;
 485         }
 486 
 487         /*
 488          * nbmand is a special property.  It can only be changed at
 489          * mount time.
 490          *
 491          * This is weird, but it is documented to only be changeable
 492          * at mount time.
 493          */
 494         if (vfs_optionisset(vfsp, MNTOPT_NONBMAND, NULL)) {
 495                 nbmand = B_FALSE;
 496         } else if (vfs_optionisset(vfsp, MNTOPT_NBMAND, NULL)) {
 497                 nbmand = B_TRUE;
 498         } else {
 499                 char osname[MAXNAMELEN];
 500 
 501                 dmu_objset_name(os, osname);
 502                 if (error = dsl_prop_get_integer(osname, "nbmand", &nbmand,
 503                     NULL)) {
 504                         return (error);
 505                 }
 506         }
 507 
 508         /*
 509          * Register property callbacks.
 510          *
 511          * It would probably be fine to just check for i/o error from
 512          * the first prop_register(), but I guess I like to go
 513          * overboard...
 514          */
 515         ds = dmu_objset_ds(os);
 516         dsl_pool_config_enter(dmu_objset_pool(os), FTAG);
 517         error = dsl_prop_register(ds,
 518             zfs_prop_to_name(ZFS_PROP_ATIME), atime_changed_cb, zfsvfs);
 519         error = error ? error : dsl_prop_register(ds,
 520             zfs_prop_to_name(ZFS_PROP_XATTR), xattr_changed_cb, zfsvfs);
 521         error = error ? error : dsl_prop_register(ds,
 522             zfs_prop_to_name(ZFS_PROP_RECORDSIZE), blksz_changed_cb, zfsvfs);
 523         error = error ? error : dsl_prop_register(ds,
 524             zfs_prop_to_name(ZFS_PROP_READONLY), readonly_changed_cb, zfsvfs);
 525         error = error ? error : dsl_prop_register(ds,
 526             zfs_prop_to_name(ZFS_PROP_DEVICES), devices_changed_cb, zfsvfs);
 527         error = error ? error : dsl_prop_register(ds,
 528             zfs_prop_to_name(ZFS_PROP_SETUID), setuid_changed_cb, zfsvfs);
 529         error = error ? error : dsl_prop_register(ds,
 530             zfs_prop_to_name(ZFS_PROP_EXEC), exec_changed_cb, zfsvfs);
 531         error = error ? error : dsl_prop_register(ds,
 532             zfs_prop_to_name(ZFS_PROP_SNAPDIR), snapdir_changed_cb, zfsvfs);
 533         error = error ? error : dsl_prop_register(ds,
 534             zfs_prop_to_name(ZFS_PROP_ACLMODE), acl_mode_changed_cb, zfsvfs);
 535         error = error ? error : dsl_prop_register(ds,
 536             zfs_prop_to_name(ZFS_PROP_ACLINHERIT), acl_inherit_changed_cb,
 537             zfsvfs);
 538         error = error ? error : dsl_prop_register(ds,
 539             zfs_prop_to_name(ZFS_PROP_VSCAN), vscan_changed_cb, zfsvfs);
 540         dsl_pool_config_exit(dmu_objset_pool(os), FTAG);
 541         if (error)
 542                 goto unregister;
 543 
 544         /*
 545          * Invoke our callbacks to restore temporary mount options.
 546          */
 547         if (do_readonly)
 548                 readonly_changed_cb(zfsvfs, readonly);
 549         if (do_setuid)
 550                 setuid_changed_cb(zfsvfs, setuid);
 551         if (do_exec)
 552                 exec_changed_cb(zfsvfs, exec);
 553         if (do_devices)
 554                 devices_changed_cb(zfsvfs, devices);
 555         if (do_xattr)
 556                 xattr_changed_cb(zfsvfs, xattr);
 557         if (do_atime)
 558                 atime_changed_cb(zfsvfs, atime);
 559 
 560         nbmand_changed_cb(zfsvfs, nbmand);
 561 
 562         return (0);
 563 
 564 unregister:
 565         /*
 566          * We may attempt to unregister some callbacks that are not
 567          * registered, but this is OK; it will simply return ENOMSG,
 568          * which we will ignore.
 569          */
 570         (void) dsl_prop_unregister(ds, zfs_prop_to_name(ZFS_PROP_ATIME),
 571             atime_changed_cb, zfsvfs);
 572         (void) dsl_prop_unregister(ds, zfs_prop_to_name(ZFS_PROP_XATTR),
 573             xattr_changed_cb, zfsvfs);
 574         (void) dsl_prop_unregister(ds, zfs_prop_to_name(ZFS_PROP_RECORDSIZE),
 575             blksz_changed_cb, zfsvfs);
 576         (void) dsl_prop_unregister(ds, zfs_prop_to_name(ZFS_PROP_READONLY),
 577             readonly_changed_cb, zfsvfs);
 578         (void) dsl_prop_unregister(ds, zfs_prop_to_name(ZFS_PROP_DEVICES),
 579             devices_changed_cb, zfsvfs);
 580         (void) dsl_prop_unregister(ds, zfs_prop_to_name(ZFS_PROP_SETUID),
 581             setuid_changed_cb, zfsvfs);
 582         (void) dsl_prop_unregister(ds, zfs_prop_to_name(ZFS_PROP_EXEC),
 583             exec_changed_cb, zfsvfs);
 584         (void) dsl_prop_unregister(ds, zfs_prop_to_name(ZFS_PROP_SNAPDIR),
 585             snapdir_changed_cb, zfsvfs);
 586         (void) dsl_prop_unregister(ds, zfs_prop_to_name(ZFS_PROP_ACLMODE),
 587             acl_mode_changed_cb, zfsvfs);
 588         (void) dsl_prop_unregister(ds, zfs_prop_to_name(ZFS_PROP_ACLINHERIT),
 589             acl_inherit_changed_cb, zfsvfs);
 590         (void) dsl_prop_unregister(ds, zfs_prop_to_name(ZFS_PROP_VSCAN),
 591             vscan_changed_cb, zfsvfs);
 592         return (error);
 593 }
 594 
 595 static int
 596 zfs_space_delta_cb(dmu_object_type_t bonustype, void *data,
 597     uint64_t *userp, uint64_t *groupp)
 598 {
 599         /*
 600          * Is it a valid type of object to track?
 601          */
 602         if (bonustype != DMU_OT_ZNODE && bonustype != DMU_OT_SA)
 603                 return (SET_ERROR(ENOENT));
 604 
 605         /*
 606          * If we have a NULL data pointer
 607          * then assume the id's aren't changing and
 608          * return EEXIST to the dmu to let it know to
 609          * use the same ids
 610          */
 611         if (data == NULL)
 612                 return (SET_ERROR(EEXIST));
 613 
 614         if (bonustype == DMU_OT_ZNODE) {
 615                 znode_phys_t *znp = data;
 616                 *userp = znp->zp_uid;
 617                 *groupp = znp->zp_gid;
 618         } else {
 619                 int hdrsize;
 620                 sa_hdr_phys_t *sap = data;
 621                 sa_hdr_phys_t sa = *sap;
 622                 boolean_t swap = B_FALSE;
 623 
 624                 ASSERT(bonustype == DMU_OT_SA);
 625 
 626                 if (sa.sa_magic == 0) {
 627                         /*
 628                          * This should only happen for newly created
 629                          * files that haven't had the znode data filled
 630                          * in yet.
 631                          */
 632                         *userp = 0;
 633                         *groupp = 0;
 634                         return (0);
 635                 }
 636                 if (sa.sa_magic == BSWAP_32(SA_MAGIC)) {
 637                         sa.sa_magic = SA_MAGIC;
 638                         sa.sa_layout_info = BSWAP_16(sa.sa_layout_info);
 639                         swap = B_TRUE;
 640                 } else {
 641                         VERIFY3U(sa.sa_magic, ==, SA_MAGIC);
 642                 }
 643 
 644                 hdrsize = sa_hdrsize(&sa);
 645                 VERIFY3U(hdrsize, >=, sizeof (sa_hdr_phys_t));
 646                 *userp = *((uint64_t *)((uintptr_t)data + hdrsize +
 647                     SA_UID_OFFSET));
 648                 *groupp = *((uint64_t *)((uintptr_t)data + hdrsize +
 649                     SA_GID_OFFSET));
 650                 if (swap) {
 651                         *userp = BSWAP_64(*userp);
 652                         *groupp = BSWAP_64(*groupp);
 653                 }
 654         }
 655         return (0);
 656 }
 657 
 658 static void
 659 fuidstr_to_sid(zfsvfs_t *zfsvfs, const char *fuidstr,
 660     char *domainbuf, int buflen, uid_t *ridp)
 661 {
 662         uint64_t fuid;
 663         const char *domain;
 664 
 665         fuid = strtonum(fuidstr, NULL);
 666 
 667         domain = zfs_fuid_find_by_idx(zfsvfs, FUID_INDEX(fuid));
 668         if (domain)
 669                 (void) strlcpy(domainbuf, domain, buflen);
 670         else
 671                 domainbuf[0] = '\0';
 672         *ridp = FUID_RID(fuid);
 673 }
 674 
 675 static uint64_t
 676 zfs_userquota_prop_to_obj(zfsvfs_t *zfsvfs, zfs_userquota_prop_t type)
 677 {
 678         switch (type) {
 679         case ZFS_PROP_USERUSED:
 680                 return (DMU_USERUSED_OBJECT);
 681         case ZFS_PROP_GROUPUSED:
 682                 return (DMU_GROUPUSED_OBJECT);
 683         case ZFS_PROP_USERQUOTA:
 684                 return (zfsvfs->z_userquota_obj);
 685         case ZFS_PROP_GROUPQUOTA:
 686                 return (zfsvfs->z_groupquota_obj);
 687         }
 688         return (0);
 689 }
 690 
 691 int
 692 zfs_userspace_many(zfsvfs_t *zfsvfs, zfs_userquota_prop_t type,
 693     uint64_t *cookiep, void *vbuf, uint64_t *bufsizep)
 694 {
 695         int error;
 696         zap_cursor_t zc;
 697         zap_attribute_t za;
 698         zfs_useracct_t *buf = vbuf;
 699         uint64_t obj;
 700 
 701         if (!dmu_objset_userspace_present(zfsvfs->z_os))
 702                 return (SET_ERROR(ENOTSUP));
 703 
 704         obj = zfs_userquota_prop_to_obj(zfsvfs, type);
 705         if (obj == 0) {
 706                 *bufsizep = 0;
 707                 return (0);
 708         }
 709 
 710         for (zap_cursor_init_serialized(&zc, zfsvfs->z_os, obj, *cookiep);
 711             (error = zap_cursor_retrieve(&zc, &za)) == 0;
 712             zap_cursor_advance(&zc)) {
 713                 if ((uintptr_t)buf - (uintptr_t)vbuf + sizeof (zfs_useracct_t) >
 714                     *bufsizep)
 715                         break;
 716 
 717                 fuidstr_to_sid(zfsvfs, za.za_name,
 718                     buf->zu_domain, sizeof (buf->zu_domain), &buf->zu_rid);
 719 
 720                 buf->zu_space = za.za_first_integer;
 721                 buf++;
 722         }
 723         if (error == ENOENT)
 724                 error = 0;
 725 
 726         ASSERT3U((uintptr_t)buf - (uintptr_t)vbuf, <=, *bufsizep);
 727         *bufsizep = (uintptr_t)buf - (uintptr_t)vbuf;
 728         *cookiep = zap_cursor_serialize(&zc);
 729         zap_cursor_fini(&zc);
 730         return (error);
 731 }
 732 
 733 /*
 734  * buf must be big enough (eg, 32 bytes)
 735  */
 736 static int
 737 id_to_fuidstr(zfsvfs_t *zfsvfs, const char *domain, uid_t rid,
 738     char *buf, boolean_t addok)
 739 {
 740         uint64_t fuid;
 741         int domainid = 0;
 742 
 743         if (domain && domain[0]) {
 744                 domainid = zfs_fuid_find_by_domain(zfsvfs, domain, NULL, addok);
 745                 if (domainid == -1)
 746                         return (SET_ERROR(ENOENT));
 747         }
 748         fuid = FUID_ENCODE(domainid, rid);
 749         (void) sprintf(buf, "%llx", (longlong_t)fuid);
 750         return (0);
 751 }
 752 
 753 int
 754 zfs_userspace_one(zfsvfs_t *zfsvfs, zfs_userquota_prop_t type,
 755     const char *domain, uint64_t rid, uint64_t *valp)
 756 {
 757         char buf[32];
 758         int err;
 759         uint64_t obj;
 760 
 761         *valp = 0;
 762 
 763         if (!dmu_objset_userspace_present(zfsvfs->z_os))
 764                 return (SET_ERROR(ENOTSUP));
 765 
 766         obj = zfs_userquota_prop_to_obj(zfsvfs, type);
 767         if (obj == 0)
 768                 return (0);
 769 
 770         err = id_to_fuidstr(zfsvfs, domain, rid, buf, B_FALSE);
 771         if (err)
 772                 return (err);
 773 
 774         err = zap_lookup(zfsvfs->z_os, obj, buf, 8, 1, valp);
 775         if (err == ENOENT)
 776                 err = 0;
 777         return (err);
 778 }
 779 
 780 int
 781 zfs_set_userquota(zfsvfs_t *zfsvfs, zfs_userquota_prop_t type,
 782     const char *domain, uint64_t rid, uint64_t quota)
 783 {
 784         char buf[32];
 785         int err;
 786         dmu_tx_t *tx;
 787         uint64_t *objp;
 788         boolean_t fuid_dirtied;
 789 
 790         if (type != ZFS_PROP_USERQUOTA && type != ZFS_PROP_GROUPQUOTA)
 791                 return (SET_ERROR(EINVAL));
 792 
 793         if (zfsvfs->z_version < ZPL_VERSION_USERSPACE)
 794                 return (SET_ERROR(ENOTSUP));
 795 
 796         objp = (type == ZFS_PROP_USERQUOTA) ? &zfsvfs->z_userquota_obj :
 797             &zfsvfs->z_groupquota_obj;
 798 
 799         err = id_to_fuidstr(zfsvfs, domain, rid, buf, B_TRUE);
 800         if (err)
 801                 return (err);
 802         fuid_dirtied = zfsvfs->z_fuid_dirty;
 803 
 804         tx = dmu_tx_create(zfsvfs->z_os);
 805         dmu_tx_hold_zap(tx, *objp ? *objp : DMU_NEW_OBJECT, B_TRUE, NULL);
 806         if (*objp == 0) {
 807                 dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, B_TRUE,
 808                     zfs_userquota_prop_prefixes[type]);
 809         }
 810         if (fuid_dirtied)
 811                 zfs_fuid_txhold(zfsvfs, tx);
 812         err = dmu_tx_assign(tx, TXG_WAIT);
 813         if (err) {
 814                 dmu_tx_abort(tx);
 815                 return (err);
 816         }
 817 
 818         mutex_enter(&zfsvfs->z_lock);
 819         if (*objp == 0) {
 820                 *objp = zap_create(zfsvfs->z_os, DMU_OT_USERGROUP_QUOTA,
 821                     DMU_OT_NONE, 0, tx);
 822                 VERIFY(0 == zap_add(zfsvfs->z_os, MASTER_NODE_OBJ,
 823                     zfs_userquota_prop_prefixes[type], 8, 1, objp, tx));
 824         }
 825         mutex_exit(&zfsvfs->z_lock);
 826 
 827         if (quota == 0) {
 828                 err = zap_remove(zfsvfs->z_os, *objp, buf, tx);
 829                 if (err == ENOENT)
 830                         err = 0;
 831         } else {
 832                 err = zap_update(zfsvfs->z_os, *objp, buf, 8, 1, &quota, tx);
 833         }
 834         ASSERT(err == 0);
 835         if (fuid_dirtied)
 836                 zfs_fuid_sync(zfsvfs, tx);
 837         dmu_tx_commit(tx);
 838         return (err);
 839 }
 840 
 841 boolean_t
 842 zfs_fuid_overquota(zfsvfs_t *zfsvfs, boolean_t isgroup, uint64_t fuid)
 843 {
 844         char buf[32];
 845         uint64_t used, quota, usedobj, quotaobj;
 846         int err;
 847 
 848         usedobj = isgroup ? DMU_GROUPUSED_OBJECT : DMU_USERUSED_OBJECT;
 849         quotaobj = isgroup ? zfsvfs->z_groupquota_obj : zfsvfs->z_userquota_obj;
 850 
 851         if (quotaobj == 0 || zfsvfs->z_replay)
 852                 return (B_FALSE);
 853 
 854         (void) sprintf(buf, "%llx", (longlong_t)fuid);
 855         err = zap_lookup(zfsvfs->z_os, quotaobj, buf, 8, 1, &quota);
 856         if (err != 0)
 857                 return (B_FALSE);
 858 
 859         err = zap_lookup(zfsvfs->z_os, usedobj, buf, 8, 1, &used);
 860         if (err != 0)
 861                 return (B_FALSE);
 862         return (used >= quota);
 863 }
 864 
 865 boolean_t
 866 zfs_owner_overquota(zfsvfs_t *zfsvfs, znode_t *zp, boolean_t isgroup)
 867 {
 868         uint64_t fuid;
 869         uint64_t quotaobj;
 870 
 871         quotaobj = isgroup ? zfsvfs->z_groupquota_obj : zfsvfs->z_userquota_obj;
 872 
 873         fuid = isgroup ? zp->z_gid : zp->z_uid;
 874 
 875         if (quotaobj == 0 || zfsvfs->z_replay)
 876                 return (B_FALSE);
 877 
 878         return (zfs_fuid_overquota(zfsvfs, isgroup, fuid));
 879 }
 880 
 881 int
 882 zfsvfs_create(const char *osname, zfsvfs_t **zfvp)
 883 {
 884         objset_t *os;
 885         zfsvfs_t *zfsvfs;
 886         uint64_t zval;
 887         int i, error;
 888         uint64_t sa_obj;
 889 
 890         zfsvfs = kmem_zalloc(sizeof (zfsvfs_t), KM_SLEEP);
 891 
 892         /*
 893          * We claim to always be readonly so we can open snapshots;
 894          * other ZPL code will prevent us from writing to snapshots.
 895          */
 896         error = dmu_objset_own(osname, DMU_OST_ZFS, B_TRUE, zfsvfs, &os);
 897         if (error) {
 898                 kmem_free(zfsvfs, sizeof (zfsvfs_t));
 899                 return (error);
 900         }
 901 
 902         /*
 903          * Initialize the zfs-specific filesystem structure.
 904          * Should probably make this a kmem cache, shuffle fields,
 905          * and just bzero up to z_hold_mtx[].
 906          */
 907         zfsvfs->z_vfs = NULL;
 908         zfsvfs->z_parent = zfsvfs;
 909         zfsvfs->z_max_blksz = SPA_MAXBLOCKSIZE;
 910         zfsvfs->z_show_ctldir = ZFS_SNAPDIR_VISIBLE;
 911         zfsvfs->z_os = os;
 912 
 913         error = zfs_get_zplprop(os, ZFS_PROP_VERSION, &zfsvfs->z_version);
 914         if (error) {
 915                 goto out;
 916         } else if (zfsvfs->z_version >
 917             zfs_zpl_version_map(spa_version(dmu_objset_spa(os)))) {
 918                 (void) printf("Can't mount a version %lld file system "
 919                     "on a version %lld pool\n. Pool must be upgraded to mount "
 920                     "this file system.", (u_longlong_t)zfsvfs->z_version,
 921                     (u_longlong_t)spa_version(dmu_objset_spa(os)));
 922                 error = SET_ERROR(ENOTSUP);
 923                 goto out;
 924         }
 925         if ((error = zfs_get_zplprop(os, ZFS_PROP_NORMALIZE, &zval)) != 0)
 926                 goto out;
 927         zfsvfs->z_norm = (int)zval;
 928 
 929         if ((error = zfs_get_zplprop(os, ZFS_PROP_UTF8ONLY, &zval)) != 0)
 930                 goto out;
 931         zfsvfs->z_utf8 = (zval != 0);
 932 
 933         if ((error = zfs_get_zplprop(os, ZFS_PROP_CASE, &zval)) != 0)
 934                 goto out;
 935         zfsvfs->z_case = (uint_t)zval;
 936 
 937         /*
 938          * Fold case on file systems that are always or sometimes case
 939          * insensitive.
 940          */
 941         if (zfsvfs->z_case == ZFS_CASE_INSENSITIVE ||
 942             zfsvfs->z_case == ZFS_CASE_MIXED)
 943                 zfsvfs->z_norm |= U8_TEXTPREP_TOUPPER;
 944 
 945         zfsvfs->z_use_fuids = USE_FUIDS(zfsvfs->z_version, zfsvfs->z_os);
 946         zfsvfs->z_use_sa = USE_SA(zfsvfs->z_version, zfsvfs->z_os);
 947 
 948         if (zfsvfs->z_use_sa) {
 949                 /* should either have both of these objects or none */
 950                 error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_SA_ATTRS, 8, 1,
 951                     &sa_obj);
 952                 if (error)
 953                         return (error);
 954         } else {
 955                 /*
 956                  * Pre SA versions file systems should never touch
 957                  * either the attribute registration or layout objects.
 958                  */
 959                 sa_obj = 0;
 960         }
 961 
 962         error = sa_setup(os, sa_obj, zfs_attr_table, ZPL_END,
 963             &zfsvfs->z_attr_table);
 964         if (error)
 965                 goto out;
 966 
 967         if (zfsvfs->z_version >= ZPL_VERSION_SA)
 968                 sa_register_update_callback(os, zfs_sa_upgrade);
 969 
 970         error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_ROOT_OBJ, 8, 1,
 971             &zfsvfs->z_root);
 972         if (error)
 973                 goto out;
 974         ASSERT(zfsvfs->z_root != 0);
 975 
 976         error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_UNLINKED_SET, 8, 1,
 977             &zfsvfs->z_unlinkedobj);
 978         if (error)
 979                 goto out;
 980 
 981         error = zap_lookup(os, MASTER_NODE_OBJ,
 982             zfs_userquota_prop_prefixes[ZFS_PROP_USERQUOTA],
 983             8, 1, &zfsvfs->z_userquota_obj);
 984         if (error && error != ENOENT)
 985                 goto out;
 986 
 987         error = zap_lookup(os, MASTER_NODE_OBJ,
 988             zfs_userquota_prop_prefixes[ZFS_PROP_GROUPQUOTA],
 989             8, 1, &zfsvfs->z_groupquota_obj);
 990         if (error && error != ENOENT)
 991                 goto out;
 992 
 993         error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_FUID_TABLES, 8, 1,
 994             &zfsvfs->z_fuid_obj);
 995         if (error && error != ENOENT)
 996                 goto out;
 997 
 998         error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_SHARES_DIR, 8, 1,
 999             &zfsvfs->z_shares_dir);
1000         if (error && error != ENOENT)
1001                 goto out;
1002 
1003         mutex_init(&zfsvfs->z_znodes_lock, NULL, MUTEX_DEFAULT, NULL);
1004         mutex_init(&zfsvfs->z_lock, NULL, MUTEX_DEFAULT, NULL);
1005         list_create(&zfsvfs->z_all_znodes, sizeof (znode_t),
1006             offsetof(znode_t, z_link_node));
1007         rrw_init(&zfsvfs->z_teardown_lock, B_FALSE);
1008         rw_init(&zfsvfs->z_teardown_inactive_lock, NULL, RW_DEFAULT, NULL);
1009         rw_init(&zfsvfs->z_fuid_lock, NULL, RW_DEFAULT, NULL);
1010         for (i = 0; i != ZFS_OBJ_MTX_SZ; i++)
1011                 mutex_init(&zfsvfs->z_hold_mtx[i], NULL, MUTEX_DEFAULT, NULL);
1012 
1013         *zfvp = zfsvfs;
1014         return (0);
1015 
1016 out:
1017         dmu_objset_disown(os, zfsvfs);
1018         *zfvp = NULL;
1019         kmem_free(zfsvfs, sizeof (zfsvfs_t));
1020         return (error);
1021 }
1022 
1023 static int
1024 zfsvfs_setup(zfsvfs_t *zfsvfs, boolean_t mounting)
1025 {
1026         int error;
1027 
1028         error = zfs_register_callbacks(zfsvfs->z_vfs);
1029         if (error)
1030                 return (error);
1031 
1032         /*
1033          * Set the objset user_ptr to track its zfsvfs.
1034          */
1035         mutex_enter(&zfsvfs->z_os->os_user_ptr_lock);
1036         dmu_objset_set_user(zfsvfs->z_os, zfsvfs);
1037         mutex_exit(&zfsvfs->z_os->os_user_ptr_lock);
1038 
1039         zfsvfs->z_log = zil_open(zfsvfs->z_os, zfs_get_data);
1040 
1041         /*
1042          * If we are not mounting (ie: online recv), then we don't
1043          * have to worry about replaying the log as we blocked all
1044          * operations out since we closed the ZIL.
1045          */
1046         if (mounting) {
1047                 boolean_t readonly;
1048 
1049                 /*
1050                  * During replay we remove the read only flag to
1051                  * allow replays to succeed.
1052                  */
1053                 readonly = zfsvfs->z_vfs->vfs_flag & VFS_RDONLY;
1054                 if (readonly != 0)
1055                         zfsvfs->z_vfs->vfs_flag &= ~VFS_RDONLY;
1056                 else
1057                         zfs_unlinked_drain(zfsvfs);
1058 
1059                 /*
1060                  * Parse and replay the intent log.
1061                  *
1062                  * Because of ziltest, this must be done after
1063                  * zfs_unlinked_drain().  (Further note: ziltest
1064                  * doesn't use readonly mounts, where
1065                  * zfs_unlinked_drain() isn't called.)  This is because
1066                  * ziltest causes spa_sync() to think it's committed,
1067                  * but actually it is not, so the intent log contains
1068                  * many txg's worth of changes.
1069                  *
1070                  * In particular, if object N is in the unlinked set in
1071                  * the last txg to actually sync, then it could be
1072                  * actually freed in a later txg and then reallocated
1073                  * in a yet later txg.  This would write a "create
1074                  * object N" record to the intent log.  Normally, this
1075                  * would be fine because the spa_sync() would have
1076                  * written out the fact that object N is free, before
1077                  * we could write the "create object N" intent log
1078                  * record.
1079                  *
1080                  * But when we are in ziltest mode, we advance the "open
1081                  * txg" without actually spa_sync()-ing the changes to
1082                  * disk.  So we would see that object N is still
1083                  * allocated and in the unlinked set, and there is an
1084                  * intent log record saying to allocate it.
1085                  */
1086                 if (spa_writeable(dmu_objset_spa(zfsvfs->z_os))) {
1087                         if (zil_replay_disable) {
1088                                 zil_destroy(zfsvfs->z_log, B_FALSE);
1089                         } else {
1090                                 zfsvfs->z_replay = B_TRUE;
1091                                 zil_replay(zfsvfs->z_os, zfsvfs,
1092                                     zfs_replay_vector);
1093                                 zfsvfs->z_replay = B_FALSE;
1094                         }
1095                 }
1096                 zfsvfs->z_vfs->vfs_flag |= readonly; /* restore readonly bit */
1097         }
1098 
1099         return (0);
1100 }
1101 
1102 void
1103 zfsvfs_free(zfsvfs_t *zfsvfs)
1104 {
1105         int i;
1106         extern krwlock_t zfsvfs_lock; /* in zfs_znode.c */
1107 
1108         /*
1109          * This is a barrier to prevent the filesystem from going away in
1110          * zfs_znode_move() until we can safely ensure that the filesystem is
1111          * not unmounted. We consider the filesystem valid before the barrier
1112          * and invalid after the barrier.
1113          */
1114         rw_enter(&zfsvfs_lock, RW_READER);
1115         rw_exit(&zfsvfs_lock);
1116 
1117         zfs_fuid_destroy(zfsvfs);
1118 
1119         mutex_destroy(&zfsvfs->z_znodes_lock);
1120         mutex_destroy(&zfsvfs->z_lock);
1121         list_destroy(&zfsvfs->z_all_znodes);
1122         rrw_destroy(&zfsvfs->z_teardown_lock);
1123         rw_destroy(&zfsvfs->z_teardown_inactive_lock);
1124         rw_destroy(&zfsvfs->z_fuid_lock);
1125         for (i = 0; i != ZFS_OBJ_MTX_SZ; i++)
1126                 mutex_destroy(&zfsvfs->z_hold_mtx[i]);
1127         kmem_free(zfsvfs, sizeof (zfsvfs_t));
1128 }
1129 
1130 static void
1131 zfs_set_fuid_feature(zfsvfs_t *zfsvfs)
1132 {
1133         zfsvfs->z_use_fuids = USE_FUIDS(zfsvfs->z_version, zfsvfs->z_os);
1134         if (zfsvfs->z_vfs) {
1135                 if (zfsvfs->z_use_fuids) {
1136                         vfs_set_feature(zfsvfs->z_vfs, VFSFT_XVATTR);
1137                         vfs_set_feature(zfsvfs->z_vfs, VFSFT_SYSATTR_VIEWS);
1138                         vfs_set_feature(zfsvfs->z_vfs, VFSFT_ACEMASKONACCESS);
1139                         vfs_set_feature(zfsvfs->z_vfs, VFSFT_ACLONCREATE);
1140                         vfs_set_feature(zfsvfs->z_vfs, VFSFT_ACCESS_FILTER);
1141                         vfs_set_feature(zfsvfs->z_vfs, VFSFT_REPARSE);
1142                 } else {
1143                         vfs_clear_feature(zfsvfs->z_vfs, VFSFT_XVATTR);
1144                         vfs_clear_feature(zfsvfs->z_vfs, VFSFT_SYSATTR_VIEWS);
1145                         vfs_clear_feature(zfsvfs->z_vfs, VFSFT_ACEMASKONACCESS);
1146                         vfs_clear_feature(zfsvfs->z_vfs, VFSFT_ACLONCREATE);
1147                         vfs_clear_feature(zfsvfs->z_vfs, VFSFT_ACCESS_FILTER);
1148                         vfs_clear_feature(zfsvfs->z_vfs, VFSFT_REPARSE);
1149                 }
1150         }
1151         zfsvfs->z_use_sa = USE_SA(zfsvfs->z_version, zfsvfs->z_os);
1152 }
1153 
1154 static int
1155 zfs_domount(vfs_t *vfsp, char *osname)
1156 {
1157         dev_t mount_dev;
1158         uint64_t recordsize, fsid_guid;
1159         int error = 0;
1160         zfsvfs_t *zfsvfs;
1161 
1162         ASSERT(vfsp);
1163         ASSERT(osname);
1164 
1165         error = zfsvfs_create(osname, &zfsvfs);
1166         if (error)
1167                 return (error);
1168         zfsvfs->z_vfs = vfsp;
1169 
1170         /* Initialize the generic filesystem structure. */
1171         vfsp->vfs_bcount = 0;
1172         vfsp->vfs_data = NULL;
1173 
1174         if (zfs_create_unique_device(&mount_dev) == -1) {
1175                 error = SET_ERROR(ENODEV);
1176                 goto out;
1177         }
1178         ASSERT(vfs_devismounted(mount_dev) == 0);
1179 
1180         if (error = dsl_prop_get_integer(osname, "recordsize", &recordsize,
1181             NULL))
1182                 goto out;
1183 
1184         vfsp->vfs_dev = mount_dev;
1185         vfsp->vfs_fstype = zfsfstype;
1186         vfsp->vfs_bsize = recordsize;
1187         vfsp->vfs_flag |= VFS_NOTRUNC;
1188         vfsp->vfs_data = zfsvfs;
1189 
1190         /*
1191          * The fsid is 64 bits, composed of an 8-bit fs type, which
1192          * separates our fsid from any other filesystem types, and a
1193          * 56-bit objset unique ID.  The objset unique ID is unique to
1194          * all objsets open on this system, provided by unique_create().
1195          * The 8-bit fs type must be put in the low bits of fsid[1]
1196          * because that's where other Solaris filesystems put it.
1197          */
1198         fsid_guid = dmu_objset_fsid_guid(zfsvfs->z_os);
1199         ASSERT((fsid_guid & ~((1ULL<<56)-1)) == 0);
1200         vfsp->vfs_fsid.val[0] = fsid_guid;
1201         vfsp->vfs_fsid.val[1] = ((fsid_guid>>32) << 8) |
1202             zfsfstype & 0xFF;
1203 
1204         /*
1205          * Set features for file system.
1206          */
1207         zfs_set_fuid_feature(zfsvfs);
1208         if (zfsvfs->z_case == ZFS_CASE_INSENSITIVE) {
1209                 vfs_set_feature(vfsp, VFSFT_DIRENTFLAGS);
1210                 vfs_set_feature(vfsp, VFSFT_CASEINSENSITIVE);
1211                 vfs_set_feature(vfsp, VFSFT_NOCASESENSITIVE);
1212         } else if (zfsvfs->z_case == ZFS_CASE_MIXED) {
1213                 vfs_set_feature(vfsp, VFSFT_DIRENTFLAGS);
1214                 vfs_set_feature(vfsp, VFSFT_CASEINSENSITIVE);
1215         }
1216         vfs_set_feature(vfsp, VFSFT_ZEROCOPY_SUPPORTED);
1217 
1218         if (dmu_objset_is_snapshot(zfsvfs->z_os)) {
1219                 uint64_t pval;
1220 
1221                 atime_changed_cb(zfsvfs, B_FALSE);
1222                 readonly_changed_cb(zfsvfs, B_TRUE);
1223                 if (error = dsl_prop_get_integer(osname, "xattr", &pval, NULL))
1224                         goto out;
1225                 xattr_changed_cb(zfsvfs, pval);
1226                 zfsvfs->z_issnap = B_TRUE;
1227                 zfsvfs->z_os->os_sync = ZFS_SYNC_DISABLED;
1228 
1229                 mutex_enter(&zfsvfs->z_os->os_user_ptr_lock);
1230                 dmu_objset_set_user(zfsvfs->z_os, zfsvfs);
1231                 mutex_exit(&zfsvfs->z_os->os_user_ptr_lock);
1232         } else {
1233                 error = zfsvfs_setup(zfsvfs, B_TRUE);
1234         }
1235 
1236         if (!zfsvfs->z_issnap)
1237                 zfsctl_create(zfsvfs);
1238 out:
1239         if (error) {
1240                 dmu_objset_disown(zfsvfs->z_os, zfsvfs);
1241                 zfsvfs_free(zfsvfs);
1242         } else {
1243                 atomic_add_32(&zfs_active_fs_count, 1);
1244         }
1245 
1246         return (error);
1247 }
1248 
1249 void
1250 zfs_unregister_callbacks(zfsvfs_t *zfsvfs)
1251 {
1252         objset_t *os = zfsvfs->z_os;
1253         struct dsl_dataset *ds;
1254 
1255         /*
1256          * Unregister properties.
1257          */
1258         if (!dmu_objset_is_snapshot(os)) {
1259                 ds = dmu_objset_ds(os);
1260                 VERIFY(dsl_prop_unregister(ds, "atime", atime_changed_cb,
1261                     zfsvfs) == 0);
1262 
1263                 VERIFY(dsl_prop_unregister(ds, "xattr", xattr_changed_cb,
1264                     zfsvfs) == 0);
1265 
1266                 VERIFY(dsl_prop_unregister(ds, "recordsize", blksz_changed_cb,
1267                     zfsvfs) == 0);
1268 
1269                 VERIFY(dsl_prop_unregister(ds, "readonly", readonly_changed_cb,
1270                     zfsvfs) == 0);
1271 
1272                 VERIFY(dsl_prop_unregister(ds, "devices", devices_changed_cb,
1273                     zfsvfs) == 0);
1274 
1275                 VERIFY(dsl_prop_unregister(ds, "setuid", setuid_changed_cb,
1276                     zfsvfs) == 0);
1277 
1278                 VERIFY(dsl_prop_unregister(ds, "exec", exec_changed_cb,
1279                     zfsvfs) == 0);
1280 
1281                 VERIFY(dsl_prop_unregister(ds, "snapdir", snapdir_changed_cb,
1282                     zfsvfs) == 0);
1283 
1284                 VERIFY(dsl_prop_unregister(ds, "aclmode", acl_mode_changed_cb,
1285                     zfsvfs) == 0);
1286 
1287                 VERIFY(dsl_prop_unregister(ds, "aclinherit",
1288                     acl_inherit_changed_cb, zfsvfs) == 0);
1289 
1290                 VERIFY(dsl_prop_unregister(ds, "vscan",
1291                     vscan_changed_cb, zfsvfs) == 0);
1292         }
1293 }
1294 
1295 /*
1296  * Convert a decimal digit string to a uint64_t integer.
1297  */
1298 static int
1299 str_to_uint64(char *str, uint64_t *objnum)
1300 {
1301         uint64_t num = 0;
1302 
1303         while (*str) {
1304                 if (*str < '0' || *str > '9')
1305                         return (SET_ERROR(EINVAL));
1306 
1307                 num = num*10 + *str++ - '0';
1308         }
1309 
1310         *objnum = num;
1311         return (0);
1312 }
1313 
1314 /*
1315  * The boot path passed from the boot loader is in the form of
1316  * "rootpool-name/root-filesystem-object-number'. Convert this
1317  * string to a dataset name: "rootpool-name/root-filesystem-name".
1318  */
1319 static int
1320 zfs_parse_bootfs(char *bpath, char *outpath)
1321 {
1322         char *slashp;
1323         uint64_t objnum;
1324         int error;
1325 
1326         if (*bpath == 0 || *bpath == '/')
1327                 return (SET_ERROR(EINVAL));
1328 
1329         (void) strcpy(outpath, bpath);
1330 
1331         slashp = strchr(bpath, '/');
1332 
1333         /* if no '/', just return the pool name */
1334         if (slashp == NULL) {
1335                 return (0);
1336         }
1337 
1338         /* if not a number, just return the root dataset name */
1339         if (str_to_uint64(slashp+1, &objnum)) {
1340                 return (0);
1341         }
1342 
1343         *slashp = '\0';
1344         error = dsl_dsobj_to_dsname(bpath, objnum, outpath);
1345         *slashp = '/';
1346 
1347         return (error);
1348 }
1349 
1350 /*
1351  * Check that the hex label string is appropriate for the dataset being
1352  * mounted into the global_zone proper.
1353  *
1354  * Return an error if the hex label string is not default or
1355  * admin_low/admin_high.  For admin_low labels, the corresponding
1356  * dataset must be readonly.
1357  */
1358 int
1359 zfs_check_global_label(const char *dsname, const char *hexsl)
1360 {
1361         if (strcasecmp(hexsl, ZFS_MLSLABEL_DEFAULT) == 0)
1362                 return (0);
1363         if (strcasecmp(hexsl, ADMIN_HIGH) == 0)
1364                 return (0);
1365         if (strcasecmp(hexsl, ADMIN_LOW) == 0) {
1366                 /* must be readonly */
1367                 uint64_t rdonly;
1368 
1369                 if (dsl_prop_get_integer(dsname,
1370                     zfs_prop_to_name(ZFS_PROP_READONLY), &rdonly, NULL))
1371                         return (SET_ERROR(EACCES));
1372                 return (rdonly ? 0 : EACCES);
1373         }
1374         return (SET_ERROR(EACCES));
1375 }
1376 
1377 /*
1378  * Determine whether the mount is allowed according to MAC check.
1379  * by comparing (where appropriate) label of the dataset against
1380  * the label of the zone being mounted into.  If the dataset has
1381  * no label, create one.
1382  *
1383  * Returns 0 if access allowed, error otherwise (e.g. EACCES)
1384  */
1385 static int
1386 zfs_mount_label_policy(vfs_t *vfsp, char *osname)
1387 {
1388         int             error, retv;
1389         zone_t          *mntzone = NULL;
1390         ts_label_t      *mnt_tsl;
1391         bslabel_t       *mnt_sl;
1392         bslabel_t       ds_sl;
1393         char            ds_hexsl[MAXNAMELEN];
1394 
1395         retv = EACCES;                          /* assume the worst */
1396 
1397         /*
1398          * Start by getting the dataset label if it exists.
1399          */
1400         error = dsl_prop_get(osname, zfs_prop_to_name(ZFS_PROP_MLSLABEL),
1401             1, sizeof (ds_hexsl), &ds_hexsl, NULL);
1402         if (error)
1403                 return (SET_ERROR(EACCES));
1404 
1405         /*
1406          * If labeling is NOT enabled, then disallow the mount of datasets
1407          * which have a non-default label already.  No other label checks
1408          * are needed.
1409          */
1410         if (!is_system_labeled()) {
1411                 if (strcasecmp(ds_hexsl, ZFS_MLSLABEL_DEFAULT) == 0)
1412                         return (0);
1413                 return (SET_ERROR(EACCES));
1414         }
1415 
1416         /*
1417          * Get the label of the mountpoint.  If mounting into the global
1418          * zone (i.e. mountpoint is not within an active zone and the
1419          * zoned property is off), the label must be default or
1420          * admin_low/admin_high only; no other checks are needed.
1421          */
1422         mntzone = zone_find_by_any_path(refstr_value(vfsp->vfs_mntpt), B_FALSE);
1423         if (mntzone->zone_id == GLOBAL_ZONEID) {
1424                 uint64_t zoned;
1425 
1426                 zone_rele(mntzone);
1427 
1428                 if (dsl_prop_get_integer(osname,
1429                     zfs_prop_to_name(ZFS_PROP_ZONED), &zoned, NULL))
1430                         return (SET_ERROR(EACCES));
1431                 if (!zoned)
1432                         return (zfs_check_global_label(osname, ds_hexsl));
1433                 else
1434                         /*
1435                          * This is the case of a zone dataset being mounted
1436                          * initially, before the zone has been fully created;
1437                          * allow this mount into global zone.
1438                          */
1439                         return (0);
1440         }
1441 
1442         mnt_tsl = mntzone->zone_slabel;
1443         ASSERT(mnt_tsl != NULL);
1444         label_hold(mnt_tsl);
1445         mnt_sl = label2bslabel(mnt_tsl);
1446 
1447         if (strcasecmp(ds_hexsl, ZFS_MLSLABEL_DEFAULT) == 0) {
1448                 /*
1449                  * The dataset doesn't have a real label, so fabricate one.
1450                  */
1451                 char *str = NULL;
1452 
1453                 if (l_to_str_internal(mnt_sl, &str) == 0 &&
1454                     dsl_prop_set_string(osname,
1455                     zfs_prop_to_name(ZFS_PROP_MLSLABEL),
1456                     ZPROP_SRC_LOCAL, str) == 0)
1457                         retv = 0;
1458                 if (str != NULL)
1459                         kmem_free(str, strlen(str) + 1);
1460         } else if (hexstr_to_label(ds_hexsl, &ds_sl) == 0) {
1461                 /*
1462                  * Now compare labels to complete the MAC check.  If the
1463                  * labels are equal then allow access.  If the mountpoint
1464                  * label dominates the dataset label, allow readonly access.
1465                  * Otherwise, access is denied.
1466                  */
1467                 if (blequal(mnt_sl, &ds_sl))
1468                         retv = 0;
1469                 else if (bldominates(mnt_sl, &ds_sl)) {
1470                         vfs_setmntopt(vfsp, MNTOPT_RO, NULL, 0);
1471                         retv = 0;
1472                 }
1473         }
1474 
1475         label_rele(mnt_tsl);
1476         zone_rele(mntzone);
1477         return (retv);
1478 }
1479 
1480 static int
1481 zfs_mountroot(vfs_t *vfsp, enum whymountroot why)
1482 {
1483         int error = 0;
1484         static int zfsrootdone = 0;
1485         zfsvfs_t *zfsvfs = NULL;
1486         znode_t *zp = NULL;
1487         vnode_t *vp = NULL;
1488         char *zfs_bootfs;
1489         char *zfs_devid;
1490 
1491         ASSERT(vfsp);
1492 
1493         /*
1494          * The filesystem that we mount as root is defined in the
1495          * boot property "zfs-bootfs" with a format of
1496          * "poolname/root-dataset-objnum".
1497          */
1498         if (why == ROOT_INIT) {
1499                 if (zfsrootdone++)
1500                         return (SET_ERROR(EBUSY));
1501                 /*
1502                  * the process of doing a spa_load will require the
1503                  * clock to be set before we could (for example) do
1504                  * something better by looking at the timestamp on
1505                  * an uberblock, so just set it to -1.
1506                  */
1507                 clkset(-1);
1508 
1509                 if ((zfs_bootfs = spa_get_bootprop("zfs-bootfs")) == NULL) {
1510                         cmn_err(CE_NOTE, "spa_get_bootfs: can not get "
1511                             "bootfs name");
1512                         return (SET_ERROR(EINVAL));
1513                 }
1514                 zfs_devid = spa_get_bootprop("diskdevid");
1515                 error = spa_import_rootpool(rootfs.bo_name, zfs_devid);
1516                 if (zfs_devid)
1517                         spa_free_bootprop(zfs_devid);
1518                 if (error) {
1519                         spa_free_bootprop(zfs_bootfs);
1520                         cmn_err(CE_NOTE, "spa_import_rootpool: error %d",
1521                             error);
1522                         return (error);
1523                 }
1524                 if (error = zfs_parse_bootfs(zfs_bootfs, rootfs.bo_name)) {
1525                         spa_free_bootprop(zfs_bootfs);
1526                         cmn_err(CE_NOTE, "zfs_parse_bootfs: error %d",
1527                             error);
1528                         return (error);
1529                 }
1530 
1531                 spa_free_bootprop(zfs_bootfs);
1532 
1533                 if (error = vfs_lock(vfsp))
1534                         return (error);
1535 
1536                 if (error = zfs_domount(vfsp, rootfs.bo_name)) {
1537                         cmn_err(CE_NOTE, "zfs_domount: error %d", error);
1538                         goto out;
1539                 }
1540 
1541                 zfsvfs = (zfsvfs_t *)vfsp->vfs_data;
1542                 ASSERT(zfsvfs);
1543                 if (error = zfs_zget(zfsvfs, zfsvfs->z_root, &zp)) {
1544                         cmn_err(CE_NOTE, "zfs_zget: error %d", error);
1545                         goto out;
1546                 }
1547 
1548                 vp = ZTOV(zp);
1549                 mutex_enter(&vp->v_lock);
1550                 vp->v_flag |= VROOT;
1551                 mutex_exit(&vp->v_lock);
1552                 rootvp = vp;
1553 
1554                 /*
1555                  * Leave rootvp held.  The root file system is never unmounted.
1556                  */
1557 
1558                 vfs_add((struct vnode *)0, vfsp,
1559                     (vfsp->vfs_flag & VFS_RDONLY) ? MS_RDONLY : 0);
1560 out:
1561                 vfs_unlock(vfsp);
1562                 return (error);
1563         } else if (why == ROOT_REMOUNT) {
1564                 readonly_changed_cb(vfsp->vfs_data, B_FALSE);
1565                 vfsp->vfs_flag |= VFS_REMOUNT;
1566 
1567                 /* refresh mount options */
1568                 zfs_unregister_callbacks(vfsp->vfs_data);
1569                 return (zfs_register_callbacks(vfsp));
1570 
1571         } else if (why == ROOT_UNMOUNT) {
1572                 zfs_unregister_callbacks((zfsvfs_t *)vfsp->vfs_data);
1573                 (void) zfs_sync(vfsp, 0, 0);
1574                 return (0);
1575         }
1576 
1577         /*
1578          * if "why" is equal to anything else other than ROOT_INIT,
1579          * ROOT_REMOUNT, or ROOT_UNMOUNT, we do not support it.
1580          */
1581         return (SET_ERROR(ENOTSUP));
1582 }
1583 
1584 /*ARGSUSED*/
1585 static int
1586 zfs_mount(vfs_t *vfsp, vnode_t *mvp, struct mounta *uap, cred_t *cr)
1587 {
1588         char            *osname;
1589         pathname_t      spn;
1590         int             error = 0;
1591         uio_seg_t       fromspace = (uap->flags & MS_SYSSPACE) ?
1592             UIO_SYSSPACE : UIO_USERSPACE;
1593         int             canwrite;
1594 
1595         if (mvp->v_type != VDIR)
1596                 return (SET_ERROR(ENOTDIR));
1597 
1598         mutex_enter(&mvp->v_lock);
1599         if ((uap->flags & MS_REMOUNT) == 0 &&
1600             (uap->flags & MS_OVERLAY) == 0 &&
1601             (mvp->v_count != 1 || (mvp->v_flag & VROOT))) {
1602                 mutex_exit(&mvp->v_lock);
1603                 return (SET_ERROR(EBUSY));
1604         }
1605         mutex_exit(&mvp->v_lock);
1606 
1607         /*
1608          * ZFS does not support passing unparsed data in via MS_DATA.
1609          * Users should use the MS_OPTIONSTR interface; this means
1610          * that all option parsing is already done and the options struct
1611          * can be interrogated.
1612          */
1613         if ((uap->flags & MS_DATA) && uap->datalen > 0)
1614                 return (SET_ERROR(EINVAL));
1615 
1616         /*
1617          * Get the objset name (the "special" mount argument).
1618          */
1619         if (error = pn_get(uap->spec, fromspace, &spn))
1620                 return (error);
1621 
1622         osname = spn.pn_path;
1623 
1624         /*
1625          * Check for mount privilege?
1626          *
1627          * If we don't have privilege then see if
1628          * we have local permission to allow it
1629          */
1630         error = secpolicy_fs_mount(cr, mvp, vfsp);
1631         if (error) {
1632                 if (dsl_deleg_access(osname, ZFS_DELEG_PERM_MOUNT, cr) == 0) {
1633                         vattr_t         vattr;
1634 
1635                         /*
1636                          * Make sure user is the owner of the mount point
1637                          * or has sufficient privileges.
1638                          */
1639 
1640                         vattr.va_mask = AT_UID;
1641 
1642                         if (VOP_GETATTR(mvp, &vattr, 0, cr, NULL)) {
1643                                 goto out;
1644                         }
1645 
1646                         if (secpolicy_vnode_owner(cr, vattr.va_uid) != 0 &&
1647                             VOP_ACCESS(mvp, VWRITE, 0, cr, NULL) != 0) {
1648                                 goto out;
1649                         }
1650                         secpolicy_fs_mount_clearopts(cr, vfsp);
1651                 } else {
1652                         goto out;
1653                 }
1654         }
1655 
1656         /*
1657          * Refuse to mount a filesystem if we are in a local zone and the
1658          * dataset is not visible.
1659          */
1660         if (!INGLOBALZONE(curproc) &&
1661             (!zone_dataset_visible(osname, &canwrite) || !canwrite)) {
1662                 error = SET_ERROR(EPERM);
1663                 goto out;
1664         }
1665 
1666         error = zfs_mount_label_policy(vfsp, osname);
1667         if (error)
1668                 goto out;
1669 
1670         /*
1671          * When doing a remount, we simply refresh our temporary properties
1672          * according to those options set in the current VFS options.
1673          */
1674         if (uap->flags & MS_REMOUNT) {
1675                 /* refresh mount options */
1676                 zfs_unregister_callbacks(vfsp->vfs_data);
1677                 error = zfs_register_callbacks(vfsp);
1678                 goto out;
1679         }
1680 
1681         error = zfs_domount(vfsp, osname);
1682 
1683         /*
1684          * Add an extra VFS_HOLD on our parent vfs so that it can't
1685          * disappear due to a forced unmount.
1686          */
1687         if (error == 0 && ((zfsvfs_t *)vfsp->vfs_data)->z_issnap)
1688                 VFS_HOLD(mvp->v_vfsp);
1689 
1690 out:
1691         pn_free(&spn);
1692         return (error);
1693 }
1694 
1695 static int
1696 zfs_statvfs(vfs_t *vfsp, struct statvfs64 *statp)
1697 {
1698         zfsvfs_t *zfsvfs = vfsp->vfs_data;
1699         dev32_t d32;
1700         uint64_t refdbytes, availbytes, usedobjs, availobjs;
1701 
1702         ZFS_ENTER(zfsvfs);
1703 
1704         dmu_objset_space(zfsvfs->z_os,
1705             &refdbytes, &availbytes, &usedobjs, &availobjs);
1706 
1707         /*
1708          * The underlying storage pool actually uses multiple block sizes.
1709          * We report the fragsize as the smallest block size we support,
1710          * and we report our blocksize as the filesystem's maximum blocksize.
1711          */
1712         statp->f_frsize = 1UL << SPA_MINBLOCKSHIFT;
1713         statp->f_bsize = zfsvfs->z_max_blksz;
1714 
1715         /*
1716          * The following report "total" blocks of various kinds in the
1717          * file system, but reported in terms of f_frsize - the
1718          * "fragment" size.
1719          */
1720 
1721         statp->f_blocks = (refdbytes + availbytes) >> SPA_MINBLOCKSHIFT;
1722         statp->f_bfree = availbytes >> SPA_MINBLOCKSHIFT;
1723         statp->f_bavail = statp->f_bfree; /* no root reservation */
1724 
1725         /*
1726          * statvfs() should really be called statufs(), because it assumes
1727          * static metadata.  ZFS doesn't preallocate files, so the best
1728          * we can do is report the max that could possibly fit in f_files,
1729          * and that minus the number actually used in f_ffree.
1730          * For f_ffree, report the smaller of the number of object available
1731          * and the number of blocks (each object will take at least a block).
1732          */
1733         statp->f_ffree = MIN(availobjs, statp->f_bfree);
1734         statp->f_favail = statp->f_ffree; /* no "root reservation" */
1735         statp->f_files = statp->f_ffree + usedobjs;
1736 
1737         (void) cmpldev(&d32, vfsp->vfs_dev);
1738         statp->f_fsid = d32;
1739 
1740         /*
1741          * We're a zfs filesystem.
1742          */
1743         (void) strcpy(statp->f_basetype, vfssw[vfsp->vfs_fstype].vsw_name);
1744 
1745         statp->f_flag = vf_to_stf(vfsp->vfs_flag);
1746 
1747         statp->f_namemax = ZFS_MAXNAMELEN;
1748 
1749         /*
1750          * We have all of 32 characters to stuff a string here.
1751          * Is there anything useful we could/should provide?
1752          */
1753         bzero(statp->f_fstr, sizeof (statp->f_fstr));
1754 
1755         ZFS_EXIT(zfsvfs);
1756         return (0);
1757 }
1758 
1759 static int
1760 zfs_root(vfs_t *vfsp, vnode_t **vpp)
1761 {
1762         zfsvfs_t *zfsvfs = vfsp->vfs_data;
1763         znode_t *rootzp;
1764         int error;
1765 
1766         ZFS_ENTER(zfsvfs);
1767 
1768         error = zfs_zget(zfsvfs, zfsvfs->z_root, &rootzp);
1769         if (error == 0)
1770                 *vpp = ZTOV(rootzp);
1771 
1772         ZFS_EXIT(zfsvfs);
1773         return (error);
1774 }
1775 
1776 /*
1777  * Teardown the zfsvfs::z_os.
1778  *
1779  * Note, if 'unmounting' if FALSE, we return with the 'z_teardown_lock'
1780  * and 'z_teardown_inactive_lock' held.
1781  */
1782 static int
1783 zfsvfs_teardown(zfsvfs_t *zfsvfs, boolean_t unmounting)
1784 {
1785         znode_t *zp;
1786 
1787         rrw_enter(&zfsvfs->z_teardown_lock, RW_WRITER, FTAG);
1788 
1789         if (!unmounting) {
1790                 /*
1791                  * We purge the parent filesystem's vfsp as the parent
1792                  * filesystem and all of its snapshots have their vnode's
1793                  * v_vfsp set to the parent's filesystem's vfsp.  Note,
1794                  * 'z_parent' is self referential for non-snapshots.
1795                  */
1796                 (void) dnlc_purge_vfsp(zfsvfs->z_parent->z_vfs, 0);
1797         }
1798 
1799         /*
1800          * Close the zil. NB: Can't close the zil while zfs_inactive
1801          * threads are blocked as zil_close can call zfs_inactive.
1802          */
1803         if (zfsvfs->z_log) {
1804                 zil_close(zfsvfs->z_log);
1805                 zfsvfs->z_log = NULL;
1806         }
1807 
1808         rw_enter(&zfsvfs->z_teardown_inactive_lock, RW_WRITER);
1809 
1810         /*
1811          * If we are not unmounting (ie: online recv) and someone already
1812          * unmounted this file system while we were doing the switcheroo,
1813          * or a reopen of z_os failed then just bail out now.
1814          */
1815         if (!unmounting && (zfsvfs->z_unmounted || zfsvfs->z_os == NULL)) {
1816                 rw_exit(&zfsvfs->z_teardown_inactive_lock);
1817                 rrw_exit(&zfsvfs->z_teardown_lock, FTAG);
1818                 return (SET_ERROR(EIO));
1819         }
1820 
1821         /*
1822          * At this point there are no vops active, and any new vops will
1823          * fail with EIO since we have z_teardown_lock for writer (only
1824          * relavent for forced unmount).
1825          *
1826          * Release all holds on dbufs.
1827          */
1828         mutex_enter(&zfsvfs->z_znodes_lock);
1829         for (zp = list_head(&zfsvfs->z_all_znodes); zp != NULL;
1830             zp = list_next(&zfsvfs->z_all_znodes, zp))
1831                 if (zp->z_sa_hdl) {
1832                         ASSERT(ZTOV(zp)->v_count > 0);
1833                         zfs_znode_dmu_fini(zp);
1834                 }
1835         mutex_exit(&zfsvfs->z_znodes_lock);
1836 
1837         /*
1838          * If we are unmounting, set the unmounted flag and let new vops
1839          * unblock.  zfs_inactive will have the unmounted behavior, and all
1840          * other vops will fail with EIO.
1841          */
1842         if (unmounting) {
1843                 zfsvfs->z_unmounted = B_TRUE;
1844                 rrw_exit(&zfsvfs->z_teardown_lock, FTAG);
1845                 rw_exit(&zfsvfs->z_teardown_inactive_lock);
1846         }
1847 
1848         /*
1849          * z_os will be NULL if there was an error in attempting to reopen
1850          * zfsvfs, so just return as the properties had already been
1851          * unregistered and cached data had been evicted before.
1852          */
1853         if (zfsvfs->z_os == NULL)
1854                 return (0);
1855 
1856         /*
1857          * Unregister properties.
1858          */
1859         zfs_unregister_callbacks(zfsvfs);
1860 
1861         /*
1862          * Evict cached data
1863          */
1864         if (dsl_dataset_is_dirty(dmu_objset_ds(zfsvfs->z_os)) &&
1865             !(zfsvfs->z_vfs->vfs_flag & VFS_RDONLY))
1866                 txg_wait_synced(dmu_objset_pool(zfsvfs->z_os), 0);
1867         dmu_objset_evict_dbufs(zfsvfs->z_os);
1868 
1869         return (0);
1870 }
1871 
1872 /*ARGSUSED*/
1873 static int
1874 zfs_umount(vfs_t *vfsp, int fflag, cred_t *cr)
1875 {
1876         zfsvfs_t *zfsvfs = vfsp->vfs_data;
1877         objset_t *os;
1878         int ret;
1879 
1880         ret = secpolicy_fs_unmount(cr, vfsp);
1881         if (ret) {
1882                 if (dsl_deleg_access((char *)refstr_value(vfsp->vfs_resource),
1883                     ZFS_DELEG_PERM_MOUNT, cr))
1884                         return (ret);
1885         }
1886 
1887         /*
1888          * We purge the parent filesystem's vfsp as the parent filesystem
1889          * and all of its snapshots have their vnode's v_vfsp set to the
1890          * parent's filesystem's vfsp.  Note, 'z_parent' is self
1891          * referential for non-snapshots.
1892          */
1893         (void) dnlc_purge_vfsp(zfsvfs->z_parent->z_vfs, 0);
1894 
1895         /*
1896          * Unmount any snapshots mounted under .zfs before unmounting the
1897          * dataset itself.
1898          */
1899         if (zfsvfs->z_ctldir != NULL &&
1900             (ret = zfsctl_umount_snapshots(vfsp, fflag, cr)) != 0) {
1901                 return (ret);
1902         }
1903 
1904         if (!(fflag & MS_FORCE)) {
1905                 /*
1906                  * Check the number of active vnodes in the file system.
1907                  * Our count is maintained in the vfs structure, but the
1908                  * number is off by 1 to indicate a hold on the vfs
1909                  * structure itself.
1910                  *
1911                  * The '.zfs' directory maintains a reference of its
1912                  * own, and any active references underneath are
1913                  * reflected in the vnode count.
1914                  */
1915                 if (zfsvfs->z_ctldir == NULL) {
1916                         if (vfsp->vfs_count > 1)
1917                                 return (SET_ERROR(EBUSY));
1918                 } else {
1919                         if (vfsp->vfs_count > 2 ||
1920                             zfsvfs->z_ctldir->v_count > 1)
1921                                 return (SET_ERROR(EBUSY));
1922                 }
1923         }
1924 
1925         vfsp->vfs_flag |= VFS_UNMOUNTED;
1926 
1927         VERIFY(zfsvfs_teardown(zfsvfs, B_TRUE) == 0);
1928         os = zfsvfs->z_os;
1929 
1930         /*
1931          * z_os will be NULL if there was an error in
1932          * attempting to reopen zfsvfs.
1933          */
1934         if (os != NULL) {
1935                 /*
1936                  * Unset the objset user_ptr.
1937                  */
1938                 mutex_enter(&os->os_user_ptr_lock);
1939                 dmu_objset_set_user(os, NULL);
1940                 mutex_exit(&os->os_user_ptr_lock);
1941 
1942                 /*
1943                  * Finally release the objset
1944                  */
1945                 dmu_objset_disown(os, zfsvfs);
1946         }
1947 
1948         /*
1949          * We can now safely destroy the '.zfs' directory node.
1950          */
1951         if (zfsvfs->z_ctldir != NULL)
1952                 zfsctl_destroy(zfsvfs);
1953 
1954         return (0);
1955 }
1956 
1957 static int
1958 zfs_vget(vfs_t *vfsp, vnode_t **vpp, fid_t *fidp)
1959 {
1960         zfsvfs_t        *zfsvfs = vfsp->vfs_data;
1961         znode_t         *zp;
1962         uint64_t        object = 0;
1963         uint64_t        fid_gen = 0;
1964         uint64_t        gen_mask;
1965         uint64_t        zp_gen;
1966         int             i, err;
1967 
1968         *vpp = NULL;
1969 
1970         ZFS_ENTER(zfsvfs);
1971 
1972         if (fidp->fid_len == LONG_FID_LEN) {
1973                 zfid_long_t     *zlfid = (zfid_long_t *)fidp;
1974                 uint64_t        objsetid = 0;
1975                 uint64_t        setgen = 0;
1976 
1977                 for (i = 0; i < sizeof (zlfid->zf_setid); i++)
1978                         objsetid |= ((uint64_t)zlfid->zf_setid[i]) << (8 * i);
1979 
1980                 for (i = 0; i < sizeof (zlfid->zf_setgen); i++)
1981                         setgen |= ((uint64_t)zlfid->zf_setgen[i]) << (8 * i);
1982 
1983                 ZFS_EXIT(zfsvfs);
1984 
1985                 err = zfsctl_lookup_objset(vfsp, objsetid, &zfsvfs);
1986                 if (err)
1987                         return (SET_ERROR(EINVAL));
1988                 ZFS_ENTER(zfsvfs);
1989         }
1990 
1991         if (fidp->fid_len == SHORT_FID_LEN || fidp->fid_len == LONG_FID_LEN) {
1992                 zfid_short_t    *zfid = (zfid_short_t *)fidp;
1993 
1994                 for (i = 0; i < sizeof (zfid->zf_object); i++)
1995                         object |= ((uint64_t)zfid->zf_object[i]) << (8 * i);
1996 
1997                 for (i = 0; i < sizeof (zfid->zf_gen); i++)
1998                         fid_gen |= ((uint64_t)zfid->zf_gen[i]) << (8 * i);
1999         } else {
2000                 ZFS_EXIT(zfsvfs);
2001                 return (SET_ERROR(EINVAL));
2002         }
2003 
2004         /* A zero fid_gen means we are in the .zfs control directories */
2005         if (fid_gen == 0 &&
2006             (object == ZFSCTL_INO_ROOT || object == ZFSCTL_INO_SNAPDIR)) {
2007                 *vpp = zfsvfs->z_ctldir;
2008                 ASSERT(*vpp != NULL);
2009                 if (object == ZFSCTL_INO_SNAPDIR) {
2010                         VERIFY(zfsctl_root_lookup(*vpp, "snapshot", vpp, NULL,
2011                             0, NULL, NULL, NULL, NULL, NULL) == 0);
2012                 } else {
2013                         VN_HOLD(*vpp);
2014                 }
2015                 ZFS_EXIT(zfsvfs);
2016                 return (0);
2017         }
2018 
2019         gen_mask = -1ULL >> (64 - 8 * i);
2020 
2021         dprintf("getting %llu [%u mask %llx]\n", object, fid_gen, gen_mask);
2022         if (err = zfs_zget(zfsvfs, object, &zp)) {
2023                 ZFS_EXIT(zfsvfs);
2024                 return (err);
2025         }
2026         (void) sa_lookup(zp->z_sa_hdl, SA_ZPL_GEN(zfsvfs), &zp_gen,
2027             sizeof (uint64_t));
2028         zp_gen = zp_gen & gen_mask;
2029         if (zp_gen == 0)
2030                 zp_gen = 1;
2031         if (zp->z_unlinked || zp_gen != fid_gen) {
2032                 dprintf("znode gen (%u) != fid gen (%u)\n", zp_gen, fid_gen);
2033                 VN_RELE(ZTOV(zp));
2034                 ZFS_EXIT(zfsvfs);
2035                 return (SET_ERROR(EINVAL));
2036         }
2037 
2038         *vpp = ZTOV(zp);
2039         ZFS_EXIT(zfsvfs);
2040         return (0);
2041 }
2042 
2043 /*
2044  * Block out VOPs and close zfsvfs_t::z_os
2045  *
2046  * Note, if successful, then we return with the 'z_teardown_lock' and
2047  * 'z_teardown_inactive_lock' write held.
2048  */
2049 int
2050 zfs_suspend_fs(zfsvfs_t *zfsvfs)
2051 {
2052         int error;
2053 
2054         if ((error = zfsvfs_teardown(zfsvfs, B_FALSE)) != 0)
2055                 return (error);
2056         dmu_objset_disown(zfsvfs->z_os, zfsvfs);
2057 
2058         return (0);
2059 }
2060 
2061 /*
2062  * Reopen zfsvfs_t::z_os and release VOPs.
2063  */
2064 int
2065 zfs_resume_fs(zfsvfs_t *zfsvfs, const char *osname)
2066 {
2067         int err;
2068 
2069         ASSERT(RRW_WRITE_HELD(&zfsvfs->z_teardown_lock));
2070         ASSERT(RW_WRITE_HELD(&zfsvfs->z_teardown_inactive_lock));
2071 
2072         err = dmu_objset_own(osname, DMU_OST_ZFS, B_FALSE, zfsvfs,
2073             &zfsvfs->z_os);
2074         if (err) {
2075                 zfsvfs->z_os = NULL;
2076         } else {
2077                 znode_t *zp;
2078                 uint64_t sa_obj = 0;
2079 
2080                 /*
2081                  * Make sure version hasn't changed
2082                  */
2083 
2084                 err = zfs_get_zplprop(zfsvfs->z_os, ZFS_PROP_VERSION,
2085                     &zfsvfs->z_version);
2086 
2087                 if (err)
2088                         goto bail;
2089 
2090                 err = zap_lookup(zfsvfs->z_os, MASTER_NODE_OBJ,
2091                     ZFS_SA_ATTRS, 8, 1, &sa_obj);
2092 
2093                 if (err && zfsvfs->z_version >= ZPL_VERSION_SA)
2094                         goto bail;
2095 
2096                 if ((err = sa_setup(zfsvfs->z_os, sa_obj,
2097                     zfs_attr_table,  ZPL_END, &zfsvfs->z_attr_table)) != 0)
2098                         goto bail;
2099 
2100                 if (zfsvfs->z_version >= ZPL_VERSION_SA)
2101                         sa_register_update_callback(zfsvfs->z_os,
2102                             zfs_sa_upgrade);
2103 
2104                 VERIFY(zfsvfs_setup(zfsvfs, B_FALSE) == 0);
2105 
2106                 zfs_set_fuid_feature(zfsvfs);
2107 
2108                 /*
2109                  * Attempt to re-establish all the active znodes with
2110                  * their dbufs.  If a zfs_rezget() fails, then we'll let
2111                  * any potential callers discover that via ZFS_ENTER_VERIFY_VP
2112                  * when they try to use their znode.
2113                  */
2114                 mutex_enter(&zfsvfs->z_znodes_lock);
2115                 for (zp = list_head(&zfsvfs->z_all_znodes); zp;
2116                     zp = list_next(&zfsvfs->z_all_znodes, zp)) {
2117                         (void) zfs_rezget(zp);
2118                 }
2119                 mutex_exit(&zfsvfs->z_znodes_lock);
2120         }
2121 
2122 bail:
2123         /* release the VOPs */
2124         rw_exit(&zfsvfs->z_teardown_inactive_lock);
2125         rrw_exit(&zfsvfs->z_teardown_lock, FTAG);
2126 
2127         if (err) {
2128                 /*
2129                  * Since we couldn't reopen zfsvfs::z_os, or
2130                  * setup the sa framework force unmount this file system.
2131                  */
2132                 if (vn_vfswlock(zfsvfs->z_vfs->vfs_vnodecovered) == 0)
2133                         (void) dounmount(zfsvfs->z_vfs, MS_FORCE, CRED());
2134         }
2135         return (err);
2136 }
2137 
2138 static void
2139 zfs_freevfs(vfs_t *vfsp)
2140 {
2141         zfsvfs_t *zfsvfs = vfsp->vfs_data;
2142 
2143         /*
2144          * If this is a snapshot, we have an extra VFS_HOLD on our parent
2145          * from zfs_mount().  Release it here.  If we came through
2146          * zfs_mountroot() instead, we didn't grab an extra hold, so
2147          * skip the VFS_RELE for rootvfs.
2148          */
2149         if (zfsvfs->z_issnap && (vfsp != rootvfs))
2150                 VFS_RELE(zfsvfs->z_parent->z_vfs);
2151 
2152         zfsvfs_free(zfsvfs);
2153 
2154         atomic_add_32(&zfs_active_fs_count, -1);
2155 }
2156 
2157 /*
2158  * VFS_INIT() initialization.  Note that there is no VFS_FINI(),
2159  * so we can't safely do any non-idempotent initialization here.
2160  * Leave that to zfs_init() and zfs_fini(), which are called
2161  * from the module's _init() and _fini() entry points.
2162  */
2163 /*ARGSUSED*/
2164 static int
2165 zfs_vfsinit(int fstype, char *name)
2166 {
2167         int error;
2168 
2169         zfsfstype = fstype;
2170 
2171         /*
2172          * Setup vfsops and vnodeops tables.
2173          */
2174         error = vfs_setfsops(fstype, zfs_vfsops_template, &zfs_vfsops);
2175         if (error != 0) {
2176                 cmn_err(CE_WARN, "zfs: bad vfs ops template");
2177         }
2178 
2179         error = zfs_create_op_tables();
2180         if (error) {
2181                 zfs_remove_op_tables();
2182                 cmn_err(CE_WARN, "zfs: bad vnode ops template");
2183                 (void) vfs_freevfsops_by_type(zfsfstype);
2184                 return (error);
2185         }
2186 
2187         mutex_init(&zfs_dev_mtx, NULL, MUTEX_DEFAULT, NULL);
2188 
2189         /*
2190          * Unique major number for all zfs mounts.
2191          * If we run out of 32-bit minors, we'll getudev() another major.
2192          */
2193         zfs_major = ddi_name_to_major(ZFS_DRIVER);
2194         zfs_minor = ZFS_MIN_MINOR;
2195 
2196         return (0);
2197 }
2198 
2199 void
2200 zfs_init(void)
2201 {
2202         /*
2203          * Initialize .zfs directory structures
2204          */
2205         zfsctl_init();
2206 
2207         /*
2208          * Initialize znode cache, vnode ops, etc...
2209          */
2210         zfs_znode_init();
2211 
2212         dmu_objset_register_type(DMU_OST_ZFS, zfs_space_delta_cb);
2213 }
2214 
2215 void
2216 zfs_fini(void)
2217 {
2218         zfsctl_fini();
2219         zfs_znode_fini();
2220 }
2221 
2222 int
2223 zfs_busy(void)
2224 {
2225         return (zfs_active_fs_count != 0);
2226 }
2227 
2228 int
2229 zfs_set_version(zfsvfs_t *zfsvfs, uint64_t newvers)
2230 {
2231         int error;
2232         objset_t *os = zfsvfs->z_os;
2233         dmu_tx_t *tx;
2234 
2235         if (newvers < ZPL_VERSION_INITIAL || newvers > ZPL_VERSION)
2236                 return (SET_ERROR(EINVAL));
2237 
2238         if (newvers < zfsvfs->z_version)
2239                 return (SET_ERROR(EINVAL));
2240 
2241         if (zfs_spa_version_map(newvers) >
2242             spa_version(dmu_objset_spa(zfsvfs->z_os)))
2243                 return (SET_ERROR(ENOTSUP));
2244 
2245         tx = dmu_tx_create(os);
2246         dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, B_FALSE, ZPL_VERSION_STR);
2247         if (newvers >= ZPL_VERSION_SA && !zfsvfs->z_use_sa) {
2248                 dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, B_TRUE,
2249                     ZFS_SA_ATTRS);
2250                 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL);
2251         }
2252         error = dmu_tx_assign(tx, TXG_WAIT);
2253         if (error) {
2254                 dmu_tx_abort(tx);
2255                 return (error);
2256         }
2257 
2258         error = zap_update(os, MASTER_NODE_OBJ, ZPL_VERSION_STR,
2259             8, 1, &newvers, tx);
2260 
2261         if (error) {
2262                 dmu_tx_commit(tx);
2263                 return (error);
2264         }
2265 
2266         if (newvers >= ZPL_VERSION_SA && !zfsvfs->z_use_sa) {
2267                 uint64_t sa_obj;
2268 
2269                 ASSERT3U(spa_version(dmu_objset_spa(zfsvfs->z_os)), >=,
2270                     SPA_VERSION_SA);
2271                 sa_obj = zap_create(os, DMU_OT_SA_MASTER_NODE,
2272                     DMU_OT_NONE, 0, tx);
2273 
2274                 error = zap_add(os, MASTER_NODE_OBJ,
2275                     ZFS_SA_ATTRS, 8, 1, &sa_obj, tx);
2276                 ASSERT0(error);
2277 
2278                 VERIFY(0 == sa_set_sa_object(os, sa_obj));
2279                 sa_register_update_callback(os, zfs_sa_upgrade);
2280         }
2281 
2282         spa_history_log_internal_ds(dmu_objset_ds(os), "upgrade", tx,
2283             "from %llu to %llu", zfsvfs->z_version, newvers);
2284 
2285         dmu_tx_commit(tx);
2286 
2287         zfsvfs->z_version = newvers;
2288 
2289         zfs_set_fuid_feature(zfsvfs);
2290 
2291         return (0);
2292 }
2293 
2294 /*
2295  * Read a property stored within the master node.
2296  */
2297 int
2298 zfs_get_zplprop(objset_t *os, zfs_prop_t prop, uint64_t *value)
2299 {
2300         const char *pname;
2301         int error = ENOENT;
2302 
2303         /*
2304          * Look up the file system's value for the property.  For the
2305          * version property, we look up a slightly different string.
2306          */
2307         if (prop == ZFS_PROP_VERSION)
2308                 pname = ZPL_VERSION_STR;
2309         else
2310                 pname = zfs_prop_to_name(prop);
2311 
2312         if (os != NULL)
2313                 error = zap_lookup(os, MASTER_NODE_OBJ, pname, 8, 1, value);
2314 
2315         if (error == ENOENT) {
2316                 /* No value set, use the default value */
2317                 switch (prop) {
2318                 case ZFS_PROP_VERSION:
2319                         *value = ZPL_VERSION;
2320                         break;
2321                 case ZFS_PROP_NORMALIZE:
2322                 case ZFS_PROP_UTF8ONLY:
2323                         *value = 0;
2324                         break;
2325                 case ZFS_PROP_CASE:
2326                         *value = ZFS_CASE_SENSITIVE;
2327                         break;
2328                 default:
2329                         return (error);
2330                 }
2331                 error = 0;
2332         }
2333         return (error);
2334 }
2335 
2336 static vfsdef_t vfw = {
2337         VFSDEF_VERSION,
2338         MNTTYPE_ZFS,
2339         zfs_vfsinit,
2340         VSW_HASPROTO|VSW_CANRWRO|VSW_CANREMOUNT|VSW_VOLATILEDEV|VSW_STATS|
2341             VSW_XID|VSW_ZMOUNT,
2342         &zfs_mntopts
2343 };
2344 
2345 struct modlfs zfs_modlfs = {
2346         &mod_fsops, "ZFS filesystem version " SPA_VERSION_STRING, &vfw
2347 };