xref: /illumos-gate/usr/src/uts/common/fs/zfs/zfs_vfsops.c (revision f67950b21e185934ccabe311516f4dcbdb00ef79)
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) 2012, 2015 by Delphix. All rights reserved.
24  * Copyright (c) 2014 Integros [integros.com]
25  * Copyright 2016 Nexenta Systems, Inc. All rights reserved.
26  * Copyright 2019 Joyent, Inc.
27  */
28 
29 /* Portions Copyright 2010 Robert Milkowski */
30 
31 #include <sys/types.h>
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/sysmacros.h>
35 #include <sys/kmem.h>
36 #include <sys/pathname.h>
37 #include <sys/vnode.h>
38 #include <sys/vfs.h>
39 #include <sys/vfs_opreg.h>
40 #include <sys/mntent.h>
41 #include <sys/mount.h>
42 #include <sys/cmn_err.h>
43 #include "fs/fs_subr.h"
44 #include <sys/zfs_znode.h>
45 #include <sys/zfs_dir.h>
46 #include <sys/zil.h>
47 #include <sys/fs/zfs.h>
48 #include <sys/dmu.h>
49 #include <sys/dsl_prop.h>
50 #include <sys/dsl_dataset.h>
51 #include <sys/dsl_deleg.h>
52 #include <sys/spa.h>
53 #include <sys/zap.h>
54 #include <sys/sa.h>
55 #include <sys/sa_impl.h>
56 #include <sys/varargs.h>
57 #include <sys/policy.h>
58 #include <sys/atomic.h>
59 #include <sys/mkdev.h>
60 #include <sys/modctl.h>
61 #include <sys/refstr.h>
62 #include <sys/zfs_ioctl.h>
63 #include <sys/zfs_ctldir.h>
64 #include <sys/zfs_fuid.h>
65 #include <sys/bootconf.h>
66 #include <sys/sunddi.h>
67 #include <sys/dnlc.h>
68 #include <sys/dmu_objset.h>
69 #include <sys/spa_boot.h>
70 #include "zfs_comutil.h"
71 
72 int zfsfstype;
73 vfsops_t *zfs_vfsops = NULL;
74 static major_t zfs_major;
75 static minor_t zfs_minor;
76 static kmutex_t	zfs_dev_mtx;
77 
78 extern int sys_shutdown;
79 
80 static int zfs_mount(vfs_t *vfsp, vnode_t *mvp, struct mounta *uap, cred_t *cr);
81 static int zfs_umount(vfs_t *vfsp, int fflag, cred_t *cr);
82 static int zfs_mountroot(vfs_t *vfsp, enum whymountroot);
83 static int zfs_root(vfs_t *vfsp, vnode_t **vpp);
84 static int zfs_statvfs(vfs_t *vfsp, struct statvfs64 *statp);
85 static int zfs_vget(vfs_t *vfsp, vnode_t **vpp, fid_t *fidp);
86 static void zfs_freevfs(vfs_t *vfsp);
87 
88 static const fs_operation_def_t zfs_vfsops_template[] = {
89 	VFSNAME_MOUNT,		{ .vfs_mount = zfs_mount },
90 	VFSNAME_MOUNTROOT,	{ .vfs_mountroot = zfs_mountroot },
91 	VFSNAME_UNMOUNT,	{ .vfs_unmount = zfs_umount },
92 	VFSNAME_ROOT,		{ .vfs_root = zfs_root },
93 	VFSNAME_STATVFS,	{ .vfs_statvfs = zfs_statvfs },
94 	VFSNAME_SYNC,		{ .vfs_sync = zfs_sync },
95 	VFSNAME_VGET,		{ .vfs_vget = zfs_vget },
96 	VFSNAME_FREEVFS,	{ .vfs_freevfs = zfs_freevfs },
97 	NULL,			NULL
98 };
99 
100 /*
101  * We need to keep a count of active fs's.
102  * This is necessary to prevent our module
103  * from being unloaded after a umount -f
104  */
105 static uint32_t	zfs_active_fs_count = 0;
106 
107 static char *noatime_cancel[] = { MNTOPT_ATIME, NULL };
108 static char *atime_cancel[] = { MNTOPT_NOATIME, NULL };
109 static char *noxattr_cancel[] = { MNTOPT_XATTR, NULL };
110 static char *xattr_cancel[] = { MNTOPT_NOXATTR, NULL };
111 
112 /*
113  * MO_DEFAULT is not used since the default value is determined
114  * by the equivalent property.
115  */
116 static mntopt_t mntopts[] = {
117 	{ MNTOPT_NOXATTR, noxattr_cancel, NULL, 0, NULL },
118 	{ MNTOPT_XATTR, xattr_cancel, NULL, 0, NULL },
119 	{ MNTOPT_NOATIME, noatime_cancel, NULL, 0, NULL },
120 	{ MNTOPT_ATIME, atime_cancel, NULL, 0, NULL }
121 };
122 
123 static mntopts_t zfs_mntopts = {
124 	sizeof (mntopts) / sizeof (mntopt_t),
125 	mntopts
126 };
127 
128 /*ARGSUSED*/
129 int
130 zfs_sync(vfs_t *vfsp, short flag, cred_t *cr)
131 {
132 	/*
133 	 * Data integrity is job one.  We don't want a compromised kernel
134 	 * writing to the storage pool, so we never sync during panic.
135 	 */
136 	if (panicstr)
137 		return (0);
138 
139 	/*
140 	 * SYNC_ATTR is used by fsflush() to force old filesystems like UFS
141 	 * to sync metadata, which they would otherwise cache indefinitely.
142 	 * Semantically, the only requirement is that the sync be initiated.
143 	 * The DMU syncs out txgs frequently, so there's nothing to do.
144 	 */
145 	if (flag & SYNC_ATTR)
146 		return (0);
147 
148 	if (vfsp != NULL) {
149 		/*
150 		 * Sync a specific filesystem.
151 		 */
152 		zfsvfs_t *zfsvfs = vfsp->vfs_data;
153 		dsl_pool_t *dp;
154 
155 		ZFS_ENTER(zfsvfs);
156 		dp = dmu_objset_pool(zfsvfs->z_os);
157 
158 		/*
159 		 * If the system is shutting down, then skip any
160 		 * filesystems which may exist on a suspended pool.
161 		 */
162 		if (sys_shutdown && spa_suspended(dp->dp_spa)) {
163 			ZFS_EXIT(zfsvfs);
164 			return (0);
165 		}
166 
167 		if (zfsvfs->z_log != NULL)
168 			zil_commit(zfsvfs->z_log, 0);
169 
170 		ZFS_EXIT(zfsvfs);
171 	} else {
172 		/*
173 		 * Sync all ZFS filesystems.  This is what happens when you
174 		 * run sync(1M).  Unlike other filesystems, ZFS honors the
175 		 * request by waiting for all pools to commit all dirty data.
176 		 */
177 		spa_sync_allpools();
178 	}
179 
180 	return (0);
181 }
182 
183 static int
184 zfs_create_unique_device(dev_t *dev)
185 {
186 	major_t new_major;
187 
188 	do {
189 		ASSERT3U(zfs_minor, <=, MAXMIN32);
190 		minor_t start = zfs_minor;
191 		do {
192 			mutex_enter(&zfs_dev_mtx);
193 			if (zfs_minor >= MAXMIN32) {
194 				/*
195 				 * If we're still using the real major
196 				 * keep out of /dev/zfs and /dev/zvol minor
197 				 * number space.  If we're using a getudev()'ed
198 				 * major number, we can use all of its minors.
199 				 */
200 				if (zfs_major == ddi_name_to_major(ZFS_DRIVER))
201 					zfs_minor = ZFS_MIN_MINOR;
202 				else
203 					zfs_minor = 0;
204 			} else {
205 				zfs_minor++;
206 			}
207 			*dev = makedevice(zfs_major, zfs_minor);
208 			mutex_exit(&zfs_dev_mtx);
209 		} while (vfs_devismounted(*dev) && zfs_minor != start);
210 		if (zfs_minor == start) {
211 			/*
212 			 * We are using all ~262,000 minor numbers for the
213 			 * current major number.  Create a new major number.
214 			 */
215 			if ((new_major = getudev()) == (major_t)-1) {
216 				cmn_err(CE_WARN,
217 				    "zfs_mount: Can't get unique major "
218 				    "device number.");
219 				return (-1);
220 			}
221 			mutex_enter(&zfs_dev_mtx);
222 			zfs_major = new_major;
223 			zfs_minor = 0;
224 
225 			mutex_exit(&zfs_dev_mtx);
226 		} else {
227 			break;
228 		}
229 		/* CONSTANTCONDITION */
230 	} while (1);
231 
232 	return (0);
233 }
234 
235 static void
236 atime_changed_cb(void *arg, uint64_t newval)
237 {
238 	zfsvfs_t *zfsvfs = arg;
239 
240 	if (newval == TRUE) {
241 		zfsvfs->z_atime = TRUE;
242 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NOATIME);
243 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_ATIME, NULL, 0);
244 	} else {
245 		zfsvfs->z_atime = FALSE;
246 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_ATIME);
247 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NOATIME, NULL, 0);
248 	}
249 }
250 
251 static void
252 xattr_changed_cb(void *arg, uint64_t newval)
253 {
254 	zfsvfs_t *zfsvfs = arg;
255 
256 	if (newval == TRUE) {
257 		/* XXX locking on vfs_flag? */
258 		zfsvfs->z_vfs->vfs_flag |= VFS_XATTR;
259 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NOXATTR);
260 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_XATTR, NULL, 0);
261 	} else {
262 		/* XXX locking on vfs_flag? */
263 		zfsvfs->z_vfs->vfs_flag &= ~VFS_XATTR;
264 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_XATTR);
265 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NOXATTR, NULL, 0);
266 	}
267 }
268 
269 static void
270 blksz_changed_cb(void *arg, uint64_t newval)
271 {
272 	zfsvfs_t *zfsvfs = arg;
273 	ASSERT3U(newval, <=, spa_maxblocksize(dmu_objset_spa(zfsvfs->z_os)));
274 	ASSERT3U(newval, >=, SPA_MINBLOCKSIZE);
275 	ASSERT(ISP2(newval));
276 
277 	zfsvfs->z_max_blksz = newval;
278 	zfsvfs->z_vfs->vfs_bsize = newval;
279 }
280 
281 static void
282 readonly_changed_cb(void *arg, uint64_t newval)
283 {
284 	zfsvfs_t *zfsvfs = arg;
285 
286 	if (newval) {
287 		/* XXX locking on vfs_flag? */
288 		zfsvfs->z_vfs->vfs_flag |= VFS_RDONLY;
289 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_RW);
290 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_RO, NULL, 0);
291 	} else {
292 		/* XXX locking on vfs_flag? */
293 		zfsvfs->z_vfs->vfs_flag &= ~VFS_RDONLY;
294 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_RO);
295 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_RW, NULL, 0);
296 	}
297 }
298 
299 static void
300 devices_changed_cb(void *arg, uint64_t newval)
301 {
302 	zfsvfs_t *zfsvfs = arg;
303 
304 	if (newval == FALSE) {
305 		zfsvfs->z_vfs->vfs_flag |= VFS_NODEVICES;
306 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_DEVICES);
307 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NODEVICES, NULL, 0);
308 	} else {
309 		zfsvfs->z_vfs->vfs_flag &= ~VFS_NODEVICES;
310 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NODEVICES);
311 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_DEVICES, NULL, 0);
312 	}
313 }
314 
315 static void
316 setuid_changed_cb(void *arg, uint64_t newval)
317 {
318 	zfsvfs_t *zfsvfs = arg;
319 
320 	if (newval == FALSE) {
321 		zfsvfs->z_vfs->vfs_flag |= VFS_NOSETUID;
322 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_SETUID);
323 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NOSETUID, NULL, 0);
324 	} else {
325 		zfsvfs->z_vfs->vfs_flag &= ~VFS_NOSETUID;
326 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NOSETUID);
327 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_SETUID, NULL, 0);
328 	}
329 }
330 
331 static void
332 exec_changed_cb(void *arg, uint64_t newval)
333 {
334 	zfsvfs_t *zfsvfs = arg;
335 
336 	if (newval == FALSE) {
337 		zfsvfs->z_vfs->vfs_flag |= VFS_NOEXEC;
338 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_EXEC);
339 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NOEXEC, NULL, 0);
340 	} else {
341 		zfsvfs->z_vfs->vfs_flag &= ~VFS_NOEXEC;
342 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NOEXEC);
343 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_EXEC, NULL, 0);
344 	}
345 }
346 
347 /*
348  * The nbmand mount option can be changed at mount time.
349  * We can't allow it to be toggled on live file systems or incorrect
350  * behavior may be seen from cifs clients
351  *
352  * This property isn't registered via dsl_prop_register(), but this callback
353  * will be called when a file system is first mounted
354  */
355 static void
356 nbmand_changed_cb(void *arg, uint64_t newval)
357 {
358 	zfsvfs_t *zfsvfs = arg;
359 	if (newval == FALSE) {
360 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NBMAND);
361 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NONBMAND, NULL, 0);
362 	} else {
363 		vfs_clearmntopt(zfsvfs->z_vfs, MNTOPT_NONBMAND);
364 		vfs_setmntopt(zfsvfs->z_vfs, MNTOPT_NBMAND, NULL, 0);
365 	}
366 }
367 
368 static void
369 snapdir_changed_cb(void *arg, uint64_t newval)
370 {
371 	zfsvfs_t *zfsvfs = arg;
372 
373 	zfsvfs->z_show_ctldir = newval;
374 }
375 
376 static void
377 vscan_changed_cb(void *arg, uint64_t newval)
378 {
379 	zfsvfs_t *zfsvfs = arg;
380 
381 	zfsvfs->z_vscan = newval;
382 }
383 
384 static void
385 acl_mode_changed_cb(void *arg, uint64_t newval)
386 {
387 	zfsvfs_t *zfsvfs = arg;
388 
389 	zfsvfs->z_acl_mode = newval;
390 }
391 
392 static void
393 acl_inherit_changed_cb(void *arg, uint64_t newval)
394 {
395 	zfsvfs_t *zfsvfs = arg;
396 
397 	zfsvfs->z_acl_inherit = newval;
398 }
399 
400 static int
401 zfs_register_callbacks(vfs_t *vfsp)
402 {
403 	struct dsl_dataset *ds = NULL;
404 	objset_t *os = NULL;
405 	zfsvfs_t *zfsvfs = NULL;
406 	uint64_t nbmand;
407 	boolean_t readonly = B_FALSE;
408 	boolean_t do_readonly = B_FALSE;
409 	boolean_t setuid = B_FALSE;
410 	boolean_t do_setuid = B_FALSE;
411 	boolean_t exec = B_FALSE;
412 	boolean_t do_exec = B_FALSE;
413 	boolean_t devices = B_FALSE;
414 	boolean_t do_devices = B_FALSE;
415 	boolean_t xattr = B_FALSE;
416 	boolean_t do_xattr = B_FALSE;
417 	boolean_t atime = B_FALSE;
418 	boolean_t do_atime = B_FALSE;
419 	int error = 0;
420 
421 	ASSERT(vfsp);
422 	zfsvfs = vfsp->vfs_data;
423 	ASSERT(zfsvfs);
424 	os = zfsvfs->z_os;
425 
426 	/*
427 	 * The act of registering our callbacks will destroy any mount
428 	 * options we may have.  In order to enable temporary overrides
429 	 * of mount options, we stash away the current values and
430 	 * restore them after we register the callbacks.
431 	 */
432 	if (vfs_optionisset(vfsp, MNTOPT_RO, NULL) ||
433 	    !spa_writeable(dmu_objset_spa(os))) {
434 		readonly = B_TRUE;
435 		do_readonly = B_TRUE;
436 	} else if (vfs_optionisset(vfsp, MNTOPT_RW, NULL)) {
437 		readonly = B_FALSE;
438 		do_readonly = B_TRUE;
439 	}
440 	if (vfs_optionisset(vfsp, MNTOPT_NOSUID, NULL)) {
441 		devices = B_FALSE;
442 		setuid = B_FALSE;
443 		do_devices = B_TRUE;
444 		do_setuid = B_TRUE;
445 	} else {
446 		if (vfs_optionisset(vfsp, MNTOPT_NODEVICES, NULL)) {
447 			devices = B_FALSE;
448 			do_devices = B_TRUE;
449 		} else if (vfs_optionisset(vfsp, MNTOPT_DEVICES, NULL)) {
450 			devices = B_TRUE;
451 			do_devices = B_TRUE;
452 		}
453 
454 		if (vfs_optionisset(vfsp, MNTOPT_NOSETUID, NULL)) {
455 			setuid = B_FALSE;
456 			do_setuid = B_TRUE;
457 		} else if (vfs_optionisset(vfsp, MNTOPT_SETUID, NULL)) {
458 			setuid = B_TRUE;
459 			do_setuid = B_TRUE;
460 		}
461 	}
462 	if (vfs_optionisset(vfsp, MNTOPT_NOEXEC, NULL)) {
463 		exec = B_FALSE;
464 		do_exec = B_TRUE;
465 	} else if (vfs_optionisset(vfsp, MNTOPT_EXEC, NULL)) {
466 		exec = B_TRUE;
467 		do_exec = B_TRUE;
468 	}
469 	if (vfs_optionisset(vfsp, MNTOPT_NOXATTR, NULL)) {
470 		xattr = B_FALSE;
471 		do_xattr = B_TRUE;
472 	} else if (vfs_optionisset(vfsp, MNTOPT_XATTR, NULL)) {
473 		xattr = B_TRUE;
474 		do_xattr = B_TRUE;
475 	}
476 	if (vfs_optionisset(vfsp, MNTOPT_NOATIME, NULL)) {
477 		atime = B_FALSE;
478 		do_atime = B_TRUE;
479 	} else if (vfs_optionisset(vfsp, MNTOPT_ATIME, NULL)) {
480 		atime = B_TRUE;
481 		do_atime = B_TRUE;
482 	}
483 
484 	/*
485 	 * nbmand is a special property.  It can only be changed at
486 	 * mount time.
487 	 *
488 	 * This is weird, but it is documented to only be changeable
489 	 * at mount time.
490 	 */
491 	if (vfs_optionisset(vfsp, MNTOPT_NONBMAND, NULL)) {
492 		nbmand = B_FALSE;
493 	} else if (vfs_optionisset(vfsp, MNTOPT_NBMAND, NULL)) {
494 		nbmand = B_TRUE;
495 	} else {
496 		char osname[ZFS_MAX_DATASET_NAME_LEN];
497 
498 		dmu_objset_name(os, osname);
499 		if (error = dsl_prop_get_integer(osname, "nbmand", &nbmand,
500 		    NULL)) {
501 			return (error);
502 		}
503 	}
504 
505 	/*
506 	 * Register property callbacks.
507 	 *
508 	 * It would probably be fine to just check for i/o error from
509 	 * the first prop_register(), but I guess I like to go
510 	 * overboard...
511 	 */
512 	ds = dmu_objset_ds(os);
513 	dsl_pool_config_enter(dmu_objset_pool(os), FTAG);
514 	error = dsl_prop_register(ds,
515 	    zfs_prop_to_name(ZFS_PROP_ATIME), atime_changed_cb, zfsvfs);
516 	error = error ? error : dsl_prop_register(ds,
517 	    zfs_prop_to_name(ZFS_PROP_XATTR), xattr_changed_cb, zfsvfs);
518 	error = error ? error : dsl_prop_register(ds,
519 	    zfs_prop_to_name(ZFS_PROP_RECORDSIZE), blksz_changed_cb, zfsvfs);
520 	error = error ? error : dsl_prop_register(ds,
521 	    zfs_prop_to_name(ZFS_PROP_READONLY), readonly_changed_cb, zfsvfs);
522 	error = error ? error : dsl_prop_register(ds,
523 	    zfs_prop_to_name(ZFS_PROP_DEVICES), devices_changed_cb, zfsvfs);
524 	error = error ? error : dsl_prop_register(ds,
525 	    zfs_prop_to_name(ZFS_PROP_SETUID), setuid_changed_cb, zfsvfs);
526 	error = error ? error : dsl_prop_register(ds,
527 	    zfs_prop_to_name(ZFS_PROP_EXEC), exec_changed_cb, zfsvfs);
528 	error = error ? error : dsl_prop_register(ds,
529 	    zfs_prop_to_name(ZFS_PROP_SNAPDIR), snapdir_changed_cb, zfsvfs);
530 	error = error ? error : dsl_prop_register(ds,
531 	    zfs_prop_to_name(ZFS_PROP_ACLMODE), acl_mode_changed_cb, zfsvfs);
532 	error = error ? error : dsl_prop_register(ds,
533 	    zfs_prop_to_name(ZFS_PROP_ACLINHERIT), acl_inherit_changed_cb,
534 	    zfsvfs);
535 	error = error ? error : dsl_prop_register(ds,
536 	    zfs_prop_to_name(ZFS_PROP_VSCAN), vscan_changed_cb, zfsvfs);
537 	dsl_pool_config_exit(dmu_objset_pool(os), FTAG);
538 	if (error)
539 		goto unregister;
540 
541 	/*
542 	 * Invoke our callbacks to restore temporary mount options.
543 	 */
544 	if (do_readonly)
545 		readonly_changed_cb(zfsvfs, readonly);
546 	if (do_setuid)
547 		setuid_changed_cb(zfsvfs, setuid);
548 	if (do_exec)
549 		exec_changed_cb(zfsvfs, exec);
550 	if (do_devices)
551 		devices_changed_cb(zfsvfs, devices);
552 	if (do_xattr)
553 		xattr_changed_cb(zfsvfs, xattr);
554 	if (do_atime)
555 		atime_changed_cb(zfsvfs, atime);
556 
557 	nbmand_changed_cb(zfsvfs, nbmand);
558 
559 	return (0);
560 
561 unregister:
562 	dsl_prop_unregister_all(ds, zfsvfs);
563 	return (error);
564 }
565 
566 static int
567 zfs_space_delta_cb(dmu_object_type_t bonustype, void *data,
568     uint64_t *userp, uint64_t *groupp, uint64_t *projectp)
569 {
570 	sa_hdr_phys_t sa;
571 	sa_hdr_phys_t *sap = data;
572 	uint64_t flags;
573 	int hdrsize;
574 	boolean_t swap = B_FALSE;
575 
576 	/*
577 	 * Is it a valid type of object to track?
578 	 */
579 	if (bonustype != DMU_OT_ZNODE && bonustype != DMU_OT_SA)
580 		return (SET_ERROR(ENOENT));
581 
582 	/*
583 	 * If we have a NULL data pointer
584 	 * then assume the id's aren't changing and
585 	 * return EEXIST to the dmu to let it know to
586 	 * use the same ids
587 	 */
588 	if (data == NULL)
589 		return (SET_ERROR(EEXIST));
590 
591 	if (bonustype == DMU_OT_ZNODE) {
592 		znode_phys_t *znp = data;
593 		*userp = znp->zp_uid;
594 		*groupp = znp->zp_gid;
595 		*projectp = ZFS_DEFAULT_PROJID;
596 		return (0);
597 	}
598 
599 	if (sap->sa_magic == 0) {
600 		/*
601 		 * This should only happen for newly created files
602 		 * that haven't had the znode data filled in yet.
603 		 */
604 		*userp = 0;
605 		*groupp = 0;
606 		*projectp = ZFS_DEFAULT_PROJID;
607 		return (0);
608 	}
609 
610 	sa = *sap;
611 	if (sa.sa_magic == BSWAP_32(SA_MAGIC)) {
612 		sa.sa_magic = SA_MAGIC;
613 		sa.sa_layout_info = BSWAP_16(sa.sa_layout_info);
614 		swap = B_TRUE;
615 	} else {
616 		VERIFY3U(sa.sa_magic, ==, SA_MAGIC);
617 	}
618 
619 	hdrsize = sa_hdrsize(&sa);
620 	VERIFY3U(hdrsize, >=, sizeof (sa_hdr_phys_t));
621 
622 	*userp = *((uint64_t *)((uintptr_t)data + hdrsize + SA_UID_OFFSET));
623 	*groupp = *((uint64_t *)((uintptr_t)data + hdrsize + SA_GID_OFFSET));
624 	flags = *((uint64_t *)((uintptr_t)data + hdrsize + SA_FLAGS_OFFSET));
625 	if (swap)
626 		flags = BSWAP_64(flags);
627 
628 	if (flags & ZFS_PROJID)
629 		*projectp = *((uint64_t *)((uintptr_t)data + hdrsize +
630 		    SA_PROJID_OFFSET));
631 	else
632 		*projectp = ZFS_DEFAULT_PROJID;
633 
634 	if (swap) {
635 		*userp = BSWAP_64(*userp);
636 		*groupp = BSWAP_64(*groupp);
637 		*projectp = BSWAP_64(*projectp);
638 	}
639 	return (0);
640 }
641 
642 static void
643 fuidstr_to_sid(zfsvfs_t *zfsvfs, const char *fuidstr,
644     char *domainbuf, int buflen, uid_t *ridp)
645 {
646 	uint64_t fuid;
647 	const char *domain;
648 
649 	fuid = zfs_strtonum(fuidstr, NULL);
650 
651 	domain = zfs_fuid_find_by_idx(zfsvfs, FUID_INDEX(fuid));
652 	if (domain)
653 		(void) strlcpy(domainbuf, domain, buflen);
654 	else
655 		domainbuf[0] = '\0';
656 	*ridp = FUID_RID(fuid);
657 }
658 
659 static uint64_t
660 zfs_userquota_prop_to_obj(zfsvfs_t *zfsvfs, zfs_userquota_prop_t type)
661 {
662 	switch (type) {
663 	case ZFS_PROP_USERUSED:
664 	case ZFS_PROP_USEROBJUSED:
665 		return (DMU_USERUSED_OBJECT);
666 	case ZFS_PROP_GROUPUSED:
667 	case ZFS_PROP_GROUPOBJUSED:
668 		return (DMU_GROUPUSED_OBJECT);
669 	case ZFS_PROP_PROJECTUSED:
670 	case ZFS_PROP_PROJECTOBJUSED:
671 		return (DMU_PROJECTUSED_OBJECT);
672 	case ZFS_PROP_USERQUOTA:
673 		return (zfsvfs->z_userquota_obj);
674 	case ZFS_PROP_GROUPQUOTA:
675 		return (zfsvfs->z_groupquota_obj);
676 	case ZFS_PROP_USEROBJQUOTA:
677 		return (zfsvfs->z_userobjquota_obj);
678 	case ZFS_PROP_GROUPOBJQUOTA:
679 		return (zfsvfs->z_groupobjquota_obj);
680 	case ZFS_PROP_PROJECTQUOTA:
681 		return (zfsvfs->z_projectquota_obj);
682 	case ZFS_PROP_PROJECTOBJQUOTA:
683 		return (zfsvfs->z_projectobjquota_obj);
684 	default:
685 		return (ZFS_NO_OBJECT);
686 	}
687 }
688 
689 int
690 zfs_userspace_many(zfsvfs_t *zfsvfs, zfs_userquota_prop_t type,
691     uint64_t *cookiep, void *vbuf, uint64_t *bufsizep)
692 {
693 	int error;
694 	zap_cursor_t zc;
695 	zap_attribute_t za;
696 	zfs_useracct_t *buf = vbuf;
697 	uint64_t obj;
698 	int offset = 0;
699 
700 	if (!dmu_objset_userspace_present(zfsvfs->z_os))
701 		return (SET_ERROR(ENOTSUP));
702 
703 	if ((type == ZFS_PROP_PROJECTQUOTA || type == ZFS_PROP_PROJECTUSED ||
704 	    type == ZFS_PROP_PROJECTOBJQUOTA ||
705 	    type == ZFS_PROP_PROJECTOBJUSED) &&
706 	    !dmu_objset_projectquota_present(zfsvfs->z_os))
707 		return (SET_ERROR(ENOTSUP));
708 
709 	if ((type == ZFS_PROP_USEROBJUSED || type == ZFS_PROP_GROUPOBJUSED ||
710 	    type == ZFS_PROP_USEROBJQUOTA || type == ZFS_PROP_GROUPOBJQUOTA ||
711 	    type == ZFS_PROP_PROJECTOBJUSED ||
712 	    type == ZFS_PROP_PROJECTOBJQUOTA) &&
713 	    !dmu_objset_userobjspace_present(zfsvfs->z_os))
714 		return (SET_ERROR(ENOTSUP));
715 
716 	obj = zfs_userquota_prop_to_obj(zfsvfs, type);
717 	if (obj == ZFS_NO_OBJECT) {
718 		*bufsizep = 0;
719 		return (0);
720 	}
721 
722 	if (type == ZFS_PROP_USEROBJUSED || type == ZFS_PROP_GROUPOBJUSED ||
723 	    type == ZFS_PROP_PROJECTOBJUSED)
724 		offset = DMU_OBJACCT_PREFIX_LEN;
725 
726 	for (zap_cursor_init_serialized(&zc, zfsvfs->z_os, obj, *cookiep);
727 	    (error = zap_cursor_retrieve(&zc, &za)) == 0;
728 	    zap_cursor_advance(&zc)) {
729 		if ((uintptr_t)buf - (uintptr_t)vbuf + sizeof (zfs_useracct_t) >
730 		    *bufsizep)
731 			break;
732 
733 		/*
734 		 * skip object quota (with zap name prefix DMU_OBJACCT_PREFIX)
735 		 * when dealing with block quota and vice versa.
736 		 */
737 		if ((offset > 0) != (strncmp(za.za_name, DMU_OBJACCT_PREFIX,
738 		    DMU_OBJACCT_PREFIX_LEN) == 0))
739 			continue;
740 
741 		fuidstr_to_sid(zfsvfs, za.za_name + offset,
742 		    buf->zu_domain, sizeof (buf->zu_domain), &buf->zu_rid);
743 
744 		buf->zu_space = za.za_first_integer;
745 		buf++;
746 	}
747 	if (error == ENOENT)
748 		error = 0;
749 
750 	ASSERT3U((uintptr_t)buf - (uintptr_t)vbuf, <=, *bufsizep);
751 	*bufsizep = (uintptr_t)buf - (uintptr_t)vbuf;
752 	*cookiep = zap_cursor_serialize(&zc);
753 	zap_cursor_fini(&zc);
754 	return (error);
755 }
756 
757 /*
758  * buf must be big enough (eg, 32 bytes)
759  */
760 static int
761 id_to_fuidstr(zfsvfs_t *zfsvfs, const char *domain, uid_t rid,
762     char *buf, boolean_t addok)
763 {
764 	uint64_t fuid;
765 	int domainid = 0;
766 
767 	if (domain && domain[0]) {
768 		domainid = zfs_fuid_find_by_domain(zfsvfs, domain, NULL, addok);
769 		if (domainid == -1)
770 			return (SET_ERROR(ENOENT));
771 	}
772 	fuid = FUID_ENCODE(domainid, rid);
773 	(void) sprintf(buf, "%llx", (longlong_t)fuid);
774 	return (0);
775 }
776 
777 int
778 zfs_userspace_one(zfsvfs_t *zfsvfs, zfs_userquota_prop_t type,
779     const char *domain, uint64_t rid, uint64_t *valp)
780 {
781 	char buf[20 + DMU_OBJACCT_PREFIX_LEN];
782 	int offset = 0;
783 	int err;
784 	uint64_t obj;
785 
786 	*valp = 0;
787 
788 	if (!dmu_objset_userspace_present(zfsvfs->z_os))
789 		return (SET_ERROR(ENOTSUP));
790 
791 	if ((type == ZFS_PROP_USEROBJUSED || type == ZFS_PROP_GROUPOBJUSED ||
792 	    type == ZFS_PROP_USEROBJQUOTA || type == ZFS_PROP_GROUPOBJQUOTA ||
793 	    type == ZFS_PROP_PROJECTOBJUSED ||
794 	    type == ZFS_PROP_PROJECTOBJQUOTA) &&
795 	    !dmu_objset_userobjspace_present(zfsvfs->z_os))
796 		return (SET_ERROR(ENOTSUP));
797 
798 	if (type == ZFS_PROP_PROJECTQUOTA || type == ZFS_PROP_PROJECTUSED ||
799 	    type == ZFS_PROP_PROJECTOBJQUOTA ||
800 	    type == ZFS_PROP_PROJECTOBJUSED) {
801 		if (!dmu_objset_projectquota_present(zfsvfs->z_os))
802 			return (SET_ERROR(ENOTSUP));
803 		if (!zpl_is_valid_projid(rid))
804 			return (SET_ERROR(EINVAL));
805 	}
806 
807 	obj = zfs_userquota_prop_to_obj(zfsvfs, type);
808 	if (obj == ZFS_NO_OBJECT)
809 		return (0);
810 
811 	if (type == ZFS_PROP_USEROBJUSED || type == ZFS_PROP_GROUPOBJUSED ||
812 	    type == ZFS_PROP_PROJECTOBJUSED) {
813 		strncpy(buf, DMU_OBJACCT_PREFIX, DMU_OBJACCT_PREFIX_LEN);
814 		offset = DMU_OBJACCT_PREFIX_LEN;
815 	}
816 
817 	err = id_to_fuidstr(zfsvfs, domain, rid, buf + offset, B_FALSE);
818 	if (err)
819 		return (err);
820 
821 	err = zap_lookup(zfsvfs->z_os, obj, buf, 8, 1, valp);
822 	if (err == ENOENT)
823 		err = 0;
824 	return (err);
825 }
826 
827 int
828 zfs_set_userquota(zfsvfs_t *zfsvfs, zfs_userquota_prop_t type,
829     const char *domain, uint64_t rid, uint64_t quota)
830 {
831 	char buf[32];
832 	int err;
833 	dmu_tx_t *tx;
834 	uint64_t *objp;
835 	boolean_t fuid_dirtied;
836 
837 	if (zfsvfs->z_version < ZPL_VERSION_USERSPACE)
838 		return (SET_ERROR(ENOTSUP));
839 
840 	switch (type) {
841 	case ZFS_PROP_USERQUOTA:
842 		objp = &zfsvfs->z_userquota_obj;
843 		break;
844 	case ZFS_PROP_GROUPQUOTA:
845 		objp = &zfsvfs->z_groupquota_obj;
846 		break;
847 	case ZFS_PROP_USEROBJQUOTA:
848 		objp = &zfsvfs->z_userobjquota_obj;
849 		break;
850 	case ZFS_PROP_GROUPOBJQUOTA:
851 		objp = &zfsvfs->z_groupobjquota_obj;
852 		break;
853 	case ZFS_PROP_PROJECTQUOTA:
854 		if (!dmu_objset_projectquota_enabled(zfsvfs->z_os))
855 			return (SET_ERROR(ENOTSUP));
856 		if (!zpl_is_valid_projid(rid))
857 			return (SET_ERROR(EINVAL));
858 
859 		objp = &zfsvfs->z_projectquota_obj;
860 		break;
861 	case ZFS_PROP_PROJECTOBJQUOTA:
862 		if (!dmu_objset_projectquota_enabled(zfsvfs->z_os))
863 			return (SET_ERROR(ENOTSUP));
864 		if (!zpl_is_valid_projid(rid))
865 			return (SET_ERROR(EINVAL));
866 
867 		objp = &zfsvfs->z_projectobjquota_obj;
868 		break;
869 	default:
870 		return (SET_ERROR(EINVAL));
871 	}
872 
873 	err = id_to_fuidstr(zfsvfs, domain, rid, buf, B_TRUE);
874 	if (err)
875 		return (err);
876 	fuid_dirtied = zfsvfs->z_fuid_dirty;
877 
878 	tx = dmu_tx_create(zfsvfs->z_os);
879 	dmu_tx_hold_zap(tx, *objp ? *objp : DMU_NEW_OBJECT, B_TRUE, NULL);
880 	if (*objp == 0) {
881 		dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, B_TRUE,
882 		    zfs_userquota_prop_prefixes[type]);
883 	}
884 	if (fuid_dirtied)
885 		zfs_fuid_txhold(zfsvfs, tx);
886 	err = dmu_tx_assign(tx, TXG_WAIT);
887 	if (err) {
888 		dmu_tx_abort(tx);
889 		return (err);
890 	}
891 
892 	mutex_enter(&zfsvfs->z_lock);
893 	if (*objp == 0) {
894 		*objp = zap_create(zfsvfs->z_os, DMU_OT_USERGROUP_QUOTA,
895 		    DMU_OT_NONE, 0, tx);
896 		VERIFY(0 == zap_add(zfsvfs->z_os, MASTER_NODE_OBJ,
897 		    zfs_userquota_prop_prefixes[type], 8, 1, objp, tx));
898 	}
899 	mutex_exit(&zfsvfs->z_lock);
900 
901 	if (quota == 0) {
902 		err = zap_remove(zfsvfs->z_os, *objp, buf, tx);
903 		if (err == ENOENT)
904 			err = 0;
905 	} else {
906 		err = zap_update(zfsvfs->z_os, *objp, buf, 8, 1, &quota, tx);
907 	}
908 	ASSERT(err == 0);
909 	if (fuid_dirtied)
910 		zfs_fuid_sync(zfsvfs, tx);
911 	dmu_tx_commit(tx);
912 	return (err);
913 }
914 
915 boolean_t
916 zfs_id_overobjquota(zfsvfs_t *zfsvfs, uint64_t usedobj, uint64_t id)
917 {
918 	char buf[20 + DMU_OBJACCT_PREFIX_LEN];
919 	uint64_t used, quota, quotaobj;
920 	int err;
921 
922 	if (!dmu_objset_userobjspace_present(zfsvfs->z_os)) {
923 		if (dmu_objset_userobjspace_upgradable(zfsvfs->z_os))
924 			dmu_objset_id_quota_upgrade(zfsvfs->z_os);
925 		return (B_FALSE);
926 	}
927 
928 	if (usedobj == DMU_PROJECTUSED_OBJECT) {
929 		if (!dmu_objset_projectquota_present(zfsvfs->z_os)) {
930 			if (dmu_objset_projectquota_upgradable(zfsvfs->z_os)) {
931 				dsl_pool_config_enter(
932 				    dmu_objset_pool(zfsvfs->z_os), FTAG);
933 				dmu_objset_id_quota_upgrade(zfsvfs->z_os);
934 				dsl_pool_config_exit(
935 				    dmu_objset_pool(zfsvfs->z_os), FTAG);
936 			}
937 			return (B_FALSE);
938 		}
939 		quotaobj = zfsvfs->z_projectobjquota_obj;
940 	} else if (usedobj == DMU_USERUSED_OBJECT) {
941 		quotaobj = zfsvfs->z_userobjquota_obj;
942 	} else if (usedobj == DMU_GROUPUSED_OBJECT) {
943 		quotaobj = zfsvfs->z_groupobjquota_obj;
944 	} else {
945 		return (B_FALSE);
946 	}
947 	if (quotaobj == 0 || zfsvfs->z_replay)
948 		return (B_FALSE);
949 
950 	(void) sprintf(buf, "%llx", (longlong_t)id);
951 	err = zap_lookup(zfsvfs->z_os, quotaobj, buf, 8, 1, &quota);
952 	if (err != 0)
953 		return (B_FALSE);
954 
955 	(void) sprintf(buf, DMU_OBJACCT_PREFIX "%llx", (longlong_t)id);
956 	err = zap_lookup(zfsvfs->z_os, usedobj, buf, 8, 1, &used);
957 	if (err != 0)
958 		return (B_FALSE);
959 	return (used >= quota);
960 }
961 
962 boolean_t
963 zfs_id_overblockquota(zfsvfs_t *zfsvfs, uint64_t usedobj, uint64_t id)
964 {
965 	char buf[20];
966 	uint64_t used, quota, quotaobj;
967 	int err;
968 
969 	if (usedobj == DMU_PROJECTUSED_OBJECT) {
970 		if (!dmu_objset_projectquota_present(zfsvfs->z_os)) {
971 			if (dmu_objset_projectquota_upgradable(zfsvfs->z_os)) {
972 				dsl_pool_config_enter(
973 				    dmu_objset_pool(zfsvfs->z_os), FTAG);
974 				dmu_objset_id_quota_upgrade(zfsvfs->z_os);
975 				dsl_pool_config_exit(
976 				    dmu_objset_pool(zfsvfs->z_os), FTAG);
977 			}
978 			return (B_FALSE);
979 		}
980 		quotaobj = zfsvfs->z_projectquota_obj;
981 	} else if (usedobj == DMU_USERUSED_OBJECT) {
982 		quotaobj = zfsvfs->z_userquota_obj;
983 	} else if (usedobj == DMU_GROUPUSED_OBJECT) {
984 		quotaobj = zfsvfs->z_groupquota_obj;
985 	} else {
986 		return (B_FALSE);
987 	}
988 	if (quotaobj == 0 || zfsvfs->z_replay)
989 		return (B_FALSE);
990 
991 	(void) sprintf(buf, "%llx", (longlong_t)id);
992 	err = zap_lookup(zfsvfs->z_os, quotaobj, buf, 8, 1, &quota);
993 	if (err != 0)
994 		return (B_FALSE);
995 
996 	err = zap_lookup(zfsvfs->z_os, usedobj, buf, 8, 1, &used);
997 	if (err != 0)
998 		return (B_FALSE);
999 	return (used >= quota);
1000 }
1001 
1002 boolean_t
1003 zfs_id_overquota(zfsvfs_t *zfsvfs, uint64_t usedobj, uint64_t id)
1004 {
1005 	return (zfs_id_overblockquota(zfsvfs, usedobj, id) ||
1006 	    zfs_id_overobjquota(zfsvfs, usedobj, id));
1007 }
1008 
1009 /*
1010  * Associate this zfsvfs with the given objset, which must be owned.
1011  * This will cache a bunch of on-disk state from the objset in the
1012  * zfsvfs.
1013  */
1014 static int
1015 zfsvfs_init(zfsvfs_t *zfsvfs, objset_t *os)
1016 {
1017 	int error;
1018 	uint64_t val;
1019 
1020 	zfsvfs->z_max_blksz = SPA_OLD_MAXBLOCKSIZE;
1021 	zfsvfs->z_show_ctldir = ZFS_SNAPDIR_VISIBLE;
1022 	zfsvfs->z_os = os;
1023 
1024 	error = zfs_get_zplprop(os, ZFS_PROP_VERSION, &zfsvfs->z_version);
1025 	if (error != 0)
1026 		return (error);
1027 	if (zfsvfs->z_version >
1028 	    zfs_zpl_version_map(spa_version(dmu_objset_spa(os)))) {
1029 		(void) printf("Can't mount a version %lld file system "
1030 		    "on a version %lld pool\n. Pool must be upgraded to mount "
1031 		    "this file system.", (u_longlong_t)zfsvfs->z_version,
1032 		    (u_longlong_t)spa_version(dmu_objset_spa(os)));
1033 		return (SET_ERROR(ENOTSUP));
1034 	}
1035 	error = zfs_get_zplprop(os, ZFS_PROP_NORMALIZE, &val);
1036 	if (error != 0)
1037 		return (error);
1038 	zfsvfs->z_norm = (int)val;
1039 
1040 	error = zfs_get_zplprop(os, ZFS_PROP_UTF8ONLY, &val);
1041 	if (error != 0)
1042 		return (error);
1043 	zfsvfs->z_utf8 = (val != 0);
1044 
1045 	error = zfs_get_zplprop(os, ZFS_PROP_CASE, &val);
1046 	if (error != 0)
1047 		return (error);
1048 	zfsvfs->z_case = (uint_t)val;
1049 
1050 	/*
1051 	 * Fold case on file systems that are always or sometimes case
1052 	 * insensitive.
1053 	 */
1054 	if (zfsvfs->z_case == ZFS_CASE_INSENSITIVE ||
1055 	    zfsvfs->z_case == ZFS_CASE_MIXED)
1056 		zfsvfs->z_norm |= U8_TEXTPREP_TOUPPER;
1057 
1058 	zfsvfs->z_use_fuids = USE_FUIDS(zfsvfs->z_version, zfsvfs->z_os);
1059 	zfsvfs->z_use_sa = USE_SA(zfsvfs->z_version, zfsvfs->z_os);
1060 
1061 	uint64_t sa_obj = 0;
1062 	if (zfsvfs->z_use_sa) {
1063 		/* should either have both of these objects or none */
1064 		error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_SA_ATTRS, 8, 1,
1065 		    &sa_obj);
1066 		if (error != 0)
1067 			return (error);
1068 	}
1069 
1070 	error = sa_setup(os, sa_obj, zfs_attr_table, ZPL_END,
1071 	    &zfsvfs->z_attr_table);
1072 	if (error != 0)
1073 		return (error);
1074 
1075 	if (zfsvfs->z_version >= ZPL_VERSION_SA)
1076 		sa_register_update_callback(os, zfs_sa_upgrade);
1077 
1078 	error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_ROOT_OBJ, 8, 1,
1079 	    &zfsvfs->z_root);
1080 	if (error != 0)
1081 		return (error);
1082 	ASSERT(zfsvfs->z_root != 0);
1083 
1084 	error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_UNLINKED_SET, 8, 1,
1085 	    &zfsvfs->z_unlinkedobj);
1086 	if (error != 0)
1087 		return (error);
1088 
1089 	error = zap_lookup(os, MASTER_NODE_OBJ,
1090 	    zfs_userquota_prop_prefixes[ZFS_PROP_USERQUOTA],
1091 	    8, 1, &zfsvfs->z_userquota_obj);
1092 	if (error == ENOENT)
1093 		zfsvfs->z_userquota_obj = 0;
1094 	else if (error != 0)
1095 		return (error);
1096 
1097 	error = zap_lookup(os, MASTER_NODE_OBJ,
1098 	    zfs_userquota_prop_prefixes[ZFS_PROP_GROUPQUOTA],
1099 	    8, 1, &zfsvfs->z_groupquota_obj);
1100 	if (error == ENOENT)
1101 		zfsvfs->z_groupquota_obj = 0;
1102 	else if (error != 0)
1103 		return (error);
1104 
1105 	error = zap_lookup(os, MASTER_NODE_OBJ,
1106 	    zfs_userquota_prop_prefixes[ZFS_PROP_PROJECTQUOTA],
1107 	    8, 1, &zfsvfs->z_projectquota_obj);
1108 	if (error == ENOENT)
1109 		zfsvfs->z_projectquota_obj = 0;
1110 	else if (error != 0)
1111 		return (error);
1112 
1113 	error = zap_lookup(os, MASTER_NODE_OBJ,
1114 	    zfs_userquota_prop_prefixes[ZFS_PROP_USEROBJQUOTA],
1115 	    8, 1, &zfsvfs->z_userobjquota_obj);
1116 	if (error == ENOENT)
1117 		zfsvfs->z_userobjquota_obj = 0;
1118 	else if (error != 0)
1119 		return (error);
1120 
1121 	error = zap_lookup(os, MASTER_NODE_OBJ,
1122 	    zfs_userquota_prop_prefixes[ZFS_PROP_GROUPOBJQUOTA],
1123 	    8, 1, &zfsvfs->z_groupobjquota_obj);
1124 	if (error == ENOENT)
1125 		zfsvfs->z_groupobjquota_obj = 0;
1126 	else if (error != 0)
1127 		return (error);
1128 
1129 	error = zap_lookup(os, MASTER_NODE_OBJ,
1130 	    zfs_userquota_prop_prefixes[ZFS_PROP_PROJECTOBJQUOTA],
1131 	    8, 1, &zfsvfs->z_projectobjquota_obj);
1132 	if (error == ENOENT)
1133 		zfsvfs->z_projectobjquota_obj = 0;
1134 	else if (error != 0)
1135 		return (error);
1136 
1137 	error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_FUID_TABLES, 8, 1,
1138 	    &zfsvfs->z_fuid_obj);
1139 	if (error == ENOENT)
1140 		zfsvfs->z_fuid_obj = 0;
1141 	else if (error != 0)
1142 		return (error);
1143 
1144 	error = zap_lookup(os, MASTER_NODE_OBJ, ZFS_SHARES_DIR, 8, 1,
1145 	    &zfsvfs->z_shares_dir);
1146 	if (error == ENOENT)
1147 		zfsvfs->z_shares_dir = 0;
1148 	else if (error != 0)
1149 		return (error);
1150 
1151 	return (0);
1152 }
1153 
1154 int
1155 zfsvfs_create(const char *osname, zfsvfs_t **zfvp)
1156 {
1157 	objset_t *os;
1158 	zfsvfs_t *zfsvfs;
1159 	int error;
1160 	boolean_t ro = (strchr(osname, '@') != NULL);
1161 
1162 	zfsvfs = kmem_zalloc(sizeof (zfsvfs_t), KM_SLEEP);
1163 
1164 	error = dmu_objset_own(osname, DMU_OST_ZFS, ro, B_TRUE, zfsvfs, &os);
1165 	if (error != 0) {
1166 		kmem_free(zfsvfs, sizeof (zfsvfs_t));
1167 		return (error);
1168 	}
1169 
1170 	error = zfsvfs_create_impl(zfvp, zfsvfs, os);
1171 	if (error != 0) {
1172 		dmu_objset_disown(os, B_TRUE, zfsvfs);
1173 	}
1174 	return (error);
1175 }
1176 
1177 
1178 int
1179 zfsvfs_create_impl(zfsvfs_t **zfvp, zfsvfs_t *zfsvfs, objset_t *os)
1180 {
1181 	int error;
1182 
1183 	zfsvfs->z_vfs = NULL;
1184 	zfsvfs->z_parent = zfsvfs;
1185 
1186 	mutex_init(&zfsvfs->z_znodes_lock, NULL, MUTEX_DEFAULT, NULL);
1187 	mutex_init(&zfsvfs->z_lock, NULL, MUTEX_DEFAULT, NULL);
1188 	list_create(&zfsvfs->z_all_znodes, sizeof (znode_t),
1189 	    offsetof(znode_t, z_link_node));
1190 	rrm_init(&zfsvfs->z_teardown_lock, B_FALSE);
1191 	rw_init(&zfsvfs->z_teardown_inactive_lock, NULL, RW_DEFAULT, NULL);
1192 	rw_init(&zfsvfs->z_fuid_lock, NULL, RW_DEFAULT, NULL);
1193 	for (int i = 0; i != ZFS_OBJ_MTX_SZ; i++)
1194 		mutex_init(&zfsvfs->z_hold_mtx[i], NULL, MUTEX_DEFAULT, NULL);
1195 
1196 	error = zfsvfs_init(zfsvfs, os);
1197 	if (error != 0) {
1198 		*zfvp = NULL;
1199 		kmem_free(zfsvfs, sizeof (zfsvfs_t));
1200 		return (error);
1201 	}
1202 
1203 	*zfvp = zfsvfs;
1204 	return (0);
1205 }
1206 
1207 static int
1208 zfsvfs_setup(zfsvfs_t *zfsvfs, boolean_t mounting)
1209 {
1210 	int error;
1211 
1212 	error = zfs_register_callbacks(zfsvfs->z_vfs);
1213 	if (error)
1214 		return (error);
1215 
1216 	zfsvfs->z_log = zil_open(zfsvfs->z_os, zfs_get_data);
1217 
1218 	/*
1219 	 * If we are not mounting (ie: online recv), then we don't
1220 	 * have to worry about replaying the log as we blocked all
1221 	 * operations out since we closed the ZIL.
1222 	 */
1223 	if (mounting) {
1224 		boolean_t readonly;
1225 
1226 		/*
1227 		 * During replay we remove the read only flag to
1228 		 * allow replays to succeed.
1229 		 */
1230 		readonly = zfsvfs->z_vfs->vfs_flag & VFS_RDONLY;
1231 		if (readonly != 0)
1232 			zfsvfs->z_vfs->vfs_flag &= ~VFS_RDONLY;
1233 		else
1234 			zfs_unlinked_drain(zfsvfs);
1235 
1236 		/*
1237 		 * Parse and replay the intent log.
1238 		 *
1239 		 * Because of ziltest, this must be done after
1240 		 * zfs_unlinked_drain().  (Further note: ziltest
1241 		 * doesn't use readonly mounts, where
1242 		 * zfs_unlinked_drain() isn't called.)  This is because
1243 		 * ziltest causes spa_sync() to think it's committed,
1244 		 * but actually it is not, so the intent log contains
1245 		 * many txg's worth of changes.
1246 		 *
1247 		 * In particular, if object N is in the unlinked set in
1248 		 * the last txg to actually sync, then it could be
1249 		 * actually freed in a later txg and then reallocated
1250 		 * in a yet later txg.  This would write a "create
1251 		 * object N" record to the intent log.  Normally, this
1252 		 * would be fine because the spa_sync() would have
1253 		 * written out the fact that object N is free, before
1254 		 * we could write the "create object N" intent log
1255 		 * record.
1256 		 *
1257 		 * But when we are in ziltest mode, we advance the "open
1258 		 * txg" without actually spa_sync()-ing the changes to
1259 		 * disk.  So we would see that object N is still
1260 		 * allocated and in the unlinked set, and there is an
1261 		 * intent log record saying to allocate it.
1262 		 */
1263 		if (spa_writeable(dmu_objset_spa(zfsvfs->z_os))) {
1264 			if (zil_replay_disable) {
1265 				zil_destroy(zfsvfs->z_log, B_FALSE);
1266 			} else {
1267 				zfsvfs->z_replay = B_TRUE;
1268 				zil_replay(zfsvfs->z_os, zfsvfs,
1269 				    zfs_replay_vector);
1270 				zfsvfs->z_replay = B_FALSE;
1271 			}
1272 		}
1273 
1274 		/* restore readonly bit */
1275 		if (readonly != 0)
1276 			zfsvfs->z_vfs->vfs_flag |= VFS_RDONLY;
1277 	}
1278 
1279 	/*
1280 	 * Set the objset user_ptr to track its zfsvfs.
1281 	 */
1282 	mutex_enter(&zfsvfs->z_os->os_user_ptr_lock);
1283 	dmu_objset_set_user(zfsvfs->z_os, zfsvfs);
1284 	mutex_exit(&zfsvfs->z_os->os_user_ptr_lock);
1285 
1286 	return (0);
1287 }
1288 
1289 void
1290 zfsvfs_free(zfsvfs_t *zfsvfs)
1291 {
1292 	int i;
1293 	extern krwlock_t zfsvfs_lock; /* in zfs_znode.c */
1294 
1295 	/*
1296 	 * This is a barrier to prevent the filesystem from going away in
1297 	 * zfs_znode_move() until we can safely ensure that the filesystem is
1298 	 * not unmounted. We consider the filesystem valid before the barrier
1299 	 * and invalid after the barrier.
1300 	 */
1301 	rw_enter(&zfsvfs_lock, RW_READER);
1302 	rw_exit(&zfsvfs_lock);
1303 
1304 	zfs_fuid_destroy(zfsvfs);
1305 
1306 	mutex_destroy(&zfsvfs->z_znodes_lock);
1307 	mutex_destroy(&zfsvfs->z_lock);
1308 	list_destroy(&zfsvfs->z_all_znodes);
1309 	rrm_destroy(&zfsvfs->z_teardown_lock);
1310 	rw_destroy(&zfsvfs->z_teardown_inactive_lock);
1311 	rw_destroy(&zfsvfs->z_fuid_lock);
1312 	for (i = 0; i != ZFS_OBJ_MTX_SZ; i++)
1313 		mutex_destroy(&zfsvfs->z_hold_mtx[i]);
1314 	kmem_free(zfsvfs, sizeof (zfsvfs_t));
1315 }
1316 
1317 static void
1318 zfs_set_fuid_feature(zfsvfs_t *zfsvfs)
1319 {
1320 	zfsvfs->z_use_fuids = USE_FUIDS(zfsvfs->z_version, zfsvfs->z_os);
1321 	if (zfsvfs->z_vfs) {
1322 		if (zfsvfs->z_use_fuids) {
1323 			vfs_set_feature(zfsvfs->z_vfs, VFSFT_XVATTR);
1324 			vfs_set_feature(zfsvfs->z_vfs, VFSFT_SYSATTR_VIEWS);
1325 			vfs_set_feature(zfsvfs->z_vfs, VFSFT_ACEMASKONACCESS);
1326 			vfs_set_feature(zfsvfs->z_vfs, VFSFT_ACLONCREATE);
1327 			vfs_set_feature(zfsvfs->z_vfs, VFSFT_ACCESS_FILTER);
1328 			vfs_set_feature(zfsvfs->z_vfs, VFSFT_REPARSE);
1329 		} else {
1330 			vfs_clear_feature(zfsvfs->z_vfs, VFSFT_XVATTR);
1331 			vfs_clear_feature(zfsvfs->z_vfs, VFSFT_SYSATTR_VIEWS);
1332 			vfs_clear_feature(zfsvfs->z_vfs, VFSFT_ACEMASKONACCESS);
1333 			vfs_clear_feature(zfsvfs->z_vfs, VFSFT_ACLONCREATE);
1334 			vfs_clear_feature(zfsvfs->z_vfs, VFSFT_ACCESS_FILTER);
1335 			vfs_clear_feature(zfsvfs->z_vfs, VFSFT_REPARSE);
1336 		}
1337 	}
1338 	zfsvfs->z_use_sa = USE_SA(zfsvfs->z_version, zfsvfs->z_os);
1339 }
1340 
1341 static int
1342 zfs_domount(vfs_t *vfsp, char *osname)
1343 {
1344 	dev_t mount_dev;
1345 	uint64_t recordsize, fsid_guid;
1346 	int error = 0;
1347 	zfsvfs_t *zfsvfs;
1348 
1349 	ASSERT(vfsp);
1350 	ASSERT(osname);
1351 
1352 	error = zfsvfs_create(osname, &zfsvfs);
1353 	if (error)
1354 		return (error);
1355 	zfsvfs->z_vfs = vfsp;
1356 
1357 	/* Initialize the generic filesystem structure. */
1358 	vfsp->vfs_bcount = 0;
1359 	vfsp->vfs_data = NULL;
1360 
1361 	if (zfs_create_unique_device(&mount_dev) == -1) {
1362 		error = SET_ERROR(ENODEV);
1363 		goto out;
1364 	}
1365 	ASSERT(vfs_devismounted(mount_dev) == 0);
1366 
1367 	if (error = dsl_prop_get_integer(osname, "recordsize", &recordsize,
1368 	    NULL))
1369 		goto out;
1370 
1371 	vfsp->vfs_dev = mount_dev;
1372 	vfsp->vfs_fstype = zfsfstype;
1373 	vfsp->vfs_bsize = recordsize;
1374 	vfsp->vfs_flag |= VFS_NOTRUNC;
1375 	vfsp->vfs_data = zfsvfs;
1376 
1377 	/*
1378 	 * The fsid is 64 bits, composed of an 8-bit fs type, which
1379 	 * separates our fsid from any other filesystem types, and a
1380 	 * 56-bit objset unique ID.  The objset unique ID is unique to
1381 	 * all objsets open on this system, provided by unique_create().
1382 	 * The 8-bit fs type must be put in the low bits of fsid[1]
1383 	 * because that's where other Solaris filesystems put it.
1384 	 */
1385 	fsid_guid = dmu_objset_fsid_guid(zfsvfs->z_os);
1386 	ASSERT((fsid_guid & ~((1ULL<<56)-1)) == 0);
1387 	vfsp->vfs_fsid.val[0] = fsid_guid;
1388 	vfsp->vfs_fsid.val[1] = ((fsid_guid>>32) << 8) |
1389 	    zfsfstype & 0xFF;
1390 
1391 	/*
1392 	 * Set features for file system.
1393 	 */
1394 	zfs_set_fuid_feature(zfsvfs);
1395 	if (zfsvfs->z_case == ZFS_CASE_INSENSITIVE) {
1396 		vfs_set_feature(vfsp, VFSFT_DIRENTFLAGS);
1397 		vfs_set_feature(vfsp, VFSFT_CASEINSENSITIVE);
1398 		vfs_set_feature(vfsp, VFSFT_NOCASESENSITIVE);
1399 	} else if (zfsvfs->z_case == ZFS_CASE_MIXED) {
1400 		vfs_set_feature(vfsp, VFSFT_DIRENTFLAGS);
1401 		vfs_set_feature(vfsp, VFSFT_CASEINSENSITIVE);
1402 	}
1403 	vfs_set_feature(vfsp, VFSFT_ZEROCOPY_SUPPORTED);
1404 
1405 	if (dmu_objset_is_snapshot(zfsvfs->z_os)) {
1406 		uint64_t pval;
1407 
1408 		atime_changed_cb(zfsvfs, B_FALSE);
1409 		readonly_changed_cb(zfsvfs, B_TRUE);
1410 		if (error = dsl_prop_get_integer(osname, "xattr", &pval, NULL))
1411 			goto out;
1412 		xattr_changed_cb(zfsvfs, pval);
1413 		zfsvfs->z_issnap = B_TRUE;
1414 		zfsvfs->z_os->os_sync = ZFS_SYNC_DISABLED;
1415 
1416 		mutex_enter(&zfsvfs->z_os->os_user_ptr_lock);
1417 		dmu_objset_set_user(zfsvfs->z_os, zfsvfs);
1418 		mutex_exit(&zfsvfs->z_os->os_user_ptr_lock);
1419 	} else {
1420 		error = zfsvfs_setup(zfsvfs, B_TRUE);
1421 	}
1422 
1423 	if (!zfsvfs->z_issnap)
1424 		zfsctl_create(zfsvfs);
1425 out:
1426 	if (error) {
1427 		dmu_objset_disown(zfsvfs->z_os, B_TRUE, zfsvfs);
1428 		zfsvfs_free(zfsvfs);
1429 	} else {
1430 		atomic_inc_32(&zfs_active_fs_count);
1431 	}
1432 
1433 	return (error);
1434 }
1435 
1436 void
1437 zfs_unregister_callbacks(zfsvfs_t *zfsvfs)
1438 {
1439 	objset_t *os = zfsvfs->z_os;
1440 
1441 	if (!dmu_objset_is_snapshot(os))
1442 		dsl_prop_unregister_all(dmu_objset_ds(os), zfsvfs);
1443 }
1444 
1445 /*
1446  * Convert a decimal digit string to a uint64_t integer.
1447  */
1448 static int
1449 str_to_uint64(char *str, uint64_t *objnum)
1450 {
1451 	uint64_t num = 0;
1452 
1453 	while (*str) {
1454 		if (*str < '0' || *str > '9')
1455 			return (SET_ERROR(EINVAL));
1456 
1457 		num = num*10 + *str++ - '0';
1458 	}
1459 
1460 	*objnum = num;
1461 	return (0);
1462 }
1463 
1464 /*
1465  * The boot path passed from the boot loader is in the form of
1466  * "rootpool-name/root-filesystem-object-number'. Convert this
1467  * string to a dataset name: "rootpool-name/root-filesystem-name".
1468  */
1469 static int
1470 zfs_parse_bootfs(char *bpath, char *outpath)
1471 {
1472 	char *slashp;
1473 	uint64_t objnum;
1474 	int error;
1475 
1476 	if (*bpath == 0 || *bpath == '/')
1477 		return (SET_ERROR(EINVAL));
1478 
1479 	(void) strcpy(outpath, bpath);
1480 
1481 	slashp = strchr(bpath, '/');
1482 
1483 	/* if no '/', just return the pool name */
1484 	if (slashp == NULL) {
1485 		return (0);
1486 	}
1487 
1488 	/* if not a number, just return the root dataset name */
1489 	if (str_to_uint64(slashp+1, &objnum)) {
1490 		return (0);
1491 	}
1492 
1493 	*slashp = '\0';
1494 	error = dsl_dsobj_to_dsname(bpath, objnum, outpath);
1495 	*slashp = '/';
1496 
1497 	return (error);
1498 }
1499 
1500 /*
1501  * Check that the hex label string is appropriate for the dataset being
1502  * mounted into the global_zone proper.
1503  *
1504  * Return an error if the hex label string is not default or
1505  * admin_low/admin_high.  For admin_low labels, the corresponding
1506  * dataset must be readonly.
1507  */
1508 int
1509 zfs_check_global_label(const char *dsname, const char *hexsl)
1510 {
1511 	if (strcasecmp(hexsl, ZFS_MLSLABEL_DEFAULT) == 0)
1512 		return (0);
1513 	if (strcasecmp(hexsl, ADMIN_HIGH) == 0)
1514 		return (0);
1515 	if (strcasecmp(hexsl, ADMIN_LOW) == 0) {
1516 		/* must be readonly */
1517 		uint64_t rdonly;
1518 
1519 		if (dsl_prop_get_integer(dsname,
1520 		    zfs_prop_to_name(ZFS_PROP_READONLY), &rdonly, NULL))
1521 			return (SET_ERROR(EACCES));
1522 		return (rdonly ? 0 : EACCES);
1523 	}
1524 	return (SET_ERROR(EACCES));
1525 }
1526 
1527 static int
1528 zfs_statfs_project(zfsvfs_t *zfsvfs, znode_t *zp, struct statvfs64 *statp,
1529     uint32_t bshift)
1530 {
1531 	char buf[20 + DMU_OBJACCT_PREFIX_LEN];
1532 	uint64_t offset = DMU_OBJACCT_PREFIX_LEN;
1533 	uint64_t quota;
1534 	uint64_t used;
1535 	int err;
1536 
1537 	strlcpy(buf, DMU_OBJACCT_PREFIX, DMU_OBJACCT_PREFIX_LEN + 1);
1538 	err = id_to_fuidstr(zfsvfs, NULL, zp->z_projid, buf + offset, B_FALSE);
1539 	if (err)
1540 		return (err);
1541 
1542 	if (zfsvfs->z_projectquota_obj == 0)
1543 		goto objs;
1544 
1545 	err = zap_lookup(zfsvfs->z_os, zfsvfs->z_projectquota_obj,
1546 	    buf + offset, 8, 1, &quota);
1547 	if (err == ENOENT)
1548 		goto objs;
1549 	else if (err)
1550 		return (err);
1551 
1552 	err = zap_lookup(zfsvfs->z_os, DMU_PROJECTUSED_OBJECT,
1553 	    buf + offset, 8, 1, &used);
1554 	if (unlikely(err == ENOENT)) {
1555 		uint32_t blksize;
1556 		u_longlong_t nblocks;
1557 
1558 		/*
1559 		 * Quota accounting is async, so it is possible race case.
1560 		 * There is at least one object with the given project ID.
1561 		 */
1562 		sa_object_size(zp->z_sa_hdl, &blksize, &nblocks);
1563 		if (unlikely(zp->z_blksz == 0))
1564 			blksize = zfsvfs->z_max_blksz;
1565 
1566 		used = blksize * nblocks;
1567 	} else if (err) {
1568 		return (err);
1569 	}
1570 
1571 	statp->f_blocks = quota >> bshift;
1572 	statp->f_bfree = (quota > used) ? ((quota - used) >> bshift) : 0;
1573 	statp->f_bavail = statp->f_bfree;
1574 
1575 objs:
1576 	if (zfsvfs->z_projectobjquota_obj == 0)
1577 		return (0);
1578 
1579 	err = zap_lookup(zfsvfs->z_os, zfsvfs->z_projectobjquota_obj,
1580 	    buf + offset, 8, 1, &quota);
1581 	if (err == ENOENT)
1582 		return (0);
1583 	else if (err)
1584 		return (err);
1585 
1586 	err = zap_lookup(zfsvfs->z_os, DMU_PROJECTUSED_OBJECT,
1587 	    buf, 8, 1, &used);
1588 	if (unlikely(err == ENOENT)) {
1589 		/*
1590 		 * Quota accounting is async, so it is possible race case.
1591 		 * There is at least one object with the given project ID.
1592 		 */
1593 		used = 1;
1594 	} else if (err) {
1595 		return (err);
1596 	}
1597 
1598 	statp->f_files = quota;
1599 	statp->f_ffree = (quota > used) ? (quota - used) : 0;
1600 
1601 	return (0);
1602 }
1603 
1604 /*
1605  * Determine whether the mount is allowed according to MAC check.
1606  * by comparing (where appropriate) label of the dataset against
1607  * the label of the zone being mounted into.  If the dataset has
1608  * no label, create one.
1609  *
1610  * Returns 0 if access allowed, error otherwise (e.g. EACCES)
1611  */
1612 static int
1613 zfs_mount_label_policy(vfs_t *vfsp, char *osname)
1614 {
1615 	int		error, retv;
1616 	zone_t		*mntzone = NULL;
1617 	ts_label_t	*mnt_tsl;
1618 	bslabel_t	*mnt_sl;
1619 	bslabel_t	ds_sl;
1620 	char		ds_hexsl[MAXNAMELEN];
1621 
1622 	retv = EACCES;				/* assume the worst */
1623 
1624 	/*
1625 	 * Start by getting the dataset label if it exists.
1626 	 */
1627 	error = dsl_prop_get(osname, zfs_prop_to_name(ZFS_PROP_MLSLABEL),
1628 	    1, sizeof (ds_hexsl), &ds_hexsl, NULL);
1629 	if (error)
1630 		return (SET_ERROR(EACCES));
1631 
1632 	/*
1633 	 * If labeling is NOT enabled, then disallow the mount of datasets
1634 	 * which have a non-default label already.  No other label checks
1635 	 * are needed.
1636 	 */
1637 	if (!is_system_labeled()) {
1638 		if (strcasecmp(ds_hexsl, ZFS_MLSLABEL_DEFAULT) == 0)
1639 			return (0);
1640 		return (SET_ERROR(EACCES));
1641 	}
1642 
1643 	/*
1644 	 * Get the label of the mountpoint.  If mounting into the global
1645 	 * zone (i.e. mountpoint is not within an active zone and the
1646 	 * zoned property is off), the label must be default or
1647 	 * admin_low/admin_high only; no other checks are needed.
1648 	 */
1649 	mntzone = zone_find_by_any_path(refstr_value(vfsp->vfs_mntpt), B_FALSE);
1650 	if (mntzone->zone_id == GLOBAL_ZONEID) {
1651 		uint64_t zoned;
1652 
1653 		zone_rele(mntzone);
1654 
1655 		if (dsl_prop_get_integer(osname,
1656 		    zfs_prop_to_name(ZFS_PROP_ZONED), &zoned, NULL))
1657 			return (SET_ERROR(EACCES));
1658 		if (!zoned)
1659 			return (zfs_check_global_label(osname, ds_hexsl));
1660 		else
1661 			/*
1662 			 * This is the case of a zone dataset being mounted
1663 			 * initially, before the zone has been fully created;
1664 			 * allow this mount into global zone.
1665 			 */
1666 			return (0);
1667 	}
1668 
1669 	mnt_tsl = mntzone->zone_slabel;
1670 	ASSERT(mnt_tsl != NULL);
1671 	label_hold(mnt_tsl);
1672 	mnt_sl = label2bslabel(mnt_tsl);
1673 
1674 	if (strcasecmp(ds_hexsl, ZFS_MLSLABEL_DEFAULT) == 0) {
1675 		/*
1676 		 * The dataset doesn't have a real label, so fabricate one.
1677 		 */
1678 		char *str = NULL;
1679 
1680 		if (l_to_str_internal(mnt_sl, &str) == 0 &&
1681 		    dsl_prop_set_string(osname,
1682 		    zfs_prop_to_name(ZFS_PROP_MLSLABEL),
1683 		    ZPROP_SRC_LOCAL, str) == 0)
1684 			retv = 0;
1685 		if (str != NULL)
1686 			kmem_free(str, strlen(str) + 1);
1687 	} else if (hexstr_to_label(ds_hexsl, &ds_sl) == 0) {
1688 		/*
1689 		 * Now compare labels to complete the MAC check.  If the
1690 		 * labels are equal then allow access.  If the mountpoint
1691 		 * label dominates the dataset label, allow readonly access.
1692 		 * Otherwise, access is denied.
1693 		 */
1694 		if (blequal(mnt_sl, &ds_sl))
1695 			retv = 0;
1696 		else if (bldominates(mnt_sl, &ds_sl)) {
1697 			vfs_setmntopt(vfsp, MNTOPT_RO, NULL, 0);
1698 			retv = 0;
1699 		}
1700 	}
1701 
1702 	label_rele(mnt_tsl);
1703 	zone_rele(mntzone);
1704 	return (retv);
1705 }
1706 
1707 static int
1708 zfs_mountroot(vfs_t *vfsp, enum whymountroot why)
1709 {
1710 	int error = 0;
1711 	static int zfsrootdone = 0;
1712 	zfsvfs_t *zfsvfs = NULL;
1713 	znode_t *zp = NULL;
1714 	vnode_t *vp = NULL;
1715 	char *zfs_bootfs;
1716 	char *zfs_devid;
1717 
1718 	ASSERT(vfsp);
1719 
1720 	/*
1721 	 * The filesystem that we mount as root is defined in the
1722 	 * boot property "zfs-bootfs" with a format of
1723 	 * "poolname/root-dataset-objnum".
1724 	 */
1725 	if (why == ROOT_INIT) {
1726 		if (zfsrootdone++)
1727 			return (SET_ERROR(EBUSY));
1728 		/*
1729 		 * the process of doing a spa_load will require the
1730 		 * clock to be set before we could (for example) do
1731 		 * something better by looking at the timestamp on
1732 		 * an uberblock, so just set it to -1.
1733 		 */
1734 		clkset(-1);
1735 
1736 		if ((zfs_bootfs = spa_get_bootprop("zfs-bootfs")) == NULL) {
1737 			cmn_err(CE_NOTE, "spa_get_bootfs: can not get "
1738 			    "bootfs name");
1739 			return (SET_ERROR(EINVAL));
1740 		}
1741 		zfs_devid = spa_get_bootprop("diskdevid");
1742 		error = spa_import_rootpool(rootfs.bo_name, zfs_devid);
1743 		if (zfs_devid)
1744 			spa_free_bootprop(zfs_devid);
1745 		if (error) {
1746 			spa_free_bootprop(zfs_bootfs);
1747 			cmn_err(CE_NOTE, "spa_import_rootpool: error %d",
1748 			    error);
1749 			return (error);
1750 		}
1751 		if (error = zfs_parse_bootfs(zfs_bootfs, rootfs.bo_name)) {
1752 			spa_free_bootprop(zfs_bootfs);
1753 			cmn_err(CE_NOTE, "zfs_parse_bootfs: error %d",
1754 			    error);
1755 			return (error);
1756 		}
1757 
1758 		spa_free_bootprop(zfs_bootfs);
1759 
1760 		if (error = vfs_lock(vfsp))
1761 			return (error);
1762 
1763 		if (error = zfs_domount(vfsp, rootfs.bo_name)) {
1764 			cmn_err(CE_NOTE, "zfs_domount: error %d", error);
1765 			goto out;
1766 		}
1767 
1768 		zfsvfs = (zfsvfs_t *)vfsp->vfs_data;
1769 		ASSERT(zfsvfs);
1770 		if (error = zfs_zget(zfsvfs, zfsvfs->z_root, &zp)) {
1771 			cmn_err(CE_NOTE, "zfs_zget: error %d", error);
1772 			goto out;
1773 		}
1774 
1775 		vp = ZTOV(zp);
1776 		mutex_enter(&vp->v_lock);
1777 		vp->v_flag |= VROOT;
1778 		mutex_exit(&vp->v_lock);
1779 		rootvp = vp;
1780 
1781 		/*
1782 		 * Leave rootvp held.  The root file system is never unmounted.
1783 		 */
1784 
1785 		vfs_add((struct vnode *)0, vfsp,
1786 		    (vfsp->vfs_flag & VFS_RDONLY) ? MS_RDONLY : 0);
1787 out:
1788 		vfs_unlock(vfsp);
1789 		return (error);
1790 	} else if (why == ROOT_REMOUNT) {
1791 		readonly_changed_cb(vfsp->vfs_data, B_FALSE);
1792 		vfsp->vfs_flag |= VFS_REMOUNT;
1793 
1794 		/* refresh mount options */
1795 		zfs_unregister_callbacks(vfsp->vfs_data);
1796 		return (zfs_register_callbacks(vfsp));
1797 
1798 	} else if (why == ROOT_UNMOUNT) {
1799 		zfs_unregister_callbacks((zfsvfs_t *)vfsp->vfs_data);
1800 		(void) zfs_sync(vfsp, 0, 0);
1801 		return (0);
1802 	}
1803 
1804 	/*
1805 	 * if "why" is equal to anything else other than ROOT_INIT,
1806 	 * ROOT_REMOUNT, or ROOT_UNMOUNT, we do not support it.
1807 	 */
1808 	return (SET_ERROR(ENOTSUP));
1809 }
1810 
1811 /*ARGSUSED*/
1812 static int
1813 zfs_mount(vfs_t *vfsp, vnode_t *mvp, struct mounta *uap, cred_t *cr)
1814 {
1815 	char		*osname;
1816 	pathname_t	spn;
1817 	int		error = 0;
1818 	uio_seg_t	fromspace = (uap->flags & MS_SYSSPACE) ?
1819 	    UIO_SYSSPACE : UIO_USERSPACE;
1820 	int		canwrite;
1821 
1822 	if (mvp->v_type != VDIR)
1823 		return (SET_ERROR(ENOTDIR));
1824 
1825 	mutex_enter(&mvp->v_lock);
1826 	if ((uap->flags & MS_REMOUNT) == 0 &&
1827 	    (uap->flags & MS_OVERLAY) == 0 &&
1828 	    (mvp->v_count != 1 || (mvp->v_flag & VROOT))) {
1829 		mutex_exit(&mvp->v_lock);
1830 		return (SET_ERROR(EBUSY));
1831 	}
1832 	mutex_exit(&mvp->v_lock);
1833 
1834 	/*
1835 	 * ZFS does not support passing unparsed data in via MS_DATA.
1836 	 * Users should use the MS_OPTIONSTR interface; this means
1837 	 * that all option parsing is already done and the options struct
1838 	 * can be interrogated.
1839 	 */
1840 	if ((uap->flags & MS_DATA) && uap->datalen > 0)
1841 		return (SET_ERROR(EINVAL));
1842 
1843 	/*
1844 	 * Get the objset name (the "special" mount argument).
1845 	 */
1846 	if (error = pn_get(uap->spec, fromspace, &spn))
1847 		return (error);
1848 
1849 	osname = spn.pn_path;
1850 
1851 	/*
1852 	 * Check for mount privilege?
1853 	 *
1854 	 * If we don't have privilege then see if
1855 	 * we have local permission to allow it
1856 	 */
1857 	error = secpolicy_fs_mount(cr, mvp, vfsp);
1858 	if (error) {
1859 		if (dsl_deleg_access(osname, ZFS_DELEG_PERM_MOUNT, cr) == 0) {
1860 			vattr_t		vattr;
1861 
1862 			/*
1863 			 * Make sure user is the owner of the mount point
1864 			 * or has sufficient privileges.
1865 			 */
1866 
1867 			vattr.va_mask = AT_UID;
1868 
1869 			if (VOP_GETATTR(mvp, &vattr, 0, cr, NULL)) {
1870 				goto out;
1871 			}
1872 
1873 			if (secpolicy_vnode_owner(cr, vattr.va_uid) != 0 &&
1874 			    VOP_ACCESS(mvp, VWRITE, 0, cr, NULL) != 0) {
1875 				goto out;
1876 			}
1877 			secpolicy_fs_mount_clearopts(cr, vfsp);
1878 		} else {
1879 			goto out;
1880 		}
1881 	}
1882 
1883 	/*
1884 	 * Refuse to mount a filesystem if we are in a local zone and the
1885 	 * dataset is not visible.
1886 	 */
1887 	if (!INGLOBALZONE(curproc) &&
1888 	    (!zone_dataset_visible(osname, &canwrite) || !canwrite)) {
1889 		error = SET_ERROR(EPERM);
1890 		goto out;
1891 	}
1892 
1893 	error = zfs_mount_label_policy(vfsp, osname);
1894 	if (error)
1895 		goto out;
1896 
1897 	/*
1898 	 * When doing a remount, we simply refresh our temporary properties
1899 	 * according to those options set in the current VFS options.
1900 	 */
1901 	if (uap->flags & MS_REMOUNT) {
1902 		/* refresh mount options */
1903 		zfs_unregister_callbacks(vfsp->vfs_data);
1904 		error = zfs_register_callbacks(vfsp);
1905 		goto out;
1906 	}
1907 
1908 	error = zfs_domount(vfsp, osname);
1909 
1910 	/*
1911 	 * Add an extra VFS_HOLD on our parent vfs so that it can't
1912 	 * disappear due to a forced unmount.
1913 	 */
1914 	if (error == 0 && ((zfsvfs_t *)vfsp->vfs_data)->z_issnap)
1915 		VFS_HOLD(mvp->v_vfsp);
1916 
1917 out:
1918 	pn_free(&spn);
1919 	return (error);
1920 }
1921 
1922 static int
1923 zfs_statvfs(vfs_t *vfsp, struct statvfs64 *statp)
1924 {
1925 	zfsvfs_t *zfsvfs = vfsp->vfs_data;
1926 	dev32_t d32;
1927 	uint64_t refdbytes, availbytes, usedobjs, availobjs;
1928 	int err = 0;
1929 
1930 	ZFS_ENTER(zfsvfs);
1931 
1932 	dmu_objset_space(zfsvfs->z_os,
1933 	    &refdbytes, &availbytes, &usedobjs, &availobjs);
1934 
1935 	/*
1936 	 * The underlying storage pool actually uses multiple block sizes.
1937 	 * We report the fragsize as the smallest block size we support,
1938 	 * and we report our blocksize as the filesystem's maximum blocksize.
1939 	 */
1940 	statp->f_frsize = 1UL << SPA_MINBLOCKSHIFT;
1941 	statp->f_bsize = zfsvfs->z_max_blksz;
1942 
1943 	/*
1944 	 * The following report "total" blocks of various kinds in the
1945 	 * file system, but reported in terms of f_frsize - the
1946 	 * "fragment" size.
1947 	 */
1948 
1949 	statp->f_blocks = (refdbytes + availbytes) >> SPA_MINBLOCKSHIFT;
1950 	statp->f_bfree = availbytes >> SPA_MINBLOCKSHIFT;
1951 	statp->f_bavail = statp->f_bfree; /* no root reservation */
1952 
1953 	/*
1954 	 * statvfs() should really be called statufs(), because it assumes
1955 	 * static metadata.  ZFS doesn't preallocate files, so the best
1956 	 * we can do is report the max that could possibly fit in f_files,
1957 	 * and that minus the number actually used in f_ffree.
1958 	 * For f_ffree, report the smaller of the number of object available
1959 	 * and the number of blocks (each object will take at least a block).
1960 	 */
1961 	statp->f_ffree = MIN(availobjs, statp->f_bfree);
1962 	statp->f_favail = statp->f_ffree;	/* no "root reservation" */
1963 	statp->f_files = statp->f_ffree + usedobjs;
1964 
1965 	(void) cmpldev(&d32, vfsp->vfs_dev);
1966 	statp->f_fsid = d32;
1967 
1968 	/*
1969 	 * We're a zfs filesystem.
1970 	 */
1971 	(void) strcpy(statp->f_basetype, vfssw[vfsp->vfs_fstype].vsw_name);
1972 
1973 	statp->f_flag = vf_to_stf(vfsp->vfs_flag);
1974 
1975 	statp->f_namemax = MAXNAMELEN - 1;
1976 
1977 	/*
1978 	 * We have all of 32 characters to stuff a string here.
1979 	 * Is there anything useful we could/should provide?
1980 	 */
1981 	bzero(statp->f_fstr, sizeof (statp->f_fstr));
1982 
1983 	if (dmu_objset_projectquota_enabled(zfsvfs->z_os) &&
1984 	    dmu_objset_projectquota_present(zfsvfs->z_os)) {
1985 		znode_t *zp;
1986 
1987 		/*
1988 		 * In ZoL, zfs_statvfs is passed a Linux dentry (directory
1989 		 * entry), instead of a vfsp. The ZoL code uses the dentry
1990 		 * to get the znode from the dentry's inode. This represents
1991 		 * whatever filename was passed to the user-level statvfs
1992 		 * syscall.
1993 		 *
1994 		 * We're using the VFS root znode here, so this represents a
1995 		 * potential difference from ZoL.
1996 		 */
1997 		if (zfs_zget(zfsvfs, zfsvfs->z_root, &zp) == 0) {
1998 			uint32_t bshift = ddi_fls(statp->f_bsize) - 1;
1999 
2000 			if (zp->z_pflags & ZFS_PROJINHERIT && zp->z_projid &&
2001 			    zpl_is_valid_projid(zp->z_projid))
2002 				err = zfs_statfs_project(zfsvfs, zp, statp,
2003 				    bshift);
2004 			VN_RELE(ZTOV(zp));
2005 		}
2006 	}
2007 
2008 	ZFS_EXIT(zfsvfs);
2009 	return (err);
2010 }
2011 
2012 static int
2013 zfs_root(vfs_t *vfsp, vnode_t **vpp)
2014 {
2015 	zfsvfs_t *zfsvfs = vfsp->vfs_data;
2016 	znode_t *rootzp;
2017 	int error;
2018 
2019 	ZFS_ENTER(zfsvfs);
2020 
2021 	error = zfs_zget(zfsvfs, zfsvfs->z_root, &rootzp);
2022 	if (error == 0)
2023 		*vpp = ZTOV(rootzp);
2024 
2025 	ZFS_EXIT(zfsvfs);
2026 	return (error);
2027 }
2028 
2029 /*
2030  * Teardown the zfsvfs::z_os.
2031  *
2032  * Note, if 'unmounting' is FALSE, we return with the 'z_teardown_lock'
2033  * and 'z_teardown_inactive_lock' held.
2034  */
2035 static int
2036 zfsvfs_teardown(zfsvfs_t *zfsvfs, boolean_t unmounting)
2037 {
2038 	znode_t	*zp;
2039 
2040 	rrm_enter(&zfsvfs->z_teardown_lock, RW_WRITER, FTAG);
2041 
2042 	if (!unmounting) {
2043 		/*
2044 		 * We purge the parent filesystem's vfsp as the parent
2045 		 * filesystem and all of its snapshots have their vnode's
2046 		 * v_vfsp set to the parent's filesystem's vfsp.  Note,
2047 		 * 'z_parent' is self referential for non-snapshots.
2048 		 */
2049 		(void) dnlc_purge_vfsp(zfsvfs->z_parent->z_vfs, 0);
2050 	}
2051 
2052 	/*
2053 	 * Close the zil. NB: Can't close the zil while zfs_inactive
2054 	 * threads are blocked as zil_close can call zfs_inactive.
2055 	 */
2056 	if (zfsvfs->z_log) {
2057 		zil_close(zfsvfs->z_log);
2058 		zfsvfs->z_log = NULL;
2059 	}
2060 
2061 	rw_enter(&zfsvfs->z_teardown_inactive_lock, RW_WRITER);
2062 
2063 	/*
2064 	 * If we are not unmounting (ie: online recv) and someone already
2065 	 * unmounted this file system while we were doing the switcheroo,
2066 	 * or a reopen of z_os failed then just bail out now.
2067 	 */
2068 	if (!unmounting && (zfsvfs->z_unmounted || zfsvfs->z_os == NULL)) {
2069 		rw_exit(&zfsvfs->z_teardown_inactive_lock);
2070 		rrm_exit(&zfsvfs->z_teardown_lock, FTAG);
2071 		return (SET_ERROR(EIO));
2072 	}
2073 
2074 	/*
2075 	 * At this point there are no vops active, and any new vops will
2076 	 * fail with EIO since we have z_teardown_lock for writer (only
2077 	 * relavent for forced unmount).
2078 	 *
2079 	 * Release all holds on dbufs.
2080 	 */
2081 	mutex_enter(&zfsvfs->z_znodes_lock);
2082 	for (zp = list_head(&zfsvfs->z_all_znodes); zp != NULL;
2083 	    zp = list_next(&zfsvfs->z_all_znodes, zp))
2084 		if (zp->z_sa_hdl) {
2085 			ASSERT(ZTOV(zp)->v_count > 0);
2086 			zfs_znode_dmu_fini(zp);
2087 		}
2088 	mutex_exit(&zfsvfs->z_znodes_lock);
2089 
2090 	/*
2091 	 * If we are unmounting, set the unmounted flag and let new vops
2092 	 * unblock.  zfs_inactive will have the unmounted behavior, and all
2093 	 * other vops will fail with EIO.
2094 	 */
2095 	if (unmounting) {
2096 		zfsvfs->z_unmounted = B_TRUE;
2097 		rw_exit(&zfsvfs->z_teardown_inactive_lock);
2098 		rrm_exit(&zfsvfs->z_teardown_lock, FTAG);
2099 	}
2100 
2101 	/*
2102 	 * z_os will be NULL if there was an error in attempting to reopen
2103 	 * zfsvfs, so just return as the properties had already been
2104 	 * unregistered and cached data had been evicted before.
2105 	 */
2106 	if (zfsvfs->z_os == NULL)
2107 		return (0);
2108 
2109 	/*
2110 	 * Unregister properties.
2111 	 */
2112 	zfs_unregister_callbacks(zfsvfs);
2113 
2114 	/*
2115 	 * Evict cached data
2116 	 */
2117 	if (dsl_dataset_is_dirty(dmu_objset_ds(zfsvfs->z_os)) &&
2118 	    !(zfsvfs->z_vfs->vfs_flag & VFS_RDONLY))
2119 		txg_wait_synced(dmu_objset_pool(zfsvfs->z_os), 0);
2120 	dmu_objset_evict_dbufs(zfsvfs->z_os);
2121 
2122 	return (0);
2123 }
2124 
2125 /*ARGSUSED*/
2126 static int
2127 zfs_umount(vfs_t *vfsp, int fflag, cred_t *cr)
2128 {
2129 	zfsvfs_t *zfsvfs = vfsp->vfs_data;
2130 	objset_t *os;
2131 	int ret;
2132 
2133 	ret = secpolicy_fs_unmount(cr, vfsp);
2134 	if (ret) {
2135 		if (dsl_deleg_access((char *)refstr_value(vfsp->vfs_resource),
2136 		    ZFS_DELEG_PERM_MOUNT, cr))
2137 			return (ret);
2138 	}
2139 
2140 	/*
2141 	 * We purge the parent filesystem's vfsp as the parent filesystem
2142 	 * and all of its snapshots have their vnode's v_vfsp set to the
2143 	 * parent's filesystem's vfsp.  Note, 'z_parent' is self
2144 	 * referential for non-snapshots.
2145 	 */
2146 	(void) dnlc_purge_vfsp(zfsvfs->z_parent->z_vfs, 0);
2147 
2148 	/*
2149 	 * Unmount any snapshots mounted under .zfs before unmounting the
2150 	 * dataset itself.
2151 	 */
2152 	if (zfsvfs->z_ctldir != NULL &&
2153 	    (ret = zfsctl_umount_snapshots(vfsp, fflag, cr)) != 0) {
2154 		return (ret);
2155 	}
2156 
2157 	if (!(fflag & MS_FORCE)) {
2158 		/*
2159 		 * Check the number of active vnodes in the file system.
2160 		 * Our count is maintained in the vfs structure, but the
2161 		 * number is off by 1 to indicate a hold on the vfs
2162 		 * structure itself.
2163 		 *
2164 		 * The '.zfs' directory maintains a reference of its
2165 		 * own, and any active references underneath are
2166 		 * reflected in the vnode count.
2167 		 */
2168 		if (zfsvfs->z_ctldir == NULL) {
2169 			if (vfsp->vfs_count > 1)
2170 				return (SET_ERROR(EBUSY));
2171 		} else {
2172 			if (vfsp->vfs_count > 2 ||
2173 			    zfsvfs->z_ctldir->v_count > 1)
2174 				return (SET_ERROR(EBUSY));
2175 		}
2176 	}
2177 
2178 	vfsp->vfs_flag |= VFS_UNMOUNTED;
2179 
2180 	VERIFY(zfsvfs_teardown(zfsvfs, B_TRUE) == 0);
2181 	os = zfsvfs->z_os;
2182 
2183 	/*
2184 	 * z_os will be NULL if there was an error in
2185 	 * attempting to reopen zfsvfs.
2186 	 */
2187 	if (os != NULL) {
2188 		/*
2189 		 * Unset the objset user_ptr.
2190 		 */
2191 		mutex_enter(&os->os_user_ptr_lock);
2192 		dmu_objset_set_user(os, NULL);
2193 		mutex_exit(&os->os_user_ptr_lock);
2194 
2195 		/*
2196 		 * Finally release the objset
2197 		 */
2198 		dmu_objset_disown(os, B_TRUE, zfsvfs);
2199 	}
2200 
2201 	/*
2202 	 * We can now safely destroy the '.zfs' directory node.
2203 	 */
2204 	if (zfsvfs->z_ctldir != NULL)
2205 		zfsctl_destroy(zfsvfs);
2206 
2207 	return (0);
2208 }
2209 
2210 static int
2211 zfs_vget(vfs_t *vfsp, vnode_t **vpp, fid_t *fidp)
2212 {
2213 	zfsvfs_t	*zfsvfs = vfsp->vfs_data;
2214 	znode_t		*zp;
2215 	uint64_t	object = 0;
2216 	uint64_t	fid_gen = 0;
2217 	uint64_t	gen_mask;
2218 	uint64_t	zp_gen;
2219 	int 		i, err;
2220 
2221 	*vpp = NULL;
2222 
2223 	ZFS_ENTER(zfsvfs);
2224 
2225 	if (fidp->fid_len == LONG_FID_LEN) {
2226 		zfid_long_t	*zlfid = (zfid_long_t *)fidp;
2227 		uint64_t	objsetid = 0;
2228 		uint64_t	setgen = 0;
2229 
2230 		for (i = 0; i < sizeof (zlfid->zf_setid); i++)
2231 			objsetid |= ((uint64_t)zlfid->zf_setid[i]) << (8 * i);
2232 
2233 		for (i = 0; i < sizeof (zlfid->zf_setgen); i++)
2234 			setgen |= ((uint64_t)zlfid->zf_setgen[i]) << (8 * i);
2235 
2236 		ZFS_EXIT(zfsvfs);
2237 
2238 		err = zfsctl_lookup_objset(vfsp, objsetid, &zfsvfs);
2239 		if (err)
2240 			return (SET_ERROR(EINVAL));
2241 		ZFS_ENTER(zfsvfs);
2242 	}
2243 
2244 	if (fidp->fid_len == SHORT_FID_LEN || fidp->fid_len == LONG_FID_LEN) {
2245 		zfid_short_t	*zfid = (zfid_short_t *)fidp;
2246 
2247 		for (i = 0; i < sizeof (zfid->zf_object); i++)
2248 			object |= ((uint64_t)zfid->zf_object[i]) << (8 * i);
2249 
2250 		for (i = 0; i < sizeof (zfid->zf_gen); i++)
2251 			fid_gen |= ((uint64_t)zfid->zf_gen[i]) << (8 * i);
2252 	} else {
2253 		ZFS_EXIT(zfsvfs);
2254 		return (SET_ERROR(EINVAL));
2255 	}
2256 
2257 	/* A zero fid_gen means we are in the .zfs control directories */
2258 	if (fid_gen == 0 &&
2259 	    (object == ZFSCTL_INO_ROOT || object == ZFSCTL_INO_SNAPDIR)) {
2260 		*vpp = zfsvfs->z_ctldir;
2261 		ASSERT(*vpp != NULL);
2262 		if (object == ZFSCTL_INO_SNAPDIR) {
2263 			VERIFY(zfsctl_root_lookup(*vpp, "snapshot", vpp, NULL,
2264 			    0, NULL, NULL, NULL, NULL, NULL) == 0);
2265 		} else {
2266 			VN_HOLD(*vpp);
2267 		}
2268 		ZFS_EXIT(zfsvfs);
2269 		return (0);
2270 	}
2271 
2272 	gen_mask = -1ULL >> (64 - 8 * i);
2273 
2274 	dprintf("getting %llu [%u mask %llx]\n", object, fid_gen, gen_mask);
2275 	if (err = zfs_zget(zfsvfs, object, &zp)) {
2276 		ZFS_EXIT(zfsvfs);
2277 		return (err);
2278 	}
2279 	(void) sa_lookup(zp->z_sa_hdl, SA_ZPL_GEN(zfsvfs), &zp_gen,
2280 	    sizeof (uint64_t));
2281 	zp_gen = zp_gen & gen_mask;
2282 	if (zp_gen == 0)
2283 		zp_gen = 1;
2284 	if (zp->z_unlinked || zp_gen != fid_gen) {
2285 		dprintf("znode gen (%u) != fid gen (%u)\n", zp_gen, fid_gen);
2286 		VN_RELE(ZTOV(zp));
2287 		ZFS_EXIT(zfsvfs);
2288 		return (SET_ERROR(EINVAL));
2289 	}
2290 
2291 	*vpp = ZTOV(zp);
2292 	ZFS_EXIT(zfsvfs);
2293 	return (0);
2294 }
2295 
2296 /*
2297  * Block out VOPs and close zfsvfs_t::z_os
2298  *
2299  * Note, if successful, then we return with the 'z_teardown_lock' and
2300  * 'z_teardown_inactive_lock' write held.  We leave ownership of the underlying
2301  * dataset and objset intact so that they can be atomically handed off during
2302  * a subsequent rollback or recv operation and the resume thereafter.
2303  */
2304 int
2305 zfs_suspend_fs(zfsvfs_t *zfsvfs)
2306 {
2307 	int error;
2308 
2309 	if ((error = zfsvfs_teardown(zfsvfs, B_FALSE)) != 0)
2310 		return (error);
2311 
2312 	return (0);
2313 }
2314 
2315 /*
2316  * Rebuild SA and release VOPs.  Note that ownership of the underlying dataset
2317  * is an invariant across any of the operations that can be performed while the
2318  * filesystem was suspended.  Whether it succeeded or failed, the preconditions
2319  * are the same: the relevant objset and associated dataset are owned by
2320  * zfsvfs, held, and long held on entry.
2321  */
2322 int
2323 zfs_resume_fs(zfsvfs_t *zfsvfs, dsl_dataset_t *ds)
2324 {
2325 	int err;
2326 	znode_t *zp;
2327 
2328 	ASSERT(RRM_WRITE_HELD(&zfsvfs->z_teardown_lock));
2329 	ASSERT(RW_WRITE_HELD(&zfsvfs->z_teardown_inactive_lock));
2330 
2331 	/*
2332 	 * We already own this, so just update the objset_t, as the one we
2333 	 * had before may have been evicted.
2334 	 */
2335 	objset_t *os;
2336 	VERIFY3P(ds->ds_owner, ==, zfsvfs);
2337 	VERIFY(dsl_dataset_long_held(ds));
2338 	VERIFY0(dmu_objset_from_ds(ds, &os));
2339 
2340 	err = zfsvfs_init(zfsvfs, os);
2341 	if (err != 0)
2342 		goto bail;
2343 
2344 	VERIFY(zfsvfs_setup(zfsvfs, B_FALSE) == 0);
2345 
2346 	zfs_set_fuid_feature(zfsvfs);
2347 
2348 	/*
2349 	 * Attempt to re-establish all the active znodes with
2350 	 * their dbufs.  If a zfs_rezget() fails, then we'll let
2351 	 * any potential callers discover that via ZFS_ENTER_VERIFY_VP
2352 	 * when they try to use their znode.
2353 	 */
2354 	mutex_enter(&zfsvfs->z_znodes_lock);
2355 	for (zp = list_head(&zfsvfs->z_all_znodes); zp;
2356 	    zp = list_next(&zfsvfs->z_all_znodes, zp)) {
2357 		(void) zfs_rezget(zp);
2358 	}
2359 	mutex_exit(&zfsvfs->z_znodes_lock);
2360 
2361 bail:
2362 	/* release the VOPs */
2363 	rw_exit(&zfsvfs->z_teardown_inactive_lock);
2364 	rrm_exit(&zfsvfs->z_teardown_lock, FTAG);
2365 
2366 	if (err) {
2367 		/*
2368 		 * Since we couldn't setup the sa framework, try to force
2369 		 * unmount this file system.
2370 		 */
2371 		if (vn_vfswlock(zfsvfs->z_vfs->vfs_vnodecovered) == 0)
2372 			(void) dounmount(zfsvfs->z_vfs, MS_FORCE, CRED());
2373 	}
2374 	return (err);
2375 }
2376 
2377 static void
2378 zfs_freevfs(vfs_t *vfsp)
2379 {
2380 	zfsvfs_t *zfsvfs = vfsp->vfs_data;
2381 
2382 	/*
2383 	 * If this is a snapshot, we have an extra VFS_HOLD on our parent
2384 	 * from zfs_mount().  Release it here.  If we came through
2385 	 * zfs_mountroot() instead, we didn't grab an extra hold, so
2386 	 * skip the VFS_RELE for rootvfs.
2387 	 */
2388 	if (zfsvfs->z_issnap && (vfsp != rootvfs))
2389 		VFS_RELE(zfsvfs->z_parent->z_vfs);
2390 
2391 	zfsvfs_free(zfsvfs);
2392 
2393 	atomic_dec_32(&zfs_active_fs_count);
2394 }
2395 
2396 /*
2397  * VFS_INIT() initialization.  Note that there is no VFS_FINI(),
2398  * so we can't safely do any non-idempotent initialization here.
2399  * Leave that to zfs_init() and zfs_fini(), which are called
2400  * from the module's _init() and _fini() entry points.
2401  */
2402 /*ARGSUSED*/
2403 static int
2404 zfs_vfsinit(int fstype, char *name)
2405 {
2406 	int error;
2407 
2408 	zfsfstype = fstype;
2409 
2410 	/*
2411 	 * Setup vfsops and vnodeops tables.
2412 	 */
2413 	error = vfs_setfsops(fstype, zfs_vfsops_template, &zfs_vfsops);
2414 	if (error != 0) {
2415 		cmn_err(CE_WARN, "zfs: bad vfs ops template");
2416 	}
2417 
2418 	error = zfs_create_op_tables();
2419 	if (error) {
2420 		zfs_remove_op_tables();
2421 		cmn_err(CE_WARN, "zfs: bad vnode ops template");
2422 		(void) vfs_freevfsops_by_type(zfsfstype);
2423 		return (error);
2424 	}
2425 
2426 	mutex_init(&zfs_dev_mtx, NULL, MUTEX_DEFAULT, NULL);
2427 
2428 	/*
2429 	 * Unique major number for all zfs mounts.
2430 	 * If we run out of 32-bit minors, we'll getudev() another major.
2431 	 */
2432 	zfs_major = ddi_name_to_major(ZFS_DRIVER);
2433 	zfs_minor = ZFS_MIN_MINOR;
2434 
2435 	return (0);
2436 }
2437 
2438 void
2439 zfs_init(void)
2440 {
2441 	/*
2442 	 * Initialize .zfs directory structures
2443 	 */
2444 	zfsctl_init();
2445 
2446 	/*
2447 	 * Initialize znode cache, vnode ops, etc...
2448 	 */
2449 	zfs_znode_init();
2450 
2451 	dmu_objset_register_type(DMU_OST_ZFS, zfs_space_delta_cb);
2452 }
2453 
2454 void
2455 zfs_fini(void)
2456 {
2457 	zfsctl_fini();
2458 	zfs_znode_fini();
2459 }
2460 
2461 int
2462 zfs_busy(void)
2463 {
2464 	return (zfs_active_fs_count != 0);
2465 }
2466 
2467 int
2468 zfs_set_version(zfsvfs_t *zfsvfs, uint64_t newvers)
2469 {
2470 	int error;
2471 	objset_t *os = zfsvfs->z_os;
2472 	dmu_tx_t *tx;
2473 
2474 	if (newvers < ZPL_VERSION_INITIAL || newvers > ZPL_VERSION)
2475 		return (SET_ERROR(EINVAL));
2476 
2477 	if (newvers < zfsvfs->z_version)
2478 		return (SET_ERROR(EINVAL));
2479 
2480 	if (zfs_spa_version_map(newvers) >
2481 	    spa_version(dmu_objset_spa(zfsvfs->z_os)))
2482 		return (SET_ERROR(ENOTSUP));
2483 
2484 	tx = dmu_tx_create(os);
2485 	dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, B_FALSE, ZPL_VERSION_STR);
2486 	if (newvers >= ZPL_VERSION_SA && !zfsvfs->z_use_sa) {
2487 		dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, B_TRUE,
2488 		    ZFS_SA_ATTRS);
2489 		dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL);
2490 	}
2491 	error = dmu_tx_assign(tx, TXG_WAIT);
2492 	if (error) {
2493 		dmu_tx_abort(tx);
2494 		return (error);
2495 	}
2496 
2497 	error = zap_update(os, MASTER_NODE_OBJ, ZPL_VERSION_STR,
2498 	    8, 1, &newvers, tx);
2499 
2500 	if (error) {
2501 		dmu_tx_commit(tx);
2502 		return (error);
2503 	}
2504 
2505 	if (newvers >= ZPL_VERSION_SA && !zfsvfs->z_use_sa) {
2506 		uint64_t sa_obj;
2507 
2508 		ASSERT3U(spa_version(dmu_objset_spa(zfsvfs->z_os)), >=,
2509 		    SPA_VERSION_SA);
2510 		sa_obj = zap_create(os, DMU_OT_SA_MASTER_NODE,
2511 		    DMU_OT_NONE, 0, tx);
2512 
2513 		error = zap_add(os, MASTER_NODE_OBJ,
2514 		    ZFS_SA_ATTRS, 8, 1, &sa_obj, tx);
2515 		ASSERT0(error);
2516 
2517 		VERIFY(0 == sa_set_sa_object(os, sa_obj));
2518 		sa_register_update_callback(os, zfs_sa_upgrade);
2519 	}
2520 
2521 	spa_history_log_internal_ds(dmu_objset_ds(os), "upgrade", tx,
2522 	    "from %llu to %llu", zfsvfs->z_version, newvers);
2523 
2524 	dmu_tx_commit(tx);
2525 
2526 	zfsvfs->z_version = newvers;
2527 	os->os_version = newvers;
2528 
2529 	zfs_set_fuid_feature(zfsvfs);
2530 
2531 	return (0);
2532 }
2533 
2534 /*
2535  * Read a property stored within the master node.
2536  */
2537 int
2538 zfs_get_zplprop(objset_t *os, zfs_prop_t prop, uint64_t *value)
2539 {
2540 	uint64_t *cached_copy = NULL;
2541 
2542 	/*
2543 	 * Figure out where in the objset_t the cached copy would live, if it
2544 	 * is available for the requested property.
2545 	 */
2546 	if (os != NULL) {
2547 		switch (prop) {
2548 		case ZFS_PROP_VERSION:
2549 			cached_copy = &os->os_version;
2550 			break;
2551 		case ZFS_PROP_NORMALIZE:
2552 			cached_copy = &os->os_normalization;
2553 			break;
2554 		case ZFS_PROP_UTF8ONLY:
2555 			cached_copy = &os->os_utf8only;
2556 			break;
2557 		case ZFS_PROP_CASE:
2558 			cached_copy = &os->os_casesensitivity;
2559 			break;
2560 		default:
2561 			break;
2562 		}
2563 	}
2564 	if (cached_copy != NULL && *cached_copy != OBJSET_PROP_UNINITIALIZED) {
2565 		*value = *cached_copy;
2566 		return (0);
2567 	}
2568 
2569 	/*
2570 	 * If the property wasn't cached, look up the file system's value for
2571 	 * the property. For the version property, we look up a slightly
2572 	 * different string.
2573 	 */
2574 	const char *pname;
2575 	int error = ENOENT;
2576 	if (prop == ZFS_PROP_VERSION) {
2577 		pname = ZPL_VERSION_STR;
2578 	} else {
2579 		pname = zfs_prop_to_name(prop);
2580 	}
2581 
2582 	if (os != NULL) {
2583 		ASSERT3U(os->os_phys->os_type, ==, DMU_OST_ZFS);
2584 		error = zap_lookup(os, MASTER_NODE_OBJ, pname, 8, 1, value);
2585 	}
2586 
2587 	if (error == ENOENT) {
2588 		/* No value set, use the default value */
2589 		switch (prop) {
2590 		case ZFS_PROP_VERSION:
2591 			*value = ZPL_VERSION;
2592 			break;
2593 		case ZFS_PROP_NORMALIZE:
2594 		case ZFS_PROP_UTF8ONLY:
2595 			*value = 0;
2596 			break;
2597 		case ZFS_PROP_CASE:
2598 			*value = ZFS_CASE_SENSITIVE;
2599 			break;
2600 		default:
2601 			return (error);
2602 		}
2603 		error = 0;
2604 	}
2605 
2606 	/*
2607 	 * If one of the methods for getting the property value above worked,
2608 	 * copy it into the objset_t's cache.
2609 	 */
2610 	if (error == 0 && cached_copy != NULL) {
2611 		*cached_copy = *value;
2612 	}
2613 
2614 	return (error);
2615 }
2616 
2617 /*
2618  * Return true if the coresponding vfs's unmounted flag is set.
2619  * Otherwise return false.
2620  * If this function returns true we know VFS unmount has been initiated.
2621  */
2622 boolean_t
2623 zfs_get_vfs_flag_unmounted(objset_t *os)
2624 {
2625 	zfsvfs_t *zfvp;
2626 	boolean_t unmounted = B_FALSE;
2627 
2628 	ASSERT(dmu_objset_type(os) == DMU_OST_ZFS);
2629 
2630 	mutex_enter(&os->os_user_ptr_lock);
2631 	zfvp = dmu_objset_get_user(os);
2632 	if (zfvp != NULL && zfvp->z_vfs != NULL &&
2633 	    (zfvp->z_vfs->vfs_flag & VFS_UNMOUNTED))
2634 		unmounted = B_TRUE;
2635 	mutex_exit(&os->os_user_ptr_lock);
2636 
2637 	return (unmounted);
2638 }
2639 
2640 static vfsdef_t vfw = {
2641 	VFSDEF_VERSION,
2642 	MNTTYPE_ZFS,
2643 	zfs_vfsinit,
2644 	VSW_HASPROTO|VSW_CANRWRO|VSW_CANREMOUNT|VSW_VOLATILEDEV|VSW_STATS|
2645 	    VSW_XID|VSW_ZMOUNT,
2646 	&zfs_mntopts
2647 };
2648 
2649 struct modlfs zfs_modlfs = {
2650 	&mod_fsops, "ZFS filesystem version " SPA_VERSION_STRING, &vfw
2651 };
2652