xref: /titanic_41/usr/src/uts/common/fs/zfs/zfs_vnops.c (revision 5763ba1e357fad1d57b5875c499307b7ea6e2cd4)
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 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /* Portions Copyright 2007 Jeremy Teo */
27 
28 #pragma ident	"%Z%%M%	%I%	%E% SMI"
29 
30 #include <sys/types.h>
31 #include <sys/param.h>
32 #include <sys/time.h>
33 #include <sys/systm.h>
34 #include <sys/sysmacros.h>
35 #include <sys/resource.h>
36 #include <sys/vfs.h>
37 #include <sys/vfs_opreg.h>
38 #include <sys/vnode.h>
39 #include <sys/file.h>
40 #include <sys/stat.h>
41 #include <sys/kmem.h>
42 #include <sys/taskq.h>
43 #include <sys/uio.h>
44 #include <sys/vmsystm.h>
45 #include <sys/atomic.h>
46 #include <sys/vm.h>
47 #include <vm/seg_vn.h>
48 #include <vm/pvn.h>
49 #include <vm/as.h>
50 #include <sys/mman.h>
51 #include <sys/pathname.h>
52 #include <sys/cmn_err.h>
53 #include <sys/errno.h>
54 #include <sys/unistd.h>
55 #include <sys/zfs_vfsops.h>
56 #include <sys/zfs_dir.h>
57 #include <sys/zfs_acl.h>
58 #include <sys/zfs_ioctl.h>
59 #include <sys/zfs_i18n.h>
60 #include <sys/fs/zfs.h>
61 #include <sys/dmu.h>
62 #include <sys/spa.h>
63 #include <sys/txg.h>
64 #include <sys/dbuf.h>
65 #include <sys/zap.h>
66 #include <sys/dirent.h>
67 #include <sys/policy.h>
68 #include <sys/sunddi.h>
69 #include <sys/filio.h>
70 #include "fs/fs_subr.h"
71 #include <sys/zfs_ctldir.h>
72 #include <sys/zfs_fuid.h>
73 #include <sys/dnlc.h>
74 #include <sys/zfs_rlock.h>
75 #include <sys/extdirent.h>
76 #include <sys/kidmap.h>
77 #include <sys/cred_impl.h>
78 
79 /*
80  * Programming rules.
81  *
82  * Each vnode op performs some logical unit of work.  To do this, the ZPL must
83  * properly lock its in-core state, create a DMU transaction, do the work,
84  * record this work in the intent log (ZIL), commit the DMU transaction,
85  * and wait for the intent log to commit if it is a synchronous operation.
86  * Moreover, the vnode ops must work in both normal and log replay context.
87  * The ordering of events is important to avoid deadlocks and references
88  * to freed memory.  The example below illustrates the following Big Rules:
89  *
90  *  (1) A check must be made in each zfs thread for a mounted file system.
91  *	This is done avoiding races using ZFS_ENTER(zfsvfs) or
92  *      ZFS_ENTER_VERIFY(zfsvfs, zp).  A ZFS_EXIT(zfsvfs) is needed before
93  *      all returns.
94  *
95  *  (2)	VN_RELE() should always be the last thing except for zil_commit()
96  *	(if necessary) and ZFS_EXIT(). This is for 3 reasons:
97  *	First, if it's the last reference, the vnode/znode
98  *	can be freed, so the zp may point to freed memory.  Second, the last
99  *	reference will call zfs_zinactive(), which may induce a lot of work --
100  *	pushing cached pages (which acquires range locks) and syncing out
101  *	cached atime changes.  Third, zfs_zinactive() may require a new tx,
102  *	which could deadlock the system if you were already holding one.
103  *
104  *  (3)	All range locks must be grabbed before calling dmu_tx_assign(),
105  *	as they can span dmu_tx_assign() calls.
106  *
107  *  (4)	Always pass zfsvfs->z_assign as the second argument to dmu_tx_assign().
108  *	In normal operation, this will be TXG_NOWAIT.  During ZIL replay,
109  *	it will be a specific txg.  Either way, dmu_tx_assign() never blocks.
110  *	This is critical because we don't want to block while holding locks.
111  *	Note, in particular, that if a lock is sometimes acquired before
112  *	the tx assigns, and sometimes after (e.g. z_lock), then failing to
113  *	use a non-blocking assign can deadlock the system.  The scenario:
114  *
115  *	Thread A has grabbed a lock before calling dmu_tx_assign().
116  *	Thread B is in an already-assigned tx, and blocks for this lock.
117  *	Thread A calls dmu_tx_assign(TXG_WAIT) and blocks in txg_wait_open()
118  *	forever, because the previous txg can't quiesce until B's tx commits.
119  *
120  *	If dmu_tx_assign() returns ERESTART and zfsvfs->z_assign is TXG_NOWAIT,
121  *	then drop all locks, call dmu_tx_wait(), and try again.
122  *
123  *  (5)	If the operation succeeded, generate the intent log entry for it
124  *	before dropping locks.  This ensures that the ordering of events
125  *	in the intent log matches the order in which they actually occurred.
126  *
127  *  (6)	At the end of each vnode op, the DMU tx must always commit,
128  *	regardless of whether there were any errors.
129  *
130  *  (7)	After dropping all locks, invoke zil_commit(zilog, seq, foid)
131  *	to ensure that synchronous semantics are provided when necessary.
132  *
133  * In general, this is how things should be ordered in each vnode op:
134  *
135  *	ZFS_ENTER(zfsvfs);		// exit if unmounted
136  * top:
137  *	zfs_dirent_lock(&dl, ...)	// lock directory entry (may VN_HOLD())
138  *	rw_enter(...);			// grab any other locks you need
139  *	tx = dmu_tx_create(...);	// get DMU tx
140  *	dmu_tx_hold_*();		// hold each object you might modify
141  *	error = dmu_tx_assign(tx, zfsvfs->z_assign);	// try to assign
142  *	if (error) {
143  *		rw_exit(...);		// drop locks
144  *		zfs_dirent_unlock(dl);	// unlock directory entry
145  *		VN_RELE(...);		// release held vnodes
146  *		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
147  *			dmu_tx_wait(tx);
148  *			dmu_tx_abort(tx);
149  *			goto top;
150  *		}
151  *		dmu_tx_abort(tx);	// abort DMU tx
152  *		ZFS_EXIT(zfsvfs);	// finished in zfs
153  *		return (error);		// really out of space
154  *	}
155  *	error = do_real_work();		// do whatever this VOP does
156  *	if (error == 0)
157  *		zfs_log_*(...);		// on success, make ZIL entry
158  *	dmu_tx_commit(tx);		// commit DMU tx -- error or not
159  *	rw_exit(...);			// drop locks
160  *	zfs_dirent_unlock(dl);		// unlock directory entry
161  *	VN_RELE(...);			// release held vnodes
162  *	zil_commit(zilog, seq, foid);	// synchronous when necessary
163  *	ZFS_EXIT(zfsvfs);		// finished in zfs
164  *	return (error);			// done, report error
165  */
166 /* ARGSUSED */
167 static int
168 zfs_open(vnode_t **vpp, int flag, cred_t *cr, caller_context_t *ct)
169 {
170 	znode_t	*zp = VTOZ(*vpp);
171 
172 	if ((flag & FWRITE) && (zp->z_phys->zp_flags & ZFS_APPENDONLY) &&
173 	    ((flag & FAPPEND) == 0)) {
174 		return (EPERM);
175 	}
176 
177 	if (!zfs_has_ctldir(zp) && zp->z_zfsvfs->z_vscan &&
178 	    ZTOV(zp)->v_type == VREG &&
179 	    !(zp->z_phys->zp_flags & ZFS_AV_QUARANTINED) &&
180 	    zp->z_phys->zp_size > 0)
181 		if (fs_vscan(*vpp, cr, 0) != 0)
182 			return (EACCES);
183 
184 	/* Keep a count of the synchronous opens in the znode */
185 	if (flag & (FSYNC | FDSYNC))
186 		atomic_inc_32(&zp->z_sync_cnt);
187 
188 	return (0);
189 }
190 
191 /* ARGSUSED */
192 static int
193 zfs_close(vnode_t *vp, int flag, int count, offset_t offset, cred_t *cr,
194     caller_context_t *ct)
195 {
196 	znode_t	*zp = VTOZ(vp);
197 
198 	/* Decrement the synchronous opens in the znode */
199 	if ((flag & (FSYNC | FDSYNC)) && (count == 1))
200 		atomic_dec_32(&zp->z_sync_cnt);
201 
202 	/*
203 	 * Clean up any locks held by this process on the vp.
204 	 */
205 	cleanlocks(vp, ddi_get_pid(), 0);
206 	cleanshares(vp, ddi_get_pid());
207 
208 	if (!zfs_has_ctldir(zp) && zp->z_zfsvfs->z_vscan &&
209 	    ZTOV(zp)->v_type == VREG &&
210 	    !(zp->z_phys->zp_flags & ZFS_AV_QUARANTINED) &&
211 	    zp->z_phys->zp_size > 0)
212 		VERIFY(fs_vscan(vp, cr, 1) == 0);
213 
214 	return (0);
215 }
216 
217 /*
218  * Lseek support for finding holes (cmd == _FIO_SEEK_HOLE) and
219  * data (cmd == _FIO_SEEK_DATA). "off" is an in/out parameter.
220  */
221 static int
222 zfs_holey(vnode_t *vp, int cmd, offset_t *off)
223 {
224 	znode_t	*zp = VTOZ(vp);
225 	uint64_t noff = (uint64_t)*off; /* new offset */
226 	uint64_t file_sz;
227 	int error;
228 	boolean_t hole;
229 
230 	file_sz = zp->z_phys->zp_size;
231 	if (noff >= file_sz)  {
232 		return (ENXIO);
233 	}
234 
235 	if (cmd == _FIO_SEEK_HOLE)
236 		hole = B_TRUE;
237 	else
238 		hole = B_FALSE;
239 
240 	error = dmu_offset_next(zp->z_zfsvfs->z_os, zp->z_id, hole, &noff);
241 
242 	/* end of file? */
243 	if ((error == ESRCH) || (noff > file_sz)) {
244 		/*
245 		 * Handle the virtual hole at the end of file.
246 		 */
247 		if (hole) {
248 			*off = file_sz;
249 			return (0);
250 		}
251 		return (ENXIO);
252 	}
253 
254 	if (noff < *off)
255 		return (error);
256 	*off = noff;
257 	return (error);
258 }
259 
260 /* ARGSUSED */
261 static int
262 zfs_ioctl(vnode_t *vp, int com, intptr_t data, int flag, cred_t *cred,
263     int *rvalp, caller_context_t *ct)
264 {
265 	offset_t off;
266 	int error;
267 	zfsvfs_t *zfsvfs;
268 	znode_t *zp;
269 
270 	switch (com) {
271 	case _FIOFFS:
272 		return (zfs_sync(vp->v_vfsp, 0, cred));
273 
274 		/*
275 		 * The following two ioctls are used by bfu.  Faking out,
276 		 * necessary to avoid bfu errors.
277 		 */
278 	case _FIOGDIO:
279 	case _FIOSDIO:
280 		return (0);
281 
282 	case _FIO_SEEK_DATA:
283 	case _FIO_SEEK_HOLE:
284 		if (ddi_copyin((void *)data, &off, sizeof (off), flag))
285 			return (EFAULT);
286 
287 		zp = VTOZ(vp);
288 		zfsvfs = zp->z_zfsvfs;
289 		ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
290 
291 		/* offset parameter is in/out */
292 		error = zfs_holey(vp, com, &off);
293 		ZFS_EXIT(zfsvfs);
294 		if (error)
295 			return (error);
296 		if (ddi_copyout(&off, (void *)data, sizeof (off), flag))
297 			return (EFAULT);
298 		return (0);
299 	}
300 	return (ENOTTY);
301 }
302 
303 /*
304  * When a file is memory mapped, we must keep the IO data synchronized
305  * between the DMU cache and the memory mapped pages.  What this means:
306  *
307  * On Write:	If we find a memory mapped page, we write to *both*
308  *		the page and the dmu buffer.
309  *
310  * NOTE: We will always "break up" the IO into PAGESIZE uiomoves when
311  *	the file is memory mapped.
312  */
313 static int
314 mappedwrite(vnode_t *vp, int nbytes, uio_t *uio, dmu_tx_t *tx)
315 {
316 	znode_t	*zp = VTOZ(vp);
317 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
318 	int64_t	start, off;
319 	int len = nbytes;
320 	int error = 0;
321 
322 	start = uio->uio_loffset;
323 	off = start & PAGEOFFSET;
324 	for (start &= PAGEMASK; len > 0; start += PAGESIZE) {
325 		page_t *pp;
326 		uint64_t bytes = MIN(PAGESIZE - off, len);
327 		uint64_t woff = uio->uio_loffset;
328 
329 		/*
330 		 * We don't want a new page to "appear" in the middle of
331 		 * the file update (because it may not get the write
332 		 * update data), so we grab a lock to block
333 		 * zfs_getpage().
334 		 */
335 		rw_enter(&zp->z_map_lock, RW_WRITER);
336 		if (pp = page_lookup(vp, start, SE_SHARED)) {
337 			caddr_t va;
338 
339 			rw_exit(&zp->z_map_lock);
340 			va = ppmapin(pp, PROT_READ | PROT_WRITE, (caddr_t)-1L);
341 			error = uiomove(va+off, bytes, UIO_WRITE, uio);
342 			if (error == 0) {
343 				dmu_write(zfsvfs->z_os, zp->z_id,
344 				    woff, bytes, va+off, tx);
345 			}
346 			ppmapout(va);
347 			page_unlock(pp);
348 		} else {
349 			error = dmu_write_uio(zfsvfs->z_os, zp->z_id,
350 			    uio, bytes, tx);
351 			rw_exit(&zp->z_map_lock);
352 		}
353 		len -= bytes;
354 		off = 0;
355 		if (error)
356 			break;
357 	}
358 	return (error);
359 }
360 
361 /*
362  * When a file is memory mapped, we must keep the IO data synchronized
363  * between the DMU cache and the memory mapped pages.  What this means:
364  *
365  * On Read:	We "read" preferentially from memory mapped pages,
366  *		else we default from the dmu buffer.
367  *
368  * NOTE: We will always "break up" the IO into PAGESIZE uiomoves when
369  *	the file is memory mapped.
370  */
371 static int
372 mappedread(vnode_t *vp, int nbytes, uio_t *uio)
373 {
374 	znode_t *zp = VTOZ(vp);
375 	objset_t *os = zp->z_zfsvfs->z_os;
376 	int64_t	start, off;
377 	int len = nbytes;
378 	int error = 0;
379 
380 	start = uio->uio_loffset;
381 	off = start & PAGEOFFSET;
382 	for (start &= PAGEMASK; len > 0; start += PAGESIZE) {
383 		page_t *pp;
384 		uint64_t bytes = MIN(PAGESIZE - off, len);
385 
386 		if (pp = page_lookup(vp, start, SE_SHARED)) {
387 			caddr_t va;
388 
389 			va = ppmapin(pp, PROT_READ, (caddr_t)-1L);
390 			error = uiomove(va + off, bytes, UIO_READ, uio);
391 			ppmapout(va);
392 			page_unlock(pp);
393 		} else {
394 			error = dmu_read_uio(os, zp->z_id, uio, bytes);
395 		}
396 		len -= bytes;
397 		off = 0;
398 		if (error)
399 			break;
400 	}
401 	return (error);
402 }
403 
404 offset_t zfs_read_chunk_size = 1024 * 1024; /* Tunable */
405 
406 /*
407  * Read bytes from specified file into supplied buffer.
408  *
409  *	IN:	vp	- vnode of file to be read from.
410  *		uio	- structure supplying read location, range info,
411  *			  and return buffer.
412  *		ioflag	- SYNC flags; used to provide FRSYNC semantics.
413  *		cr	- credentials of caller.
414  *		ct	- caller context
415  *
416  *	OUT:	uio	- updated offset and range, buffer filled.
417  *
418  *	RETURN:	0 if success
419  *		error code if failure
420  *
421  * Side Effects:
422  *	vp - atime updated if byte count > 0
423  */
424 /* ARGSUSED */
425 static int
426 zfs_read(vnode_t *vp, uio_t *uio, int ioflag, cred_t *cr, caller_context_t *ct)
427 {
428 	znode_t		*zp = VTOZ(vp);
429 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
430 	objset_t	*os;
431 	ssize_t		n, nbytes;
432 	int		error;
433 	rl_t		*rl;
434 
435 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
436 	os = zfsvfs->z_os;
437 
438 	/*
439 	 * Validate file offset
440 	 */
441 	if (uio->uio_loffset < (offset_t)0) {
442 		ZFS_EXIT(zfsvfs);
443 		return (EINVAL);
444 	}
445 
446 	/*
447 	 * Fasttrack empty reads
448 	 */
449 	if (uio->uio_resid == 0) {
450 		ZFS_EXIT(zfsvfs);
451 		return (0);
452 	}
453 
454 	/*
455 	 * Check for mandatory locks
456 	 */
457 	if (MANDMODE((mode_t)zp->z_phys->zp_mode)) {
458 		if (error = chklock(vp, FREAD,
459 		    uio->uio_loffset, uio->uio_resid, uio->uio_fmode, ct)) {
460 			ZFS_EXIT(zfsvfs);
461 			return (error);
462 		}
463 	}
464 
465 	/*
466 	 * If we're in FRSYNC mode, sync out this znode before reading it.
467 	 */
468 	if (ioflag & FRSYNC)
469 		zil_commit(zfsvfs->z_log, zp->z_last_itx, zp->z_id);
470 
471 	/*
472 	 * Lock the range against changes.
473 	 */
474 	rl = zfs_range_lock(zp, uio->uio_loffset, uio->uio_resid, RL_READER);
475 
476 	/*
477 	 * If we are reading past end-of-file we can skip
478 	 * to the end; but we might still need to set atime.
479 	 */
480 	if (uio->uio_loffset >= zp->z_phys->zp_size) {
481 		error = 0;
482 		goto out;
483 	}
484 
485 	ASSERT(uio->uio_loffset < zp->z_phys->zp_size);
486 	n = MIN(uio->uio_resid, zp->z_phys->zp_size - uio->uio_loffset);
487 
488 	while (n > 0) {
489 		nbytes = MIN(n, zfs_read_chunk_size -
490 		    P2PHASE(uio->uio_loffset, zfs_read_chunk_size));
491 
492 		if (vn_has_cached_data(vp))
493 			error = mappedread(vp, nbytes, uio);
494 		else
495 			error = dmu_read_uio(os, zp->z_id, uio, nbytes);
496 		if (error)
497 			break;
498 
499 		n -= nbytes;
500 	}
501 
502 out:
503 	zfs_range_unlock(rl);
504 
505 	ZFS_ACCESSTIME_STAMP(zfsvfs, zp);
506 	ZFS_EXIT(zfsvfs);
507 	return (error);
508 }
509 
510 /*
511  * Fault in the pages of the first n bytes specified by the uio structure.
512  * 1 byte in each page is touched and the uio struct is unmodified.
513  * Any error will exit this routine as this is only a best
514  * attempt to get the pages resident. This is a copy of ufs_trans_touch().
515  */
516 static void
517 zfs_prefault_write(ssize_t n, struct uio *uio)
518 {
519 	struct iovec *iov;
520 	ulong_t cnt, incr;
521 	caddr_t p;
522 	uint8_t tmp;
523 
524 	iov = uio->uio_iov;
525 
526 	while (n) {
527 		cnt = MIN(iov->iov_len, n);
528 		if (cnt == 0) {
529 			/* empty iov entry */
530 			iov++;
531 			continue;
532 		}
533 		n -= cnt;
534 		/*
535 		 * touch each page in this segment.
536 		 */
537 		p = iov->iov_base;
538 		while (cnt) {
539 			switch (uio->uio_segflg) {
540 			case UIO_USERSPACE:
541 			case UIO_USERISPACE:
542 				if (fuword8(p, &tmp))
543 					return;
544 				break;
545 			case UIO_SYSSPACE:
546 				if (kcopy(p, &tmp, 1))
547 					return;
548 				break;
549 			}
550 			incr = MIN(cnt, PAGESIZE);
551 			p += incr;
552 			cnt -= incr;
553 		}
554 		/*
555 		 * touch the last byte in case it straddles a page.
556 		 */
557 		p--;
558 		switch (uio->uio_segflg) {
559 		case UIO_USERSPACE:
560 		case UIO_USERISPACE:
561 			if (fuword8(p, &tmp))
562 				return;
563 			break;
564 		case UIO_SYSSPACE:
565 			if (kcopy(p, &tmp, 1))
566 				return;
567 			break;
568 		}
569 		iov++;
570 	}
571 }
572 
573 /*
574  * Write the bytes to a file.
575  *
576  *	IN:	vp	- vnode of file to be written to.
577  *		uio	- structure supplying write location, range info,
578  *			  and data buffer.
579  *		ioflag	- FAPPEND flag set if in append mode.
580  *		cr	- credentials of caller.
581  *		ct	- caller context (NFS/CIFS fem monitor only)
582  *
583  *	OUT:	uio	- updated offset and range.
584  *
585  *	RETURN:	0 if success
586  *		error code if failure
587  *
588  * Timestamps:
589  *	vp - ctime|mtime updated if byte count > 0
590  */
591 /* ARGSUSED */
592 static int
593 zfs_write(vnode_t *vp, uio_t *uio, int ioflag, cred_t *cr, caller_context_t *ct)
594 {
595 	znode_t		*zp = VTOZ(vp);
596 	rlim64_t	limit = uio->uio_llimit;
597 	ssize_t		start_resid = uio->uio_resid;
598 	ssize_t		tx_bytes;
599 	uint64_t	end_size;
600 	dmu_tx_t	*tx;
601 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
602 	zilog_t		*zilog;
603 	offset_t	woff;
604 	ssize_t		n, nbytes;
605 	rl_t		*rl;
606 	int		max_blksz = zfsvfs->z_max_blksz;
607 	uint64_t	pflags = zp->z_phys->zp_flags;
608 	int		error;
609 
610 	/*
611 	 * If immutable or not appending then return EPERM
612 	 */
613 	if ((pflags & (ZFS_IMMUTABLE | ZFS_READONLY)) ||
614 	    ((pflags & ZFS_APPENDONLY) && !(ioflag & FAPPEND) &&
615 	    (uio->uio_loffset < zp->z_phys->zp_size)))
616 		return (EPERM);
617 
618 	/*
619 	 * Fasttrack empty write
620 	 */
621 	n = start_resid;
622 	if (n == 0)
623 		return (0);
624 
625 	if (limit == RLIM64_INFINITY || limit > MAXOFFSET_T)
626 		limit = MAXOFFSET_T;
627 
628 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
629 	zilog = zfsvfs->z_log;
630 
631 	/*
632 	 * Pre-fault the pages to ensure slow (eg NFS) pages
633 	 * don't hold up txg.
634 	 */
635 	zfs_prefault_write(n, uio);
636 
637 	/*
638 	 * If in append mode, set the io offset pointer to eof.
639 	 */
640 	if (ioflag & FAPPEND) {
641 		/*
642 		 * Range lock for a file append:
643 		 * The value for the start of range will be determined by
644 		 * zfs_range_lock() (to guarantee append semantics).
645 		 * If this write will cause the block size to increase,
646 		 * zfs_range_lock() will lock the entire file, so we must
647 		 * later reduce the range after we grow the block size.
648 		 */
649 		rl = zfs_range_lock(zp, 0, n, RL_APPEND);
650 		if (rl->r_len == UINT64_MAX) {
651 			/* overlocked, zp_size can't change */
652 			woff = uio->uio_loffset = zp->z_phys->zp_size;
653 		} else {
654 			woff = uio->uio_loffset = rl->r_off;
655 		}
656 	} else {
657 		woff = uio->uio_loffset;
658 		/*
659 		 * Validate file offset
660 		 */
661 		if (woff < 0) {
662 			ZFS_EXIT(zfsvfs);
663 			return (EINVAL);
664 		}
665 
666 		/*
667 		 * If we need to grow the block size then zfs_range_lock()
668 		 * will lock a wider range than we request here.
669 		 * Later after growing the block size we reduce the range.
670 		 */
671 		rl = zfs_range_lock(zp, woff, n, RL_WRITER);
672 	}
673 
674 	if (woff >= limit) {
675 		zfs_range_unlock(rl);
676 		ZFS_EXIT(zfsvfs);
677 		return (EFBIG);
678 	}
679 
680 	if ((woff + n) > limit || woff > (limit - n))
681 		n = limit - woff;
682 
683 	/*
684 	 * Check for mandatory locks
685 	 */
686 	if (MANDMODE((mode_t)zp->z_phys->zp_mode) &&
687 	    (error = chklock(vp, FWRITE, woff, n, uio->uio_fmode, ct)) != 0) {
688 		zfs_range_unlock(rl);
689 		ZFS_EXIT(zfsvfs);
690 		return (error);
691 	}
692 	end_size = MAX(zp->z_phys->zp_size, woff + n);
693 
694 	/*
695 	 * Write the file in reasonable size chunks.  Each chunk is written
696 	 * in a separate transaction; this keeps the intent log records small
697 	 * and allows us to do more fine-grained space accounting.
698 	 */
699 	while (n > 0) {
700 		/*
701 		 * Start a transaction.
702 		 */
703 		woff = uio->uio_loffset;
704 		tx = dmu_tx_create(zfsvfs->z_os);
705 		dmu_tx_hold_bonus(tx, zp->z_id);
706 		dmu_tx_hold_write(tx, zp->z_id, woff, MIN(n, max_blksz));
707 		error = dmu_tx_assign(tx, zfsvfs->z_assign);
708 		if (error) {
709 			if (error == ERESTART &&
710 			    zfsvfs->z_assign == TXG_NOWAIT) {
711 				dmu_tx_wait(tx);
712 				dmu_tx_abort(tx);
713 				continue;
714 			}
715 			dmu_tx_abort(tx);
716 			break;
717 		}
718 
719 		/*
720 		 * If zfs_range_lock() over-locked we grow the blocksize
721 		 * and then reduce the lock range.  This will only happen
722 		 * on the first iteration since zfs_range_reduce() will
723 		 * shrink down r_len to the appropriate size.
724 		 */
725 		if (rl->r_len == UINT64_MAX) {
726 			uint64_t new_blksz;
727 
728 			if (zp->z_blksz > max_blksz) {
729 				ASSERT(!ISP2(zp->z_blksz));
730 				new_blksz = MIN(end_size, SPA_MAXBLOCKSIZE);
731 			} else {
732 				new_blksz = MIN(end_size, max_blksz);
733 			}
734 			zfs_grow_blocksize(zp, new_blksz, tx);
735 			zfs_range_reduce(rl, woff, n);
736 		}
737 
738 		/*
739 		 * XXX - should we really limit each write to z_max_blksz?
740 		 * Perhaps we should use SPA_MAXBLOCKSIZE chunks?
741 		 */
742 		nbytes = MIN(n, max_blksz - P2PHASE(woff, max_blksz));
743 		rw_enter(&zp->z_map_lock, RW_READER);
744 
745 		tx_bytes = uio->uio_resid;
746 		if (vn_has_cached_data(vp)) {
747 			rw_exit(&zp->z_map_lock);
748 			error = mappedwrite(vp, nbytes, uio, tx);
749 		} else {
750 			error = dmu_write_uio(zfsvfs->z_os, zp->z_id,
751 			    uio, nbytes, tx);
752 			rw_exit(&zp->z_map_lock);
753 		}
754 		tx_bytes -= uio->uio_resid;
755 
756 		/*
757 		 * If we made no progress, we're done.  If we made even
758 		 * partial progress, update the znode and ZIL accordingly.
759 		 */
760 		if (tx_bytes == 0) {
761 			dmu_tx_commit(tx);
762 			ASSERT(error != 0);
763 			break;
764 		}
765 
766 		/*
767 		 * Clear Set-UID/Set-GID bits on successful write if not
768 		 * privileged and at least one of the excute bits is set.
769 		 *
770 		 * It would be nice to to this after all writes have
771 		 * been done, but that would still expose the ISUID/ISGID
772 		 * to another app after the partial write is committed.
773 		 *
774 		 * Note: we don't call zfs_fuid_map_id() here because
775 		 * user 0 is not an ephemeral uid.
776 		 */
777 		mutex_enter(&zp->z_acl_lock);
778 		if ((zp->z_phys->zp_mode & (S_IXUSR | (S_IXUSR >> 3) |
779 		    (S_IXUSR >> 6))) != 0 &&
780 		    (zp->z_phys->zp_mode & (S_ISUID | S_ISGID)) != 0 &&
781 		    secpolicy_vnode_setid_retain(cr,
782 		    (zp->z_phys->zp_mode & S_ISUID) != 0 &&
783 		    zp->z_phys->zp_uid == 0) != 0) {
784 			zp->z_phys->zp_mode &= ~(S_ISUID | S_ISGID);
785 		}
786 		mutex_exit(&zp->z_acl_lock);
787 
788 		/*
789 		 * Update time stamp.  NOTE: This marks the bonus buffer as
790 		 * dirty, so we don't have to do it again for zp_size.
791 		 */
792 		zfs_time_stamper(zp, CONTENT_MODIFIED, tx);
793 
794 		/*
795 		 * Update the file size (zp_size) if it has changed;
796 		 * account for possible concurrent updates.
797 		 */
798 		while ((end_size = zp->z_phys->zp_size) < uio->uio_loffset)
799 			(void) atomic_cas_64(&zp->z_phys->zp_size, end_size,
800 			    uio->uio_loffset);
801 		zfs_log_write(zilog, tx, TX_WRITE, zp, woff, tx_bytes, ioflag);
802 		dmu_tx_commit(tx);
803 
804 		if (error != 0)
805 			break;
806 		ASSERT(tx_bytes == nbytes);
807 		n -= nbytes;
808 	}
809 
810 	zfs_range_unlock(rl);
811 
812 	/*
813 	 * If we're in replay mode, or we made no progress, return error.
814 	 * Otherwise, it's at least a partial write, so it's successful.
815 	 */
816 	if (zfsvfs->z_assign >= TXG_INITIAL || uio->uio_resid == start_resid) {
817 		ZFS_EXIT(zfsvfs);
818 		return (error);
819 	}
820 
821 	if (ioflag & (FSYNC | FDSYNC))
822 		zil_commit(zilog, zp->z_last_itx, zp->z_id);
823 
824 	ZFS_EXIT(zfsvfs);
825 	return (0);
826 }
827 
828 void
829 zfs_get_done(dmu_buf_t *db, void *vzgd)
830 {
831 	zgd_t *zgd = (zgd_t *)vzgd;
832 	rl_t *rl = zgd->zgd_rl;
833 	vnode_t *vp = ZTOV(rl->r_zp);
834 
835 	dmu_buf_rele(db, vzgd);
836 	zfs_range_unlock(rl);
837 	VN_RELE(vp);
838 	zil_add_vdev(zgd->zgd_zilog, DVA_GET_VDEV(BP_IDENTITY(zgd->zgd_bp)));
839 	kmem_free(zgd, sizeof (zgd_t));
840 }
841 
842 /*
843  * Get data to generate a TX_WRITE intent log record.
844  */
845 int
846 zfs_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio)
847 {
848 	zfsvfs_t *zfsvfs = arg;
849 	objset_t *os = zfsvfs->z_os;
850 	znode_t *zp;
851 	uint64_t off = lr->lr_offset;
852 	dmu_buf_t *db;
853 	rl_t *rl;
854 	zgd_t *zgd;
855 	int dlen = lr->lr_length;		/* length of user data */
856 	int error = 0;
857 
858 	ASSERT(zio);
859 	ASSERT(dlen != 0);
860 
861 	/*
862 	 * Nothing to do if the file has been removed
863 	 */
864 	if (zfs_zget(zfsvfs, lr->lr_foid, &zp) != 0)
865 		return (ENOENT);
866 	if (zp->z_unlinked) {
867 		VN_RELE(ZTOV(zp));
868 		return (ENOENT);
869 	}
870 
871 	/*
872 	 * Write records come in two flavors: immediate and indirect.
873 	 * For small writes it's cheaper to store the data with the
874 	 * log record (immediate); for large writes it's cheaper to
875 	 * sync the data and get a pointer to it (indirect) so that
876 	 * we don't have to write the data twice.
877 	 */
878 	if (buf != NULL) { /* immediate write */
879 		rl = zfs_range_lock(zp, off, dlen, RL_READER);
880 		/* test for truncation needs to be done while range locked */
881 		if (off >= zp->z_phys->zp_size) {
882 			error = ENOENT;
883 			goto out;
884 		}
885 		VERIFY(0 == dmu_read(os, lr->lr_foid, off, dlen, buf));
886 	} else { /* indirect write */
887 		uint64_t boff; /* block starting offset */
888 
889 		/*
890 		 * Have to lock the whole block to ensure when it's
891 		 * written out and it's checksum is being calculated
892 		 * that no one can change the data. We need to re-check
893 		 * blocksize after we get the lock in case it's changed!
894 		 */
895 		for (;;) {
896 			if (ISP2(zp->z_blksz)) {
897 				boff = P2ALIGN_TYPED(off, zp->z_blksz,
898 				    uint64_t);
899 			} else {
900 				boff = 0;
901 			}
902 			dlen = zp->z_blksz;
903 			rl = zfs_range_lock(zp, boff, dlen, RL_READER);
904 			if (zp->z_blksz == dlen)
905 				break;
906 			zfs_range_unlock(rl);
907 		}
908 		/* test for truncation needs to be done while range locked */
909 		if (off >= zp->z_phys->zp_size) {
910 			error = ENOENT;
911 			goto out;
912 		}
913 		zgd = (zgd_t *)kmem_alloc(sizeof (zgd_t), KM_SLEEP);
914 		zgd->zgd_rl = rl;
915 		zgd->zgd_zilog = zfsvfs->z_log;
916 		zgd->zgd_bp = &lr->lr_blkptr;
917 		VERIFY(0 == dmu_buf_hold(os, lr->lr_foid, boff, zgd, &db));
918 		ASSERT(boff == db->db_offset);
919 		lr->lr_blkoff = off - boff;
920 		error = dmu_sync(zio, db, &lr->lr_blkptr,
921 		    lr->lr_common.lrc_txg, zfs_get_done, zgd);
922 		ASSERT((error && error != EINPROGRESS) ||
923 		    lr->lr_length <= zp->z_blksz);
924 		if (error == 0) {
925 			zil_add_vdev(zfsvfs->z_log,
926 			    DVA_GET_VDEV(BP_IDENTITY(&lr->lr_blkptr)));
927 		}
928 		/*
929 		 * If we get EINPROGRESS, then we need to wait for a
930 		 * write IO initiated by dmu_sync() to complete before
931 		 * we can release this dbuf.  We will finish everything
932 		 * up in the zfs_get_done() callback.
933 		 */
934 		if (error == EINPROGRESS)
935 			return (0);
936 		dmu_buf_rele(db, zgd);
937 		kmem_free(zgd, sizeof (zgd_t));
938 	}
939 out:
940 	zfs_range_unlock(rl);
941 	VN_RELE(ZTOV(zp));
942 	return (error);
943 }
944 
945 /*ARGSUSED*/
946 static int
947 zfs_access(vnode_t *vp, int mode, int flag, cred_t *cr,
948     caller_context_t *ct)
949 {
950 	znode_t *zp = VTOZ(vp);
951 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
952 	int error;
953 
954 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
955 
956 	if (flag & V_ACE_MASK)
957 		error = zfs_zaccess(zp, mode, flag, B_FALSE, cr);
958 	else
959 		error = zfs_zaccess_rwx(zp, mode, flag, cr);
960 
961 	ZFS_EXIT(zfsvfs);
962 	return (error);
963 }
964 
965 /*
966  * Lookup an entry in a directory, or an extended attribute directory.
967  * If it exists, return a held vnode reference for it.
968  *
969  *	IN:	dvp	- vnode of directory to search.
970  *		nm	- name of entry to lookup.
971  *		pnp	- full pathname to lookup [UNUSED].
972  *		flags	- LOOKUP_XATTR set if looking for an attribute.
973  *		rdir	- root directory vnode [UNUSED].
974  *		cr	- credentials of caller.
975  *		ct	- caller context
976  *		direntflags - directory lookup flags
977  *		realpnp - returned pathname.
978  *
979  *	OUT:	vpp	- vnode of located entry, NULL if not found.
980  *
981  *	RETURN:	0 if success
982  *		error code if failure
983  *
984  * Timestamps:
985  *	NA
986  */
987 /* ARGSUSED */
988 static int
989 zfs_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, struct pathname *pnp,
990     int flags, vnode_t *rdir, cred_t *cr,  caller_context_t *ct,
991     int *direntflags, pathname_t *realpnp)
992 {
993 	znode_t *zdp = VTOZ(dvp);
994 	zfsvfs_t *zfsvfs = zdp->z_zfsvfs;
995 	int	error;
996 
997 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zdp);
998 
999 	*vpp = NULL;
1000 
1001 	if (flags & LOOKUP_XATTR) {
1002 		/*
1003 		 * If the xattr property is off, refuse the lookup request.
1004 		 */
1005 		if (!(zfsvfs->z_vfs->vfs_flag & VFS_XATTR)) {
1006 			ZFS_EXIT(zfsvfs);
1007 			return (EINVAL);
1008 		}
1009 
1010 		/*
1011 		 * We don't allow recursive attributes..
1012 		 * Maybe someday we will.
1013 		 */
1014 		if (zdp->z_phys->zp_flags & ZFS_XATTR) {
1015 			ZFS_EXIT(zfsvfs);
1016 			return (EINVAL);
1017 		}
1018 
1019 		if (error = zfs_get_xattrdir(VTOZ(dvp), vpp, cr, flags)) {
1020 			ZFS_EXIT(zfsvfs);
1021 			return (error);
1022 		}
1023 
1024 		/*
1025 		 * Do we have permission to get into attribute directory?
1026 		 */
1027 
1028 		if (error = zfs_zaccess(VTOZ(*vpp), ACE_EXECUTE, 0,
1029 		    B_FALSE, cr)) {
1030 			VN_RELE(*vpp);
1031 			*vpp = NULL;
1032 		}
1033 
1034 		ZFS_EXIT(zfsvfs);
1035 		return (error);
1036 	}
1037 
1038 	if (dvp->v_type != VDIR) {
1039 		ZFS_EXIT(zfsvfs);
1040 		return (ENOTDIR);
1041 	}
1042 
1043 	/*
1044 	 * Check accessibility of directory.
1045 	 */
1046 
1047 	if (error = zfs_zaccess(zdp, ACE_EXECUTE, 0, B_FALSE, cr)) {
1048 		ZFS_EXIT(zfsvfs);
1049 		return (error);
1050 	}
1051 
1052 	if (zfsvfs->z_case & ZFS_UTF8_ONLY && u8_validate(nm, strlen(nm),
1053 	    NULL, U8_VALIDATE_ENTIRE, &error) < 0) {
1054 		ZFS_EXIT(zfsvfs);
1055 		return (EILSEQ);
1056 	}
1057 
1058 	error = zfs_dirlook(zdp, nm, vpp, flags, direntflags, realpnp);
1059 	if (error == 0) {
1060 		/*
1061 		 * Convert device special files
1062 		 */
1063 		if (IS_DEVVP(*vpp)) {
1064 			vnode_t	*svp;
1065 
1066 			svp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type, cr);
1067 			VN_RELE(*vpp);
1068 			if (svp == NULL)
1069 				error = ENOSYS;
1070 			else
1071 				*vpp = svp;
1072 		}
1073 	}
1074 
1075 	ZFS_EXIT(zfsvfs);
1076 	return (error);
1077 }
1078 
1079 /*
1080  * Attempt to create a new entry in a directory.  If the entry
1081  * already exists, truncate the file if permissible, else return
1082  * an error.  Return the vp of the created or trunc'd file.
1083  *
1084  *	IN:	dvp	- vnode of directory to put new file entry in.
1085  *		name	- name of new file entry.
1086  *		vap	- attributes of new file.
1087  *		excl	- flag indicating exclusive or non-exclusive mode.
1088  *		mode	- mode to open file with.
1089  *		cr	- credentials of caller.
1090  *		flag	- large file flag [UNUSED].
1091  *		ct	- caller context
1092  *		vsecp 	- ACL to be set
1093  *
1094  *	OUT:	vpp	- vnode of created or trunc'd entry.
1095  *
1096  *	RETURN:	0 if success
1097  *		error code if failure
1098  *
1099  * Timestamps:
1100  *	dvp - ctime|mtime updated if new entry created
1101  *	 vp - ctime|mtime always, atime if new
1102  */
1103 
1104 /* ARGSUSED */
1105 static int
1106 zfs_create(vnode_t *dvp, char *name, vattr_t *vap, vcexcl_t excl,
1107     int mode, vnode_t **vpp, cred_t *cr, int flag, caller_context_t *ct,
1108     vsecattr_t *vsecp)
1109 {
1110 	znode_t		*zp, *dzp = VTOZ(dvp);
1111 	zfsvfs_t	*zfsvfs = dzp->z_zfsvfs;
1112 	zilog_t		*zilog;
1113 	objset_t	*os;
1114 	zfs_dirlock_t	*dl;
1115 	dmu_tx_t	*tx;
1116 	int		error;
1117 	uint64_t	zoid;
1118 	zfs_acl_t	*aclp = NULL;
1119 	zfs_fuid_info_t *fuidp = NULL;
1120 
1121 	/*
1122 	 * If we have an ephemeral id, ACL, or XVATTR then
1123 	 * make sure file system is at proper version
1124 	 */
1125 
1126 	if (zfsvfs->z_use_fuids == B_FALSE &&
1127 	    (vsecp || (vap->va_mask & AT_XVATTR) ||
1128 	    IS_EPHEMERAL(crgetuid(cr)) || IS_EPHEMERAL(crgetgid(cr))))
1129 		return (EINVAL);
1130 
1131 	ZFS_ENTER_VERIFY_ZP(zfsvfs, dzp);
1132 	os = zfsvfs->z_os;
1133 	zilog = zfsvfs->z_log;
1134 
1135 	if (zfsvfs->z_case & ZFS_UTF8_ONLY && u8_validate(name, strlen(name),
1136 	    NULL, U8_VALIDATE_ENTIRE, &error) < 0) {
1137 		ZFS_EXIT(zfsvfs);
1138 		return (EILSEQ);
1139 	}
1140 
1141 	if (vap->va_mask & AT_XVATTR) {
1142 		if ((error = secpolicy_xvattr((xvattr_t *)vap,
1143 		    crgetuid(cr), cr, vap->va_type)) != 0) {
1144 			ZFS_EXIT(zfsvfs);
1145 			return (error);
1146 		}
1147 	}
1148 top:
1149 	*vpp = NULL;
1150 
1151 	if ((vap->va_mode & VSVTX) && secpolicy_vnode_stky_modify(cr))
1152 		vap->va_mode &= ~VSVTX;
1153 
1154 	if (*name == '\0') {
1155 		/*
1156 		 * Null component name refers to the directory itself.
1157 		 */
1158 		VN_HOLD(dvp);
1159 		zp = dzp;
1160 		dl = NULL;
1161 		error = 0;
1162 	} else {
1163 		/* possible VN_HOLD(zp) */
1164 		int zflg = 0;
1165 
1166 		if (flag & FIGNORECASE)
1167 			zflg |= ZCILOOK;
1168 
1169 		error = zfs_dirent_lock(&dl, dzp, name, &zp, zflg,
1170 		    NULL, NULL);
1171 		if (error) {
1172 			if (strcmp(name, "..") == 0)
1173 				error = EISDIR;
1174 			ZFS_EXIT(zfsvfs);
1175 			if (aclp)
1176 				zfs_acl_free(aclp);
1177 			return (error);
1178 		}
1179 	}
1180 	if (vsecp && aclp == NULL) {
1181 		error = zfs_vsec_2_aclp(zfsvfs, vap->va_type, vsecp, &aclp);
1182 		if (error) {
1183 			ZFS_EXIT(zfsvfs);
1184 			if (dl)
1185 				zfs_dirent_unlock(dl);
1186 			return (error);
1187 		}
1188 	}
1189 	zoid = zp ? zp->z_id : -1ULL;
1190 
1191 	if (zp == NULL) {
1192 		uint64_t txtype;
1193 
1194 		/*
1195 		 * Create a new file object and update the directory
1196 		 * to reference it.
1197 		 */
1198 		if (error = zfs_zaccess(dzp, ACE_ADD_FILE, 0, B_FALSE, cr)) {
1199 			goto out;
1200 		}
1201 
1202 		/*
1203 		 * We only support the creation of regular files in
1204 		 * extended attribute directories.
1205 		 */
1206 		if ((dzp->z_phys->zp_flags & ZFS_XATTR) &&
1207 		    (vap->va_type != VREG)) {
1208 			error = EINVAL;
1209 			goto out;
1210 		}
1211 
1212 		tx = dmu_tx_create(os);
1213 		dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT);
1214 		if (zfsvfs->z_fuid_obj == 0) {
1215 			dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT);
1216 			dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0,
1217 			    SPA_MAXBLOCKSIZE);
1218 			dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, FALSE, NULL);
1219 		} else {
1220 			dmu_tx_hold_bonus(tx, zfsvfs->z_fuid_obj);
1221 			dmu_tx_hold_write(tx, zfsvfs->z_fuid_obj, 0,
1222 			    SPA_MAXBLOCKSIZE);
1223 		}
1224 		dmu_tx_hold_bonus(tx, dzp->z_id);
1225 		dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name);
1226 		if ((dzp->z_phys->zp_flags & ZFS_INHERIT_ACE) || aclp) {
1227 			dmu_tx_hold_write(tx, DMU_NEW_OBJECT,
1228 			    0, SPA_MAXBLOCKSIZE);
1229 		}
1230 		error = dmu_tx_assign(tx, zfsvfs->z_assign);
1231 		if (error) {
1232 			zfs_dirent_unlock(dl);
1233 			if (error == ERESTART &&
1234 			    zfsvfs->z_assign == TXG_NOWAIT) {
1235 				dmu_tx_wait(tx);
1236 				dmu_tx_abort(tx);
1237 				goto top;
1238 			}
1239 			dmu_tx_abort(tx);
1240 			ZFS_EXIT(zfsvfs);
1241 			if (aclp)
1242 				zfs_acl_free(aclp);
1243 			return (error);
1244 		}
1245 		zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0, aclp, &fuidp);
1246 		ASSERT(zp->z_id == zoid);
1247 		(void) zfs_link_create(dl, zp, tx, ZNEW);
1248 		txtype = zfs_log_create_txtype(Z_FILE, vsecp, vap);
1249 		if (flag & FIGNORECASE)
1250 			txtype |= TX_CI;
1251 		zfs_log_create(zilog, tx, txtype, dzp, zp, name,
1252 		    vsecp, fuidp, vap);
1253 		if (fuidp)
1254 			zfs_fuid_info_free(fuidp);
1255 		dmu_tx_commit(tx);
1256 	} else {
1257 		int aflags = (flag & FAPPEND) ? V_APPEND : 0;
1258 
1259 		/*
1260 		 * A directory entry already exists for this name.
1261 		 */
1262 		/*
1263 		 * Can't truncate an existing file if in exclusive mode.
1264 		 */
1265 		if (excl == EXCL) {
1266 			error = EEXIST;
1267 			goto out;
1268 		}
1269 		/*
1270 		 * Can't open a directory for writing.
1271 		 */
1272 		if ((ZTOV(zp)->v_type == VDIR) && (mode & S_IWRITE)) {
1273 			error = EISDIR;
1274 			goto out;
1275 		}
1276 		/*
1277 		 * Verify requested access to file.
1278 		 */
1279 		if (mode && (error = zfs_zaccess_rwx(zp, mode, aflags, cr))) {
1280 			goto out;
1281 		}
1282 
1283 		mutex_enter(&dzp->z_lock);
1284 		dzp->z_seq++;
1285 		mutex_exit(&dzp->z_lock);
1286 
1287 		/*
1288 		 * Truncate regular files if requested.
1289 		 */
1290 		if ((ZTOV(zp)->v_type == VREG) &&
1291 		    (vap->va_mask & AT_SIZE) && (vap->va_size == 0)) {
1292 			error = zfs_freesp(zp, 0, 0, mode, TRUE);
1293 			if (error == ERESTART &&
1294 			    zfsvfs->z_assign == TXG_NOWAIT) {
1295 				/* NB: we already did dmu_tx_wait() */
1296 				zfs_dirent_unlock(dl);
1297 				VN_RELE(ZTOV(zp));
1298 				goto top;
1299 			}
1300 
1301 			if (error == 0) {
1302 				vnevent_create(ZTOV(zp), ct);
1303 			}
1304 		}
1305 	}
1306 out:
1307 
1308 	if (dl)
1309 		zfs_dirent_unlock(dl);
1310 
1311 	if (error) {
1312 		if (zp)
1313 			VN_RELE(ZTOV(zp));
1314 	} else {
1315 		*vpp = ZTOV(zp);
1316 		/*
1317 		 * If vnode is for a device return a specfs vnode instead.
1318 		 */
1319 		if (IS_DEVVP(*vpp)) {
1320 			struct vnode *svp;
1321 
1322 			svp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type, cr);
1323 			VN_RELE(*vpp);
1324 			if (svp == NULL) {
1325 				error = ENOSYS;
1326 			}
1327 			*vpp = svp;
1328 		}
1329 	}
1330 	if (aclp)
1331 		zfs_acl_free(aclp);
1332 
1333 	ZFS_EXIT(zfsvfs);
1334 	return (error);
1335 }
1336 
1337 /*
1338  * Remove an entry from a directory.
1339  *
1340  *	IN:	dvp	- vnode of directory to remove entry from.
1341  *		name	- name of entry to remove.
1342  *		cr	- credentials of caller.
1343  *		ct	- caller context
1344  *		flags	- case flags
1345  *
1346  *	RETURN:	0 if success
1347  *		error code if failure
1348  *
1349  * Timestamps:
1350  *	dvp - ctime|mtime
1351  *	 vp - ctime (if nlink > 0)
1352  */
1353 /*ARGSUSED*/
1354 static int
1355 zfs_remove(vnode_t *dvp, char *name, cred_t *cr, caller_context_t *ct,
1356     int flags)
1357 {
1358 	znode_t		*zp, *dzp = VTOZ(dvp);
1359 	znode_t		*xzp = NULL;
1360 	vnode_t		*vp;
1361 	zfsvfs_t	*zfsvfs = dzp->z_zfsvfs;
1362 	zilog_t		*zilog;
1363 	uint64_t	acl_obj, xattr_obj;
1364 	zfs_dirlock_t	*dl;
1365 	dmu_tx_t	*tx;
1366 	boolean_t	may_delete_now, delete_now = FALSE;
1367 	boolean_t	unlinked;
1368 	uint64_t	txtype;
1369 	pathname_t	*realnmp = NULL;
1370 	pathname_t	realnm;
1371 	int		error;
1372 	int		zflg = ZEXISTS;
1373 
1374 	ZFS_ENTER_VERIFY_ZP(zfsvfs, dzp);
1375 	zilog = zfsvfs->z_log;
1376 
1377 	if (flags & FIGNORECASE) {
1378 		zflg |= ZCILOOK;
1379 		pn_alloc(&realnm);
1380 		realnmp = &realnm;
1381 	}
1382 
1383 top:
1384 	/*
1385 	 * Attempt to lock directory; fail if entry doesn't exist.
1386 	 */
1387 	if (error = zfs_dirent_lock(&dl, dzp, name, &zp, zflg,
1388 	    NULL, realnmp)) {
1389 		if (realnmp)
1390 			pn_free(realnmp);
1391 		ZFS_EXIT(zfsvfs);
1392 		return (error);
1393 	}
1394 
1395 	vp = ZTOV(zp);
1396 
1397 	if (error = zfs_zaccess_delete(dzp, zp, cr)) {
1398 		goto out;
1399 	}
1400 
1401 	/*
1402 	 * Need to use rmdir for removing directories.
1403 	 */
1404 	if (vp->v_type == VDIR) {
1405 		error = EPERM;
1406 		goto out;
1407 	}
1408 
1409 	vnevent_remove(vp, dvp, name, ct);
1410 
1411 	if (realnmp)
1412 		dnlc_remove(dvp, realnmp->pn_path);
1413 	else
1414 		dnlc_remove(dvp, name);
1415 
1416 	mutex_enter(&vp->v_lock);
1417 	may_delete_now = vp->v_count == 1 && !vn_has_cached_data(vp);
1418 	mutex_exit(&vp->v_lock);
1419 
1420 	/*
1421 	 * We may delete the znode now, or we may put it in the unlinked set;
1422 	 * it depends on whether we're the last link, and on whether there are
1423 	 * other holds on the vnode.  So we dmu_tx_hold() the right things to
1424 	 * allow for either case.
1425 	 */
1426 	tx = dmu_tx_create(zfsvfs->z_os);
1427 	dmu_tx_hold_zap(tx, dzp->z_id, FALSE, name);
1428 	dmu_tx_hold_bonus(tx, zp->z_id);
1429 	if (may_delete_now)
1430 		dmu_tx_hold_free(tx, zp->z_id, 0, DMU_OBJECT_END);
1431 
1432 	/* are there any extended attributes? */
1433 	if ((xattr_obj = zp->z_phys->zp_xattr) != 0) {
1434 		/* XXX - do we need this if we are deleting? */
1435 		dmu_tx_hold_bonus(tx, xattr_obj);
1436 	}
1437 
1438 	/* are there any additional acls */
1439 	if ((acl_obj = zp->z_phys->zp_acl.z_acl_extern_obj) != 0 &&
1440 	    may_delete_now)
1441 		dmu_tx_hold_free(tx, acl_obj, 0, DMU_OBJECT_END);
1442 
1443 	/* charge as an update -- would be nice not to charge at all */
1444 	dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
1445 
1446 	error = dmu_tx_assign(tx, zfsvfs->z_assign);
1447 	if (error) {
1448 		zfs_dirent_unlock(dl);
1449 		VN_RELE(vp);
1450 		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
1451 			dmu_tx_wait(tx);
1452 			dmu_tx_abort(tx);
1453 			goto top;
1454 		}
1455 		if (realnmp)
1456 			pn_free(realnmp);
1457 		dmu_tx_abort(tx);
1458 		ZFS_EXIT(zfsvfs);
1459 		return (error);
1460 	}
1461 
1462 	/*
1463 	 * Remove the directory entry.
1464 	 */
1465 	error = zfs_link_destroy(dl, zp, tx, zflg, &unlinked);
1466 
1467 	if (error) {
1468 		dmu_tx_commit(tx);
1469 		goto out;
1470 	}
1471 
1472 	if (unlinked) {
1473 		mutex_enter(&vp->v_lock);
1474 		delete_now = may_delete_now &&
1475 		    vp->v_count == 1 && !vn_has_cached_data(vp) &&
1476 		    zp->z_phys->zp_xattr == xattr_obj &&
1477 		    zp->z_phys->zp_acl.z_acl_extern_obj == acl_obj;
1478 		mutex_exit(&vp->v_lock);
1479 	}
1480 
1481 	if (delete_now) {
1482 		if (zp->z_phys->zp_xattr) {
1483 			error = zfs_zget(zfsvfs, zp->z_phys->zp_xattr, &xzp);
1484 			ASSERT3U(error, ==, 0);
1485 			ASSERT3U(xzp->z_phys->zp_links, ==, 2);
1486 			dmu_buf_will_dirty(xzp->z_dbuf, tx);
1487 			mutex_enter(&xzp->z_lock);
1488 			xzp->z_unlinked = 1;
1489 			xzp->z_phys->zp_links = 0;
1490 			mutex_exit(&xzp->z_lock);
1491 			zfs_unlinked_add(xzp, tx);
1492 			zp->z_phys->zp_xattr = 0; /* probably unnecessary */
1493 		}
1494 		mutex_enter(&zp->z_lock);
1495 		mutex_enter(&vp->v_lock);
1496 		vp->v_count--;
1497 		ASSERT3U(vp->v_count, ==, 0);
1498 		mutex_exit(&vp->v_lock);
1499 		mutex_exit(&zp->z_lock);
1500 		zfs_znode_delete(zp, tx);
1501 		VFS_RELE(zfsvfs->z_vfs);
1502 	} else if (unlinked) {
1503 		zfs_unlinked_add(zp, tx);
1504 	}
1505 
1506 	txtype = TX_REMOVE;
1507 	if (flags & FIGNORECASE)
1508 		txtype |= TX_CI;
1509 	zfs_log_remove(zilog, tx, txtype, dzp, name);
1510 
1511 	dmu_tx_commit(tx);
1512 out:
1513 	if (realnmp)
1514 		pn_free(realnmp);
1515 
1516 	zfs_dirent_unlock(dl);
1517 
1518 	if (!delete_now) {
1519 		VN_RELE(vp);
1520 	} else if (xzp) {
1521 		/* this rele delayed to prevent nesting transactions */
1522 		VN_RELE(ZTOV(xzp));
1523 	}
1524 
1525 	ZFS_EXIT(zfsvfs);
1526 	return (error);
1527 }
1528 
1529 /*
1530  * Create a new directory and insert it into dvp using the name
1531  * provided.  Return a pointer to the inserted directory.
1532  *
1533  *	IN:	dvp	- vnode of directory to add subdir to.
1534  *		dirname	- name of new directory.
1535  *		vap	- attributes of new directory.
1536  *		cr	- credentials of caller.
1537  *		ct	- caller context
1538  *		vsecp	- ACL to be set
1539  *
1540  *	OUT:	vpp	- vnode of created directory.
1541  *
1542  *	RETURN:	0 if success
1543  *		error code if failure
1544  *
1545  * Timestamps:
1546  *	dvp - ctime|mtime updated
1547  *	 vp - ctime|mtime|atime updated
1548  */
1549 /*ARGSUSED*/
1550 static int
1551 zfs_mkdir(vnode_t *dvp, char *dirname, vattr_t *vap, vnode_t **vpp, cred_t *cr,
1552     caller_context_t *ct, int flags, vsecattr_t *vsecp)
1553 {
1554 	znode_t		*zp, *dzp = VTOZ(dvp);
1555 	zfsvfs_t	*zfsvfs = dzp->z_zfsvfs;
1556 	zilog_t		*zilog;
1557 	zfs_dirlock_t	*dl;
1558 	uint64_t	zoid = 0;
1559 	uint64_t	txtype;
1560 	dmu_tx_t	*tx;
1561 	int		error;
1562 	zfs_acl_t	*aclp = NULL;
1563 	zfs_fuid_info_t	*fuidp = NULL;
1564 	int		zf = ZNEW;
1565 
1566 	ASSERT(vap->va_type == VDIR);
1567 
1568 	/*
1569 	 * If we have an ephemeral id, ACL, or XVATTR then
1570 	 * make sure file system is at proper version
1571 	 */
1572 
1573 	if (zfsvfs->z_use_fuids == B_FALSE &&
1574 	    (vsecp || (vap->va_mask & AT_XVATTR) || IS_EPHEMERAL(crgetuid(cr))||
1575 	    IS_EPHEMERAL(crgetgid(cr))))
1576 		return (EINVAL);
1577 
1578 	ZFS_ENTER_VERIFY_ZP(zfsvfs, dzp);
1579 	zilog = zfsvfs->z_log;
1580 
1581 	if (dzp->z_phys->zp_flags & ZFS_XATTR) {
1582 		ZFS_EXIT(zfsvfs);
1583 		return (EINVAL);
1584 	}
1585 
1586 	if (zfsvfs->z_case & ZFS_UTF8_ONLY && u8_validate(dirname,
1587 	    strlen(dirname), NULL, U8_VALIDATE_ENTIRE, &error) < 0) {
1588 		ZFS_EXIT(zfsvfs);
1589 		return (EILSEQ);
1590 	}
1591 	if (flags & FIGNORECASE)
1592 		zf |= ZCILOOK;
1593 
1594 	if (vap->va_mask & AT_XVATTR)
1595 		if ((error = secpolicy_xvattr((xvattr_t *)vap,
1596 		    crgetuid(cr), cr, vap->va_type)) != 0) {
1597 			ZFS_EXIT(zfsvfs);
1598 			return (error);
1599 		}
1600 
1601 	/*
1602 	 * First make sure the new directory doesn't exist.
1603 	 */
1604 top:
1605 	*vpp = NULL;
1606 
1607 	if (error = zfs_dirent_lock(&dl, dzp, dirname, &zp, zf,
1608 	    NULL, NULL)) {
1609 		ZFS_EXIT(zfsvfs);
1610 		return (error);
1611 	}
1612 
1613 	if (error = zfs_zaccess(dzp, ACE_ADD_SUBDIRECTORY, 0, B_FALSE, cr)) {
1614 		zfs_dirent_unlock(dl);
1615 		ZFS_EXIT(zfsvfs);
1616 		return (error);
1617 	}
1618 
1619 	if (vsecp && aclp == NULL) {
1620 		error = zfs_vsec_2_aclp(zfsvfs, vap->va_type, vsecp, &aclp);
1621 		if (error) {
1622 			zfs_dirent_unlock(dl);
1623 			ZFS_EXIT(zfsvfs);
1624 			return (error);
1625 		}
1626 	}
1627 	/*
1628 	 * Add a new entry to the directory.
1629 	 */
1630 	tx = dmu_tx_create(zfsvfs->z_os);
1631 	dmu_tx_hold_zap(tx, dzp->z_id, TRUE, dirname);
1632 	dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL);
1633 	if (zfsvfs->z_fuid_obj == 0) {
1634 		dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT);
1635 		dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0,
1636 		    SPA_MAXBLOCKSIZE);
1637 		dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, FALSE, NULL);
1638 	} else {
1639 		dmu_tx_hold_bonus(tx, zfsvfs->z_fuid_obj);
1640 		dmu_tx_hold_write(tx, zfsvfs->z_fuid_obj, 0,
1641 		    SPA_MAXBLOCKSIZE);
1642 	}
1643 	if ((dzp->z_phys->zp_flags & ZFS_INHERIT_ACE) || aclp)
1644 		dmu_tx_hold_write(tx, DMU_NEW_OBJECT,
1645 		    0, SPA_MAXBLOCKSIZE);
1646 	error = dmu_tx_assign(tx, zfsvfs->z_assign);
1647 	if (error) {
1648 		zfs_dirent_unlock(dl);
1649 		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
1650 			dmu_tx_wait(tx);
1651 			dmu_tx_abort(tx);
1652 			goto top;
1653 		}
1654 		dmu_tx_abort(tx);
1655 		ZFS_EXIT(zfsvfs);
1656 		if (aclp)
1657 			zfs_acl_free(aclp);
1658 		return (error);
1659 	}
1660 
1661 	/*
1662 	 * Create new node.
1663 	 */
1664 	zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0, aclp, &fuidp);
1665 
1666 	if (aclp)
1667 		zfs_acl_free(aclp);
1668 
1669 	/*
1670 	 * Now put new name in parent dir.
1671 	 */
1672 	(void) zfs_link_create(dl, zp, tx, ZNEW);
1673 
1674 	*vpp = ZTOV(zp);
1675 
1676 	txtype = zfs_log_create_txtype(Z_DIR, vsecp, vap);
1677 	if (flags & FIGNORECASE)
1678 		txtype |= TX_CI;
1679 	zfs_log_create(zilog, tx, txtype, dzp, zp, dirname, vsecp, fuidp, vap);
1680 
1681 	if (fuidp)
1682 		zfs_fuid_info_free(fuidp);
1683 	dmu_tx_commit(tx);
1684 
1685 	zfs_dirent_unlock(dl);
1686 
1687 	ZFS_EXIT(zfsvfs);
1688 	return (0);
1689 }
1690 
1691 /*
1692  * Remove a directory subdir entry.  If the current working
1693  * directory is the same as the subdir to be removed, the
1694  * remove will fail.
1695  *
1696  *	IN:	dvp	- vnode of directory to remove from.
1697  *		name	- name of directory to be removed.
1698  *		cwd	- vnode of current working directory.
1699  *		cr	- credentials of caller.
1700  *		ct	- caller context
1701  *		flags	- case flags
1702  *
1703  *	RETURN:	0 if success
1704  *		error code if failure
1705  *
1706  * Timestamps:
1707  *	dvp - ctime|mtime updated
1708  */
1709 /*ARGSUSED*/
1710 static int
1711 zfs_rmdir(vnode_t *dvp, char *name, vnode_t *cwd, cred_t *cr,
1712     caller_context_t *ct, int flags)
1713 {
1714 	znode_t		*dzp = VTOZ(dvp);
1715 	znode_t		*zp;
1716 	vnode_t		*vp;
1717 	zfsvfs_t	*zfsvfs = dzp->z_zfsvfs;
1718 	zilog_t		*zilog;
1719 	zfs_dirlock_t	*dl;
1720 	dmu_tx_t	*tx;
1721 	int		error;
1722 	int		zflg = ZEXISTS;
1723 
1724 	ZFS_ENTER_VERIFY_ZP(zfsvfs, dzp);
1725 	zilog = zfsvfs->z_log;
1726 
1727 	if (flags & FIGNORECASE)
1728 		zflg |= ZCILOOK;
1729 top:
1730 	zp = NULL;
1731 
1732 	/*
1733 	 * Attempt to lock directory; fail if entry doesn't exist.
1734 	 */
1735 	if (error = zfs_dirent_lock(&dl, dzp, name, &zp, zflg,
1736 	    NULL, NULL)) {
1737 		ZFS_EXIT(zfsvfs);
1738 		return (error);
1739 	}
1740 
1741 	vp = ZTOV(zp);
1742 
1743 	if (error = zfs_zaccess_delete(dzp, zp, cr)) {
1744 		goto out;
1745 	}
1746 
1747 	if (vp->v_type != VDIR) {
1748 		error = ENOTDIR;
1749 		goto out;
1750 	}
1751 
1752 	if (vp == cwd) {
1753 		error = EINVAL;
1754 		goto out;
1755 	}
1756 
1757 	vnevent_rmdir(vp, dvp, name, ct);
1758 
1759 	/*
1760 	 * Grab a lock on the directory to make sure that noone is
1761 	 * trying to add (or lookup) entries while we are removing it.
1762 	 */
1763 	rw_enter(&zp->z_name_lock, RW_WRITER);
1764 
1765 	/*
1766 	 * Grab a lock on the parent pointer to make sure we play well
1767 	 * with the treewalk and directory rename code.
1768 	 */
1769 	rw_enter(&zp->z_parent_lock, RW_WRITER);
1770 
1771 	tx = dmu_tx_create(zfsvfs->z_os);
1772 	dmu_tx_hold_zap(tx, dzp->z_id, FALSE, name);
1773 	dmu_tx_hold_bonus(tx, zp->z_id);
1774 	dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
1775 	error = dmu_tx_assign(tx, zfsvfs->z_assign);
1776 	if (error) {
1777 		rw_exit(&zp->z_parent_lock);
1778 		rw_exit(&zp->z_name_lock);
1779 		zfs_dirent_unlock(dl);
1780 		VN_RELE(vp);
1781 		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
1782 			dmu_tx_wait(tx);
1783 			dmu_tx_abort(tx);
1784 			goto top;
1785 		}
1786 		dmu_tx_abort(tx);
1787 		ZFS_EXIT(zfsvfs);
1788 		return (error);
1789 	}
1790 
1791 	error = zfs_link_destroy(dl, zp, tx, zflg, NULL);
1792 
1793 	if (error == 0) {
1794 		uint64_t txtype = TX_RMDIR;
1795 		if (flags & FIGNORECASE)
1796 			txtype |= TX_CI;
1797 		zfs_log_remove(zilog, tx, txtype, dzp, name);
1798 	}
1799 
1800 	dmu_tx_commit(tx);
1801 
1802 	rw_exit(&zp->z_parent_lock);
1803 	rw_exit(&zp->z_name_lock);
1804 out:
1805 	zfs_dirent_unlock(dl);
1806 
1807 	VN_RELE(vp);
1808 
1809 	ZFS_EXIT(zfsvfs);
1810 	return (error);
1811 }
1812 
1813 /*
1814  * Read as many directory entries as will fit into the provided
1815  * buffer from the given directory cursor position (specified in
1816  * the uio structure.
1817  *
1818  *	IN:	vp	- vnode of directory to read.
1819  *		uio	- structure supplying read location, range info,
1820  *			  and return buffer.
1821  *		cr	- credentials of caller.
1822  *		ct	- caller context
1823  *		flags	- case flags
1824  *
1825  *	OUT:	uio	- updated offset and range, buffer filled.
1826  *		eofp	- set to true if end-of-file detected.
1827  *
1828  *	RETURN:	0 if success
1829  *		error code if failure
1830  *
1831  * Timestamps:
1832  *	vp - atime updated
1833  *
1834  * Note that the low 4 bits of the cookie returned by zap is always zero.
1835  * This allows us to use the low range for "special" directory entries:
1836  * We use 0 for '.', and 1 for '..'.  If this is the root of the filesystem,
1837  * we use the offset 2 for the '.zfs' directory.
1838  */
1839 /* ARGSUSED */
1840 static int
1841 zfs_readdir(vnode_t *vp, uio_t *uio, cred_t *cr, int *eofp,
1842     caller_context_t *ct, int flags)
1843 {
1844 	znode_t		*zp = VTOZ(vp);
1845 	iovec_t		*iovp;
1846 	edirent_t	*eodp;
1847 	dirent64_t	*odp;
1848 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
1849 	objset_t	*os;
1850 	caddr_t		outbuf;
1851 	size_t		bufsize;
1852 	zap_cursor_t	zc;
1853 	zap_attribute_t	zap;
1854 	uint_t		bytes_wanted;
1855 	uint64_t	offset; /* must be unsigned; checks for < 1 */
1856 	int		local_eof;
1857 	int		outcount;
1858 	int		error;
1859 	uint8_t		prefetch;
1860 
1861 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
1862 
1863 	/*
1864 	 * If we are not given an eof variable,
1865 	 * use a local one.
1866 	 */
1867 	if (eofp == NULL)
1868 		eofp = &local_eof;
1869 
1870 	/*
1871 	 * Check for valid iov_len.
1872 	 */
1873 	if (uio->uio_iov->iov_len <= 0) {
1874 		ZFS_EXIT(zfsvfs);
1875 		return (EINVAL);
1876 	}
1877 
1878 	/*
1879 	 * Quit if directory has been removed (posix)
1880 	 */
1881 	if ((*eofp = zp->z_unlinked) != 0) {
1882 		ZFS_EXIT(zfsvfs);
1883 		return (0);
1884 	}
1885 
1886 	error = 0;
1887 	os = zfsvfs->z_os;
1888 	offset = uio->uio_loffset;
1889 	prefetch = zp->z_zn_prefetch;
1890 
1891 	/*
1892 	 * Initialize the iterator cursor.
1893 	 */
1894 	if (offset <= 3) {
1895 		/*
1896 		 * Start iteration from the beginning of the directory.
1897 		 */
1898 		zap_cursor_init(&zc, os, zp->z_id);
1899 	} else {
1900 		/*
1901 		 * The offset is a serialized cursor.
1902 		 */
1903 		zap_cursor_init_serialized(&zc, os, zp->z_id, offset);
1904 	}
1905 
1906 	/*
1907 	 * Get space to change directory entries into fs independent format.
1908 	 */
1909 	iovp = uio->uio_iov;
1910 	bytes_wanted = iovp->iov_len;
1911 	if (uio->uio_segflg != UIO_SYSSPACE || uio->uio_iovcnt != 1) {
1912 		bufsize = bytes_wanted;
1913 		outbuf = kmem_alloc(bufsize, KM_SLEEP);
1914 		odp = (struct dirent64 *)outbuf;
1915 	} else {
1916 		bufsize = bytes_wanted;
1917 		odp = (struct dirent64 *)iovp->iov_base;
1918 	}
1919 	eodp = (struct edirent *)odp;
1920 
1921 	/*
1922 	 * Transform to file-system independent format
1923 	 */
1924 	outcount = 0;
1925 	while (outcount < bytes_wanted) {
1926 		ino64_t objnum;
1927 		ushort_t reclen;
1928 		off64_t *next;
1929 
1930 		/*
1931 		 * Special case `.', `..', and `.zfs'.
1932 		 */
1933 		if (offset == 0) {
1934 			(void) strcpy(zap.za_name, ".");
1935 			zap.za_normalization_conflict = 0;
1936 			objnum = zp->z_id;
1937 		} else if (offset == 1) {
1938 			(void) strcpy(zap.za_name, "..");
1939 			zap.za_normalization_conflict = 0;
1940 			objnum = zp->z_phys->zp_parent;
1941 		} else if (offset == 2 && zfs_show_ctldir(zp)) {
1942 			(void) strcpy(zap.za_name, ZFS_CTLDIR_NAME);
1943 			zap.za_normalization_conflict = 0;
1944 			objnum = ZFSCTL_INO_ROOT;
1945 		} else {
1946 			/*
1947 			 * Grab next entry.
1948 			 */
1949 			if (error = zap_cursor_retrieve(&zc, &zap)) {
1950 				if ((*eofp = (error == ENOENT)) != 0)
1951 					break;
1952 				else
1953 					goto update;
1954 			}
1955 
1956 			if (zap.za_integer_length != 8 ||
1957 			    zap.za_num_integers != 1) {
1958 				cmn_err(CE_WARN, "zap_readdir: bad directory "
1959 				    "entry, obj = %lld, offset = %lld\n",
1960 				    (u_longlong_t)zp->z_id,
1961 				    (u_longlong_t)offset);
1962 				error = ENXIO;
1963 				goto update;
1964 			}
1965 
1966 			objnum = ZFS_DIRENT_OBJ(zap.za_first_integer);
1967 			/*
1968 			 * MacOS X can extract the object type here such as:
1969 			 * uint8_t type = ZFS_DIRENT_TYPE(zap.za_first_integer);
1970 			 */
1971 		}
1972 
1973 		if (flags & V_RDDIR_ENTFLAGS)
1974 			reclen = EDIRENT_RECLEN(strlen(zap.za_name));
1975 		else
1976 			reclen = DIRENT64_RECLEN(strlen(zap.za_name));
1977 
1978 		/*
1979 		 * Will this entry fit in the buffer?
1980 		 */
1981 		if (outcount + reclen > bufsize) {
1982 			/*
1983 			 * Did we manage to fit anything in the buffer?
1984 			 */
1985 			if (!outcount) {
1986 				error = EINVAL;
1987 				goto update;
1988 			}
1989 			break;
1990 		}
1991 		if (flags & V_RDDIR_ENTFLAGS) {
1992 			/*
1993 			 * Add extended flag entry:
1994 			 */
1995 			eodp->ed_ino = objnum;
1996 			eodp->ed_reclen = reclen;
1997 			/* NOTE: ed_off is the offset for the *next* entry */
1998 			next = &(eodp->ed_off);
1999 			eodp->ed_eflags = zap.za_normalization_conflict ?
2000 			    ED_CASE_CONFLICT : 0;
2001 			(void) strncpy(eodp->ed_name, zap.za_name,
2002 			    EDIRENT_NAMELEN(reclen));
2003 			eodp = (edirent_t *)((intptr_t)eodp + reclen);
2004 		} else {
2005 			/*
2006 			 * Add normal entry:
2007 			 */
2008 			odp->d_ino = objnum;
2009 			odp->d_reclen = reclen;
2010 			/* NOTE: d_off is the offset for the *next* entry */
2011 			next = &(odp->d_off);
2012 			(void) strncpy(odp->d_name, zap.za_name,
2013 			    DIRENT64_NAMELEN(reclen));
2014 			odp = (dirent64_t *)((intptr_t)odp + reclen);
2015 		}
2016 		outcount += reclen;
2017 
2018 		ASSERT(outcount <= bufsize);
2019 
2020 		/* Prefetch znode */
2021 		if (prefetch)
2022 			dmu_prefetch(os, objnum, 0, 0);
2023 
2024 		/*
2025 		 * Move to the next entry, fill in the previous offset.
2026 		 */
2027 		if (offset > 2 || (offset == 2 && !zfs_show_ctldir(zp))) {
2028 			zap_cursor_advance(&zc);
2029 			offset = zap_cursor_serialize(&zc);
2030 		} else {
2031 			offset += 1;
2032 		}
2033 		*next = offset;
2034 	}
2035 	zp->z_zn_prefetch = B_FALSE; /* a lookup will re-enable pre-fetching */
2036 
2037 	if (uio->uio_segflg == UIO_SYSSPACE && uio->uio_iovcnt == 1) {
2038 		iovp->iov_base += outcount;
2039 		iovp->iov_len -= outcount;
2040 		uio->uio_resid -= outcount;
2041 	} else if (error = uiomove(outbuf, (long)outcount, UIO_READ, uio)) {
2042 		/*
2043 		 * Reset the pointer.
2044 		 */
2045 		offset = uio->uio_loffset;
2046 	}
2047 
2048 update:
2049 	zap_cursor_fini(&zc);
2050 	if (uio->uio_segflg != UIO_SYSSPACE || uio->uio_iovcnt != 1)
2051 		kmem_free(outbuf, bufsize);
2052 
2053 	if (error == ENOENT)
2054 		error = 0;
2055 
2056 	ZFS_ACCESSTIME_STAMP(zfsvfs, zp);
2057 
2058 	uio->uio_loffset = offset;
2059 	ZFS_EXIT(zfsvfs);
2060 	return (error);
2061 }
2062 
2063 ulong_t zfs_fsync_sync_cnt = 4;
2064 
2065 static int
2066 zfs_fsync(vnode_t *vp, int syncflag, cred_t *cr, caller_context_t *ct)
2067 {
2068 	znode_t	*zp = VTOZ(vp);
2069 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
2070 
2071 	/*
2072 	 * Regardless of whether this is required for standards conformance,
2073 	 * this is the logical behavior when fsync() is called on a file with
2074 	 * dirty pages.  We use B_ASYNC since the ZIL transactions are already
2075 	 * going to be pushed out as part of the zil_commit().
2076 	 */
2077 	if (vn_has_cached_data(vp) && !(syncflag & FNODSYNC) &&
2078 	    (vp->v_type == VREG) && !(IS_SWAPVP(vp)))
2079 		(void) VOP_PUTPAGE(vp, (offset_t)0, (size_t)0, B_ASYNC, cr, ct);
2080 
2081 	(void) tsd_set(zfs_fsyncer_key, (void *)zfs_fsync_sync_cnt);
2082 
2083 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
2084 	zil_commit(zfsvfs->z_log, zp->z_last_itx, zp->z_id);
2085 	ZFS_EXIT(zfsvfs);
2086 	return (0);
2087 }
2088 
2089 
2090 /*
2091  * Get the requested file attributes and place them in the provided
2092  * vattr structure.
2093  *
2094  *	IN:	vp	- vnode of file.
2095  *		vap	- va_mask identifies requested attributes.
2096  *			  If AT_XVATTR set, then optional attrs are requested
2097  *		flags	- ATTR_NOACLCHECK (CIFS server context)
2098  *		cr	- credentials of caller.
2099  *		ct	- caller context
2100  *
2101  *	OUT:	vap	- attribute values.
2102  *
2103  *	RETURN:	0 (always succeeds)
2104  */
2105 /* ARGSUSED */
2106 static int
2107 zfs_getattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr,
2108     caller_context_t *ct)
2109 {
2110 	znode_t *zp = VTOZ(vp);
2111 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
2112 	znode_phys_t *pzp;
2113 	int	error = 0;
2114 	uint64_t links;
2115 	xvattr_t *xvap = (xvattr_t *)vap;	/* vap may be an xvattr_t * */
2116 	xoptattr_t *xoap = NULL;
2117 	boolean_t skipaclchk = (flags & ATTR_NOACLCHECK) ? B_TRUE : B_FALSE;
2118 
2119 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
2120 	pzp = zp->z_phys;
2121 
2122 	mutex_enter(&zp->z_lock);
2123 
2124 	/*
2125 	 * If ACL is trivial don't bother looking for ACE_READ_ATTRIBUTES.
2126 	 * Also, if we are the owner don't bother, since owner should
2127 	 * always be allowed to read basic attributes of file.
2128 	 */
2129 	if (!(pzp->zp_flags & ZFS_ACL_TRIVIAL) &&
2130 	    (pzp->zp_uid != crgetuid(cr))) {
2131 		if (error = zfs_zaccess(zp, ACE_READ_ATTRIBUTES, 0,
2132 		    skipaclchk, cr)) {
2133 			mutex_exit(&zp->z_lock);
2134 			ZFS_EXIT(zfsvfs);
2135 			return (error);
2136 		}
2137 	}
2138 
2139 	/*
2140 	 * Return all attributes.  It's cheaper to provide the answer
2141 	 * than to determine whether we were asked the question.
2142 	 */
2143 
2144 	vap->va_type = vp->v_type;
2145 	vap->va_mode = pzp->zp_mode & MODEMASK;
2146 	zfs_fuid_map_ids(zp, &vap->va_uid, &vap->va_gid);
2147 	vap->va_fsid = zp->z_zfsvfs->z_vfs->vfs_dev;
2148 	vap->va_nodeid = zp->z_id;
2149 	if ((vp->v_flag & VROOT) && zfs_show_ctldir(zp))
2150 		links = pzp->zp_links + 1;
2151 	else
2152 		links = pzp->zp_links;
2153 	vap->va_nlink = MIN(links, UINT32_MAX);	/* nlink_t limit! */
2154 	vap->va_size = pzp->zp_size;
2155 	vap->va_rdev = vp->v_rdev;
2156 	vap->va_seq = zp->z_seq;
2157 
2158 	/*
2159 	 * Add in any requested optional attributes and the create time.
2160 	 * Also set the corresponding bits in the returned attribute bitmap.
2161 	 */
2162 	if ((xoap = xva_getxoptattr(xvap)) != NULL && zfsvfs->z_use_fuids) {
2163 		if (XVA_ISSET_REQ(xvap, XAT_ARCHIVE)) {
2164 			xoap->xoa_archive =
2165 			    ((pzp->zp_flags & ZFS_ARCHIVE) != 0);
2166 			XVA_SET_RTN(xvap, XAT_ARCHIVE);
2167 		}
2168 
2169 		if (XVA_ISSET_REQ(xvap, XAT_READONLY)) {
2170 			xoap->xoa_readonly =
2171 			    ((pzp->zp_flags & ZFS_READONLY) != 0);
2172 			XVA_SET_RTN(xvap, XAT_READONLY);
2173 		}
2174 
2175 		if (XVA_ISSET_REQ(xvap, XAT_SYSTEM)) {
2176 			xoap->xoa_system =
2177 			    ((pzp->zp_flags & ZFS_SYSTEM) != 0);
2178 			XVA_SET_RTN(xvap, XAT_SYSTEM);
2179 		}
2180 
2181 		if (XVA_ISSET_REQ(xvap, XAT_HIDDEN)) {
2182 			xoap->xoa_hidden =
2183 			    ((pzp->zp_flags & ZFS_HIDDEN) != 0);
2184 			XVA_SET_RTN(xvap, XAT_HIDDEN);
2185 		}
2186 
2187 		if (XVA_ISSET_REQ(xvap, XAT_NOUNLINK)) {
2188 			xoap->xoa_nounlink =
2189 			    ((pzp->zp_flags & ZFS_NOUNLINK) != 0);
2190 			XVA_SET_RTN(xvap, XAT_NOUNLINK);
2191 		}
2192 
2193 		if (XVA_ISSET_REQ(xvap, XAT_IMMUTABLE)) {
2194 			xoap->xoa_immutable =
2195 			    ((pzp->zp_flags & ZFS_IMMUTABLE) != 0);
2196 			XVA_SET_RTN(xvap, XAT_IMMUTABLE);
2197 		}
2198 
2199 		if (XVA_ISSET_REQ(xvap, XAT_APPENDONLY)) {
2200 			xoap->xoa_appendonly =
2201 			    ((pzp->zp_flags & ZFS_APPENDONLY) != 0);
2202 			XVA_SET_RTN(xvap, XAT_APPENDONLY);
2203 		}
2204 
2205 		if (XVA_ISSET_REQ(xvap, XAT_NODUMP)) {
2206 			xoap->xoa_nodump =
2207 			    ((pzp->zp_flags & ZFS_NODUMP) != 0);
2208 			XVA_SET_RTN(xvap, XAT_NODUMP);
2209 		}
2210 
2211 		if (XVA_ISSET_REQ(xvap, XAT_OPAQUE)) {
2212 			xoap->xoa_opaque =
2213 			    ((pzp->zp_flags & ZFS_OPAQUE) != 0);
2214 			XVA_SET_RTN(xvap, XAT_OPAQUE);
2215 		}
2216 
2217 		if (XVA_ISSET_REQ(xvap, XAT_AV_QUARANTINED)) {
2218 			xoap->xoa_av_quarantined =
2219 			    ((pzp->zp_flags & ZFS_AV_QUARANTINED) != 0);
2220 			XVA_SET_RTN(xvap, XAT_AV_QUARANTINED);
2221 		}
2222 
2223 		if (XVA_ISSET_REQ(xvap, XAT_AV_MODIFIED)) {
2224 			xoap->xoa_av_modified =
2225 			    ((pzp->zp_flags & ZFS_AV_MODIFIED) != 0);
2226 			XVA_SET_RTN(xvap, XAT_AV_MODIFIED);
2227 		}
2228 
2229 		if (XVA_ISSET_REQ(xvap, XAT_AV_SCANSTAMP) &&
2230 		    vp->v_type == VREG &&
2231 		    (pzp->zp_flags & ZFS_BONUS_SCANSTAMP)) {
2232 			size_t len;
2233 			dmu_object_info_t doi;
2234 
2235 			/*
2236 			 * Only VREG files have anti-virus scanstamps, so we
2237 			 * won't conflict with symlinks in the bonus buffer.
2238 			 */
2239 			dmu_object_info_from_db(zp->z_dbuf, &doi);
2240 			len = sizeof (xoap->xoa_av_scanstamp) +
2241 			    sizeof (znode_phys_t);
2242 			if (len <= doi.doi_bonus_size) {
2243 				/*
2244 				 * pzp points to the start of the
2245 				 * znode_phys_t. pzp + 1 points to the
2246 				 * first byte after the znode_phys_t.
2247 				 */
2248 				(void) memcpy(xoap->xoa_av_scanstamp,
2249 				    pzp + 1,
2250 				    sizeof (xoap->xoa_av_scanstamp));
2251 				XVA_SET_RTN(xvap, XAT_AV_SCANSTAMP);
2252 			}
2253 		}
2254 
2255 		if (XVA_ISSET_REQ(xvap, XAT_CREATETIME)) {
2256 			ZFS_TIME_DECODE(&xoap->xoa_createtime, pzp->zp_crtime);
2257 			XVA_SET_RTN(xvap, XAT_CREATETIME);
2258 		}
2259 	}
2260 
2261 	ZFS_TIME_DECODE(&vap->va_atime, pzp->zp_atime);
2262 	ZFS_TIME_DECODE(&vap->va_mtime, pzp->zp_mtime);
2263 	ZFS_TIME_DECODE(&vap->va_ctime, pzp->zp_ctime);
2264 
2265 	mutex_exit(&zp->z_lock);
2266 
2267 	dmu_object_size_from_db(zp->z_dbuf, &vap->va_blksize, &vap->va_nblocks);
2268 
2269 	if (zp->z_blksz == 0) {
2270 		/*
2271 		 * Block size hasn't been set; suggest maximal I/O transfers.
2272 		 */
2273 		vap->va_blksize = zfsvfs->z_max_blksz;
2274 	}
2275 
2276 	ZFS_EXIT(zfsvfs);
2277 	return (0);
2278 }
2279 
2280 /*
2281  * Set the file attributes to the values contained in the
2282  * vattr structure.
2283  *
2284  *	IN:	vp	- vnode of file to be modified.
2285  *		vap	- new attribute values.
2286  *			  If AT_XVATTR set, then optional attrs are being set
2287  *		flags	- ATTR_UTIME set if non-default time values provided.
2288  *			- ATTR_NOACLCHECK (CIFS context only).
2289  *		cr	- credentials of caller.
2290  *		ct	- caller context
2291  *
2292  *	RETURN:	0 if success
2293  *		error code if failure
2294  *
2295  * Timestamps:
2296  *	vp - ctime updated, mtime updated if size changed.
2297  */
2298 /* ARGSUSED */
2299 static int
2300 zfs_setattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr,
2301 	caller_context_t *ct)
2302 {
2303 	znode_t		*zp = VTOZ(vp);
2304 	znode_phys_t	*pzp;
2305 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
2306 	zilog_t		*zilog;
2307 	dmu_tx_t	*tx;
2308 	vattr_t		oldva;
2309 	uint_t		mask = vap->va_mask;
2310 	uint_t		saved_mask;
2311 	int		trim_mask = 0;
2312 	uint64_t	new_mode;
2313 	znode_t		*attrzp;
2314 	int		need_policy = FALSE;
2315 	int		err;
2316 	zfs_fuid_info_t *fuidp = NULL;
2317 	xvattr_t *xvap = (xvattr_t *)vap;	/* vap may be an xvattr_t * */
2318 	xoptattr_t	*xoap;
2319 	boolean_t skipaclchk = (flags & ATTR_NOACLCHECK) ? B_TRUE : B_FALSE;
2320 
2321 	if (mask == 0)
2322 		return (0);
2323 
2324 	if (mask & AT_NOSET)
2325 		return (EINVAL);
2326 
2327 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
2328 
2329 	pzp = zp->z_phys;
2330 	zilog = zfsvfs->z_log;
2331 
2332 	/*
2333 	 * Make sure that if we have ephemeral uid/gid or xvattr specified
2334 	 * that file system is at proper version level
2335 	 */
2336 
2337 	if (zfsvfs->z_use_fuids == B_FALSE &&
2338 	    (((mask & AT_UID) && IS_EPHEMERAL(vap->va_uid)) ||
2339 	    ((mask & AT_GID) && IS_EPHEMERAL(vap->va_gid)) ||
2340 	    (mask & AT_XVATTR)))
2341 		return (EINVAL);
2342 
2343 	if (mask & AT_SIZE && vp->v_type == VDIR)
2344 		return (EISDIR);
2345 
2346 	if (mask & AT_SIZE && vp->v_type != VREG && vp->v_type != VFIFO)
2347 		return (EINVAL);
2348 
2349 	/*
2350 	 * If this is an xvattr_t, then get a pointer to the structure of
2351 	 * optional attributes.  If this is NULL, then we have a vattr_t.
2352 	 */
2353 	xoap = xva_getxoptattr(xvap);
2354 
2355 	/*
2356 	 * Immutable files can only alter immutable bit and atime
2357 	 */
2358 	if ((pzp->zp_flags & ZFS_IMMUTABLE) &&
2359 	    ((mask & (AT_SIZE|AT_UID|AT_GID|AT_MTIME|AT_MODE)) ||
2360 	    ((mask & AT_XVATTR) && XVA_ISSET_REQ(xvap, XAT_CREATETIME))))
2361 		return (EPERM);
2362 
2363 	if ((mask & AT_SIZE) && (pzp->zp_flags & ZFS_READONLY))
2364 		return (EPERM);
2365 
2366 top:
2367 	attrzp = NULL;
2368 
2369 	if (zfsvfs->z_vfs->vfs_flag & VFS_RDONLY) {
2370 		ZFS_EXIT(zfsvfs);
2371 		return (EROFS);
2372 	}
2373 
2374 	/*
2375 	 * First validate permissions
2376 	 */
2377 
2378 	if (mask & AT_SIZE) {
2379 		err = zfs_zaccess(zp, ACE_WRITE_DATA, 0, skipaclchk, cr);
2380 		if (err) {
2381 			ZFS_EXIT(zfsvfs);
2382 			return (err);
2383 		}
2384 		/*
2385 		 * XXX - Note, we are not providing any open
2386 		 * mode flags here (like FNDELAY), so we may
2387 		 * block if there are locks present... this
2388 		 * should be addressed in openat().
2389 		 */
2390 		do {
2391 			err = zfs_freesp(zp, vap->va_size, 0, 0, FALSE);
2392 			/* NB: we already did dmu_tx_wait() if necessary */
2393 		} while (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT);
2394 		if (err) {
2395 			ZFS_EXIT(zfsvfs);
2396 			return (err);
2397 		}
2398 	}
2399 
2400 	if (mask & (AT_ATIME|AT_MTIME) ||
2401 	    ((mask & AT_XVATTR) && (XVA_ISSET_REQ(xvap, XAT_HIDDEN) ||
2402 	    XVA_ISSET_REQ(xvap, XAT_READONLY) ||
2403 	    XVA_ISSET_REQ(xvap, XAT_ARCHIVE) ||
2404 	    XVA_ISSET_REQ(xvap, XAT_CREATETIME) ||
2405 	    XVA_ISSET_REQ(xvap, XAT_SYSTEM))))
2406 		need_policy = zfs_zaccess(zp, ACE_WRITE_ATTRIBUTES, 0,
2407 		    skipaclchk, cr);
2408 
2409 	if (mask & (AT_UID|AT_GID)) {
2410 		int	idmask = (mask & (AT_UID|AT_GID));
2411 		int	take_owner;
2412 		int	take_group;
2413 
2414 		/*
2415 		 * NOTE: even if a new mode is being set,
2416 		 * we may clear S_ISUID/S_ISGID bits.
2417 		 */
2418 
2419 		if (!(mask & AT_MODE))
2420 			vap->va_mode = pzp->zp_mode;
2421 
2422 		/*
2423 		 * Take ownership or chgrp to group we are a member of
2424 		 */
2425 
2426 		take_owner = (mask & AT_UID) && (vap->va_uid == crgetuid(cr));
2427 		take_group = (mask & AT_GID) &&
2428 		    zfs_groupmember(zfsvfs, vap->va_gid, cr);
2429 
2430 		/*
2431 		 * If both AT_UID and AT_GID are set then take_owner and
2432 		 * take_group must both be set in order to allow taking
2433 		 * ownership.
2434 		 *
2435 		 * Otherwise, send the check through secpolicy_vnode_setattr()
2436 		 *
2437 		 */
2438 
2439 		if (((idmask == (AT_UID|AT_GID)) && take_owner && take_group) ||
2440 		    ((idmask == AT_UID) && take_owner) ||
2441 		    ((idmask == AT_GID) && take_group)) {
2442 			if (zfs_zaccess(zp, ACE_WRITE_OWNER, 0,
2443 			    skipaclchk, cr) == 0) {
2444 				/*
2445 				 * Remove setuid/setgid for non-privileged users
2446 				 */
2447 				secpolicy_setid_clear(vap, cr);
2448 				trim_mask = (mask & (AT_UID|AT_GID));
2449 			} else {
2450 				need_policy =  TRUE;
2451 			}
2452 		} else {
2453 			need_policy =  TRUE;
2454 		}
2455 	}
2456 
2457 	mutex_enter(&zp->z_lock);
2458 	oldva.va_mode = pzp->zp_mode;
2459 	zfs_fuid_map_ids(zp, &oldva.va_uid, &oldva.va_gid);
2460 	if (mask & AT_XVATTR) {
2461 		if ((need_policy == FALSE) &&
2462 		    (XVA_ISSET_REQ(xvap, XAT_APPENDONLY) &&
2463 		    xoap->xoa_appendonly !=
2464 		    ((pzp->zp_flags & ZFS_APPENDONLY) != 0)) ||
2465 		    (XVA_ISSET_REQ(xvap, XAT_NOUNLINK) &&
2466 		    xoap->xoa_nounlink !=
2467 		    ((pzp->zp_flags & ZFS_NOUNLINK) != 0)) ||
2468 		    (XVA_ISSET_REQ(xvap, XAT_IMMUTABLE) &&
2469 		    xoap->xoa_immutable !=
2470 		    ((pzp->zp_flags & ZFS_IMMUTABLE) != 0)) ||
2471 		    (XVA_ISSET_REQ(xvap, XAT_NODUMP) &&
2472 		    xoap->xoa_nodump !=
2473 		    ((pzp->zp_flags & ZFS_NODUMP) != 0)) ||
2474 		    (XVA_ISSET_REQ(xvap, XAT_AV_MODIFIED) &&
2475 		    xoap->xoa_av_modified !=
2476 		    ((pzp->zp_flags & ZFS_AV_MODIFIED) != 0)) ||
2477 		    (XVA_ISSET_REQ(xvap, XAT_AV_QUARANTINED) &&
2478 		    xoap->xoa_av_quarantined !=
2479 		    ((pzp->zp_flags & ZFS_AV_QUARANTINED) != 0)) ||
2480 		    (XVA_ISSET_REQ(xvap, XAT_AV_SCANSTAMP)) ||
2481 		    (XVA_ISSET_REQ(xvap, XAT_OPAQUE))) {
2482 			need_policy = TRUE;
2483 		}
2484 	}
2485 
2486 	mutex_exit(&zp->z_lock);
2487 
2488 	if (mask & AT_MODE) {
2489 		if (zfs_zaccess(zp, ACE_WRITE_ACL, 0, skipaclchk, cr) == 0) {
2490 			err = secpolicy_setid_setsticky_clear(vp, vap,
2491 			    &oldva, cr);
2492 			if (err) {
2493 				ZFS_EXIT(zfsvfs);
2494 				return (err);
2495 			}
2496 			trim_mask |= AT_MODE;
2497 		} else {
2498 			need_policy = TRUE;
2499 		}
2500 	}
2501 
2502 	if (need_policy) {
2503 		/*
2504 		 * If trim_mask is set then take ownership
2505 		 * has been granted or write_acl is present and user
2506 		 * has the ability to modify mode.  In that case remove
2507 		 * UID|GID and or MODE from mask so that
2508 		 * secpolicy_vnode_setattr() doesn't revoke it.
2509 		 */
2510 
2511 		if (trim_mask) {
2512 			saved_mask = vap->va_mask;
2513 			vap->va_mask &= ~trim_mask;
2514 		}
2515 		err = secpolicy_vnode_setattr(cr, vp, vap, &oldva, flags,
2516 		    (int (*)(void *, int, cred_t *))zfs_zaccess_unix, zp);
2517 		if (err) {
2518 			ZFS_EXIT(zfsvfs);
2519 			return (err);
2520 		}
2521 
2522 		if (trim_mask)
2523 			vap->va_mask |= saved_mask;
2524 	}
2525 
2526 	/*
2527 	 * secpolicy_vnode_setattr, or take ownership may have
2528 	 * changed va_mask
2529 	 */
2530 	mask = vap->va_mask;
2531 
2532 	tx = dmu_tx_create(zfsvfs->z_os);
2533 	dmu_tx_hold_bonus(tx, zp->z_id);
2534 	if (zfsvfs->z_fuid_obj == 0) {
2535 		dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT);
2536 		dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0,
2537 		    SPA_MAXBLOCKSIZE);
2538 		dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, FALSE, NULL);
2539 	} else {
2540 		dmu_tx_hold_bonus(tx, zfsvfs->z_fuid_obj);
2541 		dmu_tx_hold_write(tx, zfsvfs->z_fuid_obj, 0,
2542 		    SPA_MAXBLOCKSIZE);
2543 	}
2544 
2545 	if (mask & AT_MODE) {
2546 		uint64_t pmode = pzp->zp_mode;
2547 
2548 		new_mode = (pmode & S_IFMT) | (vap->va_mode & ~S_IFMT);
2549 
2550 		if (pzp->zp_acl.z_acl_extern_obj) {
2551 			/* Are we upgrading ACL from old V0 format to new V1 */
2552 			if (zfsvfs->z_version <= ZPL_VERSION_FUID &&
2553 			    pzp->zp_acl.z_acl_version ==
2554 			    ZFS_ACL_VERSION_INITIAL) {
2555 				dmu_tx_hold_free(tx,
2556 				    pzp->zp_acl.z_acl_extern_obj, 0,
2557 				    DMU_OBJECT_END);
2558 				dmu_tx_hold_write(tx, DMU_NEW_OBJECT,
2559 				    0, sizeof (zfs_object_ace_t) * 2048 + 6);
2560 			} else {
2561 				dmu_tx_hold_write(tx,
2562 				    pzp->zp_acl.z_acl_extern_obj, 0,
2563 				    SPA_MAXBLOCKSIZE);
2564 			}
2565 		} else {
2566 			dmu_tx_hold_write(tx, DMU_NEW_OBJECT,
2567 			    0, sizeof (zfs_object_ace_t) * 2048 + 6);
2568 		}
2569 	}
2570 
2571 	if ((mask & (AT_UID | AT_GID)) && pzp->zp_xattr != 0) {
2572 		err = zfs_zget(zp->z_zfsvfs, pzp->zp_xattr, &attrzp);
2573 		if (err) {
2574 			dmu_tx_abort(tx);
2575 			ZFS_EXIT(zfsvfs);
2576 			return (err);
2577 		}
2578 		dmu_tx_hold_bonus(tx, attrzp->z_id);
2579 	}
2580 
2581 	err = dmu_tx_assign(tx, zfsvfs->z_assign);
2582 	if (err) {
2583 		if (attrzp)
2584 			VN_RELE(ZTOV(attrzp));
2585 		if (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
2586 			dmu_tx_wait(tx);
2587 			dmu_tx_abort(tx);
2588 			goto top;
2589 		}
2590 		dmu_tx_abort(tx);
2591 		ZFS_EXIT(zfsvfs);
2592 		return (err);
2593 	}
2594 
2595 	dmu_buf_will_dirty(zp->z_dbuf, tx);
2596 
2597 	/*
2598 	 * Set each attribute requested.
2599 	 * We group settings according to the locks they need to acquire.
2600 	 *
2601 	 * Note: you cannot set ctime directly, although it will be
2602 	 * updated as a side-effect of calling this function.
2603 	 */
2604 
2605 	mutex_enter(&zp->z_lock);
2606 
2607 	if (mask & AT_MODE) {
2608 		err = zfs_acl_chmod_setattr(zp, new_mode, tx);
2609 		ASSERT3U(err, ==, 0);
2610 	}
2611 
2612 	if (attrzp)
2613 		mutex_enter(&attrzp->z_lock);
2614 
2615 	if (mask & AT_UID) {
2616 		pzp->zp_uid = zfs_fuid_create(zfsvfs,
2617 		    vap->va_uid, ZFS_OWNER, tx, &fuidp);
2618 		if (attrzp) {
2619 			attrzp->z_phys->zp_uid = zfs_fuid_create(zfsvfs,
2620 			    vap->va_uid,  ZFS_OWNER, tx, &fuidp);
2621 		}
2622 	}
2623 
2624 	if (mask & AT_GID) {
2625 		pzp->zp_gid = zfs_fuid_create(zfsvfs, vap->va_gid,
2626 		    ZFS_GROUP, tx, &fuidp);
2627 		if (attrzp)
2628 			attrzp->z_phys->zp_gid = zfs_fuid_create(zfsvfs,
2629 			    vap->va_gid, ZFS_GROUP, tx, &fuidp);
2630 	}
2631 
2632 	if (attrzp)
2633 		mutex_exit(&attrzp->z_lock);
2634 
2635 	if (mask & AT_ATIME)
2636 		ZFS_TIME_ENCODE(&vap->va_atime, pzp->zp_atime);
2637 
2638 	if (mask & AT_MTIME)
2639 		ZFS_TIME_ENCODE(&vap->va_mtime, pzp->zp_mtime);
2640 
2641 	if (mask & AT_SIZE)
2642 		zfs_time_stamper_locked(zp, CONTENT_MODIFIED, tx);
2643 	else if (mask != 0)
2644 		zfs_time_stamper_locked(zp, STATE_CHANGED, tx);
2645 	/*
2646 	 * Do this after setting timestamps to prevent timestamp
2647 	 * update from toggling bit
2648 	 */
2649 
2650 	if (xoap && (mask & AT_XVATTR)) {
2651 		if (XVA_ISSET_REQ(xvap, XAT_AV_SCANSTAMP)) {
2652 			size_t len;
2653 			dmu_object_info_t doi;
2654 
2655 			ASSERT(vp->v_type == VREG);
2656 
2657 			/* Grow the bonus buffer if necessary. */
2658 			dmu_object_info_from_db(zp->z_dbuf, &doi);
2659 			len = sizeof (xoap->xoa_av_scanstamp) +
2660 			    sizeof (znode_phys_t);
2661 			if (len > doi.doi_bonus_size)
2662 				VERIFY(dmu_set_bonus(zp->z_dbuf, len, tx) == 0);
2663 		}
2664 		zfs_xvattr_set(zp, xvap);
2665 	}
2666 
2667 	if (mask != 0)
2668 		zfs_log_setattr(zilog, tx, TX_SETATTR, zp, vap, mask, fuidp);
2669 
2670 	if (fuidp)
2671 		zfs_fuid_info_free(fuidp);
2672 	mutex_exit(&zp->z_lock);
2673 
2674 	if (attrzp)
2675 		VN_RELE(ZTOV(attrzp));
2676 
2677 	dmu_tx_commit(tx);
2678 
2679 	ZFS_EXIT(zfsvfs);
2680 	return (err);
2681 }
2682 
2683 typedef struct zfs_zlock {
2684 	krwlock_t	*zl_rwlock;	/* lock we acquired */
2685 	znode_t		*zl_znode;	/* znode we held */
2686 	struct zfs_zlock *zl_next;	/* next in list */
2687 } zfs_zlock_t;
2688 
2689 /*
2690  * Drop locks and release vnodes that were held by zfs_rename_lock().
2691  */
2692 static void
2693 zfs_rename_unlock(zfs_zlock_t **zlpp)
2694 {
2695 	zfs_zlock_t *zl;
2696 
2697 	while ((zl = *zlpp) != NULL) {
2698 		if (zl->zl_znode != NULL)
2699 			VN_RELE(ZTOV(zl->zl_znode));
2700 		rw_exit(zl->zl_rwlock);
2701 		*zlpp = zl->zl_next;
2702 		kmem_free(zl, sizeof (*zl));
2703 	}
2704 }
2705 
2706 /*
2707  * Search back through the directory tree, using the ".." entries.
2708  * Lock each directory in the chain to prevent concurrent renames.
2709  * Fail any attempt to move a directory into one of its own descendants.
2710  * XXX - z_parent_lock can overlap with map or grow locks
2711  */
2712 static int
2713 zfs_rename_lock(znode_t *szp, znode_t *tdzp, znode_t *sdzp, zfs_zlock_t **zlpp)
2714 {
2715 	zfs_zlock_t	*zl;
2716 	znode_t		*zp = tdzp;
2717 	uint64_t	rootid = zp->z_zfsvfs->z_root;
2718 	uint64_t	*oidp = &zp->z_id;
2719 	krwlock_t	*rwlp = &szp->z_parent_lock;
2720 	krw_t		rw = RW_WRITER;
2721 
2722 	/*
2723 	 * First pass write-locks szp and compares to zp->z_id.
2724 	 * Later passes read-lock zp and compare to zp->z_parent.
2725 	 */
2726 	do {
2727 		if (!rw_tryenter(rwlp, rw)) {
2728 			/*
2729 			 * Another thread is renaming in this path.
2730 			 * Note that if we are a WRITER, we don't have any
2731 			 * parent_locks held yet.
2732 			 */
2733 			if (rw == RW_READER && zp->z_id > szp->z_id) {
2734 				/*
2735 				 * Drop our locks and restart
2736 				 */
2737 				zfs_rename_unlock(&zl);
2738 				*zlpp = NULL;
2739 				zp = tdzp;
2740 				oidp = &zp->z_id;
2741 				rwlp = &szp->z_parent_lock;
2742 				rw = RW_WRITER;
2743 				continue;
2744 			} else {
2745 				/*
2746 				 * Wait for other thread to drop its locks
2747 				 */
2748 				rw_enter(rwlp, rw);
2749 			}
2750 		}
2751 
2752 		zl = kmem_alloc(sizeof (*zl), KM_SLEEP);
2753 		zl->zl_rwlock = rwlp;
2754 		zl->zl_znode = NULL;
2755 		zl->zl_next = *zlpp;
2756 		*zlpp = zl;
2757 
2758 		if (*oidp == szp->z_id)		/* We're a descendant of szp */
2759 			return (EINVAL);
2760 
2761 		if (*oidp == rootid)		/* We've hit the top */
2762 			return (0);
2763 
2764 		if (rw == RW_READER) {		/* i.e. not the first pass */
2765 			int error = zfs_zget(zp->z_zfsvfs, *oidp, &zp);
2766 			if (error)
2767 				return (error);
2768 			zl->zl_znode = zp;
2769 		}
2770 		oidp = &zp->z_phys->zp_parent;
2771 		rwlp = &zp->z_parent_lock;
2772 		rw = RW_READER;
2773 
2774 	} while (zp->z_id != sdzp->z_id);
2775 
2776 	return (0);
2777 }
2778 
2779 /*
2780  * Move an entry from the provided source directory to the target
2781  * directory.  Change the entry name as indicated.
2782  *
2783  *	IN:	sdvp	- Source directory containing the "old entry".
2784  *		snm	- Old entry name.
2785  *		tdvp	- Target directory to contain the "new entry".
2786  *		tnm	- New entry name.
2787  *		cr	- credentials of caller.
2788  *		ct	- caller context
2789  *		flags	- case flags
2790  *
2791  *	RETURN:	0 if success
2792  *		error code if failure
2793  *
2794  * Timestamps:
2795  *	sdvp,tdvp - ctime|mtime updated
2796  */
2797 /*ARGSUSED*/
2798 static int
2799 zfs_rename(vnode_t *sdvp, char *snm, vnode_t *tdvp, char *tnm, cred_t *cr,
2800     caller_context_t *ct, int flags)
2801 {
2802 	znode_t		*tdzp, *szp, *tzp;
2803 	znode_t		*sdzp = VTOZ(sdvp);
2804 	zfsvfs_t	*zfsvfs = sdzp->z_zfsvfs;
2805 	zilog_t		*zilog;
2806 	vnode_t		*realvp;
2807 	zfs_dirlock_t	*sdl, *tdl;
2808 	dmu_tx_t	*tx;
2809 	zfs_zlock_t	*zl;
2810 	int		cmp, serr, terr;
2811 	int		error = 0;
2812 	int		zflg = 0;
2813 
2814 	ZFS_ENTER_VERIFY_ZP(zfsvfs, sdzp);
2815 	zilog = zfsvfs->z_log;
2816 
2817 	/*
2818 	 * Make sure we have the real vp for the target directory.
2819 	 */
2820 	if (VOP_REALVP(tdvp, &realvp, ct) == 0)
2821 		tdvp = realvp;
2822 
2823 	if (tdvp->v_vfsp != sdvp->v_vfsp) {
2824 		ZFS_EXIT(zfsvfs);
2825 		return (EXDEV);
2826 	}
2827 
2828 	tdzp = VTOZ(tdvp);
2829 	if (!tdzp->z_dbuf_held) {
2830 		ZFS_EXIT(zfsvfs);
2831 		return (EIO);
2832 	}
2833 	if (zfsvfs->z_case & ZFS_UTF8_ONLY && u8_validate(tnm,
2834 	    strlen(tnm), NULL, U8_VALIDATE_ENTIRE, &error) < 0) {
2835 		ZFS_EXIT(zfsvfs);
2836 		return (EILSEQ);
2837 	}
2838 
2839 	if (flags & FIGNORECASE)
2840 		zflg |= ZCILOOK;
2841 
2842 top:
2843 	szp = NULL;
2844 	tzp = NULL;
2845 	zl = NULL;
2846 
2847 	/*
2848 	 * This is to prevent the creation of links into attribute space
2849 	 * by renaming a linked file into/outof an attribute directory.
2850 	 * See the comment in zfs_link() for why this is considered bad.
2851 	 */
2852 	if ((tdzp->z_phys->zp_flags & ZFS_XATTR) !=
2853 	    (sdzp->z_phys->zp_flags & ZFS_XATTR)) {
2854 		ZFS_EXIT(zfsvfs);
2855 		return (EINVAL);
2856 	}
2857 
2858 	/*
2859 	 * Lock source and target directory entries.  To prevent deadlock,
2860 	 * a lock ordering must be defined.  We lock the directory with
2861 	 * the smallest object id first, or if it's a tie, the one with
2862 	 * the lexically first name.
2863 	 */
2864 	if (sdzp->z_id < tdzp->z_id) {
2865 		cmp = -1;
2866 	} else if (sdzp->z_id > tdzp->z_id) {
2867 		cmp = 1;
2868 	} else {
2869 		/*
2870 		 * First compare the two name arguments without
2871 		 * considering any case folding.
2872 		 */
2873 		int nofold = (zfsvfs->z_norm & ~U8_TEXTPREP_TOUPPER);
2874 
2875 		cmp = u8_strcmp(snm, tnm, 0, nofold, U8_UNICODE_LATEST, &error);
2876 		ASSERT(error == 0 || !(zfsvfs->z_case & ZFS_UTF8_ONLY));
2877 		if (cmp == 0) {
2878 			/*
2879 			 * POSIX: "If the old argument and the new argument
2880 			 * both refer to links to the same existing file,
2881 			 * the rename() function shall return successfully
2882 			 * and perform no other action."
2883 			 */
2884 			ZFS_EXIT(zfsvfs);
2885 			return (0);
2886 		}
2887 		/*
2888 		 * If the file system is case-folding, then we may
2889 		 * have some more checking to do.  A case-folding file
2890 		 * system is either supporting mixed case sensitivity
2891 		 * access or is completely case-insensitive.  Note
2892 		 * that the file system is always case preserving.
2893 		 *
2894 		 * In mixed sensitivity mode case sensitive behavior
2895 		 * is the default.  FIGNORECASE must be used to
2896 		 * explicitly request case insensitive behavior.
2897 		 *
2898 		 * If the source and target names provided differ only
2899 		 * by case (e.g., a request to rename 'tim' to 'Tim'),
2900 		 * we will treat this as a special case in the
2901 		 * case-insensitive mode: as long as the source name
2902 		 * is an exact match, we will allow this to proceed as
2903 		 * a name-change request.
2904 		 */
2905 		if ((zfsvfs->z_case & ZFS_CI_ONLY ||
2906 		    (zfsvfs->z_case & ZFS_CI_MIXD && flags & FIGNORECASE)) &&
2907 		    u8_strcmp(snm, tnm, 0, zfsvfs->z_norm, U8_UNICODE_LATEST,
2908 		    &error) == 0) {
2909 			/*
2910 			 * case preserving rename request, require exact
2911 			 * name matches
2912 			 */
2913 			zflg |= ZCIEXACT;
2914 			zflg &= ~ZCILOOK;
2915 		}
2916 	}
2917 
2918 	if (cmp < 0) {
2919 		serr = zfs_dirent_lock(&sdl, sdzp, snm, &szp,
2920 		    ZEXISTS | zflg, NULL, NULL);
2921 		terr = zfs_dirent_lock(&tdl,
2922 		    tdzp, tnm, &tzp, ZRENAMING | zflg, NULL, NULL);
2923 	} else {
2924 		terr = zfs_dirent_lock(&tdl,
2925 		    tdzp, tnm, &tzp, zflg, NULL, NULL);
2926 		serr = zfs_dirent_lock(&sdl,
2927 		    sdzp, snm, &szp, ZEXISTS | ZRENAMING | zflg,
2928 		    NULL, NULL);
2929 	}
2930 
2931 	if (serr) {
2932 		/*
2933 		 * Source entry invalid or not there.
2934 		 */
2935 		if (!terr) {
2936 			zfs_dirent_unlock(tdl);
2937 			if (tzp)
2938 				VN_RELE(ZTOV(tzp));
2939 		}
2940 		if (strcmp(snm, "..") == 0)
2941 			serr = EINVAL;
2942 		ZFS_EXIT(zfsvfs);
2943 		return (serr);
2944 	}
2945 	if (terr) {
2946 		zfs_dirent_unlock(sdl);
2947 		VN_RELE(ZTOV(szp));
2948 		if (strcmp(tnm, "..") == 0)
2949 			terr = EINVAL;
2950 		ZFS_EXIT(zfsvfs);
2951 		return (terr);
2952 	}
2953 
2954 	/*
2955 	 * Must have write access at the source to remove the old entry
2956 	 * and write access at the target to create the new entry.
2957 	 * Note that if target and source are the same, this can be
2958 	 * done in a single check.
2959 	 */
2960 
2961 	if (error = zfs_zaccess_rename(sdzp, szp, tdzp, tzp, cr))
2962 		goto out;
2963 
2964 	if (ZTOV(szp)->v_type == VDIR) {
2965 		/*
2966 		 * Check to make sure rename is valid.
2967 		 * Can't do a move like this: /usr/a/b to /usr/a/b/c/d
2968 		 */
2969 		if (error = zfs_rename_lock(szp, tdzp, sdzp, &zl))
2970 			goto out;
2971 	}
2972 
2973 	/*
2974 	 * Does target exist?
2975 	 */
2976 	if (tzp) {
2977 		/*
2978 		 * Source and target must be the same type.
2979 		 */
2980 		if (ZTOV(szp)->v_type == VDIR) {
2981 			if (ZTOV(tzp)->v_type != VDIR) {
2982 				error = ENOTDIR;
2983 				goto out;
2984 			}
2985 		} else {
2986 			if (ZTOV(tzp)->v_type == VDIR) {
2987 				error = EISDIR;
2988 				goto out;
2989 			}
2990 		}
2991 		/*
2992 		 * POSIX dictates that when the source and target
2993 		 * entries refer to the same file object, rename
2994 		 * must do nothing and exit without error.
2995 		 */
2996 		if (szp->z_id == tzp->z_id) {
2997 			error = 0;
2998 			goto out;
2999 		}
3000 	}
3001 
3002 	vnevent_rename_src(ZTOV(szp), sdvp, snm, ct);
3003 	if (tzp)
3004 		vnevent_rename_dest(ZTOV(tzp), tdvp, tnm, ct);
3005 
3006 	/*
3007 	 * notify the target directory if it is not the same
3008 	 * as source directory.
3009 	 */
3010 	if (tdvp != sdvp) {
3011 		vnevent_rename_dest_dir(tdvp, ct);
3012 	}
3013 
3014 	tx = dmu_tx_create(zfsvfs->z_os);
3015 	dmu_tx_hold_bonus(tx, szp->z_id);	/* nlink changes */
3016 	dmu_tx_hold_bonus(tx, sdzp->z_id);	/* nlink changes */
3017 	dmu_tx_hold_zap(tx, sdzp->z_id, FALSE, snm);
3018 	dmu_tx_hold_zap(tx, tdzp->z_id, TRUE, tnm);
3019 	if (sdzp != tdzp)
3020 		dmu_tx_hold_bonus(tx, tdzp->z_id);	/* nlink changes */
3021 	if (tzp)
3022 		dmu_tx_hold_bonus(tx, tzp->z_id);	/* parent changes */
3023 	dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
3024 	error = dmu_tx_assign(tx, zfsvfs->z_assign);
3025 	if (error) {
3026 		if (zl != NULL)
3027 			zfs_rename_unlock(&zl);
3028 		zfs_dirent_unlock(sdl);
3029 		zfs_dirent_unlock(tdl);
3030 		VN_RELE(ZTOV(szp));
3031 		if (tzp)
3032 			VN_RELE(ZTOV(tzp));
3033 		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
3034 			dmu_tx_wait(tx);
3035 			dmu_tx_abort(tx);
3036 			goto top;
3037 		}
3038 		dmu_tx_abort(tx);
3039 		ZFS_EXIT(zfsvfs);
3040 		return (error);
3041 	}
3042 
3043 	if (tzp)	/* Attempt to remove the existing target */
3044 		error = zfs_link_destroy(tdl, tzp, tx, zflg, NULL);
3045 
3046 	if (error == 0) {
3047 		error = zfs_link_create(tdl, szp, tx, ZRENAMING);
3048 		if (error == 0) {
3049 			szp->z_phys->zp_flags |= ZFS_AV_MODIFIED;
3050 
3051 			error = zfs_link_destroy(sdl, szp, tx, ZRENAMING, NULL);
3052 			ASSERT(error == 0);
3053 
3054 			zfs_log_rename(zilog, tx,
3055 			    TX_RENAME | (flags & FIGNORECASE ? TX_CI : 0),
3056 			    sdzp, sdl->dl_name, tdzp, tdl->dl_name, szp);
3057 		}
3058 	}
3059 
3060 	dmu_tx_commit(tx);
3061 out:
3062 	if (zl != NULL)
3063 		zfs_rename_unlock(&zl);
3064 
3065 	zfs_dirent_unlock(sdl);
3066 	zfs_dirent_unlock(tdl);
3067 
3068 	VN_RELE(ZTOV(szp));
3069 	if (tzp)
3070 		VN_RELE(ZTOV(tzp));
3071 
3072 	ZFS_EXIT(zfsvfs);
3073 	return (error);
3074 }
3075 
3076 /*
3077  * Insert the indicated symbolic reference entry into the directory.
3078  *
3079  *	IN:	dvp	- Directory to contain new symbolic link.
3080  *		link	- Name for new symlink entry.
3081  *		vap	- Attributes of new entry.
3082  *		target	- Target path of new symlink.
3083  *		cr	- credentials of caller.
3084  *		ct	- caller context
3085  *		flags	- case flags
3086  *
3087  *	RETURN:	0 if success
3088  *		error code if failure
3089  *
3090  * Timestamps:
3091  *	dvp - ctime|mtime updated
3092  */
3093 /*ARGSUSED*/
3094 static int
3095 zfs_symlink(vnode_t *dvp, char *name, vattr_t *vap, char *link, cred_t *cr,
3096     caller_context_t *ct, int flags)
3097 {
3098 	znode_t		*zp, *dzp = VTOZ(dvp);
3099 	zfs_dirlock_t	*dl;
3100 	dmu_tx_t	*tx;
3101 	zfsvfs_t	*zfsvfs = dzp->z_zfsvfs;
3102 	zilog_t		*zilog;
3103 	uint64_t	zoid;
3104 	int		len = strlen(link);
3105 	int		error;
3106 	int		zflg = ZNEW;
3107 	zfs_fuid_info_t *fuidp = NULL;
3108 
3109 	ASSERT(vap->va_type == VLNK);
3110 
3111 	ZFS_ENTER_VERIFY_ZP(zfsvfs, dzp);
3112 	zilog = zfsvfs->z_log;
3113 
3114 	if (zfsvfs->z_case & ZFS_UTF8_ONLY && u8_validate(name, strlen(name),
3115 	    NULL, U8_VALIDATE_ENTIRE, &error) < 0) {
3116 		ZFS_EXIT(zfsvfs);
3117 		return (EILSEQ);
3118 	}
3119 	if (flags & FIGNORECASE)
3120 		zflg |= ZCILOOK;
3121 top:
3122 	if (error = zfs_zaccess(dzp, ACE_ADD_FILE, 0, B_FALSE, cr)) {
3123 		ZFS_EXIT(zfsvfs);
3124 		return (error);
3125 	}
3126 
3127 	if (len > MAXPATHLEN) {
3128 		ZFS_EXIT(zfsvfs);
3129 		return (ENAMETOOLONG);
3130 	}
3131 
3132 	/*
3133 	 * Attempt to lock directory; fail if entry already exists.
3134 	 */
3135 	error = zfs_dirent_lock(&dl, dzp, name, &zp, zflg, NULL, NULL);
3136 	if (error) {
3137 		ZFS_EXIT(zfsvfs);
3138 		return (error);
3139 	}
3140 
3141 	tx = dmu_tx_create(zfsvfs->z_os);
3142 	dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, MAX(1, len));
3143 	dmu_tx_hold_bonus(tx, dzp->z_id);
3144 	dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name);
3145 	if (dzp->z_phys->zp_flags & ZFS_INHERIT_ACE)
3146 		dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, SPA_MAXBLOCKSIZE);
3147 	if (zfsvfs->z_fuid_obj == 0) {
3148 		dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT);
3149 		dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0,
3150 		    SPA_MAXBLOCKSIZE);
3151 		dmu_tx_hold_zap(tx, MASTER_NODE_OBJ, FALSE, NULL);
3152 	} else {
3153 		dmu_tx_hold_bonus(tx, zfsvfs->z_fuid_obj);
3154 		dmu_tx_hold_write(tx, zfsvfs->z_fuid_obj, 0,
3155 		    SPA_MAXBLOCKSIZE);
3156 	}
3157 	error = dmu_tx_assign(tx, zfsvfs->z_assign);
3158 	if (error) {
3159 		zfs_dirent_unlock(dl);
3160 		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
3161 			dmu_tx_wait(tx);
3162 			dmu_tx_abort(tx);
3163 			goto top;
3164 		}
3165 		dmu_tx_abort(tx);
3166 		ZFS_EXIT(zfsvfs);
3167 		return (error);
3168 	}
3169 
3170 	dmu_buf_will_dirty(dzp->z_dbuf, tx);
3171 
3172 	/*
3173 	 * Create a new object for the symlink.
3174 	 * Put the link content into bonus buffer if it will fit;
3175 	 * otherwise, store it just like any other file data.
3176 	 */
3177 	zoid = 0;
3178 	if (sizeof (znode_phys_t) + len <= dmu_bonus_max()) {
3179 		zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, len, NULL, &fuidp);
3180 		if (len != 0)
3181 			bcopy(link, zp->z_phys + 1, len);
3182 	} else {
3183 		dmu_buf_t *dbp;
3184 
3185 		zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0, NULL, &fuidp);
3186 		/*
3187 		 * Nothing can access the znode yet so no locking needed
3188 		 * for growing the znode's blocksize.
3189 		 */
3190 		zfs_grow_blocksize(zp, len, tx);
3191 
3192 		VERIFY(0 == dmu_buf_hold(zfsvfs->z_os, zoid, 0, FTAG, &dbp));
3193 		dmu_buf_will_dirty(dbp, tx);
3194 
3195 		ASSERT3U(len, <=, dbp->db_size);
3196 		bcopy(link, dbp->db_data, len);
3197 		dmu_buf_rele(dbp, FTAG);
3198 	}
3199 	zp->z_phys->zp_size = len;
3200 
3201 	/*
3202 	 * Insert the new object into the directory.
3203 	 */
3204 	(void) zfs_link_create(dl, zp, tx, ZNEW);
3205 out:
3206 	if (error == 0) {
3207 		uint64_t txtype = TX_SYMLINK;
3208 		if (flags & FIGNORECASE)
3209 			txtype |= TX_CI;
3210 		zfs_log_symlink(zilog, tx, txtype, dzp, zp, name, link);
3211 	}
3212 	if (fuidp)
3213 		zfs_fuid_info_free(fuidp);
3214 
3215 	dmu_tx_commit(tx);
3216 
3217 	zfs_dirent_unlock(dl);
3218 
3219 	VN_RELE(ZTOV(zp));
3220 
3221 	ZFS_EXIT(zfsvfs);
3222 	return (error);
3223 }
3224 
3225 /*
3226  * Return, in the buffer contained in the provided uio structure,
3227  * the symbolic path referred to by vp.
3228  *
3229  *	IN:	vp	- vnode of symbolic link.
3230  *		uoip	- structure to contain the link path.
3231  *		cr	- credentials of caller.
3232  *		ct	- caller context
3233  *
3234  *	OUT:	uio	- structure to contain the link path.
3235  *
3236  *	RETURN:	0 if success
3237  *		error code if failure
3238  *
3239  * Timestamps:
3240  *	vp - atime updated
3241  */
3242 /* ARGSUSED */
3243 static int
3244 zfs_readlink(vnode_t *vp, uio_t *uio, cred_t *cr, caller_context_t *ct)
3245 {
3246 	znode_t		*zp = VTOZ(vp);
3247 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
3248 	size_t		bufsz;
3249 	int		error;
3250 
3251 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
3252 
3253 	bufsz = (size_t)zp->z_phys->zp_size;
3254 	if (bufsz + sizeof (znode_phys_t) <= zp->z_dbuf->db_size) {
3255 		error = uiomove(zp->z_phys + 1,
3256 		    MIN((size_t)bufsz, uio->uio_resid), UIO_READ, uio);
3257 	} else {
3258 		dmu_buf_t *dbp;
3259 		error = dmu_buf_hold(zfsvfs->z_os, zp->z_id, 0, FTAG, &dbp);
3260 		if (error) {
3261 			ZFS_EXIT(zfsvfs);
3262 			return (error);
3263 		}
3264 		error = uiomove(dbp->db_data,
3265 		    MIN((size_t)bufsz, uio->uio_resid), UIO_READ, uio);
3266 		dmu_buf_rele(dbp, FTAG);
3267 	}
3268 
3269 	ZFS_ACCESSTIME_STAMP(zfsvfs, zp);
3270 	ZFS_EXIT(zfsvfs);
3271 	return (error);
3272 }
3273 
3274 /*
3275  * Insert a new entry into directory tdvp referencing svp.
3276  *
3277  *	IN:	tdvp	- Directory to contain new entry.
3278  *		svp	- vnode of new entry.
3279  *		name	- name of new entry.
3280  *		cr	- credentials of caller.
3281  *		ct	- caller context
3282  *
3283  *	RETURN:	0 if success
3284  *		error code if failure
3285  *
3286  * Timestamps:
3287  *	tdvp - ctime|mtime updated
3288  *	 svp - ctime updated
3289  */
3290 /* ARGSUSED */
3291 static int
3292 zfs_link(vnode_t *tdvp, vnode_t *svp, char *name, cred_t *cr,
3293     caller_context_t *ct, int flags)
3294 {
3295 	znode_t		*dzp = VTOZ(tdvp);
3296 	znode_t		*tzp, *szp;
3297 	zfsvfs_t	*zfsvfs = dzp->z_zfsvfs;
3298 	zilog_t		*zilog;
3299 	zfs_dirlock_t	*dl;
3300 	dmu_tx_t	*tx;
3301 	vnode_t		*realvp;
3302 	int		error;
3303 	int		zf = ZNEW;
3304 	uid_t		owner;
3305 
3306 	ASSERT(tdvp->v_type == VDIR);
3307 
3308 	ZFS_ENTER_VERIFY_ZP(zfsvfs, dzp);
3309 	zilog = zfsvfs->z_log;
3310 
3311 	if (VOP_REALVP(svp, &realvp, ct) == 0)
3312 		svp = realvp;
3313 
3314 	if (svp->v_vfsp != tdvp->v_vfsp) {
3315 		ZFS_EXIT(zfsvfs);
3316 		return (EXDEV);
3317 	}
3318 
3319 	if (zfsvfs->z_case & ZFS_UTF8_ONLY && u8_validate(name,
3320 	    strlen(name), NULL, U8_VALIDATE_ENTIRE, &error) < 0) {
3321 		ZFS_EXIT(zfsvfs);
3322 		return (EILSEQ);
3323 	}
3324 	if (flags & FIGNORECASE)
3325 		zf |= ZCILOOK;
3326 
3327 	szp = VTOZ(svp);
3328 	if (!szp->z_dbuf_held) {
3329 		ZFS_EXIT(zfsvfs);
3330 		return (EIO);
3331 	}
3332 top:
3333 	/*
3334 	 * We do not support links between attributes and non-attributes
3335 	 * because of the potential security risk of creating links
3336 	 * into "normal" file space in order to circumvent restrictions
3337 	 * imposed in attribute space.
3338 	 */
3339 	if ((szp->z_phys->zp_flags & ZFS_XATTR) !=
3340 	    (dzp->z_phys->zp_flags & ZFS_XATTR)) {
3341 		ZFS_EXIT(zfsvfs);
3342 		return (EINVAL);
3343 	}
3344 
3345 	/*
3346 	 * POSIX dictates that we return EPERM here.
3347 	 * Better choices include ENOTSUP or EISDIR.
3348 	 */
3349 	if (svp->v_type == VDIR) {
3350 		ZFS_EXIT(zfsvfs);
3351 		return (EPERM);
3352 	}
3353 
3354 	zfs_fuid_map_id(zfsvfs, szp->z_phys->zp_uid, ZFS_OWNER, &owner);
3355 	if (owner != crgetuid(cr) &&
3356 	    secpolicy_basic_link(cr) != 0) {
3357 		ZFS_EXIT(zfsvfs);
3358 		return (EPERM);
3359 	}
3360 
3361 	if (error = zfs_zaccess(dzp, ACE_ADD_FILE, 0, B_FALSE, cr)) {
3362 		ZFS_EXIT(zfsvfs);
3363 		return (error);
3364 	}
3365 
3366 	/*
3367 	 * Attempt to lock directory; fail if entry already exists.
3368 	 */
3369 	error = zfs_dirent_lock(&dl, dzp, name, &tzp, zf, NULL, NULL);
3370 	if (error) {
3371 		ZFS_EXIT(zfsvfs);
3372 		return (error);
3373 	}
3374 
3375 	tx = dmu_tx_create(zfsvfs->z_os);
3376 	dmu_tx_hold_bonus(tx, szp->z_id);
3377 	dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name);
3378 	error = dmu_tx_assign(tx, zfsvfs->z_assign);
3379 	if (error) {
3380 		zfs_dirent_unlock(dl);
3381 		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
3382 			dmu_tx_wait(tx);
3383 			dmu_tx_abort(tx);
3384 			goto top;
3385 		}
3386 		dmu_tx_abort(tx);
3387 		ZFS_EXIT(zfsvfs);
3388 		return (error);
3389 	}
3390 
3391 	error = zfs_link_create(dl, szp, tx, 0);
3392 
3393 	if (error == 0) {
3394 		uint64_t txtype = TX_LINK;
3395 		if (flags & FIGNORECASE)
3396 			txtype |= TX_CI;
3397 		zfs_log_link(zilog, tx, txtype, dzp, szp, name);
3398 	}
3399 
3400 	dmu_tx_commit(tx);
3401 
3402 	zfs_dirent_unlock(dl);
3403 
3404 	if (error == 0) {
3405 		vnevent_link(svp, ct);
3406 	}
3407 
3408 	ZFS_EXIT(zfsvfs);
3409 	return (error);
3410 }
3411 
3412 /*
3413  * zfs_null_putapage() is used when the file system has been force
3414  * unmounted. It just drops the pages.
3415  */
3416 /* ARGSUSED */
3417 static int
3418 zfs_null_putapage(vnode_t *vp, page_t *pp, u_offset_t *offp,
3419 		size_t *lenp, int flags, cred_t *cr)
3420 {
3421 	pvn_write_done(pp, B_INVAL|B_FORCE|B_ERROR);
3422 	return (0);
3423 }
3424 
3425 /*
3426  * Push a page out to disk, klustering if possible.
3427  *
3428  *	IN:	vp	- file to push page to.
3429  *		pp	- page to push.
3430  *		flags	- additional flags.
3431  *		cr	- credentials of caller.
3432  *
3433  *	OUT:	offp	- start of range pushed.
3434  *		lenp	- len of range pushed.
3435  *
3436  *	RETURN:	0 if success
3437  *		error code if failure
3438  *
3439  * NOTE: callers must have locked the page to be pushed.  On
3440  * exit, the page (and all other pages in the kluster) must be
3441  * unlocked.
3442  */
3443 /* ARGSUSED */
3444 static int
3445 zfs_putapage(vnode_t *vp, page_t *pp, u_offset_t *offp,
3446 		size_t *lenp, int flags, cred_t *cr)
3447 {
3448 	znode_t		*zp = VTOZ(vp);
3449 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
3450 	zilog_t		*zilog = zfsvfs->z_log;
3451 	dmu_tx_t	*tx;
3452 	rl_t		*rl;
3453 	u_offset_t	off, koff;
3454 	size_t		len, klen;
3455 	uint64_t	filesz;
3456 	int		err;
3457 
3458 	filesz = zp->z_phys->zp_size;
3459 	off = pp->p_offset;
3460 	len = PAGESIZE;
3461 	/*
3462 	 * If our blocksize is bigger than the page size, try to kluster
3463 	 * muiltiple pages so that we write a full block (thus avoiding
3464 	 * a read-modify-write).
3465 	 */
3466 	if (off < filesz && zp->z_blksz > PAGESIZE) {
3467 		if (!ISP2(zp->z_blksz)) {
3468 			/* Only one block in the file. */
3469 			klen = P2ROUNDUP((ulong_t)zp->z_blksz, PAGESIZE);
3470 			koff = 0;
3471 		} else {
3472 			klen = zp->z_blksz;
3473 			koff = P2ALIGN(off, (u_offset_t)klen);
3474 		}
3475 		ASSERT(koff <= filesz);
3476 		if (koff + klen > filesz)
3477 			klen = P2ROUNDUP(filesz - koff, (uint64_t)PAGESIZE);
3478 		pp = pvn_write_kluster(vp, pp, &off, &len, koff, klen, flags);
3479 	}
3480 	ASSERT3U(btop(len), ==, btopr(len));
3481 top:
3482 	rl = zfs_range_lock(zp, off, len, RL_WRITER);
3483 	/*
3484 	 * Can't push pages past end-of-file.
3485 	 */
3486 	filesz = zp->z_phys->zp_size;
3487 	if (off >= filesz) {
3488 		/* ignore all pages */
3489 		err = 0;
3490 		goto out;
3491 	} else if (off + len > filesz) {
3492 		int npages = btopr(filesz - off);
3493 		page_t *trunc;
3494 
3495 		page_list_break(&pp, &trunc, npages);
3496 		/* ignore pages past end of file */
3497 		if (trunc)
3498 			pvn_write_done(trunc, flags);
3499 		len = filesz - off;
3500 	}
3501 
3502 	tx = dmu_tx_create(zfsvfs->z_os);
3503 	dmu_tx_hold_write(tx, zp->z_id, off, len);
3504 	dmu_tx_hold_bonus(tx, zp->z_id);
3505 	err = dmu_tx_assign(tx, zfsvfs->z_assign);
3506 	if (err != 0) {
3507 		if (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
3508 			zfs_range_unlock(rl);
3509 			dmu_tx_wait(tx);
3510 			dmu_tx_abort(tx);
3511 			err = 0;
3512 			goto top;
3513 		}
3514 		dmu_tx_abort(tx);
3515 		goto out;
3516 	}
3517 
3518 	if (zp->z_blksz <= PAGESIZE) {
3519 		caddr_t va = ppmapin(pp, PROT_READ, (caddr_t)-1);
3520 		ASSERT3U(len, <=, PAGESIZE);
3521 		dmu_write(zfsvfs->z_os, zp->z_id, off, len, va, tx);
3522 		ppmapout(va);
3523 	} else {
3524 		err = dmu_write_pages(zfsvfs->z_os, zp->z_id, off, len, pp, tx);
3525 	}
3526 
3527 	if (err == 0) {
3528 		zfs_time_stamper(zp, CONTENT_MODIFIED, tx);
3529 		zfs_log_write(zilog, tx, TX_WRITE, zp, off, len, 0);
3530 		dmu_tx_commit(tx);
3531 	}
3532 
3533 out:
3534 	zfs_range_unlock(rl);
3535 	pvn_write_done(pp, (err ? B_ERROR : 0) | flags);
3536 	if (offp)
3537 		*offp = off;
3538 	if (lenp)
3539 		*lenp = len;
3540 
3541 	return (err);
3542 }
3543 
3544 /*
3545  * Copy the portion of the file indicated from pages into the file.
3546  * The pages are stored in a page list attached to the files vnode.
3547  *
3548  *	IN:	vp	- vnode of file to push page data to.
3549  *		off	- position in file to put data.
3550  *		len	- amount of data to write.
3551  *		flags	- flags to control the operation.
3552  *		cr	- credentials of caller.
3553  *		ct	- caller context.
3554  *
3555  *	RETURN:	0 if success
3556  *		error code if failure
3557  *
3558  * Timestamps:
3559  *	vp - ctime|mtime updated
3560  */
3561 /*ARGSUSED*/
3562 static int
3563 zfs_putpage(vnode_t *vp, offset_t off, size_t len, int flags, cred_t *cr,
3564     caller_context_t *ct)
3565 {
3566 	znode_t		*zp = VTOZ(vp);
3567 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
3568 	page_t		*pp;
3569 	size_t		io_len;
3570 	u_offset_t	io_off;
3571 	uint64_t	filesz;
3572 	int		error = 0;
3573 
3574 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
3575 
3576 	ASSERT(zp->z_dbuf_held && zp->z_phys);
3577 
3578 	if (len == 0) {
3579 		/*
3580 		 * Search the entire vp list for pages >= off.
3581 		 */
3582 		error = pvn_vplist_dirty(vp, (u_offset_t)off, zfs_putapage,
3583 		    flags, cr);
3584 		goto out;
3585 	}
3586 
3587 	filesz = zp->z_phys->zp_size; /* get consistent copy of zp_size */
3588 	if (off > filesz) {
3589 		/* past end of file */
3590 		ZFS_EXIT(zfsvfs);
3591 		return (0);
3592 	}
3593 
3594 	len = MIN(len, filesz - off);
3595 
3596 	for (io_off = off; io_off < off + len; io_off += io_len) {
3597 		if ((flags & B_INVAL) || ((flags & B_ASYNC) == 0)) {
3598 			pp = page_lookup(vp, io_off,
3599 			    (flags & (B_INVAL | B_FREE)) ? SE_EXCL : SE_SHARED);
3600 		} else {
3601 			pp = page_lookup_nowait(vp, io_off,
3602 			    (flags & B_FREE) ? SE_EXCL : SE_SHARED);
3603 		}
3604 
3605 		if (pp != NULL && pvn_getdirty(pp, flags)) {
3606 			int err;
3607 
3608 			/*
3609 			 * Found a dirty page to push
3610 			 */
3611 			err = zfs_putapage(vp, pp, &io_off, &io_len, flags, cr);
3612 			if (err)
3613 				error = err;
3614 		} else {
3615 			io_len = PAGESIZE;
3616 		}
3617 	}
3618 out:
3619 	if ((flags & B_ASYNC) == 0)
3620 		zil_commit(zfsvfs->z_log, UINT64_MAX, zp->z_id);
3621 	ZFS_EXIT(zfsvfs);
3622 	return (error);
3623 }
3624 
3625 /*ARGSUSED*/
3626 void
3627 zfs_inactive(vnode_t *vp, cred_t *cr, caller_context_t *ct)
3628 {
3629 	znode_t	*zp = VTOZ(vp);
3630 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
3631 	int error;
3632 
3633 	rw_enter(&zfsvfs->z_teardown_inactive_lock, RW_READER);
3634 	if (zp->z_dbuf_held == 0) {
3635 		if (vn_has_cached_data(vp)) {
3636 			(void) pvn_vplist_dirty(vp, 0, zfs_null_putapage,
3637 			    B_INVAL, cr);
3638 		}
3639 
3640 		mutex_enter(&zp->z_lock);
3641 		vp->v_count = 0; /* count arrives as 1 */
3642 		if (zp->z_dbuf == NULL) {
3643 			mutex_exit(&zp->z_lock);
3644 			zfs_znode_free(zp);
3645 		} else {
3646 			mutex_exit(&zp->z_lock);
3647 		}
3648 		rw_exit(&zfsvfs->z_teardown_inactive_lock);
3649 		VFS_RELE(zfsvfs->z_vfs);
3650 		return;
3651 	}
3652 
3653 	/*
3654 	 * Attempt to push any data in the page cache.  If this fails
3655 	 * we will get kicked out later in zfs_zinactive().
3656 	 */
3657 	if (vn_has_cached_data(vp)) {
3658 		(void) pvn_vplist_dirty(vp, 0, zfs_putapage, B_INVAL|B_ASYNC,
3659 		    cr);
3660 	}
3661 
3662 	if (zp->z_atime_dirty && zp->z_unlinked == 0) {
3663 		dmu_tx_t *tx = dmu_tx_create(zfsvfs->z_os);
3664 
3665 		dmu_tx_hold_bonus(tx, zp->z_id);
3666 		error = dmu_tx_assign(tx, TXG_WAIT);
3667 		if (error) {
3668 			dmu_tx_abort(tx);
3669 		} else {
3670 			dmu_buf_will_dirty(zp->z_dbuf, tx);
3671 			mutex_enter(&zp->z_lock);
3672 			zp->z_atime_dirty = 0;
3673 			mutex_exit(&zp->z_lock);
3674 			dmu_tx_commit(tx);
3675 		}
3676 	}
3677 
3678 	zfs_zinactive(zp);
3679 	rw_exit(&zfsvfs->z_teardown_inactive_lock);
3680 }
3681 
3682 /*
3683  * Bounds-check the seek operation.
3684  *
3685  *	IN:	vp	- vnode seeking within
3686  *		ooff	- old file offset
3687  *		noffp	- pointer to new file offset
3688  *		ct	- caller context
3689  *
3690  *	RETURN:	0 if success
3691  *		EINVAL if new offset invalid
3692  */
3693 /* ARGSUSED */
3694 static int
3695 zfs_seek(vnode_t *vp, offset_t ooff, offset_t *noffp,
3696     caller_context_t *ct)
3697 {
3698 	if (vp->v_type == VDIR)
3699 		return (0);
3700 	return ((*noffp < 0 || *noffp > MAXOFFSET_T) ? EINVAL : 0);
3701 }
3702 
3703 /*
3704  * Pre-filter the generic locking function to trap attempts to place
3705  * a mandatory lock on a memory mapped file.
3706  */
3707 static int
3708 zfs_frlock(vnode_t *vp, int cmd, flock64_t *bfp, int flag, offset_t offset,
3709     flk_callback_t *flk_cbp, cred_t *cr, caller_context_t *ct)
3710 {
3711 	znode_t *zp = VTOZ(vp);
3712 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
3713 	int error;
3714 
3715 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
3716 
3717 	/*
3718 	 * We are following the UFS semantics with respect to mapcnt
3719 	 * here: If we see that the file is mapped already, then we will
3720 	 * return an error, but we don't worry about races between this
3721 	 * function and zfs_map().
3722 	 */
3723 	if (zp->z_mapcnt > 0 && MANDMODE((mode_t)zp->z_phys->zp_mode)) {
3724 		ZFS_EXIT(zfsvfs);
3725 		return (EAGAIN);
3726 	}
3727 	error = fs_frlock(vp, cmd, bfp, flag, offset, flk_cbp, cr, ct);
3728 	ZFS_EXIT(zfsvfs);
3729 	return (error);
3730 }
3731 
3732 /*
3733  * If we can't find a page in the cache, we will create a new page
3734  * and fill it with file data.  For efficiency, we may try to fill
3735  * multiple pages at once (klustering).
3736  */
3737 static int
3738 zfs_fillpage(vnode_t *vp, u_offset_t off, struct seg *seg,
3739     caddr_t addr, page_t *pl[], size_t plsz, enum seg_rw rw)
3740 {
3741 	znode_t *zp = VTOZ(vp);
3742 	page_t *pp, *cur_pp;
3743 	objset_t *os = zp->z_zfsvfs->z_os;
3744 	caddr_t va;
3745 	u_offset_t io_off, total;
3746 	uint64_t oid = zp->z_id;
3747 	size_t io_len;
3748 	uint64_t filesz;
3749 	int err;
3750 
3751 	/*
3752 	 * If we are only asking for a single page don't bother klustering.
3753 	 */
3754 	filesz = zp->z_phys->zp_size; /* get consistent copy of zp_size */
3755 	if (off >= filesz)
3756 		return (EFAULT);
3757 	if (plsz == PAGESIZE || zp->z_blksz <= PAGESIZE) {
3758 		io_off = off;
3759 		io_len = PAGESIZE;
3760 		pp = page_create_va(vp, io_off, io_len, PG_WAIT, seg, addr);
3761 	} else {
3762 		/*
3763 		 * Try to fill a kluster of pages (a blocks worth).
3764 		 */
3765 		size_t klen;
3766 		u_offset_t koff;
3767 
3768 		if (!ISP2(zp->z_blksz)) {
3769 			/* Only one block in the file. */
3770 			klen = P2ROUNDUP((ulong_t)zp->z_blksz, PAGESIZE);
3771 			koff = 0;
3772 		} else {
3773 			/*
3774 			 * It would be ideal to align our offset to the
3775 			 * blocksize but doing so has resulted in some
3776 			 * strange application crashes. For now, we
3777 			 * leave the offset as is and only adjust the
3778 			 * length if we are off the end of the file.
3779 			 */
3780 			koff = off;
3781 			klen = plsz;
3782 		}
3783 		ASSERT(koff <= filesz);
3784 		if (koff + klen > filesz)
3785 			klen = P2ROUNDUP(filesz, (uint64_t)PAGESIZE) - koff;
3786 		ASSERT3U(off, >=, koff);
3787 		ASSERT3U(off, <, koff + klen);
3788 		pp = pvn_read_kluster(vp, off, seg, addr, &io_off,
3789 		    &io_len, koff, klen, 0);
3790 	}
3791 	if (pp == NULL) {
3792 		/*
3793 		 * Some other thread entered the page before us.
3794 		 * Return to zfs_getpage to retry the lookup.
3795 		 */
3796 		*pl = NULL;
3797 		return (0);
3798 	}
3799 
3800 	/*
3801 	 * Fill the pages in the kluster.
3802 	 */
3803 	cur_pp = pp;
3804 	for (total = io_off + io_len; io_off < total; io_off += PAGESIZE) {
3805 		ASSERT3U(io_off, ==, cur_pp->p_offset);
3806 		va = ppmapin(cur_pp, PROT_READ | PROT_WRITE, (caddr_t)-1);
3807 		err = dmu_read(os, oid, io_off, PAGESIZE, va);
3808 		ppmapout(va);
3809 		if (err) {
3810 			/* On error, toss the entire kluster */
3811 			pvn_read_done(pp, B_ERROR);
3812 			return (err);
3813 		}
3814 		cur_pp = cur_pp->p_next;
3815 	}
3816 out:
3817 	/*
3818 	 * Fill in the page list array from the kluster.  If
3819 	 * there are too many pages in the kluster, return
3820 	 * as many pages as possible starting from the desired
3821 	 * offset `off'.
3822 	 * NOTE: the page list will always be null terminated.
3823 	 */
3824 	pvn_plist_init(pp, pl, plsz, off, io_len, rw);
3825 
3826 	return (0);
3827 }
3828 
3829 /*
3830  * Return pointers to the pages for the file region [off, off + len]
3831  * in the pl array.  If plsz is greater than len, this function may
3832  * also return page pointers from before or after the specified
3833  * region (i.e. some region [off', off' + plsz]).  These additional
3834  * pages are only returned if they are already in the cache, or were
3835  * created as part of a klustered read.
3836  *
3837  *	IN:	vp	- vnode of file to get data from.
3838  *		off	- position in file to get data from.
3839  *		len	- amount of data to retrieve.
3840  *		plsz	- length of provided page list.
3841  *		seg	- segment to obtain pages for.
3842  *		addr	- virtual address of fault.
3843  *		rw	- mode of created pages.
3844  *		cr	- credentials of caller.
3845  *		ct	- caller context.
3846  *
3847  *	OUT:	protp	- protection mode of created pages.
3848  *		pl	- list of pages created.
3849  *
3850  *	RETURN:	0 if success
3851  *		error code if failure
3852  *
3853  * Timestamps:
3854  *	vp - atime updated
3855  */
3856 /* ARGSUSED */
3857 static int
3858 zfs_getpage(vnode_t *vp, offset_t off, size_t len, uint_t *protp,
3859 	page_t *pl[], size_t plsz, struct seg *seg, caddr_t addr,
3860 	enum seg_rw rw, cred_t *cr, caller_context_t *ct)
3861 {
3862 	znode_t		*zp = VTOZ(vp);
3863 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
3864 	page_t		*pp, **pl0 = pl;
3865 	int		need_unlock = 0, err = 0;
3866 	offset_t	orig_off;
3867 
3868 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
3869 
3870 	if (protp)
3871 		*protp = PROT_ALL;
3872 
3873 	ASSERT(zp->z_dbuf_held && zp->z_phys);
3874 
3875 	/* no faultahead (for now) */
3876 	if (pl == NULL) {
3877 		ZFS_EXIT(zfsvfs);
3878 		return (0);
3879 	}
3880 
3881 	/* can't fault past EOF */
3882 	if (off >= zp->z_phys->zp_size) {
3883 		ZFS_EXIT(zfsvfs);
3884 		return (EFAULT);
3885 	}
3886 	orig_off = off;
3887 
3888 	/*
3889 	 * If we already own the lock, then we must be page faulting
3890 	 * in the middle of a write to this file (i.e., we are writing
3891 	 * to this file using data from a mapped region of the file).
3892 	 */
3893 	if (rw_owner(&zp->z_map_lock) != curthread) {
3894 		rw_enter(&zp->z_map_lock, RW_WRITER);
3895 		need_unlock = TRUE;
3896 	}
3897 
3898 	/*
3899 	 * Loop through the requested range [off, off + len] looking
3900 	 * for pages.  If we don't find a page, we will need to create
3901 	 * a new page and fill it with data from the file.
3902 	 */
3903 	while (len > 0) {
3904 		if (plsz < PAGESIZE)
3905 			break;
3906 		if (pp = page_lookup(vp, off, SE_SHARED)) {
3907 			*pl++ = pp;
3908 			off += PAGESIZE;
3909 			addr += PAGESIZE;
3910 			len -= PAGESIZE;
3911 			plsz -= PAGESIZE;
3912 		} else {
3913 			err = zfs_fillpage(vp, off, seg, addr, pl, plsz, rw);
3914 			if (err)
3915 				goto out;
3916 			/*
3917 			 * klustering may have changed our region
3918 			 * to be block aligned.
3919 			 */
3920 			if (((pp = *pl) != 0) && (off != pp->p_offset)) {
3921 				int delta = off - pp->p_offset;
3922 				len += delta;
3923 				off -= delta;
3924 				addr -= delta;
3925 			}
3926 			while (*pl) {
3927 				pl++;
3928 				off += PAGESIZE;
3929 				addr += PAGESIZE;
3930 				plsz -= PAGESIZE;
3931 				if (len > PAGESIZE)
3932 					len -= PAGESIZE;
3933 				else
3934 					len = 0;
3935 			}
3936 		}
3937 	}
3938 
3939 	/*
3940 	 * Fill out the page array with any pages already in the cache.
3941 	 */
3942 	while (plsz > 0) {
3943 		pp = page_lookup_nowait(vp, off, SE_SHARED);
3944 		if (pp == NULL)
3945 			break;
3946 		*pl++ = pp;
3947 		off += PAGESIZE;
3948 		plsz -= PAGESIZE;
3949 	}
3950 
3951 	ZFS_ACCESSTIME_STAMP(zfsvfs, zp);
3952 out:
3953 	/*
3954 	 * We can't grab the range lock for the page as reader which would
3955 	 * stop truncation as this leads to deadlock. So we need to recheck
3956 	 * the file size.
3957 	 */
3958 	if (orig_off >= zp->z_phys->zp_size)
3959 		err = EFAULT;
3960 	if (err) {
3961 		/*
3962 		 * Release any pages we have previously locked.
3963 		 */
3964 		while (pl > pl0)
3965 			page_unlock(*--pl);
3966 	}
3967 
3968 	*pl = NULL;
3969 
3970 	if (need_unlock)
3971 		rw_exit(&zp->z_map_lock);
3972 
3973 	ZFS_EXIT(zfsvfs);
3974 	return (err);
3975 }
3976 
3977 /*
3978  * Request a memory map for a section of a file.  This code interacts
3979  * with common code and the VM system as follows:
3980  *
3981  *	common code calls mmap(), which ends up in smmap_common()
3982  *
3983  *	this calls VOP_MAP(), which takes you into (say) zfs
3984  *
3985  *	zfs_map() calls as_map(), passing segvn_create() as the callback
3986  *
3987  *	segvn_create() creates the new segment and calls VOP_ADDMAP()
3988  *
3989  *	zfs_addmap() updates z_mapcnt
3990  */
3991 /*ARGSUSED*/
3992 static int
3993 zfs_map(vnode_t *vp, offset_t off, struct as *as, caddr_t *addrp,
3994     size_t len, uchar_t prot, uchar_t maxprot, uint_t flags, cred_t *cr,
3995     caller_context_t *ct)
3996 {
3997 	znode_t *zp = VTOZ(vp);
3998 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
3999 	segvn_crargs_t	vn_a;
4000 	int		error;
4001 
4002 	if ((prot & PROT_WRITE) &&
4003 	    (zp->z_phys->zp_flags & (ZFS_IMMUTABLE | ZFS_READONLY |
4004 	    ZFS_APPENDONLY)))
4005 		return (EPERM);
4006 
4007 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
4008 
4009 	if (vp->v_flag & VNOMAP) {
4010 		ZFS_EXIT(zfsvfs);
4011 		return (ENOSYS);
4012 	}
4013 
4014 	if (off < 0 || len > MAXOFFSET_T - off) {
4015 		ZFS_EXIT(zfsvfs);
4016 		return (ENXIO);
4017 	}
4018 
4019 	if (vp->v_type != VREG) {
4020 		ZFS_EXIT(zfsvfs);
4021 		return (ENODEV);
4022 	}
4023 
4024 	/*
4025 	 * If file is locked, disallow mapping.
4026 	 */
4027 	if (MANDMODE((mode_t)zp->z_phys->zp_mode) && vn_has_flocks(vp)) {
4028 		ZFS_EXIT(zfsvfs);
4029 		return (EAGAIN);
4030 	}
4031 
4032 	as_rangelock(as);
4033 	if ((flags & MAP_FIXED) == 0) {
4034 		map_addr(addrp, len, off, 1, flags);
4035 		if (*addrp == NULL) {
4036 			as_rangeunlock(as);
4037 			ZFS_EXIT(zfsvfs);
4038 			return (ENOMEM);
4039 		}
4040 	} else {
4041 		/*
4042 		 * User specified address - blow away any previous mappings
4043 		 */
4044 		(void) as_unmap(as, *addrp, len);
4045 	}
4046 
4047 	vn_a.vp = vp;
4048 	vn_a.offset = (u_offset_t)off;
4049 	vn_a.type = flags & MAP_TYPE;
4050 	vn_a.prot = prot;
4051 	vn_a.maxprot = maxprot;
4052 	vn_a.cred = cr;
4053 	vn_a.amp = NULL;
4054 	vn_a.flags = flags & ~MAP_TYPE;
4055 	vn_a.szc = 0;
4056 	vn_a.lgrp_mem_policy_flags = 0;
4057 
4058 	error = as_map(as, *addrp, len, segvn_create, &vn_a);
4059 
4060 	as_rangeunlock(as);
4061 	ZFS_EXIT(zfsvfs);
4062 	return (error);
4063 }
4064 
4065 /* ARGSUSED */
4066 static int
4067 zfs_addmap(vnode_t *vp, offset_t off, struct as *as, caddr_t addr,
4068     size_t len, uchar_t prot, uchar_t maxprot, uint_t flags, cred_t *cr,
4069     caller_context_t *ct)
4070 {
4071 	uint64_t pages = btopr(len);
4072 
4073 	atomic_add_64(&VTOZ(vp)->z_mapcnt, pages);
4074 	return (0);
4075 }
4076 
4077 /*
4078  * The reason we push dirty pages as part of zfs_delmap() is so that we get a
4079  * more accurate mtime for the associated file.  Since we don't have a way of
4080  * detecting when the data was actually modified, we have to resort to
4081  * heuristics.  If an explicit msync() is done, then we mark the mtime when the
4082  * last page is pushed.  The problem occurs when the msync() call is omitted,
4083  * which by far the most common case:
4084  *
4085  * 	open()
4086  * 	mmap()
4087  * 	<modify memory>
4088  * 	munmap()
4089  * 	close()
4090  * 	<time lapse>
4091  * 	putpage() via fsflush
4092  *
4093  * If we wait until fsflush to come along, we can have a modification time that
4094  * is some arbitrary point in the future.  In order to prevent this in the
4095  * common case, we flush pages whenever a (MAP_SHARED, PROT_WRITE) mapping is
4096  * torn down.
4097  */
4098 /* ARGSUSED */
4099 static int
4100 zfs_delmap(vnode_t *vp, offset_t off, struct as *as, caddr_t addr,
4101     size_t len, uint_t prot, uint_t maxprot, uint_t flags, cred_t *cr,
4102     caller_context_t *ct)
4103 {
4104 	uint64_t pages = btopr(len);
4105 
4106 	ASSERT3U(VTOZ(vp)->z_mapcnt, >=, pages);
4107 	atomic_add_64(&VTOZ(vp)->z_mapcnt, -pages);
4108 
4109 	if ((flags & MAP_SHARED) && (prot & PROT_WRITE) &&
4110 	    vn_has_cached_data(vp))
4111 		(void) VOP_PUTPAGE(vp, off, len, B_ASYNC, cr, ct);
4112 
4113 	return (0);
4114 }
4115 
4116 /*
4117  * Free or allocate space in a file.  Currently, this function only
4118  * supports the `F_FREESP' command.  However, this command is somewhat
4119  * misnamed, as its functionality includes the ability to allocate as
4120  * well as free space.
4121  *
4122  *	IN:	vp	- vnode of file to free data in.
4123  *		cmd	- action to take (only F_FREESP supported).
4124  *		bfp	- section of file to free/alloc.
4125  *		flag	- current file open mode flags.
4126  *		offset	- current file offset.
4127  *		cr	- credentials of caller [UNUSED].
4128  *		ct	- caller context.
4129  *
4130  *	RETURN:	0 if success
4131  *		error code if failure
4132  *
4133  * Timestamps:
4134  *	vp - ctime|mtime updated
4135  */
4136 /* ARGSUSED */
4137 static int
4138 zfs_space(vnode_t *vp, int cmd, flock64_t *bfp, int flag,
4139     offset_t offset, cred_t *cr, caller_context_t *ct)
4140 {
4141 	znode_t		*zp = VTOZ(vp);
4142 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
4143 	uint64_t	off, len;
4144 	int		error;
4145 
4146 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
4147 
4148 top:
4149 	if (cmd != F_FREESP) {
4150 		ZFS_EXIT(zfsvfs);
4151 		return (EINVAL);
4152 	}
4153 
4154 	if (error = convoff(vp, bfp, 0, offset)) {
4155 		ZFS_EXIT(zfsvfs);
4156 		return (error);
4157 	}
4158 
4159 	if (bfp->l_len < 0) {
4160 		ZFS_EXIT(zfsvfs);
4161 		return (EINVAL);
4162 	}
4163 
4164 	off = bfp->l_start;
4165 	len = bfp->l_len; /* 0 means from off to end of file */
4166 
4167 	do {
4168 		error = zfs_freesp(zp, off, len, flag, TRUE);
4169 		/* NB: we already did dmu_tx_wait() if necessary */
4170 	} while (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT);
4171 
4172 	ZFS_EXIT(zfsvfs);
4173 	return (error);
4174 }
4175 
4176 /*ARGSUSED*/
4177 static int
4178 zfs_fid(vnode_t *vp, fid_t *fidp, caller_context_t *ct)
4179 {
4180 	znode_t		*zp = VTOZ(vp);
4181 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
4182 	uint32_t	gen;
4183 	uint64_t	object = zp->z_id;
4184 	zfid_short_t	*zfid;
4185 	int		size, i;
4186 
4187 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
4188 	gen = (uint32_t)zp->z_gen;
4189 
4190 	size = (zfsvfs->z_parent != zfsvfs) ? LONG_FID_LEN : SHORT_FID_LEN;
4191 	if (fidp->fid_len < size) {
4192 		fidp->fid_len = size;
4193 		ZFS_EXIT(zfsvfs);
4194 		return (ENOSPC);
4195 	}
4196 
4197 	zfid = (zfid_short_t *)fidp;
4198 
4199 	zfid->zf_len = size;
4200 
4201 	for (i = 0; i < sizeof (zfid->zf_object); i++)
4202 		zfid->zf_object[i] = (uint8_t)(object >> (8 * i));
4203 
4204 	/* Must have a non-zero generation number to distinguish from .zfs */
4205 	if (gen == 0)
4206 		gen = 1;
4207 	for (i = 0; i < sizeof (zfid->zf_gen); i++)
4208 		zfid->zf_gen[i] = (uint8_t)(gen >> (8 * i));
4209 
4210 	if (size == LONG_FID_LEN) {
4211 		uint64_t	objsetid = dmu_objset_id(zfsvfs->z_os);
4212 		zfid_long_t	*zlfid;
4213 
4214 		zlfid = (zfid_long_t *)fidp;
4215 
4216 		for (i = 0; i < sizeof (zlfid->zf_setid); i++)
4217 			zlfid->zf_setid[i] = (uint8_t)(objsetid >> (8 * i));
4218 
4219 		/* XXX - this should be the generation number for the objset */
4220 		for (i = 0; i < sizeof (zlfid->zf_setgen); i++)
4221 			zlfid->zf_setgen[i] = 0;
4222 	}
4223 
4224 	ZFS_EXIT(zfsvfs);
4225 	return (0);
4226 }
4227 
4228 static int
4229 zfs_pathconf(vnode_t *vp, int cmd, ulong_t *valp, cred_t *cr,
4230     caller_context_t *ct)
4231 {
4232 	znode_t		*zp, *xzp;
4233 	zfsvfs_t	*zfsvfs;
4234 	zfs_dirlock_t	*dl;
4235 	int		error;
4236 
4237 	switch (cmd) {
4238 	case _PC_LINK_MAX:
4239 		*valp = ULONG_MAX;
4240 		return (0);
4241 
4242 	case _PC_FILESIZEBITS:
4243 		*valp = 64;
4244 		return (0);
4245 
4246 	case _PC_XATTR_EXISTS:
4247 		zp = VTOZ(vp);
4248 		zfsvfs = zp->z_zfsvfs;
4249 		ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
4250 		*valp = 0;
4251 		error = zfs_dirent_lock(&dl, zp, "", &xzp,
4252 		    ZXATTR | ZEXISTS | ZSHARED, NULL, NULL);
4253 		if (error == 0) {
4254 			zfs_dirent_unlock(dl);
4255 			if (!zfs_dirempty(xzp))
4256 				*valp = 1;
4257 			VN_RELE(ZTOV(xzp));
4258 		} else if (error == ENOENT) {
4259 			/*
4260 			 * If there aren't extended attributes, it's the
4261 			 * same as having zero of them.
4262 			 */
4263 			error = 0;
4264 		}
4265 		ZFS_EXIT(zfsvfs);
4266 		return (error);
4267 
4268 	case _PC_SATTR_ENABLED:
4269 	case _PC_SATTR_EXISTS:
4270 		zp = VTOZ(vp);
4271 		*valp = vfs_has_feature(vp->v_vfsp, VFSFT_XVATTR) &&
4272 		    (vp->v_type == VREG || vp->v_type == VDIR);
4273 		return (0);
4274 
4275 	case _PC_ACL_ENABLED:
4276 		*valp = _ACL_ACE_ENABLED;
4277 		return (0);
4278 
4279 	case _PC_MIN_HOLE_SIZE:
4280 		*valp = (ulong_t)SPA_MINBLOCKSIZE;
4281 		return (0);
4282 
4283 	default:
4284 		return (fs_pathconf(vp, cmd, valp, cr, ct));
4285 	}
4286 }
4287 
4288 /*ARGSUSED*/
4289 static int
4290 zfs_getsecattr(vnode_t *vp, vsecattr_t *vsecp, int flag, cred_t *cr,
4291     caller_context_t *ct)
4292 {
4293 	znode_t *zp = VTOZ(vp);
4294 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
4295 	int error;
4296 	boolean_t skipaclchk = (flag & ATTR_NOACLCHECK) ? B_TRUE : B_FALSE;
4297 
4298 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
4299 	error = zfs_getacl(zp, vsecp, skipaclchk, cr);
4300 	ZFS_EXIT(zfsvfs);
4301 
4302 	return (error);
4303 }
4304 
4305 /*ARGSUSED*/
4306 static int
4307 zfs_setsecattr(vnode_t *vp, vsecattr_t *vsecp, int flag, cred_t *cr,
4308     caller_context_t *ct)
4309 {
4310 	znode_t *zp = VTOZ(vp);
4311 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
4312 	int error;
4313 	boolean_t skipaclchk = (flag & ATTR_NOACLCHECK) ? B_TRUE : B_FALSE;
4314 
4315 	ZFS_ENTER_VERIFY_ZP(zfsvfs, zp);
4316 	error = zfs_setacl(zp, vsecp, skipaclchk, cr);
4317 	ZFS_EXIT(zfsvfs);
4318 	return (error);
4319 }
4320 
4321 /*
4322  * Predeclare these here so that the compiler assumes that
4323  * this is an "old style" function declaration that does
4324  * not include arguments => we won't get type mismatch errors
4325  * in the initializations that follow.
4326  */
4327 static int zfs_inval();
4328 static int zfs_isdir();
4329 
4330 static int
4331 zfs_inval()
4332 {
4333 	return (EINVAL);
4334 }
4335 
4336 static int
4337 zfs_isdir()
4338 {
4339 	return (EISDIR);
4340 }
4341 /*
4342  * Directory vnode operations template
4343  */
4344 vnodeops_t *zfs_dvnodeops;
4345 const fs_operation_def_t zfs_dvnodeops_template[] = {
4346 	VOPNAME_OPEN,		{ .vop_open = zfs_open },
4347 	VOPNAME_CLOSE,		{ .vop_close = zfs_close },
4348 	VOPNAME_READ,		{ .error = zfs_isdir },
4349 	VOPNAME_WRITE,		{ .error = zfs_isdir },
4350 	VOPNAME_IOCTL,		{ .vop_ioctl = zfs_ioctl },
4351 	VOPNAME_GETATTR,	{ .vop_getattr = zfs_getattr },
4352 	VOPNAME_SETATTR,	{ .vop_setattr = zfs_setattr },
4353 	VOPNAME_ACCESS,		{ .vop_access = zfs_access },
4354 	VOPNAME_LOOKUP,		{ .vop_lookup = zfs_lookup },
4355 	VOPNAME_CREATE,		{ .vop_create = zfs_create },
4356 	VOPNAME_REMOVE,		{ .vop_remove = zfs_remove },
4357 	VOPNAME_LINK,		{ .vop_link = zfs_link },
4358 	VOPNAME_RENAME,		{ .vop_rename = zfs_rename },
4359 	VOPNAME_MKDIR,		{ .vop_mkdir = zfs_mkdir },
4360 	VOPNAME_RMDIR,		{ .vop_rmdir = zfs_rmdir },
4361 	VOPNAME_READDIR,	{ .vop_readdir = zfs_readdir },
4362 	VOPNAME_SYMLINK,	{ .vop_symlink = zfs_symlink },
4363 	VOPNAME_FSYNC,		{ .vop_fsync = zfs_fsync },
4364 	VOPNAME_INACTIVE,	{ .vop_inactive = zfs_inactive },
4365 	VOPNAME_FID,		{ .vop_fid = zfs_fid },
4366 	VOPNAME_SEEK,		{ .vop_seek = zfs_seek },
4367 	VOPNAME_PATHCONF,	{ .vop_pathconf = zfs_pathconf },
4368 	VOPNAME_GETSECATTR,	{ .vop_getsecattr = zfs_getsecattr },
4369 	VOPNAME_SETSECATTR,	{ .vop_setsecattr = zfs_setsecattr },
4370 	VOPNAME_VNEVENT, 	{ .vop_vnevent = fs_vnevent_support },
4371 	NULL,			NULL
4372 };
4373 
4374 /*
4375  * Regular file vnode operations template
4376  */
4377 vnodeops_t *zfs_fvnodeops;
4378 const fs_operation_def_t zfs_fvnodeops_template[] = {
4379 	VOPNAME_OPEN,		{ .vop_open = zfs_open },
4380 	VOPNAME_CLOSE,		{ .vop_close = zfs_close },
4381 	VOPNAME_READ,		{ .vop_read = zfs_read },
4382 	VOPNAME_WRITE,		{ .vop_write = zfs_write },
4383 	VOPNAME_IOCTL,		{ .vop_ioctl = zfs_ioctl },
4384 	VOPNAME_GETATTR,	{ .vop_getattr = zfs_getattr },
4385 	VOPNAME_SETATTR,	{ .vop_setattr = zfs_setattr },
4386 	VOPNAME_ACCESS,		{ .vop_access = zfs_access },
4387 	VOPNAME_LOOKUP,		{ .vop_lookup = zfs_lookup },
4388 	VOPNAME_RENAME,		{ .vop_rename = zfs_rename },
4389 	VOPNAME_FSYNC,		{ .vop_fsync = zfs_fsync },
4390 	VOPNAME_INACTIVE,	{ .vop_inactive = zfs_inactive },
4391 	VOPNAME_FID,		{ .vop_fid = zfs_fid },
4392 	VOPNAME_SEEK,		{ .vop_seek = zfs_seek },
4393 	VOPNAME_FRLOCK,		{ .vop_frlock = zfs_frlock },
4394 	VOPNAME_SPACE,		{ .vop_space = zfs_space },
4395 	VOPNAME_GETPAGE,	{ .vop_getpage = zfs_getpage },
4396 	VOPNAME_PUTPAGE,	{ .vop_putpage = zfs_putpage },
4397 	VOPNAME_MAP,		{ .vop_map = zfs_map },
4398 	VOPNAME_ADDMAP,		{ .vop_addmap = zfs_addmap },
4399 	VOPNAME_DELMAP,		{ .vop_delmap = zfs_delmap },
4400 	VOPNAME_PATHCONF,	{ .vop_pathconf = zfs_pathconf },
4401 	VOPNAME_GETSECATTR,	{ .vop_getsecattr = zfs_getsecattr },
4402 	VOPNAME_SETSECATTR,	{ .vop_setsecattr = zfs_setsecattr },
4403 	VOPNAME_VNEVENT,	{ .vop_vnevent = fs_vnevent_support },
4404 	NULL,			NULL
4405 };
4406 
4407 /*
4408  * Symbolic link vnode operations template
4409  */
4410 vnodeops_t *zfs_symvnodeops;
4411 const fs_operation_def_t zfs_symvnodeops_template[] = {
4412 	VOPNAME_GETATTR,	{ .vop_getattr = zfs_getattr },
4413 	VOPNAME_SETATTR,	{ .vop_setattr = zfs_setattr },
4414 	VOPNAME_ACCESS,		{ .vop_access = zfs_access },
4415 	VOPNAME_RENAME,		{ .vop_rename = zfs_rename },
4416 	VOPNAME_READLINK,	{ .vop_readlink = zfs_readlink },
4417 	VOPNAME_INACTIVE,	{ .vop_inactive = zfs_inactive },
4418 	VOPNAME_FID,		{ .vop_fid = zfs_fid },
4419 	VOPNAME_PATHCONF,	{ .vop_pathconf = zfs_pathconf },
4420 	VOPNAME_VNEVENT,	{ .vop_vnevent = fs_vnevent_support },
4421 	NULL,			NULL
4422 };
4423 
4424 /*
4425  * Extended attribute directory vnode operations template
4426  *	This template is identical to the directory vnodes
4427  *	operation template except for restricted operations:
4428  *		VOP_MKDIR()
4429  *		VOP_SYMLINK()
4430  * Note that there are other restrictions embedded in:
4431  *	zfs_create()	- restrict type to VREG
4432  *	zfs_link()	- no links into/out of attribute space
4433  *	zfs_rename()	- no moves into/out of attribute space
4434  */
4435 vnodeops_t *zfs_xdvnodeops;
4436 const fs_operation_def_t zfs_xdvnodeops_template[] = {
4437 	VOPNAME_OPEN,		{ .vop_open = zfs_open },
4438 	VOPNAME_CLOSE,		{ .vop_close = zfs_close },
4439 	VOPNAME_IOCTL,		{ .vop_ioctl = zfs_ioctl },
4440 	VOPNAME_GETATTR,	{ .vop_getattr = zfs_getattr },
4441 	VOPNAME_SETATTR,	{ .vop_setattr = zfs_setattr },
4442 	VOPNAME_ACCESS,		{ .vop_access = zfs_access },
4443 	VOPNAME_LOOKUP,		{ .vop_lookup = zfs_lookup },
4444 	VOPNAME_CREATE,		{ .vop_create = zfs_create },
4445 	VOPNAME_REMOVE,		{ .vop_remove = zfs_remove },
4446 	VOPNAME_LINK,		{ .vop_link = zfs_link },
4447 	VOPNAME_RENAME,		{ .vop_rename = zfs_rename },
4448 	VOPNAME_MKDIR,		{ .error = zfs_inval },
4449 	VOPNAME_RMDIR,		{ .vop_rmdir = zfs_rmdir },
4450 	VOPNAME_READDIR,	{ .vop_readdir = zfs_readdir },
4451 	VOPNAME_SYMLINK,	{ .error = zfs_inval },
4452 	VOPNAME_FSYNC,		{ .vop_fsync = zfs_fsync },
4453 	VOPNAME_INACTIVE,	{ .vop_inactive = zfs_inactive },
4454 	VOPNAME_FID,		{ .vop_fid = zfs_fid },
4455 	VOPNAME_SEEK,		{ .vop_seek = zfs_seek },
4456 	VOPNAME_PATHCONF,	{ .vop_pathconf = zfs_pathconf },
4457 	VOPNAME_GETSECATTR,	{ .vop_getsecattr = zfs_getsecattr },
4458 	VOPNAME_SETSECATTR,	{ .vop_setsecattr = zfs_setsecattr },
4459 	VOPNAME_VNEVENT,	{ .vop_vnevent = fs_vnevent_support },
4460 	NULL,			NULL
4461 };
4462 
4463 /*
4464  * Error vnode operations template
4465  */
4466 vnodeops_t *zfs_evnodeops;
4467 const fs_operation_def_t zfs_evnodeops_template[] = {
4468 	VOPNAME_INACTIVE,	{ .vop_inactive = zfs_inactive },
4469 	VOPNAME_PATHCONF,	{ .vop_pathconf = zfs_pathconf },
4470 	NULL,			NULL
4471 };
4472